Digital Commons Network^™

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 …

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 …

Delaying College For Domestic Civic Service: The Gap Year Experiences Of City Year Americorps Alumni, Christopher John Bryson

Graduate Theses and Dissertations

Over the past decade the concept of taking a gap year has become mainstream in the US. This idea of delaying enrollment, or taking a break from college, before beginning a bachelor’s degree, has gained popularity, especially as the cost of attendance in higher education has soared and the burden of paying for it has been placed on the student as the consumer. Similarly, the sought-after gap year experiences offered in the private sector are often costly. With the rising popularity of gap years, it is important to identify experiences that are accessible to a wide variety of backgrounds and …

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 …

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 …

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 …

Hybrid Multilevel Converters With Internal Cascaded/Paralleled Structures For Mv Electric Aircraft Applications, Fei Diao

Graduate Theses and Dissertations

Using on-board medium voltage (MV) dc distribution system has been a megatrend for next-generation electric aircraft systems due to its ability to enable a significant system mass reduction. In addition, it makes electric propulsion more feasible using MV power electronic converters. To develop high-performance high-density MV power converters, the emerging silicon carbide (SiC) devices are more attractive than their silicon (Si) counterparts, since the fast switch frequency brought by the SiC can effectively reduce the volume and weight of the filter components and thus increase the converter power density. From the converter topology perspective, with the MV dc distribution, the …

The Impact Of Video-Taped Social Modeling On Alcohol Outcome Expectancies Of Young Adults And The Role Of Social Anxiety, Kyle Kevin Jackson

Graduate Theses and Dissertations

Alcohol outcome expectancies (AOEs) represent people’s ideas about the effects of alcohol (Fromme, 1993). Positive AOEs particularly have been identified as a potential risk factor for hazardous drinking (e.g., Brown et al., 1985). The exact mechanisms that modify AOEs are not fully understood. Further, people higher in social anxiety may be especially receptive to social modeling due to attentional bias shift towards others in social contexts (Rapee & Heimberg, 1997). The current study examined how social anxiety and social modeling associate with AOEs. It was hypothesized that 1) those in the social modeling treatment condition would have higher social anxiety-adjacent …

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 …

The Binding Of The Micronutrient Transition Metals To The Alkylation Products Of Chemical Warfare Agent, Sulfur Mustard, And Thiols, Potentially Giving New Understanding To Physiological Effects Of Exposure And Increased Toxicity, Colin O'Donnell

Graduate Theses and Dissertations

Model compounds, 3,6,9-trithaiundecane-1,11-dicarboxylic acid (TTDPA), 2,5,8-trithianonane-1,9-dicarboxylic acid (TTDAA), and 1,11-diamide-3,6,9-trithiaundecane (TTDAce), closely related to the adducts formed by cysteine alkylation of the chemical weapon, sulfur mustard, were synthesized. It is shown that TTDPA forms complexes with key metal micronutrients: copper, nickel, cobalt, manganese, and zinc. Though the strength of binding to TTDPA varies, the complexes in many cases precipitate from solution. All metals produced a visible precipitate upon interaction with TTDPA under the conditions tested, however only Cu2+, Mn2+, and Zn2+ produced enough to be measured. The mass of formed precipitate seemed to peak at an equimolar ratio of TTDPA …

Diagnosing Excess Nitrogen In Rice Using Post-Season Tissue Samples, Kyle Hoegenauer

Graduate Theses and Dissertations

Proper nitrogen (N) management in rice production can be difficult to achieve without the aid of tools such as soil and tissue tests. There are no tests currently available to rice producers that determine whether N has been managed properly throughout the season or that detect instances of over fertilization. Rice stalk samples were collected from N response trials within 3 days of harvest from the primary Arkansas rice growing region in 2016-2018. Stalk samples were analyzed for N concentration through a KCl extraction and spectrofluorometric quantification. Samples analyzed with leaf material intact contained statistically different N concentrations than samples …

Delineating Field Variation Using Apparent Electrical Conductivity In An Ozark Highlands Agroforestry System, Shane Reid Ylagan

Graduate Theses and Dissertations

Little to no work has been conducted assessing field variability using repeated electromagnetic induction (EMI) apparent electrical conductivity (ECa) surveys in agroforestry (AF) systems within regions similar to the Ozark Highlands. The objectives of this thesis were to identify i) spatiotemporal ECa variability; ii) ECa-derived soil management zones (SMZs); iii) correlations among EMI-ECa and in-situ, sentential-site soil properties; iv) whether fewer, EMI-ECa surveys could be conducted to capture similar ECa variance as mid-monthly EMI-ECa surveys; v) correlations between ECa and forage yield, tree growth, and terrain attributes based on plant (forage and tree) species, and fertility treatments, and ECa-derived SMZs, …

Deciphering Surfaces Of Trans-Neptunian And Kuiper Belt Objects Using Radiative Scattering Models, Machine Learning, And Laboratory Experiments, Al Emran

Graduate Theses and Dissertations

Decoding surface-atmospheric interactions and volatile transport mechanisms on trans-Neptunian objects (TNOs) and Kuiper Belt objects (KBOs) involves an in-depth understanding of physical and thermal properties and spatial distribution of surface constituents – nitrogen (N2), methane (CH4), carbon monoxide (CO), and water (H2O) ices. This thesis implements a combination of radiative scattering models, machine learning techniques, and laboratory experiments to investigate the uncertainties in grain size estimation of ices, the spatial distribution of surface compositions on Pluto, and the thermal properties of volatiles found on TNOs and KBOs. Radiative scattering models (Mie theory and Hapke approximations) were used to compare single …

Evidence Of Emotional Intelligence In College Presidents’ Public Writing: Does Their Emotional Intelligence Change Over Time?, Karen Powers Liebhaber

Graduate Theses and Dissertations

Higher education (HIED) presidents face a wide variety of competing demands and pressures. High emotional intelligence (EI) has been found to be effective in good leadership, but few studies exist which examine HIED presidents’ EI. This quantitative growth model study attempted to expand the understanding of EI and its source of change among HIED presidents. Several conceptualizations link together in this study to better understand HIED presidents’ EI. First, higher EI has been linked to strong leadership and strong communication. Studies show EI can change over time and EI is associated with certain demographic factors. Further, language, particularly written language, …

Efficient Hierarchical Space-Time Models For Large Areal Datasets With Application To Forest Inventory Mapping Using Remote Sensing Imagery, Md Kamrul Hasan Khan

Graduate Theses and Dissertations

The focus of this dissertation is development of a novel hierarchical framework, that can be used for predictive modeling of Forest Inventory and Analysis (FIA) data over large regions. This dissertation has two significant contributions. Based on a study region in north-central Wisconsin, we analyze satellite imagery, along with a sample of national forest inventory field plots, to monitor and predict changes in forest conditions over time. The auxiliary data from the satellite imagery of this region are relatively dense in space and time, and can be used to learn how forest conditions changed over that decade. However, these records …

Schools Of Rivals: Physicians, Fights, And Reform In Nineteenth-Century, Southern Medical Education, Laura Elizabeth Smith

Graduate Theses and Dissertations

While the professionalization of medicine in the nineteenth century hinged on community trust, faculty at Southern medical schools hurt their own reputations with their proprietary schools, their public rivalries, and their competition for clinical material and cadavers. Attempts to regulate medical schools also became fodder for doctors to slander each other, all arguing that their methodologies and their schools were superior. This fierce competition resulted from the constant need to lure in more students to ensure these schools’ survival, but it hurt the reputation of doctors as a whole, convincing the public that one doctor seemed just as incompetent and …

Reliability Enhancing Control Algorithms For Two-Stage Grid-Tied Inverters, Yuheng Wu

Graduate Theses and Dissertations

In the photovoltaic (PV) generation system, two types of grid-tied inverter systems are usually deployed: the single-stage grid-tied inverter system and the two-stage grid-tied inverter system. In the single-stage grid-tied inverter system, the input of the inverter is directly connected to the PV arrays, while an additional dc-dc stage is inserted between the PV arrays and the dc-ac inverter in the two-stage design. The additional dc-dc stage could provide a stable dc-link voltage to the inverter, which also enables new design possibilities, including the multi-MPPT operation and solar-plus-storage application. Thus, the two-stage grid-tied inverter has been widely used in the …

Effect Of Varying Amounts Of Sandstone On The Performance Of Asphalt Mixtures In Arkansas, David Murphy

Graduate Theses and Dissertations

There are many different species and subspecies of aggregate used across the state of Arkansas, and the rest the country. However, it cannot be presumed that the amount and type of these aggregates will be compatible with the commonly used asphalt binder of an area; this can lead to performance issues and premature pavement damage. It has been suspected in Arkansas that an excessive amount of sandstone in asphalt mixtures may be a culprit of some of these premature pavement damage issues, especially regarding the moisture susceptibility of a pavement. This study aimed to analyze the performance effects of using …

Analysis Of Seismicity And Related Seismic Risk In Muslim Countries: Case Studies From Afghanistan And Pakistan, Ikramuddin Bahram

Graduate Theses and Dissertations

How communities respond to a natural hazard is influenced by how they perceive it. This dissertation evaluated the gap between intent and action regarding earthquake hazards in Muslim countries with a focus on Afghanistan and Pakistan. Cultural biases provided predictions of risk perceptions and risk-taking preferences that were often more powerful than measures of knowledge and experience. In Muslim communities, perception of risk was influenced by the teachings of Islam and related rituals, traditions, and culture.

This study evaluated the seismicity and earthquake hazard in Afghanistan and Pakistan. Assessments of seismic risk and perception of danger were conducted to examine …

Assessing Consumer Demand, Producer Profitability, And The Environmental Impacts Of Conservation Agriculture Adoption In Sub-Saharan Africa, Willy Byamungu Mulimbi

Graduate Theses and Dissertations

This dissertation explores three aspects of conservation agriculture (CA) in the Sub-Saharan African region (SSA). The first article examines the demand side of CA and explores whether urban maize (Zea mays L.) consumers in the Democratic Republic of the Congo (DRC) would be willing to pay a premium for CA-produced maize flour. The second article estimates the effects CA provides to adopters and their farms in smallholder farming systems in the DRC, focusing on changes in soil properties and cowpea (Vigna unguiculata) yields. The final article uses a Life Cycle Assessment (LCA) approach to monetize the environmental impacts of adopting …

Data-Driven Research On Engineering Design Thinking And Behaviors In Computer-Aided Systems Design: Analysis, Modeling, And Prediction, Molla Hafizur Rahman

Graduate Theses and Dissertations

Research on design thinking and design decision-making is vital for discovering and utilizing beneficial design patterns, strategies, and heuristics of human designers in solving engineering design problems. It is also essential for the development of new algorithms embedded with human intelligence and can facilitate human-computer interactions. However, modeling design thinking is challenging because it takes place in the designer’s mind, which is intricate, implicit, and tacit. For an in-depth understanding of design thinking, fine-grained design behavioral data are important because they are the critical link in studying the relationship between design thinking, design decisions, design actions, and design performance. Therefore, …

The Office Of Possible Projects, Juliette Walker

Graduate Theses and Dissertations

This writing is a companion to the MFA thesis projects that I presented in the Spring 2022 semester at the University of Arkansas in Fayetteville, Arkansas. My thesis work did not exist as a singular, solo exhibition in a traditional gallery space like it did for most of the artists in my graduating cohort; rather, I completed three different but substantial and interrelated projects, many of which occurred outside of traditional art spaces: the Office of Possible Projects at the Fayetteville Public Library, the Cake Stand Biennale which took place across the city of Fayetteville, Arkansas, and the office of …

Mitochondrial Dna Diversity, Parasite And Pathogen Occurrence, And A Potential Disease Vector In Managed And Unmanaged Honey Bee, Apis Mellifera L. Populations, Dylan Cleary

Graduate Theses and Dissertations

The western honey bee, Apis mellifera L., is a globally important pollinator plagued by several harmful stressors impacting colony health and survival. At least eight A. mellifera subspecies were imported and continue to be the genetic ancestors of U.S. honey bee populations today. Successive genetic bottle-neck events have led to reduced genetic diversity in U.S. honey bees. First, the subset of subspecies imported into the U.S. represents only a third of A. mellifera subspecies. Next, the parasitic varroa mite reduced managed and feral populations. Third, ongoing breeding practices have selected for traits from a single genetic lineage and bred from …

Investigations Into Flange Surface Friction Effects On Shear Stud Load Transfer In Composite Bridge Girders, Callie Clark

Graduate Theses and Dissertations

Composite bridge behavior is commonly achieved through headed shear studs welded tothe steel girder flange and embedded in the concrete deck. Current AASHTO provisions for estimating demands on shear studs during service-level loading consider only bearing load transfer, neglecting adhesion bonding and friction load transfer between the concrete deck and girder flange. Quantifying alternative load transfer mechanisms across the steel-concrete interface may result in improved steel bridge economy by reducing the number of studs required in a composite girder design. This study investigates the effects of flange surface friction (considering various coatings) on resulting stud demands using both experimental testing …

Initial Exploration Of Reduced Gyrations For Arkansas Asphalt Mix Designs, Jocie L. Baker

Graduate Theses and Dissertations

The most common distresses in asphalt pavement are cracking and rutting. These distresses plague almost every asphalt roadway in the world. Finding ways to mitigate these distresses will improve the performance of asphalt pavements. One way to combat the premature cracking of asphalt in the field is to ensure there is enough asphalt binder within the mix. This will help the flexibility of the asphalt undergoing large loads and deformation. However, it is widely accepted that mix designs across the country lack the appropriate amount of asphalt binder in their mixes, causing dry mix designs that are subject to cracking …

Through The Heart Of The City: Interstates And Black Geographies In Urban America, Airic Hughes

Graduate Theses and Dissertations

Federal urban renewal projects changed the landscape of numerous American cities throughoutthe twentieth century. Many of these projects worked cohesively in tandem with discriminatory urban planning policies such as redlining. The conclusions of this project demonstrate how U.S. Interstate 630 (I-630) intentionally re-segregated Arkansas' capital city, following the U.S. Supreme Court’s 1954 national desegregation order and the infamous desegregation of Little Rock Central High School in 1957. I further contend that I-630 was constructed using the racialized language and tactics of urban renewal and was fundamental to improving Little Rock’s national reputation by purging the city's social memory and legacy …

Closing The Gender Gap In Entrepreneurship Education, Carolyn J. Rodeffer

Graduate Theses and Dissertations

Entrepreneurship education in higher education has been cited as a key strategy in filling the entrepreneurship talent pool, preparing students with the skills and confidence needed to start new ventures (Westhead & Solesvik, 2016). However, outcomes of entrepreneurship education for female students are less positive than for their male counterparts (Shinnar et al., 2012; Westhead & Solesvik, 2016; Wilson et al., 2007). Working within the frameworks of Bandura’s self-efficacy theory (1977), Azjen’s theory of planned behavior (1991), and Steele and Aronson’s stereotype threat theory (1995), this quantitative study utilized an experimental research design to assess the impact of role model …