1,720,979 research outputs found
Rotavirus gastroenteritis in italian children: can the severity of the symptoms be related to the infecting virus?
No full textThe aim of our study was to determine whether the severity of rotavirus gastroenteritis may be related to the different characteristics of infecting viral strains. The severity of clinical symptoms in 401 children with acute rotavirus gastroenteritis was assessed using a scoring system for frequency and duration of vomiting, diarrhea, and fever, as well as the patients' requirements for intravenous rehydration. Rotavirus strains were characterized by determining the electropherotype of their double-stranded RNA, the G type and subgroup by a panel of monoclonal antibodies, and the P type by reverse transcription-polymerase chain reaction. Strains with a short electropherotype, G2P[4] type, and subgroup I were associated with more-severe gastroenteritis and affected children older than those infected with strains with a long electropherotype, G1P[8] or G4P[8] type, and subgroup II. Minor differences in clinical symptoms were also detected in children infected with different long electropherotypes and with G1P[8] and G4P[8] specificities
Identification of human rotavirus strains with the P[14] genotype by PCR
No full textA seminested PCR typing assay has been extended to identify rotavirus strains with the P[14] genotype. The specificity of the method was confirmed by Southern hybridization and by restriction analysis with the enzyme AluI. One out of four human rotavirus (HRV) strains with unusual subgroup-electropherotype linkage but none out of 50 HRV strains with usual linkage was typed as P[14]
The iron-responsive regulator Fur is transcriptionally autoregulated and not essential in Neisseria meningitidis
No full textFur is a well-known iron-responsive repressor of gene transcription, which is used by many bacteria to respond to the low-iron environment that pathogens encounter during infection. The fur gene in Neisseria meningitidis has been described as an essential gene that may regulate a broad array of genes. We succeeded in obtaining an N. meningitidis mutant with the fur gene knocked out and used it to undertake studies of fur-mediated iron regulation. We show that expression of both Fur and the transferrin binding protein Tbp2 is iron regulated and demonstrate that this regulation is Fur mediated for the Tbp2 protein. Footprinting analysis revealed that Fur binds to two distinct sites upstream of its coding region with different affinities and that these binding sites overlap two promoters that differentially control transcription of the fur gene in response to iron. The presence of two independently regulated fur promoters may allow meningococcus to fine-tune expression of this regulator controlling iron homeostasis, possibly during infection
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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