More Stories from the October 28, 2000 issue
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It’s a boy! It’s a girl! It’s a mosaic embryo
Using a new technique to examine chromosomes of in vitro fertilization (IVF) embryos at the time they're implanted in the womb, researchers report abnormalities never seen later in development, possibly explaining why IVF has a low efficiency.
- Health & Medicine
Study bolsters head injury, Alzheimer’s link
Veterans who suffered a moderate or severe concussion during World War II face a heightened risk of Alzheimer's disease when they reach old age.
- Astronomy
Are most extrasolar planets hefty imposters?
A new study makes the startling claim that nearly half the objects reported to be extrasolar planets are something much more massive and mundane—either lightweight stars or stellar wannabes known as brown dwarfs.
- Animals
Dull birds and bright ones beat so-so guys
The plumage of yearling male lazuli buntings shows signs of a rare form of evolutionary pressure called disruptive selection.
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Nicotine metabolism may spawn carcinogen
The body may metabolize nicotine into products that the lungs subsequently may convert into a potent compound that causes lung cancer.
- Materials Science
Crystal puts pressure on diamonds
A new type of synthetic crystal called moissanite allows researchers to study more material at high pressure than is possible with traditional diamond devices.
- Tech
Aircraft trick may give big rigs a gentle lift
Using sheet-like jets of air to control aerodynamic drag and lift—a technology first developed for aircraft—may boost gas mileage and improve braking and handling of tractor-trailer trucks.
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Certain mental ills may be tied to violence
A long-term study in New Zealand links elevated violence rates in young adults to the presence of at least one of three psychiatric ailments—alcohol dependence, marijuana dependence, and a range of psychotic experiences and beliefs called schizophrenia-spectrum disorder.
- Archaeology
Early farmers crop up in Jordan
An ancient site discovered in southern Jordan dating back more than 9,000 years may help to illuminate the origins of farming in the Middle East.
- Archaeology
Agriculture’s roots go tropical
Tropical-forest dwellers in Central America may have cultivated manioc and other root crops as many as 7,000 years ago.
- Health & Medicine
Interferon delays multiple sclerosis
In some people who show early-warning signs of multiple sclerosis, the drug interferon-beta-1a seems to delay or even prevent the disease from becoming full-blown.
- Health & Medicine
Pill boosts cancer risk in some women
Women who took oral contraceptives before 1975, and whose mother or sister had breast cancer between 1944 and 1952, have triple the likelihood of getting breast cancer as compared with similar women who didn't take the pill.
- Health & Medicine
Gene helps alcohol help the heart
A genetic study indicates that moderate consumption of alcohol helps keep the heart healthy.
- Health & Medicine
Fetal cells pop up in mom’s thyroid
A woman's thyroid gland contains male cells, suggesting that cells from her son passed into her when he was a fetus.
- Paleontology
Listening to fish for extinction clues
Tiny fossils from fish that survived worldwide extinctions about 34 million years ago may reveal that cooler winters caused the die-off.
- Earth
A slump or a slide? Density decides
Using a full-scale simulator, researchers showed that just a small difference in soil density determines whether a landslide becomes a fast-moving killer or merely one that slowly slumps downhill.
- Materials Science
Scientists tone down silicon rockers
Researchers have created pairs of silicon atoms that stay level instead of slowly rocking in place, permitting scientists to study silicon-surface reactions in unprecedented detail.
- Materials Science
High-temperature ceramics takes flight
A recent NASA flight test of ultrahigh-temperature ceramic materials might lead to a new aerospace design that would make the space shuttle look downright old-fashioned.
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Culture of the Sea
Whales and dolphins strut their social stuff for scientists.
