1,720,960 research outputs found

    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

    Crested porcupines (Hystrix cristata): mycophagist spore dispersers of the ectomycorrhizal truffle Tuber aestivum

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    Truffles, as hypogeous, ectomycorrhizal fungi, have no means to actively discharge spores into the environment and thus depend on mycophagists for spore dispersal. After consumption of fruiting bodies by animals and passage through the digestive tract, the spores are released in faecal pellets. Recently, in the Abruzzo region (Italy), Hystrix cristata has been spotted inside private truffières, but its role in spore dispersal has never been investigated. Here, we report our research on the occurrence of Tuber aestivum spores in porcupine's faecal contents in a truffière in L'Aquila, Italy, where a H. cristata specimen was photographed. The spores were isolated from faeces by using a suspension of 0.7 M ZnSO4. We also verified degradation and disfiguration of the digested spores' reticular ornamentation compared to that of fresh spores from ascomata collected inside the truffière, through measurements performed by scanning electron microscopy. A few truffle spores had germinated within the faeces

    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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    The role of wild boars in spore dispersal of hypogeous fungi

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    Wild boars (Sus scrofa L.) are well-known for soil disturbance in natural and cultivated truffières but their role in spore dispersal is poorly investigated. In the present work we studied the occurrence of hypogeous fungal spores in faecal contents of 14 wild boars randomly hunted in “Parco dei Gessi e Calanchi dell’Abbadessa” Regional Park (North of Italy) where truffle production has been previously investigated for three years. Six methods for spore analysis in faeces were compared and the suspension of faeces in ZnSO4 (70%) solution resulted to be the most reliable. Hypogeous fungal spores, including Tuber magnatum and Tuber aestivum spores, were detected in 9 animals. This result suggests that the detection of fungal spores in faeces of wild boars may provide information on the presence of hypogeous fungi in an area. However, the poor abundance of spores suggests that the wild boar can be considered an opportunistic mycophagist, ingesting truffles only occasionally, as a seasonal source of food. Considering the magnitude of wild boar movements during seasonal migrations, it is possible to speculate that they play a key role in truffle long distance dispersal

    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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