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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
820741

A Fuzzy Real Option Model for Pricing Grid Compute Resources

Allenotor, David 21 January 2011 (has links)
Many of the grid compute resources (CPU cycles, network bandwidths, computing power, processor times, and software) exist as non-storable commodities, which we call grid compute commodities (gcc) and are distributed geographically across organizations. These organizations have dissimilar resource compositions and usage policies, which makes pricing grid resources and guaranteeing their availability a challenge. Several initiatives (Globus, Legion, Nimrod/G) have developed various frameworks for grid resource management. However, there has been a very little effort in pricing the resources. In this thesis, we propose financial option based model for pricing grid resources by devising three research threads: pricing the gcc as a problem of real option, modeling gcc spot price using a discrete time approach, and addressing uncertainty constraints in the provision of Quality of Service (QoS) using fuzzy logic. We used GridSim, a simulation tool for resource usage in a Grid to experiment and test our model. To further consolidate our model and validate our results, we analyzed usage traces from six real grids from across the world for which we priced a set of resources. We designed a Price Variant Function (PVF) in our model, which is a fuzzy value and its application attracts more patronage to a grid that has more resources to offer and also redirect patronage from a grid that is very busy to another grid. Our experimental results show that the application of the PVF has helped achieve equilibrium between users satisfaction measured as QoS and recovery of the infrastructure investment made by the providers. In the absence of pricing benchmarks, we setup Commodity Base Prices (CBP) and then integrated our PVF and CBP with GridSim to price grid compute resources. In summary, this thesis provides the design of a model to price grid compute resources using financial options theory. The model achieves mutual benefit for users and providers in the grid environment. The mutual benefit is expressed in terms of QoS to the users and recovery of investments on the grid infrastructure for the providers. This thesis has opened up many different opportunities for further research especially in the era of enterprise computing with clouds.
820742

Effects of water level management on water chemistry and primary production of boreal marshes in northern Manitoba, Canada

Watchorn, Kristen Elise 31 January 2011 (has links)
This experiment manipulated water levels in boreal marshes within the Saskatchewan River Delta, a 9500 km2 region in northern Canada. Water levels in three wetland cells were lowered in a partial drawdown by a mean of 0.32 m. Water clarity, nutrient concentrations, and periphyton nutrient limitation were measured over the summer preceding and the summer following manipulation. The water levels of three adjacent control wetlands were not manipulated. Lowering wetland water levels reduced the wind velocity necessary to resuspend bottom sediments, which led to increases in turbidity, dissolved organic carbon, and concentrations of organic and inorganic nitrogen and phosphorus. Prior to drawdown, wetland periphyton communities were limited by nitrogen or co-limited by nitrogen and phosphorus. The input of nutrients from the sediment resulted in a shift from nutrient deficiency to nutrient sufficiency. Periphyton and phytoplankton production increased in response to the nutrient input. Increased turbidity, nutrient concentrations, and algal production were correlated with depth, rather than being inherent to the drawdown condition. Other water level manipulation studies have found that a reflood after a period of total drawdown caused a pulse of nutrients leaching from decomposing litter. This work suggests that these changes may not require complete drying out of sediments, or the input of large amounts of litter from drowned annual mudflat species, but rather can occur when depths are shallow enough that sediments are more frequently resuspended by wind. These findings have implications for future management of these marshes for waterfowl and muskrat production.
820743

Identification and analysis of Rob, a transcriptional regulator from Serratia marcescens

Nasiri, Jalil 02 February 2011 (has links)
Serratia marcescens, a member of Enterobacteriaceae family, is a causative agent of nosocomial and opportunistic infections. Numerous reports show that the multidrug resistance among S. marcescens is growing. This organism has high-level intrinsic resistance to a variety of antimicrobial agents, which makes the treatment of infections caused by this bacterium very difficult. The major mechanism for antibiotic resistance, especially to fluoroquinolones, in Gram-negative organisms is the active efflux of the antibiotic molecule mediated by efflux pumps belonging to the Resistance-Nodulation-Cell Division (RND) family. It was previously shown that the SdeAB and SdeXY multidrug efflux pumps are important for conferring the intrinsic drug resistance in S.marcescens. In Escherichia coli, the up-regulation of transcriptional activators, such as MarA, SoxS and Rob, affect transcription of acrAB, tolC and micF. Over-expression of Rob results in increased expression of the E. coli AcrAB-TolC efflux pump and decreases outer membrane permeability through up-regulation of micF, resulting in multidrug, organic solvent and heavy metal resistance. In the present study, we report the identification of a rob gene in S. marcescens which has a 70% identity at the DNA level and 71% identity at the amino acid level to that of E. coli. Moreover, the S. marcescens rob demonstrated similar properties to the E. coli rob including having an effect on expression of outer membrane protein F (OmpF) and over-expression of SdeAB and SdeXY, conferring antibiotic resistance to divergent antibacterial agents and tolerance to organic solvents. We performed rob promoter evaluations using transcriptional fusions to the Green Fluorescence Protein (GFP) in the vector pGlow-TOPO and constructed a rob knock-out using the TargeTron Gene Knockout System. Promoter activity assessment, using the pGlow-TOPO reporter plasmid, showed that rob had higher promoter activity at 37°C than 30°C. In the presence of 2,2’-dipyridyl, rob promoter activity was observed to be slightly increased in the early and mid-log phase by 1.4 and 1.1 fold, respectively. We also showed that sodium decanoate and sodium salicylate can reduce the transcription of rob at 30°C and 37°C. This reduction was observed more potently when rob was exposed to sodium decanoate at 30°C. Minimum inhibitory concentration (MIC) for various antibiotics of the S. marcescens rob knock-out demonstrated a decrease in susceptibility to nalidixic acid, tetracycline, chloramphenicol, ciprofloxacin, norfloxacin, and ofloxacin. Over-expression of rob resulted in an increased resistance by 4, 2, and 2-fold to nalidixic acid, tetracycline and chloramphenicol, respectively. In addition, rob over-production displayed 8, 4, and 4-fold increase in resistance to ciprofloxacin, norfloxacin, ofloxacin, respectively. To discover the role of rob in the efflux mechanism, we performed ethidium bromide accumulation assays on over-expressing and knock-out strains. Organic solvent tolerance assays were carried out using n-hexane to determine if rob is involved in expression of efflux pumps. We found the rob null mutant to be sensitive to n-hexane while the over-expression of rob resulted in resistance to n-hexane. RT-PCR of the rob knock-out strain showed a decrease in expression of micF, ompC, sdeXY, sdeAB and tolC, respectively, and an increase in the expression of ompF. To conclude, we identified a rob homolog in S. marcescens which contributes to resistance to multiple antibiotics and tolerance to organic solvent.
820744

The behavioral ecology of the American Wigeon (Anas americana) over its annual cycle

Wishart, Richard A. 31 March 1983 (has links)
The behavioral ecology of the American Wigeon (Anas americana) was studied over its annual cycle in western Canada between 1974 and 1978. The objective of this work was to examine the cross-seasonal interactions of the biology and behavior of the wigeon as they underlie the evolution of its mating system. The wigeon was more herbivorous than any other dabbling duck studied so far and spent a considerable amount of time feeding in upland habitats. Vegetation was important in the diet year round but particularly from late summer through the winter. Plant seeds were a rich source of protein and carbohydrate early in the spring. During breeding stages animal foods were selected by wigeons, particularly females. Wigeons usually did not feed on small crustaceans and gastropods but selected larger aquatic insect foods. Relative to other Anas soecies, the wigeon has a goose-like bill whose structure facilitates feeding on upland and aquatic vegetation. With the evolution of this specialization, efficient surface-straining of small foods has been sacrificed. To increase food digestibility, wigeons altered gizzard grit composition and organ sizes. Through these mechanisms I have demonstrated how wigeons have been able to increase the efficiency of digestion.
820745

Artificial land drainage in Manitoba: history, administration, law

Elliott, William P. 01 January 1977 (has links)
A history of the development and organization of artificial land drainage in Manitoba and the involvement of statutory authorities in land drainage is reviewed. The Department of Mines, Resources and Environmental Management Water Resources Division, conservation districts and municipal governments divide jurisdiction and responsibility over watercourses in Manitoba. The Prairie Farm Rehabilitation Administration and the Manitoba Department of Agricultural Technical Services Branch provide conditional assistance to farmers contemplating slough drainage. The Agricultural and Rural Development Agreement and the Fund for Rural Economic Development Program contain comprehensive drainage programs in Manitoba. The common and statute law concerning drainage is reviewed. Legal drainage procedures for individuals, rural municipalities, conservation districts and the Province of Manitoba are outlined. In addition, procedures for obtaining drainage assistance from the Manitoba Department of Agriculture and the Prairie Farm Rehabilitation Administration are also presented. Many statutory provisions concerning drainage in Manitoba are obscure and inconsistent. Clarification of these provisions is sorely needed before drainage law can be used as an effective tool in a wetland preservation effort.
820746

Autumn field-feeding patterns of the wild mallard duck (Anas platyrhynchos)

Ball, Garth 31 September 1983 (has links)
Sixteen adult male and 8 adult female post moult mallards were equipped with radio transmitters, in a two year study (1977-6AHY-M and 4AHY-F; 1978-10AHY-M and 4AHY-F). Field-feeding was monitored at a lure crop and on adjacent grain fields. Ninety-two percent of the mallards radio-equipped were recorded at a field-feeding site at least once with 71% recorded field-feeding within one week. There was no significant difference in field-feeding activity between males and females. In the morning during periods of rain, mallards field-fed 0.55h longer, arriving 0.30h later and departing 0.9h later than mallards field-feeding during clear weather. The morning field-feeding period was longer in duration than the evening foeld-feeding period. Light intensity was the dominant climatological variable contributing to the arrival of mallards in the morning during periods of no rain (multiple R2=68.1%) and rain (R2=69.5%). Light appeared to act as an initiating cue for morning feeding activity. A high correlation existed between duration of stay during periods of no rain (r=0.815) and rain (r=0.860) suggesting that mallards remained longer at a field-feeding site in the morning by departing later, not arriving earlier. Light intensity was also the dominant climatological variable contributing to the arrival of mallards in the evening amongst those mallards which field-feed in both the morning and evening (R2=78.1%) and those which field-fed in the evening only (R2=63.3%). In addition, light intensity was the only contributing factor in the evening for all mallards departing a field-feeding site (R2=72.7%). Mallards were never recorded field-feeding longer than 15 minutes after there was non measurable light...
820747

Effects of whole and fractionated yellow pea flours on indices of cardiovascular disease, diabetes and thermogenesis as well as the gastrointestinal microbiome

Marinangeli, Christopher 07 February 2011 (has links)
Whole yellow pea flour (WPF) and fractionated yellow pea flour (FPF) are novel functional food ingredients that vary in nutritional composition. Consequently, the health benefits of WPF and FPF remain undefined. The purpose of this research was to identify the effects of WPF and FPF on risk factors and morbidities associated with cardiovascular disease, diabetes and obesity as well as the gastrointestinal microbiome. Using USDA recommended dosages of WPF and FPF, clinical endpoints and the colonic microbiome were investigated using a human clinical trial engaging a cross-over design and a diet and energy controlled paradigm. Humans were also utilized to investigate post-prandial glycemic responses and sensory characteristics of novel functional foods formulated with WPF. Finally, Golden Syrian hamsters were used to assess the impact of high doses of WPF and FPF on clinical endpoints and caecal microbial abundance. Results reveal that USDA recommended dosages of WPF and FPF in humans decreased (p<0.05) fasting insulin and estimates of insulin resistance compared to white wheat flour (WF). Android-to-gynoid fat ratios in women were lower (p=0.027) in the WPF group compared to the WF group. FPF decreased (p<0.05) post-prandial energy expenditure alongside a tendency (p<0.075) to reduce carbohydrate oxidation. Novel biscotti and banana bread formulated with WPF induced low post-prandial glycemic responses which were similar to boiled whole yellow peas and significantly lower (p<0.05) than white bread. Sensory analysis of novel WPF biscotti and banana bread demonstrated that WPF-based food products are palatable and acceptable for human consumption. Hamsters consuming diets containing 10% WPF and FPF induced similar reductions (p<0.05) in fasting insulin levels compared to controls. However, animals consuming WPF increased (p<0.05) oxygen consumption while FPF decreased (p<0.05) fasting glucose levels. In addition, terminal restriction fragment length polymorphism analysis revealed that WPF and FPF induced distinct shifts in caecal microbial populations within the phyla Firmicutes. Finally, pyrosequencing analysis of human fecal microbiota demonstrated that FPF and WPF induced shifts in bacterial genera, primarily within Bacteroidetes and Firmicutes. In conclusion, whole and fractionated yellow pea flours are functional food ingredients and can be utilized to manage risk factors for lifestyle-related diseases in humans.
820748

Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009

Simner, Patricia Jeanne 23 February 2011 (has links)
The spread of resistance to the cephalosporins in the Enterobacteriaceae and more specifically within E. coli is a continuing cause of public health concern, with such resistance increasingly seen in community- and nosocomial-acquired infections. Extended-spectrum ß-lactamase (ESBL) and AmpC ß-lactamase (AmpC) enzymes cause most cephalosporin resistance in E. coli by hydrolysis of the antimicrobial and continue to jeopardize patient outcome. The purpose of this thesis was to determine the prevalence of ESBL-producing Enterobacteriaceae and to molecularly characterize ESBL and AmpC producers found to be associated with the increasing cephalosporin resistance among E. coli within Canadian hospitals from 2005 to 2009. Isolates were collected as part of the Canadian Intensive Care Unit and Canadian Ward surveillance studies. ESBL and AmpC producers were molecularly characterized for resistance genes, virulence factors and phylogenetic groups. All strains were typed using PFGE and ESBL-producing E. coli were further typed by MLST. Plasmids bearing the ESBL and AmpC genes were characterized by BglII RFLP analysis and a multiplex PCR for replicon typing. ESBL-producing E. coli and K. pneumoniae and AmpC-producing E. coli were found to be firmly established in Canadian hospitals; whereas, ESBL-producing K. oxytoca and P. mirabilis have yet to emerge. Increasing resistance to several unrelated antimicrobials leading to multi-drug resistance among these pathogens is concerning. The successful dissemination of ESBL-producing E. coli in Canada occurs through a diversity of different mechanisms and does not correspond to a single ESBL determinant, or a single clone, or a single plasmid but rather through the combination of clonal spread of virulent strains and the acquisition of diverse ESBL-bearing plasmids. However, the predominance of CTX-M-15-producing E. coli in this study was mainly due to the virulent ST131 clone and the diverse IncFII plasmids bearing the blaCTX-M-15 gene. Whereas, horizontal transfer of genetically similar IncI1, IncA/C and IncK/B plasmids bearing blaCMY-2 and the clonal spread of virulent strains, including ST131 with ampC promoter/attenuator mutations, appears to be playing a role in the spread of AmpC-producing E. coli isolates in Canadian hospitals. The increasing prevalence of these multi-drug resistant pathogens in Canadian hospitals demonstrates the need for increased surveillance and understanding of these emerging pathogens. The continued surveillance will help guide proper infection control procedures and identify optimal treatment of these clinically important pathogens in Canadian hospitals.
820749

"Indianness" and the fur trade: representations of Aboriginal people in two Canadian museums

Richard, Mallory Allyson 28 February 2011 (has links)
This project examines whether recent changes to the relationships between museums and Aboriginal people are visible in the museum exhibits and narratives that shape public memory. It focuses on references to the fur trade found in the Canadian Museum of Civilization’s First Peoples Hall and Canada Hall and throughout the Manitoba Museum, using visitor studies, learning theory and an internal evaluation of the Canada Hall to determine how and what visitors learn in these settings. It considers whether display content and visual cues encourage visitors to understand the fur trade as an industry whose survival depended on the participation of Aboriginal people and whose impacts can be viewed from multiple perspectives.
820750

Le héros romantique dans « Le Rouge et le Noir » de Stendhal, « Illusions perdues » de Honoré de Balzac, « L’Éducation sentimentale » de Gustave Flaubert et « Les Travailleurs de la mer » de Victor Hugo

Kon, Lea 28 February 2011 (has links)
Cette étude thématique, sociocritique et philosophique fait ressortir la présence du romantisme dans les œuvres traditionnellement conçues comme réalistes dans le cadre de la littérature française du XIXe siècle. Cette recherche extrapole les attributs romantiques par l’agent du héros romantique dans Le Rouge et le Noir de Stendhal, Illusions perdues de Honoré de Balzac, L’Éducation sentimentale de Gustave Flaubert et Les Travailleurs de la mer de Victor Hugo. Cette étude précise que l’archétype du héros romantique devient un délégué du romantisme, et dans chaque œuvre, son rôle est défini par cette liaison au romantisme qui affirme et le fait dépasser la catégorisation comme un être appartenant au roman de formation et également comme l’incarnation du désenchantement de l’époque. Le héros romantique est l’enfant sublime qui désire l’union à l’Absolu, le poète et le mage, ce qui le rend déplacé dans la société bourgeoise dont l’ampleur augmente considérablement à cette époque. Certes, il faut souligner les tendances de ces figures romantiques à s’immerger dans la société. Les héros romantiques présentés sont motivés simultanément par les pulsions au sublime et aux manipulations sociales dans le but d’accéder au pouvoir et à la gloire sociale. La double appartenance mène à la déchirure, à la capitulation de soi et subséquemment à la fatalité. Cette étude renforce que le héros romantique est simultanément diminué et valorisé pour demeurer la figure dominante des œuvres même de la seconde moitié du XIXe siècle. De plus, ces œuvres traitent le romantisme comme un personnage non humain, fournissant une manière de présenter la polémique à propos des personnages, thèmes, esprit, genres et la validité du romantisme.

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