Million Km

Superbug Cleans Up Cleaning up underground nuclear waste may entail the radiation-resistant bacterium Deinococcus radiodurans, capable of withstanding exposures of 6,000 rads per hour (1,000 will kill a person within days). Scientists revealed in the November 19,1999, issue of Science that they have sequenced the microbe's genome and unveiled some of its secrets for survival. Now researchers have engineered the bug to detoxify metal and organic wastes.The superbug was concocted by placing into the bacterium the genes required for breaking down toxic mercury and toluene.Success with this recombinant,reported in the January Nature Biotechnology, suggests that future strains can have varied pollution-fighting attributes. —Diane Martindale More "In Brief'on page 22

In Brief, continued from page 19 Moon Illusion Explained Lloyd Kaufman and his son James H. Kaufman, working at the IBM Almaden Research Center, have gathered concrete data to explain the ancient optical illusion that causes a full moon near the horizon to appear bigger than a moon seen overhead. By measuring viewers' perception of the distance to artificial moons projected onto the sky, the researchers showed that the "apparent distance" to the moon—rather than the real distance—determines its perceived size. When the moon is on the horizon, the brain picks up distance cues from the surrounding terrain and interprets the moon as being farther away.This,in turn, causes the brain to see a larger moon. (The new work opposes alternative explanations based on "apparent size.") The study appeared in the January 4 Proceedings of the National Academy of Sciences. —D.M.

Lou Gehrig's Virus? Providing the strongest evidence yet that infection is the cause,a French-U.S. collaboration has uncovered a virus associated with amyotrophic lateral sclerosis (ALS),or Lou Gehrig's disease.The researchers found that 15 of 17 people with the wasting condition harbored a virus similar to Echovirus-7, which causes meningitis and rare cases of enceph-alitis.In contrast,the virus appeared in only one of 29 people who died of causes other than ALS. How the virus infects the motor nerves of the spinal cord and whether it is actually responsible for ALS and not simply a bystander remain to be determined.The work appears in the January Neurology. —Philip Yam

Surrogate Cat

Playing surrogate mom in an effort to rescue the world's endangered small cats, Cayenne,a six-year-old domestic house-cat from New YorkCity,was implanted with the embryo of an African wildcat and subsequently gave birth to a healthy wild kitten named Jazz.The work,by Betsy Dresser of the Audubon Institute Center for Research of Endangered Species in New Orleans, is the first successful interspecies frozen-thawed embryo transfer (previous efforts used fresh embryos).Fu-ture breeding plans include bongo an-telopes,tigers and whooping cranes (see www.auduboninstitute.org). —D.M.

More "In Brief"on page 26

optimistic. Klaus Pinkau, co-chair of the ITER Working Group, reported that heated plasma has self-insulating properties that would facilitate the plasma burn. And other reactors have delivered promising results. By 1998, says Hideyuki Takatsu of the Japan Atomic Energy Research Institute (JAERI), "the JT-60U, the largest tokamak in Japan, achieved equivalent breakeven conditions." That is, if the JT-60U could use the energy-richer mixture of deuterium and tritium rather than just deuterium, it would have achieved breakeven. The Joint European Torus (JET) in the U.K. got close, delivering 16 megawatts from fusion while consuming about 25 megawatts.

Could turbulence undermine the cheaper ITER? Not likely, according to Carlos Alejaldre, director of the National Fusion Laboratory of Spain's center for energy and technology research (Ciemat). His team performs fine plasma diagnostics in Spain's TJ II Stellerator, and he concedes that turbulence leads to some uncertainty but that "simulations and experiments at JET and other machines have given us the confidence that ITER will achieve its goals." More problematic in the long run, Alejaldre thinks, are the energetic neutrons that would make the device radioactive. Without appropriate shielding, future commercial reactors might be uneconomical.

For ITER supporters, the immediate concerns remain political, such as agreeing on a country to host the reactor and getting sufficient funds. The withdrawal of the U.S. was, in their view, a political decision, and the lukewarm U.S. interest has more to do with the fact that the country has big oil and coal reserves. Japan considers the fusion option as a "kind of energy security for our country," Takatsu explains. "We have very limited energy resources."

European and Japanese agencies will decide their funding strategies in June, which could dictate how quickly ITER progresses. ITER could be built in 15 years and see results within 25. But it's clear that the U.S. withdrawal hurts. "We would be delighted if it would go forward," says Richard Hazeltine, head of the Institute of Fusion Studies at the University of Texas at Austin. If money comes in the next two years, he does not discount the possibility that the U.S. would consider a "renewed participation." — Luis Miguel Ariza in Munich

LUIS MIGUEL ARIZA is a freelance science writer based in Madrid.

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