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    Cat Craze



    Do cats make you crazy? This was the question posed at last week’s Science on Tap, a monthly science café held at the Philadelphia bar National Mechanics. By the end of the talk, the answer was clear. “Probably not, but you should still be careful.”

    The world’s felines have something in common, a trait shared by both domestic housecats and lions in the African savannah: they carry the parasite Toxoplasma gondii, a highly infectious protozoan that can spread to most warm-blooded mammals, including humans.

    Keep reading

    Check out Sam Kean’s article about Toxoplasma gondii in the latest issue of Distillations.

    This monochrome liquor advertisement is a distant ancestor of the screens found in most of today’s televisions, cell phones, and laptops. These devices use compounds called liquid crystals to modulate light, a technology essential to the creation of thin electronic displays. This artifact from the early 1970s represents one of the first attempts to transform the liquid crystal display (LCD) into a commercially useful technology. In a sense it is less a picture frame than a window into the history of electronic innovation.

    Find more about the early days of LCD technology in the latest issue of Distillations.

    A Family Portrait of the Solar System


    Shortly before 8 a.m. on Tuesday morning, NASA’s New Horizons mission reached Pluto. Nearly nine-and-a-half years after its launch from Cape Canaveral, the nuclear-powered space probe captured the first high-resolution images of the outer solar system’s most famous celestial body. Rather than a blurry dot in a telescope, astronomers now see a geologically active world with a distinct heart-shaped region, named the Tombaugh Regio in honor of Pluto’s discoverer.

    To celebrate this milestone of space exploration, CHF research fellow Ben Gross compiled a “Family Portrait,” featuring Pluto alongside the eight planets recognized by the International Astronomical Union. This image—showing the solar system as it was understood throughout most of the 20th century—attracted a great deal of attention on social media and has since been featured in a Business Insider article and the popular science website IFLScience.

    Now you can download a high-resolution copy of “Family Portrait” for use as wallpaper on your laptop, tablet, or desktop computer:

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    Research based on identical twins separated at birth often raises uncomfortable questions about how much of human identity is shaped by DNA. Some twins end up marrying partners with the same first name. Others vote for the same political party, watch the same amount of TV, and smoke the same brand of cigarettes. Heredity appears to beat out environment most of the time.

    But what if instead of two twins being separated at birth, a nurse in a hospital mistakenly swapped one brother in a set of identical twins for another brother in a completely different set of identical twins? This actually happened to Jorge, Carlos, William, and Wilber in Bogotá, Columbia, in 1988. Their story was covered in the New York Times Magazine earlier this month.

    One set went to the country, and the other went to the city. Growing up, their parents assumed they were fraternal twins. By a stroke of luck, a mutual friend noticed their similarities and reunited them after more than 20 years.

    Surprisingly, researchers studying the twins found that the boys’ traits were affected roughly equally by the environment in which they were raised as by their genes, a phenomenon scientists call epigenetics. Basically, scientists believe certain genes switch on or off depending on environmental stimuli. Identical twins share 100% of their DNA, but their genes can be expressed differently depending on their experiences. This was evidenced by the fact that the twins who grew up in the city were taller than their country counterparts. They also had very different voices, speech patterns, and personalities.

    Check out the article for an expertly written story that weaves together genetics, technology, and identity.

    Image: A cross-section of a pregnant uterus containing twins. (Wellcome Image Library)

    Distillations Podcast Turns 200

    This is Distillations’s 200th episode, and we’re celebrating! We pored through hundreds of shows and pieced together some of the funniest, grossest, and most surprising moments in Distillations history.

    Still chuckling from episode 166, “Alchemy After Dark,” where CHF’s rare book curator Jim Voelkel cries from laughter while reading a steamy alchemical passage from yesteryear? Still trying to forget the body-cheese experiment from episode 156, “Hard to Stomach”? Or maybe you’re still perplexed about how a Viagra tablet might wind up in your herbal supplement, as explained in episode 197, “Fads and Faith”?

    We visit these moments and many more. Thanks for listening, and we hope you’ll join us for the next 200 shows!

    By Mariel Carr


    The mighty Tremoctopus. Behold!

    And here’s some folks reacting to the blanket octopus (on what appears to be a Japanese game show?):

    Here’s a strange thing that actually exists. Check out the latest issue of Distillations magazine for the history of even stranger creatures you can believe or not.

    What’s sweet and what’s non-fattening are usually different things, but in 1878 a chemist accidentally discovered a way to have both. Constantin Fahlberg was eating dinner after an exhausting day in the lab when he noticed that his bread tasted sweeter than usual. Tracing the source of the sweetness to his fingers, he returned to the lab to sample every vial and dish until he matched the taste with a beaker of benzoic sulfinide. While Fahlberg’s method was neither advisable nor safe, it did lead to the discovery of an artificial substance 300 times sweeter than sugar. He named it saccharin.

    Throughout the next century, more artificial sweeteners were developed, including the highly controversial aspartame. In 1965 James M. Schlatter was trying to synthesize an anti-ulcer drug when he licked his finger, accidentally discovering aspartame in the process. Artificial sweeteners allowed companies to produce products that are sweet, like diet soda, but without the calories associated with sugar.

    Saccharin and aspartame are both viewed with distrust by segments of the public, even though both substances are approved by the FDA. In the 1970s animal studies linked saccharin to cancer in rats. Today, scientists recognize that saccharin poses no health risks in small quantities.

    Aspartame is supposedly dangerous for a different reason; when digested, it breaks down into formaldehyde, a known carcinogen. Formaldehyde occurs naturally in all kinds of foods and in small amounts helps the body produce amino acids and other beneficial molecules. And, according to the CDC, plants and animals, including us humans, naturally produce small amounts of the carcinogen. As the video above points out, there is five times as much formaldehyde in 12 ounces of juice as there is in a 12 ounce can of artificially sweetened soda.

    If you’re looking for a slightly healthier way to enjoy sweet foods, artificial sweeteners won’t hurt you. Just don’t follow the examples of Fahlberg and Schlatter; an unknown chemical in a laboratory is unlikely to be sweet and delicious.

    By Jacob Roberts

    Video: Is Aspartame Safe? produced by the American Chemical Society.

    A Lunch Out of this World

    At a recent convention lunch I got an astronomical surprise. BIO, the organizer, does things big. These lunches have about 3,000 attendees and are meticulously scheduled. I’ve seen The Schedule firsthand, and it’s a work of organizational mastery. So when a speaker announced he’d have to return later with the rest of his scheduled remarks, I raised an eyebrow. They’re deviating from The Schedule. Something is happening.

    Greg Johnson, former astronaut, took the stage. “How fun! An astronaut!” I thought. NASA had a booth this year and idly I wondered if Johnson would be there later. His words brought me back to earth: We’re about to connect via satellite to the International Space Station, he told us.

    People murmured. Eyes widened. The video screens changed to show the communications room in Houston, where two NASA employees sat at a bank of computers. Their voices echoed through our Philadelphia hall as they connected us to Scott Kelly, currently in orbit on the International Space Station.

    Johnson and Kelly spoke about the experiments going on ISS, and why science is so important. The audience sat spellbound. At the end Kelly said farewell, slid his feet out from whatever had been keeping him upright, and did a zero-g flip for us.

    What can I say? It was out of this world.

    Sarah Reisert

    Image: Bio 2015. Keynote With Eric Topol.

    The greatest catastrophic environmentalist of all was Richard Nixon.

    Historian Jacob Hamblin made this provocative claim while recording the latest Distillations podcast. While Nixon is remembered for a corrupt administration and for political and military blunders during the Vietnam War, Hamblin wanted to remind listeners that as president Nixon passed a surprising amount of environmental legislation. He created the Environmental Protection Agency in 1970, passed the Marine Mammal Protection Act of 1972, signed the Endangered Species Act of 1973, proposed the Safe Drinking Water Act of 1974, and even tried to turn NATO into an environmental organization.

    Why would Nixon push NATO, an intergovernmental military alliance, to protect the environment? According to Hamblin, Nixon wanted to use global environmental issues to open up communications with the Soviet Union and so ease tensions during the Cold War. He saw large-scale environmental issues as foreign policy opportunities. For example, acid rain caused by coal-burning power plants in the United States made some lakes in Canada uninhabitable for fish. That problem could only be solved with international collaboration. Unfortunately for Nixon, the world was more interested in talking about the use of herbicides, like Agent Orange, by the United States in Vietnam.

    Nixon’s plan backfired when his own allies in NATO rejected it. Many European countries viewed environmental issues as local rather than global problems and were skeptical that a military alliance was an appropriate venue for environmental problem solving.

    Nixon’s motivation to protect the environment was not entirely pure: endorsing environmental legislation would earn him votes and distract the public from the Vietnam War. He believed in the power of environmentalism as a tool, but not as an ideology. His true beliefs were caught on tape in the Oval Office in 1971. In a private meeting with the president and chairman of Ford Motor Company, Nixon said that it would be impossible to eliminate all pollution unless everyone wanted to “go back and live like a bunch of damned animals.”

    Nixon’s ideas about global environmentalism proved to be prescient. Over the past few decades it has become abundantly clear that climate and politics are intertwined on an international scale. Drought in the Middle East helped spark the ongoing Syrian disaster, which has driven nine million from their homes, some to neighboring countries and some as far as to Europe.

    By Jacob Roberts

    Image: Richard Nixon walking on the beach at San Clemente, California in 1971. (Wikimedia Commons)

    In the late 1970s after the end of the Vietnam War, many Vietnamese and Laotian people began noticing that a sticky yellow liquid periodically rained down from otherwise sunny skies. Witnesses claimed the strange substance killed plants and sickened people.

    One ethnic group seemed especially affected by the substance: the Hmong, who had fought with France against Communists in Southeast Asia since the 1950s in the sparsely developed mountains in northern Vietnam and Laos. The CIA later recruited and mobilized Hmong soldiers, making them the target of sectarian violence when U.S. troops left the region. The newly empowered Communist regimes attacked the remaining Hmong, forcing them to flee to refugee camps in Thailand or face labor and reeducation camps in their home countries.

    After a lengthy investigation U.S. analysts concluded in 1981 that the substance, dubbed “yellow rain,” was a chemical weapon made of fungus toxins and created by the Soviet Union. The U.S. secretary of state at the time, Alexander Haig, Jr., announced that the Soviet Union gave the weapon to the Viet Cong and Pathet Lao, who dropped it on the Hmong (and other ethnic groups) in their villages and while they fled to refugee camps.

    If the Soviet Union was really stockpiling and distributing chemical and biological weapons, it would have been breaking a century of international laws and treaties. The Soviets denied the accusations vehemently and soon found an unlikely ally:  Matt Meselson, a Harvard University biologist.

    Meselson was skeptical of the claims made by Haig and in 1983 acquired samples of yellow rain from government officials in order to analyze them at Cambridge. Meselson found that the substance included large amounts of hollowed-out pollen indigenous to Southeast Asia. This alone made Haig’s claims seem dubious: pollen would be an extremely ineffective dispersal method for poison. Meselson’s team realized the pollen was the same pollen eaten by giant Asian honey bees, which digest the protein inside pollen grains but not the outer shell, hollowing it out. Furthermore the team found that the concentration of mycotoxins was not significantly greater in samples of yellow rain–covered leaves than on plants anywhere else in Southeast Asia.

    If U.S. officials were correct, the Soviet Union would be importing tons of predigested pollen from Southeast Asia, only to turn around and send that same pollen back as a difficult-to-disperse chemical weapon. Meselson proposed a simpler explanation: yellow rain was no weapon at all—it was harmless bee feces. The health problems being reported were the result of poor sanitation and lack of food among people being bombed and raided by Communist soldiers. It’s still a sore subject among the Hmong, but Meselson theorized that the connection between yellow rain and sickness was part hyperbole, part imagination.

    After reviewing the original study done by U.S. investigators, Meselson’s team found inconsistencies and contradictions in the testimony of people who witnessed yellow rain. The liquid sometimes rained down when there wasn’t a plane in sight. Most of the health problems could be explained by dysentery and nutritional deficiencies in refugee camps. It also became clear that the original interviewers had asked leading questions and unconsciously manipulated testimonies.

    Meselson’s findings were initially met with skepticism by other scientists and the U.S. government. It would take thousands of bees to make enough waste to look like rain. Why would so many bees be in such specific locations and why would they be pooping at the same time?

    In 1989 a Canadian biologist teamed up with a Malaysian scientist to solve the puzzle. The most revealing detail of yellow rain was when it tended to fall: hot, sunny days. The scientists measured the body mass of hundreds of bees before they left their hives and after they came back, finding that the insects lost 20% of their weight on the return flight. The bees would usually leave together in a giant swarm, defecate, and come back to care for their larvae. The scientists confirmed that the phenomenon occurred most frequently on hot days.

    Why were they excreting more on hot days? Asian honey bee larvae are sensitive to high temperatures and become deformed if they overheat.  The adult bees needed to reduce their mass so they could keep their larvae cool inside the hive. This and later research led to the general acceptance of Meselson’s explanation, although the U.S. government never retracted the original accusations against the Soviet Union.

    By Jacob Roberts

    Image: A 1678 plate depicting a beekeeper’s hive from Vinetum britannicum by John Worlidge. (Othmer Library)

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