The University of Wisconsin and the Medical College of Wisconsin are two of the institutions taking part in a comprehensive study of concussions.  More than 40-thousand student-athletes in several sports are being studied.  Data has been collected on more than three-thousand concussions.  The School of Medicine and Indiana University is coordinating the data collected in the 46-million dollar project.  About two-thirds of Badger football players will be wearing helmets equipped with sensors to measure the impact of the hits they sustain.