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Gas Evolution of a Nickel-Zinc Cell
No full textBatteries are a foundational technology in some of the industries most essential to humanity. Often, their advancement to achieve better performance impacts human lives positively. There are a wide variety of battery chemistries that have been utilized, and the differences in their properties have caused them to be used in many distinct niche applications. Nickel-Zinc (NiZn) batteries are desirable because of their recyclable materials, high cell voltage, and high cycle-life. However, it experiences undesirable shape-change of its electrode materials and gas production due to the electrolysis of the aqueous electrolyte. These can lead to a decrease in capacity over many cycles and an increase in the resistance of the electrolyte, causing energy loss when cycling. The gasses produced in a NiZn cell are diatomic hydrogen (H2) and oxygen (O2) that must be either vented or recombined into water with an internal catalyst. There is a lack of work done to study the gassing behavior of a NiZn cell during cycling. An understanding of the gassing mechanisms may help with their mitigation. In this project, I created a computational model that primarily incorporates Butler-Volmer kinetics and the Nernst equation to simulate gas production from a NiZn cell while cycling at different rates. I also developed a method to sample the gas produced from a NiZn cell while cycling and measure its composition with a quadrupole mass spectrometer. In both, H2 was produced at the nickel cathode while discharging, but no O2 was produced. Both gasses were produced during charging with H2 being produced at the zinc anode the entire charge and O2 being produced rapidly at the cathode towards the end of charge. Recombination events of these gasses at a platinum catalyst in the cell was well identified during cycling. The model proved to be insightful when making predictions on NiZn gassing behavior, and its results agreed with experimental data. The mass spectrometer was shown to be a powerful tool for the identification of gas production and recombination of a NiZn cell
Carbaryl-Induced Leaf Necrosis in Vitis Rupestris B-38
No full textAgricultural insecticides are formulated to target insects while minimizing harm to the intended crop. In rare instances, however, insecticides induce harmful physiological reactions in certain plant genomes, inflicting severe tissue damage. This project investigated the genetic basis of such a reaction observed in the grape genotype Vitis rupestris B38 following exposure to the insecticide carbaryl, which manifests as interveinal leaf necrosis. Through analysis of an F1 hybrid progeny of this grapevine, I mapped this phenotype to a QTL on chromosome 16. The carbaryl-sensitive trait was repeatedly mapped to the same locus using phenotype data from two different field locations and from an in vitro bioassay. RNA-seq and gene ontology enrichment analyses revealed the activation of various defense- and stress-related mechanisms, and strongly suggested the involvement of salicylic acid- and jasmonic acid-dependent defense responses. The RNA-seq data suggested a misdirected hypersensitive response (HR) in sensitive plants; differentially expressed genes (DEGs) associated with plant pathogen defense pathways further support this speculation. However, RT-qPCR analysis of NDR1/HIN1-like protein 6 gene expression did not validate the involvement of such pathways, therefore, further molecular analysis is needed to fully elucidate the underlying mechanisms of carbaryl sensitivity. Altogether, the findings of this thesis highlight the intricate interplay of plant defense pathways in response to xenobiotic stressors and emphasize the ecological significance of plant-insecticide interactions
Exploring Band Students\u27 Motivations Regarding Instrument Selection
No full textWhen choosing a beginning band instrument, students are faced with a choice that may be influenced by a variety of factors. These factors also interest band directors, who want students to choose an instrument that will be a good fit for their strengths while also being engaging to them. To assist directors in guiding students through instrument selection it is helpful to know what factors could influence students when they are choosing an instrument. To identify the factors that students report as impactful, beginning band students in five northwest Missouri school districts were surveyed about the influence of selected factors. Students reported being most influenced by their perceived enjoyment of playing their instrument, followed by instrument timbre. Other influential factors included the perceived ease of students’ chosen instruments, parents and other family members, and band directors. Male and female students reported differing levels of influence from perceived ease, perceived challenge, and non-parental family members. Brass, woodwind, and percussion students reported varying levels of influence from the people in their lives and perceived enjoyment. These survey results suggest that students are particularly influenced by their perception that an instrument will be fun to learn and play. To best engage this reported influence, band directors should present every instrument as fun, particularly those that may be underrepresented in the band
Mining Contamination of Legacy Deposits on Floodplains Along Turkey Creek, Western Border of the Ozark Highlands
No full textHistorical mining activities in the Tri State mining district in Southwest Missouri from 1850 to 1950 resulted in widespread metal contamination of stream sediments. Beginning in the 1840s, land disturbances associated with Euro-American settlement and agricultural expansion increased runoff and soil erosion rates resulting in the deposition of contaminated alluvium or legacy sediment on floodplains. This study assesses zinc (Zn) and lead (Pb) contaminated legacy deposits in cut-bank exposures along floodplains in Turkey Creek Watershed (119 km²) which drained mining areas in Missouri. Ore production histories were used date metal contamination profiles and calculate floodplain deposition rates in legacy deposits. Twelve sample reaches and 23 floodplain cores were collected from three mining sub-districts, in downstream order: Oronogo-Duenweg, Joplin; and Zincite. The average depth of Zn and Pb contamination was 1.8 m ranging from 0.3 to 2.8 m. Floodplain surfaces
Origin of Carbonate Mud Mounds in Southwestern Missouri
No full textSmall carbonate mud mounds are found in Lower Mississippian strata of southwestern Missouri. These compare favorably with larger mounds, known as Waulsortian mounds, located in the Meuse River valley of southern Belgium. The origin of Waulsortian and similar mounds is unknown, but they commonly are interpreted as accumulations of mud, where the presence of biological organisms responsible for supposed bio-construction remains uncertain. Alternative hypotheses are that these may have been non-cohesive slump or cohesive slide masses. Multiple techniques, including δ13C and δ18O isotopic analyses and unmanned aerial vehicle photography, were used to determine the most feasible working hypothesis. Determining the origin of the carbonate mounds will provide a key understanding of the geology of southwestern Missouri, and possibly the surrounding states
Characterization of the Interaction of Three Domains of NLRP2 (PYD, LRR, and NACHT) With EBP1 Protein
No full textNOD-like receptors (NLRs) are cytoplasmic proteins essential for various immune responses such as reactions to infectious diseases, metabolic and cellular damage, fetal development, and cancer. Among the 22 identified NLR proteins, research has highlighted the significant roles of NLRP2 in fetal development. NLRP2 is also classified as a maternal effect gene and the mutation to this gene can lead to DNA methylation imprinting defects, altered gene expression, and conditions such as recurrent miscarriages (RMs). The protein EBP1, which has been found to have roles in embryonic development has been implicated in the regulation of DNA methylation. Recent studies have also suggested that EBP1 could be a novel interacting partner of NLRP2. This has been observed through coimmunoprecipitation and Fluorescence Resonance Energy Transfer (FRET) techniques as well. In this research, I looked at the interaction between these two proteins in detail by examining which domains of NLRP2 are important for the interaction of this protein with EBP1. Thus, this study provides a detailed insight into possible mechanism by which EBP1 or other proteins could interact with NLRP2 and regulate DNA methylation
The Influence of Relational Frames on Climate Purchasing and Policy
No full textEvaluative conditioning refers to the effect that occurs when two stimuli are paired together, resulting in a change in the evaluation or function of one of the stimuli. Evaluative conditioning has been researched in various fields of study, such as advertisement and public administration, but synthetization efforts of these results with a relational frame theory approach, and vice versa, have been limited. This thesis used de-identified data from prior approved research to integrate and discusses two manuscripts that provide a relational frame theory perspective to evaluative conditioning effects. Study 1 extends a previous experiment by Matthews et al. (2022) through the use of a multidimensional scaling procedure in an attempt to model changes following a stimulus pairing observation procedure. Results from Study 1 show that participants formed pro-environmental relational classes following the training, as depicted by the MDS. These findings cohere with the changes in purchasing behavior as observed in Matthews et al. (2022). Study 2 also uses a multidimensional scaling procedure to extend previous research on evaluative conditioning in hypothetical policy adoption. Preliminary results from Study 2 show that trust in hypothetical policy does not change in the context of political branding but contextual cues are discussed for why this might be the case. Taken together, these translational studies have implications for teaching meaningful relational framing around climate action, as outlined in Study 1, but also for how policy proposals might be structured so that policy that supports environmental framing can be adopted
Population Viability of Egyptian Tortoises: Analyzing Demographics Sensitivities and Extinction Risk in North Sinai
No full textThis study investigated the population viability of the critically endangered Egyptian Tortoise (Testudo kleinmanni) across five populations in North Sinai, Egypt. The research aimed to assess demographic sensitivities, extinction risks, and the influence of environmental variables to guide conservation strategies. Using multistate mark-recapture models within a Bayesian framework, survival, transition, and recapture probabilities were estimated across life stages, integrating site-specific environmental data such as the Normalized Difference Vegetation Index (NDVI). The analysis revealed stark contrasts between populations, with three sites demonstrating high extinction risk due to lower juvenile survival and limited recruitment. In contrast, two populations exhibited demographic stability driven by higher survival rates and resilient recruitment. Population Viability Analysis identified female survival as the most critical factor for long-term stability, with elasticity analysis further emphasizing the importance of juvenile survival and transitions to adulthood. These findings underscore the ecological significance of habitat quality, with higher NDVI correlating positively with survival and productivity. Recommendations include habitat restoration, head-start programs for juveniles, and community-based conservation initiatives. This study highlights the urgent need for targeted, adaptive management to mitigate the ongoing threats of habitat degradation, climate variability, and human-induced pressures, offering an extensive framework for conserving this imperiled species
Microvascular Endothelial Permeability Coefficient Regulated by Purinergic P2Y2 Receptor
No full textInflammatory mediators profoundly affect endothelial permeability by disrupting its barrier function, resulting in increased permeability (hyperpermeability). Interestingly, hyperpermeability is involved in a wide range of disorders and diseases, and can pose significant risks to life in diseases, such as acute respiratory distress syndrome and systemic capillary leak syndrome. Though vascular leakage, a hallmark of inflammation, profoundly exacerbates the pathogenesis of diseases, the direct mechanism is not fully understood. In vivo study has shown that activation of nucleotide P2Y2 receptor (P2Y2R) increases permeability in murine venule. The goal of this study was to determine the molecular mechanism of P2Y2R-induced increase in permeability in primary cultured murine skeletal muscle microvascular endothelial cells (MSMEC). Wild type (WT) and P2Y2R knock out (KO) MSMEC were used to measure permeability response to P2Y2R agonist, uridine triphosphate (UTP, 10-5M), stimulation. Transwell permeability assay was used to measure endothelial permeability to fluorescence labeled-dextran (70 kDa). It was shown that the basal permeability in WT MSMEC was comparable to that in KO MSMEC, and unstimulated WT MSMEC responded similarly to UTP stimulated WT MSMEC. Normalized data from UTP-stimulated WT and KO MSMEC showed no significant difference in permeability over a time course. However, during the period between 30 and 90 minutes of UTP stimulation, there was a noticeable trend of increased permeability in WT MSMEC compared to KO MSMEC. Based on the results from current literature and our previous in vivo work, the undetected permeability response to UTP observed in this study may be attributed to the limited sensitivity of the macromolecule tracking approach using Transwell inserts, which may fail to capture transient changes in permeability upon initial stimulation with UTP in WT MSMEC. Identifying the mechanistic involvement of MSMEC P2Y2R in modulation of permeability will advance the understanding of vascular permeability during inflammatory response and contribute to the treatment of a wide range of diseases
Demographics and Recruitment Patterns in a Reintroduced Population of Alligator Snapping Turtles (Macrochelys Temminckii)
No full textReintroductions have increasingly become a useful tool for managing wildlife populations, but post-reintroduction studies to evaluate the success of these efforts are often lacking. In 2007, 265 Alligator Snapping Turtles (Macrochelys temminckii) were released into several semi-impounded wetlands in the Washita River drainage basin in southeastern Oklahoma, where surveys in the late 1990s suggested that the species was functionally extirpated. I conducted turtle trapping surveys using baited hoop nets to assess demographics and recruitment patterns in the population 11–12 years after the initial reintroduction. I estimated the age of juveniles by counting scute annuli and compared the data to previous records of turtles of known age for validation of the technique. I analyzed fecal materials to determine the dietary niche the species is occupying within the study system and compared it to published results from other populations. The diet data suggest that these turtles are functioning chiefly as benthic detritivores, indicating that individuals in my study population have a seemingly greater reliance on indiscriminate foraging than reported from other populations. I captured 75 M. temminckii, including 11 juveniles from naturally occurring nests that were hatched in captivity and subsequently released, and 15 juveniles I inferred hatched in situ. These data indicate at least limited successful reproduction by adults and survival of juveniles in the study population, despite evidence of high rates of depredation of naturally occurring nests in the study area