1,721,028 research outputs found
Sequencing and phylogenetic analysis of human genotype P[6] rotavirus strains detected in Hungary provides evidence for genetic heterogeneity within the P[6] VP4 gene
Although rotavirus genotype P[6] is one of the three most common VP4 specificities associated with human infection, the relatively few sequence data available in public databases suggest that the genetic variability within P[6] might be presently unexplored. Thus far, two human P[6] lineages (M37-like and AU19-like) and a single porcine P[6] lineage (Gottfried-like) have been identified by phylogenetic analysis. Serologic studies demonstrated that these three lineages are antigenically distinct from each other, a finding based on which they were classified into three subtypes, P2A[6] (M37-like), P2B[6] (Gottfried-like), and P2C[6] (AU19-like). To study heterogeneity within this genotype, we selected for molecular characterization a total of six P[6] strains detected during an ongoing surveillance in Hungary. The variable region of the VP4 gene was subjected to sequencing and phylogenetic analysis. Our data indicated that these six strains fell into two phylogenetic lineages distinguishable from the human lineages M37-like and AU19-like and from the porcine lineage Gottfried-like. Further studies are needed to understand whether these two novel lineages are genuine human strains or might have originated from animal strains and to evaluate the antigenic relationship of the novel Hungarian P[6] strains to the three established subtype
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Frequency of norovirus in stool samples from hospitalized children due to acute gastroenteritis in Anatolia, Turkey, 2006-2007
Noroviruses are among the most common causes of sporadic enteritis in childhood. In this pilot study, the frequency of norovirus infection in children in mid-western Turkey was investigated from November 2006 to June 2007. Noroviruses were detected in 17% of samples (15/88) by a combination of 2 different RT-PCR assays, both targeting an overlapping region of the RNA-dependent RNA polymerase gene. By sequence analysis, most strains were characterized as GIIb/Hilversum. One strain was characterized as GII.4/2006a, a variant that appeared worldwide in 2006, while another strain was characterized as a rare genotype, GII.6. This study demonstrates the importance of norovirus in paediatric diarrhoea and suggests the heterogeneity of circulating strains in Turkey. © 2009 Informa UK Ltd All rights reserved
Emergence in 2017–2019 of novel reassortant equine-like G3 rotavirus strains in Palermo, Sicily
Rotavirus A (RVA) is a major etiologic agent of gastroenteritis in children worldwide. Hospital-based surveillance of viral gastroenteritis in paediatric population in Palermo (Italy) from 2017 onwards revealed a sharp increase in G3P[8] RVAs, accounting for 71% of all the RVAs detected in 2019. This pattern had not been observed before in Italy, with G3 RVA usually being detected at rates lower than 3%. In order to investigate this unique epidemiological pattern, the genetic diversity of G3 RVAs identified during a 16-year long surveillance (2004–2019) was explored by systematic sequencing of the VP7 and VP4 genes and by whole genome sequencing of selected G3 strains, representative of the various RVA seasons. Sequence and phylogenetic analyses of the VP7 and VP4 genes revealed the emergence, in 2017 of reassortant equine-like G3P[8], which gradually replaced former G3P[8] strains. The G3P[8] circulating before 2017 showed a Wa-like constellation of genome segments while the G3P[8] that emerged in 2017 had a DS-1-like backbone. On direct inspection of the VP7 and VP4 antigenic epitopes, the equine-like G3P[8] strains possessed several amino acid variations in neutralizing regions compared with vaccine strains. The equine-like G3P[8] RVAs are a further example of the zoonotic impact of animal viruses on human health
Variations on the Author
“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
We 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
We 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
We 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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