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Genomic analysis and physiological experiments conducted on the lignocellulosic biomass degrading bacterium C. phytofermentans, indicates that it can degrade and utilize a wide-range of carbohydrates as possible growth substrates. Previous experiments characterized gene expression using custom whole genome oligonucleotide microarrays. The results indicated that C. phytofermentans utilizes ATP-binding cassette (ABC) transporters for carbohydrate uptake and does not use the sole phosphoenolpyruvate-phosphotransferase system (PTS) for any of the tested substrates.Distinct sets of Carbohydrate Active Enzymes (CAZy) genes were also up-regulated on specific substrates indicative of C. phytofermentans ability to selectively degrade lignocellulosic biomass. We also identified a highly expressed cluster of genes which includes seven extracellular glycoside hydrolases and two ABC transporters with unknown specificity on a number of substrates. These results lead to the hypothesis that when grown on plant biomass, C. phytofermentansis capable of degrading and transporting all major carbohydrate components of lignocellulose biomass. To test this, C. phytofermentans was grown on three different lignocellulosic biomass substrates (Brachypodium distachyon, cornstover, and switchgrass). Gene expression and HPLC analysis indicated that C. phytofermentans is utilizing multiple substrates with multiple sugar ABC transporter clusters, glycoside hydrolases, and sugar utilization pathways being expressed. To further test this,the sugar utilization pattern for C. phytofermentans was investigated. Growth studies were performed on individual saccaharides (glucose, cellobiose, xylose, and fucose) as well as combinations of all these sugars. From these studies we determined that C. phytofermentans does not show a characteristic diauxic shift indicative of preferential sugar utilization or carbon catabolite repression (CCR). This result was supported further by HPLC analysis indicating that co-utilization of sugars was occurring, however their were differences in the rates of consumption. Expression analysis of dual sugar combinations of glucose/cellobiose, glucose/xylose, and glucose/fucose also shows that genes involved in the transport and utilization of each sugar are expressed. We also noted glucose repression of some of the glyocside hydrolases which are normally expressed on xylose and fucose. The results from this study indicate that C. phytofermentans can utilize multiple sugars simultaneously.

Woolgathering aims to speculate around ways to reduce the wasteof wool and how wool can catalyze the regeneration of ruralvillages in the north of Sweden. In Sweden today, we producearound 1000 metric tons of wool per year, yet only about half of it isused. This is due to its varied quality and a lack of political support,economic incentive and a low demand on global and nationalmarkets causing a loss of knowledge in wool management andfailing value chains. Modern monocultural agriculture has phasedout traditional sheep breeds and vital semi-natural pastures whichhas had detrimental effects on biodiversity, cultural heritage andland ownership. Björkå, a rural village Västernorrland, has had adwindling population and is in need of regeneration in order toalleviate symptoms of rural neglect. Inspired by the architecutralaccpuncture employed in Songyang and the Brown sugar factoryin Xing village as well as the cooperative management of thefarms in Marinaleda, and a visits to Björkå and one of the manylocal sheep farms, I identified wool as a potential catalyst forthis development along with a series of devices to be employedin a rural regeneration strategy: rural-urban links, tourism, localeconomy, cultural heritage, industry and nature. The woolgathering strategy, like the darning of woolensocks, introduces these devices along with local and regionalactors as threads that feed into the fabric of Björkå aiming torestore its integrity. There is a focus on locally controlled industrywhere economical profits feed back into the community but alsoon collaboration between local and national wool actors. Thecentral core of the strategy merges the 6 devices with the 5 actors. The different threads and wool programmes merge andform new associations, or become integrated into new (virtualand physical) networks that expand well beyond the rural locality. With wool as the catalyst, the strategy can start to mend thegaps in the territory, reconnecting links to endogenous networkswithin the wool industry and exogenous networks between actorsand create economic viability for sheep farmers locally and across Norrland.

Cognitive Radio Network (CRN) is an emerging paradigm that makes use of Dynamic Spectrum Access (DSA) to communicate opportunistically, in the un-licensed Industrial, Scientific and Medical bands or frequency bands otherwise licensed to incumbent users such as TV broadcast. Interest in the development of CRNs is because of severe under-utilization of spectrum bands by the incumbent Primary Users (PUs) that have the license to use them coupled with an ever-increasing demand for unlicensed spectrum for a variety of new mobile and wireless applications. The essence of Cognitive Radio (CR) operation is the cooperative and opportunistic utilization of licensed spectrum bands by the Secondary Users (SUs) that collectively form the CRN without causing any interference to PUs' communications. CRN operation is characterized by factors such as network-wide quiet periods for cooperative spectrum sensing, opportunistic/dynamic spectrum access and non-deterministic operation of PUs. These factors can have a devastating impact on the overall throughput and can significantly increase the control overheads. Therefore, to support the same level of QoS as traditional wireless access technologies, very closer interaction is required between layers of the protocol stack. Opportunistic spectrum utilization without causing interference to the PUs is only possible if the SUs periodically sense the spectrum for the presence of PUs' signal. To minimize the effects of hardware capabilities, terrain features and PUs' transmission ranges, DSA is undertaken in a collaborative manner where SUs periodically carry out spectrum sensing in their respective geographical locations. Collaborative spectrum sensing has numerous security loopholes and can be favorable to malicious nodes in the network that may exploit vulnerabilities associated with DSA such as launching a spectrum sensing data falsification (SSDF) attack. Some CRN standards such as the IEEE 802.22 wireless regional area network employ a two-stage quiet period mechanism based on a mandatory Fast Sensing and an optional Fine Sensing stage for DSA. This arrangement is meant to strike a balance between the conflicting goals of proper protection of incumbent PUs' signals and optimum QoS for SUs so that only as much time is spent for spectrum sensing as needed. Malicious nodes in the CRN however, can take advantage of the two-stage spectrum sensing mechanism to launch smart denial of service (DoS) jamming attacks on CRNs during the fast sensing stage. Coexistence protocols enable collocated CRNs to contend for and share the available spectrum. However, most coexistence protocols do not take into consideration the fact that channels of the available spectrum can be heterogeneous in the sense that they can vary in their characteristics and quality such as SNR or bandwidth. Without any mechanism to enforce fairness in accessing varying quality channels, ensuring coexistence with minimal contention and efficient spectrum utilization for CRNs is likely to become a very difficult task. The cooperative and opportunistic nature of communication has many challenges associated with CRNs' operation. In view of the challenges described above, this dissertation presents solutions including cross-layer approaches, reputation system, optimization and game theoretic approaches to handle (1) degradation in TCP's throughput resulting from packet losses and disruptions in spectrum availability due non-deterministic use of spectrum by the PUs (2) presence of malicious SUs in the CRN that may launch various attacks on CRNs' including SSDF and jamming and (3) sharing of heterogeneous spectrum resources among collocated CRNs without a centralized mechanism to enforce cooperation among otherwise non-cooperative CRNs

Stress has been linked to increased illness in several biologically based studies. In contrast, only a limited number of studies have assessed psychological variables related to stress, with self-efficacy and locus of control serving as potentially important variables. Thus, the current study investigated the mediating effects of self-efficacy and locus of control in the relationship between stress, psychological and physical symptoms, and the utilization of health services in college students. Results suggested that stress was correlated positively with symptoms. External locus of control was correlated positively with stress and symptoms, and self-efficacy was correlated negatively with stress and symptoms. Further, structural equation modeling was used to test two separate models. The first model examined the relationships between stress and symptoms and between symptoms and utilization of health services. Although the path coefficients suggested that there were direct relationships, the data did not adequately fit this model. The second model examined the potential mediational effects of locus of control and self-efficacy on the relationship between stress and symptoms. The path coefficients for the second model were consistent with a mediation effect for locus of control in the relationship between stress and symptoms; however, when this model was tested for full mediation, the data did not fit the model. These results highlight the importance of having future studies examine and identify potential mediators of the stress and illness link. Implications for reducing health care costs and promoting better mental and physical health are discussed.

In recent years, there has been increased focus on rural and Appalachian health because of disparate chronic health outcomes when compared to the rest of the US. Appalachia, a subsection of the US, has even worse health outcomes related to chronic diseases. Although Appalachia is its own unique region, there is significant overlap with rural areas in terms of shared cultural characteristics (e.g., strong sense of community, distrust in outsiders, lack of trust in traditional medicine, and strong Christian religious affiliations and faith in God), limited access to healthcare services, and disparate health outcomes. The research presented in this dissertation is significant because it provides insight into and compares healthcare utilization rates in women in Appalachia and surrounding areas. Study 1: In addition to racial discrimination, Black Appalachian women often face other obstacles involving other types of negative interpersonal experiences when seeking healthcare. Despite these known disparities, Black women are frequently underrepresented in Appalachian health research. This study investigated healthcare experiences for sixteen Black Appalachian women using semi-structured interviews to identify and subsequently address ways to eliminate barriers to care. Interview questions utilized the theory of intersectionality and the Social Ecological Model to create a framework to describe the complexity of healthcare utilization and barriers to care while providing context into each participant's background and lived experience. Interview questions explored four topics: 1) barriers to medical care; 2) social support; 3) ideal and actual healthcare experiences; and 4) desired changes to improve quality of care. We used an inductive analysis process to create a robust thematic coding schema, organizing responses into 60 total themes and 141 codes, and reported the most frequent. Our results explore the ways in which one's intersectional identity as a Black Appalachian woman affects interpersonal interactions and experiences when engaging with the healthcare system. Participants frequently reported barriers related to scheduling conflicts and delays, experiences with rushed appointments and inhospitable providers and support staff, and desires for accurate collection of medical information. Participant responses often emphasized difficulties with the organization of the medical system, revealing specific areas for future intervention to improve quality of care for Black Appalachian women. Study 2: Use of the emergency department (ED) for low acuity conditions (e.g., back pain, dental pain, sore throat) and primary care places an additional strain on ED staff and resources, while increasing waiting and treatment times for high acuity patients. Factors such as race, gender, and insurance type have a strong association with the likelihood of a patient using the ED for a low acuity concern. Women are more likely to utilize healthcare services, which also holds true in the context of the ED. Using a sample of adult women from Virginia, West Virginia, Tennessee, North Carolina, and Kentucky, I investigated which demographic factors, age, race, geographic location (metro, nonmetro, rural), employment, and insurance coverage, affect a patient's likelihood to visit the ED for a low acuity condition within a southwestern Virginia hospital system. Log-binomial regression was used to estimate unadjusted and adjusted prevalence ratios of acuity level by race, age, rurality level, employment, and insurance type with corresponding 95% CIs. Our sample included 28,222 female patients who visited the ED between January 1, 2021 and September 30, 2022. Low acuity visits accounted for 15.9% (n=4,485) of visits during the timeframe. In summary, our results suggest that older age and location in non-metro area are the most salient factors contributing to a higher likelihood of low acuity ED visits among women. Race, a primary variable of interest, did not have the relationship to acuity that was expected based on previous literature; Black women patients were less likely to have a low acuity visit than white women patients. During our study period, overall number of visits remained steady, while there was an increase in proportion of low acuity visits. Further research is needed into the underlying causes to more definitively explain this increase. / Doctor of Philosophy / In recent years, there has been increased focus on rural and Appalachian health because of disparate chronic health outcomes when compared to the rest of the US. Appalachia, a subsection of the US, has even worse health outcomes related to chronic diseases. Although Appalachia is its own unique region, there is significant overlap with rural areas in terms of shared cultural characteristics (e.g. strong sense of community, distrust in outsiders, lack of trust in traditional medicine, and strong Christian religious affiliations and faith in God), limited access to healthcare services, and disparate health outcomes. Black/African Americans are another population with higher rates of chronic disease and poorer health outcomes compared to their white and Latinx peers. The combination of poorer health outcomes and higher rates of chronic disease negatively impacts life expectancy and quality of life. One driving factor in these poor health outcomes across all of these groups is low rates of healthcare utilization, whether due to decreased access (as is the case for many rural populations), or other as of yet unidentified challenges. Although literature exists about rural health outcomes, Appalachian health outcomes, and health outcomes focusing on Black women, there is very limited literature that examines the intersectional impact of these characteristics on health. Health disparity research in this region does not currently stratify differences in outcomes by both race and gender, which prevents a detailed analysis of the full extent of the gap in health outcomes. This research presented in this dissertation is significant because it provides insight into and compares healthcare utilization rates in women in Appalachia and surrounding areas across the lifespan. Knowing the contextual factors influencing healthcare seeking behaviors and utilization is the first step to designing effective interventions that improve women's access to care. Interventions need to be intentionally designed to consider, and ultimately, shift medical care and community attitudes to decrease health disparities in Appalachia. To successfully decrease health disparities, it is necessary to consider all of a patient's identities or characteristics. The same contextual factors that affect their healthcare utilization can also impact their care experience.

Responses to a web-based survey following Hurricane Katrina were evaluated. The 3,140 university student respondents were separated into impact groups based on evacuation experience: high-impact (student evacuated), moderate-impact (friend/family evacuated), and low-impact (neither student nor friends or family evacuated). Students’ responses to items evaluating service utilization, services desired, and psychological distress were examined by gender, race, and impact group. Female students rated services as more supportive, and reported a greater desire for services not provided by the university, compared to male students. Compared to Caucasian students, African American students viewed services as more supportive and desired services not already provided by the university. Students in the high-impact group scored higher than the other impact groups on measures assessing symptoms of psychological distress. Overall, the results may be used by universities and other organizations to implement future programs and policies for responding to natural disasters.