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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
Tool for Disrupting and Monitoring Sialic Acid Biosynthesis
Get PDFSialinsäuren sind Teil der äußersten Komponente der Glykokalyx aller Wirbeltiere. Als solche sind sie grundlegende Marker in physiologischen und pathologischen Prozessen. Der „Hauptregulator“ der Sialinsäure-Biosynthese ist die bifunktionelle UDP-N-Acetylglucosamin-2-Epimerase/N-Acetylmannosamin-Kinase (GNE/MNK). Das Hauptziel dieser Dissertation war die Identifizierung neuer Inhibitoren der GNE-Subdomäne, die zur Hemmung der Sialinsäurebiosynthese in Zellen und zur Verringerung der Sialylierung der Zelloberfläche eingesetzt werden könnten. Zu diesem Zweck wurde GNE rekombinant exprimiert und eine Screening-Kampagne mit fast 70 000 Verbindungen gegen seine Aktivität durchgeführt. Die primären Treffer aus der Screening-Kampagne wurden anschließend in vitro und in cellulo charakterisiert. Die Inhibitoren haben nicht auf Zellen funktioniert, dafür haben sie in einem neu entwickelten NMR basierten Assay GNE Aktivität im Rattenleberzytosolextrakt inhibiert.Sialic acids are part of the outermost component of the glycocalyx of all vertebrates. As such, they are fundamental markers in physiological and pathological processes. The "main regulator" of sialic acid biosynthesis is the bifunctional UDP-N-Acetylglucosamine-2-Epimerase/N-Acetylmannosamin Kinase (GNE/MNK). The main objective of this dissertation was the identification of new inhibitors of the GNE subdomain, which could be used to inhibit sialic acid biosynthesis in cells and reduce the sialylation of the cell surface. For this purpose, GNE was recombinantly expressed and a screening campaign against its activity was conducted with nearly 70,000 compounds. The primary hits from the screening campaign were subsequently characterized in vitro and in cellulo. The inhibitors did not work on cells, but they inhibited GNE activity in a rat liver cytosol extract in a newly developed NMR-based assay
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
Reinigung und Charakterisierung von alpha-1,3-Gal spezifischen Antikörpern
No full textDas α-Gal Epitop ist ein immunogenes Glykan-Epitop, das aus der Trisaccharidstruktur GlcNAc-β-1,4-Gal-α-1,3-Gal besteht. Es kann als Anteil komplexer N-Glykane auf Glykoproteinen oder als Lipid-verknüpftes Glykokonjugat auf Zelloberflächen von Nicht Primaten wie Neuweltaffen, Schweinen und Kaninchen präsentiert werden. Menschen und Altweltaffen exprimieren das α-Gal Epitop aufgrund der evolutionär bedingten Inaktivierung der α-1,3-Galaktosyltransferase nicht. Antikörper gegen das α-Gal Epitop werden als Immunantwort gegen Darmbakterien produziert, die α-Gal Strukturen auf ihrer Lipopolysaccharidschicht tragen. Es ist bekannt, dass α-Gal tragende Proteine zu Abstoßungsreaktionen und Anaphylaxie in Primaten führen. Obwohl viele geschichtliche Fakten und Eigenschaften des α-Gal Epitops bekannt sind, existiert nur wenig Wissen betrefflich der Charakteristiken von anti-Gal Antikörpern im Menschen. Darum wurden anti Gal Antikörper in dieser Arbeit erstmalig aus Octagam gereinigt und hinsichtlich ihrer Spezifität gegenüber dem α Gal Epitop, der Verteilung von IgG Subklassen, ihrem isoelektrischen Punkt und ihrer N Glykosylierung untersucht. Die bislang nur mit wenigen Methoden gezeigte Spezifität von anti-Gal Antikörpern zum α Gal Epitop wurde in meiner Arbeit durch verschiedene orthogonale Methoden, darunter ELISA, Erythrozytenagglutination, Oberflächenplasmonresonanz und Western Blot, in bisher nicht vorhanden gewesener Detailliertheit und Tiefe nachgewiesen. Neben dem erfolgreichen Nachweis der Antikörperspezifität wurden erstmalig bedeutende anti-Gal Charakteristika wie die Distribution von IgG Subklassen, das isoelektrische Verhalten und die N Glykosylierung analysiert. Gereinigte und spezifische anti-Gal Antikörper bestanden hauptsächlich aus dem IgG2 Isotyp (83%). Anti Gal Antikörper zeigten human-IgG ähnliches Verhalten sowie eine human-IgG ähnliche Glykosylierung, dominiert von biantennären und fukosylierten N Glykanstrukturen. Die Verwendung der gereinigten Antikörper als Werkzeug für die Detektion von α-Gal Strukturen auf Cetuximab, bovinem Thyroglobulinen und rekombinantem Faktor VIII wurde innerhalb dieser Arbeit untersucht und das gewonnene Wissen über verschiedene Charakteristika der anti-Gal Antikörper wurde in einen Zusammenhang mit im humanen Organismus ablaufenden Immunreaktionen gestellt. Die Experimente und Versuche dieser Arbeit gaben einen zuvor noch nicht existenten Einblick in Eigenschaften und Charakteristika isolierter anti Gal Antikörper und zeigten mögliche Verwendungen gereiniger anti-Gal Antikörper zur Detektion des α-Gal Epitops auf.The α-Gal epitope is an immunogenic glycan epitope which consists of the trisaccharide structure GlcNAc-β-1,4-Gal-α-1,3-Gal. It can be presented as part of complex type N-glycans on glycoproteins or as lipid-linked glycan conjugate on cell surfaces of non-primate mammalians like new world monkeys, pigs and rabbits. Humans and old world monkeys do not express the α-Gal epitope due to the evolutionary inactivation of the α-1,3-galactosyltransferase which is the catalyzing enzyme for its synthesis. Antibodies against the α-Gal epitope are produced naturally as immunological response to intestinal bacteria that bear α-Gal structures on their lipopolysaccharide chains. It is common knowledge that α-Gal bearing proteins lead to hyperacute rejection and anaphylaxis in primate organisms. Although much about α-Gal and its background is already known, only little knowledge exists concerning the characteristics of anti-Gal antibodies in human.
Therefore, for the first time, anti-Gal antibodies were purified from Octagam and characterized in terms of specificity towards the α-Gal epitope, IgG subclass distribution, isoelectric behaviour and glycosylation. The specificity of anti-Gal antibodies to the α Gal epitope, which so far has been shown only with a few methods, has been investigated in my work by various orthogonal methods including ELISA, erythrocyte agglutination, SPR and Western Blot. In addition to the successful detection of antibody specificity, significant anti-Gal characteristics such as distribution of IgG subclasses, isoelectric behavior, and N glycosylation were analyzed for the first time.
Purified anti-Gal antibodies consisted mainly of the IgG2 isotype (83%). Anti-Gal showed human IgG like isoelectric behaviour as well as a typical human IgG-like N-glycosylation profile dominated by biantennary, fucosylated N-glycan structures. The usage of these purified antibodies as a tool for the detection of α-Gal structures on Cetuximab, bovine Thyroglobuline and recombinant Factor VIII is investigated and discussed within this work. The gained knowledge about the characteristics of the anti-Gal antibody was linked to immune reactions occurring in the human body for the first time. The experiments and investigations carried out in this work gave a previously non-existent insight into the properties and characteristics of isolated anti-Gal antibodies and discovered the suitability of the purified anti Gal antibody as detection antibody for the α-Gal epitope
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
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