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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
Identifizierung von REVOLUTA Zielgenen zeigt eine Verbindung zwischen Blattmusterbildung und schatteninduzierten Wachstumsprozessen auf
No full textPlants are sessile organisms and thus have to cope with unfavorable growth
conditions. To survive in an ever-changing environment, they have to constantly
align their growth behavior to biotic and abiotic factors.
In their struggle for water, nutrients and light in a highly competitive environment, plants have evolved gene- and hormone-regulatory networks enabling them to counteract suboptimal conditions by inducing elongation growth. In this thesis I show that the interplay of homeodomain-leucine zipper (HD-ZIP) transcription factors and plant hormones act as an adjusting screw between the inherent growth programs and the outer world.
REVOLUTA, a class III homeodomain-leucine-zipper (HD-ZIPIII) transcription
factor, plays a crucial role in many polarity-associated patterning processes.
Using a ChIP-Seq (Chromatin-Immuno-Precipitation-Sequencing) approach we
were able to identify a number of direct REVOLUTA target genes. Some of these
targets are involved in controlling developmental processes, while a significant
number is involved in responding to abiotic stimuli.
Two of the identified target genes are: TRYPTOPHAN AMINOTRANSFERASE OF
ARABIDOPSIS1 (TAA1) und YUCCA5 (YUC5), whose gene products are involved
in biosynthesis of auxin. Additionally, several class II homeodomain-leucine-zipper (HD-ZIPII) transcription factors were identified as direct REV targets. These HDZIPII factors are known to regulate shade-associated growth processes. We were able to show that HD-ZIPIII factors regulate HD-ZIPII factors, which is a prerequisite for a full shade-avoidance response. In addition, we were able to
establish a new link between HD-ZIPII factors and leaf patterning.
KANADI1 (KAN1), a transcriptional repressor of the GARP family, acts
antagonistically to REVOLUTA during leaf patterning. We could show that REV
and KAN1 antagonistically regulate several shared target genes. Furthermore, we
revealed that REV and KAN1 also control shade growth in an antagonistic
manner.
Finally, we identified a new positive feedback-loop regulating REV mRNA stability.
It is known, that the ARGONAUTE10 (AGO10) protein sequesters microRNAs of
the miR165/166 family that regulate HD-ZIPIII transcript stability. We were able to show, that AGO10 expression is directly and positively controlled by REV, thereby REV established a direct and positive feedback loop.
In summary, this thesis added to the expansion of the regulatory network around
REVOLUTA. In addition to the identification of a new positive feedback-loop we
were able to ascribe new functions for the REV/KAN1 module in shade-induced
growth promotion. Finally, we discovered that class II homeodomain-leucinezipper
proteins have a crucial role in leaf patterning.Pflanzen führen eine standortgebundene Lebensweise. Aus diesem Grund
müssen sie sich permanent an wechselnde biotische und abiotische Bedingungen
anpassen. Dies geschieht durch das Zusammenspiel inhärenter genetisch
determinierter Programme mit Signalwegen, die auf äußere Stimuli reagieren.
Um im Kampf um Wasser, Nährstoffe und Licht in einer stark von Konkurrenz
geprägten Umwelt zu überleben, haben Pflanzen komplexe regulatorische
Netzwerke etabliert, bei welchem Transkriptionsfaktoren und Hormone eine
entscheidende Rolle spielen. Im Rahmen dieser Dissertation zeige ich auf, dass
das Zusammenspiel von Homeodomänen-Leuzin-Zipper-Transkriptionsfaktoren
und Pflanzenhormonen eine „Stellschraube“ zwischen dem inhärenten
Entwicklungsprogrammen und der Antwort auf äußere Reize darstellt.
REVOLUTA, ein Klasse III Homeodomänen-Leuzin-Zipper Transkriptionsfaktor
(HD-ZIPIII), spielt in vielen polaritäts-assoziierten Musterbildungsprozessen eine entscheidende Rolle.
Mittels der Hochdurchsatz-Sequenzierungsmethode ChIP-Seq (Chromatin-
Immunopräzipitationssequenzierung) wurden zahlreiche direkte REVOLUTAZielgene
identifiziert, welche einerseits in Entwicklungsprozesse andererseits in
die Reaktion auf abiotische Faktoren involviert sind.
Zwei dieser Zielgene sind TRYPTOPHAN AMINOTRANSFERASE OF
ARABIDOPSIS1 (TAA1) und YUCCA5 (YUC5), welche unter Regulation von
REVOLUTA das Wachstumshormon Auxin synthetisieren. Des Weiteren wurden
Klasse II Homeodomänen-Leuzin-Zipper Transkriptionsfaktoren als Zielgene von
REVOLUTA identifiziert, welche unter dessen Kontrolle nicht nur wie bisher
bekannt für schatteninduzierte Hypokotylverlängerung verantwortlich sind,
sondern auch in der von REVOLUTA gesteuerte Blattmusterbildung eine
entscheidende Rolle spielen.
Als Gegenspieler von REVOLUTA in der Blattmusterbildung agiert KANADI1
(KAN1), ein transkriptioneller Repressor aus der GARP-Familie. Es konnte gezeigt
werden, dass durch die gemeinsame Regulation von Zielgenen in der
Auxinsynthese und der Schattenantwort, sowohl REVOLUTA als auch KANADI1
in beiden Prozessen eine gegensätzliche Rolle spielen.
Zusätzlich konnte anhand der ChIP-Seq-Daten eine neue positive Feedback-
Schleife für REVOLUTA identifiziert und eine bereits bekannte genauer
charakterisiert werden. In beiden Fällen führt eine genetische Veränderung zu
Veränderungen in der Blattmusterbildung. REVOLUTA wird posttranskriptionell
von den microRNA Familien miR165 und miR166 reguliert. Ich konnte zeigen,
dass ARGONAUTE10, welches die miRNA165/166 bindet und in ihrer Wirkung
inhibiert, durch REVOLUTA direkt positiv transkriptionell reguliert wird. Des
Weiteren konnte gezeigt werden, dass REVOLUTA die Genexpression von
LITTLE ZIPPER Mikroproteinen direkt reguliert, welche in einer negativen
Feedback-Schleife REVOLUTA posttranslational inhibieren.
Zusammengefasst lässt sich sagen, dass im Rahmen dieser Dissertation das
regulatorische Netzwerk um REVOLUTA signifikant erweitert wurde. Es konnten
nicht nur neue Feedback-Schleifen identifiziert und genauer charakterisiert
werden, sondern es wurde eine Funktion für REVOLUTA und KANADI1 in der
Auxin-vermittelten Schattenvermeidungsantwort aufgeklärt. Darüber hinaus konnte
gezeigt werden, dass die an der Schattensignaltransduktion beteiligten Klasse II
Homeodomänen-Leuzin-Zipper Transkriptionsfaktoren auch eine wichtige Rolle in
der Blattmusterbildung spielen
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
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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