McGill University Thèses et mémoires par auteur commençant par Y

Zeitouni, Anthony G (Internal/Cosupervisor2)  Read more

Catering to the rising demand for clean and affordable solar energy, this thesis explores aqueous solution synthesis and thin-film fabrication of two important photovoltaic semi-conductors - TiO2 and CZTS - Cu2ZnSnS4. Firstly, nanocrystals of TiO2 were synthesized in a high-throughput production process in a continuous stirred-tank reactor (CSTR) using a dilute aqueous solution of TiCl4 as the feed. The process was conducted at a range of TiCl4 concentrations (0.1-1.0 M), temperatures (70-90 ◦C), and solution pH (2-6). Maintenance of relatively high solution pH 2-5 via continuous addition of NaOH prevented redissolution of the otherwise metastable anatase phase. Primary nanocrystals measuring …  Read more

This thesis deals with the social relations within two feminist-inspired housing co-operatives in Montreal by employing the analytical tool of social network from an interactionist perspective. The housing co-op milieu is a highly suitable terrain for reflections on feminist urban theory. 'Public' and 'private' space, identity and place, and 'community' and community development are central themes addressed in this study. Members of each co-op were interviewed using a semi-directed interview guide. Social interaction is analysed qualitatively and focuses on the content of exchanges between co-op residents and patterns of socialising. The study concludes with an analysis of spatial micropolitics in …  Read more

Naveen Eluru (Supervisor1)  Read more

Background: The diverse microbial community residing in our gut, termed the “gut microbiota”, is an ecosystem with multiple functions in human physiology, including nutrition, immune system development, and protection against enteric pathogens. Any alteration in this microbial composition (dysbiosis) can potentially influence diseases such as inflammatory bowel disease, cancer, and obesity. Prebiotics are non-digestible dietary fibers, which can be used to modulate the microbiota composition with beneficial outcomes for the host health. Indeed, complex glycans in our diet are an essential source of carbon for the gut microbiota, which collectively encodes the thousands of carbohydrate-active enzymes (CAZymes) necessary to metabolize …  Read more

Metrakos, Peter (Internal/Supervisor)  Read more

Fernandez, José Manuel (Internal/Cosupervisor2)  Read more

Rank one transformations provide a rich source of examples of maps which satisfy certain mixing properties. Using the way that they are constructed, Chacon proves that certain rank one transformations are weakly but not strongly mixing. We also study some of their spectral properties, showing that certain rank one transformations have singular or continuous spectrum, and that they all have simple spectrum. Next we look at the characterisation of mildly mixing transformations due to Furstenberg and Weiss. Finally we study uniformly Cesaro transformations, which are used in constructing rank one strongly mixing transformations.  Read more

Choksi, J. R. (Supervisor)  Read more

En raison du caractère urgent des missions effectuées par certains giravions, il est souvent impossible de soit retarder ou modifier la route du vol même sous des conditions météorologiques extrêmes. Par conséquent, le vol dans des conditions de givrage connues est en augmentation. Les giravions sont toutefois plus vulnérables au givrage que les avions en raison de leur faible altitude de vol et de leurs profils aérodynamiques minces. Le cumul de glace entraîne une augmentation plus importante du poids, de la traînée et du couple, affectant ainsi les performances, la dynamique et la stabilité du giravion.Alors que les méthodes CFD …  Read more

Les infrastructures en alliages métalliques, comme l’acier inoxydable, se dégradent et peuvent céder sous l’effet de divers facteurs mécaniques et électrochimiques, notamment la corrosion et la fissuration par fatigue. Par exemple, la durée de vie des turbines hydrauliques est souvent réduite en raison de l’interaction synergique entre la corrosion et la fatigue. La fissuration par fatigue, causée par des chargements cycliques mécaniques (c.-à-d. des déformations répétés), entraîne une déformation microstructurale à proximité de l’extrémité des fissures, influençant ainsi le comportement de la corrosion localisée. Malgré son importance, l’interaction entre corrosion et fatigue demeure peu étudiée. Cette thèse s’attaque à cette …  Read more

R.U., Yong  Read more

MacPherson, Hugh (Supervisor)  Read more

Phosphorus and nitrogen present in runoff from agricultural land is a primary freshwater pollution source in southern Quebec. The focus of this study was to optimize a constructed wetland for use as a best management practice and the specific aim was to determine if substrate type influences its phosphorus and nitrogen reduction capabilities. The pilot-scale constructed wetland site was located 3 km north of McGill's Macdonald campus in Ste-Anne-de-Bellevue, Quebec, Canada. Three tank replicates filled with sandy clay loam soil, and three with a sandy soil were planted with cattails (Typha latifolia L.) and reed canary grass (Phalaris arundinaceae L.). …  Read more

The hormones are of fundamental importance in correlating the metabolism of an organism as a whole by causing changes in the vital processes of its specific tissues. Malfunctioning of one or more of the endocrine mechanisms may result in profound disturbances in or even death to an animal. Administration of crystalline hormones or extracts of these highly active substances elicits effects which have been carefully determined. Such physiological responses are more or less transitory in nature tending to demonstrate that the hormones are rapidly transformed to inactive substances. Because of their marked physiological actions, a large volume of work has …  Read more

1. An apparatus was built to follow the decomposition of benzene-diazo-acetate in solution by measuring the pressure of the nitrogen evolved in a constant volume system - the evolution of air from solution occurred simultaneously due to an initial decrease in pressure to protect the system. One of two otherwise similar cells was fitted with electrodes for application of an electric field. 2. The rate of pressure increase for a concentration of 0.4 g. per 1. was greatly accelerated by an electric field of 3000 volts per cm. and 1.5 megacycles. The effect of the field decreased rapidly as the …  Read more

La fondation des relations entre l’Angleterre et l’Empire Ottoman dans la fin du 16e siècle a nécessité un échange des lettres royales pour conformer aux coutumes diplomatiques au début de la périod moderne. La correspondance royale entre Elizabeth I et ses homologues Murad III et Mehmed III, ainsi que Safiye Sultan, dans l’époque 1579 – 1600 a représenté une discontinuité de ces traditions épistolaires établies.Cette thèse explore comment et pourquoi la correspondence Anglo-Ottoman s’est conformée ou s’est distinguée des coutumes européennes et ottomans en forme, en langue, et en protocole. Un examen des lettres individuelles et le corps de toutes …  Read more

This thesis presents a fully abstract order-theoretic denotational semantics for networks of asynchronous real-time processes. The time-sensitive nature of the component processes allows them to compute functions which are not Scott continuous, nor even monotonic, on the domain of timed message streams ordered by the usual prefix relation. Because of the discontinuous behavior of the components, the characterization of networks containing nonmonotonic processes as fixed points of continuous functionals (the standard approach of denotational semantics, applied to untimed networks of monotonic processes by Kahn in 1974) has been a much-sought but unattained goal. This thesis shows how it can be …  Read more

Dagher, Alain (Supervisor1)  Read more

In response to an interest in evaluating school social work service, its approach and training as provided by the HcGill University School of Social Work, an attempt at developing and validating the School Social Work Q-Sort w~s made. This effort was seen as an initial step in working tmvards a 'teacher measure' to supplement objective outcome measures that may be used in the evaluation. The main aim was in developing an instrument for describing and evaluating the effort and impact of the Inter-Professional Collaborative Approach, through a reliable and relevant group of respondents. By enlisting the teachers' help in sorting …  Read more

The effect of phosphate functionality and dentin surface state on adhesion to dentin was investigated in a series of experiments. In all cases, variable effects were evaluated by measuring the strength of adhesion promoted by either of two priming agents, (PENTA, or DIPENTA), or their combination, to different surface conditions of dentin. The main difference between primers is the presence of a phosphate functionality in PENTA. These experiments demonstrated that the phosphate-containing primer promotes significantly greater adhesion compared to the non-phosphate containing primer for all surface states studied. They further showed that on demineralized dentin, strong adhesion for PENTA may …  Read more

Le ver parasite Dirofilaria immitis est responsable pour la dirofilariose chez le chien et constitue une menace zoonotique pour l’homme, constituant un problème majeur de santé publique. La transmission se produit par les piqûres de moustiques, et la prévention de la maladie repose principalement sur les lactones macrocycliques (LM) telles que l’ivermectine (IVM). Cependant, la prévalence croissante de la résistance aux LM compromet les efforts de lutte contre la maladie. Des études antérieures ont montré que les profils génétiques des isolats sensibles et résistants de D. immitis sont complètement différents. Bien que les changements génétiques soient liés à la résistance …  Read more

Orsat, Valérie (Supervisor2)  Read more

There is a debate on the exact relationship between capitalist development and democracy. Some maintain that there is a theoretical and empirical affinity between the two, while others have demonstrated that authoritarian regimes have been as able to accommodate capitalist development. A major part of this debate revolves around the economic elite's political preferences, which in some cases is perceived as championing democracy while in others, especially in cases of late-development, as supporting the rise of authoritarianism or, in the least, benefiting from the deficiencies of limited democracy. The shifting position of this elite therefore begs the following question: Is …  Read more

Rousseau, Jérôme (Supervisor)  Read more

The Ribonuclease H (RNase H) family of enzymes selectively degrades the RNA strand of DNA/RNA hybrids. Using a sense strand which contained the minimum natural RNA gap requirement, the kinetic rates of degradation of a series of heteroduplex substrates containing 2'F-ANA antisense oligonucleotides of variable flexibility were examined. Results from these studies implicate flexibility of the antisense oligonucleotides as a major requirements for RNase H catalytic efficiency. In addition to the above, physicochemical studies have revealed the thermal stabilities and relative conformations of these modified heteroduplexes under physiological conditions. All of the above findings offer further insights into the physical …  Read more

ABSTRACTBirth asphyxia remains a major global health issue and a significant cause of neonatal mortality and neurological morbidity. Birth asphyxia causes interruptions in the high cerebral demand for oxygen (hypoxia) and/or blood (ischemia) and may consequently lead to neonatal encephalopathy (NE). The current standard of care for NE is therapeutic hypothermia (TH), which provides neuroprotection by preventing further brain injury. This therapeutic approach has several major limitations including not being neurorestorative by repairing already occurred brain injury, expensive, not available in developing countries, and lastly doesn't confer neuroprotection to all newborns who receive it. There is a need to compliment …  Read more

Dans cette dissertation, nous avons introduit le concept d'hydrodynamique de 13 moments régularisés (R13) développé initialement par Struchtrup et Torrilhon dans le scénario non-relativiste. En adoptant une méthodologie similaire dans le cas relativiste, nous avons obtenu l'hydrodynamique R14 de deuxième ordre et de troisième ordre. Pour toutes les deux théories, une série d'analyses de stabilité et causalité linéaires a été effectuée sur les solutions des équations hydrodynamiques correspondents en supposant que les particules sont sans masse et que le nombre des particules ne se conserve pas. Cela est réalisé en décomposant les équations d'évolution linéarisées en composantes longitudinales et transversales, …  Read more

Ouellet, Jean Albert (Internal/Cosupervisor2)  Read more

Due to the anthropogenic activities, the increasing carbon dioxide concentration in the atmosphere is disturbing the natural equilibrium of the greenhouse gas, and causes the global temperature rise. In 1990, the CO2 emission from fossil fuel fired power plants contributed 30% of global emissions. In the same year, the cement industry contributed about 5% of the total. According to Kyoto Protocol, a tremendous effort is required to reduce the carbon dioxide emission. One potential technology in CO2 mitigation responses is the use of concrete products as carbon sink through the early age fast curing. The cement compounds C3S and C2S …  Read more

Marie-Josée Dumont (Supervisor2)  Read more

Les événements de la Place Tiananmen en 1989 a déclenché le processus durant lequel la société chinoise a évolué d'un soi-disant "haut modernisme" vers un vague "post-modernisme". Le but de cette thèse est d'examiner et d'évaluer la représentation des sexes dans l'écriture des intellectuels chinois mâles quand ils font face à l'évolution sociale mentionnée ci-dessus. L'auteur qui exemplifie bien le groupe d'intellectuels masculins chinois que j'ai choisi est Yu Hua, un des romanciers les plus importants et prolifiques de la Chine d'aujourd'hui. Bonne coïncidence, sa carrière d'écrivain qui couvre la période commençant au milieu des années 1980 jusqu'à maintenant, trace …  Read more

Plant Breeders' Rights (PBR) are a form of intellectual property rights enabling breeders of new plant varieties to have the exclusive right to produce and sell propagating material of their new plant varieties. The existence of effective property rights has been pointed to as a stimulus of increased R&D and productivity. Canada has had legislation to provide PBR protection for about two decades, and is considering further strengthening of the regulatory framework. However, there are few studies that have examined the effectiveness of the legislation on crop productivity. This thesis investigates the hypothesis that the adoption of wheat varieties qualifying …  Read more

The long time relaxation behavior of linear and long chain branched (LCB) metallocene polyethylene (mPE) is very important for understanding their flow properties. One linear and four LCB mPEs were studied in shear creep and recovery measurements. All the mPEs have similar molecular weight and molecular weight distribution but different levels of long chain branching. A technique was developed to eliminate the effect of non-ideal start-up at the beginning of creep experiment and the small residual stress that exists during the creep recovery period. It is found that the existence of long chain branching is responsible for the increasing of …  Read more

$B sp pm$ mesons are reconstructed through the decay chain $B sp pm to chi sb{c}K sp pm, chi sb{c} to J/ psi gamma,$ and $J/ psi to mu sp+ mu sp-.$ Using data taken at the Collider Detector at Fermilab in $ bar pp$ collisions at $ sqrt{s}$ = 1.8 TeV during the 1988/89 run, we have seen the signal of the $B sp pm$ mesons from this decay channel although the statistics still need to be improved. By Monte Carlo methods, we also conclude that it is possible to resolve the individual $ chi sb{c1}$ and $ chi …  Read more

Showan Nazhat (Supervisor1)  Read more

The crisis of the Liberal International Order (LIO) has been extensively studied. Although the reasons vary, the key boils down to discontent and losing support. Among the LIO's integral pillars, the economic sub-order, specifically the liberalized trade and finance regimes, are meant to support the order, but it seems to have fallen short of doing so. One troublesome symptom is the non-random, persistent global imbalances in terms of trade and current account imbalances. Surplus states tend to exhibit the traits of "winners": a strong industrial sector, better public service provisions, and higher R&D expenditures, vis-a-vis the deficit “loser” states. Unlike …  Read more

Neurodegenerative disorders associated with aging present as one of our society’s most significant challenges. Understanding the neural dynamics underlying these disorders have become increasingly important to develop treatment and prevention strategies. Previous work has shown that people spontaneously adopt either hippocampus-dependent spatial strategies or caudate nucleus-dependent response strategies when navigating. In the current study, we analyzed resting-state fMRI data collected from both spatial and response learners from two cohorts, one aged 24.39 ± 3.5 years old and the other 66.19 ± 4.2 years old. We examined differences in functional connectivity between spatial and response learners using three different analyses. First, …  Read more

La stratégie mondiale visant à parvenir à une économie industrielle agroalimentaire durable et circulaire, devra inclure l’utilisation de la biomasse forestière comme matière première pour en extraire des ingrédients fonctionnels naturels. L’érable, un important symbole reconnu du Canada, représente environ 3 % du total des arbres du Canada, et il produit chaque année une grande quantité de biomasse feuillue qui est considérée comme un déchet et, une fois éliminée, peux présenter certains problèmes environnementaux. Parmi les ingrédients fonctionnels d’origine végétale les plus populaires, les composés phénoliques connaissent une demande croissante de la part des secteurs alimentaire, nutraceutique, pharmaceutique et cosmétique. …  Read more

Philippe Campeau (Supervisor2)  Read more

I initially set out to identify the cap structure on the spliced leader RNA of Ciona intestinalis. During this investigation, I discovered a previously unobserved 53 nt transcript containing the spliced leader sequence. This transcript contained the usual metazoan spliced leader RNA cap, trimethylguanosine, while the canonical spliced leader RNA lacked this moiety, but likely contained a mP7PG cap. The cap structure of the trans-spliced troponin I mRNA matched that of the canonical spliced leader RNA, indicating that the canonical spliced leader RNA, not the 53 nt transcript, is the donor for troponin I. Further immunoprecipitation studies showed that both …  Read more

Quaternary glacial deposits have covered much of southern Ontario in till. Rivers incised into this cohesive sediment have been little studied. Land use change and climate change are increasing river flows leading to increased erosion. To determine the range of erosional resistance of tills, as well as the effects of weathering due to freeze-thaw cycles and wet-dry cycles, the erosion mechanisms and critical shear stress of glacial tills from two Ontario rivers, the Otonabee River in Peterborough, and Medway Creek in London, were studied. Till samples were collected at one in-stream location along the Otonabee River and at two locations …  Read more

The objective of this study was to evaluate the variability of growth curves of dairy heifers and estimate genetic parameters. 15066 records taken from birth until 26 months (808 days) on 2754 heifers of Quebec were considered. The pedigree file comprised 10123 animals. The Mixed procedure of SAS with ordinary polynomials was used for simple phenotypic analyses, fitting fixed linear, quadratic and cubic regressions of body weight (in kilograms) on age (in months) as well as random intercept, and random linear and quadratic regressions for each animal. The Wombat program (Meyer, 2007), with Legendre polynomials was used to estimate the …  Read more