1,721,019 research outputs found
Development of an image processing algorithm for the preliminary quantification of intracellular contents of polyhydroxyalkanoates in cultures of Cupriavidus necator
No full textSe desarrolló un algoritmo basado en el análisis cuantitativo de imágenes, para la estimación cuantitativa del contenido intracelular de polihidroxialcanoatos (PHA’s) en cultivos celulares a partir de imágenes de microscopía de fluorescencia. Para ello se identificaron los parámetros de crecimiento y biosíntesis de PHA de la cepa bacteriana Cupriavidus necator DSM 545. Posteriormente se desarrolló un protocolo montaje de muestras mediante camas de agarosa en juntas tóricas, y se estableció el protocolo de adquisición de imágenes para alimentar el algoritmo. El método propuesto permitió generar cuatro data sets cada uno de cien pares de imágenes de microscopía confocal y de fluorescencia. Como resultado se obtuvo un algoritmo de cuantificación funcional basado en la técnica de segmentación de Watershed y filtrado estadístico de data sets que consiguió cuantificar la concentración intracelular de PHA en g/L con un porcentaje de error medio del 18.6% respecto a la cuantificación mediante cromatografía de gases. Se constituye así un método alternativo de cuantificación de PHA, rápido, de menor costo y que no involucra el uso de sustancias químicas perjudiciales para el medio ambiente y la salud humana.Instituto de Ciencias Biomédicas - Universidad de Sao PauloBioingenieroPregradoAn algorithm based on quantitative image analysis was developed for the quantitative estimation of the intracellular content of polyhydroxyalkanoates (PHA's) in cell cultures from fluorescence microscopy images. For this, the growth and biosynthesis parameters of PHA of the Cupriavidus necator DSM 545 bacterial strain were identified. Subsequently, a sample assembly protocol was developed using agarose beds in O-rings, and the image acquisition protocol was established to feed the algorithm. . The proposed method allowed the generation of four data sets each of one hundred pairs of confocal and fluorescence microscopy images. As a result, a functional quantification algorithm based on the Watershed segmentation technique and statistical filtering of data sets was obtained, which managed to quantify the intracellular concentration of PHA in g/L with a mean error percentage of 18.6% compared to quantification by chromatography. of gases. Thus, an alternative method of quantification of PHA is constituted, fast, of lower cost and that does not involve the use of harmful chemical substances for the environment and human health
Reseña: María Elena Bedoya Hidalgo, Jimena Perry Posada, Manuel Salge Ferro (ed.), Comunidades digitales, museos e historia pública: Experiencias en torno a América Latina
No full textMaría Elena Bedoya Hidalgo, Jimena Perry Posada, Manuel Salge Ferro (ed.), Comunidades digitales, museos e historia pública: Experiencias en torno a América Latina, Quito/Bogotá, USFQ Press/Editorial Universidad Externado de Colombia, 2023, 313 p. Depuis une perspective pluridisciplinaire et mettant l’accent sur l’expérience de la crise sanitaire, cet ouvrage se présente comme un observatoire dans lequel les humanités numériques – et leurs communautés – occupent une place majeure. La conjon..
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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