President Barack Obama walks with Brazilian President Dilma Rousseff, second from right, during a visit to the Martin Luther King Jr. Memorial in Washington, D.C., on Monday. Evan Vucci/AP hide caption

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Federal agents seized Elián González, held in a closet by Donato Dalrymple, in Miami in April 2000. Dalrymple rescued the boy from the ocean after his mother drowned when they tried to escape Cuba. Alan Diaz/AP hide caption

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Colombian cyclist Nairo Quintana poses for a snapshot during a training session this month in Colombia. LUIS ACOSTA/AFP/Getty Images hide caption

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Soda delivery in Bosque de Chapultepec, Mexico City. Between 1989 and 2006, the consumption of sugary drinks increased by 60 percent per capita in Mexico. Omar Bárcena/Flickr hide caption

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The Brazilian national flag flutters at the front of the headquarters of the Brazilian state oil giant Petrobras, in Rio de Janeiro. Vanderlei Almeida/AFP/Getty Images hide caption

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Fernando Urias (left) and Victor Manuel Aguirre kiss after they learned they were allowed to marry, during a protest outside the municipal palace in the northern border city of Mexicali, Mexico, on Jan. 17. Alex Cossio/AP hide caption

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Pots with genetically modified male Aedes aegypti mosquitoes are pictured before they are released in Piracicaba, Brazil in April. Paulo Whitaker /Reuters /Landov hide caption

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