No description available.

No description available.

No description available.

No description available.

The experiment was designed to study the effect of conditionality on the growth and decline of expectancy scores during acquisition and extinction The results revealed that conditionality affects the growth of expectation during acquisition for both direct and vicarious tasks but has no effect on variation scores, Percentage of reinforcement is also effective, the expectancy scores for the 100% reward groups rising to a higher level in acquisition and dropping off more rapidly in extinction than for the 50% reward groups. Problems arising from the differential effect of conditionality on expectancy scores and variation indices, and from differential expectancy levels at the end of acquisition were discussed. / Thesis / Master of Arts (MA)

Electromagnetic and heat transfer analysis is used to determine possibility of selective heating of nanometer-sized, metallic catalyst particles attached to a ceramic support through microwave irradiation. This analysis is incorporated into a macroscopic heat transfer model of a packed and fluidized catalyst bed heated by a microwave field to predict thermal effects associated with selective heating of the catalyst sites. The model shows a dependence on particle size and microwave frequency on the selective heating of the catalyst sites. The macroscopic thermal effects are shown to be small for a typical experiment. However, changing the support material and catalyst particle size are shown to distinguish the thermal effects associated with selective heating of the metallic catalysts. / Master of Science

Atherosclerosis is a disease characterized by cholesterol-rich plaques within the intima of medium and large arteries. Cholesterol deposition is thought to occur by infiltration of low-density lipoprotein (LDL) into lesions followed by uptake into macrophages, generating lipid-loaded “foam cells.” Foam cells can also be generated in vitro by treatment of macrophages with LDL or oxidized LDL (oxLDL). The purpose of the current investigation was to determine the contribution of selective cholesteryl ester (CE) uptake versus whole-particle uptake during LDL-induced foam cell formation in cultured macrophages. Murine bone marrow-derived macrophages (BMMs) exhibited significant cholesterol accumulation when treated with LDL as indicated by quantification of cellular cholesterol and visualization of Oil Red-O-stained neutral lipid droplets. Uptake of LDL cholesterol was determined by measuring uptake of 3H and 125I into BMMs during treatment with [3H]CE/125I-LDL. [3H]CE uptake was linearly related to the LDL concentration at the concentrations used and was much larger than 125I uptake, indicating that the majority of LDL-cholesterol was acquired by nonsaturable, selective CE uptake. This pathway was demonstrated to be independent of whole-particle uptake by showing that inhibition of actin polymerization blocked LDL particle uptake but not selective CE uptake. Analysis by thin-layer chromatography (TLC) indicated that following uptake, [3H]CE was rapidly hydrolyzed into [3H]cholesterol by cells and largely effluxed into the culture medium. In contrast to LDL, studies of [3H]CE/125I-oxLDL uptake demonstrated that CE was acquired from oxLDL by whole-particle uptake with little or no selective CE uptake. Using a series of ten different [3H]CE/125I-oxLDLs oxidized for 0-24 hours, selective [3H]CE uptake was shown to be progressively impaired by LDL oxidation, while 125I-LDL particle uptake was increased as expected. Interestingly, the impairment of selective CE uptake occurred very early in LDL oxidation and this minimally oxidized LDL induced significantly less cholesterol accumulation in BMMs compared to native LDL. Together, these results demonstrate that selective CE uptake is the primary mode of cholesterol uptake from LDL but not oxidized LDL, a finding that has important implications for cholesterol metabolism in atherosclerotic lesions. Future studies seek to identify the molecular components that participate in the macrophage selective CE uptake mechanism.

This paper explores research on the misinformation effect and hypothesizes a new explanation for the occurrence misinformation effect. Current psychological theories states the misinformation effect occurs when memories are skewed by the presentation of new information after an initial event. This effect has been tested in a multitude of ways, including testing words lists, pictures, colors, and change blindness. Socially, the misinformation effect has been used to explain the inaccuracies of eyewitness testimony. The current judicial system relies on the fallible memory of people and has wrongfully imprisoned numerous innocents. The purpose of this research is to show the misinformation effect is not a problem with memory storage and retrieval, but rather a product of selective stimulus control.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

During past thirty years, several models for non-linear undo models have been presented, but almost none solves undoing and redoing actions in environments, where multiple history buffers are involved and when there are causal dependencies among separate actions. This thesis focuses on developing a new model, which allows a user to select any action from any history buffer. The key part of the model is a smart command design and undo manager, which searches for dependencies and offers possible solutions to the user. The results are presented in the context of the DaemonX framework.