1. From the Glasgow Experimental MRI Centre (GEMRIC) (C.M., L.G., I.M.M.), Division of Clinical Neuroscience, Garscube Estate, University of Glasgow, Glasgow, Scotland; Biological Imaging Centre (W.G.), MRC Clinical Sciences Centre, Imperial College London, London, England; and Division of Cardiovascular and Medical Sciences (D.G., A.F.D.), BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, Scotland.