Neil Johnson, a University of Miami physicist, developed this mathematical formula to predict insurgent attacks in war zones. Courtesy of Neil Johnson hide caption

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Tents burn on March 16 as Bahraini security troops raid the site of a pro-democracy sit-in at Pearl Square, in the capital, Manama. Joseph Eid/AFP/Getty Images hide caption

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Former President Hosni Mubarak, seen Feb. 8 at the presidential palace in Cairo, faces charges of corruption and ordering the killing of protesters during the uprising against him. Amr Nabil/AP hide caption

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A Libyan rebel fighter flashes a victory sign as an aircraft carrying supplies for the rebels departs along a guarded mile-long stretch of road being used as runway, outside of Rhybat in western Libya, on July 19. Gaia Anderson/AP hide caption

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Protesters in Cairo's Tahrir Square shout slogans against Egypt's military rulers on Sunday. Six months after political upheaval led President Hosni Mubarak to step down, activists say reform has stalled. Amr Nabil/AP hide caption

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Libyan rebel fighters run for cover at the front line near the southwest desert town of Gualish on July 24, as Gadhafi forces started attacking them in an attempt to capture the city. Colin Summers/AFP/Getty Images hide caption

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Relatives and friends mourn over the coffin of Darioush Rezai-Nejad in Tehran, Iran. Rezai-Nejad was killed in a deadly shooting on Saturday. Iran said he was a university student — not a nuclear physicist. AP hide caption

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