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Academic Stress in Student-Athletes

Description: Academic stress and the causes of such stress are subjects that are found in very few studies concerning student-athletes. Therefore, the purpose of this quantitative study is to determine how the following variables relate to academic stress and perceived stress either through correlations or differences--demographics, academic classification, major or field of study, athletic scholarship status, and season of sport (in- season/ out of season). An online questionnaire containing a Perceived Stress Scale and a Perception of Academic Stress scale were distributed to 151 student-athlete participants at a university in the southwest United States. The results indicated that biological sex has a significant relationship to perceived stress. No other variables were found significant to perceived stress or academic stress.
Date: May 2017
Creator: James, Christina

Adrenergic and Cholinergic Regulation of Cardiovascular Function in Embryonic Neotropic Cormorants (Phalacrocorax basilianus)

Description: Investigations of cholinergic and adrenergic tone on heart rate (fH) and mean arterial pressure (Pm) during embryonic development have been conducted on numerous avian species. While these investigations have documented that adrenergic tone, a continuous stimulation, on fH and Pm is vital to embryonic development in the birds studied to date, development of cholinergic tone on fH has been shown to vary even within species. Further, past studies have been bias to focus primarily on precocial species while altricial species remain poorly understood in this context. The goal of this investigation was to investigate the role of cholinergic and adrenergic tone on fH and Pm of an altricial species, the neotropic cormorant (P. brasilianus) to address this bias. The embryonic neotropic cormorant possesses B-and-a adrenergic tone on fH and Pm at 70% and 90% incubation while cholinergic tone on fH occurs at 90% incubation. This pattern of control is similar to that previously reported for several species of precocial birds suggesting the development of tonic cardiovascular regulation may be conserved across avian taxa.
Date: May 2017
Creator: Cummins, James B

Application of High Entropy Alloys in Stent Implants

Description: High entropy alloys (HEAs) are alloys with five or more principal elements. Due to these distinct concept of alloying, the HEA exhibits unique and superior properties. The outstanding properties of HEA includes higher strength/hardness, superior wear resistance, high temperature stability, higher fatigue life, good corrosion and oxidation resistance. Such characteristics of HEA has been significant interest leading to researches on these emerging field. Even though many works are done to understand the characteristic of these HEAs, very few works are made on how the HEAs can be applied for commercial uses. This work discusses the application of High entropy alloys in biomedical applications. The coronary heart disease, the leading cause of death in the United States kills more than 350,000 persons/year and it costs $108.9 billion for the nation each year in spite of significant advancements in medical care and public awareness. A cardiovascular disease affects heart or blood vessels (arteries, veins and capillaries) or both by blocking the blood flow. As a surgical interventions, stent implants are deployed to cure or ameliorate the disease. However, the high failure rate of stents has lead researchers to give special attention towards analyzing stent structure, materials and characteristics. Many works related to alternate material and/or design are carried out in recent time. This paper discusses the feasibility of CoCrFeNiMn and Al0.1CoCrFeNi HEAs in stent implant application. This work is based on the speculation that CoCrFeNiMn and Al0.1CoCrFeNi HEAs are biocompatible material. These HEAs are characterized to determine the microstructure and mechanical properties. Computational modeling and analysis were carried out on stent implant by applying CoCrFeNiMn and Al0.1CoCrFeNi HEAs as material to understand the structural behavior.
Date: May 2017
Creator: Alagarsamy, Karthik

Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas

Description: Rainfall interception is one mechanism by which tree canopies can reduce surface runoff in urban areas. The objectives of this research were to: 1) quantify rainfall interception by urban tree canopies, and 2) determine the influence of vegetation and microenvironmental factors on rainfall interception rates. In the city of Denton, Texas, 30 mature post oak (Quercus stellata) and blackjack oak (Quercus marilandica) trees were selected for study. Trees were assigned to one of three categories: clusters of trees on greenspace (CG), isolated trees on greenspace (IG), and isolated trees surrounded by pavement (IP). Throughfall (the volume of water that travels through the canopy and reaches the soil surface) collectors were placed beneath these trees and rainfall collectors were placed in nearby open areas. Throughfall and rainfall were collected daily from 19 March to 4 July. Interception was calculated as the difference between throughfall and gross rainfall. Over the study period, there were 27 days with measurable rainfall; daily rainfall ranged from 1-51 mm. Over the sampling period, rainfall interception for individual trees ranged from -10% to 49%, indicating high spatial variability in interception. Percent interception was highest for the CG treatment (22.7 ± 3.8 SE), intermediate for IG (27.4 ± 2.3 SE), and lowest for IP (9.1 ± 4.9 SE). Factors like wind exposure, wind-driven rain and overall tree health may help explain this variability. This research will contribute to our knowledge of hydrological fluxes in urban areas and the role of urban green infrastructure in stormwater runoff mitigation.
Date: May 2017
Creator: Edington, Patrick

Automated GUI Tests Generation for Android Apps Using Q-learning

Description: Mobile applications are growing in popularity and pose new problems in the area of software testing. In particular, mobile applications heavily depend upon user interactions and a dynamically changing environment of system events. In this thesis, we focus on user-driven events and use Q-learning, a reinforcement machine learning algorithm, to generate tests for Android applications under test (AUT). We implement a framework that automates the generation of GUI test cases by using our Q-learning approach and compare it to a uniform random (UR) implementation. A novel feature of our approach is that we generate user-driven event sequences through the GUI, without the source code or the model of the AUT. Hence, considerable amount of cost and time are saved by avoiding the need for model generation for generating the tests. Our results show that the systematic path exploration used by Q-learning results in higher average code coverage in comparison to the uniform random approach.
Date: May 2017
Creator: Koppula, Sreedevi

Bodies of Evidence: A Qualitative Analysis of the Lived Experiences of Female Central American and Mexican Asylum Seekers in Dallas

Description: This work addresses the experiences of female asylum seekers from Central and Mexico currently living in Dallas, TX. The main purpose is to analyze how these women engage in the gendered processes of both migrating to and accessing legal resources and protection within the United States. As the women move through male-dominated spaces in their home country, the borderlands, and the asylum court they must challenge the patriarchal institutions that attempt to silence their narratives and criminalize their bodies. Their physical wounds become evidence in the courtroom, while outside of the courtroom their movements are monitored and tracked through multiple mechanisms of state control: ankle monitors, detention centers, ICE check-ins. They face intersectional discrimination as they are targeted as both women and immigrants. However, these female asylum seekers are not victims. They constantly display agency as they represent themselves in court, find solace in their faith, and form community with each other.
Date: May 2017
Creator: Kober, Ryan Kylie

Brain Computer Interface (BCI) Applications: Privacy Threats and Countermeasures

Description: In recent years, brain computer interfaces (BCIs) have gained popularity in non-medical domains such as the gaming, entertainment, personal health, and marketing industries. A growing number of companies offer various inexpensive consumer grade BCIs and some of these companies have recently introduced the concept of BCI "App stores" in order to facilitate the expansion of BCI applications and provide software development kits (SDKs) for other developers to create new applications for their devices. The BCI applications access to users' unique brainwave signals, which consequently allows them to make inferences about users' thoughts and mental processes. Since there are no specific standards that govern the development of BCI applications, its users are at the risk of privacy breaches. In this work, we perform first comprehensive analysis of BCI App stores including software development kits (SDKs), application programming interfaces (APIs), and BCI applications w.r.t privacy issues. The goal is to understand the way brainwave signals are handled by BCI applications and what threats to the privacy of users exist. Our findings show that most applications have unrestricted access to users' brainwave signals and can easily extract private information about their users without them even noticing. We discuss potential privacy threats posed by current practices used in BCI App stores and then describe some countermeasures that could be used to mitigate the privacy threats. Also, develop a prototype which gives the BCI app users a choice to restrict their brain signal dynamically.
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Date: May 2017
Creator: Bhalotiya, Anuj Arun

Cardiovascular Response to a Behavioral Restraint Challenge: Urge Magnitude Influence in Men and Women

Description: Agtarap, Wright, Mlynski, Hammad, and Blackledge took an initial step in providing support for the predictive validity of a new conceptual analysis concerned with behavioral restraint, defined as active resistance against a behavioral impulse or urge. The current study was designed to partially replicate and extend findings from their study, employing a common film protocol and a procedure for inducing low- and high levels of fatigue. Analyses on key data indicated that the fatigue manipulation was ineffective. On the other hand, they supported the suggestion that behavioral restraint should be proportional to the strength of an urge being resisted so long as success is perceived as possible and worthwhile. Analyses also provided evidence of gender differences for this behavioral restraint task. Women showed relatively enhanced CV responses to my manipulation of urge magnitude, performed less well, rated the behavioral restraint challenge as harder, and rated success on the more difficult behavioral restraint task as more important. A broad indication is that men and women can differ in the strength of impulses they experience in response to stimulus presentations as well as in the importance they place on resisting the impulses.
Date: May 2017
Creator: Mlynski, Christopher

Case Studies to Learn Human Mapping Strategies in a Variety of Coarse-Grained Reconfigurable Architectures

Description: Computer hardware and algorithm design have seen significant progress over the years. It is also seen that there are several domains in which humans are more efficient than computers. For example in image recognition, image tagging, natural language understanding and processing, humans often find complicated algorithms quite easy to grasp. This thesis presents the different case studies to learn human mapping strategy to solve the mapping problem in the area of coarse-grained reconfigurable architectures (CGRAs). To achieve optimum level performance and consume less energy in CGRAs, place and route problem has always been a major concern. Making use of human characteristics can be helpful in problems as such, through pattern recognition and experience. Therefore to conduct the case studies a computer mapping game called UNTANGLED was analyzed as a medium to convey insights of human mapping strategies in a variety of architectures. The purpose of this research was to learn from humans so that we can come up with better algorithms to outperform the existing algorithms. We observed how human strategies vary as we present them with different architectures, different architectures with constraints, different visualization as well as how the quality of solution changes with experience. In this work all the case studies obtained from exploiting human strategies provide useful feedback that can improve upon existing algorithms. These insights can be adapted to find the best architectural solution for a particular domain and for future research directions for mapping onto mesh-and- stripe based CGRAs.
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Date: May 2017
Creator: Malla, Tika Kumari

Catalytic Properties and Mechanical Behavior of Metallic Glass Powders

Description: Lack of crystalline order and microstructural features such as grain/grain-boundary in metallic glasses results in a suite of remarkable attributes including very high strength, close to theoretical elasticity, high corrosion and wear resistance, and soft magnetic properties. By altering the morphology and tuning of composition, MGs may be transformed into high-performance catalytic materials. In this study, the catalytic properties of metallic glass powders were demonstrated in dissociating toxic organic chemicals such as AZO dye. BMG powders showed superior performance compared to state of the art crystalline iron because of their high catalytic activity, durability, and reusability. To enhance the catalytic properties, high energy mechanical milling was performed to increase the surface area and defect density. Iron-based bulk metallic glass (BMG) of composition Fe48Cr15Mo14Y2C15B6 was used because of its low cost and ability to make large surface area by high energy ball milling. AZO dye was degraded in less than 20 minutes for the 9 hours milled Fe-BMG. However, subsequent increase in ball milling time resulted in devitrification and loss of catalytic activity as measured using UV-Visible spectroscopy. Aluminum-based bulk metallic glass (Al-BMG) powder of composition Al82Fe3Ni8Y7 was synthesized by arc-melting the constituent elements followed by gas-atomization. The particle size and morphology were similar to Fe-BMG with a fully amorphous structure. A small percentage of transition metal constituents (Fe and Ni) in a mostly aluminum alloy showed high catalytic activity, with no toxic by-products and no change in surface characteristics. Al-alloy particles, being light-weight, were easily dispersed in aqueous medium and accelerated the redox reactions. The mechanism of dye dissociation was studied using Raman and Infrared (IR) spectroscopy. Breaking of -C-H- and - C-N- bonds of AZO dye was found to be the primary mechanism. Mechanical behavior of individual BMG particles was evaluated by in situ pico-indentation in a scanning electron ...
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Date: May 2017
Creator: Garrison, Seth Thomas

A Cognitive Radio Application through Opportunistic Spectrum Access

Description: In wireless communication systems, one of the most important resources being focused on all the researchers is spectrum. A cognitive radio (CR) system is one of the efficient ways to access the radio spectrum opportunistically, and efficiently use the available underutilized licensed spectrum. Spectrum utilization can be significantly enhanced by developing more applications with adopting CR technology. CR systems are implemented using a radio technology called software-defined radios (SDR). SDR provides a flexible and cost-effective solution to fulfil the requirements of end users. We can see a lot of innovations in Internet of Things (IoT) and increasing number of smart devices. Hence, a CR system application involving an IoT device is studied in this thesis. Opportunistic spectrum access involves two tasks of CR system: spectrum sensing and dynamic spectrum access. The functioning of the CR system is rest upon the spectrum sensing. There are different spectrum sensing techniques used to detect the spectrum holes and a few of them are discussed here in this thesis. The simplest and easiest to implement energy detection spectrum sensing technique is used here to implement the CR system. Dynamic spectrum access involves different models and strategies to access the spectrum. Amongst the available models, an interweave model is more challenging and is used in this thesis. Interweave model needs effective spectrum sensing before accessing the spectrum opportunistically. The system designed and simulated in this thesis is capable of transmitting an output from an IoT device using USRP and GNU radio through accessing the radio spectrum opportunistically.
Date: May 2017
Creator: Bhadane, Kunal Ashok Ashok

A Community Based Assessment: An Analysis of Community Based Tourism in Kalache and Hulgol, India

Description: This study incorporated a community based assessment with a focus on community based tourism in Kalache and Hulgol, India. Kalache and Hulgol are two agrarian based communities located in the environmentally significant region of the Western Ghats. Each of these communities has considered community based tourism as a means to reduce urban youth outmigration, to diversify economic resources, and to encourage the empowerment of women. The primary goals of this study were to understand the community issues and objectives, to determine the level of support for tourism development, to determine participant attitudes toward tourism, and to determine the obstacles to tourism development. The findings of this project address the complexity of operating in the tourism industry, the impacts of tourism, and the use of community based tourism models in support of sustainable tourism.
Date: May 2017
Creator: Schutz, Michael

A Comparative Evaluation of Matrix Training Arrangements

Description: A common goal of instructional techniques is to teach skills effectively and efficiently. Matrix training techniques are both effective and efficient as they allow for the emergence of untrained responding to novel stimulus arrangements, a phenomenon known as recombinative generalization. However, it is unclear which type of matrix arrangement best promotes recombinative generalization. The current study compared two common matrix training approaches, an overlapping (OV) design and a non-overlapping (NOV) design, with respect to arranging relations targeted for training. We conducted a replication evaluation of a Wilshire and Toussaint study, and taught two typically-developing preschoolers compound object-action labels in Spanish and used either an OV or NOV matrix training design. Results from both studies demonstrated the participant trained with an OV design produced recombinative generalization and participants trained with a NOV design produced significantly low levels of emergence or none at all. These results suggest that an OV matrix design facilitates recombinative generalization more effectively than a NOV design. Implications for instructional arrangements are discussed.
Date: May 2017
Creator: Cliett, Terra N

Comparing Media Usage of Binary and Non-Binary Transgender Individuals when Discovering and Describing Gender Identity

Description: This study was conducted through in-depth interviews to examine potential differences between binary-aligned transgender individuals and non-binary individuals in regards to media usage when learning about, articulating, and explaining their gender identity. Results showed numerous differences between transgender people with binary-aligned and non-binary gender identifications in regards to social media preferences and differences in perceived media importance and effects. Additional information was found in regards to the age at which gender identity is articulated and the importance of individuality in comparison to one's gender identity.
Date: May 2017
Creator: Laljer, David B

A Constructional Approach to Establishing and Maintaining Calm Canine Behavior

Description: Very few behavior-change programs with canines produce effects that persist beyond the training condition. The present study is an experimental demonstration of a constructional program that established calm patterns of behavior as alternatives to hyperactive ones. Three dogs that exhibited hyperactive patterns were chosen as subjects. Seven conditions common to canine-caretaker relationships were used to determine which factors resulted in the hyperactive patterns. Then, sitting and lying down were taught as beginning points using touch as a reinforcer. The final behavior, maintained by naturally occurring reinforcers, was established errorlessly. The study used a control-analysis strategy of behavior change with a changing-criterion design. The intervention resulted in an immediate reduction in hyperactivity and an increase in sitting and lying down for all dogs.
Date: May 2017
Creator: Owens, Chase

Creating Discussion: An Auteur Analysis of Films Directed by Adrian Lyne

Description: This thesis examines the various "signature" threads that are present within the "oeuvre" of the Hollywood filmmaker Adrian Lyne. The goal of this thesis is to showcase both how and why Lyne can be thought of as an auteur and to open up his films to new and previously unexplored meanings. Lyne's eight feature films are analyzed in-depth individually and in comparison to one another from a variety of theoretical frameworks and points of focus in each of the body chapters.
Date: May 2017
Creator: Oliver, Stephanie Renee

Design, Modeling, and Experiment of a Piezoelectric Pressure Sensor based on a Thickness-Shear Mode Crystal Resonator

Description: This thesis presents the design, modeling, and experiment of a novel pressure sensor using a dual-mode AT-cut quartz crystal resonator with beat frequency analysis based temperature compensation technique. The proposed sensor can measure pressure and temperature simultaneously by a single AT-cut quartz resonator. Apart from AT-cut quartz crystal, a newly developed Langasite (LGS) crystal resonator is also considered in the proposed pressure sensor design, since LGS can operate in a higher temperature environment than AT-cut quartz crystal. The pressure sensor is designed using CAD (computer aided design) software and CAE software - COMSOL Multiphysics. Finite element analysis (FEA) of the pressure sensor is performed to analyze the stress- strain of the sensor's mechanical structure. A 3D printing prototype of the sensor is fabricated and the proposed sensing principle is verified using a force-frequency analysis apparatus. Next to the 3D printing model verification, the pressure sensor with stainless steel housing has been fabricated with inbuilt crystal oscillator circuit. The oscillator circuit is used to excite the piezo crystal resonator at its fundamental vibrational mode and give the frequency as an output signal. Based on the FEA and experimental results, it has been concluded that the maximum pressure that the sensor can measure is 45 (psi). The pressure test results performed on the stainless steel product shows a highly linear relationship between the input (pressure) and the output (frequency).
Date: May 2017
Creator: Pham, Thanh Tuong

Design of a Lower Extremity Exoskeleton to Increase Knee ROM during Valgus Bracing for Osteoarthritic Gait

Description: Knee osteoarthritis (KOA) is the primary cause of chronic immobility in populations over the age of 65. It is a joint degenerative disease in which the articular cartilage in the knee joint wears down over time, leading to symptoms of pain, instability, joint stiffness, and misalignment of the lower extremities. Without intervention, these symptoms gradually worsen over time, decreasing the overall knee range of motion (ROM) and ability to walk. Current clinical interventions include offloading braces, which mechanically realign the lower extremities to alleviate the pain experienced in the medial compartment of the knee joint. Though these braces have proven effective in pain management, studies have shown a significant decrease in knee ROM while using the brace. Concurrently, development of active exoskeletons for rehabilitative gait has increased within recent years in efforts to provide patients with a more effective intervention for dealing with KOA. Though some developed exoskeletons are promising in their efficacy of fostering gait therapy, these devices are heavy, tethered, difficult to control, unavailable to patients, or costly due to the number of complicated components used to manufacture the device. However, the idea that an active component can improve gait therapy for patients motivates this study. This study proposes the design of an adjustable lower extremity exoskeleton which features a single linear actuator adapted onto a commercially available offloading brace. This design hopes to provide patients with pain alleviation from the brace, while also actively driving the knee through flexion and extension. The design and execution of this exoskeleton was accomplished by 3D computer simulation, 3D CAD modeling, and rapid prototyping techniques. The exoskeleton features 3D printed, ABS plastic struts and supports to achieve successful adaptation of the linear actuator to the brace and an electromechanical system with a rechargeable operating capacity of 7 hours. Design validation was ...
Date: May 2017
Creator: Cao, Jennifer M

Determining Whether and When People Participate in the Events They Tweet About

Description: This work describes an approach to determine whether people participate in the events they tweet about. Specifically, we determine whether people are participants in events with respect to the tweet timestamp. We target all events expressed by verbs in tweets, including past, present and events that may occur in future. We define event participant as people directly involved in an event regardless of whether they are the agent, recipient or play another role. We present an annotation effort, guidelines and quality analysis with 1,096 event mentions. We discuss the label distributions and event behavior in the annotated corpus. We also explain several features used and a standard supervised machine learning approach to automatically determine if and when the author is a participant of the event in the tweet. We discuss trends in the results obtained and devise important conclusions.
Date: May 2017
Creator: Sanagavarapu, Krishna Chaitanya

Development of an Outcome Measure for Use in Psychology Training Clinics

Description: The ability to monitor client change in psychotherapy over time is vital to quality assurance in service delivery as well as the continuing improvement of psychotherapy research. Unfortunately, there is not currently a comprehensive, affordable, and easily utilized outcome measure for psychotherapy specifically normed and standardized for use in psychology training clinics. The current study took the first steps in creating such an outcome measure. Following development of an item bank, factor analysis and item-response theory analyses were applied to data gathered from a stratified sample of university (n = 101) and community (n = 261) participants. The factor structure did not support a phase model conceptualization, but did reveal a structure consistent with the theoretical framework of the research domain criteria (RDoC). Suggestions for next steps in the measure development process are provided and implications discussed.
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Date: May 2017
Creator: Davis, Elizabeth C.

Development of von Willebrand Factor Zebrafish Mutant Using CRISPR/Cas9 Mediated Genome Editing

Description: von Willebrand factor (VWF) protein acts in the intrinsic coagulation pathway by stabilizing FVIII from proteolytic clearance and at the site of injury, by promoting the adhesion and aggregation of platelets to the exposed subendothelial wall. von Willebrand disease (VWD) results from quantitative and qualitative deficiencies in VWF protein. The variability expressivity in phenotype presentations is in partly caused by the action of modifier genes. Zebrafish has been used as hemostasis animal model. However, it has not been used to evaluate VWD. Here, we report the development of a heterozygote VWF mutant zebrafish using the genome editing CRISPR/Cas9 system to screen for modifier genes involved in VWD. We designed CRISPR oligonucleotides and inserted them into pT7-gRNa plasmid. We then prepared VWF gRNA along with the endonuclease Cas9 RNA from Cas9 plasmid. We injected these two RNAs into 1-4 cell-stage zebrafish embryos and induced a mutation in VWF exon 29 of the zebrafish with a mutagenesis rate of 16.6% (3/18 adult fish). Also, we observed a germline transmission with an efficiency rate of 5.5% (1/18 adult fish). We obtained a deletion in exon 29 which should result in truncated VWF protein.
Date: May 2017
Creator: Toffessi Tcheuyap, Vanina

"Don't Frack with Denton"

Description: Don't Frack With Denton chronicles the ground-breaking movement to ban hydraulic fracturing in the city of Denton, Texas by combining observational location shooting with extensive sit-down interviews and carefully negotiated subject-filmmaker relationships to create a safe and comfortable space for thoughtful reflection and criticism of a complex social movement who's activities span several years and many individuals. The result is a long-form documentary that is unapologetically in solidarity with this movement's goals while simultaneously maintaining enough editorial independence and critical distance to allow the activists themselves to honestly evaluate their decision-making, tactics and interpersonal relationships in ways that will provide insight and instruction to similar movements around the country and the world.
Date: May 2017
Creator: Graham, Garrett

EEG Signal Analysis in Decision Making

Description: Decision making can be a complicated process involving perception of the present situation, past experience and knowledge necessary to foresee a better future. This cognitive process is one of the essential human ability that is required from everyday walk of life to making major life choices. Although it may seem ambiguous to translate such a primitive process into quantifiable science, the goal of this thesis is to break it down to signal processing and quantifying the thought process with prominence of EEG signal power variance. This paper will discuss the cognitive science, the signal processing of brain signals and how brain activity can be quantifiable through data analysis. An experiment is analyzed in this thesis to provide evidence that theta frequency band activity is associated with stress and stress is negatively correlated with concentration and problem solving, therefore hindering decision making skill. From the results of the experiment, it is seen that theta is negatively correlated to delta and beta frequency band activity, thus establishing the fact that stress affects internal focus while carrying out a task.
Date: May 2017
Creator: Salma, Nabila