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    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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    Hypoxiemarker im equinen Endometrium im klinisch-pathomorphologischen Kontext

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    Einleitung: Ein häufiger Befund in routinemäßig untersuchten Bioptaten equiner Endometrien sind degenerative Alterationen der Blutgefäße in Form von Angiosklerosen. Sie stellen die Ursache einer endometrialen Minderperfusion dar und bedingen Fruchtbarkeitsstörungen. Ziele der Untersuchungen: Der Inhalt dieser Arbeit war die Untersuchung equiner Endometriumproben mit graduell vari-ablen Angiosklerosen. Die Hypothese ist, dass degenerative Gefäßwandveränderungen die Ursache für einen hypoxischen Zustand darstellen. Anhand der Expression von so genannten Hypoxiemarkern sollte das Vorliegen eines potenziellen Sauerstoffmangels in Folge einer Minderperfusion durch degenerative Blutgefäßwandveränderungen überprüft und immunhis-tologisch dargestellt werden. Des Weiteren sollten Zusammenhänge zu anderen Einflussfak-toren wie zum Beispiel dem Zyklusstand, dem Vorliegen einer Trächtigkeit, dem Alter oder einer Endometrose untersucht werden. Tiere, Material und Methoden: Grundlage für diese Untersuchungen waren vor allem equine Endometriumbioptate aus der Routinediagnostik des Instituts für Veterinär-Pathologie. Anhand mittels Pikrosiriusrot gefärb-ter Bioptate wurden Gruppen ohne Alterationen von maximal 5-jährigen Maidenstuten (n = 10) sowie mit ausschließlich graduell variablen Angiosklerosen (jeweils n = 10 mit dezenter, geringgradiger, gering- bis mittelgradiger, mittelgradiger und mittel- bis hochgradiger sowie n = 8 mit hochgradiger Angiosklerose) gebildet. Des Weiteren wurden aus dem Sektionsgut des Instituts Endometriumproben von tragenden Stuten (n = 6), eine weitere Uterusprobe einer trächtig geschlachteten Stute, Bioptate mit gering- bzw. hochgradiger Endometrose in Kombi-nation mit gering- bzw. hochgradiger Angiosklerose (jeweils n = 6) und Bioptate, die an defi-nierten Zyklustagen (Östrus, früher bzw. später Diöstrus) entnommen wurden (jeweils n = 2) entsprechend graduiert. Alle Proben wurden nach erfolgreicher methodischer Etablierung der Antikörper gegen hypo-xia-inducible factor 1α (HIF-1α), Glucosetransporter 1 (GLUT1), vascular endothelial growth factor A (VEGF A) und vascular endothelial growth factor receptor 2 (VEGF-R2) hinsichtlich der Expression dieser Hypoxiemarker immunhistologisch untersucht. Für unterschiedliche Zellpopulationen (luminales Epithel und Zellen der Drüsenausführungsgänge, oberflächliche, mittlere und basale glanduläre Epithelzellen, Stromazellen) und die arteriellen und venösen Blutgefäße (jeweils getrennt nach Intima, Media und Adventitia) wurde markerweise der Im-munreaktive Score (IRS) aus jeweils 10 nebeneinander liegenden Gesichtsfeldern bei 400-facher Vergrößerung (Zellpopulationen) bzw. jeweils 5 Arterien, Arteriolen, Venen und Venulen bestimmt. Die statistische Untersuchung erfolgte mit dem Statistikprogramm SPSS 22 (SPSS Software-GmbH, München). Die Datenvisualisierung wurde mit GraphPad Prism 8 (Graphpad Software Inc., San Diego, Kalifornien, USA) durchgeführt. Ergebnisse: Eine Expression der Hypoxiemarker lässt sich in unterschiedlichen Zellpopulationen darstel-len. HIF-1α ist in nahezu allen Proben im luminalen Epithel, in den Drüsenepithelzellen und in Intima und Media von vor allem arteriellen Gefäßen nachweisbar. Ein nicht signifikanter Trend zu einem höheren IRS zeigt sich erst ab mittel- bis hochgradigen Angiosklerosen in den Drüsenepithelzellen. Demgegenüber lässt sich eine verminderte Expression in der Media von arteriellen Gefäßen erkennen, die für vier Angiosklerose-Gruppen auch statistisch signifikant ist. GLUT1 kann vor allem im Bereich des luminalen Epithels und der Zellen der Drüsenaus-führungsgänge sowie vereinzelt auch in Drüsenepithelzellen nachgewiesen werden. Die ins-gesamt graduell variable Expression sinkt tendenziell mit steigendem Angiosklerosegrad, al-lerdings nicht statistisch signifikant. VEGF A wird von nahezu allen untersuchten Zellpopulati-onen sowie Blutgefäßen und in nahezu allen Proben relativ konstant hoch exprimiert. Zu einer vermehrten Expression kommt es ab Vorliegen einer mittelgradigen Angiosklerose vor allem in den glandulären Epithelzellen, welche bei hochgradiger Angiosklerose auch als statistisch signifikant anzusehen ist. Eine VEGF-R2-Expression lässt sich ebenfalls vorrangig im glan-dulären und luminalen Epithel erkennen, wenngleich sie sich überwiegend geringgradig dar-stellt. Deutliche Unterschiede lassen sich hier in keiner untersuchten Zellpopulation erkennen. Im Zusammenhang mit einer Trächtigkeit zeigen sich Unterschiede in der Expression bei dreien der vier Marker im Bereich des luminalen Epithels und der Zellen der Drüsenausfüh-rungsgänge, also der Schicht, die an der Bildung der feto-maternalen Verbindung beteiligt ist. Im Vergleich zwischen normalen und endometrotischen Drüsen zeigen sich für alle Marker Unterschiede im Expressionsverhalten, die allerdings nicht statistisch signifikant sowie scheinbar unabhängig vom Angiosklerosegrad sind. Eine deutliche Zyklusabhängigkeit konnte nicht nachgewiesen werden. Schlussfolgerungen: Mittels der durchgeführten Untersuchungen wird deutlich, dass insbesondere schwere Angi-osklerosen für immunhistologisch darstellbare hypoxische Zustände sorgen. Ferner zeigen die eigenen Untersuchungen, dass sich die endometrialen Zellpopulationen hinsichtlich der Ex-pression der untersuchten Marker unterscheiden. Dabei wird außerdem deutlich, dass es nicht zwangsläufig zu dem erwarteten Anstieg der Expression der Hypoxiemarker kommen muss. Aus diesem Grund sollte zur Beurteilung des Vorliegens einer Hypoxie eine Untersu-chung der Expression mehrerer derartiger Marker erfolgen. Ein gänzlicher Ausschluss von anderen Einflussfaktoren als Hypoxie auf die Expression der untersuchten Marker kann im verwendeten Studienaufbau nicht erfolgen. Zukünftige Untersuchungen sollten zum einen einen größeren Probenumfang (insbesondere bei der Untersuchung anderer Faktoren als Angiosklerose) aufweisen sowie zum anderen weitere Hypoxiemarker umfassen. Die unter-suchten Marker spielen wahrscheinlich eine Rolle bei besonderen physiologischen (z. B. Trächtigkeit) als auch pathologischen Prozessen (z. B. Endometrose) im equinen Endometri-um und stellen somit interessante pharmakologische Targets zur positiven Beeinflussung der Reproduktionsleistung oder für die Therapie der equinen Endometrose dar.Introduction: Degenerative alterations of the blood vessels, especially angiosclerosis, are a common finding in equine endometrial biopsies. They are the cause of an insufficient endo-metrial blood supply and therefore result in fertility problems. Objectives: The subject of this thesis was the examination of equine endometrial specimens with variable degrees of angiosclerosis. The hypothesis is that degenerative changes of the vessel wall are the cause of a hypoxic environment. The presence of a potential lack of oxygen as a result of hypoperfusion because of degenerative changes in the blood vessels was assessed via im-munohistochemistry by examining the expression of so-called markers of hypoxia. In addi-tion, the possible relationship to other factors such as the stage of the estrous cycle, pregnan-cy, age or endometrosis was considered. Animals, material and methods: This study is based on equine endometrial biopsies submitted to the diagnostic service of the Institute of Veterinary Pathology. By the means of picrosirius red stain, biopsy groups without any alterations of maiden mares with a maximum age of 5 years (n = 10) as well as biopsies with solely gradually variable angiosclerosis (n = 10 with minimal, mild, mild to moderate, moderate and moderate to severe, as well as n = 8 with severe angiosclerosis, respecively) have been established. In addition, specimens of pregnant mares from necropsied (n = 6) and slaughtered (n = 1) horses, biopsies with mild and severe endometrosis in combination with mild and severe angiosclerosis (n = 6, respectively) and biopsies taken on certain days of the estrous cycle (estrous as well as early and late diestrous, n = 2, respectively) have been graduated likewise. After their successful methodical establishment, all specimens have been examined im-munohistochemically via antibodies against hypoxia-inducible factor 1α (HIF-1α), glucose transporter 1 (GLUT1), vascular endothelial growth factor A (VEGF A) and vascular endothe-lial growth factor receptor 2 (VEGF-R2) in regard to the expression of those markers for hy-poxia. The immunoreactive score (IRS) for each marker has been determined by examining 10 adjacent high-power fields (400-fold magnification) for the different endometrial cell popu-lations (luminal epithelium and cells of glandular ducts, superficial, mid and basal glandular epithelial cells, stromal cells), and 5 arteries, arterioles, veins, and venules, respectively, sepa-rated by intima, media and adventitia. The statistical analysis has been performed via data analysis software SPSS 22 (SPSS Software-GmbH, Munich). The visualisation of data has been done with GraphPad Prism 8 (Graphpad Software Inc., San Diego, California, USA). Results: Expression of the markers of hypoxia was demonstrated in different cell populations. HIF-1α could be detected in almost every specimen in the luminal and glandular epithelia as well as in the intima and media of blood vessels. A non significant trend towards increased IRS was observed in biopsies with at least moderate to severe angiosclerosis in the endometrial glands. In contrast, a diminished expression was identified in the media of arterial vessels, which was significant in four of the angiosclerosis groups. GLUT1 was detected in the luminal epithelium and the cells of glandular ducts as well as in some glandular epithelial cells. In total the ex-pression was variable, with a trend towards lower levels in cases with higher degrees of angi-osclerosis. VEGF A was constantly expressed on relatively high levels by all of the examined cell populations and blood vessels in almost all examined biopsies. There was a trend towards increased expression in cases with moderate angiosclerosis predominantly in the glandular epithelia, reaching statistical significance in endometrial biopsies which are severely altered by angiosclerosis. An expression of VEGF-R2 could be seen in glandular and luminal epitheli-al cells. Nevertheless, no distinct differences were evident. In endometrial specimens of pregnant mares, expressional differences could be identified for three out of the four examined markers, especially in the luminal epithelium and the cells of glandular ducts, which are involved in the development of the feto-maternal connection. The comparison of normal with endometrotic glands revealed a complex expression pattern of all four examined markers which seemed to be independent of the degree of angiosclerosis. A distinct difference in dependence of the phase of the estrous cycle could not be detected. Conclusions: The current study demonstrated that severe angiosclerosis is the cause of an immunohisto-chemically detectable hypoxic condition. Furthermore, this study showed systematic differ-ences in the expression of the examined markers for the different endometrial cell popula-tions. Notably, the employed markers of hypoxia did not always show the expected increase in parallel with increasing grades of angiosclerosis. For that reason, the expression of multiple markers of hypoxia should be assessed to demonstrate a lack of oxygen in tissue samples using immunohistochemistry. The used study design did not allow the complete exclusion of other factors influencing the expression of the examined markers. Therefore, future studies should contain a larger pool of specimens on the one hand (especially while examining other factors than angiosclerosis) and employ a panel of markers of hypoxia. The examined mark-ers seem to play an important role during physiological (e. g. pregnancy) as well as pathologi-cal processes (e. g. endometrosis) and by that might be rewarding pharmacological targets to positively influence reproduction or to possibly treat equine endometrosis

    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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