U.S. Air Force Senior Airman Destini Oglesby, 633rd Medical Operations Squadron Pulmonary Clinic lab technician, tests a ventilator at Langley Air Force Base, Va., March 6, 2012. Pulmonary specialists at USAF Hospital Langley use ventilators to assist patients who have difficulty breathing on their own while under intensive care. (U.S. Air Force photo by Airman 1st Class Teresa Cleveland/Released)