McGill University Thèses et mémoires par auteur commençant par B

Anthelmintic treatment of livestock is an important aspect of the control of gastrointestinal parasites. Resistance to anthelmintics is common, and an understanding of resistance requires knowledge of an anthelmintic's mode(s) of action and mechanism(s) of resistance. The parasitic nematode, Haemonchus contortus, has developed resistance to benzimidazoles and avermectins/milbemycins. Proposed mechanisms of resistance are here supported by genetic changes observed in genes whose protein products are believed to interact with these anthelmintics. Statistically significant differences in allele frequencies were observed between untreated and ivermectin- and moxidectin-treated strains in a gene encoding a putative glutamate-gated chloride channel alpha subunit, a proposed target …  Lire la suite

Cette étude examine la relation entre les stratégies d'adaptation, l'identité culturelle et la consommation de drogues et d'alcool chez les jeunes des Premières Nations. Quatre-vingt sept étudiants provenant de deux écoles dans deux communautés distinctes des Premières Nations au Québec, Canada ont participé à cette étude. Les résultats démontrent que l'adoption de comportements ethniques, une composante de l'identité culturelle, peut protéger contre la consommation de drogues et d'alcool. D'autre part, les participants qui s' identifient à la culture blanche et qui utilisent le désengagement comportemental comme stratégie d'adaptation sont les plus susceptibles à consommer ces stupéfiants. Les résultats de cette …  Lire la suite

RésuméL'identitée culturelle est considérée comme étant un facteur qui promouvoit la résilience individuelle et culturelle chez les jeunes autochtones. Le climat scolaire semble avoir un effet protecteur interculturel contre l'intimidation et la victimisation. L'examen du lien entre l'identité culturelle et l'intimidation permet une compréhension plus nuancée des dimensions de l'identité culturelle impliquées dans la protection des jeunes autochtones contre les comportements d'intimidation. Soixante neuf étudiants vivant à Kawawachikamach, une réserve des Premières Nations au Québec, Canada ont complétés des auto-évaluations portant sur leur l'identitée culturelle, leur perception du climat scolaire et la fréquence dans laquelle ils ont étés intimidés ou …  Lire la suite

Platt, Robert William (Supervisor2)  Lire la suite

It is generally believed that the orienting reaction, the first response of an organism to a novel or unexpected stimulus, tends to facilitate sensory, central and response processes. Pavlov (1927) suggested that "the orienting reflex tunes the correspondins analyser to ensure optimal conditions for perception of the stimulus." More recently, Lacey (1959) has stated that an increase in skin conductance, a characteristic component of the orienting reaction, "facilitates transaction of the organism with the environment." As far as sensory and perceptual processes are concerned, there is considerable evidence for a facilitatory effect of the orienting reaction. For example, Martin and …  Lire la suite

The theory of Specific Heat has two very distinct parts to its development. These are a) the Classical Theory, b) the Quantum Theory. The Quantum theory was first applied by Einstein in 1907 and it was in this paper (1) that Einstein solved the fundamental problem of the subject. Einstein replaced the classical mean energy for a linear oscillator by an expression derived using Planck's hypothesis as to the quantal relationship between energy and frequency. Since the specific heat is defined as being the derivative of the energy with respect to temperature, it was a simple matter, once having an …  Lire la suite

Cette étude examine l'effet du système d'écoles résidentielles sur les Cris et leurs communautés. Les quatre questions directrices pour l'étude furent:(i) Comment les séquelles du système d'écoles résidentielles affectèrent la vie des survivants dans des communautés cris? (ii) Comment l'expérience des écoles résidentielles continue-t-elle de faire un impact sur le tissue social et culturel des communautés cris de Mistissini, Oujé-Bougoumou et Waswanipi? (iii) Quelles leçons pouvons-nous collectivement tirer des histoires de ces survivants qui encourageront la guérison et permettront aux générations futures d'avancer dans des directions positives? (iv) Quel est le rôle de l'éducation dans ce processus et quels savoirs …  Lire la suite

The primary hypothesis of this research was that improved cowpea genotypes (selected under sole crop) could yield well in several Nigerian cropping systems, and that there were cowpea characteristics that improved overall system productivity. Cowpea lines were identified which were high yielding and stable in several management systems. Practices such as not applying insecticide and intercropping both reduced cowpea grain yield significantly. Land equivalent ratios were greater than one for all tested intercrop systems: cassava-cowpea (1.21-2.35), maize-cowpea (1.31-4.23), maize-cassava-cowpea (1.63-3.40) and millet-cowpea (1.13-6.88). Nitrogen nutrition of component crops was investigated. Line influenced both maize grain (12.5-28.4 kg ha-1) and total …  Lire la suite

With the exception of the inert gases, the gaseous elements do not exist in the atomic state at ordinary temperatures. They combine with themselves to form stable molecules which will dissociate only at elevated temperatures. However, there are many chemical processes which involve these materials and which indicate that, at some time during the reaction, they exist as atoms.  Lire la suite

In the first stage of the present investigation, the 2-amino-4-(x-pyridyl)-thiazole and 2-amino-4-(y-quinolyl)- thiazoles were synthesized. Various methods were investigated. The best method, giving the highest yields and the purest product, was found to be that in which the appropriate acetylpyridine and acetylquinoline hydrobromides were condensed with thiourea in polar solvents.  Lire la suite

Une fois activées par leur peptide antigénique, les cellules T entreprennent la réplication de leur ADN, effectuent la division cellulaire et se différentient en des lignées spécifiques aux pathogènes. Tous ces processus requièrent un effort coordonné afin de coupler la transduction du signal à la disponibilité des nutriments, de telle sorte que les cellules puissent répondre à leurs besoins métaboliques accrus. La transition de la forme T naïve, un état caractérisé par la quiescence et une activité catabolique, à la forme T active, un état de biosynthèse et d’activité anabolique, est un exemple important de reprogrammation métabolique. Un phénomène majeur …  Lire la suite

Clopidogrel is an antiplatelet drug prescribed to prevent stent thrombosis after a percutaneous coronary intervention (PCI). Previous evidence suggests that some widely prescribed statins may inhibit the antiplatelet effects of clopidogrel via competitive metabolism of its activating enzyme cytochrome P450 3A4 (CYP3A4). The objective was to investigate the possibility of an interaction post-PCI between statins and clopidogrel. We carried out a population-based cohort study identifying 10,491 patients using clopidogrel post-PCI (2001-2004). The outcome was a composite of death of any cause, myocardial infarction, unstable angina, repeat revascularization, and cerebrovascular events. We found that co-prescription of CYP3A4-metabolized statins (hazard ratio (HR) …  Lire la suite

Since Atkinson (1699), who was the first cytologist to investigate the andromeiosis of Trillium, the species of this Asiatico-American genus have been largely used by cytogeneticists. The large dimensions of their chromosomes (“average 30 microns in length by three microns in width in somatic divisions” Warmke, 1941, 1937) and their low number (the basic haploid number is 5) were good features for the study of mitosis and meiosis mechanisms and chromosomes structure. Due to technical facilities, the root tip cells and androsporogenetic tissue were the basic material mainly employed; the gynohaplogenesis and the embryology were almost neglected though it was …  Lire la suite

Chan, Laurie (Supervisor)  Lire la suite

The hemagglutinin glycoprotein (HA) encoded by measles virus (MV) is a type II integral membrane protein that is expressed at the infected cell surface. The maturation of HA was studied in infected Vero cells. HA oligomerized into a disulfide-linked homodimer with a t$ sb{1/2}$ of 30 min. The rate of transport of HA to the medial Golgi complex was also examined using endoglycosidase-H and found to occur with a t$ sb{1/2}$ of 2 hr. Genes encoding two mutant HA proteins shortened at their C-terminal end by either 18 (HA$ Delta$18) or 223 (HA$ Delta$223) amino acids were constructed and studied …  Lire la suite

From the association of the epsilon4 allele of apolipoprotein (apo) E with Alzheimer's disease (AD) to the more recent reports of reduced risks of developing the disease when taking cholesterol lowering agents, links seem to point for a central role for lipoprotein metabolism in the AD brain. While the association with apoE4 is the strongest and most reproduced risk factor for AD, roles for other proteins involved in lipoprotein metabolism in the periphery have not been thoroughly investigated. Using the entorhinal cortex lesion (ECL) paradigm in human apoE-targeted replacement mice we examine whether apoE4 has effects on reactive synaptogenesis in …  Lire la suite

Salin, Eric D. (Supervisor)  Lire la suite

Nave, Jean-Christophe (Internal/Supervisor)  Lire la suite

The Canadian Shield is classified as a dormant igneous formation that has been proposed as a suitable location for the construction of a deep geologic repository for the disposal of heat-emitting spent nuclear fuel. The permeability characteristic of its intact granite is therefore of great importance to establish its effectiveness towards attenuating the migration of radionuclides. These can be released either from the natural breakdown of the metallic containers housing the waste or due to an accidental leak being generated by rock movements associated with the temperature rise in the repository location. This research investigates the bulk permeability of granite …  Lire la suite

The protean findings on patients with adrenocortical tumors and the fact that the adrenal cortex is requisite to life has long been established. Tilesius, in 1803, described obesity, precocious breast development and hirsutism in a girl of four, found to have a tumor of the adrenal cortex. [...]  Lire la suite

The support of local communities has become accepted as critical for success in wildlife conservation, particularly in developing areas such as Kenya. Human-wildlife conflict is a major cost to people living amongst wildlife, and a threat to support for conservation. This research focused on conflict experienced by Maasai pastoralists in Laikipia, Kenya, an area of conservation importance and the site of many community conservation initiatives. It was found that the levels of conflict experienced by the communities were much higher than suggested by official reports from the Kenya Wildlife Service. Livestock depredation, mainly by hyenas, was identified as particularly underrepresented. …  Lire la suite

Contexte: Le manque de recherche sur le rôle déterminant des quartiers urbains sur la santé mentale—surtout dans un contexte Canadien—a motivé notre étude des effets des environnements urbains sur la dépression et de la détresse au Canada. Objectif: Le premier manuscrit de cette mémoire s’agit d’une revue systématique de la littérature qui vise à élucider les mécanismes par lesquels les quartiers influencent la santé mentale des adultes. Le second manuscrit, une deuxième revue systématique, vise à résumer les effets de la transformation des quartiers urbains sur le bien-être psychologique des résidents. Le troisième manuscrit teste l'hypothèse que le changement socioéconomique …  Lire la suite

Notre étude visait à comprendre les patrons spatiaux de diversité gouvernant la répartition d'une famille de mouches qui domine le Nord, les Scathophagidae (Diptera), dans le Canada septentrional. Nous avons également examiné les changements à long terme survenus dans la taille de Scathophaga furcata, une espèce répandue et commune, sur une échelle temporelle d'un demi-siècle. Les données contemporaines composées de 2320 Scathophagidae ont été obtenues lors de récoltes effectuées en 2011 et 2012 dans le cadre du Programme sur la biodiversité nordique. Les spécimens historiques on été recueillis lors d'un inventaire des insectes du Nord canadien, le Northern Insect Survey, …  Lire la suite

The use of light steel gauge framed walls in the residential and commercial sector is increasing in popularity. However, our knowledge of the performance and the behaviour of structures using such walls when subjected to lateral wind and seismic loads is limited. At present, no design method for light gauge steel shear walls is contained in Canadian codes or standards. For this reason a research project on steel frame/wood panel shear walls was undertaken. A comprehensive database of monotonic and reversed cyclic tests on steel frame/wood panel shear walls is needed to obtain different wall parameters for use in design. …  Lire la suite

Troubadour style painting first appeared at the Paris Salon in the opening years of the Nineteenth century. After its initial success during the reign of Napoleon, it continued to fiourish in the period of the Bourbon Restoration. Of small scale and primarily devoted to the representation of anecdotal scenes from the lives of the great French monarchs of the Middle Ages and the Renaissance periods, troubadour style painting evoked nationalist and patriotic sentiments. This analysis of its socio-political foundations in the Napoleonic period reveals an implicit royalist message, particularly in the works of Pierre Revoil and Fleury Richard, the two …  Lire la suite

Cette étude porte sur le comportement du chlorure d'or (III) en solution acide contenant du sulfate de fer (III) et de l'arsenic (V) sous forme de solutés soumis à des traitements de neutralisation ou bien de type hydrothermique. En particulier, le champ d'application de la recherche liée à cette étude s'étend au comportement de co-précipitation du chlorure d'or (III) avec des précipités de fer (III) – arsenic (V) qui se forment soit par oxidation sous pression et/ou dans des autoclaves de lixiviation, soit lors de la neutralisation de solutions récupérées après oxidation sous pression/lixiviation. Les résultats de cette étude indiquent …  Lire la suite

Modern aircraft design involves a large number of design parameters from a multitude of disciplines. Obtaining high-fidelity solutions for all combinations of such parameters is computationally unfeasible. Although the solution to a large-scale system of equations is generally an element of a large-dimensional space, the solution may actually lie on a reduced-order subspace induced by parameter variation. In order to capture this subspace, samples of the high-dimensional system called snapshots are used to build a reduced-order model. These models have generated interest as a means to compute high-fidelity solutions at a much lower computational cost. However, little value can be …  Lire la suite

The Common Substring in Random Strings (CSRS) problem is defined as follows: what is the probability that a set of r random strings of length n generated by a random process P contain a common substring of length k? In this thesis, we investigate the CSRS problem and introduce two new methods for computing approximate solutions to the CSRS problem in the cases where the random strings are generated by a Bernoulli or Markov process. We also present generalizations to the methods to compute the probability of finding a common substring among only q of the r random strings, and …  Lire la suite

Les métaux peuvent être utilisés comme vecteurs énergétiques et sources de combustibles de substitution aux hydrocarbures et aux combustibles fossiles en raison de leur abondance et de leur densité énergétique comparable, ce qui les rend applicables aux cycles de production industrielle d'électricité à grande échelle. La connaissance de la dépendance de la vitesse de la flamme par rapport à la température initiale du mélange est importante pour la compréhension du rôle du transfert de chaleur par radiation et des mécanismes de stabilisation des flammes. Un nouveau brûleur de poudre métallique à contre-courant permet de mesurer la vitesse de flamme dans …  Lire la suite

The research presented in this thesis deals with the problem of range image registration for the purpose of building surface models of three-dimensional objects. The registration task consists of finding the translation and rotation parameters which properly align overlapping views of the surface so as to reconstruct from these partial surfaces, the complete surface representation of the object. The approach taken is to express the registration task as an optimization problem. We define a function which measures the quality of the alignment between the partial surfaces contained in two range images. The function computes a sum of Euclidean distances between …  Lire la suite

Three direct interfaces for coupling high performance liquid chromatography (HPLC) with atomic absorption spectrometry (AAS) were developed and optimized for the determination of ionic organolead, organoselenium and organoarsenic compounds. The first all-quartz interface consisted of a thermospray nebulizer and a flame microatomizer in which ionic alkyllead analytes (R$ sb{ rm n}$Pb$ sp{ rm (4-n)+};$ R = CH$ sb3,$ C$ sb2$H$ sb5)$ were atomized by a methanol (from HPLC eluent)-oxygen kinetic flame, and channeled in a quartz tube (atom keeper) mounted into the AAS optical beam. Alternately, the classical electrothermal atomization technique for organolead species (quartz furnace under hydrogen atmosphere) was …  Lire la suite

Kalff, Jaap (Supervisor)  Lire la suite

Suissa, Samy (Supervisor)  Lire la suite

Verb-particle constructions (phrasal verbs) are a notoriously difficult aspect of English to acquire for second-language (L2) learners, especially for those whose L1 lacks verb-particles. The present study was conducted to assess whether L2 English speakers would show sensitivity to the subtle semantic properties of these constructions, namely the gradations in semantic transparency of different verb-particle constructions (e.g., finish up vs. chew out). L1 French, L2 English bilingual participants completed an off-line (explicit) survey of similarity ratings, as well as an on-line (implicit) masked priming task. In their off-line responses, bilinguals' ratings of the similarity between verbs (e.g., look) and verb-particle …  Lire la suite

In the 18th century, drama slowly broke away from its courtly tradition and found an increasing echo in Paris and other regions of France. With the broadening of its audience came a growing interest in drama itself. The unprecedented production of writings about the world of theatre, such as the memoirs written by its community, which are often overlooked by literary critics, can serve as evidence of this phenomenon. At least two motives can be isolated from the meta-discourse (discourse about discourse) found in these memoirs: (1) to defend the reputation of drama as a practice, which at the time …  Lire la suite

A theoretical and experimental study of the spatial spread of electron dose distributions for pencil and broad electron beams in various media is presented. We discuss in detail two methods for measurement of electron beam kinetic energies, describe our technique for the measurement of the optical density versus dose relationship for radiographic films, and present the experimental set-up for the measurement of the spatial spread of electron dose distributions for pencil and broad electron beams. The Fermi-Eyges theory for the small angle multiple Coulomb scattering describes the spatial electron distribution in scattering media. The spatial spread of a pencil electron …  Lire la suite