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Cinquante nuances de noir. Problèmes de diagnostic en archéologie du feu: études de cas du Bassin Mosan belge au MIS 3
No full textL’objectif de ce travail est de contribuer à la réflexion méthodologique autour du problème de l’identification des traces de feu contrôlé sur les sites paléolithiques. L’étude se focalise plus particulièrement sur la question des gisements « mal documentés », c’est-à-dire les gisements pour lesquels les données de terrain, et en particulier les données contextuelles (données spatiales, contexte géologique et archéologique), sont imprécises, partielles ou totalement absentes. Une approche méthodologique adaptée aux spécificités des gisements « mal documentés » est d’abord définie à partir d’un état de l’art des méthodes analytiques et des modèles interprétatifs utilisés pour l’identification et la caractérisation des témoins de combustion. Deux cas représentatifs sont ensuite traités :la collection Dupont du Trou Magrite (Pont-à-Lesse, Province de Namur) qui constitue un exemple représentatif de gisements fouillés à la fin du 19e ou au début du 20e siècle et le Tiène des Maulins (Rochefort, Province de Namur) qui permet d’aborder les problèmes spécifiques liés à la révision de données issues de fouilles récentes. Pour le Trou Magrite, l’analyse s’appuie sur un référentiel des différents types de traces caractéristiques de l’altération thermique du silex et de l’os établi à partir d’une synthèse bibliographique et de l’examen de corpus expérimentaux (collection d’ossements brûlés du CEPAM, collection de silex brûlés de M. Horevoets et collection d’os brûlés issus d’expérimentations effectuées dans le cadre de cette thèse) et archéologiques (issus de plusieurs gisements :Scladina, Trou Magrite, Trou du Diable et Trou de l’Abîme). Même si le degré de résolution visé par l’analyse a dû être adapté en fonction de la documentation disponible, cette étude montre qu’il est possible de déterminer l’existence de feu anthropogénique dans un site anciennement fouillé pour lequel presque aucune donnée stratigraphique fiable n’a été enregistrée. L’analyse critique des données de terrains et des résultats des analyses physiques et géochimiques (thermoluminescence, diffraction et fluorescence des rayons X, analyses thermiques simultanées, MEB + EDS, lames minces) réalisées sur les structures de combustion supposées du Tiène des Maulins met quant à elle en lumière deux problèmes importants :la difficulté de déterminer l’origine anthropique d’une structure dans le cadre d’une démarche de révision, d’une part, et la complexité de l’interprétation des données de laboratoire, d’autre part. Si ces deux études de cas illustrent bien les difficultés posées par les lacunes dans les données contextuelles, elles démontrent également qu’une révision critique des données peut permettre de proposer une nouvelle interprétation des traces de feu avec un degré de confiance relativement élevé.Doctorat en Histoire, histoire de l'art et archéologieinfo:eu-repo/semantics/nonPublishe
Genotype-phenotype Correlation in Late-onset Glycogen Storage Disease Type II, Early Diagnosis and Prognostic Determinants
No full textGlycogen storage disease type II (GSDII) is an autosomal recessive lysosomal storage disorder caused by acid alpha-1,4-glucosidase (GAA) deficiency. This study aimed to provide an in-depth description of a late-onset GSDII (LO-GSDII) cohort (n=36) and assess potential genotype-phenotype correlation. We performed a clinical record-based study, some patients (n= 19) were also followed prospectively. Phenotypes were highly variable. We focused our clinical assessment onrespiratory failure, as it is the most frequent cause of death in LO-GSDII. In addition to standard spirometric measures, in a subgroup of patients (n = 10) we utilized a new tool, optoelectronic plethysmography (OEP), to investigate the pathophysiology of respiratory muscle impairment.The GAA gene was sequenced in every patient, and pathogenic mutations were identified inall of them. Almost all (35/36) patients carried the same mutation on one allele, IVS1-32-13T>G, which was in compound heterozygosity with a variety of other GAA mutations. To investigate genotype-phenotype correlation, we divided the patient cohort in two groups, according to the severity of the mutation on the second allele. The respiratory function study focused on diaphragmatic weakness. According to the change in forced vital capacity in supine position (ΔFVC), we defined patients with ΔFVC>25% ashaving diaphragmatic weakness (DW) and those with ΔFVC<25% as without diaphragmatic weakness (noDW). We measured pulmonary function and chest wall volumes using OEP inboth groups. We found a good correlation between the supine abdominal contribution to tidal volume (%VAB) and ΔFVC. Patients showed reduced chest wall and abdominal inspiratory capacity and low abdominal expiratory reserve volume. In terms of genotype-phenotype correlation, we counted more subjects in the group with severe second mutations (n=21) who had severe motor disability and respiratory dysfunction. However, this finding remains preliminary because differences were not significant, likely because of small sample size. Finally, in two smaller substudies, we investigated the occurrence of urinary and fecal incontinence in LO-GSDII, and reported a possibly non-fortuitous association of LO-GSDII and hydromyelia in two individuals. Overall, this work 1) provided new insight into genotype-phenotype correlation in GSDII, suggesting that it is of complex nature; 2) refined the analysis of respiratory muscle impairment and showed the utility of OEP for respiratory assessment in this neuromuscular disorder, and possibly in others as well; 3) indicated some so far little studied phenotypic features of LO-GSD-II that deserve further investigation.Doctorat en Sciences médicales (Médecine)info:eu-repo/semantics/nonPublishe
Le khap tai dam, catégorisation et modèles musicaux. Etude ethnomusicologique chez les Tai des hauts plateaux du Laos.
No full textCette thèse étudie le chant "khap" de l’ethnie des Tai Dam du Laos à partir de la notion de modèle musical. Abordé au travers du concept de la pertinence, son principal objectif est la mise en lumière des compétences liées au chant, c’est-à-dire des connaissances abstraites nécessaires à l’interprétation et la catégorisation du chant. Fil rouge de ce travail, c’est au départ de la notion de modèle que sont construits les différents chapitres. Partant d’une considération d’ordre musical, sont mis au jour les mécanismes de transmission du chant, les rapports entre tons parlés et chantés, ainsi que les différents mécanismes de catégorisation musicale et identitaire. La thèse montre l’imbrication de chacun de ces aspects et la pertinence de la mobilisation de plusieurs disciplines dans la réalisation de cette recherche :musicologie, anthropologie et linguistique. C’est dans une perspective intégrant les points de vue étiques et émiques et par le développement d’une méthodologie adaptée aux particularités du sujet que sont discutés les différents axes de la recherche.This research studies the singing named "khap" of Tai Dam ethnic group in Laos, through the notion of musical model. Its main objective, approached with the concept of relevance, is to highlight the competences linked to the singing, that is to say the abstract knowledge needed for the interpretation and the categorisation of "khap Tai Dam". The principle of musical model is the common theme of this research, and is the starting point of every chapter. Starting from musical considerations, this PhD highlights the mechanisms of musical transmission, the relationships between spoken and musical tones, as well as the different mechanisms of musical categorisation and identity categorisation. This work shows the interweaving of every of those aspects and the relevance of using different disciplines: musicology, anthropology and linguistic. The different lines of this work are approached with a perspective mobilizing etic and emic perspectives, and follow a methodology adapted to the specificities of the topic.Doctorat en Sciences politiques et socialesinfo:eu-repo/semantics/nonPublishe
Hybrid materials for potential thermoelectric applications
No full textNew lamellar hybrid materials, potentially usable in thermoelectric applications at room temperature, were synthesized from substituted phosphonic acids and were characterised.The intercalation of conductive polymers was also tested. The hybrid materials were synthesized by hydrothermal process by mixing a zinc or a cobalt inorganic salt and an organic molecule made of a thiophene aromatic ring with a phosphonic acid function grafted in position 2 or 3: 2-thienylphosphonic acid or 3-thiernylphosphonic acid. X-Ray diffraction on single crystal allowed the determination of the lamellar structure of these compounds. It is composed of alternating organic and inorganic layers. For the compounds obtained with the 2 thienylphosphonic acid, incommensurate structures were obtained. The compounds did not present any intrinsic electrical conductivity. Therefore, to induce the electrical conductivity within the organic layer, two strategies were chosen: i) the intercalation of pyrrole or thiophene monomers in the organic layer followed by an in-situ polymerization in order to obtain a conductive polymer; ii) the direct in-situ polymerization of the thiophene involved in the organic layer of the material to form a conductive polymer.De nouveaux matériaux hybrides lamellaires, potentiellement utilisables pour des applications thermoélectriques à basse température, ont été synthétisés à partir d’acides phosphoniques substitués et ont été caractérisés. Des essais d'intercalation de polymères conducteurs ont également été menés. Les matériaux ont été synthétisés par voie hydrothermale à partir de sels inorganiques de zinc ou de cobalt et d'une molécule organique constituée d’un cycle thiophène sur lequel est greffé une fonction acide phosphonique en position 2 ou 3 :l'acide 2-thiénylphosphonique ou l'acide 3-thiénylphosphonique. La structure lamellaire des composés a été résolue par diffraction des rayons X sur monocristal. Elle est constituée d’une alternance de couches organiques et inorganiques. Dans le cas des composés obtenus à partir de l'acide 2-thiénylphosphonique des structures incommensurables ont été obtenues. Afin d’introduire une conductivité électrique au sein de la couche organique de ces matériaux, qui ne présentent pas de conductivité électrique intrinsèque, deux stratégies ont été envisagé :i) l'intercalation de monomères thiophène ou pyrrole dans le réseau organique puis la polymérisation de ces derniers pour former un polymère conducteur, ii) la polymérisation directe des cycles thiophènes impliqués dans la couche organique du matériaux pour former un polymère conducteur.(FSA - Sciences de l'ingénieur) -- UCL, 2016Accès restreint15/01/2016(FSA - Sciences de l'ingénieur) -- UCL, 2016Anglai
Molecular and cellular mechanisms of the pro-fibrotic effects of carbon nanotubes
No full textCarbon nanotubes (CNT) are molecular-scale tubes of graphene sheets rolled into cylinders with peculiar characteristics that make them highly attractive for numerous industrial applications. Thus, investigating the health hazards of CNT is of great importance in view of the increased potential for human exposure within occupational, environmental, and consumer environments. Several studies have already shown that CNT can induce inflammatory, fibrotic or carcinogenic reactions in the lung of experimental animals. These toxic responses appear, however, determined by the physico-chemical characteristics of CNT. This work focuses on lung fibrosis, a process involving the proliferation and activation of fibroblasts. The main objectives were (1) to understand the mechanisms mediating the fibrogenic activity of CNT by investigating their direct and indirect (via macrophages and epithelial cells) effects on fibroblasts and (2) to develop valid in vitro models to predict the fibrogenic activity of CNT. An additional objective was to assess and to identify physico-chemical properties of CNT that determine their fibrogenic activity. As CNT have been shown to interact with several toxicological assays, we first designed an adapted protocol of the WST-1 cell viability assay to avoid or take into account interferences of nanomaterials. Our data demonstrate that the direct in vitro activity of CNT on fibroblast proliferation strongly reflects their fibrogenic activity in vivo, supporting a predictive value of this in vitro endpoint. Kinase receptors, ERK 1/2 signaling and endocytosis were identified as mechanisms involved in fibroblast proliferation induced by fibrogenic CNT. In addition, we showed that CNT indirectly stimulate fibroblast differentiation, via epithelial cells and macrophages, highlighting the contribution of these cells in the development of fibrosis. We found that the release of IL-6 from epithelial cells is another useful biomarker, in addition to the proliferative activity of CNT on fibroblasts, to predict the toxic potential of CNT. The results also confirm that the length and diameter of CNT constitute important physico-chemical determinants of their capacity to induce lung fibrosis. Finally, we have organized, analyzed and integrated all the current knowledge concerning the mechanisms of action of CNT relevant for their pro-fibrotic activity in a tentative adverse outcome pathway (AOP). This provides a global picture of the complex network of events contributing to the fibrogenic activity of CNT, and allows identifying predictive in vitro endpoints useful for the toxicological assessment of new and emerging CNT.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Accès libre11/05/2016(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Anglai
Remodelling the genetics of spinocerebellar entities :new genes, phenotypes, and transmission modes lead to new concepts
No full textHereditary cerebellar ataxias (HCA) and spastic paraplegias constitute both ends of the neurodegenerative spectrum of spinocerebellar entities (SCE). Theses diseases are marked by a pronounced heterogeneity, both clinically, with various additional neurological or extraneurological signs, and genetically. They can indeed follow all transmission modes, and mutations in a myriad of genes have been described. SCE is hence a group of diseases that benefit greatly from Next-Generation Sequencing technologies. This work reports both screenings of large cohorts of patients with either panel or whole exome sequencing, as well as family studies. The latter allowed us to describe new modes of transmission for genes previously involved in human pathology, with either similar protein dysfunction, or loss- versus gain-of-function. We also describe two new genes implicated in a form of autosomal dominant HCA (CACNA1A), and an autosomal recessive subtype of dystonia and cerebellar atrophy (TOR1AIP1). Our results are illustrative of the genetic remodelling underway in complex genetic diseases, with permanent questioning of genotype-phenotype correlations. We discuss the how and the why of molecular diagnosis in this new era of sequencing.(MED - Sciences médicales) -- UCL, 2016Accès interdit10/05/2016(MED - Sciences médicales) -- UCL, 2016Anglai
Marguerite Yourcenar, autre portrait d'une voix :esthétique d'un écrivain au miroir du néoclassicisme de l'Entre-deux-guerres
No full textThis study proposes to reexamine the works of Marguerite Yourcenar (1903-1987), focussing on the relation to the 20th century’s neoclassicism. By means of literary- and cultural-history approaches, it analyzes the gaps or connections between her and the literary or artistic currents in the Interwar period. The first part clarifies how the author moulded her view of ancient Greece and Rome, which affected her works. It examines published and unpublished documents conserved in Harvard University and in Petite Plaisance: the notebook in which her father copied the poems chosen by him; the collection of poems by Yourcenar, The Gods didn’t die (1922), and its related typed texts “Album of ancient poems” (1917-1965); the book De Profun- dis of Oscar Wilde which includes her reading notes. The second part traces the trajectory of the young novelist, which shows that she was not indifferent to the major currents; the NRF, the return to the order and the discovery of the new image of Greece. We examine especially her writings published in several magazines and her letters written in the thirties as well as her works concerning this period. The third part proposes to regard Yourcenar as an anti-modernist and a dandy, by clarifying her neoclassical aesthetics.La présente étude vise à réexaminer l’œuvre de Marguerite Yourcenar (1903-1987) sous le signe du néoclassicisme du XXe siècle. À travers une approche d’histoire littéraire et culturelle, sont analysés les écarts ou rapprochements qu’elle a opérés par rapport aux courants littéraires et artistiques de son temps, notamment ceux de l’Entre-deux-guerres. La première partie cherche à mettre au jour l’enjeu et la modalité de son rapport à l’Antiquité, en examinant, outre ses textes publiés, les documents inédits conservés aux archives à l’Université Harvard et à Petite Plaisance :le cahier dans lequel son père a copié des poèmes choisis ;le recueil Les Dieux ne sont pas morts (1922) et le tapuscrit de poèmes, « Album de vers anciens » (1917-1965) ;l’exemplaire de De Profundis sur lequel elle a laissé des traces de sa lecture. La deuxième partie retrace, en observant les textes publiés par l’auteur dans plusieurs revues ainsi que la correspondance, surtout dans les années trente et dans des écrits postérieurs sur cette période, l’itinéraire d’une jeune romancière qui n’est pas ignorante des courants majeurs — ceux qui se développent autour de la NRF, du courant dit du « retour à l’ordre » et de la découverte d’une nouvelle image de la Grèce — mais maintient un écart subtil entre eux et sa propre production. La troisième partie propose, à travers la caractérisation de son esthétique néoclassique, de définir Marguerite Yourcenar comme une figure de l’antimoderne et du dandy.(LALE - Langues et lettres) -- UCL, 2016Accès restreint05/04/2016(LALE - Langues et lettres) -- UCL, 2016Françai
The effect of gravity on the motor control of landing
Full text linkLanding from a fall is a complex action requiring the prediction of the instant of contact with the ground. Since humans have developed motor actions on Earth, the nervous system and the sensory input processing are optimized to the Earth’s gravity. The aim of this study is to assess human motor control of landing in different conditions of fall initiation, simulated gravity and sensory neural input. Hypergravity was simulated either on Earth with a Subject Loading System (SLS) generating a pull-down force or by turns of an aircraft generating centrifugal forces. Microgravity was simulated in a weightlessness environment during parabolic flights with the SLS. Kinetics, kinematics and muscular activity of the lower limb were recorded. Humans anticipate the contact with the ground, and are able to land and stabilize in all experimental conditions. The interaction with the ground can be illustrated by a stiff spring to resist the impact, which changes to a compliant spring associated with a damper to dissipate the energy. The otolithic system, even perturbed, contributes to the control of landing. Further investigations are still needed to determine the potential use of such landing tasks as countermeasure for preventing injury in sports and/or the detrimental effects of weightlessness induced by spaceflights in astronauts.(MOTR - Sciences de la motricité) -- UCL, 2016Accès libre15/04/2016(MOTR - Sciences de la motricité) -- UCL, 2016Anglai
Prognostic determinants in severe aortic regurgitation
No full textSince the last two decades, aortic valve (AV) repair has emerged as an alternative for AV replacement, as surgery for patients with severe aortic regurgitation (AR). The aim of this thesis is to reevaluate the appropriateness of the guidelines for this new type of surgery, in particular to examine whether it might allow earlier treatment for the management of asymptomatic patients with normal ejection fraction. My works first show that the AV repair improves prognosis of patients. Subsequently we evaluated post operative survival after AV repair according to the guidelines and showed an interest to assess the benefit of an early surgery in asymptomatic patients. Despite that no benefit of an early surgery has been shown, we finally explored and measured a new parameter, the extracellular volume by cMR, able to assess myocardial fibrosis and which should add information in the management of asymptomatic patients with severe AR.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Accès restreint22/04/2016(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Anglai
Impact of tinnitus on cognitive and brain function
No full textTinnitus is a frequent disorder and, despite a constantly growing interest from the scientific community; its pathophysiology is not clear yet. Understanding the cognitive and neurophysiological mechanisms involved in tinnitus is particularly crucial to develop more efficient treatments. The present work brings new evidences regarding the nature of the cognitive deficits associated with tinnitus and their role in its pathophysiology. Here, we showed an alteration of the top-down cognitive control and of the inhibitory control in the auditory and visual modality in tinnitus patients. The deficit in the top-down cognitive control was underlined by dysfunctions in the prefrontal cortex. The impairment in cognitive control observed in tinnitus patients may contribute with the development of chronic tinnitus. The training of executive functions and the modulation of prefrontal cortex activity could be a key target to reduce tinnitus perception and its consequences.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Accès embargo20/01/2016(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2016Anglai