Work of breathing When there is increased gas flow resistance, the optimal respiratory rate decreases. This work (generally during the inhalation phase) is stored as potential energy which is recovered during exhalation. A pressure difference is required to overcome the frictional resistance to gas flow due to viscosity, and to provide non-elastic components of movement of the airway tissues to accommodate pulmonary volume change. Total work done against non elastic forces is 35% of total. Work is defined as a force applied over a distance. The SI unit of work is the Joule, equivalent to a force of 1 Newton exerted along a
Department of Scientific and Industrial Research (United Kingdom) purposes. Large areas of research were the responsibility of other bodies - aviation, atomic energy, agriculture, health and medicine, meteorology - though it might undertake specific investigation on behalf of the responsible departments. The department encouraged and supported scientific research in universities and other institutions by means of grants for special research projects, research fellowships, studentships, grants to research associations and research contracts. The department absorbed or created a number of research organisations, which included large laboratories for special fields of work. Existing institutions for which it assumed responsibility were the National Physical Laboratory from the Royal Society in 1918,