1,720,958 research outputs found

    Visual illusions as potential enrichment tool for captive fish.

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    The purpose of the thesis is to develop new effective tool for the enrichment of fish, an animal that is increasingly used in several areas of our society: from the food sector to the field of scientific research. These animals, along with the ones kept as pets, live their life in captivity, a condition that could lead to serious suffering and health consequences. After an initial overview of the cognitive abilities of fish, to better understand the complexities of a mind so different from ours, and a panoramic on the legislations and ethic perspectives regarding the life of captive fish, the experimental section tackles two main aspects of the enrichment, necessary to improve the conditions of well-being: the physical and the social enrichment. In the two sets of experiments, some promising results indicate the possibility of using visual illusions as an effective enriching tool to improve the life of captive fish and at the same time to study their perceptual systems

    Shortest path choice in zebrafish (Danio rerio)

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    : Many animals regularly move between different locations within their home range. During these journeys, individuals are expected to use the shortest path, because this strategy minimizes energy expenditure and reduces exposure to adverse conditions, such as predation. The ability to find the shortest distance route has been demonstrated in ants, migrating birds and a few mammals. We investigated whether a freshwater fish, Danio rerio, exhibits this ability. Small groups of zebrafish were allowed to move between the two compartments of their tank using two paths differing in length. They developed a preference for the shorter path gradually over the six days of the experiment. Subjects' accuracy in choosing the shorter path varied from below 60%, with a 20% length disparity, to 80% when one path was twice as long as the other. In a second experiment, zebrafish were initially allowed to practice in groups and then tested individually. We found evidence of individual and sex differences in performance, with males performing more accurately than females. However, due to our experimental design, we cannot conclusively determine whether these differences are indeed cognitive or influenced by confounding factors during the group phase of the experiment

    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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