1,720,986 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
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
Molecular analysis of the G20210A mutation in the 3' untranslated region of prothrombin
Get PDFDer G20210A-Polymorphismus im humanen Prothrombingen liegt in der 3'-UTR der mRNA und betrifft das letzte Nukleotid. Die Mutation führt bei Patienten zu einer erhöhten Plasma-Prothrombinkonzentration und zu einer verstärkten Thromboseneigung. Das Thromboserisiko ist für diese Patienten 1,3- bis 6,6-fach erhöht. Die Mutation beeinflusst aufgrund ihrer Lage nicht die Struktur des Proteins. Deshalb wurde postuliert, dass die erhöhte Prothrombinkonzentration bei betroffenen Patienten durch eine verlängerte Halbwertszeit der Prothrombin-mRNA, durch eine verbesserte Transkriptions-, Translations- oder Polyadenylierungseffizienz verursacht wird. Die Aufklärung des zugrunde liegenden Mechanismus ist Voraussetzung für die Entwicklung von therapeutischen Strategien.
Zur Untersuchung der Hypothese der mutationsbedingten höheren Stabilität der Prothrombin-mRNA wurden sowohl Wildtyp als auch 20210A 3'-Prothrombinbereich mit 97 bp 3'-UTR und 143 bp 3'-flankierende Region vor das 3'-Poly A-Signal eines beta-Globinreporterplasmids inseriert. Dieses Vektorsystem ermöglicht aufgrund der hohen Halbwertszeit der Globin-mRNA die Messung des Einflusses der 3'-Prothrombinregion auf die Stabilität der Reporter-mRNA. Die G20210A-Mutation an der Polyadenylierungsstelle des Prothrombingens führte in beta-Globinexpressionsstudien und bei rekombinanter Expression in verschiedenen Zelllinien nicht zu einer veränderten Halbwertszeit im Vergleich zur Wildtyp-mRNA. Sowohl die endogene Prothrombin-mRNA als auch beta-Globin-Prothrombin-Hybride wiesen eine hohe Halbwertszeit von 17 bis 50 h in primären Leberzellen und verschiedenen Zelllinien auf. Dabei war die Stabilität der mRNA abhängig von der Art der verwendeten Konstrukte und vom Differenzierungsstatus der Zellen.
Die Polyadenylierung erfolgte bei den beta-Globinkonstrukten nicht an der Poly A-Stelle der Prothrombin 3'-Region, sondern ausschließlich an der stromabwärts gelegenen Poly A-Stelle des Reporterplasmids. Nach Exzision der Vektor-Poly A-Stelle war eine unvollständige Prozessierung zu beobachten. Diese Daten weisen auf ein schwaches Polyadenylierungssignal oder auf fehlende cis-regulatorische Elemente in der 3'-Prothrombinregion hin. Die Verlängerung der 3'-flankierenden Prothrombinregion führte zur Reduzierung der Transkriptzahl auf zwei Transkripte, von denen das kleinere vermutlich die korrekt an Position 20210 polyadenylierte mRNA, das größere dagegen die Prä-mRNA oder ein inkorrekt prozessiertes Transkript repräsentierten. Demnach enthält die erweiterte 3'-flankierende Region zusätzliche regulatorische Elemente, die jedoch nicht zu einer 100 %igen Polyadenylierung führen.
Der Vergleich von Wildtyp- und 20210A-Transkriptmengen zeigte bei beta-Globinreportersystemen und bei rekombinanter mRNA einen erhöhten Anteil an polyadenylierter mRNA bei der Mutante. Diese Verschiebung zugunsten der korrekt prozessierten und damit für die anschließende Translation funktionellen mRNA führte bei Überexpression der mutierten Variante zu einer gegenüber dem Wildtyp 4-fach erhöhten Proteinkonzentration. Die Insertion der verlängerten 3'-Prothrombinregion in ein Luciferasereportersystem führte in Übereinstimmung mit den zuvor beschriebenen Befunden bei der Mutante zu einer erhöhten Luciferaseaktivität.
Alle Daten sprechen dafür, dass der erhöhte Prothrombinplasmaspiegel bei Patienten mit der G20210A-Transition im Prothrombingen durch eine verbesserte Polyadenylierungseffizienz der Prä-mRNA hervorgerufen wird. Der damit verbundene Anstieg der Prothrombin-mRNA-Menge könnte bei Patienten zu einer vermehrten Translation und Proteinbildung führen. Diese Befunde stimmen mit dem bei Mutationsträgern erhöhten Plasmagehalt an Prothrombin überein. Die weitere Untersuchung der beteiligten cis-regulatorischen Sequenzelemente und der daran bindenden Faktoren könnte zu einem besseren Verständnis von Mutationen in der 3'-untranslatierten Region weiterer Gene führen, die eine Erhöhung der mRNA-Menge zur Folge haben und als Grundlage für zukünftige Therapien dienen.The phenotype of the 20210A allele of the prothrombin gene is associated with elevated plasma levels of prothrombin and an increased risk of developing venous thrombosis. Since this mutation is located within the 3' untranslated region of the prothrombin gene, it has been postulated that the mutation might increase the stability of the prothrombin mRNA, the efficiency of transcription or translation or the efficiency of polyadenylation.
The half-life of the endogenous prothrombin mRNA was 50 h, measured in rat liver cells and in the human hepatocellular carcinoma cell line HepG2.
To study the hypothesis whether the G to A transition at position 20210 of the prothrombin gene affects a regulatory sequence involved in turnover of prothrombin mRNA, the half-life of chimeric globin mRNA containing the 3' untranslated and 143 bp 3' flanking region of prothrombin wild-type or prothrombin mutant was compared. In stably transfected HepG2 and COS-1 cells there was no significant difference in mRNA half-life obtained from the wild-type or mutant prothrombin mRNA. The stability of the chimeric mRNA was dependent on the differentiation of the cells and varied between 17 h and over 50 h.
The 3' end cleavage and polyadenylation of the chimeric mRNA didn t occur at the upstream poly (A) site of prothrombin but at the downstream poly (A) site of the reporter plasmid. Excision of the vector poly (A) site resulted in decreased 3' end cleavage efficiency and incorrectly processed mRNAs. This data suggest a weak poly (A) signal of prothrombin or the absence of cis-regulatory elements in the constructs. The extension of the prothrombin 3' flanking region resulted in a reduction of the incorrect processed transcripts, indicating the involvement of downstream cis-acting elements in 3' end cleavage and polyadenylation efficiency. The smaller transcript represented the correct 3' end processed mRNA, whereas the second transcript seemed to be 3' extended and probably arose from read-through at the prothrombin poly (A) site.
The comparison of wild-type and G20210A transcript levels indicates increased amounts of correct polyadenylated mutant mRNA. This upregulation of 3' end processing efficiency and greater abundance of functional mRNA caused by the prothrombin G->
A transition led to a 4-fold increase in recombinant protein concentration in stably transfected COS-1 cells.
The insertion of the mutant 3' untranslated region and prolonged 3' flanking region of prothrombin additionally contributes to higher luciferase activity levels, probably due to increased polyadenylation efficiency.
In conclusion, the elevated plasma prothrombin level in carriers of the prothrombin 20210A allele is probably a result of the improved 3' end cleavage and polyadenylation efficiency and not the result of an increased stability of the prothrombin mRNA
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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