1,721,054 research outputs found

    Urban effects on timing and variability of diel activity differ across passerine species and seasons

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    Life on Earth is adapted to rhythmic cycles in environmental conditions throughout the day and year via diel patterns of behavioural activity. Urban conditions can disrupt such behavioural rhythms of activity. However, most studies so far have investigated urban effects on patterns of activity of single species in a single season. Additionally, we know little about the level of between- and within-individual variation in urban and non-urban populations, and whether they differ. Here, we use automated radio telemetry to record patterns of daily activity in six passerine species (blackbird, robin, great tit, blue tit, dunnock and chaffinch) across two urban and two forest populations during the pre-breeding and post-breeding seasons. We investigate urban effects on five activity-related traits: time of activity onset, time of activity end, duration of diurnal activity, level of diurnal activity and level of nocturnal activity. We employ statistical tools that allow us to estimate urban effects on mean phenotypic values but also quantify urban versus forest differences in between-individual and within-individual phenotypic variation. We found the strongest urban effects on time of activity onset in blackbirds and robins during both the pre- and post-breeding seasons: urban populations of blackbird and robin started their daily activity earlier than their forest counterparts. We did not find this effect in the other species. Urban populations of all species showed higher levels of nocturnal activity than forest populations, but this effect was not offset by lower diurnal activity, suggesting that urban birds may incur higher daily energetic demands. Lastly, our analysis revealed large and consistent differences in variation in the investigated timing traits. Onset and end of daily activity were more variable in urban birds between individuals, implying lower population synchronisation, and more variable within individuals, implying less consistent behaviour, than in their forest counterparts. Conversely, activity levels were more variable in forest birds. We conclude that, for birds, urban life is associated with less rest, less consistency and lower synchronicity, but that effect sizes depend on species and time of the year. Our results warn against generalising the effects of urbanisation on daily rhythms of birds and call for future studies to understand the mechanisms behind species and seasonal differences

    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

    Urban effects on timing and variability of diel activity differ across passerine species and seasons

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    1. Life on Earth is adapted to rhythmic cycles in environmental conditions throughout the day and year via diel patterns of behavioural activity. 2. Urban conditions can disrupt such behavioural rhythms of activity. However, most studies so far have investigated urban effects on patterns of activity of single species in a single season. Additionally, we know little about the level of between and within-individual variation in urban and non-urban populations, and whether they differ. 3. Here, we use automated radio telemetry to record patterns of daily activity in six passerine species (blackbird, robin, great tit, blue tit, dunnock and chaffinch) across two urban and two forest populations during the pre-breeding and post-breeding season. We investigate urban effects on five activity-related traits: time of activity onset, time of activity end, duration of diurnal activity, level of diurnal activity and level of nocturnal activity. We employ statistical tools that allow us to estimate urban effects on mean phenotypic values, but also quantify urban versus forest differences in between-individual and within-individual phenotypic variation. 4. We found the strongest urban effects on time of activity onset in blackbirds and robins during both the pre- and post-breeding seasons: urban populations of blackbird and robin started their daily activity earlier than their forest counterparts. We did not find this effect in the other species. Urban populations of all species showed higher levels of nocturnal activity than forest populations, but this effect was not offset by lower diurnal activity, suggesting that urban birds may incur higher daily energetic demands. 5. Lastly, our analysis revealed large and consistent differences in variation in the investigated timing traits. Onset and end of daily activity were more variable in urban birds between individuals, implying lower population synchronization, and more variable within individuals, implying less consistent behaviour, than in their forest counterparts. Conversely, activity levels were more variable in forest birds. 6. We conclude that, for birds, urban life is associated with less rest, less consistency, and lower synchronicity, but that effect sizes depend on species and time of the year. Our results warn against generalising the effects of urbanisation on daily rhythms of birds, and call for future studies to understand the mechanisms behind species and seasonal differences.Peer reviewe

    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

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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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