1,721,116 research outputs found

    sj-pdf-1-wso-10.1177_17474930211059608 - Supplemental material for Estimating nocturnal stroke onset times by magnetic resonance imaging in the WAKE-UP trial

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    Supplemental material, sj-pdf-1-wso-10.1177_17474930211059608 for Estimating nocturnal stroke onset times by magnetic resonance imaging in the WAKE-UP trial by Bastian Cheng, Hans Pinnschmidt, Alina Königsberg, Eckhard Schlemm, Florent Boutitie, Martin Ebinger, Matthias Endres, Jochen B Fiebach, Jens Fiehler, Ivana Galinovic, Robin Lemmens, Keith W Muir, Salvador Pedraza, Josep Puig, Claus Z Simonsen, Vincent Thijs, Anke Wouters, Christian Gerloff and Götz Thomalla in International Journal of Stroke</p

    sj-pdf-1-wso-10.1177_17474930211058012 - Supplemental material for Rivaroxaban versus aspirin for prevention of covert brain infarcts in patients with embolic stroke of undetermined source: NAVIGATE ESUS MRI substudy

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    Supplemental material, sj-pdf-1-wso-10.1177_17474930211058012 for Rivaroxaban versus aspirin for prevention of covert brain infarcts in patients with embolic stroke of undetermined source: NAVIGATE ESUS MRI substudy by Mukul Sharma, Eric E Smith, Lesly A Pearce, Kanjana S Perera, Scott E Kasner, Byung-Woo Yoon, Sebastian F Ameriso, Josep Puig, Dorte Damgaard, Jochen B Fiebach, Keith W Muir, Roland C Veltkamp, Roland C Veltkamp, Danilo S Toni, Nikolay Shamalov, Rubens J Gagliardi, Robert Mikulik, Stefan T Engelter, Daniel Bereczki, Martin J O’Donnell, Feryal Saad, Ashkan Shoamanesh, Scott D Berkowitz, Hardi Mundl, Robert G Hart and On behalf of the NAVIGATE ESUS MRI Substudy Investigators in International Journal of Stroke</p

    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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    die Suche nach genauen Prognosen von Gewebeschicksal in akutem ischämischen Schlaganfall

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    In perfusion magnetic resonance imaging a manual approach to delineation of regions of interest is, due to rater bias and time intensive operator input, clinically less favorable than an automated approach would be. We have compared the performances of these approaches, testing the hypothesis that automated protocols suffer from numerous artifacts which result in a false estimation of hypoperfused tissue. An additional goal of our study was to find a minimally biased yet maximally useful perfusion post‐processing protocol which could offer the treating physician an estimate of tissue fate. Methods One hundred and eighty‐four patients were included in this study, of which 39 control patients with neither a fresh infarction visible nor a final diagnosis of stroke and 145 patients with a confirmed diagnosis of acute ischemic stroke. Using three different software packages (Perfscape/Neuroscape, PMA and Stroketool) maps of mean transit time (MTT), cerebral blood flow (CBF) and Tmax were created. Three different thresholds were applied on each parameter map and subsequent volumes of hypoperfused tissue were calculated using both a manual and an automated protocol. Results The median difference between the automatically and manually derived volumes was up to 210 ml in Perfscape/Neuroscape, 123 ml in PMA and 135 ml in Stroketool. Correlation coefficients between perfusion volumes and radiological and clinical outcome were much lower for the automatic volumes than for the manually derived ones. Using the manual approach in patients with a persistent vessel occlusion a CBF map with a restrictive threshold had shown volumes of tissue at definite risk of infarction in up to a 100% of patients. The additional use of a CBF map with a high threshold had enabled identification of patients without penumbra. Conclusions The agreement of the automated and manual method was very poor, with the automated use producing falsely exaggerated volumes of hypoperfused tissue. No one combination of software, map and threshold was able to give a reliable estimate of tissue fate. However in patients with a vessel occlusion, a combination of a CBF map with a low threshold and a high threshold can provide a calculation of the minimum volume of brain tissue inevitably to be lost if the occlusion persists.In der Perfusions-Magnetresonanztomografie ist ein manueller Ansatz zur Abgrenzung von Schlaganfallarealen auf Grund der Bias der Begutachter und der dafür benötigten Zeit klinisch weniger geeignet als eine automatisierter Ansatz. Wir haben die Leistungen dieser beiden Ansätze verglichen, um zu beweisen, dass automatisierte Protokolle zahlreichen Artefakten produzieren, die zu einer falschen Einschätzung des hypoperfundierten Gewebes führen. Ein weiteres Ziel unserer Studie war, eine optimierte und am wenigsten voreingenommene Perfusionsbildgebungsverarbeitungsmethode zu finden, die dem behandelnden Arzt eine Einschätzung über das Schicksal des Gewebes bieten könnte. Methodik Hundertvierundachtzig Patienten wurden in die Studie aufgenommen, davon waren 39 Kontrollen, die weder einen frischen Infarkt noch eine endgültige Diagnose von Schlaganfall hatten und 145 Patienten mit einer bestätigten Diagnose von akutem ischämischen Schlaganfall. Drei verschiedene Software-Pakete (Perfscape / Neuroscape, PMA und Stroketool) wurden benutzt um Karten von â mean transit timeâ (MTT), zerebralen Blutflusses (CBF) und Tmax zu erstellen. Drei verschiedene Schwellenwerte wurden für jede Parameterkarte definiert. Anschließend wurden unter der Verwendung sowohl eines manuellen als auch eines automatischen Protokolls Volumina des hypoperfundierten Gewebes berechnet. Ergebnisse Die mittlere Differenz zwischen den automatisch und manuell ermittelten Volumen war bis zu 210 ml in Perfscape / Neuroscape, 123 ml in PMA und 135 ml in Stroketool. Korrelationskoeffizienten zwischen Perfusionsvolumina und radiologischen und klinischen Outcome waren viel geringer für die automatische als für die manuelle Methode. Bei Patienten mit einem persistierenden Gefäßverschluss konnte mit den manuell erstellten CBF Karte mit einem restriktiven Schwellenwert vom Untergang bedrohtes Risikogewebe in bis zu 100% der Patienten identifiziert werden. Die zusätzliche Verwendung einer CBF Karte mit einem hohen Schwellenwert ermöglichte darüber hinaus die Identifizierung von Patienten ohne Penumbra. Zusammenfassung Die Übereinstimmung zwischen der automatisierten und der manuellen Methode war sehr schlecht. Die automatisierte Methode überschätzte die Volumina des hypoperfundiertes Gewebes stark. Keine Kombination von Software, Karte und Schwellenwerten konnte eine zuverlässige Abschätzung des Gewebeschicksals bieten. Jedoch kann bei Patienten mit initialem Gefäßverschluss durch die Kombination einer CBF Karte mit einem niedrigen Schwellenwert und einem hohen Schwellenwert eine Berechnung des minimalen Volumens des gefährdeten Hirngewebes gewährleistet werden

    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
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