Translating medical research into practice is never easy, but Dr. Ben Abella, a co-author on the Circulation paper and the clinical research director of the Center for Resuscitation Science, says that hypothermia is an especially hard pill for some to swallow.

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The research is published in Circulation, an American Heart Association journal.

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Some 25 million pieces were in circulation in 1863 and '64, according to research by Robert Leonard Jr. of the Chicago Coin Club.

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The findings, published independently by two research teams using similar data, are in the medical journals Circulation: Journal of the American Heart Association and Journal of the American College of Cardiology.

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