1,720,962 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Processus oscillatoires lors de l'agrégation et la fragmentation des fibres amyloïdes.
Get PDFThe objective of this thesis is to study the physical process of protein aggregation and fragmentation. More specifically,oscillatory kinetic phenomena are identified during this process and are the subject of an in-depth analysis.The process of protein aggregation and fragmentation is intimately linked to the contraction and developmentof a vast class of incurable neurodegenerative diseases, amyloid diseases. Our work focuses on prion diseases, asubcategory of amyloid diseases, caused by the misfolding of protein conformation and the aggregation of thesemisfolded proteins into fibrils.First, our study focuses on experimental static light scattering data (SLS). The signals obtained correspond approximatelyto the second moment of the size distribution of amyloid fibrils in vitro and therefore provide informationon the evolution of the size distribution over time. We note damped oscillations at specific locations on the signals.These oscillations highlight the presence of complex, underlying kinetic phenomena during protein aggregation/fragmentation processes.The analysis of SLS signals leads us to build a parametric characterization of oscillations in the frequency domain(Fourier domain). We propose a numerical procedure to obtain these parameters. Then, we build a statistical testof hypotheses. We thus obtain a p-value that allows us to quantitatively assert the presence of oscillations in theexperimental signals.In a second step, we introduce and mathematically analyze a kinetic model of proteins capable of generating oscillations.The model is a variant of the polymerization/depolymerization system and considers two species of monomers:a pathological monomer that polymerizes and a healthy monomer that depolymerizes. Unlike traditional models,depolymerization is catalytic and non-linear and an exchange phenomenon occurs between the two species ofmonomers and polymers. The model combines a Lotka-Volterra system for monomers with a growth/fragmentationsystem: Becker-Döring in the discrete size setting, Lifshitz-Slyozov in the continuous size setting. In the discrete sizemodel, the oscillations are damped and under certain conditions we prove the exponential convergence towards astationary state. While in the continuous model, the system oscillates perpetually or converges to a Dirac dependingon the shape of the reaction coefficients.By complexifying the model, in particular by integrating other species of polymers and kinetic reactions, it is possibleto achieve a realistic modelling of protein kinetic processes. The mathematical study of these models leads to newinteresting problems, improves and clarifies the understanding of the underlying physical phenomena.Cette thèse a pour objectif l’étude du processus physique de l’agrégation et la fragmentation des protéines. Plusparticulièrement, des phénomènes cinétiques oscillatoires sont identifiés durant ce processus et font l’objet d’uneanalyse approfondie. Le processus d’agrégation et de fragmentation de protéines est intimement lié à la contractionet au développement d’une vaste classe de maladies neurodégénratives incurables, les maladies amyloïdes. Notretravail se focalise sur les maladies à prions, une sous-catégorie des maladies amyloïdes. Les maladies à prions ontpour cause le changement de conformation de protéines et l’agrégation de ces protéines sous forme de fibres.Dans un premier temps, notre étude porte sur les données expérimentales de diffusion statique de la lumière (SLS).Les signaux obtenus correspondent approximativement au moment d’ordre 2 de la distribution de taille des fibresamyloïdes in vitro. Ils renseignent sur l’évolution en temps de la distribution de taille. Des oscillations atténuées etlocalisées à des endroits spécifiques sur les signaux sont observables. Ces oscillations mettent en avant la présence dephénomènes cinétiques complexes, sous-jacent, lors des processus d’agrégation/fragmentation de protéines.L’analyse des signaux SLS nous mène à construire une caractérisation paramétrique des oscillations dans le domainefréquentiel. Nous proposons ensuite une procédure numérique pour obtenir ces paramètres. Puis, nous construisonsun test statistique d’hypothèses. Nous obtenons ainsi une p-valeur renseignant de manière quantitative sur laprésence d’oscillations dans les signaux expérimentaux.Dans un second temps, nous introduisons et analysons mathématiquement un modèle cinétique de protéinescapables d’engendrer des oscillations. Le modèle est une variante du système de polymérisation/dépolymérisationet considère deux espèces de monomères : un monomère pathologique qui polymérise et un monomère sain quidépolymérise. Contrairement aux modèles traditionnels, la dépolymérisation est catalytique et non-linéaire. Unphénomène d’échange opère entre les deux espèces de monomères et les polymères. Le modèle couple un systèmeLotka-Volterra pour les monomères à un système de croissance/fragmentation : Becker-Döring dans le cas discret entaille, Lifshitz-Slyozov dans le cas continu. Nous étudions le comportement en temps long de ces deux systèmes.Dans le modèle discret en taille, les oscillations sont atténuées et sous certaines conditions il y a convergence vers unétat stationnaire. Alors que dans le modèle continu, le système oscille de manière soutenue ou converge vers un Diracen fonction de la forme des coefficients de réactions. En complexifiant le modèle, en particulier en intégrant d’autresespèces de polymères et de réactions cinétiques, il est possible d’aboutir à une modélisation réaliste des processuscinétiques de protéines. L’étude mathématique de ces modèles conduit à de nouveaux problèmes intéressants,améliore et précise la compréhension des phénomènes physiques sous-jacents
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn 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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