The U.S. hopes to repeat as Paralympic gold medalists in sled hockey Saturday, when the team will play host Russia. Earlier this week, Nikko Landeros of USA was chased by Dmitrii Lisov of Russia during group play at the Sochi 2014 Paralympic Winter Games. Harry Engels/Getty Images hide caption

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Archer Matt Stutzman of the U.S. prepares to shoot in the London Paralympics. Born without arms, Stutzman uses a release trigger strapped to his shoulder to fire. Dennis Grombkowski/Getty Images hide caption

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Bronze medalist Arnu Fourie of South Africa (from left), gold medalist Jonnie Peacock of Great Britain, silver medalist Richard Browne of the United States and Oscar Pistorius of South Africa cross the line in the Men's 100m - T44 Final at London's Olympic Stadium. Jamie McDonald/Getty Images hide caption

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In a surprise finish, Brazil's Alan Fonteles Cardoso Oliveira (left) races past South Africa's Oscar Pistorius to win a gold medal in the 200-meter race at the 2012 London Paralympic Games. Emilio Morenatti/AP hide caption

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Alex Zanardi celebrates winning the gold medal in the men's individual H4 time trial cycling final at the London 2012 Paralympic Games at Brands Hatch circuit, in Kent, southern England. Zanardi's legs were amputated after a racecar crash in 2001. Leon Neal/AFP/Getty Images hide caption

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Oscar Pistorius of South Africa runs in the men's 200-meter event at the Paralympic World Cup in May. Some observers have suggested Pistorius receives an unfair advantage from his carbon-fiber "blade" legs. Michael Steele/Getty Images hide caption

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