In 1974, a young Xenia, Ohio, resident sweeps the slab of a house that was destroyed in a tornado that struck the town April 3. AP hide caption

Manning in 1945. She and dozens of other nurses were freed by U.S. forces earlier that year. U.S. Army Signal Corps hide caption

Mets phenom Dwight Gooden pitches at New York's Shea Stadium on May 6, 1984. Ray Stubblebine/AP hide caption

Rio's Operations Center brings together more than 30 agencies and allows them to coordinate on daily issues such as traffic, as well as on emergencies such as the frequent flash floods in hillside slums. Raphael Lima/Courtesy of the Operations Center, City of Rio De Janeiro hide caption

Information, like light, flows through cities in interesting, often beautiful, patterns. Valery Hache/AFP/Getty Images hide caption

Cover of What Soldiers Do hide caption

Washington Redskins owner Dan Snyder has vowed to never change the team's name. Manuel Balce Ceneta/AP hide caption

Jen Regan strokes the head of her fiancée, Marc Fucarile, as he sleeps in his hospital bed at Massachusetts General Hospital. Fucarile was injured in the bombings at the Boston Marathon, and had to have his right leg amputated. Bill Greene/Boston Globe via Getty Images hide caption