McGill University Thèses et mémoires par auteur commençant par N

Lignos, Dimitrios (Internal/Cosupervisor2)  Read more

Dans le monde industrialisé, les accouchements prématurés représentent la première cause de mortalité infantile. Bien que plusieurs tocolitiques (ex. les médicaments qui bloquent les contractions) aient été développés au cours des dernières années, leur efficacité est limitée et leur toxicité souvent non-négligeable, expliquant le besoin de développer de nouveaux médicaments, moins dangereux et plus efficaces. De manière à pouvoir développer ce type de médicaments, une connaissance plus approfondie des mécanismes de signalisation responsable du déclenchement des contractions utérines est nécessaire. Le récepteur à prostaglandine F2α (PGF2α) ou FP joue un rôle clé en tant que médiateur de la contraction cellulaire …  Read more

In 1998 the Organization for Economic Cooperation and Development (the "OECD") commenced a campaign to eliminate harmful tax competition focusing on geographically mobile activities. The OECD targeted 35 jurisdictions and demanded that those nations amend their tax laws to remove the harmful features that provided more favorable tax treatment to geographically mobile capital than was available in some of its Member States. This thesis examines the international responsibility of the OECD and its Member States to determine whether their conduct in waging this campaign is in accordance with the international legal principles of state sovereignty and non-intervention. As an international …  Read more

Le développement de vaccins conventionnels implique la génération de réponses mémoires des cellules T et B qui fournissent une immunité protectrice pour prévenir la réinfection ou réduire la gravité d'une maladie. Le vaccin Bacille de Calmette-Guérin (BCG) est utilisé pour prévenir la tuberculose (TB), mais des données épidémiologiques ont démontré qu'il peut également offrir une protection contre d'autres agents pathogènes pulmonaires. La protection croisée induite par le BCG a été attribuée à la génération de réponses de la mémoire innée, appelée « immunité entraînée ». En fait, notre groupe a montré que la vaccination par le BCG génère une immunité …  Read more

Ouellet, Jean Albert (Internal/Supervisor)  Read more

Turbo codes are recommended in all leading third generation wireless standards. It is there-fore of interest to examine their performance in fading channels, specifically for the scenario where the channel state information is not available at the receiver. The scheme studied in this thesis is based on combined modeling of the convolutional code and the channel state uncertainties using a finite state machine. The combined model forms a supertrellis, whose structure is exploited in the SISO MAP (Soft Input Soft Output Maximum A Posterior) module. Properties of convolutional codes with respect to the reflection invariance are studied. It is shown …  Read more

The aim of this study was to: (a) identify risk factors for the development of venothromboembolism in a trauma population, (b) evaluate whether risk factors vary with increasing Injury Severity Score (ISS), and (c) assess the predictive ability of the Risk Assessment Profile for Thromboembolism (RAPT) in this trauma population. There were 7532 admissions for trauma between 1993 and 1998 to the Montreal General Hospital trauma center. A nested case-control design was used. Cases were defined as all patients with radiological evidence of either a deep venous thrombosis or pulmonary embolus during their admission. Controls were patients satisfying the same …  Read more

Jarvis, Eric (Internal/Supervisor)  Read more

Planar optical waveguides fabricated by proton-exchange and annealed proton-exchange in LiNbO$ sb3$ are investigated. The use of a Fermi function was found to accurately model the proton-exchange refractive index profile resulting in a better agreement between the measured effective mode indices and the computed dispersion curves compared to the conventional step-index profile. Numerical simulations of the nonlinear diffusion equation have shown that the proton-exchange process cannot be adequately described by the well established ion-exchange equations. A generalized Gaussian function was used to accurately model the refractive index profile in annealed proton-exchanged waveguides resulting in considerable improvements over previous work. Annealing …  Read more

BACKGROUND: In Canada, 60% of people aged 16 years and older are characterized as having low health literacy (HL) which impacts health outcomes and overall health status. Children of parents with low HL experience more emergency visits, brush their teeth less frequently, and are more likely to eat less nutritious food. In an attempt to overcome literacy issues and combat the barriers to information access affecting individuals with low HL, it has been advised that healthcare providers tailor the literacy requirements of their recommendations to the literacy levels of their patients through the dissemination of health videos. This can mitigate …  Read more

This study arises out of research on teacher beliefs and practice with regard to the social, political and economic conditions affecting English Language Learners (ELLS). Specifically, it examines how student-teachers in an introductory course to cross-cultural education at a state university in California reflect on their own beliefs about cultural, linguistic, racial, ethnic and socio-economic diversity; whether they examine the socio-political context of schooling language minority students; their beliefs about appropriate strategies and methodologies for ELLs; and if and how these beliefs have been influenced by the course. Forty-two student-teachers completed pre- and post-course questionnaires, and two completed interviews. The …  Read more

Isotope labelling technique in conjunction with pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) was utilized to conduct an in-depth investigation into the formation of lysine specific products in the Maillard reaction. Following the pyrolysis of the lysine/glucose models including their labelled counterparts for 20s at 250°C and extensive data analysis it was concluded that lysine can generate piperidine, a reactive secondary amine capable of undergoing Maillard type interactions. The formation of piperidine has been postulated to follow two pathways depending on whether lysine pyrolysis is conducted in the presence or absence of sugars. In the presence of glucose, lysine similar to asparagine …  Read more

Cairns, Robert (Supervisor)  Read more

Risk management is the identification, assessment, and prioritization of risks followed by coordinated and economical application of resources to minimize, monitor, and control the probability and/or impact of unfortunate events or to maximize the realization of opportunities. The strategies to manage risks usually include transferring the risk to another party, avoiding the risk, or reducing the negative effect or probability of the risk. Using any of these strategies in real life situations, either transferring the risk to another party in the form of outsourcing or reducing the probability of the risk from a deliberate attack from an adversary, may require …  Read more

Les plaques composites à renforts fibreux constituent en des ensembles de couches assemblées selon leur épaisseur de manière uni- ou multidirectionnelle afin d'obtenir des propriétiés de déformabilité ou de résistance optimales. Cette thèse se propose d'étudier les propriétiés élastiques effectives d'un composite à matrice de polyester renforcé par des fibres de carbone unidirectionnelle. Une simulation numérique est utilisée pour determiner les propriétiés élastiques equivalents dans l'hypothèse d'un comportement isotrope transverse au moyen d'un arrangement des fibres obtenu expérimentalement. Les estimation de ces constates élastiques obtenue par voie numérique sont comparées avec plusieurs estimations théoriques basées sur l'hypothèse d'un arrangement régulier …  Read more

La structure du génome 3D est une organisation très complexe à l'intérieur du noyau. Les interactions génomiques qui jouent un rôle important dans le développement cellulaire sont organisées à travers la structure du génome 3D et le repliement chromosomique. Les facteurs de transcription ont un impact important sur ces interactions. Pour comprendre et prédire comment ils se localisent dans la structure du génome, de nombreuses méthodes ont déjà été proposées. Cependant, aucun d'entre eux n'est complet et l'interprétation exacte des facteurs de transcription dans la structure de l'ADN 3D n'est pas entièrement comprise. La compréhension des modèles de probabilité devrait …  Read more

Le muscle squelettique contribue de manière significative à plusieurs fonctions corporelles. Il joue un rôle central dans le métabolisme du corps entier et il est le site principal pour l'élimination du glucose stimulée par l'insuline. La résistance à l'insuline dans le muscle squelettique est considérée comme un facteur déterminant qui mène à l'apparition du diabète de type 2 (DT2). Le muscle squelettique est également connu pour sa capacité à se régénérer après une blessure suivant un processus appelé myogenèse. La myogenèse aberrante peut entraîner de nombreux troubles musculaires, y compris différents types de dystrophies. L'identification et la caractérisation complète des …  Read more

• Dans l’apprentissage automatique, les mécanismes d’attention améliorent les modèles en identifiant les parties saillantes des données d’éntrée, ce qui améliore les performances dans divers domaines. Cette thèse explore la détection d’attention stricte dans deux tâches de vision clés :la reconnaissance d’activités humaines (HAR) et l’apprentissage avec peu d’exemples (few-shot learning), en abordant les défis liés à l’interprétabilité et à l’efficacité des données. Dans le domaine de la HAR, la pertinence des articulations du corps humain et des séquences vidéo varie selon l’activité, tandis que les méthodes existantes traitent souvent toutes les articulations et les séquences comme étant également importantes. …  Read more

L'une des caractéristiques les plus intrigantes du parasite protozoaire Trypanosoma brucei, est sa manière distincte de produire de l'énergie lors des différents stades de son cycle de vie. Dans l'hôte mammifère, les trypanosomes génèrent de l'énergie par glycolyse dans les glycosomes, tandis que dans l'insecte vecteur, ils génèrent plutôt leur énergie par phosphorylation oxydative dans les mitochondries. Le control de l'expression génique tout au long de leur cycle de vie s'avère donc crucial à leur survie. L'ARNm mitochondrial subie un processus de modifications post-transcriptionnelles unique grâce à des insertions et des délétions du nucléotide uridine via ARN guide; ce qui …  Read more

Hayward, Vincent (Supervisor)  Read more

De nombreux incidents liés à des problèmes de fonctionnement de moteurs d'avions ont été observés ces dernières années, tous caractérisés par l'extinction du moteur ou une perte soudaine de sa puissance. Ces incidents à haute altitude pourraient être causés par des cristaux de glace qui, de par leur trajectoire balistique, entrent directement dans le coeur du moteur sans être déviés par la force centrifuge vers le pontage, comme pour les gouttelettes d'eau. Les cristaux peuvent alors fondre lorsqu'ils rencontrent des températures plus élevées dans le moteur ou lorsqu'ils heurtent une surface chaude. Une telle surface humide pourrait devenir un noyau …  Read more

DNA methylation is an epigenetic modification that is essential for germline and embryo development. DNA methylation establishment occurs in the germline in a gender and site specific manner through the action of DNA cytosine-5-methyltransferase (DNMT) enzymes. Spermatozoa have been shown to have a unique configuration of DNA methylation as compared to somatic cells. Germline DNA methylation may also depend on the availability of methyl donors provided by the folate pathway through the action of 5,10-methylenetetrahydrofolate reductase (MTHFR). Absence of MTHFR has been associated with methylation loss in mature sperm as well as decreased male fertility. This thesis presents new data …  Read more

Reorganization of the intermediate filament (IF) network during axonal regeneration is accompanied by changes in the expression of various IF proteins. An increase in expression of the neuronal IF subunit gefiltin in goldfish retinal ganglion cells (RGCs) has been linked to the unique ability of the goldfish optic nerve to regenerate following injury. Evidence suggests that the optic tectum may regulate the expression of gefiltin during regeneration. The goal of this thesis was to determine the function of the tectum in the regulation of gefiltin mRNA expression during optic fiber regeneration in the goldfish. It was found that gefiltin mRNA …  Read more

Considerable investigation has been carried out in an effort to develop a satisfactory procedure to augment the blood supply to the heart. The stimulus in this work has been great due to the high mortality and morbidity resulting from diseases of the coronary arteries. [...] Since medical therapy does not alter or diminish the progress of the underlying changes in the vessels, there is a need for surgical therapeutic measures. In eighty percent of cases coronary artery disease is not immediately fatal when first diagnosed; thus, surgical therapy may be employed to modify or prevent further progression of the disease …  Read more

The sporadic form of Alzheimer’s disease (AD) is a multifactorial disease influenced by a multitude of factors. Among the most important factors are genetics and studies suggest that AD is highly heritable. Despite recent advances in discovering loci underlying this heritability, known loci only account for about a third of the genetic variance. Thus, the majority is still to be identified; an important process, as this can contribute to the identification of disease-causing mechanisms that in turn can lead to the development of potential drugs. As there is still no cure for AD, such new treatment options are sorely needed. …  Read more

This exploratory study seeks to develop theoretical insight into positive institutional work via a qualitative inquiry into the practices that constitute and sustain organizational engagement in social purpose organizations. Synthesizing the emerging field of Positive Organizational Scholarship (POS) (Cameron, Dutton et al., 2003), I define 'positive' as a quality that reflects a state of intrinsic subjective fulfillment situated in a broader extrinsic framework of social, moral, and/or spiritual meaningfulness. The study focuses on organizational engagement as a particularly rich exemplar of the kinds of positive phenomena taken up by POS scholars. Based on existing empirical work (Kahn, 1990; Nakamura and …  Read more

In many countries around the world, municipal sewage and industrial wastewaters are typically treated, or sometimes only partially treated, prior to their discharge into surface waters. A major anionic surfactant, Linear Alkyl benzene Sulfonate (LAS), and a degraded product of a non-ionic surfactant, Nonylphenol (NP), are frequently found in municipal wastewaters. When wastewater containing such surfactants and their degraded products is used for irrigation, it can have an effect on the sorption/desorption and movement of pesticides in soils. Therefore, a lysimeter study was conducted, in summer 2004, to assess the effect of LAS and NP on the movement of agricultural …  Read more

La présence de récepteurs couplés aux protéines G (RCPG) au noyau cellulaire n'est pas universelle et il a été suggéré que ces récepteurs nucléaires possèdent des fonctions de transcription de gènes, tandis que les récepteurs au niveau de la membrane plasmique semblent plutôt induire des effets aigus indépendants de la transcription de gènes. Le récepteur activé par protéase 2 (PAR-2) fait partie de la famille des RCPG. PAR-2 au noyau a été observée dans divers tissus cellulaires. L'origine des RCPG au noyau et les mécanismes menant à cette localisation ne sont pas connus. En utilisant PAR-2 comme modèle, le but …  Read more

This study seeks to explore the conditions under which producer cartels organized by primary producing countries to increase real external purchasing power (income terms of trade) can most effectively achieve their objectives. To this effect, conventional cartel theory is expanded so as to include the impact of the major institutional factors, with emphasis on centre-periphery (North-South) relationships, the roles played by governments of producing and consuming countries, by transnational enterprises as well as the particular conditions of supply and demand of various commodities. This framework is applied to bauxite, coffee and sugar industries, because each presents unique characteristics. As a …  Read more

Szpunar, Jerzy A. (Internal/Cosupervisor2)  Read more

Telomerase is a ribonucleoprotein that maintains telomere. It is activated in greater than 85% of human neoplasms. Traditionally, reactivation of telomerase during tumorigenesis was thought to be required solely to impart an indefinite lifespan. Recently, however, several studies have suggested that telomerase may contribute to tumorigenesis via an additional mechanism that is independent of its role in telomere lengthening. We sought to identify the region(s) of hTERT that contribute to this non-classical role of telomerase. We proposed to identify such regions by their ability to impart a tumorigenic phenotype in ALT cells transduced with activated Ras. Also, we attempted to …  Read more

L'isolateur de fondation et l'amortisseur visqueux liquide sont des dispositifs de protection couramment utilisés dans les structures de génie civil. Cependant, en raison de l'incertitude du mouvement du sol, du comportement non linéaire de la structure et de la variation de ses caractéristiques dynamiques (c. - à - D. rigidité effective et rapport d'amortissement) dans chaque nouvelle conception, la conception optimale de ces dispositifs reste une tâche itérative fastidieuse. La question de l'optimisation de la conception devient plus difficile pour les systèmes de ponts à réponses multiples, car il y a souvent des possibilités conflictuelles de dommages entre plusieurs éléments …  Read more

Laminar structure is a distinctive feature of cerebral cortex which comprises 6 layers, in which each layer is characterized by distinct cellular organization, specific inputs and projection targets. Anatomical circuitry across laminae has been well-studied, and previous studies have shown laminar-dependence of neural responses, suggesting that sensory information is processed in a laminar-dependent manner. However, the functional circuitry across laminae related to the underlying mechanism of laminar processing remains largely unexplored. This project is to explore functional connectivity measured with spiking activity across laminae, and test the hypothesis that functional connections triggered by first-order stimuli and second-order stimuli share great …  Read more

This research serves to answer the following basic question: Are potential toxic effects of hemoglobin solutions due to hemoglobin itself? Homologous and heterologous stroma-free hemoglobin and polyhemoglobin were investigated for their effects on complement activation, blood coagulation, platelet aggregation, blood cell counts, plasma electrolytes, proteins and enzymes in rats. A modified Mayer's method for testing whole complement hemolytic activity (CH$ sb{50}$) was developed. C$ sb3$ and C$ sb{ rm 3a}$ were also measured. Purified homologous or heterologous stroma-free hemoglobin or polyhemoglobin did not cause complement activation when incubated with rat plasma or when infused into rats. In addition, blood coagulation …  Read more

One of the major challenges in designing optimizing compilers, especially for scientific computation, is to take advantage of the parallelism in loops in order to obtain maximum speedup on parallel computer architectures. Optimal loop scheduling is therefore one of the most important topics studied by many computer scientists. However how to allocate minimum number of registers to support optimal loop scheduling for parallel architectures is less understood. In this thesis, we propose a simultaneous scheduling and register allocation approach for a parallelizing compiler, which will find one among all the time-optimal periodic schedules that uses minimum amount of registers. We …  Read more

Cette thèse présentera nos recherches théoriquessur les propriétés quantiques de transport électroniquedes jonctions de transport moléculaire. Cette analyse a été effectuéeà l'aide de méthodes ab initio atomiques qui sont validesdans les régimes non-linéaire et hors-équilibre.L'objectif est de rechercher non seulement une compréhensionqualitative des données expérimentales mais aussi quantitative. Les deux questions les plus importantesquant au travail théorique en électronique moléculaire sont:(i) quel est le bon modèle atomique pour simuler les dispositifsexpérimentaux? (ii) comment déterminer avec précisionles propriétés de transport quantique sans l'utilisation deparamètres phénoménologiques?Nos recherches sont centrées sur ces questions. Nous avonssystématiquement calculéles structures atomiques de jonctions moléculaires en effectuantla …  Read more

This study offers an interpretation of Joseph Maréchal's (1878-1944) five-volume work, Le Point de départ de la métaphysique (1923-1944). Broadly conceived as a historical investigation ranging from Greek philosophy through to German Idealism, the work offers an interpretation and critical response to Immanuel Kant (1724-1804) by means of reinterpreting the thought of Thomas Aquinas (1225-1274). The present work proposes analogy to be the guiding thread of Maréchal's work. To the numerous antinomies that characterize the history of western thought, Maréchal offers a solution by means of dynamism, the movement of passive entities towards actualization. Particularly in its epistemological form, this …  Read more

Garth Green (Supervisor1)  Read more

The incidence of melanoma worldwide has been increasing steadily in recent years with an associated rise in mortality rates. If detected early, melanoma lesions can be surgically removed with wide excisional margins resulting in high cure rates. However, as the melanoma invades the deep layers of the skin at the primary site and subsequently metastasizes to the regional and distant nodes, the prognosis for the patient becomes progressively worse. As the melanocytic lesion progresses from a benign nevus to a highly malignant metastatic melanoma, it undergoes changes in protein expression which may be relevant to melanoma development. Among the proteins …  Read more

Bartlett-Esquilant, Gillian (Supervisor1)  Read more

Neutron stars in mass-transferring binaries accrete hydrogen and helium rich matter from their companions. Unstable nuclear burning of this matter results in Type I X-ray bursts every few hours to days. Theoretical models propose three regimes of unstable burning on neutron star surfaces and also define the critical accretion rate above which the neutron star burns fuel stably without bursting. Currently, the theoretical value for this stability boundary is comparable to the Eddington limit whereas the observational limit is estimated to 0.3 m˙Edd. In this dissertation, we examine the boundary between stable and unstable thermonuclear burning at the surface of …  Read more

De nombreux modèles climatiques simulent que dans l'Arctique, la transition entre la glace de mer perpétuelle et saisonnière ne se fait pas graduellement. Au contraire, elle se fait par des périodes de déclins rapides qui sont causées par des pulses de chaleur océanique qui s'infiltrent dans l'océan Arctique et causent plus d'eau ouverte. L'eau Atlantique qui entre l'Arctique par les mers continentales (Barents et Eurasienne) a le plus grand impact sur l'évolution temporelle de la superficie de la glace de mer parce que l'eau plus chaude peut interagir avec la glace de mer avant de plonger a des profondeurs ou …  Read more

Cette thèse examine la figure de l’intellectuel dans le cinéma hindi, en s’intéressant à sa fonction allégorique au sein des récits du développement et de la justice sociale. J’accorde une attention particulière aux principes esthétiques et à la structure narrative de quatre films s’échelonnant des années 1970 aux années 2010 : Manthan (1976), Swades (2004), Court (2014) et Newton (2017). En m’appuyant sur la théorie des intellectuels d’Antonio Gramsci et en l’étendant par l’analyse cinématographique, j’examine comment la logique esthétique de ces films et le star-text de l’intellectuel filmique influent sur la construction esthétique de la figure allégorique. Dans Manthan, …  Read more

OBJECTIF: Cette étude avait pour but d’examiner l'effet des changements du profil respiratoire et des volumes inspiratoires finaux (VFI) dynamiques sur l'activation neurale du diaphragme crural (EMGDIA) et de certains muscles inspiratoires extradiaphragmatiques, y compris le muscle sterno-cléido-mastoïdien (EMGSCM), les scalènes (EMGSCA) et les muscles intercostaux externes (EMGINT).MÉTHODES : Douze adultes en bonne santé âgés de 25.1±1.6 ans (moyenne±SEM) ont effectué une série d'essais respiratoires de 30 secondes à une ventilation constante (V'E) correspondant à 15% de leur ventilation volontaire maximale tout en (i) modifiant le schéma respiratoire à un VFI constant et (ii) modifiant le VFI à un schéma …  Read more

Rabbi Joseph Bekhor Shor is a Torah commentator and a Tosafist from the twelfth century. Only a single copy of his commentary exists. This might suggests that it was not much in demand, and is confirmed by the fact that it was not published until the modern era. Nonetheless, his commentary attracted later commentators among the Tosafists in the field of Torah exegesis. Bekhor Shor's commentary demonstrates various types of linguistic features of Bible interpretation, such as, grammar, etymology, semantics, and syntax. It also deals with the style and some literary features of the Bible. Each feature presented in this …  Read more