Abstract: A wireless power transfer secondary or pick-up has a resonant circuit and a switch connected to the resonant circuit operable to produce a phase shift in an oscillating voltage or current in the resonant circuit. A controller is configured to operate the switch to introduce one or more controlled phase shifts in the oscillating voltage or current in the resonant circuit which encode data for detection by a coupled circuit.

Abstract: A system for separating motile and non-motile sperm comprises a microvolume into which a fluid containing sperm is delivered, at least partly defined by a wall which includes a termination or a change in angle away from the microvolume, defining an exit from the microvolume. Sperm delivered into the microvolume in a fluid that are motile move entrained along the wall and leave the wall at the termination with an outward turn to or towards a collection reservoir or passage from the microvolume. Typically the system is implemented on a microfluidic chip.