McGill University Thèses et mémoires par auteur commençant par B

A high frequency, large amplitude helium filled RFQ (Radio Frequency Quadrupole) beam cooler and buncher was developed and tested for use in the TITAN (TRIUMF's Ion Trap for Atomic and Nuclear science) Penning trap mass spectrometer facility. This device will cool and bunch radioactive ion beams for use in TITAN's high precision mass measurements of short-lived isotopes and other experiments. A test stand was built to test the transmission and properties of ions from a surface ion source through injection optics, the linear Paul trap RFQ and the extraction optics in both continuous and pulsed modes. The efficiency of the …  Lire la suite

The influence of phonatory transitions on stuttering was examined in a group of 14 young adult stutterers. Subjects performed five oral readings of two passages, one containing all-voiced sounds, and the other both voiced and voiceless sounds. Results showed, in contrast to a previous study by Adams and Reis (1971), that more stuttering was associated with the all-voiced passage and that rate of adaptation was similar for both passages. Adams and Reis's method of comparing passages appeared to be misleading, since a strong context effect was found in the present study or frequency of stuttering on voiced to voiced transitions, …  Lire la suite

Range limit theory contextualizes the evolutionary and ecological processes that limit species' distributions, and can be especially useful when studying edge populations of species at-risk to diagnose potential limitations of population success. Theory predicts that habitat quality declines toward range-edges, resulting in edge populations that are smaller, less dense, and have lower individual performance than core populations. These predictions have important implications for edge populations' conservation value and needs, though they need to be empirically tested as much variation exists among species range limits. Simultaneously assessing demography and habitat quality towards the range edge allows us to quantify interacting factors …  Lire la suite

Hendry, Andrew (Supervisor1)  Lire la suite

Students with learning disabilities (LD) have been found to exhibit social difficulties compared to those without LD (Wong, 2004). Recognition, expression, and understanding of facial expressions of emotions have been shown to be important for social functioning (Custrini & Feldman, 1989; Philippot & Feldman, 1990). LD subtypes have been studied (Rourke, 1999) and children with nonverbal learning disabilities (NVLD) have been observed to be worse at recognizing facial expressions compared to children with verbal learning disabilities (VLD), no learning disability (NLD; Dimitrovsky, Spector, Levy-Shiff, & Vakil, 1998; Dimitrovsky, Spector, & Levy-Shiff, 2000), and those with psychiatric difficulties without LD controls …  Lire la suite

Environ 2 millions de nouveaux cas de cancer colorectal sont diagnostiqués chaque année dans le monde, et environ la moitié de ces patients meurent de la maladie. Le mauvais pronostic de ces patients est principalement dû à la propagation métastatique, le foie étant l'organe le plus souvent touché. En raison de la gravité et de la prévalence de cette maladie, il est nécessaire de développer de nouvelles stratégies de traitement. L'immunothérapie est l'un des domaines explorés, car elle s'est révélée révolutionnaire pour de nombreux types de cancer. Malheureusement, à l'exception d'un petit pourcentage de patients, l'immunothérapie s'est révélée inefficace pour …  Lire la suite

This is one section of a pilot study conducted jointly by a team consisting of a physician, two psychiatrists, a psychologist and four social workers. The purpose of the study is to gain further information regarding the part played by multiple stresses in bringing about rheumatoid arthritis. Four social workers took part in the study. Each one interviewed twenty patients with the diagnosis of rheumatoid arthritis according to a plan structured in co-operation with the psychiatrist.  Lire la suite

An original method la devised here and instrumentated for the measurement of heat transfer from precipitation particles (particularly liquid drops) to the atmosphere when the particles are falling at their terminal velocities. The results of the measurements made by this system are compared to what simple theory predicts. A qualitative discussion is made of the reasons for the discrepancy. The shortcomings of the general measurement method are discussed and suggestions are made for extension and improvement of the system. Heat transfer data for various drop sizes at terminal velocity and for an artificial snow-flake are presented.  Lire la suite

This work develops a new approach to female strip dancing as cultural practice by using methods of cultural history, ethnographic field work and theoretical critique in order to reconstruct the historical setting in which strip dancing emerged, the varied sites where it continues to evolve, and the diverse interpretations of strip by its different practitioners. Toward this end, the dissertation is divided into five major sections which link such forms of body movement and display to wider socio-historical movements of theory and practice; sexuality; commerce; pleasure and power; and culture. It is then concluded that such small-scale or "stripped-down" studies …  Lire la suite

The proton nuclear magnetic resonance was observed in NH4Cl at -195°C. The line shape was interpreted in terms of nuclear spin, nuclear g-factors and lattice parameters of NH4Cl according to the theory of Van Vleck. From these considerations, the N-H distance in NH4Cl was measured as 1.075 ± 0.015 A0. A correction factor for the effect of the modulation field on the line shape has been derived and applied to the results of other experiments of the same type.  Lire la suite

Human subjects were asked to "fixate" an earth-stationary target, in complete darkness, either during or after a brief passive head rotation. During head rotation saccadic eye movements synergistically improved compensatory slow-phase vestibulo-ocular reflex (VOR) stabilization. Visual-vestibular conflict that adaptively attenuated VOR gain caused the combined saccadic and slow-phase response to undercompensate for head rotation. Saccades volitionally generated after the cessation of head rotation (Vestibular Memory-Contingent Saccades, VMCS), successfully acquired the earth-fixed target, indicating that perceived vestibular information has access to the saccade generating mechanism. The above adaptive stimulus contracted the amplitude of VMCSs, suggesting a commensurate modification of the percept …  Lire la suite

A faster, more efficient method has been developed for preparation of a copper-protein similar to Mann and Keilin's hepatocuprein. Beef liver is homogenized in glass-distilled water. The water-soluble fraction, prepared by centrifugation at 105,000 g, is heated at 50° for 10 minutes and recentrifuged. Residual soluble protein is precipitated with acetone. On redissolving in 0.005M K-phosphate buffer, pH 7.0, the material is passed through Sephadex G-75 and fractions with a high copper:protein ratio are pooled. These fractions are colorless. They contain three protein components (electrophoresis in acrylamide gel at pH 8.9) which appear to have molecular weights (gel filtration) of …  Lire la suite

The distribution of copper among the proteins of rat-liver cytosol was studied with Sephadex G-75. Analysis of the Sephadex profiles showed that copper is distributed differently within the cytosol of normal rats and those whose copper levels have been increased by intraperitoneal injection of copper. Distribution of copper in cytosol of neonatal rats is similar to that for copper-loaded, adult rats. The uptake of copper into the cytosol is an ordered process which cannot be reproduced in vitro. In normal cytosol the major portion of the copper co-chromatographs with proteins of 40,000 daltons. After rats have received injections of copper …  Lire la suite

It was some 38 years ago that Sir William Crookes, eminent British scientist, in the first edition of his book, ""The Wheat Problem" predicted theinevitability of a long-run increase in the price of wheat. This grim prospect arose, he contended, due to the rapidlY diminishing supply ofavailable wheat land, which, according to him, would soon be inadequate to provide for the world's needs. Within an appreciable distance, hepredicted a scarcity of this vital foodstuff. [...]  Lire la suite

"Recent criticism of 'Piers Plowman' has done more to weaken the hold of opinions once generally accepted than to replaoe them by others better founded". Kenneth Sisam in his "Fourteenth Century Verse and Prose" makes the above statement in the introduction to his selection from that poem. [...]  Lire la suite

Experiments to test the action of 2£ constituents of urine on the free living stages of horse sclerostomes showed that only five were toxic: urea, ammonia, hippuric acid, benzoic acid and sodium bicarbonate. Benzoic acid was lethal to ail three stages: ova, preinfective larvae and infective larvae, the others being lethal to preinfective larvae only.The time required to kill £0 percent of the preinfective larvae was: urea - $0 hours; ammonia - 31 minutes; hippuricacid - $2 minutes; benzoic acid - 19 minutes; sodium bicarbonate - h3 hours; and of ova and infective larvae was: benzoic acid - 18 minutes …  Lire la suite

Selling and salesmanship are now among the universals of culture on this continent. Although much is known about the mass effects of salesmanship, relatively little knowledge exists on the nature of the face-to-face selling situation. It is an interpersonal situation, involving the interaction of two or more actors: salesman and customer(s). The specific purpose of this interaction is the transfer of a commodity. These facts seem familiar and taken for granted.  Lire la suite

The problems involved in the design of a transistor operational amplifier suitable for a repetitive computer are discussed. An analysis of parallel feedback applied to an active quadripole is advanced to show that the maximum computing accuracy for a given number of transistors is obtained by employing cascaded, common-emitter stages without local feedback. The factors which determine the bandwidth of a repetitive computer amplifier are discussed and the associated stability problems are solved by appropriate shaping of the loop transmission of the amplifier. [...]  Lire la suite

There has been a significant quantity of research focusing on the topic of cortical reorganization in human evolution, but much less is known regarding the reorganization of subcortical circuits which are intimate working partners of the cortex. Here, by combining advanced image analysis techniques with comparative neuroimaging data, we systematically map organizational differences in striatal, thalamic and pallidal anatomy between humans and chimpanzees. We relate interspecies differences, a proxy for evolutionary changes, to genetics and behavioral correlates. We show that highly heritable morphological measures are significantly expanded across species, in contrast to previous findings in the cortex. We then used …  Lire la suite

It was appreciated at the beginning of this project that any real advancement in the technique of blood preservation would likely come from an understanding of the energy metabolism of the red blood cell (erythrocyte or normocyte). Until about twenty-five years ago this cell was regarded as being little more than a parcel of hemoglobin. Lacking a nucleus and other common cell components, it was regarded as merely a transporter of oxygen and carbon dioxide. [...]  Lire la suite

Dasgupta, Kaberi (Internal/Supervisor)  Lire la suite

Les enzymes de synthèse de peptides non ribosomiques (NRPSs) sont un groupe d'enzymes multi-modulaires qui synthétisent de nombreux peptides très diversifiés, tant structurellement que fonctionnellement, dont certains s'avèrent être d'intéressants métabolites secondaires. Les NRPS s'organisent comme une chaîne de modules d'environs 1100 résidus, où chaque module a pour rôle d'incorporer spécifiquement un acide aminé dans le peptide non-ribosomique ainsi produit. Dans la plupart des cas, un module de NRPS est composé de 3 domaines essentiels à l'élongation du peptide non-ribosomique : le domaine d'adénylation (A), le domaine porteur de peptide (PCP) et le domaine de condensation (C). Chez certains NRPS, …  Lire la suite

Mise en contexte: Les géohelminthiases sont des parasites intestinaux qui posent une charge de morbidité importante. Il a été proposé que les géohelminthiases affectent le développement de l'enfant, par un mécanisme susceptible d'être lié aux taux de fer. Des recherches limitées ont été entreprises sur ce sujet chez les enfants d'âge préscolaire et la nécessité de développer une meilleure compréhension du lien entre les géohelminthiases et le développement de l'enfant a récemment été soulignée. L'objectif général était de déterminer si, et comment, les géohelminthiases affectent le développement de l'enfant chez les enfants d'âge préscolaire.Méthodes: Une étude longitudinale de cohorte a …  Lire la suite

Des études ont démontré que retarder la coupure du cordon ombilical pourrait réduire les risques d'anémie infantile. Un plan d'étude pré/post a été utilisé pour déterminer l'efficacité d'une intervention visant à retarder la coupure du cordon. Des femmes ont été recrutées à l'Hôpital Iquitos (Pérou) pré- (N=112) et post-intervention (N=112). Le statut hématologique des mères a été quantifié, le moment où le cordon est coupée a été chronométré et le niveau d'hémoglobine des enfants à été mesuré. La coupure du cordon a été retardée de manière significative de 113 secondes suite à l'intervention (βajusté=113.2 secondes; 95% IC =96.6-129.9). L'anémie maternelle …  Lire la suite

Graff, W. (Supervisors)  Lire la suite

Avec ses deux rangées de coquillages violets tissés sur un fond blanc, le Teiohá:te (wampum à deux rangs) symbolise une rivière sur laquelle voyagent côte à côte le canoë des autochtones et le navire des colons. Préservant la mémoire d'une alliance entre les Rotinonhsión:ni (Iroquois) et les premiers colons hollandais, ses lignes parallèles suggèrent que les deux communautés ne peuvent avancer dans la même direction que si elles demeurent sur des voies parallèles et s'abstiennent d'empiéter l'une sur l'autre. Ma thèse explore cette conception paradoxale de « l'alli-ance à travers la séparation » par le biais d'un travail de terrain …  Lire la suite

La stratosphère est une couche de l'atmosphère active et sujette à d'impressionnantes perturbations à grande échelle, particulièrement en Arctique et durant l’hiver. L'une de ces perturbations est connue sous le nom de réchauffement stratosphérique soudain (sudden stratospheric warming - SSW). Un SSW est marqué par une perturbation du vortex polaire, une inversion des vents zonaux et une augmentation de la température dans la stratosphère. Dans certains cas, les températures peuvent augmenter de plus de 50 K au-dessus de la normale en l'espace de quelques jours. Étant donné l’impact potentiel de ces perturbations sur le profil de température de la stratosphère, …  Lire la suite

Built upon work addressing the “poet-critic” in modernism (Kindley, 2017) and guided by work associated with the New Formalism, this thesis explores the development of critical exchanges in verse within modernist communities, theorizing how Ezra Pound, W.B. Yeats, and Marianne Moore engaged in critical conversations with one another by way of formal allusion— especially sound and rhythm—generating commentary on one another’s poetry and poetics. My thesis traces the expansion of this modernist conversation-in-poetry, beginning with Pound’s commentary through poetic form as critique of early Yeats’s nationalist poetics. The second chapter explores the development of Pound’s criticism during the Stone Cottage …  Lire la suite

L'oscillateur circadien principal, situé dans le noyau suprachiasmatique (NSC), s'ajuste aux cycles jour-nuit et communique cette information à travers le cerveau et le corps, afin de moduler les processus physiologiques et comportementaux selon les rythmes environnementaux. La sensibilité aux signaux entrants, la précision et la robustesse de l'oscillateur, et les voies de sortie de celui-ci reposent sur un réseau de neurones dans le NSC. Notre hypothèse était que ce réseau est rendu possible grâce à des sous-populations spécifiques de neurones délimitées par l'expression du neuropeptide. Par ablation ou résurrection sélective d'horloges circadiennes moléculaires dans l'une de ces sous-populations, exprimant le …  Lire la suite

A modified method is described for the measurement of transference numbers. The general applicability of the liquid junction technique of Elias and Schiff to equivalent conductance measurements suggested that the use of liquid junctions in the moving boundary method of Lorimer, Graham and Gordon would allow transference numbers to be measured in any electrolyte. [...]  Lire la suite

Macallum, A. (Supervisors)  Lire la suite

On a observé les enregistrements extra-cellulaires venant des neurones de l’hypothalamus médian pour démontrer les connexions avec l’éminence médiane, la tige pituitaire, le septum latéral, l’amygdale, la région pré-optique hypothalamique antérieure et “PAG”. Des programmes d’ordinateur interactifs et des programmes et données de base out été utilisés pour l’analyse des résultats. On a démontré que certain certains neurones tubéro-infundibulaires identifies par la projection de leur axone ver l’éminence médiane se divisent en plusieurs branches vers la tige pituitaire. […]  Lire la suite

In recent years the need for greater transparency within international organizations has been a focal point for the international community. The result of numerous debates has represented significant changes of the public information disclosure policies of organizations' programs, resolutions, and decisions. The International Civil Aviation Organization has been a pioneer and innovator in this respect. Not only the vast majority of its documentation is accessible to the public, but also it has transformed one of its surveillance programs into a window of information for the international aviation community. The disclosure of the Universal Safety Oversight Audit Programme's information has generated …  Lire la suite

Kemp, H. (Supervisors)  Lire la suite

According to UNICEF (2012) four in thirty (13%) children in Canada live in poverty. Aside from being a specific threat to social justice, childhood deprivation is associated with poor development outcomes, some of which may persist into adulthood. Asset poverty, while explored in other contexts and countries, has not been explored as much in Canada as income poverty has. There is good reason to suspect that assets have important effects on children independent of income, and a wide research gap exists in this area in Canada. This thesis explored the prevalence and predictors of asset poverty in Canadian families with …  Lire la suite

The short story represents one of the most interesting paradoxes in literature; for while it is one of the oldest of literary forms, it is also one of the most recent. The art of brief narration is as old as the Book of "Ruth," the "Cupid and Psyche" of Apuleius, "The Matron of Ephesus" of Petronius, and "The Pardoner's Tale" of Chaucer; and yet it is as new as Poe and Maupassant, as Chekhov and Katherine Mansfield, as Anderson and Hemingway; as new, in fact, as the latest product of the experimental magazine. [...]  Lire la suite

The presence of circulating antibody long after the injection of antigen, i.e. viruses, toxoids and bacterial polysaccharides, has frequently been observed. Until recently, however, antibodies produced in response to primary immunization with innocuous soluble protein antigens have been detected in the circulation for relatively short periods of time. It is to be noted that the main types of antibody sought for in these experiments have been precipitins. [...]  Lire la suite

The purpose of this study was to examine the relationships among several demographic and emotional/relational variables, and physical abuse victimization in conjugal relations. Participants were eighty-two individuals, involving 41 heterosexual couples in permanent relationships, who were being seen in marital therapy for discordant relationships. This was a cross-sectional sample, with participants selected from four community-based couple and family therapy treatment facilities. Couple participants completed a questionnaire package which measured their standing on a number of socio-demographic (age, income, duration of marriage, employment, education), emotional/relationship (attachment, differentiation, self esteem, marital satisfaction, global distress, problem solving communication), and violence (aggression, physical and …  Lire la suite

Background: Dietitians in Quebec, Canada, who are active members of ODNQ (l’Ordre des diététistes- nutritionnistes du Québec) now have the rights to adjust antihyperglycemic agents and insulin for people living with diabetes (after completing an online training and exam). In response to the current diabetes increase need for care, dietitians have a key role to play. Mentorship in diabetes for dietitians might be an option to help build or solidify confidence levels, grow the profession and with the overall goal of helping more people living with diabetes. Mentorship for healthcare professionals is used to offer guidance, knowledge and experience transfer, …  Lire la suite

The soleus H-reflex modulation pattern was measured in 8 normal and 8 spastic paretic subjects during standing and walking, under the conditions of 0% and 40% body weight support (BWS). In standing, both the normal and patient groups showed no significant difference (p $<$ 0.01) in the H-reflex amplitude between 0% and 40% BWS. Normal subjects had a phase dependent modulation of the H-reflex during gait, there being no significant difference (p $<$ 0.001) in this modulation with 40% BWS. The patients had an abnormally elevated H-reflex throughout the step cycle, although five showed some modulation. In the patient group, …  Lire la suite

This thesis reports the results of an investigation of scorodite long-term solubility and stability conducted at fixed pH (5-9) and temperature (22°C, 50°C and 75°C). The decomposition of scorodite at 22°C was found to be extremely slow. At neutral pH, the arsenic concentration stabilized at 5.8 mg/L. As scorodite dissolved, the iron reprecipitated as 2-line ferrihydrite. The growth and re-crystallization of ferrihydrite was delayed by apparent arsenate adsorption. The solubility product of scorodite was calculated as 10-25.5. The dissolution rate of scorodite in a pure system was modeled with a decreasing exponential equation. The pre-exponential factor approached first order vis-a-vis …  Lire la suite

Les engrais phosphorés sont nécessaires afin de maintenir et d’améliorer la productivité agricole. Une des technologies ayant permis d’augmenter la productivité des terres est l’apparition d’engrais. Depuis le Néolithique, les engrais ont été utilisés pour enrichir les sols. De nos jours, les engrais chimiques sont adaptés aux carences des sols, afin d’augmenter la productivité des sols. Très souvent, l’azote, le potassium et le phosphore sont présents et combinés à d’autres éléments. La seule ressource de phosphore utilisée comme engrais est le minerai de phosphorite. Les dépôts de phosphorite sont rares et se retrouvent dans quelques régions géopolitiques. Personne ne peut …  Lire la suite

Les modifications de la vie amènent les changements de la base de la vie, le foyer. C'est ici que sont nés aujourd'hui les descendants qui vont demain contribuer pour une petite partie a l'agrandissement de la nation. Dans le foyer l'enfant reçoit son éducation et sa preparation pour la vie. C'est au foyer que les capacités dont il a héritées à sa naissance vont prendre racine et se développer. Les parents, base du foyer, reconnaissent le devoir qui leur incombe. Cela explique le développement et la presque mode, si j'ose dire, d'étudier l'enfant d'une manière profonde pour le comprendre et …  Lire la suite