Researchers at New York University Hospital worry the mice they use to study human disease may have perished in the flooding caused by Superstorm Sandy. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Hurricane Sandy's tear across the Caribbean left at least 54 dead in Haiti, where many people still live in tents because of damage from the 2010 earthquake. Thony Belizaire/AFP/Getty Images hide caption

itoggle caption Thony Belizaire/AFP/Getty Images

A lift to safety: New York City Police officers used "Helicopter 23" — named for the 23 officers killed on Sept. 11, 2001 — to rescue six people from rooftops on Staten Island. InsideNYPD hide caption

itoggle caption InsideNYPD

Rescue in Hoboken: Much of the New Jersey city remains flooded and the National Guard has been called in to help rescue stranded residents. Tuesday, this was the scene on one of the city's flooded streets. Eduardo Munoz /Reuters /Landov hide caption

itoggle caption Eduardo Munoz /Reuters /Landov

New Jersey Gov. Chris Christie gives a press conference on Hurricane Sandy in Old Bridge, N.J., on Monday. Marcus DiPaola/Xinhua /Landov hide caption

itoggle caption Marcus DiPaola/Xinhua /Landov

Ambulances line up outside New York University Langone Medical Center to evacuate patients after backup generators failed when Sandy knocked out power in Lower Manhattan Monday. John Minchillo/AP hide caption

itoggle caption John Minchillo/AP

In New York City's financial district, cars floated in a flooded subterranean basement a day after Hurricane Sandy tore across the East Coast. Andrew Burton/Getty Images hide caption

itoggle caption Andrew Burton/Getty Images

Fans like her style: Mayor Michael Bloomberg (at right) briefing New Yorkers about Hurricane Sandy on Monday. At left is his sign language interpreter, who the mayor identified as Lydia Callis. Mayor Bloomberg's YouTube channel hide caption

itoggle caption Mayor Bloomberg's YouTube channel

A screen grab from video of the Coast Guard's rescue operation that saved 14 sailors from the HMS Bounty on Monday. U.S. Coast Guard hide caption

itoggle caption U.S. Coast Guard