By Brian Walker, CNN Yamada, Japan (CNN) -- Just over a month after the worst natural disaster in modern Japanese history, scientists and researchers are still trying to piece together the mystery of exactly how and why some ar… more »

By PAULINE ARRILLAGA, Associated Press TUCSON, Ariz. – Rep. Gabrielle Giffords remained heavily sedated and in critical condition Sunday as investigators sought to understand what motivated a gunman to carry out an assassination attempt on the Democra… more »