1,720,954 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

    Bayesian codon models for detecting convergent molecular adaptation

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    Modéliser le jeu combiné de la mutation et de la sélection au niveau moléculaire représente un des objectifs majeurs des sciences de l’évolution. L’acquisition massive de séquences génétiques au cours des dernières années a fourni un matériel abondant pour de telles analyses empiriques. Les modèles à codons sont de plus en plus utilisés en vue de fournir une description réaliste des processus de substitution des séquences codant pour les protéines. Parmi eux, les modèles mécanistes paramétrisent de façon séparée les effets mutationnels et sélectifs qui se combinent au sein du processus substitutionnel. Ces approches mécanistes caractérisent les effets sélectifs en s’appuyant sur un modèle explicite du paysage de fitness auquel la séquence protéique est soumise. Toutefois, jusqu’à présent, le paysage de fitness a toujours été considéré comme constant, alors qu’il existe des situations empiriques pour lesquelles le paysage de fitness subit en réalité des fluctuations écologiques au cours du temps. Lorsqu’une information empirique est par ailleurs disponible, concernant des différences systématiques de pression de sélection en fonction des fluctuations environnementales, il est alors possible de modéliser explicitement ces modulations du paysage de fitness. Nous avons développé un modèle à codons mécaniste, dont le but est de détecter ces effets sélectifs différentiels dépendant des conditions environnementales. Ce modèle a été implémenté dans un cadre d’inférence bayésienne, et a tout d’abord été appliqué au cas de l’évolution du VIH. Le VIH évolue sous la pression du système immunitaire de son hôte humain. Notre modèle de sélection différentielle (DS) décrit les mécanismes détaillés de l’évolution du VIH sous les contraintes induites par le fond génétique de l’hôte (par exemple, le HLA). De ce fait, il permet de trouver des associations entre adaptations du virus et profil HLA des hôtes. À long terme, notre approche permettra une meilleure compréhension du phénomène d’échappement du virus à la surveillance immunitaire de l’hôte, ce qui fournira alors des informations utiles en vue de l’élaboration d’un vaccin efficace contre le SIDA. Nous avons également appliqué notre modèle au gène de la Rubisco, une enzyme responsable d’une étape majeure de la photosynthèse. L’évolution de la Rubisco semble montrer des différences systématiques entre plantes dites C3 et C4, différences liées à des changements environnementaux. En utilisant le modèle DS, nous avons mis en évidence des effets systématiques d’adaptation convergente au niveau moléculaire, chez les espèces C4, par rapport aux espèces C3. Finalement, nous avons contrasté les résultats obtenus avec le modèle DS sur cet exemple avec ceux fournis par les modèles à codons classiques, basés sur l’estimation du dN/dS. Cette analyse comparée nous permet d’illustrer une différence conceptuelle fondamentale entre ces deux types de modèles à codons, concernant le type de régime sélectif que chaque type de modèle cherche à caractériser: à savoir, sélection directionnelle, contre adaptation continuelle.Modeling the interplay between mutation and selection at the molecular level is one of the primary goals in molecular evolution. Massive acquisition of genetic sequence data in recent years has provided a wealth of information for such empirically-driven studies. Codon-based models are increasingly used to give a realistic description of the substitution process in protein-coding genes. Among them, the mechanistic codon-based modeling approach distinctly parameterizes mutational and selective effects bearing on the overall substitution process. These mechanistic approaches characterize the selective pressure by relying on an explicit model of the amino acid fitness landscape over the sequence. Thus far, a constant fitness landscape has generally been assumed. Yet, there are some situations in which the fitness landscape experiences some environmental fluctuations through time. When the empirical knowledge about the systematic difference in selective pressures is available, regarding the fluctuating environment, it is possible to explicitly model condition-specific amino acid fitness modulations. In this thesis, we developed a codon-based model to capture these differential condition-specific selective effects on coding sequences. This model was implemented in a Bayesian framework and was first applied to HIV, which evolves under the selection pressure of the host immune system. Our Differential Selection (DS) model describes the detailed mechanisms of evolution of HIV under the constraints defined by host genetic backgrounds (e.g., Human Leukocyte Antigen). Therefore, it is possible to find associations between specific viral adaptations and specific HLA alleles of the hosts. Ultimately, our approach will enable us to understand better how the virus escapes from the host immune response, which will, in turn, provide a useful guideline for designing an efficient vaccine against AIDS. We also applied the DS model on Rubisco, an enzyme responsible for a major step in photosynthesis. The evolution of Rubisco has been shown to be different in C3 and C4 plants, as a consequence of differing environmental conditions. We used the DS model to reveal the consistent patterns of convergent adaptation in Rubisco in C4 plants, compared to C3 plants. Finally, we contrasted our results from DS model with those obtained under classical codon models based on the estimation of dN/dS. This comparative analysis allows us to illustrate a fundamental conceptual difference between these two types of codon models, which are meant to detect different selective regimes: directional selection versus ongoing adaptation

    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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    Nao informado

    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

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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