1,720,962 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Mehrstufensynthesen unter Einsatz von Oxidoreduktasen
Get PDFThe focus of my Ph.D.-thesis was on the combination of biocatalytic and chemocatalytic processes towards the development of one-pot multi-step processes in aqueous reaction media. Such multi-step processes are still rare and at the same challenging and interesting from the perspective of sustainable chemistry. This research consists of the following parts: - Combination of metal and biocatalysis - Combination of organo- and biocatalysis - Combination of enzymatic oxidation reaction steps Combination of metal and biocatalysis In my PhD-thesis the first example of a one-pot process in which a palladium-catalyzed cross-coupling reaction is combined with a biotransformation in an aqueous reaction medium has been described. This one-pot process was applied for the synthesis of chiral biaryl alcohols through Suzuki cross-coupling and subsequent asymmetric enzymatic reduction. The resulting reaction mixture from the Suzuki cross coupling turned out to be compatible with a subsequent alcohol dehydrogenase (ADH)-catalyzed reaction. When this Suzuki cross-coupling was followed by an enzymatic reduction (after adjustment of the pH value to pH 7) under substrate-coupled cofactor regeneration with 2 propanol, the desired products were formed with high conversion and excellent enantioselectivity of >99% ee. An additional challenge is the synthesis of enantiomerically pure alcohols via combination of Sonogashira-cross-coupling reaction and biotransformation. In the study of the one-pot two-step process two methods were found. In method one at an initial step a Sonogoshira-cross-coupling is carried out followed - after pH adjustment to pH 7 – by an enzymatic reduction. Another possibility is the change of the reaction sequence. In contrast to the first method, the ketone will be reduced enzymatically at first and then the Sonogashira-cross-coupling reaction follows. Both methods enabled an access to the desired alcohols, which were obtained with excellent enantiomerically purity (>99% ee). Combination of organo- and biocatalysis The combination of asymmetric organo- and biocatalytic reaction sequences is a further interesting option. In such a concept, the reaction mixtures resulting from the organocatalytic reaction route shall be compatible with a direct subsequent enzymatic reduction without the need for a work-up of the intermediate. In this connection, in my work the biocompatibility of a chiral organocatalyst with an alcohol dehydrogenase has been successfully demonstrated by means of spectrophometric study. Another possibility is the combination of the Morita-Baylis-Hillman-reaction and the biocatalytic reduction of activated C=C double bonds. Such type of biotransformation represents an enzymatic reaction with high application potential in organic synthesis. Successful preliminary biotransformations with enzymatic in situ cofactor recycling confirmed the synthetic potential of steroid reductases for small molecules with an activated C=C-double bond. Furthermore, this study represents one of the rare examples demonstrating the capability of steroid reductases to accept small monocyclic and acyclic molecules bearing a C=C double bond in conjugation to an electron-withdrawing group as substrates. Thus, it appears that steroid reductases, in particular progesterone reductases of plant origin, possess a broader substrate spectrum than widely expected. Combination of enzymatic oxidation reaction A combination of two oxidoreductases in the biocatalytic oxidation process starting from cycloalkanes has been developed for the synthesis of cyclic ketones from cycloalkanes. This reaction concept represents a simple process for the synthesis of the important industrial compounds. The one-pot process is based on the combination of a P450-monooxygenase and an alcohol dehydrogenase in the presence of NADPH as co-enzyme. The in situ cofactor regeneration is possible without additional other substrates or enzyme additives. As a “proof of concept” a one-pot two-step synthesis was successful done for the synthesis of cyclooctanone and cyclodecanone. Advantages of this synthetic concept are the aqueous reaction medium, room temperature and air / molecular oxygen as oxidation agent.Ziel dieser Arbeit war es, neue, effiziente Syntheserouten zu entwickeln, die die Kombination von chemo-enzymatischen oder bi-enzymatischen Reaktionsschritten bieten. Zu diesem Zweck sollte der Einfluss von Metall- und Organokatalyse auf die Enzymaktivität untersucht werden und optimale Verfahrensmöglichkeit vorgeschlagen werden. Dies wird in drei folgenden Abschnitten der Arbeit aufgeteilt: - Palladium-Katalyse in Kombination mit Biotransformation - Organokatalytische C-C-Bindungsbildungen in Kombination mit Biotransformation - Kombination von enzymatischen Oxidationsreaktionen Palladium-Katalyse in Kombination mit Biotransformation Es wurde ein neuer innovativer Syntheseweg zur Herstellung von chiralen aromatischen Alkoholen und Dialkoholen etabliert. Die vorgestellte Methode basiert auf einer Metall-katalysierten Kreuzkupplung und einer Biotransformation in einer sequenziellen Reaktion. Solche Eintopfverfahren zeigten, dass Metall- und Biokatalyse zu einer Eintopfsynthese kombiniert werden können. Die hergestellten chiralen Produkte sind enantiomerenrein, die Enantioselektivität wird durch die Wahl des Enzyms ((S)- oder (R)-ADH) bestimmt. Als Erweiterung dieses Verfahrens wurde die Kombination von Sonogashira-Reaktion und Biotransformation untersucht. Die Durchführung der Eintopfsynthese erfolgt in zwei möglichen Reaktionssequenzen. In der ersten Sequenz findet zunächst die Sonogashira-Reaktion statt, gefolgt von der enzymatichen Reduktion (Methode 1). Die Durchführung der zweiten Eintopfreaktion (Methode 2) erfolgt in umgekehrter Reihenfolge der Teilschritte. Organo-katalytische C-C-Bindungsknüpfungen in Kombination mit Biotransformation Es wurde die Synthese von einem aliphatischen 1,3-Diol unter Kombination einer Aldol-Reaktion und einer Biotransformation untersucht. Das Aldol-Reaktionsprodukt konnte jedoch nicht enzymatisch reduziert werden. Der Einfluss der Organokatalysatoren auf die Aktivität der Enzyme wurde ebenfalls untersucht. Dabei konnte ein erfolgreich geringer Verlust der Aktivität der Enzyme in Anwesenheit der Organokatalysatoren feststellen werden. Als weiteres Beispiel der Kombination von Organo-katalytischer C-C-Bindungsbildung und Biotransformation wurde eine Syntheseroute zum Roche-Ester entwickelt. Diese Methode basiert auf einer DABCO-katalytischen Morita-Baylis-Hillman-Reaktion und anschließender Reduktion des β Hydroxyacrylsäureethylesters mittels einer Enoat-Reduktase. Die in dieser Arbeit durchgeführten Untersuchungen zeigten, dass insbesondere die Enzyme At5β-StR aus A. thaliana und GOx-8 aus G. oxydans als Biokatalysatoren für die Reduktion eine Reihe von Enonen sowie der Vorstufe für den Roche-Ester geeignet sind. Kombination von enzymatischen Oxidationsreaktionen Das Ziel dieses Abschnittes der Arbeit lag in der Entwicklung eines hocheffizienten und breit anwendbaren Oxidationsverfahrens unter Einsatz von Oxidoreduktasen. Diese neue Methode bietet eine Synthese von industriell wichtigen Produkten (cyclischen Ketonen) in einer Eintopfsynthese bei milden Reaktionsbedingungen ohne Verwendung problematischer Oxidationsmittel. Das Verfahren besteht aus zwei Schritten. Der erste ist eine Monooxygenase-katalysierte Hydroxylierungsreaktion, der zweite beinhaltet die ADH-katalysierte Oxidation des Alkohols zum entsprechenden Keton. Dieses Verfahren wurde erfolgreich für die Synthese von Cyclooctanon und Cyclodecanon angewendet
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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