Peter Piot was one of the co-discoverers of the Ebola virus in 1976. "I never thought we would see such a devastating and vast epidemic," he says. Leon Neal/AFP/Getty Images hide caption

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A woman walks with children at an orphanage in Addis Ababa, Ethiopia. Policymakers have long called for orphans to be taken out of institutions and placed with foster families, but one study from Duke University is challenging that notion. Sean Gallup/Getty Images hide caption

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An Israeli soldier launches a drone that's attached to a military vehicle in southern Israel, not far from the border with the Gaza Strip, on July 29. Israel was a pioneer with drones and has developed a number of military technologies that it later sells abroad. Jim Hollander/EPA/Landov hide caption

itoggle caption Jim Hollander/EPA/Landov

A Malaysia Airlines crew member inspects an airplane at Kuala Lumpur International Airport on Thursday. The carrier announced it was laying off a third of its workforce amid steep financial losses. Azhar Rahim/EPA/Landov hide caption

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The orchids that produce vanilla beans have no natural pollinators in Madagascar; the plant must be pollinated by hand — a labor-intensive process with little margin for error. Courtesy of Madécasse hide caption

itoggle caption Courtesy of Madécasse

Britain's Prime Minister David Cameron speaks at a news conference in London on Friday after the U.K. raised its terror alert level. Paul Hackett/PA Photos/Landov hide caption

itoggle caption Paul Hackett/PA Photos/Landov

An Iraqi child walks next an empty house of a Christian family in Mosul on Aug. 8. The Arabic writing on the wall reads "Real Estate of the Islamic State." The extremist group took control of Mosul, Iraq's second largest city, in June. STR/EPA/Landov hide caption

itoggle caption STR/EPA/Landov

This image, posted on a militant website, shows an Islamic State fighter waving a flag from a captured government fighter jet in Raqqa, Syria. The group is well-funded and has gained territory over the past few months; that's raised some concerns in America, although experts say the organization is largely focused on regional goals. AP hide caption

itoggle caption AP