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The Impact of Intimate Partner Violence on Young Mother\u27s Mental Health
No full textIntimate partner violence (IPV) rates are notably higher among adolescents who are pregnant or have experienced a pregnancy, with physical IPV reaching up to 62%, and psychological abuse being even more common. IPV has serious mental health consequences for adolescent mothers, leading to increased rates of depression and anxiety which can impair caregiving. IPV negatively affects children, increasing the risks of poor maternal bonding, and low birth weight. This study investigates how IPV contributes to adverse mental health outcomes in Brazilian adolescent mothers. A cross-sectional approach was used with data collected between August 2023 to 2024. The study participants were adolescent mothers under 20 years old, with children aged 0 to 5 years, residing in southern Brazil. Research assistants collected data following approval from the Institutional Review Boards (IRB) of UNLV and a partner university in Brazil. The study utilized Fisher\u27s exact test to analyze correlations between mothers\u27 responses to IPV-related questions and their mental health symptoms, as measured by the DASS-21 screening tool. 55.45% of participants who reported experiencing emotional IPV also exhibited moderate to severe depressive symptoms, with a significant correlation between the variables (P \u3c 0.001). Physical IPV was correlated with depressive symptoms (P = 0.01), with 50% of young mothers reporting both experiences. Experiencing IPV at a young age can deteriorate the physical health of an adolescent mother but also increase the likelihood of developing a mental illness. It is important to provide screenings for IPV and mental health to improve the well-being of all mothers.https://oasis.library.unlv.edu/durep_posters/1211/thumbnail.jp
Investigating a Mediterranean Dietary Pattern With White Potatoes on Cardiometabolic Health in Adults With Pre-diabetes From Diverse Racial and Ethnic Backgrounds
No full textIn the United States, one in three adults has pre-diabetes, and 80% are unaware that they are at risk of developing type-2 diabetes (T2D). Elevated blood glucose levels are associated with an increased risk of heart disease, obesity, dyslipidemia, and hypertension. African-American and Hispanic individuals are disproportionately affected by pre-diabetes and its complications, such as arterial stiffness and obesity, compared to Caucasians. Approximately 70% of those with pre-diabetes may develop T2D, therefore it is crucial to find effective ways to manage and reverse these conditions. Potatoes, which contain a good source of resistant starch, potassium, and other beneficial nutrients, might help improve blood glucose control and heart health. Studies have shown that potatoes, especially with their skin, can improve insulin sensitivity, satiety, and cholesterol levels. However, minority groups in the U.S. tend to eat fewer potatoes compared to Caucasians. Combining potatoes with nutrition education focusing on the Mediterranean diet, could be a practical approach to improving blood glucose levels, heart health, and overall diet quality in people with pre-diabetes. This study aims to explore the effects of incorporating baked potatoes with skin, alongside nutrition education focusing on the Mediterranean Dietary Pattern, in diverse racial and ethnic groups with pre-diabetes.https://oasis.library.unlv.edu/durep_posters/1224/thumbnail.jp
The Effects of Divides Attention on Long-term Memory for Natualistic Stimuli
No full textThe ability to identify previously experienced events is a fundamental aspect of memory. This study investigates recognition memory using naturalistic stimuli, specifically news headlines, to explore both controlled (recollection) and automatic (familiarity) memory processes. Most recognition memory experiments rely on simplistic stimuli like words or pictures, but we aim to extend these theories by using more complex, naturalistic materials (news headlines). Participants completed recognition tasks with both headlines and pictures to establish baseline differences between these stimuli types. The order of presentation between stimulus types was randomized between pictures or headlines first. They were assigned to either full or divided attention conditions during study, with the divided attention group completing an n-back task while encoding headlines. After encoding, participants listened to a podcast and answered questions about it to introduce a delay between taking an old/new recognition memory test. Recollection and familiarity estimates were calculated using the Dual Process Signal Detection model. Previous research has found that dividing attention has been shown to have large effects on estimates of recollection, whereas familiarity typically shows smaller or no effects. Preliminary results indicate that estimates of both recollection and familiarity were higher for headlines compared to pictures across both attention conditions. These findings highlight the need for further research on naturalistic stimuli, including long-form media such as music, podcasts, movies.https://oasis.library.unlv.edu/durep_posters/1233/thumbnail.jp
Development of Uranium Fluoride Microstructures
No full textUranium microstructured materials with controlled size and shape have found applications in several branches of the nuclear industry including as targets for medical isotopes production, fuels for nuclear reactors, standards for analytical measurements, and energy sources for space exploration. Morphological studies of actinide materials are also highly relevant to nuclear forensics-related work. Other potential applications include information storage, catalysis, sensors, and luminescent devices. Most studies on uranium microstructured materials have focused on binary oxides, nitrides, carbides, and fluorides, with the spherical shape being the dominant morphology. Prior to the work reported in this dissertation, aside from UF4 microspheres (ms) and UF4(H2O)2.5 microrods (mr), uranium halide or oxyhalide micromaterials with controlled morphologies (microspheres, microrods, microplates (mp)) have not been reported. This paucity provides an opportunity for the development of novel materials with tunable catalytic and spectroscopic properties, as well as new nuclear fuels with increased gas retention and target materials with specific release rates of isotopes. Due to the preponderance of uranium and fluorine in the nuclear industry, investigation into the preparation of uranium fluoride micromaterials is of interest.
A promising method to tailor micromaterials with controlled chemical composition, morphology, and size is chemical transformation. Chemical transformations are reactions performed on microscale materials to selectively modify their chemical composition, crystal structure and/or morphology. In this work, the chemical transformation investigated is the replacement of oxygen by fluorine atoms in oxide materials using a solid-gas reaction. The elaboration of uranium fluoride micromaterials from the fluorination of uranium oxides (U3O8 and UO2) microspheres, microrods, and microplates in autoclaves with in-situ HFg (produced from the thermal decomposition of silver bifluoride and ammonium bifluoride) has been fully demonstrated. By chemically transforming these uranium oxides into uranium (IV) and uranium (VI) fluorides while retaining morphology, several new micromaterials (i.e., (NH4)3UO2F5 ms/mr/mp, (NH4)xUFx+4 ms, UO2F2 mr/mp, and UF4 mp) were prepared for the first time. The materials were characterized by powder x-ray diffraction and scanning electron microscopy. The successful preparation of uranium fluorides ms, mp and mr presented here can pave the way for the development of other f-element fluoride micromaterials
UVC and Planetary Habitability: Insights from Desert Lichens and Cyanobacteria
No full textAn important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to three months of UVC exposure. Additionally, two of the study organisms, colonial cyanobacterium and cyanolichen, were irradiated for nine days under metabolically active conditions (hydrated and under visible light) to UVC fluxes found on Archean Earth. The hydrated exposure resulted in a significant decline in photosynthetic activity in the colonial cyanobacterium after just one day; however, the cyanolichen showed no reduction in activity throughout the nine-day experiment. These survival results under both dry and wet irradiation, combined with further experiments to understand the source of UVC injury to lichens, suggest that surviving under high UVC fluxes may not be an issue for life. Future work studying the growth and reproduction potential of these organisms could suggest that the surface of Mars and exoplanets are not necessarily uninhabitable just because they are exposed to UVC radiation
From Extraction to Attraction: Case Studies in Historic Preservation, Heritage Tourism and Interpretation, 1945-2010
No full text“From Extraction to Attraction: Case Studies in Historic Preservation, Heritage Tourism and Interpretation” examines four interpretive sites in Nevada—Virginia City, the Springs Preserve, Spring Mountain Ranch State Park, and Walking Box Ranch—to explore tensions over shared authority at these significant public history sites and landscapes. Nevada’s economy and environment, historically shaped by mining, ranching, and military activities, underwent a transformation with the decline of extractive industries and the rise of tourism. This transition affected the use, management, and preservation of public lands, with tourism becoming the primary identity. These changes presented challenges and opportunities for environmental advocates and public historians who wished to interpret and preserve critical sites and landscapes. This dissertation uses interpretive sites to link geographically diverse attractions that share a history of complex relationships between tourism, federal land management policies, cultural sovereignty, and environmental preservation. Each site reflects important changes in perceptions of the desert landscapes and demonstrates the tensions between various stakeholders, including federal agencies, miners, ranchers, and local communities as they collaborated and contested the fate of these historic sites. This dissertation explores the concept of shared authority in public history, where stakeholders collaborate and contest interpretive narratives. Shared authority underlies the interpretation and meaning making of objects, sites, or historical figures. It is inherent in how stakeholders understand and interact with interpretive sites. It analyzes how relationships with land management agencies and changing views on public use and access influenced Nevada\u27s public history landscape. In examining shared authority reveals that it is often unequal among stakeholders, with tensions surrounding whose interpretation of the historic site and land use takes priority. Overall, shared authority is often aspirational, and public historians should strive to achieve more equal authority at these sites. By exploring these case studies, the dissertation addresses key questions about Nevada’s history, including the role of evolution of “one-industry economies,” the influence of federal agencies like the Bureau of Land Management (BLM) on that process, and the significance of the regionally specific environmental context for each of these interpretive site case studies. Each of these case studies serves as an excellent example for public history practice as it evolved in the twentieth century and as it is practiced today. By better revealing the context for historic preservation efforts in these four Nevada case studies this dissertation provides new insights on the relationships between tourism, federal land management policies, and contested desert environment
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
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
Probing the Ecological Functions of Thermophiles Using Cultivation-Dependent and Cultivation-Independent Techniques
No full textHigh-temperature geothermal springs are ecosystems that resemble early Earth, offering insights into the origins and early evolution of life. In these unique ecosystems, thermophilic microorganisms thrive. However, our knowledge of thermophiles remains limited. A major challenge is that many thermophiles remain uncultivated. The primary goal of this dissertation was to explore the diversity, metabolism, and ecological functions of thermophiles using cultivation-dependent and cultivation-independent approaches. Chapter 1 provides a broad overview of geothermal spring ecosystems and thermophiles, along with a roadmap of the dissertation. Chapter 2 documents a study on the response of specific thermophiles from Gongxiaoshe (GXS) Hot Spring in China to pulses of labile dissolved organic carbon, specifically acetate and aspartate, using quantitative stable isotope probing (qSIP) and metagenomics. The results indicate strong resource partitioning and a wider preference for aspartate incorporation into DNA over acetate. Chapter 3 explores the ecophysiology and evolution of a dominant archaeal species, designated Calditenuis ramacidaminiphagus, from Great Boiling Spring, Nevada, USA. By using fluorescence in situ hybridization coupled with nanoscale secondary ion mass spectrometry (FISH-NanoSIMS), metagenomics, metaproteomics, and laboratory cultures, we demonstrated branched-chain amino acids (BCAAs) specialization in C. ramacidaminiphagus. We also showed that BCAA specialization as a key trait for the genus Calditenuis. Chapter 4 summarizes our research findings and discusses future research perspectives. Chapter 5 describes my contributions to other research projects
Kicking the Robots: The Roles of Transformational Leadership and Fear on Service Robot Risk Awareness and Robot Abuse Relationship
No full textPurpose: Service robots are increasingly prevalent in the hospitality industry. While studies have explored the concept of service robot risk awareness (SRRA)– an employee’s perception of service robots posing a threat to human labor– the impact of SRRA on robot abuse and its emotional mechanism through which it affects employees remains unclear. This research leverages emotional appraisal theory to investigate the mediating role of fear of robots in the relationship between SRRA and robot abuse. Additionally, considering the influential role of leadership in shaping emotional appraisal, this study examines the moderating impact of transformational leadership.
Design/Methodology/Approach: To test the proposed model, time-lagged survey data were collected from 283 employees working under 54 leaders in 18 hotels in China. The model was analyzed using multilevel modeling in Mplus 7.3.
Findings: At the individual level, SRRA indirectly increases robot abuse through the mediation of fear of robots. However, there is a cross-level moderation: the indirect relationship is alleviated when leaders exhibit high levels of transformational leadership.
Originality/Value: This study pioneers the concept of robot abuse in hospitality and tourism settings. It extends emotional appraisal theory by highlighting the significant mediating role played by fear of robots. Furthermore, demonstrating how transformational leadership can mitigate the effects of SRRA offers valuable insights for leadership selection and training to facilitate the successful implementation of service robots