Businessweek Archives

Earth's Post Seismic Stress


Developments to Watch

EARTH'S POST-SEISMIC STRESS

RESIDENTS OF AREAS prone to earthquakes would give a lot to know when and where the next one will hit. Scientists haven't had much luck predicting when quakes will strike, but a study published in the journal Science suggests that the likely locations of future quakes can be figured out by studying the epicenters of earlier ones.

Using a wealth of data gleaned from measurements made by lasers and satellite tracking systems, geophysicists from the University of California at Los Angeles have found that regions of highest stress were not on the major faults in California, as expected, but in the regions surrounding previous earthquakes. After a quake, says Li-yu Sung, an assistant researcher at UCLA and co-author of the report, the Earth's crust continues to deform as the energy trapped in the rocks is pushed deeper into the ground. "People don't observe these post-seismic effects," says Sung, "because there are no surface ruptures."

While the notion that past earthquakes disturb a larger area is not new, the researchers say they were "stunned" by the dominance of these post-seismic strains. By examining these areas more closely, the researchers say they could better understand the potential for a quake in a given area.EDITED BY CATHERINE ARNST Scott LaFeeReturn to top

SONGS THAT LEAD DOWN MEMORY LANE

ELDERLY SUFFERERS OF dementia and Alzheimer's disease may seem to have lost their memories. But the memories themselves are not gone: Doctors believe that it is the ability to retrieve them that is damaged. And music may be a cure. A study funded by the New York State Health Dept. and presented at a gerontology conference in Adelaide, Australia, found that dementia patients could recall long-term memories after hearing familiar tunes.

Forty elderly residents suffering from dementia at Beth Abraham Health Services, a New York nursing home, were randomly placed in a musical or verbal reminiscence group. They were encouraged to recall information when stimulated by theme-based music such as love songs, or to verbal suggestions, during 30-minute sessions held twice a week for 10 months. Music group participants, unlike those in the verbal group, showed significant improvement in memory recall and recognition and a marked decrease in agitation, says Concetta M. Tomaino, Beth Abraham's director of music therapy. The results show that "music therapy is a valuable tool to help enhance quality of life" for dementia patients, she says. Maybe listening to classic rock is actually good for the mind.EDITED BY CATHERINE ARNSTReturn to top

THREADS TO SNAG COUNTERFEITERS

IN THE LATE 1970S, SCIENTISTS AT OAK RIDGE NATIONAL Laboratory developed a technique for permanently marking paper or cash currency so it could be positively authenticated. It involved embedding in the paper a square-inch tag made of fluorescent nylon fibers of varying lengths and with different light-absorbing properties. The pattern of fibers in each tag is generated at random, and each one creates a unique optical signature when exposed to light. But Oak Ridge never found a commercial partner to develop the technology.

Last year, researchers showed their high-tech threads to Jay Fraser, president of Tracer Detection Technology Corp. in Syosset, N.Y., which is developing chemical tags for tracking narcotics and other contraband. Fraser licensed the fiber technology from Lockheed Martin Energy Research Corp., manager of the Oak Ridge lab. He hopes to embed tags in everything from compact disks and credit cards to designer clothes and accessories to help manufacturers fight counterfeiting.

First, Fraser hopes to enlist a large merchandiser to help develop an optical scanner that can read the patterns. Then, he says, customs agents or retailers will be able to verify goods by running the scanner over the fiber tag and matching the results with values stored on a tiny bar code or in a central database.EDITED BY CATHERINE ARNST Neil GrossReturn to top


American Apparel's Future
LIMITED-TIME OFFER SUBSCRIBE NOW

(enter your email)
(enter up to 5 email addresses, separated by commas)

Max 250 characters

 
blog comments powered by Disqus