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Limited fossil fuel resources and the environmental impacts of climate change are motivating the development of sustainable processes for the production of fuels and chemicals from renewable resources. The development of alternative energy sources, such as biofuels, will strengthen energy security and reduce dependence on fossil fuels. n-butanol is a biofuel and platform chemical. n-butanol is an advanced fuel with high energy content, compatible with existing infrastructure. Here the ability of microorganisms to use renewable resources for biofuel synthesis is exploited. In this work use of the thermophilic bacterium Geobacillus thermoglucosidasius is explored for the production of n-butanol. Geobacillus is considered a promising industrial process organism due to its high optimum growth temperature and ability to assimilate various substrates including both hexose and pentose sugars. As a relatively novel process organism, first the development of molecular tools was required to enable subsequent engineering of the host metabolism. Here four reporter assays were developed, three of which can be used simultaneously, providing for extensive analysis of qualitative and quantitative gene expression within the cell. A range of promoters and RBS’ were screened. Extension of the Geobacillus vector series, pMTL60000, with new component parts for each module enabled co-transformation of two plasmids into G. thermoglucosidasius. The molecular tools developed were then applied in Geobacillus metabolic engineering work, with the aim of producing the target molecule n-butanol. Initially a CoA dependent n-butanol pathway, based on naturally occurring production by ABE fermentation, was considered. Following introduction of the pathway further metabolic engineering was employed to improve pathway flux, creating a driving force through the pathway and increasing the substrate pool. Production of 0.137 mM (10.166 mg/l) n-butanol demonstrated proof of concept. Next, the use of genes native to Geobacillus were investigated for improved enzyme compatibility. This approach did not generate n-butanol here. Finally a CoA independent pathway utilising the host’s native fatty acid biosynthesis pathway was considered. Using this approach, butyric acid was produced. Butyric acid can subsequently be further converted to n-butanol however this was not demonstrated here. In addition to metabolite pathway introduction, host strain engineering was carried out with the aim of adaptation towards industrially desired properties. Directed evolution resulted in selection of a strain with an increased n-butanol tolerance of 2.5% (v/v). Such modifications resulted in an improved process organism for biotechnological application. This work provides the first reported production of n-butanol in thermophilic and aerobic conditions. Multiple approaches to n-butanol production are evaluated here. Use of heterologous and native genes are considered. Both CoA and ACP dependent pathways were introduced. Each approach presented advantages and drawbacks. A system compatible for use in Geobacillus has demonstrated proof of concept n-butanol production. Further development is required to increase production to industrially feasible quantities.

This dissertation addresses the question of how suburban school district leaders in one large Midwestern school district respond to increasing student poverty. The purpose of this study was to determine how suburban school district leaders respond to increasing student poverty in their decision making and actions. Data for this study came from one large suburban school district in Kansas. For decades, the district was known traditionally for wealthy areas and families as well as extremely high student achievement. Over a 15 year period, student poverty grew significantly. Free and reduced student populations grew from single digit percentages to nearly 40% of the district enrollment. A doubling of students' need occurred every four years with poverty forecasted to continually grow. As a result, this district was a prime source of study. Current literature investigating suburban school district leaders' responses to the growing student poverty is sparse. Therefore, literature reviewed for this study included urban district leaders' responses to student poverty. Studies revealed urban school districts to possess similar demographic changes to suburban settings at the onset of growing poverty. Thus, urban studies contributed to the investigations of this suburban study. Out-of-school factors which poverty brings into school settings are also similar in urban and suburban settings. Housing and resources needed to manage poverty's out-of-school factors were common to both settings. In this suburban district studied, these factors evolved as part of leaders' responses. Housing changed in the suburban district and students were less prepared for learning due to factors in their homes. Varied recognition of increasing student poverty contributed to purposeful versus lack luster responses. Leaders' efforts to respond to increasing student poverty were occasionally founded in research; yet, others were implemented with no researched-based decision-making. Literature describing organizational theory and leaders' decision-making was also utilized in this study. As poverty was recognized as a phenomenon needing district leaders' planning, greater effectiveness in decision-making was gained through use of multiple frameworks. Prior, suburban leaders hadn't been pushed to reframe their thinking due to homogenous populations. One-size fits all may have been effective before student diversity became present. Multiframed thinking evolved over time as leaders moved past singular framed decisions closely related to their own roles. Using in-depth qualitative data from interviews along with quantitative data, this study sheds light on decision-making and actions of suburban district leaders as they responded to increasing student poverty. Key findings indicated initial decisions were made with little recognition to increasing poverty. Initially, decision making was made through a political framework. Therefore, initial decisions were made out of compliance versus decision-making with intent to respond to student poverty. As recognition of student poverty grew, true intentions to respond to increasing student poverty surfaced. Key areas were uncovered as foci in district leaders' responses: reinvestments in neighborhoods, improving programming, early intervention, and teacher professional development. Additionally, lessons learned for the future were uncovered in suburban district leaders' responses to increasing student poverty. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]