Digital Commons Network^™

Gate-Controlled Quantum Dots In Two-Dimensional Tungsten Diselenide And One-Dimensional Tellurium Nanowires, Shiva Davari Dolatabadi

Graduate Theses and Dissertations

This work focuses on the investigation of gate-defined quantum dots in two-dimensional transition metal dichalcogenide tungsten diselenide (WSe2) as a means to unravel mesoscopic physical phenomena such as valley-contrasting physics in WSe2 flakes and its potential application as qubit, as well as realizing gate-controlled quantum dots based on elementaltellurium nanostructures which may unlock the topological nature of the host material carriers such as Weyl states in tellurium nanowires.The fabrication and characterization of gate-defined hole quantum dots in monolayer and bilayer WSe2 are reported. The gate electrodes in the device design are located above and below the WSe2 nanoflakes to accumulate …

The Human Natural Resource Endowment Of Limestone For Cement Manufacturing, Vanya Marie North

Graduate Theses and Dissertations

This study investigates the total per-capita allocation of limestone globally. Termed the Human Natural Resource Endowment (HNRE), it is calculated by subtracting the cumulative annual production from the ultimately recoverable reserve (URR) of limestone and dividing the difference by global population. HNRE represents a unique way of visualizing resource depletion by asking how much of a given resource can be allocated to each person on earth, and how long that allocation can last given multiple population and usage scenarios. The average American, born in 2021, will use approximately 23,930 kgs of cement in their lifetime, with similar demands globally. Demand …

A Method For Exploring The Habitability Of Earth-Like Exoplanets: Applications To Tess Objects Of Interest 203 B, 256 B, And 700 D, Paul Bonney

Graduate Theses and Dissertations

The Transiting Exoplanet Survey Satellite (TESS) has and is continuing to discover a multitude of potentially habitable planet candidates. As more planets are detected and confirmed, it becomes increasingly important to strategically search for signs of habitability with which to differentiate and prioritize them for further observation, in particular with the James Webb Space Telescope (JWST). To facilitate this, I have created a method for prioritizing TESS planet candidates based on parameters derived from their light curves and have applied the method to the TESS Candidate Target List (CTL). This data set uses preliminary fits to transit modeling which can …

Short-Term Changes Within An Agroforestry System Managed At Three Basal Areas With Fescue Compared To Orchardgrass, Matthew Janorschke

Graduate Theses and Dissertations

Silvopasture practices incorporate forages and woody perennials in the same system in order to create a sustainable system. The main objective of this study was to determine if one of two forage species can be successfully established in order to investigate agroforestry as a management system to promote soil health. Within a bottomland mixed hardwood forest in the Arkansas River Valley, an agroforestry system was established to evaluate three basal areas (determined as the cross-sectional area of trees at breast height) (7, 11.5, and 16 m2/ha) with mounded areas and two forages, tall fescue (Lolium arundinaceum [Schreb.] Darbysh) and orchardgrass …

Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray

Graduate Theses and Dissertations

Life is remarkable in how resilient it can be. Many organism, classified as ex- tremophiles, can not only survive in extreme environments, but they can thrive in them. In the search for extraterrestrial life, the best candidates to harbor life exist with some kind of extreme condition. Europa, for example, is a favorite for the possibility of accommodating life as we know it within our solar system. Thought there is believed to be a liquid ocean under its icy surface, this habitat would be under immense pressures and high salinity. To best know where to look for extraterrestrial life, it …

Nitrogen Use Efficiency Of Pretassel Nitrogen Applications In Corn, Robyn Brittlee Mulloy

Graduate Theses and Dissertations

Corn (Zea mays L.) production continues to be a critical component of row-crop production systems within Arkansas and is seeing a resurgence in recent years. Nitrogen (N) is critical for corn growth and is often one of the single largest input costs associated with corn production. Research objectives for this study were to determine the nitrogen use efficiency (NUE) of late season N applications as influenced by sidedress N rate and timing of pretassel application and to quantify the nutrient uptake and partitioning in modern era corn hybrids within a furrow-irrigated production system. Research was conducted at the Milo J. …

Evaluation Of Extended Aging Type And Cooking Practices On Palatability Of Beef Steaks, Katharine Anne Bugenhagen

Graduate Theses and Dissertations

Two studies were conducted to determine if sous vide was a viable way to improve palatability of various beef cuts, and to determine whether extended aging duration and the presence of a bone impacts the consumer ratings of beef short loins.When evaluating the impact of sous vide cooking (SVG) on multiple beef muscles, there was a muscle × method interaction for overall liking (P = 0.04). The traditionally cooked (TRAD) Longisimus lumborum (LL) was rated the highest (P < 0.05). The Chuckeye steak (CHE) was rated next, both TRAD and SVG, with the traditional ranked higher, this was followed by the Triceps brachii (TB) also for both TRAD and SVG, however for the TB the SVG ranked higher (P < 0.05). The TRAD Biceps femoris (BF) rated the lowest (P < 0.05) of all of the muscles. Shear force did no differ between the cooking treatments (P > 0.05), or was there an interaction between muscle × method for shear force measurements (P < 0.05). The LL was rated the highest for tenderness (P < 0.05) while the BF was rated the lowest (P < 0.05). The second study compared subprimals aged over three aging periods (21, 42 63 days), then split into bone-in or boneless steaks, there were no interactions observed within the consumer data (P ≥ 0.05). BI steaks were rated higher (P < 0.05) for juiciness and overall liking by consumers, however BI and BL were rated similarly by consumers for tenderness and flavor (P > 0.05). When evaluated by consumers, aging did …

Design And Comparison Of Asynchronous Fft Implementations, Julie Bigot

Graduate Theses and Dissertations

Fast Fourier Transform (FFT) is a widely used digital signal processing technology in a large variety of applications. For battery-powered embedded systems incorporating FFT, its physical implementation is constrained by strict power consumption, especially during idle periods. Compared to the prevailing clocked synchronous counterpart, quasi-delay insensitive asynchronous circuits offer a series of advantages including flexible timing requirement and lower leakage power, making them ideal choices for these systems. In this thesis work, various FFT configurations were implemented in the low-power Multi-Threshold NULL Convention Logic (MTNCL) paradigm. Analysis illustrates the area and power consumption trends along the changing of the number …

Investigating Quality Attributes And Wine Production Methods Of Arkansas-Grown Grapes, Amanda Fleming

Graduate Theses and Dissertations

Grapevines (Vitis species) are grown worldwide to produce table grapes, juice grapes, dried grapes, and wine with the United States as one of the world’s largest wine and grape producers. Though not a large contributor to the U.S. grape and wine industry, Arkansas’ industry plays an important role in the state’s agritourism and economy. Most grapes grown in Arkansas’ warm climate include native species, such as muscadines (V. rotundifolia) and hybrids (crosses of Vitis species). Two important hybrid red wine grapes grown in Arkansas are Chambourcin, grown commercially for its positive viticulture and enological quality, and Enchantment, a newer cultivar …

Ultrasound Mediated Tissue Growth In Bioinspired Scaffolds, Marco Fielder

Graduate Theses and Dissertations

Porous scaffolds mechanically stimulated with ultrasound are used for the treatment of bone conditions such as osteoporosis or traumatic bone injury. However, one current issue in these treatment techniques is designing a scaffold structure with a high structural integrity that also does not impede tissue growth. A larger ultrasound wave transmission would also allow more of a scaffold to receive mechanical stimulation from ultrasound. Controlling mesenchymal stem cell seeding of tissue scaffolds also has potential for developing optimal seeding patterns to maximize or control tissue growth in the scaffold based on an individual’s physiology. There is also a need for …

Data-Driven Deep Learning-Based Analysis On Thz Imaging, Haoyan Liu

Graduate Theses and Dissertations

Breast cancer affects about 12.5% of women population in the United States. Surgical operations are often needed post diagnosis. Breast conserving surgery can help remove malignant tumors while maximizing the remaining healthy tissues. Due to lacking effective real-time tumor analysis tools and a unified operation standard, re-excision rate could be higher than 30% among breast conserving surgery patients. This results in significant physical, physiological, and financial burdens to those patients. This work designs deep learning-based segmentation algorithms that detect tissue type in excised tissues using pulsed THz technology. This work evaluates the algorithms for tissue type classification task among freshly …

Hierarchical Structure And Material Integration For Electrocatalytic Co2 Reduction, Hamed Mehrabi

Graduate Theses and Dissertations

CO2 released by the combustion of fossil fuels is driving significant changes to the earth’sclimate. The natural cycle for removing CO2 from the atmosphere, namely photosynthesis, cannot keep up with the rate at which it is being added. Developing engineering approaches to remove CO2 from the atmosphere is becoming essential to reduce these effects. Removal leads to further issues of carbon sequestration and favorable CO2 reuse strategies, including the electrochemical transformation of recovered CO2 to useful products such as fuels and materials. Copper is an important electrocatalyst for the CO2 reduction reaction (CO2RR) because of its unique capability for producing …

Seasonal Patterns In Activity And Occupancy Dynamics Of The Imperiled Spotted Turtle (Clemmys Guttata), Ellery Vaughn Lassiter

Graduate Theses and Dissertations

Wetland ecosystems are often spatially patchy across a landscape and exhibit seasonal patterns in water levels, resulting in the need for aquatic wildlife to use several different wetland patches across a season. The ecology of semi-aquatic freshwater turtles is especially complex because individuals often move among a variety of habitats to meet life history needs and these habitat requirements often differ across a season. Understanding the temporal and spatial scale in which turtles move and distribute across the landscape is vital for effective management, especially in the face of continued habitat fragmentation and climate change. Thus, we sought to understand …

Nitrogen Management In Rice Under Suboptimal Soil Conditions, Payton Suzanne Rhea

Graduate Theses and Dissertations

In Mid-South rice (Oryza sativa, L.) production, nitrogen (N) fertilizer management for pureline varieties is most often recommended as a single preflood (SPF) or two-way split (2WS) application in a direct-seeded, delayed-flood system. Most of the N fertilizer is typically applied at the four- to six-leaf stage onto dry soil, and the second application, if necessary, into the floodwater during early reproductive growth stages (referred to as midseason). Environmental factors frequently prohibit growers from applying early N fertilizer under optimal dry soil conditions. A study was conducted to determine the best N fertilization management practices to utilize in rice when …

“What’S Belonging Got To Do With It?”: An Exploration Of Campus Racial Climate And Sense Of Belonging In Black Counseling Students Attending Predominately White Institutions In The North Atlantic Region, Erin Durrah

Graduate Theses and Dissertations

Diversity, equity, and inclusion (DEI) dialogues are raging across campuses throughout the U.S. with specific focus on the needs of Black student populations in the aftermath of the George Floyd, Breonna Taylor and Ahmaud Arbury murders. However, if the supportive spirit of the DEI initiatives is undermined by a hostile campus climate and local community, it may negatively impact the learning environment isolating the target population, while also effecting their potential for successful completion of their programs. The current qualitative study aims to explore the perceptions of belonging expressed by Black graduate students enrolled in Council for Accreditation of Counseling …

Surface-Driven Instabilities At Oil-Water Interfaces, Anelisse Claros Mendieta

Graduate Theses and Dissertations

Fluid-fluid interactions are such a wide area and can be observed in different scenarios such as geothermal systems, waterflooding of reservoirs, oil recovery, and water treatment processes. This thesis aims to deepen the understanding of fluid-fluid interactions which include Marangoni flows, charge related instabilities, and surface activity. This thesis studied the interactions of micrometer-sized droplets of an oil (toluene) with surfactant Di-(2-ethylhexyl) phosphoric acid (DEHPA) in the aqueous phase. One of the main goals is to understand several surface-driven instabilities and how those can be manipulated for future applications.Furthermore, this thesis aims to use these oil-surfactant droplets as a medium …

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …

Informal Education Experiences Of Black Women-Owned Healthcare Small Businesses In Mississippi, Timothy E. Lampkin

Graduate Theses and Dissertations

Small businesses are critical to the economic success of the United States, and several states, such as Mississippi, have a strong reliance on small business development. Through small, individually owned businesses, the overall economy is enhanced, and the quality of life for many is improved. A growing trend within the small business community is private ownership by Black women. This population segment has dramatically grown in their presence within business ownership, and it is necessary to describe elements of their success. The proposed research focuses on informal education as an enabler of this small business success. Informal education is a …

Electrical Modeling For Dynamic Performance Prediction And Optimization Of Mcpms Layout, Quang Minh Le

Graduate Theses and Dissertations

In recent years, the fast development of Multichip Power Modules (MCPM) packaging and Wide Bandgap (WBG) technology has enabled higher voltage and current ratings, better thermal performance, lower parasitic parameters, and higher mechanical reliability. However, the design of the MCPM layout is a multidisciplinary problem leading to many time-consuming analyses and tedious design processes. Because of these challenges, the design automation tool for MCPM layout has become an emerging research area and gained much attention from the power electronics community. The two critical objectives of a design automation tool for MCPM layout are fast and accurate models for design insights …

First-Principles Study Of Doping Effects On Ferroelectricity And On Rashba Spin Splitting, Zegnet Yimer Muhammed

Graduate Theses and Dissertations

In this dissertation, we have thoroughly studied the effect of chemical and charge dopingon ferroelectrics (PbTiO3 and BaTiO3) and Rashba type semiconductor (BiTeI). In the first project, We investigate the polar instability and soft modes in electron-doped PbTiO3 using linear-response density functional calculations. Because, metallicity and ferroelectric-like polar distortion are mutually non-compatible, and their coexistence in the same system is an intriguing subject of fundamental interest in the field of structure phase transition. However, it is unclear what mechanism may extend the limit of metallicity that allows polar distortion. We find that ferroelectric instability can remarkably sustain up to an …

Prediction Of Radiography Certification Examination Scores Using Astin’S Input-Environment-Output Model, Deanna Barymon

Graduate Theses and Dissertations

Numerous health profession fields, including radiology, have attempted to identify predictors of success on their respective credentialing exams. This preregistered study seeks to determine if available academic performance measures may predict radiography national certification examination scores and help educators identify students for remediation and support. The study will use the Astin Input-Environment-Output Model, which ascertains that student outcomes are a result of what they bring into an academic program and the environment experienced during the program. The non-experimental retrospective study will look at the 2018 to 2021 Arkansas State University radiography cohorts. Multiple regression will be used to determine if …

Understanding Perceptions Of Graduating Seniors From Rural Schools On Higher Education: A Preregistered Study, Desiree Denise Brake

Graduate Theses and Dissertations

The purpose of this qualitative case (preregistered) study is to interview rural young Americans, deeply explore how they think about higher education as they prepare for life beyond high school, and analyze how those views and perceptions translate into barriers or motivators to its pursuit. Rural Americans feel less optimistic about their financial futures, find it more difficult to find a job in their communities, and believe their children will have a lower standard of living than their parents when they reach their parents’ age (Morin, 2016). Rural students are more likely to graduate from high school than their urban …

“Monstrous Regiment Of Women”: Catholic Women’S Reactions To Reform In Sixteenth Century Scotland, Maeghan O'Conner

Graduate Theses and Dissertations

The Reformation in Scotland brought with it a substantial theological shift in perspective toward the place of women in religion, society, and politics. Women under Catholicism had established a pseudo-realm of agency as religious heads of the household and religious guidance from leaders outside their husbands and fathers, which changed drastically in the wave of Protestantism. The contemporary theological arguments most relevant in Scotland from John Knox and John Leslie are discussed to establish the basis of thought with which society would adjust women's roles. This thesis will ultimately emphasize the reactions and negotiations of Catholic women to this new …

A Comparison Of Student Final Grades In College Algebra Based On Face-To-Face And Online Course Modalities, Christopher Michael Lafata

Graduate Theses and Dissertations

As community colleges emerge from the COVID-19 pandemic there may be a tendency to rely on technology to facilitate more online coursework. Online education has been a fixture of higher education since the mid-1990s, but there’s always been a question as to whether it is effective as traditional, face-to-face coursework. This is especially important in College Algebra, already viewed as a barrier course for many students. If more students take College Algebra online, will the results be as good as students taking the course in a classroom? The purpose of this quantitative causal-comparative study is to identify the relationship between …

Disharmony Of The Soul: A Philosophical Analysis Of Psychological Trauma And Flourishing, Adam Blehm

Graduate Theses and Dissertations

In this dissertation I argue that psychological trauma hinders human flourishing by disrupting psychic harmony and hindering virtuous relationships. Given the negative symptomology of posttraumatic stress related disorders (i.e., PTSD) this conclusion may seem a bit obvious to some. However, making the case for trauma as a hindrance to human flourishing is more complicated than it may first appear.

First, in the extant literature, trauma as a concept tends to be unclear. In much of the empirical and philosophical literature, trauma can include a certain kind of event, experience, effect, or a combination of all three. Furthermore, because of practical …

Temporal Effects Of Acute Moderate Intensity Physical Activity On Working Memory Performance In Young Adults, Kimberly Loy Seibold

Graduate Theses and Dissertations

An ample amount of research suggests that increases in physical activity in young adults could help improve memory and cognitive functions which may aid in academic success (Johnson & Loprinzi, 2019; Perini et al., 2016). A sufficient working memory is critical to learning because it allows us to temporarily store and compare multiple informational items at one time to form a new concept or solve a problem (Cowan, 2013). The purpose of this study was to examine the temporal effects of acute moderate intensity physical activity on working memory in young adults. This study utilized a within-groups (repeated measures) cross-over …

Perceptions Of Beginning Secondary Alternatively Licensed Family And Consumer Sciences Teachers In Kansas: A Case Study, Jennifer S. Snell

Graduate Theses and Dissertations

Alternatively licensed Career and Technical Education teacher licensure programs have become a more conventional process for licensing new CTE teachers. Evidence from recent research supports that alternatively licensed teachers have a much greater teacher turnover rate than traditionally licensed teachers. This study focused on Family and Consumer Sciences education, which is part of the umbrella of CTE. There is limited research on new teacher training that specifically supports beginning alternatively licensed secondary FCS teachers in Kansas. This qualitative study examined the experiences of novice alternatively licensed secondary FCS teachers in Kansas who transitioned from the workforce with no previous teacher …

Multivariate Fairness For Paper Selection, Reem Alsaffar

Graduate Theses and Dissertations

Peer review is the process by which publishers select the best publications for inclusion in a journal or a conference. Bias in the peer review process can impact which papers are selected for inclusion in conferences and journals. Although often implicit, race, gender and other demographics can prevent members of underrepresented groups from presenting at major conferences. To try to avoid bias, many conferences use a double-blind review process to increase fairness during reviewing. However, recent studies argue that the bias has not been removed completely. Our research focuses on developing fair algorithms that correct for these biases and select …

Therapists’ Demonstrated Multicultural Competence In Treating Latinx Immigrants, Dulce Diaz Benitez

Graduate Theses and Dissertations

Studies suggest that health disparities occur when people from marginalized communities receive care that is inadequate based on their cultural needs (USDHHS, 2011). Multicultural competence (MCC) models have been proposed to provide a framework of the competencies that therapists should develop to work with multicultural populations (Sue et al., 1992). Researchers have questioned the validity of measures, which are mostly based on therapist self-report (Cartwright, 2008). The multicultural case conceptualization ability task has been used in previous studies as a measure of demonstrated cultural competence using a vignette to assess case conceptualization abilities (Ladany et al., 1997). However, it has …

Evaluation Of Cellulose Nanocrystal Inks And Their Structural Characteristics For 3d Bioprinting Of Customized Scaffolds, Patrick William Kuczwara

Graduate Theses and Dissertations

3D bioprinting of biological scaffolds requires control of the physicochemical properties of each unique structures. A promising material for control of properties is hydrogels, which can help create biomimetic scaffolds with controlled spatial arrangement of materials by integrating biological materials directly into layers during the bioprinting process. Nanocellulose offers a unique combination of properties including mechanical, biomimetic, and biocompatibility. These properties offer flexibility over the types, shapes, and applications of their printed hydrogel scaffolds, (i.e., tissue, drug, encapsulation). However, 3D bioprinting of nanocellulose-based hydrogels requires high loading percentages (i.e., >10 wt%) or chemical crosslinkers (i.e., bis(acyl)phosphane oxides (BAPO)). High solid …