Helping employees take the time to go for a walk instead of reaching for junk food when energy flags boosts productivity, some firms find. Jamie Grill Photography/Tetra Images/Corbis hide caption

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Vice President Biden (from left), Health and Human Services Secretary Kathleen Sebelius, President Obama and Budget Director Sylvia Mathews Burwell at the White House Friday. Sebelius is stepping down. Burwell is being nominated to replace her. Charles Dharapak/AP hide caption

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Data released Wednesday about Medicare payments to doctors in 2012 have raised questions, but some experts warn against drawing "sweeping conclusions" from the numbers. iStockphoto hide caption

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Janelle Arevalo, an insurance agent with Sunshine Life and Health Advisors, makes a house call in Miami to sign up Sandra Berrios (left) for an insurance plan under the Affordable Care Act. Joe Raedle/Getty Images hide caption

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Laura Breland gets her teeth cleaned by Denise Lopez-Rodriguez at a community health center in Aurora, Colo., in 2012. Dental coverage is available through the Affordable Care Act. John Moore/Getty Images hide caption

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