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THE EFFECTS OF UNITED STATES INTERVENTION IN HONDURAS: WHAT CAN THE U.S. LEARN FROM THE AFTERMATH OF THE 2009 COUP?
No full textThis thesis analyzes the long-term consequences of United States intervention in Honduras, arguing that U.S. foreign policy contributed to widespread political and economic instability that led to the 2009 coup d'etat. Drawing from historical context dating back to the late 19th century, this research highlights the evolution of U.S. influence through capitalist interests, militarization of domestic institutions, and neoliberal policy. The analysis explores how the United States continuously prioritized geopolitical and economic interests over human rights, often supporting corrupt regimes in Honduras. Key patterns are identified through scholarly sources, historical parallels, and media analysis. The thesis highlights the ways in which silence and a lack of true media representation perpetuated harm. It offers recommendations for future foreign policy that surround accountability and transparency. Understanding the history of U.S. intervention in Honduras is necessary in order to avoid the repetition of it, and to form a path forward that protects human rights across Latin America
Aerodynamic Measurements in a Wing Encountering a Wind Gust and Blowing Jets
No full textThis study investigates a wing's unsteady aerodynamics during discrete gust events and evaluates active flow control (AFC) for gust load alleviation. Wind gusts create critical loads impacting aircraft stability, control, and structural integrity. The objective was to characterize the aerodynamic response to a regulatory gust profile and compare AFC strategies for lift suppression. Experiments in a subsonic wind tunnel used a servo-actuated gust generator to produce repeatable 1-cos gusts meeting FAA and EASA standards. Multiple NACA 0012 half-span wing models were used, including rigid aluminum and flexible PLA short-span (c = 0.156 m) and long-span (c = 0.203 m) versions. A five-degree-of-freedom force balance measured aerodynamic forces, and hot-wire smoke provided flow visualization. The baseline response without flow control featured a significant lift overshoot during gust encounters. At a gust ratio of GR=0.075, the peak lift coefficient exceeded the steady-state maximum by 27% for the short-span wing at an initial angle of attack of 10 degrees, and up to 54% for the long-span wing at 16 degrees. Flow visualization revealed this phenomenon is driven by leading-edge vortices that maintain flow attachment beyond the static stall point, causing the lift overshoot. The response showed distinct hysteresis loops governed by the reduced frequency (k). The short-span model (k = 0.30) produced a characteristic figure-eight hysteresis loop, whereas the long-span model with its higher reduced frequency (k = 0.38) displayed a single, more rounded counterclockwise loop. This transition confirms the critical role of unsteadiness, with higher reduced frequencies leading to greater phase lag and lift enhancement. Two flow control strategies using steady jets were evaluated: normal blowing at the quarter-chord and upstream blowing near the leading edge (x/c =0.08). Upstream blowing showed superior efficacy. While normal blowing gave a modest 10.6% peak lift reduction, it created an adverse nose-down pitching moment, degrading stability. In contrast, upstream blowing was substantially more effective, achieving a peak lift reduction up to 23.7% at an initial angle of attack of 16 degrees. The upstream jet's effectiveness increased at higher angles of attack. This superior performance is attributed to the counter-flow jet's ability to destabilize the leading-edge shear layer globally, promoting controlled flow separation that weakens the suction peak. Additionally, upstream blowing enhanced pitch stability by reducing the nose-down pitching moment. These findings position upstream blowing as a promising technique for alleviating adverse aerodynamic loads induced by severe gust encounter
Investigating Cyclospora cayetanensis in Environmental Waters: Molecular Detection and Genotyping
No full textWithin the last decade, there has been a continuous increase in Cyclospora cayetanensis cases associated with the consumption of fresh produce grown within the U.S. Environmental sources of contamination beyond fresh produce in the U.S. has not been extensively examined, and this thesis aims to evaluate available molecular detection methods for C. cayetanensis in environmental waters prior to a surveillance study conducted in the Western U.S. California. Currently available genotyping methods for C. cayetanensis utilize a multi-locus sequence typing approach that was evaluated only on human stool samples and need to be evaluated for environmental water matrices to support secondary confirmation and traceback investigations. To assist, our study described in Chapter 2 assessed 10 biomarkers’ performance for genotyping C. cayetanensis in environmental waters, which comprised of 9 from the CDC’s genotyping panel for human stool, consisting of 6 nuclear (CDS-1, CDS-2, CDS-3, CDS-4, HC378, HC360i2) and 3 mitochondrial (MSR, Cmt_534, Cmt_109) biomarkers, as well as one from the FDA mit3PCR for irrigation waters. Successful sequencing and identification of the parasite from secondary sequence confirmation is necessary subsequent to molecular detection with qPCR for environmental samples as the standard 18S rRNA qPCR assay is suspected to cross react with closely related parasites, and the replacement Mit1C qPCR assay targeting the Cox3 gene was yet to be validated for environmental waters. When evaluating results with the Geneious and Bowtie2 mapping algorithms, C. cayetanensis was sufficiently sequenced and confirmed with biomarkers CDS-1 (8/24; 33.3%), CDS-2 (1/24; 4.17%), CDS-3 (7/24; 29.1%), and CDS-4 (7/24; 29.1%) among 14/24 (58.3%) irrigation water samples presumptively positive by 18S rRNA qPCR, and of which none were positive with the Mit1C qPCR assay. Accordingly, we demonstrate the potential of the CDS markers for genotyping C. cayetanensis in environmental waters and potential cross-reactivity with the 18S rRNA qPCR. With the need for a highly specific and sensitive molecular detection tool, the FDA updated the Mit1C qPCR assay as a replacement standard method for molecular detection in environmental waters. As adapting their protocol optimized for the ABI-7500 instrument to more common real-time PCR platforms will broaden research and testing capabilities, in Chapter 3 study, we optimized the Mit1C real-time PCR protocol under ideal clean conditions on our Bio-Rad CFX-96 platform and compared to the ABI-7500 platform. Results indicate that the Mit1C real-time PCR assay performed best with a reduced annealing temperature of 66°C for the Bio-Rad CFX-96, where no optimization and direct adaptation of the Mit1C real-time PCR protocol for the ABI-7500 platform using 67°C could not detect as high as 200 oocysts spiked in irrigation water. With our established tools for molecular detection and sequence confirmation, Chapter 4 describes the study where we then determined the occurrence of C. cayetanensis in environmental water and portable toilet surfaces (fomites) as potential modes of transmission in the Western U.S. California fresh produce growing region. A total of 235 samples including surface water (n=119), reclaimed water (n=41), fomites (n=74), and sludge (n=1) were collected and processed in accordance with the FDA BAM Chapter 19c (July 2020 edition) that describes methods for filtering oocysts, concentrating, and DNA isolation. Molecular detection of C. cayetanensis proceeded with the optimized Mit1C qPCR protocol and a previously developed in-house ITS-2 region qPCR assay. Results indicate no detection of C. cayetanensis in all samples by Mit1C qPCR, where the ITS-2 qPCR assay had very high Cq values for three surface water and one sludge samples. These ITS-2 qPCR positive samples are determined as presumptively positive without supporting sequencing data. C. cayetanensis was not confirmed in reclaimed water and portable toilet surfaces. In summary, this thesis establishes the molecular tools for detecting C. cayetanensis in environmental waters, confirmed its prevalence in Southeast U.S. Florida irrigation waters, and identified presumptive positives in Western U.S. California irrigation water and sludge samples from a fresh produce growing region. Further examination of the parasite in environmental samples is needed to fully determine environmental modes of transmission
Imagining Climate Futures: Worldmaking Through Community-Based Storytelling and Climate Fiction
No full textClimate fiction, or Cli-Fi, is a subgenre of science and speculative fiction that exploresthemes of environment, climate change, and society. Narratives associated with the genre can exist on a spectrum ranging from apocalyptic to utopian in nature, often critiquing modern society and portraying aspects of personal and community resilience, social and environmental justice, technology, and adaptation in times of crisis. As the world continues to face rising temperatures, more frequent and extreme weather events and natural disasters, as well as political and social unrest globally, climate nihilism and so-called “doomerism” can take hold, leaving people and communities feeling hopeless and powerless about the future. With a greater call in climate change scholarship for new and imaginative ways of understanding, knowing, and working with climate change, this document offers a case study using storytelling practices and fiction-writing to develop experiential forms of knowledge about climate change. In the spirit of Cli-Fi anthology collections that illustrate uncertain, critical, and resilient futures, Imagining Climate Futures is a research project designed to invite participants to engage in creative,
imaginative, and collaborative storytelling practices to envision possible futures that reflect the experiences, knowledge, ideas, and values of those involved. This thesis discusses the process of working with participants to engage in speculative and creative storytelling practices rooted in lived experiences and centered around climate change and climate futures, providing an opportunity to learn from one another and expand on personal and collective visions of the future in light of the climate crisis
Novel Mechanisms for Extracellular NAMPT Secretion
No full textThis thesis dissertation is focused upon nicotinamide phosphoribosyltransferase (NAMPT), an ancient pluripotent enzyme present in multiple organisms composed of eukaryotic cells from simple genome-structured organisms, such as yeast, to complex biological systems such as humans. NAMPT is a foundational intracellular metabolic rate-limiting enzyme that converts nicotinamide (NAM) to nicotinamide mononucleotide (NMN) to supplement and maintain cellular NAD+ levels that are required for survival. An organism’s main source of NAD+ is gathered from NAM or nicotinic acid (NA) within dietary sources containing amino acid tryptophan with NAD+ critical for both eukaryotic and prokaryotic cellular energy metabolism. NAMPT utilizes NAM, NA, and nicotinamide riboside (NR) to synthesize NAD+ within the classical NAD+ salvage pathway to maintain cellular NAD+ levels. Beyond NAMPT’s well-defined intracellular function, when NAMPT is secreted/released extracellularly, eNAMPT serves as a novel damage-associated molecular pattern protein (DAMP) to regulate innate immunity, inflammatory, fibrotic, and neoplastic responses via ligation of the pathogen recognition receptor, TLR4. DAMPs are molecules that are released from damaged or dying cells due to trauma or pathogen triggering infections, to activate the innate immune response, and to potentially promote pathological inflammatory responses. Secreted levels of eNAMPT into the bloodstream directly influence the severity of the immune response and contribute to disease severity. Elevated plasma levels of eNAMPT serve as a biomarker of disease activity in patients (and pre-clinical models) with acute respiratory distress syndrome, sepsis, systemic lupus erythematosus, diabetes, sarcoidosis, lung, and hepatic fibrosis, chorioamnionitis, inflammatory bowel disease, and pulmonary hypertension. Based upon eNAMPT’s influence on innate immunity and disease severity, the graduate studies contained in this thesis sought to decipher the key mechanisms that regulate eNAMPT secretion/release as these events are fundamental to understanding eNAMPT’s involvement in human disease. These studies focused on unconventional protein secretion (UPS) mechanisms as NAMPT does not contain an endoplasmic reticulum (ER) mRNA signal sequence and conventional protein secretion mechanisms were ruled out. Specifically, Type 1 (self-sustained membrane translocation) and Type 3 (autophagy-based secretion) mechanisms were investigated. Utilizing human monocytic THP-1 cells as the platform for eNAMPT secretion, we demonstrated that eNAMPT release during pyroptosis evoked by Nigericin, and eNAMPT secretion by lipopolysaccharide (LPS, non-pyroptotic), requires NLRP3 inflammasome activation with substantial attenuation by NLRP3 inhibition (MCC-950). ENAMPT secretion/release was attenuated by targeted genetic deletion of key inflammasome components, including NLRP3, caspase-1, or gasdermin D (GSDMD). Pyroptosis-associated eNAMPT release involved cleavage of the pore-forming GSDMD protein resulting in plasma membrane rupture (PMR) whereas non-pyroptotic LPS-induced eNAMPT secretion involved neither GSDMD cleavage nor PMR (verified utilizing noncleavable GSDMD mutant constructs) but was highly dependent upon NAMPT ubiquitination catalyzed by a complex containing the NEDD4 E3 ligase, Hsp90 (a selective chaperone), and intact GSDMD verified by enzymatic inhibition or silencing of NEDD4, GSDMD, or Hsp90. NAMPT ubiquitination and secretion involves the activation of LC3 lipidation as super-resolution microscopy analyses demonstrate NAMPT co-localization with autophagosome marker LC3B. Additionally, eNAMPT secretion was significantly reduced by targeting inhibition of LC3 lipidation E1 and E3 enzymes, ATG5 and ATG7, respectively. In summary, this body of work represents major components of an eNAMPT secretion pathway via TLR4 ligation and NAMPT’s metabolic role in the inflammatory response as an immunomodulatory cytokine. These studies provide key insights into eNAMPT secretion that may accelerate the development of therapeutic strategies that address unmet therapeutic needs in inflammatory, fibrotic, and neoplastic disorders
POTENTIAL EFFECTS OF METHANE EMISSION REDUCTION ON CALIFORNIA LEAST TERN BREEDING HABITAT
No full textEffective climate change mitigation is complicated by economic factors, as renewable energy projects require significant upfront investment. Recently, the Bitcoin mining industry has begun investing in renewable energy, particularly projects powered by methane waste byproducts from other industries. These projects are promising for their low infrastructure needs and ability to reduce methane emissions that would otherwise be released into the atmosphere.
Programs like the Endangered Species Act’s Cooperative Endangered Species Conservation Fund provide funding for conservation projects benefiting endangered species. These programs could support methane-fueled Bitcoin mining projects if a link between methane reduction and improved habitat for endangered species is established.
This study used GIS to assess the impact of methane reduction on the breeding habitat of the California least tern, an endangered bird species. Using data from the Coupled Model Intercomparison Project Phase 6 (CMIP6) climate modeling project, potential future habitat in 2050 was mapped under three projected climate scenarios developed by CMIP6 scientists. Alternative scenarios with 10%, 20%, and 50% reductions in methane emissions were then modeled using the Model for the Assessment of Greenhouse Gas Induced Climate Change (MAGICC) climate model for comparison with the unaltered versions.
In two of the three scenarios, reducing methane emissions expanded the likely breeding habitat of the California least tern. However, in the third scenario, habitat suitability showed minimal change. This suggests that methane-fueled Bitcoin mining could be an effective climate change mitigation strategy, potentially improving habitat for endangered species, but further research is needed to confirm these findings.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]
Investigating Trends, Causes, and Patterns of Idaho Wildfires
No full textWildfires have become increasingly more common in much of the West, posing a large threat to both human and natural resources. This study uses a variety of spatial statistical methods to investigate the patterns, trends, and causes of wildfires across the state of Idaho. Leveraging tools such as the Global Moran’s I and Hot Spot Analysis to identify significant clusters and emerging trends of fire patterns, Standard Deviational Ellipses were also employed to show the dispersion and orientation of wildfire occurrences. Regression analysis, including ordinary least squares (OLS) and geographically weighted regression (GWR), was used to examine how fire management practices influence the spatial patterns of wildfire incident sizes. The results indicate that human and natural-caused fires exhibit reverse patterns: human-caused fires tend to be smaller but more costly, whereas natural-caused fires tend to be larger but less costly. Unsurprisingly, human fires tend to be concentrated around higher population densities, while natural fires tend to occur in more remote areas. These findings highlight the importance of more localized and data-driven approaches to wildfire management and policy decision-making.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]
REDLINING AND EDUCATION: INVESTIGATING THE LONG-LASTING IMPACT OF HISTORICAL HOUSING POLICIES IN HENNEPIN COUNTY
No full textThe U.S. government created the Home Owners' Loan Corporation (HOLC) as part of the New Deal under President Franklin D. Roosevelt. HOLC refinanced home mortgages to prevent foreclosures and stabilize the housing market. However, its practices, particularly redlining, had long-lasting negative effects on many minority communities. HOLC's grading system, which relied on discriminatory criteria based on racial composition and economic status, marginalized communities of color. The legacy of these practices continues to shape socioeconomic conditions today, as redlined neighborhoods still struggle with lower property values, limited access to resources, and persistent disparities in education, wealth, and healthcare. These enduring effects underscore the long-term consequences of institutional discrimination, which continue to impact affected communities across generations. This study examines the lasting effects of redlining on educational attainment in Hennepin County, part of the Twin Cities in Minnesota, by analyzing decennial census and American Community Survey data. The analysis focuses on key factors at the census tract level, including socioeconomic variables such as housing, employment, and income; demographic factors like race and disability; and access to resources, including technology and transportation. Using regression models, the study identifies significant relationships between these variables and low educational attainment. The results reveal that both low educational attainment and the associated variables vary spatially across Hennepin County.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]
Learning from Rip Currents to Wayfind Higher Education: Towards an Onto-Epistemology of Oceana
No full textWith the goal of healing and reasserting my connectedness/communion with Oceana ways of being and knowing, this study sought to identify experiences in which I conflicted with coloniality and then reconceptualize those experiences as rip currents from which to understand a system’s “shape of the bottom” (the foundation a school is built upon); “the waves and weather conditions” (the climate-social, political, economic); and “people-made obstacles that cause a shadow or deflection” (the policies we enact) so that I may transform the system itself. Further, by engaging in Critical Autoethnography as Wayfinding, I engaged in deep reflection to interrogate how I find my way in higher education and how my wayfinding can be better integrated with Oceana (from the ocean) ways of being and knowing. This study has three key findings: 1) lessons from rip currents; 2) how rip current lessons inform how I wayfind in Higher Education; 3) Oceana onto-epistemology. This study ultimately concludes that if we want educational system change and the creation of thriving, equitable, dynamic learning environments, then we need onto-epistemologies that exist outside the imperialist, colonial onto-epistemology that is at the heart of current educational design
Exploring Grief Witnessing Among Black Americans
No full textBlack Americans grieve at alarmingly high rates due to mortality disparities, yet are often denied the opportunity to grieve openly. Limited access to responsive support may compound the challenges. The presence of a witness, who recognizes the loss and affirms the griever’s right to feel and express their grief, may be beneficial. The present study tested if the number and quality of witnesses would influence grief severity for Black Americans. Participants (N= 95) who identified as Black were recruited through referrals from Black community institutions, word-of-mouth dissemination, local events and engaging with Black community leaders. In an online survey, participants provided loss history, witnessing experiences, and prolonged grief symptoms. Participants (N=10) participated in follow-up semi-structured interviews. Predictors of prolonged grief severity, including number of witnesses, age, and months since loss, yielded a statistically significant model. Additionally, evaluating the effect of witness quality on grief severity found overall model significance (F (3,91) = 6.33, p = 0.001.) Results showed that higher reported witness quality was associated with lower grief severity scores (? = -0.2, SE = 0.05, p < 0.001). Qualitatively, 7 themes were identified, illustrating the qualities of the griever’s witnesses, including a shared identity with the griever, and having known the deceased. Findings suggest that a quality witness can reduce grief severity. The presence of witnesses provides affirming emotional support and ensures the person’s grief is not disenfranchised. More witnesses may be a protective factor. The specific qualities of the witness, as identified by the bereaved individual, may enhance the understanding of how witness qualities validate and acknowledge their grief