Vol. 158 No. #23 Archives

More Stories from the December 2, 2000 issue

  1. Earth

    Life Landed 2.6 Billion Years Ago

    Unusually carbon-rich rocks found in eastern South Africa may push back the evidence of life on land to 2.6 billion years ago, more than twice the current age of indisputably terrestrial organisms.

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  2. Animals

    First mammal joins the eusocial club

    Because naked mole rats exhibit permanent physical traits that distinguish certain castes of a colony, they belong to the same grouping as so-called eusocial insects such as bees, ants, wasps, and termites.

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  3. Math

    Prime proof zeros in on crucial numbers

    A new theorem may lead to a proof of Catalan's conjecture, a venerable problem in number theory concerning consecutive powers of whole numbers.

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  4. Planetary Science

    An early cosmic wallop for life on Earth?

    New evidence from lunar meteorites suggests that debris bombarded the moon some 3.9 billion years ago, about the same time that life may have formed on Earth.

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  5. Certain memories may rest on a good sleep

    People who practice a task that demands quick visual processing perform it better on ensuing trials if they are first allowed to get some sleep.

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  6. Health & Medicine

    Vaccine protects monkeys from Ebola virus

    A combination of a DNA vaccine and a vaccine based on a genetically modified common cold virus enables monkeys to resist Ebola virus, the first evidence that an Ebola vaccine works in primates.

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  7. Ecosystems

    Fly may be depleting U.S. giant silk moths

    A parasitic fly introduced to fight gypsy moths starting in 1906 may be an overlooked factor in the declines of giant silk moths.

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  8. Physics

    An electron ruler gauges crystal flaws

    Electrons ricocheting through a crystal now make it possible for scientists to discern shifts in crystal lattices as small as a hundredth of an atom's width.

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  9. Health & Medicine

    New sources and uses for stem cells

    Human skin and scalp tissue may provide a source of neural stem cells.

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  10. Health & Medicine

    Pesticide tied to Parkinson’s disease

    Rodents exposed to massive amounts of the pesticide rotenone develop a condition similar to Parkinson's disease.

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  11. Health & Medicine

    Old antibiotic takes on Alzheimer’s

    An antibiotic that binds copper and zinc may prevent brain deposits that cause Alzheimer's disease.

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  12. Health & Medicine

    Does vitamin A aid learning?

    A lack of Vitamin A may cause learning and memory problems, albeit potentially reversible ones.

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  13. Health & Medicine

    New role for cholesterol-lowering drugs

    Drugs that lower cholesterol benefit patients who have just had a heart attack or chest pains, regardless of the patient's initial cholesterol levels.

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  14. Health & Medicine

    It’s that time. . .for heart attacks?

    A small study of young women already at high risk of having a heart attack suggests that heart attacks are most frequent when estrogen levels are low, soon after a woman's period begins.

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  15. Health & Medicine

    Big meals boost heart attack risk

    Unusually heavy meals boost a person's chance of developing a heart attack, at least among those people who already have risk factors for heart disease.

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  16. Health & Medicine

    Teasing out tea’s heart-healthy effect

    Drinking black tea makes a person's blood vessels dilate more easily, which may explain why drinking tea can protect against heart disease.

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  17. Health & Medicine

    Nitric oxide may benefit damaged hearts

    A small study in mice suggests that inhaling nitric oxide may protect against tissue damage after a heart attack.

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  18. Animals

    Will Mr. Bowerbird Fall for a Robot?

    Push a button and she turns her head. But can she turn his?

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  19. Materials Science

    One-Upping Nature’s Materials

    Striving for designer substances that build themselves from individual molecules.

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