Corn (Zea mays) is frequently infected by a soil fungal pathogen Aspergillus flavus. The fungus produces aflatoxins, which cause liver cancer. Maize inbred lines that are resistant to infection by A. flavus have been developed, and these inbred lines provide excellent models for studying molecular mechanisms of maize resistance to the fungus. MicroRNA-like RNAs (milRNAs) recently identified in A. flavus had been found to be correlated with aflatoxin production conditions, suggesting that the milRNAs might play a role in the regulation of aflatoxin production. In this research, small RNAs were isolated from kernels of maize (resistant Mp719 and susceptible Va35) inoculated with A. flavus NRRL 3357 (aflatoxigenic) and NRRL 21882 (nonaflatoxigenic) and then subjected to RNA sequencing. Sequencing had identified 69 A. flavus milRNAs and 691 Z. mays miRNAs. The differential expression of some maize miRNAs revealed their potential role in response to inoculation, A. flavus growth, and aflatoxin production.

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The objective of this research is to present a new model for predicting the piezoresistive effect in microflexures experiencing bending stresses. A linear model describing piezoresistivity exists for members in pure tension and compression. Extensions of this model to more complex loading conditions do not match experimental results. An accurate model of piezoresistivity in complex loading conditions would expand the design possibilities of piezoresistive devices. A new model to predict piezoresistive effects in tension, compression, and more complex loading conditions is proposed. The focus of this research is to verify a unidirectional form of this proposed model for microflexures in tension and bending. Implementation of the unidirectional form of the model involves geometric design, stress analysis, and electrical analysis. One of the ways to implement the model is with finite-element analysis (FEA). The piezoresistive FEA for flexures (PFF) algorithm is an FEA implementation of the unidirectional form of the model for flexures. A case study is then given in which the resistance curves of two test devices are predicted with the PFF algorithm. Results from the PFF implementation of the unidirectional form of the model show a close comparison between analytical prediction and experimental results. This new model could contribute to optimized sensors, feedback control of microdevices, nanopositioning, and self-sensing microdevices.

<p> It is well understood that compared with men, women are better able to withstand starvation, have better ultra-endurance capacity, oxidize more fat during endurance exercise, and are more resistant to fat oxidation defects i.e. diet-induced insulin resistance. However, the mechanism(s) for the observed sex differences are unknown. It was my hypothesis that women have greater fat oxidation capacity in skeletal muscle than men.</p> <p> The objectives of my thesis were to determine the mechanism(s) by which women oxidize more lipids; including the role of estrogen as a possible regulator. The most significant findings were that: 1) mRNA for fatty acid oxidation genes are higher in women compared with men, which was confirmed by Stringent Affymetrix GeneChip array analysis, combined with RT-PCR (chapter 2); 2) long-chain acyl-CoA dehydrogenase in human skeletal muscle is not quantifiable despite the majority (90%) of fatty acids oxidized during exercise are long-chain fatty acids (chapter 3); 3) β-oxidation enzymes: tri-functional protein alpha, very long chain acyl-CoA dehydrogenase, and medium chain acyl-CoA dehydrogenase are significantly higher in women compared with men (chapter 4); 4) Acute (8 days) 17β-estradiol supplementation in men significantly increased protein content of β-oxidation enzymes in skeletal muscle, possibly through the regulation of PGC-1α and microRNA (chapter 5).</p> <p> In conclusion, my data provided novel insights into the enhanced ability of women to oxidize fat under periods of metabolic stress by showing that: 1) women are transcriptionally (mRNA) "primed" for known physiological differences in metabolism; 2) women have more protein content of the major enzymes involved in long and medium chain fatty acid oxidation; 3) E2 partially regulates lipid metabolism in skeletal muscle by pre-translational modifications of factors involved in β-oxidation. These findings contribute to the molecular understanding of sex differences in substrate utilization.</p> / Thesis / Doctor of Philosophy (PhD)

<p> Different instructions for associating concrete nouns were given in a paired-associate learning situation. Material was varied to produce different types of interference against which to evaluate the effectiveness of the different instructions.</p> <p> The major findings were: (1) Specific instructions for association produced fewer errors than no specific instructions on the first list a subject learned. (2) After the first list, only the instructions which asked the learner to produce a logical scene from the nouns produced fewer errors than non-specific instructions. (3) Specific instructions did not interact with material.</p> <p> Little evidence was found that the significant instructional effects were due to the specific characteristics of the learners' mediations. These effects were more plausibly attributed to such general mechanisms as either giving the mediations during learning or having learning time occupied with irrelevant activity.</p> / Thesis / Master of Arts (MA)

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