1,721,014 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

    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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    Cooperative behaviour in naked mole-rats (Heterocephalus glaber): Specialized castes or social plasicity?

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    Master thesis - University of Veterinary Medicine Vienna - 2020In cooperatively breeding vertebrates, non-reproductive group members assist in rearing offspring that is not their own and perform a variety of cooperative tasks such as foraging, nest building, and group defence. Investment in these activities varies between individuals according to state-dependent changes in fitness costs and benefits. The most extreme form of cooperative breeding is found in eusocial insects, where cooperative labour is divided among non-breeders via task specialisation, which leads to the formation of morphologically distinct permanent castes or temporal (age-based) castes. Naked-mole rats (Heterocephalus glaber) were the first mammals to be described as eusocial. Large group size and high reproductive skew make them unique among mammals and may have led to the development of a highly specialised social organisation similar to that of eusocial insects. The aim of the study was to clarify whether non-reproductive colony members of naked mole-rats are organised in a rigid caste system of behavioural specialisation or whether they show social plasticity similar to other cooperatively breeding mammals. We collected observational and body mass data from five naked mole-rat colonies over several months and employed multilevel, multinomial regression models to investigate task specialisation and the distribution of body mass and cooperative behaviour. Non-breeders did not specialise on specific tasks and there were no trade-offs between different cooperative behaviours within individuals. Body mass did not predict cooperative behaviour expression and behavioural phenotypes as well as maximum body mass were continuously distributed, showing no signs of discrete functional or morphological castes. Repeatability of cooperative behaviour was low, suggesting behavioural plasticity similarly to other cooperatively breeding vertebrates. In sum, we found no evidence of a distinct caste system in subordinate naked mole-rats. To investigate the mechanisms responsible for the observed variation in behaviour, future research requires longitudinal data from individuals of known age throughout ontogeny as well as data from free-ranging mole-rats.Master thesis - University of Veterinary Medicine Vienna - 2020In cooperatively breeding vertebrates, non-reproductive group members assist in rearing offspring that is not their own and perform a variety of cooperative tasks such as foraging, nest building, and group defence. Investment in these activities varies between individuals according to state-dependent changes in fitness costs and benefits. The most extreme form of cooperative breeding is found in eusocial insects, where cooperative labour is divided among non-breeders via task specialisation, which leads to the formation of morphologically distinct permanent castes or temporal (age-based) castes. Naked-mole rats (Heterocephalus glaber) were the first mammals to be described as eusocial. Large group size and high reproductive skew make them unique among mammals and may have led to the development of a highly specialised social organisation similar to that of eusocial insects. The aim of the study was to clarify whether non-reproductive colony members of naked mole-rats are organised in a rigid caste system of behavioural specialisation or whether they show social plasticity similar to other cooperatively breeding mammals. We collected observational and body mass data from five naked mole-rat colonies over several months and employed multilevel, multinomial regression models to investigate task specialisation and the distribution of body mass and cooperative behaviour. Non-breeders did not specialise on specific tasks and there were no trade-offs between different cooperative behaviours within individuals. Body mass did not predict cooperative behaviour expression and behavioural phenotypes as well as maximum body mass were continuously distributed, showing no signs of discrete functional or morphological castes. Repeatability of cooperative behaviour was low, suggesting behavioural plasticity similarly to other cooperatively breeding vertebrates. In sum, we found no evidence of a distinct caste system in subordinate naked mole-rats. To investigate the mechanisms responsible for the observed variation in behaviour, future research requires longitudinal data from individuals of known age throughout ontogeny as well as data from free-ranging mole-rats.Masterarbeit - Veterinärmedizinische Universität Wien - 2020Nicht-reproduktive Mitglieder von Gruppen kooperativ brütender Wirbeltiere helfen bei der Aufzucht von Jungen, die nicht ihre eigenen sind, und verrichten eine Reihe an kooperativen Aufgaben wie Futtersuche, Nestbau und Gruppenverteidigung. Das Investment in diese Aktivitäten variiert zwischen den einzelnen Tieren mit vom individuellen Zustand abhängigen Veränderungen in Fitnesskosten und -vorteilen. Die extremste Form des kooperativen Brütens findet man in eusozialen Insekten, in deren Kolonien die kooperative Arbeit mittels Spezialisierung auf bestimmte Aufgaben zwischen den Nicht-Brütern aufgeteilt ist, was zur Bildung von morphologisch abgegrenzten, dauerhaften Kasten oder temporären, altersabhängigen Kasten führt. Der Nacktmull (Heterocephalus glaber) war die erste Säugetierart, die als eusozial beschrieben wurde. Die hohe Anzahl an Gruppenmitgliedern sowie der äußerst ungleiche Reproduktionserfolg in ihren Kolonien (reproductive skew) mögen zur Entwicklung einer hochspezialisierten sozialen Ordnung beigetragen haben, die der von eusozialen Insekten ähnelt. Das Ziel der Studie war es herauszufinden, ob die nicht-reproduktiven Mitglieder von Nacktmullkolonien in einem strikten Kastensystem mit Verhaltensspezialisierung organisiert sind oder ob sie sozial flexibel sind wie andere kooperativ brütende Säugetiere. Wir sammelten Beobachtungs- und Körpergewichtsdaten von fünf Nacktmullkolonien über mehrere Monate und verwendeten multilevel, multinomiale Regressionsmodelle, um Aufgabenspezialisierung und die Verteilungen von Körpergewicht und kooperativem Verhalten zu untersuchen. Nicht-Brüter spezialisierten sich nicht auf bestimmte Aufgaben und es gab keine Trade-offs zwischen verschiedenen kooperativen Verhaltensweisen innerhalb der Individuen. Verhaltensexpression war nicht abhängig vom Körpergewicht und Verhaltensphänotyp sowie maximales Körpergewicht waren stetig verteilt und ließen keine klar abgegrenzten funktionalen oder morphologischen Kasten erkennen. Die Wiederholbarkeit kooperativen Verhaltens war gering, was eine Verhaltensflexibilität ähnlich derer von kooperativ brütenden Vertebraten nahelegt. Zusammenfassend fanden wir keine Anzeichen für die Existenz eines strikten Kastensystems in nicht-reproduktiven Nacktmullen. Um die Mechanismen zu erforschen, die den beobachteten Verhaltensunterschieden zugrunde liegen, bedarf es weiterer Studien mit longitudinalen Daten von Tieren bekannten Alters sowie von freilebenden Nacktmullen

    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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