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Impacts of Toxic Fescue Seed Consumed by Pregnant Heifers on Maternal Blood Flow and Offspring Growth Parameters: Potential for Melatonin as a Therapeutic to Improve Offspring Growth
No full textThe southeastern United States is home to endophyte-infected (E+), toxic, tall fescue grass. Consumption of E+ fescue by livestock has been linked to fescue toxicosis, a disease reported to cost the United States beef industry around $1 billion in annual losses. The primary objective of this dissertation was to evaluate the influence of pregnant cattle consuming E+ seed during gestation on uterine artery blood flow and growth performance of female offspring. The secondary objective was to investigate melatonin supplementation as a mitigation strategy for expected fescue-associated decreases in uterine artery blood flow and offspring growth performance. The study reported in chapter II investigates the influence of pregnant heifers consuming E+ seed with (M) or without (NM) melatonin supplementation during mid-late gestation on uterine artery hemodynamics, plasma prolactin (PRL) and melatonin (MEL) concentrations, as well as total antioxidant capacity (TAC). Body weight, total uterine artery blood flow (TBF), ipsilateral uterine artery blood flow (BF), ipsilateral uterine artery blood flow as a proportion of body weight (BF/BW), ipsilateral and contralateral uterine artery diameters, and PRL were decreased and ipsilateral uterine artery pulsatility index (PI) was increased in pregnant heifers consuming E+ seed relative to endophyte-free fescue (E-) seed. Concentration of MEL and TAC were increased for M heifers relative to NM heifers. The study reported in chapter III investigates the influence of pregnant heifers consuming E+ seed with M or NM during mid-late gestation on growth performance of female offspring. Gestation length, birth weight, 205-d weaning weight (205-d WW), and post-weaning weights were decreased in calves born to dams that consumed E+ relative to E- seed. Calf birth weight tended to be increased in calves born to M dams relative to NM dams. Calf 205-d WW was decreased in calves born to E+/NM dams relative to E-/NM, E-/M, and E+/M. Ultrasonic estimate of ribeye area (UREA) was decreased in calves born to E+/NM dams relative to E-/NM and E+/M. The study reported in chapter IV investigates the influence of pregnant heifers consuming E+ seed or E- seed during mid-late gestation on feedlot performance and carcass characteristics of female offspring. Dams consuming E+ seed during gestation produced calves with decreased pre-feedlot body weight (BW), UREA, UFAT, ultrasonic estimate of rump fat (URUMP), feedlot BW, hot carcass weight (HCW), back fat (FT), yield grade (YG), and income relative to offspring born to dams consuming E- seed. Percentage of retail product was increased in calves born to dams consuming E+ seed relative to E- seed perhaps due to increased fat trimming. In summary, consumption of E+ seed by pregnant heifers during mid-late gestation resulted in decreased uterine artery blood flow and offspring growth rates. Decreased growth rates were maintained through the feedlot stage and carcasses generated decreased income. Such losses could translate to a decreased return on investment for the producer and packer. However, melatonin supplementation to pregnant dams consuming E+ seed appeared to rescue fescue-associated losses in offspring weaning weight and ribeye area at weaning, indicating potential as a mitigation strategy
An Examination of the Relationship Between Postsecondary Education and Earnings in the Architectural Woodworking Industry
Get PDFThe architectural woodworking industry offers a potential option to job seekers who are looking for alternatives to a formal 4-year postsecondary education. This preregistered quantitative study explores the relationship between postsecondary education and earnings for employees within the architectural woodworking industry. Framed by Human Capital Theory, the research investigates three questions: (1) do postsecondary credentials account for additional variance in income within the industry, (2) is the relationship between postsecondary education and income moderated by whether the credential is related to woodworking, and (3) do individuals with specific types of postsecondary credentials earn higher incomes than those without postsecondary credentials? Data is collected from full-time employees within architectural woodworking companies. The study aims to add to the vast body of empirical evidence on the postsecondary education and earnings relationship, contributing to a gap in the literature on the relationship within the architectural woodworking industry and potentially other specialty trades-based industries. The study will also provide evidence to inform individuals considering the architectural woodworking industry as a career path
Simulations of Richtmyer-Meshkov Instability using high order WENO methods
Get PDFTurbulent mixing due to hydrodynamic instabilities occurs in a broad spectrum of engineering, astrophysical and geophysical applications. Theory, experiment, and numerical simulation help us to understand the dynamics of interface instabilities between two fluids. This thesis presents an increasingly accurate and robust front tracking method for the numerical simulations of shock-induced turbulent mixing known as Richtmyer-Meshkov Instability (RMI). Front tracking is an adaptive computational method, where the interface instability is explicitly represented as lower dimensional manifolds moving through a rectangular grid. All the cell-center states (density, velocity and pressure) are updated using higher order weighted essentially non-oscillatory (WENO) scheme. Performance of fifth- and ninth-order WENO schemes, with and without monotonicity-preserving bounds, as well as the WENOZ method, for the one-dimensional Sod shock tube, shock-entropy wave interaction problem and a scalar advection test problem are presented. Then the Richtmyer--Meshkov instability (RMI) between air and SF6 simulations are performed in order to show the improvements achieved using the new method. The fifth- and ninth-order WENO schemes with and without monotonicity preserving bounds are explored in the numerical solution of the shock-driven interface problem
Evaluating the Impact of Work-Based Learning on Postsecondary Completion and Job Placement of Electronics Technology Students
Get PDFThe manufacturing industry today is facing a critical shortage in the availability of talent and skills needed in an ever-changing technological workforce. With an estimated 2.1 million jobs in the manufacturing industry predicted to be unfilled by 2030, organizations are struggling to find a workforce with the skills needed for this evolving industry (NAM, 2020; Ahmad, 2019). Employers have often suggested there is a lack of alignment between classroom experience in higher education, and work-based learning (WBL) is one option to bridge this gap (Krishnamoorthy & Keating, 2021). WBL provides real world experiences that connect learning in the classroom (Krishnamoorthy & Keating, 2021; Arthur-Mensah, 2017).
The purpose of this research study was to explore the relationship between work-based learning (WBL) participation and postsecondary credential attainment, time to complete postsecondary credentials and job placement in the electronics technology workforce. WBL encompasses multiple types of experiences that provide opportunities to connect classroom instruction with real-world application (Krishnamoorthy & Keating, 2021; Arthur-Mensah, 2017). This study focused on apprenticeships and internships as the types of WBL in an electronics technology field of study.
The research study utilized a quantitative, correlational research approach with a sample population from a regional comprehensive university. Participants were sked to complete a survey. Analysis of the data found that no significant relationship existed between participation in WBL experiences and completion of postsecondary credentials, time to complete postsecondary credentials and job attainment in the electronics technology field. Keywords: Work-based learning, Electronics technology, Credential attainmen
Victims of Stage and Screen: Parasocial Savior Rhetoric and Coded Social Critique at the Convergence of Celebrity & Conspiracy Cultures
Get PDFThis thesis offers a critical rhetorical analysis of what I term parasocial savior conspiracy theories , a unique genre of conspiracy narrative that portrays a public figure as victimized and allows their fans to step into a savior role through their advancement of the conspiracy theory. These narratives, I argue, are both catalyzed by and further insulative to a fan’s parasocial relationship with the public figure in question. Herein, the celebrity acts as a vessel of projection for their fans’ anxieties about control, allowing them to displace their agency panic onto a beloved external party and critique factors that seem to limit their agency, all through a familiar pop culture buffer. As exemplars of this phenomenon, I offer two case studies of distinct parasocial savior conspiracy theories. The first chapter examines “Gaylor” conspiracy theorists as representing an agentic turn in Morris’s (2002) “fourth persona,” receiving private signals from Taylor Swift about her supposed queerness and constructing their advancement of the theory as a moral duty commensurate to the unique knowledge base bestowed upon them. The second chapter focuses on “KateGate” conspiracy theories surrounding Kate Middleton, wherein conspiracy theorists crusade to return her to the public eye as a way of restabilizing the traditional institutions of knowledge and familiar conceptions of white femininity upon which their worldview has come to rely. Ultimately, I argue that parasocial savior conspiracy theories are the product of an increased convergence of conspiracy culture and fandom culture, unique in their narrative construction that allows the individual to assume the role of savior. In turn, this serves to mitigate agency panic, enable what Miller (2002) calls “coded social critique,” and ultimately renegotiates expectations about the general public’s access to knowledge
The Evolving Changes in the Regionalization of Export Bans on U.S. Poultry Trade from the 2015 and 2022 Highly Pathogenic Avian Influenza Events
Get PDFAs food security becomes a growing concern worldwide in a trading system dominated by globalization, the safeguarding of a bio-secure food system is at risk. One of the greatest risks to this stability of the system is, highly pathogenic avian influenza or HPAI which is growing in frequency and impact. Therefore, the global response to disease events is evolving into a newfound understanding of disease prevalence across the animal protein industries. This study will analyze the 2022 HPAI event in the United States regarding the regionalization of restrictions imposed by trading partners accounting for trade agreements executed. The examination of potential shifts in trading partnerships, geopolitical relations, trade agreements, and the adaptation or abandonment of regionalized trade restrictions imposed is discussed. Using publicly available panel data coupled with the gravity model, the shifts in trade relations and the effectiveness of regionalization export restrictions against the United States were explored. The conclusions derived from the model show the need for targeted policies as commodities and regions of the world respond differently to the factors of regionalization of bans
Trouble Don\u27t Last Always
Get PDFBeing born and raised in the South, it has become clear to me that acts of adornment and cultural representations of home are a prevalent factor of the Southern archive. Trouble don’t last always considers the various elements of coloniality that saturate function within the Southern Black home, noting that acts of adornment and cultural representations of home are a prevalent factor of the Southern archive. Enumerating the various roles that Black women play as place makers while also navigating elements of coloniality. In turn these spaces do not function without their knowledge production. This knowledge is one that becomes generational and is inherited through actions of their foremothers. and I am in great debt to mine. I’ll be humming hymns of your love and kindness forever
Influence of Smartphone Notifications on Behavior and Eye Movement Parameters of Emotional Attention
Get PDFThis study examined how smartphone notifications interact with emotional facial expressions to influence behavioral and physiological eye movement parameters of attentional orientation. Using a dot-probe paradigm, participants viewed mixed emotional face pairs (angry, happy, or neutral) following an auditory stimulus (smartphone notifications, control tones, or silence). Angry faces elicited greater behavioral accuracy and delayed initial fixations, consistent with heightened threat-related attentional engagement. Notifications disrupted attentional stability, reflected in increased fixations and pupil size variability. The combined effect of smartphone notifications preceding angry faces intensified attentional modulation—evidenced by slower responses, increased blinking, greater pupil constriction, less pupil variability, and faster initial saccadic orienting. These effects were moderated by individual differences: greater smartphone use—both self-reported and objectively measured—was associated with enhanced sensitivity and avoidance to angry faces, reflected in increased accuracy, larger pupil responses, and reductions in fixations and blinks. Elevated stress and anxiety predicted context-dependent attentional shifts, particularly under threat, with pronounced effects on pupillary and saccadic responses. Lower regulatory control was linked to greater distractibility, impaired performance, and faster threat-oriented saccades, whereas higher attentional control predicted more flexible and adaptive responses. These findings elucidate how smartphone alerts and emotionally salient stimuli interact with trait-level factors to shape attentional processes, highlighting the value of eye-tracking for disentangling cognitive-affective mechanisms in technology-rich environments
Public Comment: Using Critique-like Mediating Artifacts to Democratize Discourse at City Council Meetings
Get PDFAre local governments designed for equitable citizen participation? While civic engagement aims to empower citizens and support representative governance, barriers to participation can hinder those outcomes. City council meetings, key venues for public input, pose specific challenges such as long durations, dense content, and intimidating formalities. These issues disproportionately affect Generation Z (born between 1997 and 2012), who frequently report feeling underinformed or having limited time to engage. This thesis explores how city council meetings might use multimodal mediating artifacts, inspired by design critique practices, to make public discourse more accessible for Gen Z adults.
Grounded in activity theory and Habermas’ public sphere theory, this research frames city council meetings as dynamic systems of discourse, where a citizen’s ability to contribute depends on the tools available to mediate communication. The author introduces multimodal mediating artifacts as unique instruments that utilize more than one mode of communication simultaneously for greater accessibility. To address the communication challenges within city council meetings, the author also turns to another structured form of discourse: the design critique. Contemporary critique practices, in particular, provide intentional, participatory frameworks for exchanging feedback that challenge traditional power dynamics. In this thesis, critique is used as an inspirational model for supporting inclusive, equitable public discourse.
Using Fayetteville, Arkansas’s city council meetings as a case study, this research identifies obstacles to participation through auto-ethnography, interviews, and observational analysis. These methods inform the design of a multimodal intervention encompassing a digital platform with touchscreen interfaces in and around the meeting environment. Drawing from critique structures, these interventions introduce new channels for engagement that are informal, asynchronous, and multimodal. Features are designed with Gen Z in mind, leveraging their comfort with digital communication and screen-based interaction, to build awareness for local issues and reduce knowledge barriers to participation. Ultimately, the work envisions how city council meetings could better support diverse audiences and how multimodal mediation tools can invite and inform civic participation
Mechanical Properties and Microstructural Characteristics of Hydrated BCSA Cement at Extreme Temperatures
Get PDFBelitic Calcium Sulfoaluminate (BCSA) cement is an alternative binder known for its rapid setting and high early strength, making it ideal for applications such as fast-track construction and repair. This study presents a comprehensive investigation into the behavior of BCSA cement under a wide range of curing temperatures, with emphasis on early-age strength development, admixture effects, and the use of the maturity method for strength prediction.
The research evaluates BCSA cement performance in both hot and cold environments, ranging from approximately -28.9 °C (-20°F) to 49 °C (120°F). In warm climates, citric acid was used as a set retarder to improve workability and manage setting time, though careful dosage control was needed to avoid delays in strength gain. In cold climates, combinations of aluminum sulfate and chemical salts such as calcium chloride, calcium nitrate, and sodium chloride, were used to enhance early hydration. These chemical strategies proved effective in mitigating temperature-related performance issues and optimizing the strength of BCSA cement mixtures in challenging environments.
In addition to admixture optimization, the maturity method was applied to BCSA concrete mixtures to estimate in-place strength based on the cumulative effects of time and temperature. Datum temperatures and activation energies were determined experimentally, and maturity equations were developed. The results suggest that, when properly calibrated, the maturity method provides reliable strength predictions at 1 day of age ang later and can serve as a valuable tool in the quality control of BCSA concrete. Extremely early age strengths proved challenging to predict accurately.
Altogether, this investigation highlights the versatility of BCSA cement and provides practical recommendations for its use across a broad range of environmental conditions. By addressing both the chemical and thermal aspects of hydration, this research supports the continued development and implementation of BCSA-based systems in modern construction