McGill University Thèses et mémoires par auteur commençant par V

Cette thèse comprend deux volumes. Le premier est une analyse des techniques utilisées dansla composition de fragments of a grecian urn. Il est divisé en huit chapitres : introduction,texte, forme, mélodie, harmonie, rythme et temps, orchestration, ainsi que conclusions etpistes futures. fragments of a grecian urn explore la recontextualisation à travers le langagemusical, en mettant l’accent sur la fragmentation et l’imitation. Cela implique ledéveloppement d’outils compositionnels pour la fragmentation de la mélodie, du texte, de laforme et de l’instrumentation, de même que l’élaboration de ma propre approche del’ekphrasis musicale, générant du matériel musical qui met en valeur l’imitation entre les …  Lire la suite

In recent years, social media technologies and internet platforms have offered particularly generative possibilities for critical opposition. Online self-broadcasting platforms can act as mechanisms for community formation and archives of historical neglect, granting heightened visibility to longstanding and newly developing systemic issues. Located at the intersections of media studies, critical race theory, and Black feminist thought, Digital Kitchen Table Talks: Black Feminist Discourse in the Age of Social Media examines how Black women use digital platforms for self-expression, connection, education, and discussions on social and political issues, utilizing these platforms as virtual third places. Inspired by the work of influential …  Lire la suite

Les claudines (Cldn) sont une famille de protéines transmembranaires impliquées dans les jonctions serrées. Certains membres de la famille des claudines jouent un rôle important dans la fermeture du tube neural. La suppression de la Cldn4 et de la Cldn8 de l'ectoderme neural d'embryons de poulet a provoqué des anomalies de fermeture du tube neural (AFTN) dues à une défaillance lors de l'extension convergente et de la constriction apicale. La localisation des protéines à la surface de la cellule apicale de l'ectoderme neural a été perturbée chez des embryons pour lesquels les Cldn4 et Cldn8 ont été déplétés. La suppression …  Lire la suite

A number of investigators have suggested that the early and late phases of the formalin test are mediated by separate neural systems. Evidence is presented which suggests that in addition to a dissociation between the two phases based on nociceptor stimulation and inflammation, the late phase of the formalin test is also dependent upon plasticity in the central nervous system which occurs during the transient early phase. Selectively blocking neural activity during the early phase with local anesthetics given peripherally, or in the cingulum bundle or fornix, prevents the development of these changes. Locally anesthetizing the cingulum bundle, fornix or …  Lire la suite

The work reported here was aimed at extending previous findings suggesting that the medial and lateral substantia nigra (SN) are functionally different with regard to intracranial self-stimulation (ICSS) and circling. It was found that the effects of systemic D- and L-amphetamine on ICSS were different for medial and lateral SN sites. These differences were attributed to the presence of two subtypes of dopamine (DA) neurons in the SN. The circling results indicate that circling in opposite directions can be elicited from the medial and lateral parts of the nigrostriatal DA system from the same hemisphere suggesting that medial and lateral …  Lire la suite

A thematic and formal analysis of Jean-Aubert Loranger's poetic tale "Le Passeur" [1920], and of Gabrielle Roy's novel La Montagne secrete [1962], shows that the construction of the two heroes' respective identity is directly related to the representation of small and large rivers in the two stories. Considering the generic difference between the two texts, these similarities---which are shaped up in a four steps "organizing scheme"---suggest the existence of a real structure in the construction of the modern identity (quebecoise). La Grande traversee, an historical novel about the massive Irish emigration of 1847, narrates the quest of identity of Seamus …  Lire la suite

Phospholipids and lipopolysaccharide were purified from Haemophilus influenzae type b and combined by sonication to form liposomes which were impermeable to sucrose and to high molecular weight polysaccharides. When outer membrane proteins were incorporated into such liposomes, they became permeable to saccharides up to a molecular weight of about 1,400 daltons. The outer membrane proteins were fractionated on DEAE-Sepharose. Three protein-containing peaks were eluted from the column. Two of these peaks contained mixtures of proteins while the third peak contained only a single species of protein with a molecular weight of 40,000 daltons (40 kDa). When tested in reconstituted vesicles, …  Lire la suite

Ce memoire examine le rôle des fonctions à sens unique en cryptographie quantique. À cette fin, elle se penche sur les générateurs d’états quantiques pseudaléatoires, un concept récemment introduit par Ji, Liu et Song, qui sont analogues aux générateurs pseudaléatoires. Des travaux récents ont montré que ces générateurs peuvent être construits à partir de toute fonction à sens unique (sécurisée quantiquement) et peuvent être utilisés pour créer diverses primitives cryptographiques quantiques, telles que l’engagement de bit quantique, le chiffrement quantique à clé symétrique et les codes d’authentification de messages quantiques. Cela implique que, tout comme en cryptographie classique, les fonctions …  Lire la suite

Arbel, Tal (Supervisor2)  Lire la suite

La présente étude a comme sujet les transformations sociopolitiques dans la cite d'Ephesos dans la haute période hellénistique. Elle montre que pendant les mois tumultueux après la mort d'Alexandre le Grand, la communauté d'Éphèse a cherché à rétablir la stabilité interne et régionale en appelant aux Successeurs Macédoniens. Ce but a été atteint lors de la réunion a Ephese pendant l'été de 322 av-JC, comme il est atteste par un étude épigraphique détaillé d'une une série des inscriptions locales (I. Ephes. 1430-1437). La réunion a abordé des questions concernant la démocratie et privilèges Ioniennes, aussi que la hegemonia Macédonienne, en …  Lire la suite

The human nervous system is made up of billions of neurons that form precise connections allowing the smooth functioning of individuals in their day-to-day life. Even if a small proportion of these neurons miswire, it can have a major impact on how the brain develops, possibly resulting in neurodevelopmental disorders, such as autism. It is therefore important to establish how a healthy brain wires itself in order to gain insight into what goes wrong in disease. In order to further our understanding of how neural circuits in a healthy brain are formed, we use the mouse olfactory system as a …  Lire la suite

L'objectif global de ma thèse était d'étudier et de caractériser l'activité transcriptionelle du facteur de transcription CUX1, autant de façon globale que dans le contexte de processus cellulaires spécifiques. J'ai effectué des expériences de localisation génomiques à grande échelle afin d'identifier un grand nombre de cibles potentielles directes de transcription de CUX1 et j'ai analysé leur régulation par CUX1 en effectuant des expériences de profilage d'expression génétique à la suite de la surexpression de l'isoform p110CUX1 ainsi qu'à la suite de la répression de CUX1 par shRNA. Cette étude a démontré que CUX1 peut activer ou réprimer l'expression de ces …  Lire la suite

Une caractéristique d'une démarche saine est une attaque du talon dans laquelle le pied rentre en contact avec le sol, et ensuite se tourne dans le sens de l'avant du pied. Cette démarche est aussi appelée démarche talon-pointe. Cependant, une conséquence commune du vieillissement est la détérioration de la démarche talon-avant vers une démarche traînante ou orteils-avant. La physiothérapie peut être utile pour corriger cette anomalie, en revanche, le thérapeute est limité en temps et à l'environnement clinique. Une hypothèse de cette thèse est que la réadaptation de la démarche pourrait être prise en charge par l'utilisation d'un appareil qui …  Lire la suite

The Activated Sludge Process is the most widely used wastewater treatment process in the pulp and paper industry. Black liquor from the Kraft Pulping Process is characterized by high inorganic and organic load; it also contains toxic compounds. Upsets in the plant operation lead to disturbances in the activated sludge process and the process fails to produce effluents that meet regulatory standards. In this project, the effect of black liquor on the activated sludge was studied. Experiments were carried out in batch reactors and growth kinetics for the activated sludge were studied for each condition. In addition, the removal of …  Lire la suite

This thesis presents an implementation of a controller for a redundantly-actuated parallel mechanism. Firstly, an introduction to the structure and kinematic properties of the parallel mechanism is presented. We begin by describing the ASI hydraulic actuator, the main constituents of the mechanism, and move on to review the properties of the whole system. The inverse and forward relationships are derived, and the Jacobian matrix of the system is calculated using velocity analysis. The controller of the shoulder employs the above properties and relationships to balance for any external forces, in particular the gravity, and to estimate its magnitude. This is …  Lire la suite

Distributed source coding, separate encoding (compression) and joint decoding of statistically dependent sources, arises in an increasing number of applications like sensor networks and multiview video coding. Many of those applications are highly interactive, requiring the development of low-delay, energy-limited communication and computing schemes. Currently, this compression is performed by using capacity-approaching binary channel codes. As a natural extension, distributed lossy source coding is realized by cascading a quantizer and Slepian-Wolf coding in the binary domain. Despite big strides in practical distributed source coding techniques, this problem is still demanding in terms of processing power, bandwidth, and delay.In this dissertation, …  Lire la suite

Les lasers semi‑conducteurs à émission par surface (Surface‑Emitting, SE) sont aujourd’hui l’un des piliers essentiels des technologies photoniques modernes. Actuellement, ces lasers reposent principalement sur l’architecture des VCSEL (Vertical Cavity Surface‑Emitting Lasers), ayant connu un succès majeur dans le proche infrarouge (NIR). Cependant ils accusent un net retard aux longueurs d’onde plus courtes, en particulier dans l’ultraviolet (UV), où aucune technologie existante ne satisfait encore les exigences des applications pratiques. Un progrès décisif dans le développement des lasers SE UV est donc crucial, compte tenu de leurs applications potentielles dans des domaines touchant lavie quotidienne, tels que la désinfection ou …  Lire la suite

Giedde, Albert (Supervisor)  Lire la suite

Quantification of physiological functions with positron emission tomography requires knowledge of the arterial radioactivity concentration. Automated blood sampling systems increase the accuracy of this measurement, particularly for short-lived tracers such as oxygen-15, by reducing the sampling interval to a fraction of a second. They, however, require correction for tracer delay between the arterial puncture site and the external radiation detector (external delay), and for the tracer bolus distortion in the sampling catheter (external dispersion). We have evaluated and implemented the "Scanditronix" automated blood sampling system and measured its external delay and dispersion. PET studies of cerebral blood flow and oxygen …  Lire la suite

This thesis is organized to look upon the entire air transportation system with special emphasis in the circulation of Airport Terminals. In attempting to achieve an understanding of the problem, all the subsystems have been examined in depth. Considering the ground and VTOL/STOL access of the airport with the city, special considerating has been taken. Finally the target of the study has been concentrated in the area of interterminal transportation for passenger and cargo movements.  Lire la suite

Type 1 diabetes is an autoimmune disease characterized by destruction of the insulin-producing pancreatic beta-cells. Genetic predisposition, encoded by a number of loci, plays a large role in the probability of disease development. The IDDM2 susceptibility locus maps to the insulin gene (INS) variable number of tandem repeats (VNTR) minisatellite, which has two main clusters of alleles. As a whole, alleles of the class III cluster reduce the probability of developing type 1 diabetes and those of the class I cluster predispose to type 1 diabetes. To determine the functional basis of this susceptibility and protection, we tested the hypothesis …  Lire la suite

The sample included 29 healthy competitive male distance runners. Bilateral measurements were taken for selected variables of the talocalcaneal flexibility by means of a mechanical goniometer, and of the peak isokinetic knee strength on a Cybex II device. The frontal and horizontal plane motions of the lower limbs of the subjects were recorded by high speed filming and videotaping while they were running on a motor driven treadmill at their training pace under two conditions: with running shoes and barefoot. A detailed description of each runner's history was obtained and bilateral dominance characteristics were determined. Significant functional asymmetries were found …  Lire la suite

Research on plasticity in motor systems has for the most part developed separately from work on sensory plasticity, as if training-induced changes to the brain affected each of these systems in isolation. The aim of this thesis is to explore the association between the sensory and motor systems when a new skill is acquired. The experiments reported in this dissertation systematically examine two hypotheses about neuroplasticity: (i) that motor learning changes perceptual function and the function of somatosensory areas of the brain, and (ii) that somatosensory training changes both motor function and motor areas of the brain. The first study …  Lire la suite

Le présent travail porte sur le contrôle du processus de synchronisation d'une transmission manuelle automatisée sans embrayage du groupe motopropulseur d'un véhicule électrique actionné par un système de changement de vitesse électromécanique. En raison de la suppression de l'embrayage à sec classique dans la transmission du véhicule électrique, l'absence d'un système efficace de contrôle de changement de vitesses résulte en une forte usure des matériaux de friction de l'embrayage à cône du synchroniseur et réduit considérablement la durée de vie du système de changement de vitesse. Le synchroniseur est un mécanisme situé à l'intérieur de la transmission qui effectue le …  Lire la suite

Compulsory insurance to cover the carrier's liability in air transportation has been debated for a number of years. Notwithstanding the fact that the various international conferences have not, as yet, arrived at a definite decision, the discussion upon the subject matter is by no means closed.  Lire la suite

Five tachistoscopic studies were conducted to investigate patterns of hemispheric specialization for different types of word pair comparisons among monolinguals and fluent bilingual adults. Bilinguals were further grouped as "early" or "late" depending on whether their second language was acquired in infancy or in adolescence. All groups were faster at making orthographic comparisons for left visual field input but were faster in the right visual field for phonological and syntactic judgments. Semantic comparisons yielded no visual field asymmetries for monolinguals or late bilinguals but yielded a left visual field superiority for early bilinguals. Group differences in response strategy were also …  Lire la suite

McIntosh, Shane (Supervisor1)  Lire la suite

Les décisions les plus simples dépendent de notre capacité à filtrer l'information afin de sélectionner les options pertinentes. Toute machine distributrice, par exemple, déborde de boissons gazeuses aux étiquettes éclatantes de couleurs côtoyant des bouteilles d'eau et de jus aux allures plus sobres. Cet environnement complexe et multidimensionnel pullule de signaux sensoriels auxquels s'ajoute aussitôt un éventail d'actions possibles. Pour naviguer efficacement dans un tel environnement, une attention particulière doit être portée aux options disponibles ainsi qu'à leurs caractéristiques susceptibles de motiver nos décisions. Ces dernières années ont vu émerger un intérêt marqué envers les processus entourant la prise de …  Lire la suite

The object of this thesis is to present two novel applications of Spatiotemporal Image Correlation Spectroscopy (STICS) to biological systems. STICS is a technique which uses the correlations in pixel intensity fluctuations of an image time series, captured under fluorescence microscopy, to measure the speed and direction of a flowing population of fluorescently labeled molecules. The method was first applied to measure the dynamics of transport vesicles inside growing pollen tubes of lily flowers. The measured vector maps allowed to confirm the presence of actin filaments along the periphery of the tubes, as well as the presence of a reverse-fountain …  Lire la suite

The signaling properties of the p75 neurotrophin receptor (p75NTR) have been difficult to ascertain but new insights are emerging from a detailed characterization of cytosolic p75NTR interacting proteins. TRAF (Tumor Necrosis Factor Receptor-associated Factors) proteins are a family of cytosolic adaptors that link members of the TNF superfamily to the JNK, NF-kB and Src signaling cascades. We show, using a GST pull down assay, that TRAF4 binds the p75NTR intracellular domain with high affinity in the juxtamembrane region. Of the remaining TRAFs, only TRAF6 bound p75NTR and much less avidly than TRAF4. Co-expression of p75NTR with TRAF4 reduced the apparent …  Lire la suite

Cocaine use disorder (CUD) is a chronic relapsing brain disease that involves cycles of intoxication, withdrawal, and preoccupation. CUD impacts 1-2% of the population worldwide, and although there are multiple lines of evidence that report lasting changes in neurobiology, the mechanisms that accompany the development and maintenance of the disorder are not well understood. Work in animal models suggests that epigenetic mechanisms, including histone post translational modifications and DNA methylation, might be important regulators of cocaine-related changes to cell functioning, but to date, little is known about the relationship between cocaine dependence and epigenetics in humans.This thesis presents the first …  Lire la suite

Montaigne said it himself: "The titles of (his) chapters, embrace not always the matter" (Florio). In fact many of the 109 titles that comprise the three books of the Essais have nothing or little to do with the text they introduce. Why this lack of congruence? Where, when and how does it manifest itself? This study attempts to answer these questions in a diachronic and semiotic perspective. Starting with a typology of the various title functions--identificational, illocutionary, perlocutionary and contractual, the author proceeds to an analysis of the different title manifestations in the text and tries to demonstrate that the …  Lire la suite

Da Costa, Deborah (Supervisor2)  Lire la suite

The mechanisms underlying the net fluid/electrolyte gain during pregnancy are not fully understood. Utilizing virgin, pregnant (7, 16 and 21 days gestation), estradiol-17beta- or progesterone-treated female rats, we have examined the role of atrial natriuretic peptide (ANP) and of its receptors in the adaptation of body fluid homeostasis during pregnancy. Pregnancy and progesterone attenuate the ANP-mediated inhibition on aldosterone production in adrenal zona, glomerulosa (ZG) cells. The ribonuclease protection assay and Western analysis revealed that ZG natriuretic peptide guanylyl cyclase-linked (GC) receptors are mainly GC-A and that they are downregulated by pregnancy. In addition, pregnancy downregulates GC-A and GC-B receptors …  Lire la suite

Entrainment, extreme inhomogeneous mixing, in the presence of wind shear, and their effect on cloud droplet spectra are investigated. A dynamical model in conjunction with a microphysical model designed to predict evolution of cloud droplet spectra, is employed to perform a two-dimensional simulation of a small nonprecipitating cumulus cloud in the presence of wind shear. Results show that vortex circulations and penetrative downdrafts are responsible for entrainment of clear air into the cloud structure. Entrainment and mixing are more severe on the downshear side of the cloud leading to a more fragmented structure and often to total dissipation of cloudy …  Lire la suite

Traditionally, the diffusional growth of a cloud droplet population is calculated using values of the environmental conditions that represent averages over large volumes, the so called macroscopic conditions (Srivastava 1989). However, it is apparent that the growth rate of an individual droplet is a function of the temperature and the vapor pressure in its immediate environment. These quantities vary from droplet to droplet and with time in a turbulent medium such as a cumulus cloud. In most theoretical and numerical studies of clouds, the hypothesis is made that these variations are unimportant when calculating the growth of an ensemble of …  Lire la suite