7/11/2012 - Col. Lee Harvis, 374th Medical Group outgoing commander, renders his final salute to his unit during a change of command ceremony at Yokota Air Base, Japan, July 9, 2012. The tradition of the military salute can be traced back to medieval knights raising their visors when passing their superiors. This age-old gesture is a universal symbol of mutual respect. (U.S. Air Force photo by Airman 1st Class John D. Partlow)

7/11/2012 - Col. Lee Harvis, 374th Medical Group outgoing commander, center, hands the group guidon to Col. Mark August, 374th Airlift Wing commander, left, during a change of command ceremony at Yokota Air Base, Japan, July 9, 2012. The guidon is a tradition dating back to Roman times, where military units would carry a banner with their emblem into battle. (U.S. Air Force photo by Airman 1st Class John D. Partlow)

7/11/2012 - Col. Mark August, 374th Airlift Wing commander, left, hands the 374th Medical Group guidon to Col. Eveline Yao, the new 374 MDG commander, during a change of command ceremony at Yokota Air Base, Japan, July 9, 2012. The passing of the guidon to the new commander signifies the start of the new command. (U.S. Air Force photo by Airman 1st Class John D. Partlow)

7/11/2012 - Col. Eveline Yao, the new 374th Medical Group commander, renders her first salute to her unit during a change of command ceremony at Yokota Air Base, Japan, July 9, 2012. (U.S. Air Force photo by Airman 1st Class John D. Partlow)

7/11/2012 - Col. Eveline Yao, the new 374th Medical Group commander, meets with local Japanese dignitaries after a change of command ceremony at Yokota Air Base, Japan, July 9, 2012. (U.S. Air Force photo by Airman 1st Class John D. Partlow)