McGill University Thèses et mémoires par auteur commençant par N

Ces dernières années ont connu le développement et l'utilisation de satellites hautement manœuvrables capables d'entreprendre des opérations autonomes de rendez-vous et de proximité en orbites terrestre basse et géosynchrone. Cette technologie a entrainé l'émergence d'une menace pour la sécurité découlant d'approches étroites imprévues et non coordonnées. En réponse à cette menace et à d'autres activités spatiales dont le double usage est inhérent, la présente thèse analyse la légalité de zones unilatéralement déclarées de protection et de sécurité autour d'objets spatiaux critiques. Premièrement, ce travail illustre la menace émergente à travers l'analyse de l'interaction entre un satellite militaire Russe et un …  Read more

"The Laurentian system, which forms the basement on which all the newer sedimentary strats of the earth's crust have been laid down, is exposed in many widely separated parts of the world: as for instance in Africa, South America, India and Scandinavia; but the greatest exposure of this system is found in Canada. In fact it received the name Laurentian from Sir William Logan, owing to the fact, that for some four hundred miles, it is continuously exposed along the north shore of the Gulf of St. L awrence, forming the so-called Laurentide mountains. ...  Read more

Dans les disciplines de l'ingénierie et de la conception architecturale, de nombreux problèmes d'optimisation multi-objectifs ont des objectifs, des variables de décision ainsi que des contraintes qui changent de façon dynamique au cours du processus d'optimisation. Pour résoudre ces problèmes, les algorithmes évolutifs multi-objectifs dynamiques (DMOEA) fournissent un moyen efficace et efficient. Par contre, la majorité des recherches dans ce domaine ont porté sur des problèmes théoriques dans lesquels l'utilisateur a un rôle limité et les changements au problème dépendent du temps (c'est-à-dire, lorsque les fonctions de l'objectif ont le temps comme variable, en plus de ces autres paramètres d'entrée). …  Read more

Harrison, F. (Supervisors)  Read more

Groleau, Danielle (Supervisor2)  Read more

Lockhead, W. (Supervisors)  Read more

Fifty years ago, the title of a monograph announcing serious study of the thought of Algernon Charles Swinburne as revealed by his poetry would probably have provoked a simle in even the most tolerant reader. Young Swinburne had shot like a meteor through the calmness of the Victorian sky. His genius as a lyrist was everywhere conceded but, save in the minds of his own particular circle of friends, the London reveller of a few years previous was granted little credit for an earnest thought in connection with the problems of social, political or religious philosophy. [...]  Read more

Contexte: La sclérose systémique (SSc), une maladie auto-immune rare et chronique, a un impact profond sur le bien-être physique et psychologique. La résilience, la capacité à maintenir une santé mentale malgré des circonstances défavorables, reste peu étudiée pour la SSc. Cette thèse présente 2 études de la cohorte SPIN (Scleroderma Patient-centered Intervention Network). L'étude 1 a examiné la validité, la fiabilité et le fonctionnement différentiel des versions anglaise et française de l'échelle de résilience Connor-Davidson à 10 énoncés (CD-RISC-10). L'étude 2 a étudié la résilience en lien avec la gravité de la maladie et la santé mentale.Méthodes: L'étude 1 a …  Read more

L'activation du stress du réticulum endoplasmique (ER), notamment la réponse au stress des protéines mal repliées (UPR) et la dégradation associée au réticulum endoplasmique (ERAD), engendre des lésions dans certaines maladies glomérulaires rénales. Il a déjà été prouvé que la Protein-tyrosine phosphatase 1B (PTP1B) régule positivement la branche IRE1α (inositol requiring-1α) d'UPR. Nous proposons que PTP1B est un modulateur important de la lésion glomérulaire provoquée par l'activation du système du complément, aidé par la régulation de la signalisation de IRE1α, incluant l'activation de c-Jun N-terminal kinase et ERAD. Pour tester cette hypothèse, nous avons utilisé des cellules fibroblastes de souris …  Read more

Les étudiants universitaires avec un handicap physique et des conditions chroniques ne respectent pas les directives recommandées en matière d’activité physique. L’exécution des techniques de changement de comportement (TCC) (c.-à-d. la capacité d’utiliser des TCC dans la vie quotidienne après une intervention) émerge comme un facteur déterminant de l’efficacité des interventions en matière d’activité physique, mais est souvent négligée pendant la mise en œuvre et l’évaluation des interventions. Pour améliorer l’exécution des TCC, une intervention d’activité physique qui déplace l’attention de guider des participants à travers des TCC (par exemple, aider un participant à fixer un objectif) vers l’entrainement des …  Read more

ABSTRACTBackground: Initiation of breastfeeding within the first hour of life can prevent 22% of infant mortality. The unique composition of human milk makes breastfeeding among the most determining factors in a newborn’s health and development. Besides its nutritional and bioactive components, human milk has its own diverse microbiome. Several factors were found to modulate these bacterial communities, including maternal factors and breastfeeding practices such as exclusive, predominant, and mixed feeding. However, the impact of initiation of breastfeeding within the first hour postpartum on the human milk microbiome has not previously been explored.Objectives: To investigate the impact of initiation of breastfeeding …  Read more

About 40% of human pregnancies are unsuccessful and many of these are thought to be genetically normal. Our hypothesis is that decidual NK cells in abortion prone pregnancies produce IFN-gamma which primes macrophages. These primed macrophages are then triggered by a second signal to become the major effectors in early embryo resorption. Analysis of individual implantation sites was performed at day 9 of pregnancy to determine the cytokine profile of these NK cells and if NK cells selectively infiltrate the decidua of embryos that will undergo resorption. Use of a pan-NK cell marker (DX5) allowed labeling of decidual NK cells …  Read more

Four microbial lipases were examined to test a proposed substrate model based on the relative size of the substituents on the stereogenic carbon of $ alpha$-substituted carboxylic acids (Fig. 5). Literature and our results for the kinetic resolution of carboxylic acids with the lipases from Candida rugosa, Aspergillus niger, Mucor meihei and Pseudomonas cepacia showed that sterics alone do not account for enzymatic enantioselectivity. In the course of this work, it was found that the lipase from Aspergillus niger showed appreciable enantioselectivity (E = 19 $ pm$ 3 at pH 7/10 mM phosphate buffer) in the hydrolysis of methyl pipecolinate. …  Read more

This research examines some of the ways to design a digital control system with particular reference to the control of yaw plane dynamics of an air-to-air missile model. Specific attention is paid to compare two methods of global digital re-design of validated analogue closed loop control system. These two methods are the multi-input multi-output (MIMO) Plant Input Mapping (PIM) method and multi-loop PIM method. The thesis will first show how a specific class of closed loop MIMO feedback systems with a single-input multi-output (SIMO) plant can be re-structured as multi-loop control systems, which includes the closed loop missile control system. …  Read more

Goldsmith, Peter (Supervisor)  Read more

Haiku from Tashme est une collection de courtes pièces totalisant 16 minutes composées pour chœur SATB et flute. Elles mettent en musique six haïkus écrits par Sukeo « Sam » Sameshima lorsqu’il fut interné de force au camp Tashme durant la Seconde Guerre mondiale, suivant le sort commun des Canadiens d’origine japonaise. Haiku from Tashme vise à sensibiliser sur ce chapitre sombre et presque souvent oublié de l’histoire canadienne en reconstruisant les paysages sonores associés avec les souvenirs de l’auteur durant son temps à Tashme. Sur le plan pratique, ceci est effectué à travers la représentation musicale des images poétiques …  Read more

Programmed cell death (apoptosis) is a fundamental process in multicellular organisms. The human proto-oncogene bcl-2 functions to suppress apoptosis and promote cell survival. It is the-most studied apoptotic regulator, yet the mechanism of action of this protein remains elusive. We have identified p28Bap31 as a Bcl-2 associating protein which also interacts with Bcl-XL. p28Bap31 is a polytopic integral membrane protein which resides primarily in the endoplasmic reticulum with an N lumen-Ccyto orientation. This orientation exposes the COOH-terminal leucine zipper overlapping with a weak death effector domain, flanked on either side by caspase cleavage sites, to the cytosol. In the absence …  Read more

In order to elucidate the effect of chemical kinetics on the dynamic structure of a detonation, an investigation is carried out by means of high-resolution numerical simulations of the reactive Euler equations. The chemical description ranges, with increasing complexity, from simplified single-step reaction kinetics to complex models with detailed chemical reaction rates. To illustrate the unsteady dynamics of the detonation structure and its dependence on chemical kinetics, a one-dimensional pulsating detonation with one-step kinetics has been investigated. Different nonlinear dynamics of the pulsating front are observed by varying the global temperature sensitivity of the chemical process. Numerical results have suggested …  Read more

The problem of direct initiation of detonations has been investigated numerically by using a more realistic chemical kinetics scheme. The chemical kinetics model is based on a three-step chain-branching reaction consists sequentially of a chain-initiation and a chain-branching step, followed by a temperature independent chain-termination. The steady ZND structure using the 3-step chemical kinetics model is compared with that based on the standard single-step Arrhenius rate model. An unsteady computation has also been performed to determine whether the solution from steady-state analysis can be approached asymptotically from a transient development. The three regimes of direct initiation have been numerically simulated …  Read more

This dissertation consists of four articles that contribute to the sociology of migration and demographic research on families and fertility. It examines family-related attitudes across immigrant generations, focusing on gender roles and fertility ideals. It finds that attitudes toward gender roles are more influenced by acculturation, while attitudes toward ideal family size are less susceptible to such pressures. Second, it distinguishes between attitudes and behavior, showing that fertility norms in the parental country of origin have little effect on fertility behavior in the second generation.The first empirical chapter uses the European Social Survey to examine gender role attitudes among Muslim …  Read more

A 1/12 scale tank was constructed to physically simulate the metallurgical skimming process in order to gain a better insight of the skimming of fluid slag from copper anode furnaces. 1-decanol and water were used to represent the slag and the underlying liquid metal respectively. It was observed that slag skimming was comprised of two steps, a transportation step to carry slag to the skimming lip, and a removal step to move the slag across the lip. The efficiency of the transportation by bath surface circulation was strongly affected by the method of creation of the surface movement. Submerged gas …  Read more

The application of a 2D hydraulic-habitat model, River2D, to simulate flows and fish habitat areas in a reach of the Nicolet River (Quebec, Canada) containing two sets of double-wing rock current deflectors to enhance fish habitat was examined. Depth-averaged velocity in the reach was determined using one or two measurement points in the vertical under the assumption that the profile was logarithmic; however, the presence of boulders and obstructions disturbed the profile, making it difficult to characterize using only two measurement points. The sensitivity of the simulation results to roughness characterization, topographic scale, mesh refinement, and boundary conditions was evaluated. …  Read more

Background: Studies have suggested that human papillomavirus (HPV) vaccine-induced humoral immune responses protect against subsequent HPV infections and consequently reduce the risk of HPV-related abnormalities. However, the dynamics of naturally acquired HPV seroreactivity and its impact on HPV acquisition among unvaccinated couples remain poorly understood. Objectives: Manuscript 1 introduces sample-specific modeling approaches to explore the heterogeneity of HPV seroreactivity in unvaccinated sexually active females. Manuscript 2 examines the association between naturally acquired HPV seroreactivity and HPV transmission among heterosexual couples. Methods: The HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) cohort study collected serum L1 antibody titer, genital …  Read more

The concurrent biodegradation of polycyclic aromatic hydrocarbons (PAHs) and transformation of heavy metals by redox reactions has been demonstrated by several studies. The mechanisms and reactions that result in heavy metal transformation in such systems is, however, poorly understood. This study explored the role of metabolic intermediates, metabolic end-products, and microbial chelators generated by a PAH-degrading microorganism, Pseudomonas putida ATCC 17484, in reducing or transforming Cr(VI). This study investigates the role of 1,2-naphthoquinone to serve as potential redox mediators in the reduction of Cr(VI) to Cr(III). Laboratory experiments were conducted to evaluate the extent of Cr(VI) reduction in the presence …  Read more

Many people with Multiple Sclerosis (MS) are forced to exit the workforce prematurely due to the unpredictable nature of their disease. Several studies have attempted but failed to explain the majority of the variation seen in employment status in people with MS. Moreover, many of the regression models developed were too simplistic in their representation of work or are outdated as they were conducted in the 1980's. MS-employment literature suggests that work is affected by several interrelated variables. The objective of this study is to estimate the direct and indirect effects of personal characteristics and body function impairments in people …  Read more

A new approach to underground excavation design at INCO's Manitoba Division was undertaken by incorporating ground and support monitoring, and numerical modelling into an empirical framework. In the first phase of the study, a field measurement geomechanics guideline was developed for the Manitoba Division. Work in instrumentation led to the development of a new cable bolt monitoring device by INCO Ltd. and McGill University. This device has the ability to measure cable bolt performance reliably and at a low cost. As a result, a cost efficient and effective program is being implemented to monitor cable bolt layouts representatively. The second …  Read more

This study evaluates the life history responses of yellow perch to mass removal and the potential for population recovery. We removed approximately 94% of a perch population from Nepawin Lake, a 35 hectare oligotrophic lake in Algonquin Provincial Park, Ontario, as part of a study designed to enhance the recruitment success of brook trout. Several response variables were examined both before and after mass removal: (1) condition, which includes growth, diet and overall condition responses, and (2) reproduction, which includes size at maturity and fecundity. We examine the question of whether compensatory life history responses in the yellow perch will …  Read more

Geons are simple 3-D geometric primitives proposed by Biederman for object representation. The idea is to segment objects into an arrangement of simple geometric shapes. Objects represented by geons can be identified more easily since the many-to-one mapping of object recognition is reduced to the recognition of a small number of geons. In this project, a vision system is implemented for the search and recognition of geons. The vision system is composed of a colour camera and a laser range finder, and is mounted on a pan-tilt unit. The entire setup is mounted on a mobile robot. The task of …  Read more

Bernatsky, Sasha (Internal/Cosupervisor2)  Read more

The desire to obtain a perfect physical environment and a more satisfying way of life is typical of Western Civilization, since it possesses dynamic force and incorporates economic strife for progress. The Central Area of a city is generally considered as the focal point of both communal and commercial life. It is in this Central Area where the greatest concentration of human activities from all parts of the Metropolis exist. [...]  Read more

Atherosclerosis is a cardiovascular disease that is known to be the primary cause of heart attacks and strokes. The hard plaque that forms within the arteries can be vulnerable to rupture, causing thrombosis which can effectively obstruct the flow of blood. The identification of vulnerable plaque is directly related to the composition of the plaque itself. Current imaging methodologies do not sufficiently address the issues of identifying early stages of atherosclerosis, plaque composition and thus, lesion vulnerability. Photoacoustic imaging techniques used in conjunction with contrast enhancing nanomaterials have offered a novel approach to address these problems. This thesis presents a …  Read more

With technological advancements in data collection techniques allowing increasing amounts of contextual metadata to be appended to everyday image files, it has become a daunting task to effectively display such supplemental data alongside original image content without overloading users with information. I propose a unique approach to actively display geo-tagged image content that embeds the images in a navigable 3D environment in a way that makes explicit the geographical context and spatiotemporal relationships between the images. This approach enhances the viewer's comprehension of the image's context and content thus supporting my hypothesis that context extracted from metadata can enhance image …  Read more

This dissertation is a study of Shichan lun (Ten Topics on Birth), a widely disseminated medical treatise produced in the Northern Song dynasty (960-1127), around the early twelfth century. Shichan lun records how childbirth progressed and it also contains detailed descriptions of hand techniques deployed by women practitioners during birth complications. I examine its composition, incorporation into a larger work (in the thirteenth century), and redaction (ca. early to mid-sixteenth century). In Chapter One, I translate and analyze the earliest extant edition of Shichan lun, collected in Chen Ziming's Furen daquan liangfang (All Inclusive Good Prescriptions for Women, pub. 1238). …  Read more

Previously it had been shown that an extracellular nephrotoxin, from a Streptococcus pyogenes type 12 strain could induce acute glomerulonephritis in rabbits. The immunosuppressant azathioprine, a purine analog, was administered to the rabbits to see if altered immune response in the animals would affect the course of acute glomerulonephritis. Preliminary experiments were carried out to arrive at a suitable dosage of azathioprine. In a further experiment rabbits received both azathioprine and nephrotoxin. In these animals no kidney lesions developed but hypertension still occurred. Experiments were also conducted in efforts to increase the yield of the nephrotoxin, and to isolate the …  Read more

The effect of the extracellular, dialysable nephrotoxin produced by a group A type 12 streptococcus on the rabbit was studied critically for the similarities to human acute glomerulonephritis. Nephrotoxin-treated rabbits have been found to have renal changes upon light and electron microscopic observations. In the latter case, numerous "humps" and cellular proliferation and edema were evident in the glomeruli. No consistent glomerular deposition of autologous gamma globulin could be found by using immunofluorescence microscopy. No alterations in serum complement activity were noted. Chemical characterisation of purified nephrotoxin was performed by end-group analysis, ultraviolet, fluorometric and infrared spectroscopy and quantitative assays, …  Read more

The nature of protein-protein interactions was explored through the design of polypeptide ligands targeting specifically human a-thrombin. Design strategies ranged from isolation of binding fragments from natural proteins, conformational stabilization using structural scaffold, to bivalent linkage of library-selected components. The interaction of thrombin with a 28-residue polypeptide from the sixth-epidermal growth factor-like repeat of human thrombomodulin (hTM-EGF6) was characterized in solution by use of NMR spectroscopy. The thrombin-binding region was identified and the thrombin-bound structure of the binding region was determined. The thrombin-bound structure of this fragment of thrombomodulin was then used as a basis for the design of peptide …  Read more

Jung, In-Ho (Supervisor2)  Read more

Campylobacter species are among the most common foodborne bacteria responsible for gastrointestinal illnesses in humans. Campylobacter jejuni is a microaerophilic pathogen and naturally colonizes the intestinal tracts of various farm animals, including cattle, sheep, goats, pigs, and poultry. Human infections typically occur through the consumption of contaminated food or water. Although C. jejuni is highly sensitive to environmental stressors such as heat, cold, salinity, chemical treatments, and irradiation, conventional control strategies (e.g., heating food above 50°C) may not eliminate the pathogen. Instead, these treatments often leave behind sublethally injured but viable cells that can repair, proliferate, and potentially cause illness …  Read more