i'm very fortunate to have the opportunity to work with glenn fishman. taken this out of the mouse and hooked it up through the aorta to profuse it, to keep it happy. we can look at that both in normal conditions as well as in some of the genetically engineered mice that we've made without gap junctions or with other channel abnormalities and try to understand why they get arrhythmias, which is really the main question that's driving us here. if we understand the biology of the pacemaker cells, it's our hope that we can regenerate portions of the conduction system by re-implanting cells that take on this function from those that have degenerated in the patient. more broadly, in terms of the whole heart's electrical system, if we can understand the basis for many forms of lethal cardiac arrhythmias, we can go in and treat those sorts of diseases. cardiovascular disease is the leading cause of mortality in the united states, and sudden cardiac death from arrhythmias is the leading cause of death within the cardiovascular category. it's clearly relevant jus