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Analyses of Thermal and Spectral Characteristics of Artificial Turf and Natural Grass in Las Vegas Valley
No full textThis thesis presents a comprehensive analysis of the thermal and spectral characteristics of Las Vegas Valley (LVV). The first objective examines the effects of artificial turf on the urban thermal environment in the LVV by analyzing the impact of Land Surface Temperature (LST) and surface albedo at 26 ROIs that transitioned from natural to artificial turf, alongside another 26 ROIs that remained unchanged between 2018 and 2022 utilizing available Landsat 8 satellite images for the respective years. In the comprehensive comparison of ROIs over the two years in question, it was observed that transitioning to artificial turf correlated with elevated surface temperatures, but only during the warmer months. Two series of paired T-Tests results, taking the combined annual and seasonal data, revealed significant differences on the LST of the transitioned ROIs indicating turf transition had substantial impact on LST for these ROIs. The albedo values for sites with natural grass remained relatively unchanged between the two years. Conversely, a notable decrease in albedo was observed in most sites that transitioned to artificial turf. The T-Tests revealed significant differences in albedo between 2018 and 2022 for these transitioned sites.
The second objective examined the spectral signatures of 26 transitioned ROIs in both 2018 and 2022 by creating spectral signature curves and analyzed Normalized Difference Vegetation Index (NDVI) at both transitioned and non-transitioned ROIs in both years by creating the NDVI maps. For the spectral signatures, the 2018 curves had features indicative of natural grass, while the 2022 curves did not show these traits. The most evident distinction was in the SWIR1 region\u27s reflectance, with opposing slope directions in the two years. Interestingly, despite being plastic, the synthetic turf exhibited increased reflectance in the SWIR1 region, possibly due to surface temperature effects. Average reflectance values of all 26 ROIs of each month of 2018 and 2022 at each wavelength displayed distinct curves for each year. Two sets of paired T-Test results, one for each month and the other for each ROI, presented significant differences in the reflectance values between 2018 and 2022 due to the turf transition. Distinct NDVI values and curves were obtained for artificial turf. T-Test results confirmed the significant differences on NDVI due to the turf transition as well. The entire analysis for the first and second objectives was conducted using GEE and ArcGIS Pro, with statistical assessments carried out in R-Studio.
This thesis includes an additional chapter that examines the health and environmental effects of artificial turf. It covers issues such as the use of recycled tire crumb as infill, the presence of microplastics in turf components, and the composition of turf fibers. It also addresses health risks like Methicillin-Resistant Staphylococcus Aureus (MRSA) infections, heat-related illnesses, and various injuries that athletes might suffer on artificial playing surfaces. On the environmental side, the focus is on the higher temperatures of turf surfaces, ecological damage from toxic substances, and a greater risk of flooding. The thesis suggests that the decision to install artificial turf should be tailored to the unique conditions and requirements of each location.
Studying the impact of artificial turf on the urban thermal environment of LVV can be helpful for informed urban planning and policymaking, aimed at creating a healthy and comfortable urban environment, especially considering the unique climate challenges of the region
Statistical Classification using Selection and Ranking Methodologies with Statistical Learning
No full textThe subject of Statistical Classification is concerned with identifying and allocating future observations into one of the pre-categorized classes based on the characteristics of the objects. Typically, these decisions to classify and categorize the objects have been dependent on identifying a system of classification, and from there, determining attributes for sorting.
In past decades, from discriminant analysis, various methods have been developed for classification. In particular, the rise of artificial intelligence (AI), machine learning, and statistical learning theory has made it possible to consider improving the existing methods along with new developments and more comprehensive schemes in conjunction with data-driven methods.
In this dissertation, we propose innovation using multiple decision-theoretic perspectives, such as the Indifference-Zone (IZ) approach and the Subset Selection (SS) method, to improve and clarify how these classification decisions can be made
Mindfulness for Middle School Students Receiving Adapted Physical Education Services: Quality Improvement Program
No full textMiddle school students with disabilities are often isolated from their peers with decreased opportunities for participation, struggle with social emotional regulation, and self-efficacy. This has been evident among students with various disabilities who are from various age groups receiving special education services including adapted physical education (APE). Research has shown mindfulness amplifies learning and promotes a positive environment that supports children’s overall wellbeing. This quality improvement project focused on developing an occupational therapy centered mindfulness program to enhance social participation, self-efficacy, and social-emotional regulation. Data collection occurred pre and post program from specialized program teacher assistants (SPTAs) using the School Participation Questionnaire (SPQ v1.4) to understand their perceptions of the mindfulness programs impact on middle school students receiving APE services. The program involved 15 middle school students receiving APE services during two separate general physical education (GPE) classes at one local CCSD middle school. Students that participated were boys with autism spectrum disorder (ASD) and a mixed gender functional life skills (FLS) class with varying disabilities. Outcomes from the program did not show statistically significant results from combined totals on the SPQ v1.4. However, the boys with Autism results showed increased scores pre and post program for Being and Doing factors of the SPQ v1.4
Behavioral Health, Mental Health, and Overall Well-Being of Informal Caregivers Before and After the Covid-19 Pandemic
No full textInformal caregivers, such as relatives or close friends, are vital for maintaining the welfare of the individuals they provide care for. However, caregiving can be difficult and stressful that adversely impacts caregivers’ health. The extra stress brought on by the COVID-19 pandemic can potentially aggravate health problems, particularly mental health. The current research aimed to nationally analyze whether the COVID-19 pandemic was significantly associated with behavioral health (physical activity and smoking), mental health (worrying, nervousness, hopelessness, little interest, and psychological distress score), and the perception of overall well-being among informal caregivers in the United States. Whether behavioral health could mediate mental health and overall well-being was also investigated.
The Health Information and National Trends Survey (HINTS), spanning the pre-pandemic period (2017–2019) and the post-pandemic era (2020, 2022), was the data source. Weighted multivariable survey logistic regression models were employed for all outcomes. Predictors for mental health and overall well-being were behaviors, including smoking and physical activity. All models were additionally adjusted to account for sociodemographic factors.
Post-pandemic, caregivers exhibited significantly higher odds of reporting “worrying” (OR = 1.43, 95% CI: 1.10-1.87, p = 0.0081) and overall unwell-being (OR = 1.33, 95% CI: 1.05-1.69, p = 0.0159). Caregivers who had insufficient physical activity compared to their physically active counterparts had higher odds of perceiving their overall well-being as diminished (OR=1.80, 95% CI: 1.17-2.79, p=0.0077). Smoking and insufficient physical activity had significant association with all mental health issues studied here, except for insufficient physical activity for “nervous”.
This research revealed that informal caregivers experienced a decline in the mental health and overall well-being in the United States following the COVID-19 pandemic. Behavioral health, including smoking and insufficient physical activity, were significantly associated with mental health and overall well-being. This research provides updated insights for policymakers on the importance of addressing the mental health and overall well-being of informal caregivers during a crisis. Tailored interventions are required to address these health issues among informal caregivers. Targeted policies are also recommended, prioritizing the behavioral health of informal caregivers to enhance their mental health and overall well-being
Tilt Instability of Retrograde Disk Around One Component of a Binary
No full textBe/X-ray binaries are systems containing a massive Be main sequence star and a compact object companion. The Be star contains a disc of material that flows from the Be star, and may interact with the companion. In this work we consider a neutron star companion. With hydrodynamic simulations, we show that a coplanar disc around one component of a binary can be unstable to global tilting when the disc orbits in a retrograde direction relative to the binary. The disc experiences the largest inclination growth relative to the binary orbit in the outermost radii of the disc, closest to the companion. This tilt instability also occurs for test particles. A retrograde disc is much larger than a prograde disc since it is not tidally truncated and instead spreads outwards to the orbit of the companion. The coplanar retrograde disc remains circular while a coplanar prograde disc can become eccentric. We suggest that the inclination instability is due to a disc resonance caused by the interaction of the tilt with the tidal field of the binary. This model is applicable to Be/X-ray binaries in which the Be star disc may be retrograde relative to the binary orbit if there was a sufficiently strong kick from the supernova that formed the neutron star companion. The accretion on to the neutron star and the resulting X-ray outbursts are weaker in the retrograde case compared to the prograde case
Examining the Risks and Resilience of Older Adults Living with HIV/AIDS: Qualitative Community-Based Participatory Research Studies in Southern Nevada
No full textSince the height of the HIV pandemic in the 1980s, medical interventions have significantly increased the life expectancy of people living with HIV/AIDS (PLWH) and made HIV/AIDS a livable, chronic health condition. Because of this, PLWH have been living longer lives and thriving with the help of HIV sector healthcare and service providers. However, with their longer life expectancy, older PLWH have been experiencing other health challenges. One such challenge is the risk of developing HIV-Associated Neurocognitive Disorder (HAND), which is a condition that affects up to 50% of PLWH at some point in their lifetime, with middle-aged and older PLWH being most at risk. In this three-paper dissertation, the awareness and knowledge of the specific risk of PLWH developing or experiencing neurocognitive challenges as they age as a result of HAND among relevant study participants (i.e., middle-age and older PLWH and their HIV sector providers) from Southern Nevada are examined and discussed in the first two papers. Looking beyond the risks aging PLWH face, the third paper of this three-paper dissertation takes on a more strengths-focused approach to examining the circumstances and experiences of study participants. It directs its attention to the inherent resilience of PLWH, specifically the resilience of middle-aged and older men who have sex with men (MSM) living with HIV/AIDS, the subpopulation of PLWH that has inarguably been impacted the most and the longest by HIV/AIDS since the global pandemic started in the 1980s
Lake Mead: A Living Museum
No full textLake Mead, the largest man-made water project in the nation and a prolific source of electricity, irrigation, and recreation for much of the western population, is currently experiencing a drastic transformation. Amid the ongoing water crisis parching the west, the once overflowing reservoir is consistently shrinking, descending into depths historically uncharted.
While serving as a bleak demonstration of climate change’s effects, the body of water is simultaneously assuming an alternative role that may be less apparent to the public. As water levels decline, Lake Mead is actively metamorphosing into a “Living Museum”, by gradually unveiling previously submerged artifacts. As a result, it is displaying pieces of the local and regional history that were formerly concealed by its watery domain. Lake Mead’s evolving identity has inspired further investigation into what the lake has been storing since its inception nearly a century ago. This creative thesis project adopts the format of an audio documentary, delving into the supplementary persona of Lake Mead and its surrounding areas. By weaving together an interdisciplinary collection of expertise surrounding Lake Mead, this endeavor will work to explore the concealed histories, cultural nuances, and the mysterious artifacts sprouting from the waters. By providing Lake Mead with an alternative narrative, this thesis aims to present a creative and compelling interpretation through which to observe the diminishing reservoir. In doing so, it provides a divergence from the predominant storyline shaped by the climate crisis
Quaternary Ammonium Compound Resistance of Klebsiella Pneumoniae and Klebsiella Quasipneumoniae Strains Isolated from the International Space Station
No full textThe International Space Station (ISS) has been continuously inhabited for twenty-three years and harbors a diverse population of microorganisms under conditions of microgravity, elevated radiation, and relative isolation, including Biosafety Level 2 (BSL-2) opportunistic pathogens. To sanitize surfaces on the ISS, astronauts use a combination of four antimicrobial quaternary ammonium compounds (QACs). As the stresses of space flight are known to stimulate virulence and antimicrobial resistance in bacteria, the frequent use of QAC disinfectants on the ISS is of concern to NASA. This not only poses risks to astronauts during future long-term space travel, but there is also a concern that these hypervirulent and multidrug-resistant strains will be returned to Earth by astronauts.
For my master’s thesis, I studied strains of Klebsiella pneumoniae and Klebsiella quasipneumoniae, opportunistic BSL-2 pathogens that were isolated from the interior surface microbiome of the ISS, with particular emphasis on how these ISS-adapted strains differ from an Earth-origin type strain when exposed to QACs. This thesis consists of four chapters: Chapter 1, an introduction and literature review; Chapter 2, a description of the complete genome of a strain of Klebsiella quasipneumoniae isolated from the ISS, which was published in 2022 in Microbial Resource Announcements; Chapter 3, a study of the responses of both ISS- and Earth-origin strains of Klebsiella to QAC exposure; and Chapter 4, a conclusion.
The first research chapter (Chapter 2) consists primarily of in silico work to complete the genome of Klebsiella quasipneumoniae subsp. similipneumoniae strain IF3SW-P1, isolated from the ISS; this included assembly and annotation of the genome based on long-read Oxford Nanopore Technology sequencing data. The completed genome was then analyzed for the presence of putative virulence and antimicrobial resistance genes. The second research chapter (Chapter 3) consists of experimental approaches to study the responses to QAC disinfectants by both ISS- and Earth-origin strains of Klebsiella. This work included determining the minimum inhibitory concentration (MIC) of QACs for each strain before conducting viability assays at both sub-lethal and standard QAC concentrations. These viability assays included viability qPCR using the viability dye PMAxx, and fluorescence microscopy conducted using LIVE/DEAD BacLight viability dyes. This work showed significant differences in the response of the two ISS-origin strains of Klebsiella, as well as differences between the ISS-origin strains and the Earth-origin type strain, in both the amount of QACs required to inhibit growth of the strains and in the responses of the strains after exposure to lethal QAC concentrations. This suggests the ISS-origin strains, which are frequently exposed to QACs in the ISS environment, may be less susceptible to QACs
Effectiveness of an Occupational Therapy-Focused Stroke Transitional Care Program in an Inpatient Rehabilitation Facility
No full textIntroduction: As a global health issue, stroke is one of the most common causes of disability for individuals around the world. The American Heart Association (2024) mentions that stroke is the fifth-highest cause of mortality and the top cause of disability in the United States. Objective: This project aimed to assess the change in the perceived readiness of individuals after implementing an occupational therapy (OT)-focused transitional care program for patients with stroke and their caregivers before returning home. Methods: The recruitment process for participants involved purposive sampling methods. The study utilized both the Readiness for Hospital Discharge Scale-Short Form (RHDS-SF) or Preparedness Assessment for the Transition Home After Stroke Instrument®s2018 (PATH-s) to assess the perceived readiness of individuals with stroke and their caregivers at an inpatient rehabilitation facility (IRF) before and after completing the Stroke Transitional Care Program (STCP). Results: An OT-focused STCP increased perceived readiness to return home before hospital discharge for patients with stroke; contrary, it did not significantly affect caregivers. Conclusion: The stroke population and the OT profession will benefit from further research to contribute to the limited body of knowledge and the continual application of STCP in practice
Examining the Impacts of UNLV\u27s Tobacco-Free Policy Pre and Post Implementation
No full textDespite the known harmful effects of smoking and secondhand smoke, tobacco-related disease, disability, and death continue to plague the United Stated and contribute to more than 480,000 individuals dying prematurely every year. Comprehensive smoke-free and tobacco free policies strive to prohibit the use of both traditional forms of tobacco (cigarettes, cigars) and smokeless forms of tobacco (vapes). The goal of this project was to examine the impact a tobacco control policy has on prevalence rates of use and knowledge regarding said policy among faculty, staff, and students. In the Fall of 2022, UNLV adopted a comprehensive tobaccofree and smoke-free policy (TFCP). Cross-sectional surveys were distributed to the UNLV community (students, faculty, and staff) in Spring 2022 (pre-implementation) and Fall 2022 (post-implementation) to gauge support for TFCP and examine rates of tobacco and nicotine product use on campus. Prevalence rates were higher for tobacco products at postimplementation among students, faculty, and staff at 28%, and 25% to 37% compared to pre- implementation rates of 10%, 7%, and 12%, respectively. Additionally, higher prevalence rates were observed in nicotine product use with students at post-implementation from 17% to 37%, faculty from 6% to 20% and staff from 7% to 36%. Support for policy was higher preimplementation among students (m = 3.8, SD = 1.1; m = 3.4, SD = 1.3), faculty (m = 3.8, SD = 1.2; m = 3.4, SD = 1.3), and staff (m = 3.5, SD = 1.3; m =3.3, SD 1.3). Policy perceptions and tobacco/nicotine product use varied by sociodemographic characteristics of students, faculty, and staff. Despite observing higher prevalence rates post-implementation this study has contributed to understanding gaps in the literature such as how these policies affect different subgroups of college subpopulations (e.g., 1st generation students and sexual and gender minorities). Identifying predictors for support of college campus TFCP can help to inform future research on impacts of policy implementation