1,720,965 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
New approaches based on complexity measures for the detection of short sequences in bioinformatics
No full textFil: Raad, Jonathan. Universidad Nacional del Litoral. Facultad de ingeniería y Ciencias Hídricas; Argentina.El aprendizaje maquinal ha tenido un gran desarrollo en los últimos años y ha permitido resolver una gran cantidad de problemas en las más diversas disciplinas, aunque aun quedan grandes desafíos por resolver cuando los datos presentan un alto grado de desbalance de clases o tienen muy pocos
datos etiquetados. Un caso particular de aplicación donde se presentan desafíos como estos es en la predicción computacional de secuencias de microARN. Este, también llamado microARN maduro, es una pequeña molécula de ARN no codificante la cual puede regular la expresión de los genes.
En los últimos años, se ha desarrollado una gran cantidad de métodos que intentan detectar nuevos microARN utilizando información principalmente de su estructura. El principal inconveniente de estos métodos es que utilizan características basadas principalmente en la estructura del precursor (pre-miARN) sin incluir la información del miARN maduro, que se encuentra codificada en forma secuencial. De esta manera, se pierde información muy valiosa que podría utilizarse para mejorar la predicción de nuevos pre-miARN y disminuir a su vez el número de falsos positivos.
Recientemente se propusieron enfoques basados en aprendizaje profundo como un método para la extracción automática de características. Sin embargo, éstos tienen aún importantes limitaciones prácticas cuando deben aplicarse a tareas de predicción real. Para poder permitir la predicción de nuevos miARNs en genomas completos, en esta tesis se realizaron dos grandes aportes. En primer lugar, se desarrollaron tres nuevas características basadas en medidas de complejidad del miARN maduro, las cuales permiten reducir significativamente el número de falsos positivos. En segundo lugar, se desarrolló el primer algoritmo de aprendizaje profundo de extremo a extremo para la predicción de pre-miARNs en genomas completos. Machine learning has had a great development in recent years and has allowed solving a large number of problems in the most diverse disciplines, although there are still great challenges to be solved when the data presents a high degree of class imbalance or has few labeled data. A particular case of application where challenges like these present themselves is in the computational prediction of microRNA sequences. This, also called mature microRNA, is a small non-coding RNA molecule which can regulate gene expression.
In recent years, a large number of methods have been developed that try to detect new microRNAs using information mainly from their structure. The main drawback of these methods is that they use characteristics based mainly on the structure of the precursor (pre-miRNA) without including the information of the mature miRNA, which is sequentially encoded. In this way, very valuable information is lost that could be used to improve the prediction of new pre-miRNAs and, in turn, reduce the number of false positives.
Deep learning-based approaches have recently been proposed as a method for automatic feature extraction. However, they still have important practical limitations when applied to real forecasting tasks. In order to allow the prediction of new miRNAs in complete genomes, two major contributions were made in this thesis. First, three new features were developed based on complexity measures of the mature miRNA, which allow to significantly reduce the number of false positives. Second, the first end-to-end deep learning algorithm for the prediction of pre-miRNAs in whole genomes was developed. Consejo Nacional de Investigaciones Científicas y TécnicasUniversidad Nacional del Litora
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
Complexity measures of the mature miRNA for improving pre-miRNAs prediction
No full textMotivationThe discovery of microRNA (miRNA) in the last decade has certainly changed the understanding of gene regulation in the cell. Although a large number of algorithms with different features have been proposed, they still predict an impractical amount of false positives. Most of the proposed features are based on the structure of precursors of the miRNA (pre-miRNA) only, not considering the important and relevant information contained in the mature miRNA. Such new kind of features could certainly improve the performance of the predictors of new miRNAs.ResultsThis paper presents three new features that are based on the sequence information contained in the mature miRNA. We will show how these new features, when used by a classical supervised machine learning approach as well as by more recent proposals based on deep learning, improve the prediction performance in a significant way. Moreover, several experimental conditions were defined and tested in order to evaluate the novel features impact in situations close to genome-wide analysis. The results show that the incorporation of new features based on the mature miRNA allow to improve the detection of new miRNAs independently of the classifier used.Fil: Raad, Jonathan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Stegmayer, Georgina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Milone, Diego Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; Argentin
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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