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Cover-crop Effects on Near-surface Soil Properties Over Time in the Lower Mississippi River Valley
Get PDFHuman population growth and climate change are present stressors that continue to put pressure on current agricultural production systems, where typical row-crop agricultural practices can negatively impact soil health. Extensive use of cover crops (CC) to increase soil health remains widely unrealized. Soil health in Arkansas is a major concern for sustaining agricultural output, therefore research into CC implementation across Arkansas to maintain or improve soil health is needed. The objective of this study was to evaluate the effects of CC (i.e., with and without CC) across various physical, hydraulic, biological, and chemical soil indicators in the Lower Mississippi River Valley over time. Averaged across depth, bulk density did not change over time under a no-cover-crop (NCC) treatment, but increased approximately 0.03 g cm-3 over time under CC. Averaged across CC treatment and aggregate size-class, water-stable aggregate (WSA) concentration differed by depth, with an increase over time of 0.012 g g-1 within the 0-5 cm depth interval. Total WSA (TWSA) concentrations differed between CC treatments over time, with TWSA concentrations increasing more under CC (0.054 g g-1) and did not change under NCC. Total WSA concentrations increased over time in the 0-5 cm soil depth (0.061 g g-1). Between Spring 2019 and 2020, reniform (Rotylenchulus spp.) and spiral (Helicotylenchus spp.) nematodes abundances differed between CC treatments, with an increase in population counts under CC (872 and 116, respectively), while populations did not change over time under NCC. Soil pH decreased over time under both CC (-0.3) and NCC (-0.2) treatments. Soil N content decreased over time under NCC (-22.6 kg ha-1), but did not change over time under CC. Results of this study emphasized the importance of the temporal nature of soil health as affected by CC and their potential to improve soil health in Arkansas
Development of a High-Throughput Screening Platform to Profile Gene Delivery and Transcriptional Control in Macrophages
Get PDFMacrophages are an important cell type in the body responsible for orchestrating the inflammatory response and return to homeostasis. Macrophages are often implicated in a multitude of disease pathologies including delayed wound healing, excessive fibrosis, autoimmune disease, and immunosuppression within the tumor microenvironment. Although macrophages have been targeted for therapeutic applications, success in utilizing them has remained elusive due to their relative ease of phenotype switching between inflammatory and anti-inflammatory. The challenge that remains is developing clinically relevant delivery vehicles that can target macrophages without causing a phenotypic switch counter-productive to the desired response. This is especially important when targeting regenerative processes. Alongside determining an appropriate delivery vehicle, it is necessary to determine the effects and utility of transcriptional modifiers in macrophages and the ability to target therapeutically relevant genes. This dissertation develops a high-throughput screening technique to determine inflammatory response experienced by macrophages in response to different clinically relevant delivery vehicles and establishes the ability to transcriptionally modify macrophages. In Chapter 2, we developed the inflammatory reporter and characterized the response experienced by RAW264.7 cells, a mouse macrophage cell line. Our results showed that the reporter expressed under NFκB response elements correlated with inflammatory markers and could be used as a sensitive and high-throughput screening technique for inflammatory response in macrophages. In Chapter 3, we used the inflammatory reporter to determine the inflammatory response to different viral and non-viral delivery vehicles and determined the inflammatory response and delivery efficiency of Adeno-associated virus (AAV) 1, 2, 5, 8, and 9, Adenovirus (Ad) 5/35, and non-viral delivery methods Lipofectamine 2000® and TransIT-X2®. We found that relatively, only AAV 1 and Ad5/35, which was designed for macrophage delivery, showed any increase in vehicle uptake with minimal inflammatory response while both non-viral delivery methods showed increased delivery and inflammatory response. In Chapter 4, we determined the ability to use catalytically dead CRISPR associated protein 9 (dCas9) fused with a proven transcriptional activator, VP64, to increase levels of interleukin 10 (IL-10) within RAW264.7 cells. This work in its entirety has developed a platform for quick and efficient screening of inflammatory responses experienced in macrophages and determined the ability to transcriptionally modify macrophages for therapeutic applications
A Grain of Hope: Analysis of The Economic Potential for an Association of South East Asian Nations (ASEAN) Rice Futures Market
Get PDFThe ASEAN (Association of Southeast Nations) region is the world\u27s leading rice producer, yet the region lacks a dedicated rice futures market. In contrast other world grain markets are served by liquid futures contracts, which aid producers through price discovery and risk management. This glaring gap raises a critical question: Can an ASEAN rice futures market be established to unlock the potential economic benefits for the region\u27s rice sector? By predicting ASEAN rice pricing features and analyzing the efficacy of hedging for regional rice market players, this study explores the viability of an ASEAN rice futures contract to service the ASEAN area. The study used a simulation architecture using the Thai 5% FOB rice price as a hypothetical futures contract price and prices from two other key ASEAN rice exporting and importing countries (Vietnam and Philippines) sourced from FAO GIEWS. A strong correlation between the hypothetical Thai 5% futures price and the other major ASEAN prices is a prerequisite for the success of a futures contract, which might be utilized as a risk management/hedging tool. Results show that Thai 5%, Vietnam 5%, and Philippines national average prices are highly correlated, indicating a futures contract based on Thai 5% rice has the potential to aid in risk management for Vietnamese exporters and Philippine importers. In addition, we identify a number of institutional and political challenges that would currently prevent the formulation of an ASEAN rice futures contract. Due to the absence of seasonality on the Thai5% price series, it does not make an attractive endeavor to basis trade; a necessary condition to attract more domestic market participants to enhance liquidity in the market. This analysis contributes significantly to ongoing discussions about regional agricultural cooperation and financialization efforts within ASEAN
Upcycling Imperfect Broccoli and Carrots into Healthy Snacks Using an Innovative 3D Food Printing Approach
Get PDFVegetables are healthy foods with nutritional benefits; however, nearly one-third of the world\u27s vegetables are lost each year, and some of the losses happen due to the imperfect shape of the vegetables. In this study, imperfect vegetables (i.e., broccoli and carrots) were upcycled into freeze-dried powders to improve their shelf-life before they were formed into food inks for 3D printing. The rheology of the food inks, color analysis of the uncooked and cooked designs, and texture analysis of the cooked designs were determined. The inks with 50% and 75% vegetables provided the best printability and shape fidelity. 3D printing at these conditions retained a volume comparable to the digital file (14.4 and 14.3 cm3 vs. 14.6 cm3, respectively). The control, a wheat flour-based formulation, showed the lowest level of stability after 3D printing. The viscosity results showed that all the food inks displayed shear-thinning behavior, with broccoli having the greatest effect on viscosity. There was a significant color difference between uncooked and cooked samples, as well as between different formulations. The hardness of the baked 3D-printed samples was affected by the type and content of vegetable powders, where carrot-based snacks were notably harder than snacks containing broccoli. Overall, the results show that 3D food printing can be potentially used to reduce the loss and waste of imperfect vegetables
Fast Fashion, Luxury Fashion, and Their Sustainability Efforts
Get PDFThe apparel industry can be divided into two categories: fast fashion and luxury fashion. It’s no secret that the apparel industry has a negative impact on our world in terms of sustainability, greenwashing, pollution, and human rights issues. Although the entire apparel industry plays a role in this, fast fashion seems to be at the forefront of these issues. It is necessary to understand the growth and consumer obsession with fast fashion to grasp its negative impact. In the same way, understanding the importance of luxury fashion to the consumer along with the strides being made by luxury fashion companies to combat the apparel industry’s lasting and detrimental impact on our environment will help to explain the industry dynamic. By conducting research comparing fast fashion and luxury fashion, vital information will be gained to call attention to this issue. To fully understand the comparable differences between fast fashion and luxury fashion, a specific comparison between the luxury fashion company Gucci and the fast fashion company SHEIN was conducted using tangible reports and available company information. To visually express the damage fast fashion has on the environment, a creative advertisement campaign was created. This advertisement campaign, in theory, was meant to be from a luxury fashion company urging a fast fashion company to become more sustainable. This research and information are meant to serve as benchmarks for further research and will allow awareness and attention to be brought to the issue while explaining and addressing two vital components in the apparel industry
Books as Bridges: Utilizing Multicultural Literature to Foster Connection, Representation, and Inclusivity in Student Education
Get PDFBackground: Linguistic and demographic diversity is growing in classrooms across the United States however teacher demographics remain overwhelmingly composed of monolingual white women. There is great need for a bridge between cultures that honors and empowers diverse experiences. Through personal and professional experiences, I have witnessed the power of crossing cultural bridges through literature. Purpose: This study investigates the role of multicultural literature as a powerful tool to bridge cultural divides, provide authentic representation for marginalized groups, and cultivate a sense of belonging among students from various backgrounds. Methodology: This study reviewed peer-reviewed sources to gather insights into the effectiveness of multicultural literature in student education. Each source is peer reviewed and from reputable journals such as the Journal of Teacher Education. The literature identifies effective strategies for selecting, implementing, and evaluating multicultural texts in diverse educational settings. In addition to peer-reviewed literature, 40 children’s books have been reviewed and analyzed for components of quality multicultural literature. Results: Multicultural literature creates a bridge between teachers and students of different backgrounds enhancing connection and exposure to various cultures. Through a comprehensive examination of existing literature, this review synthesizes key findings on the benefits and challenges of incorporating multicultural literature into common teaching practices such as read alouds. Ultimately, this literature review contributes to a deeper understanding of the potential of books as bridges for fostering connection, representation, and inclusivity in student education. Discussion: By shedding light on the significance of diverse narratives in shaping students\u27 identities, perspectives, and understanding of social issues, this study highlights the importance of integrating multicultural literature as a cornerstone of culturally responsive teaching. Furthermore, the use of multicultural literature lends itself to the incorporation of Collaborative for Academic Social Emotional Learning (CASEL) components thus furthering students’ personal development through social emotional learning. Finally, it is crucial that the utilization of multicultural literature be deliberate and mindful, as certain texts have the potential to perpetuate stereotypes and inaccurately portray marginalized communities
Current Trends and Experiences from a Contract Research Organization Perspective
Get PDFThe primary goal of this presentation is to provide an update on the trends of research observed at a contract research organization (CRO) in recent years as it relates to species, study design type and products tested, as well as, challenge models used and products that have shown benefits in various study designs. The information in the presentation is based off of studies conducted from 2014-2024 at one CRO, Colorado Quality Research (CQR), and represents the experiences at CQR. Many of the parameters discussed will be from 2014-2019 and 2020-2024 to observe trends from over 5 years ago and more recent trends in the past few years
A Versatile, Semi-Automated Image Analysis Workflow for Time-Lapse Camera Trap Image Classification
Get PDFCamera traps are a powerful, practical, and non-invasive method used widely to monitor animal communities and evaluate management actions. However, camera trap arrays can generate thousands to millions of images that require significant time and effort to review. Computer vision has emerged as a tool to accelerate this image review process. We propose a multi-step, semi-automated workflow which takes advantage of site-specific and generalizable models to improve detections and consists of (1) automatically identifying and removing low-quality images in parallel with classification into animals, humans, vehicles, and empty, (2) automatically cropping objects from images and classifying them (rock, bait, empty, and species), and (3) manually inspecting a subset of images. We trained and evaluated this approach using 548,627 images from 46 cameras in two regions of the Arctic: “Finnmark” (Finnmark County, Norway) and “Yamal” (Yamalo-Nenets Autonomous District, Russia). The automated steps yield image classification accuracies of 92% and 90% for the Finnmark and Yamal sets, respectively, reducing the number of images that required manual inspection to 9.2% of the Finnmark set and 3.9% of the Yamal set. The amount of time invested in developing models would be offset by the time saved from automation after 960 thousand images have been processed. Researchers can modify this multi-step process to develop their own site-specific models and meet other needs for monitoring and surveying wildlife, balancing the acceptable levels of false negatives and positives