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\u3ci\u3eIn vitro\u3c/i\u3e Investigation of Macrophage Functional and Metabolic Modulation
No full textMacrophages are a subset of immune cells with a variety of functions that are abundant in numerous tumor types such as colorectal and breast cancer. It has been suggested that macrophages may serve an important function as immune mediators in tumor behavior; however, macrophage activity is complex and remains not completely understood. The overall goal of this dissertation was to explore and exploit tumor-associated macrophage phagocytic function and the changes in their interactions with cancer cells in an in vitro mouse model and in 2D and 3D in vitro culture models. First, we wanted to better understand macrophage behavior under the various polarization states through longitudinal monitoring of metabolic and phagocytic effects of a murine macrophage cell line after exposure to various cytokine stimuli. Overall, the results of these studies indicate that autofluorescence imaging of endogenous metabolic cofactors can be a reliable method for monitoring the temporal and spatial dynamics of macrophage metabolism as they undergo activation after stimulation with cytokines as well as performing functions such as phagocytosis. Next, we created a 3D in vitro culture model that accurately resembled a 3D solid tumor while creating a novel analysis method to evaluate changes in multicellular spheroid structure and metabolism across spheroid micro-regions. Overall, the results of this study show that 3D multicellular spheroid models can provide a reliable solution for studying tumor biology, allowing for the evaluation of discrete changes across all spheroid microregions. Finally, we used the multicellular spheroid model as a preclinical model to test the effects of various therapeutic regimens (chemotherapy, immune checkpoint inhibitors, and phagocytosis checkpoints) to increase clinical understanding of combined regimens to off-set the side effects of traditional chemotherapy while stimulating immunogenic cell death. Results show that the combination of two immune checkpoint inhibitors in addition to a chemotherapy agent reduced spheroid growth (~46%), and reduced M2 macrophage expression and cellular proliferation while modulating cellular metabolism, ICD hallmarks, and phagocytic function. Overall, this study not only quantified microregional metabolic and structural changes in a simulated spheroid model but also quantified changes in ICD hallmarks and macrophage functional behavior. It was also found that relationships between spheroid structure and ICD hallmarks could exist after exposure to the combinatory regimen of immune checkpoint inhibitors and an ICD inducer
Quantifying the Role of Climate on Tropical River Flow (Guarare River) along the Panama Pacific Coast, 1981 – 2020.
Full text linkThe Guarare River watershed on the Azuero Peninsula of Panama, part of the Panamanian Dry Arc, experiences significant hydrological variability driven by seasonal changes, elevation, and the El Niño/Southern Oscillation (ENSO). This study investigates precipitation and river discharge patterns over 40 years (1981 – 2020), showing that elevation influences rainfall distribution, with higher-altitude areas receiving more precipitation during the Neutral and El Niño phases. In contrast, La Niña phases bring increased rainfall to lower-elevation areas, such as Pocrí. Seasonal ENSO effects reveal that El Niño phases reduce dry-season precipitation, lowering river discharge. La Niña events sustain high wet-season rainfall, peaking river discharge at 60 m3/s. Strong correlations during the La Niña and Neutral phases highlight the direct influence of precipitation on river flow. In contrast, El Niño phases suggest a reliance on groundwater for maintaining discharge. These findings demonstrate that the variable impact of ENSO phases, along with elevation and seasons, causes both drought and flood risks in the Guarare River watershed. The analysis underscores the need for adaptive water management strategies that account for ENSO-driven shifts, emphasizing groundwater as a critical factor in maintaining discharge during El Nino-related droughts and identifying specific areas vulnerable to flooding during intensified La Nina events
Exploring the Relationship Between Technical College Faculty Members’ Length of Teaching Experience and Their Moral Identity
Full text linkThis study investigates the relationship between faculty members’ length of teaching experience and their moral identity at a technical college in the Southeastern United States. Utilizing a quantitative approach, the research aims to determine whether a significant correlation exists between an instructor’s tenure in postsecondary education and their moral identity, as measured by the Moral Identity Questionnaire (MIQ). Additionally, the study examines the potential moderating effect of gender on this relationship. Data will be collected through a Qualtrics electronic survey distributed to all faculty members at the college, ensuring anonymity and minimizing survey errors. The survey includes demographic questions and the MIQ, which assesses moral identity through two subscales: Moral Self and Moral Integrity. Multiple regression analysis will be employed to analyze the data, controlling for age and gender to avoid confounding variables. The findings of this study are expected to provide valuable insights for educational institutions aiming to enhance their hiring and retention strategies by understanding the factors that influence moral identity among faculty members. By fostering a prosocial and ethical teaching environment, colleges can improve student outcomes and institutional reputation. The study also contributes to broader discussions on the role of gender in shaping professional identities and behaviors in educational settings
Elucidating the Mechanisms of Collagenase H from \u3ci\u3eHathewaya (Clostridium) histolytica\u3c/i\u3e in Collagen Degradation and Developing a Cross-linked Platform for Efficient Capture and Release of Adeno-Associated Virus Serotype 2 (AAV2)
No full textIn biological systems, Hathewaya (Clostridium) histolytica secretes collagenases that degrade structural collagen in host tissues and cause tissue necrosis. Despite their detrimental effects, these enzymes have significant therapeutic potential by effectively digesting various collagen subtypes to treat connective tissue disorders. The bacterium produces two homologous collagenases, ColG and ColH, with a catalytic module crucial for hydrolyzing collagen and binding domains, including collagen-binding domains (CBDs) and polycystic kidney disease-like domains (PKDs), for substrate interaction.
Although the crystal structure of the catalytic module of collagenase G (ColG) has been determined, shedding light on its chew-and-digest mechanism, the structure of collagenase H (ColH) remains unknown, limiting a deeper understanding of its catalytic mechanism. In this study, the structure of the ColH catalytic module was resolved in an unprecedented “closed” conformation using X-ray crystallography. Heteronuclear Single Quantum Coherence (HSQC) Nuclear Magnetic Resonance (NMR) spectroscopy further elucidated how ColH recognizes and unwinds collagen triple helix for endopeptidase activity. Small-angle X-ray scattering (SAXS) demonstrated how ColH binds to mini-collagen to feed the catalytic module with the substrate for digestion. Together, these findings provide a comprehensive understanding of ColH’s role in collagen degradation, which would help develop more effective therapeutic agents.
Also, a heparin-crosslinked membrane platform was developed for the large-scale purification of viral vectors. This platform can capture adeno-associated virus serotype 2 (AAV2) particles and release them on demand, which could be helpful for gene therapy applications
Creating a Sense of Home: Hispanic Students at Hispanic-Serving Institutions
Full text linkHispanic-Serving Institutions (HSIs) provide critical access to higher education for Hispanic students, yet their designation is based on enrollment rather than active support for student success. The purpose of the study was to describe and explore the sense of belonging for Hispanic students at a select Hispanic Serving Institution (HSI) with a high percentage of Hispanic students. Using photo voice, document analysis, and semi-structured interviews, the study identifies five key themes: (1) agency in belonging, (2) club participation, (3) fostering a sense of value, (4) institution and institutional agents, and (5) scholarship and funding. Findings underscore the need for HSIs to move beyond demographic designation and intentionally foster environments where students can create their own sense of belonging. Implications include strategic policy development, faculty engagement, and resource allocation to enhance Hispanic student success. Future research should explore belonging at institutions with lower Hispanic enrollment, the role of student agency in belonging, and how HSIs can better serve their evolving student populations
Gender Craze: Framing Policy Discrimination Against Transgender Students in K-12 Education
Full text linkTransgender youth in K-12 public education have been systematically marginalized through state-sanctioned violence and discriminatory policies, often portrayed as societal boogeymen. They face exclusion and othering due to restrictive state legislation, such as bathroom bans, sports participation restrictions, and limited access to gender-affirming care. Current research lacks a comprehensive analysis of how state-level legislation affects transgender students. This study addresses that gap by employing qualitative thematic coding to examine the language, framing, and impact of state education policies on transgender students. By analyzing how these policies are framed around themes such as protecting family, safeguarding children, individual liberty, constitutional rights, family rights, and freedom of religion, this research aims to reveal how such framing exacerbates the marginalization and othering of transgender students in public schools. The findings are to inform future policy reforms and advocacy efforts, emphasizing the urgent need for more inclusive policies that protect transgender students from discrimination and violence in public education
Evaluating the Impact of Work-Based Learning on Postsecondary Completion and Job Placement of Electronics Technology Students
Full text linkThe manufacturing industry today is facing a critical shortage in the availability of talent and skills needed in an ever-changing technological workforce. With an estimated 2.1 million jobs in the manufacturing industry predicted to be unfilled by 2030, organizations are struggling to find a workforce with the skills needed for this evolving industry (NAM, 2020; Ahmad, 2019). Employers have often suggested there is a lack of alignment between classroom experience in higher education, and work-based learning (WBL) is one option to bridge this gap (Krishnamoorthy & Keating, 2021). WBL provides real world experiences that connect learning in the classroom (Krishnamoorthy & Keating, 2021; Arthur-Mensah, 2017).
The purpose of this research study was to explore the relationship between work-based learning (WBL) participation and postsecondary credential attainment, time to complete postsecondary credentials and job placement in the electronics technology workforce. WBL encompasses multiple types of experiences that provide opportunities to connect classroom instruction with real-world application (Krishnamoorthy & Keating, 2021; Arthur-Mensah, 2017). This study focused on apprenticeships and internships as the types of WBL in an electronics technology field of study.
The research study utilized a quantitative, correlational research approach with a sample population from a regional comprehensive university. Participants were sked to complete a survey. Analysis of the data found that no significant relationship existed between participation in WBL experiences and completion of postsecondary credentials, time to complete postsecondary credentials and job attainment in the electronics technology field. Keywords: Work-based learning, Electronics technology, Credential attainmen
The Rhetorical Use of the Lower Classes in Three Primary Accounts of the First Crusade
Full text linkThis study analyzes the rhetorical use of the lower classes in three primary accounts of the First Crusade: Albert of Aachen, the Gesta Francorum, and Raymond of Aguilers — specifically with an eye towards the proper maintenance of the order of society through everyone performing their assigned role. Through a close reading of these three texts this study demonstrates how the three authors engage with and uphold versions of the idealized three orders model of medieval society. Though there is nuance between each source, broadly, each of the authors presents the lower classes as a force that needs to be guided by the clergy and controlled by the nobility. When the three orders model is upheld, society functions smoothly to the benefit of all, including the lower classes themselves
Influence of Smartphone Notifications on Behavior and Eye Movement Parameters of Emotional Attention
Full text linkThis study examined how smartphone notifications interact with emotional facial expressions to influence behavioral and physiological eye movement parameters of attentional orientation. Using a dot-probe paradigm, participants viewed mixed emotional face pairs (angry, happy, or neutral) following an auditory stimulus (smartphone notifications, control tones, or silence). Angry faces elicited greater behavioral accuracy and delayed initial fixations, consistent with heightened threat-related attentional engagement. Notifications disrupted attentional stability, reflected in increased fixations and pupil size variability. The combined effect of smartphone notifications preceding angry faces intensified attentional modulation—evidenced by slower responses, increased blinking, greater pupil constriction, less pupil variability, and faster initial saccadic orienting. These effects were moderated by individual differences: greater smartphone use—both self-reported and objectively measured—was associated with enhanced sensitivity and avoidance to angry faces, reflected in increased accuracy, larger pupil responses, and reductions in fixations and blinks. Elevated stress and anxiety predicted context-dependent attentional shifts, particularly under threat, with pronounced effects on pupillary and saccadic responses. Lower regulatory control was linked to greater distractibility, impaired performance, and faster threat-oriented saccades, whereas higher attentional control predicted more flexible and adaptive responses. These findings elucidate how smartphone alerts and emotionally salient stimuli interact with trait-level factors to shape attentional processes, highlighting the value of eye-tracking for disentangling cognitive-affective mechanisms in technology-rich environments
Koszul Cohomology of Canonical Products
Full text linkIn this thesis, we give a complete classification of the Koszul cohomology groups Kp,1(C, B, ωC ⊗ B) on a smooth curve C of genus g ≥ 2 with B p-very ample. Such a classification in the case B = ωC has been incomplete until [5]. The classification follows easily from our main result which precisely calculates Kp,1(C, B, B ωC ⊗ B) in terms of h0(C, B). This result also handles the case B = ωC. A straightforward application of Koszul duality yields a corollary to the main result which completely classifies the Koszul groups Kp,1(C, ω2C) for arbitrary C.
In [6] it was proven that for a line bundle L of sufficiently large degree, Kp,1(C, L) ≠ 0 if and only if p ∈ [1, r(L) − gon C]. The other rows of the Betti diagram are straightforward to calculate when L is nonspecial. The primary technique there re-packaged some of the main arguments of [32] which essentially allow one to trade Koszul vanishing for vanishing of sheaf cohomology of secant bundles on symmetric products Cp. The authors then conjectured that a lower bound guaranteeing this biconditional is linear in g. This was confirmed in [28] where the bound deg L ≥ 4g − 3 was constructed. The technique there involves resolving the kernel of a certain short exact sequence and showing cohomology vanishing by pulling back along the quotient morphism q : Cp → Cp. We show that this argument is essentially repeatable by instead pulling back along σ : Cp × C → C where Cp × C is thought of as the universal divisor associated to the Hilbert scheme C parameterizing the effective divisors of C of degree p + 1. This method proves to be slightly more optimal as it effectively lowers the earlier bound to 4g − 4