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In this photo provided by Diana Nyad via the Florida Keys News Bureau, endurance swimmer Diana Nyad swims in the Florida Straits between Cuba and the Florida Keys Sunday, Aug. 19, 2012, escorted by support personnel in kayaks. Nyad is endeavoring to become the first swimmer to transit the Florida Straits from Cuba to the Keys without a shark cage. The white underwater strip, tethered to the boom from her primary support vessel, provides Nyad a moving swimming lane so she can maintain a proper course.
(AP Photo/Diana Nyad via the Florida Keys News Bureau, Christi Barli)