Digital Commons Network^™

Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys

Graduate Theses and Dissertations

A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …

Effects Of Critical Reflection On University Students’ Cognitive Achievement In Agricultural Mechanization, Patterson P. Hilaire

Graduate Theses and Dissertations

Experiential learning continues to play a vital role in agricultural education and mechanization laboratories (Shoulders & Myers, 2013). An essential component of experiential learning is critical reflection. Critical reflection helps students process and construct meaning from laboratory experiences. A study conducted by Shoulders and Myers (2013) revealed that only 15.4% of the agricultural educators the researchers interviewed incorporated reflective practices laboratory experiences. The purpose of this study was to evaluate the effect of critical reflection on students’ achievement following five agricultural mechanization laboratory activities. The results from this study revealed that critical reflection had a consistently positive effect on immediate …

Shifting Abortion Attitudes Using An Empathy-Based Media Intervention: A Randomized Controlled Study, Mary Ellen Hunt

Graduate Theses and Dissertations

U.S. abortion restrictions diminish access and perpetuate a culture of hostility toward abortion seekers. Support for restrictions is high—potentially, because restriction knowledge is low and attitudes are complex. The current study focused on knowledge and support of restrictions and empathy for abortions seekers among Arkansans. The purpose was to evaluate the effectiveness of a video intervention intended to increase awareness of Arkansas abortion restrictions and induce empathy for abortion seekers.

Using a randomized controlled trial with pre-, post-, and follow-up design, a sample of Arkansans (N = 369) were randomly assigned to one of five video conditions--either a control or …

A Phenomenological Study Of The Lived Experiences Of Counseling Students In A Co-Facilitated Experiential Group, Alexandra Meyers

Graduate Theses and Dissertations

Research in the fields of experiential learning, group psychotherapy, and neuroscience has supported the inclusion of the experiential group in counseling training programs due to the potential for positive impact on students’ personal and professional development (Badenoch & Cox, 2010; Denninger, 2010). Investigations exploring counseling students’ experiences of the experiential group have been primarily limited to quantitative studies, while in-depth qualitative inquiry has been minimal. Additionally, an extensive review of the literature has found there have been no qualitative studies examining experiential groups co-facilitated by a course instructor and a doctoral student. The purpose of this phenomenological study was to …

Fertility Awareness Based Methods (Fabms): Evaluating And Promoting Female Interest For Purposes Of Health Monitoring And Family Planning, Amylynn Smith

Graduate Theses and Dissertations

Natural or fertility awareness-based methods (FABMs) help users monitor, interpret, and systematically chart female biological markers. FABMs are used as family planning methods and sometimes as reproductive health monitoring methods. The American College of Obstetricians and Gynecologists (ACOG) encourages medical professionals to use female reproductive cycle patterns, ‘the female fifth-vital sign’, as a means of improving the diagnosis and treatment of reproductive health diseases, disorders, and conditions. Patients need to have accurate knowledge of healthy and unhealthy cycle patterns. The general public does not have a sufficient level of fertility health knowledge. This study examined whether females that are interested …

The Effect Of Osmotic Stimulation Of Copeptin On Glucose Metabolism In Healthy Adults, Lisa Tjorven Jansen

Graduate Theses and Dissertations

Diabetes is currently affecting 30 million Americans. To combat disease onset, lifestyle interventions have been focused on. Low water intake, alongside elevated concentrations of circulating copeptin, has been linked to increased risk for. However, it is unknown whether this effect on glucose regulation is acute or chronic. Furthermore, no study to date assessed the effects of copeptin independent of the renin-angiotensin-aldosterone system (RAAS). Purpose: The purpose of these studies was therefore two-fold: 1) to establish high endogenous copeptin concentrations independent of RAAS, and 2) to assess glucose metabolism following a standardized oral glucose tolerance test (OGTT) during high concentrations of …

Optimization Of The Light Environment For Broiler Chickens, Douglas J. Aldridge

Graduate Theses and Dissertations

The use of artificial light sources has been necessitated by the use of fully enclosed rearing facilities for improved environmental control. Light Emitting Diodes (LED) have been developed as a light source that reduce the utilities required to provide equal light to that of incandescent sources. The following reports were carried out to investigate the effects of two light color temperatures, light intensity and light intensity gradients on broiler chicken production and behavior. The first investigation consisting of two consecutive trials investigated the effect of two light color temperatures (2700 K and 5000 K) in addition to the preference for …

Teacher Diversity Issues Among Hispanics And English Language Learners (Ells): Perspectives Of Administrators And Teachers In A Mid-South Town, Samantha Juncia Julien

Graduate Theses and Dissertations

Although the English Language Learner (ELL) student population is steadily increasing, the American teaching workforce remains mainly white and monolingual. This sector has yet to reflect the change in ELLs and teachers of color, who will be able to adequately provide culturally responsive instruction to these students. There is an urgent need to recruit and train teachers in culturally responsive pedagogy with the purpose of providing educational, cultural and social supports for the growing ELL population in the country (Farahnaz, 2012). Because of this, the American educational system is revamping some of its earlier pedagogical approaches, including the introduction of …

Synchrophasor-Based Fault Location Detection And Classification, In Power Systems, Using Artificial Intelligence, Hemal Falak

Graduate Theses and Dissertations

With the introduction of sophisticated electronic gadgets which cannot sustain interruption in the provision of electricity, the need to supply uninterrupted and reliable power supply, to the consumers, has become a crucial factor in the present-day world. Therefore, it is customary to correctly identify fault locations in an electrical power network, in order to rectify faults and restore power supply in the minimum possible time. Many automated fault location detection algorithms have been proposed, however, prior art requires topological and physical information of the electrical power network. This thesis presents a new method of detecting fault locations, in transmission as …

Daily To Seasonal Moisture Signals Present In Sub-Annual Tree-Ring Data, Ian Howard

Graduate Theses and Dissertations

In recent decades, there has been an increase in the development of sub-annual earlywood (EW) and latewood (LW) width tree-ring chronologies that have been used to make long-term inferences about discrete seasonal moisture variability for different regions of North America. This doctoral research developed a new network of EW, LW, and adjusted latewood (LWa) tree-ring chronologies from the western Great Plains. These chronologies were used to reconstruct 300+ years of spring and summer moisture variability over the northern and southern Plains. The reconstructions document new information about the long-term seasonal climate history of the Great Plains, including the unusual nature …

Hardware Ip Classification Through Weighted Characteristics, Brendan Mcgeehan

Graduate Theses and Dissertations

Today’s business model for hardware designs frequently incorporates third-party Intellectual Property (IP) due to the many benefits it can bring to a company. For instance, outsourcing certain components of an overall design can reduce time-to-market by allowing each party to specialize and perfect a specific part of the overall design. However, allowing third-party involvement also increases the possibility of malicious attacks, such as hardware Trojan insertion. Trojan insertion is a particularly dangerous security threat because testing the functionality of an IP can often leave the Trojan undetected. Therefore, this thesis work provides an improvement on a Trojan detection method known …

Asynchronous Circuit Synthesis Using Multi-Threshold Null Convention Logic, Nicholas Renoudet Mize

Graduate Theses and Dissertations

As the demand for an energy-efficient alternative to traditional synchronous circuit design grows, hardware designers must reconsider the traditional clock tree. By doing away with the constrains of a clock, asynchronous sequential circuit designs can achieve a much greater level of efficiency. The utilization of asynchronous logic synthesis flows has enabled researchers to better implement asynchronous circuit designs which have been optimized using the same industry standard tools that are already used in sequential synchronous designs. This thesis offers a new flow for such tools which implements the MTNCL asynchronous circuit architecture.

Towards A Prototype Platform For Ros Integrations On A Ground Robot, Taylor Joseph Linville Whitaker

Graduate Theses and Dissertations

The intent of this work was to develop, evaluate, and demonstrate a prototype robot platform on which ROS integrations could be explored. With observations of features and requirements of existing industrial and service mobile ground robots, a platform was designed and outfitted with appropriate components to enable the most common operational-critical functionalities and account for unforeseen components and features. The resulting Arlo Demonstration Robot accommodates basic mapping, localization, and navigation in both two and three-dimensional space as well as additional safety and teleoperation features. The control system is centered around the Zybo Z7 FPGA SoC hosting a custom hardware design. …

H2 Control For Improved Stability Of Multi-Area Electric Power System With High Levels Of Inverter-Based Generation, Muthanna Abdulkareem Al-Sarray

Graduate Theses and Dissertations

Increased generation capacity from non-dispatchable energy resources such as wind and solar has created challenges to ensuring the reliable delivery of electric power. This research develops a systematic three-step method of assessing the reliability of electric power systems under a variety of different possible fault conditions to ensure that overall system stability is preserved in a manner the meets regulatory requirements. The first step is a risk-based reliability method (RBRM) that accounts for the probability of a line outage versus the severity of impact. This allows system planners to judiciously allocate expenses for reliability improvements based on the greatest economic …

A Silicon Germanium Cmos Linear Voltage Regulator For Wireless Agricultural Applications, Aminta Naidili Castillo Robles

Graduate Theses and Dissertations

This thesis presents the design, simulation and test results of a silicon germanium (SiGe) complementary metal-oxide-semiconductor (CMOS) linear regulator. The objective of the circuit is to power other analog devices regardless of the load current and input voltage changes. The application of this regulator is to be part of a project developing a miniaturized semiconductor platform that can be inserted into stems of crops in order to measure data inside the plant and then send it wirelessly to the user. The linear regulator was designed on a BiCMOS SiGe 0.13µm which is a GlobalFoundries process. It has been tested at …

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Graduate Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive …

Characterization Of Hydride Vapor Phase Epitaxy Grown Gan Substrates For Future Iii-Nitride Growth, Alaa Ahmad Kawagy

Graduate Theses and Dissertations

The aim of this research is to investigate and characterize the quality of commercially obtained gallium nitride (GaN) on sapphire substrates that have been grown using hydride vapor phase epitaxy (HVPE). GaN substrates are the best choice for optoelectronic applications because of their physical and electrical properties. Even though HVPE GaN substrates are available at low-cost and create the opportunities for growth and production, these substrates suffer from large macro-scale defects on the surface of the substrate.

In this research, four GaN on sapphire substrates were investigated in order to characterize the surface defects and, subsequently, understand their influence on …

Privileged Eyes: How A Look In The Mirror Informed The Creation Of Marilyn And Desiree, Halley Electra Mayo

Graduate Theses and Dissertations

This thesis is for the performance of Desiree in A Little Night Music, by Stephen Sondheim and Hugh Wheeler; the development, writing, and performance of the one-person-show Privileged Eyes; and development of a website and statement of artistry.

Differences In Kaplan Integrated Exam Scores Based On Institutional Factors, Lee Ann Danner

Graduate Theses and Dissertations

Registered Nurses constitute the largest health care occupation in the United States. Current entry-level education for the profession of nursing is either an Associate Degree in Nursing (ADN) or Bachelor of Science in Nursing (BSN) (Altman, 2011). After successful completion of a nursing program, all nursing graduates must apply to take the National Council Licensure Examination (NCLEX-RN). The pass rate for first time United States educated NCLEX-RN exam test takers in 2017 was 87.11% leaving 12.89% unsuccessful (NCSBN, 2018). A nursing programs quality and recruitment are often influenced by a students’ ability to pass the NCLEX-RN on the first attempt. …

Electrophysiological Correlates Of Visual Object Category Formation In A Prototype-Distortion Task, Stephanie Marie Long

Graduate Theses and Dissertations

In perceptual learning studies, participants engage in extensive training in the discrimination of visual stimuli in order to modulate perceptual performance. Much of the literature in perceptual learning has looked at the induction of the reorganization of low-level representations in V1. However, much remains to be understood about the mechanisms behind how the adult brain (an expert in visual object categorization) extracts high-level visual objects from the environment and categorically represents them in the cortical visual hierarchy. Here, I used event-related potentials (ERPs) to investigate the neural mechanisms involved in object representation formation during a hybrid visual search and prototype …

Seeking Success: A Case Study Of African American Male Retention At A Two-Year College, Richard Latroy Moss

Graduate Theses and Dissertations

There is a problem in higher education in the United States. African American students, specifically males, are not being retained and graduating. This problem is even more evident for students that attend two year colleges. African American male students lag behind white males, Hispanic males and African American females, in retention and graduation rates. This problem has caught the attention of many leaders. Policy makers and college leaders are among those who seek to understand the why and find solutions to the challenge of African American male student retention at two year colleges, as two year colleges are becoming the …

Molecular Basis Of Pathogenesis And Host Determination In Cercospora Sojina: From Phenotypic To Genotypic Patterns, Wagner Calegari Fagundes

Graduate Theses and Dissertations

Frogeye leaf spot (FLS), caused by Cercospora sojina, is an important and recurrent disease of soybean in many production regions. Genetic resistance is potentially one of the most cost-effective and sustainable strategies to control FLS. However, C. sojina has already demonstrated the ability to overcome resistance conveyed by single R-genes (resistance genes) of soybeans, followed by the emergence of new physiological races. Although understanding population genomics and the virulence gene inventories in fungal plant pathogens is extremely important to improve disease control measures, studies regarding host specificity and pathogenesis in C. sojina are very limited. Therefore, the overarching goal of …

Understanding And Predicting Nematode Damage On Soybean Using Spatially Weighted Analysis, Barry Boney

Graduate Theses and Dissertations

Aerial imagery offers great potential as a predictive scouting method and could allow growers to better understand crop performance over time. Evidence suggests that the seed treatments fluopyram and abamectin result in decreased reproduction and root galling by Meloidogyne incognita, but yield protection in fields with higher or different nematode pressure is unclear. The objective of this work was to determine the efficacy of these seed treatments compared to 1,3-dichloropropene (1,3-D) applied site-specifically and then predict where these might best be applied to other fields. In a soybean field infested with M. incognita, apparent electrical conductivity was highly correlated with …

The Effect Of Incorporating End-User Customization Into Additive Manufacturing Designs, Jonathan D. Ashley

Graduate Theses and Dissertations

In the realm of additive manufacturing there is an increasing trend among makers to create designs that allow for end-users to alter them prior to printing an artifact. Online design repositories have tools that facilitate the creation of such artifacts. There are currently no rules for how to create a good customizable design or a way to measure the degree of customization within a design. This work defines three types of customizations found in additive manufacturing and presents three metrics to measure the degree of customization within designs based on the three types of customization. The goal of this work …

Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut

Graduate Theses and Dissertations

The underlying physics of failure are critical in assessing the long term reliability of power packages in their intended field applications, yet traditional reliability determination methods are largely inadequate when considering thermomechanical failures. With current reliability determination methods, long test durations, high costs, and a conglomerate of concurrent reliability degrading threat factors make effective understanding of device reliability difficult and expensive. In this work, an alternative reliability testing apparatus and associated protocol was developed to address these concerns; targeting rapid testing times with minimal cost while preserving fatigue life prediction accuracy. Two test stands were fabricated to evaluate device reliability …

Utilizing 3d Printed Analogue Soils To Investigate Specimen Size Effects In Triaxial Testing, Claire Louise Stewart

Graduate Theses and Dissertations

Triaxial testing is one of the fundamental laboratory tests used in geotechnical engineering to determine strength parameters, such as shear strength and friction angle. Investigating the minimum representative elementary volume (REV) can verify the independence of size effects on strength parameters and ensure that the scaled laboratory tests results are consistent, repeatable, and representative of field conditions. Although, REV has been studied for many applications, there is disagreement within geotechnical engineering of a minimum particle diameter to specimen diameter to minimize the size effects related to the REV in consolidated drained (CD) triaxial tests. This research study compared the strength …

Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz

Graduate Theses and Dissertations

Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and Pilot Plant filters operated at empty-bed contact times (EBCTs) of 4, 8, and 16 minutes were used to evaluate the performance of nutrient-amended (free ammonia and phosphorus) biofiltration for THM and DCAN precursor removal, as measured using formation potential (FP) tests. NOM surrogates – which include dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA254) and fluorescence-PARAFAC components – were measured weekly throughout the …

Philosophia Soteria: How Occupational Safety And Health Professionals Influence Decision Makers, Daniel Jay Snyder

Graduate Theses and Dissertations

The purpose of this study was to identify ideas about how occupational safety and health (OSH) professionals influence decision-makers on matters impacting occupational health and safety management systems. A modified nominal group technique was used that involved 67 participants in ten nominal groups and identified the most important ideas about how OSH professionals can influence workplace safety and health decision making. The research produced themes of communication, scientific, professionalism, leadership, adaptability, and business acumen that resulted in six domains of occupational safety and health professional influence.

The Role Of Dialect Words In Children’S Social Decisions, Madison Rose Myers-Burg

Graduate Theses and Dissertations

Recent research suggests that young children are capable of distinguishing between phonetically dissimilar spoken accents, yet have difficulty distinguishing between phonetically similar accents (Wagner, Clopper, & Pate, 2013). The present study aimed to determine whether the presence of dialect-specific vocabulary enhances young children’s ability to categorize speakers. Participants completed four training trials in which they were familiarized with photos of two children: one of whom used American English labels for test objects and one of whom used British English labels. After training trials, participants completed eight test trials in which they were asked to infer which target child would use …

The Role Of Information Communication Technologies (Icts) In Shaping Identity Threats And Responses, Mary Macharia

Graduate Theses and Dissertations

With the rising use of social media, people are increasingly experiencing, and responding to, identity threats online. This sometimes leads to online backlash via “cybermobs” or the creation of online social movements that traverse offline. Prior information systems (IS) research on identity threats and responses largely focuses on information communication technology (ICT) implementations within organizations in an offline context. Therefore, we lack understanding of ICT-mediated identity threats and responses and ways to promote healthier and productive interactions online. This two-essay dissertation seeks to fill this gap. Essay 1 combines a review of ICT-mediated identity threats with a qualitative study (based …