1,721,017 research outputs found
Renal stones composition in vivo determination: comparison between 100/Sn140 kV dual-energy CT and 120 kV single-energy CT
No full textThe objective of this study is to compare in vivo, the accuracy of single-energy CT (SECT) and dual-energy CT (DECT) in renal stone characterization. Retrospective study approved by the IRB. 30 patients with symptomatic urolithiasis who underwent CT on a second-generation dual-source scanner with a protocol that included low-dose 120 kV scan followed by 100/Sn140 kV dual-energy scan have been included. Stone composition was classified as uric acid, cystine or calcium oxalates, and phosphates according to attenuation values at 120 kV and to 100/Sn140 kV attenuation ratios and compared with the infrared spectroscopy analysis. 50 stones were detected in 30 patients. SECT correctly assessed stone composition in 52 % of the cases, DECT in 90 %. Sensitivity, specificity, positive predictive value, and negative predictive value in differentiating uric acid vs. non-uric acid stones were 0.94, 0.72, 0.64, and 0.96 for SECT and 1.00, 0.94, 1.00, and 0.96 for DECT, respectively. DECT significantly performs better than SECT in characterising renal stones in vivo, and may represent a useful tool for treatment planning
90-Day Mortality after Radical Cystectomy for Bladder Cancer: Prognostic Factors in a Multicenter Case Series
No full textObjectives: To identify preoperative risk factors for 90-day mortality and to validate existing nomograms in a multicenter series of patients undergoing radical cystectomy (RC). Materials and Methods: We evaluated 90-day mortality in 475 patients following RC and urinary diversion at 2 Italian institutions and validated Aziz and Isbarn nomogram. Univariable logistic models assessed the predictive ability of operative volume, age at intervention, gender, body mass index, carcinoma in situ at transurethral resection of the bladder, American Society of Anesthesiologist (ASA) score, Charlson Comorbidity Index, clinical stage and pathological stage (TNM). Results: Of the total number of patients, 387 of them (81%) were male. The median age at RC was 71.8. The most frequent ASA score was 2 (53%). Twenty-five deaths occurred within 90 days (5.3%), all among patients who had undergone RC and incontinent urinary diversion. Risk was higher in patients with advanced disease (OR 2.4); moreover, 90-day mortality odd in 70-79-year-old patients was 13 times higher than those of younger patients (<70). Predictive accuracy using Isbarn's and Aziz's nomogram were 67 and 71%, respectively. Conclusions: Our multicenter study confirmed the moderate predictive value of the Aziz nomogram. Larger studies are needed to improve on existing nomograms with the aim of enhancing preoperative counseling
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Kenntnisse von deutschsprachigen Urologen zur Häufigkeit der Assoziation des Peniskarzinoms mit dem Humanen Papillomavirus – Survey-Ergebnisse der European PROspective Penile Cancer Study (E-PROPS)
No full textZusammenfassung
Hintergrund Gemäß einer aktuellen Metaanalyse zeigt in Europa jeder zweite Patient mit einem Peniskarzinom (PeK) eine Assoziation mit dem Humanen Papillomavirus (HPV). Es liegen keine Daten darüber vor, inwieweit UrologInnen die Häufigkeit dieser viralen Karzinogenese kennen.
Methoden Es wurde ein 14-Items umfassender deutschsprachiger Survey erstellt und in Q3/2018 einmalig an UrologInnen von 45 Kliniken in Deutschland (n = 34), Österreich (n = 8), der Schweiz (n = 2) und Italien/Südtirol (n = 1) verschickt. Insgesamt waren nach vorher definiertem Qualitätsstandard 557 Fragebögen auswertbar (mediane Rücklaufquote 85,7 %). In dem Survey wurde u. a. nach der Häufigkeit HPV-assoziierter PeK in Europa gefragt und 4 Antwortmöglichkeiten vorgegeben: (A)-„ 50 – 75 %“, (D)-„kein Wissen über die Häufigkeit des Zusammenhangs“. Es wurde in der Auswertung eine Toleranz von 50 % akzeptiert, sodass B und C (25 – 75 %) als korrekte Antworten gewertet wurden. Mittels eines Bootstrap-korrigierten multivariaten logistischen Regressionsmodells wurden Kriterien identifiziert, die unabhängig eine richtige Antwort der Befragten vorhersagten.
Ergebnisse Die Kategorien A – D wurden von 19,2 % (n = 107), 48,8 % (n = 272), 12,9 % (n = 72) bzw. 19 % (n = 106) als Antwort gewählt, sodass der Endpunkt von 61,8 % (n = 344) der UrologInnen erreicht wurde (B + C). Die selbstständige Durchführung der Chemotherapie durch die Urologische Klinik (OR 1,55; p[Bootstrap] = 0,036) und die Anzahl der urologischen Klinikbetten (OR 1,02; p[Bootstrap] = 0,025) waren die einzigen Studienkriterien, die signifikant das richtige Ergebnis prädizierten. Der Status einer Universitätsklinik (p = 0,143), eine leitende Position der UrologInnen (p = 0,375) bzw. die jährliche Anzahl behandelter PeK-Patienten (p = 0,571) blieben hingegen ohne signifikanten Einfluss auf den Endpunkt.
Schlussfolgerung Unsere Studienergebnisse zeigen, dass sich deutschsprachige Klinik-UrologInnen der Häufigkeit einer gegenwärtigen HPV-Assoziation des PeK nur unzureichend bewusst sind
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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