MICROSCOPIC submarines powered by bacteria could zip round the body delivering drugs and zapping tumours, say researchers in Utah who are developing a novel biomotor.

Tiny balls of silica can transform the humble honey bee into a highly effective mine detector, say researchers from the Sandia National Laboratories in Albuquerque, New Mexico. The Sandia researchers announced last year that they had been testing bees\' ability to detect mines. There are about 120 million land mines strewn around the world.