When you think about it, scientists and cowboys have a lot in common. Both are frontiersmen of a sort, both wear clothes that make them easy to identify and now they both count lassos among their essential tools. Researchers at the University of Bristol and the University of Dundee have wrangled small particles and cells by using a sonic (or ultrasonic) vortex. The whirl of sound waves allowed the teams to catch, move and orient microscopic particles, all without actually contacting them physically, which makes the solution ideal for handling delicate material. Professor Bruce Drinkwater from Bristol even suggested it could one day be used to assemble human tissue (custom assembled livers,