1,720,956 research outputs found
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
A Comparative Evaluation of the Performance of the Viroseq HIV-1 Genotyping System V2.0 Against an in-house Assay Using Specimens from the National HIV Drug Resistance Monitoring Survey in Zimbabwe
No full textThis study was carried out to assess the performance of the Viroseq HIV-1 genotyping
system v2.0 (Celera, Alameda, California, USA) on Zimbabwean samples at the National
Microbiology Reference Laboratory (NMRL) in Harare and to compare the results obtained
with those obtained at a World Health Organization accredited genotyping laboratory in
Entebbe, Uganda, which genotyped the same samples using an in-house method.
Study samples: Thirty eight (38) plasma samples were used in this study. They were selected
from samples stored at NMRL, which had been collected from patients eligible for
commencement on antiretroviral therapy just prior to taking antiretroviral drugs at sentinel
sites for the National HIV Drug Resistance Monitoring Survey in Zimbabwe.
Results: Viral RNA extraction and RT-PCR reactions were successful at first attempt for all
the 38 study samples. The success rates of cycle sequencing reactions using the 7 proprietary
Viroseq sequencing primer mixes on the 38 samples, at first attempt were: Primer A (81.6%),
primer B (86.8), primers C and G (84.2%), Primer D (10.5%), Primer F (73.7%) and Primer
H (94.7%). Thirty seven out of the 38 samples (97.4%) were successfully genotyped.
However, 14 (37.8%) of these pol region consensus sequences obtained were unidirectional.
Thirty two out of the 37 (86.5%) Viroseq genotyped samples clustered in pairs with their
corresponding sample sequences generated in Uganda with bootstrap support values ≥70
(median bootstrap support value, 97.5: range 31-99) on neighbour joining tree phylogenetic
analysis. All of the genotyped study samples were found to be HIV-1 subtype C (n=37).
Nineteen of the 37 (48.6%) genotyped samples had at least one drug resistance mutation
detected by either Viroseq or the Ugandan in-house assay. The detected mutations as reported
by the two genotyping systems were fully concordant in 11/19 (57.9%), partially concordant
in 2/19 (10.5%) and discordant in 6/19 (31.6%) of these specimens with drug resistance
mutations. Overall, all the reports generated by the two systems with or without any
mutations were 78.4% fully concordant, 16.2% partially concordant and 5.4% discordant.
Conclusions: The Viroseq system can be reliably used to genotype Zimbabwean samples by
adequately trained operators at NMRL. Sequencing Primer D is not suitable for sequencing
Zimbabwean subtype C isolates due to its high sequencing reaction failure rate
A comparative evaluation of the performance of the Viroseq HIV-1 genotyping system v2.0 against an in-house assay using specimens from the national HIV drug resistance monitoring survey, in Zimbabwe.
No full textThis study was carried out to assess the performance of the Viroseq HIV-1 genotyping
system v2.0 (Celera, Alameda, California, USA) on Zimbabwean samples at the National
Microbiology Reference Laboratory (NMRL) in Harare and to compare the results obtained
with those obtained at a World Health Organization accredited genotyping laboratory in
Entebbe, Uganda, which genotyped the same samples using an in-house method.
Study samples: Thirty eight (38) plasma samples were used in this study. They were selected
from samples stored at NMRL, which had been collected from patients eligible for
commencement on antiretroviral therapy just prior to taking antiretroviral drugs at sentinel
sites for the National HIV Drug Resistance Monitoring Survey in Zimbabwe.
Results: Viral RNA extraction and RT-PCR reactions were successful at first attempt for all
the 38 study samples. The success rates of cycle sequencing reactions using the 7 proprietary
Viroseq sequencing primer mixes on the 38 samples, at first attempt were: Primer A (81.6%),
primer B (86.8), primers C and G (84.2%), Primer D (10.5%), Primer F (73.7%) and Primer
H (94.7%). Thirty seven out of the 38 samples (97.4%) were successfully genotyped.
However, 14 (37.8%) of these pol region consensus sequences obtained were unidirectional.
Thirty two out of the 37 (86.5%) Viroseq genotyped samples clustered in pairs with their
corresponding sample sequences generated in Uganda with bootstrap support values ≥70
(median bootstrap support value, 97.5: range 31-99) on neighbour joining tree phylogenetic
analysis. All of the genotyped study samples were found to be HIV-1 subtype C (n=37).
Nineteen of the 37 (48.6%) genotyped samples had at least one drug resistance mutation
detected by either Viroseq or the Ugandan in-house assay. The detected mutations as reported
by the two genotyping systems were fully concordant in 11/19 (57.9%), partially concordant
in 2/19 (10.5%) and discordant in 6/19 (31.6%) of these specimens with drug resistance
mutations. Overall, all the reports generated by the two systems with or without any
mutations were 78.4% fully concordant, 16.2% partially concordant and 5.4% discordant.
Conclusions: The Viroseq system can be reliably used to genotype Zimbabwean samples by
adequately trained operators at NMRL. Sequencing Primer D is not suitable for sequencing
Zimbabwean subtype C isolates due to its high sequencing reaction failure rate
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
A comparative evaluation of the performance of the Viroseq HIV-1 genotyping system v2.0 against an in-house assay using specimens from the national HIV drug resistance monitoring survey, in Zimbabwe.
No full textThis study was carried out to assess the performance of the Viroseq HIV-1 genotyping
system v2.0 (Celera, Alameda, California, USA) on Zimbabwean samples at the National
Microbiology Reference Laboratory (NMRL) in Harare and to compare the results obtained
with those obtained at a World Health Organization accredited genotyping laboratory in
Entebbe, Uganda, which genotyped the same samples using an in-house method.
Study samples: Thirty eight (38) plasma samples were used in this study. They were selected
from samples stored at NMRL, which had been collected from patients eligible for
commencement on antiretroviral therapy just prior to taking antiretroviral drugs at sentinel
sites for the National HIV Drug Resistance Monitoring Survey in Zimbabwe.
Results: Viral RNA extraction and RT-PCR reactions were successful at first attempt for all
the 38 study samples. The success rates of cycle sequencing reactions using the 7 proprietary
Viroseq sequencing primer mixes on the 38 samples, at first attempt were: Primer A (81.6%),
primer B (86.8), primers C and G (84.2%), Primer D (10.5%), Primer F (73.7%) and Primer
H (94.7%). Thirty seven out of the 38 samples (97.4%) were successfully genotyped.
However, 14 (37.8%) of these pol region consensus sequences obtained were unidirectional.
Thirty two out of the 37 (86.5%) Viroseq genotyped samples clustered in pairs with their
corresponding sample sequences generated in Uganda with bootstrap support values ≥70
(median bootstrap support value, 97.5: range 31-99) on neighbour joining tree phylogenetic
analysis. All of the genotyped study samples were found to be HIV-1 subtype C (n=37).
Nineteen of the 37 (48.6%) genotyped samples had at least one drug resistance mutation
detected by either Viroseq or the Ugandan in-house assay. The detected mutations as reported
by the two genotyping systems were fully concordant in 11/19 (57.9%), partially concordant
in 2/19 (10.5%) and discordant in 6/19 (31.6%) of these specimens with drug resistance
mutations. Overall, all the reports generated by the two systems with or without any
mutations were 78.4% fully concordant, 16.2% partially concordant and 5.4% discordant.
Conclusions: The Viroseq system can be reliably used to genotype Zimbabwean samples by
adequately trained operators at NMRL. Sequencing Primer D is not suitable for sequencing
Zimbabwean subtype C isolates due to its high sequencing reaction failure rate
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