Open Research Oklahoma (Oklahoma State Univ.)
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Infrasound noise mitigation and the characterization of heliotrope flight dynamics
No full textCurrently, seismic measurements on Venus are limited due to the extreme conditions on its surface. Nevertheless, there exists an opportunity for exploration and study of the interior of Venus by deploying microbarometers at high altitudes within the Venusian atmosphere. This offers the potential to detect infrasound, enabling insights on the interior structure of the planet. Consequently, the Balloon-based Acoustic Seismology Study (BASS) flight campaign was aimed at detecting the acoustic signature from natural earthquakes from heliotropes floating in the lower stratosphere, as an earth-analog experiment for detecting seismicity on Venus using balloons. Heliotropes are passive solar hot air balloons that are capable of achieving nearly level flight within the lower stratosphere for several hours. These inexpensive flight platforms enable stratospheric sensing at scale, but their performance has not yet been assessed systematically. During the summer of 2021, 29 heliotropes were launched from Oklahoma and achieved float altitude with data. All of the heliotrope envelopes were nearly identical with only minor variations to the flight line throughout the campaign. This creates a relatively large sample size for this new technology to characterize the typical flight behavior during launch, ascent, float, and descent. Each flight stage is characterized, dependence on various parameters quantified, and discussion of nominal and anomalous flights provided.Compared to ground-based remote sensing, high altitude balloons are nominally considered a low-noise sensing platform due to their ability to drift with the local air. However, to resolve the direction of arrival, a long flight line is required to create sufficient separation between sensors. This separation increases the relative speed for the lower sensor, and on Venus the higher shear and air density pose challenges as they will amplify that effect. This increase in noise also increases the potential for contamination of measurements. The current work reports on the development and evaluation of compact, lightweight windscreen designs for use on high altitude solar balloons. Presented are laboratory, ground-based field testing, and a preliminary flight test of three new windscreen designs. Their performance is quantified with a measure of their wind noise reduction and attenuation of coherent sounds
Tasks associated with teaching school-based agricultural education: A modified Delphi study
No full textSchool-based agricultural education (SBAE) teachers experience heavy workloads (Torres et al., 2008) and challenges (Boone & Boone, 2009) related to teaching SBAE. As such, SBAE teachers experience continual needs (Traini et al., 2021) and expectations that are ever changing (Eck et al., 2019). Such expectations can cause strain on teachers (Traini et al., 2021) and lead to high levels of stress and burnout (Croom, 2003). Although the tasks of teaching SBAE can be inferred from the above-mentioned needs, challenges, and characteristics, limited literature exists detailing the specific tasks SBAE teachers are expected to perform. Therefore, we sought to identify the specific tasks expected of SBAE teachers within the program (i.e., classroom and laboratory, FFA, and SAE), as well as the other professional responsibilities associated with teaching. Human Capital theory was used to frame the study, specifically task-specific human capital which asserts that “. . . some of the human capital an individual acquires on the job is specific to the tasks being performed . . .” (Gibbons & Waldman, 2004, p. 203). A modified, three-round Delphi method was used to meet the objectives of the study. The panelists consisted of doctoral students in agricultural education with at least three years of SBAE teaching experience. The expert panel consisted of 23 individuals meeting these criteria. The final list of tasks associated with teaching SBAE included 238 items achieving consensus in 47 themes across the four question areas (216 tasks reached the consensus of agreement threshold in Round 2, and an additional 22 tasks achieved consensus of agreement in Round 3). In total, 74 tasks populated classroom and laboratory instruction, 80 tasks populated FFA, 45 tasks populated SAE, and 39 tasks populated other professional responsibilities. In all, 110 tasks and six themes failed to reach consensus of agreement and were eliminated from the study. The beliefs the panel of experts hold regarding the tasks of SBAE teachers point to a single, overarching conclusion: there are too many expectations placed on SBAE teachers
Novel Ca²⁺ sensor controlling iron uptake in Pseudomonas aeruginosa, a human pathogen
No full textPseudomonas aeruginosa is a Gram negative, opportunistic pathogen which causes a wide range of severe infections in humans. These infections are difficult to treat and, especially in the lungs of cystic fibrosis (CF) patients, often become chronic. Complicating eradication of P. aeruginosa is pyoverdine, a virulence factor which aids bacterial iron acquisition in iron-limited environments. Previous work has shown that pyoverdine production in P. aeruginosa strain PAO1 is increased under elevated levels of Ca²⁺, as are found in the pulmonary fluids of CF patients. A Ca²⁺-binding EF-hand protein, EfhP (PA4107), was demonstrated to be critical for the Ca²⁺-regulated virulence in PAO1. This study seeks to characterize EfhP regulation of the P. aeruginosa response to Ca²⁺, particularly pertaining to critical iron uptake pathways. We have established that deletion of efhP significantly hinders PAO1 pyoverdine production when grown at high Ca²⁺ in BMM8 medium. Pyoverdine is a fluorescent molecule quantified by measuring fluorescence at 400 nm excitation/460 nm emission and normalized by OD600. The presence of efhP in several CF clinical isolates was confirmed with PCR using efhP-specific primers. We observed that these clinical isolates also show increased pyoverdine production at 5 mM Ca²⁺ vs. the no Ca²⁺ condition. In the clinically relevant synthetic cystic fibrosis sputum medium (SCFM), PAO1 shows increased pyoverdine production with increasing Ca²⁺ concentrations. In the future, we aim to identify specific sequences in the efhP gene that are most important to the regulation of pyoverdine production by testing a series of strains expressing mutated EfhP. We also plan to evaluate expression of efhP in CF clinical isolates and test for their pyoverdine production when cultured in SCFM. The new knowledge gained can support further studies to develop novel efficient medications to improve the quality of life of CF patients who struggle with chronic P. aeruginosa infections.Lew Wentz FoundationMicrobiology and Molecular Genetic
Determine the role of senescent cells in the Rostral Ventrolateral Medulla (RVLM) in mediating neuroinflammation and sympathoexcitation in obesity
No full textObesity is the major risk factor for the development of cardiovascular diseases like hypertension, coronary artery disease, atrial fibrillation, and chronic heart failure. It is estimated that 65-78% of obese adults are hypertensive, however the underlying mechanisms are still unclear. Accumulating evidence suggests that increase in sympathetic nerve activity (SNA) plays a crucial role in the pathophysiology of obesity-induced hypertension. Rostral Ventrolateral Medulla (RVLM) is a key region within the brainstem that is responsible for basal and reflex control of sympathetic activity associated with cardiovascular function. Cellular senescence is a state of the cells that is characterized by a permanent, irreversible cell cycle arrest in proliferative cells in response to various stress-inducing stimuli and can produce inflammation. In high fat diet (HFD) fed obese mice, we have observed increased cellular senescence at the level of RVLM along with elevated sympathetic nerve activity and blood pressure. The major goal of my Ph.D. is to understand the role of senescent cells in the RVLM in mediating neuroinflammation and sympathoexcitation in obesity. Based on this preliminary data, in our first set experiment, we treated the HFD fed animals with a senolytic drug combination (dasatinib and quercetin) and found that this senolytic treatment attenuated the sympathoexcitation and systolic blood pressure. In the second set of experiments, we employed a transgenic mice model (p16-3MR) to specifically target the p16 senescent cells and study its role on sympathoexcitation in obesity. We found that with the removal of senescent p16 cells using ganciclovir attenuated obesity-induced sympathoexcitation. Lastly, we employed a cell culture model with human brainstem astrocytes to determine the molecular mechanisms behind obesity-induced sympathoexcitation. We treated the cells with the primary saturated fatty acid palmitic acid) in most diets to mimic obesity and found that it induced cellular senescence and in addition reduced glutamate transporter expression (EAAT1 and EAAT2) suggesting a possible mechanism for sympathoexcitation in obesity. Taken together our results shed light on the important role of senescent cells in the RVLM and the harmful effects of sympathoexcitation in obesity. The senolytic treatments could be a new therapeutic strategy will break new ground in the development of novel interventions against hypertension in obese individuals
Essays in applied microeconomics and development economics
No full textMy dissertation contributes three Essays in Applied Microeconomics and Development Economics literature. In my first chapter, I use a policy experiment from the Indian state of Bihar's complete alcohol prohibition law (enacted in October 2016) to estimate the causal effects of alcohol ban on the prevalence of domestic violence against women using the most recent three rounds of the Indian National Family Health Survey (NFHS). I find that prohibition significantly reduced alcohol consumption, particularly from market channels, resulting in reduced violence against women by their husbands. My results are robust to numerous checks, including randomized inference and changing control groups. The second chapter investigates the severe issue of air pollution in India caused by crop residue burning and its significant impact on public health. Using district-level panel data spanning 2002 to 2020 from household surveys and high-resolution satellite data, my study reveals a concerning trend: despite regulations, agricultural fires are on the rise. These fires contribute to a significant 10% increase in infant mortality rates, causing over 60,000 infant deaths in India annually. Eliminating crop residue burning could lead to annual savings of USD 9.3 billion. Investigating farmers' attitudes, I found that while they acknowledge burning's health risks, short-term economic gains override long-term concerns. To counter this, I suggest a Coasean-based solution, involving incentives like cash rewards and technological aid for safe residue disposal. The third chapter of the study delves into India's "calorie consumption puzzle" by analyzing consumer spending surveys from 1987-88 to 2011-12. The research employs the quadratic form of almost-ideal demand systems (QUAIDS) with endogenous regressors to estimate food demand. The study investigates how a 10% price increase influences food demand and nutritional intake for various food groups. Notably, it uncovers significant price sensitivity in food groups like milk, eggs, meat, fish, pulses, fruits, and vegetables, with cereals being less price-sensitive due to their staple status. The research identifies cross-price elasticity effects, particularly in rural areas, affecting consumption patterns for high-value commodities and pulses. Price hikes are also found to impact protein and fat shares, especially in rural areas. Additionally, increased income leads to higher demand across all food groups, affecting calorie, protein, and fat intake. These findings contribute vital insights to the literature on how economic factors shape dietary choices and nutritional intake
Role of the Mycobacterium tuberculosis ESX-4 secretion system in heme iron utilization and pore formation by PPE proteins
No full textMycobacterium tuberculosis (Mtb) is transmitted through aerosols and primarily colonizes within the lung. The World Health Organization estimates that Mtb kills ~1.4 million people every year. A key aspect that makes Mtb such a successful pathogen is its ability to overcome iron limitation mounted by the host immune response. In our previous studies, we have shown that Mtb can utilize iron from heme, the largest source of iron in the human host, and that it uses two redundant heme utilization pathways. In this study, we show that the ESX-4 type VII secretion system (T7SS) is necessary for extracellular heme uptake into the Mtb cell through both heme utilization pathways. ESX-4 influences the secretion of the culture filtrate proteins Rv0125 and Rv1085c, which are also necessary for efficient heme utilization. We also discovered that deletion of the alternative sigma factor SigM significantly reduced Mtb heme utilization through both pathways and predict that SigM is a global positive regulator of core heme utilization genes of both pathways. Finally, we present the first direct evidence that some mycobacterial PPE (proline-proline-glutamate motif) proteins of the PPE protein family are pore-forming membrane proteins. Altogether, we identified core components of both Mtb Heme utilization pathways that were previously unknown and identified a novel channel-forming membrane protein of Mtb. IMPORTANCE M. tuberculosis (Mtb) is completely dependent on iron acquisition in the host to cause disease. The largest source of iron for Mtb in the human host is heme. Here, we show that the ancestral ESX-4 type VII secretion system is required for the efficient utilization of heme as a source of iron, which is an essential nutrient. This is another biological function identified for ESX-4 in Mtb, whose contribution to Mtb physiology is poorly understood. A most exciting finding is that some mycobacterial PPE (proline-proline-glutamate motif) proteins that have been implicated in the nutrient acquisition are membrane proteins that can form channels in a lipid bilayer. These observations have far-reaching implications because they support an emerging theme that PPE proteins can function as channel proteins in the outer mycomembrane for nutrient acquisition. Mtb has evolved a heme uptake system that is drastically different from all other known bacterial heme acquisition systems.Microbiology and Molecular Genetic
Bondage and balm: A feminist narrative inquiry of midlife women, domestic labor, and health during COVID-19
No full textAmong the many things we do not understand about COVID-19 is how pandemic-era domestic pressures manifest in the already-pressurized lives of women at midlife, a life stage characterized in the health literature as a period of great risk and tremendous possibility. Research conducted since the pandemic began indicates a number of factors, including a lopsided-by-gender domestic workload and sandwich generation caregiving demands, that could impact the health of midlife women. The purpose of this feminist qualitative study was to explore women’s experiences of the health impacts of their greater, disproportionate, and gendered pandemic domestic labor workload. To fulfill that purpose, I asked this research question: How do midlife women story the health impacts of their pandemic domestic labor? To answer this, I used feminist narrative inquiry guided by The Listening Guide methodology and methods. Narrators were five midlife women (defined for the purposes of this study as being 40 to 64 years old). I gathered each narrator’s stories during a series of four interviews. Each interview covered a period within the first 15 months of the pandemic. From these interviews, I harvested I-poems that foreground women’s voices and crystallize their experiences of pandemic domestic labor. Together with repeated listenings and readings of the interview recordings and transcripts, these analytic devices helped me to extract the layers of narrators’ experiences. What I heard from them became the four “listening layers” into which I organized the core findings of my study. This study foregrounds the details of women’s lives and takes seriously the connections between the domestic and women’s health. It considers the significance of space and women’s ongoing struggle to navigate their needs for sharing domestic labor with others in their households. Finally, it recognizes “seeing” domestic needs as a form of labor and makes visible the connection of seeing and doing domestic labor to the valuation of the women and their needs. This project unfolded during the pandemic as I shared these domestic and health challenges, reclaimed my identity by transitioning my name from Rebek to Lavish, and recognized the ongoing health implications of domestic labor
Saturated hydraulic conductivity of soil under different vegetation cover types – Juniperus virginiana, Quercus stellata, Panicum virgatum, and native tallgrass prairie
No full textSaturated hydraulic conductivity (Ksat) is a key component in landscape hydrology, which necessitates a better understanding of the variables that drive changes in Ksat. The objective of this thesis was to investigate different vegetation, soil, chemical, and biological variables that influence Ksat on the watershed scale in the southern Great Plains. I measured Ksat, analyzed soil texture, pH, ammonium, organic matter, and bulk density, and determined tree canopy cover, tree basal area, herbaceous species richness, herbaceous species diversity, root content, and gravel fraction. These samples were taken from eight experimental watersheds at the Cross Timbers Experimental Range, Stillwater, Oklahoma. The watersheds consisted of two replicates of four different vegetation types: tallgrass prairie, oak woodland, eastern redcedar (Juniperus virginiana) woodland, and switchgrass (Panicum virgatum). Ksat was significantly related to watershed vegetation cover type (eastern redcedar > tallgrass prairie > oak > switchgrass). When looking at all vegetation cover types, tree basal area, tree canopy cover, and soil pH were significantly correlated to Ksat. When just forest watersheds were considered, bulk density, gravel fraction, basal area, pH, herbaceous species richness, and herbaceous species diversity were correlated to Ksat. When just the grassland points were considered, silt, organic matter, and herbaceous species diversity were significantly correlated to Ksat. Overall, Ksat was spatially variable and likely influenced by many different factors. However, vegetation cover type at larger scales can be used to predict watershed-level Ksat and therefore assess its potential impact on surface runoff
Basic finding aid clean-up using OpenRefine
No full textIn this session, we’ll explore some accessible and basic functionality within OpenRefine – an open source tool for cleaning up messy data – that allows archivists to take control of their finding aids and move more easily into a structured data environment. This is a great tool for anyone working to move legacy finding aids from a variety of formats (pdf, word doc, spreadsheet, access database, etc.) into a more structured spreadsheet format, significantly speeding up the process of moving into EAD. We’ll look specifically at moving from a pdf, but the functions can be applied much more broadly.Librar
Are electrocardiograms accurate in detecting cardiac pathologies in athletes ages 13-25: A critically appraised topic
No full textClinical Scenario: Electrocardiograms (ECGs) have become increasingly utilized in pre-participation exams for athletes in settings ranging from secondary schools to professional sport. Historically, this diagnostic modality has been effective when used properly and interpreted accurately in other healthcare settings. ECGs have the potential to accurately detect athletes who possibly have underlying cardiac pathologies. The aim of this review is to identify if ECGs can accurately detect cardiac pathologies in those athletes who are between the ages of 13-25. Challenges and positive outcomes are interpreted and highlighted throughout the review.ClinicalQuestion: Are ECGs accurate in detecting cardiac pathologies in athletes ages 13-25?Summary of Key Findings: ECGs proved accurate in detecting cardiac pathologies. In the studies surveyed comparing ECGs with other diagnostic criteria, the ECG performed better and assisted physicians in diagnosing cardiac pathologies. However, more research is needed to conclude if ECGs can be used to diagnose cardiac pathologies without the use of other modalities or examinations.Strength of Recommendation: Based on the evidence presented the strength of recommendation is a grade B, or moderate quality of information. Collectively, these studies possessed moderate limitations but were able to support the inclusion of ECGs in cardiac of health of athletes ranging in ages 12-25