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For robots to successfully be deployed as human assistants in a variety of applications, it is critical that the robots' controllers and planners are designed with the considerations of both the robots' and humans' abilities and needs. In space applications, where energy is a finite and limiting resource in missions, it may prove necessary to exploit the energy storing-component of series elastic actuators to meet the efficiency needs, while operating in harsh and varied environments. In human-occupied workplaces, robots can only provide the needed support to humans if the robot controller can properly reason about and react to humans' requirements and capabilities. This thesis presents and assesses strategies to address these kinds of scenarios. In Chapter 2, we present a trajectory optimization scheme based on sequential linear programming to leverage the energy-storing capabilities of series elastic actuators for high-performance tasks. We discuss the current limitations in optimization strategies for series elastic actuated robots. One of the difficulties of this planning problem is respecting all relevant, low-level actuator constraints and handling system nonlinearities in a computationally efficient manner. Our simulation and hardware experiments demonstrate the leveraging of compliance for faster motions as compared to those that are achieved by the compliant systems' rigid counterparts. Chapter 3 addresses the need for reactive synthesis to be employed to automatically devise human-aware robot controllers for scenarios in which humans and robots continuously collaborate. Through this approach, it is possible to synthesize high-level control policies that are formally guaranteed to meet human requirements. We present a case study in which a robot seeks to deliver work to a human so that the human is productive, but not stressed by her work backlog. We demonstrate the achievement of a human productivity-informed controller using a mobile manipulator robot that picks up and delivers work based on work backlog. One of the challenges of this problem is devising human productivity models that are practical and accurate. We explore a toy scenario in the hope that this research will introduce methodologies that can be generalized for more practical cases

Alcohol Use Disorders (AUDs) have devastating economic, mortality, and public health implications on society. Repeated cycles of alcohol intoxication and abstinence are known to induce neuroplastic alterations in specific brain regions, alterations which in turn trigger and sustain excessive alcohol drinking. The Bed Nucleus of the Stria Terminalis (BNST) has been proposed as a critical brain site for neuroadaptations induced by chronic alcohol. The Pituitary Adenylate-Cyclase Activating Polypeptide (PACAP) system highly expressed in the BNST, has been proposed to be a master regulator of the stress response. These experiments aimed to investigate the role of the PACAP system of the BNST in alcohol drinking. Using a two-bottle choice chronic intermittent ethanol paradigm, we demonstrated that excessive intermittent alcohol consumption causes a marked increase in PACAP immunoreactivity in the BNST of mice. In addition, we observed a significant higher PACAP expression in the BNST of female, compared to male mice. These data lay the foundation for more extensive studies which may lead to the identification of a neuropeptide system with a critical role in heavy alcohol drinking. A deeper understanding of the specific neuroadaptations produced by chronic alcohol will be essential for the discovery of novel therapeutic agents to alleviate alcoholism.

The prairie pothole region (PPR) extends over 700,000 km2 and contains an estimated 2.6 million wetlands. Wetlands in the PPR comprise a uniquely productive ecosystem in the Great Plains region of the United States and Canada. Agriculture has dramatically altered the landscape in the PPR, transforming prairie into rangeland and draining vast swaths of wetlands. The remaining `pothole’ wetlands are significantly impacted by nutrient inputs and non-point source pesticide pollution. Recent studies have demonstrated that reduced sulfur species (e.g., bisulfide, polysulfides) in wetland pore water can significantly enhance the degradation of chloroacetanilide and dinitroaniline compounds in PPR wetlands. In this study the abiotic transformations of the organophosphate compounds chlorpyrifos (CP) and chlorpyrifos-methyl (CPM) were analyzed in PPR wetland pore waters. Chlorpyrifos-methyl reacted significantly faster (up to 4 times) in pore water with reduced sulfur species relative to hydrolysis. No rate enhancement was observed in the transformation of chlorpyrifos in pore water with reduced sulfur species, most likely due to partitioning to dissolved organic matter (DOM) inhibiting the reaction. Significant degradation rate reduction was observed for chlorpyrifos in pore water with high concentrations of DOM. Rate enhancement due to other reactive species (e.g., organo-sulfur compounds) in pore water was minor for both compounds relative to the influence of bisulfide and DOM. The results of this study demonstrate partitioning to organic matter may be more significant in determining the transformation kinetics of hydrophobic compounds than the presence of reactive species in the environment.

This is a concurrent, mixed methods study of the impacts of Austin, Texas’s cultural plan, CreateAustin. In the study, trend analysis and a t-test were used to examine variables before and after the cultural plan was in place. At the same time, interviews with cultural planners were used to uncover other effects. My research addresses a gap in the literature between understanding the desired and actual outcomes of a cultural plan. Cultural plans are being developed by many communities in an effort to attract creative workers but they are rarely evaluated. Evaluation using a mixed methods approach is necessary to capture all the outcomes of a cultural plan, rather than the limited scope of impacts that are captured by qualitative or quantitative analyses alone. My analysis of the quantitative variables showed some significant differences between when the plan was in place and the years prior to its creation. Interviews with key stakeholders revealed the formation of new networks as a powerful outcome of the planning process. The results allowed me to gauge the overall impact of CreateAustin and make some observations about the cultural planning process in general, as well as uncover new directions for future research.

As the sun sets on the industrial age, cities all over the world are preparing themselves to be competitive in the new information age. In the United States of America, cities are eager to differentiate themselves from each other in order to attract residents, businesses and tourists. The city is expected to offer some cohesive vision of this atmosphere in order to make it attractive to tourists, residents and businesses. An increasingly popular way for a city to stay relevant is to develop a cultural plan to foster a vibrant scene. A cultural plan provides an overview of the cultural amenities that a city currently possesses, assesses the needs of the city and the community, and produces a roadmap for future cultural developments for the purpose of enriching the lives of its citizens, making the city stand out to tourists and businesses, and encouraging economic development. Cultural plans are often undertaken with different motives, varying levels of preparation and understanding, uneven implementation, and rare evaluation. There is a need for concise and compelling research on the subject that policy makers can access and utilize in their cultural planning processes. The absence of evaluative criteria and research makes it difficult to know the best way to undertake new cultural plans. Evaluation of cultural plans allows cities to determine if their plan was successful and if public resources were properly utilized. Using research done on by The Urban Institute on Cultural Vitality Indicators and the evaluation of the European Capitals of Culture program forms an analytical framework by which to evaluate cultural plans. There are many good reasons for studying the cultural planning process in the US. Strong cultural plans will benefit city economies. Cultural plans can have a positive effect on the community and on urban regeneration. It is a responsible use of public money to make cultural plans realistic and executable. Better understanding of the cultural planning process will help other cities develop plans of their own. This thesis uses data collection and analysis to understand the cultural planning processes better and inform longitudinal case studies of Austin, TX and Columbus, OH. The goal of the study is to deepen understanding of what criteria are most important to the planning process and how it can be best utilized before, during, and after the generation of a cultural plan. Clearer understanding of this information will lead to better implementation of cultural plans, a more vibrant urban environment, and a better use of public resources.