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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
Anaerobe Atmungsprozesse in Bakterien der Klasse Dehalococcoidia
No full textThe bacterial class Dehalococcoidia, phylum Chloroflexi, encompasses several cultivated strains and many so far uncultivated bacteria, known from molecular detection of their 16S rRNA gene sequences in marine sediments. All cultivated representatives exclusively respire with halogenated compounds as terminal electron acceptor in a process termed organohalide respiration. However, it is not known whether organohalide respiration can explain the abundance and ubiquitous distribution of Dehalococcoidia in marine pristine sediments. In the current work, electron acceptors for respiration of Dehalococcoidia were investigated with the model organism Dehalococcoides mccartyi strain CBDB1 to gain insight into which properties of halogenated compounds are required to serve as electron acceptor of Dehalococcoidia and might in part explain their abundance at marine sites. For this, a microtiter plate-based assay was established to measure reductive dehalogenase activity – the key enzyme in organohalide respiration. D. mccartyi strain CBDB1 dehalogenated chlorinated benzonitriles, chlorinated anilines and brominated phenols, benzenes, pyridines, furoic and benzoic acids and specific activities of 4.5 to 241 nkat mg^-1 protein were determined. In cultivation experiments, growth yields of 0.1 x 10^14 to 2.3 x 10^14 cells mol^-1 halogen released were obtained with strain CBDB1. Brominated electron acceptors were generally dehalogenated to a further extent than their chlorinated equivalents and showed higher specific activity rates in resting cell assays. Results of shotgun proteomics and activity assays suggest that the same reductive dehalogenases are involved in the dehalogenation of brominated and chlorinated benzenes, indicating chemical properties influence reductive dehalogenation patterns of strain CBDB1. The correlation of density functional theory calculations with microbial and biochemical experiments revealed that functional groups decreasing electron density at the halogen and not at the halogen-substituted carbon enhance reductive dehalogenation. The most positive halogen partial charge predicted the regioselective dehalogenation catalysed by strain CBDB1 for up to 96% of all evaluated molecules. These findings suggest a cobalamin–halogen interaction during reductive dehalogenation which stands in contrast to previous models of reductive dehalogenation. A halogen– cobalamin interaction could in part explain the broad electron acceptor diversity of organohaliderespiring Dehalococcoidia suggesting that a multitude of natural organohalogens – including brominated aromatics – could serve as natural halogenated electron acceptor for respiration and growth of Dehalococcoidia in marine sediments. In addition, the established prediction systems may allow for improved fate prediction of halogenated compounds from anthropogenic or natural sources in the environment. Reductive dehalogenation of brominated aromatics was also shown to occur in marine deep-sea sediment microcosms with activity assays, inhibition studies and cultivation experiments although no Dehalococcoidia were detected. However, the conducted experiments demonstrated that similar dehalogenation patterns observed with model organism strain CBDB1 occur in non-contaminated deep-sea sediments. To investigate the potential of Dehalococcoidia to respire non-halogenated electron acceptors, the genetic information from the single amplified Dehalococcoidia genome SAG-C11 was used to design primers for a newly identified class of dissimilatory sulphite reduction genes (dsr) in Chloroflexi. The primers were used to study sediment samples from different locations and depths for the presence of Chloroflexi-related dsr genes. Several dsr genes located in a similar genetic context as observed in SAG-C11 and affiliating with dsr genes from SAG-C11 in phylogenetic analyses were detected in sediments from Aarhus, the Baffin Bay and in tidal flat sediments of the Wadden Sea. The obtained dsrAB genes shared 71–100% nucleotide sequence identities with dsrAB of SAG-C11 suggesting that dissimilatory sulphite reduction is a more widespread mode of respiration in the class Dehalococcoidia and could contribute together with organohalide respiration of brominated natural electron acceptors to the abundance and ubiquitous presence of Dehalococcoidia in marine sediments.Die vorliegende Arbeit beschreibt Formen der anaeroben Atmung der bakteriellen Klasse Dehalococcoidia, Abteilung Chloroflexi, welche zu den häufigsten und abundantesten Bakteriengruppen mariner Sedimente gehört und deren kultivierten Vertreter aus terrestrischen Habitaten ausnahmslos auf eine Atmung mit halogenierten organischen Verbindungen (Organohalidatmung) angewiesen sind. Kultivierung und Mikrotiterplatten-basierte Aktivitätstests mit strukturell unterschiedlichen Elektronenakzeptoren zeigten, dass Dehalococcoidia Modellorganismus Stamm CBDB1 chlorierte Benzonitrile, chlorierte Aniline und bromierte Phenole, Benzole, Pyridine, Furonund Benzoesäuren dehalogenierte. Wachstumsausbeuten von 0,1 x 10^14 bis 2,3 x 10^14 Zellen pro Mol freigesetztem Halogen Anion und spezifische Aktivitäten von 4,5 bis 241 nkat pro mg Protein wurden gemessen. Bromierte Aromaten wurden weitergehend und mit höheren spezifischen Aktivitäten dehalogeniert als ihre chlorierten Äquivalente. Aktivitätstests und Shot-Gun Proteomik deuteten darauf hin, dass die gleichen reduktiven Dehalogenasen in die Umsetzung der getesteten bromierten und chlorierten Benzole involviert sind. Bromierte aromatische Verbindungen, die in marine Habitaten vorkommen, könnten somit als natürliche Elektronenakzeptoren für Organohalid-atmende Dehalococcoidia in marinen Sedimenten dienen. Eine reduktive Dehalogenierung bromierter Verbindungen wurde auch in Aktivitätstests mit Zellen aus marinen Sediment-Mikrokosmen und durch Inhibitionsstudien nachgewiesen. Obwohl keine Chloroflexi in den marinen Sediment- Mikrokosmen detektiert werden konnten, zeigten die Experimente, dass reduktive Dehalogenierung auch in marinen nicht-kontaminierten Tiefseesedimenten vorkommen kann. Die Korrelation mikrobiologischer und biochemischer Versuche mit Dichtefunktionaltheorie-basierten Berechnungen verschiedener Partialladungs-Modelle zeigte, dass die regioselektive Dehalogenierung durch Stamm CBDB1 mit Hilfe der positivsten Halogen-Partialladung für 96% der untersuchten Moleküle vorausgesagt werden konnte. Außerdem konnte gezeigt werden, dass funktionelle Gruppen, die die Elektronendichte am Halogenatom verringern, die reduktive Dehalogenierung unterstützen. Dies weist auf eine Cobalamin–Halogen Interaktion während der reduktiven Dehalogenierung hin und steht im Gegensatz zu bisherigen Modellen der reduktiven Dehalogenierung. Eine Cobalamin–Halogen Interaktion könnte dazu beitragen, das breite Elektronenakzeptoren Spektrum Organohalid-atmender Dehalococcoidia zu erklären und könnte Organohalid-atmenden Dehalococcoidia in marinen Sedimenten erlauben, verschiedenste halogenierte Verbindungen wie z.B. bromierte komplexe Aromaten für die Atmung zu nutzen. In einem weiteren Teil dieser Dissertation wurde mit molekularbiologischen Methoden das Potential von Dehalococcoidia untersucht, nicht-halogenierte Elektronenakzeptoren zu nutzen. Dies könnte die Stratifikation von Dehalococcoidia Subgruppen entlang geochemischer Gradienten erklären. Dazu wurden mit Hilfe der Genominformation einer Dehalococcoidia-Einzelzelle („SAG-C11“) PCR-Primer entwickelt, die spezifisch dsr Gene in Dehalococcoidia amplifizierten. Mit diesen Primern wurden das Vorkommen und die Diversität der dissimilatorischen Sulfitreduktase (dsr) in Dehalococcoidia in Sedimenten verschiedener Orte und Tiefen untersucht. Unterschiedliche dsr Gene, die sich in einem ähnlichen genetischen Kontext wie in SAG-C11 befanden und in phylogenetischen Analysen mit dsr Sequenzen aus SAG-C11 gruppierten, wurden in Sedimenten der Aarhusbucht, der Baffinbucht und in Wattsedimenten der Nordsee nachgewiesen. Nukleotidsequenzähnlichkeiten von 71–100% der aus marinen Sedimenten amplifizierten dsrAB-Sequenzen zu den dsrAB-Sequenzen aus SAG-C11 weisen darauf hin, dass dissimilatorische Sulfitreduktion ein verbreiteter Atmungsprozess in Dehalococcoidia ist und zusammen mit der Organohalidatmung bromierter Verbindungen zu einer Erklärung der ubiquitären Verbreitung von Dehalococcoidia in marine Sedimenten in unterschiedlichen biogeochemischen Zonen beitragen kann.EC/FP7/202903/EU/Microbiology of Dehalococcoides-like Chloroflexi/MICROFLE
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
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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