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Language Orientations, Emergent Bilinguals, and Schools: How School Leaders Position the Educational Experience for Emergent Bilinguals.
No full textDue to the formal positions of leadership in their school communities, the actions of principals and other school leaders impact the educational experience of their students. However, as a result of many school leaders’ lack of formal knowledge about Emergent Bilinguals (EBLs), bilingual education, and the role of the heritage language (HL) in children’s education and development, many school leaders negatively impact the support for EBLs and HLs in their schools and can inadvertently harm the long-term academic development of their students. This qualitative research study investigates how school leaders work for emergent bilingual (EBL) students in elementary schools in Pennsylvania. In this study, I used an instrumental multisite case study approach and conducted research across three elementary schools. I triangulated data from semi-structured interviews, document analysis, and field observations. The data provided insight as to how school leaders leverage foundational heuristics of language orientations and the purposes of education to position the educational experience of EBL students. This study helps researchers and practicing school leaders to understand how these seminal educational theories combine and shape the work of school leaders and the educational experience of EBL students in public elementary schools. </p
Story Circles: Building Community through Dialogue among K-12 Educators, Parent-Guardians and Members of the Trans Community
No full text{"value":"AbstractCisnormativity remains deeply embedded in educational institutions, normalizing injustice, making it acceptable for trans children to experience violence, abuse and isolation in schools and ultimately contributing to school drop-out. Changing cisnormative school cultures requires critical self-reflection, dialogue across differences and a collaborative approach to dismantling systems of oppression. In this study, 19 adults of various genders participated in 2 days of story circles, interactive theater and visioning exercises designed by the researcher in collaboration with three co-facilitators also of various genders. This research utilized a qualitative approach to a single bounded case study to explore how story circles might encourage empathy, understanding, and community building among K-12 educators, parents-guardians of trans children, and members of the trans community toward creating more supportive K-12 learning environments for trans and gender nonconforming students. Research questions were designed to reflect the three processes of change within Harro’s (2018) Cycle of Liberation—intrapersonal, interpersonal and systemic. To address the research questions, I analyzed data gathered from researcher fieldnotes of the story circles, semi-structured interviews of the 18 story circle participants (19 minus myself, the researcher participant-observer), audio recordings of circle check-ins, photos of the visioning board and researcher reflections. The qualitative analyses indicated that story circles and interactive theater built empathy, understanding and hope among participants; allowed participants to examine systems of oppression and explore potential solutions; and provided a launch pad for envisioning more welcoming and equitable school environments.
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Trends in Clinical Trial Participant Gender, Race, Ethnicity, and Age From 2018-2023 Across Various Therapeutic Areas.
No full textClinical trials are essential to the advancement of medical knowledge and healthcare advancements. However, persistent disparities in clinical trial participant representation have raised ethical concerns about equity, generalizability, and access to the benefits of clinical research. This thesis aims to retrospectively examine trends of clinical trial participant gender, race, ethnicity, and age from 2018 to 2023 across various therapeutic areas. Data was extracted from the FDA Center for Drug Evaluation and Research (CDER) Drug Trials Snapshots (DTS) database for 2018–2023. 230 clinical trials were submitted to the FDA for drug or medical device approval during the study period. Data visualization was conducted using the Tableau 2020.4 software program. In the 230 clinical trials, 166,117 individuals participated. Of those, 51.58% were female, 71.49% were White, 9.7% were Black, 10.17% were Asian, 14.69% were Hispanic, and 30.69% were over 65. During the study period, there was an increasing trend of female clinical trial participants. White clinical trial participants consistently account for the largest racial group, while Black, Asian, and Hispanic representation remained drastically lower. White and Asian participation increased over time while Black and Hispanic clinical trial participation decreased. Trends in clinical trial participants over 65 showed an upward trajectory throughout the study period. When analyzing the participant demographics on a therapeutic level, we did see an increase in some aspects of racial and ethnic diversity in oncology and neurologic and psychiatric disease clinical trials. Notably in neurologic and psychiatric diseases, we saw an increase in Asian, Black, and Hispanic clinical trial participation from 2022 to 2023. The study suggests that while we do see some more diversification in sex and age among clinical trial participants, more work needs to be done to improve racial and ethnic diversity. </p
Stochastic Methods for Multi-Level and Multi-Objective Optimization
No full textMulti-level optimization problems, with either single or multiple objectives at each level, have become instrumental in a variety of problems arising in machine learning, cybersecurity, and defense, including neural architecture search, continual learning, hyperparameter tuning, fairness, network interdiction, and power network defense. This thesis develops state-of-the-art stochastic methodologies and rigorous theoretical analyses to advance multi-level and multi-objective optimization in innovative directions. While stochastic gradient methods are well studied for single-level problems, recent advances have focused on bilevel or single-level multi-objective problems. However, many real-world applications involve conflicting objectives across multiple levels; scenarios that remain largely unexplored from a stochastic approximation perspective. This thesis bridges this gap by extending the algorithmic framework and convergence analysis beyond classical stochastic gradient methods. We explore several complex stochastic problems, including constrained bilevel optimization, bilevel problems with multiple objectives at one or more levels, as well as trilevel optimization.</p
Navigating Multisector Dynamics: Challenges and Solutions in the Regional Food-Energy-Water Nexus
No full textThe food-energy-water (FEW) nexus is characterized by bidirectional interconnections, where each component influences and is influenced by the others. These interdependencies can lead to critical challenges, including food insecurity, unmet energy demand, and water scarcity. To address these complexities, this dissertation presents an integrated modeling framework that captures the natural processes, human systems’ operations and dynamic feedback mechanisms within the FEW nexus. This framework leverages agent-based modeling (ABM) approach to simulate the decision-making behaviors of individual agents, allowing for a more realistic representation of interactions among food, energy, and water sectors. By incorporating both human and physical system dynamics, the proposed approach provides deeper insights into resource management strategies under changing conditions. The first research topic examines how human decision-making influences capacity expansion planning in energy systems under climate change impacts. This is achieved by developing a two-way coupled model that integrates an ABM with a power dispatch model. The ABM represents power generation companies as individual agents with heterogeneous characteristics, capturing their decision-making processes and collective behavioral patterns. Additionally, this study explores how technological advancements and varying future energy demand projections shape agents\u27 investment and expansion decisions. The second research topic shifts focus to another critical challenge of the FEW nexus: water scarcity. This study enhances existing drought prediction tools to support long-term, large-scale drought mitigation planning. To achieve this, we developed a predictive model that leverages remote sensing data to forecast agricultural droughts 12 months in advance. The model\u27s performance was evaluated by comparing its predictions with widely used drought indicators, assessing drought extent, intensity, and stability. Finally, the third research topic combines the previous two topics and expands the scope of the FEW nexus analysis by incorporating energy, water and human system dynamics into an integrated modeling framework. Water plays a crucial role in both the energy and food sectors, serving as a cooling resource for natural gas power plants and as an irrigation source for farmers. By integrating a hydrological model with the ABM that represents both the energy and food sectors, we developed a three-way coupled framework that captures the bidirectional feedback among sectoral interdependencies of energy, water and human system under direct climate change and technology improvement scenarios. This study examines capacity expansion decisions in the energy sector and farmers’ irrigation decisions under different technology evolution policies and a climate stress test, incorporating projections for temperature and precipitation. In summary, this dissertation develops a cohesive framework to untangle the complexities of the FEW nexus under climate change and water constraints by explicitly modeling human decision-making and sectoral interactions.</p
Overcoming bacterial antibiotic resistance mechanism using Escherichia coli outer membrane vesicles for novel drug delivery
No full text{"value":"Novel methods to combat resistance mechanism of Gram-negative bacteria are limited by their inhibition or removal through the use of enzymes and active transport pumps in innate or acquired resistance. Antibiotic resistance has become a leading health care concern globally with domestic death reported by the United States Center for Disease Control and Prevention analyzed that approximately 35,000 deaths annually are caused by resistant bacterial infections. Since the discovery of the primary antibiotic classes, no recent discoveries have been made leading development to focus solely on derivatives of current solutions. Isolated Gram-negative bacteria have demonstrated the ability to enhance their resistance mechanism and acquire extensive antibiotic resistance over the entire therapeutic spectrum. Gram-negative bacteria such as Pseudomonas aeruginosa (P. aeruginosa) possess a dual membrane structure moderating transport across the cell wall and is capable of downregulating specific transport proteins to further limit antibiotic entry. Without entry, antibiotics are ineffective against bacteria therefore a new delivery method is required to improve antibiotic activity. Gram-negative bacteria release lipid nanoparticles, outer membrane vesicles (OMVs), during growth to transport material, release toxins, and communicate between species. The cross-membrane transporter OMVs, sourced from Escherichia coli (E. coli) strain JC8031, possess antibiotic loading capabilities facilitated by an active sonication loading technique. Imipenem encapsulated in OMVs, IMI-OMVs, demonstrated potential for a novel antibacterial agent to combat bacterial resistance as an innovative delivery method. E. coli strain JC8031 is a hypervesiculating mutant strain which produced high quantities of OMVs but has demonstrated toxicity in the presence of mammalian cells. E. coli Nissle 1917 (EcN) possesses the same capacity to produce OMVs while having a GRAS (generally regarded as safe) designation from the United States Food and Drug Administration (FDA) indicating its accepted biocompatibility. We propose the use of EcN OMVs as nanocarriers for antibiotics to traverse the Gram-negative bacteria membrane and increase the therapeutic effect against bacteria. In this study we focused on the culturing and characterization of EcN OMVs through purification procedures. The encapsulation efficiency of the active sonication loading technique was optimized and compared to E. coli JC8031 to determine imipenem, a transport protein dependent antibiotic, content. The bactericidal effectiveness of the imipenem loaded OMVs (IMI-OMVs) were studied by treating P. aeruginosa strain PAO1 with encapsulated imipenem, free imipenem, empty OMVs, and unencapsulated imipenem with empty OMVs. We observed that IMI-OMVs sourced from both E. coli strains effectively inhibited the growth of Gram-negative P. aeruginosa. IMI-OMVs demonstrated increased antibiotic activity compared to free antibiotics at the same concentration. EcN IMI-OMVs matched and improved upon the bactericidal effect of E. coli JC8031 while possessing non-toxic characteristics. These results demonstrated the potential of EcN OMVs as novel biocompatible drug delivery carriers to overcome antibiotic resistance.
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Exploring Interfacial Structure Near a Hydrophobic Surface: A Computational Study
No full textMolecular dynamics (MD) simulations were conducted to investigate the interactions at the interface between aqueous solutions and hydrophobic polytetrafluoroethylene (PTFE), filling significant knowledge gaps in the literature and providing novel insights into the atomic-level interactions of water with planar hydrophobic interfaces.First, force field parameters for Titanocene Dichloride (TD) and PTFE were developed to address gaps in TD research and to validate PTFE simulations against experimental data. Subsequently, the effects of salinity and temperature on water droplet wettability were investigated, showing that PTFE\u27s hydrophobicity increases with higher salinity and temperature. Observations revealed ion segregation away from the PTFE surface, offering crucial insights into disruptions in water structuring and changes in droplet spreading.
Lastly, a new interfacial system was designed to simulate interactions between saline and pure water slabs on both porous and non-porous PTFE membranes. This led to novel findings on vapor bridge formation, slab-induced bending, variations in pore contact angles, and ion segregation. Salinity was found to prolong vapor bridge persistence, delay coalescence, increase deformation, and result in higher ion concentrations within the porous region. These findings will deepen the understanding of water slab interactions with hydrophobic surfaces and help advance desalination and membrane technology.</p
Telehealth in Medicine: Use of Telemedicine and Quality of Care Among Telehealth Enrollees with Mental Illness Post COVID-19
No full textTelehealth in medicine is described as using digital technology to provide healthcare services, medical education, and other general health advantages by connecting with clients in remote locations. This study aimed to assess the provision of care for individuals undergoing treatment at specialised mental health facilities that primarily utilised telemedicine after the COVID-19 pandemic in comparison to facilities that placed greater emphasis on in-person treatments. This research surveyed 100 participants who used telehealth at one point before and after the COVID-19 pandemic. These participants include either health practitioners or those seeking medical intervention. The convenience sampling method, a non-probabilistic sampling method, was used to recruit participants for the study. Questionnaires were also used to gather the respondents.The participants were (49) 49% female and (51) 51% female. 57 (57%) of the participants claimed that in-patient care was used, while 43 (43%) of the participants claimed that telehealth was used more for therapy. Convenience 10 (10%) was the commonest reason why telehealth was used as opposed to in-patient care post-COVID-19. A larger percentage of respondents, 63 (63%), stated that telemedicine post-COVID-19 was associated with higher quality of care for patients. Telehealth in medicine is described as using digital technology to provide healthcare services, medical education, and other general health advantages by connecting with clients in remote locations. This study aimed to assess the provision of care for individuals undergoing treatment at specialised mental health facilities that primarily utilised telemedicine after the COVID-19 pandemic in comparison to facilities that placed greater emphasis on in-person treatments.
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Paradoxes of Toleration: The Ambiguities of Church and State in Colonial and Revolutionary Pennsylvania
No full textThis dissertation offers a reassessment of Pennsylvania\u27s place as a model for religious liberty from settlement up to the election of 1800. Through a careful examination of private papers, printed material, denominational minutes, and governmental records, this dissertation uncovers a more complicated picture of religious liberty in the commonwealth than previous studies have acknowledged. This dissertation shows that Penn\u27s vision for his colony created a confounding relationship between church and state rather than a bastion of religious freedom. The resulting confusion prevented any clear policy of religious toleration from emerging in the colony and led to chronic disagreement between settlers of various religious and ethnic stripes. Without a clear guiding picture of religious toleration, settlers drew from their own thoughts and interest to create competing iterations of religious rights. Rather than a mutually beneficial religious pluralism, this dissertation shows how distrust, deepening resentment, and religious rivalry grew out of the governing philosophy of Pennsylvania itself. Furthermore, this study highlights historical change, local circumstances, and contingency in the ways Pennsylvanians approached religious toleration. As the colony matured under the pressures of imperial politics, population growth, settler expansion, and the political crises of the American Revolution, Pennsylvanians adapted the ways they spoke about and implemented religious toleration, showing the concept to be more of a "flexible grammar" than a political right. The initial confusion surrounding principles of church and state and the subsequent adaptations of the same indicate that no single philosophy of religious toleration defined the commonwealth, complicating any arguments placing Pennsylvania as the model that other governments followed.</p
Watershed Explorers: Digital Gameful Learning Experience Gameplay Investigated with Immersive Virtual Reality within a Technology-enhanced Lifelong Learning Ecology
No full text{"value":"This dissertation comprises three cohesive manuscripts investigating immersive gameful learning in virtual reality (VR) and its implications for lifelong learning. Manuscript 1 introduces the Lifelong Learning Ecology (LLE) and Technology-enhanced Learning Ecology (TeLE) frameworks, exploring how technological advancements shape learning ecologies across formal, non-formal, and informal settings. It highlights connectivism as a 21st century learning theory and advocates gameful design principles to enhance immersive learning experiences. Manuscript 2 presents an efficacy study using desktop VR (dVR) to assess Watershed Explorers, a gameful learning experience for middle school students. Significant improvements in watershed literacy and environmental awareness are observed, highlighting the educational value and engagement of gameful VR.Manuscript 3 extends this research by comparing dVR and headset VR (hVR) versions of a more specific iteration of Watershed Explorers across diverse learning settings. It introduces the Technology-enhanced Lifelong Learning Ecology (TeLLE) framework, integrating self-determination theory and the cognitive affective model of immersive learning. This empirical study assesses engagement and motivation outcomes through multiple linear regression analyses modeled from the LLE, TeLE, and TeLLE conceptual frameworks.
Key empirical findings indicate that the choice between dVR and hVR devices does not significantly impact immersion or learning outcomes across a wide age range (8–90 years), since participants in both VR conditions, across formal, non-formal, and informal learning settings, reported high levels of immersion and presence. After including all variables of interest in this study, the six predictor variables of the TeLLE regression model accounted for 66% of the total outcome variance (R^2 = .659). Regression analyses demonstrate gameful design as the most valuable predictor of learning outcomes, surpassing immersive affordances like immersion and presence. These findings support the use of any VR device for immersive and gameful learning experiences throughout lifelong learning contexts.
Overall, the dissertation underscores the importance of gameful design and contextual factors in optimizing immersive learning environments across VR platforms and wide age groups. It provides empirical evidence supporting gameful VR technologies as effective tools for lifelong learning, emphasizing the role of learning design in enhancing educational outcomes.
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