Faced with an ageing population and blessed with excellent engineers, Germany is increasingly looking to high technology to make geriatric medicine more effective and less obtrusive. In the western German city of Aachen, researchers have developed a dehydration sensor to remind elderly people - whose sense of thirst is reduced - when they need to drink something. Not getting enough fluids can have serious consequences for them, including cardiovascular problems, disorientation and a heightened risk of falling.