Digital Commons Network^™

Optimal Contest Design When Policing Damaging Behavior, Scott M. Gilpatric, Ye Hong

Economics Faculty Publications and Presentations

Abstract

International Rice Outlook: International Rice Baseline Projections 2022-2032, A. Durand-Morat, S. Bairagi, W. Mulimbi

AAES Research Reports and Research Bulletins

Rice prices in Asia increased since the Summer of 2022 mainly due to worries about a reduction in rice production in India caused by an abnormal monsoon season (Fig. 1). The upward trend in export prices solidified after India implemented a 20% export tariff on brown and milled long-grain rice, and a complete ban on exports of broken rice, in September 2022 to curve down exports and release the pressure on domestic rice prices. India’s rice export prices increased since then and proportionally to the value of the export tax. The latest estimates put rice production at 128 million metric …

Chemistry And Biochemistry Affiliated Publications: Snapshot Of The Research Publications 2019-2022, Jeremy Smith, Lutishoor Salisbury

University Libraries Faculty Publications and Presentations

This report highlights the chemistry and biochemistry faculty publications for the period 2019-2022.

It include tables identifying the types of publications, the JCR ranking of the journals in which they published and a listing of their publications, etc.

Lightning: An X-Ray To Submillimeter Galaxy Sed-Fitting Code With Physically Motivated Stellar, Dust, And Agn Models, Keith Doore, Erik B. Monson, Rafael T. Eufrasio, Bret D. Lehmer, Kristen Garofali, Antara Basu-Zych

Physics Faculty Publications and Presentations

We present an updated version of Lightning, a galaxy spectral energy distribution (SED) fitting code that can model X-ray to submillimeter observations. The models in Lightning include the options to contain contributions from stellar populations, dust attenuation and emission, and active galactic nuclei (AGNs). X-ray emission, when utilized, can be modeled as originating from stellar compact binary populations with the option to include emission from AGNs. We have also included a variety of algorithms to fit the models to observations and sample parameter posteriors; these include adaptive Markov Chain Monte Carlo (MCMC), affine-invariant MCMC, and Levenberg–Marquardt gradient-descent (MPFIT) algorithms. To …

Addressing The Embeddability Problem In Transition Rate Estimation, Curtis Goolsby, James Losey, Ashkan Fakharzadeh, Yuchen Xu, Marie-Christine Düker, Mila Getmansky Sherman, David S. Matteson, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

Markov State Models (MSM) and related techniques have gained significant traction as a tool for analyzing and guiding molecular dynamics (MD) simulations due to their ability to extract structural, thermodynamic, and kinetic information on proteins using computationally feasible MD simulations. The MSM analysis often relies on spectral decomposition of empirically generated transition matrices. This work discusses an alternative approach for extracting the thermodynamic and kinetic information from the so-called rate/generator matrix rather than the transition matrix. Although the rate matrix itself is built from the empirical transition matrix, it provides an alternative approach for estimating both thermodynamic and kinetic quantities, …

Diverged Landscape Of Restaurant Recovery From The Covid-19 Pandemic In The United States, Siqin Wang, Xiao Huang, Bing She, Zhenlong Li

Geosciences Faculty Publications and Presentations

The COVID-19 pandemic has imposed catastrophic impacts on the restaurant industry as a crucial socioeconomic sector that contributes to the global economy. However, the understanding of how the restaurant industry was recovered from COVID-19 remains underexplored. This study constructs a spatially explicit evaluation of the effect of COVID-19 on the restaurant industry in the US, drawing on the attributes of +200,000 restaurants from Yelp and +600 million individual-level restaurant visitations provided by SafeGraph from 1st January 2019 to 31st December 2021. We produce quantitative evidence of lost restaurant visitations and revenue amid the pandemic, the changes in the customers’ origins, …

Cpsrp43 Is Both Highly Flexible And Stable: Structural Insights Using A Combined Experimental And Computational Approach, Mitchell Benton, Mercede Furr, Vivek Govind Kumar, Adithya Polasa, Feng Gao, Colin David Heyes, Thallapuranam Krishnaswamy Suresh Kumar, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

The novel multidomain protein, cpSRP43, is a unique subunit of the post-translational chloroplast signal recognition particle (cpSRP) targeting pathway in higher plants. The cpSRP pathway is responsible for targeting and insertion of light-harvesting chlorophyll a/b binding proteins (LHCPs) to the thylakoid membrane. Upon emergence into the stroma, LHCPs form a soluble transit complex with the cpSRP heterodimer, which is composed of cpSRP43 and cpSRP54. cpSRP43 is irreplaceable as a chaperone to LHCPs in their translocation to the thylakoid membrane and remarkable in its ability to dissolve aggregates of LHCPs without the need for external energy input. In previous studies, cpSRP43 …

The Alternating Access Mechanism In Mammalian Multidrug Resistance Transporters And Their Bacterial Homologs, Shadi A. Badiee, Ugochi H. Isu, Ehsaneh Khodadadi, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

Multidrug resistance (MDR) proteins belonging to the ATP-Binding Cassette (ABC) transporter group play a crucial role in the export of cytotoxic drugs across cell membranes. These proteins are particularly fascinating due to their ability to confer drug resistance, which subsequently leads to the failure of therapeutic interventions and hinders successful treatments. One key mechanism by which multidrug resistance (MDR) proteins carry out their transport function is through alternating access. This mechanism involves intricate conformational changes that enable the binding and transport of substrates across cellular membranes. In this extensive review, we provide an overview of ABC transporters, including their classifications …

Pulaski County Education Report Card 2022, Sarah Mckenzie, Josh Mcgee, Trent Leslie, Christine L. Magness

Education Report Card

The goal of this report is to help parents, school personnel, community members, and policy makers understand how effectively the students in their community are being served by public schools. The past few years have been difficult for families, teachers, and students, and throughout the challenging context, Pulaski County students demonstrated growth in achievement on the Act Aspire that was similar to students across the state, but are performing below the state average in achievement, graduation rates, and School Quality and Student Success scores.

Northwest Arkansas Education Report Card 2022, Sarah Mckenzie, Josh Mcgee, Trent Leslie, Christine L. Magness

Education Report Card

The goal of this report is to help parents, school personnel, community members, and policy makers understand how effectively the students in their community are being served by public schools. The past two years have been difficult for families, teachers, and students, but despite the challenging context, Northwest Arkansas students are demonstrating greater growth in achievement and earning higher scores on the ACT Aspire than are the students in the state overall. Schools in NWA also received higher School Quality and Student Success scores and graduate a greater percentage of high school students.

Office Of Nationally Competitive Awards, Inquiry Editors

Inquiry: The University of Arkansas Undergraduate Research Journal

No abstract provided.

Inquiry: The Unversity Of Arkansas Undergraduate Research Journal - Volume 22 Issue 1 - Spring 2023, Inquiry Editors

Inquiry: The University of Arkansas Undergraduate Research Journal

No abstract provided.

Be Prepared: Online School Experience And Student Achievement During The Pandemic, Dennis Beck

Curriculum and Instruction Faculty Publications and Presentations

During the COVID-19 pandemic it was clear that not all schools were equally prepared to adapt to the challenges of online learning. While many traditional public schools struggled to transition to remote teaching, cyber charter schools–which already had experience with full-time online learning–appeared to demonstrate superior academic performance and less learning loss. This success may be due in part to the greater experience of these schools with online teaching, as well as that the type of student enrolling in cyber charters changed. Further research and external peer review is necessary to confirm the validity of these findings, but in the …

The Impact Of Frequent Student-Faculty Interactions On Repeater Students, Shanda Hood, Josh Girshner

TFSC Publications and Presentations

Second Annual University of Arkansas Teaching and Learning Symposium: Sharing Teaching Ideas

Data show that half of all students who have dropped/failed Survey of Calculus or Finite Mathematics at the University of Arkansas will drop/fail again. These students face a lack of motivation and a fair amount of anxiety toward mathematics. To make connections and create an environment in which they are comfortable discussing any issues with the professor, repeater students were asked to meet with the professor to complete a personalized academic improvement plan. This plan establishes the need for regular contact with the instructor and should increase the …

Analysis Of A Federated Learning Framework For Heterogeneous Medical Image Data: Privacy And Performance Perspective, Julia Brixey

Computer Science and Computer Engineering Undergraduate Honors Theses

The massive amount of data available in our modern world and the increase of computational efficiency and power have allowed for great advancements in several fields such as computer vision, image processing, and natural languages. At the center of these advancements lies a data-centric learning approach termed deep learning. However, in the medical field, the application of deep learning comes with many challenges. Some of the fundamental challenges are the lack of massive training datasets, unbalanced and heterogenous data between health applications and health centers, security and privacy concerns, and the high cost of wrong inference and prediction. One of …

A Survey And Comparative Study On Vulnerability Scanning Tools, Cassidy Khounborine

Computer Science and Computer Engineering Undergraduate Honors Theses

Vulnerability scanners are a tool used by many organizations and developers as part of their vulnerability management. These scanners aid in the security of applications, databases, networks, etc. There are many different options available for vulnerability scanners that vary in the analysis method they encompass or target for which they scan, among many other features. This thesis explores the different types of scanners available and aims to ease the burden of selecting the ideal vulnerability scanner for one’s needs by conducting a survey and comparative analysis of vulnerability scanners. Before diving into the vulnerability scanners available, background information is provided …

Characterization Of 2d Quantum Materials Using Ai And Large-Scale Quantum Data Collection, Apoorva Bisht

Computer Science and Computer Engineering Undergraduate Honors Theses

2D materials like hexagonal boron nitride, graphene, and tungsten diselenide are widely utilized for studying their unique mechanical and opto-electronic properties to exploit them to make transistors and fabricating a variety of other devices. All these applications require that the 2D materials used be of specific uniform thickness. Until very recently, this process has been largely manual and tedious. However, few applications exploit the characteristic color-to-thickness correspondence of these near-transparent materials. To continue this effort, in this work we create a large-scale dataset for three different materials (hBN, graphene, and WSe$_2$) to train and test an image segmentation model along …

The Use Of Fluorescence Resonance Energy Transfer And Bent Dna To Study Dna And Ion Interactions, Kaitlin Bullard

Physics Undergraduate Honors Theses

Studying DNA interactions is advantageous to developments in the medical field since DNA and its interactions affect our health greatly. In addition, it is important to understand how the bendability of DNA depends on metal ions, which are essential for various fundamental processes in cells. In this work, we investigate the use of FRET and self-assembled bent DNA molecules to quantify DNA interactions with magnesium ions. We measured that the FRET efficiency increased at higher concentrations of magnesium ions. We also ran simulations to further understand the mechanisms. These observations show that magnesium ions increase the stability and flexibility of …

Fabrication Of Black Phosphorus Terahertz Photoconductive Antennas, Nathan Tanner Sawyers

Physics Undergraduate Honors Theses

Terahertz (THz) photoconductive antennas (PCAs) using 40nm thin-film flakes of black phosphorus (BP) and hexagonal boron nitride (hBN) have been shown computationally to be capable of THz emission comparable to those based on GaAs [2]. In this paper, I briefly describe the scientific and practical interest in THz emissions and explain what warrants research into black phosphorus as a photoconductive semiconductor in THz devices. Furthermore, I outline the basic principle of how these antennas work and mention alternative designs produced by other researchers in the past. Finally, I summarize the fabrication process of these antennas, as well as the measurements …

Developing A Multi-Platform Application To Facilitate Internal Campus Hiring, Carissa Patton

Computer Science and Computer Engineering Undergraduate Honors Theses

Undergraduate research has proven to be highly beneficial to students, yet there are many students who do not know how to get involved or who are too timid to approach professors to inquire about potential research opportunities. Our hypothesis is that a cross-platform application has the potential to bridge the gap and help more students get involved in undergraduate research by providing them information about open positions and the faculty or staff members who are mentoring the projects. The key focus of this thesis is to develop an application that provides details about participating faculty or staff including their research …

Universal Computation Using Self-Assembling, Crisscross Dna Slats, Jackson S. Bullard

Computer Science and Computer Engineering Undergraduate Honors Theses

I first give a brief introduction to formal models of computation. I then present three different approaches for computation in the aTAM. I later detail generating systems of crisscross slats given an arbitrary algorithm encoded in the form of a Turing machine. Crisscross slats show potential due to their high levels of cooperativity, so it is hoped that implementations utilizing slats are more robust to various growth errors compared to the aTAM. Finally, my software converts arbitrary crisscross slat systems into various physical representations that assist in analyzing their potential to be realized in experiments.

Linux Malware Obfuscation, Brian Roden

Computer Science and Computer Engineering Undergraduate Honors Theses

Many forms of malicious software use techniques and tools that make it harder for their functionality to be parsed, both by antivirus software and reverse-engineering methods. Historically, the vast majority of malware has been written for the Windows operating system due to its large user base. As such, most efforts made for malware detection and analysis have been performed on that platform. However, in recent years, we have seen an increase in malware targeting servers running Linux and other Unix-like operating systems resulting in more emphasis of malware research on these platforms. In this work, several obfuscation techniques for Linux …

Design Of A Sigma-Delta Adc In 65nm Cmos Process, Michael Lee Thompson Iii

Electrical Engineering Undergraduate Honors Theses

Analog and digital signals both play a vital role in electrical engineering and the technology of today. As the role of electrical and computer engineers becomes more deeply involved in the development of new technology, an understanding of how these signals are utilized, and what they represent, is a necessity. Due to the inherent limitations involved with analog signals, there is a need for these signals to be accurately and efficiently converted to digital signals for processing. The job of the analog-to-digital converter, or ADC, is to receive this analog input signal (voltage or current) and create a digital representation …

Geochemical Analysis And Numerical Modeling Of Central And East Tennessee Mississippi Valley-Type Ore Districts: Constraints On Ore Genesis, Jackson Price Copeland

Geosciences Undergraduate Honors Theses

A simple two-way stochastic mixing model is presented for analysis of the lead (Pb) isotope compositions of the North American Mississippi Valley-Type (MVT) districts of East Tennessee, Central Tennessee, and Central Kentucky. Four distinct mixing scenarios were run to critically evaluate the stochastic model and examine different hypotheses regarding the genesis of Central Tennessee and Central Kentucky MVT deposits. Additionally, Pb isotope analysis was conducted on sphalerite samples from the Central and East Tennessee MVT districts. Model and sampling results suggest that Central Tennessee and Central Kentucky ores likely formed by mixing of three fluids. In contrast to conclusions from …

Reverse Engineering Post-Quantum Cryptography Schemes To Find Rowhammer Exploits, Sam Lefforge

Computer Science and Computer Engineering Undergraduate Honors Theses

Post-quantum cryptography is a necessary countermeasure to protect against attacks from quantum computer. However, the post-quantum cryptography schemes are potentially vulnerable to side channel attacks. One such method of attacking involves creating bit-flips in victim memory through a process called Rowhammer. These attacks can vary in nature, but can involve rowhammering bits to raise the encryption scheme's decryption failure rate, or modifying the scheme's random seed. With a high enough decryption failure rate, it becomes feasible to generate sufficient information about the secret key to perform a key recovery attack. This thesis proposed two attacks on proposed post-quantum cryptography algorithms, …

Realtime In-Network Cyberattack Detection In Power Grid Systems Using A Programmable Network, Luke Waind

Computer Science and Computer Engineering Undergraduate Honors Theses

Power grid communication networks are important systems to detect intrusions from an attacker due to them being necessary to maintain critical infrastructure. This thesis applies recent advancements in P4 technology to detect cyberattacks in SCADA systems. In previous work, a list has been compiled of potential attacks that exploit one of the most common protocols in SCADA systems, DNP3. Solutions for detecting these attacks can be categorized by the broad methods that they use. The two methods that are focused on are single-packet inspection and multiple-packet inspection. For each of these, a specific attack is chosen and a detection algorithm …

Critical Infrastructure Workforce Development Pods For Teaching Cybersecurity Using Netlab+, Gideon Sutterfield

Computer Science and Computer Engineering Undergraduate Honors Theses

As digital automation for Industrial Control Systems has grown, so has its vulnerability to cyberattacks. The world of industry has responded effectively to this, but the world of academia is still lagging as its emphasis is still almost entirely on information technology. Considering this, we created a workforce development pod that serves as a hands-on learning module for teaching students key cybersecurity ideas surrounding operational technology using the NETLAB+ platform. A pod serves as the virtual environment where the learning exercise takes place. This project’s implementation involved the creation of a segmented network within the pod where a student starts …

Gradient Estimates And The Fundamental Solution For Higher-Order Elliptic Systems With Lower-Order Terms, Ariel E. Barton, Michael J. Duffy Jr.

Mathematical Sciences Faculty Publications and Presentations

We establish the Caccioppoli inequality, a reverse Hölder inequality in the spirit of the classic estimate of Meyers, and construct the fundamental solution for linear elliptic differential equations of order 2m with certain lower order terms.

Quantifying The Effect Of Socio-Economic Predictors And The Built Environment On Mental Health Events In Little Rock, Ar, Alfieri Ek, Grant Drawve, Samantha Robinson, Jyotishka Datta

Sociology and Criminology Faculty Publications and Presentations

Law enforcement agencies continue to grow in the use of spatial analysis to assist in identifying patterns of outcomes. Despite the critical nature of proper resource allocation for mental health incidents, there has been little progress in statistical modeling of the geo-spatial nature of mental health events in Little Rock, Arkansas. In this article, we provide insights into the spatial nature of mental health data from Little Rock, Arkansas between 2015 and 2018, under a supervised spatial modeling framework. We provide evidence of spatial clustering and identify the important features influencing such heterogeneity via a spatially informed hierarchy of generalized …

Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers

Physics Undergraduate Honors Theses

Under continuous excitation, quantum dots exhibit random transitions between fluorescent ON states and non-fluorescent OFF states --- a phenomenon known as blinking. A physical description of the mechanism responsible for blinking that applies broadly to many types of quantum dots remains under debate. We study the blinking behavior of the non-toxic CuInS2 quantum dot, a system that has seen little investigation at the single-particle level. In particular, the optical properties of CuInS2 quantum are often improved by adding ZnS to the nanoparticles, but this addition leads to complex structural-optical property relationships that are even less understood. To probe the relationship …