WUSTL Science & Technology News

The need for speed

2012-05-18 00:00:00

David Kilper

Washington University in St. Louis students Matthew Monson (left), a junior in mechanical engineering, and Achal Upadhyaya (center), a senior in mechanical engineering, unveil May 7 WUSTL’s entry in Formula SAE, a student competition to design and drive a Formula-style race car organized by the Society of Automotive Engineers. The WUSTL car runs on E85 (a fuel blend with 85 percent ethanol) and is built of advanced composite materials and features pushbutton shifting. Having just finished finals and the car's construction simultaneously, the team was on its way to the Michigan International Speedway. There, the car competed against 120 teams in skidpad, acceleration, autocross and endurance events. The WUSTL entry performed well until the last event, when the car lost its steering after the first lap of an endurance test. The WUSTL team was started in 2002 and built a car in ’05, ’07 and ’11, as well as this year. This is the second time the team has built a car from start to finish in one year.

Washington People: Sophia Hayes

Tony Fitzpatrick — 2012-05-11 00:00:00

David Kilper

Sophia Hayes, PhD (right), associate professor of chemistry in Arts & Sciences, adjusts a laser in her Loudermann Hall laboratory with chemistry graduate students Dustin Wheeler (left) and Erika Sesti.

It’s the stuff of great novels, movies, TV quiz shows and rational logic. Sophia Hayes, PhD, associate professor of chemistry in Arts & Sciences, faced a tough decision at the dawn of her career.

After finishing an internship at Sandia National Laboratory in 1993, the materials science group there offered her a no-strings-attached grant of about $250,000 to pursue graduate studies at the University of California, Santa Barbara.

There was one sticky stipulation: She had to choose between two professors as her adviser. One was a well-known materials scientist, the other a lesser-known chemist who was doing innovative research in nuclear magnetic resonance (NMR), a field that Hayes found particularly appealing.

Sandia made it clear that, because of a conflict of interest, they could work with one of the professors, but not the other. Thus, everything depended upon “Sophia’s Choice.”

“The Sandia people told me that they didn’t want to influence my choice of research adviser because it would be the most important one I’ll make, second only to whom I would marry,” Hayes says.

Hayes would have gotten a full ride, plus stipend, anyway, but the additional research funds to run an independent project is phenomenal. Hayes felt certain that Sandia was leaning toward the famous materials scientist, but, intellectually, she was drawn to the NMR specialist.

“I agonized for weeks,” she says. “Both professors wanted to know my decision as the deadline approached. At the end, the NMR guy, Hellmut Eckert, told me that he could see it was tearing me up, and he didn’t want me to be so conflicted.

“He said that it would be fine with him if I went with the materials scientist. I thought: ‘Wow, this man is selflessly willing to do this (giving up a huge chunk of funding). That’s it!’

“I got on the phone and told them ‘You probably want the other guy, but it’s got to be Eckert,’ and all this cheering erupted in the background. The conflict would have been with the materials scientist. I was overjoyed.”

Her own spin

That choice heralded Hayes’ extraordinary research saga in NMR, which takes the behavior of nuclear (and electron) spins in magnetic fields and uses them as probes of solid state structure and dynamics and relating these to properties of the system under study.

In medicine, a similar technique is called magnetic resonance imaging (MRI), the test that athletes get to determine injury extent, while NMR is the test that can elucidate enzyme behaviors, polymer and amorphous structures, semiconductor opto-electronics and the behavior and nature of gases and materials for a wide assortment of applications.

At Santa Barbara, Hayes pursued a new wave of NMR research that led to advancements in battery and composite technologies and inspired her to develop her own spin, as it were, on a developing type of NMR, called optically pumped NMR (OPNMR), in which a laser is shined on semiconductor materials held at 6 degrees Kelvin.

Today, she is building Generation III of her technique, which she advanced as a postdoc at Lawrence Livermore National Laboratory and has improved at WUSTL since coming here in 2001.

Semiconductors can conduct electricity under some conditions but not others, making them ideal for controlling electrical current. Silicon is the best-known elemental semiconductor and forms the basis of most integrated circuits in computers. A semiconductor device can perform the function of a vacuum tube — the stuff of old radios and TVs — but the vacuum tube has hundreds of times its volume.

“OPNMR is a great probe of the band structure of a semiconductor, and we are pushing the envelope in detecting the defects at very low concentrations in semiconductors (on the order of 1 in 10,000,000 atoms),” Hayes says.

“If you think of solar energy — solid-state lighting, any kind of photodetection, like a CCD camera — all are based on the process of light hitting a semiconductor that generates electrons or electricity.

“Anything that we can do to improve our understanding of these related phenomena is the aim of our research. We are getting a new laboratory built on the second floor of McMillen Hall with brand new equipment in support of the technique.”

Collaborative science

Another exciting research thrust is a collaborative effort, funded by WUSTL’s Consortium for Clean Coal Utilization, with fellow NMR aficionado Mark Conradi, PhD, professor of physics in Arts & Sciences, and Philip Skemer, PhD, assistant professor of earth and planetary sciences in Arts & Sciences.

Courtesy photo

Sophia Hayes on a sailboat off the coast of California.

In this work, she uses her technique to study the greenhouse gas carbon dioxide and test possible ways of sequestering, or storing, it in safe environments, such as the ocean.

Theoretically, it’s possible to take carbon dioxide, use chemistry to convert it into a solid, such as cement or a mineral, or catalyze it so it changes into something useful, such as methanol.

“A couple of years ago, I went to Mark, a good friend, and told him with all of his expertise in building hardware and high-pressure NMR and gas diffusion, combined with my inorganic chemistry background, we should watch what CO₂ does under pressure and briney conditions such as we’d see in underground CO₂ sequestration sites,” Hayes says.

“We are beginning to see some exciting interactions that open up intriguing possibilities. For instance, NMR allows us to actually see the balance of CO₂ coming into rock and converting to bicarbonate.

“I couldn’t do this on my own,” she says. “It’s because Phil came on board to figure out the important rocks, and, most importantly, Mark to build high-pressure probes that we’ve made the headway that we have.

“This is what I’d always hoped science would be like, highly collaborative, exactly what attracted me as an undergraduate,” Hayes says.

“I really enjoy the collaboration with Professor Hayes,” Conradi says. “Between Sophia, Phil Skemer and me, there are very different areas of expertise.

“The work on the CO₂ project is in the hands of two really talented graduate students from chemistry, Andy Surface and Jeremy Moore. I have enjoyed the collaboration and look forward to extending it.”

Hands-on solving of real-world problems

Hayes, who grew up near Pasadena, Calif., was at the University of California, Berkeley, leaning toward an economics major — her mother’s side of the family had businesses in Japan — when she stumbled into a quantum mechanics class and then a chemistry class with a collaborative research focus.

Courtesy photo

Sophia Hayes’ husband,
Chris Hagedorn, with their daughter, Marina.

Research projects were the hook, and “I crammed the chemistry major into my last two years,” Hayes says.

“I’ve encouraged undergraduate research here because of my positive experiences as an undergrad,” she says. “I loved the hands-on solving of real-world problems, where you might try 50 things and only one works. These projects all involved teams of students working with an adviser. I’m so happy to see cross-collaborations all over our campus now.”

Hayes oversees six graduate students and four undergrads in her lab and is involved locally and on-campus with the university’s Institute for School Partnership, the science outreach program for K-12 schools.

In 2011, she joined researchers at the University of Oregon, Oregon State University and Rutgers University to help direct the National Science Foundation’s new Center for Chemical Innovation, a five-year, $20 million program focused on the search for methods to make the next generation of electronic materials.

“NSF identified us as having great NMR instrumentation, which also is a reflection on Mark (Conradi), Jake Schaefer (PhD, the Charles Allen Thomas Professor of Chemistry), Joe Ackerman (PhD, the William Greenleaf Eliot Professor of Chemistry) and others who have made landmark contributions to NMR,” Hayes says.

“I think this center is working hard for technology transfer out of universities into realizable companies and inventions. It’s terrific to be a part of it.”

Fast facts about Sophia Hayes

Family: Husband, Chris Hagedorn (who graduated from WUSTL in 1995 with a bachelor’s degree in chemical engineering), daughter, Marina, 6. Father, Tom, was an engineer; mother, Tatiana, is an accomplished pianist, half-Japanese, half-Russian. Hayes, thus, is one-quarter Japanese.
Hobbies on vacation: scuba diving, sailing
Education: BS, chemistry, 1990, University of California, Berkeley; PhD, chemistry, 1999, University of California, Santa Barbara
Other choices: Hayes worked as an energy/environmental consultant for three years before pursuing a doctorate. She studied traditional Japanese art for a summer, living in a shrine on the outskirts of Kyoto. She played orchestral clarinet (occasionally bassoon) and contemplated music school in lieu of Berkeley.

Arch Grants awards first $750,000 in grants

2012-05-07 00:00:00

Eleven Washington University in St. Louis-affiliated entrepreneurs are among the winners of $750,000 in inaugural grants from Arch Grants, the global business plan competition providing $50,000 grants to startups and taking no equity in return.

Missouri Gov. Jay Nixon and Jim McKelvey, Square co-founder and head of the Arch Grants Advisory Board, joined Arch Grants today to announce 15 startups that will each receive $50,000 in funding to help launch and grow their business and create a more robust startup culture and infrastructure in St. Louis.

The 11 WUSTL-affiliated winners comprise five alumni, four faculty members and two students.

They are:

Jonathan T.Z. Chen earned a bachelor’s degree in business administration in 2008;
Patrick Crowley, PhD, is an associate professor of computer science & engineering in the School of Engineering & Applied Science;
Peter S. Finley is an adjunct professor of entrepreneurship in the Olin School;
Daniel J. Garcia is a senior in the School of Engineering & Applied Science;
Michael J. Gidding is pursuing a bachelor’s degree in chemical engineering and two master’s degrees, a master of engineering and a master of business administration;
Zhilin Hu, PhD, is a research associate professor of biomedical engineering in the School of Engineering & Applied Science;
Kenneth R. Kline earned a bachelor’s degree in physics in Arts & Sciences and a master’s degree in finance from the Olin School, both in 2008;
Margaret S. Stohr earned an MBA from the Olin School in 1991;
Sergi G. Turabelidze earned a bachelor’s degree in business administration in 2008;
Melissa Walker is an adjunct instructor in the Clinical Research Management program in University College in Arts & Sciences; and
Mark T. Womer earned a bachelor’s degree in chemistry in Arts & Sciences in 1999.

To date, Arch Grants has secured more than $2.9 million in funding from a mix of individual, organizational and corporate donors.

“Small businesses are the biggest driver of job-creation and economic growth in our state,” Nixon said. “As governor, I am committed to helping our startups and small businesses grow, and Arch Grants is another proven tool we are using to do just that. We are extremely proud to have this diverse and innovative group of companies growing, investing and creating jobs right here in Missouri. These pioneering small-business owners will lead our economy and our state into the future.”

“We at Arch Grants are thrilled with the quality and potential of the entrepreneurs who won our international competition out of over 400 applicants,” said Jerry Schlichter, co-founder and president of Arch Grants. “This marks St. Louis as a top destination with a community of high quality startup businesses who will compete in the global economy and Arch Grants will be working hard to build that community as we move forward.”

In its inaugural year, the competition attracted 420 applicants from 12 countries. The 15 winning companies will receive $50,000 in funding as part of a year-long program. Beginning in June, the companies will locate in St. Louis and work toward the goal of attracting additional capital, including up to $100,000 of Arch Grants follow-on funding.

The WUSTL-affiliated entrepreneurs and their winning startups are:

Crowley is CEO and founder and Finley is chief operating officer of Observable Networks, which is pioneering a new approach to enterprise network security and management. Observable Networks is the recipient of the Emerson Arch Grant.

Gidding is president and Garcia is director of science of Saturnis, LLC. Saturnis is commercializing a low-cost, thermochemical process that produces liquid transportation fuels from biomass sources that can be sustainably harvested in the Midwest. Saturnis is the recipient of the Peabody Arch Grant. Himadri B. Pakrasi, PhD, WUSTL’s George William and Irene Koechig Freiberg Professor of Biology in Arts & Sciences and professor of energy in the School of Engineering & Applied Science, is Gidding and Garcia’s faculty adviser.

Hu is CEO of Pharos Scientific, which aims to deliver an innovative medical imaging component in the forefront of diagnostic medicine and related products.

Kline is CEO and co-founder with Chen, who is the chief operating officer, of Med Preps, which provides online practice tests and flashcards to help medical professionals prepare for certification exams.

Turabelidze and Giorgi Gioshvili are co-founders of Iveria TV, the “hulu of foreign TV.” Iveria TV possesses the technological infrastructure and business model to deliver foreign language TV streams to millions of immigrants living in the United States.

Walker is president and chief technology officer and Stohr is chief financial officer of Graematter Inc. Graematter developed the TERI Regulatory Intelligence System, which for the first time consolidates the data and information located in more than 100 regulatory data sources into a single, searchable database. Merle Symes is Graematter’s CEO.

Womer is chief financial officer of Labor Voices, which is crowdsourced supply chain intelligence. Labor Voices provides corporations with a real-time monitoring and risk-management tool, with data coming directly from workers in their supply chains. Kohl Gill is CEO and founder.

“If you are building a business, Arch Grants is the reason to do it in St. Louis,” said McKelvey, a St. Louis native and also a WUSTL alumnus, earning both a bachelor’s degree in economics in Arts & Sciences and a bachelor’s in computer science in 1987. He is also general partner at Cultivation Capital.

“The Arch Grants initiative is an imaginative program that will contribute significantly to the ecosystem for innovation and entrepreneurship in our region and the revitalization of St. Louis,” said Washington University Chancellor Mark S. Wrighton. “I am proud that Washington University-affiliated entrepreneurs are among the first winners and look forward to following the success of all Arch Grants recipients.”

“Entrepreneurs here have worked hard to establish a strong base of innovation in the region,” said Sarah Spear, executive director of Arch Grants. “Arch Grants builds on those early efforts by both retaining entrepreneurs and attracting new entrepreneurs to St. Louis. We’re excited about building this game-changing program here in St. Louis. We look forward to grant recipients joining us downtown in June, increasing the entrepreneurial bench strength and innovation in the region.”

Support has been provided by the founders, Missouri Technology Corporation, the Community Improvement District of the Partnership for Downtown St. Louis, individual donors, and large corporate donors.

For a complete list of Arch Grants winners, visit http://archgrants.org.

About Arch Grants

Arch Grants is creating an entrepreneurial culture and infrastructure to increase employment growth in the St. Louis area. Launching multiple high quality, new ventures simultaneously, Arch Grants will also help build the image of St. Louis among aspiring entrepreneurs and others looking to have a formative role in building a new entrepreneurial climate in St. Louis.

Arch Grants seeks to develop an environment in St. Louis where entrepreneurs and young people want to start and grow businesses and live in a vibrant community that is affordable and where there’s a huge level of support from business and community leaders.

Lecture, symposium honors Sam Weissman’s 100th birthday

2012-05-02 00:00:00

June 25 marks the 100th birthday of Samuel “Sam” Issac Weissman, PhD, beloved professor of chemistry at Washington University in St. Louis who died at 94 in 2007.

To recognize the birth 100 years ago of this Manhattan Project scientist and beloved teacher, who developed the technique of electron spin resonance (ESR) to probe the structure of molecules, WUSTL’s Department of Chemistry in Arts & Sciences is hosting a poster session, lecture and symposium Thursday and Friday, May 10 and 11.

The poster session will kick off the festivities at 2:30 p.m. Thursday, May 10 in Room 461, Louderman Hall.

At 4 p.m. the second annual Weissman Lecture will begin in Room 458 in Louderman Hall. Charles Slichter, PhD, emeritus professor of physics at the University of Illinois, will speak on nuclear magnetic resonance, a powerful analytical technique to whose sibling technique ESR made pioneering contributions.

Slichter will describe the burst of creativity that followed the discovery of nuclear magnetic resonance in 1946 and the many uses to which the new technique was put. Invented to study the properties of the nuclei of atoms, it moved first into condensed matter physics, then into chemistry, biology, and lastly into medicine, where it became the basis for Magnetic Resonance Imaging.

The talk is free and open to the public, as is the symposium the following day.

The following day, a scientific symposium will be held in Room 458 Louderman Hall, beginning at 9 a.m. The symposium will be a homecoming for Weissman’s former students, postdocs and friends.

In addition to Slichter and Weissman’s son Michael B. Weissman, PhD, professor emeritus of physics at the University of Illinois at Urbana-Champaign, symposium participants will include faculty from Massachusetts Institute of Technology, Tohoku University in Japan, the Freiberg University in Germany, Stanford University, Missouri University of Science and Technology, Southern Illinois University, Carbondale and Loyola University Chicago.

About Sam Weissman

Weissman’s career is inextricably entwined with the history of the chemistry department and of WUSTL.

Herb Weitman

Sam Weissman, then an assistant professor of chemistry, and Jonathan Townsen, then an assistant professor of physics, examine magnetic resonance data in Crow Hall about 1962. Townsend built the early ESR spectrometers that Weissman worked with.

This history is elegantly described in the Rettner Gallery of the Lab Sciences Building, where portraits of the six scientists who founded the modern chemistry department hang.

The captions for the portraits were written by Alfred M. Holtzer, PhD, emeritus professor of chemistry, who was a student of five of the six chemists before becoming their fellow scientist and colleague.

Holtzer wrote:

Just after WW II, the Washington University Chemistry Department comprised only three members, none active in research. The Board of Trustees decided to raise the University’s scholarly level to include research as well as teaching. To that end, they appointed physics Nobel Laureate Arthur Holly Compton, a former WU faculty member, as Chancellor. Compton had been an important figure in the Manhattan Project that created the atomic bombs. In 1946, he recruited to WU from the Los Alamos campus of the Manhattan Project, the six chemists whose portraits are hung in this Rettner Gallery.

They brought with them from Los Alamos, not only outstanding scientific gifts,” Holtzer continued, “but also a spirit and an attitude, featuring irreverence toward entrenched authority, fierce devotion to academic freedom, uncompromising intellectual honesty, and a love of science that soon pervaded the atmosphere. Together, the six created the modern, teacher-scientist Chemistry Department that still flourishes at WUSTL today.

Educated in Chicago’s public schools, Weissman earned his bachelor’s and doctoral degrees in physical chemistry at the University of Chicago. He then moved to the University of California-Berkeley to work in the laboratory of Gilbert Newton Lewis (familiar to chemistry students everywhere as the author of the Lewis dot diagram shorthand used to figure out the bonds between atoms in molecules).

In Lewis’ lab, Weissman studied the optical properties of the rare earth metals, laying the foundation for certain lasers.

During 1942-43, he worked on isotope separation techniques needed to prepare fissionable material for a uranium bomb at Berkeley’s Radiation Laboratory, moving to Los Alamos in 1943 where he was a group leader in the Manhattan Project and worked on the design of a plutonium bomb.

In an article about the Manhattan Project that ran in the Washington University Magazine, the five surviving chemists discuss their ambivalence about the bomb.

They were under the impression the German bomb program was quite advanced and were shocked when they later learned how little progress the Germans had actually made. They were also aware that fighting island to island in the South Pacific was taking a horrific toll in lives.

But they still had misgivings, perhaps Weisman more than the others. “I think we would all have been relieved it had been demonstrated that it couldn’t possibly work,” he said of the bomb.

He was the only one of the six who didn’t witness the first atomic bomb test at Trinity. He stayed at home with what he called “a psychogenic bellyache.”

After he moved to WUSTL, Weisman focused on ESR, a technique related to nuclear magnetic resonance (NMR) in which transitions between electronic rather than nuclear spin levels are detected.

Although nuclear magnetic resonance is familiar to most of us as a medical imaging technique, NMR and ESR can also be used to obtain information about the structure of molecules and to measure the rates of very fast reactions, and it was these spectroscopic applications Weissman explored.

He was elected a Fellow of the American Academy of Arts and Sciences a member of the National Academy of Sciences, both in 1966.

Weissman remained a regular presence in the department even after his retirement in 1980, discussing research and planning experiments with colleagues and students up until just before he died.

For more information about the lecture and symposium, contact Tom Lin at Lin@wustl.edu.

Math students score in Putnam, win and show in Missouri math competition

2012-04-24 00:00:00

Hang Chen

WUSTL contestants debrief after the Missouri Collegiate Mathematics Competition with their sponsor Ron Freiwald, PhD, professor of mathematics. They are (clockwise from lower left) Josh Levin, Tom Morrell, Alan Talmage, Matt Halpern, Freiwald, Ari Tenzer and Jason Zhang.

The Department of Mathematics in Arts & Sciences at Washington University in St. Louis has announced the results of the 72nd William Lowell Putnam Mathematics Competition.

The university fielded 16 students in the competition, which was held on the first Saturday in December 2011. Altogether, 572 colleges and universities in the United States and Canada took part.

Three students must be designated in advance as the school team, and the team score is based on the three individual scores.

This year, the WUSTL team, consisting of senior Alex Anderson and juniors Tom Morrell and Ari Tenzer, placed 28th out of 460 teams.

"My toughest task is picking the students for the team,” says Victor Wickerhauser, PhD, professor of mathematics and this year’s Putnam coach. "It’s not really possible to predict how students will perform,” he says, “but we convince ourselves each year that we can.

Individual performances also are ranked. Anderson earned an honorable mention with a rank of 26 out of 4,440 contestants. Two other students ranked in the top 200 and one more in the top 250.

Hang Chen

Anderson

Anderson will be awarded the Putnam Exam Prize this year. The prize is given to a graduating senior who has done exceptionally well on the Putnam exam during his or her time at WUSTL.

The exam consists of two three-hour sessions during which contestants work individually on 12 problems.

“It’s a very hard test,” says Wickerhauser. “The median score is zero. More than half the people who try it make no progress on any of the 12 problems and get a zero.”

The problems are famous for testing ingenuity and cleverness rather than profound mathematical insight. “Typically,” Wickerhauser says, “they belong to a class of problems that are not solvable, but the one selected for the Putnam has some special properties that make it solvable.

“So those who are good at the Putnam exam are those who are quick to locate the central difficulty of a problem and quick to realize this problem doesn’t have the central difficulty because of some quirk or a particular choice of numbers.”

The exam is based in part on the famous tripos, the competition held at the University of Cambridge in England that also rewards cleverness and thinking on one’s feet, says Wickerhauser. Those who gain ‘first-class’ degrees in this competition are called Wranglers and the highest scorer is the Senior Wrangler.

“The students who take the Putnam really enjoy it,” Wickerhauser says. “For the real Wranglers like Alex, this is a very pleasant activity.”

“My goal was pleasure,” Anderson says. He explains that he was tired of grinding through problem sets in the three physics courses he was taking that term, and was looking forward to “using a limited set of ideas in clever ways rather than learning a breadth of new concepts.”

This doesn’t mean there is never any grousing. Between the morning and the afternoon sessions this year, Wickerhauser took the students to lunch where they pronounced one of the morning’s problems as ‘evil.’

“You were supposed to find all of the numbers for which some property held,” Wickerhauser says, “and there were eight solutions. The first seven you could find by elegant thinking, and to get the eighth you had to work out a whole bunch of cases to convince yourself it was true.”

Elizabeth Lowell Putnam established the William Lowell Putnam Intercollegiate Memorial Fund in memory of her husband, who graduated in mathematics from Harvard. The first competition was held in 1938 and the contest has been sponsored since then by the Mathematical Association of America.

Students prepare for the Putnam during Friday afternoon practice sessions in the fall semester. The practices featured free pizza, paid for by the mathematics department from money won by past Putnam teams. (The top team can win as much as $25,000.)

An archive of Putnam problems can be found at the Putnam Competition Directory.

Missouri Collegiate Mathematics Competition

Hang Chen

A WUSTL team took first place in the competition. The winning team members, here consulting on a problem, were (from left), freshman Alan Talmage, and juniors Tom Morrell and Ari Tenzer.

WUSTL math students also did well in the 17th annual Missouri Collegiate Mathematics Competition, held April 12 and 13 on the campus of the University of Missouri-St. Louis. Forty-one teams from colleges and universities across Missouri took part.

The two WUSTL teams took first and third place. A team consisting of freshman Alan Talmage and juniors Morrell and Tenzer captured first place. The second team consisting of sophomore Jason Zhang and juniors Matt Halpern and Josh Levin took third place.

“It was a little scary going into the competition as the only freshman,” Talmage says, “but after making it through both sessions, I think that I have gained valuable experience — it was grueling, but it was also fun.”

Wickerhauser notes that several freshmen did well on the Putnam, which means the department should be able to field strong teams in the next three years.

The competition consists of two sessions, in each of which teams work collaboratively on five problems for two-and-a-half hours. It is sponsored by the Missouri section of the Mathematical Association of America and began in 1996. Since then, a WUSTL team has captured first place 11 times.

The faculty sponsors for the competition were Russ Woodroofe, PhD, the Chauvenet Postdoctoral Lecturer in Mathematics, and Edward Wilson, PhD, professor emeritus of mathematics.

To view this year’s problems from the state competition, visit the competition’s site.

Spector Prize goes to Fahey

2012-04-24 00:00:00

Each year, the Department of Biology in Arts & Sciences at Washington University in St. Louis awards a prize to a graduating senior in memory of Marion Smith Spector, a 1938 WUSTL graduate who studied zoology under the late Viktor Hamburger, PhD.

Fahey

Hamburger was a professor of biology and a prominent developmental biologist who made many important contributions while a WUSTL faculty member.

The Spector Prize, first awarded in 1974, recognizes academic excellence and outstanding undergraduate achievement in research. Students are nominated by their research mentors for outstanding research that has made substantial contributions to a field.

This year, the prize has been awarded to Paul Fahey, who graduated in December 2011 summa cum laude with a bachelor’s degree in biology.

Fahey worked in the lab of Karen O’Malley, PhD, professor of neurobiology in the Department of Anatomy and Neurobiology at the School of Medicine. His thesis focused Fragile X syndrome, the most common form of inherited mental retardation.

Fragile X syndrome is caused by a deficiency of a protein called FMRP, and FMRP is known to oppose the functions of a receptor called mGluR5. One of the hallmarks of Fragile X syndrome is exaggerated mGluR5 signaling in the absence of FMRP. Blocking mGluR5 protects mice against the effects of the missing protein, and thus mGluR5 is an important therapeutic target for Fragile X syndrome.

In O’Malley’s lab, Fahey studied the role of intracellular mGluR5 in opposing FMRP function. A better understanding of this role will help unravel signaling pathways associated with Fragile X syndrome and related disorders.

Fahey plans to enter a dual-degree MD/PhD program at Baylor Medical School in the fall.

As part of the biology department’s recognition of his outstanding work, Fahey will be recognized at the Biology Honors Reception at 3:30 p.m. Wednesday, May 16, in McDonnell Hall, Room 162.

Prestigious national scholarships awarded to five WUSTL juniors

2012-04-23 00:00:00

Five juniors at Washington University in St. Louis have been awarded prestigious national scholarships.

Three students received the Barry M. Goldwater Scholarship and two students received the Morris K. Udall Scholarship for the 2012-13 academic year.

Winners of the Goldwater Scholarship are Rachel Greenstein, a biology major; Jennifer Head, who is majoring in chemical engineering; and Jenny Liu, who is majoring in electrical and biomedical engineering.

Madeleine Daepp, majoring in economics and mathematics, and Jeremy Pivor, majoring in environmental biology with a minor in public health, won the Udall Scholarship.

Daepp recently learned that she has also won a Truman scholarship.

“I believe the success of our students in winning these extremely competitive national awards is really grounded in the excellent faculty mentoring each of these students has received from very early on in their undergraduate careers,” says Joy Z. Kiefer, PhD, assistant dean in the College of Arts & Sciences and director of the Office of Undergraduate Research.

“This in-depth faculty mentoring is a hallmark of the undergraduate experience here at Washington University, and I am very happy to have us represented so well on the national stage,” says Kiefer, the campus fellowship adviser for current students and recent alumni interested in competitive fellowship and scholarship programs.

The Goldwater Scholarship is considered one of the most prestigious awards for undergraduates planning careers in the sciences, engineering or math. It covers as much as $7,500 annually toward tuition, fees and books for either one or two years.

The U.S. Congress established the Barry M. Goldwater Scholarship and Excellence in Education Foundation in 1986 to honor Sen. Barry M. Goldwater, who served in the U.S. Senate for 30 years.

The Goldwater Foundation, a federally endowed agency, awarded 282 scholarships for the 2012-13 academic year, selecting recipients on the basis of academic merit from a pool of 1,123 undergraduate sophomores and juniors nominated by the faculties of colleges and universities nationwide.

Udall scholarships are granted to those who demonstrate a commitment to fields related to the environment or to Native American or native Alaskan students in fields related to health care and tribal public policy.

It covers tuition, fees, books and room and board to a maximum of $5,000 per year.

The U.S. Congress established the Morris K. Udall Foundation in 1992 to honor Morris K. Udall, who served in the House of Representatives for 30 years, and renamed it in 2009 to include Stewart L. Udall in recognition of his public service.

The Udall Scholarship program is administered by the Morris K. Udall and Stuewart L. Udall Scholarship and Excellence in National Environmental Policy Foundation.

A total of 80 Udall Scholars were selected from 585 candidates nominated by 274 colleges and universities this year.

Goldwater Scholars

Greenstein is majoring in biology with a concentration in the areas of molecular biology and biochemistry in Arts & Sciences.

She has worked in the laboratory of Douglas Chalker, PhD, associate professor of biology, since 2010. Under his mentorship, she is studying the ciliate Tetrahymena thermophila, an organism that eliminates 30 percent of the DNA from its functional genome during development. The goal of Chalker’s lab is to understand how this massive genome reorganization is regulated and how it is related to DNA packaging in organisms with membrane-bound nuclei.

Greenstein’s contribution was to tag one of the genes suspected of playing a role in the reorganization with a fluorescent protein. She says she felt pure elation when she flipped off the light on her microscope, opened the filter and saw brilliant red dots in the nuclei of the cells, indicating the tagged protein was indeed localized to sites of DNA rearrangement.

She won a research fellowship from the Howard Hughes Medical Institute to continue her research during the summer of 2011. Working fulltime, she added other tags to serve as handles for biochemical analyses and worked on a "knockout" strain that would be missing the gene she had earlier tagged. (Knocking out a gene can show whether it is essential for cell survival or clarify its role in cellular processes.)

Greenstein, who is motivated in part by the early death of her mother from breast cancer, plans to earn a doctorate in molecular cell biology with the goal of teaching at the university level, a goal only reinforced by her experiences as a teaching assistant and peer tutor for the introductory biology courses at the university.

Head, a Danforth, Ervin and McKelvey Research scholar, is majoring in chemical engineering with minors in environmental engineering and Spanish in Arts & Sciences. McKelvey Scholars, selected from incoming engineering students, each receive an award to conduct research with a WUSTL faculty member in engineering, medicine or the sciences.

Head

Head worked with Yinjie Tang, PhD, the Francis Ahmann Career Development Assistant Professor in Energy, Environmental and Chemical Engineering. In his lab, she measured the toxicity of nanoparticles by their effects on seed germination and root elongation.

In summer 2010, as part of the International Experience Program offered by the Department of Energy, Environmental, and Chemical Engineering, Head studied environmental engineering at the Institute of Technology in Mumbai, India. During the program, she completed independent research projects on generating water from the atmosphere and microbial fuel cells.

The past two summers, Head has worked at the U.S. Environmental Protection Agency in Cincinnati. Under the guidance of Todd Luxton, PhD, a postdoctoral fellow at the EPA lab, she studied the use of iron nanoparticles from welding fumes to absorb and reduce hexavalent chromium in groundwater.

She also analyzed soil from a superfund site in North Carolina for arsenic and lead. At the EPA’s Experimental Stream Facility, she assisted in experiments to determine the effect of mountaintop mining on water systems.

This summer, Head plans to work with Daren Chen, PhD, professor of energy, environmental and chemical engineering, to generate nano-sized controlled-release cancer drugs by the electrospray technique Chen has perfected.

Head is the fundraising officer for the WUSTL chapter of Engineers Without Borders and will be the project leader for the chapter’s Ethiopia project in the upcoming school year. The group plans to rebuild a water tower for the Mekelle School for the Blind in Ethiopia.

Liu, an Alexander S. Langsdorf Fellow and a McKelvey Research Scholar, is majoring in electrical engineering and biomedical engineering.

Liu

The McKelvey scholarship, she says, allows her to work in a lab while attending school.

Recently, she studied the thermodynamics of a membrane protein in the bacterium E. coli under the guidance of Katie Henzler-Wildman, PhD, assistant professor of biochemistry and biophysics in the School of Medicine. The protein is a multidrug transporter that can recognize and expel multiple compounds, many of which are antibiotics, such as tetracycline.

Liu says she became interested in drug resistance during a summer internship in a pathology department while she was in high school. “Reading through patient charts describing infection from bacteria strains resistant to pretty much everything available, resulting in amputation or death, was heartbreaking,” she says.

Last May, Liu joined a completely student-run lab started by Sam Fok, who has since graduated, and advised by Eric C. Leuthardt, MD, assistant professor of neurosurgery, of biomedical engineering and of neurobiology in the School of Medicine.

The primary goal of the group is to work on the Ipsihand, a stroke rehabilitation therapy device that uses signals from motor neurons that survived the stroke to move the patient’s hand.

Outside the classroom, Liu builds combat robots with the student chapter of the American Society of Mechanical Engineers, for which she is co-secretary. She is also an officer for the International Pre-health Society, a WUSTL group that supports international students in their pursuit of health careers.

Udall Scholars
Daepp, who is majoring in economics and in mathematics, both in Arts & Sciences, plans to earn a law degree before embarking on a joint master’s degree program in agricultural law and economics, with the expectation of working in agricultural policy. Daepp was also named a Truman Scholar.

Daepp

“I would really like to mediate between farmers, researchers and policymakers to encourage the innovation and implementation of more sustainable food production practices,” she says.

As co-president of Burning Kumquat, a student-run garden, Daepp has led many efforts on campus and in the St. Louis community to raise awareness about the economic and environmental issues surrounding food production. She worked with members of the university administration and food service to supply produce from the student garden to the dining facilities and to facilitate a university farmer’s market for the campus community during the growing season.

She also secured the competitive Gephardt Institute for Public Service Civic Engagement grant to fund an environmental education and gardening project for inner-city youth in St. Louis.

She attributes her interest in sustainable food to her father. Both of her parents are mathematicians at Bucknell University in Lewisburg, Pa., but her father, who is from Bern, Switzerland, was raised in a culture where produce was eaten fresh and only in season.

Pivor plans to pursue advanced degrees in ocean policy and international environmental law with the goal of becoming an advocate for the sustainable conservation and management of the world’s oceans.

Pivor

A Florence Moog Scholar, Pivor is also a member of the WUSTL’s Pathfinder Program in Environmental Sustainability, a four-year educational program that allows students to examine the issues surrounding environmental sustainability through case studies and field trips.

Pivor has also studied the ecosystems of caves in Missouri, oyster reefs in North Carolina, and coral reefs in Madagascar.

Pivor co-founded Washington University Students for International Collaboration on the Environment (WUSICE). Through WUSICE, he organized WUSTL’s first U.S.-China Undergraduate Conference on Climate Change and Sustainability, inviting students from Fudan University in Shanghai, China, to St. Louis to discuss climate change.

Last fall, Pivor organized the university’s first delegation to the United Nations COP17 climate-change conference in Durban, South Africa, where he also served as the Sierra Club’s student coalition’s international youth delegate. (COP17 stands for the 17th Conference of the Parties to the United Nations Framework Convention on Climate Change.)

Engineers receive annual achievement awards

2012-04-23 00:00:00

Seven distinguished alumni and a former dean of the School of Engineering & Applied Science at Washington University in St. Louis were honored at a dinner April 19 at the Coronado Ballroom.

Six received Alumni Achievement Awards, one a Young Alumni Award, and the former dean received the Dean’s award.

The honorees:

Larry Chiang (SI ’73, SI '75)

Chiang

Chiang worked at at Bell Laboratories and for several American companies, before returning to Taiwan in 1985.

As the vice president of sales and engineering of Siemens Telecommunications in Taiwan, Chiang participated in the digitalization of the company’s analog telecommunications network. He was promoted to executive vice president and established a joint venture with Fujitsu for fiber optical products in 1992.

As president of Siemens Telecommunication in 1995, Chiang participated in the design, delivery and commissioning of two GSM mobile networks.

Chiang retired in 2005 and became a senior advisor at Siemens Telecommunications. Today, he works as an investment consultant and supervises a venture capital fund.

To show his appreciation of research assistantships he received while attending graduate school, he established an endowed scholarship ata WUSTL. He also provides scholarships for students in China.

For a video tribute to Chiang, click here.

Richard Janis (SI ’74, GA '74)

Janis

As a professional engineer, registered architect and president of William Tao & Associates, Janis leads building projects both in St. Louis and around the world.

In 2005, Janis was engineer of record and LEED accredited professional for WUSTL's first LEED-accredited building, Earth & Planetary Sciences (now Rudolph Hall). More recently, he led the engineering design of the School of Medicine's LEED Gold Data Center.

Janis earned a bachelor's degree in mechanical engineering from the University of Missouri-Rolla (now Missouri University of Science & Technology) in 1968. He earned master's degrees in architecture and mechanical engineering at WUSTL in 1974.

Janis went to work with William Tao & Associates, a practice devoted to energy-effective design of buildings. When Tao retired in 1989, Janis became CEO. The firm continued to maintain an industry leadership role in design, growing to include many different engineering services.

Janis has participated in many professional organizations, including the American Institute of Architects and United States Green Building Council, where he served on the executive committee. He is also a past president of the St. Louis chapter of the International Facility Management Association (IFMA).

A senior lecturer for the School of Architecture, Janis has taught at WUSTL since 1976. He is also an adjunct instructor for the School of Engineering & Applied Science where he teaches sustainable systems design. He is coauthor, with Bill Tao, of Mechanical and Electrical Systems in Buildings, soon to be in its fifth edition.

For a video tribute to Janis, click here.

Deepak Kantawala (SI ’63, SI’ 66)

Kantawala

Kantawala currently serves as a consultant to India’s Central Pollution Control Board, with responsibility for reviewing water-quality criteria and standards for India’s fresh, marine and ground waters.

He has been involved in the design and commissioning of more than 100 industrial wastewater treatment plants for various industry subsectors, such as pharmaceuticals and pesticides, and for companies ranging from NOCIL (Shell), to Monsanto.

He also participated in the design and commissioning of effluent treatment plants for industrial estates and of sewage treatment plants.

Kantawala earned a bachelor's degree in civil engineering from the University of Bombay in 1960, and then moved to the United States to attend WUSTL, where he earned master's and doctor of science degrees in environmental and sanitary engineering in 1963 and 1966, respectively.

Kantawala was the recipient of Institution of Engineers (India) Environmental Engineering Design Award for the year 1989-90. In 2000, he was presented with the Chemtech Foundation Chemical Industry Stalwart Award.

He is a member of the American Academy of Environmental Engineers and has served in various capacities for the World Bank, World Health Organization, USAID and the government of the Netherlands.

He served as chairman of India’s Research Council of the National Environmental Engineering Research Institute from 1994-97. He is a member of the Water Environment Federation and of India’s Institution of Engineers, a life member of the Indian Water Works Association and pf the Indian Association of Environmental Management, and president of the Indian Environmental Association.

For a video tribute to Kantawala, click here.

Janice Karty (EN ’78)

Karty

After earning a bachelor’s in engineering in 1978, Karty went on to earn master's and doctoral degrees from Rice University in 1981 and 1983, respectively. In 1985, she joined McDonnell Douglas Astronautics Company (now Boeing), as a research scientist

Karty currently serves as a technical fellow within Boeing Defense, Space and Security. Since 2010, she has worked on electromagnetic environmental effects (known as E3) for products such as the F/A-18E/F Super Hornet, the F-15, and the T-45 Training System.

During her 27-year career at Boeing, she has established a record of sustained technical excellence. She was elected to be a Boeing associate technical fellow in 2001, and named a technical fellow five years later.

Karty is a frequent guest lecturer at WUSTL as well as a local science fair judge. She often visits area high schools to speak about careers in engineering and the sciences.

For a video tribute to Karty, click here.

Milind Kulkarni (SI ’96, PMBA ’08)

Kulkarni

Kulkarni serves as vice president and chief technology officer of solar materials and quantitative silicon research at MEMC Electronic Materials.

In this role, he directs cross-functional research on polysilicon production, continuous Czochralski growth, directional solidification, wafering and cleaning processes, solar cell technology and module production.

After earning a bachelor's degree in chemical engineering from the University of Mumbai, Kulkarni moved to the United States, where he earned a master's degree from Oregon State University and a doctoral degree from WUSTL, both in chemical engineering. He later earned a master's degree in business administration at WUSTL as well.

In 2005, Kulkarni became a senior fellow in MEMC, the highest technical recognition offered by the company. In 2009 he became a vice president. In 2011 he was named chief technology officer.

Kulkarni developed unifying theories to describe polishing and decorating etchants, developed a novel silicon-etching process, explained the unique defect distributions near the periphery of defect-engineered silicon crystals, and developed key mathematical tools and process insights to enable defect engineering of Czochralski silicon crystals.

He has also guided improvements in the methods used to produce polysilicon and crystalline silicon, and in wafering technologies for making solar cells.

The author of two book chapters, two award-winning journal papers and many other publications, Kulkarni serves as a reviewer for several professional journals in his field.

For a video tribute to Kulkarni, click here.

James McKelvey, Jr. (EN ’87, LA ’87)

McKelvey

McKelvey is an engineer, artist and entrepreneur. As an undergraduate engineer at WUSTL, McKelvey wrote two computer programming textbooks. After graduation he took a job with IBM and a side position as a teaching assistant in glassblowing.

In 1990, he co-founded Mira Digital Publishing, which is today a leader in electronic publishing for scientific conferences.

In 2000, he co-founded Third Degree Glass Factory, one of the most successful glassblowing schools in the world. He also wrote The Art of Fire: Beginning Glassblowing, the leading textbook for novice glassblowers.

In 2009, McKelvey co-founded Square, one of the fastest-growing technology companies in the U.S., which enables anyone to take credit card payments anywhere using their mobile device. McKelvey now sits on the board of directors of Square.

For a video tribute to McKelvey, click here.

Jennifer Dionne (EN ’03, EN ’03)

Dionne

Dionne, the recipient of the Young Alumni Award, is currently an assistant professor in the Department of Materials Science & Engineering at Stanford University.

Her research investigates metamaterials — engineered materials with optical and electrical properties not found in nature — for applications ranging from enhanced solar energy generation to subwavelength optical imaging and nanophotonic manipulation.

Dionne earned a bachelor's of science degree in systems science & engineering and physics in 2003 from WUSTL. She earned a doctoral degree in applied physics in 2009 from the California Institute of Technology.

The recipient of many young investigator achievements, she has won the NSF CAREER Award (2012), the AFOSR Young Investigator Award (2011), Technology Review’s Top Young Innovator Award (2011), the Hellman Fellowship (2011), the Terman Fellowship (2010), the Clauser Prize for Best Caltech Thesis (2009) and the MRS Gold Medal Graduate Student Award (2008).

She is the author of Introduction to Solar Photonics and one of the organizers of a science-as-art exhibit, "NanoArt: More than Meets the Eye."

For a video tribute to Dionne, click here.

Salvatore Sutera

Sutera

Sutera, the recipient of the Dean’s Award, came to WUSTL in 1968 to serve as the chair of the Mechanical Engineering Department, a post he held for 25 years. Sutera was instrumental in the creatopm pf undergraduate degree program in biomedical engineering.

He earned a bachelor's degree in mechanical engineering from The Johns Hopkins University in 1954 and a master of science in mechanical engineering from the California Institute of Technology in 1955. He spent the following year as a Fulbright Fellow in Paris, France.

Following a year with the DuPont Corp. in Delaware, Sutera returned to Caltech and earned a doctoral degree in 1960. From 1960 to 1968, he was a member of the engineering faculty at Brown University.

Early in his academic career, Sutera began to focus his research on biomechanics. He and his collaborators made many contributions to the understanding of blood flow in the mammalian microcirculation, flow-induced trauma to blood in artificial organs, and the mechanical properties of the red blood cell in health and disease.

A dedicated Francophile, Sutera spent a semester as a visiting professor at the University of Paris in 1973. He has been an active member of the Alliance Française of St. Louis for more than 20 years and has served on the board of directors of St. Louis-Lyon Sister Cities Inc.

For a video tribute to Sutera, click here.

Elgin, Templeton elected to American Academy of Arts and Sciences

2012-04-19 00:00:00

Two Washington University in St. Louis professors have been elected fellows of the American Academy of Arts and Sciences.

The new fellows are Sarah C.R. Elgin, PhD, the Viktor Hamburger Professor of Arts & Sciences; and Alan R. Templeton, PhD, the Charles Rebstock Professor of Biology in Arts & Sciences.

“I am delighted to have two of our outstanding faculty receive this tremendous honor,” says Chancellor Mark S. Wrighton. “Professors Elgin and Templeton are two dedicated scholars, and this recognition is well-deserved. This achievement symbolizes the good fortune we have had at Washington University in attracting premier faculty.”

Elgin and Templeton are among 220 American men and women elected as fellows this year by the academy, an organization formed in 1780 to cultivate the arts and sciences and to recognize leadership in scholarship, business, the arts and public affairs.

The academy’s current membership includes more than 250 Nobel laureates and 60 Pulitzer Prize winners. Fellows are selected through a competitive process that recognizes individuals who have made pre-eminent contributions to their disciplines and to society at large.

This year’s new fellows and foreign honorary members will be welcomed during an Oct. 6 induction ceremony at the academy’s headquarters in Cambridge, Mass.

Elgin

James Kegley for HHMI

Elgin

Elgin joined the Department of Biology in 1981 and became a full professor in 1984. She was installed as the inaugural Viktor Hamburger Distinguished Professor in Arts & Sciences in 2006.

Besides her primary appointment in biology, Elgin holds joint appointments as professor of education in Arts & Sciences; and as professor of biochemistry and molecular biophysics and professor of genetics in the School of Medicine.

Her research focuses on the role of chromatin structure in regulating fruit fly (Drosophila) genes. (Chromatin is the complex of DNA and proteins that coil into chromosomes at some stages of the cell cycle.)

Her laboratory has developed a number of approaches that have contributed to the understanding of how DNA is packaged in the nucleus, including how critical regulatory regions are maintained in an accessible form.

Her current focus is on heterochromatin structure and gene silencing. (Heterochromatin is a tightly packed form of DNA that is largely inaccessible to the machinery of the cell needed for gene expression.) Her lab identified HP1, a critical protein for heterochromatin formation that has been conserved from the yeast S. pombe to man.

Studies of the small fourth chromosome in the Drosophila genome have highlighted the importance of repetitious elements (fragments of retroviruses and DNA transposons that invade our genomes) in determining which regions of the genome should be silenced and have suggested that an RNAi-based mechanism is critical for HP1 deposition and silencing of the repeats.

In the late 1980s, Elgin started working with the University City School District in a science education partnership, which has since expanded to create the Office of Science Outreach, whose mission is to serve K-12 students and their teachers through creative curriculum development and teacher professional development activities. The office now is part of the Institute for School Partnership, directed by Victoria May.

In 2002, Elgin became a Howard Hughes Medical Institute Professor with the ambition of developing core curriculum that would integrate primary research in genomics with a college course. This project has been expanded and disseminated as the Genomics Education Partnership, a consortium of more than 80 college and university faculty who are engaging their students in sequence improvement and annotation projects with the goal of publishing the results in primary research journals.

Elgin got off to a flying start, studying fallout in Oregon rainwater from Soviet nuclear weapons tests while still in high school. She earned a bachelor’s degree in chemistry from Pomona College in 1967. While at Pomona, she participated in a summer research program at the University of Leeds characterizing the egg stalk of the green lacewing fly Chrysopa vittata.

Elgin earned a doctorate in biochemistry from the California Institute of Technology (Caltech) in 1971, where her thesis concerned nonhistone chromosomal proteins, examining primarily rat tissues.

After postdoctoral work at Caltech, Elgin joined the faculty at Harvard University, where her lab pioneered immunostaining of polytene chromosomes from Drosophila larval salivary glands and the use of nuclease digestion assays to analyze chromatin structure at specific genes. (Polytene chromosomes are giant chromosomes produced when DNA is replicated but the cell doesn’t divide.) She moved from Harvard to WUSTL eight years later.

Elgin has served on the editorial boards of many of the distinguished journals in her field. She also was founding co-editor in chief of CBE-Life Science Education, where she remains a senior editor.

She has been named an "Outstanding St. Louis Scientist" by the St. Louis Academy of Science and was presented with WUSTL’s Distinguished Faculty Award in 1993.

Elgin has received numerous awards for her outstanding service to students.

In 2004, then-Missouri Governor Bob Holden presented her with a Governor's Award for Excellence in Teaching. Arts & Sciences students have twice presented her with a faculty award for her involvement in fostering students’ academic development and research opportunities.

In December 2006, she received the Bruce Alberts Science Education Award from the American Society for Cell Biology; in May 2007, she received the Award for Exemplary Contributions to Education from the American Society for Biochemistry and Molecular Biology; and in 2009, she received the Genetics Society of America’s Elizabeth W. Jones Award for Excellence in Education.

Templeton

Templeton

Templeton joined the WUSTL faculty in 1977 as an associate professor in the Department of Biology in Arts & Sciences and in the Department of Genetics in the School of Medicine. He soon became a professor both of biology and of genetics and, in 2001, he was named the Charles Rebstock Professor of Biology.

In addition to his primary appointment as professor of biology, he currently is a research associate of the Missouri Botanical Garden, a professor of biomedical engineering in WUSTL’s School of Engineering & Applied Science, a visiting professor at the Technion in Israel, a professor in the division of statistical genomics at WUSTL’s School of Medicine, and a professor (part-time) at the University of Haifa in Israel.

Templeton’s work involves the application of molecular genetic techniques and statistical population genetics to a variety of evolutionary problems, both basic and applied.

He takes an evolutionary approach to clinical genetics, including the study of the genetics of complex diseases, such as coronary artery disease and end-stage kidney disease.

He also applies evolutionary genetics to conservation biology, one focus being the impact of managed forest fires at the landscape level on the population structure of Ozark species, such as the Eastern collared lizard (Crotaphytus collaris collaris) and lichen grasshoppers (Trimerotropis saxatilis).

He also is studying the impact of human activities upon dispersal of the endangered fire salamander (Salamandra infraimmuculata) in Northern Israel and the wild ass in Southern Israel.

He is interested in basic questions about evolution, such as the meaning of "species" and the mechanisms by which new species evolve, and human evolution over the past two million years.

He is particularly well-known for work demonstrating that the genetic differences between humans populations are insufficient to define them as different races, using defintiions of race that are applied to other species.

According to Templeton’s research, perceived differences in races are more related to cultural perceptions and biases than any underlying genetic reality. For example, Templeton’s statistical analysis of the human genome shows that much greater genetic diversity exists between populations of chimpanzees than of humans.

Templeton earned a bachelor’s degree in zoology at WUSTL in 1969. He earned a master’s degree in statistics and a doctoral degree in human genetics at the University of Michigan, both in 1972.

He held positions at the University of Michigan, University of Hawaii, University of Texas at Austin and Universidade de São Paulo in Brazil before returning to St. Louis.

A fellow of the American Association for the Advancement of Science and of the Academy of Science of St. Louis, he has served as the editor or associate editor of many of the journals in his field, and his own articles have often been among the most highly cited for a given year.

He is perhaps proudest, however, of the awards he has received for helping protect endangered species. The St. Louis Zoological Garden twice won the Edward Bean Award for management programs he helped design, first for the Speke’s gazelle and then for the banteng/guar.

The Missouri Department of Conservation and the U.S. Forest Service have recognized his work in the Missouri Ozarks, which helped a number of endemic species as well as the collared lizard.

Nobel Laureate Ciechanover to speak April 27

2012-04-17 00:00:00

Aaron Ciechanover, MD, PhD, the Distinguished Research Professor at Technion-Israel Institute of Technology in Haifa, Israel, and co-recipient of the 2004 Nobel Prize in chemistry for his contributions to the discovery and description of a process cells use to discard unwanted proteins, will give a special seminar at Washington University in St. Louis Friday, April 27.

Ciechanover

His lecture, “The Ubiquitin Proteolytic System: From Basic Mechanisms Through Human Diseases and on to Drug Development,” will take place at 4 p.m. in the Laboratory Sciences Building, Room 300. The seminar is free and open to the public. A reception will follow.

Sixty years ago, Ciechanover says, body proteins were thought to be essentially stable molecules subject only to minor wear-and-tear, and the proteins we ate were thought to function solely as energy-providing fuel with little or no connection to body proteins.

We now realize, he says, that intracellular proteins turn over extensively, that the process is highly specific in most cases, and that the stability of many proteins is regulated individually and can vary under different conditions.

Regulated proteolysis serves numerous physiological functions, including maintaining the cellular quality control (by removing impaired proteins) and controlling essential processes (by removing, in a programmed and timed manner, different cellular regulators).

Ciechanover and his fellow laureates discovered the ubiquitin-proteasome system that removes damaged or unneeded proteins from the cell. The system marks proteins for destruction by tagging them with a small protein found in all cells called ubiquitin.

Once a protein has accumulated a chain of ubiquitin molecules, it is bound by the proteasome, the cell’s waste disposal system, which unfolds the protein and chops it up into building blocks to be used for the synthesis of new proteins.

Not surprisingly, aberrations in protein breakdown have been implicated in many diseases, among them many cancers, neurodegenerative diseases (Alzheimer’s, for example) and infectious and inflammatory diseases.

As a result, many pharmaceutical companies and research laboratories now are looking at the ubiquitin system as a target for novel drugs. One drug already on the market combats multiple myeloma, a form of blood cancer.

Ciechanover was born in Haifa, Israel, in October 1947, one month before Israel was recognized by the United Nations as an independent state. His parents had emigrated from Poland with their families as adolescents in the mid-1920s.

From his early days at home, he says, he remembers a strong encouragement to study. While his home was not a rich one, it had a huge library, and his parents had a great collection of classical music. He remembers that Bizet’s Carmen occupied more than 20 RCA 78-rpm bakelite records.

Even as a child, he was fascinated with biology. He collected flowers on Mount Carmel and dried them in his older brother’s heavy Babylonian Talmud. “I will never forget his rage on discovering my love of nature hidden within the pages of the old Jewish tracts,” he says.

Biology at the time was a largely descriptive discipline. Ciechanover remembers the effort invested in memorizing the 12 differences between the frog and the toad or between the circulatory systems and skeletal structure of the cat and the dog.

Since chemistry and physics appeared to him to be strong mechanistic disciplines built on solid mathematical foundations, he had a deep feeling that the future somehow resided in biology and in deciphering basic mechanisms, about which so little was then known.

“Yet the complexity of biological and pathological processes looked to me enormous,” he says, “almost beyond our ability to grasp, and I was intimidated.”

At first he pursued the safer route of training as a medical doctor, only to discover that medicine was even more descriptive than biology, and that because the understanding of disease was so shallow, doctors treated symptoms rather than causes.

In the end, he yielded to his attraction to the “magical and enchanting” field of biochemistry, abandoned medicine and enrolled in graduate school to begin a career in scientific research.

Between 1987-2001, Ciechanover repeatedly was a visiting professor at Washington University’s School of Medicine. In 2006, the university awarded him an honorary doctor of science degree.

For more information, contact Cindy Goessling at cgoessling@wustl.edu or (314) 935-9236.

Can behavior be controlled by genes? The case of honeybee work assignments

Diana Lutz — 2012-04-16 00:00:00

Travis Mohrman

Nurse bees tending to brood in cells both open and capped with beeswax. Recent work at Washington University in St. Louis suggests that the division of labor in honeybee colonies is controlled by small segments of noncoding RNA called micro-RNAs, or miRNAs.

What worker bees do depends on how old they are. A worker a few days old will become a nurse bee that devotes herself to feeding larvae (brood), secreting beeswax to seal the cells that contain brood and attending to the queen.

After about a week, she will progress to other tasks, such as grooming nest mates, ventilating the nest and packing pollen. Only at the end of her life will she become a forager, venturing forth to collect nectar and pollen for the colony.

Yehuda Ben-Shahar, PhD, assistant professor of biology in Arts & Sciences at Washington University in St. Louis, wondered if this highly stereotyped system of task allocation wasn’t somehow under genetic control.

In an article published in the advance online edition of Genes, Brain and Behavior April 6, he and colleagues from Washington University, the University of Delaware, the University of Illinois Urbana-Champaign and the Institute for System Biology in Seattle, demonstrate that the division of labor among honeybees coincides with the presence in their brains of tiny snippets of noncoding RNA, called micro-RNAs, or miRNAs, that suppress the expression of genes.

Forager bees that venture out to collect nectar and pollen have higher levels of some miRNAs in their brains than nurse bees that are devoted to tending to brood.

By comparing honeybee miRNAs to those of wasps, bees and ants, the scientists also showed that eusocial insects share many miRNAs that are absent in solitary insects. (Eusociality is an extreme form of social organization in which organisms care for young communally and give up reproductive rights to a queen.)

The pattern of conservation across species suggests that miRNAS, are important regulators of social behavior not just during the bee’s lifetime but also over evolutionary time.

Working for a living

Travis Mohrman

Worker bees become foragers only at the very end of their lives, after making their way through a list prescribed tasks from feeding brood to ventilating the nest. The forager in this photo is recognizable by her saddlebags, which are stuffed with yellow pollen.

Ben-Shahar chose the honeybee (Apis mellifera) as his model organism for the genetic control of behavior because the worker bees display such well-characterized division of labor.

Task allocation in honeybees is highly scripted, and yet the script is flexible enough to respond to labor shortages. If there aren’t enough nurse bees in the colony, nurses will stick with their tasks past the usual age limit, becoming what are called overage nurses. And if there aren’t enough foragers, bees too young for that role will rush to take it on, becoming precocious foragers.

For the scientists this plasticity makes bees a very powerful behavioral model. By comparing overage nurses to precocious foragers it is possible to compare gene expression in different behavioral states without the confounding factor of age.

A tiny off-switch

Ben-Shahar was curious about the role newly discovered molecules called miRNAs might play in the control of behavior.

Francis Crick, the co-discoverer of the structure of DNA, said in 1956 that the central dogma of biology is that DNA makes RNA makes protein — and protein then does the cell’s work, including activating other genes.

The central dogma still holds, but in the past 50 years it has been enormously complicated by the discovery of many mechanisms for regulating gene expression, including a proliferation of regulatory RNAs.

Among these are miRNAS, tiny snippets of noncoding RNA typically only 22 nucleotide units long that bind to RNA transcripts of a gene, reducing protein production and, in effect, silencing the gene.

Micro-RNAs are known to regulate development and disease processes such as cancer, Ben-Shahar says.

“We wondered if they weren’t playing a role in regulating social behaviors,” he says, “because recent studies have implicated them in complex nervous-system functions such as neurodevelopment, psychiatric disease, and circadian clocks.”

A library of possibilities

Because nobody knew much about the miRNAs in bees, Ben-Shahar and the paper’s first author, undergraduate student Jacob Greenberg (now a medical student at WUSTL's School of Medicine), decided to make a grand survey of the miRNA “library” in a bee’s head.

They ground up heads, extracted the RNA from the tissue, sorted out the small RNA fragments, and sent those to a company that sequences DNA (or RNA, which is a similar molecule).

Because the entire honeybee genome has been sequenced, the short sequences the company supplied could be compared with the bee genome and non-matching sequences discarded as junk.

Various criteria were applied to the remaining sequences to whittle the candidates down to true miRNAs.

All of this sorting and sifting was done in collaboration with Weixiong Zhang, PhD, professor of computer science and engineering in the School of Engineering & Applied Science, who is an expert in computational biology.

“Zhang’s lab has a lot of experience doing the bioinformatics part, which is important because not every little snippet of RNA is a miRNA; there are certain criteria they use to prove it’s an miRNA,” says Ben-Shahar.

At the end of this monumental cataloguing effort, the scientists had a list of 97 miRNAs that are expressed in the heads of honeybees, including 17 that had never been identified before, and many others that had been found in flies and mammals but not in bees.

Five prime suspects

To design a manageable behavioral experiment, the scientists then selected five of the 97 miRNAs for closer inspection. These five were either very abundant or had been implicated in neural function in other organisms.

The scientists then manipulated two colonies of bees to produce cohorts of nurse and forager bees that were the same age, either young for foragers or old for nurses.

They dissected out the brains of their precocious foragers and overage nurses and measured the level of expression of the miRNAs in the brains with a sensitive test called the Northern Blot.

“We found that the level of expression of four of these miRNAS correlated with the task the bee was performing. Four of them were expressed at higher levels in foragers than in nurses. Because miRNAs typically suppress gene expression, this means genes actively transcribed in nurses were silenced in foragers,” Ben-Shahar says.

“There is clearly a task-related difference, but we don’t yet know what the gene targets of the miRNAs are,” he says.

An ancient regulatory system

Could miRNAs be playing a much broader role in the behavior of bees, not just regulating the tasks workers performed but also their social behavior more generally?

Honeybees are eusocial insects, meaning that a colony behaves more like a superorganism than a gathering of individuals. The scientists knew that the genomes of several other eusocial insects had recently been sequenced.

Did the eusocial insects share miRNAs, they wondered?

The grand survey of miRNAs had identified 20 miRNAs that seemed to be honeybee-specific. To test their idea, they looked for these miRNAs in the genomes of four other eusocial insects within the hymenoptera (an order of insects that consists of ants, bees and wasps) and in that of a solitary wasp.

A total of 19 out of the 20 miRNAs that had initially appeared to be honeybee-specific were also identified in the genomes of the other eusocial insects. Moreover, five found in all the eusocial hymenoptera were found in no other species. And none of the 20 miRNAS found in the eusocial insects were found in the genome of the solitary wasp.

Ben-Shahar

Twenty miRNAs the scientists originally thought to be specific to honeybees turned out to be common to other eusocial insects as well, a pattern consistent with the idea that miRNAs played a role in the evolution of eusociality. The honeybee miRNAs (green) are also found in: Apis floria, the Asian dwarf bee; Bombus terrestris, the bumble bee; Atta cephalotes, the leaf cutter ant; and Camponotus floridanus, a carpenter ant. All of these are social insects, although the last three are considered to be “primitive social.” In contrast the miRNAs are completely absent in Nasonia longicornis, a solitary wasp. (Yellow indicates an imperfect match.)

Once a miRNA assumes a functional role it is rarely lost from an animal’s genome, Ben-Shahar says, because it typically regulates multiple genes and is too thoroughly enmeshed in the cell’s regulation to be easily extracted. This makes miRNAs a valuable marker for evolutionary relationships among species.

The relationships among eusocial species could do with clarification. Ants and bees diverged a long time ago, and all ant species are eusocial, but bee species run the gamut from solitary to eusocial.

That pattern makes sense, Ben-Shahar says, only if the eusocial trait evolved more than once as new species evolved. Something in hymenoptera DNA may have made that group of animals more sensitive than others to whatever evolutionary pressures led to social behavior, he says.

Genetic control of human behavior is undoubtedly more complicated, Ben-Shahar says, but he points out that the human genome encodes close to 2,000 miRNAS, including two of the five he studied in bee brains, and these 2,000 miRNAs are thought to target roughly 60 percent of our genes.

MacMahon to receive 2012 Stalker Award

2012-04-12 00:00:00

Mara MacMahon has been selected to receive the 2012 Harrison D. Stalker Award from the Department of Biology in Arts & Sciences at Washington University in St. Louis.

The award is named in honor of the late Harrison D. Stalker, PhD, who was a member of the biology faculty from 1942-1982, a world-renowned evolutionary biologist, an inspired teacher and an enthusiastic supporter of the fine arts.

whitney curtis

MacMahon with some of her creations.

The award is given annually to a graduating biology major whose undergraduate career has been marked by outstanding scientific scholarship and contributions to the university in the areas of artistic expression or community service.

MacMahon exemplifies the spirit of the Stalker Award exceptionally well: as a five-year, combined-degree candidate, she is earning both a bachelor of arts in biology (with an emphasis on human and comparative anatomy) and a bachelor of fine arts in communication design (with an emphasis on 3D computer animation). Throughout her course of study, she has been a fixture on the Sam Fox School’s dean’s list.

She also has combined her scientific and artistic skills in creative ways on her own initiative. In an independent study with Jane Phillips-Conroy, PhD, professor of physical anthropology in the Department of Anthropology in Arts & Sciences and of anatomy and neurobiology in the School of Medicine, she shadowed medical students in the human anatomy lab, observing and sketching during dissections, paying particular attention to the bones and muscles that move limbs.

MacMahon went on to serve as a teaching assistant in the vertebrate structure course in the biology department, supplementing the students’ study guides with her own sketches.

Meanwhile, she also served as a teaching assistant in the Sam Fox School for students studying 3D animation at both the introductory level and as advanced, independent-study participants.

Her unusual combination of scientific and artistic skills won her two exceptionally competitive summer internships: one at Pixar Animation Studios in 2010, and the other at the Walt Disney Animation Studios in 2011. In these internships, she was able to use her knowledge of anatomy to “rig” characters to move in realistic ways.

For her senior seminar in art, she produced a short film illustrating one of the classic tales of Greek mythology: the hunt for the fearsome Caledonian boar.

In addition to English (her native tongue), MacMahon is fluent in Mandarin Chinese, conversational Italian and elementary Spanish. And throughout her time at WUSTL, she has been associated with Women’s Club Soccer, the university's women’s club soccer team, serving as an assistant manager, student trainer and treasurer. Soccer, she says, has been a welcome release from her studies. She also worked with varsity athletes as a student trainer.

Following graduation, MacMahon hopes to establish a career in the film industry, either in computer animation or in special effects.

Arts & Sciences junior named Newman Civic Fellow

2012-04-02 00:00:00

Tej Azad, a junior in Arts & Sciences at Washington University in St. Louis, was among 162 students from across the country named a Newman Civic Fellow for 2012 by Campus Compact.

Azad

The Newman Civic Fellows Awards recognize inspiring college student leaders who have demonstrated an investment in finding solutions for challenges facing communities throughout the country and the world.

“Azad is an outstanding example of a civic leader,” says Chancellor Mark S. Wrighton, who nominated him for the award.

“He analyzed the needs of the community, was committed to raising awareness of those needs through the power of education and inspired others to join him in seeking solutions. I believe he exemplifies all that this prestigious honor represents.”

Azad was selected as a Newman Civic Fellow for his dedication to addressing health disparities through education. As a leader for WashU H.O.P.E. (HIV/AIDS Outreach, Prevention, and Education), he strives to address the stigma surrounding HIV.

In this role, he has tutored children living in an alternative housing facility for families affected by HIV. Under his leadership, the number of volunteers for WashU H.O.P.E. increased five-fold.

Azad also partnered with a medical student group, S.T.A.T.S. (Students Teaching AIDS to Students), to teach high school students about HIV biology and prevention, again encouraging much-increased participation in the program.

He was a co-organizer for World AIDS Day 2011 on the WUSTL campus and is a member of the local HIV Youth Advocacy Committee that seeks to allow the voice of young people in St. Louis to be heard in the dialogue on HIV.

Through WUSTL’s Social Justice Center, Azad developed an interest in urban nutrition and learned about urban “food deserts.”

Azad plans to work with a national organization to bring a mobile produce market to St. Louis. In this model, the mobile market would transport fresh produce to areas in St. Louis with limited access to these foods. The issue of food disparities has become a passion for him, and he intends to work on the mobile market initiative beginning this summer.

A John B. Ervin Scholar, Azad is majoring in biology-neuroscience with a minor in philosophy-neuroscience-psychology.

He has helped recruit participants in an imaging study to assess the effects of chronic HIV on cognitive abilities for in the laboratory of Beau Mark Ances, PhD, assistant professor of neurology in the School of Medicine, and has done research on the molecular biology of stroke in the laboratory of Gregory Joseph Zipfel, PhD, associate professor of neurological surgery, also in the School of Medicine. He plans to pursue a career in medicine.

The 2012 Newman Civic Fellows were nominated by college and university presidents from 32 states across the country. Through the Newman Civic Fellows Awards, college and university presidents acknowledge students with the ability and motivation to create lasting change through service, research and advocacy.

“These students represent the next generation of public problem solvers and civic leaders,” says Campus Compact Board Chair James B. Dworkin, chancellor at Purdue University North Center. “They serve as national examples of the role that higher education can — and does — play in building a better world.”

Through service-learning courses and other opportunities for community engagement, colleges are developing students’ critical public problem-solving skills, such as the ability to analyze community needs, a willingness to participate in public processes and debate, the commitment to raise awareness about challenges and the ability to inspire people to become part of solutions.

Campus Compact is a national coalition of almost 1,200 college and university presidents — representing some 6 million students — who are committed to fulfilling the civic purposes of higher education to improve community life and to educate students for civic and social responsibility.

The award is named after Frank Newman, PhD, a founder of Campus Compact who had an impact on American education and its role in the development of citizens who are eager and prepared to make a difference. He dedicated his life to creating systemic change through education reform.

For more information about the Newman Civic Fellows, visit compact.org.

Early-stage lung cancer treatments evaluated in patients with breathing problems

Caroline Arbanas — 2012-04-09 00:00:00

Jeffrey Bradley, MD

A CT image shows an early-stage lung tumor. A new clinical trial will evaluate whether a limited surgical procedure or a specialized type of radiation therapy is the best treatment for patients with early-stage lung cancer who also have breathing problems.

The Alvin J. Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine is seeking patients for a clinical study to determine the best treatment for patients with early-stage lung cancer who also have breathing problems.

Many patients with early-stage lung cancer have emphysema, pulmonary hypertension or other breathing problems that limit their treatment options.

The study focuses on patients with the most common type of lung cancer, non-small cell lung cancer. When it is diagnosed early, the standard treatment is surgery. But the operation is especially risky for patients with poor lung function, who often have complications after surgery.

In the new trial, doctors will compare a type of radiation therapy, called stereotactic body radiation therapy, to a more limited surgical procedure. Rather than remove the entire section of the lung, surgeons will remove only a small portion, which may reduce complications after surgery.

Stereotactic body radiation therapy pinpoints high doses of radiation directly to the tumor, while reducing damage to surrounding tissues. It can also be delivered in just several treatments over seven to 10 days, compared to conventional radiation, where treatment is given over six to eight weeks.

Stereotactic body radiation therapy is the treatment of choice for patients with non-small cell lung cancer who are too frail for any surgery. But doctors don’t know whether it is better than the limited surgery for patients healthy enough for surgery but who have decreased lung function.

“Our hope is that doctors and patients will embrace this cutting-edge trial so we can clarify the optimal treatment for this group of higher-risk patients,” says study co-investigator Bryan F. Meyers, MD, chief of the Section of Thoracic Surgery. “For very frail patients, we have stereotactic body radiation therapy. For fit patients, surgery still dominates. This trial looks at people on the cusp for whom we don’t have certainty.”

Nationwide, an estimated 420 patients will be enrolled in the trial, which is sponsored by the National Cancer Institute. Traves Crabtree, MD, assistant professor of surgery, is the local principal investigator of the study.

To be eligible, patients must have an early-stage (1A or selected 1B) non-small cell lung tumor and not received other cancer treatments.
Siteman Cancer Center was involved in an earlier trial of stereotactic body radiation therapy for early-stage non-small cell lung cancer in patients too frail for surgery.

“We have one of the largest U.S. experiences with stereotactic body radiation therapy for lung cancer,” says study co-investigator Jeffrey Bradley, MD, professor of radiation oncology. “It can eradicate lung tumors in 90-95 percent of patients with early-stage cancer, double that of conventional radiation therapy. And stereotactic body radiation therapy also appears to double the survival rate in these patients, compared to conventional radiation therapy. It’s definitely a major advance in lung cancer treatment.”

Patients in the study will be randomly assigned to receive either three treatments of stereotactic body radiation therapy over seven to 10 days or the limited surgical procedure. Over the next five years, doctors will evaluate patients’ survival rates and their quality of life after treatment.

For more information about the study, call clinical nurse research coordinator, Jo Musick at (314) 747-0707.

Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked sixth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.

Alvin J. Siteman Cancer Center is the only NCI-designated Comprehensive Cancer Center within a 240-mile radius of St. Louis. Siteman Cancer Center is composed of the combined cancer research and treatment programs of Barnes-Jewish Hospital and Washington University School of Medicine.

New imaging technique could speed cancer detection

2012-04-03 00:00:00

A new imaging technique relies on light and sound to create detailed, color pictures of tumors deep inside the body. The technology, called photoacoustic tomography, may eventually help doctors diagnose cancer earlier than is now possible and to more precisely monitor the effects of cancer treatment — all without the radiation involved in X-rays and CT scans or the expense of MRIs.

Clinical trials are in the planning stages, but studies in animal models have given researchers a lot to get excited about. That’s because the technology can easily penetrate the body’s tissues to visualize tumors at depths never before possible.

Wang

“This technology is potentially a game changer, both in how we monitor cancer and in how soon we know it’s there,” says biomedical engineer Lihong V. Wang, PhD., who led the team of developers at Washington University in St. Louis.

For example, the technique could reveal the presence of cancer earlier by showing oxygen use by tissues. Excessive oxygen-burning, called hypermetabolism, is a hallmark of the disease. In the early stages, there isn’t much else to go on, so photoacoustic tomography could alert physicians to the presence of the disease at its earliest stage, Wang says.

Wang will explain the technology April 3 at the annual meeting of the American Association for Cancer Research in Chicago. Wang’s presentation follows his publication of a related paper March 23 in Science.

Wang, who is affiliated with the Alvin J. Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine, is working with Washington University physicians to evaluate the technology for four uses: identifying the sentinel lymph nodes for breast cancer staging, which may eliminate the need for surgical lymph node biopsies; monitoring early response to chemotherapy; imaging melanomas; and imaging the gastrointestinal tract.

A major challenge for diagnosing cancer is the inability to see small tumors growing in the body. Physicians have come to accept the grayness of X-ray images and CT scans (which are based on X-rays), where structures appear as lights and shadows. But they are a poor substitute for “photographs” of our insides.

No such photographs exist because light can’t penetrate soft tissue. Tissues scatter light, which limits the ability to see anything beyond the depth of about a millimeter. But scattering doesn’t destroy the light, which can reach a depth of about 7 centimeters, or about 3 inches.

Photoacoustic imagery brings together the best of both worlds — light and sound. It converts light absorbed by soft tissues in the body into sound waves, which easily penetrate tissues. The tissue to be imaged is then irradiated by a nanosecond-pulsed laser at an optical wavelength.

Absorption of light by molecules beneath the surface creates a thermally induced pressure jump that launches sound waves, which are measured by ultrasound receivers at the body’s surface and reassembled to create what is, in effect, a photograph.

Photoacoustic images have a much higher contrast than X-ray images because there are many highly colored molecules in the body that naturally serve as contrast agents. These include hemoglobin, which changes color as it gains or loses oxygen, but also melanin, the pigment that makes moles dark, and DNA, which in its condensed form in the cell nucleus is darker than the cell cytoplasm.

With a little help from organic dyes or genes engineered to express colorful products, photoacoustic tomography can also image tissues, such as lymph nodes, that would otherwise blend in with their surroundings.

“Every issue of every top journal publishes exciting lab discoveries, but only a tiny fraction of them are ever translated into clinical practice,” he says. “My hope is that photoacoustic tomography can help translate microscopic lab discoveries into macroscopic clinical practice.”

Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked sixth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

‘Crazy’ offshoots of Einstein’s theories topic of 2012 McDonnell Distinguished Lecture

2012-04-02 00:00:00

Credit: NASA E/PO, Sonoma State University, Aurore Simonnet

Artist's conception of a black hole pulling gas off a nearby star.

Clifford M. Will, PhD, the James S. McDonnell Professor of Space Sciences in Arts & Sciences, will deliver the McDonnell Distinguished Lecture at 7 p.m. Thursday, April 12, in Room 100, Whitaker Hall, at Washington University in St. Louis.

Will plans to discuss “Black Holes, Waves of Gravity and Other Warped Ideas of Dr. Einstein.” WUSTL’s McDonnell Center for the Space Sciences, which sponsors the lecture series, invites the St. Louis community to attend.

Einstein and his ideas are thoroughly embedded in popular culture, Will says. The wrinkles around Yoda’s eyes were based on Einstein’s, Disney has a line of baby products called Baby Einstein and the cartoon character Dexter of Dexter’s Laboratory apologizes to a photo of Einstein in his locker every time he gets a B on a science test.

Will

One of the most famous movie songs ever (which Will plans to sing) also talks about Einstein.

Although Einstein’s ideas apply mostly to the astronomical domain or the domain of the ultra-small, they do have some practical consequences. GPS systems give accurate coordinates only because Einstein’s theories of general and special relativity are taken into account in their computations.

The clocks in GPS satellites are moving at 14,000 km/hr in orbits that circle the Earth twice per day, much faster than clocks on the surface of the Earth, so Einstein's theory of special relativity applies to them.

But the satellite clocks also experience gravity four times weaker than that on the ground, so Einstein's general relativity theory also comes into play.

The way the time correction works will be revealed at the lecture.

Will plans to devote most of the evening, however, to two of the “crazier” ideas that came out of Einstein’s theories. One is that the interaction of two compact masses, such as orbiting neutron stars, can produce ripples in the curvature of spacetime called gravitational waves. Several gravitational wave detectors have been built, but so far there have been no detection events.

The other is that there are bottomless wells in spacetime from which nothing, not even light, can escape. Because they are invisible by definition, it is also difficult to prove black holes exist, although scientists have begun to build a very strong circumstantial case.

International teams of scientists have embarked on a quest to verify that both gravitational waves and black holes exist, Will says. Building and operating large-scale detectors on the ground, and designing space-based detectors for the future, they hope to detect and measure the waves, and to use those wave signals to reveal the hidden secrets of black holes.

Will’s 1986 book, Was Einstein Right? was reviewed in The New York Times and also made the newspaper’s “Christmas Books” list that year. The book, which focuses on Einstein’s theory of general relativity and the experiments designed to test it, won the highly coveted American Institute of Physics Science Writing Award, which is given annually to the best popular science book.

A second edition was published in 1993, and at last count, it has been translated in 10 languages.

Will’s Theory and Experiment in Gravitational Physics (1981) is considered the bible of the field. It was revised in 1993. His latest book, Gravity: Newtonian, Post-Newtonian, Relativistic, with co-author Eric Poisson, is expected to be completed by late 2012.

A fellow of the American Academy of Arts & Sciences since 2002 and an elected member of the U.S. National Academy of Sciences since 2007, Will has received many honors and awards. In 1986, the American Association of Physics Teachers selected Will as its 46th annual Richtmyer Memorial Lecturer.

In 1989, Will was elected a fellow of the American Physical Society, and in 1996-97, he was named both a J. William Fulbright Fellow and a John Simon Guggenheim Fellow.

Will, who has been referred to as one of the best lecturers in physics, received the 2004 Fellows Award from the Academy of Science of St. Louis for making Einstein’s theory accessible to the public and for making a significant impact on the public understanding of science.

A frequently invited lecturer worldwide, in 2005, Will participated in a 20-city public lecture tour of his native Canada in recognition of the World Year of Physics. He also has given public lectures in French in Paris, Montreal, Quebec City and Sherbrooke.

Will earned a bachelor’s degree in applied mathematics and theoretical physics in 1968 from McMaster University in Hamilton, Ontario, followed three years later by a doctorate in physics from California Institute of Technology.

Will came to WUSTL in 1981 as an associate professor of physics after seven years at Stanford University.

He became a full professor in 1985 and served two terms as department chair (1991-96 and 1997-2002).

Will also will deliver a colloquium, titled “Testing General Relativity in the Strong-Field Regime,” as part of the lecture series, at 4 p.m. Wednesday, April 11, in Room 204, Crow Hall. The colloquium is also free and open to the public.

The McDonnell Center, which was established in 1975 through a gift from the aerospace pioneer James S. McDonnell, is a consortium of WUSTL faculty, research staff and students coming primarily from the departments of Earth and Planetary Sciences and Physics, both in Arts & Sciences, who are working on the cutting edge of space research.

For more information on the talks, contact Trecia Stumbaugh at trecia@wustl.edu or (314) 935-5332.

Ten WUSTL faculty to receive Outstanding St. Louis Scientists Awards

Beth Miller and Diana Lutz — 2012-04-02 00:00:00

The Academy of Science of St. Louis will honor 10 faculty members from Washington University in St. Louis for their contributions and leadership in science and medicine.

The academy will present the Outstanding St. Louis Scientists Awards at its 18th annual dinner Thursday, April 19, at the Chase Park Plaza Hotel.

The awards are designed to focus attention on St. Louis individuals and institutions known around the world for scientific contributions to research, industry and quality of life.

The WUSTL winners:

Michael W. Friedlander, PhD, professor emeritus of physics in Arts & Sciences, will receive the Science Educator Award.

For more than four decades, Friedlander has played a major role in science education both locally and nationally. Each semester since 1994, he has organized a series of four “Saturday Science” public lectures in Department of Physics. The 200-seat lecture hall is often filled.

Beyond the region, Friedlander has been an influence for science understanding with his five books written for the general public. The two published by Harvard University Press describe the history of the study of cosmic rays and what is now known about these energetic particles — an area of astrophysics to which he has contributed significant original research.

Jeffrey I. Gordon, MD, the Robert J. Glazer Distinguished Professor of Pathology and Immunology and founding director of the Center for Genome Sciences and Systems Biology, will receive the Peter H. Raven Lifetime Achievement Award.

Gordon is recognized for his leadership in “establishing the field of human microbiome research.”

His work and this field are providing new understanding of the origins of our biological differences, new approaches for understanding how changes in our cultural traditions and lifestyles are impacting our health and risk for various diseases and new therapeutic approaches to illnesses previously thought to have a microbial component.

A central focus of his lab is the relationship between gut microbial communities and the nutritional status of infants, children and adults living in Westernized and non-Westernized societies.

Scott J. Hultgren, PhD, the Helen Lehbrink Stoever Professor of Molecular Microbiology and director of the Center for Women’s Infectious Disease Research, will receive the Fellows Award.

Hultgren, one of the world’s most accomplished microbiologists, studies urinary tract infections, the most common infectious complaint of women in primary outpatient clinics.

His research has changed scientists’ understanding of the molecular basis of chronic and recurrent urinary tract infections. In addition, he is developing new antibiotics and vaccines to prevent and treat the infections.

Also active in women’s health policy, Hultgren contributed to the strategic plan developed by the Office of Research in Women’s Health to set priorities for research at the National Institutes of Health (NIH). Hultgren was elected into the National Academy of Sciences in 2011.

Timothy J. Ley, MD, the Lewis T. and Rosalind B. Apple Chair in Oncology, professor of medicine and of genetics, and associate director of The Genome Institute; Elaine R. Mardis, PhD, professor of genetics and of molecular microbiology, co-director and director of technology development of The Genome Institute; and Richard K. Wilson, PhD, professor of genetics and director of The Genome Institute, will share the George Engelmann Interdisciplinary/Collaborative Science Award, a new award that recognizes outstanding achievement in science, engineering or technology that results from collaboration among two or more individuals across disciplinary and/or institutional boundaries.

Ley, Mardis and Wilson are recognized for collaborative work that has helped to lay the foundation of cancer genomic research, diagnostics and therapeutics. The academy recognizes them for their unique look at cancer, which has helped to bring in a new era of personalized medicine.

The academy also commended them for their participation in a $65 million partnership with St. Jude Children’s Hospital to define the gene mutation spectrum in pediatric cancer. That work is creating a public database that will be shared with the international scientific community to speed progress toward fighting childhood cancers.

Audrey R. Odom, MD, PhD, assistant professor of pediatrics and of molecular microbiology, will receive the Innovation Award.

Odom is dissecting a key metabolic pathway in malaria that is not found in humans and provides a novel target for drug development.

Worldwide, there is an urgent need for new drugs to treat malaria, which causes more than a million deaths per year, mostly in young children. Odom’s lab focuses on improving the fundamental understanding of the basic molecular and cellular biology of the malaria parasite to identify new antimalarial drug targets.

Mabel L. Purkerson, MD, professor emerita of medicine, will receive the Trustee Award.

For more than 40 years, Purkerson served as a clinician, teacher, investigator and administrator at the School of Medicine. The academy recognizes her as a physician/scientist, leading by example, focusing on excellence and being open to new opportunities and techniques.

She used an interdisciplinary approach to find new strategies and tools to further her research, allowing her to make substantial contributions in the field of kidney physiology. These achievements led to her becoming the first female full professor in the Department of Medicine.

Larry J. Shapiro, MD, executive vice chancellor for medical affairs and dean of the School of Medicine, will receive the academy’s individual Science Leadership Award.

The academy recognizes Shapiro for his accomplishments in transforming the medical school’s research enterprise to focus on clinical and translational research, interdisciplinary teams, visionary genomics and regional partnerships. The academy commended him for implementing BioMed 21, the university’s initiative to facilitate multidisciplinary, collaborative research and rapidly apply breakthroughs to patient care.

Stuart A. Solin, PhD, the Charles M. Hohenberg Professor of Experimental Physics, will receive the James B. Eads Award.

Solin is recognized for significant discoveries and initiatives in the fields of condensed matter physics and nanosciences. Most recently, as inventor of the EMR (Extraordinary MagnetoResistance) sensor device concept, he has seeded a hugely important area of research, which has now been taken up extensively by industry around the globe.

His work has the capacity to revolutionize data storage and retrieval in computers. Stuart has already started work on the biological and medical application of his new class of sensors. Indications are that EMR and EEC (Extraordinary Electroconductance) nanoscale sensors can be used for cancer detection.

New imaging technique moves from lab to clinic

Diana Lutz — 2012-03-22 00:00:00

Every new imaging technology has an aura of magic about it because it suddenly reveals what had been concealed, and makes visible what had been invisible. So, too, with photoacoustic tomography, which is allowing scientists to virtually peel away the top several inches of flesh to see what lies beneath.

song hu/lihong wang

The arteries (red) and veins (green) stand out clearly in a photoacoustic microscope image of a mouse ear. The technique is very sensitive to color changes like those that occur as hemoglobin becomes saturated with oxygen (sO₂).

The technique achieves this depth vision by an elegant marriage between light and sound, combining the high contrast due to light absorption by colored molecules such as hemoglobin or melanin with the spatial resolution of ultrasound.

Lihong V. Wang, PhD, the Gene K. Beare Distinguished Professor of Biomedical Engineering in the School of Engineering & Applied Science at Washington University in St. Louis, summarizes the state of the art in photoacoustic imaging in the March 23 issue of Science.

Chris favazza/ Lihong Wang

This image of the hemoglobin in the human palm is slightly less sharp than the image of the mouse ear because the blood vessels lie deeper. As a rule of thumb, the spatial resolution of a photoacoustic image is about 1/200th of the imaging depth. The technique is capable of reaching as deeply as 7 centimeters (nearly three inches).

He is already working with physicians at the Washington University School of Medicine to move four applications of photoacoustic tomography into clinical trials. One is to visualize the sentinel lymph nodes that are important in breast cancer staging; a second to monitor early response to chemotherapy; a third to image melanomas; and the fourth to image the gastrointestinal tract.

Among the most exciting advances is the ability of photoacoustic tomography to reveal the use of oxygen by tissues, because excessive oxygen-burning (called hypermetabolism) is a hallmark of cancer.

Joon Mo Yang/lihong wang

Since most animals have body plans that are essentially a tube within a tube, a surprising amount of the body is within the reach of photoacoustic tomography. This image shows a rabbit’s esophagus and adjacent internal organs. Photoacoustic colonoscopy would allow physicians to visualize not just superficial polyps but also deeper lesions

In the early stages of cancer, there isn’t much else to go on, Wang says, and so an early warning diagnostic test that does not require a contrast agent is potentially a game changer.

How photoacoustic tomography works

Although we’ve all come to accept the grayness of X-ray images, where structure appears as lights and shadows, they are a poor substitute for “photographs” of our insides.

No such photographs exist because light photons can penetrate soft tissue only to the depth of about a millimeter before they’re so scattered it isn’t possible to unsnarl their paths and create an image. But scattering doesn’t destroy the photons, which can reach a depth of about 7 centimeters (about 3 inches).

The trick of photoacoustic tomography is to convert light absorbed at depth to sound waves, which scatter a thousand times less than light, for transmission back to the surface. The tissue to be imaged is irradiated by a nanosecond-pulsed laser at an optical wavelength.

Absorption by light by molecules beneath the surface creates a thermally induced pressure jump that launches sound waves that are measured by ultrasound receivers at the surface and reassembled to create what is, in effect, a photograph.

http://youtu.be/DPS1x32DKdw

Light, unlike X-rays, which also penetrate deeply, poses no health hazard. Moreover, photoacoustic images have much higher contrast than X-ray images because there are many highly colored molecules in the body that serve as “endogenous” contrast agents. These include hemoglobin, which changes color as it gains or loses oxygen, but also melanin, the pigment that makes moles dark, and DNA, which in its “condensed” form in the cell nucleus is “darker” than the cell cytoplasm.

With a little help from “exogenous” (introduced) contrast agents, such as organic dyes or genes engineered to express colorful products, photoacoustic tomography can also image tissues, such as lymph nodes, that otherwise blend in with their surroundings. Wang also has been experimenting with “reporter genes,” genes that encode a colored product, which shows up well in photoacoustic images.

Putting down the scalpel

Todd Erpelding, alejandro Garcia-Uribe, Zhilin Hu, Rameez Chatni, Catherine Appleton, Julie Margenthaler, and Ladislav Jankovic

Because lymph is clear or pale yellow, it is harder to visualize than blood. This photoacoustic tomography image of a sentinel lymph node (SLN) in woman with breast cancer was made by injecting the breast with methylene blue dye, which acts to increase the contrast between the node and its surroundings. The lymph node can then be biopsied by needle rather than by surgery. In collaboration with Philips Resarch this technique for sentinel node biopsy is now in clinical trials at Barnes-Jewish Hospital in St. Louis, the hospital affiliated with Washington University in St. Louis.

Sentinel node biopsy provides a good example of the improvement photoacoustic imaging promises over current imaging practice. Sentinel nodes are the nodes nearest a tumor, such as a breast tumor, to which cancerous cells would first migrate.

In a sentinel node biopsy, a surgeon injects a radioactive substance, a dye, or both near a tumor. The body treats both substances as foreign, so they flow to the first draining node to be filtered and flushed from the body.

“A gamma probe or a Geiger counter is used to locate the radioactive particles,” Wang says, “but it gives only a rough idea of the node’s location.” To find the node, the surgeon must cut open the area and follow the dye visually to the sentinel lymph node.

Roughly 10 percent of the patients who undergo this procedure are found to have cancerous nodes, but 5 percent of the patients suffer a side effect, such as numbness, swelling (lymphedema) or a decreased range of motion. So the diagnostic procedure itself is not without risk.

Wang proposes instead simply to inject an optical dye that shows up so clearly in photoacoustic images that a hollow needle can be guided directly to the sentinel lymph node and a sample of tissue taken through the needle.

In the clinical trial now under way, he says, the surgeon is not taking tissue but instead deploying a tiny metal clip through the needle. The patient then undergoes lymph node dissection, the “standard of care” treatment. The dissected lymph node is X-rayed to see whether it contains the clip.

“If this technique proves accurate, we will be converting a surgical procedure into a needle biopsy possible on an outpatient basis,” Wang says. “In the U.S. alone, 100,000 of these surgical biopsies are done very year, so the new procedure would spare many patients injury — not to mention expense.”

Seeing function

One exciting aspect of photoacoustic tomography is that images contain functional as well as structural information because color reflects the chemical composition and chemistry determines function.

Photoacoustic tomography, for example, can detect the oxygen saturation of hemoglobin, which is bright red when it is carrying oxygen and turns darker red when it releases it.

Almost all diseases, especially cancer and diabetes, cause abnormal oxygen metabolism. So the metabolic rate of oxygen use is an important hallmark of disease.

JUNJIE Yao/Lihong Wang

One of the most exciting uses of photoacoustic tomography is to measure oxygen metabolism, a marker for cancer that may permit much earlier diagnosis than is now possible. In this example, melanoma tumor cells were injected into a mouse ear on day 1. By day 7, there were noticeable changes in the blood flow rate (top graph, right), and the metabolic rate of oxygen usage (bottom graph, right). Counterintuitively, the tumor did not increase the oxygen extraction fraction (middle graph). MT stands for melanoma tumor and VD for vasodilation. The colors correspond to depth, with blue being superficial and red deep.

Together with other parameters that can be measured in the photoacoustic images, such as vessel cross-section, concentration of hemoglobin and blood flow speed, the gradient of oxygen saturation can be used to calculate the oxygen use by a region of tissue.

The imaging technique most widely used to measure oxygen use is positron emission tomography (PET), which requires the injection or inhalation of a radioactively labeled tracer and undesirable radiation exposure.

A: Chi zhang/konstantin Maslov/Lihong wang

B: Song Hu/konstantin maslov/lihong wang

C:Chris Favazza/lynn Cornelius/lihong wang

D: todd erpelding/alejandro garcia-urbe/zhilinHu/Catherine Appleton/Julie Margenthaler/Ladislav Jankovic

Among imaging techniques photoacoustic imaging is uniquely able to maintain clarity over a wide range of scales. Shown here are images of tiny organelles containing the pigment melanin in the ear of a black mouse; individual red blood cells (RBC) traveling along a capillary in a mouse ear; a nevus (mole) on a human arm; and a tumor in a woman undergoing sentinel node biopsy. As the scale bars show, the size of the structures in the images varies by a factor of a thousand.

Last year in the Journal of Biomedical Optics, Wang’s team demonstrated that oxygen metabolism betrayed the presence of a melanoma (a skin cancer) and of a glioblastoma (a brain tumor) within a few days of the injection of tumor cells in an animal model. Oxygen use doubled in a week.

“Because hypermetabolism is a quintessential hallmark of cancer,” Wang says, “photoacoustic imaging may allow cancer to be detected at the earliest stage without using a foreign contrast agent.”

Wang will be speaking about photoacoustic tomography at the annual meeting of the American Association for Cancer Research (AACR) this spring.

A singular vision

Wang, who has worked on photoacoustic imaging for more than 10 years, sees a subtler but ultimately even more transformative advantage to the technology.

“Every issue of every top journal publishes exciting lab discoveries,” he says, “but only a tiny fraction of them are ever translated into clinical practice.” Part of the problem is that images are made by different methods at different scales, making comparisons across scales difficult.

“In current practice,” he says, “we use optical microscopy to examine organelles and cells and nonoptical imaging techniques such as X-ray tomography for tissues and organs. None of the clinical imaging technologies give you the strong contrast of the optical techniques.

“So between the micro domain and the macro domain there’s a huge divide, because people can’t relate the images acquired at one length scale to those acquired at another.

“My hope is that photoacoustic tomography, which has consistent contrast over all length scales, can help translate the microscopic lab discoveries to macroscopic clinical practice.”

For similar reasons, he thinks photoacoustic imaging will be useful for systems biology, the new movement in bioscience to focus on systems as a whole rather than on individual components.

“We’re really just tool builders,” Wang says, “who are going to help other scientists make the revolutionary discoveries in biology and medicine. At least that’s my hope.”

Seismic survey at the Mariana trench will follow water dragged down into the Earth’s mantle

Diana Lutz — 2012-03-22 00:00:00

Doug Wiens

The Thomas G. Thompson and the Marcus G. Langseth at the Navy Pier in Guam. The Thompson laid seismic instruments, which are stacked and ready on its deck, and the Langseth then sailed transects over the instrumented area, firing its airgun array and recording the reflections from subsurface rock layers.

Last month, Doug Wiens, PhD, professor of earth and planetary science at Washington University in St. Louis, and two WUSTL students were cruising the tropical waters of the western Pacific above the Mariana trench aboard the research vessel Thomas G. Thompson.

The trench is a subduction zone, where the ancient, cold and dense Pacific plate slides beneath the younger, lighter high-riding Mariana Plate, the leading edge of the Pacific Plate sinking deep into the Earth’s mantle as the plates slowly converge.

Taking turns with his shipmates, Wiens swung bright-yellow ocean bottom seismometers and hydrophones off the fantail, and lowered them gently to the water’s surface, as the ship laid out a matrix of instruments for a seismic survey on the trench.

The survey, which Wiens leads together with Daniel Lizarralde, PhD, of the Woods Hole Oceanographic Institution, will follow the water chemically bound to the down-diving Pacific Plate or trapped in deep faults that open in the plate as it bends. The work is funded by the National Science Foundation.

Scientists have only recently begun to study the subsurface water cycle, which promises to be as important as the more familiar surface water cycle to the character of the planet.

Hydration reactions along the subducting plate are thought to carry water deep into the Earth, and dehydration reactions at greater depths release fluids into the overlying mantle that promote melting and volcanism.

The water also plays a role in the strong earthquakes characteristic of subduction zones. Hydrated rock and water under high pressure are thought to lubricate the boundary between the plates and to permit sudden slippage.

http://youtu.be/2Pnq2OK9Svw

Dropping the instruments

Between Jan. 26 and Feb. 9, working day and night, watch-on and watch-off, the Thompson laid down 80 ocean bottom seismometers and five hydrophones.

The hydrophones, which detect pressure waves and convert them into electrical signals, provide less information than the seismometers, which register ground motion, but they can be tethered four miles deep in the water column where the bottom is so far down seismometers would implode as they sank.

The Thompson sailed over some of the most famous real estate in the world, the Mariana trench, which includes the bathtub-shaped depression called the Challenger Deep, to which Avatar director James Cameron plans to plunge in a purpose-built one-man submersible called the Deep Challenger.

Seven miles down, the pressure in the Deep is 1,000 atmospheres (1,000 times the pressure at sea level on dry land) or roughly 8 tons per square inch. Seismometers, says Wiens, only go down four miles.

The trench is created by the subduction of some of the world’s oldest oceanic crust, which plunges underneath the Mariana Isalnds so steeply at places that it is going almost straight down.

The active survey

After the Thompson returned to Guam and Wiens flew back to St. Louis to resume his less romantic duties as chair of the Department of Earth and Planetary Sciences, the research vessel Marcus G. Langseth began to sail transects above the matrix of seismometers, firing the 36-airgun array on its back deck.

Heather Relyea

Patrick Shore, a WUSTL research scientist, and two students set off on a rented fishing boat called the Kaiyu III. Sailing more than 600 miles over the open ocean they placed seismometers on five of the islands in the Mariana chain to supplement those on the ocean bottom.

The sound blasts reflected from the boundaries between rock layers a few miles beneath the ocean floor were picked up by an five-mile-long “streamer,” or hose containing many hydrophones, towed just beneath the surface behind the ship.

This was the “active” stage of a seismic survey with a “passive” stage yet to come.

After the seismic survey, the Langseth returned to pick up 60 seismometers, leaving behind 20 broadband seismometers and the hydrophones that will listen for a year to the reverberations from distant earthquakes, allowing the seismologists to map structures as deep as 60 miles beneath the surface.

In the meantime Patrick Shore, a research scientist in earth and planetary science, and two Washington University students had set sail across the ocean in a tiny vessel, the Kaiyu III, to install seismometers on the Mariana islands that will also supply data for the “passive” stage of the survey.

Water, water everywhere

Wikimedia Commons

When water is carried into the mantle, the mantle rock undergoes a low-temperature metamorphic process in which it is oxidized and hydrolyzed to form serpentinite, a rock named for its scaly surface.

Water plays a completely different role at depth than it does on the surface of the Earth. Water infiltrating the mantle through faults hydrates the mantle rock on either side of the fault.

In a low temperature process called serpentinization, it transforms mantle rock such as the green periodotite into serpentinite, a rock with a dark scaly surface like a serpent’s skin.

As the slab plunges yet deeper, dehydration reactions release water, which at such great pressure and temperature exists as a supercritical fluid that can drift through materials like a gas and dissolve them like a fluid. The fluid rises into the overlying mantle where it lowers the melting point of rock and triggers the violent eruptions of magma that created the Mariana Islands, to which Shore was sailing.

“We think that much of the water that goes down at the Mariana trench actually comes back out of the earth into the atmosphere as water vapor when the volcanos erupt hundreds of miles away,” Wiens says.

The scientists will map the distribution of serpentinite in the subducting plate and overlying mantle, by looking for regions where certain seismicwaves travel more slowly than usual.

Heather Relyea

The volcano on Pagan, one of the islands visited by the Kaiyu III, has erupted several times over the last 30 years. Fortunately it was only moderately active when the WUSTL team was there, expelling steam here reflecting the light of the setting sun.

Tracing the water cycle within subduction zones will allow the scientists to better understand island-arc volcanism and subduction-zone earthquakes, which are among the most powerful in the world

But the role of subsurface water is not limited to these zones. Scientists don’t know how subduction got started in the first place, but water may be a necessary ingredient. Venus, which is in many ways similar to Earth, has volcanism but no plate tectonics, probably because it is bone dry.

Agrawal wins NSF CAREER award

2012-03-16 00:00:00

Agrawal

Kunal Agrawal, PhD, assistant professor of computer science & engineering in the School of Engineering & Applied Science at Washington University in St. Louis, has won a prestigious Faculty Early Career Development Award (CAREER award) from the National Science Foundation (NSF).

The awards are given “in support of the early career-development activities of those teacher-scholars who most effectively integrate research and education within the context of the mission of their organization” with the goal of “building a firm foundation for a lifetime of integrated contributions to research and education.”

According to Ralph S. Quatrano, PhD, dean of the School of Engineering & Applied Science, 12 engineering faculty have received a CAREER award since 2005, including nine of the 20 faculty in the Department of Computer Science & Engineering.

“This truly remarkable achievement is a significant recognition of the tremendous quality of our faculty,” Quatrano says.

The goal of Agrawal’s project, titled “Provably Good Concurrency Platforms for Streaming Applications,” is to design platforms that will allow programmers to easily write correct and efficient high-throughput parallel programs.

In particular, her platforms will be useful for data-intensive applications, such as audio, video and signal processing, allowing these applications to run on modern multicore machines.

Most computers made in the past decade are multicores; that is, they contain multiple processing elements, or cores. In addition, the number of cores on machines is increasing at close to an exponential rate.

Traditional sequential programs cannot make use of more than one core at a time, potentially wasting resources. In order to execute efficiently on these machines, programmers must write parallel programs, programs capable of using more than one core at the same time.

Agrawal’s project concentrates on designing platforms that can efficiently execute a class of parallel programs called streaming programs. In streaming applications, a set (potentially ordered) of operations is applied to each element in a data set (the stream).

Agrawal

One player’s view of a sample puzzle game. The cooperative multiplayer game teaches collaboration with minimal information exchange. The goal is to design a protocol followed by all players that allows them all to get to the yellow ball without colliding with other players' balls, which they cannot see.

Agrawal’s work will enable automatic management of synchronization and scheduling of operations, so that the programmers can write their programs at a high level without worrying about those details. A large class of data intensive applications, including bioinformatics applications, and many scientific applications, as well as audio, visual and image processing, can be expressed as streaming programs.

“This research will advance the state-of-the-art in streaming platforms, both theoretically and practically,” Agrawal says. “While the research is theoretical, we want to design platforms that both academic and industry partners will want to implement in their streaming systems.”

The research will support both graduate and undergraduate research as well as Agrawal’s.

In addition, the research will be integrated into Agrawal’s graduate course “Theory of Parallel Systems.” Agrawal also plans to incorporate parallal algorithms in the undergraduate algorithms and data structures course she teaches. Finally, in her free time, Agrawal designs puzzles that indirectly teach students about parallel computing concepts.

Agrawal joined WUSTL after earning a PhD in computer science from the Massachusetts Institute of Technology. She earned a master’s degree in computer science from the National University of Singapore and a bachelor’s degree from Mumbai University.

McCarthy installed as new Spencer T. Olin professor

2012-03-15 00:00:00

Mary Butkus/WUSTL

Chancellor Mark S. Wrighton presents mathematician John E. McCarthy with the medallion that symbolizes his installation as the Spencer T. Olin Professor in Arts & Sciences.

Mathematician John E. McCarthy, PhD, was installed March 2 as the Spencer T. Olin Professor in Arts & Sciences in a ceremony in Holmes Lounge.

“An endowed professorship at Washington University is the highest level appointment that we can make, and Professor McCarthy joins a very distinguished group of fellow chair holders who have made a big difference in the life of this community,” Chancellor Mark S. Wrighton said.

The professorship was established in 1996 with a bequest from Spencer T. Olin, a longtime member of the WUSTL Board of Trustees. The first holder of the professorship was Douglass C. North, PhD, a 1993 Nobel Laureate in economics.

The installation was attended by Mary Dell Pritzlaff, daughter of Spencer T. Olin and Ann W. Olin and university trustee emerita, who has, Wrighton said, “continued the great legacy of this family as a wise counselor and generous contributor to our success.”

Wrighton presented Prizlaff as well as McCarthy with a university medallion to celebrate the occasion of McCarthy’s installation to the Olin professorship.

Gary S. Wihl, PhD, the Hortense and Tobias Lewin Distinguished Professor in the Humanities and Dean of the Faculty of Arts & Sciences, introduced McCarthy and spoke about his scholarly contributions.

“John is the son of two Limerick physicians, and perhaps a career in medicine seemed the most likely prospect,” Wihl said, “but in his freshman year at Dublin University he discovered a love of pure mathematics and never looked back.”

McCarthy went on to earn a PhD in mathematics at the University of California, Berkeley.

Wihl highlighted McCarthy’s work with Jim Agler, PhD, on an the extension of a famous theorem in mathematics, called the Pick interpolation theorem, that concerns the minimum energy curve that fits a set of data points.

“Their work is a multi-dimensional generalization of this classical one-dimensional result formulated by Georg Pick, PhD, in 1916, and their book on the subject has become an indispensible reference work in the field of mathematics,” Wihl said.

Mary Butkus/WUSTL

McCarthy receives congratulations from his daughter, Fiona, after the ceremony.

Wihl also noted that 15 of 60 papers McCarthy has published concern applied rather than theoretical topics, addressing problems in ultrasonic imaging, control theory, cancer therapy and plasma physics, among other topics.

McCarthy has received more than $3 million in funding, an unusually high level of support for a pure mathematician, and has been continuously supported by the National Science Foundation since he received his PhD in 1989.

Wihl said McCarthy is also one of the department’s most popular teachers, and mentioned that he has published a book, Transitions to Higher Mathematics, addressed to prospective math majors.

Following the formal installation and the presentation of the professorship medallion, McCarthy spoke on “Why Pure Mathematics Matters.”

“One of the very strange thing about mathematics,” McCarthy said, “is that pure mathematics that is pursued purely for aesthetic reasons, to explore the beauty of the ideas, is unreasonably effective. Ideas that crop up in pure mathematics turn out decades, sometimes even centuries, later to be just the right tool to solve a problem in applied science.”

Among the examples he gave were the investigations of non-Euclidean geometry in the 19th century, without which the theory of relativity couldn’t have been formulated; and the study of infinite dimensional systems, which was necessary for formulating quantum mechanics.

Work he himself had done on quadrature domains, two-dimensional shapes that have a very smooth boundary and are not allowed to have any corners, turned out to predict the equilibrium shapes of charged plasmas within the “traps” that contain them.

“Once you make this connection,” he said, “it tells you what charge to put on the wall to keep the plasma in equilibrium and how to get any shape you want — except ones with corners.”

About Ann W. and Spencer T. Olin

Spencer Olin graduated in 1921 from Cornell University and began his career working in the family business, Western Cartridge Company in East Alton, Ill. He was vice president of Olin Corp., when its Winchester Repeating Arms subsidiary turned out 15 billion rounds of ammunition for the Allies during World War II.

He raised millions of dollars for the 1952 presidential campaign of Dwight D. Eisenhower and was the national finance chairman for the Republican party from 1950-1960 and treasurer of the Republican National Committee from 1960-62.

Olin was granted an honorary doctorate from WUSTL in 1969. His wife, Ann Whitney Olin, was heavily involved in educational philanthropy, and the Ann Whitney Olin Women’s Building is named for her.

Also named for the Olins are endowed professorships in biology, engineering and medicine.

Spencer and Ann Olin also directed their generosity toward the Mr. and Mrs. Spencer T. Olin Fellowship program for Women in Graduate Study, the Olin conference in women in higher education and the professions, and the Olin residence hall at the School of Medicine.

Ann Olin died in 1976; Spencer Olin in 1995.

Finding solutions to Achilles’ heel of renewable energy: intermittency

Diana Lutz — 2012-03-15 00:00:00

William F. Pickard introduces the February 2012 special issue of the Proceedings of the IEEE by quoting the Bible: “The wind bloweth where it listeth.” That, in so many words, describes the major technological issue with renewable sources of energy, such as solar and wind power.

“Wind turbines or solar collectors alone cannot supply baseload power,” Pickard says. “It’s blowing beautifully outside today, and if you had a wind turbine you’d be in fat city. But at sundown the wind could suddenly drop and there’d be no sunshine to replace it. You would freeze in the dark — unless you had stored up energy.”

Intermittency, sometimes called the Achilles’ heel of renewable energy, has so far limited the penetration of renewable sources in most power grids.

Pickard, PhD, senior professor of electrical and systems engineering in the School of Engineering & Applied Science at Washington University in St. Louis and a life fellow of the IEEE, co-edited the special issue, “The Intermittency Challenge: Massive Energy Storage in a Sustainable Future,” with Derek Abbott, PhD, professor in the School of Electrical and Electronic Engineering at the University of Adelaide and a fellow of the IEEE.

“Most projections show that late in the 21st century, fossil-fuel shortages are going to bite hard,” Pickard says. “If you’re an optimist, you might say 75 years, and we’re going to be in trouble — real trouble. And once economical sources of fossil fuels approach depletion, we have no certain recourse except to renewables.”

What, then, can be done about the problem of intermittency? The Proceedings of the IEEE, the most highly cited general interest journal in electrical engineering and computer science, delves into the problem, focusing on schemes for rendering renewable energy reliable and dispatchable, particularly massive storage facilities for energy.

Pickard, who is retired from teaching, is motivated not by his own welfare but by his grandson’s. “In 70 years,” he says, “you and I will be dead, but my grandson might be left sitting with no energy resources. What benefit has he received from this dissipation of fossil fuels? I got a benefit, you got a benefit, but he gets the ashes.”

Transnational power grids
One of the more ambitious articles in the issue describes a giant power grid, to be called the Pan-Asian Energy Infrastructure, that would encompass China, Japan, South Korean, the 10 Association of Southeast Asian Nation (ASEAN) states and Australia.

Wind energy is abundant in China and Mongolia, and solar energy is abundant in Australia’s interior. Together, the authors say, they “represent Asia’s most plentiful renewable energy resources for which capture technology currently exists.”

With a grid this big, the authors say, averaging effects come into play and uncorrelated intermittencies can partially cancel each other out.

“Northern China’s peak electricity demand occurs in winter because of heating needs. Australia’s Outback solar energy resources are strongest in the southern summer, which is the northern winter. Therefore, Australia’s peak solar energy output is suited to meeting China’s winter heating peaks.”

This is not the only transnational grid either planned or under construction.

A group of European companies and the Desertec Foundation envision that, by 2050, solar power plants in the Middle East and North Africa will satisfy 70 percent of the area’s electricity needs and 17 percent of the electricity needs of the European Union and some neighboring countries.

The solar energy would be transmitted across North Africa and connected to Europe across the Mediterranean Sea. Construction of the Desertec’s first 500-megawatt solar farm in Morocco is scheduled to start in 2012.

Ultrahigh-voltage DC power transmission
But, says Pickard, you can’t ship power over extremely long distances through interconnected synchronous AC systems, because of stability problems. “What you get is sloshing inside the network area and sloshing will begin to take the network down.”

For long-distance transfer of bulk power ultrahigh-voltage (800 kilovolt) DC lines are needed, he says. These lines allow higher transmitted power with the same stability margins and lower losses.

The technical problems with these lines are not trivial, Pickard says, but they’re already being solved — in China. According to the authors of an article in the Proceedings volume on ultrahigh-voltage transmission, “China is constructing a number of high-power DC energy highways, superimposed on the AC grid, in order to transmit electric power from huge hydropower plants in the center of the country to load centers located as far as 2,000 to 3,000 kilometers away.”

Massive energy storage
Most schemes for the energy future, including transnational grids, also will require massive energy storage, some scheme to transform surplus grid energy into a different but conveniently stored form and then back-converted and returned to the grid when electric power is needed. Pickard calls them “granaries for electricity.”

By massive, Pickard means storage with a rated output power of at least 1 gigawatt and a rated storage capacity of at least 2 gigawattdays, enough to see a major metropolitan area through most emergencies.

Many of these storage schemes assume the baseload power would be supplied by concentrating solar power (CSP) systems. A CSP system uses mirrors to bring solar radiation to a hot focus that can then be used to superheat steam and run a turbine for power generation.

Surplus energy from the concentrators could be stored either chemically or thermally. Chemical systems might be based on the reversible dissociation of ammonia or on dissociated metal hydrides. Thermal ones might store the heat directly in concrete or in molten salt.

Compressed air and pumped hydro
But, says Pickard, if you look at the website of the Electricity Storage Association, only two energy storage technologies stand out as truly massive. They are compressed air energy storage and pumped hydro.

Compressed air energy storage is really quite simple, he says. “When you have energy you don’t know what to do with, you simply compress air into a cavity under the Earth and when you need the electricity, you blow this air through a high-speed turbine, spinning a generator, and you’ve got your energy again.”

Of course, there is a catch. As anyone who has pumped up a bike tire knows, when you compress air, it heats up and when you allow it to expand, it cools down. To avoid thermally cycling your storage chamber, he says, you would need to compress the air in stages, with counterflow heat exchangers between the stages.

“If you believe the design figures, you can get 60 or 75 percent turnaround efficiency, which isn’t bad. The only problem is that nobody has ever built a functioning adiabatic compressed-air energy-storage system,” Pickard says.

Pickard prefers pumped hydro, but with a twist. To achieve the goal of 2 gigawattdays of stored power, you’d need a reservoir that would have roughly the volume of 10 Great Pyramids, and to minimize losses and maximize power, this reservoir would have to be several hundred meters above a lower reservoir and yet close to it horizontally.

“The solution is to excavate an underground reservoir many hundreds of meters below surface level and to exchange water between it and a surface reservoir created immediately above it and diked using spoil from the excavation. This variation of hydro storage is called underground pumped hydro,” Pickard says.

Such a facility could be put almost anywhere that there was low-quality land underlain with competent rock — in industrial brownfields, for example.

But, says Pickard, “if underground pumped hydro is so great, how come it does not yet exist?” Perhaps because to displace an entrenched technology, the new technology must be clearly superior under present conditions, he says. But the superiority of pumped hydro may become “starkly manifest” only in the future.

Pickard says it is important to remember that there are moral as well as economic and technical dimensions to the intermittency challenge. If our generation lets the matter slide, “our descendants will be saddled with the detritus of a wastrel lifestyle.”

The entire issue is available free to the WUSTL community here.

Other readers must either benefit from institutional subscriptions or purchase the issue.

WUSTL anthropologists’ work prompts Republic of Congo to enlarge national park

Jessica Daues — 2012-03-02 00:00:00

Ian Nichols/National Geographic Society

Many of the Goualougo Triangle chimpanzees are “naïve,” meaning they’ve had little exposure to humans.

Research by Washington University in St. Louis anthropologist Crickette Sanz, PhD, and colleague David Morgan, PhD, has spurred the Republic of Congo to enlarge its Nouabalé-Ndoki National Park boundaries to include the Goualougo Triangle.

The Goualougo Triangle is a remote, pristine forest that is home to at least 14 communities of “naïve” chimpanzees with little exposure to humans.

The expansion, announced in January, increases the size of the protected area by 144 square miles to encompass 1,636 square miles of the northern Republic of Congo. The park is managed by the Republic of Congo’s Ministere du Developpement Durable, de l'Economie Forestiere et de l’Environnement with support from the Wildlife Conservation Society (WCS).

Sanz

“This expansion is a great victory for scientists and conservationists because the Goualougo area and its animal populations are unique throughout the globe, and it holds great promise for further research in many different fields, including anthropology,” Sanz says.

The Goualougo Triangle, a dense lowland forest, is home to approximately 600 chimpanzees, including the chimpanzee communities studied by Sanz, assistant professor of anthropology in Arts & Sciences at WUSTL, and her husband, Morgan, research associate in anthropology at WUSTL and conservation fellow at the Lincoln Park Zoo in Chicago.

Many of the Goualougo Triangle chimpanzees are “naïve,” meaning they’ve had little exposure to humans and will investigate humans they see, rather than run from them.

Studies by Sanz and Morgan have shown that this population of chimpanzees uses a number of specialized tool sets to extract insects from nests.

Ian Nichols/National Geographic Society

Studies by WUSTL anthropologist Crickette Sanz, PhD, helped influence the Republic of Congo to preserve the Goualougo Triangle.

For example, a stout wooden tool is used to make an entry point into a termite nest, and then a flexible probe is used to extract the termite snacks. Their discoveries were the first to show the customary use of complex and improved tool designs by wild apes.

This and other discoveries by Sanz and Morgan directly influenced the government of the Republic of Congo to increase the size of the national park to include the Goualougo Triangle and its populations of chimpanzees, gorillas, elephants, leopards and more.

“The exquisite research of Crickette Sanz and David Morgan on the chimpanzees of the Goualougo Triangle has opened a window into the cultural lives of these extraordinary beings and shown us how our own species’ actions, such as logging, are impacting those lives,” says James Deutsch, WCS director for Africa Programs.

“In doing so, they have caught the imagination of local people, the government of Congo and the whole world, helping to ensure that the Goualougo and its inhabitants will be forever secure,” Deutsch says.

Before becoming part of the park, the Goualougo Triangle was under threat of logging, poaching and encroachment by human populations. By protecting such a large area, the Republic of Congo is giving Sanz, Morgan and the dedicated team of Congolese researchers that they work with a unique opportunity to study chimpanzee communities in a large, intact environment.

“This is the best setting to document the maintenance of complex tool technology by wild chimpanzees and also understand what other aspects of their society differ from other ape populations,” Sanz says.

Ian Nichols/National Geographic Society

Leopards, elephants, gorillas and many other animals also call the Goualougo Triangle home.

“Undoubtedly the Goualougo apes hold further insights for our understanding of the behavior of our closest living relatives and also that of our hominoid ancestors.”

Sanz and Morgan also study another major threat (besides poaching and habitat destruction) to wild apes: disease.

Their research in the Goualougo Triangle has helped to identify the risk factors of disease infection to local human and ape populations, including Ebola Hemorrhagic Fever and Strongyloides stercoralis, or threadworm.

Research from the area has helped scientists learn more about other diseases as well: identification of Plasmodium DNA sequences in fecal samples collected from Goualougo gorillas helped researchers pinpoint the origins of a deadly strain of malaria.

Michael Nichols/National Geographic Society

Sanz hopes what researchers learn about Goualougo Triangle chimpanzees can help chimps in other areas.

Sanz says she hopes that the ongoing research in the Goualougo Triangle will further advance humans’ understanding of ape behavioral ecology while also helping to improve the survival prospects of apes in regions still under threat.

“Working with the Wildlife Conservation Society, we’re forging new collaborations with the government of Congo and the local logging companies to document the complexities of forest and wildlife ecology in secondary habitats and across large landscapes,” Sanz says. “This will enable us to identify other ape strongholds and also develop policies to mitigate the negative impacts of logging on apes.”

Scientists learn how insects ‘remodel’ their bodies between life stages

Diana Lutz — 2012-02-28 00:00:00

Ian and Dianne Duncan

Key to fruit fly metamorphosis are genes whose expression is induced by pulses of a steroid hormone. In this adult male fly, one of these steroid-sensitive genes, E93, is expressed in every tissue (clockwise from top): mouth parts, eye, thorax, abdomen, leg, wing and antenna.

It’s one of life’s special moments: a child finds a fat caterpillar, puts it in a jar with a twig and a few leaves, and awakens one day to find the caterpillar has disappeared and an elegant but apparently lifeless case now hangs from the twig.

Then, when the jar has been forgotten, soft beating against its glass walls calls attention to a new wonder: the jar now holds a fragile-winged butterfly or dusky moth with fringed antennae.

These transformations are so startling that a child’s awe seems a more appropriate response than an adult’s calm acceptance.

How is it, after all, that an insect can remake itself so completely that it appears to be a different creature altogether, not just once, but several times in its lifetime?

Working with fruit flies rather than butterflies, a team led by Ian and Dianne Duncan of Washington University in St. Louis provides part of the answer in the latest issue of PNAS. Ian Duncan, PhD, is professor of biology in Arts & Sciences; Dianne Duncan is a research associate and director of the Biology Imaging Facility.

The puzzling question

Fruit flies go through three main life phases: the larva, the pupa, and the adult.

FlyBase

Fruit flies go through a whole series of transitions between life stages, as shown here. The larval molts are called instars. The mature larva forms a prepupa, and then a pupa, which undergo metamorphosis to produce the adult. Existing in both grub-like and winged forms allows the fly to maximally exploit ephemeral food sources without tying its fate to them.

Earlier work had shown that the larval and adult forms are patterned by the same “signaling systems,” or chains of biochemicals that transfer a signal from receptors on the surface of cells to target genes within cell nuclei.

What scientists didn’t understand was how the same signaling systems could orchestrate the formation of a larva in one case and the adult fly in the other.

The Duncans, working with collaborator Eric Baehrecke, PhD, of the University of Massachusetts Medical School and graduate student Xiaochun (Joanna) Mou were able to show that a gene expressed only in the pupal stage redirects signaling systems so that they activate a different set of target genes than in earlier stages.

This gene is itself controlled by a steroid hormone that turns on many other genes as well. So insect metamorphosis, triggered by a hormone, resembles puberty, the human analog of metamorphosis, which is also triggered by hormones.

A wholesale change

In 2011, Michael Akam and Anastasios Pavlopoulos, scientists at the University of Cambridge, published a paper in PNAS that described what happened when they artificially turned on a regulatory gene at different stages of a fly’s metamorphosis.

Using microarrays that detected the products of gene activity, they found that at every stage of metamorphosis, the regulatory gene subtly increased or decreased the expression of hundreds of downstream genes. But the kicker was that at different stages of metamorphosis, different downstream genes were turned on.

“They found 870-some target genes,” Ian Duncan says, “and among those 870, roughly 200 were induced in the larva, more than 400 were induced in the prepupa, and 350 were induced in the pupa, but the thing is, the genes controlled at each stage were almost completely different. So they realized there were global changes of rules from one stage to the next.”

“It’s as if two teams were playing soccer,” Dianne Duncan says, “and at halftime the referee comes out and hands out a new set of rules. Now you’ve got the same players, the same field, the same goals, but the teams are playing hockey not soccer. The rules are different, so the game is different.”

Akam and Pavlopoulos ended their article in PNAS by saying that more research was needed to understand how this repurposing of signaling pathways happens. The Duncans, in reply, are publishing their paper in the same journal.

Throwing two switches

The Duncans focused on a gene called E93 that is turned on by steroid pulses, but only at the pupal stage. “It is required for all patterning and production of new structures in the pupa, but it doesn’t play any role in making the larva,” Ian Duncan says.

Ian and Dianne Duncan

Two switches must be thrown to turn on a target gene (Distal-less) that induces the formation of black spots on the legs called bracts, one of many changes in the transformation of a fruit fly pupa to an adult. One (left) ensures that the target gene is turned on only in the pupa. The other (right) controls where it turns on in the pupa.

To understand in detail what E93 was doing in the fly, the Duncans chose a simple and well understood patterning process: the activation of a target gene called Distal-less that makes dark spots near the fly’s leg bristles called bracts.

The target gene is activated by a well-studied signaling pathway — the epidermal growth factor receptor (EGFR) pathway. “The EGFR signal pathway is used all over the place in the fly,” Ian Duncan says. “It’s used for different things at different times.”

To demonstrate that E93 had to be activated before the EGFR pathway could turn on the target gene, the Duncans looked at flies with mutated E93 genes.

“In the mutant that doesn’t have this gene, cells don’t respond to the signaling pathway, and bracts fail to form,” Ian Duncan says.

Further experiments showed that E93 and EGFR signaling are both needed to turn on the target gene Distal-less. E93 tells Distal-less when to turn on and EGFR signaling tells it where to turn on. Having to throw two switches ensures that the target gene is activated at only the right time and place.

Turning on bracts at the wrong time

As the “two switch” idea suggests, it isn’t possible to activate Distal-less at the wrong stage by artificially turning on either E93 or EGFR signaling. Only turning on both E93 and EGFR signaling activates Distal-less.

“If both E93 and EGFR signaling are active, the Distal-less gene will turn on in the larva even though it's the wrong time,” Ian Duncan says.

“This finding was important because it showed that E93 can make cells behave as though they’re in a pupa even if they’re not. E93 says it's the right time.”

Bracts and brains

Bracts aren’t very sexy, and in fact, the Duncans say, nobody knows what they do. They’re just a convenient anatomical feature to study.

The Duncans plan next to study the effect of E93 on the fruit fly brain.

“We know enough now to know that E93 strongly affects brain remodeling in the pupa. Presumably E93 is doing the same thing in the nervous system that it is doing in the leg: it’s affecting the responsiveness of genes,” Ian Duncan says.

And there is again a tantalizing parallel to human physiology. Not only are the frontal lobes remodeled during puberty, that’s also when diseases such as bipolar disorder and schizophrenia tend to manifest.

“There’s so much cell death and rewiring during this period,” Dianne Duncan says, “it’s astonishing that we get through it as well as we do."

“There’s even a human homolog of E93 called LCOR (ligand-dependent co-repressor) that is also involved in steroid signaling,” she says.

Scientists don’t know yet what LCOR does biologically, but odds are they will soon be looking to see.

Study extends the ‘ecology of fear’ to fear of parasites

Diana Lutz — 2012-02-24 00:00:00

Jonathan Myers/WUSTL

No, those aren’t specks of dirt. Those are larval ticks on a piece of duct tape collected during a study to see whether potential hosts avoid areas with lots of ticks.

Here’s a riddle: What’s the difference between a tick and a lion? The answer used to be that a tick is a parasite and the lion is a predator. But now those definitions don’t seem as secure as they once did.

A tick also hunts its prey, following vapor trails of carbon dioxide, and consumes host tissues (blood is considered a tissue), so at least in terms of its interactions with other creatures, it is like a lion — a very small, eight-legged lion.

Jonathan Myers/WUSTL

The blowup of the first image that you really didn't want to see.

Ecologists are increasingly finding it useful to think of parasites, such as ticks, as micro-predators and have been mining predator-prey theory for insights into parasite-host ecology.

One of those insights is that predators don’t just graze at will, and prey aren’t just so many steaks in a freezer. Instead, prey make predators work for dinner by moving elsewhere, being vigilant, flocking together or taking other defensive measures.

This notion that prey are not victims but players, as strongly motivated by fear as the predators are by hunger, is called the ecology of fear.

Work at Washington University in St. Louis, just published in EcoHealth, shows that the ecology of fear, like other concepts from predator-prey theory, also extends to parasites.

Raccoons and squirrels would give up food, the study demonstrated, if the area was infested with larval ticks. At some level, they are weighing the value of the abandoned food against the risk of being parasitized.

This new understanding of the interaction between ticks and host animals has implications for human health because the ticks are vectors of several newly emerging diseases. The more we know about what determines the distributions of ticks in their environment, the better prepared we will be to avoid human exposure to these diseases.

Do host animals fear ticks?

The study’s first author, Alexa Fritzsche, collaborated with Brian Allan, PhD, now an assistant professor of entomology at the University of Illinois at Urbana-Champaign.

FRITzsche

Two young raccoons visiting a feeding tray for breakfast become unwitting participants in the study.

By the time Allan finished his postdoctoral fellowship at WUSTL, he had acquired a reputation as the tick man of Tyson Research Center, the university’s biological field station.

So it was only natural that when Fritzsche, then Allan’s summer research technician, was given time to do research of her own, she decided to see if the ecology of fear extends to ticks.

Fritzsche now is a doctoral candidate in the Odum School of Ecology at the University of Georgia and is studying the role that animal behavior plays in determining the risk of parasitism

Near St. Louis, the most prevalent tick is Amblyomma americanum, called the lone star tick because the adult female has a white splotch on her back. Its larval stage heavily parasitizes small mammals, such as gray and fox squirrels and the common raccoon.

Because the ticks can weaken an animal either by exposing it to pathogens or simply by consuming vast quantities of its blood, it made sense to ask whether the host animals were aware of the ticks and able to avoid them.

“It really comes down to natural selection,” Fritzsche says. “There is a cost to being parasitized, and if you don’t develop ways to detect the parasite and avoid it, you’re not going to do well in the long term.”

What will they give up to avoid ticks?

Allan

Dragging for ticks. Obligatory gear includes white clothing, gaiters over the boots and tucked in hair.

But what makes sense is not always true. To find out whether host animals avoided ticks, Fritzsche set up an experiment at Tyson, a 2,000-acre outdoor laboratory for ecosystem studies largely covered by oak-hickory forest that is representative of many of the natural areas in Missouri.

The study was designed to take advantage of the fact that lone star tick larvae (sometimes called “seed ticks”) emerge from eggs in the leaf litter in mid- to late-summer and tick densities increase as more and more ticks emerge.

Larval tick densities were measured by dragging a cloth to which “questing” ticks became attached, and counting and identifying the ticks in the laboratory.

“The tick larvae are only about the size of a poppyseed,” Fritzsche says, “but they are present in such great numbers that you can look down and see a mass of them on the ground.

Fritzsche counting ticks at the Tyson Research Center.

“When you dragged over one of these ‘tick bombs,’” she says, “the ticks could scatter across the cloth within seconds. I walked with a loop of duct-tape around my hand and as soon as I saw a mass, I’d hit the cloth with the duct tape and they’d be stuck on the tape.”

The animals’ response to the ticks was measured by how much food they abandoned, called the giving-up-density (GUD). This metric for assessing tradeoffs between foraging benefits and predation risks is well-established in predator-prey ecology but has only recently been used to assess the ecology of fear in host-parasite interactions.

Run for your lives

Contrary to Fritzsche’s expectations, the animals didn’t abandon the ground-level trays as soon as the ticks began to emerge.

Over the course of the study, tick numbers increased — but in a patchy fashion. Some sites had only one tick per 60 square meters; others had 667.

Now, the animals began to abandon more seed from trays at sites with high tick densities regardless of whether they were on the ground or in a tree. The result suggests that the host animals may recognize the threat of parasitism and adjust their patterns of foraging accordingly.

CDC

The Center for Disease Control’s most recent map for reported cases of Ehrlichiosis chaffeensis, the most common of the emerging diseases carried by the lonestar tick (Amblyomma americanum). Oklahoma, Missouri and Arkansas account for 35 percent of all reported E. chaffeensis infections. The incidence of ehrlichiosis has gone steadily up since the disease became reportable in 2000 but thankfully the case fatality rate has declined.

“We thought that they might abandon more seed on the ground than in the tree because ticks are confined to the ground, so we expected more of a local trade-off in foraging,” Allan says. “It turned out that the hosts were actually avoiding entire areas of high tick densities, suggesting potentially an even stronger response to the risk of parasitism than we initially hypothesized.”

Apparently people have underestimated both the ticks and their furry hosts, which far from blundering about obliviously, are wary of threats to their health the size of the period at the end of this sentence.

Fritzsche is willing to take the ecology of fear even farther — to include host responses to infections with micro-organisms as well as micro-predators.

Running a temperature helps some amphibians fight parasites such as viruses and fungi. As cold-blooded animals, they can’t raise their temperature on their own, but some amphibians will go to the highest rocks where the sun burns brightest to acquire a “behavioral fever” that helps them fight these illnesses.

“Some people are reluctant to attribute this level of ‘awareness’ to wild animals,” Allan says, “but ecologists have established quite clearly that prey will go to great lengths to avoid predation. Given the substantial cost of parasitism to wildlife, it wouldn’t be surprising if hosts actively adjust their behaviors to reduce this burden.”

After all, it isn’t that different from washing your hands.

New model provides different take on planetary accretion

Tony Fitzpatrick — 2012-02-27 00:00:00

T. A. Rector & B. A. Wolpa, NOAO, AURA,

This image of the Eagle Nebula, made with data from the Kitt Peak telescope, corresponds more closely to the authors’ model than to the traditional model. In their model planets form in a cold, three-dimensional cloud of gas and dust.

The prevailing model for planetary accretion, also called fractal assembly, and dating back as far as the 18th century, assumes that the Solar System’s planets grew as small grains colliding chaotically, coalescing into bigger ones, colliding yet more until they formed planetesimals. The planetesimals then collided until they formed planets as varied as the Earth and Jupiter.

The model assumes that this occurred in an extremely hot (as high as 1,600 degrees Celsius) environment for the inner Solar System, fostered by a dusty, two-dimensional disk post-dating the Sun.

The basic modern model, developed by Russian astronomer Victor Safronov, and further developed by planetary scientist George Wetherill, is called the Solar Nebular Disk Model and was made available in English in the early 1970s. It has remained essentially the same over the past 40 years.

ESO/L. Calçada

The planetary scientists say that the solar system we know today could not have formed out of a flat, hot disk that postdates the Sun, like the one shown in this artist's impression.

But not everyone is convinced the model is correct. How could such a chaotic, haphazard process as fractal assembly lead to the regularities of the Solar System with all of the planets in a single plane, rotating in the same sense, spinning and orbiting around the Sun?

For the discontents, a new model, offered by Anne Hofmeister, PhD, research professor of earth and planetary sciences and Robert Criss, PhD, professor in earth and planetary sciences at Washington University in St. Louis, presents a different scenario. Their explanation is published in the March issue of Planetary and Space Science.

Using classical physics, the laws of thermodynamics and mechanics, Hofmeister, with assistance from Criss, presents an accretion model that assumes a three-dimensional (3-D) gas cloud. This pre-solar nebula collapses and forms the Sun and planets at essentially the same time, with the planets contracting toward the Sun.

The temperature is cold, not hot. The thermodynamic and mechanical model of 3-D accretion explains planetary orbits and spins, unlike the 2-D model, which does not.

Hofmeister and Criss explain compositional gradients across the Solar System in terms of lighter molecules diffusing faster than heavier ones. The model connects planet mass to satellite system size via gravitational competition.

Explaining planetary orbits and spins

“This model is radically different,” Hofmeister says. “I looked at the assumption of whether heat could be generated when the nebula contracted and found that there is too much rotational energy in the inner planets to allow energy to spill into heating the nebula.

“Existing models for planetary accretion assume that the planets form from the dusty 2-D disk, but they don’t conserve angular momentum. It seemed obvious to me to start with a 3-D cloud of gas, and conserve angular momentum. The key equations in the paper deal with converting gravitational potential to rotational energy, coupled with conservation of angular momentum.”

No energy left over for heat

“In the new model, heat production is not important in planetary formation,” Hofmeister says.

Criss says the prevailing notion that gravitational collapse is a hot process is a mis-interpretation of thermodynamics. He offers an analogy of a beaker of water placed outside in the winter. It slowly starts to freeze. Freezing water actually releases a latent heat, he says, because order (ice, a crystal) is being made from disorder (liquid).

The heat released is considerable, but it cannot warm the beaker because “it’s released only as fast as the environment will take it away,” Criss says. “If the heat would warm the water above 32 degrees Fahrenheit, the ice would melt. People clinging to the old accretion models want to make the ice and heat the beaker, too.”

Gravitational competition

The authors say 2-D models don’t explain why the inner Solar System is comprised of rocky planets and the outer gas giants.

“The first thing that happens in planet accretion is forming rocky kernels,” Hofmeister says. “The nebula starts contracting, the rocky kernels form to conserve angular momentum, and that’s where the dust ends up. Once rocky kernels exist, they attract gas to them, but only if the rocky kernel is far from the Sun, can it out-compete the Sun’s gravitational pull and collect the gas, as did Jupiter and its friends.

“But if the rocky kernel is close, like the Earth’s, it can’t out-compete the Sun. We describe this process as gravitational competition. This is why we have the regularity, spacing, and graded composition of the Solar System.”

Gravitational competition also offers a new view of formation of the moon that does not require an extremely low probability giant impact.

Not limited to the Solar System

Hofmeister says there is a continuum between single stars, binary stars, multiple stars, planets and even extrasolar planets.

“In all cases, the process is gravitational accretion of these cold, 3-D clouds making things contract and spin out, and that’s where the energy comes from,” she says. “It’s all happening in very cold temperatures, in 3-D instead of 2-D.”

Criss says there is plenty of observable evidence that the 2-D model is wrong.

“It patently doesn’t make sense that a bunch of random collisions between heavy, solid objects are going to produce a Solar System with planets orbiting the Sun in a beautiful plane, with everything having upright spins,” he says. “That’s like setting off a nuclear bomb and expecting all the trees in the world to end up neatly stacked.

Moreover, the Hubble pictures show stars being born in the Eagle nebula, and they’re formed in a cold 3-D cloud.”

Mirica receives Sloan Research Fellowship

2012-02-23 00:00:00

Mirica

Liviu M. Mirica, PhD, assistant professor in the Department of Chemistry in Arts & Sciences at Washington University in St. Louis, has won a prestigious research fellowship from the Sloan Foundation.

Awarded annually since 1955, the fellowships are given to early-career scientists and scholars whose achievements and potential identify them as rising stars — the next generation of scientific leaders.

Administered and funded by the Sloan Foundation, the fellowships are awarded in close cooperation with the scientific community. To qualify, candidates must first be nominated by their peers and are subsequently selected by an independent panel of senior scholars. Fellows receive $50,000 to be used to further their research.

The foundation awarded 126 fellowships this year, including 22 in chemistry. Mirica’s was the only one awarded to Washington University this year.

Mirica will use the funds to develop novel catalysts that will be able to efficiently convert the greenhouse gases methane (CH4) and carbon dioxide (CO2) into useful chemicals.

He proposes to use catalysts that consist of custom-designed organic molecules bound to metal centers — holding them like a glove holds a ball, and thus controlling their reactivity with molecules such as CH4 and CO2.

Methane, the main constituent of natural gas, is probably the most abundant organic molecule on Earth but is difficult to transport because it is gaseous at normal pressures and temperatures. If it could be converted into longer-chain hydrocarbons, it could become a significant source of energy as petroleum reserves diminish.

Methane conversion requires an oxidant and Mirica is proposing to design a catalyst that will employ dioxygen (O2) as an environmentally benign oxidant.

In addition, Mirica is interested in converting the CO2 made by burning fossil fuels — including methane — into a useful molecule, such as a liquid fuel. The difficulty here is that CO2 is very stable, which is why everything burns to CO2 in the first place.

But Mirica feels it should be possible to “close the cycle,” by recovering the CO2 produced by burning fossil fuels and converting it back to a liquid fuel, such as methanol (CH3OH), which would in turn produce CO2 when it was burned.

The catalysts would speed up the reactions by changing the way the molecules interact with one another, but each turn of the cycle would still demand the input of energy, which Mirica hopes eventually to supply from a renewable source, such as the sun, so that the overall process would be carbon-neutral.

Mirica joined the WUSTL faculty in 2008 after a National Institutes of Health postdoctoral fellowship at University of California, Berkeley.

Mirica earned a bachelor’s degree in chemistry in 1999 from the California Institute of Technology and a PhD in chemistry in 2005 from Stanford University.

The Alfred P. Sloan Foundation is a philanthropic, not-for-profit grant-making institution based in New York City. Established in 1934 by Alfred Pritchard Sloan Jr., then-president and chief executive officer of the General Motors Corp., the foundation makes grants in support of original research and education in science, technology, engineering, mathematics, and economic performance.

WUSTL professor Weinberger receives NSF CAREER award

2012-02-16 00:00:00

Weinberger

Kilian Q. Weinberger, PhD, assistant professor of computer science & engineering in the School of Engineering & Applied Science at Washington University in St. Louis, has won a prestigious Faculty Early Career Development Award (CAREER award) from the National Science Foundation (NSF).

The awards are given “in support of the early career-development activities of those teacher-scholars who most effectively integrate research and education within the context of the mission of their organization” with the goal of “building a firm foundation for a lifetime of integrated contributions to research and education.”

Eighteen CAREER awards are currently “active” at Washington University in St. Louis.

Weinberger will use the projected five-year, $440,000 award to perfect a type of machine learning that could be useful for a broad array of applications.

Weinberger’s CAREER project, “New Directions for Metric Learning,” seeks to solve one of the fundamental problems of machine learning: how to compare individual texts, images or sounds. If an algorithm could perfectly determine whether two instances of a data type are similar or dissimilar, most subsequent machine learning and data analysis tasks would become trivial, he says.

“A common similarity measure between two data instances is the total squared difference of their attributes,” Weingberger says. “With this metric, similar instances end up close together and dissimilar instances are far apart. Although this distance is a convenient and intuitive measure of similarity, it ignores the fact that the meaning of similarity is inherently task-and data-dependent.

“For example, one person might be interested in organizing articles by author, whereas a second might organize them by topic. Given the nature of their respective tasks, both should use very different metrics to measure document similarity.”

To deal with this difficulty, domain experts adjust their data representations by hand — but this is not a robust approach. It would be better if a software program could “learn” the metric (or data representation) that works best for each specific application, and this is the approach Weinberger plans to take.

“Such a metric can be learned,” Weinberger says, “by mapping the digital representation of the data into a high-dimensional representation, which is then deformed to move similar points closer together while keeping dissimilar data instances apart.

Weinberger’s birthday cake, made by a research colleague, is a schematic representation of data where similar points are pulled close together and dissimilar points moved apart by the deformation of the space they occupy. On the cake, the green points have moved closer to the green dot in the center, whereas the blue and red points have moved farther away from it.

"For illustration, imagine a sheet of paper with little dots. In a three-dimensional space you can fold the piece of paper such that any two points become close. If you want to move many pairs of points together at the same time, you might need several thousand dimensions. “

Weinberger expects medical screening will be one of the first applications for the new metric learning methods.

For the educational component of his grant, he plans to develop a K-12 curriculum module about machine learning, which he hopes will show students how fundamental mathematics is to the technologies they use in daily life.

Weinberger joined the WUSTL faculty in 2010 after a stint as a research scientist at Yahoo Research in Santa Clara, Calif., where he worked on spam filtering algorithms, multimedia search, high-dimensional data analysis and machine learning. His work on metric learning has won several outstanding paper awards.

Weinberger earned his bachelor’s degree in mathematics and computer science in 2002 from Oxford University in England, and his master’s and doctoral degrees in 2004 and 2007 in computer science from the University of Pennsylvania.

Less lively aluminum baseball bats change game

Diana Lutz — 2012-02-17 00:00:00

Baseball is considered relatively safe, but its reputation was established in the era of wooden bats. Aluminum bats, introduced in the 1970s, had an enormous “trampoline effect” and made the game more dangerous.

A 90-mph pitch could come off a lively aluminum bat at 108 mph and reach the pitcher 0.375 seconds later, leaving him no time to react when the ball was hit right back at him.

In fact, several high school players were severely injured and at least two killed by scorching line drives.

In 2003, 18-year-old Brandon Patch was killed by a line drive when he was pitching for his team in Montana. In 2009, his family won a verdict against the maker of the Louisville slugger for his death.

In 2010, a 13-year-old Vermont pitcher also was killed by a line drive.

Last year, the National Collegiate Athletic Association required all aluminum bats used in college play to meet a new performance standard designed to limit the exit speed of the ball off the bat. This year, the National Federation of State High School Associations also has implemented the new standard.

With spring training beginning at all levels this month, David A. Peters, PhD, the McDonnell Douglas Professor of Engineering in the Department of Mechanical Engineering & Materials Science at Washington University in St. Louis, explains the new standard.

WUSTL baseball head coach Steve Duncan, and WUSTL hitting coach and Rawlings category manager for bats Kyle Murphy also comment on the new bats and how they have affected play.

First the balls

Peters, an avid baseball fan, has made 32 video vignettes about the physics of baseball for Cardinal Nation, the St. Louis Cardinals fan club.

“Three things come into play when a baseball comes off a bat,” Peters says. “The speed of the balls coming in; the speed the bat’s being swung — the speed of the bat hit; and then how much energy is lost in that collision.”

The energy lost in the collision depends on how bouncy the ball is and how springy the bat. That bounciness, or springiness, is technically known as the coefficient of restitution, a measure of how much energy the ball or bat gives back after being deformed by an impact.

As a general rule, wood bats made of white ash, the traditional material, give very little and store little energy. But what little they store they give back efficiently. The ball, on the other hand, distorts a lot under impact but is relatively inefficient in giving it back, losing the kinetic energy as heat. This is why a game played with wood bats is relatively safe.

But players are always trying to figure an angle, Peters says.

In the early days of the game, it was often the ball that was “cooked” or “juiced,” so in the late 1960s a standard was introduced to limit variations among balls.

The rule is that a ball shot from an air cannon at 85 feet per second at a wall of northern white ash must rebound with a speed of between 43.7 and 49.1 feet per second.

That gives it a coefficient of restitution of about 0.55, meaning the ball loses in the impact roughly 70 percent of the energy it had coming in.

In contrast, a golf ball is much bouncier; it has a coefficient of restitution of about 0.78.

Then the bats

Hot bats became an issue when aluminum bats were introduced in the 1970s. Because aluminum bats are lighter, they can be swung faster than a wooden bat, and that made the balls come off faster.

The big difference between the wooden and aluminum bats, however, was again the coefficient of restitution, called the trampoline effect in the case of the bats.

The hollow aluminum bats flex more when they’re hit and allow the bat to stay in contact for a longer time, imparting more energy to the ball.

Peters says we’ve all seen the difference this makes in the sport of pole vaulting. The poles, like the bats, were originally made of ash but are now made of tubular aluminum.

“The old poles were rigid,” he says, “but now the pole bends halfway down and springs back, flipping the vaulter over the bar.

“Aluminum bats can be engineered to have any amount of rebound one wants by designing the thickness and shape distribution of the bat,” he says.

In fact, after the introduction of aluminum bats, bat designers went a bit overboard. Bats made of titanium, for example, had such an enormous trampoline effect that they were quickly banned.

Another troublesome design that resulted in law suits was the “Air Attack” bat made by Louisville Slugger. It has a pressurized bladder inside that compresses on impact and then expands fast enough to help propel the ball.

http://youtu.be/ww83-wXCn1o

The new bat standard

The old standard for bats, Peters explains, was the Ball Exit Speed Ratio, or BESR standard. A simple ratio, it consisted of the speed of the ball coming in divided by its speed going out.

“Now they’re saying that doesn’t really tell you much about the bat, because many factors contribute to those speeds,” Peters says.

The new standard, the Bat-Ball Coefficient of Restitution, or BBCOR, includes the same speed ratio but adds a correction for the coefficient of restitution of the ball used in the test and another correction for the coefficient of restitution of the bat.

According to the standard, a bat’s BBCOR can be no higher than 0.500, meaning that a ball will give up half of its energy in its collision of the bat.

The effect of the standard is to deaden aluminum bats, making them perform more like the traditional white ash bats —but not quite.

According to lab studies, the BBCOR of an old BESR aluminum bat is about 15.5 percent higher than the BBCOR of a wood bat while the new aluminum bats have a BBCOR 10.7 percent higher than wood bats.

Peters, for one, isn’t sorry to see the new standard put in place. Baseball has been and should remain a game of strategy rather than of speed, he says.

What it means for play

At a clinic for St. Louis-area high school coaches Feb 11, Duncan spoke about the effects the new bats had on NCAA play last year.

Steve Duncan with data from Gary Brown, NCAA

Home runs per game peaked in the last three years in which the NCAA used BESR bats bats (2007-2010). Wood bats were last used in the NCAA in 1973.

In the last three years in which the NCAA used BESR bats, runs increased 14 percent and home runs increased by 38 percent, Duncan says. “In general, the BESR bats shifted the advantage from the defense to the offense.

“The BBCOR bats diminish offense. If statistics are a guide, they effectively take the offensive side of the game back to the 1970s,” Duncan says. “We’re seeing nearly the same statistics as in 1973, the last year that wood bats were used in the NCAA.”

In general, he told the coaches, expect:

Quicker games;
Less offense;
Need for better hitting fundamentals, players must swing; faster and more accurately to get the same results;
Increased emphasis on speed;
Increased emphasis on defense;
Increased emphasis on pitching; and
Need for improved strength and coordination; bat is weaker so players need to be stronger.

Steve Duncan with data from Gary Brown, NCAA

One nonobvious consequence of the change to BBCOR bats in the NCAA is that games are now half an hour shorter than they were the last year BESR bats were used.

“I’m a fan of the new regulations,” Duncan says. “By reducing the margin of error, they benefit the good players at the expense of players who had poor hitting fundamentals but were saved by a bat that could perform miracles.”

How the bats are made

According to Murphy, the challenge with the BESR bats was to make the walls as thin as possible to get the most rebound. “And of course you could make the walls thinner with higher grades of alloy and then with composites when they came into the game,” he says.

“In order to pass BBCOR, you had to make the walls much thicker. There are a couple of ways of doing that. Some makers have put metal rings inside the bats. Like putting cinder blocks under a trampoline, that limited the rebound of the bat.

“At Rawlings, we took a different approach,” he says. “We used what’s called a double-butting procedure, and the bat is thin-walled all the way up to the sweet spot, or where the BBCOR test is taken. It’s a thicker wall in that region and then we thin it out again at the end.

“That way, BBCOR bats are better balanced. We’re trying to make the best-balanced bat on the market. The more balanced the bat, the faster the bat speed, the faster the bat speed, the farther the ball will go.”

Murphy also likes what the new standard is doing to the game.

“I think it really brings pitching back into the game,” he says. “It’s going to make the player a whole lot better. There’s such a thing as an ‘aluminum bat swing,’ and that was guys who weren’t mechanically right with their swings but could get away with it because they could hit singles or doubles off their hands or off the end of the bat.

“Now you have to focus on your fundamentals because you’re not going to get away with a ball off the hands being a single anymore.

“It’s also good for scouting,” he says, “because they can really evaluate which players are going to be able to transition to a wood bat in the pros.

“It’s a different game now with BBCOR, but it’s all for the better,” Murphy says.

Engineering Week on campus begins Feb. 19

2012-02-15 00:00:00

The School of Engineering & Applied Science at Washington University in St. Louis will host a week of special events beginning Sunday, Feb. 19, to inspire current and future engineers.

WUSTL’s EnWeek is one of many similar celebrations taking place at engineering schools across the country under the auspices of the National Engineers Week Foundation.

The National Engineers Week Foundation, a coalition of more than 100 professional societies, major corporations and government agencies, is dedicated to ensuring a diverse and well-educated future engineering workforce by increasing understanding of and interest in engineering and technology careers among young students.

Engineers Week also raises public understanding and appreciation of engineers’ contributions to society. Founded in 1951, engineers week is among the oldest of America's professional outreach efforts.

On Sunday, Feb. 19, the engineers will let off steam by decorating hard hats with stickers and rhinestones and making wallets out of duct tape on the South 40.

The remainder of the week is packed with fun and informative events related to engineering and WUSTL’s engineering school.

Among the activities students will participate in throughout the week are:

games of “Capture the Flag” with Nerf guns in and around Lopata, Urbauer, Bryan and Jolley halls;
a hunt for the “golden mouse” throughout campus;
attending a fair where students will learn about undergraduate research positions in university labs;
a paper airplane competition in which students design and test their own creations in Lopata gallery;
a penny collection for charity; and
a co-ed talent show in which students show their theatrical side.

On Friday, Feb. 24, featured speaker television host Deanne Bell will describe her journey as an engineer at 7 p.m. in the Laboratory Sciences Building Auditorium, Room 300.

Bell

After graduating from WUSTL with a degree in mechanical engineering in 2002, Bell began her career as an aerospace engineer, but went on to appear on PBS’ “Design Squad,” Discovery Channel’s “Smash Lab” and National Geographic’s “The Egyptian Job.”

The student organization Engineers Without Borders selected Bell as its speaker, remarking that she defies the stereotype of a “typical engineer” and exemplifies EnWeek’s mission of promoting a diverse and well-educated engineering workforce.

Bell’s talk is free and open to the public.

An additional component of National Engineer’s Week is "Introduce a Girl to Engineering Day," designed to introduce girls to engineering professions. To close EnWeek at WUSTL, the Society of Women Engineers (SWE) is offering “Girls Day” Saturday, Feb. 25.

Local high school girls have been invited to campus for a day devoted solely to women engineers. The girls may choose to have dinner with SWE members on the South 40 the night before and, if they like, spend the night in a resident hall.

On Feb. 25, they will attend seminars and hands-on activities led by engineering faculty and student groups. After lunch, they will team up for Engineering Olympics, a series of mini design and communication projects.

The day will end with a panel discussion featuring women in engineering, including an undergraduate student, a graduate student, a faculty member and a representative from admissions.

The week’s events are sponsored by the WUSTL student organizations EnCouncil; Engineers Without Borders; the WUSTL chapter of the Society of Professional Engineers; Student Union; and the Society of Women Engineers.

Additional sponsors are the Woman’s Club of Washington University; the Engineering Library; and the School of Engineering & Applied Science.

For more information about engineering week events, including dates and times, visit: engineering.wustl.edu/engineersweek.

Saturday Science looks at unusual experiments

2012-02-15 00:00:00

The progress of physics requires the collaboration of both experimentalists and theorists; only the rare physicist, such as Enrico Fermi, has been successful at both lines of work.

Experimental physicists often exercise great ingenuity to arrange instrumented events that can either verify or falsify the clever ideas of their theoretical friends, who return the favor by laboring to fold the experimentalists' most improbable findings into their theories.

At Washington University in St. Louis this semester, the Department of Physics and University College, both in Arts & Sciences, will describe a few of the experimentalists' greatest successes. Four lectures on great physics experiments will be held at 10 a.m. on four consecutive Saturday mornings, March 10–31, in the Hughes Lecture Room, Room 201 in Crow Hall.

Presented by faculty members of the physics department and tailored for the general public, the lectures are free and open to the public.

The Saturday Science lectures have been organized since their inception 19 years ago by Michael Friedlander, PhD, professor of physics.

Friedlander

Friedlander, an experimentalist who studies cosmic rays and infrared and gamma-ray astronomy, has also written about pseudoscience and the conduct of science. He feels that scientists have an obligation to engage the public.

“As scientists,” he says, “we have an obligation to explain to the non-expert public what we are doing, what is exciting about our findings and where we think all of this may lead.

“In this way, we would hope that the public would gain some understanding of the methods of science, be willing to continue to support our efforts and will also not try to impose ideological restrictions to what we may study.

“History shows that none of this should be taken for granted,” he says.

The schedule

March 10, “The Discovery of Cosmic Rays and What They Are,” Martin Israel, PhD, professor of physics

This year, 2012, is the centennial of the discovery of cosmic rays – ionizing radiation bombarding the Earth from space. Israel will describe the early balloon observations by Victor Hess, who showed that the radiation was coming from space rather than originating on Earth.

TIGER, a WUSTL and NASA balloon-borne experiment to measure the elemental abundances of galactic cosmic rays.

Twenty years later, through his worldwide cosmic ray survey, WUSTL’s Arthur Holly Compton was able to show that the cosmic rays were not “rays” but rather were charged particles. Meanwhile, in studies of cosmic-ray particles in the laboratory, Carl Anderson found a positively charged electron — the theoretically-predicted “positron,” and in 1936 Hess and Anderson shared the Nobel Prize in physics.

March 17 “The LHC and the search for the Higgs,” Michael C. Ogilvie, PhD, professor of physics

An essential component of experiments that explore the internal structure of atomic nuclei are beams of high-speed nuclei. These are accelerated and made to collide. Debris from their collisions is examined and provide the clues being sought.

A simulation of the debris that would result if a collision at the collider in Geneva did produce a Higgs particle.

Ogilvie will describe experiments in progress at the Large Hadron Collider (LHC) in Geneva, where the existence of the predicted Higgs particle might be demonstrated.

March 24, “The Lamb Shift,” John Rigden, PhD, adjunct professor of physics

Rigden will describe the Lamb Shift, named for Willis Lamb who was awarded the Nobel Prize for experiments that explored the internal energy of the hydrogen atom.

March 31, “The Ingenious Experiments of Baron Roland von Eötvös,” Ramanath Cowsik, PhD, professor of physics and director of WUSTL’s McDonnell Center for the Space Sciences

The Eötvös experiment, planned by Baron Roland Eötvös in the early years of the 20th century, provides deep insights into the nature of gravity, and Einstein drew on these experimental observations as he formulated his General Theory of Gravitation.

For more information, contact Sarah Hedley at (314) 935-6276 or visit physics.wustl.edu. Click “Seminars/Events” and then “Saturday Lectures.”

Military service changes personality, makes vets less agreeable

Gerry Everding — 2012-02-09 00:00:00

It’s no secret that battlefield trauma can leave veterans with deep emotional scars that impact their ability to function in civilian life. But new research led by Washington University in St. Louis suggests that military service, even without combat, has a subtle lingering effect on a man’s personality, making it potentially more difficult for veterans to get along with friends, family and co-workers.

“Our results suggest that personality traits play an important role in military training, both in the sort of men who are attracted to the military in the first place, and in the lasting impact that this service has on an individual’s outlook on life,” says study lead author Joshua J. Jackson, PhD, an assistant professor of psychology in Arts & Sciences.

Published in the journal Psychological Science, the study found that men who have experienced military service tend to score lower than civilian counterparts on measures of agreeableness — a dimension of personality that influences our ability to be pleasant and accommodating in social situations.

The study confirms that the military attracts men who are generally less neurotic, less likely to worry, less likely to be concerned about seeking out novel experiences. When compared with men in civilian pursuits, those entering the military also are more aggressive, more interested in competition than cooperation and less concerned about the feelings of others, the study finds.

"Military recruits are a little less warm and friendly to begin with and the military experience seems to reinforce this — as after service, men score even lower on agreeableness when compared to individuals who did not go into the military,” Jackson says. “Interestingly, this influence appears to linger long after the soldier has re-entered the workforce or returned to college."

Jackson points out that being less agreeable is not always a negative human trait. While it may make it more challenging to maintain positive relationships with friends and romantic partners, it can be seen as a positive influence on career success.

“On the flip side,” he says, “people with lower levels of agreeableness are often more likely to fight their way up the corporate ladder and to make the sometimes unpopular decisions that can be necessary for business success.”

Either way, this study offers evidence that experiences in basic training and other military service do shape the way people approach the world.

“These changes in personality appear to be small, but they could make a big difference in the lives of those who have served in the military,” he says.

Jackson’s research is based on a six-year study that tracked the personality traits of a group of young men in German high schools who chose to meet mandatory public service requirements through either military or civilian service.

Co-authored with Felix Thoemmes, Kathrin Jonkmann, Oliver Lüdtke and Ulrich Trautwein, all of the University of Tübingen in Germany, the study is among the first to empirically test whether a particular life experience can truly change an individual’s personality, something that many psychologists have long considered to be unlikely.

As Jackson explains, psychologists generally view personality as one of the most stable and difficult-to-change human traits. While some studies have tracked small changes in personality over time, such as changes related to the aging process, there is little research on why these changes occur, or on what sorts of life experiences might contribute to the changes.

Jackson's research team saw the military as the perfect laboratory in which to test for personality-changing life experiences.

“The whole military experience is sold as an opportunity for a life-changing transformation,” Jackson says. “Recruiting materials of military forces around the world bolster the idea of military experience as being a catalyst for change. For example, recent slogans in the United States, such as ‘Be all you can be,’ ‘Accelerate your life,’ and ‘Aim high,’ all imply that military experiences affect life trajectories.

“It’s one of the few situations in life where an individual’s daily actions and expectations are completely controlled by someone else. Where, from the moment you wake up in the morning until you go to bed at night, someone is actively working to break down anything that’s individual about you and to build up something else in its place.”

Researchers tested the men’s personalities during high school and re-tested them three times in the six years following either civilian or military service. Not surprisingly, all of the participants scored higher on measures indicative of maturity, such as increased conscientiousness and less neuroticism.

And while the military group did show some increases in measures of agreeableness, the change was much lower than that measured for participants in the civilian service group.

“While the military often promises to ‘make a man out of you,’ our analysis suggests that much of the advertised post-military increase in maturity can be attributed to normal changes that most young men experience during this stage of their lives," Jackson says.

"And while military service doesn’t seem to have much impact on other personality traits, such as levels of anxiety or gregariousness, it appears to have a small but significant influence on measures of agreeableness.”

Jackson’s findings may offer a new explanation for why military service members tend to differ from civilians in their rates of divorce, longevity, salaries and health issues.

“Often these differences are interpreted in terms of the social opportunities that either exist or don't exist for military members, but rarely is it suggested that military experience changes something about the person, which then influences these outcomes,” Jackson says.

“It’s not a cut-and-dried issue, but this study shows that changes in personality may be one reason that military service is associated with different rates of important life outcomes, like divorce or occupational attainment.”

Apply now to spend three weeks in China next summer

Thu, 09 Feb 2012 14:37:59 CST

Wikimedia Commons

The Prince’s Residence and Garden from the Qing Dynasty located on the grounds of the Tsinghua University

Reluctant to spend another summer in steamy St. Louis? Consider taking a month to learn about China in China while helping Chinese students learn English.

Frank Yin, PhD, ambassador to Tsinghua University, a partner institution in the McDonnell International Scholars Academy, invites Washington University in St. Louis faculty and students to participate in Tsinghua’s annual English summer camp, which will be held from June 26 to July 13.

Last summer, WUSTL sent seven teachers and eight volunteers to Tsinghua. The same number will attend this year, says Yin, the Stephen F. and Camilla T. Brauer Distinguished Professor of Biomedical Engineering and chair of the department of biomedical engineering in WUSTL’s School of Engineering & Applied Science.

Tsinghua, one of China’s premier universities, is located in northwest Beijing, on the former site of Qing Dynasty royal gardens. The campus retains Chinese-style landscaping as well as traditional buildings.

The English summer camp is an intensive English language experience for Tsinghua students. Each day is devoted to lessons, lectures, and various activities, including seminars, song and dance competitions, and other games.

The camp is for students who have just completed their freshmen year at Tsinghua. The university anticipates about 3,300 students to take part this summer.

The camp’s goal is to increase the students’ interest and enthusiasm in learning English as well as to improve their basic English skills in reading, writing, listening, and speaking.

WUSTL native or near-native English speakers are invited to join the camp as visiting teachers and volunteers.

Visiting teachers will teach English classes, give lectures on topics of interest, and help out with group activities. Volunteers will facilitate lecture discussion seminars and lead group activities, such as competitions involving music, speech and drama.

Teachers should hold at least a master’s degree or be a currently enrolled graduate student, and; volunteers should be currently enrolled undergraduate students.

During the camp’s three weeks, teachers and volunteers will be provided free meals and on-campus accommodations. Teachers will receive a stipend of approximately $2,000 in U.S. dollars and volunteers a stipend of approximately $470 in U.S. dollars.

There will be two days of orientation and team coordination prior to the camp (June 23-24), and both teachers and volunteers arrive in Beijing on June 21 or 22. Transportation between the Beijing airport and the Tsinghua campus will be provided.

To view the camp’s website, visit flc.tsinghua.edu.cn. For more information or to apply, email Yin at yin@biomed.wustl.edu.

The application deadline for teachers is Feb.22. The deadline for volunteers is March 15.

Teaching graduate and postdoctoral students to be successful teachers

2012-02-09 00:00:00

David Kilper

Kristin Powell, a graduate fellow in biology, talks to students Megan Yu and Liz Anterasian during a breakout session in an ecology course. The students were asked to identify the main ideas in a reading about pitcher plants and the next steps the ecologist should take to pursue his research questions. Powell is participating in a pilot project in which graduate students make curricular changes and then learn to evaluate the effect of those modifications on learning. The WUSTAR program is modeled on programs at other universities. If it is successful, the organizers hope to expand it to all of the science, technology, engineering and math disciplines on campus.

Washington University in St. Louis has joined a national experiment to develop a new generation of college science and engineering faculty, one equipped to excel in the classroom as well as the lab.

In 2003, the University of Wisconsin-Madison founded the Center for the Integration of Research, Teaching and Learning (CIRTL). The center’s mission is to prepare science graduate students to be as bold and creative in the classroom as they are in their programs of research.

The CIRTL network has since expanded to 25 research universities, including Washington University. Organizers hope to have as many as 100 members in the next five years.

Supported by the National Science Foundation, CIRTL is working to develop a national faculty in science, technology, engineering and mathematics (STEM). CIRTL focuses on the challenges of improving student learning and increasing diversity in STEM.

CIRTL, says Kathryn Miller, PhD, professor and chair of the Department of Biology in Arts & Sciences, provides a new philosophical and strategic springboard for individual campuses to develop programs aimed at giving graduate students in the sciences, engineering and math the skills and tools to be creative and rigorous in the classroom.

“CIRTL is organized around three core ideas, called the CIRTL pillars: teaching-as-research, learning communities and learning-through-diversity,” Miller says.

A foundational CIRTL concept is that improving one’s teaching boils down to the key question “What have my students learned?” This question, Miller argues, can be addressed in each classroom by adapting the experimental method familiar to scientists: hypothesis generation, experiment, observation, analysis and improvement. This approach is called “teaching-as-research,” Miller says.

“The WUSTL CIRTL learning community will introduce graduate students and postdoctoral fellows to ‘active learning’ and inquiry-based approaches to teaching,” Miller says. “We hope some of them will also participate in ‘teaching-as-research’ projects.”

As an example, she cites the WU-STAR (STEM Teaching-as-Research) internships, a pilot project that is allowing four graduate students to develop teaching-as-research projects in collaboration with The Teaching Center and faculty members Eleanor Pardini, PhD, lecturer in environmental studies and biology, Tiffany Knight, PhD, associate professor of biology, and Joseph Jez, PhD, associate professor of biology.

The WU-STAR interns are making curricular modifications to biology courses being taught this spring. With staff from the Center for Integrative Research on Cognition, Learning and Education (CIRCLE), the interns are learning how to evaluate the effects of these modifications on student learning.

They are also meeting with staff from The Teaching Center for weekly discussions of teaching-as-research. The WU-STAR interns are getting a comprehensive view of teaching-as-research and of teaching as an endeavor among a community of scholars — rather than an isolated experience.

CIRTL organizers envision that graduate students will take on the roles of “fellow,” “practitioner” or “scholar,” depending on the time they can commit to projects. The goal is that 20 percent of graduate students at member institutions be fellows, 10 percent be practitioners and 2 percent be scholars.”

“We’re particularly concerned about the postdoctoral fellows,” Miller says, “because graduate students are required to teach and to participate in training on teaching, but it is less clear how postdoctoral fellows can fit this training into their other responsibilities.”

The CIRTL website cirtl.net provides a virtual forum for formal and informal interactions among registered members of the center.

The website offers online courses about issues related to teaching, a café where people can meet for informal discussions at “coffee hour,” a virtual conference room for formal meetings, CIRTL-casts (webcasts) for one-shot seminars and an exchange program that allows graduate students and postdoctoral fellows who have teaching-as-research projects to present their work at other institutions in the consortium.

To learn more, interested faculty can contact Miller at miller@biology.wustl.edu or (314) 935-6859.

Moynier awarded young scientist honors

2012-02-01 00:00:00

Frédéric Moynier, PhD, 33, assistant professor in the Department of Earth and Planetary Sciences in Arts & Sciences and a member of the McDonnell Center for the Space Sciences at Washington University in St. Louis, has been named the recipient of the 2012 Houtermans Award and the Nier Prize, both given for exceptional work by a scientist younger than 35.

Moynier

“We are excited to have Frédéric recognized for his outstanding work in cosmochemistry and geochemistry,” says Doug Wien, PhD, professor and chair of earth and planetary sciences. “He is an exceptionally talented and hard-working young scientist, and we are fortunate to have him in our department.

“He is always eager to talk about some new scientific development, and working with him is a delight,” Wiens says. “He has accomplished at lot in just a few short years here, so I expect he has many important discoveries ahead of him.”

“Moynier is one of the most brilliant young professors associated with the McDonnell Center for the Space Sciences,” says Ramanath Cowsik, PhD, professor of physics in Arts & Sciences and director of the McDonnell Center.

“He uses primitive meteorites as proxy for the materials out of which the Earth and other planets condensed at the time of their formation a little over 5 billion years ago. His research constitutes an important advance in our understanding of the conditions that prevailed at the time of the formation of the Earth. The center takes great pride in his achievements,” Cowsik says.

The Houtermans Award

The Houtermans Award is given annually by the European Association of Geochemistry (EAG) for exceptional contributions to the field of geochemistry.

In the award citation, the association said Moynier seeks to advance “understanding the chronology of the early solar system, the early differentiation of the Earth, the origin of the volatile elements in terrestrial planets, non mass-dependent isotopic fractionation mechanisms and the nucleosynthesis and the stellar environments at the birth of our solar system.”

‘To reach these goals, Moynier uses isotopic geochemistry tools such as short-lived radioactive nuclides and heavy stable isotopes,” the citation says.

The EAG is a pan-European organization founded to promote geochemical research. The EAG organizes conferences, meetings and educational courses for geochemists in Europe, including the Goldschmidt Conference, which it co-sponsors with the North American Geochemical Society.

Moynier, who was raised in Provence, France, earned a bachelor’s degree in geology in 2002 and a doctoral degree in 2006 from the Ecole Normale Supérieure de Lyon.

The award is named in honor of Friedrich George Houtermans, a Dutch-Austrian-German physicist who made important contributions to geochemistry and cosmochemistry even though, as a Communist in the 1930s, he ran afoul of international politics.

The award will be bestowed on Moynier at the 22nd Goldschmidt Conference in Montreal in June.

The Nier Prize

The Nier Prize is given annually by the Meteoritical Society for outstanding research in meteoritics and closely allied fields.

Moynier was recognized “for significant contributions to understanding the processes that produced isotopic fractionations in the transition metals in solar system materials.”

The Meteoritical Society is a nonprofit scholarly organization founded in 1933 to promote the study of extraterrestrial materials, including meteorites and space-mission-returned samples, and their history.

The award was established in 1995 to honor the memory of Alfred O. C. Nier, an American physicist who pioneered the development of mass spectroscopy. It is supported by a grant given by Nier’s wife, Ardis.

Moynier will receive the Nier Prize at the annual meeting of the Meteoritical Society in Cairns, Australia, in August.

Washington People: Joseph Jez

Diana Lutz — 2012-01-27 00:00:00

Joe Angeles

Joseph Jez, PhD (right), associate professor of biology, and doctoral candidate Soon Goo Lee in the cold room checking a tray to see whether a protein has crystallized in any of its wells. Jez’s lab crystallizes proteins in order to figure out how these little biological machines work.

When Soon Goo Lee, a graduate student in the Jez Lab at Washington University in St. Louis, clicked the mouse button that would reveal whether he had successfully cracked the structure of a new protein, his advisor Joseph Jez, PhD, whipped out his cell phone to record the moment.

Jez, associate professor of biology in Arts & Sciences, wanted a record because he knew how much it meant to Lee.

Jez knew every disappointment and setback Lee had weathered over the past six years: the proteins that wouldn’t crystalize; the proteins that crystallized into ill-formed “blobules”; and the proteins that grew into nice, big crystals but produced “sick” diffraction patterns that couldn’t be “solved” in any reasonable amount of time.

He also knew what it meant because he’d been there himself, standing there with his finger on the mouse button, taking a deep breath as he faced the moment of truth.

“What my lab does is crystallize proteins so that we can see what they look like in three dimensions,” Jez says. “The idea is that if we know the protein’s structure, it will be easier to design chemicals that will target the protein’s active site and shut it down.”

Recently, his lab crystallized a protein crucial to the protozoan that causes the most lethal form of malaria. Now that the protein’s structure is known, it might be possible to design a drug that would block it and prevent the disease without harming patients.

His lab also is looking at related proteins in parasitic nematodes, roundworms that cause huge losses both to crops and to livestock.

Nematicidal drugs are notoriously toxic because the parasites and their hosts share most of their biochemistry, so what kills one sickens the other. But the Jez lab might also have found targets for safer and more effective nematicidal drugs.

Not for the faint of heart

“Protein crystallography is a risky choice for a PhD project,” Lee says. “Unlike other types of experiments, it does not generate useful partial results. It’s an all-or-nothing game.“

So one of Jez’s main jobs is to be the lab’s unreasonable optimist, the one who tells the students it will be OK if a yeast gets into the lab and eats the protein in the crystallizing droplets; it will be OK if you accidentally break a $70,000 piece of analytical equipment; it will be OK if it takes another year to get a good diffraction pattern.

“It is easy to get depressed if you have a failed experiment,” Lee says. “But Dr. Jez never closes his office door. Whenever we want to talk to him, we just walk into his office. And he doesn’t criticize our mistakes. He always says ‘It’s a good learning experience!’

“As a mentor to several undergraduates, I’ve learned how hard it is to play that encouraging role.”

Practicing taking calculated risks

A climber though he fears heights, Jez climbed his way through graduate school and a postdoctoral fellowship, tackling everything from Livezey Rock to Joshua Tree. He still has the gear, he says, but these days he doesn’t have the time.

Jez cultivated optimism by climbing rocks, even though he is afraid of heights.

He started slow, climbing the side of the engineering building at Penn State University, his undergraduate alma mater, between classes.

“No one ever tried to stop climbing students,” he says. “We only went up a little bit, maybe 15 or 16 feet, and then we’d climb sideways.”

He kept at it, climbing higher and more often. He climbed his way through graduate school and a postdoctoral fellowship, often climbing three or four nights during a week and at least once on the weekend.

It’s embarrassing to explain how he gets a protein to crystallize, Jez says, because it’s more of an art than a science. Nobody really knows how to make it happen in any methodical or sensible way.

“You’re trying to coax this thing, which is big and flippy-floppy and kinda has a lot of movement,” Jez says, into becoming a crystal — a regular array of atoms.

“And you don’t really know how to do that — there’s no science to it. You start shotgunning random conditions and hope you find something that works,” he says.

Sometimes he is shotgunning several thousand different sets of growing conditions. Anxious graduate students check crystal growing trays once a day (for the first month or so, and then once a week for about 6 months) for crystals forming in droplets of protein hanging from cover slips over wells in the trays.

They need crystals — preferably nice, big ones — to stick in path of an X-ray beam at Argonne National Laboratory in Chicago.

If the crystal is a good one, and all the atoms are lined up properly, the X-rays will produce an unimpressive scattering of black spots.

The moment of truth

Embedded in that pattern, however, is the mathematical information needed to back-calculate to the position of the atoms.

A computer does the calculation, and then comes the moment of truth when a mouse click reveals whether the crystal is going to come up three cherries on the payline.

But once the mouse is clicked and a clean electron density map comes up, Jez says, “it’s like suddenly the wind has kicked up and you’re sailing free, because when you clicked that button you became the first person to ever see what that protein looks like in three dimensions.”

Lee says more simply that when he clicked the mouse: “I saw the light at the end of a five-year-long tunnel.”

A target for malaria

Lee’s payoff was an exceptionally clean electron density map for an enzyme from Plasmodium falciparum, the protozoan that causes the most lethal form of malaria.

It turns out that Plasmodium uses the enzyme to make its cell membrane.

“If you knock out this enzyme,” Jez says, “the organism can’t make more membrane, so it can’t replicate itself, and it dies.”

Malaria is notoriously hard to treat because protozoans — little animalcules with nuclei — are much closer to humans in evolutionary time than are bacteria. They share our basic metabolism, and all anti-malarial drugs that are hard on them are hard on us as well.

The enzyme that Lee crystallized — or its kissing cousin — is made by plants, by nematodes (roundworms), including both free-living and parasitic nematodes, and by Plasmodium — but not by people.

And that means, now that its structure is known, it may be possible to design a drug that would block the enzyme, kill Plasmodium, cure malaria and not be toxic to humans.

So the day Soon Goo Lee clicked the mouse button was a good day for the Jez lab.

Fast facts about Joseph Jez

Entered college intending to: Major in English and become a journalist

Bachelor’s degree: Biochemistry with an English minor from Penn State University

Doctoral degree: Biochemistry and molecular biophysics from the University of Pennsylvania

Postdoctoral work: Doing structural biology at the Salk Institute for Biological Studies in La Jolla, Calif.

Something he hasn’t mastered: Growing rock candy out of sugar water

What Jez means: “hedgehog” in Polish

A landscape-scale experiment in restoring Ozark glades (VIDEO)

Diana Lutz — 2012-01-27 00:00:00

Jon Wingo/DJM Ecological Services

Large glades, small glades and star-shaped glades that have much more “edge” in proportion to their size are all visible in this aerial shot of the Tyson Research Center, where a large-scale, long-term experiment in ecological restoration is under way.

A giant experiment is under way at the Tyson Research Center, Washington University in St. Louis’ 2,000-acre outdoor laboratory for ecosystem studies.

The experiment, led by Tiffany Knight, PhD, associate professor of biology in Arts & Sciences, will test three different variables in 32 glades with the goal of establishing best practices for restoring not just degraded glade habitats but degraded ecosystems in general.

“These glade restorations are going to be a really significant scientific resource, not just for people at Washington University but for people both nationally and internationally,” says Barbara Schaal, PhD, professor of biology and director of the Tyson Research Center.

“The opportunity to do giant manipulations and experiments is really rare, and we expect this experiment is going to draw researchers from all over the world,” Schaal says.

Missouri glades, which ecologists sometimes call sunlit islands in a forested sea, are areas of exposed bedrock in the Ozark woodlands that create their own hot, dry, desert-like microclimates and have their own unique mixture of species, including tarantulas, scorpions, and prickly pear cactus.

Before people settled the area, glades covered the Ozark mountain hilltops and oaks nestled in the valleys between ridges. When fires were suppressed after World War II, eastern red cedar — once confined to river bluffs — and rock outcrops invaded the glades, completely altering the character of these habitats and the mixture of species that lived there.

Knight’s group prepared for restoring the Tyson glades by surveying about 30 other glade restorations elsewhere in the state. “We expected smaller stored glades to have fewer species than larger glades, but we found that they had even fewer than we expected and they were also more impoverished in rare species than we expected,” Knight says.

So they decided to find out why by running the restoration of 32 glades at Tyson as a scientific experiment, complete with treatment groups and control groups.

“We’re manipulating glade shape, we’re manipulating glade size, and we’re manipulating whether or not plant species are seeded or allowed to establish on their own,” Knight says. “Those are our three big treatments, and then we’ll judge the outcome by measuring the biodiversity and composition of plants.

“Glades are biodiversity treasure chests,” Knight says. “This study focuses on a unique Ozark glade ecosystem that has been a home to many rare and endangered species found nowhere else in the world.

“Our results will have important implications for understanding and trying to mitigate biodiversity loss from small habitats, especially loss of rare species.”

On the way to the fire

In 2009, areas at the Tyson Research Center that had historically been glades were cleared by ax and chainsaw. These openings are now being maintained — as they traditionally were — by fire.

The prescribed burns began the week of Jan. 9, 2012. With weather conditions perfect, the glades were being burned, at the rate of about two a day. Knight picked up the videographer and reporter at the research center to drive them to the fire site. (See movie below).

http://youtu.be/N01BygHu-T0Tiffany Knight explains the glade restoration experiment on the day of a prescribed burn.
“Usually there are several clues that an area was a glade,” Knight said over the rumble of the pickup. “When you’re driving along, you’ll see big boulders and rocks right on the surface of the soil. What that tells us is the soil is really shallow, which is characteristic of a glade habitat.

“Another thing you’ll notice, especially in aerial photographs taken in winter, is eastern red cedar. The southwestern corner of the Tyson Research Center is covered with it. Eastern red cedar is the first plant to encroach on glades in the absence of fire. If fire is suppressed, eastern red cedar comes in, gets established, and allows the glade habitat to succeed into a forest.

“Another telltale sign is plants that are remnants of glades. I’d be walking through the forest doing other research,” Knight says, “and I would notice plant species like cactus in the middle of the forest. It was clearly a species just trying to hang on, waiting for the day when the habitat became a glade again.

“All of these are good indicators that an area was a glade historically,” she says.

By now we had arrived at the next glade to be burned, a big, round glade with a southern exposure that had been strewn with the seeds of glade-favoring species.

At the fire

“Fire travels uphill,” Knight says as we get out of the pickup, “so they burn the top of the hill first — a small, low-intensity burn — so that when they light the bottom and the fire moves up, there’s no way for it to ignite the slash (piles of timber and brush) left over from glade clearing.”

The crews are motley: half pros, half students. One of the teams is led by John Timmerman, a retired firefighter who now does prescribed burns. Another is led by John Wingo, a contractor whose business is ecological restoration. They wield the drip torches and leaf blowers (used to extinguish small flames).

Even though it’s winter break students are scraping out the fire break around the glade and are raking embers back into burning piles of vegetation.

“The research involves scientists at all levels: faculty, postdoctoral associates, graduate students, undergraduates and high school interns,” Knight says.

“My only job at these fires,” Knight says, “is to look outside the fire circle and make sure flying sparks haven’t set anything alight.

“This glade was seeded,” Knight says, walking by the flaming stalks of wooly mullein, “by a striking plant that is adapted to live in disturbed landscapes, but will eventually be outcompeted by returning glade species.

“We put in 50 species, and we went to extra effort to get some of the rarest species in there, some that are listed by the state or federal government as threatened and others that grow only in glade ecosystems.”

Holly Bernardo, who has a master’s degree in ecology and is a technician on the project, explains how they got the seeds. “There are some local seed houses,” Bernardo says, “and — their words, not mine — they have a bunch of old hippies they send out to collect seeds for them. We tell them what we want, and they go find it and take care of all the permitting for us.

“Six or seven species we collected ourselves from the Missouri Botanical Garden’s Shaw Nature Reserve because there are so many nice populations on its restored glades.

“The seed houses are pretty good for the normal stuff, general glade species that also grow in prairies and other habitats,” Bernardo says. “Those are easy to get.”

Tephrosia from Wikimedia Commons; all others from Missouri Botanical Garden

Plants seeded in the glades include, clockwise from top left: Rudbeckia missouriensis, Dalea purpurea, Baptisia austalis and Tephrosia virginiana.

Among the seeded species are Tephrosia virginiana, or goat’s rue; Dalea purpurea, called purple prairie clover; Rudbeckia missouriensis, the poster child for Missouri glades; Opuntia humifusa, the prickly pear cactus; and Baptisia australis, or blue indigo.

Afterglow

By now the glade has been reduced to patchy white ash and the crew is regrouping to move to the next glade to be burned.

The glades will be burned next year, and the year after that. There will be more ash next year, says Knight, when there is more plant biomass available to burn.

The National Science Foundation has funded the restoration experiment for five years, says Knight, the standard grant period. But this is really a 20- to 30-year experiment that will spawn other questions and smaller experiments to answer those questions.

“The Opuntia pads we put in this summer took really well,” Bernardo says. “They grow really slowly, but we’ll have some nice Opuntia populations in 20 years.”

Knight is in it for the long haul. She plans to monitor plant communities in the glade ecosystems for decades, following several rare species. Additional experiments will test the importance of plant and animal interactions on biodiversity, such as the impact of mammal and insect predation.

Although the plants are the stars of this show, Knight already has initiated collaborations with other scientists to keep an eye on the animals — at least the small ones.

James Trager, PhD, of the Missouri Botanical Garden, is monitoring the recovery of ant populations, and Mike Arduser, a bee specialist with the Missouri Department of Conservation, is interested in how long it will take for glade-endemic bees to return.

“This is stunning work,” Schaal says. “Not only do we have the expanse of Tyson to experiment with, the design of the project is just simply clever, and we have the intellectual resources to really follow the research.

“It’s a huge, clever project and I’m really excited about it,” Schaal says.

Visual nudge improves accuracy of mammogram readings

Diana Lutz — 2012-01-26 00:00:00

In 2011 — to the consternation of women everywhere — a systematic review of randomized clinical trials showed that routine mammography was of little value to younger women at average or low risk of breast cancer.

The review showed, for example, that for every 50-year-old woman whose life is prolonged by mammography, dozens are treated unnecessarily — some with harmful consequences — or treated without benefit. Hundreds are told they have breast cancer when they do not.

Cindy M. Grimm, PhD, associate professor of computer science and engineering in the School of Engineering & Applied Science at Washington University in St. Louis, was not surprised by the review, a prestigious Cochrane review of the scientific evidence for a medical treatment.

“It’s not just the mammogram that’s the problem,” she says, “it’s accurately interpreting the mammogram.

“People aren’t good at it. Even expert radiologists aren’t good at it. Results vary widely from person to person, even when people have gone through the same training.”

But Grimm thought a perceptual trick she and colleagues had invented, called subtle gaze direction, might be used to improve training.

An experiment showed that a novice could be subtly guided to follow an expert’s scanpath across a mammogram and that this subtle nudging improved the novice’s accuracy.

The experimental results will be presented at the Eye Tracking Research & Application Symposium this March.

Grimm and her colleagues say the technique, should it prove durable, is widely applicable to visual search tasks. Not only might it improve the reading of mammograms and other types of medical images, such as MRIs and PET scans, but it might also be used to improve the accuracy of airport screening and learning in virtual environments.

Directing the gaze

Wikigallery.org

In this painting of a Jewish Quarter by the 19th-century Dutch painter Salomon Leonardus Verveer, the people in the center of the image are brighter than they would be in a snapshot, which draws your eye toward them. The walls of the buildings focus your attention toward the middle of the image as well. WUSTL computer scientist Cindy Grimm says similar tricks can be used to help people learn difficult visual search tasks, such as scanning mammograms for tumors.

Grimm invented subtle gaze direction together with colleagues Reynold Bailey, PhD, then her graduate student, and Ann McNamara, PhD, then of Saint Louis University, a conference acquaintance.

“I had double-majored in art and computer science as an undergraduate at the University of California, Berkeley,” Grimm says. “So I was aware that artists have all sorts of tricks for guiding viewers to look at particular areas in a painting, sometimes, in the case of narrative art, in a particular sequence.

“They might make an area brighter than the background, increase the contrast or have strong edges (borders) that attract the eye.

“Movie producers do the same thing in post processing,” Grimm says. “For example, when one actor is talking and others are listening, the audience tends to watch the talker. But the producer can direct attention to a listener’s reaction instead by changing the color or brightness of that part of the image.”

Subtle gaze direction is a high-tech version of this time-honored craft. It works, says Grimm, by exploiting the difference between peripheral and central (foveal) vision.

“We use a small area in the central part of our retina called the fovea to see detail,” she says. “But foveal vision doesn’t actually cover much of our field of view.

“If you hold out your thumb, your foveal vision — the part of your surroundings you’re actually seeing in detail — covers about the same area as your thumbnail.

“We use our foveal vision to read or drive or for other detail-oriented tasks. At the same time, we are monitoring the rest of our environment with our peripheral vision, which has lower resolution but responds faster than our foveal vision.

“When our peripheral vision picks up a stimulus, our eyes move to focus our foveal vision on it so that we can see it clearly.

“During those quick eye movements, called saccades, vision is suppressed, or masked, so that the motion of the eye, the motion blur of the image and the gap in visual perception are not noticeable to the viewer. We lose an astonishing 40 minutes of vision a day to saccadic masking.”

Grimm, Bailey et al.

In subtle gaze direction, the modulation of the brightness (middle column) or warmth (third column) of a part of the image in the peripheral field of view is used to attract the viewer’s focus to that area. By moving the stimulus the viewer can be coaxed into scanning the image in a particular pattern. The stimulus is cut off before the viewer can focus on it and so the gaze direction remains subtle.

To direct the gaze, Grimm and her colleagues changed the brightness or “warmth” of an area in the peripheral field of view to draw the novice’s focus to this area.

The stimulus remained subtle, however, because the viewer’s gaze is monitored in real-time by an eye-tracking device and the modulations to the peripheral vision are terminated before the eye fixates on them.

“The idea,” says Grimm “is to get someone to look in a particular direction while altering their experience of viewing the image as little as possible.”

“In the case of mammograms,” for example, “you want to get a learner to look at the tumor region but you don’t want to do anything that makes the tumor region look different than it does on the mammogram itself.”

The mammography study

Reading mammograms is a good target for computer assistance because training is time-consuming and expensive, typically requiring a four-year residency and a two-year fellowship.

Despite advances in technology, novices are still trained by working as an apprentice to an expert.

The mammography study, led by Bailey, now an assistant professor of computer science at the Rochester Institute of Technology, brought together the same group of scientists as the subtle gaze direction experiment. McNamara is now assistant professor of visualization at Texas A&M University.

For the study, Grimm and her colleagues used a database of images provided by the Mammographic Image Analysis Society that includes both images and text files that contains coordinates of abnormalities and their size.

“Expert diagnostic radiologists have a particular search pattern that is not the same as that of a novice,” Grimm says. “We don’t know exactly what they’re doing, but they tend to do a fairly broad scan and then fixate on parts of the image that have a tumor-like texture. A novice might instead attend to brighter spots in the image or fail to scan all of it.”

Bailey hired an expert radiologist at the Rochester Institute of Technology to view and mark 65 images from the database. The expert’s scanpath was recorded during this process by an eye-tracking system.

During the experiment, subtle gaze direction was used to guide a group of novices along the expert scanpath. A control group viewed the mammograms without gaze manipulation.

In the study, gaze direction was used to nudge novices into following an expert radiologist’s scanpath (a simplified version of which is shown in green) as they looked at a mammogram. A potential tumor is circled in red.

Novices who were guided were significantly more accurate than the control group or a third group guided along a random path. Moreover, even though the training session was brief, the effect lingered even after gaze manipulation was disabled.

To watch a Power Point of the experimental results, click here.

Grimm says more work must be done to show that more extensive training will stick long-term. In the meantime, she can think of many ways gaze manipulation could be used to improve performance on visual search tasks.

“One simple use of the technology would be to make sure readers look at every part of the image. If you’re using eye tracking,” she says, “you know where people are looking, so you can make sure they don’t skip part of the image.”

Gaze manipulation might also be used to assist tumor-recognition software. “Suppose you had a software program that was reasonably good at spotting possible tumor areas but, erring on the side of caution, flagged too many areas as suspicious.

“Such software might be paired with gaze direction to ensure the radiologist looked at all of the flagged areas,” she says. “That wouldn’t necessarily be a training application; it could be a routine element of reading mammograms.”

The mammogram study is widely applicable, Grimm says, because there are so many visual search tasks. She mentions airport scanners, but they are just at the top of a long list.

“I work with someone who identifies pollen species,” she says. “Apparently, it takes a novice a year to learn, and they spend hours and hours looking through a microscope at these pollen grains. Again, some people are good at it and others struggle for competence.

“Perhaps in that case, as well, gaze direction could be used to train novice pollen identifiers.”

Hands-on astronomy

2012-01-25 00:00:00

The logo for the WUSTL Laboratory for Space Sciences combines a microscope and a telescope. Lab member Tom Bernatowicz, PhD, likes to quote Victor Hugo on the topic: “Where the telescope ends, the microscope begins. Which of the two has the grander view?”

A workshop that gathers scientists who study tiny bits of stars that were born and died billions of years ago — before the formation of the solar system — is returning to Washington University in St. Louis this year.

The Presolar Grain Workshop is part of a series that was started in 1990 by Donald Clayton, PhD, a physicist and astronomer at Clemson University. Most workshops have been held at Clemson and Washington Univerity, but, in the past five years, two were held at the University of Chicago and the Carnegie Institution.

Sessions begin at 8:30 a.m. Saturday, Jan. 28, and continue through the weekend in Crow and Compton halls.

Attendees will include 45 astrophysicists from WUSTL’s Laboratory for Space Sciences and other research institutions in the United States as well as from Australia, Brazil and Italy.

The Laboratory for Space Sciences is part of the departments of Physics and of Earth and Planetary Sciences, both in Arts & Sciences, and the McDonnell Center for the Space Sciences.

The presolar grain community likes to call its field of study “science with a microscope rather than a telescope.” It is the only area of astrophysics where scientists can get their hands on the material they are studying and subject it to analysis in the laboratory.

Created in the outflows of red giants and in the bellies of supernovas before they exploded, the mineral grains got caught up in the molecular cloud out of which the Sun and planets formed and then were swept up into asteroids, pieces of which later fell to Earth as meteorites.

The small fraction of the grains that made the extraordinary voyage unaltered provide invaluable clues to the ancient stars, where they were made, and the history and origins of the solar system.

Because the scientists can examine stardust in their laboratories, presolar grain workshops are characterized by unusual scientific interchange between experiment and theory that often sparks new ideas. The program for the upcoming meeting characteristically alternates experiment and theory, isotopic compositions of stardust and models of nuclear processes taking place in stars.

Sponsored by the McDonnell Center for the Space Sciences, the workshop is hosted by Ernst Zinner, PhD, research professor of physics and of earth and planetary sciences.

New Mars rover's mechanics to be used to study Martian soil properties

Diana Lutz — 2012-01-19 00:00:00

NASA/JPL-Caltech

The Curiosity rover, which lifted off Nov. 26, 2011, will arrive at the Red Planet in August 2012. The rover, shown here during testing inside the Spacecraft Assembly Facility at the Jet Propulsion Laboratory in California, is about the size of a Mini Cooper and weighs roughly five times as much as the Spirit and Opportunity rovers.

NASA has announced that Raymond E. Arvidson, PhD, the James S. McDonnell Distinguished University Professor in Earth and Planetary Sciences in Arts & Sciences at Washington University in St. Louis, has been selected to be a participating scientist on the Mars Science Laboratory, a mission to land and operate a rover named Curiosity on the surface of Mars.

Arvidson proposed to NASA that he use the rover itself as a terramechanics instrument to learn about Martian soils. Terramechanics is the study of soil properties, especially those revealed by driving a vehicle over different terrains.

His proposal was one of 29 selected from among 149 vying for a coveted participating scientist spot on the rover team.

His co-investigator will be Karl Iagnemma, PhD, a principal research scientist at the Massachusetts Institute of Technology (MIT) and a terramechanics expert.

Arvidson says the project has both operational and scientific purposes.

The operational purpose is to help Curiosity chart the best path across the Martian terrain, avoiding sand traps and slippery slopes, and the scientific purpose is to study crusted soils.

Crusted soils are of interest both because rovers can break through the crusts and become mired in the softer soils they conceal, but also because they are created by the meager modern remains of the Martian water cycle, which is of considerable interest because water is a key ingredient of potentially habitable environments.

The biggest and the baddest of the rovers

Arvidson has been a faithful attendant to the twin Spirit and Opportunity rovers since they landed on opposite sides of Mars in January 2004. They completed their primary missions in three months and went into overtime work in April 2004.

Spirit broke through a crusted soil at an area called “Columbia Hills” in April 2009 and became mired in the underlying soils. Because its solar panels were tilted in an unfavorable direction, it eventually lost power and stopped communicating. The Spirit mission was officially declared over in May 2011.

Opportunity, however, continues to roam Mars and is now exploring the rim of an ancient crater called Endeavour, where it has just made some interesting finds.

Joe Angeles/WUSTL

Arvidson has been deeply involved in Mars missions for more than 30 years, serving as the Viking lander imaging team leader, the Phoenix robotic arm co-investigator and the deputy principal investigator for Spirit and Opportunity. This photo was taken when he was leading the group selecting a landing site for the Phoenix lander, which eventually grabbed a chunk of ice from the high northern latitudes of Mars.

Currently in transit to Mars, Curiosity, which lifted off Nov. 26, 2011, is scheduled to land on Aug. 6 of this year. Five times larger than Spirit or Opportunity, it carries much more sophisticated analytical equipment.

Whereas Spirit and Opportunity were powered by the sun, Curiosity is powered by plutonium and can operate night and day. Its expected lifetime is also much longer: 23 Earth months (one Martian year). Unlike its predecessors, its mission is not only to search Mars for water, but also to investigate other evidence of potentially habitable environments.

Simulating Martian terramechanics

Arvidson’s team will scout out territory for Curiosity using a dynamic computer model of the rover that can simulate Curiosity driving over Martian topography and soils.

The model will be similar to Artemis, a three-dimensional dynamic model originally developed jointly by Arvidson and colleagues at Washington University and the Jet Propulsion Laboratory (JPL) to try to help the Spirit rover get out of the sand trap in which it became mired in spring 2009.

http://youtu.be/hcd3KODTod8?hd=1Artemis at work the weekend of Dec. 17-18

Artemis is now being used to chart the best path for the Opportunity rover to take on and around the rim of the crater Endeavour. Over the weekend of Dec. 17-18, Opportunity automatically stopped a commanded drive on a rock outcrop because the right front wheel motor current (dashed blue trace in movie, above) exceeded a preset limit. The Artemis simulation showed that the right wheel current was high because that wheel was trying to do all the work of moving the vehicle, and that the rover could be extricated from its situation simply by backing it up.

“When we drive the rover,” Arvidson says, “we make a topographic map of the surface using data both from orbital instruments and from the rover’s cameras. Every two seconds we also record the rover’s yaw, pitch and roll, and motor currents, and we evaluate how much the wheels are sinking and how much the vehicle is drifting or slipping.

“For the simulations, we shrink a topographic map to the appropriate scale, drop the simulated rover on it, and drive it using a series of commands just as engineers drive the rovers on Mars.

“Each spot on the topographic model is associated with a particular type of bedrock or of soil that has a certain stickiness or looseness — and perhaps a crust.

“We work with our colleagues at MIT and JPL to calibrate the soil parameters,” Arvidson says. “The MIT lab has an instrumented Opportunity spare wheel — a flight wheel that we didn’t send to Mars — and they’re running it back and forth through soils to better establish the link between rover dynamics and soil types.

“Once the rover simulation model for Curiosity has been developed, it will be validated by driving a full-scale engineering model of the rover around the Mars Yard, a mocked-up Martian landscape at the Jet Propulsion Laboratory. The engineering model is about a third the weight of the flight model because gravity on Earth is three times stronger than on Mars.

“When Curiosity lands on Mars,” Arvidson says, “we’ll drive our computer model on the same traverses as Curiosity and adjust the soil properties in the simulation until we get a good match with Curiosity’s dynamics. Then we’ll know what we’re up against.

“In that way, we can contribute to path planning for the Curiosity rover,” Arvidson says.

Crusted soils

Arvidson was alerted to the dangers — but also the scientific interest — of crusted soils by an episode in April 2009, when the Spirit rover was commanded to drive backward through a valley at a location now known as Troy.

The terrain looked innocuous enough, but the rover’s wheels broke through a surface crust and became embedded in underlying sand at what turned out to be the inner wall of an eight-meter-wide sand-filled crater.

Frustrating as this was, the rover team was intrigued when the floundering rover revealed much lighter soils beneath the dark crust.

NASA/JPL/Cornell

An image from the panoramic camera on the Spirit rover shows the terrain around Troy, where Spirit became embedded in soft soil during the spring of 2009. When the rover’s wheels cut through the darker top layer of soil, much lighter soils (white smear toward the bottom of the image) were revealed. Investigation showed that the soils had been sorted according to their solubility in water, evidence that a water cycle persists on Mars to this day.

Tools on Spirit’s robotic arm were used to examine the composition of the different layers of the soil closely.

It turned out that the reddish crust consisted of minerals such as hematite that are less soluble in water than the relatively soluble ferric sulfate sands beneath them.

This soil profile was consistent with water slowly moving dissolved material down the soil column.

“It wouldn’t take much water to sort minerals in this way,” Arvidson says. Even skimpy processes, such as partial melting of dirty snow when the Martian poles are tipped toward the Sun, might be enough to do it.

As the simulated Curiosity rover refines its knowledge of crusted soils, Arvidson hopes to use CRISM, a multispectral imager aboard the Mars Reconnaissance Orbiter, to find other patches of these crusted soils.

“If we can identify where they are, we can drive the rover to them, ‘toe dip’ into them and expose the subsurface,” he says.

Curiosity will then be able to use its armamentarium of analytical equipment to analyze the soils.

“What we’ll be doing is characterizing the Mars water cycle,” Arvidson says.

Active lifestyle associated with less Alzheimer disease-related brain change among persons with APOE ε4 genotype

2012-01-16 00:00:00

A sedentary lifestyle is associated with greater cerebral amyloid deposition, which is characteristic of Alzheimer's disease (AD), among cognitively normal individuals with the ε4 allele of the apolipoprotein E (APOE) gene, according to a report published Online First by Archives of Neurology, one of the JAMA/Archives journals.

"The presence of an APOE ε4 allele is the most established genetic risk factor for Alzheimer disease (AD), with a higher percentage of individuals with AD having an ε4 allele in comparison with the general population," the authors write as background information in the article. "It has been suggested that APOE status may modify associations between lifestyle factors such as exercise engagement and risk of cognitive decline and dementia."

To examine the association between exercise and cerebral amyloid deposition among patients with and without the APOE ε4 allele, Denise Head, Ph.D., and colleagues from Washington University in St. Louis, performed APOE genotyping and administered a questionnaire on physical exercise engagement over the last decade to 201 cognitively normal adults (135 women) age 45 to 88 years recruited from the Knight Alzheimer's Disease Research Center. Samples of cerebrospinal fluid were collected from 165 participants and brain amyloid imaging with positron emission tomography (PET) of the amyloid binding agent carbon 11-labeled Pittsburgh Compound B (PiB) was performed on 163 patients.

Patients who reported higher amounts of exercise had a lower mean (average) cortical PIB binding (binding potential values from the prefrontal cortex, gyrus rectus, lateral temporal, and precuneus regions) than did patients who reported lower amounts of exercise. Participants who were ε4-positive also had higher levels of cortical amyloid compared with individuals negative for the ε4 allele. The authors also observed a "novel interaction between APOE status and exercise engagement for [11C] PiB binding [carbon 11-labeled Pittsburgh Compound B] such that a more sedentary lifestyle was significantly associated with higher [11C] PiB binding for ε4 carriers but not for noncarriers. All findings remain significant after controlling for age; sex; educational level; body mass index; the presence or history of hypertension; diabetes mellitus; heart problems, or depression; and the interval between assessments."

According to past research "APOE status is associated with increased risk of cognitive decline and elevated amyloid deposition. In contrast, exercise engagement has been associated with reduced risk of cognitive decline and lower levels of amyloid deposition," the authors note. "In summary, our findings suggest that exercise at levels recommended by the AHA [American Heart Association] may be particularly beneficial in reducing the risk of brain amyloid deposition in cognitively normal ε4-positive individuals."

Editor's Note: To contact Denise Head, Ph.D., call Gerry Everding at 314-935-6375 or e-mail gerry_everding@wustl.edu. For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations@jama-archives.org.

Global climate change: Ralph Cicerone joins WUSTL conversation

2012-01-12 00:00:00

Brian Wilson

Ralph J. Cicerone, president of the National Academy of Sciences, delivering the Princeton Environmental Institute’s 2011 Taplin Environmental Lecture.

Ralph J. Cicerone, PhD, president of the National Academy of Sciences and chair of the National Research Council, will present a seminar on climate change at Washington University in St. Louis at 4 p.m. Monday, Jan. 23, in Room 300, Laboratory Sciences Building on the Danforth Campus.

Chancellor Mark S. Wrighton will introduce him.

The seminar, "Global Climate Change and Demand for Energy," is part of a conversation about climate change that began last October when a small group of faculty gathered in the new International Center for Advanced Renewable Energy and Sustainability (I-CARES) conference room in Green Hall to brainstorm ways to put the entire weight of the WUSTL community behind efforts to address climate change.

"Contemporary climate change is seen in measured temperatures of air and oceans, ice losses from the Greenland and Antarctic continents and the Arctic sea, and sea-level rise." Cicerone says.

"Increased concentrations of greenhouse gases in the global atmosphere from human activities, principally fossil-fuel burning, are the likely cause of these changes. Earth's carbon cycle is out of balance, with more carbon dioxide entering the atmosphere each year than can be absorbed by oceans and land so that future climatic changes may be much larger.

"The challenge of meeting energy demand without causing dangerous climate change is joining two other strategic goals for energy: access to domestically secure and low-cost sources," he says.

The seminar is co-sponsored by the Tyson Research Center and I-CARES. It is free and open to the public.

The seminar is part of a larger conversation about climate change that is being led by Barbara Schaal, PhD, the Mary-Dell Chilton Distinguished Professor in the Department of Biology in Arts & Sciences, vice president of the National Academy of Sciences and director of the Tyson Research Center, and coordinated by Himadri Pakrasi, PhD, the George William and Irene Koechig Freiberg Professor of Biology in Arts & Sciences, professor of energy in the School of Engineering & Applied Science, and director of I-CARES.

Cicerone’s research in atmospheric chemistry, climate change and energy has involved him in shaping science and environmental policy at the highest levels nationally and internationally.

He has taken a leading role in the writing of the National Research Council series of reports “America’s Climate Choices.” These are authoritative analyses produced at the request of Congress to inform and guide responses to climate change across the nation.

The series includes four focused panel reports and an overarching report. The panel reports are: Advancing the Science of Climate Change; Limiting the Magnitude of Climate Change; Adapting to the Impacts of Climate Change; and Informing an Effective Response to Climate Change.

The overarching report is America’s Climate Choices: Final Report. All of the reports can be ordered from the National Academy of Sciences site: http://nas-sites.org/americasclimatechoices/sample-page/

“Its a great opportunity to hear one the nation’s leading scientists who was involved in the research on the topic and now leads a lot of the response to climate change, “ Schaal says.

An ongoing conversation

Schaal has long felt that the climate debate has not been moving forward fast enough.

As she points out, global warming has been a topic of concern since the late 1950s, when scientist Charles D. Keeling’s measurements at the Mauna Loa Observatory in Hawaii first alerted the world to the progressive buildup of carbon dioxide in the atmosphere.

When Schaal took over as director of the Tyson Research Center last summer, she felt she had been handed a golden opportunity to act on her concerns. At the research center, which includes 2,000 acres of woods, prairie, ponds and savannas located some 20 miles southwest of the Danforth Campus, dozens of WUSTL faculty study ecology, biodiversity and restoration management.

Schaal quickly discovered that Pakrasi was thinking on parallel lines as he sought to find ways to engage the entire university community in issues central to the I-CARES mission.

I-CARES was founded in 2007 to foster institutional, regional, and international research on biofuels from plant and microbial systems, sustainable alternative energy and the exploration of environmental systems and practices.

Under the I-CARES umbrella are the Tyson Research Center and the Photosynthetic Antenna Research Center (PARC).

“When I started thinking about climate change, it became absolutely clear in my mind that the entire institution should be involved, and we don’t have anything going on that is focused that broadly,” Pakrasi says.

By design, the initial group that met in October to brainstorm was small and comprised people from disparate disciplines. “We have anthropologists, we have engineers, we have artists, we have social scientists,” Schaal says. “The broader the better. That’s where you’re going to get the real synergies — among all the disciplines, not just science.”

The climate change conversation is one of three I-CARES conversations Pakrasi hopes to start this year.

A second conversation, “Building for the Future of Our Cities,” led by Christof Jantzen, the I-CARES Professor of Practice in the School of Architecture in the Sam Fox School of Design & Visual Arts, and Bruce Lindsey, the E. Desmond Lee Professor for Community Collaboration and dean of the College of Architecture and Graduate School of Architecture & Urban Design, is getting underway this month.

What might come of a conversation

One purpose of the conversation, Schaal says, is to lift the pall of apathy that seems to have fallen over the topic of climate change.

“It’s so easy for people just to give up, and we can’t do that,” Schaal says. “Tyson gave me an opportunity to say, ‘let’s talk about climate change at this university, not just in science but across a lot of different fields, and see what we can do.’

“Let’s see if we can get graduate students interested — I know the undergraduates are tremendously interested. There are many things that can be done,” Schaal says.

“One of the problems with universities,” Schaal says, “is that it’s really hard to learn what other people are studying. But once you know what somebody else is doing, you can see really wonderful areas of overlap where there could be collaborations. So one purpose of the conversation is to locate the synergies among faculty,” she says.

Pakrasi says he regards the I-CARES conversations as similar to start-up companies; they will live or die by their success in engaging the university community.

“It’s up to them,” Pakrasi says. “They need to feel that this is important enough that they will do all that needs to be done.”

But both Schaal and Pakrasi are deeply committed to the climate change conversation.

“I view climate change as a tremendous challenge,” Schaal says. “Something that is going to be with us for a long time, something that I think our undergraduate students need to be aware of and educated about, and something that a responsible university needs to address.”

Pakrasi needs no convincing. His family was displaced to India from Bangladesh, widely recognized as one of the countries most vulnerable to climate change, and already suffering increased rainfall, rising sea levels and ferocious tropical cyclones.

“Another foot of water will take 80 percent of that country below water,” he says. “It’s beyond getting worried, we need to prepare for the changes that are coming.”

Pakrasi remains optimistic. “The hope is always with the young people,” he says, “because it’s their future that’s at stake.”

For a video of Barbara Schaal introducing Ralph Cicerone’s talk “Climate Change Seen from Space and Earth’s Surface,” visit http://www.youtube.com/watch?v=6jd5A_FLOtc

MD-PhD student starts nanotechnology company

Caroline Arbanas — 2012-01-11 00:00:00

Joe Angeles

Washington University MD-PhD student Matthew MacEwan recently started his own nanotechnology company, NanoMed LLC, which is developing a synthetic polymer surgical mesh made of individual strands of nanofibers.

Matthew MacEwan is no ordinary medical student.

The neurosurgeon-to-be, a student at Washington University School of Medicine in St. Louis, also is pursuing a doctorate in biomedical engineering. And at 29, he recently started his own company, NanoMed LLC, aimed at revolutionizing the surgical mesh used in operating rooms worldwide.

The lead product, invented by MacEwan and Jingwei Xie, PhD, a former postdoctoral researcher in engineering, is a synthetic polymer mesh made of individual strands of nanofibers. The mesh was developed to repair injuries to the brain and spinal cord but could also be used to mend hernias, fistulas or other injuries.

The nanofiber material has the potential to make operations easier for surgeons to perform. For patients, the mesh could lead to fewer complications after surgery because it naturally breaks down over time.

Existing surgical mesh used to repair the protective membrane that covers the brain and spinal cord is thick and stiff, making it difficult to work with. But the novel material MacEwan and Xie developed is thin and flexible and more likely to integrate with the body’s own tissues.

“It’s almost like a cloth,” MacEwan says. “But it’s designed on a nanoscopic scale. To put that into perspective, every thread of the mesh is thousands of times smaller than the diameter of a single cell.”

The technology’s promise has caught the attention of the business world. In 2011, MacEwan won the prestigious Olin Cup, sponsored by Washington University’s Skandalaris Center for Entrepreneurial Studies. The business plan competition recognizes startups with a high probability of success.

Then in June, he won the Licensing Executives Society Foundation’s International Graduate Student competition in London, and in November, the Idea to Product Global Competition in Stockholm. The winnings of more than $100,000, along with other investments and in-kind services, have helped MacEwan get the company off the ground.

“It’s incredibly exciting to see a product we developed make its way to the commercial market,” MacEwan says.

The nanofiber material was developed in Washington University laboratories by MacEwan and Xie, now a senior scientist at Marshall University in West Virginia, along with collaborators Younan Xia, PhD, the James M. McKelvey Professor of Biomedical Engineering, and Zack Ray, MD, now a neurosurgical fellow at the University of Utah. MacEwan has worked closely with the university’s Office of Technology Management, which has filed patents on the technology.

Courtesy image

Fibroblasts (in bright blue), the cells that cover the surfaces of the intestine and other organs, grow along nanofabricated surgical mesh designed in a starburst pattern. The individual nanofibers originate from a central point and radiate outward, encouraging cells to migrate and grow toward the center for a wound.

Currently, many surgical meshes are derived from pig or cow skin. These tissues must be chemically treated and processed so that they can be left in the body. As a result, the meshes can be rigid and bulky, and difficult to shape to the convoluted surface of the human brain.

In contrast, the nanofiber material MacEwan developed is organized on a size scale familiar to cells and replicates their natural environment.

“We’ve taken the whole idea of surgical mesh and pushed it into a new direction,” MacEwan says. “It’s not just a foreign material you’re putting into the body. The nanofabricated nature of the mesh creates a scaffold that cells can easily penetrate and populate to recapitulate the body’s tissues.”

The surgical mesh looks like gauze but feels sticky, like a spider web. It is typically composed of multiple layers of nanofibers and can be cut to size for different uses. Once the mesh is placed in the body, cells grow along the individual nanofibers, which gradually degrade in nine to 12 months, leaving the body’s own tissue in its place.

One advantage of the new technology is that different patterns of nanofibers can be created in the mesh to promote the healing of different kinds of wounds. For example, in a starburst pattern used to repair ulcers and other circular wounds, the nanofibers originate from a central point and radiate outward. This encourages cells to migrate and grow toward the center of the wound.

For linear defects like tears and incisions, nanofibers can be aligned perpendicular to the wound, encouraging cell growth across the injury, which provides reinforcement to the new tissues.

“We can really manipulate and change the design of the material to optimize it for specific clinical uses and applications,” MacEwan says.

MacEwan is now evaluating the product in animal models, a first step toward gaining U.S. Food and Drug Administration approval. Preliminary studies indicate the nanofiber material is safe and effective. MacEwan is hopeful that clinical trials in patients will begin later this year.

NanoMed LLC is based in St. Louis. In November, Agnes Rey-Giraud, a former executive and board member at Express Scripts, joined the company to head business development.

For now, MacEwan is finishing his doctorate and has two years left before he receives his medical degree. He’s planning a career in academic medicine, where he can spend time in the laboratory and the operating room. There, he hopes to use the nanofiber surgical meshes he developed to improve the care and surgical outcomes of his own patients.

“At Washington University, I have continually focused on moving discoveries beyond the laboratory,” MacEwan says. “I hope to see this technology have a positive impact on many patients. Nothing would be more thrilling to me.”

Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Krawczynski group receives NASA grant to spy on black holes

Diana Lutz — 2012-01-06 00:00:00

ESA. Illustration by Martin Kornmesser, ESA/ECF

Artist’s view of the binary system Cygnus X-1 that will be one of the targets for the X-ray polarization instrument X-Calibur, scheduled to be in the air in fall 2013 or spring 2014. The image shows how matter from a companion star (left) heats up as it is drawn into a spiraling disk of material around a black hole with a mass of about 15 Suns (right).

Henric Krawczynski, PhD, professor of physics in Arts & Sciences at Washington University in St. Louis, is a big-game hunter of the astrophysical variety — he hunts celestial beasts, not beasts of the forest. The more exotic and wilier the prey, the keener he becomes, and the more his eyes light up.

The National Aeronautics and Space Administration (NASA) has just funded Krawczynski and his colleague, assistant research professor Matthias Beilicke, PhD, to chase some of the most exotic astronomical prey: black holes, those famously elusive quarry that cleverly swallow most of the evidence of their existence.

He will be doing it with an instrument Jules Verne would appreciate, a balloon-borne telescope sensitive to the polarization of light that will float at an altitude of 130,000 feet for a day. During that time, the balloon will stare fixedly at two black holes in our galaxy, an extragalactic black hole, an accreting neutron star, the Crab nebula, and other targets yet to be chosen.

Called X-Calibur, the instrument, which is sensitive to “hard” X-rays with energies between 20,000 and 60,000 electron volts, is scheduled to go up in the spring 2013 or fall 2014. It will be flown at roughly the same time as another mission, GEMS, a satellite-borne instrument sensitive to “soft” X-rays, with energies between 2,000 and 10,000 electron volts. For comparison, visible light has energies between 2 and 3 electrons volts.

Krawczynski leads the X-Calibur experiment, whose development was sponsored by the McDonnell Center for the Space Sciences at Washington University. Krawczynski is a science collaborator on the GEMS experiment, which is led by Jean Swank, PhD, of the Goddard Space Flight Center.

To date, astronomers have measured X-ray polarization from only one astronomical source outside the solar system, the Crab Nebula, a supernova remnant in the constellation Taurus. GEMS is two orders of magnitude more sensitive than the instrument that looked at the Crab. X-Calibur extends the energy coverage into the hard X-ray regime, Krawczynski says.

Like polarized sunglasses only better

Optical Image: Kitt Peak National Observatory. X-ray image: ROSAT/MPE/S. L. Snowden

Two images of the Coma cluster demonstrate how different celestial objects can look at different wavelengths. The optical image (left) reveals roughly 3,000 galaxies, each of which contains billions of stars. The X-ray images (right) show a blob of hot gas ejected from stars in the galaxies over a period of about a billion years, some of it at a blistering temperature of 100,000,000 degrees Celsius. The gas has five to 10 times the mass of the galaxies.

“Whenever you look at the sky at a different wavelength,” Krawczynski says, “you see something completely different.”

So, astrophysicists, ever hungry for new insights, have launched a fleet of telescopes that cover most of the electromagnetic spectrum, from the lazy infrared to the jazzed-up gamma rays.

“We are in a golden age of astrophysics,” Krawczynski says, “because we have great observatories. But it has also become more difficult to make the case for a new scientific tool. We need a technological breakthrough or new observables,” he says.

X-Calibur offers a little of both, but its main claim to fame are two new observables: the polarization degree and direction of X-rays, which provide information about cosmic sources that is not available in any other way.

Electromagnetic waves (light, inclu) are composed of electric and magnetic waves that vibrate at right angles to one another and to the direction of travel of the light wave. When light is unpolarized, the direction of vibration of the electric or magnetic wave is random. When the light is polarized, the waves vibrate in a particular direction.

Light can be polarized by various processes, including reflection and passing through certain materials.

Most everyone has limited experience with polarization in the form of glare-free sunglasses. Some animals, like shrimp and bees, live in a vividly polarized world and use polarization-sensitive eyes to see what other species cannot see.

“But designing an instrument to detect polarization is difficult,” Krawczynski says, “because we need a lot of photons to measure it accurately. Whereas physicists can measure the energy or direction of a single photon, they need as many as 10,000 photons to detect a 5 percent polarization signal with high confidence.”

Inside X-Calibur

Sketch of X-Calibur shows its main components. X-rays focused on a scintillator rod by an assembly of X-ray mirrors collide with electrons in the rod and are scattered into solid-state detectors (gray bars), developed at Washington University, that wrap round the rod. The scattering directions encode information about the polarization properties of the incident X-rays.

The scintillator rod glows blue in the laboratory prototype of X-Calibur. The image shows the partially assembled instrument with three out of eight detector rings.

The scintillator rod at the heart of the X-Calibur experiment scatters X-rays into rings of detectors surrounding it.

The rod deflects X-rays by a process called Compton scattering, which was first observed by Arthur Holly Compton in 1923 at Washington University. The building that houses Krawczynski’s lab was named after Compton.

In this type of scattering, the X-ray photons colliding with electrons in the rod are scattered at an angle to their original direction of flight.

The rod is made of a “light” material that Compton scatters photons with a high likelihood towards “heavy” solid-state detectors, which efficiently absorb the photons.

If the incoming photons are polarized, the outgoing photons will be scattered preferentially perpendicular to the orientation of the vibrating electric field.

“If you can measure the directions in which the photons are scattered, you can infer the polarization direction of the X-rays,” Krawczynski says.

The assembled instrument will be flown in spring 2013 or fall 2014 in a 1,600-kilogram (3,500-pound) gondola developed by the Goddard Space Flight Center that will hang from a balloon at an altitude of 40 kilometers (25 miles).

NASA/Goddard Space Flight Center

X-Calibur will be installed on a gondola (above) suspended from a balloon for its observation run. The gondola was developed by Jack Tueller, a former graduate student at Washington University who now works at the Goddard Space Flight Center.

“The gondola will swing a bit, but we need to focus the telescope on a celestial object with an accuracy of a sixtieth of degree,” Krawczynski says.

The telescope, which is slowly spinning to minimize systematic measurement errors, is suspended in the gondola by a single high-pressure ball joint. The telescope acts like the rotor in a gimbaled gyroscope. No matter how its surroundings move, its optical axis remains firmly pointed in the same direction.

Aboard the gondola is an X-ray mirror developed by Hideyo Kunieda and his team at Nagoya University. The mirror looks more like a giant apple slicer than the usual bathroom mirror.

If X-rays strike a mirror at angles close to the perpendicular, they are likely to be absorbed, not reflected. To be reflected, they must hit the mirrors at grazing angles, typically less than 2 degree. To accommodate these physics, an X-ray mirror consists not of a single reflective layer but instead of a 256 nested cylindrical mirrors. These concentric mirrors act as a lens, focusing the X-rays onto the tiny scintillator pin at a distance of 8 meters.

Because of the mirror and features of the instrument are designed to maximize Compton events and discard imposter events, X-Calibur detects many more of the incoming X-rays and is roughly one order of magnitude more sensitive than competing experiments in the high-energy range.

What the telescope might spy

NASA/Goddard Space Flight Center/Schnittman et al.

In this simulation of X-ray emission near a black hole, colors correspond to radiation intensity and the black bars indicate the X-ray polarization direction. The disk is viewed almost edge-on. The outer parts of the disk emit X-rays polarized parallel to the plane of the disk. Close to the black hole, the curvature of spacetime warps the photon trajectories, and photons returning to the disk lead to a net-polarization perpendicular to the plane of the disk.

Already on the target list for X-Calibur are one pulsar (the Crab Nebula), two galactic black holes (Cyngus X-1 and GRS 1915+105), an accreting neutron star (Hercules X-1), and one supermassive extragalactic black hole (Markarian 421).

“The most exciting targets for the telescope are the black holes and their plasma outflows,” Krawczynski says. “One of the things GEMS and X-Calibur will be able to measure is how fast the black holes are spinning.”

In the binary system Cygnus X-1, for example, a 15-solar-mass black hole gobbles up matter from a companion star. Like water going down the drain, the material spirals toward the black hole, forming a flat disk that gets hotter and hotter as the material gets closer and closer to the event horizon of the black hole.

Near the outer edge of the accretion disk, Krawczynski says, the emitted X-rays are polarized parallel to the plane of the disk. Closer to the black hole, the black hole curves spacetime to such an extent that many X-rays originally traveling away from the disk return to the disk and are then scattered towards the observer.

“The net effect,” Krawczynski says, “is that we will see a 90-degree polarization swing produced by the gravity of the black hole.”

But that’s not all. The polarization swing will occur at an energy that depends on how fast the black hole is spinning.

“Black holes and their accretion disks shrink as they rotate,” Krawczynski says. “The faster the black hole spins, the closer is the accretion disk to the black hole, and the lower is the energy at which the polarization swing will be observed.

“The energy at which the polarization swings is thus a direct indicator of the spin of the black hole,” he says.

Black holes and pulsars are not the only celestial targets in Krawczynski’s sights. He mentions the possibility of testing the theory of general relativity near a black hole.

General relativity has been repeatedly validated in the wimpy gravitational fields of the Earth’s solar system. But what happens, Krawczynski wonders, close to a black hole where spacetime is tied into a knot, and the potential well plunges to infinity?

His eyes light up at the very thought.

Scientists characterize protein essential to survival of malaria parasite

Diana Lutz — 2012-01-06 00:00:00

Jez

Soon Goo Lee, a doctoral candidate at Washington University in St. Louis, about to click the mouse button to see whether six years of work will pay off and he will be the first to see the structure of a protein no one has ever seen before.

A biology lab at Washington University has just cracked the structure and function of a protein that plays a key role in the life of a parasite that killed 655,000 people in 2010.

The protein is an enzyme that Plasmodium falciparum, the protozoan that causes the most lethal form of malaria, uses to make cell membrane.

The protozoan cannot survive without this enzyme, but even though the enzyme has many look-alikes in other organisms, people do not make it. Together these characteristics make the enzyme an ideal target for new antimalarial drugs.

The research was published in the Jan. 6 issue of the Journal of Biological Chemistry (JBC) as “Paper of the Week” for that issue.

The work also will be featured in ASBMB Today (the newsletter of the American Society for Biological Molecular Biology, which publishes JBC), and it will be the topic of a JBC podcast.

Sweating the cold room

Wikimedia Commons

The protozoan Plasmodium falciparum gliding through a cell in the gut of a mosquito, its primary host. Although five different species of Plasmodium can cause malaria, Plasmodium falciparum causes the most severe disease.

The protein’s structure might have remained an enigma, had it not been for the “unreasonable optimism” of Joseph Jez, PhD, associate professor of biology in Arts & Sciences, which carried his team through a six-year-long obstacle course of failures and setbacks.

“What my lab does is crystallize proteins so that we can see what they look like in three dimensions,” Jez says. “The idea is that if we know a protein’s structure, it will be easier to design chemicals that would target the protein’s active site and shut it down,” Jez says.

The lastest discovery is the culmination of a project that began years before when Jez was working at the Danforth Plant Science Center in St. Louis and collaborating with scientists at the local biotech startup Divergence.

“At the time, C. elegans had just been sequenced and the Divergence scientists were looking at using it as an easy model to work out the biochemistry of parasitic nematodes,” Jez says.

C. elegans is a free-living nematode, or microscopic roundworm, but many nematodes are parasitic and cause disease in plants, livestock and people.

During this project, Lavanya Palavalli, a summer intern working with Jez, crystallized the C. elegans version of the enzyme. The job of the enzyme, phosphoethanolamine methyltransferase, thankfully abbreviated to PMT, is to add methyl groups to a starting molecule, phosophoethanolamine.

“When Soon Goo Lee later took up the project,” says Jez, “the plan was to try to grow better crystals of the C. elegans protein, ones good enough to get readable X-ray diffraction patterns.”

Two years later, the crystals were looking better, but still not good enough.

So Jez suggested that Lee go after homologous (look-alike) proteins in other organisms. “Even though the proteins are homologous, each has a different amino acid sequence and so will behave differently in the crystallizations,” Jez says.

“Lee went from working with two C. elegans proteins to three plant proteins, two other nematode proteins and then the Plasmodium protein,” Jez says.

“He took all six of those PMT versions into the crystallization trials to maximize his odds,” he adds.

“To crystallize a protein,” Jez says, “we put a solution of a salt or something else that might work as a desiccant in the bottom of a small well. And then we put a drop of our liquid protein on a microscope cover slip and flip it over the top of the well, so the drop of protein is hanging upside down in the well.”

“What we’re trying to do is to slowly withdraw water from the protein. It’s exactly like making rock candy, only in that case, the string hanging into the jar of sugar solution helps to withdraw water,” he says.

The difference is that sugar wants to form crystals and proteins are reluctant to do so.

“There are 24 wells to a tray, and we usually screen 500 wells per protein at first,” Jez says. “Lee had eight proteins and so his first pass was to screen 4,000 conditions. And then he had to try different combinations of ligands to the proteins and crystallize those. This is why it took a few years to finally get where he needed to go.”

Jez

Crystals growing in a drop of liquid protein look more like trapped insects than gemstones, but they’re crystals nonetheless.

Road trip!
The scientists need crystals — preferably nice, big ones —to stick in the path of an X-ray beam at Argonne National Laboratory in Chicago. (If the crystal is a good one, and all the atoms are lined up in a repeating array, the scattered X-rays will produce a clear pattern of spots.)

Embedded in that pattern is the mathematical information needed to back-calculate to the position of the atoms in the protein, a process a bit like throwing a handful of pebbles in a lake and then calculating where they landed by the pattern of waves arriving at the shoreline.

Wikipedia Commons

One of the proteins Lee worked with is made by Haemonchus contortus, or the Barber’s pole worm, a veterinary parasite that attaches itself to the lining of the stomach of a ruminant such as a sheep and feeds on its blood, leaving the animal emaciated and anemic.

Lee got the PMT from Haemonchus contortus to crystallize first, but there were technical issues with the diffraction pattern that would have made solving it technically and computationally very demanding.

“When the Plasmodium enzyme finally crystallized, Soon got four crystals kind of stacked on top of each other and each of them was paper thin,” Jez says.

“I never thought it would work, but we took them to Argonne anyway and he actually did surgery under the microscope and cracked off a little tiny piece of it.”

Jez

The diffraction pattern produced by X-rays scattering off the electrons in a crystal of Plasmodium PMT.

To everyone’s surprise, he got a clean diffraction pattern from the crystal. “Because the Plasmodium enzyme was the smallest one and the easiest to work on, we pushed that one first,” Jez says.

The moment of truth
“Once we had a Plasmodium crystal that was diffracting really well, we could try back-calculating to see whether we could extract the atom positions from the data,” Jez says.

After the computer finished its calculations, Lee clicked a mouse button to see the results, which would reveal whether his years of work finally would pay off.

Jez

What Lee saw when he clicked the mouse: an exceptionally clear electron density map back-calculated from the X-ray diffraction pattern.

When Lee clicked the mouse, he got an electron density map in exceptionally sharp focus.

“When you see a map like that, it’s like suddenly the wind has kicked up and you’re sailing free,” Jez says, “because there’s this moment, like, before you click that button, no one has ever seen how this protein is put together in three dimensions. You’re the first person to ever see it.

“The irony of it is we got such good quality diffraction pattern and electron density maps off such an ugly crystal,” he says.

Lock and load
“Once you have the electron density map, the task is to build a structure that matches the amino acid sequence of the protein,” Jez says.

“The first thing you do is put in the amino acid backbones and connect them together to form a chain. It’s like having a long thread, each inch of which is an amino acid, and your job is to take that thread and move it in three dimensions through that electron density map.”

The next step is to add the side chains that make one amino acid different from another, Jez says. “The amino acid sequence is known,” he says. “Your goal is to match the way you string together the amino acids in the electron density map to that sequence.”

Jez

A cartoon based on the electron density map makes it easier to see the protein’s structure and figure out how it works. The enzyme’s job is to add a methyl group — three times — to a starting molecule as part of a process for making cell membranes. In this cartoon, the phosphate is a stand-in for the starting molecule and the green molecule is the one that donates a methyl group. Both are positioned in the active site of the enzyme, the pocket where the chemistry takes place.

“Once you have the overall structure, you can start to figure out how the enzyme works. The PMT enzyme is trying to join two molecules,” Jez says. “To do that, it has to lock them in place so that the chemistry can happen, and then it has to let go of them.

“We think the protein has a lid that opens and closes,” he says. “The active site stays open until the substrates enter, and then the lid clamps down, and when it clamps down it actually puts the substrates together.”

Calling Bill and Melinda Gates
Not only do infections by Plasmodium falciparum cause the most severe form of malaria, about 40 percent of the human population lives in areas where the parasite is endemic. Moreover, drugs that used to be effective against malaria are beginning to fail, in part because widespread drug counterfeiting has led to resistance.

New anti-malarial drugs are desperately needed, and the PMT protein is an ideal target. If PMT is disabled, the protozoan can’t make cell membranes and it dies. Moreover, a drug that would kill Plasmodium might have minimal side effects on patients.

Although the process of identifying compounds that would target PMT is in the early stages, a handful of anti-parasitical compounds used to treat diseases are known to block PMT as well.

As for Lee, he has had a hard go of it, but now things are breaking his way. Plasmodium PMT is giving up its secrets, and the plant and nematode PMTs are coming along as well.

When he clicked the mouse button and a clean electron density map came up, he says, it was like seeing “the light at the end of a five-year-long tunnel.”

MEDIA ADVISORY: McCaskill continues energy tour with Jan. 9 visit to Washington University in St. Louis

2012-01-06 00:00:00

WHO: U.S. Sen. Claire McCaskill will participate in a roundtable discussion with Washington University administrators and energy researchers, and the region’s energy leaders on the nation’s urgent energy needs while addressing important environmental concerns.

WHAT: Roundtable energy discussion and tour of Washington University’s Ultrafast Laser Facility.

WHERE: Washington University’s Brauer Hall, Room 3015, near the corner of Skinker Boulevard and Forest Park Parkway. From Forest Park Parkway, enter Danforth Campus at Hoyt Drive. Turn at first left (east) into parking lot. Brauer Hall, dedicated to teaching and research in energy and environmental engineering at WUSTL’s School of Engineering & Applied Science, is the second building on left.

WHEN: Noon on Monday, Jan. 9, 2012

MEDIA ACCESS: The media are invited to cover the roundtable discussion and the 1 p.m. laser facility tour. McCaskill and other discussion participants will be available for interviews during the tour or immediately following the tour at 1:15.

WHY: McCaskill is visiting WUSTL as part of her statewide Hometown Energy Tour that began Jan. 5, focused on finding “practical, accessible, and affordable” solutions to meet the nation’s energy needs.

As one of the country’s leaders in the development of new energy sources as well as one of the region’s leaders in helping St. Louis become a worldwide center for bioenergy research, Washington University is playing a major role in the effort to provide clean energy resources to the world.

The university is also a leader in sustainability initiatives and programs. Among its notable accomplishments, Washington University is the first university in the country to ban the sale and use of bottled water throughout its main campus and its Living Learning Center shares the world’s first full “Living Building” certification.

The Ultrafast Laser Facility that McCaskill will tour is part of WUSTL’s Photosynthetic Antenna Research Center (PARC), established with a $20 million research award — the largest ever on the Danforth Campus — from the U.S. Department of Energy to do research on novel energy initiatives. PARC researchers are studying forms of energy based on the principles of light harvesting and energy funneling.

PARC comes under the umbrella of WUSTL’s International Center for Advanced Research in Energy and Sustainability (I-CARES), started in 2007 to foster research on energy, environment and sustainability that can contribute to rapid progress in addressing the world’s energy needs.

Pions don’t want to decay into faster-than-light neutrinos, study finds

Diana Lutz — 2011-12-23 00:00:00

When an international collaboration of physicists came up with a result that punched a hole in Einstein’s theory of special relativity and couldn’t find any mistakes in their work, they asked the world to take a second look at their experiment.

Responding to the call was Ramanath Cowsik, PhD, professor of physics in Arts & Sciences and director of the McDonnell Center for the Space Sciences at Washington University in St. Louis.

Cowsik

Online and in the December 24 issue of Physical Review Letters, Cowsik and his collaborators put their finger on what appears to be an insurmountable problem with the experiment.

The OPERA experiment, a collaboration between the CERN physics laboratory in Geneva, Switzerland, and the Laboratori Nazionali del Gran Sasso (LNGS) in Gran Sasso, Italy, timed particles called neutrinos traveling through Earth from the physics laboratory CERN to a detector in an underground laboratory in Gran Sasso, a distance of some 730 kilometers, or about 450 miles.

OPERA reported online and in Physics Letters B in September that the neutrinos arrived at Gran Sasso some 60 nanoseconds sooner than they would have arrived if they were traveling at the speed of light in a vacuum.

Neutrinos are thought to have a tiny, but nonzero, mass. According to the theory of special relativity, any particle that has mass may come close to but cannot quite reach the speed of light. So superluminal (faster than light) neutrinos should not exist.

The neutrinos in the experiment were created by slamming speeding protons into a stationary target, producing a pulse of pions — unstable particles that were magnetically focused into a long tunnel where they decayed in flight into muons and neutrinos.

The muons were stopped at the end of the tunnel, but the neutrinos, which slip through matter like ghosts through walls, passed through the barrier and disappeared in the direction of Gran Sasso.

In their journal article, Cowsik and an international team of collaborators took a close look at the first step of this process. “We have investigated whether pion decays would produce superluminal neutrinos, assuming energy and momentum are conserved,” he says.

The OPERA neutrinos had energies of about 17 gigaelectron volts. “They had a lot of energy but very little mass,” Cowsik says, “so they should go very fast.” The question is whether they went faster than the speed of light.

“We’ve shown in this paper that if the neutrino that comes out of a pion decay were going faster than the speed of light, the pion lifetime would get longer, and the neutrino would carry a smaller fraction of the energy shared by the neutrino and the muon,” Cowsik says.

“What’s more,” he says, “these difficulties would only increase as the pion energy increases.

“So we are saying that in the present framework of physics, superluminal neutrinos would be difficult to produce,“ Cowsik explains.

In addition, he says, there’s an experimental check on this theoretical conclusion. The creation of neutrinos at CERN is duplicated naturally when cosmic rays hit Earth’s atmosphere.

A neutrino observatory called IceCube detects these neutrinos when they collide with other particles generating muons that leave trails of light flashes as they plow into the thick, clear ice of Antarctica.

“IceCube has seen neutrinos with energies 10,000 times higher than those the OPERA experiment is creating,” Cowsik says..“Thus, the energies of their parent pions should be correspondingly high. Simple calculations, based on the conservation of energy and momentum, dictate that the lifetimes of those pions should be too long for them ever to decay into superluminal neutrinos.

ICE.WISC.EDU / Pete Guest

The IceCube experiment in Antarctica provides an experimental check on Cowsik’s theoretical calculations. According to Cowsik, neutrinos with extremely high energies should show up at IceCube only if superluminal neutrinos are an impossibility. Because IceCube is seeing high-energy neutrinos, there must be something wrong with the observation of superluminal neutrinos.

“But the observation of high-energy neutrinos by IceCube indicates that these high-energy pions do decay according to the standard ideas of physics, generating neutrinos whose speed approaches that of light but never exceeds it.

Cowsik’s objection to the OPERA results isn’t the only one that has been raised.

Physicists Andrew G. Cohen and Sheldon L. Glashow published a paper in Physical Review Letters in October showing that superluminal neutrinos would rapidly radiate energy in the form of electron-positron pairs.

“We are saying that, given physics as we know it today, it should be hard to produce any neutrinos with superluminal velocities, and Cohen and Glashow are saying that even if you did, they’d quickly radiate away their energy and slow down,” Cowsik says.

“I have very high regard for the OPERA experimenters,” Cowsik adds. “They got faster-than-light speeds when they analyzed their data in March, but they struggled for months to eliminate possible errors in their experiment before publishing it.

“Not finding any mistakes,” Cowsik says, “they had an ethical obligation to publish so that the community could help resolve the difficulty. That’s the demanding code physicists live by,” he says.

Editors’ picks: 2011 WUSTL news stories worth a second look

2011-12-15 00:00:00

WUSTL news editors picked 11 stories from 2011 — some new, some old — but all worth a second look as we head into 2012.

Topics include tips for paying off holiday debts; why your gift list should not include the Ozark’s endangered collared lizard; and why Waffle House is a model of preparedness for businesses facing severe winter weather.

2011’s best research news stories offer insight on why “being good this year” is the norm for most humans; how social work education is helping adults make mid-life career changes; and how doctors are working to ensure that memories of painful surgeries will not be among those recalled on New Year’s Eve.

To reduce holiday debt, focus on high interest loans

The presents are purchased. The feasts have been bought. The tree is trimmed. Now comes the worst part of the holidays — the credit card bill. What’s the best way to pay it off? Pay down the loan with the highest interest rate. But consumers often take a slightly different approach, says a consumer behavior expert at Olin Business School at Washington University in St. Louis. Video included.

Waffle House Index measures disaster’s impact one breakfast a time

What can Waffle House teach about disaster preparedness and risk management as we brace for the logistical challenges of extreme winter weather? Plenty, says a supply chain expert at Olin Business School at Washington University in St. Louis. Video included.

10 tips for preventing weight gain over the holidays

Many websites and magazine articles offer ideas about how to lose weight over the holidays, but Connie Diekman, director of university nutrition at Washington University in St. Louis, says that people need to realize that weight loss during this time generally isn’t realistic. A little advance planning can ensure that, while people may not actually lose weight, they can keep weight gain in check.

Humans by nature cooperative, altruistic, social

Charitable donations and a general feeling of goodwill may increase during the holiday season, but research in the new book Origins of Altruism and Cooperation, edited by WUSTL professors Robert W. Sussman, PhD, and C. Robert Cloninger, MD, show that humans are by nature cooperative, altruistic and social all year long. The book’s authors argue that humans only revert to violence when stressed, abused, neglected or mentally ill.

Civil rights era preserved through film archive

The film adaptation of Kathryn Stockett’s The Help — which has been nominated for numerous awards this month, including the Screen Actors Guild’s best film cast and best female actor — depicts a fictional slice of the 1960s Civil Rights movement. Washington University in St. Louis holds one of the largest archives of civil rights media in the United States, thanks to the Henry Hampton collection and Eyes on the Prize: America’s Civil Rights Years, 1954-1965, a six-episode documentary on the American civil rights movement. Video included.

Restoring the collared lizard

Biologist Alan R. Templeton, PhD, fell in love with the eastern collared lizard that lives in the hot, dry Ozark glades when he was 13. By the time he returned from postgraduate work, 75 percent of the lizard populations had vanished. Over the next 30 years, he reintroduced lizards to a few glades and then sought to establish the disturbance regime that had once sustained them by advocating for the highly controversial process of landscape-scale burning. The cover article in the September issue of Ecology celebrates the success of this prolonged effort. Slideshow included.

Cosmic voyager has a layover in St. Louis

Last January, two amateur meteorite hunters dropped by the Washington University in St. Louis office of Randy Korotev, PhD, to show him their latest purchase: a 17-kilogram pallasite meteorite found in 2006 near Conception Junction (population 202) in northwest Missouri. Korotev, an expert in lunar meteorites, identified the stone as a piece of an asteroid. His lab also analyzed crystals within the rock to help identify its body of origin, eventually referring the meteorite hunters to UCLA for analysis of the metal in which the crystals are embedded. Video included.

Orangutan genome decoded; DNA more diverse than human’s

An international team of scientists, led by Washington University School of Medicine in St. Louis, has decoded the DNA of a Sumatran orangutan. With this genome as a reference, the scientists then sequenced the genomes of five additional Sumatran and five Bornean orangutans, they report in the journal Nature. Video included.

Preventing memories of surgery

Anesthesiology researchers have shown that a device to reduce the risk that patients will recall their surgery does not lower the risk of intraoperative awareness any more than a less expensive method. Unintended intraoperative awareness occurs when a patient becomes aware during surgery and later remembers being in pain or feeling distress during the operation. Video included.

Study: Education helps those over 40 seeking new careers

Americans are remaining in the workforce longer and many are changing or advancing their careers well past age 40. The Brown School at Washington University in St. Louis decided to study the experiences of their students who came to get their MSW after the age of 40. The survey focuses on pathways to graduate school, their experience in the classroom as well as the field and their post-MSW careers. Nancy Morrow-Howell, PhD, professor of social work at the Brown School, says that these results can be applied to other graduate programs, particularly in fields that may face labor shortages in the future, such as education, health and social services. Video included.

Can U.S. law handle polygamy?

HBO’s Big Love and TLC’s reality-TV offering Sister Wives have thrust polygamy into popular culture in the United States. Estimates are that somewhere between 50,000-100,000 families in this country are currently risking criminal prosecution by practicing plural marriage. “Putting aside whether you think polygamy is ‘right’ or ‘wrong,’ it is important to look at whether U.S. law is up to regulating marital multiplicity,” says Adrienne Davis, JD, an expert on gender relations and the William M. Van Cleve Professor of law at Washington University in St. Louis. She proposes some default rules that might accommodate polygamy, while ensuring against some of its historic and ongoing abuses. Video included.

Close family ties keep cheaters in check, study finds

Diana Lutz — 2011-12-15 00:00:00

Scott Solomon

A forest of the fruiting bodies of the social amoeba Dictyselium discoideum. An amoeba that must succeed at both single-celled and multicellular living to pass on its genes, Dicty allows scientists to ask questions about cooperation and cheating in multicellular organisms.

Any multicellular animal, from a blue whale to a human being, poses a special difficulty for the theory of evolution. Most of the cells in its body will die without reproducing, and only a privileged few will pass their genes to the next generation.

How could the extreme degree of cooperation multicellular existence requires ever evolve? Why aren’t all creatures unicellular individualists determined to pass on their own genes?

Joan Strassmann, PhD, and David Queller, PhD, a husband and wife team of evolutionary biologists at Washington University in St. Louis, provide an answer in the Dec. 16 issue of the journal Science. Experiments with amoebae that usually live as individuals but must also join with others to form multicellular bodies to complete their life cycles showed that cooperation depends on kinship.

If amoebae occur in well-mixed cosmopolitan groups, then cheaters will always be able to thrive by freeloading on their cooperative neighbors. But if groups derive from a single cell, cheaters will usually occur in all-cheater groups and will have no cooperators to exploit.

The only exceptions are brand new cheater mutants in all-cooperator groups, and these could pose a problem if the mutation rate is high enough and there are many cells in the group to mutate. In fact, the scientists calculated just how many times amoebae that arose from a single cell can safely divide before cooperation degenerates into a free-for-all.

The answer turns out to be 100 generations or more.

So population bottlenecks that kill off diversity and restart the population from a single cell are powerful stabilizers of cellular cooperation, the scientists conclude.

In other words our liver, blood and bone cells help our eggs and sperm pass on their genes because we passed through a single-cell bottleneck at the moment of conception.

The social amoebae

Wikipedia Commons

Some stages in the life cycles of a social amoeba. When bacteria are scarce, the amoebae send out a distress signal, rush together to form a loose aggregate (second row, right), then a tight aggregate (second row, middle) and then a finger (second row, left). The finger falls over and becomes a slug (front row, far left) that crawls toward heat and light. Once the slug finds a suitable spot, the back end spreads out, raising the front end in the air (the “Mexican hat” at far left). The front end elongates to form a stalk and the back end of the slug flows up the stalk, reorganizing itself at the top into a ball of spores (back row, right).

Queller, the Spencer T. Olin professor, and Strassmann, professor of biology, moved to WUSTL from Rice University this summer, bringing a truckload of frozen spores with them.

Although they worked for many years with wasps and stingless bees, Queller and Strassmann’s current "lab rat" is the social amoeba Dictyostelium discoideum, known as Dicty for short.

The social amoebae can be found almost everywhere; in Antarctica, in deserts, in the canopies of tropical forests, and in Forest Park, the urban park that adjoins Washington University.

The amoebae spend most of their lives as tiny amorphous blobs of streaming protoplasm crawling through the soil looking for E. coli and other bacteria to eat.

Things become interesting when bacteria are scarce and the amoebae begin to starve. They then release chemicals that attract other amoebae, which follow this trail until they bump into one another.

A mound of some 10,000 amoebae forms and then elongates into a slug a few millimeters long that crawls forward (but never backward) toward heat and light.

The slug stops moving when it has reached a suitable place for dispersal, and then the front 20 percent of the amoebae die to produce a sturdy stalk that the remaining cells flow up and there become hardy spores.

Crucially, the 20 percent of the amoebae in the stalk sacrifice their genes so that the other 80 percent can pass theirs on.

When Strassmann and Queller began to work with Dicty in 1998, one of the first things they discovered was that the amoebae sometimes cheat.

Dennis Welker of Utah State University had given them a genetically diverse collection of wild-caught clones (genetically identical amoebae). They mixed amoebae from two clones together and then examined the fruiting bodies to see where the clones ended up. Each fruiting body included cells from both clones, but some clones contributed disproportionately to the spore body. They had cheated.

How can a blob of protoplasm cheat? The answer, it turns out, is many different ways.

“They might,” Queller says, “have a mutation that makes an adhesion molecule less sticky, for example, so that they slide to the back of the slug, the part that forms spores.”

“But there are tradeoffs,” Strassmann says, “because if you’re too slippery, you’ll fall off the slug and lose all the advantages of being part of group.”

Natural born cheaters
Mulling this over, Strassmann and Queller began to wonder if it would be possible to break the social contract among the amoebae by setting up conditions where relatedness was low and each clonal lineage encountered mostly strangers and rarely relatives.

The low-relatedness experiment started with one cell that was allowed to divide until its descendants formed fruiting bodies. The spores were harvested and roughly a million were plated out again. This procedure was repeated 30 times for 24 different lines of cells.

Together with then-graduate student, Jennie Kuzdzal-Fick, they set up an experiment to learn what happened to cheating as heterogeneous (low relatedness) populations of amoebae evolved.

“At the end of the experiment, we assessed the cheating ability of the descendants by mixing equal numbers of descendants and ancestors and checking to see whether the descendants ended up in the stalks or the spores of the fruiting bodies,” Strassmann says.

They found that in nearly all cases, the descendants cheated their ancestors. What’s more, when descendent amoebae were grown as individual clones, about a third of them were unable to form fruiting bodies.

Many of the mutants, in other words, were “obligate” cheaters. Having lost the ability to form their own fruiting bodies, they were able to survive only by freeloading, or taking advantage of the amoebae that had retained the ability to cooperate.

This result, Queller and Strassmann say, shows that cheater mutations that threaten multicellularity occur naturally and are even favored — as long as the population of amoebae remains genetically diverse.

What happens in the wild?
But the scientists were aware that obligate cheaters are either very rare or altogether missing among wild social amoebae. They had not found any obligate cheaters in the more than 2,000 wild clones they have sampled.

They also knew that in the wild, the amoebae in fruiting bodies are close kin, if not clones.

What prevents cooperation in wild populations from degenerating into the laboratory free-for-all? Could the difference be that the amoebae in the laboratory were distant relations and those in the wild are kissing kin?

Suppose, the scientists thought, one amoeba ventured alone into a pristine field of bacteria. As it grew and multiplied, making copies of itself, how long would it take for cheating mutations to appear (what was the mutation rate) and how successfully would these mutations proliferate (how strongly would they be selected)?

To establish the mutation rate, Strassmann and Queller together with graduate student Sara Fox ran what is called a mutation accumulation experiment.

In the mutation accumulation experiment, amoebae were allowed to reproduce until they formed a visible plaque, and then one was picked at random and carried to a new plate where it was allowed to reproduce and so on. Because the amoebae were picked at random and never allowed to form fruiting bodies, natural selection wasn’t removing harmful mutations; instead they were “fixed,” or became a permanent part of a line’s genome.

In this experiment, amoebae that mutated didn’t have to compete against amoebae that were faithful replicators. In the absence of selection, all but the most severe mutations were also reproduced and became a permanent part of the lineage’s genome.

The scientists allowed 90 different lines of amoebae to accumulate mutations in this way.

“At the end,” Queller says, “we found that among those 90 lines not a single one had lost the ability to fruit. So that’s almost 100 lines, almost a thousand generations, so 100,000 opportunities to lose fruiting and none of them did.

“That allowed us, using statistics, to put an upper limit on the rate at which mutations turn a cooperator into an obligate cheater,” he says.

The rate was low enough that if fruiting bodies were forming in the wild from amoebae that were all descended from one spore, cheating would never be an issue.

What this has to do with elephants and blue whales
But the scientists were inquisitive enough to ask another, bigger question. They used calculations invented for population genetics to ask how many times the amoeba could divide — theoretically — before cheating became a problem.

What if, they asked, we let an initial single amoebae divide until there were as many of amoebae as there are cells as a fruit fly and then transferred one amoeba and allowed it to divide until the daughter colony reached fruit-fly size, and so on?

What if we let the colonies grow to human size? To elephant size? To blue whale size? Would the cheaters bring down the whale-sized Dicty colony?

The answer, it turned out, was no.

A whale-sized Dicty colony is not the same thing as a whale, but nonetheless the experiments suggest how organisms, over the course of evolution, have sidestepped the cheating trap and maintained the levels of cooperation multicellular bodies demand.

“A multicellular body like the human body is an incredibly cooperative thing,” Queller says, “and sociobiologists have learned that really cooperative things are hard to evolve because of the potential for cheating.

“It’s the single-cell bottleneck that generates high relatedness among the cells that, in turn, allows them to cooperate, ” he says.

Our liver cells have no kick against our sperm or egg cells, in other words, because they’re all nearly genetically identical descendants of a single fertilized egg.

Lead levels in drinking water spike when copper and lead pipes joined

Diana Lutz — 2011-12-15 00:00:00

Joe Angeles/WUSTL

Old lead water pipes are spliced to brand new copper pipes in Dan Giammar’s lab at Washington University in St. Louis using either a plastic or a brass fitting. Homeowners end up with a similar setup if they decline to have their portion of a service line replaced. Giammar (above in red) has found that the juxtaposition of two dissimilar metals leads to galvanic corrosion that releases lead into the water.

Lead pipes once used routinely in municipal water distribution systems are a well-recognized source of dangerous lead contamination, but new research from Washington University in St. Louis suggests that the partial replacement of these pipes can make the problem worse.

The research shows that joining old lead pipes with new copper lines using brass fittings spurs galvanic corrosion that can dramatically increase the amount of lead released into drinking water supplies.

“Work done in our laboratory shows galvanic corrosion in joined service lines is significant and lasts for a long time,” says Dan Giammar, PhD, the Harold D. Jolley Career Development Associate Professor in the Department of Energy, Environmental & Chemical Engineering at Washington University in St. Louis.

His study, published in the Proceedings of the 2011 Water Quality Technology Conference, suggests that safety-minded, lead-pipe-removal programs at water utilities across the country actually may be increasing the risk of lead exposure for water customers.

An experiment running in his aquatic chemistry lab shows why. It features 80- to 100-year-old lead water pipes that were dug out of the ground in Washington, D.C., and shipped to his St. Louis laboratory. Some of the lead pipes have been cut and then joined with brass couplings to brand new copper pipe.

This setup mimics what happens if a utility company is replacing lead service lines and homeowners decline to have their sections of the lines replaced.

A service line runs from the main to the home. The utility owns the part from the main to the homeowner's property line and the homeowner owns the part from the property line to the house. The utility cannot replace the homeowner’s half of the line unless the homeowner gives permission and pays for replacement. In the U.S. only 10 percent of homeowners agree to the charge.

“Since you started with a whole lead pipe and you now have half a lead pipe, you might think your problem would be half of what it was or — maybe — completely unchanged,” Giammar says.

His experiment reveals that instead, it could be far worse. The joined lead-copper pipe in his lab releases five times more lead than did the original lead pipe.

The lead is released by galvanic corrosion, a process set up whenever two dissimilar metals are immersed in a conducting liquid.

The same thing happens if lasagna or another acidic dish is made in a stainless steel pan, covered with aluminum foil, and placed in a refrigerator. The two metals and the lasagna act as a galvanic cell, and some of the aluminum may migrate out of the foil and plate out on the surface of the lasagna.

Joe Angeles/WUSTL

The old lead pipes from Washington, D.C., must be “conditioned” for several months before they’d start behaving the way they behaved when they were buried in the ground, Giammar (right) explains to doctoral candidates Yin Wang and Vrajesh Mehta. To condition them, the pipes are filled daily with water that simulates district water.

The Lead and Copper Rule
The project to measure galvanic corrosion of lead pipes was the third Giammar has done for the Water Research Foundation, an organization of water utilities that allows them to pool their money to support research on problems of common interest.

Giammar, who calls himself a heavy metals guy, did his doctoral work on uranium contamination of soil and groundwater, work relevant to the far-flung branches of the Manhattan Project that purified uranium for the atomic bomb during World War II.

He still works on uranium remediation, but when he moved to St. Louis in 2002, he thought that he really ought to work on lead as well, because Missouri has historically been one of the two largest lead-producing states in the country. The other is Alaska.

Giammar began with experiments directed at understanding exactly what happens when phosphates are worked into lead contaminated soil. Under the right conditions, the phosphate will bind to the lead and immobilize it.

Phosphate remediation of lead contaminated soils had been successful in Joplin, Mo., a town located in the Tri-State district, an historic lead-zinc mining district that takes in parts of Missouri, Kansas and Oklahoma.

While Giammar was working with phosphates and soils, the media began reporting that lead levels in the tap water in Washington, D.C., were higher than before and indeed were higher than national drinking water standards allowed.

Lead, as Giammar says, is a “xenobiotic” element (literally foreign to living systems). Unlike some metals, it serves no biological purpose and only does harm. But lead pipes weren’t outlawed in new construction until 1978.

That the district knew it had a problem was remarkable in itself. The levels of lead in drinking water weren’t regulated until 1991, when the Lead and Copper Rule was passed.

The lead levels in Washington, D.C., drinking water began to rise in 2001.

The case of Washington, D.C., water

The lead levels rose for an interesting reason, says Giammar. The district water utility was trying to improve water quality.

In the U.S., he explains, water is delivered with a disinfectant still in it. There are two ways of chlorinating water to disinfect it. Utilities either use free chlorine, which is essentially bleach, or they use chloramines, which are essentially bleach combined with ammonia.

Free chlorine is a better disinfectant but it also forms higher concentrations of chlorinated disinfection byproducts — things like chloroform — that we don’t want in our drinking water, Giammar says.

In an effort to decrease the concentrations of disinfection byproducts, the district switched from chlorine to chloramine.

This is where the water chemistry comes in. “The lead pipe, in itself, is not much of a concern,” Giammar says. Pure lead, lead 0 as it’s called, is not particularly reactive or soluble, which is one of the reasons people made plumbing out of it. Lead pipes last much longer than iron pipes.

But lead can oxidize — essentially corrode. The lead species that then form determine how much lead ends up in the water. The various forms of lead in the +2 oxidation state are all more soluble than lead 0, but lead sulfate is more soluble than lead carbonate, which is in turn more soluble than lead phosphate. (The oxidation state of an element is a rough measure of how many electrons it has "lost to other, nearby elements that are attracting the electrons more strongly.)

When it comes to lead in the +4 oxidation state there’s a twist.

“If you have a strong oxidant, you can form species with lead in the +4 oxidation state,” Giammar says. “These have very low solubility but they’re only stable in the presence of a strong oxidant. As soon as the strong oxidant goes away, the lead +4 is no longer stable. It starts to come back to lead +2, and it can release the lead quite quickly.”

The free chlorine the district had been using is a very strong oxidant. The chloramines they switched to are less strong.

“So when they switched to chloramines, the pipe scale that had formed over years of chlorine treatment began to release lead into the water,” Giammar says. It was a classic example of an unintended consequence.

What the district case demonstrates, Giammar says, is that tap water is a manufactured product, not a natural resource. The water leaving the treatment plant can have essentially no lead in it, but by the time it reaches the faucet that could have changed.

The lead comes from the piping, but whether it is released depends on the chemistry of the water running through the distribution system.

Looking at water chemistry
When he read about the district problem, Giammar wrote a proposal to the Water Research Board offering to study the chemistry of the insides of pipes, particularly the dissolution rates of lead phosphates, lead carbonates and the lead +4 oxides, as a function of pH, added phosphate and disinfectants.

“That was our first entry into the field of lead and drinking water,” he says.

“We knew pH would be an important variable,” he says. “You don’t want your pH to fall too low, especially for the lead carbonates, which dissolve at lower pH.”

“But we didn’t realize how important pH was. We studied water samples with a pH of 10, 8.5 and 7.5. You wouldn’t think there would be a much of a difference between a pH of 8.5 and 7.5, but there was.

“In some cases, the pH made the difference between a lead concentration that met the drinking water standard and one that didn’t.”

St, Louis water

“You might be surprised to know that the pH of St. Louis drinking water is 9 to 9.5," Giammar says, “much higher than the pH of distilled water, which is 7.”

In fact, it is heading toward milk-of-magnesia territory.

He explains that the pH of the Missouri River is about 8, because the river flows through limestone, which makes the water somewhat alkaline.

The limestone also makes the water hard, meaning it contains high levels of calcium and magnesium. So when it reaches the St. Louis water treatment plants, the pH is raised to between 10 and 11 to precipitate out some of the calcium carbonate and soften the water. The water utility then lets the pH drift back down to somewhere between 9 and 9.5 before the water is delivered.

“It’s a nice stable water with good water chemistry,” Giammar says. “Quite non-corrosive, has a good stable pH. They do all right with their distribution system,” he says.

By the way, St. Louis water is disinfected with chloramines rather than chlorine.

Phosphate also turned out to be important. “It had a huge impact on the dissolution rates of all the lead corrosion products we studied,” says Giammar.

So one way to bring down lead levels is to add phosphate. But phosphate costs money, so the utilities want to add as little of it as they can to produce a good-quality water.

“It’s never going to be a one-size-fits all solution because the source-water compositions are different,” says Giammar, “but we came up with some pretty strong recommendations.”

The final report on the project, “Influence of Water Chemistry on the Dissolution and Transformation Rates of Lead Corrosion Products,” was published last year.

Should you let the tap run?
“Another thing we studied in that first project,” Giammar says, “was whether we should be more worried about reaction rates or about the equilibrium state of the reactions.

“To put it another way, if you let the water sit in the pipes for six hours, will it be different from water that sat in the pipes for only an hour?”

It turned out that most lead species dissolve relatively quickly, so reaction rates are not particularly important. The water is the same no matter how long the water has been sitting in the pipes.

But this isn’t true of the lead +4 oxides, the material that formed the scale inside the Washington, D.C., pipes. “They are never at equilibrium with the water flowing over them,” Giammar says. “Instead everything depends on the rate at which those oxides form or the rate at which they dissolve.”

So Giammar proposed a second project for the Water Research Foundation just to study the lead +4 oxides. “They’re fascinating solids,” he says.

Then Giammar’s lab picked up a third project. “A little over a year ago, I got a call from an environmental engineer in Washington, D.C., who was looking at something called galvanic corrosion and its potential to release lead into drinking water,“ he says.

This is the project that led to the centenarian lead pipe experiment now taking up much of the bench space in his lab.

Unlike some of the other water problems he has studied, galvanic corrosion is national in scope. The Environmental Protection Agency is concerned enough that it has appointed a science advisory board to make recommendations on how best to deal with it, Giammar says.

How low can we go?
It’s difficult to talk about lead in a sensible way. The current threshold for drinking water is 15 micrograms per liter, Giammar says. And while there’s talk in the community about lowering the allowable levels of some water contaminants, lead is not among them.

Environmental lead is ubiquitous and everyone has measurable levels of lead in their blood. We are exposed to it through dust and air as well as through water, thanks in part to the tetraethyl lead added to gasoline as an antiknock compound for 80 years.

“If your dominant exposure is through dust, there’s little benefit to ratcheting down your exposure to water even further,” Giammar says.

But, he says, because of the Lead and Copper Rule, water utilities now monitor lead levels. And he learned at a recent conference that during the most recent monitoring period, only 30 utilities had lead levels above the drinking water standard.

That may seem like a lot, he said, but there are roughly 54,000 water utilities in the U.S.