Control of Energy Exchange

The intention of the authors of the present monograph in the field of thermal physiology has been to present briefly an analytic and authoritative treatment of the significant highlights that concern the exchange of energy between man and his thermal environment. The book is written for medical and graduate students as well as biophysicists and biomedical engineers. The text is consolidated into six chapters and four appendixes. A systems approach is used throughout the text. The first three chapters deal with energy production; specifically, food intake, normal body weight and composition, oxygen consumption, conversion of food to energy, the metabolic endocrines, and finally, energy expenditures across cell membranes. The last three chapters are all quite different. The fourth, titled "Thermophysiology," covers the physics of heat transfer from the body core to the skin by conduction and blood flow and from the skin to the environment by conduction (through clothing), radiation , convection and evaporation. The fifth chapter and perhaps the most thorough in the book is a review of the various changes in body temperature observed in health and disease and of the thermoceptive areas in the skin periphery and in hypothalamus that supply the necessary sensory input for regulation of body temperature. A control engineers' approach is used in presenting their postulated and observed relationships between the sensory and effector systems (vaso-dilation,-constriction, sweating, panting, shivering and behavioral change). The sixth and last chapter deals with adaptation to heat and cold. This subject area to which the authors themselves have made a major contribution usually gets little attention in reviews of temperature regulation. The authors have made liberal use of models to illustrate the various systems discussed. Their chapters are profusely illustrated with figures taken from classic experiments in the literature; e.g., Furusawa, Hill, Long and Lupton's oxygen requirement and uptake during work (1925), Hardy and Dubois' comparative heat exchange curves for men and women (1938), Brody's chart on the influence of environmental temperature on the heat production of various animals (1945), Scholander's relationship between body insulation and animal fur thickness (1950), Benzinger's relationship between sweating and tympanic temperature when modified by skin temperature (1955). The authors were quite thorough in searching out novel charts buried in the literature-e.g. D. M. Shames', "Theoretical Study of the Blood Glucose System," a prize M.D. Thesis at Yale in 1965. The appendices will prove valuable for those interested in advanced research in thermal …