McGill University Thèses et mémoires par auteur commençant par Y

This study was directed at elucidating the structural and functional characteristics of legume protein isolates with different microstructures. Protein isolates with different microstructures (crystalline and amorphous) were prepared from four varieties of Phaseolus beans; white kidney bean and navy bean (P. vulgaris), and large lima and baby lima beans (P. lunatus). The protein isolates were subjected to tryptic hydrolysis at various time intervals, and the effect of hydrolysis on the functional properties of the protein isolates was studied, using bovine casein as control. Reversed phase HPLC with UV detection was used to generate peptide maps of the tryptic hydrolysates, and …  Lire la suite

The reactions of the early and intermediate stages of protein glycation were studied using bovine serum albumin and hen egg white lysozyme as model proteins, and D-glucose and D-fructose as model reducing sugars. The reactions were studied under low moisture and limiting sugar conditions in the presence and absence of oxygen in a closed system. Several analytical methods, including the fluorescamine assay, total Maillard fluorescence and solubility measurement, size exclusion chromatography, and electrospray ionization mass spectrometry were used to follow the glycation reaction. The effect of glycation on the structure of proteins was also studied by electrospray ionization mass spectrometric …  Lire la suite

Immigration and increasing cultural diversity in the West have become intense points of political contestation. In light of this, scholarly arguments and culturally inspired populist movements have arisen in the West to respond to immigration and diversity. This thesis shall argue that the Western liberal state has a fundamental commitment to neutrality-proceduralism, a commitment that severely limits the pace of change required to address the cultural or religious disputes at hand and makes predicating the acceptance of immigrants into liberal states on the basis of culture an unattractive proposition. It therefore follows in two crucial steps that: 1) the Western …  Lire la suite

While the use of microbial model systems in experimental evolution has made great contributions to our understanding of evolutionary processes, technological limitations and the problems of transparency they cause continue to inhibit their use in understanding even the most basic evolutionary phenomena. Conventional mathematical models are too constraining in that the range of genotypes and fitnesses must be designated at the outset, and so such models cannot be used to describe truly open-ended systems. In this thesis, I use Artificial Life technology to investigate patterns and mechanisms of evolution over short and long periods of time in a simulated chemostat-type …  Lire la suite

La technique de transduction du signal colorimétrique a été largement appliquée pour la détection d'analytes biologiques. Plus précisément, la lecture colorimétrique pour la détection d'agents pathogènes infectieux gagne en popularité dans les points de soins/besoins, en raison de ses caractéristiques remarquables, telles que sa haute sensibilité, sa facilité d'analyse et d'interprétation, ses exigences minimales en matière de formation et son prix abordable. En outre, la lecture colorimétrique facilite l'intégration avec le test d'amplification isothermique médiée par une boucle (LAMP), qui est une alternative populaire au test de référence qu'est la réaction en chaîne par polymérase (PCR) pour la détection des …  Lire la suite

Les mutations du gène actinine-4 sont associées avec la glomérulosclérose focale et segmentaire (FSGS) héréditaire chez l'humain. Nous avons démontré que la mutation actinine-4 K256E est mal dépliée et entraîne une agrégation de la protéine et sa dégradation dans les cellules glomérulaires épithéliales (GEC) in vitro. La mutation est associée à une protéotoxicité, i. e. à une activation du stress du réticulum endoplasmique (ER) et à un étranglement du protéasome. Dans cette étude, nous examinons si de petites molécules peuvent améliorer le repliement et les fonctions du mutant actinine-4 K256E, et deuxièmement si le processus de l'autophagie est induit par …  Lire la suite

Yaffe, Mark John (Supervisor2)  Lire la suite

In Caenorhabditis elegans, two mutations that affect mitochondrial electron transport chain subunits (isp-1 and nuo-6) result in increased mitochondrial reactive oxygen species (mtROS). These mutations cause a significant increase in lifespan relative to the wild type. Treatment with the pro-oxidant paraquat (PQ) can also significantly increase wild type lifespan, but is not additive to the lifespan of the two mutants. Using gene arrays, we determined a large overlap of differentially expressed genes between isp-1, nuo-6 and PQ treatment. These and other results are contrary the Free Radical Theory of aging and suggest that increased levels of mtROS act as a …  Lire la suite

Rationale. In Quebec, 6.2% of all Mycobacterium tuberculosis (TB) isolates from Canadian-born patients are resistant to pyrazinamide alone (mono-PZA-R). Over 90% of mono-PZA-R isolates in Quebec have been characterized by a specific and unique mutation in the pncA gene. The unusually high prevalence of mono-PZA-R disease and its associated mutational profile in Quebec provided an exceptional opportunity to study the epidemiologic and clinical significance of mono-PZA-resistance in patients with active TB. Methods. 67 patients with mono-PZA-R TB diagnosed between 1 Jan 1990 and 31 Dec 2000 were compared to 211 randomly selected patients with pan-sensitive (Pan-S) isolates diagnosed within the …  Lire la suite

Maioni, Antonia (Supervisor)  Lire la suite

Complementary hydrogen bonding is a powerful tool to control the solid-state packing of organic semiconductors. The supramolecular structure of organic semiconductors is a key parameter in determining their performance in organic electronic devices. In this thesis, we study the synthesis and characterization of organic donor and acceptor materials with an integrated three-point complementary hydrogen-bonding functionality with extended p-conjugation. The structures presented include pi-extended naphthalenediimide (NDI) based and dipyrrolopyridine (P2P)-based small molecules and polymers with lowered band gaps, which is desirable for applications in organic photovoltaic devices. Additionally, the pi-extended derivatives of P2P and NDI presents an opportunity to fine tune …  Lire la suite

The band gap and the supramolecular structure of organic semiconductors (OSCs) are two key factors influencing their performance in optoelectronic devices. Complementary hydrogen-bonding is a powerful interaction for controlling the supramolecular structure of OSCs. Recently, our lab showed that such hydrogen-bonding between donor and acceptor OSCs (bicomponent OSCs) also affects the band gaps of the donor and acceptor through a polarization effect, however the effect was weak. We thus sought a way to dramatically enhance this effect and exploit it as a tool in the design of bicomponent OSCs.In this thesis, we study charge-transfer complexes assembled via unidirectional two-point complementary …  Lire la suite

Cette recherche examine Deutéro-Isaïe 42:14 et 49:15 pour démontrer que ces deux passages se réfèrent à une métaphore maternelle. La plupart des sources secondaires ont négligé l'aspect maternel de YHWH dans ces versets. Cette recherche réexamine les problèmes interprétifs et exégétiques qui ont été utilisés autrefois comme des arguments contre les aspects maternels de YHWH, tel que ce qui constitue comme une métaphore et comment les lieux communs associés peuvent affecter la langue de la maternité. En montrant que l'imagerie maternelle est attribué à YHWH, cette recherche met en évidence l'importance de considérer YHWH comme comme étant imagé dans les …  Lire la suite

Le contrôle post-transcriptionnel, qui agit au niveau de l’ARN messager (ARNm), est un déterminant essentiel de l'expression des gènes, et comprend des processus tels que la traduction et la localisation de l'ARN et est le focus de cette thèse. Cette régulation est en partie dictée par les caractéristiques des régions non-traduites (UTRs) 5’ et 3’ de l’ARNm et des éléments cis qu’ils hébergent.Le contrôle de la traduction peut avoir lieu à l’étape d’initiation où la structure 5 'cap de l’ARNm est reconnue par eIF4E, dont l’activité peut être modulée par la protéine de liaison eIF4E (4E-BP), un répresseur de la …  Lire la suite

This thesis is about how medical knowledge is constructed by staff for patients and their families in a Japanese 'comprehensive care' facility for the treatment of epilepsy (the JEC). The thesis sets out to explain the possible reasons for differences between the number of surgeries of epilepsy performed at the JEC and the number performed in a Canadian institute. I will argue in the thesis that the fundamental difference between the two institutes lies in cross cultural and cross institutional differences in the uses and interpretations of the polysemic phrases 'comprehensive care' and 'quality of life'. They are ideological constructs …  Lire la suite

Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis. These cells have the unique ability to self-renew, to maintain a reserve of undifferentiated germ cells, and differentiate to continuously support long-term spermatogenesis. Thus, SSCs are important cells for male fertility restoration technologies. SSCs are maintained in a specialized microenvironment, in contact with testicular somatic cells and other germ cells. Communication amongst this cell society is believed to balance the SSC fate decision to self-renew or differentiate, to avoid over-proliferation or stem cell depletion. However, the secreted factors mediating this communication network are not completely known. Wnt signalling has been shown …  Lire la suite

This MA thesis studies the significance of the nineteenth-century British literary tradition of Gothic vampirism. The first half of the thesis surveys the modern image of Gothic vampires developed by Lord Byron in The Giaour (1813) and "Fragment of a Novel" (1819), by John William Polidori in his novella The Vampyre (1819), and by Abraham "Bram" Stoker in Dracula (1897). At the beginning of the nineteenth century Byron and Polidori reinvented the Gothic vampire as a callous, cunning, but always charismatic predator, and at the end of the century Stoker reinforced the same image by portraying his vampire-protagonist Count Dracula …  Lire la suite

Il est bien connu que la tension artérielle (TA) chute pendant le sommeil nocturne et monte pendant la journée. Ce rythme diurne s'explique en partie par les effets du sommeil et les changements posturaux sur la tension artérielle (TA). Il est également rapporté qu’un rythme circadien endogène de TA contribuerait à cette variation diurne. Le but de la présente étude est de préciser la contribution du système circadien endogène, l’effet de siestes et des changements de posture sur la variation de TA au cours de la journée. Onze jeunes adultes en bonne santé (âgés de 22,6 ± 3,4 ans, 1 …  Lire la suite

Guevara, M. R. (Supervisor)  Lire la suite

The aim of this Master's thesis was to examine the effects of leg andback strength, and trunk isometric endurance on lifting movementpatterns of females. Thirteen healthy females were recruited toparticipate in two consecutive sessions. Heart rate and whole-bodykinematic, kinetic and electromyographic (EMG) data were recordedduring lifting a 15 kg box from a floor level in series of bouts untilexhaustion. The first and last bouts of the task were analyzed. Resultsshow no significant change in lifting coordination with fatigue, mainlyattributed to inter-individual variability in lifting techniques. We foundsignificant relationships between measures of hip-back inter-jointcoordination and of strength of the hips and …  Lire la suite

Les cellules solaires à pérovskite (PSC), présentées pour la première fois en 2009, sont apparues comme une alternative potentiellement peu coûteuse et évolutive aux cellules solaires au silicium cristallin. Les PSC tirent leur nom de la couche absorbante de la structure cristalline de la pérovskite ABX3, où A est un cation monovalent, B un cation divalent et X un halogénure. Lors de l'absorption de la lumière, les électrons et les trous photogénérés dans la couche de pérovskite sont extraits par la couche de transport d'électrons (ETL) et la couche de transport de trous (HTL), respectivement. L'une des lacunes les plus …  Lire la suite

This thesis is one step in defining the parameters of archaeology in an aboriginal context. It is designed to be a practical guide for imagining the past from an internalist perspective because archaeological methods offer the opportunity to represent antiquity that is simultaneously rational and familiar. However, an ancillary objective is to utilize symbols from antiquity as markers of modern Indian identity. Archaeology appeared on the radar of First Nations because their growing populations demand housing and economic opportunities. Recent settlement of land claims has brought large tracts of land under the control of Native people. Archaeological sites, by their …  Lire la suite

Cette étude a exploré l'impact de la guerre sur la santé mentale, physique et sociale de six jeunes adultes ukrainiens (cinq femmes et un homme) résidant à Montréal, âgés de 18 à 30 ans (H = 26,33, É.-T. = 3,61) qui ont immigré au Canada dans le cadre du programme d'autorisation de voyage d'urgence Canada-Ukraine (AUEU) en raison du conflit en Ukraine. L'objectif était de documenter et d'analyser les effets de la guerre et du processus d'immigration découlant de l'invasion russe de l'Ukraine en 2022. Cette thèse explore les données d'entrevues approfondies recueillies au cours d'un programme complet de recherche-création …  Lire la suite

Proteins are the foundation of most of the dynamic and modular molecular machines that execute many processes in living cells. The dynamic properties of these machines are central to their function, yet also hinder our ability to study the composition, distribution and regulation of protein complexes. To improve the study of molecular machines involved in cell division, I developed new quantitative methods that incorporate the power of mathematics and physics to study the structural organization and dynamic properties of protein complexes that were previously inaccessible by traditional means. First, I developed a new method to predict the conformations of protein …  Lire la suite

During the past two decades, a rapid growth of interest in the search for high temperature materials has accompanied developments in aero-engines, rockets, ballistics, combustion chambers, gas turbines, ram-jets and other novel propulsive mechanisms. The aim of this thesis is to make available to fellow students, engineers and applied physicists a general survey plus the extra data obtained at McGill, which would be useful as an introductory reference in the subject. [...]  Lire la suite

Introduction. Preliminary studies found that discordance between the patients' and physicians' assessments of disease activity in systemic lupus erythematosus (SLE) exists. We investigated the factors associated with discordance and explored the impact of discordance on medication adherence and complementary/alternative medicine (CAM) use. Methods. Part I investigated the factors associated with discordance, defined as the patient visual analog scale (VAS) minus the physician VAS for global disease activity. Data were extracted from the Montreal General Hospital Lupus Registry. Potential covariates included the Medical Outcomes Studies SF-36, the Systemic Lupus Activity Measure (SLAM), and a lupus damage index. The first visit data …  Lire la suite

Previous studies have suggested that sympathetic sprouting in the periphery may contribute to the development and persistence of sympathetically-maintained pain in animal models of neuropathic pain. The purpose of this thesis was to examine morphological changes in the cutaneous innervation in rats after chronic constriction injury (CCI) to the sciatic nerve. More specifically, this study addresses the question of whether sympathetic fibres sprout de novo into the upper dermis of the rat hindpaw skin after CCI of the sciatic nerve. We also determined changes in peptidergic sensory innervation following CCI. At several periods post-injury, hind paw skin was harvested and …  Lire la suite

There is a growing body of evidence that Canadian consumers have concerns about the impact of agricultural production on the health of the environment and on society. This study investigates the preferences of rural and urban consumers in Quebec for food attributes that provide environmental, health, and social benefits. The choice modeling technique was employed to estimate the implicit prices of specific food attributes and willingness to pay (WTP) values for alternative food products. Results suggest that rural consumers place higher value on environmental benefits and have higher social existence values than urban consumers, while urban consumers value health benefits …  Lire la suite

A survey was undertaken to assess the knowledge, attitudes and practices, with respect to malaria, of 300 women from six randomly selected rural communities in Central Ethiopia from December 1991 to February 1992. Eighty-five per cent were able to recognize one or more of the common symptoms of malaria. Transmission was generally misunderstood and only 23% believed it could be prevented. More women preferred to obtain antimalarials from government clinics than from private drug shops, mission clinics, unofficial injectors, open markets or from leftover sources. Children under five were identified as the most malaria-vulnerable group and given priority for treatment. …  Lire la suite

A student's proficiency in a language is usually assessed by measuring his competence in understanding, speaking, reading, and writing. Foreign language training programs differ in the emphases placed on the development of each of these four basic language skills. Some of these differences are directly related to the specific needs of particular student populations while others are related to the method of instruction the teacher has adopted. [...]  Lire la suite

Norma Ybarra (Supervisor2)  Lire la suite

Understanding the variations of precipitation process in time and in space is essential for the planning, design, and management of various water resources systems. Recently, climate change impacts on precipitation have been recognized as one of the most critical issues for water management in many regions around the world. The present study was therefore carried out in order to develop better methods for improving the accuracy of rainfall estimation at a gauged or ungauged local site in the context of a changing climate. This study can be divided into five main parts.The first part of the present research deals with …  Lire la suite

Contexte : La solitude à l'adolescence est un problème de santé publique de plus en plus préoccupant, associé à des effets néfastes sur la santé mentale et physique. Bien que l'exposition aux espaces verts ait été identifiée comme un déterminant environnemental potentiel du bien-être social, les preuves de son impact supposé sur la solitude des adolescents restent limitées. Cette étude a examiné l'association prospective entre l'exposition aux espaces verts pendant l'enfance (de 5 mois à 10 ans) et la solitude au début de l'adolescence (de 10 à 13 ans), en tenant compte d'une série de facteurs confondantes, et a exploré …  Lire la suite

Four novel aromatic difluoride compounds were synthesized for use as monomers in nucleophilic aromatic displacement polymerization reactions. Attempts were then made to polymerize these monomers with a series of bisphenols, using potassium carbonate as a base, in a dipolar aprotic solvent as in equation 1. eqalign qquad{& rm K sb2CO sb3 cr rm F{-}Ar{-}F + HO{-}Ar{-}OH quad& rm quad longrightarrow quad quad bigl(O{-}AR{-}O{-}Ar bigr) sb{n} cr& rm Dipolar aprotic cr& rm solvent cr& rm 160-195 sp circ C cr} eqno(1) sing the reaction above, several novel poly(aryl ether)s have been produced and some of their physical properties, such as glass …  Lire la suite

Cette thèse explore les expériences quotidiennes des migrants vivant en Équateur, en mettant l'accent sur la manière dont les soins, la survie et la résistance émergent dans des contextes de précarité juridique et économique, ainsi que de vulnérabilité liée au genre et à la négligence institutionnelle. À travers à un travail ethnographique multi-situé, comprenant des conversations en personne et à distance, des pratiques de dessin collaboratif et des relations à long terme avec des interlocuteurs migrants, cette thèse cherche à dévoiler (au sens littéral et métaphorique) les complexités de la migration, de l'incarnation et de la vie transnationale. Plutôt que …  Lire la suite

Hatami, Hamed (Supervisor2)  Lire la suite

La protéine du rétinoblastome (pRB) inhibe la progression du cycle cellulaire en s’associant aux facteurs de transcription de la famille des E2Fs. L’importance de pRB dans le cycle cellulaire est démontrée par le fait que sa fonction est perdue dans plusieurs types de cancers chez les humains, résultant en une prolifération cellulaire incontrôlée. Notre recherche se concentre sur l’étude de facteurs qui influencent la prolifération et la survie de cellules déficientes en pRB, en utilisant Drosophila melanogaster et sa voie pRB/E2F simplifiée comme système modèle. Des études antérieures ont démontré que la voie de signalisation EGFR/Ras joue un rôle important …  Lire la suite

The effect of the key physiological parameters on the production of solvents in the acetone-butanol fermentation using the anaerobic bacterium Clostridium acetobutylicum was examined in this work. The theoretical solvent yield was calculated based on expressing stoichiometric relationships between the substrate and the products of the process. The maximum theoretical yield under the acceptable process conditions was established ranging from 38.6% to 39.9%. A linear correlation was established between the production of solvents and gases which varied with the mixing rate of the fermentation system. Elevated hydrogen partial pressure affected the metabolism of C. acetobutylicum resulting in increased butanol and …  Lire la suite

In recent years, autonomous driving has become one of the most studied topics in the field of computer vision and machine learning. Various problems have been studied, such as object detection, motion prediction, or even collision detection. This thesis focuses on the specific problem of predicting the motion of agents on the road based on their surroundings. Most modern autonomous driving solutions require costly sensors such as LiDAR. This thesis attempts to predict vehicle trajectories using only RGB images captured by an ego vehicle, bypassing the need for costly sensors. We utilize both pose and depth estimation values to predict …  Lire la suite

Various sources on Kazakh history demonstrate that a Kazakh culture was generated out of the predominantly pastoral experiences of its people. For centuries, Kazakh communities were engaged in a definite set of practices prescribed by pastoralism. Firmly incorporated into the all-Union structure of Soviet republics, Kazakhstan made an impressive transformation from a predominantly pastoral to an agroindustrial region with one of the most vibrant economies in Central Asia. Sovereignty in 1991 pushed the historic trajectory of the Kazakh nation further ahead, prompting its citizens to engage in self-reflection, and attuning their collective memories to a new set of social and …  Lire la suite

Les atlas cérébraux sont des outils essentiels pour l'interprétation standardisée de la structure et de la fonction cérébrale autant en recherche qu'en imagerie neurologique clinique. Les atlas histologiques multimodaux permettent la visualisation sans précédent des détails cytoarchitecturaux et neurochimiques du cerveau humain. Les formats numériques, déformables et intégrés des atlas histologiques sont de plus en plus demandés pour suivre les avancées en imagerie IRM haute résolution de la structure et de la fonction cérébrale. Cependant, le cerveau humain subcortical s'est révélé difficile à cartographier efficacement en se basant uniquement sur les données IRM en raison de sa géométrie compacte et …  Lire la suite

Local participation in environmental decision making processes is a recognized need if the goals of sustainable development are to be met. Spatial information is an important part of environmental decision making, but so far, technical barriers have prevented effective public participation in spatial data management and analysis. These barriers need to be overcome if participants are to take part in a decision making process in a manner that is both fair and competent. The study was undertaken to quantify land cover change in a particular region and, through this exercise, to determine what the practical barriers to public participation in …  Lire la suite