Zur Kenntnis des lamellaren Musters in ausgewachsenen und der Kristallgitterstruktur in jungen Chloroplasten

Summary (1) It is shown that in the chloroplasts ofChlamydomonas andAnthoceros thick, dense lamellae and thin, less dense lamellae alternate. (2) In the chloroplasts of many phanerogame plants with grana, thin less dense lamellae limit the parcel of thick grana-lamellae above and below. Since the differentiations 1 and 2 are present in the photographs of many publications (although not mentioned), it is suggested that this kind of lamellarmodel has often been overlooked until now. — The « Kristallgitterstruktur » has been found in a cryptogamous plant,Selaginella, in young chloroplasts, for the first time. The connection between the elementary particles of the crystal-lattice and the young lamellae has been verified again. — The possibility of formation of double lamellae by fusion of blastulae or tubuli is discussed in detail.     

Das Verhalten des Wasserstoffs in der Sonnenkorona

Ohne Zusammenfassung     

Der Magnesium- und der Zinkgehalt von Chloroplasten

Summary The Mg- and Zn-content was determined with atomic absorption in chloroplasts isolated with a new dry method byBehrens et al.     

Die Ringbinden als eine allgemeine unspezifische Reaktion der quergestreiften Muskulatur

Summary On the basis of the research of other workers, and of the author's own results, an attempt is made to conceive the «Ringbinden» as a commonly occurring, nonspecific form of reaction of striated muscle tissue.     

Das Ganzheitsproblem in der Biochemie

Ohne Zusammenfassung     

Das perfundierte Riesenaxon des Tintenfisches Eine neue Methode der Nervenphysiologie und ihre ersten Anwendungen

Summary The recently developed perfused nerve fibre technique, which consists of perfusing the interior of a squid giant fibre with artificial solutions, is described. The experimental results obtained with various perfusion fluids are discussed in relation to the theory of nerve excitation.     

Das Bild der heutigen Mathematik

Ohne ZusammenfassungAnsprache bei der feierlichen Rektoratsübergabe am 18. November 1954.     

Das mittlere Molekulargewicht der Sternmaterie

Summary On account of the electrostatical forces between the ions and electrons in the interior of a star, the mean molecular weight µ should be given a higher value than is usually assumed. It is believed that a satisfactory theoretical calculation of has not yet been given, and that it does not seem to be possible. The determinations of the chemical composition of the stars are regarded as shaky, because they are based on the value of .     

Das Virialtheorem in seiner Beziehung zu den mechanischen Grundlegungen des zweiten Hauptsatzes der Wärmelehre

Ohne Zusammenfassung Vorgelegt von S. Flügge P. Niedernberg zugeeignet     

Das Wachstum der Zellwand in synchronerChlorella

Summary By pulse labelling, it is shown that the relative growth rate of cell wall substances in synchronousChlorella has a sharp maximum at the time of autospore formation. The dependence on time of the rate of growth of the cell wall coincides with that of the rate of increase of the free space. Moreover, the increase of the nitrogen content of the cell wall also has a maximum roughly at the same time as the growth rate.     

Das bioelektrische Potential an der zytoplasmatischen Membran der Granulozyten

Summary The bioelectric potential between the interior of granulocytes taken from whole blood and exudatleucocytes and 2 extracellular media was examined with microelectrode-technique. The order of magnitude amounts to about – 5 mV. The potentials of the cell population are Gaussian distributed.

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Frl. D.Lüders sind wir für die sehr sorgfältig durchgeführten Zellpunktionen und Potentialmessungen sowie für die Herstellung der Mikroelektroden zu grossen Dank verpflichtet.     

Das Elektroretinogramm der isolierten Katzennetzhaut bei Zuwachsreizen

Summary The electroretinogram of the isolated cat retina in response to incremental stimuli was studied with varying intensities of background and/or stimulus. The results are explained in terms of known components.     

Das Spitzenwachstum der Fasern beiLinum perenne L

Summary In shoots ofLinum perenne apical growth was observed at both ends of the fibres. Their rounded tips, rich in protoplasm, protude into the middle lamellae of adjacent fibres or parenchyma cells. In addition to their apical growth, the fibre walls undergo symplastic growth with the walls of neighbouring cells. The formation of the pointed ends of fully developed fibres is described.     

Kristallgitterstruktur in den jungen Chloroplasten einer Dikotyledone

Summary The same periodical structure of the so-called primary granum, as found inChlorophytum, Aspidistra and other monocotyledons, is shown to be present in a dicotyledon also. There must exist a causal connection between that lattice and the development of the lamellar strom-grana pattern, as was first suggested byLeyon.     

Das apolaritäre Prinzip der Mittelfrequenz-Reizung

Ohne Zusammenfassung     

Das Chromosomenkomplement des Wildschweins (Sus scrofa)

Summary Wild pigs from Germany have 36 chromosomes with 4 pairs of acrocentrics. This is in accordance with the findings in European wild pigs from Tennessee (McFee et al.) but differs from those in the wild pig from Japan and in the domestic pig. Intraspecific Robertsonian changes and a preferential selection of the 38-chromosome-type in the course of domestication may be responsible for these variations.     

Das Eindringen des Vektorkalküls in die Differentialgeometrie

Zusammenfassung Die ersten Versuche, die Differentialgeometrie mittels Vektoren bzw. Quaternionen darzustellen, erzielten kaum irgendeine Resonanz. Die Autoren der klassischen Differentialgeometrie-Lehrbücher, Bianchi und Darboux machten keinen Gebrauch von Vektoren, ihrem Beispiel folgten die übrigen Lehrbuchautoren. Erst unter dem Eindruck von Einsteins allgemeiner Relativitätstheorie begann sich die Situation zu verändern, indem die Zusammenhänge zwischen Vektorkalkül und Tensorkalkül deutlich wurden. Die jüngere Generation von Differentialgeometern, allen voran Blaschke und Struik, verwenden in ihren Lehrbüchern die vektorielle Darstellungsweise als ein geradezu selbstverständliches Hilfsmittel. Vorgelegt von C. Truesdell