McGill University Thèses et mémoires par auteur commençant par J

The rhythmic expression of an autoregulatory loop of circadian clock genes underlies the intrinsic circadian rhythmicity in the central circadian pacemaker of the suprachiasmatic nucleus (SCN). Clock genes are also known to be rhythmically expressed outside the SCN and outside the brain. While these peripheral circadian oscillators are functional, their expression is chiefly coordinated by the central circadian pacemaker of the SCN. This thesis presents the first evidence of a functional circadian oscillator in human peripheral blood mononuclear cells (PBMCs). Measuring levels of RNA transcripts in PBMCs sampled throughout specific behavioural protocols permitted the characterization of these peripheral circadian oscillators …  Lire la suite

The primary consequence of night shift work is a misalignment of the endogenous circadian pacemaker with the inverted sleep-wake cycle. This study evaluated the efficacy of a judicious schedule of light exposure on circadian adaptation to night work. Fifteen night shift workers (mean age +/-S.E.M.: 41.8 +/- 1.8 years) were studied for 3 weeks in their work environments under one of two experimental conditions. Treatment group participants underwent an intervention including bright light in the workplace, while control group participants were studied in their habitual light environments. The efficacy of the intervention was evaluated in the laboratory via constant routines. …  Lire la suite

Glucoamylase, a saccharifying enzyme, is applied in the brewing industry to hydrolyse the dextrins of malted barley into simple sugars which can then be fermented by brewer's yeast. In order to establish the potential of glucoamylase from Lactobacillus amylovorus for application in the brewing industry, the main objectives of this study were: (1) to determine the cultural conditions for growth and glucoamylase production, (2) to purify the enzyme to homogeneity using chromatography and electrophoretic techniques, (3) to study biochemical properties of the purified enzyme, and (4) to clone the gene coding for glucoamylase, and characterize the recombinant glucoamylase. The actively …  Lire la suite

Nutrient acquisition by Gram-negative bacteria requires strategies for passage across the outer membrane (OM). Because iron is a vital nutrient for bacteria, we aim to elucidate the molecular mechanism of its uptake. In an aerobic environment, ferric iron is predominant but exhibits low solubility. To overcome this challenge, bacteria import siderophores, ferric iron chelators. Siderophore import involves its binding to an OM receptor then to a periplasmic binding protein (PBP). Cytoplasmic membrane-embedded protein TonB, through its interaction with the periplasmic face of OM receptors, may provide energy to facilitate nutrient uptake. To explore the molecular mechanism of TonB-dependent transport, we …  Lire la suite

This study explores the effects of ethno-religious tensions on the dynamics of fraternalism in nineteenth-century Montreal. With the Irish "national society" as its focus, it relates the internal politics of the Saint Patrick's Society of Montreal to broader narratives of the cultural, intellectual and institutional evolution of civil society in Lower Canada. Beginning with an overview of sources and a discussion of early Irish migration, it proceeds to explore the effects of emerging social and political patterns and ethno-religious identities on a middle-class fraternal project from the early nineteenth-century to the dissolution of the Saint Patrick's Society in 1856.  Lire la suite

Microglia perform essential roles in the healthy brain to maintain homeostasis; however, in Alzheimer’s disease (AD), chronic activation of microglia due to the accumulation of amyloid-β (Aβ) peptides results in a toxic neuroinflammatory state that contributes to neuronal death. The 42-amino acid long Aβ 1-42 (Aβ42) peptide is a rapidly aggregating Aβ peptide that is highly toxic to neurons when it forms soluble oligomers. Aβ42-oligomer interacting peptide (AIP) has been shown to inhibit Aβ42 aggregation and neutralize Aβ42 toxicity in vitro at a 20:1 AIP:Aβ42 molar ratio, though it is unknown whether such a large molar excess of AIP is …  Lire la suite

This thesis examines public opinion towards the participation opinion of the British Auxiliary Legion in the Spanish Civil War. It is based on an analysis of British newspapers, periodicals and political discussion between 1835 and 1838. It suggests that, although there was some degree of support for the foreign policy of Lord Palmerston in sending the legion to aid liberalism in the Peninsula, yet that support declined rapidly. In spite of Palmerston's eventual claim that intervention in Spain had been worthwhile, public opinion was not to reflect the view that his policy had been a right one, or that the …  Lire la suite

The properties shared by neoplastic and embryonic cells have long been recognized and it has been postulated that both cell types may express a common set of molecules not found in adult tissues of the same histologic type. This study has utilized a rabbit antiserum raised against human fetal spleen to identify 'oncofetal' antigens of the human lymphoreticular system. One molecule found to have oncofetal properties was hemoglobin F (HbF). A radioimmunoassay was developed to measure the very low concentrations of HbF present in the adult circulation and an extensive clinical trial was undertaken to determine the possible value of …  Lire la suite

Postwar North America saw a fundamental change in the function, layout, and location of the parents' bedroom and bathroom in the typical middle-class home. This thesis argues that the representations of bedrooms and bathrooms in house plans published by the Central Mortgage and Housing Corporation (CMHC), in bathroom advertisements which appeared in women's magazines, trade periodicals, and architectural journals, and, in the 1959 film Pillow Talk, point to women's increased power in the immediate postwar years and constitute a foreshadowing of the Women's Liberation Movement of the 1960s. By revisiting the domestic landscape of postwar North America, this thesis provides …  Lire la suite

This paper will investigate issues that immigrants in Québec navigate when learning either French or English within the current educational infrastructure provided by the provincial government. In comparison to other provinces, Québec faces the least success with integrating allophones immigrants into the labour market. Québec is also currently managing massive shortages in various fields of work within the provincial economy. With immigration targets set by the Federal Government of Canada and Government of Québec, current educational infrastructure must be enhanced for allophones to be better accommodated and trained to join the work force. For this paper, information on Québec’s retention …  Lire la suite

Adams, Frank Dawson, 1859-1942 (Supervisor)  Lire la suite

The subject matter of this thesis comprises a geological study of the map area of Dungannon and Mayo townships in southeastern Ontario plus detailed studies of special features of the geology of the map area. [...]  Lire la suite

Climate modelling and high-latitude marine navigation require improved information on sea-ice floe extents and dynamics. New satellite sensors provide raw data of this nature but the volume of information makes human analysis impractical. To address this problem, a software system for automatic tracking of sea-ice floes in satellite imagery has been designed and evaluated. Using a recurrent neural network model, experiments were conducted to discover suitable design parameters. Simulated imagery time-sequences of increasing complexity were produced to train successive models. The networks produced were evaluated based on performance and reliability. A small-scale working system, able to map multiple input features …  Lire la suite

Phosphorous concentrations exceed water quality guidelines in most of the major rivers in southern Quebec. The problem is particularly acute in the Pike River, which drains into the Missisquoi Bay of Lake Champlain, in southeastern Quebec. Elevated phosphorus concentrations can lead to a reduction in the palatability of drinking water, a decrease in diversity of aquatic life and loss of recreational opportunities. All of these problems have been observed in the Bay. Two agricultural fields (the Marchand and Gagnon sites) located on the Pike River watershed, in southeastern Quebec were selected and equipped with instrumentation to measure and evaluate the …  Lire la suite

It is well known that the following factors have an important bearing on the conditions of the air when it reaches the working places;- 1. Air temperature at the surface. 2. Effect of adiabatic compression owing to increased depth. 3. Flow of heat from the earth's crust. 4. Heat given off by the oxidation of matter in the following processes: A. Oxidation of ore and timber. B. Oxidation of living tiaeue due to breathing of men and animals, C. Oxidation of materials due to mine fires and lamps. D. Oxidation. [...]  Lire la suite

L’échange et le transport de matière en rivières sont étudies en appliquant une nouvelle méthode expérimentale afin d'évaluer la structure d'écoulement tridimensionnelle des écoulements a surface libre. Le comportement dynamique et souvent turbulent de l'écoulement a surface libre est reconnu pour justifier les mécanismes de dispersion et de dépôt des matières dans l'environnement. L'influence des vitesses secondaires et des autres effets tridimensionnels de l'écoulement est encore mal connue. L'objectif de la présente recherche est de fournir des descriptions tridimensionnelles détaillées de la mécanique des fluides d'un écoulement de recirculation dans une baie rectangulaire adjacente à l'écoulement a surface libre. […]  Lire la suite

Hemmeon, J. C. (Joseph Clarence), 1879-1963 (Supervisor)  Lire la suite

The biochemist has been aided greatly in recent years in developing his knowledge of the metabolism of organic and inorganic substances in biological systems through the use of isotopes as tracers. Since the chemical properties of an element are determined solely by the number and distribution of electrons surrounding the nucleus, it is apparent that all isotopes of a given element should behave in an identical manner when participating in a chemical reaction. It is this fact which enables one to use separated isotopes to label a compound and to use it as a tracer in a chemical reaction or …  Lire la suite

Costopoulos, Andre (Supervisor1)  Lire la suite

Hydrogen, more than any other gaseous substance,has been investigated in electric discharges and a greatdeal of evidence has been accumulated for its existence inthe atomic state.  Lire la suite

This study examines the effects of maternal teaching style on the developing problem-solving abilities of deaf and hearing preschool children. Mothers and children from three matched groups, hearing mother-deaf child, hearing mother-hearing child, and deaf mother-deaf child, were videotaped while the mother taught the child to construct a small pyramid from 21 interlocking blocks and again when the child attempted the task independently. The tapes were coded and analyzed to examine maternal instructional style and subsequent independent child performance. The mothers in the deaf mother-deaf child and hearing mother-hearing child dyads used appropriate scaffolding behavior significantly more often than the …  Lire la suite

Kuhnlein, Harriet V. (Supervisor1)  Lire la suite

Brown, E. (Supervisors)  Lire la suite

The survival of the French Canadians as a distinct ethnic group in the midst of a much larger and more pervasive English-speaking society is, in many ways, usique in the history of race and culture contact. Numbering some 60,000 at the time of the British conquest of Canada in 1163, the French, by virtue of a high rate of natural increase, have grown to almost 3,000,000 in this country. The traditions and customs peculiar to French Canada center around the most cherished elements of its culture: the French language and the Catholic religion. These, in contrast to English Protestantism, are …  Lire la suite

This study is a comparative analysis of the marginalizarion of the Baha'is in Iran and the Ahmadis in Pakistan over the last forty years. It explores the relationship between Islam, the ulama and the state as explanatory variables. In particular, the increasing political influence of fundamentalist ulama and their closer association with state mechanisms, accompanied by the creation of a "purist," "Islamic" state ideology in Iran and Pakistan, leads to greater discrimination against these two heterodox Muslim minorities. The outcome is continuing institutionalized, state-sponsored discrimination that denies substantial legal, political and social rights to the Baha'is and the Ahmadis.  Lire la suite

Amabili, Marco (Internal/Cosupervisor2)  Lire la suite

The study of the biologica1 sciences has led to four great generalizations: 1. (A) Darwin's and Wallace's (100 years ago) theory of evolution by natural selection, which tells us that higher organisms are derived by a continuous evolutionary progression from the first primitive organisms. [...]  Lire la suite

The possible roles of the anti-apoptotic protein, Bcl-2, and pro-apoptotic Fas receptor-ligand interactions in cell death decisions during the development of B lymphocytes in mouse bone marrow and their maturation in the spleen have been evaluated in gene-modified and mutant mice. In Emu-bcl-2 transgenic mice, the population dynamics and tissue organisation of phenotypically defined precursor B cells, have been evaluated by immunofluorescence labeling, mitotic arrest, BrdU uptake, flow cytometry and in vivo radioimmunolabeling combined with light and electron microscope radioautography. In bone marrow of Emu-bcl-2 mice, the number and production rate of proliferating precursor B cells were increased. Immature B …  Lire la suite

Ward, Brian (Internal/Cosupervisor2)  Lire la suite

Keys, D. (Supervisors)  Lire la suite

Barbour, H. (Supervisors)  Lire la suite

While there is an overall decline in the incidence and mortality associated with stomach cancer in developed countries, the prevalence of gastric adenocarcinoma is still increasing in North America and Europe. Resection of the primary tumor is the most beneficial treatment; however, recurrence is seen in nearly a third of all patients that undergo curative intent surgery, primarily in the peritoneum. One proposed school of thought is that surgical trauma and post-operative infection lead to chronic inflammation, thereby providing a pro-tumorigenic environment for cancer spread. Lipopolysaccharide (LPS), an antigen present on the Gram-negative bacteria Escherichia coli, is a large proponent …  Lire la suite

Trade unionism in Canada as elsewhere, is essentially a phenomenon of modern industrial society, a reflex on the part of "the workers" to the action of capitalism in creating social strata in which the sole means of support is the daily wage. It is designed primarily to offset the unfairness and inequality of the labourer's bargaining position (1) in wage negotiations. History reveals no single genesis of it, or no uniform process of development through which all types of unionism go. [...]  Lire la suite

Although chemists often exploit the high stereo selectivity of hydrolytic enzymes to produce pure enantiomers, the difficulty in selecting the best hydrolase from hundreds of commercial hydrolases and microorganisms remains a major deterrent to their wider use. Moreover, the emerging ability to create large libraries of recombinant enzymes demands fast and simple selection methods. The current method of selection is time-consuming because it requires carrying out small-scale reactions and measuring enantiomeric purity. This thesis focuses on the development of methods to speed up this selection process. We first report the development of empirical substrate models for Aspergillus niger lipase (ANL) …  Lire la suite

Guo, Jin (Supervisor1)  Lire la suite

Reinhold, Caroline (Supervisor3)  Lire la suite

Martin, James G. (Supervisor1)  Lire la suite

Cell adhesion is essential to cell motility and tissue integrity and is regulated by the Integrin family of transmembrane receptors. Integrin binds to ligand extracellularly and provide anchor to the intracellular cytoskeleton via adhesion scaffolding proteins. In order to link cell to the surrounding matrix Integrin needs to be activated. Intracellular activation signals induce perturbations in Integrin cytoplasmic domain that are translated into a conformational change in extracellular region for high affinity ligand binding. Integrin engagement by matrix, in turn, triggers the assembly of adhesion complexes. Such early adhesions promote cytoskeletal organization with subsequent contractile activity that exerts forces against …  Lire la suite

This thesis describes an experimental investigation of semileptonic B meson decays with a D and pi mesons in the final state: B- → D+pi -e-nu e. The data for the analysis were collected with the CLEO II detector at the Cornell Electron-positron Storage Ring. The D meson is reconstructed in the D+ → K-pi+pi+ channel. The advantage of using this particular B decay mode is that there is no contribution from the D* due to phase space exclusion. This analysis is the first attempt at measuring non-resonant decays semileptonic decays with the CLEO II detector. Even though we do not …  Lire la suite

The concentration of extracellular ionized calcium (Ca2+ o) is the primary physiological regulator of parathyroid hormone (PTH) secretion. The parathyroid gland has a special ability to sense extracellular the calcium concentration and the mechanism whereby this is achieved became clearer when a parathyroid calcium-sensing receptor (CASR) was cloned and characterized. Inactivating mutations in the CASR gene have been identified as a cause of familial hypocalcemia hypercalcemia (FHH) and neonatal severe hyperparathyroidism (NSHPT). The goal of this thesis was genetic analysis of several families affected with FHH and NSHPT. Initially, we studied two families from Nova Scotia expressing both FHH and …  Lire la suite

Between February 1940 and June 1941, in four major deportations Soviet authorities moved Polish citizens to work-colonies in the Soviet interior and detained others in various prisons and camps. Based on war-time information, works on the deportations published in the West during the decades of communist rule in Eastern Europe and since reported figures of over 1.5 million deportees, of whom as many as half reportedly died in the USSR. These works held a prevailing view that Soviet intentions towards the deported Poles were genocidal. Recent work with Soviet archival materials has led Polish and Russian historians to revise the …  Lire la suite

The nutrient status of three Norway spruce (Picea abies L. Karst.) plantations in southwestern Quebec were studied through foliar analysis. At all locations low N and K and marginal Mg foliar concentrations were identified. Diagnostic fertilization resulted in significantly improved foliar K, N, Ca/K molar ratio and in some cases Mg. The foliage of the treated trees has an improved dark green colour as compared with the controls. From this research it is evident that nutrient deficiencies of N, and K in particular, are showing up in spruce stands in the areas where atmospheric pollution is relatively severe. The use …  Lire la suite

Radecka, Katarzyna (Supervisor2)  Lire la suite