In this Jan. 18 photo provided by the NYU Langone Medical Center, a technician examines mice to determine their health at the hospital's complex in New York. New York University/AP hide caption

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In Clarksville, Mo., Bob Bailey adjusts a pump as he tries to keep floodwater from the Mississippi River out of a rental property Sunday. The small community has worked for days to build a makeshift sandbag levee. Jeff Roberson/AP hide caption

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An Emergency Ministry soldier helps to repair religious icons in a church hit by flood water in the town of Nizhnebakansky, about 750 miles south of Moscow, on Tuesday. Sergey Ponomarev/AP hide caption

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A levee protects a home surrounded by floodwater from the Yazoo River near Vicksburg, Miss., May 18, 2011. Scott Olson/Getty Images hide caption

itoggle caption Scott Olson/Getty Images