But the heat-driven Stirling engine design opens up possibilities for alternative fuels.

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The heat-driven storm that started Friday has resulted in at least 22 deaths from Ohio to New Jersey, 13 of them in Virginia.

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TC4 project will generate new data on the icy cirrus clouds that are formed in the upper atmosphere by heat-driven, or convective, storm systems that coalesce over warm waters in the tropics.

ECONOMIST: Climatology

That helps to explain the pushback from the State Department, which was publicly taking the heat -- and didn't want the CIA-driven talking points to add to the idea that they had failed to protect their own.

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But it appears to be a catalyst-driven chemical system that releases both heat and gas in sufficient quantities to pump the wings up and down.

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