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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

发表于:2018-12-24 / 阅读(63) / 评论(0) 分类 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

发表于:2018-12-24 / 阅读(66) / 评论(0) 分类 Scientific American(三)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

发表于:2019-01-06 / 阅读(84) / 评论(0) 分类 农业与发展

By George Dwyer Washington, DC 06 March 2006 watch Mining Workers Mexican mine worker Thousands of miners in Mexico have begun returning to work after walking off the job last week to protest working

发表于:2019-01-09 / 阅读(95) / 评论(0) 分类 2006年VOA标准英语(三月)

An ass and an ox,fastened to the same yoke,were draging a waggon.While the ox was pulling with all his might he he broke a horn.The ass swore that he had got no help whatever from his weak companion.Exerting himself in the labour,the ox b

发表于:2019-01-09 / 阅读(111) / 评论(0) 分类 趣味英语

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

发表于:2019-01-26 / 阅读(58) / 评论(0) 分类 经济学人科技系列