Новости науки и техники в "Scientific American"

ALASKAN GLACIERS MELTING FASTER THAN PREVIOUSLY THOUGHT

Rising sea levels are bad news for residents of coastal communities and island nations. Precise predictions of future conditions in these areas are vital for policy formation, but scientists are not yet certain exactly why this phenomenon is occurring. To address the problem, researchers from around the world are working to quantify the contributions of various melting ice masses, but so far data have been skimpy, leaving conclusions drawn from them fraught with uncertainty. To that end, a new study conducted in Alaska presents a significantly more comprehensive analysis of the contribution of mountain glacial melting to rising seas. The findings are ominous: most glaciers have been thawing at an increasingly fast pace since the 1950s, and the Alaskan group has itself caused a significant increase in sea levels.

GENETIC ANALYSES HINT AT MORE HURDLES FOR ANTIMALARIALS

Despite attempts to foil malaria using insecticides and pharmaceuticals, the scourge still infects approximately 300 million people annually and kills as many as 2 million. Now new findings provide further insight into why the disease is so hard to control. Research indicates that the malarial parasite Plasmodium falciparum is older and more genetically diverse than previously thought. Moreover, it develops drug resistance surprisingly quickly.

NANOCRYSTALS COULD FORM BASIS OF ARTIFICIAL LEAVES

Atmospheric concentrations of the greenhouse gas carbon dioxide have increased dramatically over the past few decades. Plants can help lower these levels through photosynthesis, in which carbon dioxide is removed from the air and converted to harmless oxygen. Real vegetation requires light to perform this transformation, but recent work suggests that artificial leaves may one day facilitate this change - even in the dark.

DNA THROWS LIGHT ON ORIGINS OF DOMESTIC HORSES

The last sighting of a wild horse population occurred in 1969 in Mongolia. A far more common sight is a domestic horse, whether on a farm or a racetrack. DNA analyses are shedding light on how these magnificent beasts came to be controlled by humans. Modern horses, it seems, were domesticated from several distinct ancestral populations. And because horse domestication may have played a key role in the spread of some European languages, the findings could further the study of language evolution.

ELEMENT 118 DROPPED FROM PERIODIC TABLE

Scientists at Lawrence Berkeley National Laboratory (LBL) have formally retracted their claims for the discovery of the most massive chemical element. The synthesis of the "superheavy" element 118, comprising 118 protons and 175 neutrons, was announced in a 1999 paper in Physical Review Letters. The discovery appeared to confirm theories from the 1970s that predicted heightened stability for nuclei containing around 114 protons and 184 neutrons. But subsequent attempts to reproduce the results have failed.

ASK THE EXPERTS: ON AVERAGE, HOW MANY DEGREES APART IS ANY ONE PERSON IN THE WORLD FROM ANOTHER?

Duncan J. Watts, an associate professor of sociology at Columbia University and author of the forthcoming book Six Degrees: The Science of a Connected Age (Norton, 2003), explains.