Digital Commons Network^™

An Experimental Test Of The Effects Of Sleep Deprivation On Approach Behavior, Rebecca L. Campbell

Graduate Theses and Dissertations

Emotion regulation and sleep have been identified as mechanisms that may be involved in the development and maintenance of many mental health disorders. However, there has been little research into the relation between sleep and emotion regulation. To address this gap in knowledge, a novel study was conducted. We hypothesized that sleep deprived individuals would demonstrate less approach behavior toward a negatively valenced stimulus, as well as increased self-reported avoidance, compared to a control group. To test this, a randomized controlled experiment using a behavioral measure of approach and a self-report measure of avoidance was conducted. Fifty-two healthy individuals ages …

The Strategic Disclosure Of Currency Headwinds And Tailwinds, Kevin Butler

Graduate Theses and Dissertations

In this study, I examine whether companies are more likely to disclose revenue growth adjusted to remove the effects of foreign currency fluctuations (constant-currency revenue growth rates) when currency fluctuations decrease revenue growth (i.e., there is a currency headwind) than when currency fluctuations increase revenue growth. Public companies increasingly cite non-GAAP performance metrics when announcing earnings. While regulators see value in non-GAAP reporting, they continue to express concern that it is carried out inconsistently and in a misleading manner. Because the disclosure of constant-currency revenue growth is discretionary, companies have an incentive to strategically disclose it only when it benefits …

A Comparative Ecological Study Of Limestone And Dolomite Glades In The Ozark Mountains Of Northwest Arkansas, Brittney Booth

Graduate Theses and Dissertations

Glades are one of the many habitats that exist in the Arkansas Ozarks and contribute to the overall biodiversity of the state of Arkansas. For this study, five dolomite glades and five limestone glades in the Ozarks of northwest Arkansas were studied from March to October in the years 2017 and 2018 to determine the similarities or differences that might be present. One hundred and fifteen vascular plant taxa were documented in the dolomite glades and one hundred and three vascular plant taxa were documented in the limestone glades. Forty-six vascular plant taxa were unique to the dolomite glades and …

Peer Acceptance In The Lunchroom And Children’S Internalizing Symptoms, Jake Steggerda

Graduate Theses and Dissertations

There is evidence to suggest that the context of the school lunchrooms provides children with rich opportunities for enhancing or hampering the quality of their relationships (Craig, Gregus, Elledge, Pastrana, & Cavell, 2016; Steggerda et al., in preparation). Although past research has linked children’s peer acceptance to their level of internalizing symptoms, few studies have examined peer acceptance within the lunchroom context. This study extends that work by examining associations between lunchroom peer acceptance (assessed via self- and peer-reports) and children’s internalizing symptoms. Participants were 676 fourth-grade students (50.7% female; 42.7% Hispanic/Latino, 30.3% White, 10% Pacific Islander, and 17% other) …

Instagram And Eating Disorders: An Empirical Study Of The Effects Of Instagram On Disordered Eating Habits Among Young Girls, Katherine Wayles

Graduate Theses and Dissertations

Scholars have studied the relationship between body dissatisfaction and social media use, particularly focusing on young women as vulnerable consumers. Many studies concentrate on the amount of media consumed, rather than the specific activities and behaviors associated with feelings of low self-esteem or poor body image. It is important to determine exactly what behaviors and social media engagements contribute to disordered relationships with food, assessing a user’s pre-existing weight/body concerns in relation to the amount and type of media they consume. Instagram in particular is included in this study, as it is an image-based social networking site where users can …

A Novel Three-Level Isolated Ac-Dc Pfc Power Converter Topology With Reduced Number Of Switches, Obaid Aldosari

Graduate Theses and Dissertations

The three-level isolated AC-DC power factor corrected (PFC) converter provides safe and more efficient power conversion. In comparison with two-level, three-level PFC converter has the advantages of low total harmonic distortion, low device voltage rating, low di/dt, better output performance, high power factor, and low switching losses at higher switching frequencies. The high frequency transformer (HFT) grants galvanic isolation, steps up or down secondary voltage, and limits damage in case of a fault current.

The existing three-level converter based on solid-state transformer (SST) topologies convert ac power from the electrical grid to a dc load while maintaining at least the …

Evolutionary Inference From Admixed Genomes: Implications Of Hybridization For Biodiversity Dynamics And Conservation, Tyler Chafin

Graduate Theses and Dissertations

Hybridization as a macroevolutionary mechanism has been historically underappreciated among vertebrate biologists. Yet, the advent and subsequent proliferation of next-generation sequencing methods has increasingly shown hybridization to be a pervasive agent influencing evolution in many branches of the Tree of Life (to include ancestral hominids). Despite this, the dynamics of hybridization with regards to speciation and extinction remain poorly understood. To this end, I here examine the role of hybridization in the context of historical divergence and contemporary decline of several threatened and endangered North American taxa, with the goal to illuminate implications of hybridization for promoting—or impeding—population persistence in …

Low Latency Anomaly Detection With Imperfect Models, Samrat Nath

Graduate Theses and Dissertations

The problem of anomaly detection deals with detecting abrupt changes/anomalies in the distribution of sequentially observed data in a stochastic system. This problem applies to many applications, such as signal processing, intrusion detection, quality control, medical diagnosis, etc. A low latency anomaly detection algorithm, which is based on the framework of quickest change detection (QCD), aims at minimizing the detection delay of anomalies in the sequentially observed data while ensuring satisfactory detection accuracy. Moreover, in many practical applications, complete knowledge of the post-change distribution model might not be available due to the unexpected nature of the change. Hence, the objective …

Practitioner Use Of And Attitudes Toward Video-Conferencing For The Delivery Of Evidence-Based Telemental Health Interventions, Kathryn Parisi

Graduate Theses and Dissertations

Compared to telehealth delivery of interventions for physical health issues, the implementation of evidence-based psychosocial interventions using technology has less support. Video-conference delivery (VCD) has the potential to increase accessibility to effective treatments, although its use remains limited and understudied. This study employed a mixed methods approach in surveying mental health practitioners about their attitudes regarding the use of video-conference methods to deliver evidence-based interventions. One hundred and eleven practitioners were sampled from several national and regional practice organizations and administered quantitative surveys about their use of and attitudes towards VCD of evidence-based interventions. The relationship between clinician-level technology access, …

Effects Of Light, Nutrients, And Salts On Microbial Biofilm Productivity And Detrital Processing In Aquatic Mesocosms, Bethanie Brooke Howard-Parker

Graduate Theses and Dissertations

Anthropogenic activities associated with urbanization, agriculture, and resource extraction continue to increase to support increasing needs of the growing population. These activities increase the amounts of pollutants entering freshwater streams and put aquatic ecosystems at structural and functional risk. Aquatic microbes play an important role in detrital processing in streams as a key linkage in moving carbon from detrital stocks into aquatic food webs. My research investigates the effects of light, nutrients, and salts on detrital microbes and decomposition in freshwaters using a mesocosm approach. In chapter one, I modified a current priming effect (PE) hypothesis model to include light …

Evaluation Of Microbiome On Chicken Necrotic Enteritis And Growth Performance, Mussie Abraha

Graduate Theses and Dissertations

Necrotic enteritis (NE) has re-emerged following restriction of antimicrobial usage and costs $6 billion every year worldwide. The primary objective of the studies was to evaluate prevention and treatment of NE using a microbiota metabolic product, secondary bile acid deoxycholic acid (DCA), in drinking water. Day-old birds were tagged and placed in floor pens. In experiments 1 and 2, the birds were infected with Eimeria maxima (Em) at d 18 and C. perfringens at d 23 and 24 and the birds were euthanized at d 26. In experiment 3, birds were infected with Eimeria at d 20 and C. perfringens …

Understanding Ice Mixtures Under Pluto Simulated Conditions And Their Implications For Geophysical Processes, Caitlin Joannah Ahrens

Graduate Theses and Dissertations

New Horizons at Pluto has given the planetary science community the first images of Pluto’s surface, including geologic wonders and compositional variability. Methane, nitrogen, and carbon monoxide make up the bulk of the volatile plutonian surface along with water ice. In this work, these three main volatiles are specifically investigated in the laboratory setting to understand the spectral properties and behavior of binary and ternary mixtures. The spectra are taken in the near-infrared wavelengths (1 – 2.5 µm) using Fourier transform infrared (FTIR) spectroscopy techniques utilizing the Pluto Simulation Chamber housed at the University of Arkansas, which can reach conditions …

Data Breach Consequences And Responses: A Multi-Method Investigation Of Stakeholders, Hamid Reza Nikkhah

Graduate Theses and Dissertations

The role of information in today’s economy is essential as organizations that can effectively store and leverage information about their stakeholders can gain an advantage in their markets. The extensive digitization of business information can make organizations vulnerable to data breaches. A data breach is the unauthorized access to sensitive, protected, or confidential data resulting in the compromise of information security. Data breaches affect not only the breached organization but also various related stakeholders. After a data breach, stakeholders of the breached organizations show negative behaviors, which causes the breached organizations to face financial and non-financial costs. As such, the …

(In)Equality., Jongin Choi

Graduate Theses and Dissertations

(in)Equality. centers around my experiences as a transnational person and those around me who have affected my current concept of equality and cultural histories. My visual methodologies cover digital photography and editing, inkjet printing, and laser engraving: multimedia in a process of new discovery, translation between analog and digital, and rearticulation. The exhibition includes portraits peering down from above, illuminated by projected patterns and manipulated messages from Nike’s “Equality.” (2017). The purpose of this thesis paper is to describe the elements of identity, marginalization, and personal reaction to advertising, as well as the and theories which have shaped this project. …

Evaluation Of Concrete Deck Curing Regimens Using Capillary Pressure Sensing System, Samuel Spann

Graduate Theses and Dissertations

Early-age plastic shrinkage cracking is a common problem with the construction of concrete bridge decks due to the high surface area-to-volume ratio and exposure to potentially detrimental environmental effects. Curing regimens are utilized to mitigate cracking risk during the plastic stage of the concrete; the curing regimens evaluated for this study were wet burlap-polyethylene sheeting, two acrylic curing compounds, and one lithium compound. Capillary pressure in the water filled pores has been shown to correlate to the plastic shrinkage cracking risk of concrete. A new portable system has been developed to measure the capillary pressure that could potentially be used …

Truck Activity Pattern Classification Using Anonymous Mobile Sensor Data, Taslima Akter

Graduate Theses and Dissertations

To construct, operate, and maintain a transportation system that supports the efficient movement of freight, transportation agencies must understand economic drivers of freight flow. This is a challenge since freight movement data available to transportation agencies is typically void of commodity and industry information, factors that tie freight movements to underlying economic conditions. With recent advances in the resolution and availability of big data from Global Positioning Systems (GPS), it may be possible to fill this critical freight data gap. However, there is a need for methodological approaches to enable usage of this data for freight planning and operations.

To …

The Effects Of Seed-Applied Fluopyram On Root Penetration And Development Of Meloidogyne Incognita On Cotton And Soybean, Tracy Hawk

Graduate Theses and Dissertations

Plant-parasitic nematodes are major pests of cotton and soybean in Arkansas, and across the Southern United States. These nematodes cause more than $3 billion worth of crop losses each year, in part due to lack of available control tactics, such as nematicides. Fluopyram has recently been registered as a seed-treatment nematicide in agronomic crops. The toxicity of fluopyram against Meloidogyne incognita infection has been reported, however, information on root protection provided by fluopyram against Meloidogyne incognita is lacking. The first objective of this research was to evaluate the effect seed-applied fluopyram had on nematode development, root galling, and reproduction on …

Use Of Aerial Imagery And Novel Experimental Design To Determine The Distribution Of Foliar Diseases On Soybean And Improve Efficiency Of Product Testing, Mckayla Patterson

Graduate Theses and Dissertations

Soybeans are grown on approximately 1.3 million ha in Arkansas generating an estimated $1.7 billion annually. Foliar diseases on soybean can result in economic losses. Growers spend significant time and money on disease scouting via crop consultants and often (subsequent) fungicide applications. Fungicide trials are often arranged in small plots designs. In these scenarios, spatial variability of foliar disease is minimized. While it is advantageous to minimize variance outside of treatment differences, another limitation with many small plot trials is ample disease pressure or having only lower severity. Within a commercial production field, soil types and disease severities vary. Logically, …

Understanding How The Effectors Hopd1 And Hopg1 From The Bacterial Pathogen Pseudomonas Syringae Pv. Tomato Dc3000 Target The Arabidopsis Thaliana Protein Atnhr2b To Cause Disease In Plants, Catalina Maria Rodriguez Puerto

Graduate Theses and Dissertations

The pathogenicity of Pseudomonas syringae is associated with the type III secretion system (T3SS), a complex of proteins assembled in the inner and outer bacterial membranes that traverses the plant cell wall to deliver bacterial proteins into the cytoplasm of plant cells. The effector proteins translocated into the plant cells are called Hops (Hypersensitive response and pathogenicity outer proteins). Bacterial effectors target plant immune proteins to suppress defense responses and enhance bacterial parasitism. The Arabidopsis thaliana nonhost resistance 2B (AtNHR2B), a recently identified immune protein, is degraded after inoculation with the adapted pathogen of Arabidopsis, P. syringae pv tomato DC3000 …

The Physicochemical Properties Of Soy Protein Hydrolysate And Its Formulation And Stability With Encapsulated Probiotic, John Stricklin Edwards

Graduate Theses and Dissertations

Soy protein isolate (SPI) and probiotics can serve as a functional ingredient and beneficial supplement, respectively, to food formulations, but few studies focus on the compatibility of these two ingredients. The objective of this study was to prepare soy protein isolate (SPI) from defatted soybean flour and identify an optimal hydrolysis protocol to create soy protein hydrolysates (SPH) with improved solubility and functional properties and achieve an optimum encapsulation technique for probiotics and to determine the in vitro viability of encapsulated probiotic cells with SPH in a gastrointestinal environment. The SPI was prepared using an alkaline extraction procedure for solubility …

Components Of Mindfulness Training: Impacts On Attention And Affect, Maximilian Fey

Graduate Theses and Dissertations

The literature on mindfulness supports a distinction between two components of non-judgmental acceptance and directed attention. The present research analyzed whether there are distinct differences in attentional capabilities or affect between mindfulness inductions which differed in either including only directed attention or directed attention and non-judgmental acceptance. I hypothesized that the acceptance component of mindfulness would increase participants sustained attentional capabilities relative to a control condition; furthermore, I hypothesized that the non-judgmental acceptance component of mindfulness would lead to significant increases in positive affect and decreases in negative affect relative to control. Lastly, I hypothesized that an individual difference measure …

Asymmetric Synthesis Of The C29-C34 Moiety Of Fragment A Of The Antascomicin B & Thermal Azole Based Claisen Rearrangements, Dharma Theja Nannapaneni

Graduate Theses and Dissertations

The dissertation describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B and Thermal azole based Claisen rearrangements. In chapter 1, we describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B. The non-immunosuppressant Rapamycin, Ascomycin, and Tacrolimus (FK506), strongly binds with FKBP12, the ligand FKBP12 complexes responsible for immunosuppressive activity. Antascomicin B structurally related to Rapamycin, Ascomycin, and Tacrolimus (FK506), binds strongly to FKBP12, yet does not shown immunosuppressive activity. The ligand FKBP12 binding complexes shown to have potent neuroprotective and neurogenerative properties in mouse models of Parkinson’s disease. The linear synthesis of …

Use Of Harvest Weed Seed Control Strategies In Arkansas Soybean, Jeremy Kyle Green

Graduate Theses and Dissertations

Today, most growers use chemical weed management programs; however, a sole reliance on herbicides will place more resistance selection pressure on the weeds to which the herbicide is being applied. As herbicide resistance continues to grow and rob growers of yield, alternative weed control options are being sought to create complex integrated weed management programs to prolong the use of effective herbicides. Harvest weed seed control (HWSC) is a non-chemical practice that has been widely adopted in Australia due to herbicide resistance problems. In most cases, herbicide-resistant weeds that survive applications of herbicides produce viable seed that pass through the …

The Rise Of Anti-Immigration Populist Radical Right Parties: The Effect Of The Syrian Conflict On Refugee Resettlement And Migration Policies In Germany And Austria, Sara Kouchehbagh

Graduate Theses and Dissertations

The effects of Syrian migration in Europe have revolutionized refugee resettlement globally. Most immigration and refugee problems have historically been settled similarly post WWII, however, Syria is the largest refugee crisis since WWII. It is important to learn how to respond to future conflicts with displacement and resettlement affecting Western countries that are unprepared to respond to a conflict of such magnitude. This thesis will compare previous conflicts and the Syrian conflict, while highlighting the resilient political momentum of reactionary new political groups in European states, particularly Germany and Austria.

The research and results from this study will include data …

Retaining Special Education Teachers In A Rural Arkansas School District, Eric Ryan Gotte

Graduate Theses and Dissertations

According to published research, rural school districts across the United States are challenged with obstacles in recruiting and retaining special education teachers. This study presents findings based on special education teachers’ experiences teaching within one rural Arkansas school district. This instrumental single case study investigates the factors that encourage special education teachers to remain in their current position within a rural Arkansas school district. Qualitative data is analyzed from 11 participants, 9 current special educators, 1 special education director, and 1 retired special education teacher. All of the participants are from one rural Arkansas school district in order to gain …

Development Of A Text Message Stress Management Intervention And Its Impact On Perceived Stress And Coping Self-Efficacy Among Student Nurses, Kristin Jaye Henderson

Graduate Theses and Dissertations

Purpose: The purpose of the two studies was to develop a text message intervention and examine its effects on lowering perceived stress and increasing coping self-efficacy among nursing students. We also explored stress perceptions and investigated student satisfaction with the text message stress management program. Methods: For the first study, twenty three students participated in the focus groups for intervention development. Sample messages were presented to participants and feedback was requested. The messages were modified based on student feedback. The second study utilized an experimental pre/post design with a convenience sample (N=101) to examine the effects of the text message …

Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal

Graduate Theses and Dissertations

Anthropogenic disturbance, in its multiple facets represents a major threat to biodiversity and habitat quality. Consequently, extensive research is guided towards understanding anthropogenic disturbance and their effects on wildlife for development of wildlife management plans. However, for development of effective wildlife management plans it is imperative that we understand the habitat use and preference by local fauna along with effects of anthropogenic presence. In this dissertation, I studied the habitat usage and preferences of Shrubland birds in the Eastern Ghats of India during the pre-monsoon and post monsoon seasons. Eastern Ghats show a marked difference from pre-monsoon season to post-monsoon …

High Frequency Ltcc Based Planar Transformer, Adithya Venkatanarayanan

Graduate Theses and Dissertations

As we move towards high power and higher frequency related technology, conventional wire-wound magnetics have their own limitations which has led path to the development of planar based magnetic materials. Nowadays more planar magnetic technology has been employed because it is easier to fabricate them. The planar magnetic is a transformer or an inductor that replaces the wire-wound transformer or inductors which generally uses copper wires. One of the main reasons why we move to planar magnetic technology is its operation at higher frequency which provides higher power density. This study explains in detail about the design and fabrication of …

The Cognition Of Controversy: Examining Policy Elites’ Narrative Cognition And Communication Around Hydraulic Fracturing Practices In The U.S., Rachael M. Moyer

Graduate Theses and Dissertations

The use of hydraulic fracturing (HF) technologies to extract oil and gas in the United States has sparked contentious policy debates, producing inconsistent and inefficient policies that have done little to address the impacts of HF in any comprehensive way. Debates are accompanied by competing policy narratives that position HF as either an environmental threat or an economic opportunity, but little is known about how policy narratives around HF are used by individuals. This dissertation systematically examines how individuals cognitively internalize elements of competing HF policy narratives. Organized into three empirical chapters, this dissertation analyzes narrative cognition (Jones, Shanahan, and …

Curing Consumption: Blood Drinkers Of The Nineteenth Century, Rachel Erin Catlett Widmer

Graduate Theses and Dissertations

During the nineteenth century burgeoning cities in the United States saw the spread of disease. Most common among all parts of society was tuberculosis or as it was commonly known at the time, consumption. The most terrifying aspect of consumption was that it could attack anyone at any time and no cure existed. The poetic image of a red stained handkerchief was a death sentence. The common cure was to seek fresh air in a warmer climate. However, for some Americans an experimental cure seemed hopeful and easily accessible, drinking blood. According to many newspaper accounts consumptive victims were not …