Human sexuality researchers William Masters and Virginia Johnson Masters, shown in San Francisco in 1972. AP hide caption

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Former Democratic Rep. Lindy Claiborne Boggs attends the Distinguished Service Award ceremony at the Capitol in May 2006 in Washington, D.C. Chip Somodevilla/Getty Images hide caption

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When Gene Krupa's orchestra was cast in 1941's Ball of Fire, trumpeter Roy Eldridge's presence was not negotiable. Express/Getty Images hide caption

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In his latest book, Savage Continent, Keith Lowe takes a look at Europe in the years directly following World War II. Picador hide caption

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Seasonal Ranger Mike Donahue (right) discuses the Battle of Little Bighorn with Jon Jones atop Custer Hill. Jim Kent/NPR hide caption

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Judy Brewer was the country's first full-time female firefighter. John Duricka/AP hide caption

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Children with tuberculosis sleep outside at Springfield House Open Air School in London in 1932. Like sanatoriums, these schools offered TB sufferers a place to receive the top treatment of the day: fresh air and sunshine. Fox Photos/Getty Images hide caption

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Sylvester's 1978 album Step II resulted in a couple of smash singles, "Dance (Disco Heat)" and "You Make Me Feel (Mighty Real)." Fantasy Archives hide caption

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Take a tour of the Hanford site, a nuclear production complex in Richland, Wash., and you'll see the hundreds of mechanical water pressure gauges wired to the process tubes inside the core. Tour guide Paul Vinther warns that bumping these gauges could throw off the readings enough to trigger a an emergency shutdown of the reactor. Martin Kaste/NPR hide caption

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