McGill University Thèses et mémoires par auteur commençant par P

Au fur et à mesure que la fabrication additive (FA) évolue, le besoin d’une méthode rapide et efficace qui puisse déterminer comment celle-ci devrait s’appliquer à la conception du produit s’accroit. Auparavant, ces méthodes se mettaient au point naturellement et se transmettaient sous forme de connaissances tacites. Toutefois, tenant compte de l’avancement rapide des technologies de FA, il faut que l’identification des pièces qui seraient admissibles à la FA, tout comme l’acquisition d’un meilleur aper çu de la valeur qu’elles pourraient ajouter à un produit, soient modélisées de fa çon objective et transférable. Ce projet développe un cadre visant la …  Lire la suite

Multi-wavelength laser sources have attracted much interest in the last decade as new photonic technologies have enabled the realization of such sources with much improved characteristics. Tunable continuous-wave multi-wavelength fiber lasers may now offer, for example, the ability to tune the wavelength spacing between the lasing lines and, also at times, the possibility to control the individual output peak powers. The more flexible and low-cost solutions benefiting from higher optical spectrum bandwidths also attract the most interest for future applications. These lasers find clients in so many fields such as optical test and measurement, optical communications, sensing, and processing like …  Lire la suite

In this thesis, we explore the development of methods for efficient continual learning, to enable the sequential acquisition of knowledge by artificial intelligence (AI) systems as they adapt to new information over time. In the first chapters, we investigate approaches to address challenges posed by rehearsal-based methods in overcoming catastrophic forgetting, a major obstacle faced by deep neural networks when learning sequentially. We propose a Maximally Interfered Retrieval (MIR) method to optimize the efficiency of the replay step, which retrieves samples from the replay buffer whose prediction will be the most impacted by the foreseen parameter update on the newly …  Lire la suite

In a screening survey for a particular disease, suppose that results from one or more imperfect diagnostic tests are available. Using a Bayesian approach, methods for simultaneous inferences about the population prevalence of the disease and the characteristic parameters of the diagnostic tests are developed. Marginal posterior densities of all parameters are estimated using the Gibbs sampler, a Markov Chain Monte Carlo technique. The methods are applied to data from Kampuchean refugees who arrived in Montreal, Canada, during the years 1982-1983, to estimate the prevalence of Strongyloides infection in this population, as well as the test properties of two diagnostic …  Lire la suite

Tardif, Jean Claude (Supervisor2)  Lire la suite

Adipose tissue is an important contributor to energy homeostasis and the discovery that adipose tissue produces a number of hormones involved in regulating energy storage and energy utilization has been a topical area of research. Acylation stimulating protein (ASP/C3adesArg) is an adipose tissue derived hormone that stimulates fatty acid uptake and storage in adipocytes. ASP stimulates triglyceride (TG) synthesis via its receptor, C5L2. C5L2 also binds C5a, an anaphylactic protein structurally similar to ASP, yet its function as an active receptor for C5a is still under debate. However, in adipocytes ASP affects TG synthesis via increased diacylglycerol acyltransferase activity, glucose …  Lire la suite

Les invasions d'espèces modifient les écosystèmes naturels en perturbant les communautés indigènes et en modifiant les fonctions de l'écosystème, incluent la productivité primaire et le cycle des éléments nutritifs. Les poissons et écrevisses non-indigènes peuvent avoir des impacts négatifs substantiels, à la fois directs et indirects, sur les communautés récipiendaires. Cependant, les tentatives de développer des modèles prédictifs largement applicables de l'impact ont été obstruées par la contexte-dépendance – la variance spatiale et temporelle générée par l'influence des conditions abiotiques et biotiques locales. Dans ma thèse, je fais l'investigation des facteurs biotiques et abiotiques qui affectent les impacts directs et …  Lire la suite

A sophisticated and high tech form of state-to-foreign population diplomacy based on the use of the latest communication technologies has developed rapidly in recent years and has acquired an increasingly important position within a significant number of foreign affairs systems. Pioneered by the heavyweights of the international stage, the phenomenon has spread rapidly to secondary powers and is progressively extending itself to varying degrees to all states around the globe. This thesis grapples with the enigma raised by the brisk re-emergence of this foreign policy concentration by attempting to understand the reasons behind both the quantitative increase in public diplomacy …  Lire la suite

À mesure que les conditions écologiques changent à travers le monde, les espèces déplacent leurs aires de répartition géographique afin de suivre l'habitat dont elles ont besoin. En tant qu'ectothermes, les poissons dépendent fortement de leur environnement pour réguler leurs processus physiologiques, et de nombreuses études ont déjà montré que l'augmentation de la température de l'eau peut avoir plusieurs effets négatifs sur la physiologie des poissons. Certaines espèces de poissons présentent une capacité d'acclimatation thermique, ce qui peut leur permettre de persister dans leurs habitats actuels face au réchauffement des eaux. Malgré cela, des changements de répartition par contraction et …  Lire la suite

Methylenetetrahydrofolate reductase (MTHFR), an important enzyme in folate metabolism, mediates the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate which serves as the carbon donor for the conversion of homocysteine to methionine. It is also inhibited by S-adenosylmethionine which has shown to be actively demethylated to form S-adenosylhomocysteine, which is hydrolysed to homocysteine. MTHFR deficiency exhibits well-documented clinical and biochemical symptoms. The human MTHFR cDNA was isolated by Goyette et al (1994), and fifteen mutations have been identified at this locus. An animal model would prove to be useful for designing therapeutic approaches for understanding the pathogenesis of this genetic disease at the …  Lire la suite

Mobile applications provide services that can benefit various sectors of the society. It is imperative that the realization of mobile applications be well-planned and based on standards. The interplay of Extensible Markup Language (XML)-based technologies, software engineering principles, and "best practices" formalized as patterns provides such a systematic approach. This thesis formulates a rigorous classification of mobile application patterns into four categories: architecture, process, product, and usage. To express the patterns in a universal manner, an XML-based pattern notation, the Mobile Application Patterns Markup Language (MAPML), is introduced. Based on a requirements analysis and design description, the specification of MAPML …  Lire la suite

BLK has 43% sequence homology to BIK and an identical BH3 domain, a region that is critical for its proapoptotic activity, making it the strongest candidate mouse ortholog. In addition, the gene structures of these two proteins are similar in functional organization. BLK and BIK activate apoptosis in similar fashion in both human and mouse cell lines, dependent on the presence of a functional BH3 domain and active caspases. BLK, like BIK, is very unstable and can be stabilized by addition of pan caspase inhibitor, zVAD-fmk. In contrast to BIK, BLK is not upregulated by p53 at the RNA or …  Lire la suite

Antibodirs raised against rat thyroglobulin were labeled with the enzyme horseradish peroxidase, when sections of rat were placed in contact with the labeled antibodies, the staining for peroxidase revealed the sites of binding of the antibodies to the sections. In another series, the antibodies were labeled with radioactive 125I-iodide and tho sites of binding detected by radioautoqraphy. Light and electron microscopic study by either procedure revealed that the luminal colloid was the most active site of bindinq. Within follicular cel1s, the following organelles were labeled: rough endoplasmic reticulum, Golgi apparatus, apical vesicles and colloid droplets. The controls for specificity, sensitivity …  Lire la suite

Anthropologists have long recognized the central role of social systems in enhancing environmental sustainability, but few have attempted to accurately assess the conditions under which traditional social institutions can equitably and effectively manage access to natural resources for the purposes of their use and conservation. By failing to look closely at how resource management practices are shaped both by local-level cultural institutions and the political and economic forces of government policies and markets, anthropologists have compounded the confusion surrounding the functions and capacities of traditional resource management institutions. This dissertation examines the connections between institutional and economic incentives and resource …  Lire la suite

Gene targeting is a process of recombinational exchange between a foreign molecule of DNA and its homologous chromosomal counterpart whereby the cellular machinery involved in homologous recombination accomplishes sequence exchange. The widespread use of gene targeting as a basic research and/or therapeutic tool has been precluded by its inherent inefficiency. Although many studies have reported improved gene targeting efficacy via manipulation of homologous recombination-associated proteins, reports examining the underlying molecular mechanisms of gene targeting are scant. Improvement in our understanding of these molecular mechanisms will undoubtedly lead to advancements in the study of genetic disease, and perhaps to the development …  Lire la suite

Glutamate binding studies on membrane preparations from unselected and ivermectin-selected strains of the parasitic nematode of ruminants, Haemonchus contortus, indicated a single class of saturable, high affinity binding sites which are sensitive to ivermectin and exhibit different pharmacological characteristics from any known mammalian glutamate receptor. These studies showed that H. contortus larvae possess substantially more glutamate binding sites with lower affinity than adults. Moreover, selection with ivermectin was associated with an increase in the number of glutamate binding sites in adults and an increase in the affinity for glutamate binding in larvae. When investigating the effects of ivermectin on glutamate …  Lire la suite

The share of renewable energy resources for electricity generation is growing with the deepening of the penetration of intermittent, weather-dependent sources, which is leading to a transformation of demand and supply patterns. In order to compensate this variability in the power balance, a promising alternative is bioenergy. Traditionally, biogas digesters have been designed to provide a continuous supply of biogas. This implies that electricity generation from biogas is no more dispatchable than other non-dispatchable renewable sources like wind and solar power. Nonetheless, there are ways to make bioenergy capable to modulate its power output to provide grid support services (e.g., …  Lire la suite

International investment law and international human rights law were often considered as two distinct species of international law. Doctrinal studies and international jurisprudence have however started to reveal the different interactions that may exist between them. The negative impacts that foreign direct investments play on the human rights of the host state's population are, moreover, a reality that cannot be hidden today. Based on these interactions between foreign investments and human rights, this study aims at looking at how abuses or the risk of abuses, committed by foreign investors in the context of their investment project can have major consequences …  Lire la suite

Le but principal de ce mémoire de maîtrise est la construction de séquences de fonctions propres de l'opérateur laplacien sur le disque qui se concentrent sur des anneaux variant en largeur dans la limite de grandes valeurs propres. Nous établissons une base d'Hilbert pour les fonctions propres en utilisant une technique appelée la séparation de variables en coordonnées polaires. Par cette méthode, nous résolvons deux équations différentielles: celle angulaire est triviale, alors que l'équation radialle demande l'étude des fonctions de Bessel de la première et deuxième espèce. Utilisant les conditions limites, nous démontrons dans le théorème 1 qu'uniquement les fonctions …  Lire la suite

Schwarz, Bernhard (Supervisor1)  Lire la suite

Potato requires high levels of nitrogen fertilizer. Up to now in Quebec, no nitrogen fertilizer recommendation has been based on nitrogen availability in the soil, even those soil nitrogen testing is available. The objectives of this study were: (1) to determine the relation between soil nitrate-N content, nitrogen fertilization and potato yield; and (2) to determine the time and the sampling depth of soil most appropriate to predict potato yields and response to nitrogen fertilizer under Quebec conditions. Soil samples were taken at two depths at planting and at hilling time in 28 sites fertilized at four levels of nitrogen. …  Lire la suite

In many engineering applications, assumptions regarding the most appropriate boundary conditions for a structure are typically made to simplify the analytical or numerical procedure being employed. In most situations, the engineer or analyst is well justified in assuming one of the classical boundary conditions such as pinned, fixed, or free. However, certain applications require that the boundary conditions be well characterized so that the system’s dynamic response is correctly modeled. Heat exchanger and nuclear fuel assembly tubes are a category of such structures, where thermal, hydraulic, and mechanical loadings during operation can lead to unwanted structural vibrations.In this thesis a …  Lire la suite

Brittain, W. H. (Supervisor)  Lire la suite

Burgess, Donald (Supervisor)  Lire la suite

Berlo, Kim (Supervisor1)  Lire la suite

It was natural that Tennyson should be interested in the many social and political problems that forced themselves upon the notice of all thinking men of his day, but more than most writers he felt called upon to use his influence toward the solving of these problems. He usually tried to keep close to his own times, adapting classical and medieval material to the needs of contemporary society and, taken as a whole, his 'works present a complete panorama of nineteenth century life. Thus he stands out from among the other poets and writers of his time as peculiarly the …  Lire la suite

Le développement de la thérapie de resynchronisation cardiaque (TRC) était fondamental pour améliorer le traitement des patients souffrant d'insuffisance cardiaque (IC) et de bloc électrique intracardiaque. Malgré toute cette importance, jusqu'à 30% des patients restent étiquetés comme non-répondeurs. De nouveaux algorithmes automatiques ont été développés pour permettre la fusion des fronts d'onde triples: intrinsèque, ventriculaire droit (VD) et ventriculaire gauche (VG). Nous avons cherché à évaluer si la programmation avec l'un de ces nouveaux algorithmes est associée à la durée complexe QRS (QRSd) et à l'amélioration des paramètres échocardiographiques par rapport à la programmation de routine TRC chez les patients …  Lire la suite

In 1935, H. L. Hollingworth wrote that, "among the numerous familiar fears of mankind none is more common than 'stage fright' (22, p. 173). Yet, despite its ubiquitous nature, the phenomenon is only poorly understood. The broad aim of the present study is to extend this understanding in the conviction that "stage fright" is of interest in its own right and that the concept is of theoretical value for psychology, particularly that aspect of social psychology concerned with group phenomena.  Lire la suite

This study is part of a program of research on the nature of "stage fright". The analysis to date has suggested that stage fright is an instance of a more general phenomenon of "social influence" where people in interaction are conceptualized as "actors" presenting themselves before "audiences". [...]  Lire la suite

Economic geography scholarship rests on the assumption that work has a well-defined and fixed location. Existing data and traditional methods for capturing the location of work have not yet been able to grasp the increasingly dynamic spatiality of knowledge work that other disciplines — like Mobilities and Management and Organizational Studies — have been discussing for some time. These disciplines suggest that as a result of greater worker mobility, flexibility and digitization work has been extending beyond the official, well-defined workplace. If this is the case, the concepts that underpin our understanding of where work takes place need to be …  Lire la suite

Omanovic, Sasha (Supervisor2)  Lire la suite

This thesis compares growth and behaviour of domestic sows and piglets in confined pens versus get-away pens (where sows could leave their fitters at will), to ask whether parent-offspring conflict occurs, whether it increases with offspring age, whether it involves offspring access to the udder, and whether it affects animal production or welfare. Parent-offspring conflict occurs in domestic pigs: piglets of Confined sows suckled more and ate less solid food but grew at the same rate as piglets from Get-away sows, indicating they obtained more milk. Confined sows lost more weight than Get-away sows and returned to oestrus later, indicating …  Lire la suite

In order to describe the ontogeny of solid food consumption by pigs and determine its influence on weight gain, before and after an abrupt weaning at 4 weeks of age, individual feed consumption was measured using a technique that combined load cells and video images. Feed consumption varied greatly both between and within litters. Within litters, consumption was positively correlated with birth weight, and with early weight gains. This suggests that greater feed intake was typical of larger and more mature pigs rather than reflecting compensation for poor milk intake by smaller litter-mates. Within-litter differences in weight gain during the …  Lire la suite

Pharmacokinetic studies of acute oral doses of d,1-methadone (25 mg kg('-1)) were carried out on adult non-pregnant, pregnant and lactating female guinea pigs, quantitating the blood plasma methadone levels by gas-liquid chromatography following solvent extraction. The mean (beta) t(, 1/2) of methadone in these animals were 7.7 h, 14.6 h and 11.6 h, respectively. Differences in plasma t(, 1/2) were attributable to difference in drug metabolism. Repeated administration of methadone neither significantly altered the (beta) t(, 1/2) nor had any significant influence on the in vitro hepatic microsomal monooxygenases (nitroanisole O-demethylase (OD) and aniline hydroxylase (AH)). In contrast, methadone treatment …  Lire la suite

Caspase-6 is a cysteinyl aspartic-specific protease that is activated during pre-clinical stages of Alzheimer disease (AD) and correlates negatively with cognitive performance. We propose that Caspase-6 inhibition may combat the age-dependent cognitive decline in AD. Several Caspase-6 inhibitors have been developed, yet none have proven to be strong enough candidates to pursue clinical trials. To address this, two novel Caspase-6 inhibitors were studied. Methylene blue is a Tau aggregation inhibitor that has been tested in phase III clinical trials against AD. Mass spectrometric analysis demonstrates that methylene blue oxidizes Caspase-6's catalytic cysteine, which represents a novel inhibitory post-translational modification. Moreover, …  Lire la suite

This research emerged from the belief that merely economic explanations of rent seeking were too narrow and an interdisciplinary approach was needed to understand historical structural factors that contribute to particularistic exchanges. Rent-seeking and particularistic ties are almost always explained from a strictly neoclassical perspective which tend to be reductionist approaches that fail to explain why some states will be rent-seeking while others will not. Moreover, other frameworks that analyze state-civil society interaction do so without taking into account particularistic state-civil society interaction. Thus, there is a need to explain such particularistic ties in a comparative institutional framework. My dissertation …  Lire la suite

Introduction: Il y a nécessité d'avoir accès à un questionnaire de qualité de vie qui pourrait offrir les avantages d'un questionnaire générique et ceux d'un questionnaire spécifique à la MPOC. Objectif: Finaliser l'élaboration d'un nouveau questionnaire hybride le 'McGill COPD Quality of Life Questionnaire' (éléments spécifiques à la maladie complémentés d'éléments génériques issus du SF-36) et évaluer ses propriétés psychométriques (fiabilité, validité, réponse au changement) chez les sujets atteint d'une MPOC. [...]  Lire la suite

Les œuvres littéraires peuvent être étudiées suivant des méthodes variées, selon le choix que l'on fasse de mettre l'emphase sur des aspects idéologiques, thématiques ou stylistiques. Nous avons choisi dans cette étude sur la poésie russe de nous concentrer sur ce dernier aspect. Ce travail traite du plus important des poètes du Romantisme russe, Alexandre Pouchkine, et porte principalement sur une comparaison du vocabulaire employé dans les premiers poèmes de la période du Lycée (1814 - 1817) et dans le poeme "Eugène Onéguine" (1823- 1831).  Lire la suite

In spite of the growing interest of Russian and Western scholars in Sergei Dovlatov and his art, his place in Russian literature has not yet been clearly defined. His position as a writer in Russia in the 1960s and early 70s was ambiguous due to his opposition to the traditional Soviet canon and rejection by the current literary establishment. However, he later gained recognition and popularity as an emigre writer in the United States. The concept of 'marginality' colours his biography and art, for his life itself was a succession of marginal experiences and marginality is the key topic of …  Lire la suite

Urokinase plasminogen activator (uPA) promotes tumor invasion and metastasis in several malignancies including breast and prostate cancer. High levels of uPA are associated with invasive and metastatic characteristics of cancer. I examined the differential regulation of uPA expression by DNA methylation in normal, hormone responsive and hormone insensitive human breast and prostate cancer cell lines. Lack of uPA expression in normal and hormone responsive cells is due to methylation of uPA promoter. Treatment of these cells with a demethylating agent resulted in induction of uPA, higher invasive capacity of the cells, and significant increase in tumor volume. These studies demonstrated …  Lire la suite

Deterministic and stochastic hybrid optimal control problems are studied for systems where autonomous and controlled state jumps are allowed at the switching instants and, in addition to running costs, switching between discrete states incurs costs. Features of special interest in this work are the possibility of state space dimension change, and existence of low dimensional switching manifolds. In other words, the hybrid state space is considered as the direct product of a set of discrete state components with finite cardinality and a set of Euclidean spaces whose dimensions depend upon the discrete state components; and Euclidean spaces contain switching manifolds …  Lire la suite

Since antibiotics have been added to animal feed for decades, foodanimals and their wastes constitute a reservoir of antibiotic-resistant bacteria. Atthe Swine Complex of McGill University, the addition of antibiotics to swine feedfor subtherapeutic applications has been discontinued since January 2007. Theobjective of this work was to assess the prevalence and short-term evolution ofantibiotic resistance among bacterial populations in swine production 2.5 yearsafter this discontinuation. Feces from ten healthy pigs (6 males and 4 females)born at the Swine Complex of McGill from the same sow and administered feedwithout antibiotics were sampled during suckling, weanling, growing andfinishing. The percentage of chlortetracycline-resistant …  Lire la suite

La plupart des aérosols atmosphériques sont trop petits pour être vus à l'œil nu, mais leur impact sur la santé et le climat est immense. L'Organisation mondiale de la santé et le Groupe d'experts intergouvernemental sur l'évolution du climat désignent ainsi l'étude détaillée des aérosols atmosphériques comme étant une priorité de recherche. Pour comprendre l'impact des aérosols sur le climat mondial, la santé des populations et la chimie de l'atmosphère, nous devons comprendre les caractéristiques physiques et chimiques des aérosols. Il s'agit notamment de la distributions des tailles d’aérosols dans l'espace tridimensionnel (3D), de la dynamique des aérosols, ainsi que …  Lire la suite

Background: Patients undergoing major cardiac surgery face a significant risk of rehospitalization, often due to complications related to dysregulated immune responses and ineffective cardiac repair. Despite direct implications in cardiovascular health and immunity, the role of the gut microbiome in cardiac surgery recovery remains largely unexplored. In a surgical setting, gut microbiota are vulnerable to extrinsic stressors that may promote microbial disorder. This study explores the post-surgical gut microbiome and its potential to exacerbate systemic inflammation and promote adverse cardiac remodeling, with a focus on sex-specific responses. Further, it examines the therapeutic potential of perioperative high resistant starch (RS) supplementation …  Lire la suite

The study of the problems of economic development, with reference to the so-called underdeveloped countries, has become a popular subject in recent years. The literature dealing with various aspects of economic development is multiplying rapidly. [...]  Lire la suite