bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and preliminary validation of multidimensional life satisfaction of internal migrant workers' children in China
Authors:   , Liu Jingfei
Published: February 2023

Background Internal labor exporting in China has been a common phenomenon, more and more people from rural area of China migrant to cities for jobs, which leads to the unavoidable social situation of left-behind and migrant children. Research has been focusing on the negative influences on these groups of children, while my research attempted to develop a scale to measure their satisfaction of life. I estimate life satisfaction of my target group from 6 domains: friend, school, living environment, self, material, and family. The items in family domain are different for children who live with both of parents and children who don't live with both of parents. Method I collected data for two rounds. In the first round, only my proposed life satisfaction scale for migrant workers' children was used. Confirmatory factor analysis (CFA) and Exploratory factor analysis (EFA) were used to detect underlaying factors, model fitting criterions such as root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker-Lewis index (TLI), and item loading values' criterions are used to eliminate items. In the second round, the adjusted scale was applied, as well as Student Life Satisfaction Scale (SLSS), Self- Description Questionnaire-II (SDQ-II), and Positive and Negative Affect Schedule (PANAS) for validity estimating. McDonald's Omega was used for reliability estimation. Measurement Invariance between groups was also tested. Latent means of different groups were compared. Result The adjusted life satisfaction of internal migrant workers' children scale contains 31 items for each group. McDonald's Omega showed acceptable values for every domain in two groups. Validity evidence can be seen from: my scale can be distinguished from SLSS and PANAS. Domains in my scale and the overall score also can predict global life satisfaction. The correlations between overall score of my scale positively correlated with scores of different domains of SDQ-II. Measurement invariance testing shows measurement invariance between children live with or without both of parents/males and females/being only child or not on configural, scalar and metric levels. Latent mean comparison shows that children who live with both parents have higher life satisfactions in the domains of friends, living environment, and self. In the sample of children who live with both of their parents, boys have less life satisfaction of family, while children who are only child(ren) have a higher life satisfaction of friends. Conclusion A six-domain specific scale of internal migrant workers' children in China was developed and preliminarily validated in this study.
A Bayesian approach to data-driven discovery of nonlinear dynamic equations
Authors:   , North Joshua S.
Published: February 2023

Dynamic equations parameterized by differential equations are used to represent a variety of real-world processes. The equations used to describe these processes are generally derived based on physical principles and a scientific understanding of the process. Statisticians have embedded these physically-inspired differential equations into a probabilistic framework, providing uncertainty quantification to parameter estimates and model specification. These statistical models typically rely on a predefined differential equation or class of models to represent the dynamics of the system. Recently, methods have been developed to discover the governing equation of complex systems. However, these approaches rarely account for uncertainty in the discovered equations, and when uncertainty is accounted for, it is not for the complete system. This dissertation begins with a statistical model for the seasonal temperature cycle over North America, where the dynamics of the system are parameterized by a specified functional form. The model highlights how the seasonal cycle is changing in space and time, motivating the need to better understand the driving mechanisms of such systems. Then, a statistical approach to data-driven discovery is proposed, where uncertainty is incorporated throughout the complete modeling process. The novelty of the approach is the dynamics are treated as a random process, which has not be considered previously in the data-driven discovery literature. The proposed approach sits at the junction between the statistical approach of incorporating dynamic equations in a probabilistic framework and the data-driven discovery methods proposed in computer science, physics, and applied mathematics. The proposed method is put into context within the broader literature, highlighting its contribution to the field of data-driven discovery.
Novel methods of evaluating materials in extreme environments
Authors:   , O'Donnell Valentina
Published: February 2023

Three novel experiments were completed to investigate the difference in radiation response between production methods of Inconel 625. Production methods explored were the laser-powder bed fusion additive manufacturing method and the more conventional production method where samples were cut from a plate of wrought material. The experiments carried out aimed to further the understanding of how samples of this alloy, produced by AM methods, differ in radiation resistance from samples produced by conventional methods. The first experiment looked at the differences when subjected to a proton beam, while the other two experiments looked at the differences that resulted from neutron radiation environments. Differences in the effects of the irradiations on the hardness and microstructure were compared between the different manufacturing methods. The first experiment used the ion beam of a cyclotron to impart damage onto a metal target, then located that damage using nanoindentation. The second experiment used fast neutrons from a PET isotope production machine to irradiate metals for damage studies, proving that the technique yields measurable results even at low fluence irradiations. The third experiment used the neutron field in the University of Missouri Research Reactor to irradiate nanogram-scale flakes of metal and compare them to samples approximately nine orders of magnitude larger, on the order of a gram. These smaller samples were able to be analyzed sooner and were safer to handle while showing similar radiation response as compared to the larger samples.
Healing while Black in the U.S.: adverse childhood experiences, ethnic identity, psychological sense of community, and complete mental health of emerging adults
Authors:   , Onwong'a Jana Robina
Published: February 2023

The present study drew on the Phenomenological Variant of Ecological Systems Theory (PVEST) to investigate the impact of socioecological factors on the mental health of Black emerging adults in the United States. Specifically, the sought to explore the relationship between ethnic identity and psychological sense of community (PSoC) to each other, the relationship between adverse childhood experiences (ACEs) to complete mental health (CMH), and whether both ethnic identity and PSoC would serve as possible protective factors to support the mental health of Black emerging adults who experience negative effects ACEs. The results suggest the relationship between ethnic identity and psychological sense of community was significant and positive and the relationship between adverse childhood experiences and complete mental health was significant and negative. The results also suggested that ethnic identity seemingly buffered the negative relationship between ACEs and CMH and that PSoC also seemed to buffer the negative relationship between ACEs and CMH. Examples of implications included considering the results to inform educational curricula as well as culturally affirming, attuned, and sustainable prevention and intervention strategies to mental health care. A few limitations to the research process included self-report, survey attrition, and not exploring within group differences. Future directions for research include but are not limited to, exploring additional moderators of ACEs on Black youth's mental health outcomes, and updating ACEs-related instruments to include racism and racial discrimination or using updates measures that can capture the psychological impact of elements related to systemic oppression and state-sanctioned violence on Black people.
Barriers to adoption of precision agriculture competencies in secondary agriculture education programs: a case study
Authors:   , Reynolds Chad
Published: February 2023

Precision agriculture has the ability to increase production, reduce costs, increase returns, and reduce environmental impacts if adopted and implemented successfully. Which is why the successful adoption and implementation of precision agriculture technologies and practices is imperative to the future of agriculture. The future of the agriculture industry starts with secondary agriculture education students and learning about precision agriculture technologies and practices used in the agriculture industry within secondary agriculture education programs will better prepare them for the world they are to inherit. The purpose of this study was to describe [STATE] secondary agriculture science teachers' barriers to adopting precision agriculture competencies. Ten secondary agriculture science teachers were selected for the study using purposeful sampling. Semi-structured interviews were conducted, and triangulation occurred using observations and document analysis. The constant comparative method of analysis was used to develop holistic themes. Teachers indicated the importance and relevance of precision agriculture, but none of the participants in the study have decided to fully adopt precision agriculture in their curriculum. The decision-making process and the reasons teachers make the decision to adopt or not adopt precision agriculture competencies were explored. Four barriers to adoption of precision agriculture competencies were revealed and include the lack of time, the lack of equipment and/or funding, the lack of curriculum, and the lack of knowledge.
Modeling state duration and emission dependence in hidden Markov and hidden semi-Markov models
Authors:   , Rojas Salazar Shirley
Published: February 2023

Hidden Markov models (HMM) are composed of a latent state sequence and an observation sequence conditionally independent on the states, which follows an emission distribution. Hidden semi-Markov models (HSMM) extend the HMM by explicitly modeling the duration in the states. This dissertation expands the HSMM by introducing non-homogeneity in the duration model, with duration parameters defined as functions of time-varying covariates, which has not been considered to date. This model is applied to high-frequency environmental data. The variable transition HMM (VTHMM) also expands the HMM by considering the duration in the state transition probabilities. We present a VTHMM for team sports data to obtain inference on the dynamic network of players in a game, and model high temporal resolution player location data. Lastly, the conditional independence assumption in the emission distribution can be violated, in particular with high-frequency data. We propose two novel approaches to address the conditional dependence, by introducing data subsampling in the MCMC sampling algorithm for parameter inference in HMMs and HSMMs, and by considering basis function expansions in the emission distribution.
Parental psychological factors of mother-child and father-child reminiscing about negative and positive emotional past experiences
Authors:   , Xu Nanxi
Published: February 2023

Little is known about the significance of parent factors, including attachment representations, depressive symptoms, and personality, in shaping parental elaborative reminiscing, as research has primarily examined child factors for parental reminiscing. Moreover, the majority of research comprises samples of mothers and children, and thus, little is known about the predictors of father-child reminiscing. The current study therefore examined the significance of parent predictors of mothers' (N = 60) and fathers' (N=47) elaboration about past emotional experiences. Mothers higher on deactivation were less elaborative during the hurt event, whereas mothers higher on hyperactivation exhibited more emotion elaboration and greater levels of elaboration when reminiscing the hurt event. Mothers higher on depressive symptoms were more elaborative during the scared event. Fathers higher on positive personality exhibited more emotion elaboration and greater levels of elaboration when reminiscing the scared event. These findings indicate that attachment history and current mood are linked with mothers' (but not fathers') elaboration, whereas more stable personality characteristics are linked with fathers' (but not mothers') elaboration. Findings advance knowledge of the significance of parent factors for their elaboration styles, by indicating that maternal elaboration might be more nuanced to child and contextual cues, whereas paternal elaboration, by contrast, might be more heavily influenced by stable trait characteristics, such as personality.
A quantitative evaluation of DNA damage from irradiation of feline oral squamous cell carcinoma cells
Authors:   , Ashworth Hayley L.
Published: February 2023

Feline oral squamous cell carcinoma is a locally invasive neoplasm that continues to carry a poor prognosis despite advances in multimodality oncologic treatment. Location, completeness of surgical excision or complete response to radiation therapy at day 30 have been shown to be predictive of survival. Tolerable treatment with radiation and concurrent chemotherapy has been described, but the ideal radiation protocol has not been determined. Though risk factors and prognostic indicators have been identified, there is no test to predict outcome prior to treatment. Three feline oral squamous cell lines (SCCF1, SCCF2, SCCF3) were used to investigate the potential of the alkaline comet assay to predict radiosensitivity. The three cell lines were irradiated with 6 MV photons and initial DNA damage using percent DNA in the comet tail and comet tail moment were plotted against all doses (0 - 9 Gy) for each cell line. There was a significant difference between the means of SCCF1 cells that received 0 Gy and 9 Gy (p=0.019), as well as 3 Gy and 9 Gy (p=0.022) when assessing the DNA in the tail. The difference between the means for comet tail moment was significant for SCCF1 at 0 Gy and 9 Gy, which corroborates part of the previous finding. Based on other experiments that evaluated clonogenic and comet assays together, correlation between the greatest mean tail moment and lowest surviving fraction indicate radiosensitivity, not cytotoxicity. The clinical feasibility of performing the comet assay on FOSCC tumor biopsies to elucidate radioresponsiveness prior to initiating treatment remains questionable for this specific disease. Performing the comet assay to evaluate DNA repair capabilities is recommended at various time intervals after irradiation to optimize fractionation protocols. Validation of DNA damage from double-stranded breaks could be compared using a chemiluminescent assay to detect levels of mouse anti-human monoclonal antibody for γ-H2AX.
Micaceous mindsets: chemical characterization of Pueblo IV utility wares at multiple sites along the Rio Grande
Authors:   , Burgess Blaine K.
Published: February 2023

Micaceous utility wares are commonly found at Ancestral Pueblo villages along the Rio Grande and adjacent areas, yet they have received comparatively little attention relative to the well-studied glaze wares with which they often share contemporaneity. Compositional studies show that glaze wares and their ingredients were often transported around the landscape, driven by a mix of ritualistic and economic factors, but utility wares were also a common component of daily Pueblo activities and are shown to have been involved in complex exchange schemes. Neutron activation analysis is used to chemically characterize micaceous utility sherds from six Pueblo IV (1300 - 1600 CE) sites between Santa Fe and Socorro, New Mexico. Five distribution patterns are recognized based on spatial patterns of compositional groups present within and shared between sites. These indicate procurement and/or manufacturing similarities between the Rio Puerco and the Albuquerque area, and differences to the north near the Jemez Mountains and to the south in the Rio Abajo. These trends are meant to help focus future compositional, geological, and petrographic research.
Dystrophic cardiomyopathy: the role of myofilaments
Authors:   , George Thomas G.
Published: February 2023

Dystrophic cardiomyopathy is the consequence of diseases that affect the protein dystrophin. Dystrophin forms part of the dystrophin glycoprotein complex and is postulated to act as a membrane stabilizer, protecting the sarcolemma from contractioninduced damage. Duchenne muscular dystrophy (DMD) is the most severe dystrophinopathy, caused by a total absence of dystrophin. Patients with DMD present with progressive skeletal muscle weakness and due to advances in treatment, which increase life span, a cardiac component of the disease has been unmasked. Many patients with DMD now succumb to heart failure. As such this study aims to address a knowledge gap relating to the cardiac myofilament involvement in DMD. To assess the effects of DMD upon cardiomyocyte function, isolated permeabilized cardiomyocytes of wild-type and DMDmdx-4cv mice were attached between a force transducer and motor and subjected to a range of contractile assays. Maximal tension and force development rates (indexed by the rate constant, ktr) were similar between the wild-type and DMDmdx-4cv cardiac myocyte preparations. Interestingly, it was found that DMDmdx-4cv cardiac myocytes had a greater sarcomere length dependence of peak power output when compared to the cardiac myocytes of wild-type littermates. These results suggest dystrophin mitigates length dependence of activation and augmented sarcomere length dependence of myocyte contractility which may accelerate the progression of ventricular myocyte damage in dystrophic hearts. Following this first study, the effects of mavacamten, a novel small molecule modulator of the thick filament activation, were assessed upon contractile properties in wild-type and DMDmdx-4cv murine permeabilized cardiomyocytes. Mavacamten decreased maximal tension and ktr in both wild-type and DMDmdx-4cv cardiomyocytes, while also normalizing the length dependence of peak power between DMDmdx-4cv cardiac myocytes and wild-type preparations. These results highlight the potential benefits of mavacamten (i.e., reduced overall contractility while maintaining exquisite sarcomere length dependence of power output) as a treatment for dystrophic cardiomyopathy associated with DMD.
Manipulating forest structure and ground flora composition for the restoration of oak woodlands and the reconstruction of oak savannas in Central Missouri
Authors:   , Maddox Dacoda T.
Published: February 2023

Managers across the central US are interested in restoring once abundant ecosystems such as savannas and woodlands. These restorations are inundated with challenges like creating the appropriate native plant structure and composition. This project will evaluate methods to 1) reintroduce woody structure to a restored prairie to create a savanna, and 2) establish native woodland ground flora in a recently thinned mature oak stand for woodland restoration. Savannas require frequent fire for maintenance; as such, newly planted trees in a prairie will require protection from frequent fire. For our first project objective, we planted 900 oak (Quercus) seedlings of five species grown by two nursery production methods [containerized root production method (RPM) or bare-root] and used weed barriers and a mechanical fuel removal treatment to protect them. Species and stock type selection were the most important treatments in establishing oak trees in a restored prairie, while the mechanical fuel removal and weed barrier treatments had little effect. Returning a degraded oak forest to a woodland community may require active seeding of woodland ground flora and seedbed manipulation due to a depauperate seed bank and low potential for desired species to colonize the site. For our second project objective, establishing ground flora in structurally restored woodlands, we seeded a diverse mix of native herbaceous species that have various light tolerances on plots of varying overstory tree density where the litter was either raked or not. Reduced basal area, seeding of native ground flora, and time since treatment were significant for increasing abundance, diversity, and the quality of the plant community, while raking had little effect.
Media's impact on political polarization in the family
Authors:   , Schroeder Makenzie
Published: February 2023

Are we all in this together? Around 87 percent of Biden voters and 95 percent of Trump voters can at least agree on the answer to this ever-pressing question: no, we are not (Pew Research Center, 2020). Americans are increasingly divided, with a nearly even split of people believing President Joe Biden can create unity and those who have little or no confidence in his ability to do so (Pew Research Center, 2021a). Political polarization in the United States is on the rise (Iyengar and Westwood, 2015), and recent scholarship suggests that as polarization increases, its strain on familial ties becomes more acute (Afifi et al., 2019; Chen and Rohla, 2018). Extant research has demonstrated a clear link between polarization and family, and polarization and news media, but the relationship between the three constructs has thus far gone relatively unexplored. Taken together, the worsening polarization among partisans, particularly those consuming attitude-consistent media (Stroud, 2010), suggests the need for research exploring the possibly polarizing effects of political news media exposure on familial ties. The present study aims to fill this gap in the literature. Using social identity theory (SIT; Tajfel and Turner, 1979) as a theoretical lens, this study examines how exposure to distinct forms of partisan media can lead to differential polarization effects depending on political heterogeneity within the family and relational satisfaction.
The effects of state term limits on natural resource spending
Authors:   , Shipp Olivia Claire
Published: February 2023

This paper examines how term limits operate as an institutional characteristic of state legislative branches. First, I describe the history of the term limit movement to contextualize public opinion. I then review relevant literature that explores the effects of term limits on legislatures, legislators, and legislation. The cited literature suggests that term limits may amplify decreased spending in natural resources. I test that hypothesis using two different models. The first is a linear model and the second is a difference-in-difference model. My empirical analysis suggests that term limits do decrease natural resource spending, but I cannot confirm a causal relationship. This result suggests that the effects of term limits may be more superficial than proponents and opponents suggest.
Characteristics of pretend play and their contributions to preschool children's emotion regulation
Authors:   , Wilson Alaina
Published: February 2023

Research on the benefits of pretend play for children demonstrates that engaging in this non-literal style of play is linked with better emotional skills (Lindsey and Colwell, 2013). While this relation between pretend play and emotional development is evident, the mechanisms driving this process are not well understood. The present longitudinal study used video observations to examine whether specific aspects of pretend play (emotional expression and social interaction) were related to improvements in children's emotion regulation. Contrary to hypotheses, there was a negative relation between social pretend play engagement and emotion regulation outcomes that approached significance. Additional research is needed that uses multiple informants of children's emotional self-regulation and examines other possible mechanisms to clarify how these constructs are linked in early childhood.
COVID-19 compliance across societies: testing health messaging models in the U.S. and Kingdom of Saudi Arabia
Authors:   , Alhugbani Hessah F.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] The purpose of this study is to test the theories of communication about health crises and theories of persuasive health communication that have been applied to COVID-19 in a different cultural context in order to understand these theories need to be adapted for a global pandemic. In order to explore this realm, the conceptual framework established by the health belief model is expanded by adding two components. The first component is to understand the role of authoritarianism and the way it interacts with psychological reactance. The second component is to understand the role of collectivism in the way it interacts with the subjective norms component of the integrated model. By utilizing message cues, this study used an experimental design to empirically test whether using the norms and authoritarianism cues affect behavioral intentions to follow government-enforced health policies to contain COVID-19. The findings of this study indicate that the authoritarian cue generated psychological reactance in both cultural contexts; the Western and undemocratic. This suggests that psychological reactance goes beyond being related to a specific cultural context. Furthermore, I found that social norm manipulation may not be able to break through peoples' actual perceptions of what members of their community think. The results of this study led to conclude that cultural differences do exist, but the tools to theorize about these differences need to be developed and refined. The findings reported in this study highlight contributions to the use of theories of communication about health crises and theories of persuasive health communication in non-Western contexts in both research and practice.
The effects of VR game-based learning on students' computer programming self-efficacy engagement, and the development of computational thinking
Authors:   , Bueno Vesga Jhon Alexander
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Computational thinking helps students solve problems by applying concepts drawn from computer science. One of the most popular strategies to develop computational thinking is to solve computer programming problems using block-based coding commands. One way to engage students in solving programming challenges is by embedding them in digital games. Game-based learning is gaining popularity in the educational community due to its ability to integrate knowing and doing in a situated virtual environment. In addition, the affordances of virtual reality (VR), like high-resolution 3D graphics and a highly immersive environment, make this technology promising for developing games intended to help high school students develop computational thinking featuring a quantitative research approach. A review of the literature reveals that the use of VR game-based learning to develop computational thinking in school-age students is still in the early stages. It also shows that the results obtained in empirical studies so far have been inconclusive. This study tested the effects of VR game-based learning on students' computer programming self-efficacy, engagement, and the development of computational thinking. A total of 73 high school students participated in the study. Participants filled out pre-test questionnaires and a test, played a VR coding game, filled out questionnaires at two moments of the game time, and then filled out post-test questionnaires and a test. The results showed that students exhibited significantly higher computational thinking scores after playing a virtual reality coding game. They also showed that their computer programming self-efficacy levels increased significantly as the level of difficulty also increased while playing the game and that their levels of engagement remained constant throughout the game. The current study deepened the understanding of using a VR game-based learning strategy to develop computational thinking in high school students and the role of computer programming self-efficacy and engagement when developing computational thinking using VR games.
Protein-DNA interaction prediction and protein structure modeling by machine learning
Authors:   , Chen Chen
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Proteins are large, complex molecules that perform most essential functions within organisms. In this work, we mainly focus on two important aspects that determine their functional properties: the tertiary structure of the proteins and their interaction patterns with the genome. Understanding these properties brings valuable insights on the fundamentals of biology and result in new applications in areas such as agriculture, precision medicine, and drug discovery. The recent developments of bioinformatics and structural biology, machine learning, in particular deep learning has proven to be extremely powerful in inference and interpretation of experimental observations by taking advantage of the large amount data publicly available today. We aim to propose novel machine learning frameworks that can both extract information from higher-level features, and provide explainability for meaningful insights beyond the predictions as well. However, due to the volatility of biology phenomena, the design of data processing and modeling need to be extensive for features from the the proteins. Also, the different geophysical measurements (1D, 2D and 3D) of the protein properties bring new challenges for the selection of model architectures that can effectively leverage different forms of data structure. In this dissertation, four major contributions are described. First, DeepGRN, is a method for transcription binding site prediction using 1D transformer-based network. Second, GNET2, is a data-assisted method to infer the interactions between proteins and genes from gene expression data using decision tree and information theory. Third, ATTContact, is a tool for protein contact prediction based on 2D residual neural networks with attention mechanism. Finally, EnQA, a method based on 3D equivariant graph networks for protein model quality assessment and selection of the most accurate model as the final protein structure prediction. All the methods described have been released as open source software, and are freely available to the scientific community.
Evident yet opaque: a defense of the evaluative normativity of logic
Authors:   , Cruz Duke J.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] The research in this dissertation concerns the philosophy of logic. More specifically, it concerns the normative status of deductive logic. Many philosophers and logicians have thought that logic tells us how we ought to reason. Let us call the claim that logic is normative for reasoning the Basic Normativity Thesis (BNT). This thesis has enjoyed widespread acceptance until relatively recently with the work of Gilbert Harman (1984, 1986, 2009), Gillian Russell (2017) and others, who show that this thesis is not as obvious as it would appear. My central dissertation thesis is that (NTE*) logic is evaluatively normative for deductive reasoning, where this means that logic evaluates deductive reasoning for correctness. I argue for this thesis by using a methodology that has been adopted by other leading researchers in the area. This methodology tests bridge principles against a set of adequacy conditions. A logical norm, or, equivalently, a bridge principle, connects logical validities or logical invalidities with norms regarding belief, disbelief, or degrees of belief. In general, if a bridge principle is adequate, then it will show how logic is normative for deductive reasoning. Thus, in defending my dissertation thesis, I defend my own set of bridge principles. In sum, in this dissertation, it will be argued that logic is evaluatively normative for deductive reasoning.
Ventricle-specific fibrotic cardiac remodeling in the progression of heart failure with preserved ejection fraction
Authors:   , Kelly Shannon C.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Heart failure with preserved ejection fraction (HFpEF) is currently the most prominent form of heart failure (HF). Despite the rising prevalence over the last few years, the pathogenesis of this disease is still unknown. Therefore, the focus of this dissertation is to investigate the molecular pathogenesis of fibrotic cardiac remodeling in swine models of HFpEF as cardiac fibrosis is a hallmark feature of this disease and hypothesized to be involved in its pathogenesis. Fibrotic cardiac remodeling can occur when there is a dysregulation between the synthesis and degradation of extracellular matrix (ECM) proteins. Additionally, the focus of this dissertation is to evaluate fibrosis in the left and right ventricles as right ventricle (RV) dysfunction can increase the risk of mortality up to 80 percent in individuals with HFpEF. Overall the goals of this dissertation are two-fold. First, to evaluate RV remodeling in a cardio-metabolic swine model of HFpEF. Second, to investigate the differences between the regulation of cardiac fibrosis in left ventricle (LV) and RV in a swine model subject to chronic pressure overload and/or the loss of female sex hormones. With the cardio-metabolic swine model, RV transcriptome analysis identified MAPK8/JNK1 as a hub gene associated with ECM remodeling that included an increase in fibronectin in the right coronary artery (RCA). This increase in fibronectin was potentially due to a regulatory imbalance between JNK and matrix metalloproteinase-14 (MMP-14). Additionally, this increase in fibronectin was associated with an increase in vascular stiffness. With the second goal of this study, it was demonstrated that the regulation of cardiac fibrosis occurs in a chamber-specific manner. In the LV, there was an increase in total collagen levels due to the loss of sex hormones but this increase in fibrosis was not a result of linear alterations in synthesis or degradation. In the RV, though, there was an increase in total collagen levels due to chronic pressure overload and independent of the loss of sex hormones. This increase in fibrosis was due to an increase in synthesis associated with increases in JNK activation and myofibroblast activation. Taken together, these results demonstrate differences in the regulation of ECM remodeling that occur in the LV, RV, and RCA in two swine models with relevance to HFpEF. This emphasizes the need to further explore the regulation of ECM remodeling at multiple levels of the heart in order to fully understand the pathogenesis of HFpEF.
Multivariate analyses of polygenic risk for impulsivity and alcohol use: a study of longitudinal trajectories of binge drinking in emerging adulthood
Authors:   , Miller Alex P.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] This dissertation aimed to extend previous genetic and neurobiological studies of the shared etiology of impulsive personality traits (IPTs), alcohol consumption and alcohol use disorder (AUD). The overarching goals were to (1) leverage advanced multivariate genome-wide association study (GWAS) approaches to improve current models of neurogenetic liability for IPTs using a dual-systems framework (e.g., top-down lack of self-control, and bottom-up sensation seeking and urgency), and (2) apply improved genetic liability models and polygenic scoring (PGS) techniques to the prediction of changes in binge drinking in developmentally relevant longitudinal samples. Study 1 included several structural, stratified, and genome-wide association analyses using epigenetic, transcriptomic, and neuroimaging datasets. Analyses and data were used to construct and investigate converging and discriminating evidence of dual-systems IPT genetic factor models and shared neurogenetic architecture with alcohol consumption and AUD. GWAS summary statistics generated in Study 1 were utilized in Study 2 to construct dual-systems IPT, alcohol consumption, and AUD PGS variables, which were then specified as predictors in longitudinal analyses of binge drinking progression in three independent longitudinal samples spanning adolescence to early adulthood. Results from Study 1 suggested distinct genetic architecture across tested dual-systems and alcohol use traits, though also indicated robust evidence of a neurobiologically defined shared genetic basis between sensation seeking and alcohol consumption. Study 2 results highlighted important associations between sensation seeking and alcohol consumption PGSs and trajectories of binge drinking across time and samples. In aggregate, these results represent novel findings regarding the genetic architecture of dual-systems IPT constructs and increase understanding of their relevance to alcohol use phenotypes.
Evaluation of calcium handling and dwarf open reading frame AAV gene therapy in Duchenne muscular dystrophy
Authors:   , Morales Emily D.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disease. Increased concentrations of cytosolic calcium in dystrophic muscle cells has been implicated in DMD pathogenesis. In healthy muscle, calcium from within the sarcoplasmic reticulum (SR) is released to the cytosol to initiate muscle contraction and is returned to the SR by the sarcoendoplasmic reticulum calcium ATPase (SERCA) during relaxation. In DMD, SR calcium release is elevated, while calcium uptake by SERCA is reduced. Strategies that improve SERCA function hold promise to reduce cytosolic calcium levels and treat DMD. In the present work, we explored the role of a small peptide SERCA enhancer, dwarf open reading frame (DWORF), in dystrophic muscle. We found DWORF was significantly reduced in the heart and diaphragm of the mdx mouse model of DMD. Following this discovery, we delivered 6 x 1012 vg particles/mouse of an AAV9.DWORF vector to 6-week-old mdx mice by tail vein injection. Because SERCA over-activation has been reported to reduce muscle function, we also injected wild-type (WT) mice, whose DWORF levels are already significantly higher than in mdx mice. We found that AAV DWORF gene therapy (1) improved SERCA uptake, heart function, and fibrosis in mdx hearts, (2) reduced SERCA uptake, worsened heart function, and induced expression of the SERCA inhibitor sarcolipin in WT hearts, and (3) did not improve muscle force production but slowed maximum rates of contraction and relaxation in mdx diaphragm. Additionally, we assessed the transcript levels of several calcium handling proteins in the canine model of DMD. We found transcriptional differences between normal and dystrophic muscles and between male and female muscles. Our findings are the first to show DWORF downregulation plays a role in SERCA dysfunction in dystrophic muscle and that AAV DWORF gene therapy is a promising technique to treat DMD, especially DMD cardiomyopathy. Our findings also highlight the importance of considering animal age and sex in dystrophic canine studies.
Tracing cat domestication through population genetics and capturing genotype-by environment interactions in US beef cattle genomic predictions
Authors:   , Nilson Sara Michelle
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Cat domestication initiated as a symbiotic relationship between wildcats and the peoples of developing agrarian societies in the Fertile Crescent. To refine the sites of cat domestication, over 1,000 random-bred cats of primarily Eurasian descent were genotyped. The overall cat population structure suggested a single worldwide population with significant isolation by distance of peripheral subpopulations with decreased heterozygosity as genetic distance from the proposed cat progenitor's (F.s. lybica) natural habitat increased. Domestic cat origins are focused in the eastern Mediterranean Basin, spreading to nearby islands, down the Levantine coast and into the Nile Valley. Climate change is driving the need for incorporating genotype-by-environment interactions in beef cattle genomic prediction models as animals frequently re-rank across environments. For United States Gelbvieh and Red Angus beef cattle, genotype-by-environmental inclusive models were compared to the current national genomic evaluation. Genotype-by-environment effects contributed [approx] 3 percent-11 percent of the phenotypic variation to growth traits. Maternal and direct genotype-by-environment effects varied across growth traits. With slightly higher accuracies, the current national genomic evaluation models tend to outperform the genotype-by-environment models.
Influence of nutrition and health behaviors on academic performance of students at a public Midwestern university
Authors:   , Ramdial Joel
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] This mixed-methods, grounded theory study investigated the relationship between health behaviors and academic performance among university students. The survey instrument collected data related to academic performance, demographic information, and health-related behaviors. 5 validated scales related to healthy eating habits, food security, physical activity levels, alcohol consumption, and sleep quality were included in the survey. 561 participants completed the survey, 20 survey participants were interviewed, and 5 participated in respondent validation interviews. Quantitative data analyses revealed diet quality and food security were significant positive correlates with academic performance, while body mass index was a significant negative correlate. Food secure students were found to have significantly higher grade point averages than students who were food insecure. Extant literature, survey data, and interview data were used to develop a substantive theory that proposed an explanation of how health behaviors influence academic performance. Following respondent validation interviews, a final grounded theory emerged. In the final model, access to food and stress were determined to be independent variables and nutrition, exercise, sleep, and alcohol were found to be mediating variables that may influence academic performance.
Hormonal and genetic control of leaf and vein development in maize
Authors:   , Robil Jan Lorie
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Grasses (Poaceae) have successfully colonized diverse terrestrial ecosystems and impacted human civilization by producing the bulk of world food supply. The grass leaf is distinct for having a sheathing base and strap-like blade -- an evolutionary modification from the petioled leaf of eudicots. A further innovation in the grass leaf is the venation pattern composed of parallel longitudinal veins (long veins) interlinked by transverse veins. The long veins are formed as the leaf grows wide early in the development. The small indolic plant hormone, auxin, controls leaf and vein development in plants. However, how it controls leaf and vein development in grasses is not wellunderstood. In Chapter 1, I review the literature on leaf vein development and highlight the knowledge gap on the role of auxin in the regulation of vein formation in grasses. In Chapters 2 and 3, I address two important aspects of grass leaf and vein research using Zea mays as the model system: 1) to develop a tool that will enable high-throughput analysis of vein number and morphology; and 2) to investigate the roles of auxin and two other plant growth hormones, gibberellic acid (GA) and cytokinin (CK), in regulating the leaf width and long vein number in grasses. Through collaboration, I helped develop the first image analysis framework dedicated for the parallel venation in grasses which can quantify vein traits and detect vein patterning defects. In Chapter 2, I describe the first detailed spatial-temporal map of auxin, CK, and GA during early leaf development in a grass species. I propose a conceptual model for hormonal regulation of medial-lateral growth and vein proliferation. This model can be used to develop testable predictions about hormonal regulation of leaf phenotypes altered by mutation or environmental response in maize and other grass species. Finally, in Chapter 4, I offer future perspectives about decoupling leaf growth and vein formation by focusing on spatialtemporal auxin response, which will be important for the targeted improvement of vein density to increase productivity in grass crops. Therefore, this thesis contributes technical innovations, advances the understanding of plant development, and provides new insights for future work.
Using ecological momentary assessment to identify risk factors for simultaneous alcohol and cannabis use
Authors:   , Wycoff Andrea M.
Published: February 2023

[EMBARGOED UNTIL 8/1/2023] Using alcohol and cannabis simultaneously, such that their effects overlap, is prevalent among individuals who drink alcohol and is associated with greater negative consequences than use of either substance alone. Understanding the factors that contribute to and maintain simultaneous versus single-substance use may shed light on reinforcement processes and intervention targets for this pattern of use. We used ecological momentary assessment to examine these processes in individuals' daily lives. The study had three aims: 1) test whether baseline motives for simultaneous use moderated daily-life associations between affect and simultaneous use, 2) test whether momentary motives for using alcohol or cannabis differed depending on whether individuals were simultaneously using the other substance, and 3) test whether simultaneous use moments were associated with greater affectively reinforcing outcomes compared to single-substance use. After completing baseline measures of motives for alcohol, cannabis, and simultaneous use, participants (N = 88, mean age 25.22, 60.2 percent female) reported 6+ times daily for 14 days on alcohol and cannabis use, affect, momentary motives for use, and subjective appraisals of use. Multilevel models were used to test each aim. Results from aim 1 include that baseline motives for simultaneous use did not moderate affect-use associations in daily life. Results from aim 2 demonstrated that social, conformity, and expansion motives were endorsed more strongly during simultaneous- compared to single-substance use moments. Results from aim 3 include that simultaneously using cannabis during alcohol-use moments attenuated the positive association between momentary anxiety-coping drinking motives and subjective drinking-contingent relief but also attenuated the increase in negative affect that accompanied coping-motivated drinking. In addition, simultaneously using cannabis during alcohol-use moments attenuated the positive association between enhancement drinking motives and subjective drinking-contingent pleasure despite no attenuation of the increase in positive affect that accompanied enhancement-motivated drinking. Collectively, this study furthers our understanding of the experiences that individuals are hoping to achieve by using alcohol and cannabis simultaneously and highlights ways in which this pattern of substance use may be reinforced.