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    Die pathophysiologische Rolle der Toll-like Rezeptor 2 Aktivierung in den neutrophilen Granulozyten in Patienten mit Akutem Koronarsyndrom mit intakter oder rupturierter fibröser Kappe

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    Die aktuelle Studie untersucht die pathophysiologischen Mechanismen, die hinter der zweithäufigsten Form des akuten Koronarsyndroms - Plaque Erosion stehen. Dabei ist der Fokus auf der Aktivierung der neutrophilen Granulozyten über den Toll-like Rezeptor 2 Signalweg gelegt.Background: Endothelial cell desquamation (ECD) due to inflammatory activation is one of the main pathophysiological features of acute coronary syndrome with intact fibrous cap (IFC-ACS, plaque erosion) (2, 5). The neutrophil granulocytes are the first immune cells to arrive at the coronary culprit lesion after ACS. Therefore, the current subanalysis of the OPTICO-ACS study aims to provide a better understanding of their molecular acti-vation patterns. Methods: Using optical coherence tomography (OCT) of the ACS-causing culprit lesion two groups (IFC-ACS vs. RFC-ACS) were generated, each consisting of thirty-two pa-tients matched by age, gender and diabetes mellitus type II. Local and systemic blood samples were collected from the site of the ACS-causing culprit lesion (LOC) and from the arterial sheath (SYS). Quantification of neutrophil counts and expression of activation markers was carried out by flow cytometry. MMP9 activity was assessed by fluorescence-based zymography. The combined effect of MMP9 and disturbed flow conditions were studied in an Ibidi flow chamber imitating coronary bifurcations. The direct cytotoxic ef-fects of TLR2 pre-activated neutrophils was examined in a co-culture with endothelial cells. Immunohistological staining of thrombus specimens characterized the expression of hyaluronidase 2 (HYAL2), an enzyme known to produce pro-inflammatory low molec-ular weight hyaluronan as one of the endogenous TLR2-ligands (9, 10). Results: Neutrophils of IFC-ACS patients show significantly higher expression of the toll-like receptor 2 (TLR2) in comparison to RFC-ACS-derived neutrophils, despite an equal cell count. Furthermore, the MMP9 plasma activity is significantly higher in local samples from IFC-ACS patients, indicating secretion and proteolytic activation of the enzyme dur-ing ACS. Local IFC-ACS- derived neutrophils increased their secretion and activity rates of MMP9 in response to TLR2-stimulation using Pam3CSK4, which was reversible after TLR2 blockade by a monoclonal neutralizing antibody. However, the combination of MMP9 and turbulent flow conditions leads to significant ECD. Furthermore, the TLR2-activation increases the survival of local IFC-ACS derived neutrophils, which induce higher rates of endothelial cell death in co-culture, independently of TLR2. Last but not least, IFC-ACS derived thrombi show higher expression of HYAL2 with subsequent higher local plasma concentration of hyaluronic acid as one of the main endogenous TLR2-ligands. Conclusion: By revealing novel local TLR2-dependant neutrophil activation patterns in IFC-ACS patients the current study provides new insights into the mechanism of plaque erosion. Moreover, the data suggest a crucial role of the hyaluronan metabolism in the endogenous activation of the TLR2 pathway in IFC-ACS. Further research is needed to assess the beneficial effects of a temporary TLR2-blockade in IFC-ACS and the possible application in secondary prevention

    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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