McGill University Thèses et mémoires par auteur commençant par S

Many advances have being made in understanding the pathological processes in Alzheimer's Disease (AD) and in testing therapeutic strategies to stop disease progression. It has become clear that neuroinflammation plays a main role in AD. Evidence is being gathered from experimental, epidemiological and clinical trials studies that this process happens even earlier, in stages where pathology is present but no symptoms are detected. Even though the late, plaque-associated central nervous system (CNS) inflammation is well characterized, many questions remain regarding the early inflammatory process. Understanding this event is important to develop biomarkers to identify those at risk for AD and …  Lire la suite

Wood Poles are extensively used in North America as supports for electric distribution lines. On average, wood poles have a service life of 40 years with a replacement cost of approximately $2000. Since the distribution network is of relatively recent construction, maintenance and replacement costs have been relatively small compared to the total number of poles in service. The goal of this thesis is to use the FORM/SORM algorithm to evaluate the reliability of a single pole and the results obtained when applied to a sample of 887 wood poles inspected in the field. The procedure was also applied to …  Lire la suite

Titone, Debra Ann (Internal/Cosupervisor2)  Lire la suite

Benoit, Champagne, (Internal/Cosupervisor2)  Lire la suite

The rapid growth of medical sciences and technologies created the need to manage data generated by sophisticated medical equipment (e.g. lab results, vital signs, etc.). This class of equipment, especially in the modern Intensive Care Unit (ICU), emits large quantities of latient data which medical staff usually records on log sheets. This thesis presents a database design that allows abstract definition of data types, and offers a unified view of data during the development phase, distinct levels of data management and a higher degree of system flexibility. This database model is an implementation of a database for a Patient Data …  Lire la suite

During prolonged EEG monitoring of epileptic patients, the continuous recording may be marked where seizures are likely to have taken place. Several methods of automatic seizure detection exist, but few can operate as an on-line seizure alert system. Proposed is a seizure detection system that can be used in real-time to alert medical staff to the onset of a patient seizure and hence improve clinical diagnosis. Proposed is a system based on the seizure probability of a section of EEG. Final operation features a user-tuneable threshold to exploit the trade-off between sensitivity and detection delay and an acceptable false detection …  Lire la suite

B+/- mesons are reconstructed via two decay modes: B+/-→ccK+/- and B+/-→J/yK+/- from data collected by the CDF experiment, corresponding to an integrated luminosity of 109 pb-1. An unambiguous B+/-→J/yK+/- signal is observed; however, the B+/-→ccK+/- signal was not of sufficient quality to allow for the determination of the relative branching ratios of the two processes.  Lire la suite

An equal-order co-located Control Volume Finite Element Method (CVFEM) for the prediction of multidimensional, incompressible, viscous fluid flow problems has been formulated. CVFEMs provide the geometric flexibility traditionally associated with finite element methods. In addition, their control volume based formulation facilitates physically meaningful interpretation of the resulting discretization equations. In the proposed CVFEM, the calculation domain is divided into three-node triangular and four-node tetrahedral finite elements in two- and three-dimensions, respectively. Each element is further subdivided in such a way that upon assembly of all elements, complete control volumes are formed about each node in the calculation domain. Interpolation functions …  Lire la suite

Marino, Faleh Tamimi (Supervisor2)  Lire la suite

L'intégrité du cytosquelette cellulaire est essentielle pour les fonctions physiologiques multiples requises pour le maintien de l'homéostasie tissulaire tel que la morphologie, la polarité, la contractilité, la division, la locomotion, ainsi que le trafic intracellulaire de molécules de signalisation. La régulation du cytosquelette est médiée par un ensemble collectif de protéines de liaison et de réticulation de l'actine, qui servent de médiateur à la ramification des filaments d'actine en réseaux étroitement organisés. Une classe majeure de protéines d'agrégation d'actine est représentée par la famille Fascin, qui comprend Fascin-1, puis Fascin), -2 et -3.Fascin fonctionne comme une protéine de liaison d'actine …  Lire la suite

Intergovernmental conflicts in Canada have intensified over the construction of new interprovincial pipelines designed to transport the country’s abundant oil and gas reserves to consumer markets. This thesis examines the intricate intergovernmental interactions at the policy, governance, constitutional, and regulatory levels in the pipeline context, using the Trans Mountain Expansion Project as a case study. It seeks to mitigate opposition between governments by proposing that courts be equipped with additional constitutional tools to promote cooperative behaviour. Specifically, this thesis advocates for incorporating a principle of federal loyalty into Canadian constitutional law. This principle could offer a normative foundation for the …  Lire la suite

Extremely huge quantities of mined ore materials are processed annually to obtain the various types of minerals being the barebones of industry. Impounding the waste materials (tailings) of the mined minerals behind a raised embankment is the major and most common method used for the disposal of theses materials. Due to its execution simplicity and low cost, the upstream raising method has been the most common method used for retaining the disposed tailings in spite of being the most failure-vulnerable one. The sophisticated hydromechanocal behavior of the upstream tailings disposal facilities (UTDFs) during the staged construction makes the traditional approaches …  Lire la suite

Kry, Paul (Internal/Cosupervisor2)  Lire la suite

Colletotrichum coccodes (Wallr.) Hughes, a foliar pathogen of velvetleaf, is being developed as a bioherbicide. Formulation of living organisms for use as pest control products presents unique problems. This research has achieved the development of an adequate formulation of the pathogen by using kaolin clay or talcum powder (1:2.79 wt/wt) as the fillers to dry conidia. Formulated C. coccodes conidia stored at 4, 30C, or at room temperature in bags permeable to oxygen remained viable and able to infect velvetleaf plants at least six months in storage. Various reported germination stimulants increased germination of formulated conidia, although not significantly, whereas …  Lire la suite

Hedgehog (Hh) est un morphogène diffusible dont la voie de signalisation régule de nombreux processus cellulaires nécessaire à la mise en place et le développement des tissues. Les dérégulations de la voie de signalisation Hh sont la cause de nombreux syndromes et maladie, notamment certain cancer tel des médulloblastome ou des carcinomes basocellulaire. En l’absence d’Hh, la protéine kinase A (PKA) phosphoryle le facteur de transcription Cubitus interruptus (Ci) chez Drosophile / Gli chez les vertébrés, induisant son clivage partiel par le protéasome et permettant son activité répressive, inhibant l’expression des gènes cibles de Hh. Chez la Drosophile uniquement, lors …  Lire la suite

The number of freeze-thaw cycles is expected to grow with climate change in northern latitudes, prompting a growing emphasis on mitigation strategies in the masonry construction industry in Canada. While also addressing the stricter energy requirements in recent decades, masonry construction has seen a shift from traditional thick and solid masonry walls to energy-efficient ventilated cavity-walls, meant to promote drying and also improve the building’s energy efficiency. Despite these advancements, the growing environmental awareness movement of the 1970s has caused the rise in popularity of reclaimed brick used in modern construction, yet these bricks are more susceptible to freeze-thaw damage. …  Lire la suite

Determining the optimal long-term operating policy of a multi-reservoir power system requires solution of a stochastic nonlinear programming problem. For small systems, the solution can be found by dynamic programming, but for large systems no direct solution method exists yet, so that one must resort to mathematical manipulations to solve the problem. This thesis presents a very efficient procedure for the case where high correlation exists between the state variables. It consists in performing principal components analysis on the trajectories to find a reduced model of the system. The reduced model is then substituted into the operating problem and the …  Lire la suite

The behavior of the shear layers separating from a rotationally oscillating cylinder was investigated using hot-wire anemometry and smoke-flow visualization in a wind tunnel at a Reynolds number of 3700. The cylinder was oscillated at small peak-to-peak amplitudes and frequencies lower than and near the natural Kannan frequency. The shear layers responded in a way such that their characteristics were modified depending on the frequency and amplitude of oscillation. Results showed that as the oscillation frequency increased, the shear layers were highly disturbed, the shear-layer instability was promoted upstream and its frequency increased, the shear-layer vortices formed antisymmetrically and closer …  Lire la suite

Tabrizian, Maryam (Supervisor2)  Lire la suite

Douglas, W. J. M.  Lire la suite

Who am I in literacy teaching? The purpose of the present research was to delve deeper into the question of identity, to uncover in literacy teachers the connection between the who (who they are) and the what (literacy teaching). The who, elusive and intangible, is difficult to name or define; Hannah Arendt (1998) writes that "the moment we want to say who somebody is, our very vocabulary leads us astray into saying what he [sic] is" (p. 181). But with guidance from Arendt, Parker J. Palmer and Margaret L. Dobson, the who was understood as unique, omnipresent, unchanging in its …  Lire la suite

This thesis presents several design experiments for high-performance power-efficient asynchronous circuits. In Chapter two we present a new asynchronous pipeline logic family with improved latency and throughput compared to several other asynchronous pipeline circuits. The channels between pipeline stages use data encoding and a small set of minimum-delay timing constraints that permit modular design with few dependencies on technology and layout. We develop circuit blocks that implement linear pipelines as well as forking, joining and data-dependent decisions. An implementation in 0.18mum CMOS exhibits a latency of 56ps per pipeline stage and throughput of 4.8-giga data item per second (GDI/s) in …  Lire la suite

Processus naturel complexe, l'érosion du sol est fréquemment exacerbée par les activités anthropiques telles le défrichage, l'agriculture, la construction, et l'exploitation minière à ciel ouvert. Une cartographie précise du type et de l'intensité d'érosion du sol peut s'avérer un outil efficace dans une lutte contre l'érosion. Les présentes recherches visèrent l'utilisation de SIG et de données de télédétection dans la localisation et l'identification de divers types d'érosion sur une aire de grande étendue (4,511.8 km2) en Iran. L'étude s'échelonna sur trois étapes: (i) un modèle altimétrique numérique (MAN) d'une résolution de 10 m servit à créer des plans de pente …  Lire la suite

La maladie de Parkinson (MP) est une maladie neurodégénérative courante associée à des déficiences motrices, cognitives et affectives. Il est important de noter que les symptômes non moteurs peuvent avoir un impact plus important sur la qualité de vie que les symptômes moteurs. La stimulation cérébrale profonde (SCD) est un traitement neurochirurgical de plus en plus utilisé en MP, lorsque les symptômes moteurs ne peuvent plus être suffisamment contrôlés par la médication. Le profil neuropsychologique d'un patient contribue à l'évaluation du risque préopératoire et joue un rôle central dans l'évaluation de la candidature à la SCD. La déficience cognitive préexistante …  Lire la suite

Ngadi, Michael O. (Internal/Supervisor)  Lire la suite

Reverse transcription in HIV-1 (human immunodeficiency virus type 1) is initiated from a tRNA, tRNALys3, that is annealed to the primer binding site (PBS) in the 5' region of viral RNA. This tRNA, along with the other major tRNALys isoacceptors, tRNALys1,2 , is selectively packaged into HIV-1 during its assembly. The formation of a tRNALys packaging/annealing complex is believed to involve the interaction between a Gag/GagPol/viral complex with a lysyl-tRNA synthetase (LysRS)/tRNALys complex, with Gag interacting specifically with LysRS, and GagPol interacting with both Gag and tRNALys. In fact, Gag particles alone will package LysRS, but GagPol, which binds tRNA …  Lire la suite

Community-based adapted physical activity programs, such as Adaptavie and Viomax, can benefit people with disabilities, however there is a lack of evidence-based tools to support kinesiologists' training in those programs. This study aimed to co-create and evaluate the implementation of physical activity training resources to meet the needs of Adaptavie and Viomax for improved staff training. The methodology comprised two phases. Phase 1 involved an integrated knowledge translation approach with a working group (n=8) consisting of staff, kinesiologists from Adaptavie and Viomax, and researchers. Four online meetings were conducted to discuss needs, co-create training modules, and assess usability. Phase 2 …  Lire la suite

The objective of this work is to design a system for the visualization of geographical terrain in three dimensions. The input of such a system is the contour map of the region to be visualized. Several approaches to solve this problem can be found in the literature. Our approach is based on surface reconstruction or interpolation. We achieve the reconstruction of the terrain surface by pairwise triangulation of map contours in adjacent height levels. The large data size in this application dictated the use of an optimal triangulation algorithm. The algorithm we employed (by G. Toussaint) runs in $O(n(1+t sb0)$ …  Lire la suite

Yule, W. N. (Supervisor)  Lire la suite

The altered protein expression and activity of receptor tyrosine kinases (TK) are implicated in the progression of various types of cancers. One such dysfunction is the overexpression of the epidermal growth factor receptor (EGFR) that correlates with aggressive tumor progression and poor prognosis. On the other hand, c-Src non-receptor tyrosine kinase is overexpressed and activated in a large number of human malignancies and has been strongly linked to progression to distant metastases. c-Src-induced phosphorylation of EGFR is required for EGF-mediated mitogenesis, tumorigenesis and tumour invasiveness. Thus we surmised that molecules termed "combi-molecules" designed to block both EGFR and c-Src should …  Lire la suite

Cecere, Renzo (Supervisor2)  Lire la suite

Joos, Geza (Internal/Cosupervisor2)  Lire la suite

Cystinuria is an autosomal recessive disorder of the kidneys and intestine with defective luminal transport of cystine and other dibasic amino acids (ornithine, arginine, and lysine). Three phenotypes have been described, based on urinary excretion of these amino acids in obligate heterozygotes: Type I (silent carriers); Type II (moderate elevation); and Type III (mild elevation). The SLC3AI (D2H) protein has been shown to enhance cystine reabsorption and mutations in D2H have been reported in cystinuria. The aims of this study were to characterize D2H gene structure and to identify mutations in Quebec patients. The D2H cDNA was used to isolate …  Lire la suite

La modulation optique de la multiplicité multi-excitonique des nano-crystaux CdSe/ZnS obtenue par excitation d'états spécifiques démontre le potentiel d'application de ces matériaux dans le domaine de la logique optique, atteignant des taux de modulation de l'ordre de 1ThZ comme dicté par le taux de recombinaison d'Auger. Grâce à une méthode de pompage optique, une fonction « ET » a été réalisée avec des nanocrystaux de type CdSe/ZnS, mettant ainsi à profit les interactions multi-excitoniques uniques de ces nanocrystaux colloïdaux. Des techniques spectroscopiques pompe/sonde résolues en états quantiques ont été appliquées afin d'étudier les différences d'environnements excitoniques entre des points quantiques …  Lire la suite

Stein, Michael (Supervisor)  Lire la suite

In accordance with the two-signal model, optimal T cell activation can only occur in the presence of a primary antigen specific signal, provided by the T cell receptor, and a second co-stimulatory signal. The most potent co-stimulatory molecules identified to date are the CD28/CTLA-4 receptors with their CD80/CD86 ligands, found on T cells and antigen presenting cells (APC) respectively. Many studies have implicated the V-domain of CD80 and CD86 to be responsible for the direct interaction with CD28/CTLA-4. Conversely, few studies have shown that the C-domain CD80 is crucial for the interaction and ultimate suppression of T cell activation and …  Lire la suite

We investigate inequalities that can be viewed as generalizations of Hardy's inequality about the Fourier coefficients of a function analytic on the circle. The proof of the Littlewood conjecture opened a wide door in front of questions regarding possible generalizations of Hardy's inequality. The proof of the Littlewood conjecture was based on some constructions of bounded functions having particular properties. In 1993, I. Klemes investigated one of the constructions (we shall call it the algebraic construction) and proved what is called a mixed norm generalization of Hardy's inequality. It turns out that we can work with the same construction and …  Lire la suite

Professors have three main functions in universities: research, teaching and service. This study focuses on the teaching function. Effective teaching in higher education enhances students' learning while ineffective teaching can have detrimental impact on students' learning and their attitudes toward learning. In this regard, it is important that professors have the knowledge base for effective teaching, a base which is growing and changing rapidly. This requires that they engage in professional development activities to improve their teaching. Research suggests that professors are reluctant to dedicate time to improve their teaching. The main purpose of this study was to investigate the …  Lire la suite

Saroyan, Alenoush (Supervisor1)  Lire la suite

Lipase-catalyzed esterification and transesterification reactions of selected phenolic acids with lipids were investigated in organic solvent media. The esterification of linoleyl alcohol with dihydrocaffeic acid (DHA) in neat hexane medium resulted in highest esterification yield (EY) of 17% when a Candida antarctica lipase (Novozym 435) was used to catalyze the reaction. The use of co-solvents t-butanol and 2-butanone with hexane resulted in a dramatic increase in EY. The highest EY of 83% was obtained in hexane:2-butanone mixture of 85:15 (v/v) using Novozym 435; however lower EY (40%) was obtained when a lipase from Rhizomucor meihei (Lipozyme IM 20) was used. …  Lire la suite

En 2005, Simons et al. ont émis l'hypothèse d'un passage de la signalisation canonique à la signalisation non-canonique de WNT durant le développement du rein. L'échec de cette transition aurait pour conséquence le développement de kystes rénaux. Notre laboratoire a montré que la signalisation canonique de WNT est élevée pendant le développement du rein et est réprimée une fois la néphrogenèse accomplie dans les souris kystiques et de type sauvage. Nous supposons que la signalisation non-canonique de WNT pourrait être anormalement régulée dans les cas de polykystose rénale type dominant (ADPKD). Nous avons étudié le rôle de la voie non-canonique …  Lire la suite

Les asthmatiques se caractérisent par un remodelage des voies respiratoires, incluant des changements dans la matrice extracellulaire et une augmentation de muscle lisse des voies respiratoires (MLVR). Aussi, les muscles lisses des asthmatiques ont une contractilité augmentée. Récemment on a montré qu'en changeant la matrice extracellulaire sur laquelle les muscles lisses sont cultivés, on peut affecter leur prolifération et l'apoptose. Mais on ne sait pas encore si la matrice extracellulaire peut affecter la contractilité des muscles lisses. Les muscles lisses ont été isolés des rats « Brown Norway » qui ont été sensibilisés avec l'ovalbumine (OVA) et ont été provoqués …  Lire la suite

Tagalakis, Vicky (Internal/Supervisor)  Lire la suite

Fibrillins constitute the major backbone of multi-functional microfibrils in elastic and non-elastic extracellular matrices. Proper expression, assembly and homeostasis mechanisms are central to the formation and function of these microfibrils. These properties are often compromised in pathological situations such as Marfan syndrome and other fibrillinopathies caused by mutations in fibrillins.While the developmental expression of fibrillin-1 and -2 has been intensely studied, fibrillin-3 is much less characterized in this regard. In this thesis, we analyze the developmental expression of human fibrillin-3 and compare it to that of other fibrillin isoforms. Fibrillin-3 is widely expressed in connective tissues of many organs as …  Lire la suite