england's biomechanical engineering department at leeds university is a global leader in replacement body parts, specialising in living heart valves, knees and spinal disc replacement, but their biggest success story has been in developing a new super artificial hip. >>fisher: well our laboratory simulation predict that this particular bearing combination of ceramic on metal will last up to 50 years and that's effectively in active patients up to 100,000,000 steps and that's 2 to 3 times longer than hip joints that have previously been available. >>milns: historically medical research has focused more on improving the longevity of life, but this project really steps it up a gear. it's about staying active no matter what your age so that you can always keep up with the guy next door, come on frank >>reporter: good news for pensioners who are willing to keep themselves active. 84-year-old mary thornton had a knee replacement last year but is still as sprightly as ever. >>old age creeps up and that is the time that people don't realise that they still have to be activeif they wish to ca

meredith was her flatmate, a bright 21-year-old student studying language at leeds university.g a one-year placement in the italian town of perugia, she was stabbed and sexually assaulted in 2007, a crime of which amanda and her boyfriend were convicted, a drifter from the ivory coast, he was also convicted of her murder in a separate trial. this is the house where meredith grew up, a quiet town south of london. the kercher family have always maintained that they thought that the trial was fair. meredith's father john wrote in one newspaper that amanda knox has been convicted of taking our precious meredith's life in the most hideous and bloody way. the prospects of amanda being released will be very upsetting to the kercher family. the neighbor, maureen, says the appeal has put meredith's family under enormous strain. >> because it's been going on for four years. i mean, there was the initial murder, and then, of course, there was the trial and since then it always seems to be in the news. and as i say, meredith seems to be forgotten in it. she was beautiful, she was friendly,