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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
Effect of different conditioning strategies on myocardial function and prognosis after ST-elevation myocardial infarction
No full textZiel:
Ziel der Arbeit war die umfassende Evaluation des kardialen MRT-basierten myokardialen Feature-Trackings (CMR-FT) in Bezug auf seine Reproduzierbarkeit, seine Anwendbarkeit zur Beurteilung kardioprotektiver Effekte unterschiedlicher Conditioning-Strategien auf die kardiale Funktion und seine Validierbarkeit zur Prognoseeinschätzung nach ST-Streckenhebungs-Myokardinfarkt (STEMI).
Material und Methoden:
Anhand der CMR-FT Analyse von zehn Probanden ohne relevante Einschränkung der links-ventrikulären Ejektionsfraktion (LVEF) und zehn Patienten mit signifikant eingeschränkter systolischer Funktion wurden zwei CMR-FT-Softwarelösungen (TomTec, Germany; QStrain, Netherlands) miteinander verglichen und der Effekt wiederholter Messungen auf die Reproduzierbarkeit untersucht. Erhoben wurden die links-ventrikulären Strainparameter globaler longitudinaler Strain (GLS), globaler circumferentieller Strain (GCS) und globaler radialer Strain (GRS).
Der Effekt unterschiedlicher Conditioning-Regime auf die kardiale Funktion wurde durch die Analyse der links-ventrikulären (GLS, GCS, GRS) und links-atrialen Strainparameter (total strain (ε(s)), passive strain (ε(e)) und active strain (ε(a)) sowie die links-ventrikulären Dyssynchronieparameter (die circumferential und radial uniformity ratio estimates CURE und RURE) der unterschiedlichen Interventionsarme der Randomized-LIPSIA-conditioning-Studie analysiert. Zudem wurde der Effekt eines gesteigerten myocardial salvage index (MSI) auf die links-ventrikuläre und links-atriale Funktion untersucht.
Im dritten Abschnitt wurde die externe Validierung etablierter Cut-off Werte links-ventrikulärer (GLS, GCS, GRS) und links-atrialer Strainparameter (ε(s), ε(e), ε(a)) sowie links-ventrikulärer Dyssynchronieparameter (CURE, RURE) für die verbesserte Prognoseeinschätzung nach akutem Myokardinfarkt durch Anwendung dieser Cut-off Werte und Analyse ihres prognostischen Mehrwerts gegenüber etablierten kardiovaskulären Risikofaktoren im Randomized-LIPSIA-conditioning-Kollektiv angestrebt.
Ergebnisse:
Der GLS und der GCS wiesen die geringste Inter-Hersteller-Variabilität und die beste Intra-Hersteller-Reproduzierbarkeit auf. Der GRS zeigte die höchste Variabilität aller CMR-FT-Parameter. Wiederholte Messungen steigerten zwar die Intra-Hersteller-Reproduzierbarkeit des GRS, unabhängig von der Anzahl der Messungen war der mit QStrain gemessene GRS jedoch signifikant höher als mit TomTec.
Unabhängig vom gewählten Conditioning-Regime konnte keine wesentliche Verbesserung der CMR-FT-basierten kardialen Mechanik gegenüber einer konventionellen Therapie mittels alleiniger perkutaner koronarer Intervention erreicht werden. Ein positiver Effekt einer Kombinationstherapie aus remote ischemic conditioning und postconditioning ließ sich nicht nachweisen. Hingegen konnten wir erstmals demonstrieren, dass der MSI signifikant mit einer besseren kardialen Funktion assoziiert ist. Ein Korrelat der kardialen Mechanik für einen größeren MSI ließ sich nicht nachweisen.
Die von Eitel, Schuster und Stiermaier et al. identifizierten Cutoff-Werte für den GLS, GCS, GRS, den links-atrialen Strain und den CURE konnten auch im Randomized-LIPSIA-conditioning-Kollektiv die Prognoseabschätzung signifikant verbessern. Anhand des GLS und der links-atrialen Funktionsparameter gelang zudem eine Risikostratifikation bei Patienten mit erhaltener links-ventrikulärer Ejektionsfraktion (LVEF). Der prognostische Mehrwehrt des ε(s) für die Gesamtmortalität zu der LVEF, der Infarktgröße und der mikrovaskulären Obstruktion konnte bestätigt und damit die Bedeutung der links-atrialen Funktion für den klinischen Outcome nach akutem Myokardinfarkt (AMI) gestützt werden. Zudem konnte der ε(s) als Prädiktor für das Auftreten eines schwerwiegenden kardialen Ereignisses, unabhängig von etablierten Risikofaktoren wie der LVEF, dem Alter, der Killip-Klasse und dem GLS, identifiziert werden.
Zusammenfassung:
Diese Arbeit demonstriert erstens die weiterhin unzureichende Inter-Hersteller-Reproduzierbarkeit der unterschiedlichen kommerziell verfügbaren CMR-FT-Softwarelösungen und betont damit die Notwendigkeit einer weiteren technischen Standardisierung sowie einer Etablierung softwareunabhängiger Cutoff-Werte.
Zweitens liefern unsere Ergebnisse einen nennenswerten Beitrag zum besseren Verständnis der Effekte unterschiedlicher Conditioning-Strategien und stärken die Bedeutung des MSI nach AMI als Marker für eine verbesserte kardiale Funktion. Drittens konnte mit dieser Arbeit der prognostische Mehrwert des CMR-FT nach AMI erstmals extern validiert werden.Aim:
To evaluate cardiac MRI-based myocardial feature tracking (CMR-FT) regarding its reproducibility, its feasibility for the assessment of cardioprotective effects of different conditioning strategies on myocardial function and its validation for an optimized risk stratification following ST-elevation myocardial infarction (STEMI).
Material and Methods:
CMR-cine images of 10 patients without significant reduction in left ventricular ejection fraction (LVEF) and 10 patients with a significantly impaired systolic function were analyzed using two different types of FT-software (TomTec, Germany; QStrain, Netherlands). Global left ventricular longitudinal circumferential and radial strains (GLS, GCS and GRS) were assessed. Differences in intra- and inter-observer variability within and between software types based on single and up to three repeated and subsequently averaged measurements were evaluated.
The effect of different conditioning strategies on myocardial function was assessed by analyzing left ventricular (GLS, GCS, GRS) and left atrial strain parameters (total strain (ε(s)), passive strain (ε(e)) and active strain (ε(a)) as well as left ventricular dyssynchrony parameters (the circumferential and radial uniformity ratio estimates CURE and RURE) in the different study groups of the Randomized-LIPSIA-conditioning study. Further, we investigated the effect of an increased myocardial salvage index (MSI) on left ventricular and left atrial function.
In the third part we aimed for the external validation of established cut-off values of the left ventricular strain (GLS, GCS, GRS), the left atrial strain (ε(s), ε(e), ε(a)) and the left ventricular dyssynchrony parameters (CURE and RURE) for the optimized risk stratification following STEMI by applying these values as well as assessing their prognostic merit over and above established cardiovascular risk factors in the Randomized-LIPSIA-conditioning cohort.
Results:
Inter-vendor agreement was highest for GCS followed by GLS. GRS showed the lowest inter-vendor agreement. Intra-vendor reproducibility was excellent for GCS and GLS, but lower for GRS. The impact of repeated measurements was most pronounced for GRS on an intra-vendor level. However, regardless of the number of repetitions, GRS was measured significantly higher with QStrain than with TomTec.
Despite the chosen conditioning regimen, there was no significant improvement in CMR-FT-based cardiac mechanics compared to conventional therapy using percutaneous coronary intervention alone. A positive effect of a combination therapy of remote ischemic conditioning and postconditioning could not be demonstrated. In contrast, we were able to show the MSI being significantly associated with a better cardiac function. A correlate of cardiac mechanics for a larger MSI could not be demonstrated.
The cut-off values for GLS, GCS, GRS, left atrial strain and the CURE, that were identified by Eitel, Schuster and Stiermaier et al. did also lead to an optimized risk stratification in the Randomized-LIPSIA-conditioning cohort. GLS and left atrial strain parameters even improved risk assessment in patients with preserved left ventricular ejection fraction (LVEF). The prognostic merit of the ε(s) for the prediction of mortality over and above LVEF, infarct size and microvascular obstruction could be validated, supporting the importance of a maintained left atrial function for clinical outcome following acute myocardial infarction (AMI). Moreover, the ε(s) was identified as an independent predictor of major adverse cardiac events independent of established risk factors as LVEF, age, Killip-class and GLS.
Conclusion:
First of all, this study demonstrates the still insufficient inter-vendor reproducibility of different, commercially available CMR-FT software solutions and thus stresses the necessity for further technical standardization between vendors and the establishment of vendor independent cut-off values.
Secondly, our results lead to the considerably improved understanding of the effects of different conditioning strategies and strengthens the importance of the MSI as a marker for an improved cardiac function after AMI. Thirdly, the prognostic merit of CMR-FT after acute myocardial infarction could be externally validated for the first time as the result of this work. 2021-09-1
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn 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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