1,720,971 research outputs found
CYP2D6 genotyping by a multiplex primer extension reaction
No full textwe designed a cost-effective and technically
feasible CYP2D6 genotyping technique through a
2-step assay that provides a straightforward interpretation of results. It allows detection of 11 of the most relevant polymorphic positions, the assessment of wholegene deletion and duplication, and unlike most available typing methods, the allele composition of the gene duplication
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
Pharmacogenetic variation at CYP2C9, CYP2C19, and CYP2D6 at global and micro-geographic scales
No full textObjectives
CYP2C9, CYP2C19, and CYP2D6 belong to a subfamily of cytochrome P450 (CYP)
enzymes, associated mainly with the metabolism of exogenous compounds in the human
body. The genes coding for these enzymes are highly polymorphic and thus of major
pharmacogenetic importance. By systematically retrieving data from the literature and
genotyping new population samples, we aimed at describing the worldwide distribution
of genetic variation at these loci. We created a comprehensive resource of frequency data
for the most important CYP2C9, CYP2C19, and CYP2D6 genetic variants in 129, 146,
and 55 different population samples, respectively. Furthermore, we showed how
demographic history can affect pharmacogenetic variation at a micro-geographic scale by
analysing regional samples from Finland, which represents a well-known genetic isolate.
Methods
Data were obtained from the literature from 1991 to 2007 as well as by genotyping new
population samples at four CYP2C9, two CYP2C19 and twelve CYP2D6 variable sites
affecting enzymatic activity.
Results and conclusions
Our study shows that: (i) altered activity variants of CYP2C9, CYP2C19, and CYP2D6
occur globally in all geographic regions, reaching extremely high frequencies in some
populations; (ii) each of the CYP genes studied shows a distinct geographic pattern of
variation; (iii) population substructure can strongly affect the variation seen in 3 pharmacogenetic loci; and (iv) several geographic regions of pharmacogenetic interest are still poorly characterized
CYP2D6 worldwide genetic variation shows high frequency of altered activity variants and no continental structures
No full textBackground and objective CYP2D6, a member of the
cytochrome P450 superfamily, is responsible for the
metabolism of about 25% of the commonly prescribed
drugs. Its activity ranges from complete deficiency to
excessive activity, potentially causing toxicity of medication
or therapeutic failure with recommended drug dosages.
This study aimed to describe the CYP2D6 diversity at the
global level.
Methods A total of 1060 individuals belonging to 52
worldwide-distributed populations were genotyped at
12 highly informative variable sites, as well as for gene
deletion and duplications. Phenotypes were predicted on
the basis of haplotype combinations.
Results and conclusions Our study shows that (i)
CYP2D6 diversity is far greater within than between
populations and groups thereof, (ii) null or low-activity
variants occur at high frequencies in various areas of the
world, (iii) linkage disequilibrium is lowest in Africa and
highest in the Americas. Patterns of variation, within
and among populations, are similar to those observed for
other autosomal markers (e.g. microsatellites and protein
polymorphisms), suggesting that the diversity observed
at the CYP2D6 locus reflects the same factors affecting
variation at random genome markers
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
- …
