McGill University Thèses et mémoires par auteur commençant par A

This research deals with acoustoelectric interactions in CdS. The first part is devoted to an experimental study of acoustoelectric effects occurring under high field conditions. An acoustic amplifier in which trapping effects are important is described, the decay time for current saturation is measured, and extreme non-uniformities in field distributions are measured and discussed. [...]  Lire la suite

Psychological stress may be a risk factor for essential hypertension. While several variables have been implicated as mediators or moderators of the relationship between stress and high blood pressure, their exact roles and level of importance remain to be elucidated. A key moderating variable may be family history of hypertension. A series of five studies examined the cardiovascular and emotional reactions to stress of normotensive individuals with and without a parental history of hypertension. In an attempt to facilitate the generalizability of the results, the studies used stressors with greater ecological validity than those used in most previous studies of …  Lire la suite

La respiration lente (SLOWB) est recommandée comme traitement adjuvant de l'hypertension. Cependant, la mesure dans laquelle les réponses de la pression artérielle (PA) à SLOWB diffèrent entre les hommes et les femmes n'est pas bien établie. Par conséquent, nous avons testé l'hypothèse qu'une poussée aiguë de SLOWB induirait des baisses plus importantes de la pression artérielle chez les hommes que chez les femmes, étant donné que les hommes ont généralement une pression artérielle au repos plus élevée. Nous avons également examiné les facteurs contribuant à l'autonomie réduite de la pression artérielle au cours de la SLOWB, c'est-à-dire l'activité nerveuse sympathique …  Lire la suite

Despite being abundant in the earth's crust, the concentration of Fe in many oceanic regions is so low that it is limiting to the growth of photosynthetic plankton. Heterotrophic bacteria play key roles in the oceanic cycling of carbon and nutrients, but it is unclear whether they can be Fe-deficient in nature, or what possible effects Fe-deficiency might have on their ecology and physiology. In chapter 1, I investigated the response of a natural bacterial community to a mesoscale Fe-enrichment experiment in the northeast subarctic Pacific. The addition of Fe to surface waters caused a rapid stimulation of bacterial growth …  Lire la suite

Proper Orthogonal Decomposition (POD) is a technique which has been used successfully to reduce the computation time in various fields of engineering. Here POD is applied to electromagnetic field computations, specifically to the simulation of electromagnetic diffusion by the time-domain finite element method. The standard method requires a large matrix equation to be solved at every time step. POD is applied to greatly reduce the size of the matrices. Both 1-D and 2-D test cases are considered. Applying POD reduces the matrix dimension for a 2-D problem from 2,535 to just 5, with negligible loss of accuracy.  Lire la suite

Coupled walls are among the most commonly used seismic force resisting systems within mid-to-high rise reinforced concrete structures in Canada. Coupling beams are a crucial component of the coupled wall system due to their effective energy dissipation capabilities and high ductility. In situations where coupling beams have a span-to-depth ratio greater than 4.0, conventional longitudinal reinforcement and transverse hoops are typically used to resist the applied moments and shear forces. The 2014 version of the CSA A23.3 Standard provides specific hoop spacing requirements which help ensure that flexural members subjected to seismic loading are designed to avoid brittle failure modes. …  Lire la suite

Mechanisms to share information from Mechanical Computer Assisted Design (MCAD) to simulation model have been demonstrated using various approaches. However, in all cases the information sharing is unidirectional - from the MCAD to Multi-Body Systems (MBS) simulation - which lacks the bidirectional mapping required in a concurrent engineering context where both models need to develop in parallel while remaining consistent.We present a modelling library and a model mapping that permits and encourages parallel development of the mechanical assembly in both the MBS simulation and MCAD environments while supporting both bidirectional initial full transfer and incremental updates. Furthermore, with the adopted …  Lire la suite

The works of jurist Louis Le Caron (1534-1613) are part of a body of doxological writings by a school of humanists who repudiated Aristotelian scholasticism. In the Dialogues (1556), Le Caron elaborated a theory of poetics as well as a vision of the cosmos and of man encompassing political, aesthetic, ethical and epistemological perspectives. The Dialogues can be regarded as an example of absolute idealism because their philosophical underpinnings echo the neo-Platonic tradition. This being said, the way the book's arguments are organized into dialogues demonstrates an ideological shift which, in the middle of the century, progressively undermined the current …  Lire la suite

This thesis critically investigates patent protection of medicines in light of the threats posed by HIV/AIDS, malaria and tuberculosis epidemics to the citizens of countries in Sub-Saharan Africa (hereinafter SSA or Africa). The thesis begins by outlining the systemic problems associated with the prevailing globalized patent regime and the regime's inability to promote access to life-saving medicines at affordable prices in poor regions such as SSA. The thesis then goes on to argue that for pharmaceutical patents to retain their relevance in SSA countries human development concepts must be integrated into global patent law- and policy-making. An integrative approach here …  Lire la suite

The blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) signal, the most commonly used imaging technique to identify localized changes in brain activity, has been shown to exhibit certain transient characteristics that are poorly understood by the medical imaging community. This thesis is aimed at investigating the origins of the post-stimulation signal undershoot phenomenon, a prolonged (~30s-1min) drop below baseline of the BOLD signal after the cessation of neuronal stimulation. Three alternate theories exist regarding the physiological changes responsible for the BOLD undershooting. The first theory suggests that prolonged elevation in the cerebral metabolic rate of oxygen (CMRO2) …  Lire la suite

To supplement the non-renewable energy sources which are heavily relied-upon today, much research is being done to develop environmentally-friendly "Green Energy" and biologically-based "Bio Energy".The potential of microbial fuel cells (MFCs) as one of these next-generation energy sources was the first of two main aspects of this Master's research. Their suitability as a waste valorization by means of bioelectricity generation was investigated. The study employed a 50ml, single-chamber MFC system to compare substrate removal and electrical production using both minimal media and waste media derived from a glycerol process described by Jitrwung and Yargeau in 2010, both containing lactic acid …  Lire la suite

Four groups of Canadian adolescent boys, varying with regard to the Frenchness or Englishness of their ethnic background, were compared on a series of social-psychological characteristics. Two groups were of mixed ethnic parentage, one group attending English Catholic schools in Montreal and the other attending French schools. A questionnaire was administered designed to measure anomie, authoritarianism, ethnocentrism, achievement value orientations, occupational aspirations, identification with parents and ethnic groups, self-image, and perceptions of parents' behavior and one's own social behavior. The mixed-ethnic subjects attending English language schools identified themselves as English Canadians in spite of a demonstrable attachment and liking for …  Lire la suite

This thesis explores new methods of representing the electromagnetic forces in any electromechanical or electromagnetic devices using "off-the-shelf" equipment. It also explores the usefulness of these methods in the design process of such devices and in the understanding of electromagnetic forces. Finally, the thesis concentrates on an investigation of haptics as a new method of allowing the user to 'feel' the electromagnetic forces. The thesis describes the design of a system that involves the software development of Graphical User Interface (GUI) to represent the design, with its electromagnetic flux lines, together with a choice of a commercial haptic device to …  Lire la suite

Cerebrospinal fluid (CSF) is a fluid containing nutrients and a variety of factors, andcells in the brain and spinal cord are constantly immersed in CSF. In the brain, there arecavities which hold CSF, called ventricles, and ependymal cells are a population of cellswhich constitute the barrier between CSF and the brain within the ventricles. Beyondtheir function mediating this barrier, they are also ciliated and their cilia are known toplay a role in the circulation of CSF across the ventricular system. Multiple sclerosis(MS) is a chronic neuroinflammatory disorder characterized by the presence demyeli-nating lesions in the central nervous system (CNS). Recent …  Lire la suite

By combining a descriptive meihod with a comparative one, this thesis attempts to understand the ideas of method of Muslim learning as illustrated in a medieval Muslim treatise, Ta'lim al-Muta'allim Tariq al-Ta'allum (Instruction of the Student: the Method of Learning), of Burhan al-Din al-Zarnuji (flourished circa 620/1223). It is apparent throughout the present study that the method of Muslim learning is not simply a technique by which a student seeks to deal, in an appropriate manner, with any academic assignment, but rather, an approach, the very heart of which rests on the problem of ethics, which brings a student into …  Lire la suite

Two major subtypes of nicotinic acetylcholine receptors (nAChRs) have been identified in the nervous system. One site is bound by $ alpha$-bungarotoxin ($ alpha$-BGT), while the other has a higher affinity for agonists and does not bind the $ alpha$-toxin. Muscle nAChRs, which also bind $ alpha$-BGT, had been reported to be sensitive to a thymus-derived polypeptide, thymopoietin (TPO). The present work was therefore done to determine whether this agent might also interact with the different nAChR populations in neuronal cells. Initial studies involved thymopentin (TP-5), a 5 amino-acid peptide which may represent the active site of TPO. TP-5 inhibited …  Lire la suite

This research is based on the hypothesis that by permanently immobilizing Fibronectin (FN) on a metal substrate surface, it will be possible to enhance endothelial cells (EC)/surface interactions. FN was covalently bound onto self assembled monolayers (SAMs) modified gold surfaces with COOH terminal groups. SAMs composed of various surface ratios of X/COOH (X=CH3, OH, NH2) were formed in order to control the surface conformation of FN by modulating the surface charge (potential) and wettability. Human umbilical vein endothelial cell (HUVEC) attachment and proliferation onto such surfaces was investigated. Results have shown that SAM and SAM-protein surfaces are stable with time. …  Lire la suite

Bantwal Baliga (Internal/Cosupervisor2)  Lire la suite

Sladeczek, Ingrid (Internal/Supervisor)  Lire la suite

Cette étude examine les attentes mutuelles des conseillers pédagogiques en mathématiques (CPM) et des enseignants envers leur participation dans un projet de recherche collaboratif. Pour étudier cette collaboration, deux CPM et neuf enseignants ont répondu à un questionnaire concernant les buts de participation au projet et l’identification de leurs rôles et leurs attentes envers leur participation dans le projet de recherche collaboratif. Les écrits scientifiques décrivent un modèle à trois étapes pour la recherche collaborative : la co-situation, la co-opération et la co-production. Les buts et les motivations peuvent être redéfinis tout au long de ces trois stages. Toutefois, une …  Lire la suite

This thesis is an attempt to study the role of Ahmad Surkati in al-Ishrad movement in Java and its implications for the Arab community in Indonesia.  Lire la suite

This thesis is an attempt to study the role of Ahmad Surkati in al-Irshad movement in Java, and its implications for the Arab community in Indonesia. Surkati was a Sudanese Muslim scholar who, in 1911, came to Indonesia as one of the Islamic teachers invited by Jamiat Khair, an Arab organization, which was established in Jakarta in 1905. The fact that the Hadrami Arabs were divided into two groups, the sayyids who enjoyed elevated position and the non-sayyids, urged Ahmad Surkati to propagate the idea of equality among Muslims. Thus, in 1913 Surkati sponsored the foundation of an Arab organization …  Lire la suite

Les changements anthropiques rapides exercent une pression sans précédent sur les écosystèmes, réduisant leur capacité à fournir des services essentiels au bien-être humain. Alors que les accords internationaux préconisent de plus en plus la surveillance systématique de ces services écosystémiques, les progrès sont entravés par l'ambiguïté conceptuelle, la fragmentation des données et le manque d'outils opérationnels permettant de détecter et d'attribuer les changements. Cette thèse aborde ces défis en développant et en testant empiriquement des outils fondamentaux pour la mise en place de systèmes intégrés de suivi des services écosystémiques, en utilisant le contexte canadien comme terrain d'essai. Tout d'abord, …  Lire la suite

Guzder, Jaswant (Supervisor2)  Lire la suite

Macdonald, Mary Ellen (Internal/Supervisor)  Lire la suite

Manges, Amee (Internal/Supervisor)  Lire la suite

Tremblay, Robert (Supervisor2)  Lire la suite

Boivin, Jean-Francois (Supervisor1)  Lire la suite

Prakash, Satya (Internal/Supervisor)  Lire la suite

Cardiac arrhythmias remain a leading cause of mortality for patients afflicted by cardiac diseases, such as heart failure (HF). Sudden cardiac death is implicated in ~50% of deaths in HF, and remodeling of ion channels further leads to lethal arrhythmias. Neurohormonal activation plays a significant role in cardiac remodeling and progression of the disease. In this thesis, I investigated the role of exchange protein directly activated by cAMP (Epac) in cardiac remodeling.HF is associated with an increase in adrenergic drive, with plasma norepinephrine concentrations predictive of mortality outcomes. Reduction in the slowly activating delayed-rectifier potassium current (IKs) is commonly observed …  Lire la suite

Gotman, Jean (Supervisor2)  Lire la suite

The global telecommunications environment is undergoing rapid and radical transformation. Liberalisation in the industrialised economies, prompted by the fast pact of innovation in telecommunications technology has spilled over to developing countries, which now realise the significance of telecommunications for socio-economic development within their economies. The most significant aspect of these developments is that it has led to the liberalisation of telecommunications companies and the opening up of market access under the auspices of the World Trade Organisation. There is now open competition in a glob al telecommunications industry. Multinational companies equipped with the state-of-the-art technologies, ample experience and service skills, …  Lire la suite

Abi-Nader, Samer (Internal/Cosupervisor2)  Lire la suite

The activity coefficients for the solutes at high dilution in twenty-four non-reacting binary nonaqueous liquid mixtures were determined experimentally by gas chromatographic analysis of the equilibrium vapor phase. Excess partial molal heats of mixing for the same systems in the dilute concentration range were also obtained, by a conventional microcalorimetric technique. […] Finally, the excess thermodynamic properties are discussed in terms of solute-solvent interactions, molecular orientation, and energy of cavity formation.  Lire la suite

Turbulent mixing, which leads to dilution or chemical reactions (including combustion) at a molecular level, is studied using a passive scalar. Khorsandi (2013) and Perez-Alvarado (2016) studied the velocity and concentration fields of an axisymmetric turbulent jet in zero mean flow, respectively, in a quiescent and turbulent ambient. The aim of the present study is to extend this work observing a turbulent jet released into a nearly homogeneous isotropic turbulent background with negligible mean flow created with a random jet array. The characteristic of the jet in a turbulent background flow is compared to that released into a quiescent background. …  Lire la suite

A reasonable representation of some complex systems such as social and biological systems is a network topology that allows its components and interactions among them to change over time. Understanding the time-dependence of these networks can lead to invaluable insight about characteristics and structure of time-varying networks. In this thesis, several classes of static and dynamic clustering algorithms and ideas are reviewed. A challenge arising in dynamic clustering schemes is that the detected communities are not independent over time and the identified clusters at one point of time should not dramatically deviate from the results of previous timesteps. It is …  Lire la suite

Cette thèse porte sur l'étude de la modélisation d'un matériau récemment découvert, appelé graphène, dans les méthodes du domaine temporal. Premièrement, une approche générale dans le domaine temporel à différences finies (FDTD) suivie par des équations de mise à jour FDTD prenant en compte le graphène est introduite. Par la suite, une nouvelle formulation FDTD pour la modélisation du terme de conductivité intra-bande du graphène est proposée, dans laquelle le graphène est modélisé comme une feuille résistive avec une conductivité dépendante de la fréquence. La formulation est d'abord développée dans le contexte du domaine temporel à éléments finis (FETD) de …  Lire la suite