U.S. Air Force Lt. Col. David Hall, left, provides dental care to a patient during a New Horizons medical readiness and training exercise in San Miguel, Peru, July 24, 2012. New Horizons is a U.S. Southern Command-sponsored annual series of joint humanitarian assistance exercises deploying U.S. military engineers, veterinarians, medics and other professions to Central and South American nations for training, construction projects and to provide humanitarian and medical services. (U.S. Air Force photo by Staff Sgt. Michael C. Zimmerman/Released)