Velcro is a brand name of fabric hook-and-loop fasteners. It was invented by a Swiss engineer who came up with the idea after examining the burdock seeds that kept sticking to his clothes. Velcro consists of a layer of hooks and a layer of loops which, when pressed together, form a bond that can be very strong: full-body hook and loop suits have been made that can hold a person to a suitably-covered wall. Velcro was even involved in the first medical procedure of what kind? Discuss