Injectable device designed to combat heart defects in newborns
                                
                                
                                    (Newser) -
                                    The average pacemaker is about the size of a walnut. But one created specifically for babies, announced by Northwestern University scientists, is far smaller—smaller, even, than a grain of rice,  CBS News  reports. Described as "the world's smallest pacemaker," the revolutionary device works in conjunction with...