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Anthocyanin Extraction Methods: Synthesis of Morpho-Anatomical Knowledge for Decision-Making Based on Decision-Tree
Get PDFEfficient anthocyanin extraction from emerging food matrices is essential in food technology and requires a precise, consistent, and clear extraction method. This study aimed to develop a decision-tree tool for selecting the optimal anthocyanin extraction technique. A comprehensive data synthesis covering the years 2018 to 2023 was conducted using leading academic databases, including Web of Science, Scopus, Medline, and SciELO. A combination of systematic and non-systematic approaches was employed to guide the decision-making process. The keywords used included “anthocyanin extraction methods,” and studies with more than 10 citations were prioritized, along with recent and relevant publications. Thirty-six articles were analyzed according to the PRISMA 2020 guidelines for systematic reviews. While ultrasound and microwave-assisted methods were predominantly featured, accounting for 46% of the reviewed studies, other methods such as enzyme-assisted extraction, deep eutectic solvents, and ionic liquid extraction were also evaluated for their comparative efficiency and suitability across various matrices. Fruits were the primary matrix, with a focus on the pericarp. While fruits, particularly the pericarp, was the primary matrix studied, the decision-tree tool is designed to be applicable across various food matrices, demonstrating its versatility and generalizability beyond fruits. The decision-tree tool was successfully applied to matrices with different structures, showcasing its adaptability. Integration of this tool could streamline selection processes, resulting in significant time and resource savings. In conclusion, this study highlights the influence of plant morpho-anatomical structures and extraction parameters on anthocyanin yield. It demonstrates how the decision-tree approach enhances efficiency and productivity, validated through blackberry and purple sweet potato matrices
Immersive Virtual Reality-Based Learning as a Supplement for Biomedical Engineering Labs: Challenges Faced and Lessons Learned
Get PDFIntroduction: Immersive virtual reality (VR) based laboratory demonstrations have been gaining traction in STEM education as they can provide virtual hands-on experience. VR can also facilitate experiential and visual learning and enhanced retention. However, several optimizations of the implementation, in-depth analyses of advantages and trade-offs of the technology, and assessment of receptivity of modern techniques in STEM education are required to ensure better utilization of VR-based labs.
Methods: In this study, we developed VR-based demonstrations for a biomolecular engineering laboratory and assessed their effectiveness using surveys containing free responses and 5-point Likert scale-based questions. Insta360 Pro2 camera and Meta Quest 2 headsets were used in combination with an in-person lab. A cohort of 53 students watched the experimental demonstration on VR headsets in the lab after a brief lab overview in person and then performed the experiments in the lab.
Results: Only 28.29% of students reported experiencing some form of discomfort after using the advanced VR equipment as opposed to 63.63% of students from the previous cohort. About 40% of the students reported that VR eliminated or reduced auditory and visual distractions from the environment, the length of the videos was appropriate, and they received enough information to understand the tasks.
Discussion: The traditional lab method was found to be more suitable for explaining background information and lab concepts while the VR was found to be suitable for demonstrating lab procedures and tasks. Analyzing open-ended questions revealed several factors and recommendations to overcome the potential challenges and pitfalls of integrating VR with traditional modes of learning. This study provides key insights to help optimize the implementation of immersive VR to effectively supplement in-person learning experiences
A Multi-Tiered Mentoring Community Approach to Research Experiences for Local Students from Disadvantaged and Underrepresented Minority Backgrounds
Get PDFIntroduction: A research and mentoring program was developed to provide local first-generation students, students returning to school after a professional experience, and underrepresented minority students resources and relationships to guide them toward a STEM degree from a four-year university.
Methods: A multi-tiered mentoring community was formed including direct mentoring from graduate students and faculty advisors, peer mentoring among undergraduate students from different colleges and universities, and high school students to increase the accessibility of research opportunities for this demographic. Local students were recruited from Northwest Arkansas Community College and Upward Bound to combine community college and high school students in a novel manner. The programs were integrated whenever possible to emphasize peer mentoring, including mentoring lunches, research meetings, presentation sessions, conference presentations, and professional development mentoring sessions.
Results: On the post-program survey, students indicated the community formed in the program supported their STEM identity development, provided them with quality relationships, and developed skills valuable to completion of a STEM degree. This identity development was further evidenced by the students presenting their work at a conference and obtaining additional research positions after the summer program ended.
Conclusion: The post-program scores and continued efforts of different demographics of students to pursue STEM highlight the versatility of the multi-tiered mentoring community model to serve students from different ages, backgrounds, and demographics
Revolutionizing Kidney Care: Implementing Charged Separation Processes in an Artificial Kidney (2024)
Get PDFRevolutionizing Kidney Care: Implementing Charged Separation Processes in an Artificial Kidney
The 3MT (Three Minute Thesis) is a research communication competition that challenges students to communicate the significance of their projects without the use of props or industry jargon in just three minutes. The winner of the 3MT competition moves on to the Council of Southern Graduate School’s Regional Conference in March 2025.https://scholarworks.uark.edu/mtsturpc/1052/thumbnail.jp
Micro-Mechanical Characterization of UHPC Stiffness Mechanisms: Towards a Better Understanding of Concrete Elastic Modulus
Get PDFCurrent design code equations for estimating the elastic modulus of specialty concretes like ultra-high performance concrete are not all suitable. Developing empirical curves from exhaustive experimental testing is challenging for concretes that may have high levels of cement replacement with mineral admixtures and fibers at varying volume contents. As such, an alternative approach is taken that seeks to understand the constituent microscale stiffness mechanisms and relate the results to the macroscale. Micropillars are fabricated on several cement paste phases using a focused ion beam. A modified pico-indenter is used to determine the linear and non-linear behavior under micro-compression loading. Micropillar phases are determined by their chemical compositions, identified with an energy-dispersive X-ray. The compressive strength and stiffness of C-S-H, C-A-S-H, SF, CH, AFt/AFm, and a CH/C-S-H are provided in this study. With the stiffness of individual phases calculated and statistical curves developed, a novel homogenization scheme is proposed to combine cement paste phases. Considering phase stiffnesses as springs (in amounts consistent with phase volume fractions determined by X-ray powder diffraction) allows for them to be combined in series and parallel. Monte Carlo arrangement simulations are run in MATLAB. The same approach is used to homogenize UHPC (fibers, fine aggregate, and cement paste), and the code output is verified through initial experimental testing of cylinders. Cement paste homogenization through spring arrangement simulations proves to be an adequate approach. The code output falls within a 30% error when compared to two different hardened cement paste mixes, potentially within a 10% error if the upper portion of the bimodal distribution is considered outliers. However, when the UHPC homogenization is evaluated, the code fails to provide a reasonable estimation of the results
Generalizations of the Hardy Spaces and the Schwarz Boundary Value Problem
Get PDFWe prove that many of the boundary properties associated with functions in the classic holomorphic Hardy spaces on the complex unit disk are present in Hardy classes of solutions to certain nonhomogeneous Cauchy-Riemann equations and higher-order generalizations of these equations. Also, we explicitly solve generalizations of the Schwarz boundary value problem on the complex unit disk and the upper-half plane when the boundary condition is in terms of boundary values in the sense of distributions
Professional Development for Culturally Responsive Teaching: Examining the Relationship Between Self-Efficacy and Implementation in Teaching Practice
Get PDFThe purpose of this study sought to investigate the link between professional development and the implementation of professional learning to improve student performance. The purpose of this study was twofold. First, this study explored whether the professional development of culturally responsive teaching influenced classroom implementation. Second, this study examined the relationships between teachers’ implementation of culturally responsive strategies, teacher self-efficacy, and student performance. This approach (which contextualized academic knowledge and skills within a real-world setting) has been shown to lead to more meaningful experiences and increased interest in academic content (Gay, 2010; Ladson-Billings, 1995). The overarching questions that led this study were (1) How did professional development provided through Project SOAR influence teachers’ implementation of culturally responsive teaching practices?, (2) What is the relationship between teachers\u27 participation in Project SOAR and their perceived self-efficacy in implementing culturally responsive teaching?, and (3) What is the relationship between culturally responsive teaching implementation in the classroom and student performance? The methodology used in this study was a mixed methods approach, incorporating various research methods, such as a self-efficacy survey, classroom observation, and semi-structured interviews with participants to gather comprehensive data and insights. The study highlights the impact of Project SOAR TESOL on educators\u27 ability to implement culturally responsive teaching
Use of Google Earth Streetview to Evaluate Nesting by the Cliff Swallow (Petrochelidon pyrrhonota) in Lowlands of Eastern Arkansas, with Reports of New Records
Get PDFCliff Swallows (Petrochelidon pyrrhonota) typically construct their mud nests under the overhangs of cliffs. However, construction of concrete bridges and overpasses has provided suitable nesting structure in the last few decades. As the number of such nesting sites have increased, the breeding range also has expanded. We evaluated the use of Google Earth Streetview as a means of cheaply harvesting data regarding nesting distribution. The gourd-shaped nests of Cliff Swallows were easily discernible via available imagery, and we were able to document previously unreported nest sites of this species in 6 counties in eastern Arkansas (5 from imagery, 1 from physical survey). Benefits and limitations of this technique are discussed
Quantifying Marketing Lifts to Create a Data-Driven Model: Walmart Merchandising Operations Internship
Get PDFI assumed the role of a Merchandising Operations Intern, working directly under the guidance of Planner Candace Gooding in D71. Given the prominence of the furniture and mattresses department in the online retail space, due to the limitations of in-store infrastructure for large products, our focus within D71 is centered on expanding the digital business. Over the past couple of years, Walmart has strategically shifted towards launching higher-end retail items, particularly in the realm of stylish furniture, bolstered by robust marketing initiatives. Although historical performance, seasonality, and price elasticity have traditionally guided forecasting for these items, the oversight of additional promotional support, such as influencer-promoted items like Drew Barrymore\u27s furniture line, has resulted in inventory forecasting discrepancies. These discrepancies subsequently led to Out of Stock (OOS) issues.
The project prompt that was assigned to me is as follows: “Develop a data-driven model that can help quantify sales unit increases from marketing promotions early enough to react accordingly and have sufficient inventory to meet forecasted demand. By having a more methodical and data-driven approach, we hoped to reduce risk by having a more educated forecast while taking on a big bet item. As the model becomes more robust, we can also start using this to quantify if the marketing investment drives additional sales and profit, since ROI an optimal marketing mix is most important”. Due to D71’s reliance on Walmart’s online platform for the majority of sales, the data analyzed in the scope of this project focused solely on online sales
Go Green or Go Viral?
Get PDFOur society has been altered by the proliferation of social media. Viral marketing and influencer marketing have increased the amount of products that dramatically increase in popularity, in other words - go viral. These trend cycles have led to the consumption of businesses that are not as moral as they seem. Has society replaced the priority of buying from good-willed businesses with buying from businesses that give them that new trendiest item? Has society lost its morality in purchasing concerning these trends