McGill University Theses and dissertations by author name (Ç)

The biblical narrative of the meyalledot haᶜivriyyot (Exod 1:15-21) recounts the story of two heroic God-fearing midwives, named Shiphrah and Puah, who defy Pharaoh's order to kill Hebrew male infants. They are ultimately rewarded by God for their efforts and are given battim. From their portrayal in the biblical text and from the perspective of most commentators, the midwives are important figures who acted righteously. But who were they? And what exactly is their role in the Exodus narrative? This study will examine a large sample of mostly Jewish and some Christian interpretations of Exodus 1:15-21 from the ancient to …  Read more

WaIler, Harold (Supervisor)  Read more

Hagiography occupies a central place in the history of European culture, and yet despite this centrality, its reception as a significant cultural achievement has at times been undermined by a narrow critical hermeneutic, one that focuses largely on the debilitating flaws of the genre. The goal of this critical practice can be described as at once diagnostic and prescriptive, as scholars attempt to rid the canon of specious documents through rigorous textual and contextual analyses. It is my contention, however, that this critical winnowing, rather than rescuing some hagiographic documents from disrepute, is in fact limited by its failure to …  Read more

During the early months of 1965, the prolonged and contentious debate concerning constitutional amendment in Canada seemed to be drawing toward a satisfactory and definitive conclusion. Federal authorities had succeeded in preparing an amending formula acceptable to all the provincial governments, and with this formidable hurdle finally surmounted, the drive to "re-patriate" the constitution seemed to be assured of success. [...]  Read more

As far back as 1884, Loeffler (59) had directed attention to the haemolytic streptococci which were more or less constantly present in the throats of acutely ill scarlet fever patients. Lemoine (58), in 1895, found streptococci alone in 93 cases when examining the mucus from 117 throats in scarlet fever, while 14 cases had streptococci in association with other organisms. The absence ot streptococci in only 5 of 701 scarlet fever patients was reported by Baginsky and Sommerfeld (3), while Ruediger (88), examining 75 throats of patients ill with this disease, found that 64 showed streptococci alone, with pneumococci and …  Read more

Les textiles présentant des propriétés physiques, mécaniques et fonctionnelles améliorées sont recherchés pour les vêtements, les dispositifs portables et les textiles techniques. Pour minimiser les impacts de la production textile sur l'environnement et réduire les déchets textiles, des textiles capables d'autoréparer ses défauts et donc d'avoir une durée de vie prolongée ont été développés en incorporant des agents de réparation externes dans les textiles traditionnels. Cependant, de nombreuses stratégies d'autoréparation rapportées fonctionnent sur des échelles de taille limitées, nécessitent des produits chimiques complexes ou des solvants polluants, et présentent des problèmes environnementaux et sanitaires. Au contraire, les agents de réparation …  Read more

The case-crossover design is a new epidemiological method that evolved around binary exposures and the binomial distribution. We develop a new approach of data analysis for this design based on the actual exposure occurrence times, such as those available from computerized prescription databases. Assuming an exponential distribution for the inter-exposure onset times, we derive two new matched-paired estimators of the odds-ratio, one weighted the other unweighted. A simulation study demonstrates that both new estimators based on the exponential distribution are more efficient than the classical estimator based on the binomial distribution and that the unweighted estimator appears to be the …  Read more

Fong, Grace S. (Supervisor2)  Read more

Ultrafast electron diffraction (UED) provides direct, time-resolved access to atomic-level structural dynamics in molecules and materials. This thesis investigates ultrafast photoinduced dynamics in zinc phthalocyanine (ZnPc) thin films by combining UED with transient absorption (TA) spectroscopy, thereby linking structural rearrangements to electronic evolution. UED reveals a sub-ps structural response assigned to crystal dimerization, followed by a slower shear--twist motion on the 10 ps timescale. Correspondingly, TA shows long-lived excited-state absorption features that differ between ZnPc and fluorinated ZnPc. Both UED and TA also exhibit oscillatory components persisting up to 100 ps. Within a set of given experimental condition, these oscillations …  Read more

In recent years, video games have surged in popularity, attracting millions of players across platforms. Citizen science games (CSGs) leverage the processing power of gamers to solve computational and scientific problems. Borderlands Science (BLS) is a mini-game within the mass market game Borderlands 3 that turns multiple sequence alignment (MSA) problems into puzzles. Parallel research demonstrated that BLS players outperformed classical approaches solving small sequence alignment tasks. This study aims to analyze the strategic differences in player solutions in BLS as they gain experience. Through the many collected player solutions from players of different experience levels, we gained insights into …  Read more

Insect herbivory may be devastating for a crop. One important pest insect is the beet armyworm, Spodoptera exigua Hübner. This caterpillar causes damage to many different economically important horticultural and agricultural crops. However, in response to herbivore pressure, plants have evolved defenses that can act on the insect by affecting their behaviour, growth and/or mortality; all of which substantially decrease insect pest populations (Karban and Baldwin, 1997). Therefore, to study plant resistance, the model legume Medicago truncatula Gaertn was used. Different M. truncatula ecotypes (A17, A20, DZA045.5, DZA315.16, F83005.5, and TN1.11) were screened for resistance against caterpillars of the beet …  Read more

Many bacteria accumulate carbon stores as poly-3-hydroxybutyrate (PHB) when growth is limited but carbon availability is not. This stored carbon can then be utilized during conditions of limited carbon availability. The net PHB accumulation in the cell is dependent on the balance between PHB synthesis and degradation. Sinorhizobium meliloti accumulates PHB in the free-living stage but not in the symbiotic stage. The physiological role of the PHB cycle in S. meliloti is unknown. As a first step to understand the genetics of PHB degradation, transposon-generated mutants that were not able to use PHB degradation intermediates, such as 3-hydroxybutyrate and acetoacetate, …  Read more

The rapid progress of computer systems based on fine-grain multithreaded program execution models introduce both unique opportunities and challenges in the design and application of dynamic load balancing algorithms. This thesis presents a study of dynamic load balancing under the EARTH muitithreaded model. In this study, we have implemented a number of load balancing algorithms on the EARTH-SP testbed--a realization of EARTH model on the IBM-SP2 system. Our study has been carried out on both benchmark programs and a set of stress tests. The major results of this thesis include: (A) Demonstration that a load balancing algorithm is likely to …  Read more

Célébrité culturelle et diplomate, Pablo Neruda a visité la Chine deux fois dans les années 1950. Parmi les personnes qu’il a accueilies en Chine, Ai Qing, le poète acclamé du peuple, est rapidement devenu un ami avec Neruda. Centrée sur leurs rencontres dans les années 50, cette thèse prend comme point de depart les identités d’artiste et de politician de Neruda et d’Ai Qing, et soutient que la rencontre d’Ai Qing avec Neruda éclaire l’hétérogénéité de la création poétique d’Ai pendant une époque de crise nationale et de bouleversement sociaux. Enquêtant sur les conditions historiques qui ont rendu posible leur …  Read more

In searching for genetically-programmed responses to arsenic oxyanion exposure in plasmid-free bacterial strains, an arsenate-inducible Escherichia coli chromosomal operon was identified using a Mud I (lac Apr) transposable bacteriophage. The operon is induced by cellular exposure to arsenic and antimony oxyanions. The operon contains three cistrons that are homologous to the arsR , arsB, and arsC genes of plasmid-borne ars operons, coding for an arsenite/antimonite-inducible repressor, an inner membrane arsenite transporter, and an arsenate reductase, respectively. The E. coli chromosomal ars operon is functional in protection against arsenic toxicity, as mutants of this operon are hypersensitive to arsenic. To elucidate …  Read more

Les matériaux à base de carbone, tels que le graphène, les nanotubes de carbone (CNT) et l'oxyde de graphène (GO), sont réputés pour leurs propriétés mécaniques, thermiques et électriques exceptionnelles, ce qui les rend très prometteurs pour diverses applications avancées, telles que l'électronique flexible et la gestion thermique. Cependant, leurs propriétés intrinsèques, telles que les caractéristiques de faible dimension et la faible extensibilité, posent des défis qui peuvent entraver leur plein potentiel. Pour résoudre ces problèmes et exploiter pleinement leurs capacités, il est essentiel de développer des stratégies pour ajuster leurs caractéristiques inhérentes. Dans cette thèse, nous appliquons les principes …  Read more

Endocytic mechanisms are crucial for neuronal motility, function, survival, and polarity. During neurogenesis, the endocytic adaptor protein Numb acts as a cell-fate determinant in neural progenitors, where it segregates into only one daughter cell during asymmetric cell division. However, its role in post-mitotic neurons remains unclear. Like many other proteins involved in neural development, it is likely that Numb has different temporally regulated functions in progenitors and post-mitotic neurons. Here we investigate the role of Numb in the context of an in vivo system, specifically its possible involvement in neurite maintenance in adult neurons. In the mature retina, we report …  Read more

The genome constitution and phylogeny of hexaploid timothy (Phleum pratense L., 2n = 42) have been studied with C-banding and genome-specific DNA techniques. The cultivated species and two diploid wild relatives P. alpinum (2n = 14) and P. bertolonii (2n = 14) were karyotyped. In P. pratense, two sets of seven chromosomes could not be distinguished from each other either in gross morphology or in C-banding patterns and the third set was found to be differentiated from them. Two genomes, A and B, were established in this species presumably with the genome formula of AAAABB. The banded karyotype in P. …  Read more

Protein arginine methylation, catalyzed by protein arginine methyltransferases (PRMTs), is an important post-translational modification that diversely regulates biological processes. RGG/RG motifs, which include RGG and RG repeats interspersed with spacers of different amino acids, are preferred substrates of PRMTs. RGG/RG motifs containing proteins have been identified in a wide range of life forms (e.g., bacterial, fungi, plant, and animal) and viruses. A large portion of the RNA binding proteins (RBPs) harbor RGG/RG motifs. These proteins are involved in the key process of RNA metabolism and their dysregulation lead to developmental diseases, cancer, and increase susceptibility to viral infections. My thesis …  Read more

Omanovic, Sasha (Supervisor2)  Read more

This thesis contributes to covariance and volatility modeling in time series and econometrics, with applications to the estimation of autocorrelation matrices, portfolio optimization, and capital asset pricing models with stochastic volatility. We emphasize methods aimed at producing relatively parsimonious models, such as the simplification of covariance matrices through pretesting and numerical regularization with the Alternating Projection Algorithm (APA) [Dykstra(1983), Boyle & Dykstra (1986)], as well as extensions of the stochastic model in a CAPM-type model. The thesis is divided into three main essays. From a statistical viewpoint, the first essay studies correlation estimators regularized by the APA algorithm to avoid …  Read more

The ever increasing demand for greater bandwidth has fuelled the research and development of optical communication systems that can operate at higher and higher speeds. Therefore, wavelength tunable optical sources capable of generating short pulses at high repetition rates have garnered an increasing amount of interest. Actively mode-locked fibre lasers have been widely investigated and used to create such optical sources. The use of all-optical mode-locked lasers is particularly interesting because they are not limited by electronic bottlenecks and can potentially scale much better at higher data rates. This thesis presents an all-optical mode-locked semiconductor fibre laser (ML-SFL) incorporating a …  Read more

Aujourd'hui Kademlia est l'un des les plus utilisés DHTs (Distributed Hash Tableau) dans les réseaux P2P (peer-to-peer). Cet article étudie une question essentielle des réseaux "overlay" de Kademlia d'un point de vue mathématique: combien de temps faut-il pour localiser un noeud? Pour y répondre, nous introduisons un graphe aléatoire K pour modéliser un réseau de Kademlia et étudier la complexité d'un algorithme de routage de Kademlia.  Read more

Les arbres aléatoires sont omniprésents dans la science informatique. Un modèle particulièrement attractif est l'arbre choisi uniformément de manière aléatoire parmi une collection d'arbres. Beaucoup de ces modèles sont équivalentsà l'arbre de Galton-Watson conditionnelle sur sa taille — ces arbres, en retour, remontent au modèle proposé par Bienaymé, Watson and Galton pour l'évolution des populations. Cette thèse traite des questions sur les arbres aléatoires qui sont restées sans réponse jusqu'à présent. En particulier, nous étudions les conditions d'existence des familles de sous-arbres avec une forte probabilité dans un arbre de Galton-Watson de la taille n. Nous donnons d'abord une approximation …  Read more

Nous présentons une nouvelle méthode pour prétraiter un modèle réduit, en entraînant un réseau de neurones pour approcher le champ de distance signé du modèle réduit en utilisant une technique d'apprentissage actif. Le réseau de neurones entraîné est utilisé pour évaluer l'état d'auto-collision ainsi que la gestion de l'auto-collision pendant la simulation en temps réel. Notre approche d'apprentissage hors ligne consiste en deux étapes d'apprentissage. L'apprentissage de la première passe génère un nuage de points positif et négatif qui est utilisé dans l'apprentissage de la seconde passe pour apprendre le champ de distance signé du sous-espace réduit. Contrairement aux approches …  Read more

Les oscillations forcées (FO), provoquées par des perturbations périodiques externes, menacent le fonctionnement sûr et stable des réseaux électriques. Avec la pénétration croissante des ressources à base d’onduleurs (IBR), de nouveaux mécanismes de FO apparaissent, car les IBR interagissent avec le réseau par des boucles de contrôle plutôt que par l’inertie physique. Ces dynamiques créent des défis pour l’identification et la localisation des sources de FO, tandis que les méthodes existantes dépendent souvent de modèles système détaillés, d’un réglage important, ou échouent dans des conditions telles que la résonance et les modes faiblement amortis.Cette thèse développe une méthodologie entièrement fondée …  Read more

La synthèse des protéines (ou traduction des ARN messagers) est une étape clé de la régulation de l'expression des gènes dont la dérégulation est associée au développement de nombreuses pathologies humaines telles que le cancer. Le facteur d'initiation de la traduction eIF5A est activé par hypusination, une modification post-traductionnelle unique à eIF5A, qui est catalysée par deux enzymes : deoxyhypusine synthase (DHS) etdeoxyhypusine hydroxylase (DOHH). Bien que l'hypusination de l'eIF5A joue unrôle majeur dans la régulation de la traduction et semble être impliquée dans l'oncogénèse, les mécanismes moléculaires participant à son contrôle sont peuconnus. Nos travaux récents d'analyse à large …  Read more

Contrary to the view of many interpreters that Francis of Assisi (1181--1226) dabbled in church renovation for a few years following his first conversion experience in 1205, architecture remained a central preoccupation until his death in 1226. His creative practice ranged from hermitage planning to the clothing design of its occupants, from architectural legislation to the composition of psalms to be sung in the hermitage churches. Through the medieval art of memory, Francis formed his architectural intentions around two contemplative foci: first, the symbol of the tau, which became his attire, prayer position, signature, talisman for healing the sick and …  Read more

When continuous monitoring devices such as the electrolytic respirometer are used for performing biodegradation experiments, cumulative data are acquired. The structure of these observations limits the reliable application of existing methodologies for analyzing cumulative respirometric biodegradation trends, because the resulting error terms are likely to be highly autocorrelated. To overcome these limitations it is proposed that the Oxygen Uptake Rate (OUR) should be used as the data source for further analysis, because the dependence of the error terms is then removed. To model uniform reaction rate respirometric biodegradation OUR data trends, 1st and 2nd-order OUR models are proposed. Theoretical and …  Read more

Although the first dishwashing machine was patented in 1879 (45), it was quite some time before any interest was shown in the possibility of improperly cleansed eating utensils acting as vectors for the transmission of diseases. [...]  Read more

A shift has occurred in how mental health professionals, gay activists, and sociologists view the disclosure of homosexuality to others. While secrecy was once viewed as more desirable, disclosure is now seen as more advantageous. In this context, I look at how a sample of gay men manage information concerning their sexual preferences. I document their patterns of secrecy and disclosure and their rationales for being selectively open and secretive. I also show that gays face an interactional dilemma in the several types of relationships they have with nongays, regardless of whether they are open or secrective. I also examine …  Read more

Gallbladder disease has doubtless been present for as long as man and animals have existed, and known for as long as cadavers have been opened. There is on record a case of gallstones in an Egyptian mummy of the 2lst Dynasty. (British Museum). Since the first report of gallstones in the 14th Century, extensive studies have been carried out in an effort to determine the etiology of the condition. [...]  Read more

Specimens of Lake Shore Tuff and Porphyry, Nundydroog Amphibolite, Kerr Addison Green Carbonate Breccia, and McIntyre Carbonated Lava have been ruptured under compression, tension, torsion and direct shear. The results were graphically plotted according to Mohr's strength theory, and the constructed angles of failure compared with the experimental measured angles. According to Mohr, the strength of the rock is a function of sliding friction, but the graphical and experimental results indicate rather that sliding friction and interlocking govern rock failure. [...]  Read more

Marine biological collections were made at Tanquary Fjord during the summer of 1963 and 1964 under a contract between McGill University and the Defence Research Board of Canada. Exploratory collecting was done in 1963 by Mr. B. Frost and Mr. J. Haight, which included widespread sampling of plankton, temperatures, and salinities. During the summer of 1964 (May 8 - August 25) plankton collections and related measurements were taken by the author and an assistant. The 1964 program was designed to make all data easily comparable by sampling at standard depths, at equal time intervals, and as close to the same …  Read more

In order to increase the validity of numerical models of the detonation of heterogeneous titanium explosives, experimental results are needed. The combustino of titanium is studied using two experimental techniques. The first technique is the study of the burn time for a single particle over a wide range of initial diameters while altering the oxygen concentration. To accomplish this a new flat flame burner to study particle burn time has been designed. Luminous tracks caused by the light emitted by the combustion of the particles are analyzed and burn time is inferred. Burn time in air and in an oxygen …  Read more

Agricultural research in Canada is largely centralized on Experimental Farms and Stations and at Agricultural Schools and Colleges where the property is owned, considerable equipment is available and a highly technical staff is employed. It is not possible for government services or educational institutions to establish such units in each of the numerous localities where study is required. Various methods of solving this problem have been developed, Many methods are dependent on farmer interest for their success, in others a small allowance is made for crop loss and inconvenience caused by the presence of tests on the farm. Some local …  Read more

La technologie de reconnaissance faciale (RF) menace la vie privée et a fait preuve de partialité contre certains groupes démographiques, ce qui peut avoir de graves implications lorsque cette technologie est déployée par la police ou par d'autres agents gouvernementaux. Cette thèse explore les conditions qui devraient être remplies avant qu'un moratoire largement proposé sur la technologie de reconnaissance faciale puisse être levé en toute sécurité. Ces conditions comprennent la mise en place d'un système de vérification pour mesurer la précision et le biais des modèles RF, ainsi que la mise en œuvre d'un cadre de gouvernance pour la collecte …  Read more

Uveal melanoma has a high mortality rate, with approximately 45% of patients dying due to liver metastasis within 15 years of initial diagnosis and local treatment. As the eye lacks lymphatics, there is no staging of uveal melanoma according to lymph node metastasis. The search for new prognostic factors and therapeutic targets is therefore crucial to the advancement of uveal melanoma research. The expression of cyclooxygenase-2 (COX-2) has been investigated in human malignancies such as cutaneous melanoma. Immunohistochemical studies were therefore used to show that uveal melanomas do express COX-2 and that this expression is associated with various histopathological markers …  Read more