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  1. Earth

    Amazon basin is wetter now than in past

    Sediments from the Atlantic Ocean indicate that the now lush Amazon Basin was much drier during the latest ice age.

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  2. Earth

    Explorers pinpoint source of the Amazon

    A five-nation team of explorers has used Global Positioning System equipment to confirm that the source of the Amazon is a snowmelt-fed stream high in the Peruvian Andes.

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  3. 18898

    Both definitions of “source of the Amazon” advanced by its would-be finders are capricious. They imply that a river can be a lesser stream than its tributary, which runs counter to any plausible definition of tributary. Travel up the Amazon and at every fork take the branch with greater water flow. You will eventually reach […]

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  4. Chemistry

    For a better smile, have some wasabi

    Chemicals in the Japanese condiment wasabi could help prevent tooth decay.

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  5. Chemistry

    Where the tire meets the conveyor belt

    A new, noninvasive technique could detect an impending failure in a rubber tire or conveyor belt.

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  6. Health & Medicine

    Cocaine link to heart attack bolstered

    Regular cocaine use may account for one-fourth of nonfatal heart attacks in people under age 45.

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  7. Health & Medicine

    Gene mutation can spur autoimmunity

    A mutation of a gene on the X chromosome can lead to a dangerous autoimmune disorder and type I diabetes.

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  8. Astronomy

    A Jovian moon lost and found

    After 25 years, astronomers have relocated a tiny satellite of Jupiter.

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  9. Astronomy

    A trio of new planets

    With the discovery of three additional planets that lie outside the solar system, astronomers have now found evidence of more than 50 extrasolar planets.

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  10. Health & Medicine

    Mending a Broken Heart

    Transplants of skeletal-muscle cells may help heal hearts damaged by illness or previous heart attacks.

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  11. 18896

    The story “Stormy weather” carries some statements that I think need clarification: “If high-energy protons happen to strike astronauts outside the shelter of their spacecraft, they could be severely injured” or even killed. “Because the ionosphere absorbs much of the protons’ energy, they don’t pose a threat to people or electrical systems on Earth.” However, […]

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  12. Planetary Science

    Stormy Weather

    The 11-year cycle of solar storms has begun to peak, already affecting several Earth satellites and disturbing electric power systems on the ground, and scientists expect 2 more years of this solar maximum turmoil.

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