1,721,032 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
Proteomic approaches for biological fluids exosomes analysis for biomarker discovery
No full textUn biomarqueur est une molécule (ou un ensemble de molécules) présente dans l’organisme qui témoigne de l’apparition d’un processus pathologique. Il permet ainsi de dépister une maladie, d’en prédire sa gravité ou encore d’évaluer l’efficacité d’un traitement. Les liquides biologiques représentent des milieux de choix pour la recherche de biomarqueurs en pathologie humaine car leur collection est habituelle dans la prise en charge des patients et moins invasive comparée aux biopsies d’organes ou de tissus. Dans cette thèse, nous nous sommes intéressés plus particulièrement aux exosomes présents dans ces liquides biologiques. Les exosomes sont des nanovésicules dont le diamètre est compris entre 30 et 100 nanomètres. Ils sont sécrétés par tous les types cellulaires et contiennent des protéines cytoplasmiques et membranaires spécifiques de leur cellule d’origine. L’intérêt majeur des exosomes isolés à partir des liquides biologiques, est qu’ils constituent une source de biomarqueurs. Ils peuvent donc être assimilés à une « biopsie liquide ». L’analyse des exosomes pourrait compléter utilement des examens classiques de dépistage, de diagnostic et de suivi d’une pathologie. Dans le cadre de projet de cette thèse, nous avons appliqué des techniques de protéomique à haut débit pour l’analyse des exosomes. Nous nous sommes tout d’abord intéressés à l’analyse du profil protéique des exosomes urinaires dans le contexte de deux pathologies du tractus urinaire : la cystinurie et le cancer du rein. La cystinurie est une néphropathie lithiasique d’origine génétique pour laquelle il y a peu de marqueurs biologiques pouvant prédire son évolution vers l’insuffisance rénale terminale. Nous avons développé une méthode de préparation des exosomes urinaire permettant d’analyser de façon reproductible leurs profils protéiques. Nous avons appliqué cette méthode à huit patients cystinuriques et comparé les résultats aux profils obtenus chez dix sujets sains. Un panel de 38 protéines différentiellement exprimé dans les exosomes des patients a été identifié et en partie validé par Western blot. Concernant le cancer du rein à cellules claires pour lequel le diagnostic nécessite des prélèvements invasifs par biopsie, nous avons analysé les exosomes urinaires de huit patients avant et après néphrectomie. Nous avons ainsi pu mettre en évidence un panel de 25 protéines surexprimées dans les exosomes des patients. Enfin, le dernier volet de cette thèse a été consacré à l’analyse des exosomes du lavage broncho-alvéolaire provenant de patients MV, maladie d’origine génétique qui atteint principalement les poumons. L’analyse des exosomes de lavage broncho-alvéolaire pourrait permettre de donner un éclairage nouveau sur la physiopathologie de la maladie. Nous avons réalisé la comparaison des profils protéiques des exosomes de quatre patients MV, et six patients asthmatiques. L’ensemble des résultats obtenus au cours de cette thèse montre que l’analyse protéomique des exosomes issus de fluides biologiques peut aider la recherche de biomarqueurs diagnostics ou pronostics de maladies.A biomarker is a molecule (or a cluster of molecule) which will reflect the occurrence of a pathological state, giving us the ability to detect a disease, to predict its severity or to assess drug efficiency. Biological fluids are the golden standards for biomarker research in human as they are routinely collected for patients’ follow-up and are less invasive than biopsies. During my PhD, I focused on exosomes that can be found in these biological fluids. Exosomes are nanovesicles with a diameter ranging between 30 and 100 nanometers. Exosomes are secreted by all cell types and harbor cytoplasmic and membranous proteins specific of their cells of origins. One of the major interest of exosomes enriched from biological fluids is that they represent a valuable source of biomarkers. They can be considered as a « liquid biopsy ». Their analysis could complete classical diagnosis and follow-up tools. In this project, we applied high resolution, high throughput proteomic techniques for exosomes analysis. We firstly focused on protein profiles in urinary exosomes in the context of two urinary tract diseases: cystinuria and kidney cancer. Cystinuria is an inherited autosomal recessive disease that is characterized by the formation of cystine stones in the kidneys. To date, there are no markers to predict the evolution toward end stage renal disease. We developed a method to prepare exosomes in order to reproducibly analyze their protein profiles. We applied this method to eight cystinuria patients and compared their profiles to those of ten healthy subjects. A panel of 38 differentially expressed proteins in patients were found and validated by western blots. We also applied this method to patients with clear cell renal cell carcinoma, for which invasive biopsies are necessary for clear diagnosis. We analyzed urinary exosomes form eight patients before and after nephrectomy. We were able to highlight 25 overexpressed proteins in patients’ exosomes. Eventually, the last part of my thesis was dedicated to the analysis of exosomes enriched from bronchoalveolar lavage fluid collected in cystic fibrosis patients, a disease that affects mostly the lungs. Bronchoalveolar lavage fluid exosomes analysis could give a new insight on the mechanisms of this disease. We compared protein profiles in exosomes from four cystic fibrosis patients and six asthmatic patients. The whole point of this work is to show that proteomic analysis of exosomes isolated from biological fluids could become a golden standard for the discovery of diagnosis or prognosis biomarkers
New correctors of the protein F508del-CFTR in the context of cystic fibrosis
No full textLa mucoviscidose est la maladie génétique récessive la plus fréquente dans les populations caucasiennes. Elle est dûe à des mutations dans le gène CFTR qui code pour une protéine qui a une fonction canal chlorure et qui est exprimée au pôle apical des épithéliums sécrétoires. La mutation la plus fréquente F508del altère le repliement de la protéine, induisant sa dégradation précoce par le protéasome et son absence à la membrane plasmique. La recherche fondamentale se focalise sur la protéine mutée et cherche à découvrir des molécules capables d’adresser celle-ci au pôle apical des cellules épithéliales où elle pourra remplir sa fonction de canal chlorure. Au sein du laboratoire, nous nous intéressons aux interactions de la protéine CFTR/ F508del-CFTR avec d’autres protéines. Nous avons déjà montré l’existence d’une interaction non voulue entre F508del-CFTR et un filament intermédiaire, la cytokératine 8. En combinant une approche in-silico et du criblage haut débit, nous avons identifié des molécules capables d’interrompre ces interactions. Des tests fonctionnels sur des lignées cellulaires ainsi que sur des modèles murins ont montré une restauration de la fonction canal chlorure après traitements avec ces molécules. Au cours de ma thèse, je me suis intéressée à l’une d’entre elles qui est la molécule « c407 ». L’objectif de ma thèse était de comprendre les mécanismes d’action de cette molécule. J’ai également évalué l’efficacité des traitements actuels dans le contexte des allèles complexes de F508del-CFTR. Dans une seconde partie de ma thèse, j’ai étudié l’effet d’une cytokine (TNFα) sur la protéine mutée F508del-CFTR. De façon inattendue, j’ai observé que le TNFα, à des concentrations physiologiques, corrige le défaut de routage de la protéine F508del-CFTR. Cette observation pourrait expliquer une fonction résiduelle de la F508del-CFTR chez certains patients atteints de mucoviscidose. En conclusion, mes travaux ont permis de préciser les mécanismes d’action d’un correcteur et de découvrir un effet inattendu d’une cytokine pro-inflammatoire. Ces travaux permettent de relier la correction d’un défaut de routage au processus inflammatoire ouvrant ainsi un nouveau champ d’investigation.Cystic fibrosis is due to the loss of epithelial chloride transport caused by mutations in the CFTR gene, the most frequent mutation being F508del. One of the strategies developed to find new treatment for Cystic fibrosis (CF) is to discover compounds that correct the trafficking of F508del-CFTR to the plasma membrane. Using hypothesis-driven approach and combining modeling of NBD1, molecular docking and functional assays, we identified 4 compounds that correct F508del-CFTR function in cells (including human primary bronchial cells in culture) and F508del mice. New correctors probably act by interrupting the interaction between F508del-CFTR with keratin 8 (Odolczyk et al EMBO Mol Med 2013). During my PhD, I focused on one of those molecules, the "c407" molecule. The aim of my thesis was to investigate the mechanisms of action of this molecule. I have also evaluated the effectiveness of current treatments in the context of complex alleles F508del-CFTR. In the second part of my thesis, I studied the effect of a cytokine (TNFα) on the protein F508del-CFTR. Unexpectedly, I observed that the TNFα at physiological concentrations, corrects the trafficking of F508del-CFTR protein. This observation could explain a residual function of F508del-CFTR in some CF patients. In conclusion, my thesis helped to clarify the mechanisms of action of new correctors of F508del-CFTR
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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