1,721,053 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
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
Modélisation des oscillations hippocampiques saines et épileptiques
No full textL'hippocampe peut présenter différents rythmes oscillatoires au cours du cycle veille-sommeil, chacun étant impliqué dans des processus cognitifs. Par exemple, des oscillations thêta-gamma sont produites pendant la veille et sont associés à la navigation spatiale et la mémoire à court terme, tandis que des complexes sharp-wave-ripples, produits durant les périodes de sommeil lent profond, jouent un rôle important dans la consolidation de la mémoire. Des modèles existent pour reproduire chacun de ces rythmes, cependant les mécanismes impliqués dans leur génération et les transitions entre eux ne sont pas encore parfaitement compris. Cette question est d'autant plus importante qu'une altération des rythmes hippocampiques est impliquée dans l'épilepsie du lobe temporal médian phamaco-résistante, une forme courante d'épilepsie qui ne peut pas être contrôlée par les traitements médicamenteux existants. Des modèles ont aussi été développés pour reproduire des crises d'épilepsie ou des pointes intercritiques, mais ces modèles ne parviennent pas à expliquer entièrement les liens entre les conditions neuropathologiques de l'hippocampe, des processus physiologiques comme le cycle veille-sommeil, et les oscillations qui en résultent. Dans ce contexte, l'objectif principal de cette thèse est d'apporter une meilleure compréhension de diverses oscillations hippocampiques, tant physiologiques que pathologiques. Pour ce faire, nous développons tout d'abord un modèle computationnel de l'hippocampe sain incluant au total plus de trente mille neurones Hodgkin-Huxley, représentés par des dizaines de milliers d'équations différentielles résolues numériquement, et comprenant une estimation du potentiel extracellulaire (LFP) généré par les neurones dipolaires tel que mesuré par une électrode macroscopique afin d'être plus facilement interprété. Nous effectuons ensuite une étude complète de l'activité de notre réseau basée sur des plans d'expérience afin d'étudier le rôle des paramètres intrinsèques du modèle et l'importance de la stimulation en entrée dans la production de différents rythmes couplés. Par la suite, notre modèle est évalué dans un contexte réaliste: l'activité qu'il génère quand il est soumis à des entrées réalistes est comparée avec des enregistrements intracérébraux obtenus sur des patients épileptiques. Nous montrons ainsi que notre modèle est capable de générer des oscillations de veille ou de sommeil similaires aux signaux cliniques sur le plan temporel et fréquentiel. Nous relions les modifications de paramètres du modèle (gains synaptiques et conductances de canaux ioniques) à une modulation cholinergique, et montrons comment les dynamiques des neurones influencent principalement les oscillations basse fréquence, tandis que la connectivité fonctionnelle contrôle les oscillations haute fréquence. Enfin, nous détaillons davantage notre modèle afin d'inclure quatre modifications de l'hippocampe observées dans les cas d'épilepsies du lobe temporal médian, à savoir la sclérose hippocampique, le bourgeonnement des fibres moussues, et une altération des dynamiques potassiques et chloriques (qui se traduisent par des modifications de la connectivité du réseau ou des paramètres des neurones individuels), et montrons comment ces mécanismes peuvent interagir avec le cycle veille-sommeil décrit précédemment pour donner lieu à des synchronisations et rythmes pathologiques. En conclusion, nous proposons dans cette thèse un modèle unique de l'hippocampe regroupant divers mécanismes précédemment décrits dans des travaux séparés, et analysons son activité oscillatoire tandis que nous varions différents paramètres représentant les propriétés structurelles et fonctionnelles du réseau, ainsi que des modifications pathologiques observées en épilepsie. Nos résultats apportent un nouvel éclairage sur les mécanismes impliqués dans la génération des oscillations hippocampiques, qui pourraient ouvrir la voie à de futures applications cliniques.The hippocampus can exhibit different oscillatory rhythms within the sleep-wake cycle, each of them being involved in cognitive processes. For example, theta-nested gamma oscillations, consisting of the coupling of theta and gamma rhythms, are produced during wakefulness and are associated with spatial navigation and working memory tasks, whereas sharp-wave-ripple complexes, consisting of fast oscillatory events occurring during low frequency waves, are produced during slow-wave sleep and quiet waking and play an important role in memory consolidation. Models exist to reproduce and explain the generation of each of these rhythms, yet the mechanisms involved in their generation and the transitions between them are not yet fully understood. This question is all the more important that altered hippocampal rhythms are involved in drug-resistant mesial temporal lobe epilepsy, a common form of epilepsy which cannot be controlled by existing pharmaceutical treatments. Some models have also been previously developed to reproduce epileptic seizures (episodes of excessive neural activity) or interictal discharges (brief peaks of synchronous activity), but these models cannot fully explain the links between neuropathological conditions of the hippocampus, physiological processes such as the sleep-wake cycle, and the resulting oscillations. In this context, the main objective of this thesis is to provide better understanding of various hippocampal oscillations, both physiological and pathological. To do so, we first design a full computational model of the healthy hippocampal formation including the entorhinal cortex, the dentate gyrus and the CA3 and CA1 regions. This model includes more than thirty thousand Hodgkin-Huxley point neurons, represented by tens of thousands differential equations to be solved numerically, as well as an estimation of the extracellular potentials (LFP) generated by the dipolar neurons as measured by a macroscopic electrode, so as to be more easily interpretable. We perform a thorough study of our model's activity based on design of experiments techniques to identify the role of each of its intrinsic parameters and the importance of input stimulation in the production coupled oscillatory outputs. We then evaluate our model in a realistic context : its activity under realistic input stimulation is compared with intracranial recordings obtained in epileptic patients. We demonstrate that our model is able to reproduce both sleep and wakefulness oscillations with temporal and frequential similarities with the clinically measured signals. We link the modification of some parameters of the model (synaptic gains and ion channel conductances) with cholinergic modulation, and show how single neuron dynamics are mostly responsible for the frequency of slow oscillations of our network, while network functional connectivity controls its fast oscillations. Finally, we detail our model further to include four pathological modifications of the hippocampus seen in mesial temporal lobe epilepsies, that is hippocampal sclerosis, mossy fiber sprouting, and impaired potassium and chloride dynamics in pyramidal neurons (which are modeled by changing the network connectivity or the parameters of individual neuron dynamics), and show how these mechanisms can interact with the previously described sleep-wake cycle and lead to pathological synchrony and rhythms such as seizures, interictal spikes and fast ripples. In conclusion, we propose in this thesis a unique model of the hippocampus regrouping many mechanisms previously described in separate works, and analyze its oscillatory activity as we vary different parameters representing either structural or functional properties of the network, as well as pathological modifications observed in epilepsy. Our results provide new insights into the mechanisms underlying the generation of various hippocampal oscillations, which could open the way to future clinical applications
- …
