Inside a Brown's Super Store. Brown's operates seven profitable supermarkets in low-income neighborhoods in Philadelphia. Courtesy of Brown's Super Stores, Inc. hide caption

itoggle caption Courtesy of Brown's Super Stores, Inc.

Emergency personnel search through the wreckage of an Amtrak train that derailed Tuesday night in Philadelphia, killing at least five people who were on board. Joseph Kaczmarek/AP hide caption

itoggle caption Joseph Kaczmarek/AP

Measles is highly contagious, and it produces fever and rash in susceptible people who become infected. Hazel Appleton/Health Protection Agency Centre/Science Source hide caption

itoggle caption Hazel Appleton/Health Protection Agency Centre/Science Source

New apartment buildings are replacing empty lots in Mantua, one of Philadelphia's poorest neighborhoods. Will Figg for NPR hide caption

itoggle caption Will Figg for NPR

Philadelphia City Councilwoman Maria Quinones-Sanchez pushed for the city to change its practice of detaining immigrants on behalf of federal officials. Matt Rourke/AP hide caption

itoggle caption Matt Rourke/AP