UARK (University of Arkansas )
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A New Method Using LiDAR and Well Logs to Identify and Correlate the Pennsylvanian Atoka Formation Subdivisions in the Surface Outcrops of the Boston Mountains, Arkansas
Get PDFThe surface outcrops of the Boston Mountains in northwest Arkansas primarily consist of the Pennsylvanian Atoka formation. Where fully preserved in the Arkoma Basin to the south, the Atoka formation exceeds 18,000 ft of sand and shale. However, it remains undifferentiated on the surface geological map of Arkansas. This study investigates the possibility of identifying and correlating the subsurface subdivisions of the Atoka Formation to the surface outcrops of the Boston Mountains using a new method. Recognizing the Atoka subdivisions in surface outcrops using standard lithology and biostratigraphy correlation techniques has been challenging. The subdivision of the Atoka has instead taken place in the subsurface, as documented by academia and the petroleum industry, utilizing wireline logging tools. These subdivisions are based on reservoir-quality sandstone cycles that can be mapped throughout the basin. This study employs the first derivative of the USGS LiDAR elevation data (LiDAR Slope Map) and subsurface well-log correlations to identify and map the subdivisions, presenting a previously unused surface mapping method for the Atoka Formation. Prior to this, only localized attempts have been made to identify the subsurface Atoka reservoir sandstone units in outcrop. This more detailed geological map of the Atoka Formation in the Boston Mountains will enable geologists to identify the same subunits on the surface that were previously studied solely through wellbore technology. It provides a model for the completion of such mapping across the remainder of the Boston Mountain region
Digitalization of News: Shaping News Consumption Behavior
No full textDigitalization has profoundly transformed news consumption and production, leading to significant societal implications. Notably, the rise of fake news and echo chambers has increased political polarization. On the consumption side, digitalization has altered both the quantity and quality of news consumed, commonly referred to as an individual\u27s news diet. On the supply side, traditional journalistic norms are threatened as news production adapts to digital environments. Essay 1 examines the impact of digital news, conceptualized as a digital object, on news diet quality. This study employs an affordance-based framework to explore the relationship between digital features and individuals\u27 online news consumption. Drawing on affordance theory, information processing models, and the utility of news consumption, we propose a theoretical link between digital news affordances and the quality of individuals\u27 news diets. A mixed-method approach—comprising interviews and an online survey—is used to test our hypotheses and generate deeper insights into promoting a healthier news diet. Essay 2 focuses on individuals’ behaviors in curating news content on social media, particularly those that enhance news diet quality. We investigate the interactive role of algorithmic and social curation mechanisms in shaping news engagement patterns. Additionally, we propose theory-driven design interventions to improve news engagement behavior. We employ a multi-method approach, including online experiments and surveys, to evaluate these interventions to identify effective strategies for fostering desirable news consumption. This dissertation offers novel theoretical insights into the nature of digital news artifacts and their influence on consumption behaviors in the digital era. Our findings provide practical implications for navigating the evolving and complex landscape of digital news consumption and for fostering more informed and responsible engagement with news content
CRISPR-Cas9 Integration of Salmon Elovl2 in Zebrafish Enhances LC-PUFA Biosynthesis and Growth Across Diets
Get PDFFish are a rich source of EPA and DHA, which are well-known long-chain polyunsaturated fatty acids (LC-PUFAs). The sustainable production of these essential fatty acids poses significant challenges, mainly due to our dependence on marine fish and certain nuts. CRISPR-Cas system was utilized to insert the elongation of long-chain fatty acids-like2 (Elovl2) gene from Salmo salar into Danio rerio. Elovl2 was introduced at 10-15-minute post-fertilization, and successful integration confirmed by PCR genotyping, sequencing and expression of EGFP. Approximately 67% of injected embryos successfully exhibited EGFP and sequence results verified the gene integration of Salmo salar Elovl2 at the first start codon. Although Injected embryos exhibited lower hatching rates and higher mortality compared to the wild-type groups, but they successfully expressed the inserted Elovl2 gene, showing approximately a 7-fold increase at the early stages.
GC-MS and RT-qPCR analysis of fatty acid profiles showed that fatty acid biosynthesis-related gene (Elovl2, Fads2, Cpt1a) and adipogenesis-related genes (Fabp4, Pparg, Cebpa) were significantly upregulated in transgenic groups, with significant increases in omega-3 fatty acid levels across various body regions, including the head, trunk and tail at 30-, 60-, and 90-day post fertilization after fed different diets (brine shrimp or commercial diets). Moreover, length (mm), weight (mg) and depth (mm) were increased significantly in transgenic groups compared to the control groups, with further confirming of the RT-qPCR analysis showing the significant upregulation of growth-related genes (Ghr-a, Ghr-b, and Igf1a) and myogenesis-related genes (Myf5, Myf6, Myog, and Myod1) in the trunk and tail regions. Histological analysis also verified the increases of muscle fiber diameter in transgenic groups fed different diets, establishing a strong correlation between gene expressions and muscle hypertrophy. These findings suggest direct evidence of combining genome editing with ideal feeding plans that can significantly enhance aquaculture performance.
Overall, our findings demonstrate that incorporating the Salmo salar Elovl2 gene into zebrafish (freshwater species) enhances omega-3 fatty acid production and improves growth performance. It could be a viable approach to enhance the aquaculture productivity of species with low omega-3 content, providing a sustainable solution for improving fish quality and meeting the growing demand for nutritious aquaculture products
Laughing Tiger
Get PDFLaughing Tiger is the title of my thesis exhibition/paper, as well as the middle name I was gifted with. The relationship I have with this name has changed throughout my life. At one point, this name was more a reminder of being different, but now it is a personal symbol I take pride in. My name is Michael Laughing Tiger Shum, and I make inventive autobiographical paintings about the relationships we invest in, whether it’s with others, objects, rituals, environments, and so on. I have broken down my painting practice into three main themes, which are actions, experiences, and thoughts. Additionally, Intuition, response, and inventing are pivotal to my studio practice. For the viewer, I am considering the experience of paintings in the context of the painted object and analog art experiences. Lastly, I provide my thoughts on relationships/dynamics, the “reality of painting”, and being serious about being silly
\u3ci\u3eIn Vitro\u3c/i\u3e and \u3ci\u3eIn Vivo\u3c/i\u3e Evaluation of the Effect of a Commercial-Dried \u3ci\u3eEnterococcus faecium\u3c/i\u3e Fermentation Product as Quorum Sensing Inhibitors of \u3ci\u3eSalmonella\u3c/i\u3e enterica Typhimurium
Get PDFThe purpose of the present research was to evaluate Enterococcus faecium fermentation peptides (EFP) for antibacterial activity, inhibition of biofilm formation, and anti-quorum sensing properties against Salmonella Typhimurium (ST) in in vitro trials and individual body weight and ST organ colonization in therapeutic and prophylactic models in broiler chickens. Ninety-six day-of-hatch Cobb 500 broiler chickens were randomized and assigned to one of four treatments: NC) Negative Control, no EFP treatment and no ST challenge; NC+EFP) Negative Control, EFP treatment and no ST; PC) Positive Control, no EFP treatment and ST challenge, and PC+EFP) EFP treated and ST challenged. Independent trials for each model were conducted with 12 chickens per cage for a total of 24 chickens per treatment. Samples of the liver, spleen and cecal tonsils were collected in both challenged models to assess the prevalence of ST. In vitro findings indicated no significant differences in ST growth, inhibition of biofilm formation, and autoinducer-1 inhibition with the addition of different concentrations of EFP in the medium. Otherwise, no significant differences in broiler chicken performance and ST prevalence were observed between positive control and EFP-treatment groups in the therapeutic and prophylactic models (P \u3e 0.05). Therefore, EFP does not influence the growth, biofilm inhibition, and anti-quorum sensing properties in ST. Further studies are necessary to elucidate the effects of EFP against other Gram-negatives and Gram-positive bacteria of poultry interest
The Role of Social Media in Shaping Investment Trends Among College Students
Get PDFSocial media has become an increasingly influential force in shaping financial behaviors, particularly among younger generations. This study examines the role of digital platforms in financial education, investment decision-making, and market participation among Gen Z and Millennials. Through a comprehensive analysis of existing literature, case studies, and survey data, this research explores the benefits and risks associated with relying on social media for financial guidance. While social media provides unprecedented access to financial knowledge, empowering young investors with real-time market insights and investment strategies, it also presents challenges such as misinformation, speculative trading behaviors, and the rise of unregulated finfluencers. This research contributes to the growing discourse on the intersection of social media and financial markets, underscoring the need for enhanced financial literacy education, regulatory interventions, and critical engagement with digital financial content
Exploring the Relationship Between Novice Teacher Autonomy and Workplace Engagement, Burnout, and Intentions to Remain in the Teaching Profession
Get PDFAdministrators and experienced faculty frequently disagree on the degree of autonomy that should exist for classroom teachers. Administrators seeking to make adjustments to the levels of autonomy experienced by their teachers may struggle to account for differences between novice teachers and their more seasoned counterparts. This study applies researched-based models for exploring the relationship between various job resources and demands and their ultimate impact on workers. A mixed method designed employing a survey across three large school districts in Arkansas asked participants questions intended to uncover the degree of autonomy novice teachers typically experience, levels of burnout & workplace engagement, and intentions to remain in or exit the teaching profession. Qualitative data intended to identify themes in the experiences of novice teachers related to the aforementioned topics was collected through interviews. The convergence of data indicates that while there may not be a statistically significant relationship between any of the primary variables discussed, there does exist a relationship between the degree of collegiality and trust in a work environment, and novice teacher perceptions and opinions of autonomy
Impact of Various Sealant Materials on Low Temperature Properties of Asphalt Mixtures
Get PDFIn the United States, 43% of the pavement network is in poor condition which can be attributed primarily to different modes of cracking. This network is constantly exposed to the elements and loading leading to thermal and fatigue cracking respectively. Cracking can be addressed through two primary means: mix design and preservation through the application of treatments. However, evaluating these two avenues requires a test that can easily and effectively measure the influence of these factors on thermal and fatigue cracking performance. The two main objectives of this study were to explore the influence of non-standard treatment material (sealant material) on thermal cracking and the development of a dynamic loading fatigue test in the BBR. Little research has been done regarding the effect of sealant material application on the thermal cracking properties (creep stiffness and m-value) of asphalt mixtures in the BBR. In addition, as of 2025 there has been no dynamic loading test developed using the BBR. The experimental matrix included five different mixtures consisting of 3 binder grades (PG 64-22, PG 70-22, and PG 76-22), two NMAS (9.5 and 12.5 mm), and three levels of aging (0, 3, and 5 days). This was followed by five different sealant materials (PJS, FAMF, CTE, CRS-2P, HAAS) applied onto aged base beams. The development of the dynamic loading test was developed using AASHTO T 321 as a basis. PG 76-22 12.5 mm was the best mixture with average creep stiffness and m-value ranging for 4938-6391 MPa and 0.135-0.108 respectively over the 0 day to 5 days of aging. FAMF was the best sealant with an average creep stiffness and m-value of 2611 MPa and 0.114, respectively. The development of the new fatigue test resulted in a functioning software, but the presence of hysteresis couldn’t be addressed so an observed flexural stiffness value was proposed. Both PG 76-22 12.5 mm and PG 64-22 9.5 mm exhibited an increase in stiffness during dynamic loading testing. It was concluded that polymer modification and the application of sealant greatly improved the thermal cracking performance of asphalt mixtures. In addition, in order to further the development of the dynamic loading test the presence of hysteresis must be addressed as well as the variation in loading waveforms because of switching mixture types
Interconnect Selection Tradeoffs at Thermal-Electric Failure Regions in High-Density Electronics
No full textContinued development of high-density electronics has maintained use of solder sphere and wire bond interconnects due to their versatility. Current densities through and temperatures at or close in proximity to these interconnect structures have risen in electronic packages as power density demands have increased over time. In some cases, this trend has forced manufacturers to begin utilizing higher-temperature-capable materials with less well-established reliability estimates or rely on existing packaging strategies (with less redundancy due to continued package size reduction demands) which have not been well-qualified in these elevated stress environments. In this work, laboratory experiments with associated data analysis in concert with analytical modeling have been utilized to better inform material selection in next generation electronic systems and highlight that multiple failure modes can occur in these interconnect structures depending on the magnitudes of the stressors acting on them. Specifically, eutectic gold-tin (80Au20Sn) solder spheres have been examined as a candidate for next generation systems (due to their high melting point compared to conventional solders) through a series of electromigration and combined electromigration and mechanical stress tests. Combined stress testing better represents the use environments of these solder spheres, where ambient temperature and current density are elevated while coefficient of thermal expansion related deformation is simultaneously taking place at soldered regions. To qualify the results from AuSn testing, direct comparisons have been made against eutectic lead-tin (37Pb63Sn) and a common tin-silver-copper (SAC) alloy, SAC305 (96.5Sn3Ag0.5Cu), illustrating that simple selection of solder based on higher melting temperatures may not necessarily be a solution for operating a system at elevated temperatures. A focused examination on the performance of aluminum wire bonds under varied ambient temperature and current density pairs has also been conducted, highlighting that wire bond ampacity is limited by the baseline energy state associated with device and environment temperatures and that the individual contributions of current density and ambient temperature dictate the ultimate failure mode of a given wire bond. Additionally, work has been completed to examine wire bonds under high-density stressors equipped with electrically conductive or insulating coatings in an effort to combat ionic migration resulting from prolonged high power operation, demonstrating that all potential solutions for combating degradation should be subjected to rigorous qualification testing
Designing for Autonomy: Enhancing the Autonomy of Young Women with Postural Orthostatic Tachycardia Syndrome (POTS) through Interactive Narrative
Get PDFPostural Orthostatic Tachycardia Syndrome (POTS) is an autonomic nervous system disorder with multisystem impacts. Classified as a chronic illness and oftentimes triggered by viral infections, incidents of POTS have become increasingly common following the outbreak of COVID-19. Primarily affecting young women ages 18 to 30, POTS disrupts an individual\u27s health during their transition to adulthood. This issue is further complicated by medical gender bias, latent care, and misdiagnosis, which leave this demographic vulnerable within traditional healthcare systems (Shaw et al., 2019). As traditional healthcare systems primarily address acute rather than chronic conditions, interactions with these systems are intermittent. Consequently, individuals with POTS self-manage their condition to achieve or maintain a stable health status (Dubberly et al., 2010). Constant engagement with and movement through the Continuous Cycle of Health Self-Management requires self-determination and, more specifically, autonomy (Ryan et al., 2000). In the context of chronic illness, autonomy refers to the capacity to make choices and retain control over one\u27s daily life despite physical limitations or increased dependence on others (Koester, 2020; Ringstad, 2016). To support young women navigating the constraints imposed by chronic illness and to create opportunities for stable health outcomes, this thesis explores how the design of interactive narratives can foster autonomy for young women with POTS. This research employs a mixed-methods approach that examines autonomy through a Disability Justice lens. Disability Justice is a framework that goes beyond Disability Rights and inclusion, acknowledging the intersectional experiences of individuals with disabilities while striving for collective liberation. This focus shapes the research conducted and the interventions developed, creating a space for collective knowledge and liberation through interactive narratives.
Interactive narrative, as a tool for intervening in the problem space, is derived from Todorov\u27s Theory of Narrative Equilibrium and the dimensions of Interaction Design. Narrative equilibrium functions similarly to the Continuous Cycle of Health Self-Management in that a user starts at one equilibrium (stable health), experiences a disruption (context change, condition change, or regimen change) that leads them to disequilibrium (unstable health). From here, users move through the process of realizing (reconciling), repairing (habituating), and restoring (understanding) to reach a new equilibrium (stable health) (Todorov et al., 1969). In addition to the parallels between narrative and self-management, narrative creates opportunities for autonomy through what author H. Porter Abbot refers to as narrative gaps (Abbot, 2009). Combining narrative gaps with interaction design, this thesis proposes a projection-mapped experience that immerses participants in the cycle of gaining and losing autonomy over their personal narratives. This intervention is complemented by a speculative exhibition that incorporates three additional narratives to restore participants\u27 autonomy. Ultimately, this thesis seeks to contribute to the fields of disability studies, healthcare design, and interaction design scholarship, creating new possibilities for stable health