McGill University Thèses et mémoires par auteur commençant par R

Souza, Raphael de (Supervisor)  Lire la suite

High circulating neutrophil to lymphocyte ratio (NLR) has been shown to be associated with poor oncologic outcomes. This raises the question as to if neutrophils play a causative role in driving tumor progression. Accordingly, the first aim of this project was to determine if high NLR in cancer patients is associated with tumor-promoting neutrophils. In this aim, we also studied the involvement of netosis in lymph node metastasis. It has been shown that tumor-associated neutrophils (TANs) exhibit phenotypic diversity and plasticity. However, most of these studies were in animals using aggressive cancer cell lines. Therefore, in the second aim, we …  Lire la suite

Computer programs were developed to perform creep tests on three microalloyed steels, with the aim of determining the precipitation kinetics of VN in austenite in one of the steels. This was a commercial 0.01% Ti- 0.12% V- 0.25% Mo steel. The other two were niobium steels with low (0.04% Nb) and high (0.07% Nb) niobium levels, respectively. The Ti-V-Mo steel was tested at various stresses between 30 and 50 MPa in the temperature range 850-900$ sp circ$C. A mathematical equation was fitted to the creep strain vs. time curves and the creep strain was expressed as a function of time. …  Lire la suite

Une matrice de préférences M contient une entrée pour chaque paire de candidats dans une élection, dont la valeur p_{ij} représente la proportion d’électeurs qui préfèrent le candidat i au candidat j. La matrice est rationalisable si elle est cohérente avec un ensemble d’électeurs dont les préférences forment des ordres totaux. Un problème ouvert bien connu cherche une caractérisation concise des matrices de préférences rationalisables. Dans cet article, nous généralisons cette question de rationalisabilité des matrices et étudions quand une matrice de préférences est cohérente avec un ensemble d’électeurs dont les préférences sont des ordres partiels de largeur ������. La …  Lire la suite

This thesis concerns the possible existence of central nervous system (CNS) chemosensitive mechanisms influencing sympathetic activity. The thesis is based on observations of sympathetic neuron and cardiovascular responses to CNS ischemia, systemic hypoxia and systemic hypercapnia. Investigation of the pressor response to cerebral ischemia in the cat indicates that it is mediated by superficial regions of the ventral medulla also involved in the pressor response to central hypercapnia. Experiments concerning the sympathetic response to systemic hypoxia in the CNS-intact sino-aortic denervated cat revealed a two-component response of the firing rates of single sympathetic preganglionic neurons (SPN), the mass activity of …  Lire la suite

A difficult research problem in the teleoperation of robot hands by hands masters is the development of an accurate method to transform the measured human hand poses to the robot hand. This thesis describes a novel optimized fingertip mapping (OFM) algorithm developed to perform the pose transformations and an accurate modeling method for the human hand. The OFM algorithm has been implemented to teleoperate the Utah/MIT Dextrous Hand (UMDH) by a new hand master: the Utah Dextrous Hand Master (UDHM). The keystone of the algorithm is the mapping of both the human fingertip positions and orientations to the robot finger. …  Lire la suite

La présente thèse examine l’évolution et la fonction du « cadre narratif » (setting) dans la fiction allemande moderne à travers une analyse littéraire computationnelle. Plus particulièrement, elle étudie la façon avec laquelle les différents espaces fictifs sont construits et perçus. La narratologie, la phénoménologie et la cognition incarnée servent de base théorique à notre analyse. De plus, l’étude explore l’interaction réciproque entre les personnages et le cadre narratif à partir du modèle triadique de Gerhard Hoffman – gestimmter Raum (espace reflétant l’humeur et l’atmosphère), Aktionsraum (espace d’action), Anschauungsraum (champ de vision) – et d’une catégorie additionnelle (espace descriptif). Le …  Lire la suite

Of A Covered Harvest is a twenty minute music composition for alto solo, mixed double choir (SSAATTBB) and percussion. It uses the following texts: Sacrifice by Alicia Munoz; Non Linear by Phyllis Webb and ancient Mayan words. The piece explores the themes of power, choice and the crowd versus the individual using the musical depiction of a ritual human sacrifice as a forum for commentary. The three part structure of the piece is delineated by the narration of the ritual by the choir: preparation, sacrifice and resolution, and by the emotional reaction to the sacrifice by the alto solo (victim): …  Lire la suite

Phosphatases of regenerating liver (PRL1, PRL2, and PRL3) are a family of dual-specificity phosphatases that regulate cell growth, differentiation, and proliferation. The PRLs are highly expressed in most cancers, and high expression of PRLs often correlates with poor patient prognosis. To elucidate the oncogenic role of PRLs, mouse embryonic stem cells with a deletion of PRL-2 were used to generate three-dimensional organoids. It was found that organoids with a PRL2 deletion had a significant disadvantage in growth, suggesting the importance of PRLs in neoplasia. Additionally, we found evidence suggesting that PRL1 and PRL2 have compensatory functions. Furthermore, the interaction between …  Lire la suite

Breuleux, Alain (Supervisor)  Lire la suite

Les maladies dégénératives de la rétine constituent une cause majeure de perte de vision et résultent de la dégénérescence des bâtonnets et des cônes. Cependant, après la perte des photorécepteurs, d’autres neurones rétiniens demeurent intacts et peuvent être ciblés par des stratégies optogénétiques visant à restaurer la sensibilité à la lumière dans une rétine aveugle. La rétine saine transmet l’information visuelle à travers de multiples canaux parallèles via différents types fonctionnels de cellules ganglionnaires rétiniennes (RGCs), chacun codant des caractéristiques visuelles spécifiques telles que le mouvement, le contraste, l’orientation, la direction, la taille, etc. Les stratégies actuelles de restauration optogénétique …  Lire la suite

Le contrôle des coups de terrain dans les mines souterraines est un problème difficile, en particulier dans les mines de métaux profondes où le taux d'extraction du minerai est élevé. L'augmentation de la probabilité des coups de terrain de roches peut être une source d'inquiétude pour la sécurité des exploitants miniers. Les paramètres associés aux coups de terrain sont généralement liés aux caractéristiques géologiques telles que les dykes et les failles, aux propriétés mécaniques des roches, aux activités sismiques et aux taux de production. Les aspects de l'exploitation minière tels que la séquence des chantiers, la direction de l'exploitation, la …  Lire la suite

Introduction et objectif : Les agents de santé communautaires (ASC) sont des acteurs clés qui fournissent des services de santé aux populations sous-desservies et sont souvent le seul point d'entrée des soins de santé pour les communautés marginalisées. La formation des ASC et d'autres formes d'interventions de formation en santé communautaire échouent parfois à long terme car les facteurs culturels locaux ne sont pas pris en compte. Le projet de Formation et d’Éducation pour la Santé en Communauté Andine (TEACH) de l’Université McGill a été envisagé pour la formation des ASC dans les communautés autochtones rurales du nord de l’Équateur. …  Lire la suite

Successful navigation requires the generation of signals that remain consistent, regardless of environmental changes. This consistency can be achieved by constraining neuronal activity to low-dimensional subspaces that align with spatial aspects of an animal's behavior. Notably, during sleep—a period of diminished external input—pairwise coordination persists within different regions of the spatial navigation system. This is particularly evident in grid cells in the medial entorhinal cortex (MEC) and head-direction (HD) cells in the anterodorsal nucleus (ADn) of the thalamus, supporting the notion that network activity remains organized under all conditions. Given the essential role of the ADn in grid cell formation, …  Lire la suite

Alterations in thyroid function affect carbohydrate metabolism in man. Hyperthyroidism frequently increases insulin requirements in diabetic subjects (52) whereas, hypothyroidism decreases the severity of the disease and thus, the amount of insulin required (48). In the partially pancreatectomized rat, Houssay found thyroid hormone to be diabetogenic and thyroidectomy to inhibit the development of diabetes in the same experimental model.  Lire la suite

This is a study of the use of language in Joseph Heller's novels Catch-22, Something Happened, Good as Gold, God Knows and Picture This. Heller's fiction is characterized by self-negating sentences and logic, a repetitive story line and circular structure. Each novel concerns the relationship between people and language, but the relationship invariably is circular and inherently non-progressive. The separation between people and language, analogous to the separation between existence and expression, is the basis for Heller's thematics. Joseph Heller is a novelist who writes about language. Heller's novels all contain or evoke a common system characterized by self-containment and …  Lire la suite

Modifications of Helly's and of Stieve's fixatives, and of Bowie stain demonstrate with excellent results the components of the JG complex. A marked activating effect results by the combined addition of BaCI and CoCl2 for the histochemical demonstration of the hexosemonophosphate2 shunt enzymes. A semi-quantitative index was derived for assessing the activity of these enzymes in the macula densa (MDL), with parallel measurements of the juxta-glomerular cell granularity (JGI) and renin. Complete aortic ligature between the two renal arteries in rats over 300 g consistently produced atrophic left kidneys accompanied by hypertension. JGI and MDI studies on sex and various …  Lire la suite

The use of Radial Basis Function (RBF) is an attractive approach for mesh deformation of viscous three-dimensional multi-block structured meshes on complex aircraft configurations due to its simplicity in implementation, parallelizability for multi-processor simulations and the availability of the mesh sensitivities for design optimization. A novel curvature-based algorithm is developed to reduce the number of RBF points employed to represent the design surface and reduce the condition number of the RBF matrix. In addition, a novel technique to pre-process multiblock structured grids for RBF mesh deformation is proposed. The approach reduces the preprocessing time as well as ensures that RBF …  Lire la suite

This thesis is a study of Wilfred Cantwell Smith's contribution to the field of religious studies, with special reference to his study of Islam. Smith's views as a historian of religion, as an Islamicist and as the pioneer of a new approach to the study of other men's faith are of great significance. This thesis studies his work on Islam in the light of the development of his ideas with regard to the concept of religion and the approaches to studying it. The evolution of Smith's understanding of Islam is classified here into three phases. During the first phase, Smith's …  Lire la suite

Patients diagnosed with disorders of consciousness are difficult to assess as their behavioural responsiveness may be attenuated by a variety of factors and may not be reflective of their actual level of consciousness. This thesis focuses on electroencephalography (EEG) methods for detecting and assessing consciousness directly from an individual's brain activity in populations with uncertain levels of awareness. By addressing some of the current controversy in the field, investigating new approaches to consciousness assessment, and by combining both event-related and continuous EEG analyses, this thesis establishes and presents a more robust and holistic approach to assessing disorders of consciousness. Critical …  Lire la suite

The kinetics of spinodal decomposition has been studied by Monte Carlo renormalization group method. Using a standard block-spin transformation, we numerically renormalize the evolving configurations during the phase separation of a kinetic Ising model with spin-exchange dynamics. We find that in the scaling regime, the average domain size $R$($t$) grows in time as $R$ $ sim$ $t sp{n}$, with $n$ = 0.338 $ pm$ 0.008 consistent with the classical $n$ = 1/3 result of Lifshitz and Slyozov. A scaling form for the structure factor is obtained, which is invariant under the renormalization group transformation. The fluctuations around the average domain …  Lire la suite

Carotenoids are yellow-red plant pigments with antioxidant potential that humans primarily obtain from their diet. Carotenoid intake and status are consistently associated with a reduced risk of skin, age-related, and non-communicable diseases, but intervention studies have demonstrated a broad range of responses. Among various host-related factors that may account for this interindividual variation, the gut microbiome has sparsely been explored. Probiotics have also been proposed to enhance phytochemical status, but no human intervention studies have been conducted. In the present work, a 10-week, double-blind, randomized controlled trial involving 37 premenopausal women (average age of 40) was conducted. All participants took …  Lire la suite

Contexte: Les caroténoïdes sont des pigments végétaux jaune-rouge obtenus à partir de fruits et de légumes (FL), qui se déposent en grande partie dans la peau et servent de biomarqueur à l'apport en FL. Les méthodes actuelles d'évaluation des caroténoïdes (évaluation du régime alimentaire, analyse sanguine par CLHP, spectrophotométrie cutanée) peuvent être biaisées, longues, complexes et coûteuses. Objectif: Nous avions pour objectif d'évaluer la faisabilité de l'analyse numérique de la couleur de la peau contre l'analyse spectrophotométrique pour l'estimation du contenu en caroténoïdes de la peau et d'étudier l'impact de la coloration de la peau du visage induite par les …  Lire la suite

Un modèle semi-analytique a été développé pour résoudre la réflexion de Mach dans les jets axisymmetrique en sur-détente, juste en aval de la sortie d'une tuyère. Le flux considéré est constant, sans viscosité, composé d'un gaz idéal. Le modèle se compose de deux champs d'écoulement, l'un incident et l'autre réfléchi, résolus à l'aide de la méthode des caractéristiques, et d'un troisième champ d'écoulement d'onde de Mach résolu par des relations quasi unidimensionnelles. Dans certains cas, le modèle est capable de produire des champs d'écoulement supplémentaires. Ceux-ci sont calculés soit pour affiner les calculs autour de l'axe de symétrie pour de …  Lire la suite

Leclerc, Catherine (Supervisor1)  Lire la suite

Dans de nombreux pays en voie de développement, les accouchements à domicile sont fréquents et entrainent souvent des complications imprévisibles, blessures ou autres évènements indésirables qui contribuent à la morbidité et mortalité à la fois maternelle et infantile. L'objectif de cette étude était d'identifier d'importants déterminants associés avec les accouchements à domicile afin d'éclairer les politiques de santé dans l'Amazonie péruvienne.Une étude de cas-témoins appariés a été réalisée (cas = accouchement à domicile et contrôle = accouchement à l'hopital). Les données ont été collectées par des questionnaires pré-testés administrés par un intervieweur auprès de 112 femmes qui ont accouché dans …  Lire la suite

The latitudinal extent of the tropics is of great consequence because it affects agricultural production, water supply, storm frequency, and other factors of socioeconomic importance. The tropics can be defined by climatological metrics such as Hadley cell width, and observations show that the tropics have been expanding poleward since 1979.Tropical width is influenced by both anthropogenic forcing and patterns of large-scale internal climate variability, and the tropics have been expanding faster than coupled models forced with historic levels of anthropogenic forcing. The relative importance of each expansion mechanism has remained unclear since it is difficult to separate the signals of …  Lire la suite

The writer discusses the relation between the motor vehicle and total highway costs and presents a method of distributing this cost among motor vehicles in such a manner that each vehicle contributes directly in proportion to the amount of use which it makes of the highways. The underlying principle of the method is in the measurement of highway wear andtear in terms of impact force on the highway. From impact force, slightly modified by highway space occupied and a limited application of the 'ability to pay' canon of taxation, a schedule of relative ratios showing the proportional place that different …  Lire la suite

The writer points out the profound influence which the railways, as "equalisers of opportunity," have had in creating and maintaining the existing economic structure of Canada and how the recent development of competition from motor transport and in lesser degree, air transport, threatens to make it impossible for them to continue this function, with serious consequences to the economic life of the nation. After a discussion of the vexed question of motor vehicle taxation and of the various means which might be taken to meet the growing competition from motor transport, it is concluded that the rationalisation of railway services …  Lire la suite

Liu, Xue (Supervisor2)  Lire la suite

Gvili, Gal (Supervisor2)  Lire la suite

A design analysis of a telecentric microchannel relay system developed for use with a smart pixel based photonic backplane is presented. The interconnect uses a clustered window geometry in which optoelectronic device windows are grouped together about the axis of each microchannel. A Gaussian beam propagation analysis is used to analyze the trade-off between window size, window density, transistor count per smart pixel, and lenslet f-number for three cases of window clustering. The results of this analysis shows that by using this approach, a window density of 4,000 windows/cm$ sp2$ is obtained for a window size of 30 microns and …  Lire la suite

The design and testing of very-large-scale-integrated optoelectronic (VLSI-OE) microchips will be described in the context of a free-space optical backplane system. The optical backplane has the potential for providing an enormous amount of bandwidth for telecommunication switching systems and massively parallel computing machines. A free-space optical backplane uses optical design techniques to relay beams of light from the surface of one microchip to the surface of another. By using light to interconnect microchips, the problems associated with high-speed electronic interconnects are avoided. By exploiting the 2-dimensional surface area of the microchips, large numbers of parallel optical interconnections are possible using …  Lire la suite

Background. Up to 1600 Canadians/yr suffer a serious complication due to the diagnostic test ERCP (endoscopic retrograde cholangiopancreatography) used in the management of patients with suspected biliary obstruction. MRCP (magnetic resonance cholangiopancreatography) is a new highly accurate noninvasive alternative that is not associated with any significant complications. Aims. To assess the real-life effectiveness and costs of MRCP versus ERCP in a planned interim analysis of a randomized clinical trial, in intermediate risk patients. To assist in the decision regarding study continuation versus termination. Methods. 200 patients with a clinical and/or ultrasonographic (US) suspicion of obstruction were randomized to MRCP or …  Lire la suite

The area studied is situated in the southwestern part of Quebec Province near the Ontario border south of the Canadian Shield and along the Lake of Two Mountains. The area is approximately 463 square miles in size. [...]  Lire la suite

Hall, Oswald (Supervisor)  Lire la suite

The latch-state is the capacity of smooth muscle to maintain force for long periods of time with low energy consumption. The prevalent theory to explain the latch-state suggests that if myosin gets deactivated (dephosphorylated) while attached to actin, it remains attached and maintains force. Other theories suggest that dephosphorylated and detached myosin can bind to actin to maintain force and that actin regulatory proteins participate in the force maintenance. All theories of the latch-state were based on measurements performed at the whole muscle level and were never confirmed at the molecular level. Verifying the latch-state theories at the molecular level …  Lire la suite

The N3 position of thymidine was alkylated with different sized bromoalkyl phthalimide linkers in generally good yields, with no alkylation observed on the sugar ring. The free amino group, available after methylamine deprotection of the phthalimide linker, was protected with the levulinyl protecting group (e.g., 20). Branched 'Y'-shaped nucleic acids containing branching monomer 20 were synthesized using standard solid phase synthetic methodology and complexes of these branched nucleic acids with one and two mole-equivalents of linear complement dA$ sb{10}$ are investigated by thermal melting. At the branching point the levulinic amide exhibited poor lability to Letsinger's hydrazine solution and proved …  Lire la suite

Multiple Myeloma (MM) cell survival has been shown to depend on precise control of protein production and degradation. Disruption of protein catabolism through proteosomal or aggresomal blockade results in MM cell death. We hypothesized that inhibiting protein production would have a similarly toxic effect in MM. We explored the consequences of inhibiting mRNA translation in MM using silvestrol, a powerful inhibitor of ribosomal recruitment, which preferentially disrupts the production of certain cell regulatory and survival proteins. A panel of silvestrol-treated MM cell lines showed profound inhibition of growth and a rapid induction of apoptosis, as seen by MTT viability and …  Lire la suite

Comme d'autres segments du marché, les technologies de transport continuent à émerger, avancer et prospérer offrant aux chercheurs et aux praticiens la possibilité de contester les principes établis et de découvrir de nouveaux horizons. Cette thèse vise à étudier l'utilisation des données Bluetooth et GPS téléphones intelligents (Smartphone) pour calculer les temps de déplacement (ou de retards) et analyser l'influence de certains facteurs tels que la météo et l'environnement bâti. Ce travail démontre l'applicabilité pratique des nouvelles sources de données contre les technologies et méthodes plus traditionnelles. Premièrement, les données Bluetooth recueillies le long d'une artère majeure au cours de …  Lire la suite

In the context of the contemporary rebirth of interest in contemplative prayer in the Christian tradition, many people, e.g., Laurence Freeman (1995), Eileen O'Hea (1990), Bede Griffiths (1991), have begun to examine the writings of John Main. This thesis presents John Main's understanding of Christian Meditation, in particular, his recovery from the Desert monks of the 4th century, of the practice of 'pure prayer' (silent meditation using a prayer word or mantra). Main recovered the use of a mantra as a way of meditation within the tradition of the Christian church. The thesis also discusses some aspects of the Christian …  Lire la suite

En réponse à un droit international privé (DIPr) rigide et prétendument neutre, le principe de proximité a acquis une pertinence indéniable dans les litiges transfrontaliers. Ainsi, face à une affaire internationale, plutôt que d'appliquer mécaniquement une règle traditionnelle du DIPr, ce principe a souvent été utilisé pour identifier quelle loi est, en fait, la plus liée au litige en cause. Au-delà du domaine du choix de la loi, la proximité a également pris de l’importance sur les conflits de juridiction, avec une logique similaire, selon laquelle une juridiction donnée est réputée raisonnable si elle respecte les paramètres de proximité, une …  Lire la suite

The warm rolling of steels is becoming an increasingly common practice in industry. Nevertheless, the poor formability of warm rolled low carbon (LC) steels is problematic, as this property is important in deep drawing applications, which require uniform deformation. Compression tests were conducted to study the effect of chromium content on rate sensitivity (m), using two experimental LC-chromium alloys and an extralow carbon (ELC) steel. Samples were tested at various temperatures and strain rates, and the flow stress was measured for each condition. A second dynamic strain aging (DSA) peak was present in both LC-Cr alloyed steels, indicating that chromium …  Lire la suite

This guide provides lessons which enable teachers with little or no experience with tape recorders and other audio equipment to integrate radio production and analysis into the language art curriculum. Chapter two provides a summary of the media education and language theory that inform the activities presented in this guide. Chapter five provides perspectives on and strategies for evaluating student work with radio. The appendices include reproducible masters, information about sound technology, classroom organization and methods of reaching audiences, and a list of resources  Lire la suite