Tech. Sgt. Benjamin McReynolds, 28th Medical Support Squadron laboratory operations NCO in charge, analyzes a slide of blood after staining it in the clinical laboratory on Ellsworth Air Force Base, S.D., July 27, 2012. The stain makes it easier to tell the difference between blood cells, problem cells and parasites, producing faster and more accurate results. (U.S. Air Force photo by Airman 1st Class Kate Thornton/Released)