U.S. Marine Corps Gen. James Amos testifies on Capitol Hill in September. Amos, now the Marine Corps' top officer, told Congress earlier this month that "don't ask, don't tell" should remain the law of the land. Alex Brandon/AP hide caption

Megan Lindsey (right) and her friend Alexandria Bodfish at soccer camp at University of Notre Dame.  Megan, 14, suffered concussions twice this fall while playing soccer. Courtesy of Barbara Wirtz hide caption

Cycling has at least tripled over the past two decades in several big cities across the U.S., including Minneapolis, Chicago and San Francisco. Jonathan Steinberg hide caption

Throughout Haiti, there were repeated scenes of voters who couldn't find their names on election sheets. Jason Beaubien/NPR hide caption

President Johnson (center) signs the Medicare Act in 1965 as former President Harry Truman (right) looks on. Now the cost of Medicare threatens to crush the federal budget. LBJ Library/National Archives hide caption

The deep-water-research submarine Alvin is launched from Atlantis. Scientists are studying how ecosystems in the Gulf of Mexico may have been affected by the Deepwater Horizon oil spill. Richard Harris/NPR hide caption