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    Pathophysiology of pressure ulcer in skeletal muscle

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    L’escarre est une pathologie liée à l’immobilité des patients, accidentelle ou associée à des comorbidités. Les premières lésions apparaissent dans le muscle avant de se développer en plaie cutanée sans que les mécanismes physiopathologiques de cette atteinte ne soient encore connus. L’objectif principal de cette thèse était d’identifier des voies de signalisation intervenant de manière précoce dans le développement des escarres au travers d’une étude transversale. Nous formulons l’hypothèse qu’une compression musculaire induit une altération de l’homéostasie calcique musculaire par atteinte des canaux calciques du réticulum sarcoplasmique (les récepteur de la ryanodine de type 1, RyR1) conduisant à la lésion du tissu musculaire et une inflammation du tissu sous-cutané.Sur un modèle animal de compression de 2 heures, à 100 mmHg, nous avons identifié une initiation des voies apoptotiques et une augmentation du stress oxydant des muscles de la paroi abdominale. Le RyR1 y est hyper-nitrosylé et hyper-oxidé et sa protéine régulatrice, calstabin1 se dissocie sous l’action de ce remodelage, ce qui entraîne une fuite calcique du réticulum sarcoplasmique vers le cytosol. Cette dysfonction n’est pas réversible à 3 jours post-compression mais il est possible de la prévenir en traitant les souris avec un rycal qui bloque la déplétion de la calstabin1. En clinique, chez une cohorte de patients paraplégiques, porteurs d’escarres, nous avons identifiés un remodelage du RyR1 dans les muscles paralysés (comparaison intra patient avec une biopsie saine) et une hypoxie des tissus sous la lésion médullaire. La dissociation de la calstabin1 au RyR1 a pu être corrélée à la pression moyenne et maximale exercée sur la peau de la zone sacrée du patient allongé en regard du muscle biopsié.Ce travail de thèse a permis de préciser les voies de signalisation intervenant de manière précoce dans le développement des escarres dans le muscle squelettique. Une compression mécanique induit une augmentation du stress oxydant, un remodelage du RyR1 et une dysfonction du canal à cause de la perte de l’interaction RyR1/calstabin1. Ces résultats ouvrent des perspectives intéressantes sur des traitements préventifs pharmacologiques et de suivi non-invasif qui permettront de retarder l’apparition des premières lésions musculaires.Pressure ulcer is a pathology related to patient immobility, which can be either accidental or incidental to comorbidities. The first damage are located in muscle tissue before developing in cutaneous breakdown per an unclear pathophysiology. The core objective of my PhD was to identify the early signaling pathways involved in pressure ulcer development, through a transversal study. We hypothesized that muscle compression will induce a calcium imbalance in muscles by a dysfunction of calcium channels from the sarcoplasmic reticulum (Ryanodine receptor isoform 1, RyR1) which will lead to muscle damage and sub-cutaneous inflammation.Mice model of a 100 mmHg, 2 hours compression of abdominal muscles was used to identify the apoptotic pathway initiation and a rise of oxidative stress. RyR1 is hyper-nitrosylated and hyper-oxydated thus this remodeling induces depletion of RyR1 stabilizing protein, calstabin1, and the resulting leaky phenotype increases intracellular calcium concentration. This channel functional impairment was not reversible up to 3 days post-compression but it was possible to prevent it through rycal treatment, protecting the binding calstabin1/RyR1. In a clinical trial, we identified from a paraplegic population with existing pressure ulcers, a RyR1 remodeling in paralyzed muscles (intra patient comparison with a healthy muscle biopsy) and a hypoxia of tissues below the spinal cord injury. Calstabin1 dissociation was correlated to the mean and peak pressure intensity of interface pressure applied over the sacrum skin of the bedridden patient directly above the biopsy location.This thesis project focused on early signaling pathways participating in pressure ulcer in skeletal muscle. A mechanical strain induces an increase of the intracellular redox state, post translational RyR1 modifications and a channel dysfunction because of calstabin1 depletion. The significance of my work is to propose both pharmacology and non-invasive monitoring solutions to prevent first muscle damage in pressure ulcer development

    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

    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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