1,720,954 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
EFECTO DE LA PODA DE VID SOBRE LOS PARÁMETROS DE CRECIMIENTO Y PRODUCCIÓN DE ENZIMAS LIGNINOLÍTICAS DE Lentinula edodes
Get PDFMECANISMO MOLECULAR DE ACCIÓN DEL SISTEMA DE QUORUM SENSING NprR-NprRB EN LA ESPORULACIÓN DE Bacillus thuringiensis
Get PDFQuorum sensing (QS) es un mecanismo de comunicación bacteriano para regular la expresión génica en respuesta a la densidad celular, a través de moléculas de señalización y proteínas receptoras. En este trabajo se estudió el reconocimiento molecular del receptor de QS NprR con su péptido de señalización NprRB y con el regulador de respuesta Spo0F que participa en la regulación del inicio de la esporulación, todos codificados en el genoma de Bacillus thuringiensis (Bt). Primeramente, se produjo la proteína NprR recombinante utilizando Escherichia coli como sistema de expresión heterólogo. Para lograr el plegamiento y funcionalidad de NprR fue necesario co-expresar las chaperonas DnaK-DnaJ-GrpE y GroEL-GroES. Además, se optimizaron las condiciones de proceso para la producción de NprR utilizando un cultivo en lote alimentado, incrementando 98 veces el rendimiento de NprR con respecto al obtenido en matraz agitado. Se estudió la interacción entre NprR y distintos péptidos de señalización (NprRB) putativos y se encontró que SSKPDIVG, SKPDIVG y SSKPDIV se unieron a NprR con constantes de disociación de 7.19 nM, 28.20 nM y 70.92 nM respectivamente, determinadas por calorimetría de titulación isotérmica; además por espectroscopía de fluorescencia se demostró que la unión del péptido indujo cambios conformacionales en NprR y se observó cooperatividad positiva para la unión del péptido a la proteína.
Nuestros resultados indican que el mecanismo de reconocimiento NprR-NprRB se da a través de un proceso de selección conformacional. Un hallazgo importante del presente trabajo fue que en función de las concentraciones de péptido presentes, diferentes holo-formas del complejo proteína-péptido pueden co-existir. Esto sugiere que la concentración de NprRB es un factor importante para las funciones de NprR. Palabras clave: receptor bifuncional NprR, péptido de señalización NprRB, quorum-sensing, reconocimiento molecular, regulador de respuesta Spo0F, phosphorelay
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
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