Unlike existing techniques which rely on expert visual assessment or unreliable biochemical measurements, this new "optical stretcher" tests the physical strength of each cell and can give a diagnosis using as few as 50 cells, allowing doctors to test for cancer where traditional biopsies are dangerous or even impossible.

A leading bio-physicist will announce a major breakthrough in stem cell research a new tool that could allow scientists to harvest stem cells ethically and not from embryos.

Nobel laureate Steven Chu will make a plea for scientists to look at nature's blueprint to help develop carbon-neutral energy sources. Oil and gas production is likely to peak within a generation and heavily polluting coal could be strung out for a few centuries. But Chu will say that biological enzymes could be the key to efficient new ways of producing energy.

Scientists have developed a new breed of sensors which can survive incredible levels of pressure and heat and that are helping researchers work out how to make buildings that could survive massive explosions.

'"/>