The fluctuation is about 50 parts in a billion, less than a single grain in a bag of sugar.

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To better understand this, visualize a single grain of sand.

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Believe it or not, the cleaning must be sufficiently scrupulous so as to ensure that not a single grain of desert sand is transported out of the Middle East, lest it carry bacteria or diseases back to U.S. shores.

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When the Young Entrepreneur Council asked AJ Kumar, co-founder of digital marketing agency Single Grain, for tips to help business owners (ethically) boost their Web traffic, the majority of ideas on his extensive list of 20 suggestions revolved around providing visitors with more and better content.

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The separate elements are so perfectly joined together that the Riva looks as if it might have been carved out of a single tree, the grain of the cedar lustrous under gleaming varnish.

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Since 1 calorie of beef requires 8 times as much input of grain as a single calorie of bread, Petrela recognizes that rising protein consumption means a rising demand for grains which in turn means a rising demand for global farmland.

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It is the only pure Irish pot still whiskey available in the U.S. Unlike the vast majority of Irish whiskies, it is entirely made from malted and malted barley, while almost all other have the addition of grain-whiskey, one of the same key differentiators between single malt and blended whiskies.

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