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The majority of adolescents in the United States do not obtain the recommended amount of sleep each night. While the reasons for this are multi-factorial, early school start times effect the amount of sleep an adolescent is able to achieve each night. Biological rhythms influence adolescents to stay up later and wake up later in the morning. School districts across the country are taking notice of adolescent sleep research and delaying their start times to better match adolescents' biological rhythms. However, the majority of the schools in the United States continue to start earlier than the recommended 8:30am start time, including the school district targeted in this project. The purpose of this project was to collect data from administrators whose schools had undergone a delay in school start time on the barriers and facilitating factors they found during the implementation. This information was then shared with the local school district.

Antibiotic therapy has been proven to be vital for the treatment of life-threatening bacterial infections. Oral antibiotic therapy, however, results in unwanted side effects such as the intestinal flora destruction, allowing for the colonization of foreign bacteria. This phenomenon results in the occurrence of antibioticassociated diarrhea. Probiotic supplementation has been the choice adjunctive prophylaxis for this condition allowing for the bacterial adhesion of intestinal mucosal binding sites. Probiotic bacteria are, however, susceptible to the bactericidal effects of broad-spectrum antibiotics, resulting in many probiotic formulations being prescribed two hours after the ingestion of the antibiotic formulation. This is, however, not always adhered to, with many patients taking the antibiotic and probiotic concomitantly resulting in the destruction of the probiotic bacteria. This study provides for the design, development, characterization and evaluation of an oral delivery system for the concurrent administration of antibiotics and probiotics employing a dual release mechanism or ‘Dual-Biotic System’. The premise behind the development of this system is to allow for the concurrent administration of antibiotics and probiotics where the probiotic bacteria are only released two hours after the antibiotic, in which time the antibiotic would be absorbed into systemic circulation, preventing physical interaction between the systems and thus preventing bacterial destruction. Amoxicillin was chosen as the model antibiotic in this study due to its spectrum of activity and wide utilization in oral antibiotic therapy.

A laboratory scale delayed coking process was used to produce petrol precursors, diesel precursors, methane rich gas, green and calcined coke from five previously untested South African heavy petroleum residues. The ash content of the heavy petroleum residues was found to be detrimental to the microstructure of the green coke and Coefficient of Thermal Expansion (CTE) of the calcined coke. The sulphur content of the calcined cokes produced was found to be in-line with typical global anode grade cokes. De-ashing of the feedstock would be necessary to produce anode grade fillers for the aluminium industry. The local production of anode grade coke would serve to reduce imports and supply the aluminium smelters on the east coast of South Africa. The heavy petroleum residues (also known as heavy fuel oil) are currently used as bunker fuel in the shipping industry and are responsible for substantial air pollution. Delayed coking of these residues could extend the production of petrol and diesel per barrel of imported crude oil and reduce the effect on South Africa’s balance of payments deficit and impact the environment in a beneficial manner with respect to carbon dioxide and sulphur emissions. The research also evaluated the replacement of heavy fuel oil with marine diesel produced by delayed coking of the former. Marine diesel was found to emit less sulphur oxides and have a higher energy density per unit of carbon dioxide emitted. While seawater scrubbing of the heavy fuel oil would be more cost effective in reducing the sulphur oxide emissions, it would not contribute to carbon dioxide reductions. The research created a hypothetical scenario to determine the required value of Clean Development Mechanism credits for a marine diesel replacement, were shipping to be incorporated under the Kyoto Protocol in future

This dissertation presents a search for heavy, long-lived, neutral particles that decay to photons in proton anti-proton collisions with a center of mass energy of 1.96 TeV at the Collider Detector at Fermilab (CDF) experiment. Such particles are typical of models of Gauge Mediated Supersymmetry Breaking (GMSB). We select events with a single photon, missing transverse energy, and little other activity in the detector. We model the photon arrival time for Standard Model and non-collision sources using a data-driven method and consider photons which have a time of arrival at the detector which is significantly delayed relative to predictions. Using 6.3 fb^−1 of data collected from December 2004 to June 2010, we observe 322 events in the signal region compared to a background prediction of 287 ± 24 events. While the data are consistently above predictions, we report a model excess with a significance of 1.2 standard deviations from the null hypothesis.

With the increase in research on age-related decline in human cognitive capabilities has come an increased demand for a nonhuman cognitive aging model that controls for confounds in the human research, including education, socio-economic class, and language abilities. A nonhuman primate model of cognitive aging is particularly attractive given the similarities in physiology and behavior between nonhuman primates and humans. The rhesus macaque has proven to be a highly effective model of human aging, but apes, the closest genetic relatives to humans, are virtually unstudied. Only three studies have examined age-related changes in cognitive abilities in apes, and all three studies were conducted using tasks that have had relatively little success in revealing age-related performance decline in monkeys. Sixteen gorillas housed at Zoo Atlanta and Disneys Animal Kingdom underwent five experiments to determine the effects of age, sex, and previous research experience on performance. Testing occurred in a modified Wisconsin General Test Apparatus using the delayed response paradigm. When delay intervals were increased from zero to 90 seconds performance decreased across all subjects. However, there was no univariate effect of age, sex, or experience on performance. Similarly, when the number of potential choice sites was increased from two to four there was a decrease in performance, but again there was no univariate effect of age, sex, or experience. However, older subjects were more likely to have a response bias and choose a single site across all tasks, irrespective of where the reward was located. This effect was more pronounced in inexperienced subjects. As a result, age does not appear to affect performance accuracy in the delayed response task in gorillas, but there may be an effect on response rigidity. Given the shortcomings of the delayed response task in simple cognitive studies with nonhuman primates, further research on cognitive aging in gorillas should utilize a research naïve population and use an experimental protocol that is titrated based on individual responses. This will allow the delay interval to be gradually increased to a point where age-related differences may be apparent.

Dialyzable leucocytic extracts (Transfer Factor) were prepared from guinea pigs, rabbits, dogs and cattle sensitized to tuberculin, from cattle and dogs reactive to coccidioidin and from cattle sensitized to 2,4 dinitrochlorobenzene and Pasteurella multocida. These Transfer Factor (TF) preparations were used in intra- and interspecies transfers of delayed hypersensitivity (DH) and cellular immunity (CMI) in guinea pigs, rabbits, dogs, cattle and humans. Various doses and routes of administration were employed. Success of transfer was based upon dermal skin reactivity and/or clinical improvement. Our results suggest the following: (a) interspecies transfer of DH is effective with a variety of species, (b) oral administration of TF is effective and (c) cattle are effective donors of TF for use in humans and other animals because of potential quantity and strong potency of transfer material.

This thesis considers the design of distributed state and output feedback control algorithms for linear multi-agent systems with performance guarantees in the presence of delays. The multi-agent systems considered are assumed to exchange relative information over an information network. As a first contribution, a novel distributed state feedback control design method with a sub-optimal LQR performance is developed for a network of multiple agents. For the control design process, it is assumed that the exchange of relative information is instantaneous. A stability analysis of the proposed control law is performed by incorporating delays in relative information to ascertain the maximum possible delay that can be accommodated by the communication network. Subsequently, the assumption of the exchange of instantaneous relative information in the control design process is relaxed and the relative information is assumed to be delayed. The system is then represented as a time-delay system. Distributed state feedback control synthesis methods are then developed for the system with a certain level of LQR performance. In the above contributions, the time delay analysis and the development of delay based control methods, it is implicitly assumed that delays are detrimental to achieving cooperative tasks for a multi-agent system. Subsequently, positive effects of delays in communication of relative information are explored. For this a network of vehicles described by double integrator dynamics, which cannot be stabilized by static output feedback without delays, is considered. A novel control design method to achieve exponential stabilization of such a multi-agent system by static output feedback using delayed relative information is developed. Conclusions are drawn from the results of the research presented in this thesis and a few directions for future work are identified.

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