Feature

  1. Health & Medicine

    A Different Side of Estrogen

    Understanding estrogen's function is complicated by the fact that it can bind to two distinct receptors; scientists studying the second receptor now think that drugs targeting it could help a wide variety of ailments.

    By Sarah Williams
  2. Humans

    Science News of the Year 2007

    A review of important scientific achievements reported in Science News during the past year.

    By Science News
  3. Math

    Tied Up in Knots

    Physicists have shown that tumbled strings will form surprisingly complex knots, helping explain how knots spontaneously form in nature.

    By Davide Castelvecchi
  4. Earth

    Dead Serious

    Little progress has been made this decade in reducing the size of the Gulf of Mexico's dead zone, a massive area of oxygen-depleted water caused by agricultural and urban runoff.