Vol. 159 No. #8
Archive Issues Modal Example

More Stories from the February 24, 2001 issue

  1. Paleontology

    Extinctions Tied to Impact from Space

    Evidence trapped in 250-million-year-old sediments may help researchers pin the ultimate blame for the massive extinctions that occurred then on the impact of an extraterrestrial object about 9 kilometers across.

  2. Health & Medicine

    Sometimes an antibiotic is much more

    By reining in destructive enzymes in the body, tetracyclines can thwart various diseases, including periodontal bone loss and cancer.

  3. Health & Medicine

    Color array reveals breast cancer types

    A suite of genes lights up when researchers probe for cancer.

  4. Physics

    Seeming sedate, some solid surfaces seethe

    Although they're as orderly as bathroom-floor tiles, surface atoms of copper--and perhaps other solids--actually roam randomly and widely within their grid.

  5. Can visiting a plant ruin an experiment?

    Merely walking up to a plant and handling its leaves may skew outcomes in studies of predators attacking plants.

  6. Astronomy

    Distant cluster suggests low-weight cosmos

    Lured by the radio beacon of a faraway galaxy, astronomers have discovered the most distant cluster of galaxies known in the universe.

  7. Astronomy

    Ancient Mars water: A deep source?

    A new analysis of a Mars meteorite that fell to Earth suggests that much of the water believed to have once flowed on the surface of the Red Planet came from eruptions of molten rock that originated deep within the planet.

  8. Astronomy

    Cassini at Jupiter: Eyeing the Io torus

    The Cassini spacecraft has captured the most detailed images ever taken of the Io torus, a doughnut-shaped ring of charged particles that surrounds Jupiter and is replenished by the planet's moon Io.

  9. Physics

    Muffled shots tell a lot about snow

    A snowfield muffles gunshots in a way that can now be used to reveal important traits of the snow.

  10. Physics

    Lasers nudge into nuclear medicine

    Using a tabletop laser, researchers produced a medically useful isotope usually made in warehouse-size particle accelerators called cyclotrons.

  11. Health & Medicine

    Anti-HIV mutation poses hepatitis risk

    A genetic mutation that protects people from AIDS may also make them susceptible to hepatitis C.

  12. Health & Medicine

    Some HIV patients getting transplants

    Organ transplants succeed in some HIV-infected people, spurring further research into this practice.

  13. Health & Medicine

    AIDS drug performs well in early test

    A new drug called T-1249, which keeps the AIDS virus from fusing with immune cells, proves largely safe in people.

  14. Health & Medicine

    AIDS-treatment guidelines revised

    A panel of scientists has changed the guidelines for prescribing medication for HIV-infected patients, considerably lowering the suggested T-cell-count and HIV-copy thresholds.

  15. Earth

    A Nation Aflame

    In the wake of one of the worst fire seasons in the past 50 years, scientists are assessing risk as more people move into fire-prone areas and developing ways to better predict the behavior of--and the potential for--wildfires.

  16. Astronomy

    Mining the Sky

    A proposed national virtual observatory, a mammoth computer database integrating spectra, images, and other information covering the entire sky, could usher in a new age of discovery in astronomy.