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Incarcerated Nations: Confinement, Removal, and Policing on the Colorado River Indian Reservation
No full textThe United States incarcerates more people than any country in the world. The nation\u27s prisons and jails hold more than 2.1 million inmates, and U.S. Immigration and Customs Enforcement detains another 500,000 annually. Before the Covid-19 pandemic, U.S. taxpayers paid approximately $85 billion per year to cover the cost of mass incarceration in prisons and jails. This economic burden does not include the added expenses borne by families and communities who lose members to prison along with their potential earnings. Scholars often attribute the expansion in American incarceration to the War on Drugs and identify African Americans as the most prominent victims of unjust systems of imprisonment. However, Indigenous Peoples experienced mass incarceration long before the 1980s. American policies removed Indigenous Peoples from sacred homelands to reservations led by Indian agents who intended to alter traditional lifeways. Federal Indian policy imprisoned, impoverished, and surveilled Indigenous Peoples. Removal and reservation policies created long-standing carceral practices justified as necessary within the United States. Removing and incarcerating Indigenous Peoples made land and resources available to American settlers. However, Americans have often overlooked these practices when considering mass incarceration, even though Indigenous Peoples continue to be disproportionately imprisoned compared to other ethnic groups in the United States. By considering how and why the United States imprisoned Indigenous People, this dissertation elucidates the normalization of mass incarceration and explains how settler colonial projects targeting Indigenous Peoples established carceral structures that continue to affect Americans today. An analysis of the Colorado River Indian Tribes provides the ideal setting to interrogate the detention policies of the United States and the role of settler colonialism in the mass incarceration of Indigenous Peoples
The Influence of the COVID-19 Pandemic on Binge Eating in a Demographically Diverse US Community Sample
No full textThe novel coronavirus pandemic (COVID-19) has had profound effects among many individuals with or at risk for eating disorders. The most common primary eating disorder is binge eating disorder which has uniquely reflected more similarities than differences among diverse populations compared to other eating disorder classifications. Considering the upsurge of prevalence rates of eating disorders during the pandemic, it is important to assess the rate of binge eating across the demographic strata to gain a better understanding of who is impacted and provide healing to those who are suffering. Screening for binge eating features across the United States (US) using validated measures is a critical first step for this undertaking. The current study examined exploratory and confirmatory factor analysis as well as measurement invariance of the Binge Eating Disorder Screener-7 (BEDS-7) across gender and sexual orientation, the prevalence of binge eating and co-occurring psychopathology (e.g., depression, anxiety, sexual trauma, alcohol use severity), and the moderating effects of COVID-19 pandemic stress and perceived degree of social support on binge eating and areas of psychopathology. Participants included a large and diverse US community sample of men and women across various demographic profiles (i.e., gender, age, socioeconomic status, race/ethnicity, sexual orientation). I first conducted exploratory factory analysis (EFA) to examine the factor structure of the BEDS-7, followed by confirmatory factor analysis (CFA) to verify the factor structure and establish the configural model. Next, I explored measurement invariance with the configural model by gender and sexual orientation. CFA supported a one-factor, six-item measure reflecting binge eating features. The BEDS-7 was noninvariant across gender and sexual orientation, thus a total score measuring overall features of binge eating was used in subsequent analyses. Cisgender women and those who identified as belonging to a gender minority reported higher binge eating features than cisgender men. Individuals belonging to a sexual minority group reported higher means of binge eating relative to heterosexual participants. The prevalence of binge eating features decreased as age increased. Those with lower than a college degree endorsed higher means of binge eating relative to those with a university degree. COVID-19 pandemic stress was associated with binge eating features; however, COVID19 pandemic stress did not serve as a significant moderator between psychopathology and binge eating features. Similarly, perceived social support indicated a negatively significant association with binge eating features but did not have a buffering effect between binge eating and psychopathology. Lastly, lack of perceived social support indicated a positive association between binge eating, however, did not moderate the association between binge eating and psychopathology. Taken together, screening of binge eating features in the community, such as in healthcare settings, may promote early identification of binge eating features who could then be referred for further evaluation and intervention
The Role of Surfactant Adsorption in Boiling Dynamics
No full textBoiling processes play a substantial role in numerous commercial and industrial sectors, including electronic components, avionics, power plants, cooling systems, and water purification centers, for thermal management. The efficient heat transfer mechanism and high latent heat of evaporation inherent in water contribute significantly to bubble formation during boiling. Despite being widely employed as a heat transfer process, enhancing boiling presents challenges due to its non-equilibrium, dynamic, and unpredictable nature. One effective method to improve boiling heat transfer is through the use of surfactants. When added and dissolved in water, surfactants modify the liquid-solid and liquid-vapor interfacial properties, thereby altering boiling behavior, including bubble size, nucleation site density, departure frequency, and non-coalescence. Previous studies have indicated that surfactants are most effective in boiling water near the critical micelle concentration (CMC), a property in equilibrium that depends on the type of surfactant. However, conventional wisdom studies have primarily investigated a limited number of surfactants across narrow molar concentration ranges. The work presented in this dissertation broadens the scope by examining a wide array of ionic and nonionic surfactants over a wide concentration range. Surprisingly, we have discovered an optimal concentration range that operates independently of the critical micelle concentration (CMC). Our findings unveil that the effectiveness of surfactant-enhanced boiling is governed by two opposing factors: the dynamic adsorption of surfactants to interfaces and the increase of liquid dynamic viscosity at exceedingly high surfactant concentrations. Furthermore, this dissertation illustrates that dynamic adsorption operates as a diffusion transport-limited behavior, contending within a limited time window of a bubble lifetime and the timescale of diffusion necessary for surfactant adsorption to interfaces. With the right interplay between these two timescales, changes in boiling behavior are synchronous, quantified through the heat transfer coefficient (HTC) and the critical heat flux (CHF). This phenomenon unveils an HTC-CHF trade-off behavior, regardless of the surfactant type. Furthermore, we evaluate whether ionic liquid-based surfactants (ILBSs) of different chain lengths could break in the HTC-CHF trade-off behavior, as reported in recent literature. Overall, the results presented in this dissertation challenge conventional wisdom in the field, providing a fresh, practical perspective on how surfactants enhance the efficiency of boiling systems with the right amount of surfactant additives in the fluid. We also established general correlations to predict changes in aqueous surfactant boiling heat transfer. This novel scientific approach is applicable for any type of surfactant across a wide range of systems that rely on a boiling process to optimize heat transfer, particularly in energy-centric applications using surfactants, thus offering a new practical method to predict changes in aqueous surfactant
Non-Contact Acoustic Emission Detection of Rail Defects Using Air-Coupled Sensors
No full textRail defects, whether internal or external, present significant safety risks. Acoustic Emission (AE) technology has emerged as a promising technique for monitoring damage progression and detecting these rail defects. This project addresses this critical concern by testing air-coupled optical microphones for non-contact AE detection. The goal of this research is to investigate AE signal characteristics using both rail-mounted and vehicle-mounted methods, establishing the understanding of AE signals in relation to defects and their effectiveness in identifying them.
This research focused on investigating air-conduct sensors in the lab-controlled pencil lead break (PLB) test. The objective was to evaluate the propagation characteristics of AE signals in two scenarios: signal attenuation in the air and within the rail. These tests were particularly designed to assess the prototype\u27s performance under varying conditions, including different speeds and defect types. Following the controlled experiments, the research conducted real-world field tests at two different test locations: the Nevada Railroad Museum and the MxV Rail (formerly known as the Transportation Technology Center, Inc (TTCI)). These sites offered diverse testing conditions, allowing for a broader evaluation of the system capability. Data collected from all tests were analyzed to assess the effectiveness of the system, when mounted on a moving train to detect both internal and external rail defects.
The result of both tests revealed two key findings. First, the AE detection rate varied significantly between tests, with a rate of 8.3% in the Nevada field test and 13.3% in the MxV Rail test. This difference suggests that AE detection rates may be influenced by defect size and conditions in the field environment. Second, wavelet packet power (WPP) analysis highlighted substantial differences between PLB-induced AE signals and those from actual rail defects. While PLB signals displayed broader energy distribution across the frequency range, the AE signals from rail defects exhibited concentrated and intense peaks within the 100-160 kHz range.
Overall, the non-contact sensor system demonstrated promise for detecting internal rail defects, effectively capturing AE signals without disrupting train operations, making it suitable for real-time rail health monitoring. However, the detection of external defects demonstrated low performance due to indistinct AE signal characteristics (compared with internal defect induced AE signals) and significant environmental noise. The application of continuous wavelet transforms (CWT), and wavelet packet power (WPP) analysis presented more results by identifying energy distributions and frequency peaks associated with defect types. Although these methods enhanced the detection of external defects, additional research is required to refine the identification process.
In conclusion, these findings offer valuable insights into developing more effective and reliable AE-based monitoring solutions. They highlight the current capabilities of these systems in detecting different types of defects, ultimately contributing to improved railway safety and maintenance efficiency
Canine Parasites in Southern Nevada Urban Dog Parks: Paravec Study
No full textWhile dogs are one of humans’ greatest companions, they also serve as hosts for a multitude of parasites. Urban dog parks serve as environments where the transmission of diseases is likely to occur. Exposure to infective agents, contained within the soil, intermediate hosts (e.g., rodents, rabbits), and feces, can directly affect the health of dogs and their owners. Other factors that can further influence canine health include age, previous diagnoses of parasites/diseases, and migration. Many dog owners visit dog parks to encourage socialization and exercise. Such activities are meant to improve health, but unawareness of microbiological organisms can lead to detrimental health conditions if not prevented and treated at the early stages. Human populations, such as children, the elderly, pregnant women, and immunocompromised individuals, who are exposed to certain species of protozoa, helminths, and other parasites, may develop physical and neurological damage. In this study, n = 100 fecal samples from 16 Clark County, NV urban dog parks were collected from canine pets. After laboratory processing using fecal smear and fecal flotation procedures (i.e., sugar and salt), and microscopic observations, we found that canine parasites were present in n=50 (50%) of stool samples. Out of those that were observed, protozoan, nematode, and cestode species were identified, most of which have zoonotic potential. It is important that public health professionals encourage communities to monitor their pets’ health. For instance, appropriate vaccination, routine veterinary checkups, and proper hygienic practices can reduce the risk of transmission
Early Childhood Teacher Knowledge: Distinguishing Between Developmentally Appropriate Behavior and Maladaptive Behavior
No full textThis dissertation investigates the effectiveness of a professional development program aimed at enhancing early childhood education (ECE) teachers\u27 abilities to identify and address developmentally appropriate versus maladaptive behaviors in young children. Utilizing an explanatory sequential mixed methods design, the study involves pre- and post-intervention surveys, a post-intervention focus group, and the implementation of four asynchronous learning modules. The participants, pre-service teachers from a large urban university, were evaluated on their knowledge and application of distinguishing between behaviors in early childhood settings.The literature review highlights the struggles ECE teachers face in identifying maladaptive behaviors and the need for targeted professional development. The professional development content was derived from Wakschlag and colleagues\u27 work on behavior dimensions and included the use of Content Acquisition Podcasts (CAPs) as an innovative educational tool. The results indicate slight improvements in teachers\u27 knowledge and their ability to apply this knowledge in practical settings. This study contributes to the field by providing evidence on the effectiveness of CAPs and other structured professional development frameworks in ECE. The findings suggest that improving teacher training can lead to better early interventions, thereby mitigating long-term negative outcomes associated with maladaptive behaviors in young children. The study also identifies areas for future research, including the need for ongoing support and training for ECE teachers in behavior management
Gender Stereotyping in an Agricultural Sample
No full textA vast wealth of social psychological research conducted over half a century has demonstrated the consequences of gender stereotypes. However, this research has significant limitations. Namely, generalizability outside of academia and the effects of social change. This study examined a non-academic population that has recently experienced significant gender role redistribution to overcome these limitations. Utilizing a full-cycle research approach consisting of both ethnographic and experimental methods, I examined three research questions: 1) how do gender stereotypes manifest within rural agricultural communities? 2) how is women’s increased participation in agriculture related to changes in gender stereotype use? and 3) how do gender stereotypes in rural, agricultural samples compare to gender stereotypes in urban, university samples? The results of this study provide evidence supporting the development of more comprehensive and inclusive gender stereotyping measures, contribute to scientific knowledge about the variables affecting gender stereotype use, and provide insight into the benefits of examining subcultures in gender stereotyping research
Formation Potential of Disinfection Byproducts from Quaternary Ammonium Surfactants During Ozonation with Subsequent Chlor(am)ination
No full textQuaternary ammonium-based surfactants (QAS) are ubiquitous in daily life, found in products ranging from disinfectants and fabric softeners to food preservatives and personal care products. Their widespread use, especially during the COVID-19 pandemic due to their antimicrobial properties, has made them indispensable in modern hygiene and public health practices. However, their prevalence is not without concerns. When these compounds enter wastewater treatment plants, they are not fully degraded by the conventional treatment methods used, due to variations in their structural properties. As a result, QAS residues persist and accumulate in treated wastewater effluents, ultimately affecting water sources. These residues end up in water treatment plants where they are transformed into potentially harmful disinfection byproducts (DBPs) through methods such as ozonation and subsequent chlorination/chloramination.This necessitated a comprehensive investigation into the reaction of these compounds with common water treatment disinfectants including chlorine, monochloramine, and ozone. This study examined the formation potential of disinfection byproducts (DBPs) namely haloacetic acids (HAAs), haloacetonitriles (HANs), N-nitrosamines (NOAs), and trihalomethanes (THMs) from ten distinct quaternary ammonium-based surfactants (QAS) including allyltrimethyl ammonium chloride (ATMAC), benzalkonium chloride (BAC), benzethonium chloride (BTC), cetylpyridinium chloride monohydrate (CPC), Cetyltrimethylammonium chloride (CTMAC), diallyldimethyl ammonium chloride (DDAC), dodecyltrimethylammonium chloride (DTMA), didecyldimethylammonium chloride (DDEC), polydiallyldimethylammonium chloride solution (polyDADMAC), tetramethylammonium chloride (TMAC). These compounds were selected based on their prevalent use in commonly available consumer products and structural variations such as the presence or absence of a benzene ring, chain length, and saturation level of the carbon chains. They were prepared to a target concentration of 0.1 mM and subjected to simulated water treatment processes, including chlorination/chloramination, and ozonation followed by chlor(am)ination. Controlled formation potential tests were meticulously conducted at a controlled pH of 7, with precisely targeted residual chlorine concentrations maintained at 1.0±0.4 mg/L as free Cl2 over a three-day period and 2.5±0.5 mg/L as total free Cl2 over five days. The results demonstrated significant increases in the formation of DBPs, particularly HANs, HAAs, and THMs. Notably, DCAN molar yields peaked at 45.6 μmol/mol during chloramination alone and later increased to 479 μmol/mol following ozonation and subsequent chloramination. Similarly, DCAA molar yields ranged from 197 μmol/mol to 750 μmol/mol post-chlorination and from 193 to 1980 μmol/mol after ozonation with subsequent chlorination. Total trihalomethanes (TTHM) displayed a substantial variation, with molar yields ranging from 124 to 6910 μmol/mol post-chlorination, and from 187 μmol/mol to 39000 μmol/mol post-chloramination. A critical observation was the significant enhancement of N-nitrosodimethylamine (NDMA) formation, where molar yields increased to a peak of 5330 μmol/mol during ozonation with subsequent chloramination in compounds containing aromatic ring structures such as BAC, BTC, CPC, and polyDADMAC, compared to a peak of 510 μmol/mol during chloramination alone. This marked increase highlights the catalytic role of ozonation in elevating NDMA formation. Pre-ozonation effectively transformed QAS precursors, reducing their potential to form HAAs and HANs during subsequent chlorination. However, it also increased the reactivity of certain compounds, such as BTC, CPC, and BAC, leading to elevated levels of TCAA, DCAA, and DCAN. These observations highlight the dual role of ozonation in water treatment, demonstrating its capacity to both mitigate and enhance DBP formation under specific conditions. These findings highlight the need for careful management of these compounds prior to their discharge via treated wastewater into the environment to mitigate potential DBP formation during drinking water treatment. The study identifies significant gaps in our understanding of the specific pathways through which QAS transform to form intermediate products that act as DBP precursors, emphasizing the necessity for continuous monitoring and adaptive management in water treatment practices to minimize risks associated with DBP formation from QAS precursors
Preparing Anti-Racist Teachers: A Case Study of Preservice Teachers’ Perceptions of Racism and Program Coherence in Equity-Centered Teacher Preparation
No full textThis case study explored the perceptions preservice teachers had regarding racism in educational contexts, how those perceptions were shaped by their teacher education program, and to what extent their teacher education program had coherence in preparing anti-racist teachers. Within the context of a large, minority serving institution in the Southwest preparing teachers for one of the most racially, linguistically, and socioeconomically diverse districts in the country, the need to prepare anti-racist teachers who are able to recognize and remedy opportunity gaps for multi-marginalized students is evident. Because little research has focused on the perceptions and lived experiences preservice teachers have regarding coherence of their programs in preparing future teachers for equity-centered and opportunity-oriented teaching, teacher preparation programs cannot be sure that what is espoused in the mission and vision statements is being implemented throughout the programs and what is learned by their students. Using frameworks of Critical Race Theory and Opportunity Centered Teaching, this case study sought to understand how preservice teachers perceived the coherence of their program related to equity and how teacher educators modeled and prepared their preservice teachers to enact Opportunity Centered Teaching for the benefit of the diverse students in their future classrooms. Data collection methods included document analysis, semi-structured interviews, and observations of preservice teachers in coursework with teacher educators. Preservice teachers (n = 6) and teacher educators (n = 5) were interviewed. The findings indicate participants who engaged in different contexts (less diverse and more diverse school settings) had a burgeoning awareness of racism even though all spoke in race evasive ways. The findings also indicate that a lack of coherence centered on equity produced preservice teachers who had minimal understandings of how white supremacy culture functions in education and how or why they should enact anti-racist pedagogies. Consequently, elementary preservice teachers were unable to articulate strategies beyond relationship cultivation to increase opportunities for diverse students in their future classrooms
Beyond the Chart: Reflections on Transforming Data into Patient-Centered Care
No full textThe Data, Information, Knowledge, Wisdom (DIKW) Framework is a foundational model in nursing informatics that helps conceptualize how raw data is transformed into meaningful clinical decision-making. At its core, the framework describes four hierarchical levels: data (raw, unprocessed facts), information (organized and contextualized data), knowledge (synthesized information based on experience and evidence), and wisdom (the ability to apply knowledge in practice to achieve the best patient outcomes). In nursing, this framework is particularly valuable because it mirrors the cognitive processes nurses use to assess, interpret, and act on patient information in real-time clinical settings.
Developing critical thinking is a challenge for student nurses as they must learn to move beyond task-based thinking to recognizing patterns, making connections, and anticipating patient needs. Nurses work most closely with patients, continuously gathering and interpreting data from direct interactions. Nurses are at the bedside observing trends over time, integrating subjective cues, and responding dynamically to evolving patient needs. Novice nurses often struggle with information overload, unsure of which data points are most relevant or how to prioritize competing demands in a fast-paced clinical environment. By using the DIKW framework, students gain a structured way to organize and process clinical information, helping them make sense of complex patient cases. This approach bridges the gap between classroom knowledge and real-world application, guiding students toward independent, confident clinical reasoning that leads to better patient care and outcomes.
Using the DIKW framework to explain clinical decisions enhances student nurse clinical reasoning skills by helping them recognize how seemingly isolated data points contribute to a larger clinical picture. For example, a student may document a blood pressure reading of 88/50 mmHg (data). When combined with the patient’s dizziness and recent medication changes, the data become information that suggests hypotension. Drawing on knowledge of pharmacology and fluid balance, the student understands that the patient\u27s antihypertensive medication may need adjustment. Finally, wisdom is demonstrated when the student collaborates with the healthcare team to adjust the care plan, ensuring patient safety. By following this structured thinking process, students develop the ability to critically evaluate patient information rather than relying on memorization or intuition alone.
We hope these reflections on clinical judgement, written by experienced nurses in the masters of nursing program at UNLV, helps student nurses learn to integrate research findings, clinical guidelines, and team-based communication into their decision-making. This approach not only strengthens their ability to navigate complex patient cases but also builds confidence in their clinical judgment. By guiding students through this structured framework, nurse educators equip them with the tools to think like a nurse, ensuring they become competent, reflective, and effective practitioners