Scientists at the National Center for Natural Products Research at the University of Mississippi have developed a system they say improves upon existing methods for testing mosquito repellents in a laboratory setting. Shown above, the system includes a 30- by 30- by 30-cm aluminum cage with a acrylic reservoir containing human blood, warmed to human body temperature by a water circulator below it. Over the blood, a sheet of collagen mimicks human skin. (Photo credit: Abbas Ali, Ph.D.)