1,720,963 research outputs found

    Seed production of a subalpineFestuca nigrescens-Agrostis capillaris semi-natural grassland in the eastern Italian Alps

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    Studying the seed production of semi-natural grasslands helps to understand their regeneration processes and to evaluate the possibility of collecting seed useful for ecological restoration. In a subalpine Festuca nigrescens – Agrostis capillaris meadow, the development of the main grasses’ seed production and the standing seed yield at meadow maturity were studied. The inflorescence size was in the lower part of the variation range reported in previous studies. The seed viability was average to high and durable. The biological floret site utilization was mostly above 50%. With 458 fertile stems m22, the seeds produced (all seeds produced up to the time of the meadow maturity) by the main grasses were 21,000m22, of which 77% were of A. capillaris and 81% were viable.On a 3-year average, the standing seed yield (seeds present on the plants, i.e. produced minus shed seeds) at meadow maturity was 6953 seedsm22. Amount and composition of the produced seeds were affected mainly by the variability among years of the fertile stems density of the perennial grasses and the annual hemiparasite Rhinanthus freynii. The percentage of produced seeds which formed the standing seed yield was affected mainly by the collecting date

    Cerebellar Metabolism of Phosphatidylethanolamine and itsWater-Soluble Precursors During Bicuculline- InducedConvulsive Seizures

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    The incorporation of labeled ethanolamine into phosphatidylethanolamine (PE) and its water-soluble precursors, phosphoetanolamine and CDP-ethanolamine, is measured in rat cerebella during the course of bicuculline-induced convulsive seizures. The labeling of CDP-ethanolamine and phosphoethanolamine diminishes 6 min after the administration of both bicuculline and radioactive ethanolamine whereas that of PE is unaffected in these conditions. Time is very important to this effect; indeed, no differences of the labeling of PE water-soluble precursors can be found in rat cerebellum of normal and convulsing animals 12 min after the administration. The cerebellar pool of CDP-ethanolamine doubles after 6 min of convulsions, which means that unlabeled CDP-ethanolamine forms from a non-radioactive source, such as lipid, may be through the reversal of the ethanolamine phosphotransferase reaction. This effect disappears 12 min after the injection of the convulsant

    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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    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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