Uncategorized

  1. Blood cues sex choice for parasites

    Malaria parasites shift their female-biased production of offspring toward a more evenly balanced sex ratio as an infection proceeds.

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  2. 19010

    This article describes the myelin sheath as “made of protein.” However, Merriam-Webster’s Collegiate Dictionary (online) provides the following definition of myelin: “a soft white somewhat fatty material …” (emphasis added). Ann M. ThrockmortonLa Mesa, Calif. That’s right. There was an oversimplification in the story. Myelin is made up mostly of lipids .–D. Christensen

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  3. Health & Medicine

    Learning from leprosy’s nerve damage

    The bacterium that causes leprosy directly damages a protective sheathing around many nerve cells.

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  4. Ecosystems

    Famine reveals incredible shrinking iguanas

    Marine iguanas in the Galápagos Islands are the first vertebrates known to reduce their size during a food shortage and then regrow to their original body lengths.

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  5. 19009

    I am puzzled at the great concern over the problem of mercury thermometers, as noted in this article. I grant that mercury is a hazard, and I am glad that mercury thermometers are disappearing. But I would think that fluorescent light bulbs are a far more pervasive problem. They also contain a small amount of […]

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  6. Environment

    Old thermometers pose new problems

    Though health groups advocate getting mercury thermometers out of the home, obtaining sound advice on how to dispose of the thermometers can be problematic.

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  7. Earth

    Algae Turn Fish into a Lethal Lunch

    Scientists demonstrated that some marine mammals have died from eating fish tainted with a neurotoxic diatom.

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  8. Earth

    Most oil enters sea from nonaccidents

    Nearly all of the oil entering the marine environment traces not to accidents but to natural seeps and human activities where releases are intentional.

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  9. Astronomy

    Cosmic Dawn

    New computer simulations suggest that the first stars in the universe were extremely massive and left behind gamma-ray bursts that may already have been detected by telescopes orbiting Earth.

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  10. Health & Medicine

    What Activates AIDS?

    New studies suggest that a natural process called immune activation—the signaling that alerts immune cells of foreign invaders—plays a key role in explaining why infection with the human immunodeficiency virus progresses to AIDS more quickly in some people than in others.

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  11. Math

    A Stranger from Spaceland

    “It was the last day of the 1999th year of our era. The pattering of the rain To a Flatlander, a sphere passing through Flatland appears as a line of changing length. had long ago announced nightfall; and I was sitting in the company of my wife, musing on the events of the past and […]

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  12. From the December 28, 1929, issue

    YOUTH AND THE SEA “Captain Sylvia,” aged 6 weeks, and her mother, Mrs. J.E. Williamson upon the cover of this week’s issue look at a strange world full of fishes, corals, sharks, morays, and other denizens of the deep. The youthful scientist, symbolic of science itself and its aspirations, was a member of the Field […]

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