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Mental health outcomes of rural versus urban areas as income to poverty ratios and educational attainment increase.
No full textThe prevalence of depression and anxiety is on the rise in America. Poverty-rates are growing nationwide but more in Rural areas than in Urban. People who have lower income and lower education tend to have worse mental health, exacerbated by poverty rates. This study examines how income and education’s association with mental health and how it differs by urban vs. rural residence, to do this I will fill the gap in the literature by examining the difference of rural and urban populations as income to poverty ratio increases and educational attainment increases to view how these resources can lead to changes in mental health, more specifically depression symptoms and anxiety. Results from weighted OLS regressions using 2022 NHIS data (N= 24,177) indicate higher income to poverty ratio and higher educational attainment both decrease anxiety and depression symptoms, but that this association is stronger in rural populations than in urban populations
Parasitism and more in the fossil record : constraining and contextualizing the record of crustacean trace-producing symbionts.
No full textBiotic interactions are a critical element of ecology but remain a considerable gap in knowledge of the fossil record and the history of life on earth. Broadening our understanding of biotic interactions in the fossil record will be critical in resolving ecological and evolutionary dynamics across scales, and in modeling long-term ecosystem responses to shifting environments. Although understanding these trends is critical, broad, intensive research effort will be necessary to resolve biotic interactions outside of predation in well-resolved fossil records and lineages.
Here, we present three studies investigating patterns in the preservation and occurrence of fossil traces of biotic interactions of crustaceans. First, we present the first use of finite element analysis (FEA) for the non-destructive preservation modeling of a fossil parasitic swelling, Kanthyloma crusta. We find that the parasitic swellings responded with significantly higher peak stress than healthy regions from the same applied forces, suggesting a shape-related decrease in fossil preservation potential for Kanthyloma crusta. Second, we use experimental taphonomy to investigate the post-mortem preservation of the blue crab, Callinectes sapidus, with and without infestation by the rhizocephalan barnacle parasite Loxothylacus texanus. We find minimal differences in the rate and pattern of degradation between specimens, suggesting no impact on the preservation potential of host Callinectes due to the presence of the parasite. Finally, we survey bivalves and gastropods for the acrothoracican barnacle boring Rogerella in two extensive collections which primarily represent Cenozoic fossil assemblages from the east and west coasts of North America. We find significantly greater size and parasite load among specimens with Rogerella from the east coast of North America as compared to the West Coast. We highlight the necessity of investigating biotic interactions in the fossil record to contribute to our understanding of ongoing ecosystem shifts and suggest avenues for future research. We also advocate for improved sampling, availability, and organization of fossil-associated trace data to facilitate future research
Tradition richness : a theory of campus traditions and culture.
No full textCampus traditions are a common feature on college and university campuses across the United States; however, there is little literature examining these cultural features. Though there seems to a skepticism around traditions, Christian colleges and universities offer a positive vision for what campus traditions can be. Operating from the premises that deep-seated habits are spiritually formative and that traditions—when done well—function as liturgies of celebration, it is important to understand how traditions relate to campus culture in order for Christian institutions to engage student in such formation. As such, this study sought to describe the nature and intensity of the relationship between tradition and culture by presenting an interdisciplinary theory of tradition richness, approaching traditions as a form of interaction ritual. This theory is then clarified through a collective case study of five governing members of the Council for Christian Colleges & Universities. The findings from this study reiterated existent literature on campus traditions and rituals but adds clarification and expansion on elements to the theory presented. The study points to the importance of structural elements for traditions to exist in abundance on a campus and functional elements that allow traditions to permeate the culture and perpetuate so as to in turn structure culture. Further clarification is also presented on the networks of memories and symbols resultant from traditions that are connected to emotional energy and group unity and identity, which can exist at multiple functional levels of a campus community and so structure life and culture
Civic engagement among emerging adults : evidence from the panel survey of income dynamics.
No full textThis dissertation seeks to evaluate the state of emerging adult civic engagement within the United States. Civic engagement is an important facet of society as it is the combination of individual and collective efforts aimed towards resolving issues of public concern. Emerging adults are a unique population as they are developing their own identity within society as they transition from the original family unit they grew up in. While largely independent, emerging adults are still engaging with their original family unit through economic and social means. Using the Panel Study of Income Dynamics (PSID) Transition to Adulthood Supplement, I seek to evaluate the impact family composition, familial financial support, perceived time pressure, and class-of-origins has on civic engagement. Utilizing quantitative methods I found evidence to support positive relationships between being raised in a dual-headed household and higher parental class status on increases in emerging adult civic engagement. The class-of-origins of the emerging adults directly impacts the accessibility of civic opportunities, cost of participating, and the culture around civic engagement for emerging adults
Effective loop quantization of black holes : a comparative analysis of quantization schemes.
No full textLoop quantization of spherically symmetric black hole (BH) spacetimes has quantization ambiguities stemming from the choices (schemes) of the two polymerization parameters that characterize quantum corrections in effective loop quantum gravity (LQG). In this dissertation we systematically carry out the following investigations in the framework of the Kantowski-Sachs (KS) gauge: (a) We first study a top-down quantization that is derived from full LQG. The semi-classical approximation of this model resolves the central BH singularity and replaces it with a transition surface. The spacetime to the future of the transition surface depends on the ratio of two spin numbers involved in the model. We also find the inverse volume corrections become important only when the radius of the two-sphere is of the Planck size and are hence negligible for macroscopic BHs. (b) We study a quantization scheme recently proposed, where the polymerization parameters are the Dirac observables of the four-dimensional phase space of Ashtekar’s variables. The model predicts a white hole horizon beyond the transition surface which replaces the singularity. However, the spacetime to the future of the transition surface is unlike any of the loop quantum black holes (LQBHs) studied so far. In particular, the location of the maximal curvatures is different from the location of the transition surface that has the minimal area. (c) We systematically study all the solutions of LQBHs with constant polymerization parameters and find the classical singularity is always resolved. Additionally, assuming the black and white hole masses are equal, we identify a whole family of solutions that share all the desired properties of the Ashtekar, Olmedo and Singh model. (d) Finally, we extend the studies carried out in (c) to the Schwarzschild BH coupled with a cosmological constant (Λ) and show that for Λ > 0 there can be an appearance of large quantum effects at low curvatures. These effects can manifest as an additional black hole horizon. Although central singularity is always resolved, these limitations demonstrate the incompatibility of the KS gauge and schemes with constant polymerization parameters when a positive cosmological constant is present
Problematizing the present and possibilizing the future : designing a critical historiography "history of the present" framework for social studies education.
No full textThis dissertation studied the construction and implementation of a ‘history of the present’ curricular framework for critical historical analysis in social studies classrooms using a Design-Based Research methodology with a Constructivist Grounded Theory approach and an embedded multiple case study. By drawing on various approaches to critical historiography, including genealogy and historical materialism, this framework offers teachers suggestions to critically (re)consider how they approach Centering, Sourcing, Scaling, and Narrativizing within their curriculum and engage students in history as an interpretive field with a diversity of epistemological approaches and theoretical underpinnings. Approaching history in this way is intended to support teachers (and students) in interrogating and problematizing historical and contemporary antagonisms to develop a potentially transformative possibilizing stance toward future social action. This study includes findings from the development of this curricular framework and its initial implementation in K-12 classrooms by a design team of veteran social studies educators and has significant implications for teacher education and history classrooms
Finite element-based failure analysis of composite laminates with non-destructive feature quantification.
No full textCarbon fiber reinforced polymers (CFRP) have become a mainstream material in the manufacturing process of industries from almost every sector - automotive, aerospace, energy, medical, sports and entertainment. While they are often preferred because of their superior material properties over traditional materials, their complex structural composition makes it very difficult to characterize and predict the failure process while they are in operation. This research experimentally investigates the failure mechanism of CFRP manufactured under three different loading modes: failure onset for a planar loading condition, delamination for a mixed mode static and dynamic bending/shear loading, and progressive failure of a part caused by improper drilling with complex initial damage; and generates predictive models through novel implementations of the finite element method that are experimentally validated. The first case uses the uncertainty in the ply orientation based on measurements from an ultrasound inspection to determine the probability of failure based on an extension of the classical laminate theory and the Tsai-Wu failure criteria. The probability of failure is determined by Monte Carlo Simulation and compared to the Mean Value First Order Second Moment method (MVFOSM), followed by a validation through a Monte Carlo simulation in the finite element environment. The probability of failure is quantified using a Cumulative Density Function (CDF) to decide whether a composite panel is safe for operation or needs replacement. The second case analyzes the delamination as a failure mode for L-shaped composite laminates. The influence of the stacking sequence in delamination growth is investigated to offer a better design solution for L-shaped composite panels subjected to bending stress. The delamination is characterized by micro computed tomography as a nondestructive mode of inspection for both static and dynamic loading conditions. The developed finite element model to predict the progressive failure response is validated through experimental data and fractographic images. Lastly, a three-dimensional static tensile testing case for a drilling induced damaged carbon fiber laminate is considered for progressive failure analysis. A novel method is developed to identify and quantify the inherent drilling induced damage in each ply interface using ultrasound. The damaged region for multiple samples is designed and simulated in the finite element environment to establish a correlation between the extent of the damage and the ultimate failure strain of the samples which is subsequently compared to experimental findings. This approach holds promise for the safety of manufactured structures by reducing uncertainty and enhancing accuracy in assessing load-bearing capabilities through the coupling of ultrasonically characterized damage zones with finite element simulations. This comprehensive failure analysis provides a valuable insight into the damage identification process, failure mechanism and practical implications for industry application
"Dishes and laundry" : a one act musical.
No full textDishes and Laundry explores the complexities of OCD and effects on both parties of a relationship. A widely misunderstood and misrepresented disorder, OCD is often a subject of comedy, appropriation, and insult. The work aims to shed light on the true, debilitating nature of this disorder, simultaneously advocating and offering encouragement to those suffering. The narrative follows Morgan and Carter discovering Morgan's OCD, struggling with its symptoms, and resolving to fight for their relationship despite the difficulties they face. Inspired by a wide range of musical theatre styles, OCD is explored not only in the narrative but in the music as well, with recurrence as the most prominent mode of representation. Though the work is currently confined to one act, the compositional and editorial process, has revealed the possibility, and near necessity, of expansion to a two-act musical
Voluntary wheel running mitigates hyperglycemia-induced depressive-like behavior and increases hippocampal BDNF levels in male mice.
No full textDiabetes is associated with an increased risk for depression. Emerging data suggests this effect is partly mediated by hyperglycemia increasing neuroinflammation and decreasing neurotrophy. While exercise reduces depressive symptoms in other models of depression, limited research has investigated the efficacy of exercise-related interventions in hyperglycemia-associated depression. Thus, we examined whether chronic exercise could rescue hyperglycemia-related affective dysfunction and modulate neuroinflammatory and neurotrophic levels in male C57BL/6J mice. Hyperglycemia was induced via administration of 50 mg/kg/day streptozotocin (STZ) over 5 consecutive days. Four weeks post-STZ, mice in the exercise group had voluntary running wheel access in their home cage for 6 weeks. As anticipated, STZ induced depressive-like behavior. Exercise attenuated behavioral deficits in the forced swim and splash test. Tissue analyses found that exercise affected hippocampal neurotrophic markers, while STZ influenced cerebellar inflammatory markers. This study provides novel evidence that hyperglycemia and exercise exert brain-region-specific modulatory effects on behavioral alterations
High-fidelity simulation and data-driven modeling of drop aerobreakup.
No full textAerobreakup of liquid drops is essential to various spray applications like fuel injection, drug delivery, spray painting, among others. Due to the highly transient nature and the wide range of spatial scales involved, experimental diagnostics is challenging and high-fidelity numerical simulation is an important alternative to improve the understanding of drop aerobreakup and improve atomizer design. Drop aerobreakup is controlled by multiple dimensionless parameters, including the Weber (We), Reynolds (Re), Ohnesorge (Oh) numbers and liquid-to-gas density ratio, among which, We is most commonly used to characterize different breakup regimes. The goal of this thesis is to characterize the aerobreakup of an isolated drop in a uniform gas stream through high fidelity interface-resolved simulation, and to develop physics-based and data-driven point-particle models for Lagrangian spray simulation. The sharp gas-liquid interface is resolved using a mass-momentum consistent VOF method. The open-source Basilisk solver has been used for the present simulations. The computaitonal domain is discretized using a quadtree/octree mesh to allow local refinement of mesh in user defined region. We have started from simulations of water drops at millimeter size and moderate We. The simulation results for drop shape evolution are validated against experiment and an excellent agreement has been achieved. When the drop is suddenly exposed to a uniform gas stream, the drop first deforms to a disk and then to an inflating bag with a peripheral rim. As the bag undergoes inflation, the liquid sheet thickness decreases over time rapidly. Rupture of the bag is initiated through hole nucleation which gradually expands and gets collected into a rim which surrounds the hole. This rim undergoes destabilization thus forming child drops. The high level details of the flow inside the drop has provided crucial insight to improve models to predict the drop shape evolution. The validated simulation approach is then extended to study the sub-millimeter drops. While drop size decreases, the value of Re and Oh decreases if We is kept constant. The purpose is then to investigate the additional effect of Re on drop deformation and critical We. Since the Rayleigh-Taylor instability (RTI) plays a critical role in the drop deformation and bag formation, when the aerodynamic drag coefficient changes with Re, the resulting acceleration and stability of the interface will change as well. Therefore it is important to thoroughly characterize the relation between the drag and the deformation of the drop over time