1,721,010 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
Identification of neuroendocrine pathways regulating physiological processes in the oyster Crassostrea gigas via the functional characterization of ligand / receptor couples
No full textLes acteurs neuroendocriniens régulant la physiologie des Lophotrochozoaires, groupe frère des Ecdysozoaires parmi les Protostomiens, demeurent peu connus. Grâce à l’émergence récente de ressources génomiques, transcriptomiques et peptidomiques chez l’huître creuse Crassostrea gigas, l’étude des couples ligand(s)/récepteur(s) régulant les fonctions physiologiques est désormais facilitée. Ainsi, par une approche d’endocrinologie inverse consistant à éprouver l’activité d’un panel de ligands potentiels, plusieurs récepteurs couplés aux protéines G (RCPGs), jusqu’alors orphelins ont pu être caractérisés sur le plan fonctionnel. Trois voies de signalisation ont été étudiées : la voie de type cholécystokinine/sulfakinine (CCK/SK) la voie de type calcitonine (CT) et la voie de type dopamine (DA). Grâce à des tests fonctionnels, deux neuropeptides et deux récepteurs de type CCK/SK ont pu être caractérisés. Des tests d’activité biologique in vitro et des expériences de conditionnement alimentaire ont montré la potentielle implication de ces couples dans la régulation de la digestion et de la satiété chez l’huître. Par ailleurs, deux couples neuropeptide/récepteur de type CT ont été caractérisés montrant, à l’image de leurs homologues chez les vertébrés, leur possible rôle dans la régulation hydrique ou ionique. D’autre part, un récepteur activé de manière spécifique par la dopamine et la tyramine a été caractérisé. Ce système de signalisation semble être impliqué dans la médiation du stress et intervenir dans les processus régulateurs de la reproduction au niveau de la gonade. Ainsi, les différents résultats obtenus au cours de ces travaux ont permis d’identifier des couples ligands/récepteurs d’huître homologues de systèmes de signalisation présents chez les Ecdysozoaires et les vertébrés confirmant l’origine de ces systèmes neuroendocriniens depuis l’ancêtre commun des Bilatériens. Les résultats obtenus ont également permis de mieux comprendre comment l’huître intègre les paramètres du milieu et donc s’acclimate aux différentes contraintes environnementales.The neuroendocrine regulators of the physiology of Lophotrochozoa, the sister clade of Ecdysozoa among Protostoma, remain poorly understood. Thanks to the recent emergence of genomic, transcriptomic and peptidomic resources in the Pacific oyster Crassostrea gigas, the functional characterization of ligand/receptor pairs regulating a diversity of physiological functions has been facilitated. Using a reverse endocrinology approach, a number of orphan G Protein-Coupled Receptors (GPCRs) have been functionally characterized. Three signalling systems have been studied in the oyster: The cholecystokinin/sulfakinin (CCK/SK), the calcitonin (CT) and the dopamine (DA) signalling systems. Two CCK/SK receptors and ligands have been characterized. In vitro bioassays and feeding conditions suggested the potential involvement of this signalling system in the regulation of digestion and satiety. Besides, two couples of CT-type peptides and receptors have been characterized showing, as for their vertebrate counterparts, their possible role in the regulation of water and ion balance. A receptor specifically activated by dopamine and by tyramine has also been characterized. This signalling system appeared to be implicated in the mediation of stress and to play a role in the regulatory processes of reproduction in the gonads. This study allowed the characterization in the oyster of ligand receptor pairs homolog to known signalling systems present in Ecdysozoa and vertebrates, thus confirming the origin of these neuroendocrine systems in the common ancestor of Bilateria. The results of this study also contributed to understand how the oyster integrates external parameters and adapts to various environmental constrains
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
Epigenetic regulation of development : eco-evo-devo approach of m6A epitranscriptomes in the oyster Crassostrea gigas
No full textLa méthylation de l’ARN N6-méthyladénosine (m6A) est un nouveau mécanisme de régulation de l’expression des gènes via son implication dans l’épissage, la traduction et la stabilité des transcrits. Cette voie épitranscriptomique, composée de writers, d’erasers, et des readers, régule des étapes clés du développement comme la MZT et la différenciation cellulaire. Cependant, cette voie épitranscriptomique, influencée par l’environnement, montre des différences entre les Vertébrés et Ecdysozoaires étudiés et pose la question de sa conservation dans l’ensemble des Bilatériens et particulièrement chez les Lophotrochozoaires. L’étude de la conservation de la voie épitranscriptomique chez C. gigas a été réalisée par détection de la m6A par dotblot et spectrométrie de masse. Des orthologues de l’ensemble des acteurs de la machinerie ont été caractérisés in silico, et la présence de readers fonctionnels confirmée par RNA pull down/LC-MS2. L’analyse des méthylomes développementaux obtenus par MeRIP-seq montre une dynamique du niveau et de la localisation de la m6A au cours du développement de l’huître. Ces résultats montrent une régulation de la segmentation, de la gastrulation, de la différenciation tissulaire et de la métamorphose par la m6A, chez l’huître creuse. Enfin l’analyse de méthylomes ovocytaires dans des conditions environnementales contrastées démontre une fonction de transmission de trait de vie portée par la m6A chez l’huître. L’ensemble de ce travail a permis de démontrer la conservation du rôle développemental des épitranscriptomes m6A et de leur rôle de vecteur intergénérationnel de traits de vie pour la première fois, à notre connaissance, chez un Lophotrochozoaire.The RNA modification N6-methyladenosine (m6A) is a newly described regulatory layer of gene expression involved in RNA splicing, translation and stability. This epitranscriptomic pathway, composed of writers, erasers and readers, regulates key developmental steps such as MZT and cell differentiation. However, this epitranscriptomic mechanism, which is under environmental influence, shows differences between the Vertebrates and Ecdysozoans examined, which raise the question of the general conservation of an epitranscriptomic pathway in Bilaterian and especially in Lophotrochozoans. Therefore, we investigated the conservation of an m6A pathway in C. gigas by detection of m6A RNA using dotblot and mass spectrometry. Orthologues of all types of actors of the m6A machinery were characterized in silico, and the presence of functional readers was assessed by RNA pull-down/LC-MS2. The profiling of embryo-larval m6A methylomes obtained by MeRIPseq showed that the m6A level and localization were dynamic throughout oyster development. These results show a regulation of oyster segmentation, gastrulation, tissue differentiation and metamorphosis by the m6A. Finally, the study of oocyte methylomes in contrasted environmental conditions demonstrates a life trait transmission function carried by m6A in the oyster. This work demonstrates the conservation of the developmental function of m6A epitranscriptomes and their role as a vector of intergenerational life traits for the first time, to our knowledge, in a Lophotrochozoan
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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