Tesis sobre el tema "Expositions humaines"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte los 50 mejores tesis para su investigación sobre el tema "Expositions humaines".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.
Huot, Delphine. "Impact sanitaire du dioxyde d'azote : bilan des expositions humaines contrôlées". Paris 5, 1997. http://www.theses.fr/1997PA05P209.
Texto completoChoueiri, Joanna. "Évaluation des expositions humaines aux polluants de l'environnement par l'alimentation". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALS005.
Texto completoThe main challenges related to nutrition include ensuring an optimal diet, ensuring a good environmental impact of the food system, and ensuring food safety for consumers, including exposure to chemicals, especially since food is a major source of exposure to environmental pollutants for the general population. Consequently, this thesis embarks on a comprehensive analysis to address these challenges at the following levels: To meet the environmental and food safety challenges, through the development and implementation of a methodology to assess the impact of organic food consumption versus conventional food on consumer exposure to environmental pollutants in Europe, and to meet the challenge of ensuring an optimal diet for all, through the assessment of the nutritional quality of University Grenoble Alpes (UGA) students via a score based on the national nutrition program in France (PNNS) while studying the impact of food insecurity on adherence to national dietary recommendations. To achieve these objectives, a comprehensive database was first created to collect data from the literature on contamination levels in organic agriculture in Europe, as no exhaustive databases exist in the literature. Then, since the data from the database had limitations (quantitative and unit limitations) that prevented the direct calculation of exposure levels from the available data, an Excess Ratio (ER) approach was developed that first allowed the evaluation of the chemical content between different agricultural foods and served as the basis for the methodology to assess the impact of organic food consumption on the level of exposure to chemicals compared to conventional foods. Further, a population of UGA students was selected and assessed using a score developed based on the PNNS, and the association between food insecurity and adherence to the PNNS was examined. The dietary exposure profile of the students was assessed using the French Total Diet Study (EAT2) contamination database for selected substances and the developed methodology for assessing the impact of organic food consumption was applied to this population. As the students showed a level of concern for dimethoate, cadmium, lead, inorganic arsenic, nickel and dioxins, the impact of organic food consumption on the level of exposure to these substances was inconclusive. In terms of dietary quality, the overall compliance rate with the PNNS guidelines was 62%, with food insecure students showing lower compliance for fruits and vegetables (p = 0.004), alcohol (p = 0.005) and higher compliance for meat, poultry, and eggs (p = 0.021) and whole grains (p = 0.01). This thesis has provided a method that is universal and overcomes all the limitations of the currently available data, allowing the evaluation of the effect of organic food consumption. This thesis also serves as an illustrative example of a multifaceted research that addresses numerous challenges related to dietary practices
Cortejade, Aurélie. "Approches et outils pour l’évaluation de l’Exposome : du dosage de contaminants vers le screening non ciblé pour la caractérisation des expositions humaines environnementales". Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10219/document.
Texto completoThese research works highlight the development of analytical methods, based on mass spectrometry, to assess the Exposome according to different strategies. A selective multiresidue method for the analysis of plastic additives and their degradation products that may be released by plastic packaging in food and beverages and thus ingested by man was developed. This method consists of a Stir Bar Sorptive Extraction with bars covered by polydimethylsiloxane derivatives, followed by an analysis by liquid chromatography coupled to tandem mass spectrometry with a triple quadrupole instrument. To detect and quantify a wide range of contaminants in contact with man in daily routine, a screening method was developed by liquid chromatography coupled to high resolution mass spectrometry with a quadrupole-time-of-flight instrument from urinary matrix. The targeted screening method validated according to FDA guidelines allows the quantification of contaminants classified according to different families, in urine without sample preparation, at concentrations of the order of ng.mL-1. This method was applied to volunteers’ urine samples. The non-targeted screening method allows issuing numerous assumptions of compound identification after MS/MS fragmentation. The implementation of this tool to measure the Exposome associated with statistical studies, contribute greatly to the understanding of the causal relationships between diseases and environmental factors
Andujar, Pascal. "Altérations génétiques des tumeurs respiratoires humaines et murines après exposition à des fibres minérales". Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0030.
Texto completoRésumé en anglais non communiqué
Mayaguezz, Henky. "Exposition humaine, analyse et renforcement des capacités d’évacuation face aux tsunamis à Padang (Indonésie)". Thesis, La Rochelle, 2015. http://www.theses.fr/2015LAROS020/document.
Texto completoThis dissertation summarizes an integrated approach whose aim is to assess the human exposure and its spatial and temporal variations in the event of a tsunami in a costal urban zone of Indonesia, as well as the capacity to join evacuation shelters for populations under threat. This research systematizes methods to estimate the amount of people present hour by hour during any day of the week and the year, at a very fine scale, in an urban area. It uses a hypothesis about a common rhythm of life which controls the activities and therefore the distribution of the Padang inhabitants. Considering that time of a tsunami occurrence is impossible to estimate, this information is very important to improve risk reduction programs. This approach allows in particular identifying various types of scenarios for the distribution of the population that can then be used to evaluate the evacuation capacity of these populations. A dynamic simulation model resulting from this research allows for the measurement of the accessibility of shelters following these scenarios. The analysis of the results suggests improvements for a better preparation on the part of authorities to protect civilians
Liamin, Marie. "Exposition in vitro de lymphocytes T humains aux hydrocarbures aromatiques polycycliques : étude des effets immunotoxiques". Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B060/document.
Texto completoPolycyclic aromatic hydrocarbons (PAHs), such as benzo(a)pyrene (B[a]P), are ubiquitous environmental contaminants generated during organic matter combustion. These compounds have been associated with the development of toxic effects on human health, including carcinogenic and immunotoxic effects, mainly related to Aryl hydrocarbon Receptor (AhR) activation. Among the immune system cells, T lymphocytes appear as major targets of PAHs. Previous results, obtained in the laboratory, have shown that activation of primary human T lymphocytes leads to a functional AhR expression increase, suggesting their ability to respond to PAH exposure. Our specific aims are: (1) to determine the effects of B[a]P on gene expression profiles in human normal lymphocytes by using large-scale approaches such as microarray-based transcriptome analysis, (2) to monitor the genotoxic and immunotoxic effects of B[a]P by measuring DNA damage and immunosuppressive actions, respectively and, (3) to analyze the modulation of these effects by the presence of other PAHs. Our work propose primary cultures of activated human T lymphocytes as a good model for studying both genotoxic and immunotoxic effects of environmental contaminants such as PAHs and predicting human health issues. It also gains a comprehensive insight into the immune response regulation after PAH exposure and provides potential new biomarkers of exposure to these environmental contaminants
Rolland, Pauline. "Décontamination du cuir chevelu humain après exposition aux agents chimiques de guerre". Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10215.
Texto completoOrganophosphorous nerve agents are designed as chemical warfare agent because they represent a threat both for the military and the civilians. Due to its low volatility, VX mainly remains in its liquid form and mostly presents a contamination by skin contact. Decontamination of exposed body surface is therefore crucial to prevent victims' poisoning. In case of terrorist acts, civilian human scalp could be a preferential site of exposure. This body region, rich in hair follicles, may require adapted decontamination products and procedures. The aims of this work are: 1) Validation of a relevant in vitro human scalp skin model; 2) Determination of decontamination strategies; 3) Formulation of new decontamination systems; 4) Evaluation of their decontamination efficacy. Pig ear skin is a relevant model when studying the in vitro percutaneous penetration of VX through human scalp. Pig skull roof skin could be used when studying the affinity of VX for hair. This study has shown that most of the nerve agent remains on the skin surface up to 2h of exposure, which means that it is worth decontaminating even if contamination occurred 2h before. Microemulsions loading a detoxifying agent (oxime) are the most efficient systems because they are able to penetrate deeper into the skin to neutralize the agent in situ. Adsorbing powders and Pickering emulsions could interact with the agent present on the skin surface and in the superficial layers. Our results from the in vitro experiments have demonstrated that these formulations are more efficient than Fuller's earth for skin decontamination after 45 min of VX exposure
Peltier, Lucas. "Impact d’une exposition au fer sur l’axe S1P/S1PR dans la lignée ostéoblastique humaine MG-63". Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B059/document.
Texto completoOsteoporosis may complicate genetic or secondary iron overload as reported in clinical and animal studies. However, the mechanisms leading to disrupted bone homeostasis are still to be fully elucidated. In vitro, iron exposure of both osteoblast and osteoclast cell models induces phenotypic and functional impairment, but the molecular mechanisms of iron excess on bone cell physiology are not well characterized, particularly in osteoblast. Our objective was to study the impact of iron overload on osteoblast biology and characterize the molecular mechanisms involved. Transcriptomic analysis previously performed by our group on MG-63 osteoblast-like cell-line to identify iron-modulated genes revealed that expression of SPNS2 gene, which encodes a transporter for the signaling lipid sphingosine 1-phosphate (S1P), is potentially induced by iron. The purpose of this work was to characterize the SPNS2 iron-related regulation and analyze its potential impact on S1P efflux and the S1P/S1PR signaling pathway in MG-63 cells. Our findings showed that iron exposure induces a dose-dependent increase of SPNS2 mRNA levels in MG-63 osteoblast-like cells that was not observed in hepatocyte and enterocyte cell models. We then performed a fluxomic assay on MG-63 cells to investigate iron potential impact on S1P efflux. Unexpectedly, our data showed that extracellular S1P levels were decreased in presence of iron excess and its associated SPNS2 upregulation. Furthermore, based on the observed iron associated S1PR1 and COL1A1 decrease, the defect in S1P export system seems to have functional consequence on MG-63 cells. These results suggest that iron may affect osteoblast S1P/SPR signaling and potentially alter a wide range of bone processes, thus participating in bone impairment in situations of chronic iron overload. These data open a new door for the understanding of mechanisms involved in iron-induced osteoporosis
Jossé, Rozenn. "Recherche de gènes cibles de contaminants de l'environnement génotoxiques après exposition aiguë ou répétée des cellules hépatiques humaines HepaRG". Rennes 1, 2010. http://www.theses.fr/2010REN1B079.
Texto completoThe lack of relevant in vitro models makes it challenging prediction of toxicity of chemicals in humans, particularly effects induced by reiterated exposure to low concentrations and mixtures. The present work aimed at determining whether human hepatoma HepaRG cells, which are able to metabolize chemicals to levels close to those found in primary human hepatocytes, could bring answers to these challenges. We first showed that these cells maintained their functional capacity for at least one month after differentiation and were suitable for the detection of DNA damage induced by promutagens using the comet and the cytokinesis-block micronucleus assays. Then, we have studied mechanisms involved in AFB1 toxicity and identified FHIT tumor suppressor gene as a potent early biomarker for discriminating between genotoxic and nongenotoxic compounds
Salomon, Jérôme. "Modification de l'usage antibiotique en population humaine et résistances bactériennes". Paris 6, 2008. http://www.theses.fr/2008PA066662.
Texto completoSedru, Marianne. "Etude de l’impact d’une exposition chronique au paraquat dans un modèle de Drosophile exprimant l’alpha-synucléine humaine". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN083.
Texto completoParkinson's disease (PD) is mainly characterized by the aggregation of α-synuclein (α-syn) into Lewy bodies and the selective degeneration of dopaminergic neurons associated with locomotor defects. The etiology of PD is still incomplete, but its multifactorial origins involve genetic and environmental stress factors. The characterization of animal models expressing human α-syn exposed to pesticides is essential for the identification of the mechanisms underlying the aggregation of α-syn upon chemical exposure. In this study, our goal was to characterize the effects of chronic paraquat (PQ) exposure on Drosophila expressing the WT or mutated [A53T] form of α-syn in all neurons.We showed that the expression of α-syn [A53T] increased the sensitivity to chronic exposure to PQ. In addition, PQ induced α-syn accumulation, especially the pathological form, phosphorylated on serine 129. We also found autophagic vacuoles associated with Ref(2)-P/p62 protein accumulation suggesting an impaired autophagic flux in Drosophila expressing α-syn [A53T] under chronic PQ exposure.By taking into account the genetic and environmental aspects, our approach will allow to identify the main factors responsible for the development of PD in the sporadic cases that represent nearly 90% of patients. Further studies based on this model will allow to explore potential therapies for PD treatment
Tenailleau, Quentin. "Multi-exposition en milieu urbain : approche multi-echelle de l'exposition humaine au bruit et à la pollution atmosphérique". Thesis, Besançon, 2014. http://www.theses.fr/2014BESA2052/document.
Texto completoEvery day, 15% of the European population is exposed to average noise or air pollution levels exceeding theEuropean legal threshold. Levels and distribution of each pollutant across the city depend of individual sourcesemissions, dispersion phenomenon, and urban environment. Consequently, spatial variability of multi-exposure levelremains mostly unknown. The aim of this Ph. D. thesis is to identify and describe multi-exposure situations in the cityof Besançon. Environmental noise levels, and concentrations of several air pollutants (NO2, benzene, PM10 and PM2.5),have been modeled using a fine scale grid (2m x 2m). Model compatibility has been maximized by the use of commoninput into the calculation software Mithra-SIG (for noise) and COPERT4/ADMS-urban (for air pollutants). In a firsttime, impact of the neighborhood definition on exposure levels has been explored for both pollutions. Twelveindicators, each representing a different definition of the exposure area in the dwelling vicinity, have been used toquantify exposure levels around the 10 865 inhabitable building of Besançon. Obtained results show a significantimpact of the neighborhood definition on the exposure levels. Different neighborhood definitions lead to a differentialbias caused by a different accounting for environmental variables. This bias exists for all studied pollutant, but indifferent proportion depending on the pollutant. In a second time, situations of multi-exposure to noise and NO2 havebeen identified in the city. Results indicate a complex relation between pollutants and allow the description of severalmulti-exposure situations across the city. This work constitute one of the firsts approaches of this kind in France andallow a better understanding of the existing relations between neighborhood, exposure area, environmental parametersand exposure levels
Dufour, Diane. "Implication du système sérotoninergique dans l'autisme : étude de marqueurs centraux (modèle animal) et périphériques (plaquette sanguine humaine)". Thesis, Tours, 2011. http://www.theses.fr/2011TOUR3801/document.
Texto completoDevelopment of markers of pathogenesis for autism would improve understanding of the pathophysiology, would complete clinical arguments for diagnosis and would propose preventive or therapeutic research pathways. Our hypothesis is that modifications to the serotonergic system may be potential markers for autism. To test this hypothesis, we used two study models : the human blood platelet and an animal model, rats prenatally exposed to valproic acid. We have shown that: - platelet serotonin levels and serotonin transporters density may be jointly tested in humans. These parameters do not significantly differ between groups of controls, patients with autism and first-degree related, - serotonin levels were decreased by 46% in the hippocampus of rats exposed to valproic acid, and no significant modification was observed in serotonin transporters density. These results reinforce the interest of central explorations.These studies reinforce the interest of central exploration of serotonergic potential markers in patient with autism and especially with molecular imaging tools
Laborie, Stéphanie. "Exposition humaine aux perturbateurs endocriniens par inhalation : caractérisation de la contamination de l’air intérieur par analyses chimiques et biologiques in vitro". Thesis, Paris, EPHE, 2015. http://www.theses.fr/2015EPHE3059/document.
Texto completoThe objective of this project was to develop a bio-analytical approach leading to the assessment of the inherent hazard of the indoor air multi-contamination. Chromatographic methods combined with mass spectrometry were developed and validated for 62 target molecules known or suspected as endocrine-disrupting (ED) compounds. The ED potential was assessed by cellular bioassays measuring perturbations of transcriptional activity. The data showed that the predominant families of compounds in indoor air were in the following descendant order: phthalates > musks > alkylphenols > parabens. The ED contaminants were mainly present in gaseous phase, and the most contaminated locations were the day nursery and the house. An estrogenic, thyroid and anti-androgenic potential was attributed to indoor air. In agreement with its contamination profile, the biological activity of the latter was concentrated predominantly in the gaseous phase, and tended to be higher in the day nursery and the house. An effect-directed analysis (EDA) was carried out to identify the target chemicals responsible for the ED effects of indoor air. The following chemicals were identified as being potentially responsible for the observed ED effects: phthalates, methyl-paraben, alkylphenols, cypermethrin and synthetic musks. This work provides both knowledge about the inherent hazard of the indoor air multi-contamination and exposure data useful in health risk assessment
Goldman, Noémie. "Un Monde pour les XX: Octave Maus et le groupe des XX :analyse d'un cercle artistique dans une perspective sociale, économique et politique". Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209691.
Texto completoNous avons ainsi voulu replacer le groupe des XX dans son contexte économique, politique et social. La diversification des approches et des sources était donc un aspect essentiel de nos recherches. Plusieurs voies d’approche ont été empruntées, telles que l’histoire culturelle, la sociologie de l’art, l’histoire du marché de l’art, l’analyse politique ainsi que l’étude de la visual culture.
Dans un premier temps, nous analysons l’émergence de la nouvelle scène artistique construite autour du groupe des XX. Nous débutons par une analyse plus monographique du parcours de Maus afin de définir les qualités essentielles de l’animateur d’art qu’il incarne, ainsi que son rôle dans la reconfiguration du milieu culturel. Ensuite, notre étude se concentre sur la mobilisation d’un public autour des salons et la mise en place d’un nouveau marché de l’art aux XX.
Dans un second temps, notre étude se penche sur les œuvres créées par les XX et sélectionnées par le public d’amateurs fidèles au groupe. Nous éclairons cette production artistique en y décelant les influences des questionnements et des prises de position sociales et politiques du public des XX, défini précédemment. L’analyse iconographique et stylistique des œuvres s’accompagne d’un travail sur ce milieu culturel, et particulièrement sur ses positions face aux débats sociaux de l’époque. Cette étude aboutit, d’une part, à une description approfondie du public des XX, et, d’autre part, à une meilleure compréhension de l’originalité de la production esthétique des artistes du groupe. /
This PhD thesis concentrates on the mechanisms by which the artistic world in Brussels was reorganized at the end of the 19th century. The research focuses on the places, institutions, publics, art markets and aesthetic developments that characterized the new artistic scene constructed around the “Salon des XX”. The purpose of this study is to demonstrate that this artistic circle, led by Octave Maus, produced an art influenced by social, political and economic issues. Another aim has been to analyze the public that defended the artists by studying its social, cultural and generational nature.
This thesis, which is divided into two parts, for the first time explores the circle of the XX in its economic, political and social environment. The diversification of sources and scientific methods was therefore an essential aspect of the research. Different methods were applied such as, for example, the cultural history, the sociology of art, the history of the art market, political sciences and the visual culture.
The first part of this study is about the emergence of a new artistic scene founded around the “Groupe des XX”. The first objective was to investigate the personal and professional path followed by Octave Maus, the manager of the XX, who played a major role in the evolution of the cultural world. Subsequently the research focuses on the mobilization of a particular public and the creation of a new art market around the XX’s exhibitions.
The second part of this thesis considers the works of art created by the artists of the “Groupe des XX” and chosen by the public for private collections. New light is shed on this artistic production by the study of the social and political position of the XX’s public, considered as a social group. Hence the iconographic and stylistic analysis of the works goes together with a study of the XX’s milieu, and in particular with its political action. The present thesis, and the method that aims to study the works in parallel with the public’s social nature, lead to a better understanding of the cultural milieu and, at the same time, of the originality of the XX’s artistic creation.
Doctorat en Histoire, art et archéologie
info:eu-repo/semantics/nonPublished
Cordonnier, Sarah. "L' exposition des savoirs dans l'art contemporain : les formes de mobilisation des sciences humaines dans l'institution de l'art contemporain comme champ et comme formation discursive". Lyon, Ecole normale supérieure, 2007. http://www.theses.fr/2007ENSF0040.
Texto completoThis research aims to understand how the field of contemporary art autonomizing and institutionalizing mobilises knowledge (categories, proposals, devices) developed in an other area, that of humanities. The central issue of the thesis concerns the conditions of reception, representation and use of this knowledge. In order to analyze the forms of its appropriation, an empirical material has been established in various ways: it mainly consists of a series of artists’ biographies, in-situ observation in an art centre, compilation and quantitative processing of databases, a corpus of discourses produced in and out art institutions and texts having circulated at ten exhibitions. The content analysis of this later corpus allows the description of a presence and regular representations of Human Sciences (concepts, authors, subjects…), which testify that the mobilization of exogenous speech is underpinned by collective criteria. A characterisation of the institutional and enunciative practices of contemporary art exhibition had been made beforehand, in order to build and contextualize this corpus. Thus, the exhibitions can be located in a discursive space made of common rules and references, but also in a social space (depending on the trajectory and recognition of artists and institutions). Beyond the mere description, this approach allows the analysis of different types of use of the humanities, more or less rhetorical, legitimizing, rigorous; the variations in uses depend particularly on the purpose of the exhibitions, which can be mainly aimed to “audience” or to “the artists”
Audet, Marie-Claude. "Anomalies émotionnelles et motivationnelles consécutives à une exposition sous-chronique répétée à la phencyclidine chez le rat : analogies avec la schizophrénie humaine". Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24955/24955.pdf.
Texto completoRaffy, Gaëlle. "Exposition humaine aux composés organiques semi-volatils (COSV) en environnement intérieur par ingestion de poussières : évaluation de la bioaccessibilité orale des COSV". Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B053.
Texto completoThe quality of indoor environments is now a major public health concern. People spend nearly 90% of their time indoors where they are exposed to pollutants such as semi-volatile organic compounds (SVOCs) suspected of adverse health effects. Dust ingestion is a significant route of exposure to some of these SVOCs, especially for children. To characterize this exposure, it is necessary to consider the oral bioaccessibility of SVOCs, defined as the fraction of pollutant released into the gastrointestinal tract and available for absorption. In this context, the objectives of this PhD thesis are to (i) develop and validate a simple method for measuring the oral bioaccessibility of SVOCs in indoor dust and (ii) produce bioaccessibility data for SVOCs of health interest This article-based thesis consists of three chapters: a scientific context, which presents the sources and toxicity of SVOCs, then describes their presence in school air and dust, before addressing the different routes of human exposure; a state of the art on the oral bioaccessibility of SVOCs in dust; and the proposal of a simplified method for measuring this bioaccessibility, its validation, and its application to first samples. This work concludes on a broader context than ingestion by establishing perspectives that also consider inhalation and dermal bioaccessibility, in order to characterize the overall exposure to COSV in indoor environments
Malavaud, Sandra. "Exposition professionnelle, moyens de prevention et attitudes vis-a-vis des patients infectes par les virus de l'hepatite b et de l'immunodeficience humaine : une enquete parmi le personnel hospitalier du chu de toulouse (1988)". Toulouse 3, 1988. http://www.theses.fr/1988TOU31509.
Texto completoHyvelin, Jean-Marc. "Exposition ex vivo aux polluants gazeux des voies aériennes et des vaisseaux pulmonaires humains et animaux : effet sur la réactivité et la signalisation cellulaire". Bordeaux 2, 2000. http://www.theses.fr/2000BOR28714.
Texto completoLeblanc, Claire. "Des arts décoratifs aux arts industriels: contribution à la genèse de l'Art Nouveau en Belgique, 1830-1893". Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211045.
Texto completoThèse réalisée sous la direction de M. Michel Draguet et présentée en vue de l’obtention du titre de Docteur en Histoire de l’Art.
Bruxelles, janvier 2005.
Dès la fin du XVIIIe puis tout au long du XIXe siècle, le secteur décoratif connaît une mutation profonde sous l’impulsion de la Révolution industrielle. La production décorative, jusqu’alors issue d’un artisanat de longue tradition, se développe désormais également dans le registre industriel (production et diffusion à grande échelle). Cette nouvelle situation est la source d’un renouvellement important quant à la nature des disciplines décoratives, aux missions qui leur sont assignées ainsi qu’à l’organisation générale du secteur.
L’étude présentée sous le titre susmentionné vise à observer l’impact de ce bouleversement sur le secteur industriel belge durant le XIXe siècle, depuis la fondation du pays en 1830 jusqu’au moment d’éclosion de l’Art Nouveau en 1893, amorçant une nouvelle phase d’évolution du secteur.
Notre étude vise dès lors à établir une nouvelle lecture de l’évolution décorative belge de cette période. Au-delà des manifestations stylistiques, majoritairement passéistes tout au long du siècle, le secteur connaît une mutation profonde s’opérant autour de nombreuses interrogations quant à ses nouvelles orientations et ses nouveaux objectifs. La question de l’équilibre délicat entre la nouvelle nature industrielle et le caractère artistique de la production décorative en constitue le point central. Nous décelons deux phases clefs dans l’évolution de cette problématique. Dans un premier temps (durant la première moitié du XIXe siècle) deux catégories distinctes – l’une nouvelle, l’autre ancienne – cohabitent désormais au sein du seul secteur décoratif :d’une part un « art industriel » moderne aux missions sociales, d’autre part un « art décoratif » traditionnel et généralement luxueux. Si les objets produits dans les deux registres répondent communément à une destination utilitaire, leur rapport au « Beau » s’oppose. Dans un deuxième temps (durant la seconde moitié du XIXe siècle) – et suite à l’Exposition universelle de Londres de 1851 qui mettra à jour les limites de la situation développée durant la première moitié du siècle –, la majorité des acteurs du secteur ambitionneront la dissolution de cette dichotomie par la fusion de ces deux registres. L’alliance de l’art et de l’industrie constituera effectivement l’objectif principal d’une large partie du secteur décoratif belge de l’époque. Deux chantiers principaux viseront à l’accomplissement de cet objectif :d’une part, la réforme de l’enseignement décoratif et d’autre part, la création d’un musée d’arts décoratifs et industriels.
Ce cheminement révélera, simultanément, la nécessité d’une réforme stylistique. Celle-ci est alors conçue comme un aboutissement des deux principaux chantiers…….
Doctorat en philosophie et lettres, Orientation histoire de l'art et archéologie
info:eu-repo/semantics/nonPublished
Dargnat, Cendrine. "Sources, transfert et devenir des phtalates sur le bassin versant de la Seine : caractérisation des dangers pour l'environnement et les écosystèmes". Paris 6, 2008. http://www.theses.fr/2008PA066574.
Texto completoPons, Romain. "Etude sur les déterminants professionnels agricoles et leurs effets sur la reproduction et le développement de l'enfant". Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC430/document.
Texto completoAgricultural exposures, including pesticide exposure, have been associated with several negative effects on fertility, pregnancy and child development. Few studies focused on specific agricultural activity excepted floriculture and working in greenhouse and none was conducted in France. (1) More than 800 women, enroled in the AGRIculture & CANcer (AGRICAN) cohort and who reported a pregnancy since enrolment (2005) agreed to fill in 2 questionnaires. An increase of time to pregnancy was observed for women who worked on a farm, for those exposed to night work and to vibrations. Increased risks of spontaneous abortions or abnormalities were also observed in relation to agricultural work but these results need to be confirmed. (2) Multi-residue analytical method was developed and applied to women of childbearing age, working in crop-livestock farms. Twenty-five pesticides or metabolites were detected among 116 measured in urine samples. Herbicides were the most frequently detected, especially when women worked on corn-crop farms or were involved in breeding tasks. Glyphosate or its metabolite AMPA were detected in 85% of urine samples.Future project will allow us to investigate cognitive development of children born since 2005
Al, Zallouha Margueritta. "Étude prospective pilote des effets d'une exposition ex vivo de lymphocytes T humains à la pollution atmosphérique particulaire : recherche de biomarqueurs et influence de l'âge". Thesis, Littoral, 2017. http://www.theses.fr/2017DUNK0472/document.
Texto completoAtmospheric fine particulate matter (FP) are able to enter the lungs where some compounds can interact with lung cells and reach the bloodstream . Exposure to FP affects in particular susceptible populations such as the elderly. This thesis is part of a project aiming to identify the effects of FP on human T lymphocytes (LT) while attempting to determine biomarkers related to exposure and to evaluate the variation of the cellular response as a function of age. LT were isolated from blood samples of 91 volunteers belonging to three age groups (20-30, 45-55, 70-85 years) then exposed ex vivo for 72h to 45 µg/µl of FP collected in Dunkirk. The steps of isolation, purification and activation of LT were first optimized. Following the characterization of the sampled population, a homogeneous study population was selected (10 subjects/age class). We have demonstrated an induction of the genes coding for the enzymes involved in the metabolic activation of PAH identified in the PF sample. Characterization of the LT profile made it possible to propose a mixed th1/th2 profile cause by the exposure. Teh transcriptomic study of miRNAs revealed an overexpression of miR-124-3p involved in the regulation of several functions in the immune system and miR-1290 involved in several types of cancer. As for the influence of age, overexpression of the genes coding for the antioxidant enzymes (NQO1 and HMOX1), an increase in the concentration of cytokines (IL-4 and IL-13) as well as a modification of the expression profile of some miRNAs were noted on the elderly
Feugier, Patrick. "Étude pour le développement de l'endothélialisation des prothèses vasculaires : adaptation dynamique de fibroblastes et de cellules endothétiales humaines ensemencées sur des biomatériaux vasculaires, après exposition à des forces rhéologiques physiologiques". Lyon 1, 2003. http://www.theses.fr/2003LYO1T239.
Texto completoLesné, Laurianne. "Antiépileptiques et antalgiques pendant la grossesse et homéostasie du testicule foetal humain". Electronic Thesis or Diss., Université de Rennes (2023-....), 2023. http://www.theses.fr/2023URENB075.
Texto completoFetal development is a period that is particularly vulnerable to imbalances in the environment in which it takes place. The fetal testis plays a crucial role in the masculinization of the reproductive organs via its endocrine function, and any alteration can give rise to a range of malformations that can have an impact on a man's future fertility. During development, the embryo and then the fetus are exposed to a complex chemical environment known as the maternal exposome. Among the families of substances that make up the exposome are the medicines that pregnant women take to treat a chronic pathology or acutely to treat a pregnancy-related symptom. We are interested in two classes of drugs: anti-epileptics (AEs) on the one hand, and analgesics on the other, because epidemiological studies have reported an increased risk of hypospadias in newborns exposed in utero to valproic acid, an AE, and of malformations of the reproductive system in those exposed to paracetamol and ibuprofen in particular. The occurrence of these alterations could be linked to disturbances in hormonal balance. We used an organotypic culture model of human fetal testicular explants to compare the disruption profiles generated by a short exposure - 3 days - to analgesics and a short and long exposure - 28 days - to AEs. To do this, we adapted and optimized our model to approximate the chronicity of treatment in vivo. These studies, using organotypic cultures of human fetal testes, showed that three AEs could, over a more or less long period, induce an alteration in the endocrine function of this organ, leaving open the possibility that with chronic treatment, the androgenic impregnation of the fetus could be affected, and that this could have consequences for the target organs. Although the NSAID analgesics studied appear to have less spectacular effects on the endocrine function of the developing human fetal testis, their use during pregnancy continues to present a risk for other organs whose development is sensitive to or dependent on prostaglandins
Després, Christine. "Effets neuromoteurs d'une exposition environnementale au mercure, aux biphényls polychlorés et au plomb chez des enfants Inuit /". Montréal : Université du Québec à Montréal, 2005. http://accesbib.uqam.ca/cgi-bin/bduqam/transit.pl?&noMan=24174054.
Texto completoGirard, Max. ""La Grande Emotion". La mise en scène des missions chrétiennes dans les expositions coloniales et universelles : France - Belgique. 1897 - 1958". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE3010.
Texto completoFrance and Belgium organised several international and colonial exhibitions, as well as universal exhibitions or World Fairs, from the end of the 20th century to 1958. Through these world exhibitions, these two great colonial powers developed various forms of propaganda to account for their “civilizing missions”. Protestant and catholic missionaries took part in those great celebrations. By reading and working on archives of religious congregations such as the congregation of the Holy Spirit, The Jesuit, and the oeuvre de la Propagation de la Foi, but also the French, Belgian and Swedish national archives and the Holy Sea archives, I was able to understand how the missionaries organized themselves to take part in those exhibitions in France and Belgium. The missionaries organised exhibitions in ever growing pavilions which would become huge architectural complexes, from the 1897 exhibition (taking place in Tervuren) to the 1935 and 1958 exhibitions (taking place in Brussels), not forgetting the 1900, 1931 and 1937 Paris exhibitions. The way missionaries staged their work changed and evolved. Indeed, “indigenous” artifacts were gradually less displayed and missionaries used dioramas, stylish statistics and lit-up maps instead. The architecture of the pavilion was in itself telling, a good example of this being the 1931 pavilion of the Catholic missions. The way missionaries staged their exhibitions reflected the changes in their worldview. The colonized populations and their cultures were more and more emphasized, while the link with the colonization was less and less asserted and straightforward
Scorretti, Riccardo. "Caractérisation numérique et expérimentale du champ magnétique B. F. Généré par des systèmes électrotechniques en vue de la modélisation des courants induits dans le corps humain". Ecully, Ecole centrale de Lyon, 2003. http://bibli.ec-lyon.fr/exl-doc/rscorret.pdf.
Texto completoThis work is devoted to the developpement of models and numerical tools, to simulate the induced phenomena inside the human body, within the frequency range 50Hz-100KHz. Two main problems have to be solved : find the spatial distribution of a magnetic field generated by a power system (stray fields) ; compute the currents, which are induced by these stray fields inside the human body. Field radiated by a known system : classical numerical methods are not well adapted to this problem (they are too expansive) : we present a 3D model, which takes into account only the "essentials" of the system. Field radiated by an unknown system : we have developed several models of equivalent source, basing upon the concept of multipole. The parameters of these models are fitted from some local measurements of the flux density. Finally, we have developed a special formulation using finite elements, in order to compute the induced current density inside the human body
Bertran, Rojo Marc. "Correr entre los escombros - Courir entre les débris. La mobilité individuelle en période de crise sismique : facteur d'exposition humaine dans le cas du séisme de Lorca (Espagne 2011)". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU040/document.
Texto completoMay the eleventh, 2011, a double earthquake struck the town of Lorca in southeastern Spain. The earthquake had serious consequences for the population and caused extensive damage to buildings in the town. Earthquakes are phenomena characterized by their relatively low frequency and their violence. In the Mediterranean Basin, most earthquakes are only perceptible using measuring instruments. Recent seismic events have surprised the scientific community by their moderate magnitude associated with a high intensity. This is particularly the case of Lorca's earthquake. In the last 40 years, the Spanish authorities have tried to develop prevention towards seismic phenomenon. Measures have been taken by improving seismic building codes or by updating the seismic zoning, each revision taking into account wider zones at risk. In general, events give rhythm to the evolution of these measures. However, variables like the location of cities in seismic zones and the vulnerability of existing buildings can hardly be adjusted to these new standards. When an earthquake affects a town, danger is mostly caused by building failure. However, injuries and fatalities are due to the spatial and temporal coincidence between the individual and the danger. In this context, we propose an approach focused on the individual. During a seismic crisis, individual mobility appears to be the element that will allow the spatial coincidence between the danger and the individual. We analyzed individual mobility during seismic crisis by collecting very precise information regarding spatial and temporal aspects of mobility through qualitative interviews. Simultaneously, we carried out a study of dangers observed in the case of Lorca. In general, most of the fatalities caused by earthquakes occur inside collapsed buildings. However, in the case of low-to-moderate-intensity earthquakes, danger is related to the fall of non-structural elements, especially frontage elements. By combining spatial and temporal mobility of individuals with dangers, we conclude that individual mobility is a determinant factor of human exposure. The factors that will determine mobility are mainly related to the immediate protection measures as well as the family organization prior to the town evacuation. Finally, spatial analysis allowed assessing dangers. The associated uncertainty of this evaluation makes it difficult a more accurate study, but offers perspectives for future work. This work proposes the adaptation of a methodology to collect and analyze spatial and temporal dynamics related to individuals. Developed initially for flash flood analysis, this methodology is transferable to future events, enabling comparative studies
Vandervellen, Pascale. "La facture du piano dans les provinces belges des origines à 1851". Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210716.
Texto completoDoctorat en Histoire, art et archéologie
info:eu-repo/semantics/nonPublished
Maître, Anne. "Les peintures polyuréthanes en réparation automobile : développement de méthodes d'évaluation des niveaux d'exposition et approche de la toxicité humaine". Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10147.
Texto completoHoang, Le Ha. "Contribution à la modélisation tridimensionnelle des interactions champ électromagnétique – corps humain en basses fréquences". Phd thesis, Ecole Centrale de Lyon, 2007. http://tel.archives-ouvertes.fr/tel-00203230.
Texto completoLesuffleur, Thécla. "Les proprietes de resistance et d'adaptation des cellules de la lignee cancereuse colique humaine ht-29 a des conditions de contrainte metabolique (exposition au 5-fluorouracile et au methotrexate) sont liees a leur capacite de se differencier". Paris 7, 1991. http://www.theses.fr/1991PA077116.
Texto completoScorretti, Riccardo. "Caractérisation numérique et expérimentale du champ magnétique B.F. généré par des systèmes électrotechniques en vue de la modélisation des courants induits dans le corps humain". Phd thesis, Ecole Centrale de Lyon, 2003. http://tel.archives-ouvertes.fr/tel-00140131.
Texto completoHuang, Yuanyuan. "Etude de l'exposition d'une population à un réseau de communication sans fil via les outils de dosimétrie et de statistique". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2017. http://www.theses.fr/2017IMTA0009/document.
Texto completoWireless communication technologies, since their introduction, have evolved very quickly and people have been brought in 30 years into a much closer world. In parallel radiofrequency (RF) electromagnetic fields (EMF) are more and more used. As a consequence, people's attentions around health risks of exposure to RF EMFs have grown just as much as their usages of wireless communication technologies. Exposure to RF EMFs can be characterized using different exposure metrics (e.g., incident field metrics, absorption metrics...). However, the existing methodologies are well suited to the maximum exposure assessment for the individual under the worst-case condition. Moreover in most cases, when dealing with exposure issues, exposures linked to RF EMF emitted from base stations (BTS) and by wireless devices (e.g, mobile phones and tablets) are generally treated separately. This thesis has been dedicated to construct and validate a new method for assessing the real day-to-day RF EMF exposure to a wireless network as a whole, exploring the people's daily life, including both downlink and uplink exposures and taking into account different technologies, usages, environments, etc. Towards these objectives, we analyzed for the first time the average population exposure linked to third generation network (3G) induced EMFs, from both uplink and downlink radio emissions in different countries, geographical areas, and for different wireless device usages. Results, derived from device usage statistics, show a strong heterogeneity of exposure, both in time and space. We show that, contrary to popular belief, exposure to 3G EMFs is dominated by uplink radio emissions, resulting from voice and data traffic, and average population EMF exposure differs from one geographical area to another, as well as from one country to another, due to the different cellular network architectures and variability of mobile usage. Thus the variability and uncertainties linked to these influencing factors were characterized. And a variance-based sensitivity analysis of the global exposure was performed for the purpose of simplifying its evaluation. Finally, a substitution model was built to evaluate the day-to-day global LTE induced EMFs exposure of a population taking into account the variability linked to propagation environment, usage, as well as EMFs from personal wireless devices and BTS. Results have highlighted the importance of received power density from BTS to the issue of global exposure induced by a macro LTE network. This substitution model can be further used to analyze the evolution of the wireless network in terms of EMF exposure
Didelot, Céline. "Arrêts du cycle cellulaire et induction d'apoptose pour les lignées de carcinome humain de la tête et du cou HPV-18 positives, après exposition au 5-fluorouracile et aux radiations ionisantes : implication de NF-kB dans la radiosensibilité et l'apoptose spontanée". Nancy 1, 2002. http://docnum.univ-lorraine.fr/public/SCD_T_2002_0316_DIDELOT.pdf.
Texto completoRaeppel, Caroline. "Evaluation de la contamination des atmosphères intérieures et extérieures induite par les usages non agricoles de pesticides". Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00869960.
Texto completoBen, khedher Soumaya. "Rôle de l'exposition professionnelle aux agents biologiques dans les cancers broncho-pulmonaires : Analyse de l'étude cas-témoins Icare". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS394.
Texto completoBackground: Lung cancer is the most common cancer associated with occupational exposures. Although asbestos is the best known occupational etiologic factor, several hypotheses suggest the involvement of some environmental or occupational modifiable factors, much more rarely studied, including biological agents. Endotoxins-toxins being part of the outer membrane of Gram-negative bacilli- are commonly associated with reduced risk of lung cancer, while human papillomavirus infections are suspected of increasing the risk. However, the majority of published studies had small numbers of cases and some methodological issues such as inadequate adjustment for tobacco smoking and occupational exposure to asbestos.Objectives: The aim of the present work is to study the role of biological agents found in the workplace on lung cancer risk and more specifically: (1) to investigate the role of occupational exposure to endotoxins on lung cancer risk, to assess dose-response relationship aspects and possible interactions with history of respiratory disease; (2) to focus on the textile industry, which is a source of high exposure to endotoxins, by examining the risk of lung cancer associated with occupational exposure to textile dust; (3) to study the risk of lung cancer in the meat industry by testing the hypothesis of an exposure to a viral agent.Population and methods: This work was based on a large population-based case-control study, ICARE. Cases and controls were recruited from 10 French departments. Incident cases were identified through French cancer registries. A total of 2,926 lung cancer cases (2,276 men and 650 women) and 3,555 controls (2,780 men and 775 women) were included. Detailed information on lifetime occupation was collected through standardized questionnaires. Jobs and sectors were coded according to the ISCO 1968 and the NAF 2000 classifications.Results: Our results showed an inverse association between exposure to endotoxins and lung cancer risk particularly among livestock (all types) and waste collection and treatment workers. Negative trends were shown with duration and cumulative exposure. Furthermore, our findings do not the existence of strong association between occupational exposure to textile dust and lung cancer. A decreased risk was suggested for distant exposures and for work with cotton fibres (OR = 0.7; 95% CI [0.5-0.9]). On the other hand, we observe a significantly increased risk among meat workers OR = 1.46 [1.1-2.1]). However, the history of hand warts does not seem to have any modifying effect on the association between work in the meat industry and the risk of lung cancer.Conclusion: Our findings support the important role of occupational exposures as a determinant of lung cancer risk. This confirms the inverse associations between endotoxin exposures and the risk of lung cancer strongly suggesting an anti-tumor effect of endotoxins towards the lung. This also seems to indicate that working in the meat industry is a risky situation for lung cancer without, however, formally concluding about the involvement of human papillomavirus infections
Corbel, Tanguy. "Mécanismes toxicocinétiques impliqués dans l'exposition foetale au Bisphénol A". Thesis, Toulouse, INSA, 2013. http://www.theses.fr/2013ISAT0034/document.
Texto completoBisphenol A (BPA) an endocrine disruptor interfering with developmental processes in rodents, raises the question of risk for human health related to fetal exposure to BPA. The goal of this work was to determine the toxicokinetic mechanisms involved in fetal exposure to BPA. The disposition of BPA and its metabolites in the maternal-placental-fetal unit in an in vivo ovine model enabled us to identify the placental transfer and the fetal-placental metabolism as the major determining factors of fetal exposure to BPA. Bidirectional placental transfer of BPA occurs by passive diffusion leading to a ratio of free BPA between the fetal and maternal plasma concentrations of about 1. By contrast, the permeability of BPA-G is very limited, particularly in materno-to-fetal direction. The hepatic conjugation activities were very low in ovine fetus at an early stage of development and increased throughout pregnancy. Hydrolysis of BPA conjugates observed ex vivo into fetal ovine gonads could lead to local exposure to native BPA. Altogether, these results suggest that the early stage of pregnancy is a critical window of exposure for the developing fetus
Allodji, Setcheou Rodrigue. "Prise en compte des erreurs de mesure dans l'analyse du risque associe a l'exposition aux rayonnements ionisants dans une cohorte professionnelle : application à la cohorte française des mineurs d'uranium". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00763492.
Texto completoHulo, Sébastien. "Le condensat d'air exhalé : une nouvelle matrice pour évaluer l'exposition pulmonaire professionnelle". Phd thesis, Université du Droit et de la Santé - Lille II, 2014. http://tel.archives-ouvertes.fr/tel-01060978.
Texto completoSwiha, Stéphanie. "Optimisation du suivi de l'exposition aux hydrocarbures aromatiques polycycliques pendant la grossesse avec le développement et la validation de méthodes analytiques et biologiques Analysis of polycyclic aromatic hydrocarbons in human biological samples Development of an analytical method for the simultaneous quantitation of 24 regulated Polycyclic Aromatic Hydrocarbons (PAHs) in maternal and umbilical cord sera Validation of the analytical procedure for the determination of 22 regulated polycyclic aromatic hydrocarbons in maternal and umbilical cord sera". Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCB020.
Texto completoPolycyclic Aromatic Hydrocarbons (PAHs) are mainly emitted by human activities and are one of the main pollutant groups in air, soils, waters, and food. Therefore, they are subject to atmospheric, environmental and food monitoring. This study focuses on the particular case of exposure of pregnant women and their fetus, which are at risks. Indeed, PAH exposure can lead to fetal malformations, prematurity and even disorders in children and adult. To date, only a few PAHs regulated by US-EPA were searched and quantified in maternal or umbilical cord blood. Moreover, analytical performance data are often lacking. Hence, this study aims for the first time in France, at developing analytical and biological methods for the monitoring of PAH exposure during pregnancy. In a first part, the simultaneous determination of the 24 regulated PAHs in sera from maternal and umbilical cord bloods was developed. First, the analysis of the 24 PAHs by liquid chromatography and UV and fluorescence detections (HPLC-UV-FD) and by gas chromatography hyphenated to mass spectrometry (GC-MS) were optimized. The sample pretreatment of the plasma samples was next developed. The precipitation of the proteins present in the plasma was optimized with a Design of Experiment to disrupt all the interactions between them and the PAHs. A solid phase extraction (SPE) protocol, with a C18-based sorbent, was next optimized to extract and concentrate the PAHs. To improve the enrichment factors, the elution SPE fractions were next evaporated and 2 approaches were evaluated: a total or a partial evaporation ("last drop" method). The final analytical protocol involving the sample pretreatment followed by HPLC-UV-FD or GC-MS was successfully validated with spiked pooled sera from maternal and umbilical cord bloods with the accuracy profile approach. Then, sera samples from maternal and umbilical cord bloods were analyzed by LC/UV-FD and GC/MS. Finally, the previously developed analytical methods were used for a study with the ex vivo human cotyledon perfusion model. Perfusions were carried out for the first time with a mix of 14 US-EPA PAHs and their placental transfer was demonstrated. In addition, human trophoblast cell cultures with 1 µM with 14 US-EPA PAHs were carried out to evaluate the impact of PAH exposure on placental functions. The dysfunction of certain placental functions such as trophoblast fusion and differentiation, endocrine functions and detoxification functions was demonstrated
Amigou, Alicia. "Etude des facteurs de risque des leucémies de l'enfant". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00954463.
Texto completoDumas, Milne Edwards Orianne. "Risques professionnels dans l'asthme". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00914719.
Texto completoSassi, Syrine. "Essays on production market competition". Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC0125.
Texto completoThis dissertation investigates the effect of product market competition on corporate decisions and firm valuation. It is a collection of three essays. The first one examines the role of competition in driving the choice of debt source. Using a large sample of U.S. listed firms over the period 2001-2013, we show that product market competitive pressure is negatively associated with bank debt financing. This result is consistent with the view that competition plays an effective governance role that disciplines managers, and hence substitutes for the need to bank strict monitoring. In further analysis, we also show that the negative impact of competition on bank debt financing is stronger for firms with a higher exposure to competition and tighter financial constraints as they are more sensitive to external market discipline.The second essay explores whether product market competition matters for investment decisions, and more specifically labor investment decisions. To test our research hypotheses, we consider a large sample of U.S. listed firms over the 1998-2013 period and provide strong evidence that product market competitive pressure distorts labor investment efficiency. This result highlights the risk-increasing effect of competition. To the extent that firms in competitive industries have lower profit margins and higher bankruptcy risk, they are more willing to under-invest in labor in order to reduce labor costs and avoid further earnings declines. In addition, our cross-sectional tests show that the negative impact of competition on labor investment efficiency is intensified for firms with a higher exposure to competition, tighter financial constraints, and higher labor unionization rates.The third essay further investigates the implications of product market competition by examining its impact on the cost of equity capital which is viewed as one of the key considerations for managers in their investment and financing decisions. We employ a large panel of U.S. listed firms from 1998 to 2013 and find that firms facing intense competitive pressure have a lower cost of equity financing. Additionally, we show that the role of competition in reducing equity financing costs is more pronounced for firms with a higher exposure to competition and firms with poorer governance quality. Taken together, our findings suggest that product market competition serves as an external disciplinary mechanism that improves investors’ beliefs in the stock market, hence leading to a lower cost of equity capital
Adamopoulos, Dionysios. "Environmental determinants of arterial stiffness and wave reflection: pathophysiological mechanisms and clinical implications". Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209744.
Texto completoStudy 1: Effects of cold exposure on central and peripheral vascular tone. Our first study explored the effects of cold exposure on aortic stiffness and peripheral microvascular tone. We observed that cold exposure, in addition to its chronotropic effects, provoked an increase in aortic stiffness, as assessed by aortic pulse wave velocity, as well as significant vasoconstriction of peripheral arterioles in the microcirculation. Moreover, we explored the magnitude of this effect in a different population (Black subjects of African origin), which is traditionally characterized by exaggerated reactions to adrenergic stimuli. We noted that the vascular reactions, in terms of both aortic stiffness and microvascular vasoconstriction, were more profound in Black Africans than in age-matched Caucasian-Whites. These results argue for a direct effect of cold exposure on arterial stiffness and peripheral vascular tone, probably through activation of the orthosympathetic system.
Study 2: Exposure to ambient particulate matter and arterial stiffness. We explored the effects of acute exposure to outdoor particulate matter on aortic stiffness and aortic wave reflection. We studied the relationship between central hemodynamic parameters and ambient concentration of particulate matter in a population of patients who attended the Hypertension Clinics of Athens University. After statistical correction for a number of potential confounders, we did not observe an association between ambient concentrations of particulate matter and aortic stiffness. However, in men, particulate matter concentration was related to the amplitude of the reflected wave reaching the aorta from the periphery. These results suggest a direct acute interaction between particulate matter concentration and vascular tone, leading to an enhanced arterial wave reflection.
Study 3: The role of nicotine on the vascular effects of environmental tobacco smoke. Environmental tobacco smoke is considered as the most important source of particulate matter in the indoor environment. We recently demonstrated that exposure to tobacco smoke augmented wave reflection, an effect that was not seen after equivalent exposure to the smoke of non-tobacco, herbal cigarettes. We also noticed that the increased wave reflection was proportional to the plasma concentrations of nicotine. However, a direct causal effect between nicotine, arterial wave reflection and aortic stiffness has never been clearly demonstrated. We observed that increasing nicotine plasma concentration to levels comparable to those seen after extensive exposure to environmental tobacco smoke, provoked an increase in both aortic stiffness and arterial wave reflection after correction for heart rate and blood pressure changes. These results confirm the significant participation of nicotine in the vascular effects of passive smoking.
Conclusions. Globally, our results reveal the deleterious effects of cold, particulate matter exposure, and nicotinic stimulation on arterial stiffness, peripheral microcirculation and aortic wave reflection. The hemodynamic modifications associated with these effects may at least partially explain the causal relation between cold exposure, ambient air pollution and cardiovascular mortality.
Introduction-Objectifs. Le système cardiovasculaire est en relation directe et constante avec l’environnement. L’exposition au froid, la pollution atmosphérique et le tabagisme passif sont associés à des événements cardiovasculaires aigus graves et même fatals. La rigidification des artères et l’intensification de la réflexion de l’onde de pouls au niveau de l’aorte accompagnent le vieillissement et prédisent un risque cardiovasculaire accru. Nous avons testés l’hypothèse que les effets cardiovasculaires délétères des facteurs environnementaux comportent une altération des propriétés élastiques artérielles. Ceci pourrait être un des mécanismes physiopathologiques qui lie la mortalité cardiovasculaire aux variables environnementales.
Étude 1 :Exposition au froid ;effets centraux et périphériques. Notre première étude portait sur l’effet de l’exposition au froid sur la rigidité aortique et le tonus vasculaire des artérioles périphériques. Nous avons démontré que l’exposition au froid, hormis ses effets chronotropes, provoquait une augmentation de la rigidité artérielle – mesuré par la vitesse de l’onde de pouls au niveau de l’aorte - ainsi qu’une vasoconstriction importante au niveau des artérioles de la microcirculation. Nous avons ensuite déterminé l’amplitude de cet effet dans une autre population (sujets Africains-Noirs) qui se caractérise par des réactions plus prononcées aux différentes stimulations adrénergiques. Nous avons observé que les réactions vasculaires, tant au niveau de la rigidité aortique qu’au niveau de la microcirculation, étaient plus marquées chez les Africains-Noirs que chez les Caucasiens. Ces résultats révèlent un effet délétère de l’exposition au froid sur la rigidité aortique et le tonus vasculaire des artères périphériques, probablement via une activation du système orthosympathique.
Étude 2 :Exposition aux microparticules atmosphériques et rigidité artérielle. Nous avons ensuite investigué les effets de la pollution atmosphérique sur la rigidité artérielle et la réflexion de l’onde de pouls vers l’aorte. Nous avons étudié la relation entre les paramètres hémodynamiques centraux et la concentration atmosphérique de microparticules dans une population de patients qui ont consulté la Clinique Universitaire d’Hypertension Artérielle d’Athènes. Après correction statistique pour les facteurs confondants, nous n’avons pas observé de corrélation entre la rigidité artérielle et le taux de microparticules atmosphériques dans l’ensemble de la population investiguée. Par contre, si on restreint l’analyse aux résultats obtenus chez les sujets masculins, on s’aperçoit que la concentration atmosphérique de microparticules était associée de façon significative avec l’amplitude de l’onde réfléchie par la périphérie vers l’aorte et la pression pulsée aortique. Ces résultants suggèrent un effet direct des microparticules au niveau de la microcirculation. L’augmentation de l’amplitude de l’onde réfléchie consécutive à une vasoconstriction périphérique, modifie vraisemblablement les pressions au niveau de l’aorte chez le sujet masculin lors de pics de pollution.
Etude 3 :Le rôle de la nicotine dans les effets vasculaires du tabagisme passif. Le tabagisme passif est considéré comme la source la plus importante d’émission de microparticules au niveau domestique. Cependant, la composition chimique des particules semble jouer un rôle essentiel sur les ondes de réflexion. Nous avons démontré récemment que l’exposition passive à la fumée des cigarettes du tabac augmente l’intensité de la réflexion de l’onde de pouls. Ceci n’a pas été observé avec l’exposition à la fumée des cigarettes non tabagiques, en dépit d’une concentration ambiante tout à fait comparable de microparticules. Par ailleurs, nous avons observé que l’augmentation de l’incidence de l’onde de pouls au niveau de l’aorte était fortement associée à la concentration plasmatique de la nicotine. Un lien causal entre la nicotine, réflexion de l’onde de pouls et rigidité artérielle n’avait jamais clairement été établi. Nous avons testé cette hypothèse en administrant la nicotine pure chez des sujets sains. Nous avons observé que l’augmentation des taux plasmatiques de la nicotine à des valeurs comparables à celles qui surviennent après une exposition intensive au tabagisme passif, intensifiait la réflexion de l’onde de pouls et augmentait la rigidité artérielle. La correction statistique pour l’augmentation de la fréquence cardiaque et l’augmentation de la pression artérielle en réponse à la nicotine ne modifiait pas ces conclusions. Nos résultats démontrent ainsi les effets cardiovasculaires importants de faibles concentrations de nicotine, similaires à ceux qui sont atteints en cas d’exposition à un tabagisme passif.
Conclusions. Nos résultats révèlent les effets néfastes de l’exposition au froid et aux microparticules atmosphériques sur la rigidité artérielle, la microcirculation périphérique et la réflexion de l’onde de pouls. Nous avons pu également démontrer le rôle de la stimulation nicotinique dans les effets vasculaires aigus du tabagisme passif, comme en témoigne l’augmentation de la réflexion de l’onde de pouls au niveau aortique. Ces modifications hémodynamiques favorisent l’ischémie myocardique, et constituent un des mécanismes par lesquels l’exposition au froid et à la pollution atmosphérique favorisent la pathologie cardiovasculaire.
Doctorat en Sciences médicales
info:eu-repo/semantics/nonPublished
Jafari, Seyedfaraz. "Near-field millimeter-wave radio-frequency exposure analysis". Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAT034.
Texto completoThis thesis aims to determine the absorbed power density (APD) considering the coupling and multiple reflections between the antenna and the human body, which poses challenges in assessing APD due to their close proximity.The first part of the thesis explores the concept of measuring APD inside a skin tissue phantom, specifically focusing on its application in 5G technologies.However, measuring APD inside the skin tissue phantom is limited due to the shallow penetration depth of fields at millimeter and quasi-millimeter waves. To overcome this limitation, a reconstruction technique is employed, utilizing the backward plane-wave spectrum(PWS) method. The electric field is sampled at a specific distance within the phantom, enabling the determination of APD at the human skin surface.In the second part, a non-invasive approach based on the dyadic Green's function (DGF) is proposed for APD assessment. This method takes into account the coupling between the human skin model and the device under test (DUT). The entire space is dividedinto two half-spaces : the upper half-space (z > 0) is filled with air, where the antenna is positioned, and the lower half-space is filled with an equivalent human skin liquid or solid. The electric field integral equation (EFIE), based on spatial DGFs, is solved using the method of moments (MoM) to reconstruct the equivalent currents. The electric field is sampled on the surface of a hemisphere surrounding the antenna, and the APD is evaluated based on the reconstructed equivalent currents beneath the air-phantom interface.In addition to the proposed techniques, the thesis investigates the measurement requirements for both approaches, including E-field measurement uncertainty, sampling angular resolution, and the required size of the phantom.The findings demonstrate that the proposed techniques present a novel methodology for assessing APD, taking into consideration the coupling between the human body and the antenna, particularly in the context of exposure to handheld devices operating above 6GHz
Khmiri, Imen. "Contribution à l’évaluation de la toxicocinétique humaine du bisphénol S". Thesis, 2020. http://hdl.handle.net/1866/25215.
Texto completoThe measurement of bisphenol-S (BPS) and its glucurono-conjugate (BPSG) in urine may be used for the biomonitoring of exposure in populations. However, this requires a thorough knowledge of their toxicokinetics. The time courses of BPS and BPSG were assessed in accessible biological matrices of orally and dermally exposed volunteers. Under the approval of the Research Ethics Committee of the University of Montreal, six volunteers were orally exposed to a BPS-d8 deuterated dose of 0.1 mg/kg body weight (bw). One month later, 1 mg/kg bw of BPS-d8 were applied on 40 cm2 of the forearm and then washed 6 h after application. Blood samples were taken prior to dosing and at fixed time periods over 48 h after treatment; complete urine voids were collected pre-exposure and at pre-established intervals over 72 h postdosing. Following oral exposure, the plasma concentration–time courses of BPS-d8 and BPSG-d8 over 48 h evolved in parallel and showed a rapid appearance and elimination. Average peak values (±SD) were reached at 0.7 ± 0.1 and 1.1 ± 0.4 h postdosing and mean (±SD) apparent elimination half-lives (t½) of 7.9 ± 1.1 and 9.3 ± 7.0 h were calculated from the terminal phase of BPS-d8 and BPSG-d8 in plasma, respectively. The fraction of BPS-d8 reaching the systemic circulation unchanged (i.e. bioavailability) was further estimated at 62 ± 5% on average (±SD) and the systemic plasma clearance at 0.57 ± 0.07 L/kg bw/h. Plasma concentration–time courses and urinary excretion rate profiles roughly evolved in parallel for both substances, as expected. The average percent (±SD) of the administered dose recovered in urine as BPS-d8 and BPSG-d8 over the 0–72 h period postdosing was 1.72 ± 1.3 and 54 ± 10%. Following dermal application, plasma levels were under the lower limit of quantification (LLOQ) at most time points. However, peak values were reached between 5 and 8 h depending on individuals, suggesting a slower absorption rate compared to oral exposure. Similarly, limited amounts of BPS-d8 and its conjugate were recovered in urine and peak excretion rates were reached between 5 and 11 h postdosing. The average percent (±SD) of the administered dose recovered in urine as BPS-d8 and BPSG-d8 was about 0.004 ± 0.003 and 0.09 ± 0.07%, respectively. This study provided greater precision on the kinetics of this contaminant in humans and, in particular, evidenced major differences between BPA and BPS kinetics with much higher systemic levels of active BPS than BPA, an observation explained by a higher oral bioavailability of BPS than BPA. These data should also be useful in developing a toxicokinetic model for a better interpretation of biomonitoring data. Overall, this study provided greater precision on the kinetics of this contaminant in humans. These data will be useful in developing a toxicokinetic model for a better interpretation of biomonitoring data. For the oral route of exposure, the apparent similar absorption rate of BPS-d8 and BPSG-d8 after oral exposure suggests that free and conjugated forms of BPS reach the systemic blood circulation at about the same time interval. This indicates a first-pass effect in the liver, i.e. a conjugation of BPS-d8 in the liver before reaching the systemic circulation. Nevertheless, despite the first-pass effect, the bioavailability of BPS-d8 and therefore the proportion of unconjugated active form of BPS reaching the systemic bloodstream is relatively high. It is actually much higher than that of BPA. Free BPS was also found to have a longer plasma residence time than BPA. For the dermal route of exposure, data show that BPS quickly reaches systemic blood circulation and is therefore rapidly absorbed by skin. On the other hand, its elimination from the body appears to be slower after dermal exposure compared to its elimination after oral exposure. Furthermore, despite the fact that BPS is rapidly absorbed through the skin, the dermal absorption fraction was very small compared to the oral absorption fraction.
Roy, Edith. "Le monde du corps : exposition anatomique de corps humains véritables, de Gunther Von Hagens : stratégies brouillées pour un succès assuré". Mémoire, 2009. http://www.archipel.uqam.ca/2165/1/M10962.pdf.
Texto completo