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    Impact moléculaire et physiologique de la guêpe parasitoïde Cotesia congregata et de son polydnavirus sur l'insecte hôte Manduca sexta

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    Cotesia congregata est une guêpe parasitoïde qui se développe à l’intérieur de la larve du Lépidoptère, Manduca sexta. Ce parasitoïde a développé une stratégie de virulence qui utilise un symbionte viral de la famille des Polydnavirus nommé Cotesia congregata bracovirus. Mon travail de thèse a permis de caractériser le dialogue moléculaire au cours de l’interaction par des approches de transcriptomique à haut débit et de physiologie. Ces travaux ont permis d’établir la première carte fonctionnelle du génome viral et de visualiser l’ensemble des gènes de M. sexta régulés au cours du parasitisme. La régulation des gènes de l’immunité a révélé que le parasitisme n’empêche pas l’induction de peptides antimicrobiens, mais entraine la sous-expression de gènes impliqués dans la réponse cellulaire. De plus j’ai pu mettre en évidence une réduction du nombre de cellules adhérentes au cours de l’interaction et décrire l’induction d’un phénotype de type apoptose d’une catégorie de cellules immunitaires. Ces résultats permettent d’identifier des gènes acteurs de l’interaction et apportent de nouvelles connaissances relatives aux interactions hôtes-parasitoïdes.Cotesia congregata is a parasitoid wasp that develops inside the lepidopteran larvae, Manduca sexta. This parasitoid wasp has evolved virulence strategies using an obligate viral symbiont from the Polydnavirus family named Cotesia congregata bracovirus. My thesis work has allowed us to characterize the molecular dialogue during the interaction by physiological and highthroughput transcriptomic approaches. This work allowed to obtain the first functional map of the viral genome and to identify all M. sexta genes regulated during parasitism. Regulation of immune genes revealed that parasitism does not prevent induction of antimicrobial peptides, but leads to the downregulation of genes involved in the cellular response. Moreover, I was able to demonstrate a reduction in the number of adherent cells during the interaction and to describe this induction as an apoptosis-like phenotype targeting a specific population of immune cells. These findings open the way to the identification of candidate genes involved in this particular interaction and provide new insights into host-parasitoid interactions in general

    Molecular and physiological impact of the parasitoid wasp Cotesia congregata and its polydnavirus on the insect host Manduca sexta

    No full text
    Cotesia congregata est une guêpe parasitoïde qui se développe à l’intérieur de la larve du Lépidoptère, Manduca sexta. Ce parasitoïde a développé une stratégie de virulence qui utilise un symbionte viral de la famille des Polydnavirus nommé Cotesia congregata bracovirus. Mon travail de thèse a permis de caractériser le dialogue moléculaire au cours de l’interaction par des approches de transcriptomique à haut débit et de physiologie. Ces travaux ont permis d’établir la première carte fonctionnelle du génome viral et de visualiser l’ensemble des gènes de M. sexta régulés au cours du parasitisme. La régulation des gènes de l’immunité a révélé que le parasitisme n’empêche pas l’induction de peptides antimicrobiens, mais entraine la sous-expression de gènes impliqués dans la réponse cellulaire. De plus j’ai pu mettre en évidence une réduction du nombre de cellules adhérentes au cours de l’interaction et décrire l’induction d’un phénotype de type apoptose d’une catégorie de cellules immunitaires. Ces résultats permettent d’identifier des gènes acteurs de l’interaction et apportent de nouvelles connaissances relatives aux interactions hôtes-parasitoïdes.Cotesia congregata is a parasitoid wasp that develops inside the lepidopteran larvae, Manduca sexta. This parasitoid wasp has evolved virulence strategies using an obligate viral symbiont from the Polydnavirus family named Cotesia congregata bracovirus. My thesis work has allowed us to characterize the molecular dialogue during the interaction by physiological and high-throughput transcriptomic approaches. This work allowed to obtain the first functional map of the viral genome and to identify all M. sexta genes regulated during parasitism. Regulation of immune genes revealed that parasitism does not prevent induction of antimicrobial peptides, but leads to the down-regulation of genes involved in the cellular response. Moreover, I was able to demonstrate a reduction in the number of adherent cells during the interaction and to describe this induction as an apoptosis-like phenotype targeting a specific population of immune cells. These findings open the way to the identification of candidate genes involved in this particular interaction and provide new insights into host-parasitoid interactions in general

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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