1,721,247 research outputs found
Data review and new contribution to the parasites study of Roman period, and methodological input from the markers extraction to the treatment of results
No full textLes données paléoparasitologiques pour l’époque romaine sont nombreuses, mais souvent diluéesdans des rapports, des monographies ou des articles scientifiques. La première partie de ma thèsevise à rassembler ces informations, et présente une synthèse des données disponibles pour l'époqueromaine (27 av. - 476 ap. J.-C.). Dans cette perspective, une approche pathographique des maladiesparasitaires a été réalisée, et une liste des parasites connus dans l'Antiquité a pu être réalisée. Nousavons également complété ces données grâce à l’étude de onze nouveaux sites archéologiques.L’ensemble des résultats a été intégré dans une base de données, dont l'exploitation a permisd'étudier la répartition géographique des taxons, et de comparer leurs fréquences en fonction dedifférents paramètres tels les types de sites, d'activités, ou d'échantillon.Une seconde partie de mon travail s’est attaché à comparer et améliorer la technique employée pourl’extraction des oeufs de parasites anciens. Plusieurs tests ont été réalisés, qui montrent que lesméthodes sans sélection chimique permettent d’extraire un grand nombre de résidus tout enconservant le maximum de biodiversité. Enfin la quantification précise des oeufs lors des études dessites archéologiques du corpus a permis de tester des approches statistiques et de spatialisation dansle traitement des résultats. Ainsi, l'emploi d’outils tels la classification ascendante hiérarchique(CAH), les systèmes d'information géographique (SIG), ou la micromorphométrie sur les oeufs, ontpermis d'affiner les identifications, et les interprétations des structures au sein des sitesarchéologiques. Ces résultats montrent l’intérêt d’intégrer ces outils dans les étudespaléoparasitologiques à l’avenir.Paleoparasitological data concerning the Roman period are numerous, but scaterred in reports,monographs or scientific articles. The aim of the first part of my thesis is to collect theseinformations, and provide a review of available data for the Roman period (27 BC - 476 AD). Forthis purpose, a pathographic approach for parasitic diseases has been performed and a listing ofparasites known in Antiquity has been made. We have also completed the data with the study ofeleven new archeological sites. All results have been include in a database. The exploitation of dataallowed to study the taxa geographical repartition, and to compare their frequencies according tovarious parameters such as the type of sites, activities or samples.A second part of my work is focused on comparing and improving the method used to extractancient eggs. Several tests have been performed which point out that methods without chemicalselection allowed to extract many residues, while maintaining the maximum of biodiversity. Tofinish, the precise quantification of eggs during the study of archeological sites from the corpus,allowed to test statistical and spatialization approaches in the treatment of results. So, using toolssuch as hierarchical cluster analysis (HCA), geographic information system (GIS), ormicromorphometry on eggs, allowed to refine identifications and interpretations of structures withinarcheological sites. These results point out the interest to include in the future these tools inpaleoparasitological studies
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
Paleogenetics to study ancient gastrointestinal helminths
No full textLa paléoparasitologie est l’étude des restes de parasites préservés dans des échantillons archéologiques et permet de mieux comprendre l’état de santé des populations anciennes et d’obtenir des informations d’ordre anthropologique ou ethnologique, sur les régimes alimentaires ou les conditions d’hygiène au quotidien. Les restes de parasites peuvent être retrouvés sous forme de macro-restes (vers ou larves), d’antigènes, d’ADN ou d’œufs. Cesderniers peuvent être particulièrement bien préservés au cours du temps car ils sont composés en partie de chitine, les rendant résistants aux processus de dégradation. L’observation microscopique de leurs caractéristiques morphologiques et micrométriques permet d’identifier les taxons au niveau du genre ou de la famille. Dans le cadre de cette thèse, plusieurs helminthes gastro-intestinaux, dont les œufs sont fréquemment retrouvés dans des échantillons archéologiques, ont été ciblés par une approche génétique. Il s’agit des vers plats Tæniasaginata, T. solium, T. asiatica, Echinococcus granulosus, E. multilocularis, Diphyllobothriumlatum, D. dendriticum et D. nihonkaiense, des nématodes Trichuris trichiura, Enterobiusvermicularis et Ascaris sp. et des douves Fasciola hepatica, F. gigantica, Dicrocoeliumdendriticum et D. chinensis.La méthode « aMPlex Torrent » permet de détecter, dans un grand nombre d’échantillons archéologiques, une faible quantité d’ADN de parasites. Cette approche combine la spécificité et la sensibilité de la PCR au haut-débit du séquençage de nouvelle génération. Plusieurs vestiges, provenant de périodes et de régions géographiques diverses, ont été analysés. Des résultats génétiques ont été obtenus pour des échantillons aussi anciens que 7200 BP. Nous avons par ailleurs obtenus les premières séquences anciennes de Taenia sp., Diphyllobothriumsp., Echinococcus sp., et les premières séquences européennes d’Enterobius vermicularis. Auvu de ces résultats, notre approche apparait comme étant complémentaire à la microscopie.Palaeoparasitogy, the study of parasite remains from archaeological samples, is adiscipline that can highlight questions about the health status of the ancient populations. It can give important anthropological or ethnological information such as the diet and the hygiene conditions of past societies. The remains can be preserved as macroremains (worms or larvae),antigens, DNA or eggs. Because they are partially made of chitin, eggs of gastrointestinalhelminths resist well over time to the taphonomic degradation process. It is possible to distinguish between different families or genera of parasites by looking at the morphological features of eggs. However, since several taxa share common features, the determination is rarelypossible at the species level. For this thesis, several parasite species for which eggs arecommonly observed in archeological samples have been studied by a genetic approach. Westudied the tapeworms Tænia saginata, T. solium, T. asiatica, Echinococcus granulosus, E.multilocularis, Diphyllobothrium latum, D. dendriticum, and D. nihonkaiense; the nematodesTrichuris trichiura, Enterobius vermicularis, and Ascaris sp.; and the flukes Fasciola hepatica,F. gigantica, Dicrocoelium dendriticum, and D. chinensis.The “aMPlex Torrent” approach has been set up to detect minute amounts of DNA from parasites in multiple archaeological samples. This approach combines the specificity andsensitivity of PCR to the throughput of Next-Generation sequencing. Several samples have been analyzed by this approach. We obtained genetic results for samples as old as 7200 BP and from various geographical and archeological contexts. We obtained the first ancient DNA sequences for Taenia sp., Diphyllobothrium sp., Echinococcus sp. and the first European sequences forEnterobius vermicularis. Genetic analyses and microscopic observations appear to be complementary. Indeed, at least one taxon per sample was detected by one of the two approaches
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
Les parasites dans les lacs nord alpins au Néolithique (3900-2900 BC) et nouvelles données dans la détection des paléoantigènes de Protozoa.
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