A patient at Langley Air Force Base, Va., lies still so a 633rd Medical Group medical technician can apply diodes to his body prior to an echocardiogram March 26, 2013. In addition to viewing a Doppler-enhanced ultrasound, the echocardiogram also allows medical personnel to listen to the heart beat. (U.S. Air Force photo by Airman 1st Class Austin Harvill/Released)