McGill University Thèses et mémoires par auteur commençant par B

A description is given of an automatic stereoscopic camera de-signed for cloud chamber photography. The design of other auxiliary apparatus for a cloud chamber is also presented. The details are given of a. method of hard gamma-ray determination involving the measurement of the ranges of photoprotons produced by the gamma radiation in a deuterium filled cloud chamber. [...]  Lire la suite

Recent revisions to Articles 9 and 1 of the Uniform Commercial Code (the "UCC") have proposed new intangible secured financing choice of law rules. These choices of law rules contain rules that represent all three major schools of thought in the field of conflicts of laws: multilateralism, substantivism and unilateralism. This thesis examines the new rules by analysing them in the context of the strengths and weakness of these schools of thought and in light of the requirements of a secured financing system. On the whole the strong mulitlateralist focus of the majority of the rules provides a solid basis …  Lire la suite

Objective. To estimate the distributions of thermal and vibration sensory thresholds in a healthy population taking into account important covariates. Methods. Sensory thresholds were measured using quantitative sensory testing for 148 volunteers free of neuropathic disease. Independent effects of age, gender, height, and skin temperature were estimated using multiple linear regression. Parametric and nonparametric methods were used to estimate the distributions of interest. Results. Significant age-related increases were observed for vibration thresholds (p $<$ 0.0001) and in the foot for thermal thresholds (p $<$ 0.0002). Height was significantly associated with vibration thresholds in the foot (p $<$ 0.003). Selected percentiles …  Lire la suite

Comme la plupart des étudiants américains j'ai fait la connaissance de Maupassant pendant mon cours de français. Malgré le caractère des cours de français aux Etats-Unis où on ne lit que des nouvelles prescrites, c'est à dire celles qui sont inoffensives aux jeunes Americains, j'ai beaucoup admiré le style et la foree de l'ecrivain. Cependant ce n'est que quand j'ai vraiment examiné cet homme par ses oeuvres, et par ce qu'il a dit de lui-même, et par ce qu'on a dit de lui, que je me suis rendu compte de son génie. Sans aucun doute, Maupassant a une place distinguée …  Lire la suite

Background. Benzodiazepines are sedative-hypnotic medications frequently prescribed in elderly patients for several clinical indications. An association with increased risk for falls has been reported but there is continued debate regarding which specific benzodiazepines are associated with this risk. Objectives. To estimate the risk of injuries from falls associated with benzodiazepine use in an elderly cohort taking into account patient characteristics and changes in patterns of use over time. Methods. Using information from provincial administrative health databases, 462,543 community-dwelling, 66 year old Quebec residents were screened for benzodiazepine use in 1989. Subjects who did not use benzodiazepines in 1989 were observed …  Lire la suite

The dissertation develops a theory-based, state-centered revisionist explanation of the development of Canadian broadcasting policy during the years 1955 to 1968. The hypothesis contends that state officials seek their own preferred policy outcomes rather than reflecting the preferences of societal actors. The concept of decision points is used to explore the origins of the 1958 Broadcasting Act and the 1968 Broadcasting Act. The evidence suggests the content of these measures was largely determined by bureaucratic actors. Two aspects of the 1968 legislation (the power to approve broadcasting licenses and extension of broadcasting regulatory jurisdiction to cable television) are examined in …  Lire la suite

The following thesis deals with the distribution of air traffic rights. Particular reference is made to the situation in the European Union and the changes that might occur in the aftermath of the "open-skies" decision of the European Court of Justice in November 2002. One major part of the thesis generally analyses different means of distributing limited public right, in order to determine an appropriate method for the allocation of air traffic rights. After a comparison with the telecommunication sector, it is concluded that the most appropriate approach is to conduct a Beauty Contest in the form of a Documentary …  Lire la suite

This report is a compilation of test results and analyses obtained on an oil impregnated paper power cable during the time period extending from early in 1959 to spring of 1961. The research was initiated and carried out in Northern Electric's Cable Engineering Laboratories with the intent to answer some practical questions on the dependence of the dissipation factor upon the dielectric and corona losses within the insulating systems of cables. [...]  Lire la suite

A technique is devised for corona-pulse intensity calibration of the corona detection circuit employed in the experiments; this calibration scheme may be regarded as a modification of one of the three suggested ASTM calibration methods. The remaining two methods are found to have serious inherent disadvantages and are discarded oh those accounts. A method, developed for the measurement of the corona discharge rate, is extensively used to analyze the sequence of discharge behaviour within spark gaps of various spacings and under different vapour pressures. The discharge rate measurements, in conjunction with toe observations on the voltage waveforms across discharging gaps, …  Lire la suite

Depuis 1940, la réputation littéraire de Paul Morand a subi une sérieuse éclipse. La politique en est en partie responsable, mais l'évolution des valeurs intellectuelles y est aussi pour beaucoup. Morand s'était identifié à une époque, celle de la génération de 1930. Elle lui avait reconnu un grand talent et l'avait placé presque au même niveau littéraire que Marcel Proust et André Gide. Nos aînés semblent avoir commis une monumentale erreur d'appréciation. Ils ont pris du strass pour du diamant, et se sont laissés éblouir par le "modernisme" de Morand. Cosmopolitisme, ésotérisme, snobisme, joints à une authentique élégance d'attitude, à …  Lire la suite

The rotations of rigid rods and fused doublets of equal-sized spheres in a shear field are in excellent agreement with Jeffery's theory for ellipsoids when the equivalent axis ratio Re is used. For fused doublets Re = 2. The mechanism of collision between equal-sized rigid spheres differs in several respects from that found in earlier observations. The collisions are not sharply defined and the disturbance occurs well in advance of particle contact. [...]  Lire la suite

Bien qu'il soit contraire à l'usage d'écrire une thèse sur un auteur vivant, l'œuvre de Monsieur Henri Queffélec a déjà reçu un tel accueil depuis quelques années, en France comme à l'étranger, que l'on peut bien entreprendre cette tâche sans qui elle coure le risque de paraitre prématurée. L'œuvre de Monsieur Queffélec est aujourd'hui assez riche et importante pour justifier une étude littéraire. Elle a d’ailleurs été traduite en plusieurs langues. Il y a quelques années, Queffélec était lu avec plaisir et intérêt, mais maintenant il prend sa place parmi les grands auteurs contemporains.  Lire la suite

Human FOXP3+ regulatory T (Treg) cells play an essential role in the maintenance of immune homeostasis by controlling self-tolerance while maintaining immune responses to non-self antigens. Treg cells constitutively express the master regulator transcription factor FOXP3, are hyporesponsive to in vitro TCR-induced proliferation, express low levels of inflammatory cytokines and inhibit the activation, maturation and effector functions of a variety of innate and adoptive immune cells. Mutation of the foxp3 locus and consequential abrogation of Treg cell function lead to the development of multi-organ autoimmunity in mice and in humans. Some have reported that Treg cell numbers and function are …  Lire la suite

Early life adversity (ELA) has been shown to be associated with emergences of psycho- andother pathologies later in life. These physiological and psychological effects are hypothesizedto be mediated by changes in stress physiology, namely the hypothalamic-pituitary-adrenal(HPA) axis, and the autonomic nervous system (ANS). Numerous studies have shown effectsof ELA on HPA-axis response. However, findings have been mixed with some researchersreporting potentiating effects of ELA on HPA-reactivity, while others have found bluntingeffects of ELA. Importantly, the majority of studies so far have focused on HPA-reactivity,neglecting to incorporate measures of the independent branches of the ANS. This thesis hypothesizedthat inter-individual differences in …  Lire la suite

Field studies of a population of Arisaema triphyllum affected by the systemic rust Uromyces ari-triphylli were conducted to examine dynamics of disease transmission and to identify factors influencing plant susceptibility to rust infection. Of undiseased plants that developed foliar infections during the growing season, 55% possessed active resistance to the rust disease, and were able to prevent the foliar infection from becoming a systemic one. Flowering increased the susceptibility of plants to both Mar and systemic infections. A phenotypic selection study was carried out to estimate selection on five plant traits and to determine the role of foliar infections of …  Lire la suite

The positron lifetimes in the alkali chlorides and sodium halides have been measured. Two lifetimes have been found in each of these materials, with a small fraction (of the order of a few per cent) of the positrons annihilating with the longer lifetime. The lifetimes vary from material to material much more slowly than do the negative ion radii and the average electronic densities. [...]  Lire la suite

Various mechanisms that could yield proton radioactivity are discussed. The observation of this phenomenon is reported. The previously unreported nuclide Si25 beta decays to proton emitting excited states of Al25. The half-life of Si25 is 0.3 +0.2/-0.1 sec. Proton lines from the decay of Si25 dominate the delayed proton spectra following the bombardment of both 13Al and 14Si with 97 Mev protons. Si25 has (Z, N) of the form (2k+2, 2k-1) and is parent to a decay chain of the form: (2k+2, 2k-1) –(B+)-> (2k+1, 2k) – (p)-> (2k, 2k). It appears that bombardment of both element (2k+1) and element …  Lire la suite

Mason, S. (Supervisor)  Lire la suite

Paternal exposure to therapeutic drugs or environmental chemicals can alter the genomic integrity of male germ cells, and consequently, be a source of detrimental effects on embryo development. Preconceptional exposure of male rats to the anticancer alkylating agent, cyclophosphamide, resulted in increased embryo loss, malformations and behavioral deficits in the offspring; these drug effects can be transmissible to subsequent generations. The goal of the studies presented in this thesis is to gain an understanding of the manner by which altered spermatozoal genomic integrity, acquired during preconceptional exposure to a DNA damaging agent, may lead to developmental instabilities in the early …  Lire la suite

In an electromyographic (EMG) study of mirror tracing, Smith (27) found that muscle tension increased progressively during the task. He inferred that muscle tension is a function of the perceived distance from the goal, and that this relationship reflects a progressive increase in the organization of take directed processes in the central nervous system.  Lire la suite

Although we are mainly concerned with the psychological significance of muscle tension, it is important to bear in mind that this problem is but a part of a much broader one. The essential question before us is: What rationale underlies the study of physiological correlates of behavior?  Lire la suite

This study first investigated the association between individuals' chronic regulatory styles and their attachment models in adult close relationships, and then looked at how individuals' chronic regulatory styles interact with their attachment models to influence relationship maintenance strategies (RMS) such as accommodating one's partner's transgressions and making personal sacrifices for the relationship. One hundred twenty-one dating-students completed the computerized Selves Questionnaire (Higgins et al., 1997) assessing ideal and ought discrepancies and their chronic accessibility (promotion and prevention focus strength), and then answered questions addressing attachment, accommodation and willingness to sacrifice. Results revealed that ought discrepancies were associated with avoidant attachment …  Lire la suite

The early stages of a relationship present an interdependence dilemma: People want to demonstrate interest, but are reluctant because trust is not yet established (Holmes, 1991). Five studies investigated the influence of attachment on how people navigate the interdependence dilemma focusing on the use of communal and exchange norms (Clark & Mills, 1979). In Study 1, compared to secure and avoidantly attached individuals, anxiously attached individuals avoided using exchange norms with a potential friend, presumably to signal interest in closeness. In Study 2, when a potential friend used communal norms (compared to exchange norms), anxious individuals felt more anxious and …  Lire la suite

The inability to measure where an annihilation photon interacts within a detector crystal limits PET resolution uniformity by blurring the outer regions of the image. This problem is solved by dividing a scintillation crystal along its length into two regions, by a black absorbing band, that are equally likely to absorb a PET photon. Light collected from the front and back of the crystal allow the region of photon interaction and photon energy to be determined, using dual parameter acquisition. The design was tested by sweeping a radiation beam across a bismuth germanate crystal detector. The percentage of incorrectly positioned …  Lire la suite

Mongrain, Rosaire (Supervisor1)  Lire la suite

Although Expressed Emotion (EE) predicts relapse in Psychiatric Populations' the mechanisms through which people may be affected by high EE remain unknown. Our Objective was to test a model hypothesizing that reaction of young adults to critical comments (CCs) and emotional acceptance and perceived frequency of CCs and EOI. Path-analytical model were tested for 68 normal young adults living with their parents. Well-fitting models were found for reactions to Parental CCs but not for reactions to EOI. Results show that parental criticisms have only an indirect effect on young adults' reaction to criticisms: the effect is mediated by individuals' perception …  Lire la suite

[...] Since the latest evidence indicates that the toxicity in botulism is due to a decrease in the production of acetylcholine by motor end plates and parasympathetic nerve endings with the toxin having no direct effect on the muscle or conduction of nerve impulses through the nerve trunk itself, it was decided to attempt to further test this assumption and to determine the mechanism by which the decrease is brought about. [...]  Lire la suite

This case study examines the educational needs of students attending two social affairs schools in Quebec. The aim was to determine why these youths continue to do poorly academically and why they fail to thrive once they leave the child welfare system, as described in the literature. Individual and environmental factors that hinder academic progress were investigated ethnographically. The chronic under-achievement characteristic of youths attending the social affairs schools appears to be due to a number of individual factors such as frequent school changes as well as to the mental health model that guides the social affairs schools. This model …  Lire la suite

Au cours des deux dernières décennies, les inhibiteurs de kinases ont révolutionné le traitement du cancer. Cette révolution a été basée sur leur sélectivité pour des oncogènes responsables de la progression tumorale et de la résistance à la chimiothérapie classique. Malgré leur spécificité, ils sont capables de cibler plusieurs protéines de la même famille et même, d'autres familles de kinases Alors que par le passé, ce manque de sélectivité était perçu péjorativement, il est de plus en plus clair que l’efficacité des inhibiteurs multiciblés est supérieure à celle de ceux qui sont sélectifs. L’ensemble de leur cible comprend souvent plusieurs …  Lire la suite

As a debate over the legitimacy of the liturgical use of images, the Byzantine Iconoclastic controversy (ca. 726-843) had important political and theological implications, which modern scholarship generally tends to treat unconnectedly. The primary object of this study is to explicate the relationship between the political and theological dimensions of the controversy and to reconstruct the debate over images in a comprehensive approach that accounts for both its political and theological dimensions. The main argument of the thesis is that the question of images was a politico-theological problem and the prospects of 'political expediency' and 'theological propriety' were correlated in …  Lire la suite

The enzymic hydrolysis of organic phosphate esters was first noticed in the beginning of the twentieth century. The enzymes catalyzing this reaction were found to occur in many microorganisms and in most animal and plant tissues. In 1907 Suzuki, Yoshimura and Takaishi (1) reported that phytin was hydrolysed by an enzyme present in rice and wheat bran, which liberates inorganic phosphate. [...]  Lire la suite

In this research, the effects of gas composition, elapsed time of reaction and temperature on scale formation and descaling of low carbon steel were investigated and results were discussed from the viewpoint of the phase composition of the scales, oxidation rates, oxidation mechanisms, adhesion, fracture mechanics, porosity and residual scale. The phase composition and morphology of scales grown under conditions similar to those of reheating furnaces were analyzed. Low carbon steel was oxidized over the temperature range 1000-1250°C in gas mixtures of O 2-CO2-H2O-N2, O2-H 2O-N2 and O2-CO2-N2. The mole fraction of each phase, wustite (FeO), magnetite (Fe3O 4) and …  Lire la suite

La stabilité des pentes rocheuses est essentielle à la sécurité publique dans les autoroutes flanquées de rochers. L'instabilité de la pente et les effondrements de talus sont attribuables à de nombreux facteurs comme la géométrie défavorable des pentes, les discontinuités géologiques, les matériaux de talus mous ou patinés et les conditions météorologiques extrêmes. Les pressions externes comme les fortes précipitations et les tremblements de terre pourraient jouer un rôle important dans les effondrements de talus. Dans cette thèse, plusieurs systèmes de classification de masse rocheuse permettant d'évaluer la stabilité des pentes rocheuses ont fait l'objet d'un examen critique et ont …  Lire la suite

The objectives of the research are to: (1) Model and analyse the unique risk relationship between senior management and labour in environmental management; (2) Analyse various contractual mechanisms and compensation schemes that reduce the human resource management risk and minimise the dissonance between profit and stewardship goals; (3) Analyse the implications of the performance measurement problem on the principal-agent contract and the efficient delivery of abatement. Chapter 2 reviews literature pertinent to environmental management and the application of principal-agent theory. Chapter 3, entitled "Environmental Management Systems and the Intra-Firm Risk Relationship" is an analysis of the role of these incentives …  Lire la suite