McGill University Thèses et mémoires par auteur commençant par B

A 915 MHz Doppler radar was able under certain conditions to provide Doppler spectra containing separate and distinct modes due to scattering by rain and by the clear air. The rain spectra are broadened and shifted on the velocity axis due to turbulent air motions. Information in the clear air mode is used to correct for these effects, leaving in the rain spectra the reflectivity-weighted distribution of drop fall speed, from which the drop-size distribution can be computed. The fast Fourier transform and two iterative methods of deconvolution were applied to simulated Doppler spectra. We concluded that the iterative methods …  Read more

S'approvisionner en nourriture est essentiel à la survie et au succès reproducteur. Même si plusieurs aspects des comportements d'approvisionnement sont innés, l'apprentissage influence souvent l'efficacité, les techniques et les choix alimentaires durant la recherche, la manipulation et l'ingestion des aliments. On peut donc s'attendre à ce qu'il soit avantageux de choisir et/ou de s'approvisionner avec un partenaire qui a appris à s'approvisionner efficacement et qui peut utiliser rapidement de nouvelles ressources. Cependant, peu d'études ont examiné si les comportements d'approvisionnement appris peuvent guider les décisions quant au choix de partenaire, et si les individus profitent du succès d'approvisionnement de leur …  Read more

La thèse se compose de trois chapitres qui étudient la géographie économique interne, les frictions spatiales et les multiples dimensions du comportement d'exportation des entreprises. Ils présentent une structure spatiale explicite au sein d'un pays exportateur et examinent comment les différences de caractéristiques géographiques affectent les marges extensives et intensives des activités commerciales des entreprises, ainsi que le comportement de fixation des prix. Le premier chapitre étudie l'apprentissage des entreprises auprès de pairs exportateurs dans différents réseaux spatiaux pour réduire l'incertitude de la demande d'un marché étranger, formalisant la relation entre les frictions spatiales dans l'apprentissage et la marge extensive …  Read more

A l'ère de la réconciliation au Canada, certaines personnes voient l'éducation comme un chemin à la réconciliation, tandis les autres la considère comme un outil du projet colonial-des-colons. Cette recherche analyse d'une façon critique Shared Learnings: Integrating BC Aboriginal Content K-10, une ressource créée par la branche d'Aboriginal Enhancement de la Ministère d'Éducation on Colombie-Britannique, pour inclure du matériel Autochtone dans les cours de maternelles jusqu'à 10e année. Les objectifs de cette recherche sont généralement d'enquêter sur le colonialisme des colons dans l'éducation et plus précisément de déterminer si une ressource créée pour bénéficier les étudiants Autochtones et pour inclure …  Read more

Shaw, A. (Supervisors)  Read more

Maass, O. (Supervisors)  Read more

In order to alleviate poverty in Mexico, the federal government created a form of land tenure called the ejido. People in the ejido work and live under a particular set of federal regulations which, among other things, severely restricts transferring ejido land. After almost a century of being legislated, however, the ejido has not helped its inhabitants rise out of poverty. Moreover, the ejido, I argue, became an impediment to even economic and political progress in Mexico because it isolated a portion of the population within this regime and placed barriers to the exercise of its members' constitutionally protected rights …  Read more

Mutations in the yeast gene KRE1 lead to resistance to the K1 killer toxin of S. cerevisiae. The resistant phenotype is associated with a 40% reduction of the cell wall (1 $ to$ 6)-$ beta$-glucan fraction. Yeast cell wall (1 $ to$ 6)-$ beta$-glucan is a highly branched glucose polymer composed predominantly of linear (1 $ to$ 6)-$ beta$- sc D-linked glucopyranosyl residues. This glucan acts as a receptor for the killer toxin, leading to a concentration of active toxin on the yeast cell surface. The KRE1 gene was cloned by complementation of the kre1-1 mutant allele. The KRE1 gene …  Read more

Two samples of high sulfur organic soils from the Province of Quebec were investigated as to the nature of their sulfur content.It was found that over 98 percent of the sulfur was organic in nature and that only a small amount of inorganic sulfur was present as very little was removed byelectrodialysis or by the solvent action of water or dilute acid. No attempt was made to isolate any organic sulfur-containingcompound as the purpose of this investigation was to determine if the sulfur bears any definite relation to phosphorus or nitrogen.Since no evidence could be obtained of the existence of …  Read more

Trust forms the foundation of patient-physician therapeutic relationships and is positively associated with care-seeking, collaboration and adherence in primary care. However, data on trust formation remains sparse in pediatric emergency and surgical care contexts, where brief, emotionally charged and high-risk circumstances require tailored measurement instruments.Traditional instrument validation is time- and resource-intensive, limiting the feasible development of appropriate tools. This prevents efforts to understand healthcare quality and identify improvements. Therefore, this thesis hypothesizes that large language models (LLMs) can improve feasibility of instrument validation by creating a synthetic instrument validation (SIV) framework that maintains rigorous psychometric principles. Evaluation of the SIV …  Read more

Yong, R. N. (Supervisor)  Read more

"Injury to the central nervous system as a result of cerebrovascular accidents (CVA) often leads to impairment in balance and mobility. Very little is known about the strategies that patients with CVA employ to prevent falls during unexpected changes of a support surface while patients are standing and walking. Previous studies showed that light touch increases postural stability in healthy subjects. However, it is not known whether patients with CVA would benefit from light touch in the same way as the healthy subjects do. Three studies in this research were conducted to examine the impact of stroke on postural responses …  Read more

Les études qui cherchent à prédire la microstructure cérébrale à l'aide d'images par résonance magnétique (IRM) nécessitent un alignement précis des coupes d'histologie cérébrale traitées aux données IRM 3D correspondantes, afin de les comparer avec les données d'histologie de vérité terrain. Cependant, réaliser un tel alignement est un problème exigeant, dû aux distorsions tissulaires et aux divers contrastes observés en IRM et dans les tissus analysés. Des études précédentes ont proposé de créer un modèle concave avec le contour du cerveau en question imprimé en 3D en se basant sur des données d'IRM, pour que le cerveau soit fixé dans …  Read more

Développement de méthodes basées sur l'IRM pour l'imagerie ex vivo à haute résolution et la reconstruction des volumes de tissus histologiques traités Evaluer et valider les méthodes d'imagerie non invasive ainsi que les mesures dérivées est essentiel pour comprendre l'organisation et le fonctionnement du cerveau normal et pathologique. L'IRM in vivo et ex vivo permet l’étude de la microstructure tissulaire et fait intervenir au préalable des étapes de fixation et coloration des tissus, puis de recalage des images de microscopie avec les images obtenues in vivo. Cependant, la qualité de la reconstruction de volumes en trois dimensions (3D) de tissus …  Read more

Gravity heat pipes (GHPs) are closed two-phase thermosyphons, which are also referred to as gravity-assisted wickless heat pipes. They are constructed by first evacuating a closed tube and then filling it with an appropriate amount of a chosen working fluid. The bottom portion of the tube is partially or fully filled with the liquid phase of the working fluid, and it is heated to perform as an evaporator. The upper portion of the tube is cooled and serves as a condenser. The central portion of the tube is usually very well insulated and referred to as an adiabatic section. A …  Read more

p53 is a tumor suppressor protein that is mutated in up to 50% of human cancers. It regulates the expression of hundreds of genes, which cause cell cycle arrest, cellular senescence, or apoptosis. We are hypothesizing that MYSM1, a chromatin interacting deubiquitinase, regulates the transcriptional activity of p53 by localizing to DNA with chromatin modifying factors, and controlling post-translational modifications of p53 or the chromatin at p53 target promoters. We recently demonstrated that loss of Mysm1 results in p53 activation in the mouse hematopoietic system, while inactivation of p53 can fully rescue the phenotypic abnormalities seen in Mysm1-knockouts. Mass spectrometry …  Read more

The coming into force of "free trade agreements" across the Western Hemisphere since the late 1980s has been a historic change that is still in the process of development. This essay seeks to explain this development. To do so, it investigates examples of the historical development of social relations in the hemisphere. The political will to carry out such a plan can be found in each country in the social base that sees benefit in the course. While this political will exists, everywhere the process has been a contested one, both domestically and internationally. This policy will continue to find …  Read more

One of the most important of the many difficult problems which the provincial representatives at the memorable Quebec Conference had to settle before the proposed Union of the British North Amerioan colonies could be successfully consummated was that of the financial arrangements. In contrast to the American constitutional convention of 1787, the conferences at Charlottetown and Quebec were held "in camera" with the unfortunate result that the meagre records and available evidence as to their deliberations are very fragmentary. The financial arrangements which the majority eventually decided upon were adopted in resolution form and these resolutions, issued by the Quebec …  Read more

The main theme of this study is income retention of Canadian manufacturing corporations. The data with which we have worked relate to forty-three well known companies and to the years 1932-1953 inclusive. Financial data of the kind we require are almost unobtainable for the 1920's and for this reason we have not been able to make a detailed study of income retention patterns before 1932.  Read more

It is the objective of this thesis to examine contacts between the British government and German opponents to Hitler during the "Phoney War" (September 1939-May 1940). Throughout this nine month period opponents to Nazism within Germany sought both material and moral support from the British government for an overthrow of the National Socialist regime. This work analyzes the channels through which communication between the German opposition and the British government were established and the nature of the discussions which took place. The work also examines the British reaction to the German overtures.  Read more

In establishing the range of an Historical Geography it is often wise, for the sake of clarity, to outline those things which are not within the scope of a particular work as well as its actual aim. It is not the aim of this thesis to present a complete historical geography of Brome Countyr nor is it intended to examine selected aspects of the history of the country, simply placing them in their geographical setting in order to show the influence of environment. Rather,its role is to reconstruct the economie landscape of the nineteenth and early twentieth centuries at meaningful …  Read more

The initial objeot of the research was to convert cellulose, a linear polymer, into branched-chain polymere of known constitution by condensing some of its free hydroxyl groups with acetobromoglucose, acetobromocellobiose, or acetobromocellodextrins. A comparison of the linear starting material and the branched products would then reveal the effect of known amounts of branchlng on solubility, fiber formation, vlscosity and other physical properties. Such information would be of great value in developlng an accurate knowledge of amylopectin, the branched-chain component of starches.[...]  Read more

The Montreal Repertory Theatre mounted a regular series of play productions every year from 1930 to 1961. They deliberately set out to follow the Little Theatre tradition of Antoine while profiting from later developments in England, Ireland and the United States. At a time when no alternatives existed in Montreal they provided theatre education at a high level and helped in the formation of many distinguished careers. This study examines the work of MRT in a historical context, and as revealed in the company's surviving documents and in contemporary reports. The written record is supplemented by interviews with persons who …  Read more

The hydrolysis of acetyl-dl-carnitylcholine, I-carnitylcholine and acetyl-dl-carnitine by the cholinester hydrolases was investigated. The ester bonds of acetyl-dl-carnitylcholine were hydrolyzed by the acetylcholinesterases (rat brain, human and bovine erythrocyte enzymes) to the extent of 25 per cent. The hydrolysis appeared to be stereospecific. Acetyl-dl-carnitylcholine was hydrolyzed slightly by purified human serum but not by fresh human plasma or purified horse serum cholinesterases. Several preparations of both acetylcholinesterase and cholinesterase failed to hydrolyze I-carnitylcholine and acetyl-dl-carnitine. These three compounds, as well as several other choline esters, competitively inhibited acetylcholinesterase hydrolysis of acetylthiocholine. Acetyl-dl-camitylcholine had marked affinity for acetylchol inesterase whereas acetyl-dl-carnitine …  Read more

The dietary and medicinal uses of indigenous green vegetables were studied quantitatively over a 13-month period in a rural, semi-rural and urban K'ekchi population in Guatemala. Seventeen species of indigenous greens were consumed, with seasonal variation in intake (p $<$.001) being related to agricultural practices. There was a lower frequency of consumption of greens among the urban group (p $<$.001). Within, and between, the communities, individuals exhibited heterogeneity in dietary intake and approaches to treatment of helminthic infection. There was no association between dietary intake of indigenous greens and the socioeconomic indicators measured (age, type of employment, household size and …  Read more

Amylose based chromatographic chiral stationary phases (CSPs) are widely used throughout liquid chromatography to separate enantiomers, although little is known about the interaction processes operating on these phases. This thesis describes a systematic study into the retention and enantioselective separation capabilities of the tris (3,5-dimethylphenylcarbmate), tris (R-phenylethylcarbamate) and tris (S-phenylethylcarbamate) stationary phases. The underlying aim of this work was to obtain an understanding of the solute-stationary phase interactions which are responsible for the chromatographic retention and separation of enantiomers. By development of quantitative structure-enantioselective retention relationships (QSERR), it was possible to identify the primary components involved in the molecular interaction …  Read more

The study of chromosome structure and behaviour antedates by several decades the establishment of genetics on a scientific basis. Beginning, inevitably, as a purely descriptive discipline, chromosome cytology has in recent years expanded and branched until it promises to play an important part in the integration of many fields of scientific investigation. Already it has invaded such subjects as molecular physics and protein chemistry, and made a start, however small, in the interpretation of genetical and embryological observations in chemical terms. With the improvement of present methods of investigation, and the development of new tecnniques, we may look hopefully for …  Read more

In the course of the cytological studies of cereals conducted in this department it was noticed, in a number of cells, that two or more bivalents were interlocked with each other at meiotic metaphase. The percentage of cells containing such interlocked bivalents is unusually high in the speltoid mutants of wheat (Triticum vulgare Host), unbalanced types having 40 or 42 chromosomes with a homozygous deficiency instead of the usual 42, and resembling Triticum Spelta more than T. vulgare. [...]  Read more

A genetic epidemiological approach was used to study inherited susceptibility as a risk factor for tuberculous disease following infection with Mycobacterium tuberculosis. Based on an experimental mouse model, the hypothesis was that a human recessive susceptibility gene is located on the long arm of chromosome 2 and has a major effect on the development of disease. Clinical and genetic data from family members were used in linkage analyses with the lod score method to test for co-segregation of genetic markers and the susceptibility trait. Evidence for linkage to the candidate chromosome region was obtained for a large, multiplex Aboriginal Canadian …  Read more

Boivin, Jean-Francois (Supervisor1)  Read more

During recent years tbe increasing economic importance of the mosaic and other virus diseases of our crop plants has given a great impetus to the study of these obscure troubles. As a result, the known mosaics have been increased £rom the single one affecting tobacco to numerous mosaics of other Solanaceae, Leguminoseae and Gramineae, with scattered cases in twenty or more additional families of both Monoctotyledons end Dicotyledons. Current literature is replete with reports of mosaic diseases on new plants, either wild or cultivated, and studies concerning plant virus diseases are daily entering widely divergent channels of research. [...]  Read more

Le cancer de la peau est la forme de cancer la plus répandue dans le monde. Un rapport de Skin Cancer Foundation estime qu'un Américain sur cinq développera un cancer de la peau avant l'âge de 70 ans. Le mélanome, qui est considéré comme le type de cancer de la peau le plus mortel, est à l'origine de la majorité des décès. L'autre type, le non-mélanome, qui se subdivise en carcinome basocellulaire (BCC) et en carcinome spinocellulaire (SCC), affecte des millions de vies humaines chaque année.Le diagnostic précoce de tous les cancers de la peau, y compris le mélanome, permet …  Read more

La lutte contre le changement climatique nécessite de nombreuses ressources minérales. C'est pourquoi d'énormes projets d'exploration et d'exploitation minière ont vu le jour dans de vastes régions du monde. Ces projets se sont considérablement accélérés dans le cercle arctique, en Afrique, en Asie du Sud-Est et en Amérique du Sud. Entre-temps, de nombreuses initiatives volontaires de normes d'exploitation minière durable/responsable ont vu le jour (par exemple, the Initiative for Responsible Mining Assurance, the Extractive Industries Transparency Initiative, the Global Reporting Initiative Standards, the Towards the Sustainable Mining, and the Sustainability Accounting Standards Board). Ces normes délivrent des certificats aux sociétés …  Read more

La destruction osseuse par des cellules multinucléées spécialisées ou ostéoclastes est importante pour les processus physiologiques du développement des os et de la naissance des dents. Les ostéoclastes sont aussi impliqués dans plusieurs maladies telles que l'ostéoporose, la polyarthrite rhumatoïde et la parodontite. L'ostéogenèse imparfaite (OI) est la forme la plus commune de fragilités osseuses héréditaires et elle est normalement causée par des mutations dominantes dans les gènes codeurs pour les chaines alphas du collagène de type I, COL1A1 ou COL1A2. Bien que les ostéoclastes n'expriment et ne produisent pas de collagène, de l'ostéoclastogenèse stimulée et de la destruction osseuse …  Read more

Friscic, Tomislav (Supervisor2)  Read more

In this thesis we investigate gapped and gapless topological states, their connection to entanglement and their response to perturbations such as disorder and external magnetic fields. We start out by analyzing numerically and analytically the entanglement entropy of a spin-orbit coupled topological superconductor and its signature of the topological phase transition. We find that the entanglement entropy obeys the area law and that it displays a second order phase transition at the phase transition point. Subsequently, we investigate the effect of a random disorder potential on the topology of the system by using a real space Chern number and comparing …  Read more

Distortion of radar echo patterns by rain attenuation can be corrected by measuring the area under the rain intensity-range curves in successive steps and correcting the succeeding steps in accordance with the attenuation indicated by the preceding ones. Great accuracy in the initial calibration of the radar is necessary to avoid increase of error in the corrected rain intensities with depth into the rain shower. A radar calibration error of plus or minus 15% in rain intensity, or approximately 1 db in power level, is amplified by attenuation corrections, until at a depth into the shower equivalent to 100 mm …  Read more

The ribosome recruitment phase of translation initiation is the rate-limiting step of protein synthesis and involves binding of the 40S ribosomal subunit and associated factors to the 5'end of mRNAs. Ribosome recruitment to mRNA templates is catalyzed by the eIF4 class of initiation factors comprising eIF4F, a multisubunit complex that binds to the 5'end of mRNAs and prepares transcripts to receive ribosomes, as well as eIF4B and eIF4H, which help eIF4F in its task. mRNA preparation by eIF4F is thought to be accomplished by the eIF4A subunit of the eIF4F complex, an RNA helicase believed to unwind secondary structure close …  Read more

Tremblay, Marie-Éve (Supervisor1)  Read more

The main work of this paper is the description of electronic equipment that has been developed to measure the parameters of junction transistors over an appreciable frequency range and with changing bias points.  Read more