1,720,957 research outputs found

    Syntaxonomical survey of Geranio-Cardaminetalia hirsutae: semi-natural therophytic vegetation of the Mediterranean Region.

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    A syntaxonomical scheme, including geographical range and synonymies of all the associations ascribed to Geranio-Cardaminetalia hirsutae, is presented. This order, framed into the class Stellarietea mediae, groups sciaphilo-subnitrophilous annual vegetation of natural and semi-natural habitats, commonly occurring on substrata rich in organic matter, accumulating on stone-walls, shaded rocks and initial soils, often under the canopy of shrubs and trees. Twelve new associations from Sardinia, Sicily, Egean islands and Israel are here described for the first time

    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

    A syntaxonomical survey of the Sicilian dwarf shrub vegetation belonging to the class Rumici-Astragaletea siculi

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    Basing on literature data and unpublished relevés from Sicily, a survey of the syntaxa belonging to the class Rumici-Astragaletea siculi Pignatti & Nimis 1980 em. Mucina 1997 (= Cerastio-Carlinetea nebrodensis Brullo 1984) is presented. The class groups orophilous plant communities dominated by dwarf- shrubs, often with a pulvinate and thorny growth form. The class is represented in Sicily by two orders: Rumici-Astragaletalia siculi Pignatti & Nimis 1980, including the sole alliance Rumici-Astragalion siculi Poli 1965, restricted to Mount Aetna, and Erysimo-Jurinetalia bocconei Brullo 1984, including two alliances: the acidophilous Armerion nebrodensis Brullo 1984 and the basiphilous Cerastio-Astragalion nebrodensis Pignatti & Nimis ex Brullo 1984. Within the class, nineteen associations have been recognized. Nomenclature, floristic settlement, ecology and chorology are examined for each syntaxon. The floristic autonomy of the class Rumici-Astragaletea siculi is examined from the phytogeographic viewpoint and is confirmed by numerical analyses including not only the Sicilian phytocoenoses, but also those occurring in Sila and Aspromonte (Calabria) and ascribed to the same class by Brullo, Scelsi & Spampinato 2001 and Brullo, Gangale & Uzunov 2004. It is, as well, highlighted that the Pollino massif represents the southernmost limit to the distribution range of the class Festuco-Brometea, whose southward expansion is hampered by the lack carbonatic highlands in the southernmost tip of the Italian Peninsula

    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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