Gesundheit und Ernährung: Die Macht der Kultur

Health and nutrition: The power of cultural patterns Despite enormous educational efforts and widely spread common knowledge about the subject, today's nutrition as it is practiced by many consumer groups concerning health in Germany, shows great potential to be optimized. On one side this is due to a cognitive dissonance: The knowledge about a healthy nutrition is opposed to a practice that is often detrimental to health. Among other factors, the main reasons for that phenomenon can be found within psychological aspects of nutrition: Practices that are tried and tested have a stabilizing effect and lead to emotional security. On the other side nutritional systems in principle change slowly and are difficult to control, especially since food itself and communicating about it function as ideological placings, as a representation of status or are matter of distinction in a society driven by modern lifestyles. Oftentimes supposedly reasonable nutritional practices hardly show any commonalities with these realities. Furthermore people who live in Germany but who were socialized with a different cultural background tend to have conceptions of a valuable nutrition that are often contradictorily to scientific findings. That also counts for people who obtain information from internet platforms that are not scientifically oriented. There they pick up superficial knowledge, esoteric beliefs or ideology‐based hints delivered through a science‐based appearance.     

Beiträge zur Pollenmorphologie der Iridaceae und ihre Bedeutung für die Taxonomie

Fifty-five genera of the Iridaceae were pollen morphologically investigated. The particularities stated in the apertures as well as the structure and sculpture of the exine are useful characteristics for the taxonomy of the family. On the base of the results of pollen morphological investigations and considering numerous further characteristics, a new arrangement of the Iridaceae is proposed.     

Die Bedeutung des Phytochroms für die Entwicklung der Kapazität für Photophosphorylierung

Die Entwicklung der Kapazität für Photophosphorylierung in den epi-gäischen Kotyledonen des Senfkeimlings wird durch Phytochrom (P_fr) reguliert. Wird der P_fr-Gehalt sehr niedrig gehalten, bildet sich keine Kapazität für Photophosphorylierung aus, auch wenn sich die Bildung von Chlorophyll normal vollzieht. Phytochrom (P_fr) kann die Kapazität für Photophosphorylierung nur dann ?induzieren”, wenn die Kotyledonen mit dem oberen Teil des Hypokotyls (Haken) verbunden sind. Hingegen ist die Chlorophyllbildung der Kotyledonen mit und ohne Haken gleich. Während sich der Effekt des P_fr auf die Kapazität für Photophosphorylierung relativ schnell (innerhalb von 15 min) ausprägt, ist der Effekt des P_fr auf die Chlorophyllbildung langsam. Er manifestiert sich erst etwa 2 h nach Lichtbeginn. Es wird der Schluß gezogen, daß die multiple Kontrolle von Piastidenfunktionen durch Phytochrom (P_fr) auf verschiedene, voneinander unabhängige Primärwirkungen des Phytochroms zurückzuführen ist. Mit Unterstützung der Deutschen Forschungsgemeinschaft (SFB 46). Wir danken Dr. E. Schäfer für die Bestimmung der Photogleichgewichte des Phytochromsystems bei Dichromatbestrahlung und Frau I. Schneider für gewissenhafte technische Mitarbeit.     

Ein neues System von Begasungsbrutschränken für die Biotechnologie

The experiences in the production of CO₂-incubators [1] have been the basis for the development of a system of gassing incubation cabinets, which, starting from a basic structure with temperature and humidity control (climatic test cabinets), consist of modular built up devices with regulating circuits for carbon dioxide and oxygen content of the incubation room atmosphere. The performance of the system is considerably extended by the equipment of the devices with a microcomputer system, by which the dynamic control of the parameters of the incubation room atmosphere is possible the first time. Essential mark of the system is further the standardized structural module for all devices and the flexibility in the equipment of the incubation room according to the demands of special tests.     

Fraktionierung von Inhaltsstoffen der Zuckerrübenmelasse,die toxisch für die Citronensäureproduktion mit Aspergillus niger sind

The toxic fractions were isolated from unsuitable molasses,not accepted for citrie acid fermentation. When the strains of A. niger: Z-208, R-8, P-16, R-65/4, all good producers of citric acid, were cultivated on the medium containing such molasses, the growth patterns were altered and the strains lost their acid-forming properties. After dialysis of the molasses samples fractions of low and high molecular weight were obtained but the latter had no effect neither on growth nor on fermentation patterns. The low molecular part, responsible for the toxicity of molasses against A. niger, was fractionated with Sephadex G-25. In such a way a low coloured fraction which inhibited the growth of A. niger strains could be separated. However there were no toxic compounds in the fractions with the highest values of absorbancy. The susceptibility of the strains,to some extent, depended on their ability for adaptation to the toxic fractions of molasses.     

Die Bedeutung der Haupt- und Nebenaugen für die photomenotaktische Orientierung der Trichterspinne Agelena labyrinthica (Cl.)1

Yawning in reptiles was investigated in field observations of various lizard and tortoise species and in laboratory experiments with the tortoises Testudo h. hermanni and Emys orbicularis. In the experiments the animals' reactions to various conditions of temperature, air O₂ and CO₂ content, fatigue and hunger, were tested. Yawning and related or similar motor patterns are described and discussed.     

Die Variabilität vegetativer und generativer Flechtenstrukturen und ihre Bedeutung für die Systematik

Die Entstehung von Stützleisten in den Thalli von Cladonia chlorophaea und Cetraria islandica, sowie die Entwicklung sekundärer Soredien im Inneren der Podetien von Cladonia chlorophaea werden beschrieben. Gemeinsam mit anderen Entwicklungsvorgängen von Flechten zeigen die Beobachtungen eine sehr geringe Determination der Flechtengewebe. Die Struktur wird weitgehend durch die Funktion bestimmt, während gleichzeitig bestimmte ontogenetische Abläufe unveränderbar sind. Die Bedeutung dieser Erscheinungen für die Systematik wird diskutiert.     

Rücken‐WNT für die Primärachse der Tiere

Axis formation in animals The last common ancestor of Cnidaria and Bilateria likely used the WNT/β‐Catenin pathway in a regionalized fashion to establish its primary, anterior‐posterior axis. Unexpectedly, the morphological head of Cnidaria corresponds to the rear end of Bilateria. Moreover, annelids use the WNT/β‐Catenin system for early, local and binary decisions, and insects developed a completely unrelated pathway. They use Bicoid (Drosophila) – or Hunchback/Orthodenticle (Tribolium) – to control axis formation. Nevertheless, WNT functions are essential during the segmentation phase in insects and in ancestral insects as well as in other arthropods during formation of posterior structures. In summary, the WNT/β‐Catenin system is an essential part of the molecular tool kit, which helped to establish the unique features of animals.