Electronic Theses and Dissertations

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    Technical Communication in Cybersecurity Awareness and Training a Case Study on the Texas DIR Security Awareness Program
    (2023-08) Ausanka Reese, Joel; Roundtree, Aimee K.; Dayley, Christopher; Williams, Miriam F.
    No abstract prepared.
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    Overbank Soil Erosion Model Validity for Plastic Riverbed Soils
    (2023-08) Alam, Muhammad Tasnim; Kulesza, Stacey; Hwang, Sangchul; Das, Subasish
    Critical shear stress is the hydraulic stress at which soil erosion initiates. An estimate of critical shear stress is needed to predict bridge scour; however, there is no unifying equation for predicting the critical shear stress of plastic soils based on soil properties. Therefore, the current design approach by most State Departments of Transportation is to use an in-house empirical equation, an overly conservative minimum critical shear stress based on an assumed soil property, or by direct measurement. For example, the Kansas Department of Transportation (KDOT) developed an empirical critical shear stress model in 2021 by analyzing 13 soil parameters based on 70 soil samples collected from overbanks. Critical shear stress is a function of the soil's physical, chemical, and biological properties, and these properties are dynamically linked. For this research, ten riverbeds with soils with plasticity were identified and sampled from Kansas. One sample from each site was tested in an erosion function apparatus to determine the critical shear stress. An additional sample was collected and used for measuring the same 13 soil parameters used to develop the previous KDOT model, as well as organic content. When the new data from the ten riverbed samples were combined with the original KDOT model data, the power of the KDOT model was found satisfactory. Furthermore, this study established a new model boundary limit, which improved the power of the overall KDOT model. Therefore, it is recommended that the existing overbank model be used for all riverbed sediments to predict critical shear stress and, ultimately, scour for bridge design in Kansas.
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    Intermolecular Interactions of G-Triplex DNA Assessed by Multi-Channel Surface Plasmon Resonance
    (2023-08) Myhre, Mitchell; Kerwin, Sean; David, Wendi; Lewis, Karen
    G-triplex (G3) nucleic acid structures have recently been proposed as common folding intermediates to G-quadruplex (G4) DNA. Studies on the G3 DNA have been limited, and our understanding of their potential physiological function is in its infancy. To date, several putative G3 forming oligonucleotide based on truncated G4 sequences have been identified. However, the competition between multi-molecular G4 formation and intramolecular G3 formation in truncated G4 sequences has called these putative G3’s into question. This project has aimed toward the development of new methods to identify and study G3 DNA in a manner that precludes G4 multimer formation. Utilizing surface plasmon resonance (SPR), we have identified new putative G3 DNA sequences and qualitatively assessed intermolecular interactions of G3 DNA with several DNA binding proteins.
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    Numerical Simulations of the Evolution of High Mass X-Ray Binaries
    (2023-08) Diehl, Lindsey; Rangelov, Blagoy; Banzatti, Andrea; Togi, Aditya
    High-mass X-ray binaries (HMXBs) consist of a massive star and a compact object such as a neutron star (NS) or black hole (BH). They are important for astrophysics as they provide insights into the life cycles of massive stars and the formation of compact objects. This thesis investigates the evolution of HMXBs, focusing on the influence of initial parameters such as mass, separation, eccentricity, and metallicity. The simulations reveal that the mass distribution and metallicity significantly impact the formation and evolution of HMXBs. We also explore other observable outcomes such as the luminosity of HMXBs and the overall shape of the distribution of the number of binaries at different epochs. These findings provide a deeper understanding of HMXBs and have significant implications for future astrophysical research.
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    The Utility of Cranial and Dental Data in an Integrated Approach to Population Affinity
    (2023-08) Siegert, Courtney C.; Spradley, M. Kate; Herrmann, Nicholas P.; Taylor, Nicole L.; Hefner, Joseph T.; Blue, Sarah A.
    Cranial and dental skeletal data have been used by biological anthropologists to better understand human variation at local, regional, and global scales. While preservation of remains may dictate the availability of data, it is often researcher preference that determines the specific data type is used, typically independent of one another. However, it is unclear to what extent these data types reflect similar population structures. This knowledge gap is significant considering most researchers treat these data types as interchangeable when exploring population relationships and estimating group membership in an applied context. As forensic anthropologists shift from broad estimates of ancestry to the estimation of population affinity and geographic origin, research indicates the combination of multiple skeletally derived data types improves correct classification among closely related groups. Therefore, by assessing the utility of a multifactor and integrated approach to estimating population affinity, the following research sought to treat the skull of modern human populations as an integrated biological unit, while considering the potential impact to forensic methodology. Craniometrics, cranial non-metrics, dental metrics, and dental morphology data were collected from skeletal material representing American Black (n=15), American White (n=140), and Latin American Migrant (n=178) populations. Data were analyzed using latent class analysis, a type of finite mixture modeling used to identify unobserved subgroups or classes within a population. This type of mixture model assumes that within the heterogeneous data, there is a set of unobserved, or latent, variables whose pattern can predict class membership. Results indicate the combination of multiple data types into a unified model consistently identified four and five latent classes or groups within the sample population. This suggests that an integrated approach to understanding human variation has utility in forensic anthropology. By accounting for more within-group variation, this combined approach adds to a growing body of work that indicates skeletally derived data can provide fine-grained group membership estimates (i.e., population affinity), beyond the broad, continental origins associated with ancestry estimation.
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    Examining the Effect of the Pre-Colonization Interval of Insect Scavengers on Human Decomposition Rates in Central Texas
    (2023-08) Young, Lauren M.; Wescott, Daniel; Tomberlin, Jeffery; Hamilton, Michelle
    No abstract prepared.
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    Lead Us Not Into Temptation: Christian Women's Lifestyle Books and the Moralization of Health
    (2023-08) McCleskey, Grace; Pino, Nathan; Giuffre, Patti; Austin, Jasmine T.
    Religious teachings and their connection to health and wellness rhetoric have received limited scholarly attention. This study explores the portrayal of the relationship between health and religion in contemporary Christian women's lifestyle books. The study employs a qualitative content analysis of fifteen popular books published within the last five years, aiming to identify patterns in their descriptions of health, accessibility of advice, treatment of weight and beauty standards, and the presence of direct or indirect connections between health and sin. Self-help rhetoric and religious discourses often depoliticize women's concerns and reinforce patriarchal structures, and these books have proven to be no different. Five major themes emerged upon conducting this qualitative analysis: connections to Eve and original sin, the importance of individual responsibility, creation in God’s image, authenticity and relatability, and the fight between good and evil. While some of the authors made attempts to present women’s bodies in a more positive light, nearly all of them portrayed weight gain as a moral failure, while rejecting the idea that maintaining thinness is a vain or aesthetic decision. By bridging the gap in existing literature, this study aims to shed light on the often-overlooked interaction between Christian rhetoric and the portrayal of health and morality in contemporary women's lifestyle books. These findings contribute to a better understanding of the implications and challenges posed by today’s pervasive wellness culture, allowing for a more nuanced analysis of the connections between religion, women's experiences, and their beliefs about how their own bodies and the bodies of others should be maintained and presented.
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    The Nature of X-Ray Sources in the Andromeda Galaxy
    (2023-08) Nava, Erika Marentes; Rangelov, Blagoy; Togi, Aditya; Banzatti, Andrea
    Using the Panchromatic Hubble Andromeda Treasury (PHAT) Program and Chandra X-Ray Observatory, we have acquired archival data from ~1/3 of Andromeda Galaxy to study the properties of the X-ray sources. Only a small fraction (~1/3) of the X-ray sources within Andromeda have been classified. We determined a total of 799 x-ray sources with 781 of them containing more than one counterpart. We present preliminary analysis of the archival data including color-magnitude diagrams, x-ray spectral analysis, and theoretical modeling that help us determine what these sources are.
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    Distribution and Occurrence of Stygobionts in Hyporheic Systems Downstream of Karst Regions
    (2023-08) Sparks, Kenneth; Schwartz, Benjamin F.; Hutchins, Benjamin; Altman, Safra
    The hyporheic zone is the ecotone between surface water and groundwater in which diverse and complex biological and geochemical processes occur (Krause et al., 2011). This ecotone and the interactions that occur in it provide aquatic organisms with nutrients and habitat. Epigean taxa, and stygobionts that dwell in groundwater systems, may coexist, and interact in the hyporheic zone. Although the Edwards Aquifer is the most biodiverse and well-studied groundwater habitat known in Texas, the distribution and abundance of stygobiont and hyporheic-obligate taxa in hyporheic zones outside of the Edwards Aquifer and Edwards Plateau, are not well characterized (Hutchins et al., 2018 & 2020). Recent discoveries of stygobionts at sites distal to mapped karst regions suggests that there may be extensive non-karstic habitat for these taxa, including in alluvial systems downstream from the karst (Hutchins et al., 2020). Hutchins et al. (2020) showed that stygobiont species richness is positively correlated with the presence of karst, which suggests that karst aquifers may be source populations for emigration from the karst into adjacent non-karst regions. This also implies that the distance from karst may be related to stygobiont presence, abundance, and diversity. The goal of this research was to 1) assess the potential for off-karst alluvial systems to serve as habitat for ‘karst-adapted’ species, and 2) if stygobionts are found in non-karst alluvial sites, to determine how their diversity and abundance are related to distance from karst. I studied the abundance and diversity of stygobionts at 11 non-karst alluvial sites in the San Marcos River between 3 and 140 river km downstream from the Edwards Aquifer. I collected 55 hyporheic invertebrate samples and sorted, counted, and identified them at the lowest feasible taxonomic level. Environmental parameters (temperature, dissolved oxygen (DO), pH, specific conductivity (SC)) and hydraulic conductivity (K) were measured at each sample location. Linear mixed effects models were used to investigate relationships between response variables (abundance and biodiversity) and predictor variables: K, (DO), percent alluvium in 2-km buffer surrounding the site, and distance downstream from karst. Abundance and diversity of stygobiontic invertebrate counts per sample were significantly affected by K, DO, and distance from karst. Percent alluvium and underlying geological formations did not predict either abundance or diversity. Stygobiont abundance was exceptionally high in some samples; higher than in any other hyporheic sample collected in Texas. I also expanded the known ranges of several uncommon stygobionts and provided important information about the range of habitat conditions that these and other species may occupy. This was the first study in Texas to systematically investigate the extent to which stygobionts utilize alluvium downstream from karst as habitat and shows that these habitats have unrecognized importance for species previously assumed to primarily inhabit karst systems. Alluvial habitats downstream from karst systems should be further evaluated for presence and abundance of stygobionts. This is especially true for species that are of conservation concern, as these findings may have implications for management and conservation actions.
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    Voices of Change: Three Case Studies Connecting Black Music Through Pop, Hip Hop, and Jazz
    (2023-08) Washington, Christopher; Mooney, Kevin E.; Pedroza, Ludim; Schüler, Nico
    This thesis contrasts African American music of different genres - pop, hip hop, and jazz - centering on three prominent artists of the late 20th and early 21st centuries: Beyoncé, Kendrick Lamar, and Wynton Marsalis. While there have been studies that have focused individually on the political expressions in pop, hip hop, and jazz, this thesis focuses on the interconnections between and among these three genres. For example, on pop music as a political expression, see Christina Baade and Kristin McGhee and their collection of essays in Beyoncé in the World: Making Meaning with Queen Bey in Troubled Times (2021). Bonnette’s Pulse of the People: Political Rap Music and Black Politics addresses the origins of political rap in addition to examining several examples from rap’s inception with particular attention toward these performers’ attitudes expressed through their music. Regarding jazz as a political expression, see Ed Sarath, Black Music Matters: Jazz and the Transformation of Music Studies (2018) and Richard Brent Turner’s book Jazz Religion, the Second Line, and Black New Orleans, After Hurricane Katrina New Edition (2017). My thesis, centering on the interconnections between pop, hip hop, and jazz, specifically among Beyoncé, Lamar, and Marsalis, draws on the work of Guthrie P. Ramsey, Jr., the writers in the collected essays of Fernando Orejuala and Stephanie Shonekan, and James Gordan Williams. Ramsey’s book Race Music: Black Culture from Bebop to Hip Hop (2003) interrogates the discourse on the interpretation and appraisal of the history of black music from a chronological perspective, centering on the poetics of “race music.” It is of interest to me because of his discussion of artists such as Stevie Wonder who “crossed over” into political songs to express cultural nationalism through his Songs in the Key of Life (1976). This book furthermore aids in connecting trends of my case studies from the 21st century with the historical significance of similar rifts in black musical expression from the 1990s black cultural explosion. The collected essays of Orejuela and Shonekan titled Black Lives Matter and Music: Protest, Intervention, Reflection (2018) stemmed from the session of conference presentations at the 2015 annual meeting of the Society of Ethnomusicology entitled “Black Music Matters: Taking Stock.” The focus of this session was to evaluate the perils and complications of black music while offering a lens into black culture. I am using this book on the strength of where it begins by culminating black student life at the University of Missouri one year after the killing of Michael Brown in Ferguson, Missouri, August 9, 2014, amid Black Lives Matter. Williams, in his book Crossing Bar Lines: The Politics and Practices of Black Musical Space (2021), also written during a specific historical time marked by vigilante murders of Blacks, identifies three generations of black musicians for his case studies on what he calls “Black musical space,” encompassing such dualities as joy/sorrow, hope/despair, and life/death. Williams seeks to understand how five musicians use their improvisation as a manifesto to culturally respond to issues of social inequalities which are in line with my efforts to connect why black artist today are taking performance platforms to respond similarly. My thesis highlights three case studies of notable performances by Beyoncé, her 2016 performance at the Super Bowl that addressed black identity, female empowerment, and police injustice, with a strong connection to Black Lives Matter, Kendrick Lamar’s 2016 performance at the Grammy Music Awards that included a medley, referencing racial inequality, the prison system, and black congruence; and, in 2020, Wynton Marsalis’s performance of “Amazing Grace” after his invited speech on what democracy and jazz have in common, kicking off the series, “Reflections on Democracy” at the Federal Hall Grand Rotunda, New York. Each of these case studies focuses on Grammy winners who had selected such high-profile performance contexts as the Super Bowl, Grammy Awards, and the 2020 national election respectively, and each of their performances echoes issues of the times in their respective ways: the killing of unarmed Black men and women, racial profiling, and voting rights. Not only do I demonstrate similarities between each of the case studies’ musical performances, how each relates to the prevalent issues of the Black communities, more specifically Black Lives Matter, and how each is significant in the music of the 21st century, I also investigate the extent to which these artists have influenced others who have become a beacon of change through their music. My case studies include lyric and music analyses, considerations of performance contexts, and supporting my interpretation with relevant secondary literature referenced above among others. Even though there have been studies on race, music, and politics, this thesis identifies specific musical expressions of advocacy that arguably provide a conversational bridge between pop, hip hop, and jazz in the 21st century.
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    Connecting Interest in and Awareness of the Environment with an Informal Experience
    (2023-08) Wait, Miranda Louise; Daniel, Kristy L.; Williamson, Paula S.; Forsythe, Michelle S.
    Universities play an important part in creating a more environmental literate society and providing resources to help encourage more people to enter STEM careers, a rapidly growing field in a time where environmental issues are becoming more of a worldwide concern. The responsibility for solving these issues is being left to the younger generations (Wang & Zhang, 2021), and universities need to take a more active role in environmental decisions and practices by regarding their students as our future community leaders, decision makers, and opinion shapers as the future of our society (Gurbuz & Ozkan, 2019). For this study, I aimed to look at how an informal learning experience, as part of a mandatory class at a university, affected students’ interest in and awareness of science, STEM careers, and environmental issues. I used the theoretical framework of “science capital,” a conceptual theory on how to use the experiences that a person is provided in supporting and enhancing people’s attitude, engagement, and participation in science (Archer et al., 2022). I created a pre- and post- questionnaire by combining four instruments: STEM Semantics Survey, Environmental Awareness Questionnaire, Relevance of Science Education-D, and STEM Career Interest Questionnaire. The participants in this study were university freshman students enrolled in a mandatory class designed for freshman, which also included a glass-bottom boat ride as an informal learning experience, part of a nature and research center part of the university campus. I expected that the students who participated in the study would have an increase in their interest in and awareness of STEM, science, environmental awareness, and STEM careers. My assumption was that there would be an increase, whether it was minimal or significant, in either of the areas. Results from the study were mostly insignificant for the impacts of glass-bottom boat ride on the opinions of the students. The p-values found were statistically insignificant for all scales in each instrument except for the STEM Semantics Survey scale for math and the Environmental Awareness Questionnaire scale for “interest in nature”, inferring that the treatment of the boat ride did not have a statistically significant effect on the students’ STEM, environment, and science perceptions. However, the implications of the study with other research shows that with an increase of similar opportunities, there is a potential to make an impact in student’s interest in and awareness of STEM, the environment, and opportunities within STEM career fields.
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    A Robust and Power Efficient Software Encryption Method for IOT Framework Communication Using Zigbee Protocol via XBees
    (2023-08) Obisakin, Inioluwa; Aslan, Semih; Droopad, Ravi; Valles, Damian
    In this study, our focus is on Zigbee, a wireless communication standard that uses IEEE 802.15.4, a prevalent short-range wireless communication standard, for both indoor and outdoor applications. The effectiveness of Zigbee relies on various networking parameters, including transmission distances, deployment environment, hopping, baud rates, and transmission power. Zigbee security and data encryption is based on security defined in the 802.15.4 protocol. The encryption algorithm used in Zigbee is a network-level symmetric AES (Advanced Encryption Standard) with a 128-bit key length. However, newer versions of AES (196 & 256-bit) are more substantial, and asymmetric encryption methods are better suited for systems with a sender and receiver. As such, this study aims to determine a robust application-level encryption method for the Zigbee protocol by examining standard IoT transmission parameters, such as Received Signal Strength, latency, and packet delivery ratio, as well as its power efficiency by examining power consumption during various stages of the Zigbee transmit and receive cycle at different transmit power levels. To achieve this goal, we have implemented AES-256-bit(symmetric) and Public Key Cryptography (asymmetric) encryption methods and compared their performance to the existing AES 128-bit encryption method. Our findings reveal that AES-256-bit encryption leads to higher power consumption, which can be mitigated by adjusting the transmit power levels. On the other hand, PKC encryption provides a better solution in terms of power efficiency, although it is slower in terms of encryption speed and higher latency. This study's contribution lies in its attempt to understand the performance tradeoffs involved in the security of Zigbee networks by proposing application-level encryption methods and benchmarking it against the default encryption. The findings of this study can assist developers and researchers in making more informed decisions when selecting encryption methods for Zigbee networks.
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    A Comparative Study on the Effects of Arbuscular Mycorrhizal Fungi on Trapsacum Dactyloides, Zea Diploperennis and Zea Mays
    (2023-08) Besse, Kailyse; Mix, Ken; Mondal, Sejuti; Fulton, Lawrence
    No abstract prepared.
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    Modeling and Optimization of Security Screening Resources in Airport Terminal Checkpoints
    (2023-08) Subramanian, Palaniappan; Perez, Eduardo; Ramirez, Clara M. Novoa; Méndez Mediavilla, Francis A.
    Allocating security screening resources in airport terminal checkpoints is a critical task that directly affects airport operations’ efficiency and effectiveness. Passengers may experience long wait times and inefficient use of resources due to the traditional manual allocation approach. Due to the complex and dynamic nature of passenger flows and security risks, traditional allocation methods may not be optimal. In this thesis, a simulation-based optimization approach for improving the allocation of security screening resources in airport terminal checkpoints is developed. The goal of the methodology is to minimize passenger waiting time and guarantee a satisfactory level of safety screenings. Simulation-based optimization can be a valuable tool for airport operators to optimize resource allocation and make informed decisions in checkpoint operations, as suggested by the results. The research is divided into two main chapters, with the first chapter focusing on the development of the simulation model and the second chapter focusing on optimization techniques. In the simulation chapter, we develop a comprehensive model of the airport terminal checkpoint system using discrete event simulation. This model captures the flow of passengers, security screening processes, and analyzes resource utilization within the checkpoint environment. By simulating various scenarios and adjusting key parameters, we evaluate the performance of the current resource allocation strategy and identify areas for improvement. Building upon the insights gained from the simulation chapter, the optimization chapter aims to enhance the allocation of security screening resources by employing advanced optimization techniques. We formulate the resource allocation problem as an optimization model and leverage mathematical programming approaches to find optimal or near-optimal solutions. The objective is to minimize passenger waiting times, reduce resource idle time, and maximize overall system efficiency. By combining simulation and optimization, our approach provides a comprehensive framework for improving security screening resource allocation in airport terminal checkpoints. The findings of this research have the potential to enhance security measures while simultaneously improving passenger experience and operational efficiency. Furthermore, the proposed approach can serve as a valuable decision support tool for airport authorities and security agencies in their efforts to optimize resource allocation in dynamic and complex checkpoint environments.
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    A Data-Driven Framework for Planning the Expansion of the Trauma Healthcare Network in Texas
    (2023-08) Saha, Sabhasachi; Perez, Eduardo; Méndez Mediavilla, Francis A.; Valles Molina, Damian
    Trauma care services are a vital part of all healthcare-based networks as timely accessibility is important for citizens. Trauma care access is even more relevant when unexpected events overload the capacity of the hospitals. Research literature has highlighted that access to trauma care is not even for all populations, especially when comparing rural and urban groups. Historically, the configuration of a trauma system was often not considered but instead hinged on the designation and verification of individual hospitals as trauma care centers. Recognition of the benefits of an inclusive trauma system has precipitated a more holistic approach. The optimal geographic configuration of trauma care centers is key to maximizing accessibility while promoting the efficient use of resources. This research proposes the development of a two-stage stochastic optimization model for geospatial expansion of a trauma network in the state of Texas. The stochastic optimization model recommends the siting of new trauma care centers according to the geographic distribution of the injured population. Data analytics are used to represent the demand for services in different regions. The model has the potential to benefit both patients and institutions, by facilitating prompt access and promoting the efficient use of resources.
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    Parent Perspective of Autistic Students on Factors of Denial from Special Education in Texas: A Multiple Case Study
    (2023-08) Ota, Michael; Martinez, Melissa A.; DeMatthews, David; Guajardo, Miguel; Price, Larry
    In 2005, the Texas Education Agency implemented a new accountability measure for school districts that penalized those that had more than 8.5% special education enrollment. The policy that lasted for over a decade and its implications, which continue to this day, created inequitable access to services for students with disabilities of all socioeconomic and racial/ethnic backgrounds as school leaders struggled to keep percentages down. Researchers and advocates provided ample evidence that Texas was artificially suppressing special education enrollment using narratives and statistical analysis by arguing that the state had an 8.7% enrollment compared to a national average of 14%. The evidence got the attention of the U.S. Department of Education, which issued a report in 2018 confirming the agency’s multiple violations and including corrective actions. Most compelling was that the policy resulted in some estimates to be around 25,000 students with disabilities not receiving a free appropriate public education. One of the fastest growing segments of special education is autism; yet, as many as 36% of those with an eligible autism disability are not receiving services, which may have been exacerbated by the special education cap policy. Current research is clear on why this happens: poor evaluator training; inappropriate assessment tools; and insufficient funding. However, many of these barriers to services could be resolved by implementing the inclusion mandate, which includes community resource involvement and collaboration in the eligibility process. The purpose of this study was to examine how the Texas special education cap policy affected families with autism, in particular the student with a medical diagnosis of autism enrolled in a public school, in receiving services and their perspectives of school administration as agents of oppression, which may be continuing today. Themes were analyzed against a community model framework based on critical disability theory, including collateral costs of eligibility denial, lack of quality evaluators and training as a major factor, and a pervasive “culture of denial” that appears to exist today. Recommendations were provided so that school administrators and district leaders can take immediate corrective action. In doing so, I hope to change the systemic factors that created and continue to propagate inequities for families with autism.
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    Black Soldier Fly Larvae (BSFL) and Frass as Protein Supplements for Beef Steers Consuming Low-Quality Forage
    (2023-08) Maggitt, Shakara; Drewery, Merritt; Wickersham, Tryon A.; McCann, Joshua
    Increased global meat consumption has led to an increase in livestock production. While the demand for output increases, so has the need for alternative protein sources in feed to minimize the environmental impact of livestock production. Insect protein is a potential alternative to conventional sources of protein (e.g., soybean meal or cottonseed meal) for cattle consuming low-quality forage (LQF). The use of insects as livestock feed has been documented in the literature, and interest is growing; however, the Association of American Feed Control Officials (AAFCO) has only approved the use of dried black soldier fly larvae (BSFL) for salmonid, poultry, swine, and adult dogs. The objective of this experiment was to evaluate the use of Black Soldier Fly Larvae meal (BSFLM) and BSFL frass and larval sheddings (FRS) as novel supplemental proteins for beef steers consuming low-quality forage. Eight ruminally fistulated steers (240.2 ± 22.5 kg of BW) were used in replicated 4 × 4 Latin squares. One of four treatments were provided to each steer per period: a control (CON) with no supplement, cottonseed meal (CSM), partially defatted BSFL meal (BSFLM), or BSFL frass and larval sheddings (FRS). Four 16-day periods were conducted with an 8-d adaptation to treatments, 7-d measurement of intake and digestion, and 1-d collection of ruminal fermentation and microbial samples. Dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) were determined for forage, supplement, ort, and fecal samples. Microbiome analysis of microbial communities’ composition was conducted using 16S rRNA sequencing for liquid and solid rumen fractions. Protein supplementation of CSM, BSFLM, and FRS increased forage organic matter (OM) intake (P < 0.01) relative to CON with no significant differences between CSM and FRS (P=0.84) or BSFLM and FRS (P=0.13) and with a trend for a difference between CSM and BSFLM (P=0.08). Provision of BSFLM and FRS increased total digestible OM intake (TDOMI) relative to CON (P < 0.01), from 2.33 kg/d for CON to 3.07 kg/d for BSFLM and 3.05 kg/d for FRS. The dominant microbial phyla in the liquid fraction were Firmicutes (44.3%) and Bacteroidetes (40.7%) and, in the solid fraction, were Firmicutes (70.4%) and Bacteroidetes (20%) with no significant differences for phyla across treatment within either fraction. There were treatment effects within the liquid and solid fractions for certain genera. Overall, our results indicate that BSFLM and FRS can be incorporated as a protein source for beef steers consuming low-quality forage.
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    An Analysis of Online Wildlife Trade: A Situational Crime Prevention Approach
    (2023-08) Rogers, Tiffany Gentry; Summers, Lucia; Jones, Shayne; Pires, Stephen; Roche, Sean Patrick
    The illegal trade of wildlife and wildlife products is valued in the billions of U.S. dollars each year. This trade affects biodiversity, local economies, political corruption, and places wildlife law enforcement in harm’s way. Generally, the detection rates of wildlife trade are assumed to be low. Issues of categorization and enforcement inhibit detection efforts. The Internet contributes to low detection rates by removing a human point in the sale chain, as it connects collectors with buyers directly. Online wildlife trade is not well represented in U.S.-based research. This dissertation contributes to the existing evidence base by providing information regarding trade into the United States using both official seizure data and online advertisement data, and by suggesting means by which preventive intervention may be implemented. Seizure data from 2000-2018 provided by the United States Fish and Wildlife Service was used to identify products encountered most often— “hot products.” These hot products were systematically searched in Google, Bing, DuckDuckGo, Etsy, and eBay, with advertisements indexed. An exhaustive descriptive analysis was performed on both the official seizure data and the online advertisements. The online ads were also subjected to a script analysis (Cornish, 1994) of the shipping techniques used by online wildlife traders to deconstruct the process and aid in developing points for potential intervention. The findings from this study present a novel understanding of how the open and deep webs are used to trade wildlife. This study serves as a foundation for further research examining successful points for intervention.
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    Characterization of polymer modified asphalt binders containing processed oil
    (2023-08) Hemmati, Navid; Lee, Soon Jae; Beverly, Harlan; Kim, Yoo Jae; You, Beyoung Hee; Yeon, Jung
    The current study investigates the impact of processed oil on asphalt binder PG 64-22 and conjugate of it with common modifiers such as Crumbed Rubber Modifier (CRM), Styrene-Isoprene-Styrene (SIS), Styrene-Butadiene-Styrene (SBS) and Petroleum Resin (PE). The binder was tested at different temperatures, and different amounts of modifiers and processed oil were added to the binder. The modified binders were also aged artificially using different procedures. The study found that adding processed oil to polymer modified binders reduces viscosity and improves workability, while the modifiers improve the rutting resistance of them, however, the addition of processed oil reduces the binder’s rutting performance due to decrement of viscosity. The study also found that the conjugating of modifying polymers and processed oil improves the low temperature cracking resistance. The study’s results indicate that co-modifying polymer binders with processed oil resulted in a significant reduction in viscosity values, resulting in improved workability. The results also showed that increasing the processed oil concentration from 6% to 12% caused a viscosity reduction in conjugation of CRM, SIS, SBS and PE. Even though the addition of processed oil results in a reduction in the rutting performance of asphalt binder, the addition of polymers significantly improved the rutting resistance of asphalt binders. The modified asphalt binders containing 6% and 12% processed oil decreased the G*sin δ values. This reduction caused improvement of fatigue cracking resistance of all binders modified with CRM, SIS, SBS and PE. The higher concentration of processed oil means 12% showed greater reduction rate compared to the asphalt binders containing 6% processed oil. The BBR results for modified asphalt binders showed that the incorporation of CRM, SIS, SBS and PE and processed oil improved the low temperature cracking resistance significantly, due to the high penetration rate of processed oil in asphalt binders during modification.
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    Investigating the Effectiveness of Mindfulness on Coastal Recreationists to Mitigate Waterbird Disturbance
    (2023-08) Laycock, Brooke Ann; Serenari, Christopher; Green, Clay; Daniel, Kristy
    Growing coastal recreation across the globe is leading to more intense disturbances to wildlife. In particular, waterbirds such as Black Skimmers (Rynchops niger) on rookery islands, are experiencing severe population declines. A population decline for this species can have cascading consequences across the coastal ecosystem, this surging effect is due to the black skimmer's role as a bioindicator species. Species deemed as bioindicators are notorious for keeping environments at bay for disease outbreak and over population of other species within the ecosystem. Thus far, research on the mitigation of recreational disturbance to coastal bird species has focused on the efficacity of increasing enforcement mechanisms such as signage along the coast. While this approach may be effective in some contexts it is ineffectual in secluded environments that lack rules and regulations, law enforcement patrols, or spectators. The purpose of this study explored the efficiency of contemplative pedagogy focusing on enhancing attention, reflection, and heightened awareness. Specifically, this study focused on mindfulness as a useful tool to help recreationists manage their own behavior. Findings from interviews with 21 recreationists and biologists revealed that recreationists who were more thoughtful about their intentions, attention, and attitudes towards waterbird populations emerged more likely to conserve waterbirds. Additionally, informants were able to identify the user group that contributes the most impact to the waterbird population with 18 out of 21 identifications pointing to anglers. The data from this study also suggests that in order to reduce recreational disturbance to waterbirds and increase enforcement compliance, coastal managers should look to designing education and outreach programming that targets mindfulness. An exploration on the effectiveness of recreational compliance with waterbird conservation efforts in coastal areas, specifically on rookery islands on the Texas coast also took place in this study. The final analysis revealed that recreationists have different levels of compliance with conservation mechanisms, ranging from recognizing and complying, willing non-compliance, to unknowingly non-compliance. I furthermore explored the concepts of Nudging and Shoving to assess how to convert recreationists who do not comply to be compliant. I found that low-touch nudge mechanisms, such as signs, handouts, and emails, have minimal results in conservation efforts. Incorporating acts of shoving in the form of low-touch shove and high-touch shove could increase compliance and promote coastal waterbird populations to flourish. This study highlights the important correlation of recreational awareness and compliance with waterbird conservation efforts in coastal areas. The data suggests that mindfulness and both nudging and shoving can be an effective way to promote compliance while mitigating the negative impacts of recreational activities on coastal waterbirds.