80beats

China Puts 2 Men to Death Over Tainted Milk Scandal

Andrew Moseman — Tue, 24 Nov 2009 22:36:10 +0000

China has dished out justice in the tainted milk case, and severe justice at that. The country has executed two men, Zhang Yujun and Geng Jinping, convicted in January of crimes connected to last summer’s powered milk and infant formula contamination incident, which killed six children and sickened about 300,000 people in total.

Zhang, a farmer, produced some 770 tonnes of the powder from July 2007 to August 2008 which was laced with an industrial chemical, melamine, used in the manufacture of plastics and fertiliser [The Telegraph]. Geng was convicted of selling the powder to dairy brokers. The Supreme Court reviewed the cases before the executions, now done with lethal injection, took place. Nineteen other people were convicted of crimes; three got life sentences.

Melamine can cause kidney stones and kidney failure in humans, and has turned up in tainted pet food in the United States. Twenty-two Chinese dairy farms were found to have sold the bad milk, and in all paid about $160 million in damages.

The timing of the initial government response raised some eyebrows abroad. The scandal, which erupted in September last year, highlighted shoddy food safety standards in China and the readiness of the authorities to hush up problems that could have cast a shadow over the Beijing Olympics in August [The Times]. According to The Times, the toxic milk first sickened people in March of 2008, but the product wasn’t recalled until September.

Image: Wiki Commons

Scientists Discover a Perfect Blue Pigment—Entirely by Accident

Brett Israel — Tue, 24 Nov 2009 19:38:29 +0000

Scientists say that a thousand-year quest–one that you probably didn’t even know about–has accidentally come to an end. Painters and fabric makers can rest easy because Mas Subramanian and his research team at Oregon State University have created a near-perfect blue pigment. Blue pigments of the past have often been expensive (ultramarine blue was made from the gemstone lapis lazuli, ground up), poisonous (cobalt blue is a possible carcinogen and Prussian blue, another well-known pigment, can leach cyanide) or apt to fade (many of the organic ones fall apart when exposed to acid or heat) [The New York Times].

The new pigment popped up when the researchers were mixing manganese oxide, which is black, with other chemicals and then heating them up to high temperatures to study their electronic properties. One day, Subramanian was poking around in his lab when he noticed a graduate student removing a sample from the furnace that was brilliant blue.

The 2,000-degree-Fahrenheit furnace created a crystal structure that allowed the manganese ions to absorb red and green wavelengths of light while reflecting blue wavelengths. White yttrium oxide and pale yellow indium oxide are also required to stabilize the crystal structure. Subramanian said the pigment is safe, but far from cheap, since indium is quite costly, so they are trying to substitute cheaper oxides for indium. “Basically, this was an accidental discovery,” said Subramanian. “We were exploring manganese oxides for some interesting electronic properties they have, something that can be both ferroelectric and ferromagnetic at the same time. Our work had nothing to do with looking for a pigment” [UPI]. Regardless, their research appears in the Journal of the American Chemical Society.

Image: Oregon State University

A Silent Hell: For 23 Years, Man Was Misdiagnosed as a Coma Patient

Andrew Moseman — Tue, 24 Nov 2009 18:27:16 +0000

From 1983 to 2006, the Belgian man Rom Houben was misdiagnosed as a coma patient. In fact, doctors say, he was conscious for all those years, but incapable of communicating with doctors or family members who leaned over his bedside. But neuroscientist Steven Laureys finally caught the 23-year mistake. Laureys just published a paper on the case in BMC Neurology, spurring wonder at the remarkable case—and skepticism that Houben is truly “communicating” now.

Houben was paralyzed in 1983 after a vicious car crash, and doctors incorrectly diagnosed him as being in a persistent vegetative state until 2006. An expert using a specialized type of brain scan that was not available in the 1980s finally realized it, and unlocked Houben’s mind again [AP]. Houben indeed had an almost normal brain, his PET scan showed, and doctors say they clinched his consciousness by having him move his foot and then spell words on a touchscreen.

The team contends that many more similar cases could be misdiagnosed. A study carried out last year on 103 patients by Laureys and his colleagues at Liege’s Coma Science Group found that 41 per cent of patients in a Minimally Conscious State (MCS) were misdiagnosed as being in the much more serious Vegetative State (VS) [CNN].

Houben’s mother was never convinced by that her son was completely vegetative, and her persistent search for new doctors and new brain tests eventually led to Dr. Laureys’ discovery. According to news reports, Houben can now communicate with a computer and keyboard system, which he has used to recount his two-decades-plus of frustration. “I screamed, but there was nothing to hear,” he said. He added that he then became a witness to his own suffering as doctors and nurses tried to speak with him until they gave up all hope [The New York Times].

But is it really Houben doing the communication? Critics of “facilitated communication” like James Randi are howling about the coverage of the case, saying that FC has been debunked as a fraud for decades now. Psychologist Daniel Wegner, professor of psychology at Harvard University and a fellow of the American Association for the Advancement of Science has stated that facilitated communication is a striking example of the ideomotor effect, and tests of FC show that it is a complete fraud, farce, and delusion [James Randi Educational Foundation]. The debate over facilitated communication centers on whether the physically impaired patient is really contolling which letters are typed on a keyboard, or whether the “helper” who supports the patient’s hand is actually guiding it, in much the same way that a medium guides the marker on an Ouija board.

Related Content:
80beats: Vegetative Coma Patients Can Still Learn–a Tiny Bit
The Loom: Consciousness and the Culture Wars
DISCOVER: Vital Signs: Locked in Place
DISCOVER: Vital Signs, all our medical mysteries

Image: iStockphoto

Darwin Goes Digital for 150th Anniversary of “On the Origin of Species”

Andrew Moseman — Tue, 24 Nov 2009 15:09:35 +0000

Today’s the day—the 150th anniversary of the publication of Charles Darwin’s On the Origin of Species, the most famous work of the great 19th century naturalist. And to mark the occasion, the Darwin Manuscripts Project is uploading Darwin’s original drafts—10,000 pages worth—into an online archive. Look for the material to go online later today.

The collection includes 34 of the original 36 draft leaves of the book, according to editor David Kohn. “I’ve sat in the Cambridge University Library since 1974, touching these documents, but this is the first time that anyone can do this — online in this quantity and with this quality,” Kohn said [MSNBC]. The project leaders intend to digitize more manuscripts down the road, and also reconstruct Darwin’s library.

Still, there are missing pieces. English Heritage, which operates Darwin’s former home as a museum, launched a mission to recover a crucial Darwin notebook that’s been missing for the last two or three decades and might have been stolen from the house. According to Darwin’s great-great-grandson, the author Randal Keynes, the notebook contains notes and descriptions of animals from Darwin’s Galapagos visit. Says Keynes: “The Galapagos notebook is of outstanding value for the history of science…. If Darwin had not posed the questions in that notebook, he might never have written On the Origin of Species” [BBC News]. Luckily, English Heritage still has microfilm of the notebook created in 1969.

While one Darwin artifact is lost, another is found: A British family turned up a first edition of On the Origin of Species in an unexpected location. Christie’s auction house said Sunday the book – one of around 1,250 copies first printed in 1859 – had been on a toilet bookshelf at a family’s home in Oxford [AP]. Christie’s expects the book to fetch upwards of $100,000.

Image: Wiki Commons

DNA Scanner Proves That NYC Sushi Contains Endangered Bluefin Tuna

Andrew Moseman — Tue, 24 Nov 2009 12:00:33 +0000

Sushi lovers, we’ve got some bad news. For a study that came out in PLoS One, researchers ordered sushi at restaurants across New York City and Denver, Colorado, and found that an alarming percentage wasn’t made from the fish it was advertised to be. More than half of the eateries weren’t completely clear and honest about the fish they offered, the study says. Some even mistakenly served up escolar, which can give people diarrhea and stomach problems.

Although their results were shocking, exposing sloppy sushi joints wasn’t their main goal. The scientists were trying to improve on a new species-identification technique, called DNA barcoding…. Their goal is to build a catalog of every fish species on earth so that anyone with a handheld DNA reader could definitively identify fish within minutes [Wired.com].

One reason researchers investigated sushi is that so much of it has been made from endangered species like the bluefin tuna. In the restaurants that lead scientist George Amato checked out, the device showed 25 percent of what was labeled as tuna on sushi menus was bluefin, Amato said. The device also has been used to identify the presence of endangered whales in Asian markets and fraud in the labeling of caviar and red snapper [UPI].

This study comes in the wake of an international ruling that reduces the quota for bluefin catch from 22,000 metric tons annually to 13,500 for 2010. But that isn’t enough for many environmentalists, nor for The New York Times editorial board, which this weekend called for the United States to list bluefin under the Convention on International Trade in Endangered Species. The law effectively bars commercial trade in any listed species, and has been helpful in protecting other animals like elephants and whales [The New York Times].

Image: flickr / avixyz

Are Politics Skin-Deep? Liberal Voters See Obama as Lighter Skinned

Brett Israel — Mon, 23 Nov 2009 22:49:22 +0000

Researchers are making the case that a person’s political views cause them to see with a tinted perspective.

Scientists showed undergraduate students a series of digitally darkened or lightened photos of President Barack Obama last fall, and asked them which photos best represented him as a person. The results were striking: while self-described liberals tended to pick the digitally lightened photos of the president, self-described conservative students more frequently picked the darkened images. The more one agrees with a politician, in other words, the lighter his skin tone seems; the less you agree, the darker it becomes [Newsweek]. The study will be published in the Proceedings of the National Academy of Sciences.

According to lead researcher Eugene Caruso, they found that the degree to which someone saw a lightened photo as being representative of Obama was related to whether he voted for him a week later. That was true even after the researchers controlled for political views and measures of bias against blacks [NPR]. Caruso says their results indicate that the degree to which you see eye to eye with someone politically can alter your physical perception of them.

By controlling for bias against blacks, the study seems to indicate that race isn’t the issue, but simply how light or dark a person is, though it isn’t totally clear on that point. It also seems to buy in to the claim that Hillary Clinton artificially darkened an image of Obama, which wasn’t terribly widely believed. Anyway, the research’s most practical finding seems to be that devious political hacks don’t need to play games with candidates’ pictures because the voters are doing it themselves [Politico].

To see if their finding applied to politically ambiguous and unknown candidates, Caruso ran a similar experiment using altered photos of a fake candidate running for a board of education position. They also found that people shown darkened photos were less likely to say the would vote for the candidate, even if they agreed with them on roughly half of the issues. The researchers would like to see how the results of their Obama photo experiment would compare to a similar experiment with a conservative biracial candidate.

Related Content:
DISCOVER: Future Tech: facial recognition systems in airports
80beats: “Undecided” Voters Have Already Decided… They Just Don’t Know It
80beats: Where You Vote Could Influence How You Vote

Image: PNAS

Ravenous, Leaping Asian Carp Poised to Invade Great Lakes

Brett Israel — Mon, 23 Nov 2009 21:30:14 +0000

The Great Lakes are under threat from an Asian carp invasion that could wipe out fishing stocks, and with it, the lakes’ billion dollar fishery. On Friday, officials from the Army Corps of Engineers reported that genetic material from the carp had been found for the first time in a nearby river beyond an elaborate barrier system, which has cost millions of dollars and was meant to block their passage [The New York Times]. There is concern that if carp make it into Lake Michigan, they will gobble up the plankton that native fish feed on.

Officials also say that recreational boating may be affected–the carp can grow up to 4 feet long and weigh up to 100 pounds, and the massive fish will occasionally leap up and strike boaters. Since they were found to be moving up the Mississippi River in 2002, agencies have been trying everything they can think of to slow them down, including erecting the expensive electric barriers that cost around $9 million. The barriers work by sending low-voltage electric current through steel cables that are strung across the canal; this creates an electric field that’s uncomfortable for the fish and that’s supposed to prevent them from swimming across it.

No one has actually spotted any carp on the far side of the underwater electric fence, but new tests let scientists detect the DNA of fish in a river or lake without actually seeing them. Fish have to pee and poop, too, and epithelial cells sloughed off from their bodies showed that Asian carp were in the Chicago Sanitary and Ship canal last month above an electrical barrier that was supposed to keep them out of the Great Lakes [Detroit Free Press]. If the carp have indeed passed through the barrier, that means only a single lock, which regularly opens to allow ships to pass, separates the carp from the world’s largest freshwater reserve. The only non-threatening explanation for the DNA is that carp feces or eggs could have been carried across the barrier by ship and barge traffic. The carp DNA was found as close as eight miles south of Lake Michigan and one mile south of the last shipping lock.

Ironically, the fish were originally imported to help Southern fish farmers fight algae-filled ponds in the 1970s. By the 1990s, flooding had pushed them into the mighty Mississippi and they began swimming north. Joel Brammeier, acting president of the Alliance for the Great Lakes, said “this is an absolute emergency” [The New York Times], because if the carp move past the last lock, there will be no stopping them.

Brammeier is calling for the last lock to be closed and all shipping traffic into Lake Michigan to be halted. The U.S. Army Corps of Engineers said it and other agencies had met since Wednesday to consider the best course of action. Authorities will be sampling the channel to try to locate any loose carp [AP]. Since rivers and lakes are very different ecosystems, scientists can’t say for sure how well the carp would survive if they make it to the Great Lakes. But a worst case scenario has them spreading like a cancer–a doomsday scenario for a region already weakened by invasive species such as zebra mussels.

Image: U.S. Fish & Wildlife Service

New Take on Titan Hints at More Fuel for Potential Life

Andrew Moseman — Mon, 23 Nov 2009 18:35:15 +0000

With its thick atmosphere, chemical makeup, and an atmospheric pressure not too far from Earth’s, Titan is one of the most likely candidates for finding life elsewhere in our solar system. But at a temperature close to -300 degrees Fahrenheit, the surface of this Saturnian moon in anything but what we humans would call hospitable. Since this frigid place is far too cold for liquid water, any life there would need an alternative survival method. A new study published in Astrophysical Journal Letters suggests that the simple hydrocarbon acetylene, proposed as a possible energy source for life on Titan, could be much more abundant than scientists previously thought.

Titan has previously been shown to be dotted with lakes of liquid hydrocarbons, primarily methane and ethane. An estimate made in 1989 suggested bodies of liquid hydrocarbons on Titan would contain a few parts in 10,000 of acetylene. But an updated estimate based on data from the Cassini-Huygens mission to Saturn now suggests the lakes contain much more food for any hungry alien life-forms that might be present [New Scientist]. Lead researcher Daniel Cordier says the acetylene abundance could be as high as one part in 100, or 1 percent, of the surface lakes on Titan.

Back in 2005 another team proposed the idea of organisms in Titan’s lakes that could pull the acetylene from its atmosphere and combine it with hydrogen to produce energy. If the new estimates from Cordier’s team are correct, that food supply would be much larger than scientists initially believed. Researchers don’t know, however, how thoroughly the chemicals in those lakes mix—if they stay in separate layers, they may not be able to produce enough chemical reactions to power organisms.

This new analysis could raise other questions besides those regarding life. “Our results provide the chemical data needed to compute the amount of deposition of various hydrocarbons and nitriles in fluvial valleys in … Titan’s midlatitudes,” says the team [Technology Review]. In other words: Geologists, start your calculators.

Related Content:
DISCOVER: A Moon Full of Smust (Smust being the smog/dust combo that covers Titan)
DISCOVER: The Search For Aliens Gets Harder—But More Encouraging
80beats: New Evidence for Ice-Spewing Volcanoes on Saturn’s Moon Titan
80beats: Hydrocarbon Lake on Saturnian Moon May Be a Hotspot for Alien Life

Image: NASA

LHC Flings Protons Once Again; Scientists Celebrate With Caution

Andrew Moseman — Mon, 23 Nov 2009 15:15:00 +0000

Hackers. Leaking liquid helium caused by a faulty connection. International ridicule. And to top it all off, aerial attack by a wayward baguette. Yes, it’s safe to say that things haven’t gone according to plan at the Large Hadron Collider in the last 14 months, but the world’s largest particle smasher is finally—finally!—back online after its Friday restart, with proton beams circulating through this huge underground ring.

The first time protons circled the collider, on Sept. 10, 2008, the event was celebrated with Champagne and midnight pajama parties around the world. But the festivities were cut short a few days later when an electrical connection between a pair of the collider’s giant superconducting electromagnets vaporized [The New York Times].

The initial enthusiasm, it seems, was rather premature—scientists analysis of the failed connection revealed many more that probably couldn’t handle the strain of the energy needed to re-create conditions similar to the Big Bang. During 14 months of repairs dozens of giant superconducting magnets that accelerate particles at the speed of light had to be replaced [BBC News].

The long delay gave rise to frustration among scientists, ridicule by comedians, and time for the “LHC will destroy the world” theories to be replaced in the zeitgeist by the even loonier-sounding proposal that the LHC keeps malfunctioning because its potential future is canceling out its past. However, CERN scientists say, though they would have rather spent the last year-plus smashing particles together and hunting the Higgs Boson, analyzing their big machine has allowed them to understand it better than ever before.

Still, given the collider’s troubled history, CERN director of accelerators Steve Myers is taking it slow. If things continue to progress at this speed, scientists may be able to accelerate particles at the highest energy level ever tested before Christmas, although high-energy collisions that may shed light on the secrets of the universe would only happen in the new year, Myers said [Reuters].

Image: flickr/μμ

Osmosis De-Debunked? Sound Effects Cue Sleep Learning

Andrew Moseman — Mon, 23 Nov 2009 11:00:55 +0000

Amid mounting evidence that sleep is key for your memory, researchers published a paper in the journal Science last week suggesting that playing specific sounds while a person sleeps—sounds connected to something that the person is trying to memorize—could help the memory sink in.

The researchers taught people to move 50 pictures to their correct locations on a computer screen. Each picture was accompanied by a related sound — meow for a cat, whirring for a helicopter, for example [The New York Times]. Next the test subjects lay down for a nap, and while they slept the researchers played sounds relating to half the objects. When the subjects woke up, scientists tested them on how well they remembered where each object went. Participants didn’t know they’d been subjected to the sounds while they napped, but they fared better at placing the objects for which they heard sounds in their sleep than those they didn’t.

Lead researcher Ken Paller explains: “While asleep, people might process anything that happened during the day — what they ate for breakfast, television shows they watched, anything…. But we decided which memories our volunteers would activate, guiding them to rehearse some of the locations they had learned an hour earlier” [U.S. News & World Report].

Some scientists didn’t buy the sound-sleep connection. Neuroscientist Robert Vertes said the results showed “such a minor effect that it’s not significant,” adding that the effect was even less significant because other study subjects who remained awake showed similarly better recall with sound cues [The New York Times].

Still, the research team effused enthusiasm, saying the study suggests the sleeping brain is coachable, and sleepers could be coached to remember specific things they’ve already learned. However, it doesn’t provide evidence that those “learn a new language in your sleep” recordings do any good. So you might want to steer clear of them, lest you find yourself like Dexter the boy genius, repeating “omlette du fromage” all day.

Image: iStockphoto

Found: Dino-Munching Crocodiles Who Swam in the Sahara

Brett Israel — Fri, 20 Nov 2009 21:25:55 +0000

A thrilling set of ancient crocodile fossils have been unearthed in northern Africa. A “saber-toothed cat in armor” and a pancake-shaped predator are among the strange crocodile cousins whose bones have been found beneath the windswept dunes of the Sahara, archaeologists say [National Geographic News].

At a news conference organized by the National Geographic Society, which sponsored the research, scientists announced that the fossils represent 5 species; 3 new species and 2 that were previously known. These ancient croc ancestors, known as crocodilyforms, are unlike any crocodiles encountered in the Northern Hemisphere, according to the research team. Their findings are detailed in the journal ZooKeys.

The crocs were spectacularly diverse, and included a species that ate dinosaurs, two that grew up to 20 feet long, and two that had long legs for quick movement on land but also had long tails for swimming. The three new species are:

• BoarCroc (Kaprosuchus saharicus), a 20-foot meat-eater. It used its snout for ramming and three sets of dagger-shaped fangs for slicing dinosaurs it ate.

• PancakeCroc (Laganosuchus thaumastos): a 20-foot-long, squat fish-eater with a 3-foot long flat head with spike-shaped teeth.

• RatCroc (Araripesuchus rattoides), a 3-foot-long plant and grub eater with buckteeth used for digging [Chicago Sun-Times].

The two previously known species are nicknamed DuckCroc, a three-foot long, long-legged croc that feasted on fish and frogs, and DogCroc, another small and lanky croc that mostly ate plants and grubs.

“These species open a window on a croc world completely foreign to what was living on northern continents,” [researcher Paul] Sereno said of the unusual animals that lived 100 million years ago on the southern continent known as Gondwana [AP]. From the fossils, researchers believe that at least some of these crocs were equally at home on land and in the water. They roamed what is now Morocco and Niger at a time when the landscape was covered with lush plains and broad rivers. The crocs included meat eaters that could have devoured man—if any humans had existed at the time.

From studying the fossil skulls, the researchers made predictions about the crocs’ brain power. The scientists studied the animals’ brains by creating digital and physical casts from CT-scans, 3D X-rays. Both DogCroc and DuckCroc had broad, spade-shaped forebrains that looked different from those of living crocodiles [Telegraph]. Researcher Hans Larsson, who discovered the fossils of BoarCroc and PancakeCroc, said the brain models suggest these crocs had superior brain power compared to their modern ancestors, possibly because chasing after your meals on land requires more energy than milling around in the water waiting for your food to arrive.

Serano, the team leader, has a penchant for discovering the ancient crocs. He discovered SuperCroc—the largest of them all—nine years ago in the same region. His latest findings are the subject of “When Crocs Ate Dinosaurs,” which airs on the evening of Saturday, November 21, on the National Geographic Channel.

Image: Mike Hettwer, courtesy National Geographic

Ripped From the Journals: The Biggest Discoveries of the Week

Eliza Strickland — Fri, 20 Nov 2009 19:16:28 +0000

Proceedings of the National Academy of Sciences, November 17
When is a goat like a reptile? When it’s cold-blooded, slow-moving, and fond of sitting on warm rocks. Researchers have discovered a bizarre dwarf goat species that lived on the Spanish island Majorca, but that went extinct when human hunters arrived on the island about 3,000 years ago. The study says that the goat’s cold-blooded ways allowed it to survive on the resource-scarce island, as it could match its growth and metabolism to the available food supplies, but its sluggish movements made it easy prey for humans. In medical news, a research team investigating the dramatic failure of an HIV vaccine trial, in which vaccinated people seemed to be at higher risk of infection, has proposed a new theory for the failure. The study suggests that the common cold virus, which was used in the vaccine to carry HIV material around the body so the immune system could learn to recognize HIV, may have been at fault. The vaccine didn’t cause infection. But for people who have previously been exposed to this cold virus, its appearance may have triggered a gathering of immune cells called CD4 T-cells which were ready to fight it off. But those are the cells that HIV infects, so if people were then exposed to the HIV virus, the virus would have been presented with a ready availability of targets. Finally, an interesting study captured a snapshot of evolution-in-action on the Galapagos islands. A husband and wife team of evolutionary biologists is documenting what appears to be the emergence of a new species among Galapagos finches, the same birds that inspired Charles Darwin’s theory of evolution.

New England Journal of Medicine, November 19
Who can resist a story about brain-eaters that also has valuable medical and evolutionary lessons? A NEJM study describes a tribe in Papua New Guinea that used to engage in ritualistic cannibalism; when a member of the tribe died, the others ate the person’s brain as a mark of respect. The practice became a problem in the early 20th century, when some people became infected with a disease similar to mad cow disease and its human variant, Creutzfeldt Jakob disease. These fatal diseases are caused by misfolded proteins in the brain, so when the Fore people of Papua New Guinea consumed an affected brain the disease quickly spread. But a new study of living Fore people revealed that many are immune to the disease, which suggests that evolution has been acting quickly: Those people who had no resistance to the disease died off quickly, while people with resistance lived and multiplied. Researchers also hope to study the Fore people for clues on how to treat or prevent such diseases.

Science, November 20
A fascinating study brought new insight into the disappearance of North America’s prehistoric megafauna, via a study of a fungus present in their mega-dung. The fungus releases a spore that is preserved in sediment samples, which researchers can analyze to determine how prevalent the great beasts were throughout history. The new analysis suggests that megafauna like mastodons, mammoths, and sabre-toothed tigers began a slow decline around 15,000 years ago and vanished completely about 1,000 years later. This suggests that their extinction was not a result of an asteroid or comet that is thought to have exploded over North America much later. It also takes the blame off the Clovis people, who were thought to be North America’s first settlers, but who didn’t establish themselves until about 13,300 years ago. Some researchers have suggested that the Clovis people hunted mammoths and the like into extinction. While the new study makes a good argument, it’s unlikely to persuade all proponents of alternate theories–expect rebuttals to follow. Another study revealed the results of a four-year effort to map the genome of corn. The task turned out to be surprisingly complex, as the corn genome has 12,000 more genes than the human genome, but the resulting data has already helped scientists understand how maize was domesticated, and should help agricultural researchers increase the efficiency of corn crops.

Journal of the American Medical Association, November18
Upper-crust ancient Egyptians weren’t so different from modern Americans in one way: a new study that X-rayed 20 Egyptian mummies found signs of clogged arteries and heart disease in 16 of them. Since only the Egyptian elite were mummified, it’s impossible to say if cardiovascular problems were widespread in ancient Egypt. But the researchers note that the elite often dined on rich dishes such as beef, mutton, and cakes with honey and butter, and suggest that this fatty diet may have contributed to heart disease among the nobility.

Nature, November 19
In another warning bell regarding global warming, a study found that the world’s oceans are absorbing less globe-warming carbon dioxide than they used to. Until about the 1980s, researchers say, the absorption rate kept pace with increasing greenhouse gas emissions. But since then the intake rate has slowed, due to a gradual change in the oceans’ chemistry. The increased load of CO2 in the seawater is changing the pH balance of the oceans and making them more acidic, which then limits the amount of CO2 they can sop up. The results are troubling, because they indicate that even more greenhouse gases will remain in the atmosphere.

Star Trek-Style “Phaser” Paralyzes Worms With a UV Blast

Andrew Moseman — Fri, 20 Nov 2009 18:09:34 +0000

Feel like teaching a lesson to that pinhead-sized worm that’s been bothering you? According to a study in the Journal of the American Chemical Society, a material called dithienylethene plus a blast of UV light can stop a worm in the midst of its worming, rendering it temporarily paralyzed.

The researchers fed a light-sensitive material — a “photoswitch” known as dithienylethene — to the transparent worms. When exposed to ultraviolet rays, the molecule turned blue and the worms became paralyzed. Using visible light instead made the chemical turn colorless and the paralysis ended [LiveScience]. Scientists aren’t sure why the transparent nematodes became paralyzed, but they know dithienylethene changes shapes and suspect it interferes with the worm’s energy-producing metabolic pathways. Repeated cycles of UV-induced paralysis actually killed some of the worms.

Unsurprisingly, news of this worm stun-gun led to longing for Star Trek-style phasers, and the scientists, though skeptical, were good sports about it. As lead researcher Neil Branda said tactfully: “I’m not convinced there’s a legitimate use of turning organisms on and off in terms of paralysis, but until somebody tells me otherwise, I’m not going to say that there isn’t an application” [BBC News].

But while phasers remain a fantasy, light-activated materials certainly have a future in medical research. Light-activated drugs could be used to activate tumour-killing drugs once they reach a particular location in the body. Similar chemicals have been used before, but have required a steady supply of light – often harmful UV bandwidths – to stay active. The new compounds, known as diarylethenes, could be more useful because they can be switched on and off with a single light pulse, Branda says [New Scientist].

Image: Wiki Commons / Yonatanh

IBM’s Billion-Neuron Simulation Can Match a Cat’s Brainpower

Andrew Moseman — Fri, 20 Nov 2009 15:52:56 +0000

An artificial brain as powerful as a human’s remains a distant goal, but scientists are inching closer. This week IBM announced that by using a brain-simulating algorithm called BlueMatter, researchers created an artificial brain simulation that packs more brainpower than a cat.

Researchers used an IBM supercomputer at the Lawrence Livermore Lab to model the movement of data through a structure with 1 billion neurons and 10 trillion synapses, which allowed them to see how information “percolates” through a system that’s comparable to a feline cerebral cortex [San Jose Mercury News]. The team’s previous effort two years ago, modeled after a rat brain, simulated only about 55 million neurons.

The staggering surge in computing power has engineers like IBM’s Dharmendra Modha drooling over the possibilities for more brain-like computers. By reverse engineering [the] cortical structure, Modha says, researchers could give machines the ability to interpret biological senses such as sight, hearing and touch. And artificial machine brains could process, intelligently, senses that don’t currently exist in the natural world, such as radar and laser range-finding [Popular Mechanics].

It should come as no surprise that the design suggests such military applications, as DARPA provided much of the funding. But like the Internet and other technologies originally developed for the military, BlueMatter’s abilities could lead in a multitude of directions. “As our digital and physical worlds collide, there is a tsunami of information,” Modha said. “There is a need for a new kind of intelligence that can sort through, prioritize and extract the most important information, much like how the brain deals with sight, sounds, tastes, touch and smell” [San Jose Mercury News].

Image: IBM Almaden research lab, Stanford University

Spores in Mastodon Dung Suggest Humans Didn’t Kill Off Ancient Mammals

Brett Israel — Fri, 20 Nov 2009 12:00:53 +0000

A fungus found within ancient mammoth dung is providing scientists with clues about how the large ancient mammals collectively known as megafauna went extinct. The fungus, Sporormiella, produces spores in the dung of large herbivores. These are then preserved in the layers of mud and can provide an index of the number of these animals, or megafauna, that roamed the environment at a particular time [BBC News]. For a new study, researcher Jacquelyn Gill collected and analyzed spores in sediment samples from an Indiana lake and several sites in New York.

From Gill’s analysis, published in the journal Science, she concluded that North American megafauna began a slow decline around 15,000 years ago and vanished about 1,000 years later. The data suggests megafauna started going extinct much earlier than previously though, which basically wipes out two theories of their extinction.

There are several theories surrounding the extinction of North American megafuana, but there are a lot more questions than answers. Much of the uncertainty surrounding the extinction of the North American megafauna, which includes mastadons, saber-tooth tigers and giant ground sloths, is due to a scarcity of evidence and difficulty pinning down the timing of events. Several major events occurred around the same time the animals disappeared: Major environmental upheaval associated with the end of the Ice Age; an asteroid explosion over North America; and the arrival of man [Wired.com]. But the new data points to an extinction culprit other than an asteroid or comet impact, because the impact is believed to have occurred long after the megafauna began their decline.

If humans were responsible for the extinction, it would have to be settlers that came along before the Clovis people, which is another debate in itself. The Clovis culture is thought to have been the first civilization to take hold in North America around 13,300 years ago–after the bulk of the megafauna extinctions, according to the new analysis. But some researchers believe that earlier settlers walked the land before the Clovis people, and could have hunted the mastodons and mammoths. The new study adds crucial info to the fossil record, but it is likely to kindle, rather than quench, the debate over megafauna extinction.

Image: Barry Roal Carlsen, University of Wisconsin-Madison