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THE WORK OF I. M. GEL'FAND IN BIOLOGY

I. M. Gel'fand began to give his attention to biology in 1958. Up to 1960— 1961 this work was of a theoretical character: Gel'fand conducted a small seminar in which actual investigations of the physiology of movements and the physiology of the heart were examined. The first work of physiology carried out by Gel'fand and Tsetlin ended this period. It was devoted to an analysis of the propagation of activity in nerve fibres and the heart muscle, which were considered as continuous media. The theory developed in this article was used as a further stimulus for a whole series of investigations of the propagation of activity in various excitable structures. It must be observed, however, that this was Gel'fand's only work in physiology, as this term was accepted at that time: well chosen experimental material was suitable for the existing mathematical apparatus. Gel'fand's work in biology had only just begun.