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This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute? There have been tremendous declines in fertility. The key has been the prevention of unwanted births, really around the globe. John Casterline directs the Initiative in
Scientific American(二)月
Approximately 6.6 billion people populate the earth today, with an estimated 3.7 billion living in Asia. But over the past 50 years, economic and social modernization in the region has been accompanied by a remarkable drop in birth rates. Sociologist
VOA标准英语2011年(一月)
Schools in north China's Shanxi Province have been banned from organizing overseas study tours for profit after a plane crash killed two Chinese girls in San Francisco. The provincial education department announced the ban in a statement issued on Tu
世界各地新闻集锦
专家预测:2050年地球将面目全非 The earth's population could top nine billion by 2050, leading to an 'unrecognisable' world as people compete for scarcer resources a U.S. science conference heard yesterday. 有美国科学家警告，到205
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Guys, heres another reason to eat your veggies: they might be good for your sperm. Some studies show that male fertility and whats called seminal quality have declined over the last few decades. So researchers from two fertility clinics in Spain loo
60秒科学
According to the Washington Post of September 26, Japan's government has been paying more attention to the nations fertility rate, which influences the country's economic development。 The coastal region of Fukui has Japan's biggest share of dual-in
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