1,720,972 research outputs found

    Cellulolytic and dextranolytic Gram‐negative bacteria: revival of the genus Cellvibrio

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    Blackall, Linda L., Hayward, A.C. & Sly, L.I. 1985. Cellulolytic and dextranolytic Gram‐negative bacteria: revival of the genus Cellvibrio. Journal of Applied Bacteriology59, 81–97. Nine bacterial strains were isolated from rhizosphere soils by enrichment in a defined mineral salts medium containing either cellulose or dextran as the sole carbon source. These and 17 reference strains, including representatives of two species of the invalid genus Cellvibrio, were characterized on morphological, biochemical and physiological properties. Numerical analyses were performed on the results using two different measures of similarity and methods of clustering. Eight of the nine isolates, three unnamed reference strains and the strains of Cellvibrio showed a high level of similarity and comprised a single cluster in both methods of analysis. The salient properties of strains in this cluster were: Gram‐negative, aerobic, slender rods, some having a slightly curved axis; mixed flagellation; oxida‐tive metabolism of glucose; extensive hydrolytic ability on complex polysaccharides; production of curdlan polysaccharide on glucose. Revival of the genus Cellvibrio (Winogradsky 1929) gen. nov., with an amended description and a new type species Cellvibrio mixtus sp. nov. is proposed. Copyrigh

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    Taxonomic note: V. B. D. Skerman (1921-1993), a reforming force in bacterial systematics and nomenclature

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    Professor V. B. D. Skerman made major contributions to the reform of bacterial systematics which are now in place and appreciated. He was the catalyst and a driving force for a series of reforms which led to the clarification of bacterial nomenclature. He reorganized the International Committee on Systematic Bacteriology and the Judicial Commission by persuading the members to accept and develop the statutes that govern their operations and also persuaded them to adopt a new starting date for bacterial nomenclature. The resulting revision of the International Code of Nomenclature of Bacteria and the publication of the Approved Lists of Bacterial Names under his direction leave a legacy of procedures for the orderly progress of bacterial taxonomy and nomenclature

    The use of disposable gaas generating kits for the growth of hydrogen-oxidizing bacteria and the determination of hydrogen autotrophy

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    A simplified procedure for the determination of autotropic growth of hydrogen-oxidizing bacteria has been developed. The method uses commercially available disposable hydrogen and carbon dioxide kits, commonly used in anaerobic bacteriology, to produce a gaseous atmosphre containing by volume approximately 41% hydrogen, 6% carbon dioxide, 11% oxygen and 42% nitrogen. The atmosphere was suitable for the growth of strains assigned to the species Alcaligenes eutrophus, Alcaligenes paradoxus, Paracoccus denitrificans, Pseudomonas facilis, Pseudomonas flava, Pseudomonas palleronii, Pseudomonas saccahrophilia and Rhodococcus sp. ('Nocardia opaca'). The method can also be used for the screening of hydrogen-oxidizing ability in bacterial isolates, thus eliminating the need for complex gas mixing devices or expensive gas mixtures

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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