McGill University Thèses et mémoires par auteur commençant par É

In recent years the disposal and the treatment of mine waste has been increasingly causing concern to the mining industry. One of the biggest challenges today is acid mine drainage (AMD), which is associated in particular with sulfide bearing tailings. As a consequence of AMD, heavy metals and sulfates are released into the environment. This project has studied the effect of lime-based treatments in the stabilization of two sulfide tailings, one waste predominately containing pyrite minerals and the second containing pyrrhotite minerals. Different proportions of pozzolans (fly ash and slag) were also added to the lime-tailings mixtures. The physical properties …  Lire la suite

Contexte : Les indications et les résultats de la chirurgie bariatrique chez les personnes âgées souffrant d'obésité morbide demeurent controversés. Nous visions à évaluer la sécurité et les résultats à moyen et à long terme des procédures bariatriques dans cette population de patients. Lieu : Hôpital universitaire, Canada. Méthodes : Il s'agit d'une étude rétrospective monocentrique d'une base de données prospectivement collectée. Nous avons inclus des patients âgés de ≥ 60 ans qui ont subi une gastrectomie verticale (SG), une dérivation gastrique en anse en-Y (RYGB) ou une dérivation biliopancréatique avec un switch duodénal (BPD/DS) entre janvier 2006 et décembre …  Lire la suite

This thesis explores how two Arab-Canadian feminist anthologies, Food for Our Grandmothers: Writings by Arab-American and Arab-Canadian Feminists and Min Fami: Arab Feminist Reflections on Identity, Space & Resistance, exemplify resistance literature by fostering community, producing knowledge, and critiquing power dynamics within multiculturalism, assimilation, and through their content and themes. Using a feminist lens, the study examines how these anthologies, published twenty years apart, form a continuum in fostering alliances and resisting discrimination based on identity, race, class, and sexuality. By focusing on these works, the research addresses the gap in scholarly attention to Arab-Canadian literature, positioning them as platforms …  Lire la suite

Soviet literature of the twenties and thirties is examined in the present study in its relationship to other verbal genres, primarily, the speeches of Party leaders, newspaper rhetoric and political posters. The first four chapters of the dissertation focus on such topics as the reception of Marxist-Leninist discourse by peasants and workers as well as its representation in fiction; the refraction of official discursive formulas in characters' speech and the dialogization of Party rhetoric; the integration of political documents into fiction and their structural function. Particular attention is paid to the way the contamination of Party rhetoric by substandard language …  Lire la suite

L’ostéoporose sénile est souvent associée à une augmentation de gras dans la moelle osseuse. Cette accumulation de gras est une conséquence d’une différentiation prédominante de cellules souches en adipocytes en lieu d’ostéoblastes. Prenant en considération ce changement de différentiation, nous avons décidé d’étudier le gras de la moelle osseuse de trois différentes approches : métabolique, lipo-toxique et régulatrice. Nous avons premièrement observé les effets d’une restriction calorique (RC) sur la qualité osseuse ainsi que sur le gras de la moelle osseuse de rats nourris de caséine ou de soja. Les marqueurs osseux et adipogéniques ont aussi été quantifiés. La RC …  Lire la suite

Cette thèse se propose d'une part d'étudier les relations qui existent entre un texte littéraire donné et les conditions socio-historiques qui lui donnent naissance, et d'autre part, d'essayer de comprendre notre pratique sociale et le rôle qu'elle offre aux individus qui la composent. En choisissant l'autobiographie comme domaine d’analyse, j'ai voulu saisir le sens du concept "genre", étant donné que l’autobiographie constitue, selon la critique, un genre bien défini. Donc, d'un côté faire la description d'une structure littéraire afin de voir si les vieilles classifications qui existent encore ont un sens dans un monde en changement perpétuel, et de l'autre …  Lire la suite

Dans cette thèse nous analysons un cas particulier d’apprentissage actif dans le contexte des demi-espaces, un problème notamment connu sous le nom de localisation de point. En particulier, nous examinons une série d’articles de Kane, Lovett et al., qui étudient l’ ́etroitesse de la borne supérieure théorique sur le nombre de requêtes nécessaires pour résoudre ce probème. De plus, nous explorons des problèmes ouverts liés à ce domaine et démontrons nos approches et nos futures directions de recherche  Lire la suite

The involvement of corticotropin-releasing hormone (CRH) and neuropeptide Y (NPY) in the pathophysiology of anxiety and anxiety-related disorders is well established. The objective of this study is to explore the genetic variations in the CRH and NPY genes in a well-documented behavioral animal model, the vervet monkey (Chlorocebus aethiops sabaeus), in order to uncover a possible association between these polymorphisms and behavioral traits quantitatively extracted following analysis of social behavior and responses to novelty challenges. The vervet CRH and NPY genes were amplified and sequenced; the priority was given to the regions expanding from -1kb upstream of the transcription initiation …  Lire la suite

Dufouil, Carole (Supervisor2)  Lire la suite

Novel amorphous thermoplastic poly(phenylquinoxaline)s (PPQ), poly(aryl ether ketone)s (PAEKs) and poly(aryl ether phthalazine)s have been synthesized. The reaction of an aromatic Schiff's base and a tertiary amine incorporating an activated methylene moiety in the presence of strong base to produce an enamine has been investigated. Hydrolysis of the resulting enamines resulted in deoxybenzoins which were converted to benzils by a mild oxidation reaction. This chemistry was investigated as a possible method for the synthesis of the tetraketone compounds (sometimes called bisbenzils) which serve as monomers for poly(phenylquinoxaline) polymers. Two novel monomers have been prepared, the corresponding polymers with 1,1$ sp …  Lire la suite

Plusieurs pressions anthropogéniques peuvent avoir des effets considérables sur la qualité des ressources d'eau douce. En effet, les modifications hydrologiques causées par la construction de barrage et les opérations subséquentes de maintenance des réservoirs, telles que le marnage hivernal, sont devenues des perturbations anthropogéniques majeures au niveau des écosystèmes aquatiques tempérés et boréaux. Bien que le marnage soit largement reconnu pour altérer la structure et le fonctionnement des écosystèmes littoraux et peu profonds, peu de recherches ont examiné les implications à long terme du marnage sur la qualité de l'eau des systèmes aquatiques pélagiques. Afin d'évaluer les tendances à long …  Lire la suite

Contexte: Selon l'Organisation mondiale de la santé, les collisions routières représentent la principale cause de mortalité chez les jeunes. Les collisions routières sont en grandes partie évitables, mais les mécanismes précis sous-jacents au risque individuel restent encore à identifier. Certains conducteurs à risque sont surreprésentés parmi ceux impliqués dans les collisions routières graves et fatales, incluant ceux faisant un usage abusif de l'alcool. La recherche axée sur les causes de la conduite à risque s'est penchée sur les marqueurs neurobiologiques de la prise de risque, comme le cortisol, la sérotonine et l'adrénaline. La testostérone a reçu beaucoup d'attention en lien …  Lire la suite

By modulating the degree of closure of the outlines, I show that two-dimensional shape processing is rapid for closed stimuli but slow for open stimuli. I further show that search speed can be characterized as a smooth, monotonic function of the degree of closure, supporting the notion of a perceptual closure continuum. This continuum is shown to be naturally parameterized by a dot-spacing metric, and experiments with different types of fragmentation lead to the hypothesis of a Minimax Principle of closure, which imposes a partial ordering over all fragmentations of a given contour. Using search speed as a metric for …  Lire la suite

The problem of computing closed bounding contours from a visual image is addressed. The approach is motivated by the fact that many important image structures are heterogeneous and therefore cannot be segmented by traditional region-based methods based on homogeneity or smoothness constraints. Both psychophysical and computational aspects of the problem are studied. Psychophysical evidence is presented which shows that properties of bounding contour such as closure act as binding features for the segmentation of 2-D shapes, whereas texture (a region property) does not. These psychological results motivate an investigation of local and global issues in the computation of bounding contours …  Lire la suite

Ce mémoire introduit une nouvelle variante du modèle de phase structurale du champ cristallin (XPFC) pour simuler le graphène, un allotrope de carbone en deux dimensions (2D), aussi bien dans sa forme de composant singulier que dans un mélange à deux composants. Dans une certaine mesure, ce travail est motivé par les expériences récentes de production de cristaux de graphène en présence d'hydrogène sur des surface 2D de cuivre utilisant la déposition de vapeur chimique (CVD). Le modèle XPFC est basé sur l'expression de l'énergie libre d'Helmholtz en tant que fonctionnelle de la densité classique jusqu'aux intéractions à deux particules …  Lire la suite

Cette thèse propose une interprétation des travaux de David Graeber publiés pour un grand public afin d'avancer deux arguments concernant le réalisme politique. Les défenseurs d'un tel réalisme pensent que les théoriciens politiques devraient avant tout s'occuper non de modèles abstraits et idéaux mais plutôt d'une réalité politique constituée et compliquée par une série d'actions concrète entre individus. La contribution principale de cette thèse s'inscrit donc dans une série de débats méthodologiques en théorie politique.L'argument premier concerne une écriture politique optimiste et vague, de telle sorte que les réalistes la trouveront trop abstraite et dispersée pour s'inscrire dans le 'vrai' …  Lire la suite

The elevation in temperature of the windings of electric machines is at the present time the dominating factor in limiting their rating. At the beginning of the century, the temperature rise was a minor limitation in the design of a motor, the reason being that the size of the machines was much larger, and they were generally of the open type, a case in which cooling is not much of a problem. [...]  Lire la suite

Patterning of the body axes of the Drosophila embryo depends on maternally expressed genes, some of which function in the follicular epithelium of the developing egg chamber. Many such genes were identified in genetic screens for homozygous mutant females that produce abnormal embryos. However, mutations in zygotically required maternal effect genes are homozygous lethal, and therefore viable females cannot be recovered using this screening approach. This limitation can be overcome by generating homozygous mutant follicle cell clones in heterozygous females using a system that induces site-specific mitotic recombination events. However, to date, eggs produced from egg chambers with complete follicle …  Lire la suite

Snider, Laurie M (Supervisor1)  Lire la suite

Echoes is an interactive composition for amplified chamber ensemble and computer. The entire research that led to this piece was based on the exploration of the evolution of the sound produced initially by the acoustic instruments and then interpreted by the computer. Why "Echoes"? As a sonic phenomenon the echo has several fairly distinct dimensions. These are commonly understood to include the following: the repetition of a sound by reflection of sound waves from a surface; any repetition or imitation of words, style or ideas; the sympathetic sound response; and, in music, a soft repetition of a phrase. Note that …  Lire la suite

The reliability analysis of telecommunication networks requires an estimate of the probability of failure of antenna-supporting structures. Lacking such estimates, the network planners tend to assume that the probability of failure of towers is negligible. On the other hand, reliability concepts implicit in the codes are not always compatible with those used in reliability analysis of the network, in particular, the implicit probabilities associated with partial load and resistance factors are obtained for idealized structural members and do not address the reliability of the structure as a system. Advances in structural reliability, combined with more extensive climatologic data, can be …  Lire la suite

Noemi Dahan Oliel (Supervisor2)  Lire la suite

Global IP traffic will continue to grow in the foreseeable future. Different applications are driving demand for increased capacity such as cloud based services, video streaming services, and big data.Since 2008, most Internet traffic has originated or terminated in datacenters. As a result, datacenters have experienced unprecedented traffic increases, where datacenter traffic will reach more than 20.6 zettabytes by 2021, i.e., 3-fold increase since 2016. In response to demands to support capacity increases, there are significant worldwide research and commercialization efforts that are being directed toward developing high speed intra- and inter-datacenter optical interconnects (DCIs). Different material platforms are used …  Lire la suite

Enantiomers are chiral molecules (i.e. they are mirror-images of each other). They have identical physical properties except for the rotation of polarized light. However their chemical properties are different when reacting with other chiral molecules. The majority of biological processes involve the reaction of two or more chiral molecules. There is therefore a strong interest coming from the pharmaceutical, food and agricultural industry for the separation of enantiomers. Separation methods such as chromatography exist but are generally expensive and limited in scale. Stereosynthesis often has prohibitive development and operating costs. For 10 to 15% of known enantiomeric systems, a conglomerate …  Lire la suite

Background: Alcohol consumption is common in individuals with diabetes. Heavy alcohol consumption in individuals with diabetes is associated with an increased risk of developing diabetes-related complications, including neuropathy, retinopathy, nephropathy, and coronary artery disease (CAD). Although heavy alcohol consumption is associated with complications, little is known about patterns of alcohol use among individuals with diabetes. Furthermore, heavy drinking is more common among individuals with certain psychiatric conditions, including major depressive disorder (MDD), bipolar disorder (BD), or generalized anxiety disorder (GAD), compared to the general population, and these disorders are often comorbid with diabetes. Therefore, individuals with diabetes may be at …  Lire la suite

As the plasma membrane of the cardiac muscle cell (sarcolemma) plays a major role in the cardiac physiology and homeostasis, the aim of this study is to identify using mass spectrometry (MS) and data base mining the integral and peripheral proteins that are making its composition and to uncover putative novel proteins and to ultimately reveal the differences in protein composition between the sarcolemma of control rat hearts and hearts submitted to ischemia and ischemia-reperfusion to find disease-specific markers. Toward this goal we have developed a new method to purify cardiac sarcolemma using an approach that avoids denaturing conditions and …  Lire la suite

Deckelbaum, Dan Leon Elazar (Supervisor2)  Lire la suite

Gracco, Vincent (Supervisor1)  Lire la suite

Gracco, Vincent (Supervisor1)  Lire la suite

Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease worldwide. While antiviral therapy achieves sustained virologic response (SVR) in over 95% of patients, metabolic dysfunction continues to influence liver fibrosis progression. Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is increasingly recognized as a significant factor in liver health, yet its impact on fibrosis in individuals with a history of HCV infection remains underexplored. This thesis is centered on a cross-sectional study investigating the association between MASLD and significant liver fibrosis in a cohort of 590 individuals with history of chronic HCV infection from two Canadian academic centres. …  Lire la suite

Harper, Samuel (Supervisor1)  Lire la suite

Normal breast growth and development depends on functional androgen:estrogen (A:E) balance. Androgen actions are mediated by the androgen receptor (AR), a DNA-binding, transcriptional-regulatory protein. Decreased AR transactivational. activity lowers A:E balance and may result in functional hyperestrogenicity: this could promote the pathogenesis of breast cancer (BC). The present study is the first to seek AR mutations in female BC. The length of the polymorphic CAG-repeat in exon 1 of the AR correlates inversely with the transactivational activity of the AR. Using 10% polyacrylamide gels, I found a significant (p < 0.0001) shift to greater CAG-repeat lengths in BC samples. This …  Lire la suite

The androgen receptor (AR) mediates the various actions of androgens and is responsible for the male reproductive system and male phenotype. AR mutations result in variable degrees of androgen insensitivity in XY individuals, ranging from complete to mild androgen insensitivity syndrome (AIS). Most of the AR-mutations are located in the ligand-binding-domain (LBD) and result in a complete or near complete loss of ligand binding. As revealed by several AR-LBD crystal structures, most of these mutations are located far from the bound-ligand, therefore their severe ligand-binding abnormalities must reflect more widespread LBD structural aberrations rather than local distortions at the mutated …  Lire la suite

La surveillance vidéo est devenue un sujet de recherche majeur récemment en raison du nombre croissant d'usages potentiels dans les espaces publics. En particulier, il y a une demande pour des applications de surveillance automatisées qui détectent différents types d'activités liées à la sécurité publique, comme dans les stations de métro. La surveillance vidéo automatisée est destinée à être utilisé comme une aide aux opérateurs humains en attirant leur attention à certains événements désignés d'intérêt. Cette thèse présente un système de surveillance vidéo en temps réel qui détecte une gamme d'activités dans une scène captée par une caméra vidéo couleur. …  Lire la suite

Background: Among women with chest pain and non-obstructive coronary arteries (NOCAD), approximately 50% have evidence of coronary microvascular dysfunction (CMD), which carries a heightened risk for long-term cardiovascular events. Current diagnostic tools used in the assessment of women with chest pain and NOCAD are invasive and have provided conflicting results. Oxygen sensitive magnetic resonance imaging (OS-CMR) using hyperventilation/breath-hold manoeuvres is an emerging technique that allows for a non-invasive assessment of myocardial oxygenation. We aimed to study the coronary vascular response to breathing manoeuvres as monitored by OS-CMR in women with chest pain and NOCAD. Methods: An interim analysis was performed …  Lire la suite

Mixed integer programming (MIP) provides an important modeling and decision support tool for a wide variety of real-life problems. Unfortunately, practical MIPs are large-scale in size and pose serious difficulties to the available solution methodology and software. This thesis presents a novel solution approach for large-scale mixed integer programming that integrates three bodies of research: interior point methods, decomposition techniques and branch-and-bound approaches. The combination of decomposition concepts and branch-and-bound is commonly known as branch-and-price, while the integration of decomposition concepts and interior point methods lead to the analytic centre cutting plane method (ACCPM). Unfortunately, the use of interior point …  Lire la suite

Enzyme changes in benign and malignant prostatic tissues were studied in an attempt to introduce new criteria of malignancy. Total lactate dehydrogenase activity was not significantly different between benign and malignant prostatic tissues. Lactate dehydrogenase isoenzyme pattern showed remarkable differences. The ratio of L.D.R.v/L.D.R.I > l was considered to be suggestive of malignancy and the results were analyzed according to this index. A high index was detected in 77.6% of malignant tissues and a low index in 86.1% of benign tissues. The change was not localized to the malignant focus but was generalized within the gland harbouring a focus of …  Lire la suite

The brain intraparenchymal microcirculation is regulated by various brain neuronal pathways, including the cholinergic and serotonergic systems. In this study, we determined the molecular identity, second messenger coupling, cellular distribution and/or vasomotor functions of the receptors for these two neurovascular systems in human and/or bovine brain microvasculature. Using reverse transcriptase-polymerase chain reaction (RT-PCR), we first identified heterogeneous muscarinic acetylcholine receptors (mAChRs) in microvessel and capillary fractions isolated from human cerebral cortex. Using a combination of RT-PCR and second messenger assays on human cerebromicrovascular cell cultures, we then identified functional M2 and M5 mAChRs in endothelial cells, the M1, M3 and …  Lire la suite

Les ressources spatiales seront inévitablement exploitées et commercialisées ; il est futile d'ignorer cette vérité évidente. La communauté internationale et les spécialistes ont longuement débattu pour déterminer si le traité sur l'espace impose une interdiction de l'exploitation des ressources spatiales ou si cette activité est possible en vertu du traité. Alors que les discussions se sont concentrées sur des questions telles que la définition d'un corps céleste et l'interdiction de l'exploitation aux seules activités gouvernementales, les développements technologiques actuels et les perspectives commerciales démontrent que la priorité doit être donnée à la réglementation appropriée de ces activités. Avec l'adoption par …  Lire la suite

To investigate the relation between amniotic fluid (amf) constituents and human fetal growth and birth weight (b.wt), amf was collected from 395 pregnant women undergoing routine amniocentesis at 14--16 weeks' gestation at the Royal Victoria (RVH), Jewish General (JGH), and St. Mary's (SMH) Hospitals. The fluid was analyzed for total protein, albumin, urea nitrogen, creatinine, uric acid, glucose, beta-hydroxybutyrate (betaHBA), and lactate. Maternal and neonatal data were collected from a questionnaire at the time of recruitment and from medical charts post-delivery. The mean b.wt in our population was 3409 +/- 552g. Birth weight differed significantly by infant gender, maternal height …  Lire la suite

Increasing interest has developed in the last few years in the study of plasma. For many years red blood cells have been studied, and techniques developed to make blood transfusion a safe procedure. The fluid part of a transfusion or blood plasma was considered to be useful, because, amongst other things, it contributed to blood volume, and certainly it was long thought to be harmless when taken from another member of the same species.  Lire la suite

"This thesis exemplifies the usage of non-parametric tests. In Chapter 1 we deal with the Kolmogorov-Smirnov goodness of fit test. We discuss the random variables of the type sup tF (x) -F(x)l, sup fF(X) -FN(X)j, and _00 < x <oot N J _00 < x <00 l ., where F(x) is a continuous distribution function and FN(x) is the empirical distribution function. Using these random variables we review confidence bands for the small and asymptotically large samples."@eng  Lire la suite

This work is intended to be an experimental contribution to the field of electrolytic conductance. Conductance work is a study of the behaviour of ions under an applied electric field. Since conductivity results can be readily obtained to a high degree of accuracy over wide concentration and temperature ranges, the data provide a basis for developing and testing theories of electrolytes. The objective of such theories is to predict the behaviour of electrolytes from a knowledge of certain properties, such as the dielectric constant and viscosity for the solvent, and the ionic charges and radii for the solute.  Lire la suite