McGill University Thèses et mémoires par auteur commençant par Y

An approximate method for predicting the degree of translational-torsional coupling of mixed-bent type multi-storey building structures subject to dynamic loading is presented. The method uses the parametric approach and is based on the generalized representation of asymmetric wall-frame structures by shear-flexure, torsion-warping cantilevers. It is applicable to structures consisting of any combinations of walls and frames that are uniform with height. Simple methods for predicting the uncoupled translational-torsional period ratio and the equivalent eccentricity, which require a knowledge of only the preliminary design information, are developed. The actual coupled period ratio can then be estimated in terms of these two …  Read more

Le mouvement relatif d'une image sur la rétine dû au mouvement actif de l'observateur dans son environnement, souvent appelé mouvement de parallaxe, fournit une importante source d'informations pour la segmentation et la perception de la profondeur. Deux types de contours peuvent résulter d'un tel mouvement : les contours parallèles à la direction du mouvement génèrent un mouvement de cisaillement, alors que les contours orthogonaux à la direction du mouvement créent une occlusion dynamique. Cette dissertation étudie le rôle et l'importance de ces contours définis par le mouvement de parallaxe, et comment les mouvements de la tête et des yeux les …  Read more

Traditionally, human visual sensitivity changes in luminance and chromatic contrast, collectively termed photometric changes, have been measured using simple laboratory stimuli such as disks or gratings. The results of experiments using such stimuli have generally been accounted for in terms of relatively low-level mechanisms such as quasi-linear filters in the visual cortex. Therefore, one might not expect the higher-order structure of natural scenes to influence sensitivity to uniform photometric changes. On the other hand, it is believed that the visual system is optimized for analyzing visual information in natural scenes, which leads to the alternative hypothesis that the unique structure …  Read more

Cette thèse propose une approche numérique afin de conduire l'analyse modale non-lisse d'un système prototype simplifié sous la forme d'une barre élastique finie dont le mouvement est unilatéralement restreint par un obstacle rigide sur la frontière. Mathématiquement, le problème se réduit à trouver des solutions périodiques à l'équation d'onde autonome avec un mécanisme de commutation entre les conditions aux limites de Dirichlet et Neumann, décrivant précisément la condition de non-pénétration.Les expressions analytiques de tels modes de vibration non-lisses existent seulement pour des hypothèses simplificatrices limitantes. Dans un cadre plus général, les techniques numériques doivent être exploitées. Des études antérieures ont …  Read more

In dealing with the Pauline concept of the church as the body of Christ (s oma Christou), numerous New Testament scholars and others have tried to come to grips with a fundamental but yet unresolved issue--the nature of the relationship between Christ via his own body and the church as body. Embedded in much of the discussion is the implicit assumption that s oma Christou as ecclesiological language does point to Christ's once crucified but now risen body in some direct way. This thesis examines that basic assumption in the light of the 18 ecclesiological references to soma found in …  Read more

Samples of fac and mer carbonyltrihydridotris(triphenylphosphine)iridium (III) were prepared and fully characterized by i.r., ('1)H and ('31)P n.m.r. spectroscopies. Isomeric interconversion at 25(DEGREES) C was demonstrated. The rates of isomerization and hydrogen loss from each isomer were independently measured. The similarity of these rates strongly supports a mechanism by which isomerization occurs through the oxidative addition and reductive elimination of molecular hydrogen. The results of deuterium labelling experiments were consistent with the isomerization mechanism, and further suggest that either trans-oxidative addition of hydrogen or intramolecular hydride interchange in the mer isomer may occur. Various partially deuterated analogues of the fac …  Read more

The property of rotating the plane of polarlzation of light, which certain crystals and liquids possess, is remarkable in that the physical theories of the phenomenon are numerous, not concordant and incomplete. Among them may be mentioned mathematical discussions by J. J. Thompson [...] in each or which expressions are found for rotatory power in terms of other characteristics of the active substance, generally of the charge and positions of the particles which make up the asymmetric molecule, but even assuming these to be known ina particular case the relations which are obtained are too oomplex to permit numerical evaluation. …  Read more

Whitby, G. (Supervisors)  Read more

The objective of this research was to examine the effects of plant sterols and glucomannan on lipid profiles, plasma plant sterol levels and glycemic control in mildly hypercholesterolemic subjects. Thirteen type 2 diabetic and sixteen non-diabetic individuals participated in a randomized crossover trial consisting of 4 phases, of 21 days each. During the study period, subjects were supplemented with plant sterols and/or glucomannan. Overall reductions of total cholesterol and low-density lipoprotein (LDL) cholesterol concentrations were greater after consumption of plant sterols and glucomannan compared to plant sterol or glucomannan supplementation alone. Plasma lathosterol levels, indicators of cholesterol biosynthesis, were decreased …  Read more

Mitchell, Claudia A. (Supervisor1)  Read more

This thesis examines the identity of the students at the Montreal Hoshuko and the factors that affect the way in which they identify themselves as Japanese, drawing upon a framework of political economy and concepts of globalization and transnationalism. It also explores how Japanese identity is changing in this globalized world. The fieldwork demonstrates that the identity of the Hoshuko students is somewhat commoditized based on Japanese popular culture such as Pokemon. It suggests that increasing communication and contact with external forces has changed and will further change the way Japanese people understand their own culture, identity, and themselves. It …  Read more

New classes of monomers containing heterocyclic groups have been prepared in good yield from readily available compounds. The heterocyclic groups were phthalazinone, quirnazolinone, benzopyrenequinone and acridone. Bisphthalazinones, such as oxy-7-bis(1,2-dihydro-4-phenylphthalazinone) were reacted with a series of activated aryl halides to give high molecular weight novel poly(phthalazinone)s in a one-step reaction involving the formation of a N-C bond. A series of novel quinazolinone containing monomers synthesized for nucleophilic aromatic displacement polymerization reactions, bisphenols and activated difluorides, were unstable under the polymerization conditions. Only low molecular weight oligomers were formed. Two new quinazolinone diamines, oxy-bis(1,4-phenylene)-bis[3-(4-aminophenyl)-1-oxo-quinazolin-2-yl] and 2-(4-aminophenyl)-3-amino-4-quinazolinone were synthesized. They did not …  Read more

This dissertation is manuscript-based. It contains an introduction, a literature review, a conclusion along with the four research papers that constitute its core. The four substantive papers reexamine the sources of earnings differences by race and immigration status in Canada. I address two major methodological issues in the relevant literature: the measurement of experience and the modeling of the relations between the factors known to influence earnings. Data from Statistics Canada's Workplace and Employee Survey (WES) was analyzed. The first two papers examine biases in the estimates of wage disparities due to error in the measurement of experience. They do …  Read more

La motilité cellulaire est essentielle pour de nombreux évènements physiologiques tels que la morphogenèse embryonnaire et la réparation tissulaire. Une migration aberrante des cellules peut entraîner divers processus pathologiques, notamment des métastases cancéreuses. Ainsi, l’étude des changements physiques associés à la migration cellulaire est importante pour notre compréhension de nombreux processus biologiques. Une transformation biologique concrète ayant un impact considérable sur la physiologie et la pathologie est la transition épithélio-mésenchymateuse (TEM), un processus par lequel les cellules épithéliales perdent leur adhésion cellule-cellule et deviennent des cellules mésenchymateuses plus migratrices et potentiellement invasives. Quoique nécessaire pour diverses fonctions biologiques, ce mécanisme …  Read more

La migration cellulaire est un processus hautement intégré et fondamental à de nombreuses fonctions biologiques passant par le développement, la réponse immunitaire et la cicatrisation des plaies, ainsi que la métastase dans le cancer. À fin de migrer, les cellules doivent générer et transduire des forces de traction à leur environnement. Cependant, aucune technologie à ce jour a fourni une solution à haut débit pour mesurer ces forces de traction.Je présente ici une nouvelle méthode analytique pour mesurer les forces contractiles cellulaires utilisant des plaques de culture multi-puits et robustes: En utilisant un format de plaque à 96 puits, des …  Read more

Richards, John Brent (Supervisor1)  Read more

The phenomenon of photochemical initiation of gaseous detonation waves has been experimentally and theoretically investigated. In the experiments, the flash photolysis technique has been employed and the initiation phenomenon has been directly observed through schlieren photography, while in the theoretical phase, the non-steady reacting flow-field of a photochemically ignited gas mixture has been numerically analyzed. The results conclusively show that the direct detonation initiation can be generated by an intense ultra-violet radiation, and it is shown that the initiation mechanism is mainly attributed to the rapid shock wave amplification occurring in a non-uniformly photo-dissociating gas mixture. It was found that …  Read more

The effect of free radical pre-sensitization on the transition from deflagration to detonation (DDT) in a combustible gas has been studied experimentally. Sensitization was achieved before spark ignition and DDT by illuminating a quiescent mixture of hydrogen and chlorine with a weak ultraviolet source. The arrival time of the reaction front was monitored by means of discretely located optical sensors along the length of the detonation tube. While no observable changes are produced during the early stages of the flame acceleration process, it is found that radical seeding promotes the onset of detonation through a reduction in run-up length and …  Read more

Franco, Eduardo (Supervisor)  Read more

Atomic decomposition of audio describes sound as a linear combination of elementary waveforms (atoms) from which high-quality coding, source separation, and signal transformation can be achieved. When the desired output is produced using only a few atoms, the decomposition is sparse. Existing atomic decomposition algorithms rely on computing many correlations between a time-signal and a redundant dictionary of atoms causing them to become increasingly memory/computationally intensive as the signal length grows and/or the atoms become more complex.In this thesis we approach atomic decomposition through the lens of vector function architecture (VFA), a non-traditional computing paradigm which produces a fixed dimensional …  Read more

User participation has been regarded as an empowerment tool to help low-income people to improve housing at a low cost. It was implemented by the Community Design Workshop during the attempts at housing rehabilitation in Pointe St. Charles in the early 1970's. This thesis is focused on the long-term results of user participation employed by the CDW. Both the current physical conditions of the CDW's projects and the inhabitants' attitudes towards participation, one generation after its implementation, were studied. The research shows that the CDW's efforts involving users in housing rehabilitation not only resulted in improved housing conditions for the …  Read more

Thermal processing is the most widely used method of destroying pathogenic microorganisms of public health concern and reducing the activity of enzymes and microorganisms that are responsible for their spoilage. However, the severity of heat treatment involved during thermal processing also affects the quality and nutritional attributes. This study was conducted to evaluate the degradation kinetics of quality attributes in vegetables, evaluation of their retention during reciprocation agitation thermal processing. First, the kinetics of thermal degradation of texture and color and antioxidant activity in potato and radish at different temperatures were evaluated. Subsequently, the effect of processing factors (temperature and …  Read more

High breakdown point, bounded influence and high efficiency at the Gaussian model are desired properties of robust regression estimators. Robustness of validity, robustness of efficiency and high breakdown point size and power are the fundamental goals in robust testing. The objective of this dissertation is to examine the finite-sample properties of robust estimators and tests, and to find some useful applications for them. This is accomplished by extensive Monte Carlo experiments and other inference techniques in various contamination situations. In the linear regression model with an outlying regressor and deviations from the normal error distribution, robust estimators demonstrate noticeable advantages …  Read more

La façon dont les modificateurs de la chromatine régulent les divers processus biologiques et pathologiques est une question émergente. La protéine BRPF1 est un régulateur épigénétique unique avec deux doigts de zinc de PHD, un bromodomaine et un domaine de PWWP. De plus, elle peut former des complexes multiples avec les histones acétyltransférases MOZ, MORF et HBO1. Afin d'identifier les fonctions biologiques de la protéine BRPF1 in vivo, l'expression spatio-temporelle de la Brpf1 a d'abord été cartographiée en utilisant une souche de souris exprimant un gène rapporteur LacZ. L'analyse a révélé une expression dynamique dans les tissus extra-embryonnaires, embryonnaires et …  Read more

O'Donnell, Kieran (Supervisor2)  Read more

Witcher, Michael (Supervisor1)  Read more

Les maladies d'origine alimentaire causées par Salmonella non typhique et Campylobacter posent des défis importants pour la santé publique et l'économie au Canada. Cette étude visait à estimer les coûts économiques et le fardeau sanitaire de ces infections, en différenciant les souches résistantes aux antimicrobiens (RAM) et les souches sensibles de 2015 à 2019. De plus, l'étude a évalué l'impact des réductions volontaires de l'utilisation des antimicrobiens dans l'industrie avicole sur l'incidence et le fardeau économique de ces infections. En utilisant des modèles de Markov combinés à une analyse input-output, l'étude a quantifié les impacts microéconomiques et macroéconomiques sur la …  Read more

Information on the variability of precipitation process is essential for the planning, design and management of various water resources systems. Furthermore, recent assessment reports on climate change have indicated a worldwide increase in the frequency of extreme storm events for the late 20th century because of global warming. Consequently, research on developing innovative approaches for limiting and adapting climate change impacts on water infrastructures is highly critical due to the substantial investments involved. Global Climate Models (GCMs) have been commonly used in various studies for assessing these potential impacts. However, outputs from these GCMs (generally greater than 200 km) are …  Read more

Les aciers fortement alliés suscitent un intérêt croissant parmi les chercheurs en raison de leurs propriétés mécaniques avancées, de leur résistance à la corrosion, de leurs propriétés électromagnétiques, etc. De plus, l'ajout d'éléments d'alliage légers comme Al et Si dans les aciers fortement alliés peut également réduire le poids de l'acier, ce qui est une application prometteuse dans l'industrie automobile écologique. En revanche, l'introduction du Mn dans les aciers augmente la solubilité du phosphore en raison de sa forte affinité avec le phosphore. Le système d'alliage à six composants Fe-Mn-Al-Si-C-P est très important pour la production des aciers à haute …  Read more

The studies presented in this thesis investigated the mechanism responsible for glucococorticoid secretion during graft-versus-host disease (GVHD), and the role of endogenous glucocorticoids on the outcome of the disease. GVHD was induced in unirradiated F1 hybrid mice by an intravenous injection of parental lymphoid cells. Our results demonstrated that the secretion of glucocorticoids during GVHD was independent of pituitary adrenocorticotropin hormone (ACTH). However, adrenal hyperactivity was associated with increased expression of proopiomelanocortin (POMC) mRNA in the adrenal glands of GVHD mice. Expression of adrenal POMC transcripts was not due to mononuclear infiltrates. The transcripts for interleukin-12, a cytokine produced by …  Read more

The structure of the carbohydrate associated with glycoproteins was examined in various human colonic tumour cells in culture following incubation with labeled sugars. Glycopeptides obtained by pronase digestion of the cell surface glycoproteins of three human colon tumours (HCT-8R, CaCo-2, and HCT-15) were compared with those from cells (CCL 239) derived normal adult colon. The tumour cells contain large molecular weight fucose-labeled glycopeptides that are absent in the CCL 239 cells. The large molecular weight fucose- and glucosamine-labeled glycopeptides from HCT-8R cells contain mainly mild alkali labile O-linked oligosaccharides, whereas those isolated from CaCo-2 cells contain primarily N-linked polylactosaminoglycans which …  Read more

The demands of present day industry for machines of ever increasing complexity and durability has accentuated the need for the improvement in the art of metal casting. This particular method of shaping metals has in fact become so expedient, that a concerted effort is being made to overcome the multitude of practical problems that still exist in the casting industry. Many of the solutions to these problems, particularly those concerning ingot quality, are only empirical and are not based on the knowledge of the fundamental mechanisms of solidification. [...]  Read more

Segregation which occurs in slowly cooled castings and in the direction indicated by the equilibrium diagram is called "normal segregation". The first crystals to separate from the molten alloy during solidification are rich in the higher melting point alloy and occupy a position close to the mold face. As the solidification proceeds the growing dendrites push before them the residual liquid which is becoming continually enriched in the lower melting point alloy (usually the alloy of high solute concentration). [...]  Read more

Classification of the amine oxidase is at best beset with difficulties and it is important to define monoamine oxidase in such a manner that misunderstandings are reduced to a minimum. [...]  Read more

Sourkes, T. (Supervisor)  Read more

Deux principaux sous-types de cancer colorectal avec différents modèles de croissance histologique ont été décrits pour le CCR métastatique avancé. Les lésions désmoplastiques montrent des réponses robustes aux inhibiteurs angiogéniques (IA) et des taux de survie à 5 ans 2 fois plus longs que les patients atteints de lésions de type remplacement. De plus, on pense que la résistance à l'IA est associée à une conversion de desmoplastique en lésions de type remplacement. Nous avons généré des lignées organoïdes dérivées de tumeurs CRC-LM affichant un modèle désmoplasique ou remplacement et nous avons tenté de modéliser les caractéristiques de croissance en …  Read more

Deux variétés de L'écorce de fèves de cacao (CBS, NAC et CCN) s'est avérée être une source importante d'hydrates de carbone, notamment de fibres alimentaires (50,1-61,4%), de protéines (12,7-19,7%) et de polyphénols. L'extraction des polysaccharides de la paroi cellulaire de la CBS a également été étudiée. Les extractions alcalines (0,5 et 4M KOH) ont permis de récupérer un profil riche en polysaccharides de pectine (PS, 80,6-86%). L'augmentation de la concentration alcaline a entraîné un déplacement de la récupération des fractions de poids moléculaire élevé vers les fractions de faible poids moléculaire. Les MW de l'extrait 4M étaient de 6,3 et …  Read more

Les alliages de magnésium (Mg) sont des métaux structuraux critiques pour l'industrie automobile en raison de leur faible densité et de leur rapport poids-force élevé. Les caractéristiques de ces composants automobiles réduisent la consommation de carburant et, par conséquent, l'impact environnemental grâce à une réduction des rejets de gaz à effet de serre. Cependant, la faible résistance à la corrosion de ces alliages limite leur application, en particulier lorsqu'ils sont exposés à des conditions de service rugueuses. Les stratégies actuelles d'atténuation de la corrosion dans les alliages de Mg peuvent être synthétisées en deux méthodes : (i) protection contre la …  Read more

We shall argue that, in order for the law to fulfill its task in the field of social justice, it should take into account the collective structure of society. We will consider, especially through Quebec's class action, how state law grasps the reality of a corporate society entranched with conflicts arising from unequal social relationships. We will demonstrate that, in favoring a vision of society made of individual components, Quebec's class action fails in its attempt to reflect the collective dimension of conflicts. Hence, it does not allow unorganized social groups to influence social relationships in a significant manner. However …  Read more

Polyurethanes (PU) are versatile materials that find applications in many industries. However, there has been an increase in the awareness against the toxicity of isocyanates, which is a base monomer of PUs, on the environment and the public health, and investigations have led to the synthesis of non-isocyanate polyurethanes (NIPU) through different routes. Polyhydroxyurethanes (PHU) constitute one category of NIPUs, and their linear version is prepared from the polyaddition of cyclic dicarbonates and diamines, which are abundant monomers that can be synthesized from bio-based building blocks. Hence, this work investigates the synthesis of bio-sourced PHUs that could potentially replace PUs …  Read more

Vagal and mechanical aspects or ventilatory control have been studied. The behavior or vagal inspiratory inhibitory influence following lung inflations was assessed by determining the excitatory influence required to terminate apnea. It was found that, following inflation, vagal inhibitory influence declines rapidly and then attains a plateau which varies with lung volume. The duration of apnea was found to be critically affected by the course of chemical events following inflation and is therefore, unsuitable for quantitating the vagal inhibitory influence. An alternate method is described based on comparison of the unloaded tidal volume with the inspiratory pressure wave generated following …  Read more

L'usage de paiements à la performance pour compenser les salariés non-cadres aux Etats-Unis a largement augmenté depuis les années 1980. Cette dissertation présente trois études qui examinent les implications empiriques de ces structures compensatoires sur le marché du travail Américain. La première étude enquête si une plus grosse quantité de paiements à la performance dans les mesures de salaire de l'échantillon de Mars du Current Population Survey (CPS) que dans celles de l'échantillon Merged Outgoing Rotation Group (MORG) du CPS contribue au niveau plus élevé et aux tendances divergentes dans l'inégalité salarial résiduelle entre les deux échantillons. Lemieux (2006) et …  Read more

L'Histoire Ecclésiastique d'Eusebius de Casearea est le commencement de l'historiographie chrétienne. Ce premier effort d'une histoire complète de l'église chrétienne a été marqué par l'aura de la persécution en laquelle la théologie chrétienne a été développée, et aussi par la tradition apologétique littéraire. L'historiographie d'Eusebius était intentionnellement apologétique et prescriptible. Cette Histoire recherchée a essaye de convaincre chrono graphiquement et théologiquement le peuple que le message chrétien était supérieur. En outre, l'Histoire Ecclésiastique a commémoré les individus idéalisés et prescrit les comportements appropriés pour les lecteurs du quatrième siècle. Un texte martyrological préservé par Eusebius—les Martyres de Lyons—est un exemplaire. …  Read more

Space stations represent a watershed in man's exploitation and utilization of the space milieu. The several factors of: array of hardware; proliferation of space capability; constant presence of man in orbit; variety of activities; and multiplicity of participants, all coalesce to create an unprecedented era in man's conquest of space. In addition to these scientific and technological developments, this thesis addresses the policy implications for all the current participants in the Space Stations' Era. This is then applied to the US/International Space Station project to assess the legal implications which this precedental co-operative venture provokes. Thus, the status of the …  Read more