This method requires four or five months to develop a vaccine once a new strain is pinpointed.

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They calculate that within four years this method could even replace insecticide-treated bed nets as a way of controlling mosquitoes.

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There are, by this method of measuring things, four components in GDP.

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They also include the Rocket Stove built out of an old fuel can and the four-folded sari method in Bangladesh to remove cholera.

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More recently, the 2011 Wendy Schmidt Oil Cleanup X Challenge spurred an Illinois company to create a cleanup method for oil slicks that is four times more effective than any previous one.

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Researchers at 11 institutions are mapping the largest conduits among brain regions by combining four imaging techniques, including a new method called diffusion magnetic-resonance imaging that allows researchers for the first time to accurately map the white matter of nerve fibers.

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Alternative B would require two independent networks for each verification method, PIN and signature, for a total of four networks to each card.

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It follows four years of research and development aimed at finding a natural method of tackling the problem of sea lice.

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They know that retail merchants will not adopt a new payment method that only works with the subscribers of just one mobile operator and therefore excludes maybe three out of four customers in their store.

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