Uncategorized
- Earth
Dust devils produce magnetic fields
Scientists who chase dust devils report that the tiny twisters can produce a small magnetic field that changes magnitude between 3 and 30 times per second.
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19174
I scuba dive, and I’ve noticed that when the current is brisk through some coral formations, small swirls behave exactly as dust devils. Would the researchers predict that any magnetic phenomena could be produced by silt in salt water? Lindsey Randal Potts San Antonio, Texas Probably not, says William M. Farrell of NASA. Any charges […]
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Essence of g
New efforts to probe the biology of intelligence stir up a long-running controversy over what mental tests actually measure.
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19214
Your article refers to “the current theory that high intelligence arises from the coating of brain cells with especially large amounts of the fatty substance called myelin.” As a person with multiple sclerosis, anything about myelin interests me greatly, yet I have never heard of this. Marion Leeds Carroll Arlington, Mass. For more, see Daniele […]
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Genghis Khan’s Legacy?
Genghis Kahn's military success 800 years ago may have spread a particular form of the Y chromosome, one he may have himself carried.
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- Health & Medicine
Stress-prone? Altering the diet may help
Tailoring a diet to fuel the brain with the precursor of a mood-enhancing chemical may help vulnerable individuals cope with stress.
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Mice can thank a hormone for the memories
Oxytocin, a hormone previously implicated in mammalian sexual and maternal behavior, may play a role in social recognition in mice.
- Chemistry
Lakes reveal low phosphate concentrations
Researchers using a new technique have found that previous measurements of phosphate, an important nutrient in lake ecosystems, have grossly overestimated its concentration.
- Animals
He and she cooperate on anti-aphrodisiacs
Scientists have for the first time identified a chemical that serves as a butterfly anti-aphrodisiac.
- Anthropology
Gene test probes Neandertal origins
A new DNA study supports the theory that Neandertals didn't contribute to the evolution of modern humans.
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19173
Erik Trinkaus argues that fossil evidence shows signs of considerable interbreeding of Neandertals and modern humans. However, I don’t believe that proves we could have Neandertal ancestors. Couldn’t crossbreeding result in sterile offspring, such as is seen in mules? Anne Wittke Flagstaff, Ariz. Sure. Trinkaus argues, however, that the presence of Neandertal traits on the […]
