Новости науки и техники в "Scientific American" 10 июня 2003 г.

UNTANGLING THE ROOTS OF CANCER

Most cancer researchers have long focused on mutations to a relatively small set of cancer-related genes as the decisive events in the transformation of healthy cells to malignant tumors. Recently, however, other theories have emerged to challenge this view. One hypothesizes that a breakdown in DNA duplication or repair leads to many thousands of random mutations in cells. Another suggests that damage to a few "master" genes mangles the chromosomes, which then become dangerous. A third challenger proposes that abnormal numbers of chromosomes in a cell may be the first milestone on the road to cancer.

GECKO-INSPIRED ADHESIVE STICKS IT TO TRADITIONAL TAPE

Move over, Spider-Man, soon the rest of us may be able to scale walls and cling to ceilings too. Researchers have developed a super-sticky adhesive modeled on the gecko foot that grips even the slipperiest surfaces.

BOOKSTORE:  PREHISTORIC ART: THE SYMBOLIC JOURNEY OF HUMANKIND by Randall White

About 40,000 years ago the first Homo sapiens - the Cro-Magnons - began to trickle into Europe, displacing the resident Neanderthals in the process. The contrast between the records of their lives that these very different hominids left behind could hardly be more striking. For no extinct human species, not even the large-brained Homo neanderthalensis, has bequeathed us evidence of a complex symbolic existence, based on the extraordinary cognitive capacities that distinguish us from all other living species today. In contrast, the lives of the Cro-Magnons were drenched in symbolism.

VOCAL LEARNING SIMILAR IN HUMANS, BIRDS

A baby songbird doesn't emerge from the egg singing perfectly. It starts out babbling, and gradually refines its tune over time. Human infants follow a similar developmental path when learning to talk. Scientists have thus often compared the acquisition of human speech to that of birdsong. But whether the mechanisms of vocal development are the same in humans and birds is a question few studies have tackled. To that end, new research suggests that babbling human babies respond to social cues from their mothers in much the way that avian babies do.

SATURN'S WINDS SLOWING DOWN

It seems things are settling down on Saturn, at least when it comes to the weather. Saturn has a reputation for being windy, with broad swaths of gales encircling the planet and traveling in alternating directions. But new findings indicate that the speeds of winds on the gas giant have decreased by 42 percent over the last two decades.

EQUINE CLONING HURDLES CLEARED, BIRTH OF COPIED MULE SUGGESTS

Starting with Dolly the sheep, scientists have successfully duplicated pigs, cows, cats, rabbits and rodents. The cloning of horses and other equids eluded them, however, despite numerous attempts. Now a mule named Idaho Gem is the first equine to join the cloned menagerie. Born on May 4, this foal is also the first sterile animal to be cloned.

ASK THE EXPERTS: HOW WERE THE SPEED OF SOUND AND THE SPEED OF LIGHT DETERMINED AND MEASURED?

Chris Oates, a physicist in the Time and Frequency Division of the National Institute of Standards and Technology, explains.