This study contributes to the literature on school reform and restructuring by providing much needed information about effective school organizational practices to ease the transition to high school. As educational researchers and practitioners work to find the best ways to organize high schools for the benefit of teachers and students alike, more attention must be given to the unique needs of ninth graders as they transition to a new school environment while also facing the challenges of adolescence.

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Surface cleaning of gallium nitride (GaN) prior to atomic layer deposition (ALD) of aluminum oxide was investigated at both the atomic as well as device level. Two studies were performed, one in which an ALD process was developed and a second which explored the atomic level origins of defects in the Al₂O₃/GaN system. An ALD process was developed such that a high quality aluminum oxide gate dielectric could be deposited on GaN with only the use of an in-situ TMA pretreatment. This process was developed using a flow type reactor which allowed for the elimination of a hydrogen plasma surface treatment. In the second study, density functional theory modeling was used to examine the likely sources of defects in the Al₂O₃Al2O3 /GaN(0001) system. The modeling revealed that Al₂O₃ is able to passivate the majority of defect states on the GaN(0001) surface, but nucleation of oxide in every unit cell would be required to completely eliminate them. The use of a two-step surface treatment involving a wet clean in HCl and NH₄OH to remove native oxide followed by an in- situ dry clean using hydrogen and TMA was shown to improve the nucleation density. Calculated Dit values were reduced by a factor of 2-3 while border trap densities were reduced a full order of magnitude

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Emerging evidence indicates that epigenetic regulators are critically required for the maintenance of tissue-specific stem cells and that the epigenetic marks are altered in stem cells during physiological aging. Intriguingly, aging-associated stem cell functional decline can be reversed by manipulating epigenetic factors that become dysregulated during aging. These observations lend support to the stem cell theory of aging, which postulates that aging is the result of the inability of tissue-specific stem cells to replenish the tissues with functional differentiated cells that maintain the function of a tissue, and open a new era of research on the epigenetics of stem cell aging that may represent therapeutic potential. Recent advances in single cell technologies are revolutionizing our mechanistic understanding of rare populations of cells, such as stem cells, and offer an unprecedented opportunity to address this challenge.