Any Human Heart writing again of a whole-life view: "I don't think there's anything wrong with going back over territory you've previously covered." Though avowedly not an (auto-)biographical novelist, Boyd acknowledged that personal experiences often subconsciously affect a writer's fiction. As in several of Boyd's novels there are parallels with the author's life: both Boyd and Mountstuart lived in Africa and France, studied at Oxford, worked in literary London and had a taste of New York. Boyd usually splits the creation of a novel into two phases: research and writing. The first phase of "Any Human Heart" took 30 months as he carefully
Heart within the ventricles falls below the pressure within the aorta and pulmonary arteries, the aortic and pulmonary valves close. The ventricles start to relax, the mitral and tricuspid valves open, and the cycle begins again. Cardiac output (CO) is a measurement of the amount of blood pumped by each ventricle (stroke volume) in one minute. This is calculated by multiplying the stroke volume (SV) by the beats per minute of the heart rate (HR). So that: CO = SV x HR. The cardiac output is normalized to body size through body surface area and is called the cardiac index. The