Isotopic Bomb Traces Are a Boon to Biological Dating
The Scientist Magazine,
J onas Frisén wanted to answer a question: How often, if at all, do brain cells in the hippocampus turn over in adult humans?
J onas Frisén wanted to answer a question: How often, if at all, do brain cells in the hippocampus turn over in adult humans?
在世界上还有两个超级大国时,美国先搞出了原子弹。1949年,苏联也爆了颗 “斯大林1号”。美国一看这还了得?三年后就爆了颗氢弹。苏联又咬牙跟上。美国又再度加码……总之,从1951年到1962年的11年里,两个超级大国几乎年年换着花样地炸蘑菇云。直到苏联炸了枚…
在世界上还有两个超级大国时,美国先搞出了原子弹。1949年,苏联也爆了颗 “斯大林1号”。美国一看这还了得?三年后就爆了颗氢弹。苏联又咬牙跟上。美国又再度加码……总之,从1951年到1962年的11年里,两个超级大国几乎年年换着花样地炸蘑菇云。直到苏联炸了枚…
Greenland sharks are among nature’s least elegant inventions. Lumpish, with stunted pectoral fins that they use for ponderously…
Greenland sharks are among nature’s least elegant inventions. Lumpish, with stunted pectoral fins that they use for ponderously…
Age-related cataract and a reduction in the ability to focus (presbyopia) are very common vision problems in older people. New…