achalasia animal testing artificial heart artificial kidney artificial lung artificial pacemaker artificial pancreas biological neural network bionics brain brain pacemaker cardia cardiac pacemaker cochlear implant computer science corpus cavernosum penis deep brain stimulation dialysis digital camera electronics epilepsy esophageal cancer gastroesophageal reflux disease hip replacement human image information processing kevin warwick kidney life support liver long-term memory machine translation memory mnemonic newcastle university open source hardware optic nerve organ transplant prosthesis research retina short-term memory stomach surgical oncology translation tremor visual perception