McGill University Thèses et mémoires par auteur commençant par T

Acute megakaryoblastic leukemia (AMKL) is a rare and fatal subtype of acute myeloid leukemia (AML), affecting children with or without Down Syndrome (DS-AMKL, non-DS-AMKL respectively). Both DS-AMKL and non-DS-AMKL are characterized by malignant megakaryoblasts but harbour distinct genetic profiles and prognoses. While non-DS-AMKL is associated with recurrent chimeric oncogenes, DS-AMKL develops in a stepwise sequence: 1) constitutive trisomy 21; 2) acquisition of a GATA1 somatic mutation; and 3) co-acquisition in a secondary genetic alteration (e.g., TP53, EZH2 mutations). Furthermore, compared to non-DS-AMKL, DS-AMKL carries favourable prognoses; however, refractory/relapsed cases are met with dismal cure rates that are in part driven …  Read more

This thesis consists of two essays on the effects of barriers to international investment on risk premium and investors' portfolio holdings. In the first essay, we develop an international asset pricing model in a two-country framework where there are no restrictions in the domestic market (for example the U.S.). On the other hand, trading in the foreign market (for example an Emerging Market) encounters barriers to portfolio flows and short-sale constraints. The model suggests that freely traded assets (for example those traded in the U.S.) are priced with only a global risk premium, whereas assets that trade under capital flow …  Read more

Background and hypothesis: Atherosclerosis is a disease involving the gradual buildup of lipids, fibrotic material, and inflammatory cells in lesions lining the arterial wall, which continually grow and can eventually block local circulation or rupture and form blood clots that cut off circulation elsewhere, culminating in life-threatening diseases such as heart attacks and stroke. Lifestyle modifications and statin drugs help to lower circulating lipids and mitigate these outcomes, but they may still occur nevertheless. Adopting a more mechanistically focused approach, our goal is to restore motility to the lipid-overloaded foam cells that become trapped inside atherosclerotic plaques and contribute to …  Read more

La géranylgéranyl-pyrophosphate synthase humaine (hGGPPS) est une enzyme de la voie du mévalonate qui catalise la formation de géranylgéranyl-pyrophosphate (GGPP) via la condensation du farnésyl-pyrophosphate (FPP) avec l’isopentényl-pyrophosphate (IPP). La GGPP est un substrat clé pour la prénylation de plusieurs protéines de régulation liant la GTP (protéines G), incluant les sous-familles Rho et Rac qui assurent la signalisation cellulaire. Des études biochimiques ont indiqué une relation entre un niveau élevé de GGPP dans les tissus cérébrales et la maladie d’Alzheimer (MA) engendrant un intérêt pour cibler la hGGPPS dans le traitement de la MA. Actuellement, la découverte de médicaments basée …  Read more

Conceptions of community violence that circulate in American society are shaped by, and shape, the way that public health violence intervention programs are designed and implemented. As a conceptual point of departure for public health programming, community violence focuses on acutely violent events, where homicide and/or hospitalization are the potential outcomes. The violence experienced by poor people living in marginal neighborhoods is chronic and does not resemble this conception of violence on which public health intervention programs are based. The violence that is most pressing to these intended service recipients is driven by their immersion in poverty. As a result …  Read more

Designing systems with the ability to make optimal decisions under uncertainty is one of the goals of artificial intelligence. However, in many applications the design of optimal planners is complicated due to imprecise inputs and uncertain outputs resulting from stochastic dynamics. Partially Observable Markov Decision Processes (POMDPs) provide a rich mathematical framework to model these kinds of problems. However, the high computational demand of solution methods for POMDPs is a drawback for applying them in practice. In this thesis, we present a two-fold approach for improving the tractability of POMDP planning. First, we focus on designing good heuristics for POMDP …  Read more

This study examined the prevalence of information epidemics in the physics literature. The primary interest was to find out whether outliers observed on time series charts of literatures are due to information epidemics, whether these epidemics are widespread occurrences in physics, whether literatures showing such rapid growth arise mainly due to the influence of an important work and, if so, what characterizes these literatures. Information epidemics were defined as spurts of growth in the literature of a field that reflect a sudden excitement and increase in activity. It was hypothesized that information epidemics are common occurrences in the growth of …  Read more

Low, Nancy (Internal/Cosupervisor2)  Read more

This thesis addresses calculation of Nash equilibria in a bimatrix game as well as convergence in algorithmic learning for two categories of discrete and discontinuous games, namely bimatrix games and double auction markets.First, a method which does not use estimation is proposed for calculating a Nash equilibrium of the bimatrix game when the fictitious play converges to a Shapley polygon. By using a lexicographical order, the existence of a Nash equilibrium for every Shapley polygon in a bimatrix game is proven. The calculation of the Nash equilibrium follows from a simple matrix reduction technique which imposes no assumption about the …  Read more

Electrochemically-induced changes in surface stress at the solid-liquid interface are measured using a differential cantilever-based sensor. The simultaneous, in situ measurements of the current (charge) and interfacial stress changes are performed by employing an AFM cantilever as both the working electrode (in a conventional three-probe electrochemical cell configuration) and as the mechanical transducer (bending of the cantilever). The custom-built instrument achieves a surface stress sensitivity of 1x10-4 N/m and a dynamic range of 5x105. Combining electrochemistry with cantilever-based sensing provides the extra surface characterization capability essential for the interpretation of the origin of the surface stress. The objective of the …  Read more

The question of consumption and clothing in Tehran has long captivated not only scholars of Iran but also everyday Iranians residing both inside and outside of the country. Theories about why the Islamic Republic's capital is gripped with a passion for clothing have enthralled everyday Tehranis who themselves participate in this consumerism. This thesis begins by unsettling popular claims that Iranians, particularly women, who participate in this consumption are doing so to push against the Islamic Republic's regime and out of a desire to be "western." Instead, this thesis looks at how specifically middle-class women use everyday dressing to navigate …  Read more

Meiosis is a specialized cell division program during which a reduction in the genetic content from diploid progenitor cells leads to the formation of haploid gametes, which contain only one copy of each chromosome. This process is crucial for sexual reproduction, where the fusion of two complementing haploid gametes restores diploidy in the resulting zygote. Critical to the production of euploid gametes is the segregation of homologous chromosomes to opposing poles of the cell during meiosis I. This process is carefully choreographed, and requires coordination of three key steps: pairing, synapsis and recombination. Using immunohistochemical analysis, the landmark prophase I …  Read more

This study is concerned with the 2-D transient energy storage and energy recovery for arbitrary-shaped double pipe latent heat thermal energy storage (LHTES) units for the efficient utilization of the solar energy and industrial waste heat. The phase change material (PCM) which is selected here is commercially available paraffin wax which melts and freezes over a fixed temperature range of 8.7oC. The arbitrary nature of the computational domain is accounted for through the use of a non-orthogonal boundary-fitted coordinate (BFC) system on a staggered grid arrangement. An enthalpy-porosity scheme is used to model the various complex mushy region phase change …  Read more

Solar energy is an intermittent supply source of energy. To efficiently utilize this free renewable energy source some form of thermal energy storage devices are necessary. Phase change materials (PCMs), because of their high energy density storage capacity and near isothermal phase change characteristics, have proven to be promising candidates for latent heat thermal energy storage (LHTES) devices. Among the various LHTES devices for low temperature residential heating and cooling applications, the shell-and-tube type heat exchanging devices are the most simple to operate and can be easily fabricated. This work numerically investigates the buoyancy driven heat transfer process during melting …  Read more

Introduction : La dégénérescence des disques intervertébraux (DIVs) est une des sources connues de lombalgie. Cette condition, reconnue sous le nom de discopathie dégénérative, peut être conséquente du vieillissement, d'un traumatisme ou de prédispositions génétiques. Un meilleur aperçu du profil histologique de DIVs sains et dégénérés contribuera à approfondir notre compréhension des effets du processus dégénératif sur la douleur chronique. De plus, l'avancée des connaissances contribuera au développement de meilleurs diagnostics ainsi qu'à de meilleures stratégies thérapeutiques lors de la prise en charge de patients souffrant de lombalgie. La méthode standard de coloration tissulaire à base d'hématoxyline-éosine (H&E), utilisée seule …  Read more

La science de l'information est un domaine interdisciplinaire qui interagit avec d'autres à travers ses frontières intellectuelles. Bien qu'il y ait beaucoup de recherches sur la nature interdisciplinaire des sciences de l'information, peu de recherches identifient la nature, l'étendue et la qualité de ces interactions extradisciplinaires. Le but de l'étude est de fournir une analyse approfondie des contextes implicites et explicites de citations pour explorer la nature de citations que la littérature des sciences de l'information reçoit d'autres disciplines. Cette analyse approfondie révèle le niveau de l'impact des citations auquel la littérature des sciences de l'information contribue pour l'avancement des …  Read more

Low vitamin D status, defined by circulating 25-hydroxy vitamin D (25(OH)D) <50 or <75 nmol/L is prevalent among pregnant women and has been associated with neonatal rickets and gestational diabetes mellitus (GDM). Osteocalcin (OC), a bone formation biomarker, linking the bone to glucose metabolism is stimulated by 1,25-dihydroxyvitamin D (1,25(OH)2D), the active form of vitamin D. In the first study, maternal serum 25(OH)D and OC were explored at early and mid-gestation in GDM (case, n=48) vs healthy (control, n=48) Caucasian pregnant women. Maternal serum 25(OH)D was not different (p=0.80) while OC was higher (p=0.006) in those with GDM vs controls …  Read more

A theoretical analysis is presented to determine the forces of interaction between an electrically charged cylindrical or spherical particle and a charged plane boundary wall when the particle translates parallel to the wall and rotates around its axis in a symmetric electrolyte at rest. The electroviscous effects, arising from the coupling between the electrical and hydrodynamic equations, are determined as a solution of three partial differential equations, derived from Cox's general theory, for electroviscous ion concentration, electroviscous potential and electroviscous flow field. It is a priori assumed that the double layer thickness surrounding each charged surfaces is much smaller than …  Read more

This research develops an analytical method for predicting the hydrodynamic force experienced by a long slender solid body of arbitrary cross-sectional shape and body centreline configuration, subjected to an unbounded uniform fluid flow. It is assumed the slenderness parameter, K (the ratio of the body cross-sectional length scale the body length) is small ($ ll 1$), the body centreline radius of curvature is everywhere large (of order body length), the cross-sectional shape varies slowly alone the body length, and the Reynolds number $R sb{e}$, based on the body length is of order unity. The inner flow solution for an arbitrary …  Read more

Graph clustering is a very common problem that arise in various fields; e.g., social science, computer networks, bioinformatics, marketing, ecological networks, and political science.In this thesis, several classes of graph clustering algorithms and ideas are reviewed. Furthermore a novel graph clustering algorithm is presented. The algorithm strives to optimize the normalized cut metric, which has proven to be a meaningful assessment of the quality of a clustering, since it takes into account both the similarity of nodes within the same cluster and the dissimilarities of nodes within different clusters. The clustering algorithm we present, which we call "Greedy Agglomerative Normalized …  Read more

Searching for information pervades a wide spectrum of human activity, including learning and problem solving. With recent changes in the amount of information available and the variety of means of retrieval, there is even more need to understand why some searchers are more successful than others. This study was undertaken to advance our understanding of expertise in seeking information on the Web by identifying strategies and attributes that will increase the chance of a successful search on the Web. A model that illustrated the relationship between strategies and attributes and a successful search was also created. The strategies were: Evaluation, …  Read more

Experimental evidence shows that initially homogeneous bidisperse suspensions become unstable due to initial perturbations in particle concentrations. As a result of this instability, the particles segregate and form vertical streams (so-called fingering phenomena) during their sedimentation process. In this thesis we deal with modelling the macroscopic behaviour and studying the stability of the suspension. A continuum model is developed and used in order to model the formation of vertical streams and study the instability of dilute bidisperse suspensions. The macroscopic behaviour of the suspension is closely related to and depends on the microstructure and the relative motion of particles in …  Read more

Yong, Raymond N. (Supervisor)  Read more

This thesis examines the constitutional guarantee of freedom of expression as applied to electronic mass media. It compares the different approaches adopted in Germany, the United States and Canada. After an overview of freedom of expression doctrine in general and the main features of the regulation of electronic mass media the rationalization of this regulation in freedom of expression doctrine is analyzed. The focus of this analysis is how electronic mass media have changed the traditional understanding of fundamental rights and freedoms as purely negative individual guarantees. This change occasions and necessitates a closer look at governmental regulation and the …  Read more

A linear programming (LP) model is formulated to reflect economic, climatic conditions, and cultural practices followed in the pot flower industry of Quebec. The objective is to determine the optimal crop mix that maximizes net returns and optimizes space usage given production and marketing constraints. Decision variables are composed of nine major pot flower varieties with several pot sizes produced for different marketing periods during the year. Data are collected from producers in the Montreal area in 1990, and is supplemented by interviews with ornamental counsellors and citations of governmental publications. Results have shown that the use of LP as …  Read more

Pascal, Gabrielle (Supervisor)  Read more

Changes in the Cree way of life over the last century are reflected by an increased prevalence of type 2 diabetes (T2D). Since traditional medicine (TM) is considered an appropriate complementary approach for T2D treatment and management, suitable delivery methods need to be determined. Using community-approved interview and focus group guides, this qualitative study aimed to understand how the community's cultural practices affect TM use and how TM is perceived by various groups. Two themes emerged from interviews. First, modernization has influenced culture and affects the receptivity of reintroducing TM to the community. Second, participants identified that the health benefits …  Read more

Human telomerase is a ribonucleoprotein complex, minimally composed of a catalytic subunit, hTERT and an RNA component, hTR that contains the template used to synthesize telomere DNA. Telomerase is present in over 80% of all cancer cells. Therefore, an understanding of telomerase regulation is important for cancer research. This thesis work was focused upon the study of telomerase regulation by telomerase associated proteins and alternatively spliced hTERT mRNA variants. Tandem affinity purification (TAP) and immunopurifications with anti-hTERT antibody were used to visualize potential telomerase associated proteins. No specific proteins were identified in TAP-hTERT transfected cells. hTERT was purified from 293 …  Read more

Russell Davidson (Supervisor1)  Read more

We investigate and compare two field theoretical formalisms, namely, the former state-of-the-art but noncovariant Ruckl formula-based formalism developed by K. Haglin and C. Gale, and a more recent covariant formalism developed by P. Lichard, for lepton pair production via soft virtual bremsstrahlung in hadronic reactions. A quantitative study of the discrepancy between both formalisms with regard to rates and total yields of $e sp{+}e sp{-}$ and $ mu sp{+} mu sp{-}$ pair production from radiative pion and quark (antiquark) scattering in ultrarelativistic heavy-ion collisions is made. Dilepton production rates are calculated using the independent particle approximation from kinetic theory, and …  Read more

Les normes CSA A23.3-14 et ACI 318-14 exigent que l’armature de dalle pour le moment négatif auxconnexions de rive soit placée dans une bande de largeur, bb, égale à 1.5 fois l’épaisseur de la dalle de chaquecôté du poteau. Pour examiner l’efficacité de l’armature supérieure dans la bande de largeur, bb, quatrespécimens de connexion dalle-poteau de rive à grande échelle dont les dimensions du poteau et la dispositionde l’armature variaient ont été conçus, construits et testés. Les résultats de ce programme expérimental ontrévélé que les barres d’armature dans la bande de largeur, bb, n’étaient pas toutes éfficaces, surtout quand ils’agissait …  Read more

Gunjal, Kisan (Supervisor)  Read more

This research took a feminist ethnographic approach to analyze, disrupt, and reconfigure ideas about the sexualization of girl dancers in Canada. The following two research questions were examined: (1) What are the cultural practices and influences that reveal how sexualization operates in competitive dance? (2) What is considered “good” and “competitive” training? Data collection took place at the Montréal Centre for Dance, where six months of field observations were conducted alongside semi-structured interviews with competitive dancers and competitive dance parents, supplemented by interviews with competitive dance judges and competition directors outside the studio. A reflexive thematic analysis was employed to …  Read more

La progression d'un haplotype exotique du roseau commun (Phragmites australis (Cav.) Trin ex Steud.) en Amérique du nord réduit la diversité végétale des milieux humides en plus de menacer les haplotypes indigènes de Phragmites australis. La prévention étant plus efficace que le contrôle, une approche spatialement explicite visant à prédire les risques d'invasion par l'haplotype exotique et son impact sur un haplotype indigène a été développée. Cette étude conduite dans un marais protégé du Québec (Canada) visait à : 1) comparer et expliquer la distribution spatiale actuelle de ces deux haplotypes sur la base de leur relation à des variables …  Read more

A community based, cross-sectional survey was undertaken of the anthropometric status of Oromo, non-pregnant women of child bearing age in Kersa subdistrict, southwest Ethiopia. The main purposes of this investigation were to determine normative anthropometric standards and to identify their important determinants. A structured questionnaire was administered by interviewers and anthropometric measurements were completed on 473 non-pregnant women randomly selected and stratified by 5 year age categories from 8 peasant associations. Women in this study sample were light with a mean (SD) weight of 46.9 (5.3) kg. Approximately three quarters weighed less than 50 kg and 34 (7%) less than …  Read more

The effects of buffer additives in capillary electrophoresis (CE) separations of various biologically important molecules were studied. Buffers containing $ beta$-cyclodextrin ($ beta$-CD) and borate were used to separate mixtures of monophosphorylated nucleotide isomers. The electrophoretic mobility of nucleotide isomers was altered as a result of selective complex-forming reactions with $ beta$-CD. In addition, complexation of 5$ sp prime$-nucleotides with borate increased the migration time window and led to better separation. Mono- and di-phosphorylated isomers of the insulin receptor peptide (IRP), were resolved in buffers containing sodium dodecyl sulfate, (SDS). The effects of SDS concentration and pH on electrophoretic velocity …  Read more

Scott, Marilyn (Supervisor2)  Read more

The primary purpose of this study is the exploration of the theoretical and critical framework of media education. The major paradigms used as rationale for the study of media embody views of media as agents of cultural decline that stress discriminating against the media; media as popular arts, stressing discriminating within the media; media as agents of communication, featuring the behavioral models of media studies; studying the media as representational or symbolic systems; and an exploration of the interaction between the self and the media and the question of whether and how media empower or oppress. Developments in the fields …  Read more

The present study evaluates the efficacy of self-hypnosis and its components--relaxation instructions and waking analgesia suggestions--for pain reduction in patients recovering from gallbladder surgery. Forty elective surgery patients were randomly assigned to one of the three experimental pain control procedures or to a standard treatment control group--preoperative teaching. The treatments were found to be equally credible and generated equivalent expectancies for success. Pain was assessed using multiple subjective and objective measures sampled across the postoperative period. Multivariate analysis of these data indicated that the experimental treatments were no more effective in diminishing postoperative pain than the control procedure. However, the …  Read more

An association has been observed between the catechol-O-methyltransferase (COMT) gene, the predominant means of catecholamine catabolism within the prefrontal cortex (PFC), and neuropsychological task performance in healthy and schizophrenic adults. Since several of the cognitive functions typically deficient in children with Attention Deficit Hyperactivity Disorder (ADHD) are mediated by prefrontal dopamine (DA) mechanisms, we investigated the relationship between a functional polymorphism of the COMT gene and neuropsychological task performance in these children. Furthermore, since methylphenidate (MPH), the primary pharmacological drug in ADHD, may exert its effects, at least in part, through PFC dopaminergic pathways, we investigated the relationship between the …  Read more

Extending conjugation in 2-dimensions: Synthesis and characterization of multidentate monomers Over the past decade pi-conjugated organic polymers have attracted considerable attention because of their desirable characteristics similar to plastics (e.g., mechanical flexibility, simplicity and low-cost processing, etc.) as well as their interesting electronic/optical properties. The potential use of these materials in molecular electronics provides impetus for the development of new and modified pi-conjugated polymers. To that end, we propose to increase the dimensionality of pi-conjugation through formation of a two dimensional polymer. The synthesis of tri- and tetra-dentate monomers, which were designed for their predicted ability to form continuous conjugated …  Read more

The work presented in this thesis represents a contribution to the area of modeling of the transport and fate of herbicides applied to cropped fields, and was part of a larger research effort geared towards better management of herbicides. The main objective of this thesis was to develop a graphical user interface (GUI) for PESTFADE, a process-based mathematical model of pesticide transport and degradation, and to provide documentation for the execution of PESTFADE. The model simulates changes in pesticide concentration at different depths in the soil, based on relevant physical, chemical, biological and meteorological factors. PESTFADE is considered to be …  Read more