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An Educational Toolkit for Addressing Women’s Sexual Health and Activity: Preparation for Occupational Therapists
No full textDespite being an activity of daily living within the scope of Occupational Therapy, issues and concerns related to sexual health are infrequently addressed within practice. This gap is especially prevalent as it relates to women\u27s sexual health and sexual activity specifically. This capstone project evaluated Occupational Therapists\u27 level of knowledge and comfort when discussing sexual activity and women\u27s sexual health. It measured the effectiveness of creating an online educational toolkit to increase knowledge and confidence. The project used a quality improvement approach with pre-and post-test surveys to determine the effectiveness of the educational toolkit to enhance knowledge and confidence in addressing sexual activity and women\u27s sexual health. The results show that the target population showed mixed levels of confidence and knowledge related to sexual health issues and reported that they rarely initiate conversations on the topics. As a result, the topic needs to be addressed more frequently. Additionally, the pre-and post-survey results measured a slight improvement in knowledge and confidence levels. Finally, the post-survey group gave positive feedback on the effectiveness and accessibility of the online toolkit, reporting that it was helpful in facilitating patient discussions. This capstone project demonstrated the need for novel approaches to facilitate conversations on sexual activity and women\u27s health. The educational toolkit successfully increased knowledge, comfort, and facilitated conversations and could serve as one potential approach to this goal. Ultimately, more studies are needed on topics specifically related to women\u27s sexual health and activity
Intersections of Living and Machine Agencies: Art-Based Models of Adaptive Conversation with the More-than-Human World
No full textToday’s AI systems are not built to have reciprocal interplay with their environments and thus they demonstrate little interest in emergence, adaptation or developing mutually productive relationships with the natural world. Is a different kind of AI possible? How can artists contribute to its development? In this essay, I will discuss ways in which the arts might help guide us towards a new kind of AI, built upon adaptive conversation (i.e. shared construction of meaning) with nature. I will discuss how can work with AI while also challenging its prevailing ontology, and even suggest alternative ontologies and epistemologies. I will begin by discussing the development of Beauty, a hybrid machine-microbial artwork by the experimental research collective [phylum] (of which I am a member) that features interactions between an AI system and pattern-forming bacteria. I will then attempt to contextualize the work within the broader history of artistic experimentation with intelligent machines (which date back to the 1950s) and will also discuss how art and intelligent systems offer new zones of negotiation and reciprocity between humans, machines and the more-than-human world
The Characterization of Cooperative String-pullung Behavior in Rats After Exposure to Space Flight Stressors
No full textAstronauts work cooperatively to complete tasks on missions through deep space where they will experience stressors, including radiation and sleep fragmentation, that may impair performance. Animals work together to achieve a common goal during cooperative tasks using string-pulling behaviors. While string-pulling behavior has revealed deficits in rat sensorimotor function after exposure to space flight stressors, it has yet to be determined if rats will engage in cooperative string-pulling or if these stressors will influence cooperation. Thus, to explore how space flight stressors impact cooperative behavior, female Wistar rats were exposed to either sham (n = 8) or 10 centi-grays of 250 MeV/n Helium (n = 8) and sleep fragmentation at ~6 months of age. During testing, rats were placed in two separate apparati sharing one string (0.2 cm diameter, 162 cm length, 100% cotton) and were required to pull in the string to retrieve Cheerio rewards simultaneously. Twelve trials/day were provided, and behavior was video recorded for offline analyses of cooperative performance, motivation, and sensorimotor function between groups. Irradiated rats took more days to reach criterion (cooperation on 8/12 trials) than sham rats. Criterion percentage was similar between groups once met; yet the amount of pulling between rat pairs during cooperative trials was greater for the sham group. These results suggest that a low dose exposure to Helium negatively impacts cooperation between female rats. If astronauts display similar disruptions after exposure to space flight stressors, then deleterious effects on team dynamics may arise and compromise mission success.https://oasis.library.unlv.edu/durep_posters/1220/thumbnail.jp
Development and Migration: A Case Study of Agricultural Households in Northern Ghana
No full textThis study explores the intricate relationship between economic development and migration patterns in Northern Ghana\u27s agricultural communities. Utilizing data from the EGC-ISSER Ghana Socioeconomic Panel Survey, the analysis focuses on the economic motivations driving migration, considering factors such as urbanization and economic growth. The findings reveal that while urbanization and economic prosperity individually decrease migration, in line with the assumptions of the human capital models of migration, their interaction significantly increases it, suggesting that growing wealthy urban centers; the emergence of new; or the growth of smaller urban centers (made possible due to economic growth) offer enhanced opportunities that attract migrants despite potential saturation. These findings shed light on the complex dynamics between economic development and migration and help make sense of economic development\u27s short-term effects (namely, increased migrations). The results provide a mechanism for understanding the changing levels of migrations (primarily domestic) over the course of economic development. The study offers valuable insights for policymakers seeking to align development strategies with migration management in low-income countries.https://oasis.library.unlv.edu/durep_posters/1244/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
Reproducible Research Data Pipelines – Case Study of Bubble Collapse in Subcooled Nucleate Pool Boiling
No full textVapor bubble collapse is relevant to the study of subcooled nucleate boiling, as can occur in power plants and missile systems, in studies of wear due to cavitation, and even in the study of hydrothermal vents in the Earth sciences. Empirical correlations relate the rate of bubble collapse to thermal conditions of the subcooled fluid, and one may choose to produce a purpose built correlation for any process. However, they are time and resource intensive due to the data and process requirements for automated bubble tracking. A reproducible research data pipeline has been developed to discriminate between existing correlations for a given experimental condition.
The research data pipelines and associated tooling developed throughout the course of this study are open sourced, and the data also published openly. The following codes have been published: BoilerCV, a bubble detection and boiling correlation development pipeline; Boilerdata, a pipeline for producing boiling curves; BoilerDAQ, a library for data acquisition and control of a nucleate pool boiling apparatus; Boilercore, common pipeline utilities; Context Models, a package enabling development of interoperable and reusable data models; and Copier Pipeline, a general project template for research data pipeline development.
The correlation investigation pipeline is promising for correlation selection for a given experimental condition considering the spread in the present correlations, and useful as a general tool for further correlation development and nucleate pool boiling bubble analysis
Addressing Inference Time of Machine Learning Models in Embedded Systems
No full textEmbedded Systems are used for a wide range of specialized computing purposes including surveyal, safety, security, and quality of life. Many areas that embedded systems are used in require the use of machine learning models. Constraints can be placed on embedded systems. Timeliness of execution, user satisfaction, security, power, and resource limitations must be considered when designing for embedded systems. Neural networks excel at complex tasks that are otherwise intractable, but their relatively high computational cost poses a challenge for inclusion in embedded systems. Neural network architectures should be optimized to reduce the total number of operations performed while maintaining comparable accuracy. Fewer operations correspond to faster inference times.
A new neural network architecture, MultiskipNet, is proposed, implemented, and examined. MultiskipNet aims to improve upon existing works for decreasing resource requirements of machine learning models for embedded systems. MultiskipNet is designed to greatly decrease the total FLOPs required to perform image recognition with negligible or no loss to classification accuracy compared to existing models. Relevant existing works are described and used as the foundation for building MultiskipNets. The approach is described and evaluated against baseline models.
The purpose of this dissertation is to examine existing architectures and their relation to embedded systems, propose modifications and new implementations, and evaluate the performance of neural networks and the systems they execute on. Neural networks are chosen as both a mechanism to improve system performance and as an optimization challenge
Removal Capabilities of Zeolite and Zero Valent Iron With High-Level Waste Tank Radionuclides and Metals: Cesium, Strontium and Chromium
No full textHigh level nuclear waste (HLW) has been disposed for temporary storage in underground steel tanks at the Department of Energy Nuclear sites. For example, at the Hanford Site, WA, and Savannah River Site (SRS), SC, HLW account for eighty-eight million gallons (Mgal) and 450 million Curies (MCi) of radioactivity. In the early nuclear activity at Hanford, the waste was discharged to single-shell steel tanks, and the lack of secondary containment allowed leaks, contaminating soil and groundwater. Despite tremendous efforts to stabilize the liquid waste at nuclear sites, treatment is complex, costly, and time-consuming; therefore, HLW may have to be stored in tanks for decades waiting for treatment. Until stabilization is achieved, there is a need to prevent, identify, and/or resolve leaks that occur in the waste tanks.
To address this issue, the project’s purpose is to assess the removal capabilities of BRZTM and ZVI for the removal of Cs, Sr, and Cr (VI). In order to assess the removal capabilities of the BRZTM and ZVI, fixed-bed column tests were conducted. For safety reasons, non-radioactive isotopes were used in the original testing to prevent unnecessary radiation exposure. First, the adsorption performance of Cs and Sr was evaluated when they were used individually with 100% v/v of BRZTM. Column A had an influent concentration of 25 mg/L of Sr, column B had an influent concentration of 25 mg/L of Cs, column C had an influent concentration of 25 mg/L of Cs and 25 mg/L of Sr, and column D had an influent concentration of 25 mg/L of Cs and 2.5 mg/L of Sr. The results showed nearly 100% removal for all columns, which showed that BRZTM was a sufficient adsorbate for the subsequent experiments. The second set of columns was implemented to analyze the removal performance of ZVI for 10 mg/L of Cr when ZVI was used individually. Columns A and B had 10% v/v of ZVI, and columns C and D had 20% v/v of ZVI. The columns containing 20% v/v of ZVI showcased reduced effluent concentrations. The 20% v/v of the ZVI column exhibited approximately 50% removal at 125 bed volume, while 10% v/v of the ZVI column showed roughly half that performance. Next, the behaviors of the Cs, Sr and Cr were examined when mixed together in the influent while BRZTM and ZVI were mixed within the fixed-bed column. All of columns A, B, C, and D contained 20% v/v of ZVI and 80%v/v of BRZTM with an influent concentration of 1 mg/L of Sr and 50 mg/L of Cs while only Cr concentration was varied: 1 mg/L of Cr in columns A and B, and 5 mg/L of Cr in columns C and D. Based on the findings, BRZTM and ZVI are effective materials even when used for a combination of radionuclides and metals. ICP-MS, SEM and EDS analyses were conducted on the used and unused media in order to show the increase in the presence of Cs, Sr and Cr on the surface of the BRZTM and ZVI after usages.
The characterization results and the fixed-bed column experimentation findings will play a crucial role in shaping future research aimed at optimizing the design and implementation of various adsorbents. For example, studies on materials such as activated carbon, zeolites, and metal-organic frameworks (MOFs) could help identify the most effective materials for capturing specific contaminants, such as heavy metals or radioactive isotopes, from waste streams. These insights will not only enhance the efficiency of adsorption processes but also contribute to the development of sustainable solutions that can extend the operational lifespan of waste storage tanks. Moreover, the findings from these studies will support the design of waste management systems that are both resilient and adaptable. For instance, advancements in the development of multi-stage filtration or hybrid adsorption technologies could be incorporated into current waste management infrastructure to improve their capacity to handle variable contamination loads. Such innovations will not only help safeguard the environment but also improve compliance with stringent regulatory standards, ensuring long-term environmental protection while awaiting the establishment of permanent waste storage solutions
Analyzing Fe/Mg-Silicate Chemical Gardens as Analogs to Silicate-Rich Hydrothermal Chimneys on Early Earth and Mars
No full textHydrothermal systems have been proposed as environments for prebiotic chemistry on early Earth. Ancient Mars was an ocean world and could also have had hydrothermal vents supporting biological or prebiotic processes. The Strytan Hydrothermal Field (SHF) in Iceland is a basalt-hosted alkaline vent that forms massive hydrothermal Mg-saponite chimneys and is a potential analog to basalt-hosted alkaline vents that may have existed at the Eridania basin on Mars, where saponite deposits are thought to have formed from ancient hydrothermal activity. Chemical garden experiments have previously been used to simulate aspects of hydrothermal chimney growth for other types of vent systems; however, they have not been much used in this context of a silica-rich hydrothermal system. Here, we studied the formation of Fe/Mg-silicate injection chemical gardens simulating hydrothermal chimneys that represent analogs of precipitates that could have formed in SHF-like hydrothermal vents on the early Earth and/or early Mars. We found that the Fe/Mg ratio of the exterior (ocean simulant) solutions influenced the simulated chimney chemistry under anoxic conditions, and that the precipitates were enriched in Fe compared to the surrounding solution. Simulated chimney compositions as analyzed by Raman, Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy, X-Ray Diffraction, and Visible Near Infrared Reflectance spectra were also affected by whether the chimneys were dried and/or heated post-formation. Our data were suggestive of the presence of Mg-clay like minerals such as saponite or sepiolite in the simulated chimneys, along with amorphous/nanocrystalline Fe phases and Fe-hydroxides, hydrated silica, hematite, halite, and gypsum. Although smectites were not able to be definitively confirmed with ethylene glycol treatment and XRD, this could be due to the precipitates being aged for too short a time to allow for crystallization of an ordered smectite. Though we observed evidence for Mg-silicate and clay-like minerals in the chemical gardens, we did not observe any evidence for Fe-silicate or Fe-containing clay-like minerals; only amorphous silica and Fe hydroxides/oxides, similar to what has been observed in previous studies. This suggests that in SHF-like chimneys on early Earth and/or Mars, Mg would have been present as Mg-hydroxides and Mg-silicates (and, in the presence of additional geological components such as Al, likely phyllosilicates or clays), whereas Fe would be present as Fe or Fe:Mg hydroxides. Such chimneys, containing both reactive Fe-hydroxides as well as Mg-clay-like minerals, would have increased potential for mineral-driven prebiotic chemical reactions
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