We’ve all had cuts and scrapes and most of them have healed pretty quickly. Well, the chronic wounds (i.e. diabetic ulcers) that affect 6 million US patients per year require a little more attention than antiseptic and a band aid. So much in fact that the US health care system spends an estimated $20B annually on treating these wounds. Cue the brilliant minds at Drexel University who have created a small, battery-powered, wearable device that uses low-frequency ultrasound to heal wounds. This caught the attention of the NIH who has awarded Drexel $3M to test the therapy over the next five years. Batteries make terrible band aids, but 6M patients a year means they’ll be in a lot of medicine cabinets.