DIVERSE VIRUSES SHARE FUNCTIONAL TRAITS
Researchers at the Howard Hughes Medical Institute at the University of Wisconsin-Madison say viruses as diverse as AIDS, the common cold and hepatitis share functional traits that suggest they all evolved from a common ancestor. The discovery, reported in the journal Molecular Cell, unexpectedly unites half of virology, linking large groups of viruses long thought to be functionally and evolutionarily distinct. The finding could speed the search for vaccines and treatments for a wide range of virus-related ailments that plague both people and animals. "Recognition of these links means that principles learned from a variety of virus systems now can be used to illuminate many others, allowing integration and generalization of knowledge across a wide range of important pathogens," says Paul Ahlquist, the study author. The finding is a surprise because many of the viruses responsible for these illnesses were thought to reproduce in ways so different from one another biologically that they were long believed to be unrelated.
NEW DETECTOR SENSES MISSING NITROGEN OXIDE
Nitrogen oxides, collectively known as NOx compounds, react with hydrocarbons to form a variety of nitrogen-containing pollutants, including nitric acid, one of the causes of acid rain. However, as much as half the resulting nitrogen oxide has been unaccounted for in the atmosphere, leaving air pollution models incomplete. Chemists at the University of California at Berkeley, think they have found the missing nitrogen oxides with the aid of the most sensitive detector of nitrogen dioxide in the world. Deploying the detector in downtown Houston and in a remote Sierra Nevada forest, the California researchers detected large amounts of organic nitrogen oxide compounds, alkyl nitrates, that were thought to be only a minor constituent of smog. In the forest, these alkyl nitrates included chemicals such as isoprene nitrate, which could only come from combining hydrocarbons emitted by trees, with tailpipe emissions of NOx, presumably from the city of Sacramento, which is upwind of the forest. In Houston, other alkyl nitrates are formed by combining NOx with industrial hydrocarbon chemicals. This is another instance of how man-made NOx compounds react with natural hydrocarbons from vegetation to produce ozone smog, affecting not only human health but influencing global climate change.
NUKED PORCELAIN PROVIDES INSIGHT INTO EXPOSURE LIMITS
Scientists, still studying the after-effects caused by an atomic bomb dropped on Hiroshima on Aug. 6, 1945, are calculating the amount of neutron fluence -- the number of neutrons from the blast found per square centimeter. According to researchers at Union College in Schenectady, N.Y., and two radiation institutes in Japan, the standards for a safe level of exposure to humans might be too conservative. Analyzing neutron-induced fission tracks on porcelain objects found in Hiroshima helps the scientists to calibrate the nuclear fluence. "These fission events occurred when thermal neutrons from the bomb caused fission in the normal trace amounts of uranium in the material," says Jonathan MacDonald, a research team member. One sample nearly matches the previous estimates, but the other one is 2 to 2.5 times higher, researchers say. MacDonald reported the new values at a recent Geological Society of America meeting. "If correct, the latter value may be important for regulation of human exposures in the United States, because many of the current regulations are based on theoretical calculated values," says MacDonald.
CHINA ONE STEP CLOSER TO A MAN IN SPACE
China has launched a dummy astronaut into space aboard a Shenzhou spacecraft, according to the official Chinese news service Xinhua, New Scientist reports. The launch puts China a step close to putting a real astronaut in space. Xinhua says that the spacecraft was launched from the Jiuquan Space Launch Centre in Gansu Province, northwest China. The report states that the spacecraft has "functions identical to a manned craft" and that "the spaceship's movement and gesture remained normal" during takeoff. The capsule was carried by a Long March 2-F booster rocket, which reportedly also carried a Chinese satellite into orbit. New Scientist also says the Hong Kong newspaper Wen Wei Po reports that the Shenzhou spacecraft is fitted with an imitation astronaut. The paper says the "human model" has been fitted with sensors designed to record the physical stresses that would be placed on a human astronaut. China has already performed a test flight involving animals.
(EDITOR: For more information about VIRUSES, call (608) 263-5916; about PORCELAIN, call (303) 357-1056.)