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A Tale of Two Law Schools
Full text linkOn the august occasion of the 100th anniversary of the University of Arkansas School of Law, this Essay celebrates one of its singular achievements: the decision of then-Dean Robert Leflar to admit Silas Herbert Hunt, the first African American allowed to enroll for graduate or professional studies at any all-white university in the former Confederacy since reconstruction. The bravery of both Leflar and Hunt has been correctly celebrated in the past, but this Essay seeks to highlight why it was actually braver than one might think (for both Hunt and Leflar) by comparing the actions of Arkansas Law with the shameful and illegal actions of the University of Tennessee College of Law (an institution that I love enough to hold responsible for its past). My colleague Briana Rosenbaum has aptly described the University of Tennessee’s approach to desegregation as “[d]eflect, [d]elay, [and] [d]eny.
Blackberry Plant Named ‘A-2718T’
Full text linkDescription and specifications of a new and distinct blackberry cultivar named ‘A-2718T’ which originated from seed produced by a hand-pollinated cross ‘A-2487T’ (a non-patented, unreleased genotype) × ‘A-2418T’ (a non-patented, unreleased genotype). This new blackberry cultivar can be distinguished by its medium to large fruit size, firm berries, excellent crop, late season ripening, and good plant health
Rice Cultivar ‘Taurus’
Full text linkA rice cultivar designated Taurus is disclosed herein. The present invention provides seeds, plants, and plant parts derived from rice cultivar Taurus. Further, it provides methods for producing a rice plant by crossing Taurus with itself or another rice variety. The invention also encompasses any rice seeds, plants, and plant parts produced by the methods disclosed herein, including those in which additional traits have been transferred into Taurus through the introduction of a transgene or by breeding Taurus with another rice cultivar
This Land is Your Land, This Land is My Land: The Keys to Unlocking Eight Million Acres of Checkerboarded Public Land
Full text linkThe term “checkerboarded land” has become associated with alternating public and private square-mile lots in Western states such as Wyoming, Colorado, Washington, Idaho, Montana, Utah, Nevada, and Arizona. In the mid-19th century, the United States was in the throes of Manifest Destiny. President Abraham Lincoln signed the 1862 Pacific Railway Act which aimed to connect the eastern United States with the newly acquired western territories by developing the Transcontinental Railroad. As an incentive for building the rail line, the federal government granted the even-numbered one-square-mile sections of land to the railroad companies, while retaining the odd-numbered one-square-mile sections for itself. The Federal Land & Management Act of 1976 makes public land, specifically land managed by the Bureau of Land Management (BLM), accessible to the public for recreation. Of the 2.4 billion acres of land in the United States, the BLM manages over 240 million surface acres and roughly 60% is privately owned.
Before analyzing the legal problems and recent developments on checkerboarded land, it is essential to understand how these sections of land came to be and why they exist in this way. Section II will briefly discuss the history of the property landscape and the conflicting interests of private landownership versus publicly accessible land. It will then delve into the landmark case of Iron Bar Holdings, LLC. v. Cape, a case of first impression that may be the first of many corner-crossing cases. Subsequently, I will address some of the primary conflicting interests in this decision and the key legal principles undermining this area of the law. Following that, I will discuss outcomes from the case, outlining the current state of the law and identifying its pitfalls. In Section III, I will then explore where the law should progress and offer solutions to resolve the problem of checkerboarded lands
Nanoparticle Iron Based Catalysts for Clean Water and Other Applications
No full textThis dissertation explores the development, characterization, and application of iron-based catalysts for environmental remediation and energy generation. The research focuses on Fe-based nanomaterials for water purification, electrochemical ammonia production, and ethanol oxidation enhancement. The first section of the dissertation investigates the removal of water contaminants using nickel-iron (NiFe) bimetallic nanoparticles. Various NiFe ratios were synthesized and tested for their efficiency in degrading the azo dye (Orange G), with lower Ni content formulations achieving 80–99% dye removal within 60 minutes. Results show that changing the molar ratio of nickel to iron caused different removal rates, as well as the extent of overall elimination of azo dye from water. NiFe alloy nanoparticles were stabilized onto 5 different supports – two commercially available activated carbons and three custom synthesized heteropolyacid functionalized carbon. The carbons did not show an enhancement in dye removal until at the higher 100 gram starting concentration. Post-reaction characterization indicated the structurally disordered catalyst lost the metal at the surface oxidation occurred resulting in oxide and hydroxide presence for Fe and Ni to increase. The study was expanded to the degradation of energetic compounds, specifically TNT and RDX, using Fe(III)-embedded covalent organic frameworks (COFs). A mechanochemical synthesis approach allowed a 10× scale-up of COF production, improving yield efficiency from below 10% to 75%. Fluorescence-based detection enabled the sensitive quantification of TNT and RDX down to 1–4 µg/mL, while sequestration experiments demonstrated 90% TNT and 85% RDX removal within 30 minutes. Additional research focused on the application of Fe-COFs for nutrient and per- and polyfluoroalkyl substance (PFAS) removal. Adsorption studies demonstrated no selectivity for nitrate and phosphate, with Fe-functionalized supports underperforming conventional adsorbents. Electrochemical degradation pathways for PFAS were explored due to the slow adsorption rate for the COFs. The second section of this dissertation examines the role of Fe in electrocatalysis for sustainable energy applications. Ethanol oxidation reaction (EOR) behavior was tested using PtRhNi catalysts in Fe-doped electrolyte solutions. Fe incorporation was shown to increase current density by facilitating hydroxyl radical formation to cleave the C–C bond. This improvement resulted in more efficient ethanol oxidation with greater selectivity toward CO₂ production. Another avenue of research focused on electrochemical nitrogen reduction to ammonia (NRR) as a sustainable alternative to the Haber-Bosch process. However, rigorous control experiments revealed significant ammonia contamination, which compromised reported yields. Experiments were plagued with low production rates and faradaic efficiencies pointing to the need for improved catalyst selectivity. Further studies attempted to enhance NRR selectivity by functionalizing FeNi catalysts with thiol ligands, but results showed no effective binding, prompting a shift toward computational modeling and alternative ligand strategies. A comprehensive review of heterogeneous catalysts for NRR identified Fe-based catalysts with sulfur ligands as promising candidates for enhancing selectivity and reducing hydrogen evolution competition. Overall, this work advances the understanding of Fe-based catalysts for environmental and energy applications. The findings emphasize the need for further optimization in reaction kinetics, catalyst stability, and selectivity to enable large-scale deployment in water treatment and sustainable energy systems
Understanding Glufosinate Resistance in Palmer Amaranth and Examination of Additives for Improved Weed Control
No full textThe aim of this dissertation was to: 1) provide an in-depth review about the potential use of natural and synthetic glutathione S-transferase (GST) inhibitors to enhance herbicidal activity or induce crop safety; 2) determine if the addition of metabolic inhibitors to glufosinate is an effective approach to enhance weed control; 3) investigate the mechanism conferring resistance to glufosinate in a highly-resistant Palmer amaranth accession; 4) characterize the genomic rearrangement involved in glutamine synthetase 2 amplification in a Palmer amaranth accession resistant to both glufosinate and glyphosate; 5) quantify the distribution of glufosinate resistance among Palmer amaranth accessions within a 15-km radius surrounding the glufosinate-resistant Palmer amaranth accession initially collected in 2020; 6) determine the postemergence resistance profile of glufosinate-resistant Palmer amaranth accession and identify effective herbicides to control it under field conditions; and 7) evaluate different herbicide programs and the presence of residual herbicides in soybean to control seven-way herbicide-resistant Palmer amaranth accession. Several GST inhibitors have the potential to increase efficacy when mixed with herbicides. However, further research is needed, particularly in vivo experiments. A formulated premixture of glufosinate with the plant-derived flavonoid baicalin enhanced weed control. The amplification and overexpression of the chloroplastic glutamine synthetase (GS2; enzyme targeted by glufosinate) was characterized as one of the resistance mechanisms conferring glufosinate resistance in Palmer amaranth. Extrachromosomal circular DNAs (eccDNAs) were identified as the cause of this increase in GS2. The eccDNA structure co-duplicated 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which is the enzyme targeted by glyphosate, along with the increase in GS2. Palmer amaranth accessions collected in 2023 were capable of surviving glufosinate applications, and the presence of GS2 amplification was observed in crop fields near the location where the 2020 sample was originally collected, suggesting that glufosinate resistance is present in more areas than initially detected. This result is alarming due to the resistance profile also observed in this accession. Additional investigations with the initial glufosinate-resistant accession revealed the presence of seven-way resistance to postemergence herbicides from groups 2, 4, 5, 9, 10, 14, and 27 (Weed Science Society of America/Herbicide Resistance Action Committee). Field experiments showed that this accession was more likely controlled by preemergence than postemergence herbicide chemistries. A high level of control of the seven-way resistant accession was achievable when residual herbicides were applied sequentially with 2,4-D or dicamba. However, not all plants were controlled, and a zero-tolerance approach should be employed to avoid seed deposition into soil seedbank
A Mobility Data-Driven Approach to Analyzing and Modeling Park Accessibility Inequities and Use in U.S. Cities
No full textUrban Park accessibility inequities have been a longstanding issue globally and the United States in particular. Despite the benefits that urban parks provide, use and access is not equitably distributed among the population, often favoring historically privileged populations over others (disadvantaged). Fortunately, improvements have been made in recent years to promote balanced park distribution in some cities; however, evidence still shows that most cities are behind. Interestingly, the rise in human mobility data has facilitated the study of human behavior and use of activity spaces. This thesis advances the existing studies on park accessibility and emerging human mobility to study park accessibility inequities in American cities in an integrated fashion. The objectives are clearly defined to analyze city-wide patterns in park visitation and empirically uncover the influence of socioeconomic and demographic factors by highlighting observed disparities that perpetuate long-term inequities in park accessibility. Additionally, the study aims to model dynamic visitation patterns, considering the evidence and trends in current accessibility. The important theoretical, methodological, and contextual knowledge gained in this study could greatly benefit decision-makers, and the recommendations are particularly useful to urban planners, city administrators and managers, and private businesses seeking to find better ways to eradicate inequities, foster balanced use/access to public parks, and promote inclusive cities for all Americans
Estimating Drivers of Certified Seed Adoption Among Colombian Rice Producers and Assessing Yield Impacts at the Plot Level
No full textAs the population rises, there is a growing need to increase agricultural productivity to keep up with food demands. However, agricultural land expansion to increase production is not a sustainable solution long-term. The Global South particularly faces greater needs for rice as a staple food, yet countries in Latin America like Colombia have faced declining rice yields. Technologies that boost agricultural productivity using existing land, such as certified seeds, are considered a tool to address this problem in the face of land scarcity and climate change. Certified seeds have high genetic purity and are free from disease. Despite the quality of these seeds, adoption rates in Colombia have been low (36% in 2021), although it is Latin America’s third largest rice producer. Colombia has high per capita rice consumption compared to neighboring countries at 43 kg annually, and the Colombian rice sector is seeking to increase its competitiveness as it opens its rice market through trade integration. One of the ways the rice sector is seeking to increase yields is through the promotion of certified seeds. Reasons for low adoption have not been widely studied in the region in spite of evidence of low adoption rates. Using a producer survey, this study assesses factors that positively or negatively influence certified seed adoption in the Tolima department of Colombia to understand how to enhance technology usage. A total of 353 responses provide information about rice production practices and yields in 2023, as well as socioeconomic information about farming households. Assessment is conducted at the plot level to improve the accuracy of analysis by accounting for any plot-level differences influencing adoption. An OLS model serves as a baseline, while three methods that control for endogeneity provide a more nuanced understanding of adoption effects: a control function approach, endogenous switching regression, and a copula switching regression. A control function regression is used to understand adoption interactions, and an endogenous switching regression model is used to assess drivers of adoption, as well as yield outcomes among adopters and non-adopters. Yield impacts are quantified to understand the outcomes of the adoption decision, which could be useful in promoting adoption. Results indicate that the combination of adoption with other variables has a significant impact on yields. Crop rotation, farm size, area harvested, negative weather events, and extension significantly influence yields, depending on adoption status. The drivers of adoption are farm size, seed cost, and the involvement of women in decision-making, while credit is negatively associated with adoption. Treatment effects indicate that adoption leads to a 1.5 tons/ha yield gain for adopters, and if non-adopters were to use certified seeds, their yields gains would be 0.6 tons/ha. Insights have implications for technology adoption in Colombia and other rice-producing countries to enhance the global rice supply and keep up with food demands
Synthesis and Characterization of Polymer-Coated Metal Nanostructures and Gelatin-Incorporated Hydrogels for Biomedical Use
No full textThe development of advanced materials for disease management and treatment presents a pressing challenge in the health sector. The overall objective of this research is to contribute to the development of advanced materials with tailored properties for biomedical applications, with a focus on cost-effective and robust nanoparticles and biomaterials. The first part of this work focuses on designing and synthesizing earth-abundant copper nanoparticles with desired optical properties. Copper nanoparticles, which provide a more affordable alternative to gold and silver, are being investigated due to their unique plasmonic properties. However, their susceptibility to oxidation limits their application. To address this challenge, copper nanoparticles are being surface-functionalized with polymers such as methoxy polyethylene glycol acetic acid (PEG-COOH) and polydopamine (PDA) to enhance their stability in different environments. Thorough investigations of the stability of PEG-COOH and PDA coated copper nanoparticles were carried out in aqueous solutions. Such a surface-modification method can be applied to other non-precious metals and metal oxides to improve their stability in various applications. In addition to nanoparticle research, the second part of this work aims to develop a gelatin-incorporated hydrogel for sustained protein delivery over 5-10 days for chronic wound healing. Building on our previous work with polyethylene glycol-based anionic injectable hydrogels, which showed improved release of human acidic fibroblast growth factor (hFGF) in vitro, gelatin is being incorporated to enhance the biodegradability and performance of the hydrogel. Gelatin, a natural polymer derived from collagen, possesses non-toxic, biocompatible, and bioadhesive properties, making it an ideal component for wound healing. Gelatin A or Gelatin B was incorporated into the formulations to improve the controlled release of hFGF and its mutants while maintaining the rheological properties of the hydrogel suited for wound healing applications
The Fate of Intra- and Extracellular Antibiotic Resistance Genes Through Advanced Wastewater Treatment Process
No full textMore areas across the globe are becoming affected by water stress or water scarcity. The decrease in available freshwater due to overconsumption reveals the direct need to consider other sources for necessities such as drinking water or food production. Agricultural irrigation uses 70% of the world’s freshwater, making the focus on safe and reliable reclaimed water for agricultural reuse imperative. However, contaminants of emerging concern (CECs), such as antibiotics and their resulting antibiotic resistance genes (ARGs), can spread and affect human health if reclaimed water is not treated to the proper level. Antibiotics are widely used in human medicine and animal husbandry, developing into the problem of antibiotic resistance. ARGs can multiply throughout the environment via vertical or horizontal gene transfer (HGT) and can be present as intra- or extracellular DNA (iDNA and eDNA, respectively). eDNA can bind to sediment and particulate matter, shielding it from possible degradation and inactivation by wastewater treatment plant (WWTP) processes. WWTPs are typically unable to target and remove eARGs; however, advanced treatment processes for reclaimed water may be able to remove them. This study measured ARGs in various environmental samples, including lakes, ponds and wastewater treatment facilities with a pilot advanced treatment train. Five ARGs corresponding with resistance to different antibiotic classes (tetracyclines, sulfonamides, and macrolides) were quantified using qPCR. Different levels of ARGs were detected in all samples collected. A separation protocol was also tested for iDNA and eDNA in water samples by investigating the recovery efficiency of each. However, results from this study showed that the proposed separation protocol has a low recovery efficiency for eDNA, and that more research on iDNA and eDNA separation is needed in the future. Moreover, the advanced treatment processes in the pilot facility exhibited inconsistent ARG removal rates at all ozone dosages tested, which is most likely attributed to the differences in individual ARG structures, as well as the sequence of advanced treatment processes