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Functional foods, including whole, fortified, enriched, or enhanced foods, provide variety of health benefits beyond the basic function of supplying essential nutrients. The consumption of functional foods has been commonly linked with the lower risks of metabolic diseases, including cardiovascular disease, type 2 diabetes (T2DM), and certain types of cancer. However, not all these health claims on marketed functional foods are supported by solid experimental evidence and mechanistic investigation. With more complex chemical constituents than nutraceuticals or dietary supplements, functional foods can affect diverse targets in humans and animals, including both host cells and microbes, through different reactions and pathways. All these features of functional foods pose challenges in defining their bioactivities and underlying mechanisms as well as the recommended doses of intake in practice. Therefore, comprehensive examination on the metabolic effects of functional foods is needed to address those questions. In this project, the influences of Scenedesmus algae, functionalized wheat bran (FWB), and Konjac mannan-oligosaccharides (kMOS), which are whole, fortified, and enriched functional foods, respectively, on animal performance were determined in mouse trials. Their metabolic effects were examined by the comprehensive liquid chromatography-mass spectrometry (LC-MS)-based metabolomics and biochemical analysis. The results are summarized as follows: (1) Scenedesmus feeding promoted the growth at the low dose through the elevation of antioxidants, the expansion of purine nucleotide cycle, and the modification of microbial metabolism, while inhibited it at the high dose through oxidative stress, disrupted urea cycle and lipidome, and the upregulation of fatty acid oxidation. (2) FWB feeding yielded beneficial effects on cholesterol, microbial metabolism, and purine metabolism, while it also negatively affected the nutritional status by decreasing the bioavailability of essential amino acids and choline. (3) The remodeling of microbiota- derived intestinal metabolome only occurred under the high-dose MOS feeding, while the changes of hepatic metabolites in glycolysis and TCA cycle occurred in all doses. Therefore, kMOS induced different dose-dependent responses in the gut microbiome and the hepatic metabolome. Overall, double-edged and dose-dependent metabolic effects were observed in the feeding studies of these functional foods. All these information warrant further investigation on the functions of individual constituents of functional foods as well as their combinatorial effects in the biological systems in order to disentangle the “harmful” from the “beneficial” effects of functional foods for their usages in humans and animals.

Wind is one of the most promising renewable energy forms that can be harvested to into the electrical power system. The installation has been rising worldwide in the past and will continue to steadily increase. The high penetration of wind energy has bought about a number of difficulties to the power system operation due to its stochastic nature, lack of exhibited inertia, and differing responses to the traditional energy sources in grid disturbances. Various grid support functions are then proposed to resolve the issues. One solution is to allow the renewable energy sources to behave like a traditional synchronous generator in the system, as a virtual synchronous generator (VSG). On the other hand, testing the control of the future power grid with high penetration renewable often relies on digital simulation or hardware-based experiments. But they either suffer from fidelity and numerical stability issues, or are bulky and inflexible. A power electronics based power system emulation platform is built in the University of Tennessee. This Hardware Testbed (HTB) allows testing of both system level and component level controls, with a good balance between the fidelity of the hardware-based testing platform, and the coverage of the digital simulation.This dissertation proposal investigates the VSG operation of the full converter wind turbine (FCWT), focusing on its control and testing in the HTB. Specifically, a FCWT emulator was developed using a single converter to include its physical model and control strategies. The existing grid support functions are also included to demonstrate their feasibility.The comprehensive VSG controls are then proposed for a FCWT with short term energy storage. The dynamic response of the FCWT can be comparable to the traditional generation during grid disturbance. The control can also allow the FCWT to be dispatched by the system operator, and even operate stand-alone without other grid sources.To study the system response under faults, a short circuit fault emulator was developed in the HTB platform. Four basic types of the short circuit faults with various fault impedance can be emulated using the emulator. The power system transient stability in terms of critical clearing time can be measured using the developed fault emulator.

Algae have been investigated and developed as a source of food, dietary supplement, and biofuel, due to their chemical and nutrient composition. Algae consumption carries algal proteins, polyunsaturated fatty acids (PUFAs), vitamins, dietary fibers, and bioactive compounds into the biological systems of humans and animals, and therefore are expected to elicit metabolic and physiological responses. Numerous efforts have been undertaken to understand the health-promoting effects of algae consumption, such as their hypolipidemic, antioxidant, anti-obesity and anti-cancer properties. However, the metabolic events in algae-elicited effects were not examined in details in spite of the fact that these benefits are largely based on the metabolic interactions between algal components and the biological system. In this study, the influences of consuming green algae (Scenedesmus sp.) on the metabolic status of young mice was investigated through growth performance, blood chemistry, and liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. Compared to the control diet, 5% algae promoted growth performance while 20% algae suppressed it. The growth performance was significantly increased by 5% algae but decreased by 20% algae feeding. Serum glucose, triacylglycerols (TAG), and blood urea nitrogen (BUN) levels were not affected by both treatments, but serum cholesterol level was dramatically decreased by 20% algae feeding. Metabolomic analysis of liver, serum, feces and urine samples revealed diverse influences of algae feeding on mouse metabolome, which are represented by the features as follows: 1). Urinary vitamins and fecal pigments are identified as robust exposure markers of algae feeding. 2). Despite the high-level protein in algae, the impacts of algae feeding on free amino acids in serum and the liver were quite limited. 3). Algae feeding increased the PUFA levels in serum and liver lipidomes and the free fatty acids in feces. 4). 5% algae increased the level of reduced glutathione (GSH) in the liver while 20% algae increased the level of oxidized glutathione (GSSG) in the liver and the levels of aldehydic lipid oxidation products (LOPs) in the liver and urine. 5). 5% algae selective increased the levels of intermediate metabolites, including adenosine monophosphate (AMP), adenylsuccinic acid, dephospho-CoA, and nicotinamide, in the liver while 20% algae increased the levels of carnitine and carnitine derivatives in the liver. 6). Algae feeding dramatically altered the microbial metabolism, as reflected by the increases in short-chain fatty acids (SCFAs) and primary bile salts in feces, the increases of branched fatty acids in urine, the decreases of secondary bile acids in feces, and the decrease of p-cresol metabolites in urine. Overall, multiple correlations between metabolite markers and growth performance in algae feeding were established in this study and could serve as a foundation for further mechanistic investigations on the biological effects of algae feeding.

Polymer transport with complex fluid rheology was implemented into an existing hydraulic fracturing simulator (CFRAC), and the implementation was extensively validated. Shear thinning viscosity was included for polymer fluid flow in both porous media and fractures. Shear thickening viscosity was implemented for flow in the matrix. Polymer injections were simulated to investigate the effect of polymer rheology, including both shear thinning and shear thickening behaviors, on polymer injectivity and on the possibility of induced hydraulic fracturing. The results indicated that shear thickening decreases injectivity and can induce initiation of hydraulic fractures. The hydraulic fractures substantially enhance injectivity, and eliminate the reduction in injectivity due to shear thickening. Pressure fall off tests were simulated to study the effect of polymer rheology on the identification of hydraulic fractures from the shut-in transient after shut-in. The results showed that standard methods from pressure transient analysis can be applied to diagnose the presence hydraulic fracturing by identifying a linear flow regime and fracture closure on a Bourdet derivative plot and a square root of time plot. It was found that these methods are effective regardless of shear thickening and shear thinning rheology. However, the results suggested that if the fracture is small and closes quickly, this could cause difficulty for the diagnosis.