The new, oldest woman in the world, Misao Ohkawa celebrated her 115th birthday in the western Japanese city of Osaka yesterday. Ohkawa was officially recognized by the Guinness World Records as the oldest woman alive last week when she was only 114. Ohkawa was asked what the secret to longevity was. She said simply "Sleep well, and eat well." That must be emphasized in that country because Japan has more than 50,000 centenarians, and the world's oldest man is also Japanese - Jiroemon Kimura, who turns 116 in a month's time.