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An Examination of Lysine Acetylation in the Context of Bacterial Metabolism, Translation, and Regulation of Gene Expression
No full textPost-translational modifications are a critical tool bacteria employ to survive the challenges of microbial life. Acetylation continues to gain more recognition as a modification of unique importance because the sources of acetylation – acetyl-phosphate and acetyl-coenzyme-A – are critical metabolites associated with central carbon metabolism, acetate overflow metabolism and acetate assimilation. This suggests that acetylation, indelibly coupled to metabolic flux, integrates metabolic sensing with any cellular process or pathway where an acetylation alters the function of a protein. Intuitively, this makes sense. Of course, a bacterial cell would coordinate any cellular process closely with the amount of energy available to ensure survival. In practice, demonstrating this connection often proves difficult because disrupting the production of the sources of acetylation can have subtle but wide-reaching implications for cellular physiology generating variables in experimentation that must be accounted for. In the present work, I investigated lysine acetyltransferase-dependent acetylation of LipA, acetyl-phosphate-dependent acetylation of the ribosome, and acetylation of the response regulator RcsB spanning bacterial metabolism, translation, and regulation of gene expression. I demonstrated that overexpression of E. coli lysine acetyltransferases YfiQ and YiaC increases the detected lipoylation signal of the 2-oxoacid dehydrogenase E2 subunits AceF and SucB. I revealed that previously observed changes in the distribution of ribosomal subunits in response to acetylation during growth in tryptone broth change dramatically with the changing metabolic strategies of E. coli grown in minimal media limited for phosphate or magnesium. Lastly, I demonstrated that RcsB acetylation decreases its DNA-binding affinity and revealed residues that are targets for acetylation in vitro
Reconceptualizing Christian Nationalism
No full textThis thesis sets out to critically engage with existing research on Christian nationalism. It argues that current research suffers from a methodological focus that is too broad, and theoretical grounding that is too imprecise, both of which prevent researchers from grasping the full scope and intent of Christian nationalism, as imagined by Christian nationalists themselves. Drawing on data collected from X accounts (formerly Twitter) of Christian nationalist users, Christian nationalist podcasts, and Christian nationalist books, it employs qualitative content analysis, mapped to Bourdieusian field theory to provide a structured approach for the understanding complex data involving multiple spheres of power, culture, and religion, and providing possible future research pathways
University Resilience: Examining the Relationship of Acute, Externally-Driven Crisis Events to University Enrollment and Financial Stability
No full textThis dissertation investigated the phenomenon of a significant, acute, externally-driven crisis event on university resilience at four-year, tuition-driven, public and private higher education institutions in the United States of America. The study primarily considered the resilience indicators of university undergraduate enrollment and financial stability through the crisis context of COVID-19. It is theorized that a perceived lack of reliability, flexibility, and pace to evolve that higher education exhibited during and shortly after COVID-19 is a sustained point of vulnerability to a field under increasing review from a range of stakeholders and points of financial and public pressure. The study contemplated if acute, externally-driven crisis events, such as COVID-19, actually lead to reduced undergraduate enrollment, decreased financial stability, and lower or expose a lack of resilience. An exploratory, theoretically-grounded, comparative case study research method was utilized. Primary data collection and analysis were semi-structured interviews with well-informed participants from financial, enrollment, and undergraduate academic advising functions at one public, four-year, tuition-driven institution and at one private, four-year, tuition-driven institution. The supplementary data collection included publicly available documents and internal communications to investigate administrative decision-making surrounding COVID-19 with a focus on enrollment and financial areas of impact. The comparative case analysis was conducted at both the cross-institutional level and the cross-functional unit level. The study design included the Duchek (2020) organizational resilience framework as its conceptual basis and resource dependence theory as its theoretical foundation. The study was time bounded by March 2020–June 2023. Implications and future research that stem from this study are relevant to researchers, administrators, practitioners, and those concerned with the role of higher education and resilient societies and organizations. Primary study contributions included the Resilience Thematic Paradigm, resilience institutional capabilities and capacities, and the Higher Education Resilience Framework
Chemically Installed Organic Metal Nucleation Inducers on Molecular Materials for Ultrathin Metal Electrodes
No full textMetal aggregation is a general challenge in deposition of ultrathin metal electrodes on the molecular materials in OLEDs and organic solar cells. Nucleation inducers attached to the thin-film material are effective means to address the aggregation issue. Nucleation inducers enable affixation of different functional groups, optimized to bind to a particular metal electrode, onto the surface. In this dissertation, chemical reactions are used to install organic Metal Nucleation Inducers (o-MNIs) on molecular materials. Surface modification has been applied to two categories of materials: heteroatom containing and non-heteroatom containing materials. Accordingly, o-MNIs are applied to the surface of pentacene and TPBi. In its most optimal demonstration, applying different inducers to the surface of pentacene decreases the sheet resistance of a deposited silver electrode significantly and shifts the percolation threshold thickness from 11 nm to 8 nm. The smooth, continuous, electrode generated at low thicknesses highlights the suppression of the Volmer-Weber growth mode, as observed by scanning electron microscopy. Effectiveness was lower on TPBi, a heteroatom containing molecular material, due to competing nucleation within the molecular material itself. As the second part of the dissertation, MADN, a non-heteroatom containing semiconductor, has been chosen to be tested as an ETL layer in an OLED stack to determine the compatibility of o-MNI with device applications. A 9 nm Ag electrode deposited on MADN treated surface displays 72% optical transmittance and sheet resistance of 8.7 Ω/sq. The close turn-on voltages and overall similarity in performance suggest utilization of o-MNI are compatible with OLED applications and the o-MNI seems to be a promising methodology
Investigating Host Factors in Coronavirus Assembly and Egress
No full textCoronavirus (CoV) structural proteins congregate at the ER-Golgi intermediate compartments (ERGIC) prior to virus budding into the organelle lumen. Subsequent trafficking and fusion of virus-containing, ERGIC-derived vesicles then release nascent viruses from infected cells. Our findings in this dissertation illuminate mechanisms by which CoV structural proteins coalesce at the virus assembly and budding sites. The cytoplasmic tails of all CoV spike (S) glycoproteins contain variants of a consensus KxKxx coatomer-binding motif. Host coatomer complexes facilitate retrograde trafficking of client cargo proteins via recognition of such motifs. Utilizing reverse genetics methodologies, we introduced variations in the S coatomer motif in a prototype mouse hepatitis coronavirus (MHV) model. Viruses with altered coatomer affinities were debilitated and rapidly acquired suppressor mutations. These variations had profound effects on S intracellular localization, and subsequent interaction with other viral structural proteins, yet particles were released from infected cells. Secreted viral particles with altered motifs had reduced specific infectivities, which could be traced to sub-optimal S protein incorporation into virions. Our findings point to precisely evolved affinities between CoV S and host coatomer complexes, such that the requisite levels of S proteins are trafficked to ERGIC, where they integrate with other viral proteins for efficient virion assembly. Findings from this work provide a better understanding of CoV S intracellular trafficking and highlight their previously underappreciated influence on particle assembly
Insights on the Cranial Anatomy and Osteohistology of Cyonosaurus
No full textThis study investigates the cranial anatomy and life history of the small-bodied gorgonopsian Cyonosaurus. Previous research on gorgonopsians has disproportionately focused on larger members of the clade, leaving smaller forms relatively understudied. This gap has led to several unresolved questions, the most pressing of which concerns gorgonopsian ontogeny. Specifically, it remains unclear whether small-bodied gorgonopsians represent genuinely diminutive adult individuals or juveniles of larger species. The specimen NHCC LB1087 presents an ideal opportunity to address this issue and gain new insights into the biology of small-bodied gorgonopsians. The first chapter focuses on cranial anatomy. Due to the specimen’s preservation, many taxonomically important features were obscured by surrounding rock. To overcome this, NHCC LB1087 was CT scanned and digitally segmented, revealing internal structures that are rarely preserved. These anatomical details supported its identification as Cyonosaurus sp. The second chapter employs paleohistology to assess the growth strategy and ontogenetic stage of NHCC LB1087. The results indicate that this specimen exhibits a growth pattern distinct from any other gorgonopsian sampled to date. These findings challenge current hypotheses about gorgonopsian biology and their extinction during the Permo-Triassic Mass Extinction
Capturing Diverse Adolescents’ Social Contexts: The Development of an Ethnic-Racial Microaffirmations Scale for Peer Interactions
No full textThe development of a strong and positive sense of ethnic-racial identity (ERI) has been identified as an asset for ethnically and racially marginalized adolescents. Peer interactions during the adolescent years can support ERI development. In particular, a subtle micro-level form of peer support—microaffirmations—may be protective for ERI processes. However, the field of microaffirmations is very small, and there is no scale that captures adolescents’ experiences of ethnic-racial microaffirmations from their peers. The current study developed an ethnic-racial peer microaffirmations scale based on extant literature and feedback from 4 focus groups with 22 sophomore high school students. Findings indicated that 5 themes emerged regarding the draft measure the students discussed during the focus groups: scale items were relatable, no experience with scenarios in scale items, more nuance is needed in scale items, consider additional components for the survey, and phrasing of scale items. Students’ suggestions across these themes were used to revise the measure, which is comprised of 11 items and 2 subscales. This scale will provide researchers with a novel and valuable tool for better understanding ethnic-racial peer microaffirmations in adolescents’ lives and how such experiences may impact ERI development more broadly
Vital Environs: Ecologies of Modernism and the Nature Tradition
No full textVital Environs: Ecologies of Modernism and the Nature Tradition is an investigation of late nineteenth and early twentieth century British literature that explores the space between the individual and the external world. The project begins by exploring the “mind-body problem,” which is a topic in philosophy that recognizes the difficulty in understanding how the mind emerges from physical matter. While this topic has been in discussion since at least Descartes, science is still making crucial discoveries that challenge our understanding of this connection. I argue that the environmental crisis we find ourselves in today is a mind-body problem of global proportions, as our understanding of the physical world is intertwined with the perceptions we have of ourselves as individuals and as a species. The texts discussed in this dissertation enter this space and invite us to ask questions about our own place within the world. I begin with authors in the Nature Tradition, a theme in literature defined by Roger Ebbatson in 1980 that includes authors like Thomas Hardy and D. H. Lawrence. Such authors understood humanity as contained within Nature, and they therefore saw Nature as an important source of knowledge for human improvement. From there, I move into the city, looking at Strange Meetings by Harold Monro and several short stories by Virginia Woolf. I argue that while Modernism has a complicated relationship with climate change, these Modernist authors show a renewed interest in conscious experience in the world and help us rethink our traditional sense of subject and object. Lastly, I explore literature set on the seaside, with Rebecca by Daphne du Maurier and Woolf’s To the Lighthouse and The Waves, which give greater insight into how literary environment can be more than a literary setting, as it is often interlaced with our sense of time, memory, and selfhood. This dissertation is a literary and cultural investigation taking from theorists like Graham Harman and Timothy Morton, who have recently opened greater dialogue about the role of art in understanding the environmental crisis. I argue that literature is an excellent space to explore the negotiation between the self and external world, and that it allows for conversations that fall outside the purview of the physical sciences. Living in a profoundly dynamic moment in British history, the authors included in this dissertation grapple with their place in a changing world—a feeling that has certainly only heightened in the twenty-first century. I argue that ultimately, we may feel more emotionally capable of responding to the environmental crisis if we encountered it through writing, imagination, experience, perspective, and art
Changing Lanes, Crossing Industry Lines from Higher Education to Business Leaders: A Narrative Inquiry to Understanding the Challenges Faced by Residence Life Professionals Who Had to Change Career Paths Due to the Covid-19 Pandemic
No full textThis narrative inquiry examined how higher education residence life and housing professionals navigated career transitions into business leadership roles following the COVID-19 pandemic. Using human capital theory as a framework, the study explored the transferable skills cultivated in residence life positions and how these skills supported adaptation across industries. Participants’ narratives illuminated motivations for transition, including job market volatility, compensation concerns, and work-life balance, while also highlighting challenges encountered in reskilling and navigating identity shifts outside of higher education. The findings reveal the enduring value of competencies such as leadership, crisis management, diversity and inclusion expertise, and operational strategy in shaping professional pathways. Ultimately, this study contributes to scholarship by reframing the role of campus-based professionals as leaders equipped with versatile toolkits that extend beyond higher education. The implications underscore the importance of translating professional jargon, enhancing professional development initiatives, and supporting career mobility for practitioners navigating uncertain labor markets
An Era of Science Denial due to Fake News from the Power of Social Media
Full text linkSocial media networks have become the primary source of information easily accessible and reaching millions across the world. However, not all content creators have the knowledge or expertise of sharing claims they belief and verify to be true. This issue has significantly misguided generations of people influencing behaviors, and beliefs creating negative effects. The following investigation explores false narratives and the impact it has on the public where science denial begins