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The Effects of Blood Flow Restriction and Body Weight Support Treadmill Walking on Electromyographic Activity in Lower Limb Muscles
No full textBlood flow restriction (BFR) is an emerging rehabilitation modality shown to enhance muscle activation and elicit strength gains comparable to high-intensity training at lower loads (Cognetti et al.,2019). Body weight support (BWS) treadmill walking is another modality that has gained popularity due to the effect it has on lowering muscle activation with increasing support levels (Jensen et al.,2016). However, to date no research has looked at electromyographic (EMG) activity utilizing both modalities concurrently. This study investigated if stride frequency (SF) and muscle activity of the rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA) and gastrocnemius (GA) would be influenced by an interaction between BWS and BFR. Seven healthy participants (3 men and 4 women; age: 23.71 3.01yrs; height: 171.27 6.91 cm; body mass: 64.38 4.94 kg; body fat percentage: 18.76 5.44 %) completed four walking conditions at 0% & 50% BWS with and without 80% occlusion pressure of BFR at a self-selected speed. EMG activity was recorded for 30s during each condition. Results revealed that EMG activity was not influenced by an interaction between BWS and BFR for SF (P=.345), RF (P=.845), BF (P=.684), TA (P=.761) and GA (P=.129). Additionally, BFR alone did not influence EMG activity across muscles (SF (P=.161);RF (P=.639); BF (P=.684);TA (P=.479);GA (P=.404)), nor did BWS ( SF (P=.740); RF(P=.675); BF (P=.900); TA (P=.102), except for GA (P=.039). These finding suggest that BFR did not influence EMG activity regardless of BWS. Thus, suggesting that further research is needed to further explore the neuromuscular effects of BFR under varying levels of BWS and walking speeds
Detection And Quantification of Total Airborne Fungi and \u3cem\u3eCoccidioides\u3c/em\u3e Species in Environmental Samples
No full textFungal exposure can cause acute and chronic illnesses or exacerbate existing illnesses. Some fungi are opportunistic pathogens and can lead to serious systemic fungal infections. In 2020, more than 150 million cases of severe fungal infections were reported globally resulting in an estimated 1.7 million deaths. Coccidioidomycosis, or Valley fever, is classified as a serious fungal infection caused by the fungi Coccidioides immitis and C. posadasii. These particular fungi are prevalent in the soil of the Southwestern United States, including Las Vegas, Nevada. In 2024, there were a total of 269 cases of Valley fever reported in Nevada, and 239 of those cases were reported in Las Vegas. This study aimed to provide a comprehensive assessment of the airborne concentration of both total fungi and Coccidioides species across different seasons, weather patterns (non-weather vs. weather event), and meteorologic factors (temperature, relative humidity, and wind) in Las Vegas, Nevada. Validation and optimization of a universal fungal PCR assay was conducted using 47 fungal species. The universal fungal PCR assay was able to detect all target fungal species. Two different master mixes (Universal Fast Advanced and TaqPath BactoPure) were tested to determine which one was more effective at overcoming PCR inhibitors. There was a statistically significant difference between the master mixes (p = 0.03). Environmental air samples from 13 sites across Las Vegas were collected in 2022 and analyzed with a validated universal fungal PCR assay and a Coccidioides species PCR assay. Selected samples were collected during high winds/dust advisories. The total concentration of airborne fungi was determined from a composite standard curve that was constructed using the universal fungal PCR assay and DNA from Aspergillus flavus and A. fumigatus. The mean total fungal concentration in the non-weather samples was 754 copies/m3 of air, and 741 copies/m3 of air in the weather event samples. There was no statistically significant difference in the mean concentration of fungi between the two sample types (p = 0.74). There was a significant difference in the mean total fungal concentration between seasons (non-weather p \u3c 0.001; weather event p = 0.03). There was also a significant correlation between total fungi and temperature in the non-weather environmental samples (r = 0.57; p \u3c 0.001). The environmental samples tested (n=185) were negative for Coccidioides DNA. While airborne Coccidioides was not detected at the sampling sites and timeframe of this study, the potential for exposure still exists. This study underscores the need to further understand the environmental distribution of Coccidioides species in Las Vegas, Nevada and its implications for public health. The methodology developed in this study can be used to detect environmental fungi, measure outdoor fungal concentrations, and enhance indoor and outdoor air quality surveillance of microorganisms for public health assessment by providing rapid and quantitative results
A Comparative Study of Music Between Mongolia and the Mongolian Ethnic Minority in China: Cultural Backgrounds, Musical Styles, and Modern Developments
No full textThis thesis conducts a comparative study of Mongolian music traditions as they have developed both within Mongolia and among the Mongolian ethnic minority in China, exploring their cultural backgrounds, musical styles, and contemporary developments. By investigating the historical, geographical, and socio-cultural influences that shape the music in these regions, this study highlights the unique musical identities of each group while uncovering their commonalities and cultural exchanges. Drawing from a wide range of sources—including ethnographic studies and analysis of specific musical pieces—this research examines foundational elements such as the Mongolian long song, throat singing, and horsehead fiddle music. These traditional forms are contextualized alongside contemporary fusion efforts by modern Mongolian bands, showcasing the blend of traditional techniques with modern genres.A central focus of this study is the exploration of how regional and cultural distinctions influence the music’s thematic and structural elements, specifically examining how ethnic and cultural identity is expressed through music. This is achieved through case studies of key musical works and operas, including the Mongolian opera Three Sad Hills and the Chinese national opera The White-Haired Girl, as well as traditional and modern songs such as “Three Chestnut Horses” and “Father’s Prairie, Mother’s River.” Additionally, the thesis addresses the impact of globalization on traditional Mongolian music, investigating the preservation efforts and adaptations occurring in both Mongolia and China. Policy support, cultural exchange programs, and societal engagement are discussed as crucial elements in the ongoing preservation and promotion of Mongolian music in the modern world. By offering a comprehensive analysis of these themes, this thesis contributes to the broader field of ethnic music studies and emphasizes the significance of preserving and understanding Mongolian musical heritage as a means of fostering cross-cultural appreciation and identity continuity
The Miseducation of Taylor Cummings: An Autoethnographic Analysis of Belonging in The United States Education System and A Vision Towards Healing and Consciousness
No full textThis autoethnographic study examines my lived experiences navigating the U.S. education system as a Black girl becoming a Black woman. From an African-centered perspective (Asante, 1990) this study critiques how belonging and motivation are conceptualized through Eurocentric frameworks that lead to conceptual incarceration, epistemicide, and the miseducation of Black students. Using Blackgirl Autoethnography (Boylorn, 2016) and Intuitive Inquiry (Anderson, 2004; Romanyshyn, 2007), I constructed a Life Timeline (Bau, 2024) from archival artifacts, academic and medical records, personal journals, and conversations with family and educational mentors. This allowed for a deeper understanding of how institutional exclusion, religious indoctrination, and psychological misorientation shaped my understanding of identity, motivation, and belonging. Data were analyzed using The Soundtrack of My Life (Payton, 2023), functioning as a hermeneutic and analytical tool. Through lyrical interpretation, I examined how music gave voice to emotional truths, ancestral memory, and unspoken resistance. Findings reveal that institutional belonging often required fragmentation of self, while a true sense belonging emerged through (re) connection with self, my cultural heritage, and deep, soul work—most notably through an episode of psychosis reinterpreted as a spiritual awakening. This study calls for a (re)conceptualization of motivation and belonging as intuitive, communal, and rooted in African-centered onto-epistemologies. In doing so, it urges Educational Psychology to expand its frameworks to affirm the spiritual, emotional, and cultural dimensions of Black life
Gaming Participation: An Occupational Therapy Approach to Esports Ergonomics
No full textCompetitive e-sport gamers are increasingly at risk for repetitive strain injuries (RSIs) due to the prolonged and repetitive nature of their gaming demands. Current healthcare protocols often overlook the unique ergonomic needs of this population, potentially leading to decreased occupational performance and dysfunction. This study aims to develop and evaluate an evidence-based ergonomic protocol tailored specifically to e-sport gamers who primarily use a mouse and keyboard, with the goal of reducing the risk of musculoskeletal injuries and enhancing gaming performance. Grounded in the principles of occupational therapy, the study emphasizes occupation-based interventions that address the specific occupational demands of e-sport gamers. Using a quasi-experimental convergent mixed methods design, the study will be conducted over the span of 6 weeks, involving esports athletes aged 18 to 30. Quantitative data on gaming performance and ergonomic risk factors was collected using Kovaaks software and the Rapid Entire Body Assessment (REBA), while qualitative insight was gathered through a focus group interview. It is hypothesized that the implementation of the ergonomic protocol will lead to improved posture, decreased muscle tension, and enhanced gaming performance. The findings of this study will contribute to the advancement of occupational therapy practice by providing targeted, occupation-based interventions that promote the health, well-being, and occupational performance of esports athletes
Routine Activity Theory and the Severity of Terrorist Act
No full textTerrorist incidents have increased dramatically in the past several decades, leading to significant casualties and property damage worldwide. While prior studies grounded in lifestyle exposure theory have explored how victim demographics, lifestyle, and routine activities influence the likelihood of victimization, this study applies Routine Activity Theory to examine whether increased guardianship in the form of target security reduces the severity of terrorist incidents. Using data from 15,138 terrorist incidents in 2015 from the Global Terrorism Database (GTD), this study investigates the relationship between offender motives, target security, and the severity of attacks, measured by fatalities, injuries, and property damage. Furthermore, it assesses regional variations in these relationships to determine whether the impact of target security on attack severity differs across geographic contexts. By explicitly testing whether higher levels of security mitigate attack severity, this study contributes to the theoretical development of Routine Activity Theory in terrorism research. It offers insights for designing effective counterterrorism strategies
Autonomous UAV Swarm Formation Utilizing Gradient-Driven Contour Mapping for Radiation Source Localization
No full textThis thesis presents a drone swarm for radiation mapping to aid source localization. The Department of Energy advocates employing UAVs for this task, but existing approaches remain inefficient and impractical in real-world scenarios. Three custom drones are built and flight-tested. A control algorithm to follow a contour, a constant-intensity path, is designed using a gradient fit. By knowing the source’s direction, the drone swarm can fly in the optimal trajectory at every step, leaving nothing to assumption. A program is created that implements formation flight and autonomous navigation. It is tested via a software-in-the-loop simulation utilizing radiation sources and detectors modeled on their physical counterparts. Configurable missions are created to demonstrate contours for varying numbers of sources, relative locations, and strengths. The swarm, flying within a physics engine and using drones running production firmware, achieves contour mapping accuracy, efficiency, and reliability that surpass even purely theoretical results. Its detailed modular design simplifies physical deployment and enables extension to nonradiative signals
Morphological and Transcriptional Responses of Mammalian Cells to Glucose Stress
No full textOrganismal cells encounter varying conditions, including daily and potentially seasonal fluctuations in available glucose. While some species tightly regulate circulating glucose levels, others tolerate extreme fluctuations, such as frugivorous bats experiencing post-prandial hyperglycemia and hibernating mammals maintaining stable glucose through torpor and hibernation. To investigate how these species-specific strategies influence cellular responses to glucose perturbation, primary dermal fibroblasts from nine mammals – humans, rats, Egyptian fruit bats, brown bear, 13-lined ground squirrel, little brown bat, gelada, honey badger, and Bactrian camel – were exposed to hypoglycemic (2.5mM), baseline (8mM), or hyperglycemic (30mM) treatment. Cell morphology was evaluated using Cell Painting, a high-content imaging approach that labeled the nucleus, actin cytoskeleton, and ER. Morphological features, including size, shape, intensity, texture, and nuclear-to-actin ratio, were extracted using CellProfiler. Distinct species-specific remodeling patterns emerged. Glucose-sensitive species, including humans and rats, showed coordinated reductions in nuclear and cytoskeletal size under high-glucose stress, while glucose-tolerant species such as fruit bats exhibited minimal morphological disruption. To complement this phenotypic data, transcriptome analysis was performed using RNA sequencing across all glucose treatments in humans, rats, Egyptian fruit bats, little brown bats, and 13-lined ground squirrels. Differential gene expression analysis revealed conserved and species-specific patterns. Glucose-sensitive species, such as humans and rats, exhibited broad activation of inflammatory, oxidative stress, and metabolic regulatory pathways under glucose stress, whereas glucose-tolerant species like fruit bats exhibited extensive but controlled transcriptional changes consistent with metabolic flexibility. Together, these results provide a comparative framework for understanding how mammals manage glucose-induced cellular stress. The integration of morphological and transcriptomic data highlights both convergent and divergent strategies of cellular glucose regulation, offering insights into the evolutionary plasticity of metabolic homeostasis and its relevance to metabolic disorders such as diabetes
Latinx Aspiring Teachers at Hispanic Serving Institutions: A Latcrit Narrative Inquiry
No full textAcross the United States (U.S), Latinx students comprise the largest ethnic student demographic in K-12 schools, yet they remain significantly underrepresented in the teaching profession, constituting less than 10% of the teacher workforce. This disparity highlights the urgent need to examine how they persist through the Latinx teacher pipeline, to enter the teaching profession. Teacher education programs, particularly those housed within Hispanic Serving Institutions (HSIs), play a critical role in the recruitment, preparation, and retention of Latinx aspiring teachers. This qualitative study employed a critical narrative inquiry methodology to explore the racialized experiences of Latinx aspiring teachers at an HSI in the Mountain West region. Grounded in Critical Race Theory (CRT) tenets and Latina/o Critical Race Theory (LatCrit), the study examined Latinx aspiring teachers’ personal, academic, and social experiences as they navigated an education major. All nine aspiring Latinx teachers participated a brief demographic survey and one in-depth interview. The analysis included a restorying process using specific tenets that derived from CRT, CRT in education and LatCrit. Findings reveal the multiple forms of systemic oppression, and institutional marginalization these students encountered, as well as the familial support systems that sustained their persistence.Overall, this study filled a gap in the existing body of research related to undergraduate Latinx aspiring teachers at an HSI. Specifically, the experiences of undocumented aspiring teachers at HSIs. Additionally, this study also contributes to the existing research on the Latinx Teacher Pipeline. This study underscores and recommends the need for teacher education programs at HSIs to adopt more culturally sustaining and critically conscious practices to better prepare and support Latinx aspiring teachers
The Dropbot: Design and Development of a Custom Drone for Precision Water Drop Penetration Time (WDPT) Testing
No full textAssessing the hydrophobic characteristics of soil is vital for understanding soil wettability or soil-water interactions, particularly in post-wildfire environments where water repellency can significantly impact ecosystem recovery, water infiltration, and erosion control. One key metric in soil wettability studies is the Water Drop Penetration Time (WDPT) test, which evaluates the hydrophobicity of soil and guides land treatment strategies. This thesis presents the design and development of DropBot, a custom-built drone platform engineered for the precise delivery and analysis of water droplets in WDPT tests.The DropBot, a custom drone, integrates a lightweight, 3D-printed frame with a self-leveling platform, enabling consistent droplet deployment and testing across varied terrains. The system is equipped with modular manipulators, a custom droplet release mechanism, and multiple onboard sensors for environmental feedback. The DropBot is operated using the Robot Operating System (ROS) framework, allowing for scalable sensor integration, data acquisition, and autonomous behavior. The development process included iterative mechanical design, sensor calibration, and field testing to ensure precision, stability, and repeatability. Experimental results demonstrate the DropBot’s ability to accurately deliver water droplets with controlled positioning and timing, validating its utility for in-situ WDPT tests. This work also contributes to the growing field of agricultural robotics and sets the stage for further enhancements, such as computer vision integration for surface detection and fully autonomous mission planning for soil property mapping