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Saudi Male Athletes' Experience Using Mental Skills and Attitudes toward Seeking Psychological Assistance in Sport (open access)

Saudi Male Athletes' Experience Using Mental Skills and Attitudes toward Seeking Psychological Assistance in Sport

The primary aim of this research was to assess Saudi Arabian male athletes' attitudes toward seeking sport psychology services and determine their previous experience using mental skills. As a part of the study, an Arabic version of the Sport Psychology Attitudes – Revised form (SPA-R) was developed. Transcultural translation procedures (e.g., back translation) were used to translate the SPA-R into Arabic version. Saudi male athletes (N = 222) ranging from 17 to 25 years of age with various individual and team sport experiences completed the Arabic version of SPA-R survey twice over two-weeks. Exploratory factor analysis indicated that the original theoretical structure of the phenomena existed in the version created for Arabian athletes. Follow-up analyses revealed that Saudi male athletes had high sport psychology consultant confidence and personal openness, moderately high cultural preferences, and low in stigma tolerance. Although the Arabic version of SPA-R may be useful for assessing Saudi male athletes, further research is needed with different Arab populations to verify the factor structure of the observed constructs.
Date: May 2022
Creator: Abdulshakur, Alhassan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Gradient-Index Metamaterial Infrared Detector for Enhanced Photo-Response and Image Quality (open access)

Gradient-Index Metamaterial Infrared Detector for Enhanced Photo-Response and Image Quality

An enhanced thermal imaging concept made possible through the development of a gradient-indexed metamaterial infrared detector that offers broadband transmission and reflection in THz waves. This thesis proposes a proof of feasibility for a metamaterial infrared detector containing an anti-reflective coating with various geometrically varying periodic metasurfaces, a gradient-indexed dielectric multilayer for near-perfect longpass filtering, and a gradient index of refraction (GRIN) metalens for enhanced focal plane thermal imaging. 2D Rigorous Coupled-Wave Analysis (RCWA) is used for understanding the photonic gratings performance based on material selection and varying geometric structure. Finite Difference Time Domain (FDTD) is used to characterize performance for a diffractive metalens by optimizing the radius and arrangement of cylindrical nanorods to create a desired phase profile that can achieve a desired focal distance for projections on a detector for near- to far-infrared thermal imaging. Through combining a micromachined anti-reflective coating, a near-perfect longpass filter, and metamaterial GRIN metalens, infrared/THz focal plane thermal imaging can obtain faster photo-response and image quality at targeted wavelengths, which allows for scientific advancements in electro-optical devices for the Department of Defense, aerospace, and biochemical detection applications.
Date: May 2022
Creator: Adams, Kelsa Derek
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Character

Access: Use of this item is restricted to the UNT Community
Works of art on Wood (Maple plywood), Wood Dye, Recycled cotton yarn, and tufting cloth by artist Atinuke Adeleke as part of a 2023 MFA exhibition entitled "Asepo" in the North Cora Stafford Gallery. 1201 W Mulberry St, Denton, TX from April 19 to April 22, 2023. Asepo is a simulated domestic space that speaks to being a product of the hybridization of cultures, the sense of displacement and the need for belonging that comes with being a hybrid of sorts.
Date: 2022
Creator: Adeleke, Atinuke
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Inner Head

Access: Use of this item is restricted to the UNT Community
Works of art in Acrylic print, by artist Atinuke Adeleke, as part of a 2023 MFA exhibition entitled "Asepo" in the North Cora Stafford Gallery 1201 W Mulberry St, Denton, TX, from April 19 to April 22, 2023.Asepo is a simulated domestic space that speaks to being a product of the hybridization of cultures, the sense of displacement, and the need for belonging that comes with being a hybrid of sorts.
Date: 2022
Creator: Adeleke, Atinuke
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Pot of Different Skins

Access: Use of this item is restricted to the UNT Community
Works of art in Wood (MDF), Metal (Pewter), Wood Dye, Recycled cotton yarn, and Backing cloth by artist Atinuke Adeleke, as part of a 2023 MFA exhibition entitled "Asepo" in the North Cora Stafford Gallery 1201 W Mulberry St, Denton, TX, from April 19 to April 22, 2023. Asepo is a simulated domestic space that speaks to being a product of the hybridization of cultures, the sense of displacement, and the need for belonging that comes with being a hybrid of sorts.
Date: 2022
Creator: Adeleke, Atinuke
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Self Portrait

Access: Use of this item is restricted to the UNT Community
Works of art in Custom printed fabric, Wood (MDF), Clear Acrylic sheet, Acrylic Rods, Pewter, LED lights, by artist Atinuke Adeleke, as part of a 2023 MFA exhibition entitled "Asepo" in the North Cora Stafford Gallery, 1201 W Mulberry St, Denton, TX from April 19 to April 22, 2023. Asepo is a simulated domestic space that speaks to being a product of the hybridization of cultures, the sense of displacement, and the need for belonging that comes with being a hybrid of sorts.
Date: 2022
Creator: Adeleke, Atinuke
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Tales by Moonlight: An Exploratory Analysis of the Effects of a Storytelling Interview Package for Youths and Elders in an Historically Black Community (open access)

Tales by Moonlight: An Exploratory Analysis of the Effects of a Storytelling Interview Package for Youths and Elders in an Historically Black Community

Storytelling is a practice that is used to pass down important information about culture, environment, and history. From a behavior analytic perspective, the process of storytelling involves contingencies and can be viewed within the framework of the Skinner's analysis of verbal behavior. For each listener, based on their history of learning and experiences, stories enable a unique type of learning about reinforcers, punishers and cultural context. In African American oral tradition, storytelling was and still is important in preserving the identity, safety, and wellbeing of African Americans. The purpose of this project was to inductively explore story telling between youth and elders in an African American community. A training workshop was developed that included an overview of the importance and role of storytelling in the black community and ways for youth to respectfully listen and learn from elders. The participants included two children and one elder. The independent variable was the training package, the dependent measures included the levels of synchronous engagement, the listener behaviors of the youth and the participant voices, that is, the descriptions and reflections of children and elders about the process and outcomes of this project. A multiple probes design across skills with in-vivo generalization check …
Date: August 2022
Creator: Akinwale, Oluwabukola Elizabeth
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Processing and Shape-Setting of Shape Memory Alloys for Small Satellite Antennas

In this study, four different NiTi-based shape memory alloys (SMAs) compositions were processed, shape-set, and characterized to evaluate their effectiveness as SMA actuation component for satellite antennas. Three of the compositions were commercially available NiTi wires (90°C Flexinol® actuator NiTi wire and Confluent ADB SE508 NiTi wire), NiTi SM495 plates (ATI Specialty Alloys and Components) and the other composition was in house lab-produced NiTiCu plate. Different shape-setting techniques were performed such as pin and plate, fixtures and dies, and finally a sandwich fixture. The two most promising outcomes were the SE NiTi 508 wire and the NiTiCu plate. A SE NiTi 508 wire was first heat-treated at 550 °C for 3 hours and then it was shape-set at 450 °C for 30 min using a Cu tube which was previously deformed to the desired deployment curvature and fixed on a steel rig. The wire was kept inside the Cu tube during the shape-setting process to obtain the desired curvature. After shape-setting, the wire was thermally cycled multiple times. The results showed that the SE NiTi 508 wire was able to retain its deployment shape successfully after each thermal cycle. Furthermore, a NiTiCu plate was sandwiched between two steel sheets which …
Date: December 2022
Creator: Al Jabri, Nehal Ahmed Mubarak
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Inflammatory Biomarker Levels and Vaccine Response

This study was conducted as part of a parent grantwhich examined the relationship between components of sleep and antibody responses to the flu vaccine in a population of 392 nurses working at two large hospitals. During/after sleep data was collected, nurses had blood drawn at four time points: immediately pre-vaccination, 1-, 6-, and 11-months post vaccine to obtain serum for detection of anti-influenza antibodies measured with an HI (hemagglutination inhibition) assay. Additionally, the inflammatory biomarkers IL6, IL1-β, TNF-α and CRP were measured at the pre-vaccine time point only to determine any correlation between the markers and antibody response. Data was analyzed using a hierarchical regression. In the first step, analyses assessed whether each change/average in cytokines over the one-month period had an impact on vaccine response for each of the four viral strains in the flu vaccine. In a second step, analyses assessed whether variables such as insomnia, stress, age, smoking, BMI, and race had any impact on vaccine response beyond the effects exerted through inflammation. The change in association (β) between the primary independent variable and primary dependent variable were examined in order to determine whether there are any suppression effects caused by baseline covariates on the relationship between …
Date: May 2022
Creator: Alkire, Christopher B
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Localization of UAVs Using Computer Vision in a GPS-Denied Environment (open access)

Localization of UAVs Using Computer Vision in a GPS-Denied Environment

The main objective of this thesis is to propose a localization method for a UAV using various computer vision and machine learning techniques. It plays a major role in planning the strategy for the flight, and acts as a navigational contingency method, in event of a GPS failure. The implementation of the algorithms employs high processing capabilities of the graphics processing unit, making it more efficient. The method involves the working of various neural networks, working in synergy to perform the localization. This thesis is a part of a collaborative project between The University of North Texas, Denton, USA, and the University of Windsor, Ontario, Canada. The localization has been divided into three phases namely object detection, recognition, and location estimation. Object detection and position estimation were discussed in this thesis while giving a brief understanding of the recognition. Further, future strategies to aid the UAV to complete the mission, in case of an eventuality, like the introduction of an EDGE server and wireless charging methods, was also given a brief introduction.
Date: May 2022
Creator: Aluri, Ram Charan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Leaving the Community: A Qualitative Study of Hijra Individuals in Bangladesh (open access)

Leaving the Community: A Qualitative Study of Hijra Individuals in Bangladesh

The hijra community individuals are one of the most neglected and underprivileged sexual minority groups in Bangladesh. Historically this community has been excluded from mainstream society and was compelled to live and work in separate communal spaces. However, new policies of inclusion implemented by government and non-government organizations have resulted in many hijra individuals leaving their communities. In this research, I focused on how the hijra individuals of Bangladesh come out of their hijra communities to find work and accommodation in mainstream society. Based on 11 in-depth ethnographic field interviews and qualitative data analysis, I found that after leaving the community, the hijra individuals living in Dhaka enter a gendered borderland where they occupy a unique outsider-within position. They undertake different survival strategies to survive amongst harsh socio-economic conditions intersected by multiple modes of discrimination such as maintaining a new guru (leader) for social protection, developing support networks, and redefining their gender identity as ‘transgender,' provide the tools to survive life outside their community. Through these findings, I reflect on the ways poor sexual minority groups such as the hijra survive and use their limited resources to find access to housing and informal work. These findings will add to the …
Date: December 2022
Creator: Anandita, Prapti
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Developing a Generalizable Two-Input Genetic AND Logic Gate in Arabidopsis thaliana for Multi-Signal Processing

With effective engineering using synthetic biology approaches, plant-based platforms could conceivably be designed to minimize the production costs and wastes of high-value products such as medicines, biofuels, and chemical feedstocks that would otherwise be uneconomical. Additionally, modern agricultural crops could be engineered to be more productive, resilient, or restorative in different or rapidly changing environments and climates. To achieve these complex goals, information-processing genetic devices and circuits containing multiple interacting parts that behave predictably must be developed. A genetic Boolean AND logic gate is a device that computes the presence or absence of two inputs (signals, stimuli) and produces an output (response) only if both inputs are present. Here, we optimized individual genetic components and used synthetic protein heterodimerizing domains to rationally assemble genetic AND logic gates that integrate two hormonal inputs in whole plants. These AND gates produce an output only in the presence of both abscisic acid and auxin, but not when either or neither hormone is present. Furthermore, we demonstrate the AND gate can also integrate two plant stresses, cold temperature and bacterial infection, to produce a specific response. The design principles used here are generalizable, and therefore multiple orthogonal AND gates could be assembled and rationally …
Date: December 2022
Creator: Anderson, Charles Edgar
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Optimization of Silica Nanocomposite Membranes for Air Dehumidification (open access)

Optimization of Silica Nanocomposite Membranes for Air Dehumidification

This thesis is focused on understanding the correct method to simulate atomistic models to calculate coefficient of diffusion of water through the membrane. It also aims to fix the method previously used in molecular modelling in which the simulation results did not match the experimental results. These membranes will be used in air dehumidification systems. The four types of membranes namely, polyurethane, polyurethane with silica nano particles, polyurethane with silica nano particles and amine surface modifier, and polyurethane with silica nano particles and aniline surface modifier. These membranes were also simulated to understand the effects of temperatures and pressure using molecular dynamics. The software packages used are MAPS 4.3, Avogadro, EMC, OVITO, and LAMMPS. MAPS, Avogadro and EMC were used to model the membrane at an atomistic level while LAMMPS is used to simulate the model generated. OVITO is used to analyze the simulation visually. The movement of water vapor molecules were tracked through the membrane in the simulation and diffusion coefficient was calculated using Mean square displacement equation. To create a realistic model, silica was dispersed in the Polyurethane matrix, simulated under standard atmospheric conditions. These results will help in further optimizing the membrane for air dehumidification. This will …
Date: May 2022
Creator: Appaji, Tejas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Untangling Relational Trauma: A Symptom Network Model of Complex Posttraumatic Stress Disorder within a Relational Framework (open access)

Untangling Relational Trauma: A Symptom Network Model of Complex Posttraumatic Stress Disorder within a Relational Framework

The recent inclusion of complex posttraumatic stress disorder (CPTSD) within the International Classification of Diseases, eleventh edition (ICD-11) prompted scholars to re-evaluate treatment guidelines for traumatic disorders. The present study aimed to conceptualize dyadic, community, and systemic connections within the context of ICD-11 traumatic disorders and investigate unique associations between factors capturing relational quality. The current study additionally utilized a novel network modeling approach to explore the CPTSD symptom network structure using a college sample of trauma survivors. Consistent with generations of theory and research, relational quality factors associated with the disturbances in self-organization (DSO) symptom cluster, and anticipated discrimination associated with both relational disturbance and sense of threat. Affect dysregulation, re-experiencing, and relational engagement emerged as most central within the CPTSD symptom network, providing evidence towards the role of affect regulation in relational functioning, while intersectional discrimination associated with both the PTSD and DSO symptom clusters. Findings from the present study provide context to the potential application of a relational and systems focused intervention.
Date: August 2022
Creator: Archuleta, William P
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of Voluntary and Involuntary Muscle Recruitment Training on the Strength of Isometric Muscle Contractions (open access)

The Effects of Voluntary and Involuntary Muscle Recruitment Training on the Strength of Isometric Muscle Contractions

Approximately 50% of individuals who undergo total knee arthroplasty (TKA) fail to achieve a full functional recovery. Current physical therapy practices commonly utilize neuromuscular electrical stimulation (NMES) to passively activate quadriceps muscles. This passive approach does not directly reteach the lost response, but can strengthen the atrophied muscle. Study 1 compared surface electromyography with biofeedback (sEMGBF) with a changing criterion design to NMES alone. Study 2 compared static sEMGBF to NMES with feedback. Study 3 compared surface electromyography (sEMG) with instructions only to NMES. All other methods were constant across the three studies, where I compared the passive and active approach within-subject, across knees, and across groups while controlling for condition order and leg dominance. Each participant receives both NMES and the shaping procedure. Each condition lasts five minutes and consists of 30 muscle contractions. Each contraction lasts 5 seconds and was followed by a 5 second rest. I compared pre and post adapted maximal voluntary isometric contraction (A-MVIC) tests to determine the effectiveness of each condition. Results of the three studies demonstrated that actively teaching voluntary vastus medialis oblique (VMO) engagement using sEMG is more effective than NMES at increasing maximum voluntary isometric contractions of the VMO.
Date: December 2022
Creator: Armshaw, Gabriel Luke
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Investigation of the Processing-Induced Transition from Shape Memory to Strain Glass of Ni-Ti and Fe-Mn-Al-Cr-Ni Alloys

In this study, we observed the effects of the processing-induced method on two different shape memory alloys (SMAs). First, we compare the transformation behavior of a martensitic NiTi SMA during thermal cycling using wide angle synchrotron radiation X-ray diffraction (WAXS). Based on the thermal cycling results, three observations about processing-induced SGAs as compared to SMAs can be seen: (1) retention of distorted austenite at high and low temperatures, (2) broadening of diffraction peaks in WAXS and disappearance of the thermal peaks in DSC measurements both due to induced strain, and (3) gradual increase in the amount of the martensitic phase. Second, we applied a processing-induced method to a FeMnAlCrNi alloy to examine the possibility of forming a strain glass alloy in an Fe-based system through sufficient dislocation formation via plastic deformation. This alloy was subjected to various percentages of cold work and characterized using scanning electron microscopy, differential scanning calorimetry, Vickers hardness, WAXS data. The results indicate with 50% thickness reduction, stress-free thermal cycling no longer exhibits a measurable phase transformation, suggesting the successful formation of strain glass alloy through sufficient dislocation. The results of this research contribute significantly to the advancement of strain glass alloys (SGAs), especially with respect …
Date: December 2022
Creator: Ashmore, Bailey Nicole
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Fabrication and Testing of Polymeric Flexible Sheets with Asymmetric Distributed Magnetic Particles for Biomedical Actuated Devices

This thesis explores a method to fabricate magnetic membranes with asymmetric distribution of particles and their testing as actuators. Focus of this research is to fabricate thin polymeric sheets and thickness range of 120-125µm, with asymmetric distribution of magnetic nano particles, employing micromagnets during the fabrication. The micromagnets are used to localize the magnetic particles during the curing process at selected locations. The effect of the asymmetric distribution of magnetic particles in the membrane is used for the first time. Magnetite (Fe3O4) is used as the magnetic particles that is embedded into a polymeric membrane made of polydimethylsiloxane (PDMS); the membrane is then tested in terms of deflection observed by using a high-resolution camera. From the perspective of the biomedical application, PDMS is chosen for its excellent biocompatibility and mechanical properties, and Fe3O4 for its non-toxic nature. Since magnetic actuation does not require onboard batteries or other power systems, it is very convenient to use in embedded devices or where the access is made difficult. A comparative study of membranes with asymmetric and randomly distributed particles is carried out in this thesis. The asymmetric distribution of magnetic particles can benefit applications involving localized and targeted treatments and precision medicine.
Date: May 2022
Creator: Bakaraju, Megha Ramya
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Exploring Functional Interdependence of Mands, Tacts, and Intraverbals after Brain Injury (open access)

Exploring Functional Interdependence of Mands, Tacts, and Intraverbals after Brain Injury

One goal of this study was to evaluate the emergence of mands and intraverbals following tact acquisition for individuals with aphasia due to acquired brain injury. A second goal was to evaluate the transfer of shortened latencies as a function of tact training across untrained operants. In Study 1, the dependent measure was accuracy of responding and in Study 2, the dependent measures were rate and latency of responding. Participants for Study 1 were two uninjured adults (pilot) and two adults with brain injury (ABI). Both sets of participants were directly taught to tact up to 6 stimuli. Once tacts were acquired, the response forms were assessed under mand and intraverbal conditions. All pilot participants and one ABI participant showed mand transfer for all stimuli. Tact to intraverbal transfer varied across participants. One adult with brain injury served as a participant for Study 2. Fluency training was used to teach tacts for 15 stimuli. Response latencies were gathered for all operants before and after training. The participant met the designated aim (rate of responding) and showed a decrease in latencies for tacts and untrained intraverbals. Changes in mand latencies varied. Fluency gains showed partial retention. Results from Study 1 provide …
Date: August 2022
Creator: Baltazar-Mars, Marla
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Extended Lydian Locrian Theory of Harmony (open access)

The Extended Lydian Locrian Theory of Harmony

The extended Lydian Locrian theory of harmony (ELL) is a system of analyzing harmonies and progressions according to their position along a vast spectrum of colors. The musical premise is that chords and progressions spanning upwards around the circle of fifths sound brighter, whereas chords and progressions spanning downwards around the circle of fifths sound darker. This simple premise gives rise to a complex but unified system of harmonic structures and relations, a system which provides a valuable tool for analyzing and composing music, especially of advanced tonal genres. ELL not only provides fruitful techniques for analyzing certain kinds of traditional harmonies and progressions but also provides a framework for discovering more exotic and colorful harmonies and progressions.
Date: May 2022
Creator: Bandy, Chris
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Utilization of Telemedicine by People with Chronic Health Conditions during the COVID-19 Pandemic (open access)

Utilization of Telemedicine by People with Chronic Health Conditions during the COVID-19 Pandemic

This study sought to better understand the experiences of individuals with a chronic health condition utilizing telemedicine during the first twelve months of the COVID-19 pandemic. To do this, an online survey was advertised in two private Facebook support groups for individuals with adrenal insufficiency; a chronic health condition that requires frequent communication with healthcare providers. The survey consisted primarily of closed-response questions which examined the demographic data of respondents, their access to healthcare providers, their comfort levels accessing healthcare providers, and the number of times individuals sought healthcare during the first twelve months of the COVID-19 pandemic to try and predict their preference for telemedicine and in-person healthcare visits going forward. Additionally, the survey included open-response questions which allowed for respondents to describe their experience utilizing telemedicine during the first twelve months of the COVID-19 pandemic. Most respondents described their use of telemedicine as being positive but have indicated there are some health circumstances in which telemedicine may not be the best option for them. Additionally, findings indicate that individual's comfort level in visiting their healthcare providers in-person during that first year of the COVID-19 pandemic is a significant predictor of an individual's preference for telehealth. This gives future …
Date: August 2022
Creator: Barker, Tori Saige
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Aristotle on Being Triggered: A Question on Moral Virtue

I argue that Aristotle aids in understanding the tension between the political art and moral virtue through his examination of courage in The Nicomachean Ethics. The end of the political art is to habituate the city and citizens towards "the good." Aristotle examines five held opinions of non-courage, requiring that we reflect on our own vices. I describe how Aristotle prepares his readers for the task of examining the political art. I then view courage found in the citizen and spiritedness as an example of two common opinions where individuals are inclined towards pleasure, as opposed to being inclined to the noble. To conclude, I show that Aristotle provides opinions of non-courage to emphasize how institutions are, and must remain, a foundational part of society.
Date: August 2022
Creator: Barnes, Kenlea Rayne
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Southeast Denton Neighborhood Needs Assessment for Program Evaluation and Development (open access)

Southeast Denton Neighborhood Needs Assessment for Program Evaluation and Development

The intersection of race and space in one neighborhood in Denton, Texas, a college town situated within the greater Dallas-Fort Worth metroplex, reflects the lack of economic opportunities caused by a legacy of racial spatialization. SED, formally known as Solomon Hill, was once a predominately Black enclave; however, the city's population growth has fueled the expansion of the downtown area into neighborhood, transforming it into a hotspot for new investment. As the city rebrands itself in the name of urban entrepreneurialism, SED has become part of revitalization plans that include portraying the neighborhood as part of a cultural district, a tech hub, and an arts district. In order to understand the neighborhood today, we need to first examine its history; therefore, I provide a brief history of racial segregation in SED and examine the power structures that reinforced its marginalization. I then explain how the aforesaid transformation of SED as a cultural district, tech hub, and arts district and the expansion of downtown area into SED is a byproduct of the city's urban entrepreneurialism. Lastly, I discuss the function of the MLK Jr. Recreation Center, and their goals for connecting with the community through program evaluation and development centered around …
Date: December 2022
Creator: Bell, K.D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Stem Cell Regulation Using Nanofibrous Membranes with Defined Structure and Pore Size

Electrospun nanofibers have been researched extensively in the culturing of stem cells to understand their behavior since electrospun fibers mimic the native extracellular matrix (ECM) in many types of mammalian tissues. Here, electrospun nanofibers with defined structure (orientation/alignment) and pore size could significantly modulate human mesenchymal stem cell (hMSC) behavior. Controlling the fiber membrane pore size was predominantly influenced by the duration of electrospinning, while the alignment of the fiber membrane was determined by parallel electrode collector design. Electric field simulation data provided information on the electrostatic interactions in this electrospinning apparatus.hMSCs on small-sized pores (~3-10 µm²) tended to promote the cytoplasmic retention of Yes-associated protein (YAP), while larger pores (~30-45 µm²) promoted the nuclear activation of YAP. hMSCs also displayed architecture-mediated behavior, as the cells aligned along with the fiber membranes orientation. Additionally, fiber membranes affected nuclear size and shape, indicating changes in cytoskeletal tension, which coincided with YAP activity. The mechanistic understanding of hMSC behavior on defined nanofiber structures seeks to advance their translation into more clinical settings and increase biomanufacturing efficiencies.
Date: August 2022
Creator: Blake, Laurence A
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Decision-Making Process of Transitioning to a Regenerative Agricultural System: How Disaster Resilience Fits In (open access)

The Decision-Making Process of Transitioning to a Regenerative Agricultural System: How Disaster Resilience Fits In

Regenerative agriculture, a soil health focused alternative to conventional agriculture, has been increasingly popular among producers and consumers for its ability to produce nourishing food while also prioritizing the health of the environment. The practices used within this style of farming and ranching also have benefits that make operations more resilient to various agricultural hazards. Few studies have addressed the role of resiliency in the transition process to regenerative agriculture. The purpose of this study was to explore the role of disaster resilience in the decision-making process farmers and ranchers use as they transition to regenerative agricultural practices. Drawing from qualitative, semi-structured interviews with Texas ranchers that use regenerative methods, four major themes were found. First, climate related hazards are a recurring issue because agricultural operations are continually threatened by the same hazards. Next, the food system is in dire need of change, as producers recognize a major problem in the food system, and it is leading to a food insecure future. Also prevalent, disaster resilience is a built-in benefit because regenerative practices result in the creation of systems that build resilience. Finally, learning opportunities are expanding as an increased interest in regenerative agriculture is providing more opportunities for both …
Date: August 2022
Creator: Boyle, Cassidy
Object Type: Thesis or Dissertation
System: The UNT Digital Library