REGULATION AND CONTROL IN PHYSIOLOGICAL SYSTEMS.

The papers referred to here are grouped in the proceedings of the conference under the heading: Some Endocrinology and Metabolism. The first (Commentary) paper examines the application of systems theory to the study of physiological systems during the past twenty-five years with particular reference to endocrinology and metabolism. Some of the main directions which these applications have taken are outlined. Also, some of the more significant deficiencies (from a systems theory point of view) in such applications as they have appeared in the literature to date are pointed out, along with some of the reasons for these deficiencies. Several critical questions concerning the relevance of certain systems theoretic concepts and methods to the study of physiological systems are posed. Some suggestions as to how the current status of the application of systems theory to physiological systems might be improved are made. In particular, the need for, and importance of developing an effective thermodynamic theory of physiological systems based on appropriate variational principles and supported by a suitable underlying statistical mechanics, is discussed. Following is a list of titles and authors: Systems Theory Aspects of Physiological Systems. By Edwin B. Stear. Autoregulation of Chemotransport to Brain Tissue. By D. F. Bruley, H. I, Bicher, D. D. Reneau, and M. H. Knisely. Nonlinear Dynamic Properties of the Pancreas and Liver. By Richard N. Bergman and Richard J. Bucolo. Computer Analog of the Endocrine Pancreas. By T. G. Ewart, A. M. Albisser, B. S. Leibel, Z Davidovac, and W. Zingg. Analysis of Sex-Hormone Data in the Castrated Rat. By Louis M. Shotkin. Dynamic Study and Modelling of Pituitary-Adrenal Elements. By E. Papaikonomou.