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COMPUTATIONAL ANALYSES OF POLAR INTERMOLECULAR INTERACTIONS USING CLASSICAL AND MACHINE-LEARNING METHODS
No full textIntermolecular interactions dictate many physical and chemical properties of materials. Understanding how intermolecular interactions correspond to a material’s macroscopic properties is key to engineering new technologies such as improved battery technology and pharmaceutical agents. Since it is not always possible to experimentally monitor how molecules behave, computational tools allow for the simulation and analysis of these molecules from the atomic scale. Additionally, existing computational tools are not always appropriate for systems of interest due to strong intermolecular interactions, like the ionic fluids within batteries. In this work, I considered two projects; one to refine computational toolsets, and the second to apply existing tools. In the first project, I will use ab-initio methods, semi-empirical methods, and machine learning methods to study lithium polysulfide behavior. I found that a training dataset varied in both size and energetic stability is essential for training machine-learning chemical potentials. The second project will use the General Amber Force Field to simulate the initial nucleation of tunicamycin and deoxycholate micelle formation. I found there to be correlations between the tunicamycin to deoxycholate ratio with both the system order parameter and the interaction energy between water and the organic molecules. These findings will enable the development of more realistic battery fluid simulations and the identification of an maximum tunicamycin: deoxycholate ratio to remain soluble in water
The Functions of PAAN/MIF Nuclease and Inflammation Pathways in Alzheimer’s Disease Models Induced by Pathogenetic Tau Proteins
No full textParthanatos-associated apoptosis-inducing factor (AIF) nuclease (PAAN), also called macrophage migration inhibitor factor (MIF), is a kind of mitochondria-related protein that participates in the clip of genomic DNA in the nucleus and results in cell death. PAAN/MIF has nuclease activity but can be inhibited through the E22Q mutation in the Parkinson’s disease model. This research proves that the PAAN/MIF pathway also participates in the neurodegeneration of the Alzheimer's disease model, and the E22Q mutation also resists the neurodegenerative process in this situation. At the same time, the pathogenetic Tau-PFF can induce the inflammation pathways related to cGAS-STING and NF-κB. However, the PAANIB-1, also named C8-31, which can inhibit the nuclease function of the AIF-PAAN/MIF component, cannot reduce these inflammation pathways in astrocytes. Although the PAANIB-1 does not inhibit the inflammation process in astrocytes, it does not mean it still relieves the inflammation process in microglia and neurons in the central nerve system during the progress of Alzheimer’s disease
FROM UPRISING TO IMPASSE: UNRAVELING THE ASSAD REGIME’S STALEMATE IN IDLIB PROVINCE
Get PDFThe Syrian conflict, which began as a series of uprisings in 2011, has since evolved into a complex and protracted crisis, with Idlib Province emerging as a focal point of contention. This doctoral thesis delves into the intricate dynamics underlying the Assad regime’s enduring stalemate in Idlib, dissecting the evolution of the conflict from its inception to its current impasse. Drawing upon a comprehensive analysis of historical, political, and socio-economic factors, this research scrutinizes the Assad regime’s strategies and tactics in Idlib Province.
Furthermore, this thesis investigates the role of opposition forces and their evolving strategies in confronting the Assad regime’s authority in Idlib. It explores the diverse array of armed groups operating in the province, their ideological orientations, and their interactions with local communities. Moreover, it examines the plight of civilians trapped in the midst of violence, displacement, and deprivation, and the challenges faced by humanitarian organizations in delivering aid amidst insecurity and obstruction.
By synthesizing empirical data, qualitative analysis, and theoretical frameworks, this thesis aims to contribute to a deeper understanding of the complex dynamics shaping the Syrian conflict, particularly in the context of Idlib Province. It seeks to provide insights that can inform policy decisions, humanitarian interventions, and academic scholarship aimed at addressing the multifaceted challenges confronting the region
The Transformative Use of Technology to Teach
No full textAlthough teachers in Singapore, enabled by one-to-one learning, have access to and knowledge of technology tools, most struggle to transform how technology is used for instruction. Transformation refers to a fundamental shift in the way digital technology is used for instruction, which includes moving away from teacher-centred approaches towards higher-order learning and more student-centred and student-initiated learning that may not be possible without technology. A literature review revealed that extrinsic factors such as leadership support and peer influence, as well as intrinsic factors such as technology knowledge, self-efficacy and belief, were critical in influencing teachers' transformative use of technology to teach. A needs assessment involving 21 teachers based on a mixed-methods sequential explanatory approach was conducted. Findings showed that while low levels of knowledge and self-efficacy were largely responsible for teachers’ struggle to transform how they used technology for instruction, peer influence was crucial in helping teachers learn and adopt new approaches to teaching with technology. A 16-hour professional learning intervention over eight weeks was proposed in which teachers learned about new technologies, approaches, and associated pedagogies, documented concrete plans of action and reflected on their learning, designed a classroom activity and received feedback from a colleague who would observe their classroom teaching. To enable the school to adopt elements of the professional learning intervention as part of its regular and on-going professional learning programme, a mobile application (Pedagram) to help teachers conduct lesson observations as well as a video creation template to support teachers create a school-based repository of technology videos were developed. The overarching intent was to empower teachers to take control of their own professional learning
THE CONNECTION BETWEEN ACTIVE GALACTIC NUCLEI, INTERSTELLAR MEDIUM, AND EVOLUTION OF NEARBY GALAXIES
No full textThe continuous efforts of the scientific community have brought to light a panoramic view of galaxy evolution: galaxies grow by actively forming new stars out of gas accreted from the intergalactic medium or through mergers with other galaxies, which could also fuel black hole accretion at their centers. Feedback from stars and black holes regulates the growth of the galaxy and eventually halts its star formation. While this picture is supported by both observations and simulations, numerous details are still unclear. The gas accretion onto galaxies and the role of active galactic nuclei (AGN) are particularly intriguing. The interstellar medium (ISM) of galaxies contains a wealth of information as it is where the stars are born and physical mechanisms leave their imprints. In this thesis, I investigate the connection between energetic processes and the evolution of nearby galaxies using the ISM as a probe. By studying the metallicity of spatially resolved regions in star-forming galaxies, I find that their chemical composition could be explained by the mixing of metal-poor and metal-rich gas. This study provides strong evidence for gas accretion onto galaxies when direct observations of inflowing materials are difficult. Moving on to more evolved galaxies, I conduct a detailed case study on a post-starburst galaxy utilizing multi-wavelength data and find evidence for a multi-phase outflow and a weak, deeply buried AGN. I show that the outflow is unable to remove a significant amount of gas from the galaxy and star formation could be quenched by disturbing rather than removing the gas. This study supports the less violent picture of quenching in the nearby universe. Finally, I examine the ISM of nearby merging galaxies and hosts of different types of AGN using observations that trace different gas phases. I find that while nearby obscured AGN could emerge from galaxy mergers, they are unlikely the precursors of unobscured AGN, which might contain rich ISM in a different gas phase. This study offers a different perspective to the traditional explanation of different types of AGN and provides insights into necessary new data and future research directions
EXPLORING THE PROPERTIES OF THE DM TEST FOR EPIGENETIC SELECTION AND RECOVERING TIME-ORDERING OF SINUSOIDAL FUNCTIONS WITH VARYING PERIODICITIES
Get PDFThe work done in this project presents expansions on tools used to investigate biological phenomena. In the first part, we aim to understand the dM test, a test for epigenetic selection. We do this through a sensitivity analysis, which breaks down the features that impact the dM test results. We also find a biologically relevant negative control for the dM test. Finally, we look at the binding profile of transcription factors on promoters. This work expands on the knowledge of the dM test, including its sensitivity. This is very important, as the dM test is treading new ground in the field of evolutionary molecular biology. In the second part of the project, we try to generalize a method created to recover time-ordering of sinusoidal functions. We are able to successfully derive the principal components necessary to do this, and we create a pipeline which is able to generalize the process to functions that have different periodicities. Though this project doesn’t have any immediate applicability at the moment, this generalization helps us understand further the relationships between sinusoidal functions and principal component analysis. Additionally, related processes that can be modeled with differing sinusoidal functions exist in the natural world. Overall, even though these projects are not related, they expand on prior tools used to understand biological processes, and prove to have useful possible applications
Informatics Approaches to Enhance Natural Disaster Risk Mitigation for Community-Dwelling Older Adults
Get PDFProblem Statement
Natural disasters are increasing in frequency and strength due to climate change and pose challenges for health and human services providers when they must meet the needs of their populations in difficult conditions. Vulnerable populations face disproportionate risk in these events, and addressing their needs in natural disaster contexts is a matter of environmental justice. One such population is older adults, which have greater natural disaster-associated morbidity and mortality. Population health informatics approaches may help providers to meet the needs of vulnerable populations in these scenarios, but they have not been widely used for natural disaster use cases.
Methods
This dissertation explores how population health informatics approaches could mitigate the disproportionate natural disaster risk of community-dwelling older adults. The first manuscript uses document analysis to characterize risk factors for older adults in natural disasters and compares them to national vocabulary standards for information exchange to assess terminology readiness. Next, the second manuscript examines implementation considerations for such informatics approaches through interviews conducted with subject-matter experts. The third manuscript explores the current enabling factors and potential policy actions to further population health informatics approaches for this use.
Results
There are many opportunities to leverage population health approaches to mitigate older adult’s risk from natural disasters. While some improvement is needed to strengthen technical interoperability and infrastructure, most of the implementation challenges for this use are related to other factors.
Conclusions
These manuscripts serve as a compendium of tools to explore population health informatics approaches for natural disaster preparation and response. This body of work serves as a demonstration of a formative evaluation of a community-level population health informatics use case that was conducted in an academic setting. The methods used for this work could be applied to other use cases to address pressing public and population health needs that cross institutional boundaries in the rapidly-evolving community information sharing ecosystem
THE KESSLER CONDUNDRUM: ASSESSMENT OF THE EXTENT TO WHICH A BIFURCATED APPROACH TO GLOBAL REDUCTION OF KE-ASAT MISSILE TESTING WILL IMPROVE U.S. SPACE DOMINANCE
Get PDFThe space domain represents a critical component to the safeguarding of U.S. national and international security interests, most notably via the thousands of satellites that occupy the Earth’s orbit. These satellites remain responsible for crucial civilian and military functions, including navigation, communication networks, the verification of arms control treaty compliance, intelligence data, and more. Despite the critical role satellites play, space remains one of the most vulnerable military domains, lacking meaningful mechanisms to protect and repair itself. Though natural space objects pose a significant danger to satellites, today’s most pressing threat to satellite safety is man-made, orbital debris, most notably those derived from dangerous kinetic energy anti-satellite (KE-ASAT) missile testing. Despite the considerable number of orbital debris created by these tests and the increasing danger of orbital debris and orbital congestion, existing policy, and legal frameworks, including unilateral moratoriums and guidelines, existing arms control agreements, and proposed treaties, remain insufficient to curb state interests in continuing KE-ASAT testing. This defect in deterring KE-ASAT testing owes in large part from intense politicalization. The U.S. and Western world remain eager to maintain democratic status quo in the space domain, whereas adversaries, notably, Russia and China, are hesitant to allow U.S. to assert its dominance in yet another military domain. As such, this study seeks to look beyond existing frameworks, to argue that normative efforts alone are insufficient and must be coupled with a strong multilateral agreement that cures the ambiguity and enforcement defects that pervade modern space arms control agreements to hold states accountable for the orbital debris they create
CLOSING EQUITY GAPS IN IMMUNIZATION AND PRIMARY CARE SYSTEMS: UNDERSTANDING HOUSEHOLD, COMMUNITY, AND HEALTH SYSTEMS BARRIERS TO REACHING VACCINE-ZERO DOSE AND MULTI-ZERO DOSE CHILDREN IN AFRICAN COUNTRIES
No full textBackground: Reaching the 14 million zero dose (ZD) – or unvaccinated – children is a global priority, largely motivated by the assumption that ZD children are routinely missed by the health system. This work aims to 1) introduce the concept and indicator for ‘multi-zero dose’ (MZD) to identify children that have not received several primary care services, 2) quantify how sociodemographic and health systems factors influence ZD and MZD status in African countries, and 3) identify opportunities to strengthen a child’s first immunization contact in a high ZD context.
Methods: Using public data from 30 African countries, we introduced the MZD indicator and conducted statistical and geospatial analyses to describe the ZD and MZD populations. We developed a database of health systems and contextual indicators potentially influencing primary care, and used multilevel logistic regression modelling to estimate the influence of household, community, health systems, and contextual factors on ZD and MZD. Lastly, we conducted semi-structured interviews in Madagascar to understand barriers and opportunities to strengthen birth dose vaccination platforms.
Results: Our MZD indicator includes facility delivery, postnatal care, DTP vaccination, and vitamin A supplementation. Across 30 African countries, 20.6% of children 12 to 35 months are ZD and 10.0% are MZD. Half (50.2%) of ZD children are not MZD and have connection with the health system, but in 9 countries, fewer than 10% of ZD children are MZD. Children in conflict areas are approximately 3.5 and 2 times more likely to be MZD and ZD, respectively. Children in countries with higher climate risk are 7 (aOR=6.96, 95% CI: 1.61, 30.1) and 4 times (aOR=4.19, 95% CI: 3.03, 5.80) more likely to be MZD and ZD, respectively, when controlled for other factors. In Madagascar, health systems improvements can strengthen birth dose vaccination, including developing and disseminating a clear birth dose strategy, mitigating stockouts, addressing provider concerns over vaccine wastage, and compensating and strengthening the community agent system to support home births.
Conclusions: While half of ZD children have connection with the health system, focusing on ZD hotspots can reach MZD children. Routinely collected sub-national health systems data is needed to guide ZD and primary health care programs
Examining the Impact of Conservation-Oriented Dive Experiences on SCUBA Instructor Job Satisfaction and Job Retention in Southern Florida
Get PDFThis capstone investigates the impact of conservation-oriented dive experiences (CODEs) on SCUBA instructor job satisfaction and retention within Southern Florida's diving industry. The study aimed to determine whether instructors involved in teaching CODEs reported higher job satisfaction and retention rates compared to those teaching dive experiences not focused on marine conservation. Two hypotheses were tested: Hypothesis 1 (H1) posited that SCUBA diving instructors teaching CODEs would report higher levels of job satisfaction compared to instructors who do not, and Hypothesis 2 (H2) posited that instructors teaching CODEs would exhibit higher job retention rates compared to instructors who do not.
A survey was developed and administered to instructors in February-March 2024. A total of 93 instructors completed the survey. The data were analyzed using t-tests, backward regression analysis, importance/satisfaction matrix correlation, and word frequency tests.
Key findings indicate that both null hypotheses were accepted, suggesting no significant differences in satisfaction and retention rates in Southern Florida between instructors teaching CODEs and those who do not. However, backward regression analysis suggested that instructors who felt personally fulfilled by educating students about marine conservation tended to report higher overall satisfaction levels. A deeper examination of conservation motivations revealed that 86.4% of instructors anticipate higher long-term career satisfaction when involved in CODEs. This proposes a homogenous sample, with a majority indicating they were conservation-oriented. Because the majority of the sample had taught CODEs, this may have limited the ability to detect statistically significant differences in the t-tests.
This study represents the first of its kind, exploring instructors' conservation motivations in relation to job satisfaction and retention. The findings underscore shared conservation motivations among SCUBA instructors in the region and highlight the need to study these motivations further in the hopes of improving the industry