Microsoft founder Bill Gates, his wife Melinda French Gates and British Prime Minister David Cameron at the World Economic Forum on January 28, 2011, in Davos, Switzerland. Johannes Eisele/AFP/Getty Images hide caption

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At the Cleveland Clinic, technician Larry Raber and physician Mei Lu practice the ultrasound technique to measure CCSVI in patients with MS on medical student Claudiu Diaconu. Cleveland Clinic Center for Medical Art & Photography hide caption

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Author Toni Bernhard, who is house-bound and often bed-bound, says she's learned to cultivate joy through others. Courtesy of Wisdom Publications hide caption

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President Barack Obama said he was open to improvements to the health overhaul law during his State of the Union speech earlier this week. Brendan Smialowski/Getty Images hide caption

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Bacon is cut from the pig's belly, and is one- to two-thirds fat. Justin Sullivan/Getty Images hide caption

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A traveler passes an automated external defibrillator at O'Hare International Airport in Chicago. Tim Boyle/Getty Images hide caption

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Las Vegas police stand guard outside Harrah's hotel-casino in Las Vegas on Feb. 21, 2006. As officer Norman Jahn recalls, police arrested the suspected gunman without firing a shot. Jae C. Hong/AP hide caption

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