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Information DigestionDias, Gaël 10 December 2010 (has links) (PDF)
The World Wide Web (WWW) is a huge information network within which searching for relevant quality contents remains an open question. The ambiguity of natural language is traditionally one of the main reasons, which prevents search engines from retrieving information according to users' needs. However, the globalized access to the WWW via Weblogs or social networks has highlighted new problems. Web documents tend to be subjective, they mainly refer to actual events to the detriment of past events and their ever growing number contributes to the well-known problem of information overload. In this thesis, we present our contributions to digest information in real-world heterogeneous text environments (i.e. the Web) thus leveraging users' efforts to encounter relevant quality information. However, most of the works related to Information Digestion deal with the English language fostered by freely available linguistic tools and resources, and as such, cannot be directly replicated for other languages. To overcome this drawback, two directions may be followed: on the one hand, building resources and tools for a given language, or on the other hand, proposing language-independent approaches. Within the context of this report, we will focus on presenting language-independent unsupervised methodologies to (1) extract implicit knowledge about the language and (2) understand the explicit information conveyed by real-world texts, thus allowing to reach Multilingual Information Digestion.
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Sensibilisation allergénique au cours des huit premières années de vie, facteurs et morbidité associés dans la cohorte de naissances PARIS / Allergic sensitization over the first eight years of life, associated factors and morbidity in PARIS birth cohortGabet, Stephan 02 October 2017 (has links)
Contexte. Les premières années de vie apparaissent particulièrement propices au développement de la sensibilisation allergénique. Objectifs. Cette thèse vise à : i) décrire les profils de sensibilisation allergénique chez le nourrisson et l’enfant, ii) étudier l’association entre ces profils et la morbidité allergique et iii) identifier les facteurs de risque de cette sensibilisation. Méthodes. Dans le cadre du suivi de la cohorte prospective de naissances en population générale Pollution and Asthma Risk: an Infant Study (PARIS), la sensibilisation allergénique a été évaluée chez 1 860 nourrissons à 18 mois et 1 007 enfants à 8/9 ans par dosage des IgE spécifiques dirigées contre 16 et 19 allergènes, respectivement. Les informations concernant la santé et le cadre de vie des enfants ont été recueillies par questionnaires standardisés répétés. Des profils de sensibilisation et des profils de morbidité ont été identifiés par classification non supervisée et mis en relation par régression logistique multinomiale. Enfin, les facteurs associés à la sensibilisation allergénique chez le nourrisson ont été étudiés par régression logistique multivariée. Résultats. Dès 18 mois, 13,8% des enfants étaient sensibilisés et 6,2%, multi-sensibilisés. À 8/9 ans, ces prévalences étaient de 34,5% et 19,8%, respectivement. Les profils de sensibilisation identifiés chez le nourrisson (3) et dans l’enfance (5) différaient au regard de la morbidité allergique. L’analyse étiologique a permis de préciser le rôle des expositions précoces aux allergènes et aux microorganismes sur la sensibilisation allergénique. Conclusion. Cette thèse contribue à une meilleure compréhension de l’histoire naturelle de la sensibilisation allergénique, et ce, dès les premières années de vie. Cette connaissance est essentielle à la prévention des maladies allergiques qui en découlent. / Background. The first years of life appear to be critical for the development of allergic sensitization. Objectives. This thesis aims: i) to describe allergic sensitization profiles in infants and children, ii) to assess the link between these sensitization profiles and allergic morbidity, and iii) to identify risk factors for allergic sensitization. Methods. This work concerns children involved in the Pollution and Asthma Risk: an Infant Study (PARIS) population-based prospective birth cohort. Allergic sensitization was assessed in 1,860 18-month-old infants and 1,007 8/9-year-old children by specific IgE measurements towards 16 and 19 allergens, respectively. Lifelong health and living condition data were collected by repeated standardized questionnaires. Sensitization profiles and morbidity profiles were identified using unsupervised classification, and related to each other by multinomial logistic regression. Finally, risk factors for early allergic sensitization were assessed by multivariate logistic regression. Results. As soon as 18 months of age, 13.8% of children were sensitized and 6.2%, multi-sensitized. When 8/9 years old, corresponding prevalence was 34.5% and 19.8%, respectively. Sensitization profiles identified in infancy (3) and in childhood (5) differed in terms of allergic morbidity. Risk factor analysis allowed to clarify the role of early exposure to allergens and microorganisms on allergic sensitization. Conclusion. This thesis improves the natural history of allergic sensitization understanding, as soon as the first years of life. This knowledge is essential for subsequent disease preventing.
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