McGill University Thèses et mémoires par auteur commençant par J

Mysak, Lawrence A. (Supervisor2)  Read more

The study of the polymerization and association of simple organic substances, and the nature of the super molecular state is the subject of intensive investigation at the present time, and is a problem, which as yet remains unsolved. Many important isolated facts have been discovered and a variety of (1) theories proposed, but, as Haworth points out withregard to polysaccharides, but which may be applied to polymerization and the supermolecular state in general, " - no finality is to be expected in the present state of knowledge. The time is probably not distant when greater harmony of opinion will prevail …  Read more

Latham, G. (Supervisors)  Read more

Au cours des trois dernières décennies, l'espace a été redéfini. Les acteurs privés ont investi dans les activités spatiales, en se concentrant sur les méga-constellations prévues comme OneWeb et Starlink. Ces lancements privés ont non seulement significativement augmenté le nombre d'objets en orbite, mais ont également renouvelé la discussion sur le rôle des acteurs privés. Cette thèse se concentrera sur les régulations des acteurs privés pour la mitigation de la création de débris spatiaux. La thèse examinera la justification légale pour les États d’autoriser les licences des acteurs privés, ainsi que les activités nécessitant une licence. Cependant, l'objet premier de …  Read more

Le système cardiovasculaire est le premier système à se développer dans l'embryon. Au début du développement, les angioblastes se différencient en cellules endothéliales et s'assemblent pour former un réseau de vaisseaux sanguins, selon un processus complexe appelé vasculogénèse. Ce réseau, appelé plexus capillaire primaire, se remodèle lorsque le cœur commence à battre et que la circulation des érythroblastes commence. Ce remodelage permet la formation d'une structure vasculaire hiérarchisée, avec le recrutement de cellules musculaires lisses au niveau des grands vaisseaux ainsi que celui des péricytes au niveau des petits vaisseaux.Le processus de remodelage permet la formation d'artères et de veines …  Read more

The concept of angiogenesis, the formation of new blood vessels from preexisting vessels, is simple and well defined but the execution of this concept is highly complex, involving factors that are poorly understood. What we certainly know, is that angiogenesis is a vital component of life and death; life with respect to the development of the cardiovascular system in the early embryos, and death when angiogenesis occurs in an uncontrollable manner such as during tumor development. Mechanotransduction is the translation of mechanical forces into a signaling cascade that leads to the activation of genes. The vascular endothelial growth factor (VEGF) …  Read more

Electric power substations are very vulnerable to earthquakes. This study has analyzed the seismic risk index of electric power substations of Hydro-Quebec. The critical parameters responsible for vulnerability of substations are identified by statistical analysis of field data. Correlation of different parameters with vulnerability, sensitivity of the weighting factors of critical parameters and sensitivity of seismic exposure levels to seismic risk index are also studied by statistical analysis. Study shows that year of manufacture of equipment, anchoring of heavy equipment, load-bearing system of the building, and control systems are the four most critical parameters for vulnerability. Vulnerability of substations largely …  Read more

This thesis examines the role of Christian idioms and practices in the self-fashioning of second generation Haitians of Protestant faith in Montreal. These members of Baptist and Pentecostal Haitian Churches encounter the particular challenges of combining multiple affiliations as they face racism and pressures to assimilate to the mainstream Quebecois society. Taking this context into account, I examine how young Protestants use and subvert religious symbols and practices in constructing their identity, and how they negotiate their position in their world defending themselves against denigrating stereotypes. My research explores how they undertake their personal as well as collective salvation through …  Read more

Coulson, J. (Supervisor)  Read more

In this thesis, reconfiguration schemes for multipipeline structures and rectangular arrays are analyzed for their yield and area utilization, and a new reconfiguration scheme is proposed for these structures. Schemes for rectangular arrays are classified on the basis of locality of spares within the array. A methodology is developed to analyze the yield and area utilization of reconfiguration schemes in each class. Analytical solutions are obtained for yield and area utilization of representative schemes from each class, and schemes are compared for their optimal area utilization. The effect of the size of interconnect area on yield and area utilization is …  Read more

Increasing water and nitrogen use efficiency is essential to increase crop production and to reduce environmental degradation. Cellulosic hydrogels derived from paper waste, have the ability to retain and gradually release water and nitrogen for optimum plant growth. This study assessed crop response to water and NO3 − N with hydrogels amended in the soil. Tomato was used as the crop for this study as it is the most widely cultivated vegetable crop with a sensitive response to water and nitrogen. An experiment was conducted during 2020-2021 in the research greenhouse at Macdonald Campus of McGill University, comprising the following …  Read more

Pour la majeure partie de la littérature existante en apprentissage par renforcement, lorsqu'il est question de la distribution du récompense, on étudie l'espérance du récompense plutôt que l'entièreté de la distribution. Dans les applications critiques pour la sécurité, un tel calcul simpliste utilisant le récompense attendu pourrait ne pas être suffisant. Pour les applications de type système critique telles qu'en finance ou en supervision de processus industriels, il est impératif que la performance des agents soit fiable et constante. Typiquement, la variance observée du récompense est attribuée au caractère stochastique de l'environnement et de la convergence des agents. Nous proposons …  Read more

Cette thèse explore des méthodes visant à améliorer la fiabilité des algorithmes d’apprentissage par renforcement (RL) afin de faciliter leur déploiement pratique. Nos contributions portent sur trois défis majeurs : la variabilité des performances, la sensibilité au choix des hyperparamètres, et le besoin important de données pour une évaluation rigoureuse.Premièrement, pour atténuer la variabilité des performances, nous proposons des méthodes acteur-critique à moyenne-variance scalables qui optimisent conjointement le retour espéré et sa variance, améliorant ainsi la cohérence des politiques dans des environnements stochastiques. Deuxièmement, nous développons un cadre robuste d’optimisation de politiques pour les processus de décision de Markov contraints …  Read more

Tanny, Jason (Supervisor1)  Read more

Les actions abstraites temporellement ne représentent pas seulement des connaissances en configuration hiérarchique dans l’apprentissage par renforcement, ils améliorent également l’exploration tout en réduisant la complexité pour choisir les actions. Les options fournissent un cadre concret pour mettre en œuvre et de raisonner quant aux actions temporellement abstraites. Cette thèse tente de tester l’utilité des traces d’éligibilité avec des options et de trouver de bonnes façons de faire des mises à jour intra-options multi-étapes. Trois algorithmes, basés sur des méthodes hors-politique - échantillonnage préférentiel, tree backup et retrace(λ), sont proposés pour utiliser les traces d’éligibilité avec les options.  Read more

Maxime Bouchard (Internal/Cosupervisor2)  Read more

The cholesterol-lowering effect of corn fiber oil, obtained from the seed coats of corn kernels, has been reported previously. Corn fiber oil contains phytosteryl fatty acyl esters, ferulate phytostanyl esters, and free phytosterols. To date, however, no studies have examined the cholesterol-lowering efficacy of ferulate phytostanyl esters. Moreover, although plant stanols and sterols have been established as cholesterol-lowering agents over the past five decades, their exact mechanisms of action are not clearly understood. One of the possible mechanism is that plant sterols/stanols disrupts the normal sub-cellular cholesterol absorption by down-regulation of the influx sterol transporters such as the Niemann pick …  Read more

The fields of Nanomedicine is rapidly expanding. Already numerous nanoparticles have entered clinical trials. However, certain nanostructures, though, therapeutically and diagnostically promising, can induce toxicity both in vitro and in vivo; cadmium telluride quantum dots fall into this category. Quantum dots (QDs) are highly fluorescent, semi-conducting nanocrystals, that consist of a metallic core. Compared to traditional fluorophores, QDs have superior optical qualities, including resistance to photobleaching, broad spectrum excitation and narrow emission. Cadmium telluride (CdTe) QDs were the first to be synthesized without organic solvents, and thus, considered suitable for biological application. However, early studies demonstrated that QDs induced cytotoxicity …  Read more

In current pulping methods most of the lignin is probably dissolved at the expense of rendering the remainder less soluble owing to chemical condensation between particularly reactive sites in the lignin molecule. To gain more information about this undesirable reaction, the thesis by E. Eisenbraun had the object of discovering whether such reactive sites could be “blocked” by preferential condensation of the phenol-formaldehyde type. It was shown by three independant methods that 100g of spruce periodate lignin condensed with about 30 g of formaldehyde to form Ross-Potter, or formaldehyde, lignin.  Read more

Cette thèse décrit l’usage d’une ressource protéomique afin de définir l’organisation spatiale du réticulum endoplasmique (RE) et de prévoir la fonction de protéines peu charactérisées à ce jour. Par la protéomique, des protéines résidentes impliquées dans la translocation et la traduction (eIFs, Sec61, TRAP, et le complexe OST) sont enrichies dans le RE granuleux. Des chaperones résidentes et des enzymes de pliage (PDIs, calnexin et BiP) sont d’abondance égale dans le RE granuleux et le RE lisse. Le système de dégradation associé au RE (ERAD) (derlin-1, VCP/p97, sel-1L, enzymes de conjugaison de l’ubiquitin, protéasome) ainsi que les chaperones cytosoliques (Hsp90, …  Read more

Fast Radio Bursts (FRB) sont des phénomènes transitoires d'une durée de quelques microsecondes à quelques millisecondes qui prennent naissance à des distances cosmologiques. Certaines sources, appelées répéteurs, ont été observées comme émettant plusieurs sursauts.Le Canadian Hydrogen Intensity Mapping Experiment/Fast Radio Bursts (CHIME/FRB), située à Penticton, en British Columbia, est la seule à pouvoir détecter les FRB en raison de sa large gamme de fréquences (400-800 MHz), de son grand champ de vision instantané (~200 degrés carrés) et de son balayage quotidien de l'ensemble du ciel nordique. Il a détecté plus de 4,500 sursauts du début à la fin, présentés dans …  Read more

Hypomyelinating leukodystrophies are a group of rare, inherited white matter disorders characterized by abnormal myelin deposition during development.1,2 RNA polymerase III-related hypomyelinating leukodystrophy (POLR3-HLD) is caused by biallelic pathogenic variants in genes encoding the RNA polymerase III (Pol III) subunits.3–7 Pol III is responsible for the transcription of small non-coding RNAs with important roles in gene expression and protein synthesis.8 POLR3-HLD has a wide phenotypic spectrum and the underlying pathophysiology of how biallelic pathogenic variants in the genes encoding Pol III subunits leads to the phenotypes seen has yet to be elucidated.9 Due to the small sample size inherently present …  Read more

Cette thèse examine de manière critique l’efficacité de la gouvernance d’entreprise canadienne dans la promotion des intérêts des parties prenantes, en particulier en matière de lutte contre les changements climatiques. Au Canada, on observe une évolution vers une attente selon laquelle les administrateurs doivent prendre en compte non seulement la recherche du profit, mais aussi les intérêts des employés, des communautés et de l’environnement. Cette thèse soutient que le cadre du droit canadien des sociétés est structurellement inadéquat pour permettre une telle transformation. Le déséquilibre entre l’autorité accordée aux administrateurs et les mécanismes de reddition de comptes en place rend …  Read more

Ooi, Boon-Teck (Supervisor)  Read more

Although cardiac hypertrophy is a compensatory mechanism of the stressed heart, it ultimately leads to cardiac dysfunction. GATA-4, a member of the GATA family, plays an essential role in this process, nevertheless, its mechanism of action is still largely unknown. We have isolated a new evolutionarily conserved protein, ENDO1, that belongs to a new subfamily of PHD finger proteins. In adult mouse, ENDO1 was highly expressed in the kidney, lung, spleen, heart and brain. In ventricular cardiomyocytes, endogenous ENDO1 was expressed in the nucleus and cytoplasm. Overexpression analysis of antisense and sense GATA-4 suggests that GATA-4 downregulates endogenous ENDO1 in …  Read more

Termination of transcription just upstream of the late promoter on polyomavirus was studied. A mutant virus had previously been constructed. Results did not reveal any termination of transcription just upstream of the late promoter in the mutant A3-ins 5 when compared to the wild type A3 strain of polyomavirus. The effect of time of in vitro elongation on results is shown. RNA polymerases may traverse the entire genome and terminate shortly downstream of the late promoter, or termination in the region upstream of the late promoter is being masked. Alternatively, certain second termination signal(s) could be missing on the A3-ins …  Read more

A representation of degree n of a group is a homomorphism of the group into a group of nxn matrices with coefficients in a given field K. The image group of matrices is necessarily a sub-group of GLn(K), the group of all non-singular nxn matrices with coefficients in K. Two representations t and t, necessarily of the same degree n, are equivalent if there is a matrix T € GLn (K) such that T t(g)T-1 for every g € G. Equivalent representations are to be regarded as essentially the same.  Read more

Research practices of econometricians evolve rapidly. They have changed as much in the last two decades as they did in the preceding two decades when the primacy of the simultaneous-equation model was established. Much of what econometricians do now does not fit into the framework indicated by a preoccupation with statistical inference. Given this background, it is convenient to distinguish soft econometrics from its hard counterpart, which stresses mathematical statistics. This distinction is derived from a parallel in Cox's discussion of the behaviour of statisticians, and of the nature of data. To clarify the substance of soft econometrics and to …  Read more

Introduction: Dans le contexte actuel de la crise des opioïdes, les patients ayant subi une chirurgie bariatrique courent un risque accru de subir des préjudices liés à la prescription excessive d'opioïdes en période postopératoire. Cette étude visait à évaluer dans quelle mesure les opioïdes prescrits à la sortie de l'hôpital après une chirurgie bariatrique sont consommés par les patients.Méthodes: Cette étude de cohorte prospective multicentrique a inclus des patients adultes (≥18yo) subissant une chirurgie bariatrique laparoscopique. Les évaluations préopératoires incluaient des données démographiques et des mesures rapportées par les patients. Les informations concernant les interventions chirurgicales et les soins périopératoires …  Read more

Mukhopadhyay, Kakali (Internal/Cosupervisor2)  Read more

Piat, Myra (Supervisor)  Read more

The purpose of this dissertation is to propose a conceptual framework that can guide assessing and reporting on sustainability. The framework is rooted in a particular value set, is consistent with systems theory, and serves to focus indicator choice. Its development is influenced by a literature review that includes 220 state of- environment reports, several key aspects of economic thought, and thirtytheoretical models that address the human-ecosystem relationship. Four strategic elements that serve as areas of diagnosis or indicator domains are identified including (I) ECOSYSTEM; (11) INTERACI'ION; (Ill) PEOPLE; and (IV) SYNTHESIS. Each domain is linked to a set of …  Read more

Precup, Doina (Supervisor1)  Read more

This thesis studies the formation of the basic ideology of the Muh&dotbelow;ammadiyah during the period 1912--1942, analyzing in particular the fundamental aspects of its religious and social beliefs. The words and deeds of its leaders were crucial during the period in forming the Muh&dotbelow;ammadiyah's ideology, for these alone provided the basis for the movement's program. Their religious outlook reflected the movement's philosophical view of this world and the role of reason in understanding religion. This view was marked by openness, tolerance, and pluralism in dealing with other ideas, and a belief in the salutary character of change. What set the …  Read more

This thesis deals with the socio-religious role of the Muhammadiyah movement from 1912 to 1990. The study analyzes the fundamental ideology of the movement, and its implementation in the religious and social life of the Indonesians. Its religious outlook illustrates its character as a purifying movement which is devoted to performing religious practice ('ibadah) based on the authentic sources. At the same time it also provides ideas which enable the movement to encourage moral reform and yet which are adaptable to contemporary conditions. The ideas manifest themselves in the form of various religious activities of dakwah (propagation), and a great …  Read more

Estimates of genetic and phenotypic parameters of lifetime performance traits and estimates of correlations between these and first lactation traits were obtained using multitrait mixed model and Restricted Maximum Likelihood (REML) methodologies, and accounting for all known additive genetic relationships amongst animals in sires pedigree. Part-lifetime performance traits, i.e. two-, three, and four-parity totals of yield and profit, were also included in the analysis. Data were on 82,835 Holstein cows, daughters of 703 sires, calving first between September 1979 and December 1984 in the herds enrolled in Quebec Dairy Herd Analysis Service (QDHAS). Lifetime performance records, however, continued through December …  Read more

Cette thèse présente un estimateur de paramètres et d’état basé sur des noyaux, construitsur diverses implémentations d’estimateurs de type Recursive Least Squares. Le projet areprésenté un système utilisant des noyaux dans des espaces de Hilbert à noyaux reproducteurs (RKHS) et la propagation de co-variance. Ensuite, un problème d’estimation deparamètre est résolu en utilisant la régression multiple stochastique et les moindres carrésgénéralisés avec une pondération de co-variance appliquée pour résoudre le bruit élevé. Deplus, des intégrales multiples du noyau pour la réjection du bruit et pour la régressionmultiple d’un système non linéaire d’ordre élevé sont développées. Cette méthode récursiveest ensuite étendue …  Read more

Access to, and use of the geostationary orbit--a limited natural resource--is governed by the legal norms of international space law and international telecommunication law. In order to better understand the issues involved in its regulation, the fundamental elements of the geostationary orbit, its definition, technical characteristics, advantages and nature as a limited natural resource are examined (Chapter I). The legal regime governing an area or environment is built primarily upon its legal status; hence, in Chapter II, the legal status of the orbit is discussed. An analysis of the applicable legal principles of international space law follows (Chapter III); while …  Read more

It was first shown by Pauli 1) that from the requirement of Lorentz invariance, microcausality and positive energy and of the assumption that either commutators or anticommutators are c-numbers we must quantize, for the case of free field, half-integer spin field with Fermi-Dirac statistics and integral spin field with Bose-Einstein statistics. [...]  Read more

Latent inhibition (LI) is the attenuation in the acquisition of Pavlovian conditioning to a conditioned stimulus (CS) due to prior extensive exposure to that CS. It is assumed that LI is an animal model of attention in that animals learn to ignore the preexposed CS. The present series of experiments investigated the effects of selective serotonergic (5-HT) ligands known to increase 5-HT neurotransmission on LI using a conditioned emotional response (CER) procedure. In experiment 1, rats preexposed (PE) to 40 presentations of a tone CS acquired CER suppression more slowly than vehicle-treated nonpreexposed (NPE) animals, suggesting LI was obtained. Administration …  Read more

International air travel is the chosen means of transportation for hundreds of millions of people around the globe. At the same time, international civil aviation has witnessed a systemic threat from terrorists, who consider aircraft and other aeronautical facilities as surrogate targets. Among others, innocent travellers and passengers dissociated entirely from terrorists' personal or political ambitions are the victims. The Warsaw Convention, and subsequent modifications thereto, devised to regulate the civil liability of the air carrier vis a vis its passengers, falls short of recognizing this particular class of victims and may not be seen as an efficient legal instrument …  Read more

Bilingualism has been investigated by linguists interested in the phonemic and grammatical interactions of two or more languages used in the same community. The psychologist's interest centers on the effects of two sets of semantemes upon verbal behavior and thinking. Weinreich (1953) in a recent review of the literature reports several studies in which two types of bilingual systems are identified.  Read more

At the 1916 meeting of the American Psychological Association in New York City, Raymond Dodge delivered the presidential address entitled "The Laws of Relative Fatigue." His words set the tone for the historical background of this thesis. For students of the present generation, Dodge's statement may seem very puzzling. What is this all-important and pervasive phenomenon which he does not even feel needs a definition? "The concept of mental fatigue is so familiar that a precise analysis of its differentia has seldom seemed necessary" (p. 93).  Read more

In the comparatively new field of prestressed concrete design, many problems still await investigation. Web stresses in I-shaped prestressed concrete beams are of some importance in stirrup design, but little is known about their actual magnitude and direction. [...]  Read more