1,720,954 research outputs found
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
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
Enantioselektive Totalsynthese von Morphinan-Alkaloiden aus alpha-Aminonitrilen
No full textZiel dieser Arbeit war die Entwicklung einer enantioselektiven Syntheseroute für pharmakologisch wirksame Morphinan-Alkaloide aus α-Aminonitrilen. Durch Alkylierung eines deprotonierten 1,2,3,4-Tetrahydroisochinolin-1-carbonitrils mit einem symmetrisch substituierten Benzylbromid-Bausteins und anschließender enantioselektiver Transferhydrierung nach Noyori, konnte das erste von fünf Stereozentren mit hoher optischer Reinheit aufgebaut werden. Die Synthese des Morphinan-Gerüstes gelang mittels Birch-Reduktion und Grewe-Cyclisierung. Letztlich wurde (–)-Dihydrocodein in einer Gesamtausbeute von 19.3% über 14 lineare Stufen mit einem Enantiomerenüberschuss von 95% erhalten. Daraus ergibt sich weiterhin eine formale Totalsynthese von (–)-Thebain nach literaturbekannten Methoden. Ein Zwischenprodukt der Syntheseroute dient außerdem als Ausgangsmaterial für eine formale Totalsynthese von (–)-Morphin und (–)-Codein.
Weiterhin war es möglich, alternativ durch eine elektrochemische intramolekulare Phenolkupplung eines 1-Benzyl-1,2,3,4-Tetrahydroisochinolins zum Morphinan-Gerüst zu gelangen. Hierfür wurde der Einfluss verschiedener N-Schutzgruppen auf den Verlauf der Reaktion untersucht.
Die dritte in dieser Arbeit untersuchte Synthesestrategie basiert auf einer intramolekularen Diels-Alder-Reaktion zum Aufbau des Morphinan-Gerüstes. Um zu überprüfen ob dieser geplante Schlüsselschritt überhaupt realisierbar ist, wurden erfolgreich zwei verschiedene α-Aminonitrile als Modellverbindungen synthetisiert. Verschiedene Experimente mit diesen Modellverbindungen führten allerdings leider nicht zum gewünschten Erfolg.
Das vierte in dieser Arbeit durchgeführte Teilprojekt ergab sich der Beobachtung, dass manche in dieser Arbeit synthetisierten Formamide über eine ungewöhnlich hohe Rotationsbarriere verfügen und sich chromatographisch, zumindest temporär, voneinander trennen ließen. Um diesem Phänomen auf den Grund zu gehen, wurden verschiedene kinetische Untersuchungen an einer ausgewählten Verbindung durchgeführt. Durch einfache kinetische Studien zur Interkonversion der E- und Z-Rotamere mittels HPLC konnte erfolgreich die Rotationsbarriere der Amidbindung ermittelt werden. Des Weiteren wurden dynamische HPLC Experimente durchgeführt, die einerseits die zuvor bestimmten Werte bestätigten und darüber hinaus zusätzliche Information über die enthalpischen und entropischen Beiträge lieferten. Abgerundet wurde die Studie durch DFT-Kalkulationen und den Vergleich der Ergebnisse der unterschiedlichen Methoden.The aim of this thesis was the development of an enantioselective synthetic route for pharmacologically active morphinan alkaloids from α-aminonitriles. By alkylation of a deprotonated 1,2,3,4-tetrahydroisoquinoline-1-carbonitrile with a symmetrically substituted benzyl bromide and subsequent enantioselective transfer hydrogenation with Noyori´s catalyst, the first of five stereocenters was synthesized with high optical purity. The construction of the morphinan skeleton was realized via Birch reduction and Grewe cyclization. Finally, (–)-dihydrocodeine was obtained in an overall yield of 19.3% over 14 linear steps with an enantiomeric excess of 95%. This compound can be converted to (−)-thebaine in high yield by known transformations, while (−)-codeine and (−)-morphine are available from an advanced intermediate.
Furthermore, the generation of the morphinan skeleton was achieved, alternatively, by an electrochemical intramolecular phenolic coupling of an 1-benzyl-1,2,3,4-tetrahydroisoquinoline. The influence of various N-protecting groups on the course of the reaction was studied.
The third synthetic strategy examined in this work is based on an intramolecular Diels-Alder reaction to construct the morphinan skeleton. Two different α-aminonitriles were successfully synthesized as model compounds to test the planned oxidative cycloaddition/cycloreversion key step. Several experiments using this model compounds, however, led not to the desired success.
The fourth subproject of the thesis resulted from the observation that some the synthesized formamides exhibit unusually high rotational barriers and could be temporarily separated from one another by chromatography (HPLC, TLC). The hindered rotation around the amide bond was investigated by dynamic high-performance liquid chromatography (DHPLC) and kinetic measurements of the interconversion of the rotamers. The experimental results of the different methods were compared to each other as well as to results obtained by DFT calculations
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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