Thesis (M.A.)--Ohio University, November, 2009. / Release of full electronic text on OhioLINK has been delayed until September 1, 2014. Title from PDF t.p. Includes bibliographical references.

Bakgrund Matematik kunskaperna har försämrats i de svenska skolorna över tid, därav måste något hända. Därför pågår det en stor statlig vidareutbildning av matematiklärare, Matematiklyftet. Denna fortbildning riktar sig till lärare i årskurs 1-9 i syfte att höja måluppfyllelsen hos eleverna. Eleverna skall således få en mer varierad och utmanade undervisning. Syftet med studien är att undersöka om lärare i årskurs 1-5 beskriver sin undervisning mer inkluderande, efter att de har gått Matematiklyftet. Undersökningen gjordes med hjälp av en kvalitativ metod med semistrukturerade intervjuer som verktyg. Sex lärare från två olika skolor i Västsverige intervjuades. Deras svar spelades in, transkriberades och analyserades. Resultatet tyder på att undervisningen har blivit mer inkluderande efter att lärare deltagit i Matematiklyftet. De intervjuade lärarna anger att de nu i större utsträckning varierar och utmanar eleverna och att de i ökad utsträckning ägnar mer av matematiklektionerna åt problemlösning. Lärarna redogör att de lättare kan anpassa sig till elevers olika kunskapsnivåer.

Today, and for the foreseeable future, coal and other fossil fuels will provide a major portion of the energy services demanded by both developed and developing countries around the word. In order to reduce the emissions of carbon dioxide associated with combustion of coal for electricity generation, a wide range of carbon capture technologies are being developed. This thesis models the oxyfuel carbon capture process for pulverized coal and presents performance and cost estimates of this system in comparison to other low-carbon fossil fuel generators. Detailed process models for oxygen production, flue gas treatment, and carbon dioxide purification have been developed along with the calculation strategies necessary to employ these components in alternative oxyfuel system configurations for different types of coal-fired power plants. These new oxyfuel process models have been implemented in the widely-used Integrated Environmental Control Model (IECM) to facilitate systematic comparisons with other low-carbon options employing fossil fuels. Assumptions about uncertainties in the performance characteristics of gas separation processes and flue gas duct sealing technology, as well as plant utilization and financing parameters, were found to produce a wide range of cost estimates for oxyfuel systems. In case studies of a new 500 MW power plant burning sub-bituminous Powder River Basin coal, the estimated levelized cost of electricity (LCOE) 95% confidence interval (CI) was 86 to 150 [$/MWh] for an oxyfuel system producing a high-purity [99.5 mol% CO2] carbon dioxide product while capturing 90% of the flue gas carbon dioxide. For a CoCapture oxyfuel system capturing 100% of the flue gas CO2 together with all other flue gas constituents, the estimated LCOE 95% CI was 90 to 153 [$/MWh] (all costs in constant 2012 US Dollars). Using the IECM, an oxyfuel system for CO2 capture also was compared under uncertainty to an existing amine-based post-combustion capture system for a new 500 MW power plant, with both systems capturing 90% of the CO2 and producing a high-purity stream for pipeline transport to a geological sequestration site. The resulting distribution for the cost of CO2 avoided showed the oxyfuel-based system had a 95% CI of 44 to 126 [$/tonne CO2] while the amine-based system cost 95% CI ranged from 50 to 133 [$/tonne CO2]. The oxyfuel cost distribution had a longer tail toward more expensive configurations but over 70% of the distribution showed the oxyfuel-based system to be ~10[$/tonne CO2] lower in cost compared to the amine-based capture system. An evaluation of several low-carbon generation options fueled by coal and natural gas further considered both direct and indirect greenhouse gas emissions. This analysis showed oxyfuel to be economically competitive with all capture system considered, and also indicated oxyfuel to be the preferred carbon capture technology for minimizing overall carbon intensity. Combined, these results suggest that oxyfuel is a promising carbon capture technology, and the only one which offers the unique ability to capture all the combustion gases to become a truly zero emission coal plant. Realization of the latter option, however, is contingent on the development of new regulatory policies for underground injection of mixed flue gas streams that is outside the scope of this thesis.

Chemical, physical and sensory properties of omega-3 fatty acid enriched chicken frankfurters developed with flax oil and microencapsulated fish oil at 1.2%, 2.4% and 3.6% were evaluated. Four replicate batches of frankfurters were produced for texture profile analysis and TBARS for assessment of lipid oxidation over four weeks of refrigerated storage. Gas chromatograph analysis indicated that omega-3 fatty acid levels increased (p<0.05) with flax and fish oils treatments resulting in a shift in omega-6/omega-3 with no increase in lipid oxidation over the storage period. The two highest levels of fish oil resulted in increased redness, hardness, gumminess and chewiness (p<0.05) with the highest fish oil having the lowest rating for acceptability. 1.2 and 2.4% flax oil and 1.2% fish oil samples were softer and juicier than commercial frankfurters. Addition of oils high in omega-3 fatty acids to chicken-based frankfurters can result in product resistant to oxidation and acceptable to consumers.

Six week old male obese fa/fa Zucker rats (n=10/group) were fed four different diets enriched in linoleic acid (LA), α-linolenic acid (ALA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) (safflower oil, flaxseed oil, EPA, and DHA oils, respectively) for 8 weeks. Fatty acids were analyzed in major lipid classes in the testes. Global gene expression was analyzed using the Affymetrix Rat Gene 2.0 ST Array. Annotated gene sets from the normal and underdeveloped testes were analyzed using Ingenuity Pathway Analysis (IPA). In lipid analysis, n-3 diet supplementation decreased n-6: n-3 polyunsaturated fatty acid and n-6: n-3 very long chain fatty acids (VLCFA) in most lipid classes in comparison to the LA diet. ALA increased the level of DHA, but not to the same level as DHA diet. Compared to the normal sized testis, the underdeveloped testis showed a marked decrease in n-6 pentaenoic PUFA and VLCFA while increasing n-6 tetraenoic fatty acids. Out of the 3192 genes detected, 1121 and 309 were differentially expressed in the underdeveloped and normal testes, respectively. The IPA indicated that transcripts that are upregulated in the normal testes relative to underdeveloped testes are involved in triacylglycerol biosynthesis, sphingomyelin metabolism and phosphatidylglycerol biosynthesis. Transcripts upregulated in underdeveloped testes relative to normal testes are involved in production of nitric oxide and reactive oxygen species. Downstream effect analysis showed an increased trend towards reproductive system diseases and endocrine system disorders in the underdeveloped testes compared to the normal testes. In conclusion, these results indicate that testicular lipids and their metabolism are closely related with normal testis development and function. / February 2016

A series of experiments were conducted to examine the effect of petroselinic acid, found in coriander oil, on fillet, hepatocyte and whole body FA composition and Δ6 desaturase gene expression in hepatocytes of rainbow trout (Oncorhynchus mykiss) fed vegetable oil (VO) based diets containing no fishmeal (FM) or fish oil (FO). In the first experiment, rainbow trout were fed one of eight diets containing fish, flax, canola or Camelina sativa oil with or without coriander oil. Coriander oil in the diet increased concentrations of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3, P < 0.05) in the fillet. There was a trend to increased 20:5n-3 + 22:6n-3/20:4n-6 ratios when coriander oil was added to the diet (P = 0.067). The second trial set out to investigate the effects of varied levels of coriander oil in canola oil based diets, on i) the capacity of rainbow trout hepatocytes to desaturate, elongate and esterify [1-14C] α-linolenic acid (18:3n-3; ALA) and [1-14C] linoleic acid (18:2n-6, LA), ii) reducing the production of 20:4n-6 in hepatocytes and iii) gene expression. This experiment demonstrated a significant increase in 22:6n-3 (P = 0.011) and a decrease 20:4n-6 (P = 0.023) in rainbow trout hepatocytes. Furthermore, there was a three-fold decrease in acetate for the [1-14C] 18:2n-6 and nearly a two-fold increase for the [1-14C] 18:3n-3 substrate when coriander was added at increasing levels, illustrating an increase in peroxisomal β-oxidation. Relative gene expression of ∆6 desaturase decreased with addition of coriander oil at the 0.5 inclusion level of coriander oil. The final experiment was conducted to determine if bypassing the first ∆6 desaturase and rate-limiting step in the n-3 FA pathway causes increased conversion of stearidonic acid (SDA; 18:4n-3) to 20:5n-3 and 22:6n-3. Rainbow trout were fed one of six diets containing either fish, conventional linseed (flax), or SDA enriched linseed oil (LO) with and without coriander oil. Inclusion of coriander oil did not affect any growth or feed intake parameters of rainbow trout. However, the addition of coriander oil caused a significant increase in whole body 22:6n-3 and 20:4n-6 concentrations in fish fed SDA enriched LO with coriander oil (SDA+C) compared to fish fed conventional linseed oil (LO). These results suggest that petroselinic acid, found in coriander oil, has the ability to influence FA bioconversion of the n-3 and n-6 FA pathway thereby increasing 22:6n-3 and possibly 20:5n-3 in rainbow trout and reducing ARA when fed VO-based diets. Furthermore, it seems as though petroselinic acid causes improved bioconversion to 22:6n-3 when the first ∆6 desaturase is bypassed. Further studies are needed to determine the mechanism of action that petroselinic acid has on FA bioconversion.

Phaeodactylum et Nannochloropsis sont des espèces photosynthétiques modèles pour le métabolisme des glycérolipides, se distinguant par un enrichissement en acides gras polyinsaturés à très longues chaînes (VLC-PUFA) et de grandes quantités en triacylglycérol (TAG). Les proportions des différents lipides sont influencées par des facteurs environnementaux. Nous avons caractérisé le remodelage lipidique chez Phaeodactylum en réponse à la carence en azote et en phosphate. Ces limitations en nutriments induisent une accumulation de TAG, exploitable comme biocarburant. Nous avons identifié de nouveaux composés induisant l'accumulation de TAG et étudié le rôle potentiel du monoxyde d’azote (NO•) dans la régulation du métabolisme lipidique. Nous avons montré qu’en fonction du site de production, le NO• était un signal émis lorsque les conditions de vie étaient critiques, déclenchant l'accumulation de TAG.Les VLC-PUFAs sont produits par des élongases et des désaturases localisées dans le RE. Nous avons identifié une nouvelle classe d’élongases d’acides gras saturés, agissant sur le 16:0, et appelées Δ0-ELO. Le knock out de Δ0-ELO1 de Nannochloropsis réduit le niveau du monogalactosyldiacylglycérol (MGDG), principal lipide des chloroplastes. Ce phénotype met en évidence le rôle de Δ0-ELO1 dans la «voie oméga» qui contrôle le trafic des VLC-PUFAs. Nous avons débuté une dissection de la «voie oméga» par des approches de génétique et des analyses du remodelage lipidique à basse température chez Nannochloropsis. Le diacylglycéryl hydroxyméthyltriméthyl-β-sérine (DGTS) apparaît comme le précurseur de base pour importer des VLC-PUFAs vers le chloroplaste, suivant une voie très régulée du DGTS au MGDG. De plus nous avons montré des fonctions possibles du MGDG et des VLC-PUFAs dans la photoprotection et la régulation de la fluidité membranaire latérale. / Phaeodactylum and Nannochloropsis are photosynthetic model species for glycerolipid metabolism, standing out by an enrichment of very-long-chain polyunsaturated fatty acids (VLC-PUFAs) and high contents of neutral lipids such as triacylglycerol (TAG). Lipid profiles are influenced by environmental factors. We characterized the lipid remodelling occurring in Phaeodactylum in response to nitrogen and phosphate starvation. Nutrient limitations induce neutral lipid accumulation, which may be exploited as biofuels. We identified new triggers of TAG accumulation and investigated a potential role of nitric oxide (NO•) as second messenger in the regulation of neutral lipid levels. We conclude that in dependence of the production site, NO• serves as a signalling molecule for critical life conditions and thereby triggers TAG accumulation.VLC-PUFAs are produced by ER-located elongases and desaturases. We identified a novel class of elongases, called Δ0-ELOs, acting on saturated fatty acids, most importantly 16:0. Knock out of Δ0-ELO1 in Nannochloropsis resulted in reduced monogalactosyldiacylglycerol (MGDG) levels. MGDG is the major chloroplast lipid. This indicated a role of this initial elongase in fatty acid fate determination and thus in the elusive “omega pathway” for VLC-PUFA trafficking. We have started to investigate the “omega pathway” by reverse genetic approaches and analyses of low-temperature induced lipid remodelling in Nannochloropsis. Diacylglyceryl hydroxymethyltrimethyl-β-serine (DGTS) appears most likely at the base for the chloroplast import of VLC-PUFA, following a dynamically regulated DGTS-to-MGDG pathway. Additionally, we gave insights into possible functions of MGDG and VLC-PUFA in photoprotection and regulation of membrane fluidity.

The aim of this thesis was to verify the hypothesis implying that n-3 polyunsaturated fatty acids inhibit the development of mild chronic inflammation. The experiment was conducted on rats with different diets (control, with the addition of safflower oils, fish oils and oils from algae Schizochytrium). For processing the results of the collected tissues was used determination of expression of selected genes by qRT-PCR, detection of proteins and in the cytosol and nuclear fractions by Western blot and the quantification of cytokines by ELISA. Feeding oil from algae Schizochytrium has led to lowering the final weight and blood glucose, further to enhance expression of PPAR-gama and increasing the production of anti-inflammatory cytokines IL-10 and TGF-beta1. In kontrast, no difference was observed in the expression of GPR120 and adiponectin receptors or proteins in an amount of NF-kappaB and PPAR-gama between diets. Elevated plasma levels of adiponectin were found. The results of the experiment shows that it is possible to recommend oil from algae Schizochytrium as a useful supplement of human diet as prevention of chronic degenerative diseases.

The aim of my thesis was to assess the influence of polyunsaturated fatty acids n 3 (DHA and EPA) on gene expression, mainly PPARy, in model organism. The expression of PPARy gene is increased by these polyunsaturated fatty acids and thus they decrease the risk of development of inflammation and atherosclerosis. This hypothesis was tested on 40 test rats (Wistar albino). The first 7 weeks the rats were fed with a diet containing beef tallow and sweet condensed milk until they manifested mild obesity and inflammation. During other 7 weeks they were divided into 4 groups, each containing 10 individuals. One of the groups was further fed with diet containing beef tallow (control group), other groups received diet with 6% content of oil from safflower added, 6% content of fish oil (high content of EPA) or 6% content of oil from Schizochytrium alga (high content of DHA). The expression of PPARy was measured by using molecular-biology methods at the end of the trial. It was proven that the diet rich on DHA increases PPARy gene expression (P<0,05). The increase of PPARy gene expression in a diet containing fish oil was inconclusive (P>0,05). With these results we confirmed the hypothesis that diet rich on PUFA n3 decreases the risk of inflammation development and atherosclerosis and that DHA is significantly more effective.

The change in the hydrological cycle due to climate change entails more frequent and intense rainfall. As a result, urban water systems will be disproportionately affected by the climate change, especially in such urban areas as Las Vegas, which concentrates its population, infrastructure, and economic activity. Understanding the proper management of urban stormwater in the changing climate is becoming a critical concern to the water resources managers. Proper design and management of stormwater facilities are needed to attenuate the severe effects of extreme rainfall events. In an effort to develop better management techniques and understanding the probable future scenario, this study used the high-resolution climate model data conjunction with advanced statistical methods and computer simulation. Las Vegas Valley which has unique climatic condition and is surrounded by the mountains in every direction was chosen for the study. The North American Regional Climate Change Assessment Program is developing multiple high-resolution projected-climate data from different combinations of regional climate models and global climate models. First, the future design depths was calculated using generalized extreme value method with the aid of L-moment regionalization technique. The projected climate change was incorporated into the model at the 100 year return period with 6h duration depths. Calculation showed that, the projection from different sets of climate model combinations varied substantially. Gridded reanalysis data were used to assess the performance of the climate models. This study used an existing Hydrologic Engineering Center’s Hydrological Modeling System (HEC-HMS) model and Storm Water Management Model (SWMM) developed by the Environmental Protection Agency (EPA) were implemented in the hydrological simulation. Hydrological simulation using HEC-HMS showed exceedances of existing stormwater facilities that were designed under the assumption of stationarity design depth. Low Impact Developments such as permeable pavement and green roof were found to be effective in the attenuation of climate change induced excess surface runoff. The primary purpose of this study is understanding of proper designing, planning and management of the urban stormwater system in the predicted climate scenarios.