Random Samples

Science  22 Feb 2008:
Vol. 319, Issue 5866, pp. 1019

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    NASA's Gamma-ray Large Area Space Telescope (GLAST) may be scientists' best hope for studying gamma-ray bursts throughout the universe. But the name doesn't exactly roll off the tongue. So NASA is asking the public to come up with something better.

    The $690 million observatory will aid researchers studying gamma-ray bursts—brief, intense flashes of light as bright as a million trillion suns. The bursts are thought to be linked to many celestial phenomena, including supernovae and black holes.

    GLAST, scheduled for a May launch, is a follow-up to NASA's Compton Gamma Ray Observatory, which was operational from 1991 to 2000. NASA officials say the new observatory possesses a stronger sensitivity to gamma rays and a wider view of the universe than its predecessor.

    The deadline to submit names is 31 March, and the winning name will be announced once the observatory is in orbit and all systems are tested. To suggest a name, visit the NASA Web site at glast.sonoma.edu/glastname/.


    You may already be a part of Ken and Barbie's plastic family. A new U.S. government study suggests that the bodies of most Americans are laced with bisphenol A (BPA), the primary component of one of the most widely used plastics.

    BPA is an ingredient in polycarbonate plastics, used in everything from baby bottles to composite dental fillings to toy dolls. Frequent use and heating can cause the plastic to break down, leaching BPA into whatever the plastic touches, including food. Although recent studies have linked BPA to reproductive problems in lab animals, little is known about humans and BPA.

    To measure BPA exposure, chemist Antonia Calafat and colleagues at the U.S. Centers for Disease Control and Prevention in Atlanta, Georgia, examined urine samples from 2517 participants in the ongoing National Health and Nutrition Examination Survey. Significant levels of BPA were present in 92% of the samples. Those with the highest levels were children and adolescents, women, and low-income participants.

    The body metabolizes BPA in only a few hours, suggesting that exposure to BPA is continuous, says epidemiologist Russ Hauser of Harvard School of Public Health in Boston. Although the jury's still out on what high exposures mean for human health, Hauser says industry should consider alternatives that aren't biologically active.


    Dissecting a formalin-soaked frog isn't part of most middle-school science curricula anymore. But a new software program promises to keep the sense of discovery—and the frog—alive. The virtual-reality program, called V-Frog, allows students to dissect internal organs, explore tissues using an endoscope, and even observe a beating heart—all with the click of a mouse.


    Computer-based multimedia dissections aren't new, as schools seek to avoid the use of chemicals and sharp objects as well as the controversy over the use of animals. But most programs are not interactive and offer only a few predetermined options.

    The new program was developed by computer scientist Kevin Chugh at Tactus Technologies near Buffalo, New York. Based on photographs and artistic renderings, V-Frog runs on a standard Windows-based personal computer. Using interactive and 3D technology, students can manipulate tissues so that each dissection is different. “It's intuitive for them,” he says. “It's the teachers who need the manual.”

    Jayne Mackta, president of the New Jersey Association for Biomedical Research in Union, says that virtual frogs enhance the learning experience but don't duplicate traditional dissections. “Do they completely eliminate the need for a real-model organism? I'd like to think no.”


    Christopher Columbus may not have brought the epidemic typhus that ravaged the New World after his arrival. In fact, the parasites may predate him by tens of thousands of years, according to a new study.

    Typhus, a potentially deadly flulike disease, is spread by body lice. David Reed, an evolutionary biologist at the Florida Museum of Natural History in Gainesville, and Didier Raoult of the University of the Mediterranean in Marseille, France, sequenced DNA from ancient lice preserved in the scalps and braids of 1000-year-old Peruvian mummies. To their surprise, the researchers discovered that the lice belong to a subtype found all over the world.


    Although this subtype typically infests the head, it also includes body lice, which thrive in clothing and spread diseases such as epidemic typhus. Thus, “it's reasonable to believe that body lice were in the New World” well before Columbus, says Dale Clayton, an evolutionary biologist at the University of Utah, Salt Lake City.

    Deciphering ancient DNA isn't new; researchers have sequenced DNA from extinct mammoths and Neandertals. But DNA in lice tends to degrade quickly, and the oldest lice genetic material sequenced to date comes from Napoleon's soldiers—bodies buried 200 years ago. With this new study, “it's as though a parasitologist or epidemiologist traveled 1000 years back in time to sample a parasite from a human patient,” says Mark Hafner of Louisiana State University in Baton Rouge.