1,720,982 research outputs found

    The interaction between mesic and steppe grasslands: syntaxonomical, ecological and phytogeographical aspects.

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    The object of the study is mesic and steppe grasslands and their syntaxonomical, ecological and phytogeographical interactions. The territory of Lithuania is in an ecotone between two biomes. The vegetation formed in such geographical coverage should be characterized by a higher diversity of plant species in the communities and a mosaic of different combinations of species. Research on the diversity and structure of such communities is important at the continental scale. Our results showed that mesic and steppe grasslands could belong to two vegetation classes (Molinio-Arrhenatheretea and Festuco-Brometea), four alliances (Cynosurion, Deschampsion, Arrhenatherion, and Bromion), and 10 associations. Elenberg indicator values were used to identify the most important environmental gradients. We discovered out that the occurrence of steppe grasslands in the area is determined by local thermal conditions. Average annual air temperatures are 2–2.5 ° C higher than values typical of the Lithuanian climate. Short-term abandonment resulted in the loss of plant species and functional diversity. According to one of the phytogeographical features, the composition of phytocoenons is supported by a degree of oceanicity. The developed expert system of mesic and steppe grasslands classifies about 99% of vegetation plots

    Trumpalaikio apleidimo poveikis pusiau natūralių žolynų struktūrai ir funkcijoms.

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    A study of the impact of short-term abandonment on the structure and functions of semi-natural dry grasslands in Lithuania was performed. Data on the abundance of vascular plant species, hay and litter samples were collected. At the same time, plant functional traits and Ellenberg indicator values were used to evaluate the effect of abandonment on the structure and functions of semi-natural dry grasslands. The results showed that litter layer was significantly heavier in unmanaged plots compared to that in managed plots. The vascular plant species pool was higher in managed plots, where 62 vascular plant species were identified, while in unmanaged plots 46 species were identified. The species richness was significantly higher in managed semi-natural dry grasslands. Unmanaged plots had 12.3 ± 0.6 species, while managed plots had 17.7 ± 1.2 species per one square metre. Functional plant traits were similar in mowed and abandoned communities, while functional diversity was lower in unmanaged communities. These results are a clear indicator that the managing of semi-natural dry grasslands creates heterogeneity of the environment

    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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