Doctoral Dissertations

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Intersection and inflection points: Exploring the lived experience of advanced placement calculus students using narrative inquiry
(2024-11-13) Peterson, Ryan
This dissertation uses narrative inquiry, a qualitative methodology, to explore the lived experience of two Advanced Placement Calculus BC students. The research questions are as follows: What are the lived experiences of advanced placement calculus students? What do those experiences tell us about secondary mathematics education in the 21st century? What relationship do students experience between their coursework and their daily lives? In this study, the participants are in the process of navigating the challenges of a high-level mathematics course while in the final year of their secondary education. The personal narratives of the participants and their teacher are communicated through the use of interview excerpts, journal entries, correspondence, and classroom artifacts. These stories intersect with broader educational, social, and institutional frameworks, including high-stakes testing, the role of family in education, and the U.S. education system’s “senior year” phenomenon. While Advanced Placement coursework provides an intersection point for the participants and their teacher, the study also explores the role of mentorship, support services, and the importance of prior knowledge. The findings offer insight into how narrative inquiry can play a role in understanding student learning in rigorous science, technology, engineering, and mathematics courses. Additionally, the study contributes to broader discussions of pedagogy, curriculum design, and Advanced Placement programs.
Andean cosmology and charging the universe: Colonial concepts of power, healing, and transformation in the Andes
(2023-08-03) Albers, Jeremy Michael
This dissertation focuses on Andean cosmology and colonial concepts of healing in the Andes in the sixteenth and seventeenth centuries. This dissertation provides evidence that redefines aspects and understandings of Andean cosmology that pertain to health and well-being and the causes for illness. In the Andes, Native healers accessed the basis of power for healing that resided in a life-giving and life-animating essence called camac that continually renews and recharges the cosmos. Camac flows through focal areas or objects called huacas, which early colonial Andeans revered and honored. Andean notions of reciprocity (ayni) and shared resources (sapsi) required Natives to engage the living world to maintain the flow of energy for health and vitality. Andean healers utilized camac of spaces, huacas, plants, animals, minerals, and objects of power in their rites and rituals to affect change in people, livestock and crops, land, and relationships. This purpose of this dissertation is to offer an alternative framework for Andean cosmology that centers on the flow of camac as the central concept for power in the Andes, whereby huacas serve as focal points of vitalizing energies. Huacas, like the sun and moon, are focal points of power that adhere to the cosmological order that were accessible to Andean healing specialists. Utilizing church documents, government documents, colonial reports and histories, early Quechua-Spanish dictionaries, and cultural remnants, I mitigate religious and ethnic biases by scrutinizing key terminology and phrases against attitudes, actions, and misunderstandings of early encounters between Andean ethnic groups and European colonizing agents. Redefining Andean cosmology in the early colonial period alters the Spanish-Catholic narrative of Native healers and their beliefs that currently permeate into the 21st century.
"A pioneer editress": Frieda Cassin's complex contributions to the 19th century Caribbean Creole literary world
(2023-04-28) Farrier, Abigayle Anne
This project is a large-scale recovery of Frieda Cassin’s (1870-1915) life and work. Cassin is the earliest Antiguan novelist, founder of the first Antiguan literary periodical, and one of the earliest female literary periodical editors in the Caribbean. This project includes both literary analysis of her work and historical recovery of her life and periodical, as well as a scholarly edition of all six issues of her periodical, none of which have been published in this century or recovered. In this project, I argue for the importance of recovering Cassin’s life and work; as an author, editor, and Antiguan citizen, she offered a critical intervention in the Caribbean literature marketplace of her day and was successful by numerous measures, including international recognition in both the Americas and England. I examine the importance of the transatlantic connections between Antigua, the United States, and England, and through doing so, demonstrate how Cassin responded to cultural forces at play in the nineteenth century – participating in some (e.g., racist language and its ideological underpinnings) while resisting others (e.g., gender and racial hierarchies). It is my hope that this project will provide an adaptable model for dealing with the authorial history of a figure whose work and life contain both problematic and admirable features, especially in a place like the Caribbean, with its hybrid culture and complex social hierarchies.
Wrecked: Women's bodies as imperial ruin
(2023-04-24) McDaniel, Susannah Sanford
This dissertation uses the lens of ruin and ruination to interrogate the workings of empire, broadly defined. Ruination, the ongoing creation of ruin, continues across historical time and exists in physical and remembered forms, as well as textually constructed memorials like novels and life writing. This dissertation argues women are ruin and detritus of empire while constituting imperialism as constructive actors. They both perpetuate empire and become the wreckage, reflecting imperialism back onto itself. This dissertation searches for and examines the moments where ruination is experienced or prevented, where regulatory standards regarding women’s bodies are troubled, or where violence is imposed. Chapter One argues that sexual transgression in early eighteenth-century novels requires explicit association between women characters and the colonial economy. The second chapter moves from London and prose fiction to the southeastern coast of India and life writing, arguing that ruin and ruination in fact define imperialism in India in the mid-eighteenth century. The work of imperialism occurs in small, personal interactions, holding up its more visible edifices of occupation and exploitation. The third chapter places two different accounts of the Haitian Revolution next to one another, juxtaposing narrative form, the causes of revolutions, and the effects. Chapter Three argues Black ecofeminism, the tying of liberation of bodies to liberation of nature, counters white imperialism. The epilogue looks forward to nineteenth-century iterations of the “ruined” woman, finding inescapable reminders of the violence of settler colonialism and violent reactions to disability. This dissertation extends and complicates historical arguments regarding the ruins of imperialism to argue people are also left with the debris of bodies—physical, narrative, metaphorical. Ruin and ruination can be and have been written on both actual and literary bodies.
Storytelling and user experience design: How stories shape design and how design shapes everythying
(2024-08-07) Robins, Colin
Increasingly, classic storytelling techniques are being used in the technological space to communicate ideas or ideals that would be otherwise hard to communicate. Previously, storytelling is a specifically liberal arts, literature-based focus, and computing and the internet was left to computer scientists or other technical professions. There was little scholarship that provided a link between the two, highlighting how storytelling techniques are being used by technological leaders to mislead and manipulate the public at-large, creating culture on the fly through digital artifacts. This study leans on creative writing, philosophical theories, social science, as well as cultural observations/scholars to critique and make apparent this manipulation in a variety of forms and styles. The findings of this research encourages awareness and understanding of how the modern internet operates via storytelling in an effort to teach readers on how to understand how this manipulation operates, identify where it exists, and ultimately, reject in the favor of truth.
Affecting retention: the relationship between intersectionality and students’ institutional experiences
(2021-03-17) Nguyen, Trung
The purpose of my study was to use an intersectional lens to understand the relationship between race and gender and institutional experiences in student retention at a selective predominantly White institution. I used Tinto’s (1993) longitudinal model of institutional departure as the foundation to understand students’ decision-making processes based on gender and race. Existing research emphasizes the roles that gender, race, and level of involvement play in student retention. The data I analyzed confirmed these previous findings and added the perspective of the intersectionality of race and gender in exploring students’ sense of belonging. Female students of color had the lowest mean scores related to a sense of belonging. Furthermore, the two factors most important to students developing a sense of belonging were validation and socialization. I applied a quantitative criticalist (Stage & Wells, 2014) approach and used the 2015 Diverse Learning Environments (DLE) Survey, developed by the Higher Education Research Institute, to explore any systemic inequities in educational outcomes at Southwest University. Researchers use the DLE survey to assess the capacity of their campus climate and culture to support a multicultural community towards retention and graduation. Examining the instrument through the lens of intersectionality produced more specific results. I used analysis of variance and hierarchical multiple regression to analyze the data. The results indicated that female students of color at a predominantly White institution are the most at risk of low retention and graduation rates. Consequently, I suggest that reform and changes to educational practices are necessary to increase the validation and socialization of female students of color. It is not enough for college administrators to simply recruit female students of color to college campuses to increase the diversity of the student population. Crucially, they must deliver on the promises made during the recruitment process by helping to provide an environment and culture at predominantly White institutions that support female students of color in thriving throughout their collegiate experiences until graduation.
Coloring, drawing, and water coloring to learn plant structures: Exploring pre-service teachers’ perceptions of botany lessons with art interventions
(2017-07-17) Patterson, Melissa E.
College level botany education in the United States is gradually being phased out of science and agriculture departments. The absence of botany courses creates a problem because there is an increasing need for trained botanist in the United States workforce, making it important to train teachers in botany so they can inspire the next generation of botanical scientists. Pre-service elementary teachers at a private university participated in three lessons utilizing three different art interventions to teach botanical structures (e.g. coloring sheets for leaf structures, drawing diagrams of flower structures, water coloring fruit structures). This study explores the students’ background in both science and art, perceptions of learning, emotional response, and how the lessons impacted the students’ perception of plants outside of the classroom. Qualitative methodology was used to open code students’ discussions while creating botanical representation and during a small group reflection at the conclusion of the lesson with scripted questions to guide the student’s conversations. Three themes emerged that were relevant to this study but not proposed as research questions, which included the nature of science, plant blindness, and anti-intellectualism. The students’ background and self-perceived level of artistry impacted their perception of learning and emotional response to the three lessons. The majority of students did not indicate a single art intervention that they perceived to help them learn botanical structures the best, however, the researcher observed that students seemed the most on task while drawing flower diagrams.
A passion for teaching science: A case study of five science teachers
(2021-03-26) Cordell, John Andrew
The modern psychological investigation of passion started with the study by Vallerand et al. (2003). The construct of passion has been applied to sports, gambling, and performing arts. The application of the construct of passion to the field of teaching has been very limited. This study uses Vallerand et al.’s definition of passion to consider the teaching of five science teachers. Using a case study methodology five teachers, who had been teaching for nine to sixteen years, were each interviewed twice, three of the five teachers provided a lesson plan that they had developed, about which they were passionate. I found that each of the participants was passionate about their craft, that each enjoyed being able to develop their own curricula, and that each participant valued peer collaboration and sharing of ideas as a means of professional development.
A frontier of ambition and intrigue: The neutral ground agreement and the Louisiana-Texas borderland, 1803-1824
(2024-08-26) Pearson, Jackson Wiley
“A Frontier of Ambition and Intrigue: The Neutral Ground Agreement and the Louisiana-Texas Borderland, 1803-1824” examines the Neutral Ground Agreement and the geopolitical struggle to define, observe, and enforce borderlines between Louisiana and Texas following the Louisiana Purchase. In November 1806, the Neutral Ground Agreement averted war between Spain and the United States by declaring the region between the Arroyo Hondo and Sabine River as neutral and outside the sovereign control of either Spain or the United States. My dissertation argues that the Neutral Ground was never truly neutral. Individuals on both sides of the borderland manipulated its existence to pursue their own interests and ambitions even when their schemes ran afoul of imperial designs. The ambitions, exchanges, and interactions between local populations in the Louisiana-Texas borderland amid this extended dispute demonstrate the limits of both state authority and notions of loyalty in the borderland as local populations sought to manifest their own desires in the borderland. Anglo Americans, French Creoles, Tejanos, enslaved people, Indigenous groups, and free blacks all sought to influence or manipulate the borderland tensions to their own desires or ambitions. This project demonstrates the limits of state authority in Early American borderlands and how local populations pushed imperial governments and militaries to engage with their own designs and desires. “A Frontier of Ambition and Intrigue” employs a borderlands history methodology to uncover cross-border connections that tied people, horses, and markets together across the region. This project offers intriguing insights into the pivotal role of local borderland populations in shaping the contours of imperial authority during the Early American Republic. Readers interested in Early America, Colonial America, and North American Borderlands will find this scholarship insightful in its approach to borderland commercial markets and state authority. In contrast to narratives of imperial authority, this project complicates borderland narratives in Early America by demonstrating fluid notions of loyalty and identity that resulted in conflicting commercial interests which defined cross-border markets and often defied imperial interests. This project seeks to join other borderlands scholarship emphasizing the power of local peoples to chart their own histories in contested spaces either to the support or detriment of imperial authorities in Early America.
Synthesis and characterization of RPy2N2 pyridinophane ligands and transition metal complexes as therapeutics and catalysts
(2024-08-06) Smith, Katherine Joyce
The pyridinophane family of macrocycles has been studied for decades as ligand scaffolds for metals towards a wide variety of applications including biological mimics, catalysts, and therapeutics A newer ligand scaffold to join the library, RPy2N2, introduces a second pyridine ring to the long-standing PyN3 scaffold. This work explores the effect of 4 position modification of the two pyridine rings of RPy2N2 on the characteristics of the ligand and the complexes of Cu(II) and Fe(III) for application as a SOD1 mimic and catalyst respectively. This work found that the modulation of the electronics of the 4-position substitution tuned the electronics of the ligand overall, as evidenced in 1H NMR shifts and protonation constants. This mirrored the trends seen with the 4-position substituted RPyN3 series, but beyond that the exchange of one secondary nitrogen atom for a pyridine ring vastly changed the behavior of the ligand scaffold, more than the electronics of the 4-position did. The pyridine ring is less electron-rich than a secondary amine nitrogen atom, the effects of which can be seen throughout the rest of this work. When metalated with Cu(II), the RPy2N2 series vastly outperformed the previously studied RPyN3 series as functional SOD1 mimics, resulting in the most active copper-based small molecule functional SOD mimic to date. The electron-withdrawing groups improved the activity, but the change in the ligand scaffold allowed for more drastic changes that greatly increased the activity of the [CuII(RPy2N2)]2+ complexes as SOD1 mimics. Similarly, the RPy2N2 ligand scaffold had such a great effect on the catalytic yields of the complex formed in situ between FeIII(OTf)3 and RPy2N2, that no difference could be seen between the different electronic substitutions. The ligand scaffold change increased the catalytic yield to the maximum possible yield for the model reaction in use, an improvement of at least 10% over the RPyN3 series. Additionally, it was seen that the RPy2N2 ligand series is capable of forming two distict species in solution with Fe(III), posited to be the monomeric and µ-oxo dimeric complexes, and that these complexes can interchange with each other with simple pH control. Altogether, this work focused on the functionalization of pyridine rings in RPy2N2 ligands and studying the effect of that functionalization on the activity of the ligands and the metal complexes.
The association between mattering and mental health in graduate students and faculty
(2024-08-06) Xiao, Jieming
Research has found that a sense of mattering, the perception that one is recognized and valued by other people and/or society, contributes to mental health and well-being (e.g., reduced burnout & stress). Although research has been done in undergraduate samples, little work has explored the psychological benefits of mattering in graduate students and faculty. Two studies examined the relation between mattering and mental health outcomes (e.g., satisfaction, stress, burnout) among graduate students (Study 1) and faculty (Study 2) at Texas Christian University (TCU). Results found that a sense of mattering was positively related to school/job satisfaction and negatively related to stress, burnout, depression, and quitting intentions in both samples. Additionally, research has shown that there may be some demographic differences on mattering. For example, women in male-dominated fields such as STEM (i.e., Science, Technology, Engineering, & Math) receive less recognition and credit for their work, which may contribute to a lower sense of mattering. The current research thus explored whether there was (a) a gender difference in the level of mattering between women and men for graduate students and faculty (separately), and (b) how area focus (i.e., STEM vs. non-STEM-related majors/careers) moderated potential gender differences. No significant effects emerged across the two studies. Implications of the current research is discussed in terms of the mental health and well-being of TCU graduate students and faculty.
The heterogeneity of autism spectrum disorder: An examination of child outcomes and parenting behaviors
(2024-08-06) Rafferty, Deborah
Background: Autism spectrum disorder (ASD) is a heterogenous neurodevelopmental disorder with defining characteristics of social communication/interaction challenges and restrictive, repetitive behaviors Many autistic children have difficulties with emotion regulation, which may lead to negative physiological and behavioral outcomes. Parenting behaviors may influence autistic children’s emotion and behavior difficulties, which then may impact parenting behaviors in the future. Examining these processes may provide better insight into interventions that may benefit autistic children and their parents. Further, these associations may be moderated by the heterogenous presentation of ASD symptoms and IQ. Method: Families (mother, father, and child) with an autistic child between the ages of 10 to 17 years were recruited to participate in a larger study. Participants completed a set of questionnaires at two time points six months apart. Child respiratory sinus arrythmia was also collected. Results: Latent profile analysis indicated a three-profile solution: 1) Average IQ-Moderate SA-Low RRB, 2) Average IQ-Moderate SA-Moderate RRB, and 3) Borderline IQ-High SA-High SA. Profile 3 had the lowest anxiety levels compared to Profile 1 and 3. Moderated regression analysis indicated at high levels maternal warmth, autistic children in Profile 1 had lower depressive symptoms. At high levels of depressive symptoms, maternal and paternal warmth was lower for autistic children in Profile 3. Discussion: Using latent profile analysis to determine if there were underlying subgroups in the population using IQ and ASD symptom severity as indicator variables, a three-profile solution was selected. Two of the profiles had average IQ with low to moderate symptom severity. The third profile had borderline average with higher ASD symptom severity. Results are consistent with prior research indicating the need to examine subgroups within ASD research. Child Effects and Parenting Effects models were partially supportive of a bidirectional relationship between parenting behaviors and child effect. More research is needed examining additional positive parenting behaviors.
Metal halide perovskites and selected investigations in defect passivation and energy/charge rransfer
(2024-08-06) Burnett, William Lovett
Metal halide perovskites (MHPs) are an emerging class of semiconductors with advantageous properties for use in applications such as light emitting diodes1 and photovoltaics.2 MHPs are made up of by three components in an ABX3 formula where A is a +1 cation such as methylammonium (MA), B is a +2 cation such as lead, and X is a halide anion such as bromide. MHPs take the perovskite crystal form which in the case of MAPbBr3 is cubic, with lead-halide octahedra [PbBr6]4- at the corners of the cube and the MA+ in the center. MHPs have a tunable bandgap,3 are solution processable,4 defect tolerant,5 and have shown high power conversion efficiency in solar cell devices.6 In this dissertation, high-pressure spectroscopy is used as a tool to investigate the effect of growing varying sizes of nanocrystalline MHP (7 nm and 4 nm) in a porous silica (pSiO2) matrix. As the crystal size decreases, the ratio of the number of atoms at the surface of the nanocrystal increases compared to the total number of atoms in the crystal, so if surface defects play a major role in MHP non-radiative recombination, the pressure-induced effects will be more apparent in the smaller nanocrystal. The photoluminescence (PL) and in selected measurement, the visible light absorption of the MHPs in pSiO2 were monitored as a function of pressure. MAPbBr3 grown within a 7 nm pore size pSiO2 showed a novel blue shift to higher energy light emission under high-pressure when compared with the bulk MAPbBr3. The MAPbBr3 grown in 4 nm pore size pSiO2 was relatively insensitive to increasing pressure. It is apparent that the size and shape of the host material largely impacts the pressure induced shift in PL emission. Energy/charge transfer between porous silicon (pSi) and prefabricated ligand passivated MHP quantum dots (QDs) was investigated using PL quenching experiments. The PL intensity and lifetime of the QDs was measured as the concentration of the pSi is added and a Stern-Volmer model is used to elucidate the mechanism of interaction. The Stern-Volmer plots showed a mixture of both static (irreversible complex forming) and dynamic (collisional) mechanisms in solution.7 The surface area, surface chemistry and pore size of the pSi has a large impact on the PL lifetime and intensity quenching due to accessibility to the surface of the pSi by the QDs and the interaction of the QD with the surface. It is inferred that a Förster resonance energy transfer mechanism is occurring due to the collisional nature of the interaction between pSi and MHP with the ligand passivation preventing intimate interaction of the MHP and pSi. Large triazine based organic macrocycles were investigated for defect passivation in MHP thin films. Lewis bases are common defect passivating agents in MHP synthesis with oleylamine being commonly used in colloidal nanocrystal formation.8 Triazine based Lewis bases can occupy defect sites and improve the optoelectronic properties of the MHP. Our hypothesis is that large organic macrocycles can ideally add stability to a given MHP film and be tailored to have different passivating moieties, in this case a 24-member triazine macrocycle with a butyl amine functionality. The addition of the triazine based macrocycle containing the amine functionality to MHP thin films showed a fivefold increase in the PL intensity and significant narrowing of the emission linewidth of the MHP thin film in contrast to a macrocycle with a valine moiety that does not provide passivating effects. Overall, physiochemical manipulation of charge transfer, defect passivation, and high-pressure probing of surface defects in MHPs were shown in this dissertation. It is apparent that the MHP semiconductor is influenced greatly by the interfacial environment and that it can be optimized for use in LED’s and PV devices with novel bandgap tunability, a better understanding of charge transfer between pSi and MHPs, and tailored defect passivation of thin films, many challenges remain however.
A praxiological curriculum for a black church to resist voter suppression
(2024-07-25) Moses, Patrick Dewan
I contend that a Black Church has the liberative power to overcome voter suppression tactics created by legislative action. This for-ministry project provides Elm Grove District Association affiliated Black Baptist Churches with a creative, practical solution to resist voter suppression. In Texas, as in each of the fifty states in the U.S., local governments manage election administration. County election officials delegate voting to volunteers. During the Civil Rights era, many Black churches served as primary institutions to register African Americans who had been prohibited from the ballot box by southern states' Jim Crow laws. By replicating the Rev. James M. Lawson's historic tenet of nonviolent resistance, which is voting, a Black Church possesses the prophetic presence to resist the sin of voter suppression. Using an inductive pedagogical approach, I created a praxiological curriculum for a Black Baptist Church to recruit and empower (sponsor) members to become Volunteer Deputy Registrars (VDR). An empowered VDR registers voters and practices other proactive actions, such as informing the community about upcoming elections and changes to the election laws and preparing new voters to engage in the sacred, democratic act of voting. Through congregational input, an empowered VDR develops and executes an Action Plan or Voting Strategy that helps the Black Church resist voter suppression in their community.
The interaction of language, executive functioning and structured physical activity for children at risk for secondary communication disorders
(2024-05-08) Mattingly, Jessica
This three-manuscript dissertation evaluates how the domains of language, executive functioning and physical activity interact for children with communication disorders, and how those domains may differentially influence development across different etiologies. The first study explores the relationship between executive functioning and language in children who are deaf and hard of hearing. Parent reports of inattention and hyperactivity are related to child language knowledge and fatigue. The second study evaluates the impact of introducing movement to word learning instruction for children with Down syndrome. More words were learned in the movement condition than in a business-as-usual teaching condition. The third study combines all three domains across etiologies of hearing loss, Down syndrome, and typical development. Results indicate that etiology does impact outcomes in these domains. Executive functioning predicts language outcomes for all children, and etiology impacts this relationship. Further, physical activity interacts with executive functioning skills to strengthen language. The findings of this dissertation have implications for differentiated language interventions according to disability and incorporation of multiple domains.
Border checkpoints: a rhetorical analysis
(2024-03-18) Cano, José Luis
Migration shapes the US-Mexico border, which leads to an oversaturated presence of US Border Patrol. At the interior border checkpoint, Border Patrol agents stop vehicles, interrogate drivers and passengers on citizenship status, and inspect these vehicles and occupants. I frame the interior border checkpoint as a metonym of warfare at the border via immigration enforcement to investigate the contentious yet symbiotic relationship between citizenship and enemyship. During rhetorical exchanges at the checkpoint, Border Patrol agents base their assessments of citizenship and enemyship on markers of race, language, class, and gender. To investigate the border checkpoint, I define rhetoric as a force that captures to account for the mechanisms at this site that lead to an imaginative, legal, and material capture. I examine the textual, physical, and metaphysical activity that animates and disrupts the checkpoint: Supreme Court cases, author-captured photographs, and archives of la Llorona subverting immigration enforcement.
Neural and musculoskeletal adaptations to acute and chronic training in athletic populations
(2024-05-10) Voskuil, Caleb Christian
Introduction: Athletic populations are underrepresented in literature, with a majority of studies examining the effect of acute and chronic training in untrained individuals. The training adaptations gained following resistance or endurance training may alter performance, specifically, the inherent fatigue resistance observed in females. However, limited data exists examining sex differences in fatigue during dynamic muscle actions commonly performed during resistance training. Therefore, this dissertation examines neuromuscular responses between sexes during acute resistance exercise in resistance- and endurance-trained athletic populations. Additionally, this work identifies the musculoskeletal adaptations that occur across a year of training in Collegiate Division 1 football players. Methods: Three studies were completed in highly trained, athletic populations, examining neuromuscular differences in males and females during acute training in the upper body and lower body, and musculoskeletal adaptations to chronic training in Collegiate Division I football players. The first study utilizes electromyography (EMG) to examine neuromuscular responses during acute resistance exercise and subsequent isometric force production of the elbow flexors in a resistance-trained population. The second study uses EMG and ultrasonography of the knee extensors and examines neuromuscular responses during acute resistance exercise and subsequent isometric force production in an endurance-trained population. The third study identifies musculoskeletal adaptations in Collegiate Division 1 football players across the 2023 year. Results: At the same relative intensity (50% 1RM), resistance-trained females demonstrate statistically significant greater fatigue resistance in the elbow flexors, quantified by a greater number of repetitions performed (M: 48.3 ± 6.1; F: 64.9 ± 12.3), greater subsequent isometric strength maintenance (M: 69.8%; F: 76.1%), and greater relative biceps brachii EMG amplitude (M: 98.6 ± 31.1%; F: 125.8 ± 36.9%) compared to males. However, endurance-trained males and females demonstrate no difference in the number of repetitions performed (M: 69.3 ± 17.1; F: 72.6 ± 26.5) or subsequent isometric force produced (M: 86.6%; F: 88.1%) during knee extension. Despite the lack of performance differences, females demonstrate greater maintenance of relative rectus femoris EMG amplitude (M: 73.38 ± 6.39%; F: 93.23 ± 5.61%) compared to males during the knee extension task. Lastly, Division 1 Collegiate football players demonstrate significant changes in lean mass and fat-free mass index (FFMI), observing increases (177.0 ± 24.5 lbs; 24.1±2.1 kg/m2) and decreases (172.6 ± 25.3 lbs; 23.5 ± 2.3 kg/m2) that corresponds with increased or decreased training volume, respectively. This occurred without a significant change in body fat percentage (16.5 ± 7.4% to 17.2 ± 7.6%) or body weight (226.5 ± 48.5 lbs to 223.2 ± 49.3 lbs). However, bone mineral composition significantly increased (9.2 ± 1.2 lbs to 9.4 ± 1.3 lbs) and Achilles tendon echo intensity decreased (123.8 ± 15.7 a.u. to 99.64 ± 17.3 a.u.), while Achilles tendon thickness generally maintained size (0.47 ± 0.08 cm to 0.50 ± 0.06 cm) regardless of changes in training volume. Conclusions: Sex differences in acute resistance training fatigue are more pronounced for the upper limbs compared to the lower limbs. Additionally, similar neuromuscular responses are observed between males and females for the knee extensors, unlike that shown for the elbow flexors. Collegiate Division 1 football players present significant lean mass changes due to alterations in training, demonstrating modifications in lean mass despite chronic training experience. This dissertation presents novel information regarding prior training experience on acute resistance training fatigue between males and females. Additionally, novel insights are shown for the effect of training over a year of collegiate football on musculoskeletal variables and emphasize the use of FFMI and Achilles tendon ultrasonography in collegiate football players. This data shows the neuromuscular and musculoskeletal responses to acute and chronic exercise training in athletic populations.
Frustrative nonreward and the basal ganglia: role of outputs from the nucleus accumbens in reward loss
(2024-05-06) Hagen, Christopher
Mammals in general experience bouts of negative emotion when they unexpectedly experience a reduction in expected reward, known as unexpected reward downshifts (URDs). The specific biological and psychological mechanisms which have evolved to respond to downshifted rewards with behaviors related to anxiety, conflict, and even pain, are known collectively as frustration. The present set of experiments examined three neural pathways in and their role in the frustration response to URDs. Using a double-infection chemogenetic manipulation procedure, neurons originating in the nucelus accumbens (NAc) and synapsing onto the globus pallidus externus (GPe), globus pallidus internus (GPe), or ventral pallidum (VP), were activated during key moments in a reward loss paradigm. Animals were trained with 32% sucrose and downshifted to 2% sucrose. It was found that exciting the pathway between the NAc and GPe had no effect on their response to being downshifted, whereas activating either the pathway between the NAc to GPi or the pathway from the NAc to VP caused a significant increase in consummatory suppression and exacerbation of the frustration response. All these effects were in the absence of any gross motor effects shown in an open field. Overall, these findings provide new insights into how animals process the emotional value of rewards when their expectations are violated.
Diagram driven computer generation of equation-of-motion coupled cluster equations for perturbed quantum oscillators
(2024-05-06) Huey-You, Carson
We consider a set of quantum harmonic oscillators subjected to perturbations expressible as a power series in position and momentum. A diagrammatic scheme is developed, by which to generate equation-of-motion coupled cluster (EoM-CC) equations for the calculation of the perturbed energy spectrum of the system. The diagrammatic scheme is then adapted into a Python code, capable of generating the necessary equations and computer code associated with any arbitrary order of the perturbation and coupled cluster excitation levels. The generated equations are made readily accessible for numerical evaluation, alongside convergence schemes and the application of iterative Bogoliubov transformations.
The power we hold: sharing the stories of girls of color
(2024-05-08) Jones, Cara S
Using critical race feminism and moral transformative leadership, this qualitative, participatory study works to share the perspectives of girls of color in public schools in the United States. Further, this study explores the importance of gathering student voices and utilizes participant data analysis to honor the lessons we learn from students. This study underscores the need for school leaders to engage in more participatory methods to be more intentional about inviting student voice and participatory methods into educational leaders’ decision making.

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