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Enhancing Therapeutic Use of Self: The Value of Unfolding Case Studies in Occupational Therapy Education
No full textObjective: This capstone project evaluated the effectiveness of using unfolding case studies (UCS) as a supplemental instructional method to enhance occupational therapy (OT) students’ self-efficacy (SE) in applying therapeutic use of self (TUOS), a core competency in OT education.Methods: Four workshop modules were delivered to and completed by OT students (n=3) enrolled in the occupational therapy doctorate program at the University of Nevada, Las Vegas. The sessions included instructional content, guided discussions, unfolding case study activities, and a TUOS competency. The Self-Efficacy for Therapeutic Use of Self (SETUS) Questionnaire was administered at four points throughout to monitor perceived self-efficacy over time. Findings: Descriptive statistics indicated progressive increases in SETUS scores across all subscales—Self-Efficacy for Therapeutic Mode Use (SETMU), Recognizing Interpersonal Characteristics (SERIC), and Managing Interpersonal Events (SEMIE)—from baseline to post-competency. Qualitative feedback supported these findings, highlighting the workshop’s relevance and the unfolding case study format’s value in promoting confidence and real-time clinical reasoning. Conclusion: Students\u27 perceptions of their self-efficacy in TUOS were positively affected by the UCS-based workshop, suggesting more meaningful and effective ways of bridging theoretical knowledge and practical application in OT education through unfolding case studies. Implementing similar approaches in the future may contribute to the development of other interpersonal and clinical competencies essential to OT practice
Core Temperature While Swimming in Warm Open Water with and Without a Wetsuit
No full textTriathlon is a popular sport which attract participants from all over the world. In general, triathlon is a safe sport with risk of death being about 1.74 deaths per 100,000 participants (Harris et al., 2017). The swimming portion of the race can be dangerous, posing particular risks due to open water conditions and the physical demands of the event. This study investigated the effects of wetsuit use on core temperature in warm open-water swimming (27.9–28.3°C). Four experienced triathletes (2 males, 2 females; age 49.50 ± 7.83 years) completed two 700-meter open-water swims at a submaximal pace—once wearing their personal full-sleeve wetsuit with a maximum thickness not exceeding 5 mm, and once without a wetsuit. Core temperature was continuously monitored using ingestible temperature pills recording at 15-second intervals. Results revealed significant differences in core temperature responses between conditions. Maximum core temperature was higher in the non-wetsuit (NWS) condition (37.76 ± 0.32°C) compared to the wetsuit (WS) condition (37.29 ± 0.26°C; p = 0.024). Similarly, average core temperature was greater in the NWS condition (37.55 ± 0.29°C) versus WS (37.04 ± 0.30°C; p = 0.019). However, the rate of temperature change was significantly higher in the WS condition (0.00060 ± 0.00036°C/s) than in NWS (0.00027 ± 0.00030°C/s; p = 0.02), indicating more rapid heat accumulation with wetsuit use. These findings suggest that while overall core temperature may be higher in non-wetsuit swimming, wetsuit use accelerates temperature rise, which could pose a greater risk of heat stress in prolonged efforts. Individual variations and non-linear temperature changes highlight the need for more detailed analyses of thermoregulatory responses
Dry and Wet Deposition of Atmospheric Microplastics in Las Vegas, Nevada
No full textPlastics have been one of the most widely used man-made materials since their inception, and production is expected to grow by five percent every year. Plastic waste has become a growing global environmental issue. Primary MPs are plastics that are created to be intentionally tiny for their specific functional purpose. Secondary microplastics (MPs) are byproducts of plastic waste occurring due to the breakdown of larger plastics resulting in the presence and accumulation of MPs in the environment. MPs are defined as tiny particles of plastic between 5 mm and 1 μm in size. MPs have been found in the deep ocean, freshwater systems, soil, the atmosphere, and even the human body. Some of Earth’s most remote regions with virtually no humans have been contaminated with MPs suggesting that the atmosphere is a major channel in MPs transport and deposition. The impact atmospheric deposition of MPs has on environmental MPs pollution is unclear due to a lack of research. Being able to identify the potential sources of MPs in the environment is a necessary step in MPs pollution control.This study presents the first evidence of dry and wet deposition of atmospheric MPs in the City of Las Vegas, Nevada. Atmospheric dry and wet deposition samples were collected for a year and MPs deposition fluxes in wet versus dry weather were quantified and compared. The MPs dry deposition fluxes ranged from 3.84×103 to 8.12×104 MPs/m2/day and wet deposition fluxes ranged from 1.53×104 to 1.43×106 MPs/m2/day. The majority of deposited MPs from both wet and dry weather were \u3c 25 μm particles. On average, MPs deposition fluxes in dry weather during spring and winter months were higher than those in fall and summer months. Precipitation events promoted the deposition of atmospheric MPs. Overall, MPs deposition flux per day in wet weather was greater than that in dry weather. MPs dry and wet deposition fluxes were compared to particulate matter (PM) concentrations. MPs wet deposition flux showed a moderate (with outlier) to fairly strong (without outlier) correlation (R2 = 0.560 – 0.778) with average PM10 concentrations prior to rainfall, and a moderate correlation (R2 = 0.577) without the outlier with average PM2.5 concentrations prior to rainfall. The relationships between MPs wet deposition flux and PM2.5 concentrations prior to rainfall with the outlier and the removal effect of precipitation on PM10 and PM2.5 were not statistically significant. MPs dry deposition fluxes and PM10 and PM2.5 concentrations had weak to no correlation and were not statistically significant. These results highlight the importance of atmospheric MPs deposition as a source of environmental MPs pollution
RNA’s Symphony: Harmonizing Splice Junctions and Exon Counts for a Novel Approach to Differential Splicing Analysis
No full textAlternative Splicing (AS) plays a critical role in transcriptome complexity and cell-type-specific gene regulation, yet its analysis remains methodologically fragmented, especially in the context of noisy and sparse single-cell RNA sequencing (scRNA-seq) data. This dissertation addresses key computational challenges in AS detection by evaluating existing tools, developing integrative frameworks, and proposing new strategies for improving analysis accuracy in both bulk and single-cell contexts. In chapter 1, I present a comprehensive literature review of computational tools designed for detecting and quantifying AS from bulk and scRNA-seq data. This review outlines major methodological paradigms, including exon-based and splice junction-based approaches, and evaluates their underlying statistical models, highlighting limitations in resolution, interpretability, and scalability. Chapter 2 introduces GrASE, a novel splicing graph-based method that unifies exon fragment-based and splice junction-based approaches. This unified framework not only facilitates cross-method benchmarking but also reveals AS events consistent across methods, and method-specific biases using short-read RNA-seq data. Lastly, chapter 3 presents a comprehensive benchmarking framework for differential AS detection in scRNA-seq data. Three count structures: exon counts, splice junction counts, and a newly proposed adjacent exon count, are evaluated in combination with three statistical models: negative binomial, beta-binomial, and mixed binomial. This chapter assesses performance across methods and highlights the trade-offs between statistical power and false discovery. A pseudo-bulking strategy is also explored to mitigate noise and enhance detection sensitivity in single-cell datasets. Collectively, this work advances the methodological landscape for AS analysis by providing a unified modeling framework, benchmarking strategies, and practical guidance for robust detection of splicing variation at single-cell resolution
An Examination of The Purity Culture Beliefs Scale and The Interaction of Religiosity, Purity Culture Beliefs, And Pornography Use in A Census-Matched United States Sample
No full textThe impacts of purity culture have been documented in the prevalence of abstinence-only sex education, perception of personal value tied to virginity, and shame and guilt related to sexual behavior. Similarly, models of moral incongruence often examine religiosity as a contributor of distress related to sexual behavior and pornography use, likely tapping into the influence of purity culture without directly naming its presence. This distinction is crucial due to the variety of religious beliefs and practices, some including purity culture and those without sexually restrictive beliefs and practices. Despite this, standardized measures for researching purity culture are limited. Ortiz (2018) created the Purity Culture Beliefs Scale (PCBS) to assess purity culture beliefs and further this area of research; however, this scale has received limited psychometric examination and mainstream utilization thus far. In my dissertation project, I performed both exploratory and confirmatory factor analyses with the PCBS. This allowed me to assess the factor structure of the PCBS in a United States census-matched sample, providing replication and validation of the measure in diverse samples. Additionally, I assessed group differences (i.e., gender, sexual orientation, race) in PCBS scores and conducted path analyses to examine associations among religiosity, purity culture, and pornography use. By examining both problematic pornography use (PPU) and perceived PPU in path analyses with purity culture beliefs as a potential mediating or moderating component, I assessed the factors contributing to moral incongruence (i.e., discriminating the distinct influences of religiosity and purity culture). Factor analyses showed improvement in item loading and cumulative variance in a 9-item, 2 factor version of the PCBS. Path analysis results indicated that purity culture beliefs consistently had a stronger relationship to the pornography outcomes compared to religiosity, supporting this more precise method of assessing moral incongruence through purity culture rather than religiosity. Research findings will help inform researchers and clinicians of the impact of purity culture beliefs on PPU as well as the suitability of the PCBS for assessing purity culture beliefs in a representative sample of United States adults
Assessing the Impact of CDBG And Home Block Grants on Housing Affordability in the Las Vegas–Henderson–Paradise Metropolitan Statistical Area
No full textThis dissertation aimed to analyze the impacts of aggregated federal funding from the CDBG and HOME block grants on temporal changes in the Housing Affordability Index (HAI Change). The temporal change in Housing Affordability between 2011–2015 and 2016–2020 was constructed as the dependent variable to measure the direct and indirect impacts of CDBG/HOME funding. Therefore, this dissertation seeks to identify the impacts of aggregated funding on changes in housing affordability and to explore spatial spillover effects through spatial dependencies that may influence housing affordability change as a dependent variable. The geographical area of this study is the Las Vegas–Henderson–Paradise MSA, Nevada. Research data were collected as secondary data from two primary sources: the ACS five-year estimates (2011–2015 and 2016–2020), and the HUD’s CDBG and HOME dataset portals. The unit of analysis for the models is the census tract, with all finer-level data aggregated accordingly. Finally, four testable models are specified to respond to the research questions.The first model, the OLS model, is designed to address the first research question: Do the CDBG/HOME block grants impact the temporal change of housing affordability? The estimated result for the main hypothesis indicates that CDBG/HOME funding per capita is significantly and negatively associated with housing affordability change and successfully rejects the null hypothesis (1-1). The second model, the SAR model, addresses the research question regarding the spillover effects of housing affordability change (HAI Change) in neighboring areas on the housing affordability change in a given location. The estimation results for this model indicate an insignificant direct impact of CDBG/HOME funding per capita on HAI Change and fails to reject the null hypothesis (2-1). However, the results confirm significant and positive spatial spillover effects of HAI Change on affordability change in a given location or census tract and successfully rejects the null hypothesis (2-2). The third model, the SARMA model, assessed spatial dependencies beyond those captured by the regular SAR Model by estimating the direct impact of CDBG/HOME funding per capita on HAI Change, along with potential spatial dependencies in the dependent variable (HAI Change) and residuals (error term). The results confirmed an insignificant association between CDBG/HOME funding and housing affordability change (HAI Change) (failing to reject Null Hypothesis 3-1), while also indicating the presence of significant spatial dependencies for HAI Change and unobserved elements (error terms) (rejecting Null Hypotheses 3-2 and 3-3). This means that CDBG/HOME funding per capita does not impact HAI Change as the outcome variable, but HAI Change and unobserved elements in neighboring areas significantly produce spillover effects on affordability change in a subject area or neighborhood. The last model, the Spatial Durbin Model, measured the direct impact of CDBG/HOME funding per capita, the spillover effects of funding, and the spillover effects of HAI Change in neighboring areas on HAI Change. The SDM demonstrated a better fit to the data compared to the other models examined in this study. The results of the main hypothesis test in this model revealed that the model failed to reject the null hypotheses for the direct and spillover effects of CDBG/HOME funding per capita on HAI Change (Null Hypotheses 4-1 and 4-2). On the other hand, the results confirmed the spatial spillover effects of affordability change in neighboring areas on HAI Change in a given neighborhood and led to reject the Null Hypothesis 4-3. As conclusion, the OLS model indicated a significant and negative impact of CDBG/HOME funding per capita on HAI Change. However, after controlling for spatial elements—specifically, the spatial lag of dependent and independent variables and the error term—the results of the estimated spatial econometric models confirmed that CDBG/HOME funding is no longer significant. In other words, the impact of CDBG/HOME funding on HAI Change disappeared after controlling for spatial elements. Housing affordability changed because of spatial clusters, not due to funding allocation. Lastly, a set of actionable recommendations is developed for the CDBG/HOME programs administration
Mechanisms Of Gold Enrichment in Seafloor Massive Sulfide Deposits: A Study on the HIGASHI-AOGASHIMA Hydrothermal Field
No full textThe study of Seafloor Massive Sulfides (SMS) deposit formation is vital for assessing both the economic potential and environmental risks posed by future marine mining projects. Metal-rich SMS deposits form in hydrothermal vent systems within tectonically active regions, such as back-arc basins, where faults enhance crustal permeability, enabling fluid migration driven by magmatic heat sources at depth in the crust. Currently our understanding of SMS formation processes is based on bulk-rock geochemical and isotopic data, lacking the necessary spatial and temporal resolution to understand ore forming processes. As a result, critical gaps remain in understanding the exact mechanisms responsible for metal enrichment in these systems, particularly the role of magmatic volatile influx as a source of sulfur and metals such as Au in some hydrothermal systems. Recent research conducted by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) revealed unusually high gold concentrations, reaching up to 275 ppm, in samples from the Higashi-Aogashima Knoll Caldera (HAKC), located on the Izu-Bonin arc, Japan. Three active vent sites have been identified within the caldera, namely the Central Cone, East, and Southeast sites, located at a water depth of ~730 meters below sea level, venting fluid ranging in temperature from 155 to 284°C. This study will investigate the underlying processes driving Au enrichment at HAKC, and SMS deposits more widely. Specifically, this study utilizes in situ sulfur isotope (δ34S) and trace metal geochemistry, to test the hypothesis that magmatic volatile influx is the dominant processes driving Au enrichment at HAKC. The mineralogy of samples varied systematically between the three vent sites and is unusual in a global context due to the occurrence of orpiment (As₂S₃) and realgar (As₂S2), which are exceptionally rare on the seafloor. Chimneys from the East site contain high amounts of barite, colloform and framboidal pyrite and dendritic mineral phases, indicative of high seawater influx. At the Southeast site, chalcopyrite is commonly observed by overprinting galena and sphalerite, indicative of active zone refining processes, which are well developed in samples from the Central Cone site. This transition in mineral assemblage and textures represents a progression in the maturity of chimneys across the three vent sites. Sulfur isotope (δ34S) analysis of sulfide minerals from HAKC, regardless of site and mineral analyzed average 2.7±2.7‰ (1σ, n=178), showing that sulfur is sourced predominately from the leaching of igneous host rocks and thermochemical sulfate reduction (TSR) of seawater. The large range in δ34S values -4.4 to 10.1‰ is attributed to microbial sulfate reduction and variable amounts of TSR, although minor magmatic volatile influx cannot be ruled out. Thus, the absence of δ34S values \u3c 0‰ does not support the hypothesis that magmatic volatile influx is responsible for Au enrichment at HAKC. The deportment of Au between vent sites and different mineral phases shows that Au occurs as both native grains associated with galena and chalcopyrite, and in the matrix of sulfide minerals. Chalcopyrite from the Southeast site and pyrite from the Central Cone host the highest concentrations of Au, whereas the East site contains comparatively lower concentrations, highlighting the potential for large amounts of Au to be contained within sulfide mineral grains. The results demonstrate that Au enrichment at HAKC is not primarily driven by magmatic volatile influx, as initially hypothesized. Instead, spatial variations in Au concentrations, sulfur isotopic signatures and mineral textures across the vent sites suggest that localized fluid processes, such as transient boiling and seawater mixing, play a more dominant role. This study exemplifies the complexity of Au enrichment in arc-hosted hydrothermal systems and the need to integrate various in-situ geochemical approaches to constrain the temporal and spatial evolution of metal transport and precipitation
The Inclusion of Multiracial Participants in Alzheimer’s Disease Research
No full textAlzheimer’s disease (AD) is a growing public health issue which disproportionately affects ethnoracially minoritized individuals and efforts have been made to increase the diversity of research samples. Neuropsychology plays an important role in Alzheimer’s disease and related dementias (ADRD) research as it is used to characterize symptom profiles and disease trajectories. In neuropsychological research, racial identity often acts as a proxy, representing common lived experiences such as school segregation, Native American boarding schools, and other differential treatment on the basis of race which may ultimately influence cognition or its measurement. Despite calls for more ethnoracially representative research that accounts for diverse lived experiences, data from multiracial participants (those identifying with two or more racial groups) seem absent from the literature, with current research focusing on monoracially identified participants. Methods for analyzing and reporting data in ADRD studies have not been established but are needed, as the use of multiracial data regularly requires its misrepresentation or exclusion. Given the confluence of disease, cognition, and race, further research is needed to ensure the ethical inclusion of neuropsychological data from multiracial participants. This dissertation sought to explore the inclusion of multiracial participants and their neuropsychological data in ADRD research through three unique research projects. Study One characterized the use of neuropsychological data from multiracial participants in ADRD research literature and made recommendations for improved inclusion. Study Two examined the impact of typical clinical trial inclusion and exclusion criteria on participant eligibility and retention, with a special focus on multiracial individuals. Through interviews with multiracial adults, Study Three explored common themes in reactions to current common classifications in the analysis of data from multiracial participants to better inform analytical practices. Findings from this dissertation have implications for the inclusion of multiracial participants and their neuropsychological data from study designthrough recruitment, participation, analysis and reporting
Development of an Access Charge Framework for High-Speed Rail Incorporating Rail Replacement Costs and Dynamic Train Characteristics
No full textThis thesis develops a framework to determine track access charges for shared high-speed rail corridors, with a focus on rail replacement cost driven by train-induced loads. The method explicitly accounts for both static loads, resulting from axle weights, and dynamic loads that arise from train speed and track geometry, particularly curvature. Train characteristics such as axle load, operating speed, frequency of service, and number of wheels are integrated with track parameters, including curve radius, to calculate the total vertical load. These loads are used to estimate the cumulative tonnage threshold for rail replacement and the resulting service life of the track segment.The framework proceeds to calculate the total rail replacement cost, projects it to the end of the rail\u27s service life using inflation-adjusted rates and converts this cost into an equivalent annual amount. The annualized cost is then proportionally allocated to each train operator based on their calculated contribution to the cumulative rail loading. Finally, the per-trip access charge is calculated. A case study on the Palmdale–Burbank corridor planned to be shared by California High-Speed Rail (CAHSR) and Brightline West, demonstrates the framework’s application. Using publicly available and assumed operating data, the analysis shows that CAHSR trains contribute a greater share of total rail wear due to their higher axle loads, operating speed, and service frequency. Consequently, CAHSR is assigned a higher per-trip access charge than Brightline West. These results confirm that the proposed method provides an effective approach for allocating rail replacement costs based on actual infrastructure use
Socio-Cultural Correlates of Breastfeeding Behavior Among Latina Mothers and Its Implications for Child Health
No full textBackground: Latina mothers in the United States report lower rates of breastfeeding initiation and exclusivity than their non-Hispanic counterparts. Lower rates of breastfeeding in infancy may lead to a higher rate of excess weight in childhood and adverse health conditions. Breastfeeding disparities in Latina women have been previously correlated with socio-cultural factors such as acculturation, education, income, nativity, and marital status. This study examines whether socio-cultural factors are associated with breastfeeding behaviors in Latina mothers in Nevada. Methods: Participants were Latina mothers [n = 214] over 18 years of age, with a child 2–5 years old. A logistic regression was conducted to assess the associations between acculturation, age, marital status, education, and nativity with breastfeeding. Results: Mothers who were married/living with their partner had 2.3 greater odds (95% CI = 1.08, 4.73; p-value \u3c 0.05) of breastfeeding than the mothers who were not in a relationship, and mothers who were born outside the US had 4 times greater odds of breastfeeding than mothers who were born in the US (95% CI = 1.178, 13.514; p-value \u3c 0.05). No significant association was found for acculturation (OR = 1.13; 95% CI = 0.74, 1.7; p-value = \u3e 0.05), maternal age (OR = 1.01; 95%; CI = 0.96, 1.07; p-value = \u3e 0.05) and education (OR = 0.81; 95% CI = 0.37, 1.8; p-value = \u3e 0.5). Conclusions: These findings suggest that a romantic partner may be supportive of breastfeeding, and foreign-born mothers may retain their cultural norm of breastfeeding. These results can be applied to develop a culturally tailored intervention to promote breastfeeding behavior