By evolutionary adaptation to the perpetual day-night changes in envi- ronmental conditions, eukaryotic organisms have acquired an endogen- ous programme. This mechanism exhibits the characteristics of a self- sustaining oscillation the period of which approximates that of the earth's rotation. For animals such a property was first clearly demon- strated by Maynard S. Johnson (1939) who recorded, in constant conditions, free-running activity rhythms of white-footed mice (Peromyscus /eucopus). Johnson concluded from his observations that "this animal has an exceptionally substantial and...

This volume contains the papers presented at the symposion on Central Neurone Environment and the Control Systems of Breathing and Circulation held at Bochum, October 5-7,1981 in honour of Prof. Dr. Dr. h.c. Hans H. Loeschcke, who retired in March 1981. His discovery of ventral medullary substrates forming an essential drive for the ventilatory as well as for circulatory control systems, and the elaboration of this concept during the last 25 years have profoundly influenced the concepts in this field. In an age of proceeding specializa tion on partial mechanisms, his approach has always...

The aim of this symposium was to provide a framework for fruitful discussion on intestinal transport, not only for advanced scientists but also for younger people starting in this field of research. Invited lectures, communications and poster presentations were focused on four central themes, all treating the prop erties of the sole intestinal epithelium, deliberately leaving aside problems dealing with more integrative functions of the whole intestine. The importance of motility or blood circulation, for instance, is certainly capital in the overall intestinal function, but these aspects by...

The articles in this volume are based on papers presented at the International Symposium in Bad Neuenahr November 29 - December 1, 1982. The meeting was directed by H. Frohlich and was sponsored by IBM Deutschland through its Science and Education Programs Department. Contents Coherence in Biology H. Frohlich . Coherent Excitations and Raman Effect F. Drissler and L. Santo (With 4 Figures) 6 The Non-thermal Effect of Millimeter Wave Radiation on the Puffing of Giant Chromosomes F. Kremer, C. Koschnitzke, L. Santo, P. Quick, and A. Poglitsch (With 4 Figures) 10 Nonthermal Resonant Effects of...

During the last decade, the study of behavioural endocrinology has gone through a very exciting phase. New technologies have appeared which have allowed us to answer new questions; the present book is a reflection of this progress. In the eariy1970's, the advent of steroid radioimmunoassays (RIA) for the first time permitted measurement of gonadal and adrenal steroids in small aliquots of plasma. It thus became possible to measure these hormones repeatedly in the same animals (Le., to undertake longitudinal studies) and also to assay them in small-sized animals such as the rat or the ring...

RNA in Phylogenetic Studies of Eukaryotes L. STOCKLEIN, W. LUDWlG, K. H. SCHLEIFER, and E. STACKEBRANDT. . . . . . . . . . . . . . . . . . . . . . . . . . . . ."

Until some years ago serum or crude tissue extracts were used pre dominantly or exclusively as media supplements for the cultivation of cells. However, during this time evidence accumulated that these sup plements could not provide in an optimal way most of the cultivated cells with all factors necessary for their survival, their prolifer ation and/or differentiation. Moreover, a variety of cells could not be cultivated at all under these conditions and often the composition of the cultures changed within rather short periods of time by overgrowth of initially present subpopulations of those...

The German Society of Cybernetics organizes international conferences on selected interdisciplinary topics in regular 3-year intervals. The aim of these meetings is to bring together scientists who work in quite different disciplines, but are confronted with related problems and use the same or similar approaches. The topic of the 1983 conference which was held on March 23-25 at the University of Tiibingen came from a typical field of research in which engineers, biologists, and phYSicists share a common interest. We do not want to discuss here in detail the common principles which are used...

During the last decade it has become clear that bacteria-plant interactions play an important role in agricultural science. In particular, symbiotic nitro gen fixation, plant tumorigenesis, and plant pathogenic bacteria have been extenSively investigated. Therefore, several of my colleagues suggested the importance of organizing a specialized symposium on the "Molecular genetics of the bacteria-plant interaction." This symposium was held in Germany, at the University of Bielefeld, in the autumn of 1982. The International Program Advisory Board, together with the National Organizing Committee,...

This volume contains the papers presented at a symposium on popula tion biology sponsored by the Deutsche Forschungsgemeinschaft. It was . held at the guest house of the University of Ttibingen at Oberjoch on May 15-19, 1983. Prior to this conference a small group of European biologists had met in Berlin (June 1981) and Pavia (September 1982) to discuss re search problems on the borderline between population genetics and evolutionary ecology. From the contributions and discussions at these meetings it became evident that the unification of approaches to evolutionary problems in population...