1,720,956 research outputs found
A influência da microbiota de doadores de córnea em casos de infecção pós-transplante
Get PDFO transplante de córneas proporciona a recuperação da visão a um custo muito baixo. Atualmente, é o principal tratamento para pessoas que apresentam distúrbios de curvatura ou transparência da córnea. No entanto, no Brasil, não há um protocolo unificado sobre os meios de preservação, tempo de armazenamento e antibióticos utilizados. A preocupação com a eficiência dos meios de preservação, na descontaminação das córneas, é de que agentes patogênicos sejam transferidos aos receptores de transplantes, causando infecções oculares após o transplante. Este artigo realizou um levantamento de referências teóricas, já publicadas e disponibilizados por plataformas digitais governamentais, assim como periódicos científicos buscados pelo portal de periódicos da Capes, e PubMed. O levantamento mostrou que estudos baseados em cultivo de microrganismos, trazem Staphylococcus cagulase negativa em 30 a 100% das amostras isoladas de conjuntivas. Em menor quantidade estão Streptococcus, Corynebacterium e Propionibacterium. Bactérias Gram-negativas aparecem em número muito inferior, representadas pelos gêneros Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus e Acinetobacter. Já os resultados baseados em técnicas independentes de cultivo trazem Pseudomonas como a principal colonizadora da conjuntiva, contrariando os resultados obtidos por técnicas dependentes de cultivo. Também, apresentam uma diversidade muito maior de colonizadores, mostrando um potencial campo de estudos. O globo ocular pode ter uma diversidade muito maior de espécies e potencias agentes patogênicos, do que era esperado. Os principais meios de preservação utilizados no Brasil, levam os antimicrobianos gentamicina e estreptomicina em sua composição. A utilização desses antibióticos já se mostra controversa, a medida em que muitas espécies bacterianas isoladas dos meios de preservação e de infecções pós transplante, são resistentes a gentamicina e algumas, resistentes a gentamicina e estreptomicina. A necessidade de se rever os antimicrobianos utilizados nos meios de preservação, seja por sua eficiência ou pelo grupo alvo a ser atingido, já que estudos indicaram a presença de uma grande quantidade de bactérias Gram-negativas no bioma ocular, pode levar ao desenvolvimento de um protocolo unificado para utilização no Brasil.Corneal transplantation provides visual restoration at a low cost. Currently transplantation is the main treatment for corneal curvature issues and corneal transparency disorders. However, Brazil lacks a unified protocol on preservation, storage, and antibiotic treatment of corneal tissue. The main concern with the efficiency of preservation and decontamination of corneas is the possibility of postoperative eye infection due to pathogen transference. This article performed a survey of theoretical references that have been published and made available in governmental digital platforms, as well as scientific journals found in Capes and PubMed resources. This survey reveals that studies based on microorganism cultures presented coagulase-negative Staphylococcus in 30 to 100% of conjunctival isolated samples. Streptococcus, Corynebacterium, and Propionibacterium were found in smaller amounts. The number of gram-negative bacteria, such as Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus and Acinetobacter, was much lower in this kind of study. On the other hand, studies based on independent cultivation techniques showed Pseudomonas as the main conjunctival colonizer, contrary to the results obtained by cultivation-dependent techniques. These studies also show greater variety of colonizers, which could be a new field of study, as the human eye might have more species of bacteria and pathogens than anticipated. The main means of corneal preservation used in Brazil contain the antimicrobials gentamicin and streptomycin in their composition. The use of these antibiotics is controversial, as many bacterial species isolated from preservation means and postoperative infections are resistant to gentamicin and some resistant to both gentamicin and streptomycin. These studies presenting a large quantity of gram-negative bacteria in the ocular biome show that it is necessary to reassess the antimicrobials used in corneal preservation, which can lead to the development of a unified protocol to be used in Brazil
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
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
Influence of donor microbiota and of graft storage on corneal transplantation
Get PDFIntrodução: O transplante de córneas é o principal tratamento para pessoas que apresentam distúrbios de curvatura ou transparência da córnea. No Brasil, não há protocolo unifcado para meios de preservação, tempo de armazenamento e antibióticos utilizados. A preocupação é a de que patógenos possam ser transferidos aos receptores de transplantes. Objetivo: Realizar o levantamento da microbiota ocular de doadores de córneas a fm de verifcar uma possível correlação com infecções em receptores e, dessa forma, auxiliar na melhoria de metodologias e protocolos de armazenamento de córneas. Método: Foi conduzido a partir de revisão da literatura, nas bases de dados PubMed, SciELO e nos portais: periódicos da CAPES, Anvisa, Ministério da Saúde e ABTO, entre 2018 e 2020. Resultados: Estudos baseados em cultivo de microrganismos trazem Staphylococcus coagulase negativa (SCN) de 30% a 100% das amostras isoladas de conjuntivas. Em menor quantidade estão Streptococcus, Corynebacterium e Propionibacterium. Bactérias Gramnegativas aparecem em número inferior, representadas pelos gêneros Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus e Acinetobacter. Já as técnicas independentes de cultivo trazem Pseudomonas como a principal colonizadora da conjuntiva. Também apresentam uma diversidade maior de colonizadores, mostrando um potencial campo de estudos, no qual a superfície ocular pode ter uma diversidade muito maior de espécies e potenciais agentes patogênicos. Os principais meios de preservação utilizados no Brasil levam os antimicrobianos gentamicina e estreptomicina em sua composição, porém estudos têm mostrado que as bactérias presentes nos meios de preservação são resistentes a esses antibióticos. Conclusões: Os dados apontam para a necessidade de reavaliação da efciência desses meios de preservação na descontaminação das córneas para transplante.Introduction: Corneal transplantation it is the main treatment for people who have corneal curvature or transparency disorders. In Brazil, there is no unified protocol on the means of preservation, storage time and antibiotics used. The concern is that pathogens are transferred to transplant recipients, causing eye infections after transplantation. Objective: Examine ocular microbiota of corneal donors, to verify a possible correlation with infections in recipients and thus assist in improving corneal storage methodologies and protocols. Method: Literature review conducted in PubMed, SciELO and the following websites: CAPES Journals, Anvisa, Brazilian Ministry of Health and ABTO, between 2018 and 2020. Results: Studies based on microorganism’s cultivation show coagulase negative Staphylococcus in 30% to 100% of samples isolated from conjunctiva. In lesser quantities are Streptococcus, Corynebacterium and Propionibacterium. Gram-negative bacteria appear in much lower numbers, represented by the genera Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus and Acinetobacter. On the other hand, results based on independent cultivation techniques bring Pseudomonas as the main colonizer of the conjunctiva. Also, they have a much greater diversity of colonizers, showing a potential field of study. The ocular surface may have a much greater diversity of species and potential pathogens than was expected. The main means of preservation used in Brazil contain the antimicrobials gentamicin and streptomycin in their composition; however, several studies have shown that bacteria present in the means of preservation are resistant to these antibiotics. Conclusions: These data point to the need for a reassessment of the efficiency of these means of preservation in decontaminating corneas for transplantation
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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