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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
Resistencia a antimicrobianos y virulencia en cepas no-clínicas de pseudomonas aeruginosa
No full textPseudomonas aeruginosa es un patógeno oportunista, con una gran versatilidad metabólica y extraordinaria habilidad para crecer en distintos nichos ecológicos. P. aeruginosa es uno de los mayores responsables de infecciones nosocomiales, caracterizado por su resistencia a antibióticos y su gran arsenal de factores de virulencia. Existen múltiples estudios evaluando la relación resistencia a antibióticos-virulencia en cepas clínicas; mientras que los trabajos realizados con Pseudomonas de muestras no-clínicas son nulos o incompletos.
Por ello, los dos primeros objetivos de esta tesis fueron estudiar la prevalencia de Pseudomonas en muestras fecales de animales sanos y de niños y en alimentos vegetales; así como determinar su fenotipo de resistencia a agentes antipseudomónicos. La prevalencia de Pseudomonas en animales y en niños fue de 6,5 y 6,7%, respectivamente; mientras que en alimentos vegetales fue de 53,1%. De los 330 aislados obtenidos, P. putida y P. aeruginosa predominaron entre las 20 especies detectadas. El 44,8% de los aislados de Pseudomonas spp. mostró resistencia al menos a uno de los antibióticos testados, destacando aztreonam (41,5%). El fenotipo de multirresistencia se detectó en cuatro aislados (1,2%). P. aeruginosa se aisló en 6,3% de las muestras de niños, en 0,8% de animales y en 17,9% de alimentos vegetales; caracterizadas por su alto porcentaje de sensibilidad antimicrobiana (93,1%).
El tercer objetivo fue tipificar molecularmente los aislados de Pseudomonas spp., observándose una alta diversidad clonal mediante PFGE. No se detectaron patrones relacionados entre cepas de distintos orígenes. En las 76 cepas de P. aeruginosa, el serotipo O:6 fue el más frecuente (38%) y también se observó una elevada diversidad clonal (70 patrones de PFGE). Entre las 55 secuencias tipo (ST) detectadas por MLST, 14 de ellas fueron nuevas, y algunos clones (como ST244, ST252, ST253, ST277, ST395 y ST1033) se repitieron entre las cepas aisladas de niños y de alimentos vegetales. Destaca la presencia de clones intercontinentales, como ST155, ST244, ST252, ST274 y ST395, entre las cepas de P. aeruginosa de los distintos orígenes.
El estudio de los mecanismos de resistencia a carbapenémicos también fue un objetivo. Ningún aislado presentó un fenotipo carbapenemasa; sin embargo, las cepas de P. aeruginosa mostraron un gran polimorfismo en la proteína OprD (13 patrones). Se detectó la secuencia de inserción ISPa1635 truncando el gen oprD (GenBank MH050332) en una de las cepas resistentes a imipenem.
El quinto objetivo fue estudiar la presencia de factores de virulencia, la producción de biofilm, pigmentos, y la actividad elastasa en cepas de P. aeruginosa. El 80,2% de P. aeruginosa presentó el genotipo exoU-/exoS+; mientras que el genotipo exoU+/exoS-, asociado a una elevada citotoxicidad, se detectó en el 17,1%. Seis P. aeruginosa aisladas de animales sanos carecían de los genes codificantes de los efectores del Sistema de Secreción Tipo 3 y de los genes exoA y rhlC, pero ninguna de estas seis cepas amplificó el gen de la exolisina ExlA, descrito recientemente. Todas las cepas de P. aeruginosa portaban los genes lasA, lasB, aprA, rhlAB, rhlI y rhlR. Los genes lasI y lasR no amplificaron en tres cepas que pertenecían al clon ST155. Se detectaron secuencias de inserción (ISPre2, IS1411, ISPa91 y IS1394) truncando el gen lasR (GenBank MH050329, MH050330, MH050331, MG815635, respectivamente) en cuatro cepas de P. aeruginosa. La producción de biofilm, piocianina y piorrubina, así como la actividad elastasa fue superior a la cepa de referencia PAO1 en el 92, 64, 67 y 76% de las cepas de P. aeruginosa, respectivamente.
El sexto objetivo fue estudiar el genoma completo de las cepas de P. aeruginosa pertenecientes al clon ST155. Se observaron distintos mecanismos de resistencia intrínsecos y alteraciones en sus bombas de expulsión activa; así como la presencia de la isla de patogenicidad del plásmido pUM505 que contiene el gen crpP, descrito recientemente Las variantes de CrpP detectadas en estas P. aeruginosa, mostraban mutaciones en las posiciones catalíticas implicadas en la inactivación del ciprofloxacino (identidad 94-99%) y una localización cromosómica.
Los últimos objetivos fueron detectar y caracterizar los biosurfactantes producidos por Pseudomonas spp. El 97,3% de las cepas de P. aeruginosa y el 32% de las cepas no aeruginosa, principalmente P. putida y P. mendocina, mostraron producción de biosurfactantes mediante el método CTAB-MB agar. Los tres biosurfactantes purificados de dos P. mendocina y una P. aeruginosa mostraron actividad antimicrobiana frente a S. aureus (rango CMI: 0,21-3,38 mg/mL) y P. aeruginosa (0,11-0,42 mg/mL). Los ramnolípidos de P. aeruginosa se asociaron probablemente a la producción de RhlAB y RhlC; mientras que queda pendiente de resolver la caracterización estructural y genética de los biosurfactantes de P. mendocina.
Esta tesis, aporta datos de gran importancia en epidemiología, resistencia a antibióticos y virulencia de Pseudomonas de origen no-clínico con aplicación en salud humana, salud animal y seguridad alimentaria. Y a su vez, la detección de biosurfactantes con actividad antimicrobiana constituye una importante herramienta biotecnológica de aplicación industrial y medioambiental
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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