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This is Scientific Americans 60-Second Science. Im Cynthia Graber. This will just take a minute. Saliva contains many useful components: lubricants, enzymes for breaking down food and now compounds that can reveal a persons age. Thats according to a
Scientific American(六)月
Ever get a sour stomach after your morning coffee? Well, you might end up switching to a dark roastbecause that coffee concoction may leave you with a happier tummy. That's according to the research presented at the American Chemical Society meeting
Scientific American(三)月
We present the second of three parts of the short story Benito Cereno. It was written by Herman Melville. Last week, we told how African slaves on a Spanish ship rebelled in seventeen ninety-nine. They killed most of the Spanish sailors. Only the cap
2017年VOA慢速英语(十二)月
We present the last of three parts of the short story Benito Cereno. It was written by Herman Melville. As we told you in earlier parts of our story, rebel slaves seized the ship San Dominick off the coast of Chile. They killed many of its officers a
2017年VOA慢速英语(十二)月
AGRICULTURE REPORT - Restrictions on Methyl Bromide By Mario Ritter Broadcast: Tuesday, March 16, 2004 This is Steve Ember with the VOA Special English Agriculture Report. Graphic Image Some chemicals
农业与发展
Science and Technology Epigenetics and stress Baby blues 科技 外因遗传与压力 新生儿蓝调曲 A mother's stress while she is pregnant can have a long-lasting effect on her children's genes 母亲孕期压力过大会对孩子的基因造成长
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