1,720,956 research outputs found
Quantitation of feline immunodeficiency proviruses in doubly infected cats using competitive PCR and a fluorescence-based RFLP
No full textA nested polymerase chain reaction assay, which amplifies a region of the gag gene, was developed for the direct detection of feline immunodeficiency virus (FIV) DNA sequences in the blood of infected cats. This method detects as few as ten copies of a plasmid containing the whole genome of the FIV-Pet isolate on agarose gel. To distinguish two FIV isolates in double infected cats: we devised an RFLP analysis on PCR amplified products exploiting sequence differences in the gag gene of the two strains. To quantitate the two strains, a fluorescent inner-sense primer was used in the second amplification step. Amplicons were subsequently digested, heat-denatured and loaded on a polyacrylamide gel in an automated DNA sequencer. The proportion of the two isolates was determined using the laser-excited fluorescence of labelled strain specific fragments. These data were used to extrapolate the numbers of proviral genomes from the total viral load as estimated by using a competitive PCR assay, These sensitive and specific assays complement virological detection of FIV and enable superinfection studies to be evaluated; a prerequisite for the testing of live attenuated immunodeficiency virus vaccines
PARTIAL NUCLEOTIDE SEQUENCING OF 6 SUBTYPE 2C HEPATITIS-C VIRUSES DETECTED IN ITALY
No full textThe great majority of 121 hepatitis C virus (HCV) isolates obtained from 117 Italian patients with community-acquired infection could readily be typed by genotype-specific PCR. Subtype Ib was dominant (74 isolates); subtypes 2b, 2a, and la followed, with 19, 14, and 8 isolates, respectively. The six isolates that remained untyped by this method were classified as subtype 2c on the basis of sequence analysis of PCR amplicons obtained from the core and NS5 genes. These findings indicate that HCV subtype 2c has a relatively high prevalence in Italy. Sequencing the core region from positions 160 to 259 is sufficient to distinguish subtype 2c from other known HCV genotypes
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
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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