Increased interest has focused on associations between dietary fatty acids and cardiovascular disease (CVD). Current findings delineating effects of consuming saturated fatty acids (SFA) from dairy on CVD risk remain controversial. The objective of this thesis was to investigate the effects of consuming two types of dairy fat, namely those from cheese and butter on, human plasma and RBC fatty acid profiles, compared with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and carbohydrate (CHO). A secondary objective was to investigate the association between consuming these dietary fatty acids and endogenous de novo fatty acid synthesis. A randomized, full-feeding, crossover, single-blinded clinical trial was conducted at the Institute of Nutrition and Functional Foods (INAF), Laval University and Richardson Centre for Functional Foods and Nutraceuticals (RCFFN), the University of Manitoba. A total of 92 women and men with abdominal obesity and relative low high density lipoprotein cholesterol (HDL-C) levels were randomized into a series of 5 treatments. The duration of each treatment was 4 weeks and separated by at least 4 weeks washout period. For plasma fatty acid profile, total plasma SFA after cheese treatment was found to be higher (P<0.05) than after MUFA, PUFA and CHO treatments, whereas total plasma SFA after butter treatment was only found to be higher (P<0.05) than after MUFA and PUFA treatments. Total plasma MUFA after MUFA treatment was higher (P<0.05) than after all other treatments, and total plasma PUFA after PUFA treatment was higher (P<0.05) than after all other treatments. Unlike plasma fatty acid profile, RBC total SFA after two dairy treatments were not higher than after CHO and PUFA treatments. Consistent with the plasma fatty acid profile, RBC total MUFA after MUFA treatment were found to be higher (P<0.05) than after all other treatments. Similarly, RBC total PUFA after PUFA treatment were higher (P<0.05) than after all other treatments. We did not detect any differences in de novo palmitic acid synthesis across all treatments in the present study. However, we did see a positive correlation between de novo palmitic acid synthesis and body fat mass. In summary, present results suggest that consuming dairy fats, from cheese or butter, can significantly modulate plasma fatty acids in a manner that increases plasma total SFA, including myristic acid (C14:0), pentadecanoic acid (C15:0), palmitic acid (C16:0) and heptadecanoic acid (C17:0). However, the effect of consuming dairy fats on RBC fatty acid profile is relatively minor. Additionally, the de novo fatty acid synthesis data suggests that the quality of dietary fatty acids does not associate with human endogenous fatty acid synthesis; unlike body fat mass. / May 2017

Evidence continues to demonstrate that racial/ethnic minority groups experience a disproportionate burden of disease and mortality in cardiovascular-related diseases (CVDs). However, emerging evidence suggests a health advantage for Latinos despite a high risk profile. The current study explored the hospital utilization trends of Latino and non-Latino patients and examined the possibility of an advantage for Latinos within the context of CVD-related events with retrospective data collected over a 12-month period from a local safety-net hospital. Contrary to my hypotheses, there was no advantage for in-hospital mortality, length of stay or re-admission in Latinos compared to non-Latinos; rather, Latinos hospitalized for a CVD-related event had a significantly longer length of stay and had greater odds for re-admission when compared to non-Latinos. Despite data suggesting a general health advantage, Latinos may experience a relative disparity within the context of hospital utilization for CVD-related events. Findings have implications for understanding the hospital utilization trends of Latinos following a CVD-related event and suggest a call for action to advance understanding of Latino cardiovascular health.

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Silicon is widely used in optoelectronic devices, including solar cells. In recent years new forms of silicon have become available, including amorphous, microcrystalline and nano-crystalline material. These new forms have great promise for low cost, thin film solar cells and the purpose of this work is to investigate their preparation and properties with a view to their future use in solar cells. A Hot Wire-Deposition Chemical Vapour Deposition CVD (HW-CVD) system was constructed to create a multi-chamber high vacuum system in combination with an existing Plasma Enhanced Chemical Vapour Deposition (PECVD) system; to study the amorphous to crystalline transition in silicon thin films. As the two chambers were linked by a common airlock, it was essential to construct a transfer mechanism to allow the transfer of the sample holder between the two systems. This was accomplished by the incorporation of two gate valves between the two chambers and the common airlock as well as a rail system and a magnetic drive that were designed to support the weight of, and to guide the sample holder through the system. The effect of different deposition conditions on the properties and structure of the material deposited in the combined HW-CVD:PECVD system were investigated. The conditions needed to obtain a range of materials, including amorphous, nano- and microcrystalline silicon films were determined and then successfully replicated. The structure of each material was analysed using Transmission Electron Microscopy (TEM). The presence of crystallites in the material was confirmed and the structure of the material detected by TEM was compared to the results obtained by Raman spectroscopy. The Raman spectrum of each sample was decoupled into three components representing the amorphous, intermediate and crystalline phases. The Raman analysis revealed that the amorphous silicon thin film had a dominant amorphous phase with smaller contribution from the intermediate and crystalline phase. This result supported the findings of the TEM studies which showed some medium range order. Analysis of the Raman spectrum for samples deposited at increasing filament temperatures showed that the degree of order within the samples increased, with the evolution of the crystalline phase and decline of the amorphous phase. The Selected Area Diffraction (SAD) patterns obtained from the TEM were analysed to gain qualitative information regarding the change in crystallite size. These findings have been confirmed by the TEM micrograph measurements. The deposition regime where the transition from amorphous to microcrystalline silicon took place was examined by varying the deposition parameters of filament temperature, total pressure in the chamber, gas flow rate, deposition time and substrate temperature. The IR absorption spectrum for ƒÝc-Si showed the typical peaks at 2100cm-1 and 626cm-1, of the stretching and wagging modes, respectively. The increase in the crystallinity of the thin films was consistent with the evolution of the 2100cm-1 band in IR, and the decreasing hydrogen content, as well as the shift of the wagging mode to lower wavenumber. IR spectroscopy has proven to be a sensitive technique for detecting the crystalline phase in the deposited material. Several devices were also constructed by depositing the ƒÝc-Si thin films as the intrinsic layer in a solar cell, to obtain information on their characteristics. The p- layer (amorphous silicon) was deposited in the PECVD chamber, and the sample was then transferred under vacuum using the transport system to the HW-CVD chamber where the i-layer (microcrystalline silicon) was deposited. The sample holder was transferred back to the PECVD chamber where the n-layer (amorphous silicon) was deposited. The research presented in this thesis represents a preliminary investigation of the properties of ƒÝc-Si thin films. Once the properties and optimum deposition characteristics for thin films are established, this research can form the basis for the optimization of a solar cell consisting of the most efficient combination of amorphous, nano- and microcrystalline materials.

This article aims at growing (0002) InN film on LiGaO2 substrate by chemical vapor deposition (CVD). High purity InCl3 and metallic indium were used to react with NH3 respectively to form InN. Different experimental condictions such as growth temperature and the reaction pressure were adopted and compared to grow a well crystalline structure and smooth InN thin film. After one hour reaction, InN deposits on LiGaO2 substrate. X-ray diffraction, scanning electron microscope, atomic force microscope, photoluminescence, and transmission electron microscope of the samples were measured to investigate the crystal orientation, crystal quality, surface morphology, and microstructure. Based on the result, we can get the best condiction to grow the InN thin film. Through the experimental results, it is found that InN can not be successfully grown by using metallic indium. Oppositely, it is not difficulty to form InN by using InCl3. After a series of attempts on experiments, the temperature of 600 ¢J and the pressure of 400 torr are found to be the best condiction to grow the InN thin films.

In the thesis, epitaxial ZnO films were grown by chemical vapor deposition method (CVD) on LiGaO2 (001) substrate. Zinc 2,4-pentanedionate monohydrate [Zn (C5H7O2) 2. H2O] , used as the zinc precursor, was vaporized at the temperature between 130 to 140¢J. Then the vapor was carried by a mixture of N2/O2 gas flow into the furnace where the (001) LGO substrate located. The parameters of growth temperature, growth pressure and growth time were adjusted to found the best ZnO films growth conditions. After CVD growth, the crystal structure, crystal quality, surface morphology, optical properties, surface roughness and micro-structure properties of the specimens were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), atomic force microscopy (AFM) and transmission electron microscopy (TEM). This study was divided into three parts. In the first parts, the dependence of growth characteristics on the different growth temperatures was investigated. The best surface morphology and crystal quality of ZnO films were grown under the growth temperature of 550 ¢J. In the second parts, the growth of ZnO films under various pressures was investigated. High orientation (0002)ZnO films were grown at lower growth pressure of 50 torr. In the third parts, the dependence of growth time on the ZnO films quality was investigated under growth temperature of 550 ¢Jand growth pressure of 50 torr.

This study employed a commercial code FLUENT to simulate a chemical vapor deposition process in a rectangular chamber for deposition of a silicon dioxide layer on a rectangular substrate. We focus on the deposition rate and heat transfer coefficient (Nu number) on the substrate surface. We discuss the effects of the size of inlet region, the distance from inlet to substrate, the size of outlet region, the Reynolds number, the temperature of substrate, the ratio of the inlet flow rates of the two reaction gases on the deposition rate. The results show that the four corners at the substrate has the lowest deposition rate no matter how the variables are changed. Near the four corners there exist a region with high deposition rate. The deposition rate is more uniform when inlet is larger or equal to the substrate, and when the distance between the inlet and the substrate is small. The larger the size of the outlet region, the larger the uniform deposition rate region present on the central part of the substrate. The deposition rate increases with increasing Re number. However the uniformity remains similarly. The deposition rate also increases with increasing the substrate temperature. A study of the inlet flow rate ratio of TEOS and indicates that TEOS flow rate governs the process. A proper flow rate ratio gives a better deposition rate.

DLC exhibits an extreme hardness, chemical stability and optical transparency properties, which are, to a certain extent, similar to those of diamond and thus of technological importance. In the case of amorphous hydrogenated carbon (a-C:H) films they can be interpreted as intermediate between diamond, graphite, and polymer-like carbon sites. The most important intrinsic hardness is protection of tools or machine parts against wear. Most modifications have been used on DLC to enhanced mechanical properties, such as reducing its internal compressive stress (N, Si, and metal incorporation), or to reduce its surface energy for further lowering of its already low friction coefficient with 0.1. Among various deposition techniques, microwave generated discharges, especially electron cyclotron resonance (ECR) plasmas, develop excellent a high degree of ionization, high ions densities. In this work, a novel hybrid technique for diamond-like carbon (DLC) film deposition has been developed, which combines the microwave ECR plasma discharging C2H2 and metallic magnetron sputtering. The effects of negative bias voltage and hydrocarbon flow rate for the deposition of a-C:H films on high speed steel were examined by Raman spectra, and their hardness was investigated by the Rockwell method. The Raman spectra show that at different hydrocarbon flow rate, the variation of the G line peak and width, and the integrated intensity ratio ID/IG of DLC and graphic, correlate well with the film hardness. Consequently, we suggest a deposition mechanism of DLC for this combined method.

Highly antiretroviral therapies (HAART) have been implemented to slow the progression of the human immunodeficiency virus (HIV). Although these new advances in the medications for HIV-positive patients have contributed in longer life expectancy, comorbidities, such as cardiovascular disease, still cause higher number of deaths among HIV-positive patients than in the regular population. Because of the intrinsic inflammation caused by the HIV virus, atherogenesis is more likely to occur and is driven by infected macrophages. These macrophages are known to secrete cathepsins, but infection causes the macrophages not to perform their function properly as an immune agent. I hypothesize that antiretroviral drugs play an important role in arterial remodeling by affecting cells within the artery and causing an alteration of cathepsin activity, leading to an increased risk of atherosclerosis in HIV patients. To test this hypothesis, we incubated THP-1 monocytes with antiretroviral drugs efavirenz and tenofovir individually to observe any changes in cathepsin activity. These lysates were analyzed through multiplex cathepsin zymography and quantified through densitometry. We found that our hypothesis held true for efavirenz and tenofovir in THP-1 monocytes, which caused decreased cathepsin K activity compared to vehicle controls. Still, stimulation of peripheral blood mononuclear cells (PBMCs) with efavirenz and tenofovir caused differential effects. Together, our data suggest that the HAART interaction with monocytes that are physiologically relevant to our system possibly contributes to the advancement of atherogenesis in HIV+ patients.

In the cutting tool industry, replaceable cutting edge (insert) is often used. As insert support,steel nets are used which are pre-coated before use, since the iron will affect the coatingquality of the inserts. Titanium carbide (TiC) is an ideal material for pre-coating purposes andthe deposition of TiC is performed by chemical vapor deposition (CVD) using a gaseousmixture of TiCl4, CH4 and H2. In order to optimize both the process time and to ensure goodquality, in this master thesis a series of experiments were designed to investigate the influenceof gas flow rates, the CH4/TiCl4 ratio, and the total pressure. The measured parameters werethe coating thickness and the coating quality. The experimental results showed that increasingthe TiCl4 flow rate resulted in an increased coating thickness, but generated HCl has aretarding effect by adsorption. Increasing the CH4/TiCl4 mole ratio led to higher depositionrates, but outgrowth was observed at high ratios. Increasing the total pressure resulted in anincreased deposition rate, but hazardous TiO2 white smoke was observed.The optimal receipt with higher gas flow, CH4/TiCl4 mole ratio, and depositiontemperatures gave a 3.4 μm thick TiC coating after 12.5 h. Compared with the originalprocess, the optimal process obtained in this thesis saved 47 % process time.Surface morphology and grain size were examined using an optical microscope and ascanning electron microscope, and deposited TiC had a grain size of 1-2 μm. Line profileanalysis using energy-dispersive X-ray spectroscopy showed that the coated TiC layerprevented the diffusion of iron and there was no iron on the surface of the coated steel nets.