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ASSESSING THE CHINESE NAVAL INFRASTRUCTURE CHANGES IN THE SOUTH CHINA SEA USING GEOSPATIAL INTELLIGENCE
Get PDFThis capstone will present a collection, analysis, and reporting plan for assessing naval activities and presence in SCS. The project was made possible by obtaining data from Satellite imagery from Google Earth to identity, monitor & assess naval infrastructure. Geospatial intelligence has been used to identify naval activities in South China Sea (SCS) and their impact on the natural resources as well as the geopolitical aspect of the effects in the region concerning territorial claims. The Google Earth Imagery reveals that the Chinese have created and constructed large artificial Islands from dredging and land fill on which the new naval bases are situated. These bases are equipped with port facilities/infrastructure with long runways, aircraft hangars, watch towers, radar/comms facility and missile shelters. The Chinese built six artificial Islands at six different locations. Yet, some of these artificial islands have increased the likelihood of disputes with neighboring states in the SCS Region. Nearly all are well developed and some in disputed areas according to International Maritime laws. Open-Source intelligence is considered as an insightful source of reliable information with regards to the regional Maritime policies and laws. Most of these artificial islands were built and in operation before 2017, and part of the project will be to look for evidence of changes overtime
Unsupervised Structural MRI Harmonization by Learning Disentangled Representations
No full textMagnetic Resonance Imaging (MRI) is a noninvasive and flexible imaging modality commonly used to study the human brain. Its flexibility allows for multicontrast image acquisition within a single imaging session, providing comprehensive insights into various tissue properties and pathologies. However, this flexibility also introduces challenges in standardizing MR acquisition across different sites and scanners. This variability can cause undesired image contrast variations, which often leads to inconsistencies and inaccuracies in subsequent neuroimage analysis.
Current harmonization methods, while aiming to mitigate these issues, often struggle with limited generalizability and can inadvertently introduce anatomical inaccuracies---also known as anatomy hallucination. To address the issues posed by the inherent variability in MR acquisition, this thesis revisits the unique attributes of MRI and integrates them with advanced deep learning techniques for improved MRI harmonization.
This thesis offers three principal contributions that elevate the field of unsupervised MRI harmonization. First, we introduce CALAMITI, an approach that leverages the multicontrast nature of MRI to extract disentangled representations of anatomy and contrast, resulting in robust and precise multi-site harmonization. Second, we propose an improved disentangling framework for multi-site MR harmonization that operates effectively with single-contrast MR images. We also propose an evaluation metric for quantitatively measuring disentanglement. Third, we present, HACA3, a unified approach to various harmonization scenarios. HACA3 employs a novel attention mechanism to produce optimally harmonized images, taking into account anatomy, contrast, and artifact information from MR images. Through extensive testing on diverse MRI datasets, our research demonstrates the effectiveness of these methodologies, marking a step forward for reliable and consistent neuroimage analysis
Optimizing the Process of Opening Regional Sites: A Strategic Framework for Streamlined Expansion and Operational Efficiency
Get PDFEnhancing the development of opening studies in our region involves strategically optimizing processes to ensure smoother and more efficient operations.
This can be achieved by effectively and efficiently opening drug trials in our regional hospitals, focusing on reducing complexities and delays. One key area of improvement is minimizing the number of people involved in the opening process, which can lead to streamlined communication and faster decision-making. By developing a more streamlined workflow, we can not only expedite the initiation of studies but also improve overall operational efficiency, ultimately leading to better outcomes in our regional healthcare research
A Qualitative Approach To Understanding The Capacity To Operationalize A Culture Of Equity And Psychological Safety In A Federal Public Health Organizational Setting
Get PDFBackground: This thesis contributes to the robust body of literature on workplace culture, organizational justice, and the psychological wellbeing of employees as explored in the federal public health workforce. Through a multi-method qualitative analysis, the study examined the experiences and perceptions of the federal public health workforce for evidence of equity, organizational justice, and psychological safety. Findings suggest implications for informing the organizational design of federal agencies through an interoperable framework that combines culture drivers and organizational justice theory to create and sustain a culture of equity and reinforce psychological safety for all workplace members. Given the importance of employee psychological well-being to job performance, this study investigated the mediating role of leadership on sustaining a thriving workplace culture.
Methods: The data were gathered from current and former full-time federal employees working in public health between 2016 and 2023. A total of 111 responses were received across three data collection activities (82 surveys, 23 participants of 6 focus groups, and 6 individual interviews).
Results: Findings suggest that a culture of equity, organizational justice theory and psychological safety are important components of workplaces to the full-time federal public health workforce. Leadership was found to have the most significant qualitative impact on staff’s perception of psychological safety. While leadership was reported as primarily responsible for creating buy-in for the organization’s culture among study participants, existing research suggests all organization members have a role in sustaining a thriving culture driven by equity, justice, inclusion, and psychological safety.
Conclusion: This qualitative study found that members of the federal public health workforce desires a work environment where workplace mental health and well-being are essential and foundational to organizational operations. People serving in the federal public health workforce values respect, belonging, and fairness in the workplace and look to organizational policies, interpersonal interactions and the work setting options for evidence of equity. A better understanding of how to use a holistic workplace wellness conceptual model could help the federal public health workforce operationalize a culture of equity, prioritize psychological safety, and activate organizational justice in policies and practices
Designing the Hardware and Software of Synthetic Hydrogel Machines Using DNA Circuits, Transcription Networks and Machine Learning Guided Algorithms
No full textDeoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are fundamental molecules in biology, playing central roles in storing, transmitting, and expressing genetic information, as well as regulating various cellular processes essential for life. Additionally, DNA and RNA are also highly programmable molecules due to the specific base pairing interactions between their nucleotide building blocks, empowering researchers to engineer programmable materials and intricate synthetic circuits with precise control and specificity. In this thesis, I propose to leverage the programmability of DNA-based computing systems and provide blueprints to build soft robots using synthetic hydrogel materials and DNA. In Chapter 2 and 3, I investigated different designs of enzymatic DNA circuits, to develop the software of the synthetic robots. Through designing the computing elements with switchable transcription nodes and other regulatory elements, I created dynamic programs capable of specific behaviors such as signal propagation, oscillation, and multi- state stability. These programs may serve as the building blocks in designing functional modules to program synthetic robot behaviors. In Chapter 4 and 5, I investigated the designs for DNA-co- polymerized hydrogels, such materials could respond to different DNA signals, serving as an ideal target hardware for designing DNA-controlled synthetic robots. Through designing the sequences and actuation mechanics, I developed synthetic hydrogel materials capable of reversible size and shape change when different DNA and RNA signals are introduced. Finally, in Chapter 6, utilizing state-of-the-art machine learning models and a genetic algorithm, I developed a computational material design optimization software, that could guide the design and development of synthetic soft robots, to assist the design of complex metamorphic materials
A TRANSLATION COST DECISION AID TO ENABLE RESEARCHERS TO CONDUCT COMPLIANT CANCER CLINICAL TRIALS THROUGH THE INCLUSION OF PARTICIPANTS WHO PREFER A LANGUAGE OTHER THAN ENGLISH
Get PDFCancer affects all ages, races, and ethnicities worldwide, and cancer clinical trials offer opportunities for patients to access new and potentially groundbreaking drugs and therapeutics in the final testing stages. As of 2019, 22% of the population of the United States speaks a language other than English at home, an increase in population of 52.3% since the 2000 U.S. Census. Federal regulations and policies require the inclusion of diverse populations in federally sponsored research, including participants who prefer a language other than English (PLOE). To be compliant with federal regulations on Informed Consent of Human Subjects, studies must include informed consent documents understandable by all research participants. Cost may not be used as justification for excluding PLOE participants. Additionally, excluding PLOE participants can affect the generalizability of research results and violates the Belmont principle of Justice.
This study aims to show that current cancer clinical trials are non-compliant with federal requirements and to create a translation cost decision aid to provide researchers and research administrators with a tool for quick cost analysis of the translation of long-form consent documents to include a variety of language preferences in research studies. Utilizing localized data of language usage and cross-referencing with an average per word cost to translate into the top ten preferred languages, this tool will enable research administrators and investigators to find the best cost-per-participant rate and an estimated number of eligible participants to expand language inclusion with the long-form consent document
THE ROLE OF NRAMP TRANSPORTERS IN FE AND MN HOMEOSTASIS IN CANDIDA ALBICANS
Get PDFTrace metals, like Fe and Mn, are essential to both humans and pathogens. In nutritional
immunity, our body withholds metals from pathogens to starve them and protect us, while the
pathogens have developed different mechanisms to seek these essential metal nutrients. The
NRAMP family of divalent metal cotransporters is thought to be involved in this metal tug-of
war between hosts and pathogens. Candida albicans, a fungal pathogen that creates a large
public health burden by causing severe infections in immunocompromised populations, has four
NRAMP transporters including SMF3, a putative vacuolar Fe transporter, the SMF12 and
SMF13 Mn transporters and SMF11 of unknown function. Our previous preliminary studies
showed that smf11 mutants accumulate higher Mn and higher Fe; however, why both metals
would be increased, and the function of SMF11 was unknown.
In this thesis, we found that the Mn hyperaccumulation of smf11 mutants is a response to
the elevated Fe of these cells. In both smf11 mutants and WT cells, Mn levels will rise when
cells hyperaccumulate Fe. This Mn accumulation response to Fe occurs in an SMF12 and/or
SMF13 dependent manner. Fe hyperaccumulation is therefore the primary phenotype of deleting
SMF11. In investigating the function of SMF11, we found that smf11 mutants behave as other
Fe-sensing mutants, such as mrs4 encoding a mitochondrial Fe transporter, the ssq1 chaperone
for mitochondrial Fe-S cluster biosynthesis, and the fre1 ferric reductase; all these mutants are
under constant Fe starvation stress and constantly accumulate higher intracellular Fe
accumulation. Like Fe-sensing mutants, smf11 mutants show high ferric reductase gene
expression and higher ferric and cupric reductase activities. We also identified a new Fe
starvation marker: the reactive oxygen species (ROS) burst induced during cell hyphal
morphogenesis by FRE8, a NADPH oxidase in C. albicans. In smf11 and fre1 mutants, no FRE8
ii
ROS burst was induced during hyphal morphogenesis. As a result, we conclude that SMF11 is
involved in Fe homeostasis in C. albicans. The loss of SMF11, FRE1, or other Fe-sensing genes
will put cells under constant Fe starvation and result in defective virulence, making these
proteins potential drug targets for fungal infection
Improving the Academic Success of Nontraditional Students in Online Learning
No full textNontraditional students are the fastest growing student population in higher education, representing over 40% of the student body and the largest segment in online learning. A body of literature suggests that nontraditional students face greater challenges compared to their traditional counterparts. These challenges include balancing multiple responsibilities, adapting to online learning, and instructional design that is not compatible with their learning needs. Using an explanatory sequential mixed method design, this study investigated the challenges of nontraditional students in an online learning environment and the course design factors influencing their academic success. Quantitative data was collected using a 57-item survey, and qualitative data was obtained via virtual, semi-structured interviews. Seventy-three nontraditional students at a community college in Northern California participated in the survey. Of those, a purposive sample of six students with work and/or family responsibilities participated in the interviews. The findings of this study indicated that having work and family responsibilities was a major challenge, with the majority of the participants reporting feeling often overwhelmed juggling their multiple roles. Furthermore, students who had been absent from the academic environment for an extended period faced additional difficulty adapting to online learning and using technology. In addition, the significance of instructor support was greatly emphasized in both quantitative and qualitative data. In terms of course design, participants considered clear course structure and organization, relevance of learning to their professional contexts, and frequent opportunities for interaction to be important to them
EVALUATING REGULATORY FRAMEWORKS FOR INTERSTATE HYDROGEN PIPELINES
Get PDFDecarbonization of heavy industry with hydrogen will require transportation of hydrogen via interstate pipeline. The federal government currently exercises minimal regulation over these pipelines. Existing literature is focused on technical and economic feasibility of hydrogen pipelines and discussion of the regulation of these pipelines is limited. This paper seeks to determine if existing regulations could be effective in regulating a clean hydrogen pipeline network or if new regulations should be developed. A qualitative multi-criteria analysis is used to evaluate three existing regulatory framework options, focusing on siting, ratemaking, service, and export regulations. The analysis determines that none of these existing options adequately address hydrogen pipelines, and a new framework should be developed. Suggestions for a new framework are provided based on learnings from the conducted research and analysis
Testing Of 4-Hap Drug Analogs On Myosin Ii Bipolar Thick Filament Formation
No full textA cell’s ability to respond to mechanical stimuli, otherwise known as mechanoresponsiveness, has become an attractive target for therapeutics due to their consequential effects on growth and proliferation. Cancer cells have been shown to have distinct mechanical properties, which can be targeted with small molecule drugs. Our lab discovered that the small molecule 4-hydroxyacetophenone (4-HAP) modulates cell stiffness by increasing nonmuscle myosin IIC (NMIIC) and nonmuscle myosin IIB (NMIIB) bipolar thick filament (BTF) formation in human cells. However, its molecular mechanism of action remains unknown. Here, we aim to determine if the molecular analogues of 4-HAP also produce a change in the mechanical phenotype of cells. Using TIRF microscopy, we imaged myosin II bipolar filaments in Dictyostelium discoideum upon treatment with 4-HAP, 3-HAP, and 2-HAP at different doses. Images were analyzed for fluorescence intensity, and it was found preliminarily 2-HAP and 3-HAP treatment does produce a statistically significant effect on NMII BTF formation. However, for a given dose, it is not statistically different compared to 4-HAP. In addition to this, we tested the efficacy of acetophenone, a small molecule similar to 4-HAP but lacking a hydroxyl group. Preliminary results show acetophenone had no observable trend on NMII BTF formation, indicating the hydroxyl group is necessary for regulating NMII BTF formation. Finally, we discuss utilizing computational modeling to further understand the properties of contractile proteins in the cell cortex. The lab has have found that these contractile proteins (including myosin II, cortexillin I, IQGAP1, and IQGAP2) preassemble into macromolecular assembles which we have called Contractility Kits (CKs). In our lab, we have developed a computational model of CKs using SpringSaLaD to determine how CKs form. The model predicted IQGAP1/2 knockout mutants will form faster diffusing cortexillin I/myosin II CKs. The model also predicted IQGAP2 single mutants will have limited myosin II BTF assembly. To test these predictions, we have developed cell constructs for use in Fluorescence Cross Correlation Spectroscopy and other experiments. Better understanding of 4-HAP’s mechanism and downstream effects on contractile protein machinery will further guide new therapeutic development for targeting NMIIC and NMIIB in mechanically adaptive cell types