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Understanding Radiation Resistance In Head And Neck Tumor Xenografts Using Diffuse Reflectance And Raman Spectroscopy, Sina Dadgar

Graduate Theses and Dissertations

Each year, 800,000 new patients are diagnosed with head and neck squamous cell carcinoma (HNSCC), a majority of whom are treated with a combination of daily fractions of radiation and weekly chemotherapy sessions for up to seven weeks. Current methods to evaluate treatment response of individual patients are limited to anatomical measurements of tumor burden using CT scan or MRI 4-8 weeks after completion of treatment. However, earlier knowledge of radiation-response prior to or at early days after commencement of therapy can aid oncologist with escalating and de-escalating treatment plans for exceptionally non-responding and responding patients. Such a knowledge can …

The Effects Of Solution Condition On Virus Filtration Performance, Fnu Namila

Graduate Theses and Dissertations

Virus filtration is an integral part of the downstream purification of mammalian cell culture-derived biotherapeutics to assure the viral safety of the products. Virus filtration membranes remove viruses based on a size-exclusion mechanism. Commercial parvovirus filers possess unique membrane structure and are designed to remove smaller non-enveloped parvoviruses with size 18-26 nm. However, some filters face issues, such as pre-mature fouling, the decline of filtrate flux, and reduction in virus retention. This doctoral dissertation focused on identifying the factors that influence the filtrate flux and the virus retention capability of commercial virus filters. The effects of solution pH and ionic …

Neogene And Quaternary Events Shaped Diversification And Speciation In Bhutanese Rheophilic Fishes Of The Family Nemacheilidae (Cypriniformes) And Sisoridae (Siluriformes), Karma Wangchuk

Graduate Theses and Dissertations

Biogeography of the Himalayan region [to include the Qinghai-Tibetan Plateau (QTP)] evolved over a ~30M year span, catalyzed by the collision of the Indian and Eurasian plates. The resulting uplift produced major ecological and climatic effects, that in turn drove the diversification of biodiversity. As a result, the QTP is designated as a global biodiversity hotspot particularly vulnerable to cumulative climatic effects, including shrinking distributions, declining numbers, and local extinctions. Understanding how the biodiversity within the Himalaya/ QTP was established and maintained is a necessary first step in prioritizing conservation efforts.

Fishes in global montane regions, such as the Himalaya, …

Optimizing Immersive Technology Condition For Measuring Consumer Perception And Acceptance Of Food Products, Shady Afrin Jeesan

Graduate Theses and Dissertations

Rapid advancement of immersive technologies is paving the way toward a new era in sensory and consumer science by enabling consumers to experience tasting of food samples in different environments, thus generating more realistic perception. However, little attention has been paid to developing a standardized and optimized methodology for conducting such sensory testing in an immersive environment. A variety of factors related to sensory testing in an immersive environment may significantly modulate consumer perception and acceptance of foods. Therefore, this thesis study aimed to optimize protocols related to sensory testing using immersive technology. In this thesis study, participants were asked …

Multi-Proxy Provenance Evaluation Of The Stevens Sandstone, San Joaquin Basin, California, Charles Adam Ball

Graduate Theses and Dissertations

The Stevens sandstone is a prolific hydrocarbon reservoir in the southern San Joaquin Basin that has produced greater than five billion barrels of oil equivalent and represents an important exploration target. The San Joaquin basin has a complex depositional and structural history related to the overprinting of a Mesozoic-Paleogene forearc basin by transtension and transpression along the San Andreas fault system that presently borders the southwestern side of the basin. The Stevens sandstone consists of quartzo-feldspathic, deep-water turbidite deposits and is primarily confined within the subsurface of the southern San Joaquin basin. Due to this mode of deposition and the …

Design Of A 350 Kw Silicon Carbide Based 3-Phase Inverter With Ultra-Low Parasitic Inductance, Matthew Feurtado

Graduate Theses and Dissertations

The objective of this thesis is to present a design for a low parasitic inductance, high power density 3-phase inverter using silicon-carbide power modules for traction application in the electric vehicles with a power rating of 350 kW. With the market share of electric vehicles continuing to grow, there is a great opportunity for wide bandgap semiconductors such as silicon carbide (SiC) to improve the efficiency and size of the motor drives in these applications. In order to accomplish this goal, careful design and selection of each component in the system for optimum performance from an electrical, mechanical, and thermal …

"Some Kind Of Socialist:" Lee Hays, The Social Gospel, And The Path To The Cultural Front, Elizabeth Withey

Graduate Theses and Dissertations

In 1939, with sixty-five dollars and twenty pages of Commonwealth Labor songs, Lee Hays, youngest son of a Methodist minister, hitchhiked thirteen hundred miles from Mena, Arkansas, to New York City where he found stardom in the Folk Revival movement, first, as a founder of the Almanac Singers then the Weavers. Hays’ biographer Doris Willens and others, viewing Hays’ unabashed socialism, ribald humor, penchant for beer, brandy, and cigarettes as induced by the childhood trauma of his father’s death, argue Hays rejected his father’s beliefs: replacing religion with radical politics. This thesis, in contrast, argues Hays’ upbringing immersed in contradictions …

Antioxidant Properties And Anti-Cancer Effects Of Polyphenols In Sweetpotato Leaves, Josue Bolanos

Graduate Theses and Dissertations

Although the root is widely consumed, sweetpotato leaves (SPL) are often discarded and are only consumed in a few countries. In the United States, SPL consumption is limited to private gardens, particularly in the Southeastern United States. Not only are SPL a good source of nutrients such as vitamins and minerals, but they also contain polyphenol compounds including the caffeoylquinic acid derivatives and carotenoids such as lutein. Several studies have shown the polyphenol contents and antioxidant capacities of SPL, which vary based on year and variety, while few studies have shown anti-colon cancer effects of SPL. Therefore, this study investigated …

Projecting Water Available For Irrigation Use And Identifying Water Supply Stress Under Climate Change Scenarios In Selected U.S. Fruit And Vegetable Production Regions, Andrew Shaw

Graduate Theses and Dissertations

Climate change affects water resources differently across geospatial regions in the United States (U.S). There is a concern of how water availability will be affected by changes in long-term temperature and precipitation patterns, specifically in major production regions for eight fruit and vegetable crops. The effects on surface water available for irrigation use and supply stress in five regions containing 31 Agricultural Statistics Districts (ASDs) were assessed. The Water Supply Stress Index Model was used and modified to project water available for irrigation use across nine climate scenarios driven by historical data, five General Circulation Models, two population scenarios, and …

Quantifying Workability, Compactability, And Cohesion Gain Of Asphalt Emulsion Cold In-Place Recycling, Sadie Casillas

Graduate Theses and Dissertations

To maximize the life and quality of a pavement, proper maintenance and rehabilitation are essential. Strategies for pavement rehabilitation with many sustainable benefits are pavement recycling. This dissertation focuses on two types of in-situ pavement recycling: Cold in-place recycling (CIR) stabilized with asphalt emulsion and full depth reclamation (FDR) stabilized with asphalt emulsion or foamed asphalt. One white paper (Chapter 2), two accepted peer reviewed journal articles (Chapters 3 and 4), and one submitted peer reviewed journal article (Chapter 5) are presented in this document to create better understanding of the unique material characterization of asphalt emulsion cold recycled materials, …

Commodity-Based Freight Activity On Inland Waterways Through The Fusion Of Public Datasets For Multimodal Transportation Planning, Magdalena I. Asborno

Graduate Theses and Dissertations

Within the U.S., the 18.6 billion tons of goods currently moved along the multimodal transportation system are expected to grow 51% by 2045. Most of those goods are transported by roadways. However, several benefits can be realized by shippers and consumers by shifting freight to more efficient modes, such as inland waterways, or adopting a multimodal scheme. To support such freight growth sustainably and efficiently, federal legislation calls for the development of plans, methods, and tools to identify and prioritize future multimodal transportation infrastructure needs. However, given the historical mode-specific approach to freight data collection, analysis, and modeling, challenges remain …

Dissecting The Cellular Control Of Septin Organization In A Global Cereal Killer, Nawaraj Dulal

Graduate Theses and Dissertations

Rice blast disease, caused by the filamentous fungus Magnaporthe oryzae, destroys sufficient rice each year to feed 60 million people, and is a serious threat to global food security. A wheat-adapted lineage of M. oryzae now poses threat to global wheat production. Rice blast disease is currently controlled using limited fungicides, and the emergence of fungicide resistance within M. oryzae populations is a growing concern. There is a pressing need to identify new classes of fungicides to control the disease, which requires better understanding of the basic biology of the pathogen. To establish disease, M. oryzae forms a specialized dome …

The Role Of Designers In Promoting Healthy Masculinity With An Approach To Stopping Violence Against Women And Girls, Fatemeh Abolbashari

Graduate Theses and Dissertations

While awareness about violence against women and girls is growing, there is still a lack of evidence about what changes behavior to prevent it from happening. As a graphic designer, I wanted to find the root problem of this issue and work towards a solution. Through my research and questioning, I concluded that this problem begins with men’s thoughts on hierarchy, language, and behavior, and supported by a prevalence of toxic masculinity in men’s culture.

Where does this violence come from? What has society done to raise this kind of man? Violence against women and girls is being couched in …

Scenic Design For “Topdog Underdog”, Austin Aschbrenner

Graduate Theses and Dissertations

The 2019 production of Topdog/Underdog by Suzan-Lori Parks at the University of Arkansas was produced with a guest director who, throughout the process of the production, experimented with the typical perception of the Pulitzer Prize winning play and added conceptual spins to help open the eyes of the mostly small town and rural based audience. This thesis will explore the various elements of this particular production and which of these elements contributed to exploring the depths of Topdog/Underdog.

This document will analyze the design process of the University of Arkansas’s production of Topdog/Underdog, and will analyze specific design choices which …

Investigation Of The Role Of Heparin-Binding Pocket In Amyloid Fibrils Formation Of Fgf-1, I Gusti Ayu Agung Septiari

Graduate Theses and Dissertations

Human acidic fibroblast growth factor (aFGF/hFGF-1) is one of the promising molecules to be investigated to generate an in-depth understanding of the pathological mechanism of Alzheimer's disease (AD) neurodegenerative disorder characterized by the presence of amyloid fibrils. Some in vivo and human brain tissue studies proved the correlation of high-level expression of FGF-1-induced neuroinflammation and the occurrence of AD. The presence of amyloid fibrils as a hallmark of AD can be related to the generic property of the proteins to form amyloid fibrils; High level of FGF-1, in this case, may contribute to the formation of amyloid fibrils. As a …

The Scenic Design Of "A Little Night Music", Kathleen Holmes

Graduate Theses and Dissertations

A Little Night Music by Hugh Wheeler and Stephen Sondheim was produced by the University of Arkansas Department of Theatre in 2018-2019 academic school year. The scenic design process entailed a series of private meetings, design meetings, independent research, and analysis that all culminated into a full scenic design package. The show itself has many locations that quickly transition into one another. It was my challenge as the designer to cohesively design the scenery so that it could be transitioned easily and in time with the music. The major themes of the show that I based the design around were …

Election Day — Documentary, John Thomas Tarpley

Graduate Theses and Dissertations

Election Day is a three-channel documentary chronicling the places, personalities, and tone of Little Rock, Arkansas, during its titular midterm Election Day in November 2018. Throughout the course of the day, the film branches across the city, capturing mini-narratives, bits of conversation, and tableau of civic activity in the public sphere. It is less concerned with the quantitative facts of the day as it is with conveying the transitory social expressions and moods of a modern, southern city on a uniquely American day. This project represents my continued documentary interest in creating inclusive, contemporary local portraits and counter-historical chronicles of …

The Adult Public’S Perception Of The Utility Of Play Therapy, Margaret L. Hindman

Graduate Theses and Dissertations

Children communicate through symbolism and play as toys are children's words and play is their language (Landreth, 2012; Oaklander, 1988; Piaget, 1951; Ray, 2016). Play therapists facilitate developmentally appropriate support for children (Landreth, 2012). Often parents are unaware of the importance of play in children’s counseling (Brumfield & Christensen, 2011; Landreth, Bratton, Kellam, & Blackard, 2006).

Since adults often make decisions for children, it is important to know adults’ perceptions of play therapy utility. There is little research on parents’ knowledge of mental health services especially research specific to play therapy (Gallo, Comer, & Barlow, 2013; O’Connor & Langer, 2018). …

Relationship Marketing And Intercollegiate Sport Promotion, Alison Fridley

Graduate Theses and Dissertations

The first article, a case study on a NCAA Division I Power Five university in the southeastern United States, employed a case study framework, explored target markets and exposure techniques through both the planned behavior theory and social identity theory theoretical lenses. This study aimed to better understand how university students and booster club members identify as a social group. The data emerged into four distinct themes, including communication, social interaction, connection, and hospitality. The findings suggested booster club members are primary fans and help the team generate fan interest. The importance of sociability was clear and the implications for …

Web Annotation In English Language Arts: Online Dialogue As A Platform To Support Student Comprehension Of Texts, Jonathan B. Allred

Graduate Theses and Dissertations

This study explores how web annotation—through a process of online reading, writing in the margins, and replying to others’ comments—influences student dialogue in ways that research suggests are associated with improved comprehension. Viewing data through a dialogic lens, and using a qualitative, multiple case study design to observe two high school English Language Arts teachers and their students, this inquiry was guided by the following research questions: (a) How do English Language Arts teachers use web annotation to support student comprehension of texts? (b) To what extent, if any, does web annotation appear to support student comprehension of texts? and …

Distress Tolerance In Relation To Treatment Persistence, Engagement, And Improvement In An Exposure-Based Treatment For Sexually Abused Incarcerated Women, Ilana S. Berman

Graduate Theses and Dissertations

Incarcerated populations are disproportionately affected by traumatic experiences and symptoms of posttraumatic stress disorder (PTSD). Many effective treatments for PTSD utilize exposure-based techniques which require engaging with emotionally distressing content. However, individuals with PTSD and low distress tolerance (DT) are more likely than those with PTSD and higher DT to engage in avoidant coping behaviors and have relatively high treatment attrition rates in general. This study explored relations between DT and treatment persistence, engagement, and improvement in incarcerated women (N = 85) enrolled in an 8-week exposure-based sexual assault recovery group at a minimum-security prison. I hypothesized lower baseline levels …

Remote Sensing And Gis Study Of Hazards And Risks In East Africa, Hafid Nanis

Graduate Theses and Dissertations

East Africa encompasses numerous developing countries and involves one of the most active continental rifts on Earth; namely, the East African Rift System. This region is prone to diverse geohazards due to its geographical location at the plate boundary. Several damaging events had happened across the region and more are predicted to occur in the near future. Therefore, it is crucial to investigate, assess, and forecast natural hazards and potential risks in the region. In this dissertation, remote sensing and Geographic Information System (GIS) were employed to conduct three independent studies focused on assessing geohazards in east Africa. Each study …

An Experimental Investigation Of Liquid Hydrocarbons In A Simulated Titan Environment, Kendra Farnsworth

Graduate Theses and Dissertations

Saturn’s moon, Titan, has surface conditions (89–94 K, 1.5-bar atmosphere) that permit lakes of methane, ethane, and dissolved atmospheric nitrogen. The effects of atmospheric nitrogen on methane-ethane liquid properties is poorly understood, leading to uncertainty in Titan modeling. I address this question by experimentally investigating the physical properties of methane-ethane liquids under a 1.5-bar nitrogen atmosphere in a simulated Titan environmental chamber.

Chapter 1 addresses nitrogen dissolution kinetics in Titan’s liquid hydrocarbons. I found an exponential increase in nitrogen quantity and diffusion coefficients with increasing methane mol%. I find that Titan’s liquids are likely not saturated in nitrogen, with dissolution …

The Defense Of Principates: The English Appropriation Of Marsilius Of Padua's 'Defensor Pacis', Nathan Harkey

Graduate Theses and Dissertations

Marsilius of Padua’s Defensor pacis is widely thought to be one of the most important texts to emerge in late medieval Europe. Initially purposed as a defense of Holy Roman Emperor Ludwig IV’s rights against the claim of the papacy’s claim to possess a ‘plenitude of power’, Defensor pacis is one of the most sophisticated arguments against the centuries of abuse of papal authority. Marsilius, though condemned as a heretic during his lifetime, remains a pivotal figure for medieval and early modern European historians, and is perhaps best remembered by the ways that his ideology influenced subsequent generations of political …

Design Of Control System With Feedback Loop For A Pulsatile Pump, Ian Scott Sanders

Graduate Theses and Dissertations

This paper describes the design and implementation of a closed-loop proportional, integral, differential (PID) control system for a custom in-house pulsatile pump apparatus for the University of Arkansas Biomedical Department. The control system is designed to control a MOONS’ PL34HD0L8500 hybrid stepper motor using a dual H-bridge motor driver network with four pulse-width modulated (PWM) inputs to drive a pulsatile pump apparatus at motor stepping frequencies up to 2kHz. The speed of the motor is controlled from a pressure profile transmitted from an external source over RS-232 communication that specifies the motor speed, number of datapoints, and an array of …

A Suspected Democratic Regiment: The Fourth New Hampshire Volunteers In The American Civil War, Eric Paul Totten

Graduate Theses and Dissertations

The Fourth New Hampshire Volunteer Infantry was suspected of being a Democratic regiment due to the intense partisanship of the antebellum and Civil War era. The political socialization of New Hampshire’s citizens divided communities and fostered animosity towards political opponents. The unit’s recruits came from regions that were political battlegrounds and contained a large number of Irish immigrants. The intemperate and disorderly conduct of the officers and men of the Fourth during the Port Royal expedition seemingly confirmed the suspicions of civilians on the home front. The arrest of Colonel Louis Bell by Major General David Hunter led to further …

Models For Data Analysis In Accelerated Reliability Growth, Cesar Alexander Ruiz Torres

Graduate Theses and Dissertations

This work develops new methodologies for analyzing accelerated testing data in the context of a reliability growth program for a complex multi-component system. Each component has multiple failure modes and the growth program consists of multiple test-fix stages with corrective actions applied at the end of each stage. The first group of methods considers time-to-failure data and test covariates for predicting the final reliability of the system. The time-to-failure of each failure mode is assumed to follow a Weibull distribution with rate parameter proportional to an acceleration factor. Acceleration factors are specific to each failure mode and test covariates. We …

Elucidating Collagen Degradation Synergy Between Col G And Col H From Hathewaya (Clostridium) Histolytica And Identifying Novel Structural Features In Hpt And Rec Domains From Vars Histidine Kinase In V. Alginolyticus, Perry Caviness

Graduate Theses and Dissertations

In this research the mechanisms by which Hathewaya (Clostridia) histolytica collagenases are secreted and work together to degrade collagens are investigated. While H. histolytica collagenases Col G and Col H have similar multi-domain structures the difference in number of and orientation of the domains hint that the two target different regions in collagen. Study small angle x-ray scattering (SAXS) was used to give a low-resolution envelope of full-length Col G and Col H and Col G/Col H non-catalytic domains bound to a collagen-like peptide (mini-collagen). SAXS derived envelopes along with structural information was used to tease out the mechanisms by …

The Relationship Between Leadership Practices And Organizational Commitment Of Telecommunicators, André Lanier

Graduate Theses and Dissertations

The performance of 9-1-1 telecommunicators can mean the difference between life and death for the person on the other end of a phone. Effective leadership is critical to the success of the public safety answer point (PSAP) and the organizational commitment of the 9-1-1 telecommunicator. Bass and Riggio’s (2006) Full Range of Leadership Theory (FLRT) is the basis for the current study. The FRLT covers leadership styles from laissez-faire to transformational (Matikainen, 2019).

The purpose of conducting the study was to identify and describe the 9-1-1 telecommunicator’s organizational commitment based on the PSAP leadership categories. The study made use of …

Effects Of Supplementing Crystalline L-Valine And L-Isoleucine And A Novel Threonine Biomass In Reduced Crude Protein Diets Fed To Broilers, Derrell Trevor Lee

Graduate Theses and Dissertations

Poultry nutritionists continue to identify methods to lower feed price without compromising broiler growth performance, processing yields, or animal well-being. A common approach is to reduce dietary crude protein (CP), the second most expensive component in a broiler diet. Subsequently, reducing CP will reduce the inclusion levels of intact protein sources (e.g., soybean meal [SBM]), which can be accomplished by supplementing individual amino acids (AA). This methodology not only reduces diet cost, pending if feed-grade AA are more economical, but can contribute to improving broiler health and environmental sustainability. Therefore, two experiments were conducted to evaluate individual feed-grade AA in …