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2. Assignment One: U.S. Voting Rights Character Card Assignment With Presentation
No full textThis assignment requires students to think like curators and research their assigned historical figures. Figures are tied to the women’s suffrage and anti-suffrage movements in the United States. Museums and historic landmarks want visitors to engage in history and to consider the complicated, interesting backgrounds of figures who acted in unique ways, shaped by their notions of class, race, gender, culture, power, education, religion, democracy, and citizenship. Often, museums ask their visitors to imagine they are historical figures. One way to achieve this is by providing wearable lanyards with character cards that feature an image of a historical figure on one side and biographical information tied to a theme on the other. The idea is that visitors view the world through their character’s eyes. For this assignment, research your figure and create such a card
Evolution of teachers’ perspectives on family engagement: Building dual capacity for multilingual learners
Get PDFFamily engagement in multilingual learner education offers benefits associated with improved academic performance, stronger parent-teacher communication, and more inclusivity of cultural and linguistic diversity. Responding to calls for professional development that enables teachers to meaningfully involve families, this paper draws from surveys and course assignments to examine how teachers expanded their perceptions about the incorporation of multilingual learner families in a graduate program. We conclude by discussing implications for teacher professional development with specific attention to how teachers can integrate multilingual learner families
White Paper: Addressing Nature Access Inequities Through School-Based Interventions in Early Childhood Education
Get PDFAccess to nature is a powerful determinant of young children’s physical, mental, and cognitive development. Yet systemic barriers, particularly those related to geography, race, and socioeconomic status, prevent many young learners from engaging meaningfully with the natural world. Urban, rural, and low-income communities face distinct but compounding challenges in accessing quality green spaces. In light of these disparities, early childhood settings such as preschools, Head Start programs, and childcare centers, play a pivotal role in offering equitable nature access during the school day. This white paper makes the case for nature-based experiences in early learning environments as a vital solution to close the green equity gap
Post-Harvest Storage of Fuzzy Cottonseed: Quality, Airflow Modeling, and Energy Use
No full textFuzzy cottonseed is a valuable byproduct of the cotton ginning process. When cottonseed exits the cotton gin, it often retains high temperatures and moisture contents. Once in a storage facility, the cottonseed needs to be conditioned for safe storage. The overall objectives of this study were to analyze quality changes in cottonseed according to storage conditions, determine the airflow resistance properties of fuzzy cottonseed, develop a computational fluid dynamics (CFD) model of a representative cottonseed storage facility, and analyze cottonseed aeration fan strategies, runtimes, and costs. Changes in quality dictate the allowable storage time for cottonseed and are impacted by temperature and moisture content. For the cottonseed quality test, samples of cottonseed were stored at 8%, 10%, 12%, 14%, and 16% w.b. moisture content, temperatures of 7.2° C and 22° C, and storage durations of 3 months, 6 months, and 9 months. Results of this study indicate that at higher temperatures and moisture contents greater than 12% w.b., cottonseed incurred a significant increase in free fatty acid (FFA), a significant reduction in oil content, and a significant reduction in grade. Low temperatures (7.2° C) and moisture contents of 8 to 10% w.b. retained good seed quality characteristics. Improved knowledge of airflow through cottonseed may improve conditioning techniques and guide senor placement for monitoring systems. For the CFD study, airflow resistance coefficients of cottonseed stored at a density of 400 kg/m3 was experimentally determined. These laboratory tests utilized an airflow chamber to vary airflow velocity and measure pressure drops between two points in the seed pile. Power law resistance coefficients were determined to be C0 = 34960.27 and C1 = 0.68843. The CFD airflow model was constructed using a solid model of a cottonseed storage facility, which was input to a Finite Volume CFD solver. Operating conditions and airflows were measured at the model warehouse. The final CFD model produced an airflow velocity contour map of the storage facility, indicating several “dead zones,” areas with low airflow velocities. Uniformity and dead zones were analyzed at the 1m, 3m, 5m, and 7m levels from the floor of the seed pile. Uniformity ranged from 64% at 1m to 85% at 7m. Notable dead zones occurred at the 1m, 3m, and 5m levels and ranged from 1.18% to 1.86% of the plane area (7m2 to 12m2). The final objective analyzed energy use in cottonseed storage, for three storage warehouses with different seed pile depths, target airflow rates, and two different climates. Also presented in this study were three common aeration strategies and a basic heat balance calculation, which shows the minimum aeration time to achieve seed pile temperatures less than 15.6° C. This study gave a wide range of expected fan runtimes and cooling costs, which ranged from 0.132 to 2.094 hours of aeration and from 3.61 per Mt conditioned. This range of costs corresponded to 0.08% to 2.00% of crop value at the time of sale
Criminal Behavior Responses to Changing Penalties: Estimating the Impact of Felony Theft Threshold Changes
Get PDFThis study estimates how criminal behavior changes in response to shifts in felony theft thresholds, contributing to broader evidence on the deterrent effects of criminal penalties. Using detailed incident-level crime reports, this study applies econometric techniques to evaluate how offenders responded to reduced penalties. Analyzed within is California’s Proposition 47, which raised the felony threshold for theft-related offenses from 950. The results show a significant increase in low-level shoplifting (approximately 21%) and more substantial rises (approximately 24% to 30%) in crimes within the threshold overlap (950). Additionally, the value stolen in crimes below the $450 threshold increased by approximately 10%, indicating offenders’ strategic responses to reduced penalties—particularly where information about the stolen items’ value is readily accessible. Theft incidents demonstrated minimal changes, with coefficients being sensitive to methodology and insignificant both statistically and in magnitude. The analysis also identifies several systematic police misclassifications, which present challenges in accurately measuring crime impacts. These findings demonstrate that changes in legal penalties can shape offender decision-making, particularly when thresholds are well-known and enforceable, and highlight the need for careful consideration of incentives, enforcement accuracy, and information completeness in criminal justice reform
A Comparative Study of Land Use Regulations and Impact on Coastal Estuaries
No full textThe study presents a mixed method and longitudinal assessment of land cover change, estuarine land loss, and policy implemented to address the past and anticipated estuarine losses in the Cooper River and North and South Santee watershed over the past twenty years. This study uses National Land Cover Dataset from 2001 to 2021, NOAA’s SLR projection data and planning documents from 1990 to 2025 to examine policy evolution among ten major themes. The results illustrate significant changes in land cover, notably the transition of wetlands, agriculture, and forests to developed land, as well as an evident spike in the integration of planning themes over time, particularly between 2002-2021. Still, planning and theme integration exhibit geographical discrepancies between South Carolina\u27s urban and rural coastal areas, with urban areas using more planning documents and tools, while rural areas have fewer resources and less capacity. Recommendations are given to each watershed, with a focus on climate adaptation, low-impact development, nature-based infrastructure, interjurisdictional collaborations and wetlands protection. This research concludes that ensuring watershed and ecosystem resilience in the face of increasing development and SLR requires adaptable and tailored planning approaches based on actual land cover and ecological patterns and distinct risk levels of each watershe
Discovery of High-Performance Cathode Materials for Protonic Ceramic Fuel Cells
No full textEnvironmental pollution and rapid energy consumption have become common problems in global development and will continue to grow with the world population. PCFCs use proton-conducting ceramics as electrolytes, with low activation energy and high ionic conductivity at intermediate temperatures, enabling them to operate at intermediate-temperature conditions, which can effectively solve the problems of poor stability and high cost of exotic materials of traditional solid oxide fuel cells. However, as the operating temperature decreases, the electrocatalytic activity of the cathode decreases significantly, seriously affecting PCFC’s performance. Therefore, developing high-performance cathode material suitable for working under intermediate-temperature conditions has become the key to commercializing PCFCs.
This Ph.D. dissertation combines the synthesis of nanocomposites with ML-assisted material discovery methods to explore new cathode materials. In chapter two, the perovskite nanocomposite cathode of Pr0.3(Ba0.5Sr0.5)0.7Co0.8Fe0.2O3−δ was designed, fabricated, and studied for its structure and electrochemical properties. Chapter three focuses on predicting new perovskite oxide materials with high hydrated proton concentration as a potential PCFC cathode material or a component of high-performance nanocomposite cathodes. The trained ML model predicted the HPC values of two unknown perovskite materials for verification. The predicted value is very close to the true value. Chapter four focuses on predicting perovskite oxide materials with low area-specific resistance to serve as another component of nanocomposite cathodes. With the help of the well-trained model, ASR values of unknown perovskite materials were predicted for verification. The overall results show that the model has an important reference value in trend judgment and preliminary material screening
Elucidating the Mechanisms Underlying a Functional Plant-Arbuscular Mycorrhizal Symbiosis Using Omics Approaches
No full textArbuscular mycorrhizal fungi (AMF) are obligate biotrophs forming symbiotic association with plants. The plant-AMF symbiosis has gained much attention due to its ability to improve plant nutrient uptake, especially phosphorus, which is often inadequately available to plants due to its limited mobility and complex formation in many soils. Phosphorus (P) is a crucial nutrient for plants, and most phosphate fertilizers are derived from phosphate rock, a finite natural resource. Thus, optimizing P uptake is vital for sustaining crop yields and addressing the needs of a growing global population. Plant-AMF symbioses are significant in this context, as AMF can acquire P from phosphorus-limited soils through their extensive hyphae. In exchange, plants supply carbon to promote AMF growth, establishing a mutually beneficial symbiotic association. However, various factors, including the species of plants and AMF, along with the environmental conditions under which the symbiosis occurs, can affect the effectiveness of this symbiosis. Therefore, understanding the biotic and abiotic factors that influence the symbiotic efficiency is essential for designing effective management strategies for using AMF in agroecosystems.
This dissertation investigates the primary drivers affecting the plant-AMF symbiosis by probing the molecular cross-talk between plants, AMF, and the surrounding soil microbiome in phosphorus-limited settings. The first objective was to evaluate how various sorghum genotypes, differing in their inherent root traits that affect P acquisition efficiency (biotic factor), and the stratified nutrient availability (an abiotic factor), impact plant-AMF symbiotic efficiency and hence the outcome of this symbiosis. A greenhouse experiment was conducted with multiple sorghum genotypes under stratified and uniform phosphorus conditions, both with and without AMF inoculation. The study examined the trade-offs among different phosphorus-acquisition strategies (root growth, root metabolite production, and mycorrhizal symbiosis) and the resulting changes in root metabolomes. The results indicated that AMF treatments altered phosphorus-acquisition strategies irrespective of the plant genotype (whether P-efficient or P-inefficient). All sorghum accessions inoculated with AMF demonstrated greater tissue phosphorus content and shoot biomass than control plants without mycorrhiza. Furthermore, colonization by AMF influenced both the primary and specialized metabolite profiles in roots, as well as root morphology, facilitating a functional plant-AMF symbiosis. Notably, plants in stratified phosphorus environments benefited more from AMF colonization than those in uniform phosphorus conditions, highlighting the vital role of AMF in accessing localized phosphorus-rich areas. This observation is particularly pertinent given phosphorus\u27s low mobility and patchy distribution in most soils. Additionally, the influence of other soil microorganisms on phosphorus availability and AMF effectiveness led to further exploration of the broader soil microbiome.
Thus, the second study in this dissertation aimed to analyze the metabolite profiles from both roots and AMF hyphae, as well as examine the microbiome associated with plant roots (rhizosphere microbiome) and AMF hyphae (hyphal microbiome). For this research, a greenhouse mesocosm experiment using sorghum genotypes with varying root exudate profiles was established, with either Rhizophagus intraradices, Gigaspora margarita, or an uninoculated control (non-mycorrhizal). The experiment setup included separate compartments for roots and hyphae to assess how plant and fungal exudates affect microbiome composition. The goal was to determine how various combinations of AMF species and host genotypes shape the hyphal microbiome and affect symbiotic performance. The findings demonstrated that the soil metabolite profiles of the AMF and the plant root compartments differed. The bacterial communities were also different in the hyphosphere and rhizosphere compartments. It was also noted that AMF-inoculated plant roots selectively attracted mycorrhizal helper bacteria, potentially enhancing the symbiotic efficiency. These findings emphasize the critical role of soil microbial communities in enhancing AMF-mediated nutrient uptake and their significance in the success of plant-AMF partnerships.
The third and final study of this dissertation examined lipid dynamics within the plant-AMF symbiosis, an area of increasing interest following recent discoveries that AMF are lipid auxotrophs depending on their host plants for lipid supply. By using root and hyphae samples from the same greenhouse mesocosm experiment described earlier, lipidomic analyses were performed to assess the impact of symbiotic relationships between three different sorghum genotypes and two AMF species (R. intraradices and G. margarita), including a non-inoculated control, on lipid composition. The results showed variability in lipid profiles associated with different AMF species. R. intraradices displayed broader upregulation of lipid species across both roots and hyphae, indicating a more metabolically active interaction. Both AMF species had higher abundance of storage lipids such as triglycerides and diglycerides, indicating a higher carbon requirement for extensive hyphal growth and spore production. The roots and hyphae showed distinct lipid profiles, with AMF-inoculated roots exhibiting a higher abundance of several lipid species not observed in non-inoculated control roots. These findings reveal the functional diversity in lipid accumulation among various AMF species and underscore the importance of lipids in mediating plant-AMF symbiosis.
In conclusion, this dissertation enhances our understanding of the plant-AMF symbiosis by offering important insights into the complex interactions among host plants, AMF species, and soil microbial communities under limited P availability