via digg.com: Stories / Popular on 6/1/09
Thomas Penzel studies sleep at the Charite Hospital in Berlin. He answers questions such as: how can you still be tired after eight hours sleep? Can you die from lack of sleep? Is afternoon napping a good idea? Should you wake a sleepwalker?
座头鲸数量恢复,形成大规模超群
1 天前
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