McGill University Thèses et mémoires par auteur commençant par B

Determining the factors responsible for the origin and maintenance of diversity remains a difficult problem in evolutionary biology. There is extensive theoretical work which suggests that environmental heterogeneity plays a major role. This theory argues that diversification is ultimately due to divergent natural selection for alternative resources. In this thesis I investigate adaptation and the evolution of diversity in experimental populations of the asexual bacterium Pseudomonas fluorescens. In all experiments I introduce clonal isolates of Pseudomonas to a novel environment and allow evolution to occur through the substitution of random mutations. Adaptation can then be quantified by comparing evolved genotypes …  Lire la suite

Part I Prostate cancer treatment options have improved in recent years, but the disease remains prevalent in the elderly Canadian male population. Existing treatments for castration-resistant prostate cancer are inadequate and this necessitates innovation in treatment by drug co-administration or drug design. This century, and especially in the past decade, the concept of hybrid drug design has taken root in the literature. A series of hybrid compounds which combine key structural features of both androgen receptor antagonists and histone deacetylase inhibitors have been designed using the structure-activity relationship data available for each. Certain molecules are shown to inhibit the desired …  Lire la suite

Alcohol is frequently co-administered with other psychotropic substances, yet little is known about patterns of alcohol use in a simultaneous polysubstance context. In the present dissertation concomitant alcohol-drug administration is examined with an emphasis on delineating patterns of alcohol use when it is co-administered with psychostimulant drugs known to interact with neural mechanisms believed to be involved in mediating alcohol's ascending limb reinforcing effects: midbrain dopamine transmission. In two retrospective self-report studies polysubstance users reported on their simultaneous use of drugs and alcohol. Results revealed that alcohol was commonly co-administered with various abused substances, particularly with psychostimulant drugs that are …  Lire la suite

Carli, Franco (Internal/Cosupervisor2)  Lire la suite

The present experiment was conducted to explore the time-course of lexical ambiguity resolution in normal control (NC) subjects and the nature of right hemisphere-damaged (RHD) and left hemisphere-damaged (LHD) patients' impairments in this process. NC, RHD and LHD subjects performed a cross-modal lexical decision task, in which they heard sentence contexts that were biased toward the dominant or subordinate meanings of ambiguous words occurring before the end of the sentence. Written target words related to the dominant or subordinate meaning of the ambiguous words were introduced either at the onset of the ambiguous word (immediate condition), or 1000 ms later …  Lire la suite

Boivin, Guy (Supervisor1)  Lire la suite

RésuméLa représentation sociale du deuil après suicide au Québec évolue au fil des époques et s’actualise encore aujourd’hui. De plus en plus, les personnes endeuillées à la suite du suicide d’un·e proche participent elles-mêmes à sa co-construction. Mais une place y est-elle aménagée pour la consolation, dont la fonction est d’atténuer les souffrances physiques, psychologiques et morales éprouvées en contexte de deuil ? C’est la question à laquelle ce mémoire vise à répondre. Dans un premier temps, la consolation est définie. Négligée pendant plusieurs décennies, elle n’apparaît cependant que de façon non-systématique et détournée dans le discours contemporain sur le …  Lire la suite

The diversity and community composition of birds and seven insect taxa: butterflies and skippers (Lepidoptera); Carabidae (Coleoptera); Dolichopodidae, Syrphidae, Sphaeroceridae, Chloropidae (Diptera); Apoidea (Hymenoptera) were studied in old field habitats surrounded by different intensities of urbanization in the Montreal region. A total of 386 breeding birds of 42 species as well as 2255 migrating birds of 31 species were surveyed. More than 7000 insect specimens of 264 species were identified. Results indicate that, in terms of studied taxa, old field biodiversity remains fairly constant despite different surrounding land use. The exceptions were that butterfly and skipper species richness and number …  Lire la suite

Mannoproteins from Saccharomyces cerevisiae (Baker's yeast) were extracted in high yield. The crude extract was resolved into two components, $ alpha$ and $ beta$, using capillary electrophoresis. These were both shown to be fragments from the cell wall mannoproteins. The $ alpha$ component consisted mainly of the protein portion of the mannoproteins and the $ beta$ component consisted of the long highly phosphorylated mannan chains. Fragmentation occurred when the covalent bonds between the mannans and the asparagine residues were hydrolysed during the hot citrate extraction procedure. The $ alpha$ component was identified as the active emulsifying agent. Although the $ …  Lire la suite

Boutin, Maurice (Supervisor)  Lire la suite

High output of prostaglandins (PGs) are the hallmark of inflammatory and immune reactions. A rate-limiting step in the production of PGs is the presence of the enzyme cyclooxygenase (COX). COX exists as two isoforms: COX-1 which is constitutively expressed in most cells and COX-2 which is inducible by LPS, proinflammatory cytokines and other stimuli in cells involved in inflammation. The objective of this study was to determine the effect of nonsteroidal antiinflammatory drugs and proinflammatory cytokines on COX-2 expression in human macrophages. COX-2 specific (NS-398) and non-specific (aspirin, indomethacin and naproxen) inhibitors showed no effect on COX mRNA and protein …  Lire la suite

The space industry has been using cyanate ester resins and autoclave processing for over 20 years to produce structures that can withstand the extreme conditions during launch and operation in space. An effort is now being made to reduce costs by implementing Out-of-Autoclave (OoA) Vacuum Bag Only (VBO) with epoxy resins. However, without knowledge and understanding of different material systems, material selection can be a very risky and costly process. The first objective of this thesis work is to develop a streamlined characterization-based methodology to select composite systems for structural space applications. Seven materials are characterized by performing thermogravimetric analysis …  Lire la suite

Following and at times reworking the relation between language, society and selfhood in the antifoundationalist philosophies of Charles Taylor and Richard Rorty, the thesis develops the idea of the novel as a kind of conversation. The thesis takes James Joyce's Ulysses as a progression of thought and style in which its three principal characters, Stephen Dedalus, Leopold Bloom and Molly Bloom, expound their views and then lapse into silence as part of an ongoing conversation. Three episodic conversations in particular are discussed: for Stephen, Scylla and Charybdis; for Bloom, Cyclops; and for Molly, Penelope. These conversations, it is suggested, parallel …  Lire la suite

Gryllus bimaculatus de Geer is one of the most widely distributed species of field crickets and ranges from South Africa, the Mediterranean basin, Southern Asia and the East Indies to Japan. (Cousin, 1956, 1961). Chopard (1938) found that this species does not range north of the northern shore of the Mediterranean. Cousin (1941) was the first to recognize the significance of a regular phenomenon in the variation of pigmentation of G. bimaculatus specimens reared in the laboratory from collections made in the field in southern France.  Lire la suite

This thesis attempts to analyse both the characteristics and the presuppositions that constitute the writing of the philosopher and literary critic, Jacques Derrida. More concretely, this analysis proposes to bring out the principal factors that illustrate the form of writing and thought in Glas. Glas is a real laboratory where Derrida plays with the "text" and the broken form of thought. Derrida proves that the broken form of writing can neither achieve the status of oeuvre nor protect its own literary nature.  Lire la suite

The author describes meditative practice in some of its historical and cultural contexts. She then reviews the literature and research on meditation pertinent to attention, the brain, stress, spirituality and personal development. She discusses the implications of meditation research for education. Finally, she presents suggestions and comments concerning the feasibility of implementing meditation in the schools.  Lire la suite

Gregory-Eaves, Irene (Internal/Supervisor)  Lire la suite

The dynamic wedge is created by moving one of the primary beam limiting collimators in a continuous fashion to create a continuously decreasing field width while the radiation beam is on. Because of this collimator motion, different segments of the treatment field will be exposed to the primary beam for different intervals of time. This process of shrinking the field width while modulating the collimator jaw velocity and dose rate creates the desired wedge-shaped isodose gradient across the treatment field. The amount of dose that is delivered to the patient as the collimator moves across the treatment field is controlled …  Lire la suite

The Hepatitis C Virus (HCV) is a major public health concern considering it infects around 3% of the global population and there is currently no virus-specific therapy or vaccine. Several virally-encoded proteins have been identified as potential targets for inhibitor design including the helicase-containing nonstructural protein three (NS3). Helicases are enzymes that are responsible for the separation of double-stranded nucleic acids prior to most processes of nucleic acid metabolism. It is well documented that disabling the HCV helicase through mutation results in the arrest of the viral lifecycle. The aim of our work was to characterize the details of the …  Lire la suite

The term “rearrangement” refers to an irreversible reaction which produces a change in the structural arrangement of a molecule, “Essentially the processes of rearrangement are basically in every case accompanied by intramolecular oxidation and reduction. This oxidation reduction mechanism involves electron transfers within the molecule and consequently is best explained on the basis of an electronic mechanism. This concept was first advanced by Jones and later expressed by Stieglitz , Robinson and Ingold.” Molecular transformations are relatively rare because simple adjustments that can occur within a single molecule have usually been accomplished in the process of synthesis. However, molecules may, …  Lire la suite

In this thesis based on survey methodology, a questionnaire was distributed to 36 parents who were raising a child with a developmental disability. Parents were asked about their views on social sexual skills development during the formative years, their satisfaction with available social sexual services and the importance they attached to these services. A parent group interview was conducted to enhance understanding of this area. Findings indicated that parents do support social sexual skill development for their children and teens. Parents also indicated that it was important for parents to have access to relevant social sexual services.  Lire la suite

This thesis investigates the nature and distribution of ground ice occurrences on the central Fosheim Peninsula, Ellesmere Island, and assesses the potential for thermokarst in light of possible climatic warming. Field observations conducted in 1990 and 1991 involved geomorphological and cryostratigraphic examinations of twenty-eight ground ice sections exposed in retrogressive thaw slumps and ground probing radar surveys of two of the thaw slumps. Samples were taken of ground ice and sediments exposed in thaw slump headwalls for laboratory analysis. Samples were analyzed for moisture content, grain size distribution, and Atterberg limits. Gravimetric ice contents were calculated and an average ice …  Lire la suite

The Bishop of Norwich was descended from the baronial Despenser family. The name was originally Despenser or le Despenser, but in his case the contracted form of Spencer or le Spenser was often used. The origin of the name goes back to the Latin word dispensator, which is defined as a man who spends, accepts, compensates and impends or weighs out. It means one who administrates money or handles loans and debts for another man, for example the despenser of the public money of the state of Carthage. A despenser was a servant who corresponded to the maitre du palais, …  Lire la suite

A classification of airflow pattern types is formulated for the region on the basis of synoptic weather maps for November, 1956 to March, 1958. Regional indices of the zonal and meridional flow at mean sea level and the 500 mb level are examined in relation to the airflow types. The spatial and temporal variations of weather phenomena associated with the types are analyzed by quantitative weather parameters and the significance of the results is assessed with reference to local weather forecasting and palaeoclimatic reconstructions.  Lire la suite

Artistic appropriation constitutes a technique that has been widely used by artists for centuries. It seems to have transcended most artistic movements. Appropriation consists of reproducing a pre-existing work, or of being inspired by it, in order to create a new and distinct work of art. Appropriation poses several problems for copyright law because it challenges the basic principle of copyright which provides that a substantial reproduction of a work without the authorisation of the copyright owner amounts to an infringement. Unlike the United States where it was held that an appropriationist work infringed the copyright of a photographer, the …  Lire la suite

The elucidation of the structure of polysaccharides synthesized by bacteria has been shown to have both practical and theoretical importance. A knowledge of the polysaccharides formed by pathogenic bacteria has been found to be of great benefit in that branch of medical science known as immunology. The work reported here is part of a general investigation of the polysaccharides synthesized by certain bacteria, undertaken for the purpose of gaining information regarding the nature and chemical interrelation of substances capable of utilization in the plant for the synthesis of polysaccharides. [...]  Lire la suite

That all elements which are part of living organisms must be present in their environment, if they shall be in a position to propogate, is axiomatic. However the form in which these elements are useful for the building of cells, differs widely for various organisms. [...]  Lire la suite

La théorie des systèmes dynamiques était recherchée par des scientifiques et des mathématiciens au cours des derniers siècles. Aussi, l’entropie de Shannon et Gibbs, qui était introduit en premierpar Claude Shannon dans son célèbre papier de 1948 [1], a commencé une ère de la recherche des systèmes dynamiques, et, sans doute, était la source de la théorie de l’information. Dans ce thèse, on commence avec une introduction assez complète de la théorie des systèmes dynamiques dans la guise de la théorie de la mesure. On continue avec la d éfinition de l’entropie de Shannonet Gibbs, et nous montrons quelques théorèmes …  Lire la suite

Hinsberg, Vincent Johan van (Internal/Cosupervisor2)  Lire la suite

This thesis is a description of the process of constructing a productive Other for the purpose of being admitted into Canada as a Convention refugee. The manuscript is divided into two parts: in Part One, The Claimant, the process of claiming refugee status is analyzed with respect to two actual cases which were transcribed in Montreal in 1987, and contextualized by reference to the laws and jurisprudence that underlie it. In Part Two, The Other, I re-examine the entire process with reference to methodologies from the realm of discourse analysis and interaction theory, paying special attention to the works of …  Lire la suite

Severe D-1 directional Fourier truncation of the equations for D-dimensional (D = 2, 3) incompressible flow leads to a small number of coupled PDE's in one space dimension with the same inviscid quadratic invariants as the original set. Numerically generated equilibria for inviscid truncated versions of the reduced systems agree with predicted energy-enstrophy (D = 2) and energy (D = 3) equipartition spectra based on statistical mechanical equilibrium. Viscous calculations for forced and decaying turbulence at high Reynolds number are consistent with k$ sp{-5/3}$ inverse energy and k$ sp{-3}$ direct enstrophy cascading inertial ranges in two dimensions and with a …  Lire la suite

Kakkar, A. K. (Supervisor)  Lire la suite

Cardiometabolic and psychiatric disorders frequently occur in the same patient, and an important shared risk factor among them is exposure to early life adversity (ELA). Nevertheless, the specific biological mechanisms connecting ELA to the co-occurrence of cardiometabolic and psychiatric conditions are not yet understood. In fact, not all individuals exposed to ELA will develop deleterious consequences of this exposure, suggesting an individual variability on the susceptibility to ELA effects. Dopamine (DA) neurotransmission is responsive to ELA and plays a role in shaping the development of these two categories of disorders. Here we demonstrated that individual genetic variations associated with dopaminergic …  Lire la suite

Seed-hairs are fibers located on the seeds of various plants, designed by nature to make it possible for the seeds to spread by the wind. One of these seed fibers, cotton, is exceptional in its high content of cellulose and has attained an importance far exceeding that of any other material of its kind. Other sources include kapok, tree cotton, cat-tail floss, milkweed floss and cotton grass. Kapok is a seed fiber, cultivated in the East Indies and is commonly used for upholstery and lifebelts. None of the others have shown much commercial importance.  Lire la suite

This project takes the idea of the "twilight zone" as a central organizing principle to examine ambiguous public and private spaces in popular representations of gender, the home, and the family in the postwar period. I argue that the intimate address of new media technologies—movies and radio, in their own ways, as well as television—creates an uncanny virtual space between the public sphere of commerce and entertainment and the private sphere of the home, reflecting a larger experience of social and spatial liminality for women. Through close readings of the science-fiction anthology TV program The Twilight Zone (1959-1964) and other …  Lire la suite

Polyphenol oxidases are important enzymes because of their role in food spoilage, oxidizing monophenols into o-diphenols and/or diphenols into the corresponding o-quinones. The resulting compounds are unstable and can rapidly form brown colored compounds, called melanins. Polyphenol oxidases, (PPOs) have been purified from several sources, particularly from fruits and vegetables. However, successful purification of PPO to homogeneity from plant sources has always been difficult. The purification procedure of PPOs from cassava tuber consisted of (1) the preparation of cassava acetone powder; (2) the buffer extraction of the acetone powder to obtain a crude extract, followed by one of two possible …  Lire la suite

Cette thèse est composée de trois études empiriques qui examinent des sujets reliés à la santé, l'assurance santé, et la politique de santé. Le premier chapitre évalue les effets du partage des coûts des médicaments prescrits sur l'utilisation des soins de santé primaires et sur les hospitalisations évitables. Cette étude utilise une variation exogène dans le partage des coûts des médicaments qui a été introduit par le « Medicare Modernization Act » pour évaluer les effets croisés des prix sur l'utilisation des services complémentaires, et les effets associés de compensation sur la santé. Le deuxième chapitre examine plus en détail …  Lire la suite

Un test de dénomination auditive composé de sons nonverbaux significatifs et un test de dénomination visuelle composé d'images correspondant aux sons, furent présentés aux ll8 enfants la âgés entre 3-1/2 et 16 ans. L'habilité de nommer les sons nonverbaux se développe rapidement jusqu' à l'âge de 8 ans avec seulment une légère améloriation après cet âge. [...]  Lire la suite