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Enhancing Smart Grid Security And Resilience Using Programmable Networks, Zheng Hu

Graduate Theses and Dissertations

The security and resilience of smart grids are essential to ensuring reliable and efficient energy distribution, especially as these cyber-physical systems grow more interconnected and complex. Supervisory Control and Data Acquisition (SCADA) systems play a critical role in smart grid operations by enabling essential infrastructure control and real-time monitoring. However, SCADA systems are highly vulnerable to modern cyber threats, which target weaknesses in industrial protocols and real-time data requirements.

This dissertation investigates the potential of programmable network technologies, with a focus on P4 (Programming Protocol-independent Packet Processors) switch, to deliver adaptable, in-network security solutions tailored to the needs of smart …

Intersectionality And Career Persistence Of African American Women In Cybersecurity Careers: A Narrative Inquiry, Monica Marquita Jones Prewitt

Graduate Theses and Dissertations

The purpose of this narrative inquiry is to examine the experiences of African American women working in cybersecurity, a male-dominated field. An intersectional lens will be used in the study to provide insight into their positionality as women of color in a male-dominated career field. The study will examine the stories of the women who persisted in the field and the existing influences or interventions that supported their retention. This pre-registered study will provide the framework for this study to be completed at the University of Arkansas. The researcher will use a descriptive phenomenological approach and semi-structured interviews to understand …

Causal Discovery In Time Series Data Using Deep Learning Techniques, Saima Zahin Farhana Absar

Graduate Theses and Dissertations

Causal structure learning from observational data has been an active field of research over the past decades. In the literature, different algorithms and models have been proposed, such as constrained-based methods and score-based methods including the emerging deep learning-based methods. However, most of the approaches apply to static and non-dynamic data only. In many applications, the data is temporal. For example, monitoring systems, weather surveillance systems, and stock data, to name but a few. Incorporating temporal information is an important extension of the causal discovery field. With the growth of observational data these days, the discovery of causal relationships from …

Carbon Dioxide Dynamics In The Carbonate Critical Zone, Savoy Experimental Watershed, Arkansas, Usa, Michael Darvin Jones

Graduate Theses and Dissertations

The dynamics of carbon dioxide (CO₂) within the Earth’s critical zone (CZ) are essential for driving spatial and temporal variations of carbonate dissolution and precipitation, which are fundamental to subsurface porosity and permeability development. However, there is still a significant knowledge gap regarding the patterns of CO₂ transport and production within the carbonate critical zone (CCZ). In this study, we investigated these dynamics within a mantled karst terrain at the Savoy Experimental Watershed (SEW) in Northwest Arkansas.

Previous monitoring of partial pressure of CO₂ (PCO₂) and dissolution rates at karst springs in …

The Learning Crisis: Three Years After Covid-19, Tomasz Gajderowicz, Maciej Jakubowski, Alec Kennedy, Christian Christrup Kjeldsen, Harry Anthony Patrinos, Rolf Strietholt

Education Reform Faculty and Graduate Students Publications

The COVID-19 pandemic caused widespread disruptions to education, with school closures affecting over one billion children. These closures, aimed at reducing virus transmission, resulted in significant learning losses, particularly in mathematics and science. Using data from TIMSS 2023, which assesses fourth and eighth-grade achievements across 71 education systems, this study analyzes the impact of school closure duration on learning outcomes. Mixed-effect models estimate deviations from pre-pandemic trends, adjusting for demographic factors. Results show a global average decline of 0.11 standard deviations (SD) in student achievement, with longer closures linked to more severe losses. The effects on low performers, girls, and …

Predictive Model For Listeria Monocytogenes In Rte Meats Using Exclusive Food Matrix Data, N.A. Nanje Gowda, Manjari Singh, Gijs Lommerse, Saurabh Kumar, Eelco Heintz, Jeyamkondan Subbiah

Food Science Faculty Publications and Presentations

Post-processing contamination of Listeria monocytogenes has remained a major concern for the safety of ready-to-eat (RTE) meat products that are not reheated before consumption. Mathematical models are rapid and cost-effective tools to predict pathogen behavior, product shelf life, and safety. The objective of this study was to develop and validate a comprehensive model to predict the Listeria growth rate in RTE meat products as a function of temperature, pH, water activity, nitrite, acetic, lactic, and propionic acids. The Listeria growth data in RTE food matrices, including RTE beef, pork, and poultry products (731 data sets), were collected from the literature …

Toward Dissolving The Institutionalization Of “Othering”: Organizational Conditions That Support Shared Responsibility, Jennifer R. Cowhy, Lok-Sze Wong, Megan Hopkins

Counseling, Leadership, and Research Methods Faculty Publications and Presentations

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Chloronitramide Anion Is A Decomposition Product Of Inorganic Chloramines, Julian L. Fairey

Civil Engineering Faculty Publications and Presentations

Editor’s summary

Cus-Nite2 Embedded Phosphorus-Doped Graphene Oxide Catalyst For Evaluating Hydrogen Evolution Reaction, Sedigheh Parvaz, Zahra Talebi Vandishi, Ali A. Ensafi, Kimia Zarean Mousaabadi

Chemistry & Biochemistry Faculty Publications and Presentations

The hydrogen evolution reaction (HER), a crucial half-reaction in the water-splitting process, is hindered by slow kinetics, necessitating efficient electrocatalysts to lower overpotential and enhance energy conversion efficiency. Transition-metal electrode materials, renowned for their robustness and effectiveness, have risen to prominence as primary contenders in the field of energy conversion and storage research. In this investigation, we delve into the capabilities of transition metals when employed as catalysts for the HER. Furthermore, we turn our attention to carbon nanomaterials like graphene, which have exhibited tremendous potential as top-performing electrocatalysts. Nevertheless, advancements are indispensable to expand their utility and versatility. One …

Liquid Crystalline Collagen Assemblies As Substrates For Directed Alignment Of Human Schwann Cells, Homa Ghaiedi, Luis Carlos Pinzon-Herrera, Saja Alshafeay, Leonard Harris, Jorge Almodovar, Karthik Nayani

Chemical Engineering Faculty Publications and Presentations

Collagen is a key component of the extracellular matrix (ECM) and well-oriented domains of collagen are important for mimicking the local cell environment in vitro. While there has been significant attention directed towards the alignment of collagen, formation of large-scale oriented domains remains a key challenge. Type I collagen self-assembles to form liquid crystalline (LC) mesophases in acidic conditions at concentrations above 100 mg mL−1. The LC mesophase provides an efficient platform for large-scale alignment and patterning of collagen coated substrates. However, there still exist challenges related to solubilizing and processing of collagen at such high concentrations in order …

A Liquid Crystal-Based Biomaterial Platform For Rapid Sensing Of Heat Stress Using Machine Learning, Prateek Verma, Elizabeth Adeogun, Elizabeth S. Greene, Sami Dridi, Ukash Nakarmi, Karthik Nayani

Poultry Science Faculty Publications and Presentations

Novel biomaterials that bridge the knowledge gap in coupling molecular/protein signatures of disease/stress with rapid readouts are a critical need of society. One such scenario is an imbalance between bodily heat production and heat dissipation which leads to heat stress in organisms. In addition to diminished animal well-being, heat stress is detrimental to the poultry industry as poultry entails fast growth and high yields, resulting in greater metabolic activity and higher body heat production. When stressed, cells overexpress heat shock proteins (such as HSP70, a well-established intracellular stress indicator) and may undergo changes in their mechanical properties. Liquid crystals (LCs, …

Geosciences Affiliated Publications: Snapshot Of The Research Publications 2018-2023, Danna Jaimes-Fajardo, Jeremy J. Smith, Lutishoor Salisbury

University Libraries Faculty Publications and Presentations

This report provides a snapshot of the research publications for authors affiliated with the Geosciences department at the University of Arkansas, Fayetteville, for the period 2018-2023. It includes publications by material type; co-author characteristics; ranking of journals according to journal citation reports.

Insulator-To-Metal Transition And Isotropic Gigantic Magnetoresistance In Layered Magnetic Semiconductors, Gokul Acharya, Bimal Neupane, Chia-Hsiu Hsu, Xian P. Yang, David Graf, Eun Sang Choi, Krishna Pandey, Md Rafique Un Nabi, Santosh Karki Chhetri, Rabindra Basnet, Sumaya Rahman, Jian Wang, Zhengxin Hu, Bo Da, Hugh O.H. Churchill, Guoqing Chang, M. Zahid Hasan, Yuanxi Wang, Jin Hu

Physics Faculty Publications and Presentations

Magnetotransport, the response of electrical conduction to external magnetic field, acts as an important tool to reveal fundamental concepts behind exotic phenomena and plays a key role in enabling spintronic applications. Magnetotransport is generally sensitive to magnetic field orientations. In contrast, efficient and isotropic modulation of electronic transport, which is useful in technology applications such as omnidirectional sensing, is rarely seen, especially for pristine crystals. Here a strategy is proposed to realize extremely strong modulation of electron conduction by magnetic field which is independent of field direction. GdPS, a layered antiferromagnetic semiconductor with resistivity anisotropies, supports a field-driven insulator-to-metal transition …

Lithicone-Protected Lithium Metal Anodes For Lithium Metal Batteries With Nickel-Rich Cathode Materials, Ridwan A. Ahmed, Kevin V. Carballo, Krishna P. Koirala, Qian Zhao, Peiyuan Gao, Ju-Myung Kim, Cassidy S. Anderson, Xiangbo Meng, Chongmin Wang, Ji-Guang Zhang, Wu Xu

Mechanical Engineering Faculty Publications and Presentations

The high energy density advantage of lithium (Li) metal batteries (LMBs) makes them increasingly desirable; however, problems such as strong reactivity and dendrite growth of Li metal anode limit their practical uses. In this work, a novel Li-containing glycerol (LiGL) or lithicone protection layer on a 50 μm thick Li metal anode is employed for improving the performance of LMBs. This LiGL layer was accurately deposited via a molecular layer deposition (MLD) process at 150°C, using lithium tert-butoxide and glycerol as precursors. The as-formed LiGL coating layer is highly tunable in its thickness by simply adjusting MLD cycles and shows …

Connecting Compassion: Empathy's Role In Stem And Literacy Integration, Leah R. Cheek, Vinson Carter, Michael K. Daugherty, Christian Goering

Curriculum and Instruction Faculty Publications and Presentations

Empathy, an unsung, yet critical element of learning, can be strategically interlaced with literacy instruction and engineering design to create a rich and authentic learning experience for students. Integrated STEM education rests on the promise of engaging students and providing deep understandings through the intentional practice of delivering science and math content through the application of technology and engineering skills. Using children's literature to activate empathy and design thinking can help students become better problem-solvers, critical thinkers, and caring members of society. Empathy facilitates a deeper connection to the human experience, ensuring that solutions not only meet the design requirements, …

Bridging Human And Machine Intelligence: Reverse-Engineering Radiologist Intentions For Clinical Trust And Adoption, Akash Awasthi, Ngan Le, Zhigang Deng, Rishi Agrawal, Carol C. Hu, Hien Van Nguyen

Computer Science and Computer Engineering Faculty Publications and Presentations

In the rapidly evolving landscape of medical imaging, the integration of artificial intelligence (AI) with clinical expertise offers unprecedented opportunities to enhance diagnostic precision and accuracy. Yet, the "black box" nature of AI models often limits their integration into clinical practice, where transparency and interpretability are important. This paper presents a novel system leveraging the Large Multimodal Model (LMM) to bridge the gap between AI predictions and the cognitive processes of radiologists. This system consists of two core modules, Temporally Grounded Intention Detection (TGID) and Region Extraction (RE). The TGID module predicts the radiologist's intentions by analyzing eye gaze fixation …

The Divergent Responses Of Salinity Generalists To Hyposaline Stress Provide Insights Into The Colonisation Of Freshwaters By Diatoms, Kathryn J. Judy, Eveline Pinseel, Kala M. Downey, Jeffrey A. Lewis, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

Environmental transitions, such as the salinity divide separating marine and fresh waters, shape biodiversity over both shallow and deep timescales, opening up new niches and creating opportunities for accelerated speciation and adaptive radiation. Understanding the genetics of environmental adaptation is central to understanding how organisms colonise and subsequently diversify in new habitats. We used time-resolved transcriptomics to contrast the hyposalinity stress responses of two diatoms. Skeletonema marinoi has deep marine ancestry but has recently invaded brackish waters. Cyclotella cryptica has deep freshwater ancestry and can withstand a much broader salinity range. Skeletonema marinoi is less adept at mitigating even mild …

Molecular Dynamics Investigation Of The Influenza Hemagglutinin Conformational Changes In Acidic Ph, Shadi A. Badiee, Vivek Govind Kumar, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

The surface protein hemagglutinin (HA) of the influenza virus plays a pivotal role in facilitating viral infection by binding to sialic acid receptors on host cells. Its conformational state is pH-sensitive, impacting its receptor-binding ability and evasion of the host immune response. In this study, we conducted extensive equilibrium microsecond-level all-atom molecular dynamics (MD) simulations of the HA protein to explore the influence of low pH on its conformational dynamics. Specifically, we investigated the impact of protonation on conserved histidine residues (H106₂) located in the hinge region of HA2. Our analysis encompassed comparisons between nonprotonated (NP), partially protonated …

Noncontact Diffuse Reflectance Spectroscopy Of Synovial Fluid Samples For Rapid Identification Of Infections, Erin E. Drewke, Robert L. Brand, Caroline G. Geels, Hanna K. Jensen, Kevin Wong, Jarret D. Sanders, Narasimhan Rajaram

Biomedical Engineering Faculty Publications and Presentations

Severe joint infections, such as septic arthritis, require rapid diagnostic testing of the synovial fluid aspirated from joints level so that a surgical team can be assembled quickly. We present a diffuse reflectance spectroscopy (DRS) system for noncontact determination of infection. Using a light-tight syringe holder and fiber optic probe, diffusely reflected light from 475 to 655 nm was acquired from 18 patient samples through the wall of a syringe in a noncontact and sterile manner. We determined the reflectance ratios at two different wavelengths—R ₄₉₀/R ₆₀₀ and R ₅₈₀/R ₆₀₀ and found statistically significant …

Unlocking College Potential: The Role Of Student Expectations And Non-Cognitive Skills In College Success, Gema Zamarro, Malachi Nichols, Julie R. Trivitt, Rian Djita

Education Reform Faculty and Graduate Students Publications

Attending college is a significant human capital investment but only about 60% of those who start college will have a completed degree six years later. This makes identifying the skills associated with college success an important policy concern. We surveyed over 1,100 entering college freshmen, majoring in business and engineering at a public university in the US, and combined this information with administrative data to create a comprehensive data set that, in addition to the usual academic performance data, cognitive ability measures, and demographics, also included measures of non-cognitive skills, personality traits, student expectations about college success and performance at …

Advancing Crispr-Based Solutions For Covid-19 Diagnosis And Therapeutics, Roaa Hadi, Abhishek Poddar, Shivakuma Sonnaila, Venkata Suryanarayana Murthy Bhavaraju, Shilpi Agrawal

Chemistry & Biochemistry Faculty Publications and Presentations

Since the onset of the COVID-19 pandemic, a variety of diagnostic approaches, including RT-qPCR, RAPID, and LFA, have been adopted, with RT-qPCR emerging as the gold standard. However, a significant challenge in COVID-19 diagnostics is the wide range of symptoms presented by patients, necessitating early and accurate diagnosis for effective management. Although RT-qPCR is a precise molecular technique, it is not immune to false-negative results. In contrast, CRISPR-based detection methods for SARS-CoV-2 offer several advantages: they are cost-effective, time-efficient, highly sensitive, and specific, and they do not require sophisticated instruments. These methods also show promise for scalability, enabling diagnostic tests. …

The Projected Exposure And Response Of A Natural Barrier Island System To Climate-Driven Coastal Hazards, Jennifer A. Thomas, Patrick L. Barnard, Sam Vitousek, Li H. Erikson, Kai Parker, Kees Nederhoff, K. M. Befus, Manoochehr Shirzaei

Geosciences Faculty Publications and Presentations

Accelerating sea level rise (SLR) and changing storm patterns will increasingly expose barrier islands to coastal hazards, including flooding, erosion, and rising groundwater tables. We assess the exposure of Cape Lookout National Seashore, a barrier island system in North Carolina (USA), to projected SLR and storm hazards over the twenty-first century. We estimate that with 0.5 m of SLR, 47% of current subaerial barrier island area would be flooded daily, and the 1-year return period storm would flood 74%. For 20-year return period storms, over 85% is projected to be flooded for any SLR. The modelled groundwater table is already …

Conformational Cycle Of A Protease-Containing Abc Transporter In Lipid Nanodiscs Reveals The Mechanism Of Cargo-Protein Coupling, Ruojiing Zhang, Kevin L. Jagessar, University Of Arkansas, Fayetteville, Adithya Polasa, Richard A. Stein, Mahmoud Moradi, Erkan Karakas, Hassane S. Mchaourab

Chemistry & Biochemistry Faculty Publications and Presentations

Protease-containing ABC transporters (PCATs) couple the energy of ATP hydrolysis to the processing and export of diverse cargo proteins across cell membranes to mediate antimicrobial resistance and quorum sensing. Here, we combine biochemical analysis, single particle cryoEM, and DEER spectroscopy in lipid bilayers along with computational analysis to illuminate the structural and energetic underpinnings of coupled cargo protein export. Our integrated investigation uncovers competitive interplay between nucleotides and cargo protein binding that ensures the latter’s orderly processing and subsequent transport. The energetics of cryoEM structures in lipid bilayers are congruent with the inferred mechanism from ATP turnover analysis and reveal …

Strategic Light Use Efficiency Optimization Of Hydroponic Lettuce Exposed To Different Photosynthetic Photon Flux Densities, Peyton Lou Palsha, Marc W, Van Iersel, Ryan W. Dickson, Lynne Seymour, Kuan Qin, Rhuanito Saranz Ferrarezi

Horticulture Faculty Publications and Presentations

Light use efficiency characterizes the ability of a crop to convert radiation into biomass. Determining optimum cultivar-specific photosynthetic photon flux density (PPFD) values from sole-source lighting can be used to optimize leaf expansion, maximize biomass, and shorten the production period. This study evaluated the growth of hydroponic lettuce (Lactuca sativa) ‘Rex’ cultivated under different PPFD levels using sole-source lighting. At lower PPFD levels of 201 to 292 µmol·m⁻²·s⁻¹, the plant projected canopy size (PCS) and specific leaf area increased to enhance light capture by 36.2% as compared to higher PPFD levels (333 and 413 µmol·m^{−2 …}

Leveraging Imitation Learning In Agricultural Robotics: A Comprehensive Survey And Comparative Analysis, Siavash Mahmoudi, Amirreza Davar, Pouya Sohrabipour, Ramesh Bahadur Bist, Yang Tao, Dongyi Wang

Biological and Agricultural Engineering Faculty Publications and Presentations

Imitation learning (IL), a burgeoning frontier in machine learning, holds immense promise across diverse domains. In recent years, its integration into robotics has sparked significant interest, offering substantial advancements in autonomous control processes. This paper presents an exhaustive insight focusing on the implementation of imitation learning techniques in agricultural robotics. The survey rigorously examines varied research endeavors utilizing imitation learning to address pivotal agricultural challenges. Methodologically, this survey comprehensively investigates multifaceted aspects of imitation learning applications in agricultural robotics. The survey encompasses the identification of agricultural tasks that can potentially be addressed through imitation learning, detailed analysis of specific models …

Investigating In Vivo Tumor Biomolecular Changes Following Radiation Therapy Using Raman Spectroscopy, Varsha Karunakaran, Sina Dadgar, Santosh K. Paidi, April Mordi, Whitney A. Lowe, Umme Marium Mim, Jesse D. Ivers, Joel Rodriguez Troncoso, Jared A. Mcpeake, Alric Fernandes, Sanidhya D. Tripathi, Ishan Barman, Narasimhan Rajaram

Biomedical Engineering Faculty Publications and Presentations

Treatment resistance is a major bottleneck in the success of cancer therapy. Early identification of the treatment response or lack thereof in patients can enable an earlier switch to alternative treatment strategies that can enhance response rates. Here, Raman spectroscopy was applied to monitor early tumor biomolecular changes in sensitive (UM-SCC-22B) and resistant (UM-SCC-47) head and neck tumor xenografts for the first time in in vivo murine tumor models in response to radiation therapy. We used a validated multivariate curve resolution-alternating least-squares (MCR-ALS) model to resolve complex multicomponent Raman spectra into individual pure spectra and their respective contributions. We observed …

Crystal Archer: Profile Of The Newest Chbc Faculty Member, Danna Jaimes-Fajardo, Jeremy J. Smith, Lutishoor Salisbury

University Libraries Faculty Publications and Presentations

Presents the research profile of Crystal Archer, Assistant Professor, Chemistry and Biochemistry department. It highlights her research interests, education, and impact of her research.

Substrate Interference And Strain In The Second-Harmonic Generation From Mose2 Monolayers, Sudeep Puri, Sneha Patel, Jose Luis Cabellos, Luis Enrique Rosas-Hernandez, Kaitlin Reynolds, Hugh O.H. Churchill, Salvador Barraza-Lopez, Bernardo S. Mendoza, Hiroyuki Nakamura

Physics Faculty Publications and Presentations

Nonlinear optical materials of atomic thickness, such as non-centrosymmetric 2H transition metal dichalcogenide monolayers, have a second-order nonlinear susceptibility (χ⁽²⁾) whose intensity can be tuned by strain. However, whether χ⁽²⁾ is enhanced or reduced by tensile strain is a subject of conflicting reports. Here, we grow high-quality MoSe₂ monolayers under controlled biaxial strain created by two different substrates and study their linear and nonlinear optical responses with a combination of experimental and theoretical approaches. Up to a 15-fold overall enhancement in second-harmonic generation (SHG) intensity is observed from MoSe₂ monolayers grown on SiO₂ when …

Unlocking The Secrets Of Porous Silicon Formation: Insights Into Magnesiothermic Reduction Mechanism Using In Situ Powder X-Ray Diffraction Studies, Sarah A. Martell, Maximilian Yan, Robert H. Coridan, Kevin H. Stone, Siddharth V. Patwardhan, Mita Dasog

Chemistry & Biochemistry Faculty Publications and Presentations

The magnesiothermic reduction of SiO₂ is an important reaction as it is a bulk method that produces porous Si for a wide range of applications directly from SiO₂. While its main advantage is potential tunability, the reaction behavior and final product properties are heavily dependent on many parameters including feedstock type. However, a complete understanding of the reaction pathway has not yet been achieved. Here, using in situ X-ray diffraction analysis, for the first time, various pathways through which the magnesiothermic reduction reaction proceeds were mapped. Further, the key parameters and conditions that determine which pathways are …

Polyphenol-Induced Protein Structural Modifications In Sorghum On Pasting Properties, Annegret Jannasch, Ya-Jane Wang, Sun-Ok Lee, Rohana Liyanage, Zeina Alraawi, Suresh Kumar Thallapuranam, William L. Rooney

Chemistry & Biochemistry Faculty Publications and Presentations

Black sorghum contains a high amount of anthocyanins and proanthocyanidins, whereas white sorghum predominantly comprises phenolic acids. Polyphenols covalently and non-covalently interact with protein, whereas the structure of both compounds affects these interactions. This study investigated the interactions between phenolic acids, anthocyanins, proanthocyanidins and prolamin, which is the major protein fraction in sorghum, and their effect on the pasting properties of white and black, whole and milled sorghum using different chemical agents. Urea increased the pasting viscosity of black sorghum, but not that of white sorghum, indicating that hydrogen bonds and hydrophobic interactions between prolamin and anthocyanins and proanthocyanidins play …