1,720,975 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
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 transient postnatal exposure to xenoestrogens programs long- term cardiac alterations: Role of microRNAs
No full textA worldwide increase in the burden of non-communicable diseases with developmental origin, such as cardiovascular diseases, is currently observed. Epidemiological and experimental studies indicate that exposure to challenges during early developmental life increases the risk of developing non-communicable diseases later in life. Among these challenges, environmental toxicants, such as endocrine-disrupting chemicals, have been shown to have critical impact on lifelong health. However, the role of such early transient exposure on the heart is poorly studied. Therefore, using a model of rats exposed postnatally and transiently to estradiol benzoate (EB), we aimed at determining whether an early transient postnatal exposure to EDCs has effects on the
adult heart and at identifying the molecular mechanisms in cardiac pathogenesis.
We found that an early transient postnatal exposure to EB induced cardiac hypertrophy in adulthood. Prompting for a search of the underlying mechanisms, we highlighted a subset of micro-RNAs that were downregulated. Among the pathways predicted to be impacted by this modification, the RAS/MAPK signaling pathway was identified. To verify the impact of microRNA deregulation on this pathway, we measured the expression level of different proteins involved in this signaling and regulating critical cellular mechanisms in the heart such as cell survival. We thus highlighted decreased AKT levels, and increased Cleaved Caspase-3 levels in the adult heart of animals exposed postnatally to EB. We next evaluated the potential origins for such microRNAs downregulations and highlighted decreased DGCR8 expression, which could induce altered microRNAs biogenesis. Also, owing the fact that microRNAs maturation can be influenced by estrogens through estrogens receptors, we discovered that GPR30 and EGFR were both downregulated. In conclusion, our work highlighted the long-term programming of cardiac hypertrophy by an early and transient exposure to xenoestrogens and identified microRNAs
alteration as a potential underlying mechanism
Effets cardio-vasculaires des expositions environnementales et rôle de l'épigénétique
No full textContexte
Les recherches concernant les origines développementales de la santé et des
maladies (DOHad) affirment que le développement d'un organisme ne dépend
pas uniquement de son héritage génétique. Celui-ci est également influencé par
les évènements environnementaux auxquels un foetus est exposé, tels le stress,
les maladies et habitudes alimentaires maternelles, ou des toxiques et
perturbateurs endocriniens. Tous ces éléments, sans changer la séquence
primaire de l’ADN, modifient l'expression des gènes et accroissent la possibilité
d'engendrer des maladies non transmissibles à l'âge adulte. Ces phénomènes de
changements d'expression sont en partie liés à l'épigénétique qui agit via des
mécanismes de méthylation d'ADN, de modifications post-traductionnelles des
histones et des ARNs non-codants.
Objectif
Etudier le rôle des divers mécanismes, avec ou sans liens épigénétiques, dans la
programmation des dysfonctions cardiovasculaires, sous l'influence de
perturbateurs endocriniens et toxiques environnementaux.
Méthode
Revue de littérature à partir de 3 recherches issues de la base de données
PubMed, au travers des mots clefs ci-dessous. A partir d'une méthode en
entonnoir, 121 des 328 articles initiaux, publiés entre 1998 et 2017, sont
retenus.
Résultats
Diverses expositions à des perturbateurs endocriniens et des toxiques, sans
implications de l'épigénétique, sont à la base de maladies cardiovasculaires. Six
familles englobant les habitudes de vie, les métaux et métalloïdes, les polluants
organiques persistants, les matières plastiques et autres produits industriels,
ainsi que des toxiques naturels, causent ces pathologies. Elles engendrent
majoritairement des troubles du rythme cardiaque par modification des flux
ioniques, un stress oxydatif endovasculaire via une augmentation de substrats
oxygénoréactifs, une hypertension artérielle et de l'athérosclérose, ainsi qu'un
risque accru d'infarctus du myocarde.
Des sous-membres de ces mêmes familles jouent également un rôle dans la
prédisposition à des maladies cardiovasculaires avec une origine épigénétique.
Les mécanismes les plus fréquemment identifiés sont les changements dans la
méthylation et l'acétylation de l'ADN. Ils affectent particulièrement les molécules
impliquées dans l'immunorégulation et la cardiogenèse. Ces altérations
engendrent, d'une part, un état inflammatoire anormal capable de générer
majoritairement de l'athérosclérose et, d'autre part, des malformations
cardiaques.
Conclusion
Cette étude traite d'un problème de santé publique majeur, les maladies
cardiovasculaires associées à l'environnement. Elle permet une meilleure
compréhension des dysfonctions cardiovasculaires liées à l'environnement et de
leurs mécanismes épigénétiques sous-jacents, étant majoritairement des
modifications de la méthylation et l'acétylation de l'ADN. De ce fait, divers
champs d'application s'ouvrent face à cette nouvelle manière de considérer
l'origine des maladies. Un schéma de prévention novateur pourrait se déployer
en parallèle aux nouvelles possibilités thérapeutiques afin de réduire les couts
immenses engendrés par les maladies cardiovasculaires
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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