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Examining Dietary Intake, Food Security and Health Among the Population with Low Incomes
No full textFood insecurity describes the lack of access to foods and affects 10.2% of general U.S. households and 27% of low-income households in 2021. Food insecurity is a pervasive public health concern in the United States and has been linked to poor dietary intake and diet quality, overweight and obesity (especially among women), and risk of other chronic diseases, such as diabetes, hypertension and dyslipidemia. To better understand food security status and address its associated health and dietary outcomes among low-income populations, a conceptualized model was built and served as research framework for the dissertation, including 1) internal factors and motivations, such as traits related to self-efficacy and sufficiency that may influence diet and health; 2) external factors of temporary support, such as financial benefits from assistance programs that low-income populations are eligible for that may influence diet and health; and 3) external factors of potentially long-term support, such as nutrition education programs targeting low-income groups that may foster internalized knowledge that could sustain impact and improvement of diet and health in the long-term. Each chapter of this dissertation addresses a component of the model. Cross-sectional analysis of a sample of rural veterans using food pantries quantified psychological traits related to self-motivation and efficacy including grit and help seeking, at the individual and internal factors level of the conceptualized model, and their links to food security and resource use, and revealed an inverse association between grit score and risk of food insecurity. The findings provided evidence for future interventions targeting food insecurity improvement to include education and resources that address traits related to self-efficacy, such as grit, among low-income populations to improve health outcomes directly or through improving food security or use of resources. Using nationally representative data, the second study investigated relationships between food assistance through the Supplemental Nutrition Assistance Program (SNAP) participation, a type of societal level external support, and dietary outcomes among low-income older U.S. adults. There were no differences in dietary quality, usual nutrient intake or risk of inadequacy between SNAP participants and eligible nonparticipants. Furthermore, results revealed a high prevalence of not meeting the Estimated Average Requirement from dietary sources for several nutrients (vitamins A, C, D, E, calcium, and magnesium) but the prevalence was lower when nutrients from dietary supplements were included. The results highlight a need for continued effort to improve nutrient and dietary intake among low-income older adults. External factors of potentially long-term support (e.g. nutrition education and food assistance) were evaluated for relationships with body mass index. A longitudinal sample of low-income women interested in participating in nutrition education through SNAP-Education (SNAP-Ed) was examined to determine the relationship between nutrition education (SNAP-Ed) and food assistance program participation through (SNAP, WIC), separately and in combination, with long-term changes in body mass index. No differences in changes of weight status over time were observed by nutrition education, food assistance, or combination participation. The prevalence of obesity was high among this sample, calling for targeted obesity prevention interventions and further support of healthy lifestyle promotion among low-income populations. The findings shown in this dissertation further reveal a high health burden among low-income groups. The studies filled several research gaps described in the conceptualized model. The results may be used to inform future tailored interventions to address food insecurity, dietary and health outcomes at individual and societal levels, incorporating internal motivation and external support to mediate health and dietary risks among low-income population
An Experimental Investigation of Varied IGV Stagger Angle Effects on a High-Pressure Compressor
No full textThe focus of this work was to characterize the overall performance effects due to altering the stagger angle of a variable inlet guide vane (VIGV) on a multistage axial compressor. Data were collected from the Purdue three-stage axial compressor (P3S). The stagger angle from the VIGV was varied thrice from the baseline configuration in increments of 5 degrees resulting in four configurations with angles of 4 deg, 9 deg, 14 deg, and 19, where the baseline configuration was 9 degrees. Compressor performance data were collected and analyzed for each stagger angle configuration along three corrected speeds (68%, 80%, 100%). Each speedline consisted of approximately six loading conditions for which the corrected mass flow rate was matched for each configuration to allow for a basis of comparison among the configurations. Stalling mass flow rates and stall inception were also investigated. Total pressure and total temperature rakes were installed throughout the compressor to investigate the performance at interstage locations for each loading condition. In addition to the rakes, static pressure taps were distributed along the compressor and unsteady pressure measurements were distributed circumferentially. Capacitance probes were installed over each of the three rotors to evaluate rotor tip clearance measurements during the tests. The effects of the stagger angle on the stability margin of the compressor were also characterized. Each speedline presented, thus, includes a representative stall point in addition to the six loading conditions where detailed flow field traverses were conducted. The results of this investigation showed that while the total pressure ratio (TPR) increased as the stagger angle decreased, the stability margin was reduced. The opposite trend was observed with a decrease in overall TPR across the compressor and an increase in stability margin for increased stagger angles. Based on findings from previous authors, this trend was anticipated. A similar metric for monitoring compressor performance is isentropic efficiency. This investigation utilized both temperature-based and torque-based isentropic efficiency. The greatest effect of the VIGV stagger angle on compressor isentropic efficiency occurred at the lowest loading conditions, and there was no discernible impact on isentropic efficiency at high loading conditions for this case. As VIGVs typically have the greatest impact on off-design conditions, this trend was expected. The varied stagger angle configurations had no discernible effect on the type of stall inception mechanism experienced by the compressor. The primary effect on stall that was consistent across the configurations was a noticeable increase in the duration and strength of modal oscillations present throughout the compressor with increased stagger angles, indicating an increase in stability. The data collected and presented herein provide a unique, robust dataset to improve understanding of the effects of changing stagger angles on variable inlet guide vanes on multistage axial compressors. These data correspondingly provide a unique training set and validation method for predictive technology
Reduced Modelling of Oscillatory Flows in Compliant Conduits at the Microscale
No full textIn this thesis, a theory of fluid-structure interaction (FSI) between an oscillatory Newtonian fluid flow and a compliant conduit is developed for canonical geometries consisting of a 2D channel with a deformable top wall and an axisymmetric deformable tube. Focusing on hydrodynamics, a linear relationship between wall displacement and hydrodynamic pressure is employed, due to its suitability for a leading-order-in-slenderness theory. The slenderness assumption also allows the use of lubrication theory, which is used to relate flow rate to the pressure gradient (and the tube/wall deformation) via the classical solutions for oscillatory flow in a channel and in a tube (attributed to Womersley). Then, by two-way coupling the oscillatory flow and the wall deformation via the continuity equation, a one-dimensional nonlinear partial differential equation (PDE) governing the instantaneous pressure distribution along the conduit is obtained, without a priori assumptions on the magnitude of the oscillation frequency (i.e., at arbitrary Womersley number).The PDE is solved numerically to evaluate the pressure distribution as well as the cycle-averaged pressure at several points along the length of the channel and the tube. It is found that the cycle-averaged pressure (for harmonic pressure-controlled conditions) deviates from the expected steady pressure distribution, suggesting the presence of a streaming flow. An analytical perturbative solution for a weakly deformable conduit is also obtained to rationalize how FSI induces such streaming. In the case of a compliant tube, the results obtained from the proposed reduced-order PDE and its perturbative solutions are validated against three-dimensional, two-way-coupled direct numerical simulations. A good agreement is shown between theory and simulations for a range of dimensionless parameters characterizing the oscillatory flow and the FSI, demonstrating the validity of the proposed theory of oscillatory flows in compliant conduits at arbitrary Womersley number
Water Animation Using Coupled SPH and Wave Equations
No full textThis thesis project addresses the need for an interactive, real-time water animation technique that can showcase visually convincing effects such as splashes and breaking waves while being computationally inexpensive. Our method couples SPH and wave equations in a oneway manner to simulate the behavior of water in real-time, leveraging OpenGL’s Compute Shaders for interactive performance and a novel Uniform Grid implementation. Through a review of related literature on real-time simulation methods of fluids, and water animation, this thesis presents a feasible algorithm, animations to showcase interesting water effects, and a comparison of computational costs between SPH, wave equations, and the coupled approach. The program renders a water body with a planar surface and discrete particles. This project aims to provide a solution that can meet the needs of various water animation use-cases, such as games, and movies, by offering a computationally efficient technique that can animate water to behave plausibly and showcase essential effects in real-time
I’ve Seen This, So I’ve Got This! Exploring the Use of Imagery and Self-Talk Within Action Sports Athletes
Get PDFThe present study aimed to expand the current knowledge of psychological skills usage within athletes of action sports by exploring the use of imagery and self-talk within skateboarders and snowboarders. Skateboarders and snowboarders (N 5 74) completed the Athletic Coping Skills Inventory (ACSI-28; Smith et al., 1995), the Self-Talk Questionnaire (S-TQ) for sports (Zervas et al., 2007), and the Sport Imagery Questionnaire (SIQ; Hall et al., 1998). Results indicated that participants scored significantly higher than reported norms of traditional athletes (Smith et al., 1995) on the coping with adversity and goal-setting/mental preparation subscales of the ACSI-28, and to a similar degree to traditional athletes on the remaining subscales. However, participants scored significantly lower on the total score of the ACSI-28 than previously reported action sports athletes (Young & Knight, 2014). Participants scored significantly higher than reported norms of traditional athletes on the cognitive functional and motivational functional subscales of the S-TQ. On the SIQ, participants scored significantly lower than reported norms for traditional athletes (Hall et al., 2005) on the MG-M subscale, while scoring similarly to reported norms on the CG, CS, MS, and MG-A subscales. Results of the present study confirm that action sports athletes utilize psychological skills to a degree similar to that of traditional athletes, and that skateboarders and snowboarders specifically include the use of imagery and self-talk within their psychological skills arsenal
Journal of Pre-College Engineering Education Research (J-PEER) Annual Report from January 1, 2022, to December 31, 2022
Get PDFIn this annual report, we present our reflections on 2022 along with the Journal of Pre-College Engineering Education Research (JPEER) readership trends and authorship metrics. In 2022, J-PEER published two issues in volume 12 comprised of 17 articles. The second issue of the year included a special issue on the impact of COVID-19 on education, marking the impact that the pandemic had on pre-college engineering education
The Paradoxes of Contingency: Stories of Contingent Professional Tutors’ Lived Experiences
Get PDFDespite comprising the majority of labor in higher education in general and writing centers more specifically, contingent workers’ voices and experiences have often been overlooked. The contingent voices that have been represented have predominantly been those in director or administrative positions, not the professional tutors who engage in centers’ day-to-day consulting. This lack of representation in the literature perpetuates institutional inequities and belies a larger paradox: that contingent workers attempting to ameliorate the precarity of their situation may jeopardize their livelihood. Because contingent workers’ identities and roles have historically been ignored and marginalized, few research and publication options are available to them. For this reason, this research used autoethnography, one of the only methodologies available to the contingent professional tutor authors that allowed us agency to share our lived experiences and identities as contingent workers. Three themes emerged from our autoethnographies: vital to but not valued by the institution, working to live but destroying the body, and the illusion of choice. After discussing themes, we call for a continuation of what this work begins, particularly that the field of writing center studies should aim for wider representation of contingent and multi-identitied voices in its literature, conferences, and leadership organizations
The satisfaction of thalassotherapy visitors and its influence of word-of-mouth
No full textThis work aims to contribute to the field of service quality in wellness tourism by analysing the influence of a particular kind of services, namely thalassotherapy services, on customers’ overall satisfaction. Additionally, the influence of overall satisfaction on positive word-of-mouth (WOM) on said services is also examined. To fulfil these research goals, structural equation modelling was performed on a sample of 246 thalassotherapy customers. The results show that customers’ satisfaction with each thalassotherapy activity (i.e. swimming pool treatments, body/face treatments, the environment and the staff) has a positive impact on overall satisfaction. Additionally, overall satisfaction positively affects WOM. These results have practical implications, since they suggest that performing well only in the provision of treatments is not enough if there are service failures in terms of environment or staff
TOURISTS’ PREFERENCES FOR ENERGY AND DIGITAL TRANSITION PROGRAMS IN MARINAS
No full textLittle is known about yacht tourists\u27 environmental concerns and attitudes towards sustainability management in marinas. This study assesses sailors’ preferences and willingness to pay for the energy and digital transition programs that can be implemented in marinas. A discrete choice experiment is designed and empirically validated with European sailors that used to moor in the marinas of the Canary Islands. Results show that sailors have a greater preference for solid waste management, renewable energy use and energy and water-saving programs. Besides, individuals were indifferent to health security programs and environmental certifications. By identifying low carbon solutions that have the greatest potential to increase the perceived well-being of port users, incentive schemes for the industry can be designed in more efficient terms
Committing to be a better traveler: an experimental study of travel pledges
No full textTravel pledges are being implemented at destinations such as Palau, Iceland, and New Zealand. Travel pledges are not contracts, but rather a commitment device that hopes to nudge consumers into adopting a certain desired behavior, in this case, responsible travel. The present study aims to empirically assess how travel pledges affect the self-reported intention to travel responsibly among undergraduate students. The current study will contribute to the lack of literature regarding travel pledges and provide information to destination management organizations or affiliated associations and parties on the value of travel pledges. The online survey will use a hypothetical spring break vacation to gather data on how responsible travel behavior intention is affected by the utilization of travel pledges