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Viele bedeutende Errungenschaften der modernen Biologie sind erst nach Erfindung und Amvendung von leistungsfahi, gen Methoden m6glich geworden. Man kann zwar nicht sagen, daB wir in einem "Zeitalter der Methoden" leben, aber jeder Schritt zur LOsung eines wichtigen biologischen Problems muJlte und mu.G durch die Entwicklung einer geeigneten Methode vorbereitet werden. Es gibt nicht viele "klassische" Verfahren, die sich in der physiologisch-c...

Organized by the International Academy of Astronautics and the International Astronautical Federation with the Support and Cooperation of UNESCO and the Scientific Cooperation of COSPAR

During the past three decades the organic chemist has become in­ creasingly used to take advantage of more and more complex instrumenta­ tion and physical measurements in lieu of laborious, time-consuming and often ambiguous chemical transformations. Mass spectrometry is perhaps the most recent, most complex and most expensive addition to this field. In view of the astonishingly quick acceptance of nuclear magnetic reso­ nance by the organic c...

v. Formation of negative ions by processes other than attachment in the gaseous phase at low X/po 17. Introduction. As early as 1912, J. J. THOMSON [32J in his first mass spectro­ graph observed negative ions of 0-, Cl-, H- and what he believed to be N-. He at first ascribed these to possible dissociation of polar gaseous compounds by electron impact but control studies using ionization at low energies in glow discharges indicated that this wa...

Depuis l'isolement de la creatine par CHEVREUL, en 1832, dans les extraits de viande (44) et son identification par LIEBIG, en r847, l'attention des biochimistes a porte principalement, pendant longtemps, sur le role de l'arginine dans la production de l'uree (I28), sur le cyde de l'ureo­ genese (I34) et sur celui de la phosphocreatine (7I) et de la phospho­ arginine (r68, I69) dans la contraction musculaire. A la suite de la mise en evidence,...

This volume grew out of the preparation and achievements of the Symposium organized by the Luxembourg Mathematical Society in June 1992, at Chateau Bourglinster (Luxembourg). We express our best thanks to Monsieur Marc Fischbach, ministre de I 'Education nationale, Luxembourg Monsieur Rene Steichen, ministre delegue aux Affaires culturelles, Luxem­ bourg, Academie des sciences, Paris, Academie roya1e des sciences, des lettres et des beaux-arts...

The properties of proteins are determined not only by the sequence of amino-acid residues in the polypeptide chains, but also by the con­ figuration of the chains-the way in which the chains are coiled or folded. It is probable that denaturation, the loss of some of the specific properties of a native protein, may in many cases be the result simply of a change in configuration of the polypeptide chains, without any change whatever in the seque...

Inadequate observation of sedimentary TRUSHKovA and KUKHARENKO'S "Atlas of structures has been responsible for incorrect Placer Minerals." The most comprehensive interpretation of the order of superposition atlas is the "Atlas of Textures and Struc­ in deformed beds and this has led, in turn, tures of Sedimentary Rocks" edited by A. to gross errors in stratigraphy and structure. V. KHABAKOV (1962). Failure to recognize and utilize those Our At...

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No detailed description available for "Eugène Scribe and the French Theatre, 1815-1860".

Ich wehre mich gegen eine Festlegung, ich will meine Arbeit nicht über einen persönlichen Stil definiert wissen, denn es geht in erster Linie nicht um mich. Es geht um einen der Sache angemessenen Stil. Insofern ist auch keine abschließende Kategorisierung möglich: Ist das künstlerisch oder ist das dokumentarisch? Die Fotografie hat sich verändert, sie ist befreit aus der rein dokumentarischen Arbeitsweise, auch wenn sie noch einen solchen Ans...

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Diese Ubersieht soll die wesentliche Literatur uber Ubichinon und einige chemisch nahe v:erwandte naturliche Chinone bis etwa Oktober 1961 referieren. Der Name Ubichinon (englisch Ubiquinone) wurde von MORTON und Mitarb. (II3) fUr eine Substanzgruppe der allgemeinen Formel (I) vorgeschlagen. In MORTONS Arbeitskreis wurde die betreffende Substanz anfanglich als "Substanz SA" bezeichnet (Io8). Wie sieh aus spateren o II H3CO", /~~CH3 3112 4 116 ...

The verrucarins and roridins are secondary metabolites of the soil fungi Myrothecium verrucaria (Albertini et Schweinitz) Ditmar ex Fries and Myrothecium roridum Tode ex Fries. The species Myrothecium belongs to the fungi imperfecti, order of Moniliales, family Tubercularia­ ceae (30, 17, 32). The distinction between these and other closely related fungal species is difficult. It has been studied and discussed by various authors (82, 16, 55, 7...

123 phase and hence have no direct bearing on the retention time of solutes. However in gas-solid chromatography, a considerable quantity of the mobile phase may be adsorbed on the surface of the stationary adsorbent which diminishes the column's effective length and ability to retain solutes. In this respect helium has been found to be preferable to most other gases (GREENE and Roy, 1957) because it is adsorbed to the least extent. 3. Packed ...

Sect 2. 317 tinuity surfaces 1. This suggests that a wake pressure Pw be associated with each flow past a bluff body, and that a wake parameter (2. 4) which plays the same role as the cavitation parameter (2. 1), be defined for the flow. This idea has been made the basis of a modified wake theory (ef. Sect. 11) which proves to be in good qu- titative agreement with pressure and drag measurements. It should be emphasized, however, that un­ h li...

The Committee of Neurotraumatology of the World Federation of Neurosurgical Societies decided to elaborate a Glossary of Neuro­ traumatology, and for this purpose appointed a subgroup of members of this Committee, headed by Dr. E. S. Gurdjian, whose report follows this preface. The main reason for the Committee's decision was the hope that the diffusion of the Glossary through "Acta Neurochirurgica" may bring about a better understanding of ne...

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Although the subject of wave propagation in solids has a long history, the classical theory of elastic waves having been developed in the nine­ teenth century by STOKES, POISSON, RAYLEIGH and KELVIN, the last two decades have seen a remarkable revival of interest in this subject among both theoreticians and experimenters. There' are a number of reasons for this, first, experimental methods for the generation and detection of high frequency mec...