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Mayer (F.). — Weltatlas. Erdôl und Erdgas. 1976, deuxième édition
No full textLerat Serge. Mayer (F.). — Weltatlas. Erdôl und Erdgas. 1976, deuxième édition. In: Cahiers d'outre-mer. N° 118 - 30e année, Avril-juin 1977. p. 201
Cytoskeletons in prokaryotes
No full textNot only eukaryotes, but also prokaryotes possess a cytoskeleton. Tubulin-related bacterial protein FtsZ, and actin-related bacterial proteins MreB/Mbl have recently been described as constituents of bacterial cytoskeletons. Genes coding for MreB/Mbl could only be found in elongated bacteria, not in coccoid forms. It was speculated that constituents of today's eukaryotic cytoskeleton (tubulin, actin) may have evolved from prokaryotic precursor proteins closely related to today's bacterial proteins FtsZ and MreB/Mbl. Prior to the description of proteins MreB/Mbl, evidence had been obtained for the existence of a shape-preserving cytoskeleton ubiquitously present in all bacteria. In the meantime, structural studies allow to speculate on a possible role of bacterial elongation factor Tu (EF-Tu) as a structural element in such a "cytoskeletal web". EF-Tu was long known to form fibrillar structures in vitro; now experimental data accumulate, pointing towards formation of intracellular protofilaments containing EF-Tu, and networks thereof as well. In addition, results of these structural studies suggest a so far unknown mode of complex formation of EF-Tu with active ribosomes: ribosomes/polysomes were seen to be attached to intracellular protofilaments. Implications for the understanding of EF-Tu-ribosome interaction, and a role of such a kind of putative protofilaments as a general site of attachment for cellular functional macromolecules are discussed. The notion is discussed that an EF-Tu-containing cytoskeletal web might have been the "primary" or "basic" kind of prokaryotic cytoskeleton, already in existence prior to the "invention" of precursors of today's MreB. (C) 2003 Elsevier Science Ltd. All rights reserved
[Stammbuch Friedrich Mayer] / F. M. W. P.
Full text link[STAMMBUCH FRIEDRICH MAYER] / F. M. W. P.
[Stammbuch Friedrich Mayer] / F. M. W. P. ( - )
Cover ( - )
Beschreibung ([0]-[1])
Register über sämtliche hierinn befindliche Nahmen. ([2]-[3])
Schilter, Zacharias; Blatt 1 (0v 1r)
Weinrich, Georg; Blatt 2 (1v 2r)
Becker, Cornelius; Blatt 3 (2v 3r)
Wirth, Michael; Blatt 4 (3v 4r)
Romanus, Franz; Blatt 5 (4v 5r)
Heidenreich, Elias; Blatt 6 (5v 6r)
Tancke, Joachim; Blatt 7 (6v 7r)
Gütler, Balthasar; Blatt 8 (7v 8r)
Schmuck, Vincentius; Blatt 9 (8v 9r)
Reuden, Ambrosius; Blatt 10 (9v 10r)
Stromer, Johann; Blatt 11 (10v 11r)
Albinus, Johannes; Blatt 12 (11v 12r)
Meurer, Christoph; Blatt 13 (12v 13r)
Fomann, Ortolph; Blatt 14 (13v 14r)
Arumäus, Dominicus; Blatt 15 (14v 15r)
Schröter, Philipp Jacob; Blatt 16 (15v 16r)
Welsen, Jacob; Blatt 17a (17a)
Decius, Johann Friedrich; Blatt 17b (17b)
Eyser, Christoph; Blatt 18a (18a)
Breitenhiller, Bartholomäus; Blatt 18b (18br)
Mornauer von Liechtenwerd, Wolfgang Theodor; Blatt 18bv (18bv-19r)
Soyer, Georg; Blatt 19 (18bv-19r)
Feyertager, Johann Wilhelm; Blatt 20 (19v 20r)
Reschlin, Georg; Blatt 22 (21v 22r)
Knorr, Martin Clemens; Blatt 23 (22v 23r)
Zuber, Matthaeus; Blatt 24 (23v 24r)
Rhem, Georg Friedrich; Blatt 25 (24v 25r)
Ruland, Valentin; Blatt 26 (25v 26r)
Trigell, Johann Jobst; Blatt 27 (26v 27r)
Schoenbach, Johann; Blatt 28 (27v 28r)
Avenarius, Johann; Blatt 29 (28v 29r)
Volland von Vollandseck, Johann Ludwig; Blatt 30 (29v 30r)
Weiß, Johann Leonhard; Blatt 31 (30v 31r)
Agricola, Andreas; Blatt 32 (31v 32r)
Agricola, Caspar; Blatt 33 (32v 33r)
Oppenrieder, Manasses; Blatt 34 (33v 34r)
Rauch, Christoph; Blatt 35 (34v 35r)
Strasser, Ludwig; Blatt 36 (35v 36r)
Schön, Michael; Blatt 37 (36v 37r)
Müller, Johann; Blatt 37v (37v 38r)
Murhard, Heinrich; Blatt 38 (37v 38r)
Lyttich, Johann; Blatt 39 (38v 39r)
Hoffmann, Georg; Blatt 40 (39v 40r)
Schröter, Johann; Blatt 41 (40v 41r)
Wachs, Johannes; Blatt 42 (41v 42r)
Zeck, Friderich; Blatt 43 (42v 43r)
Stromeier, Georg; Blatt 44 (43v 44r
The bacterial cytoskeleton and its putative role in membrane vesicle formation observed in a gram-positive bacterium producing starch-degrading enzymes
No full textBacteria may possess various kinds of cytoskeleton. In general, bacterial cytoskeletons may play a role in the control and preservation of the cell shape. Such functions become especially evident when the bacteria do not possess a true wall and are nevertheless elongated (e.g. Mycoplasma spp.) or under extreme cultivation conditions whereby loss of the entire bacterial cell wall takes place. Bacterial cytoskeletons may control and preserve the cell shape only if a number of preconditions are fulfilled. They should be present not only transiently, but permanently, they should be located as a lining close to the inner face of the cytoplasmic membrane, enclosing the entire cytoplasm, and they should comprise structural elements (fibrils) crossing the inner volume of the cell in order to provide the necessary stability for the lining. Complete loss of the cell wall layers had earlier been observed to occur during extensive production of bacterial starch-degrading enzymes in an optimized fermentation process by a Gram-positive bacterium. Even under these conditions, the cells had maintained their elongated shape and full viability. Which of the various kinds of bacterial cytoskeleton might have been responsible for shape preservation? Only one of them, the primary or basic cytoskeleton turns out to fulfil the necessary preconditions listed above. Its structural features now provided a first insight into a possible mechanism of formation of membrane blebs and vesicles as observed in the Gram-positive eubacterium Thermoanaerobacterium thermosulfurogenes EM1, and the putative role of the cytoskeletal web in this process. Copyright (C) 2003 S. Karger AG, Basel
Karpenstein, U./Mayer, F. C. (Hrsg.), EMRK : Konvention zum Schutz der Menschenrechte und Grundfreiheiten ; Kommentar / [rezensiert von] Katharina Pabel
No full textRezensiertes Werk: Karpenstein, U./Mayer, F. C. (Hrsg.): EMRK. Konvention zum Schutz der Menschenrechte und Grundfreiheiten ; Kommentar. - C. H. Beck, 2012. - 733 S. - ISBN 978-3-406-60812-
Structural organization of the intact bacterial cellulosome as revealed by electron microscopy
No full textThe architecture of the intact cellulosome Of Clostridium thermocellum, a huge extracellular multi-polypetide bacterial enzyme complex engaged in degradation of cellulose, was investigated by electron microscopy. This was done because former electron microscopic studies aimed at elucidation of the structure of polycellulosomes and cellulosomes were restricted by the fact that data on macromolecular details could only be derived from deformed or disrupted enzyme complexes, or by application of cryo preparation and imaging techniques yielding insufficient resolution. The shape of well-preserved cellulosomes was more or less spherical. often similar to that of an olive fruit with a cavity. Therein, multiple fibrillar structures could be visualized, interpreted to be the proximal stretches of copies of the fibrillar protein Cip A ('scaffoldin'), the nonenzymatic scaffolding protein known to function as attachment site for the enzymatic subunits, as well as fibrillar parts of anchoring proteins. The enzymatic subunits were depicted to be attached, in a repetitive fashion, to the distal stretches of the Cip A proteins. The enzymatic subunits were seen, in the intact cellulosome, to form a shell-like complex substructure surrounding the cavity. Obviously, this kind of architecture makes sure that the catalytic domains of the enzymatic subunits are exposed to the environment, and, hence, to the substrate, the cellulose fibrils. Attempts were made to demonstrate the alternating occurrence of coiled domains and fibrillar stretches along the elongated protein Cip A previously characterized by sequencing, X-ray, and NMR studies. To this end, Cip A molecules, with adhering enzymatic Subunits. were partially removed from their native location within the cellulosome, "stretched" by hydromechanical forces directly on the electron microscopic support film, negatively stained, and depicted by electron microscopy. The alternating occurrence of presumed coiled domains and fibrillar stretches along Cip A could be visualized, together with detached enzymatic subunits found on the support film. (C) 2003 Elsevier Ltd. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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