23 апреля 2002 г.
|
Новости науки и техники в "Scientific American"
23 апреля 2002 г. |
X-RAY EVIDENCE SUGGESTS A NEW FORM OF MATTERBOOK OF THE MONTH: OUR POSTHUMAN FUTURE: CONSEQUENCES OF THE BIOTECHNOLOGY REVOLUTION By Francis FukuyamaRecent observations of two unusual stars have produced unexpected results, suggesting the existence of both a new form of matter and an exotic new type of star, scientists say. Previous research had led astronomers to believe that the objects were neutron stars--the extremely dense leftovers of supernova explosions. But according to the new results, one of them appears to be too small and the other, too cold. These inconsistencies, astronomers say, suggest that one or both of the stars could be composed of an odd combination of quarks, the tiny particles usually bound together inside protons and neutrons.COMMON WEED KILLER DISRUPTS FROG'S SEXUAL DEVELOPMENTExposure to less than one part per billion of the most commonly used herbicide in the U.S. can feminize male frogs, according to a new study. The findings suggest that concentrations of chemicals considered safe for humans can have insidious effects on amphibians and could be contributing to their decline.ARE ICY ROCKS WITH MOONS KEYS TO THE MYSTERY OF PLUTO?The Kuiper Belt is a rubble pile left over from the solar system's era of planet building some 4.5 billion years ago. It consists of a band of ancient bodies that surrounds the sun between the orbits of Neptune and Pluto, and possibly extending even farther out. Its inhabitants, known as Kuiper Belt Objects (KBOs), are made up of rock and ice. Recently, astronomers have observed KBOs with companions orbiting them--discoveries that may help shed new light on the debate over whether or not Pluto is a planet.In The End of History and the Last Man, Francis Fukuyama argued that history was over because the world was converging toward societies of democratic capitalism. The book's thesis, much disputed when it was first published as an article in 1989, seems all the more dubious in the wake of September 11. Now, in Our Posthuman Future, a volume likely to be similarly contested, he claims that biotechnology has brought about "the recommencement of history." By that he means that the biotechnological manipulation of human beings may well "move us into a 'posthuman' stage of history"--change human nature in ways that erode the foundations of the putative convergent political order.STUDY SUGGESTS PRIMATES AND DINOSAURS SHARED THE EARTHThe first primates may have scampered among the trees while dinosaurs still ruled the planet, according to the results of a new study. Researchers conclude that primates--the order of mammals to which humans belong--arose more than 15 million earlier than previously thought. In addition to posing difficulties for widely held ideas about the emergence of this group, the findings could force scholars to rethink the timing of the origin of humans.GROCERY DATA COULD WARN OF ANTHRAX OUTBREAKSSurges in grocery sales of over-the-counter drugs could alert officials to anthrax outbreaks. Currently, authorities rely on data from medical and public health sources to detect large-scale anthrax exposure. But a new study suggests that tracking the sales of such common medications as cough syrup might be more effective than traditional detection methods in revealing outbreaks early on and could therefore help reduce mortality in such cases.TECHBIZ CHANNEL: FACING YOUR GENETIC DESTINYFinding treatments that match individual gene profiles is the next frontier in drug research and the objective of a new science called pharmacogenomics. Virtually every major pharmaceutical company is now investing millions in its pursuit.ASK THE EXPERTS: HOW CAN YOU LIVE WITHOUT ONE OF YOUR KIDNEYS?Mark A.W. Andrews, associate professor of physiology at the Lake Erie College of Osteopathic Medicine, explains.