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UNT Theses and Dissertations
411
UNT Scholarly Works
56
Journal of Near-Death Studies
18
Photographing Texas
18
University of North Texas Press
16
General Collection
10
Texas Pano Project
8
Dallas/Fort Worth American Chemical Society Publications
7
Texas History for Teachers Resources
6
Texas Catholic Newspaper Collection
5
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Journal of Near-Death Studies
18
JNDS, Volume 39, Number 3
7
Southwest Retort
7
JNDS, Volume 39, Number 2
6
South Texas Catholic
5
JNDS, Volume 39, Number 1
4
UNT Libraries ColorOurCollection Coloring Pages
3
Al Filo; no. 11
1
American Military Studies Series; no. 5
1
American Military Studies; no. 6
1
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Department of Psychology
30
Department of Teacher Education and Administration
27
Department of Biological Sciences
26
Department of Counseling and Higher Education
25
Department of Materials Science and Engineering
20
Division of Instrumental Studies
17
Digital Libraries
16
Department of Educational Psychology
15
Department of English
15
Department of Learning Technologies
15
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549
Algebraic Trait for Structurally Balanced Property of Node and Its Applications in System Behaviors
This thesis targets at providing an algebraic method to indicate network behaviors. Furthermore, for a signed-average consensus problem of the system behaviors, event-triggering signed-average algorithms are designed to reduce the communication overheads. In Chapter 1, the background is introduced, and the problem is formulated. In Chapter 2, notations and basics of graph theory are presented. It is known that the terminal value of the system state is determined by the initial state, left eigenvector and right eigenvector associated with zero eigenvalue of the Laplacian matrix. Since there is no mathematical expression of right eigenvector, in Chapter 3, mathematical expression of right eigenvector is given. In Chapter 4, algebraic trait for structurally balanced property of a node is proposed. In Chapter 5, a method for characterization of collective behaviors under directed signed networks is developed. In Chapter 6, dynamic event-triggering signed-average algorithms are proposed and proved for the purpose of relieving the communication burden between agents. Chapter 7 summarizes the thesis and gives future directions.
Date:
December 2021
Creator:
Du, Wen (Electrical engineering researcher)
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Studies on Tissue Factor Pathway Inhibitor in Zebrafish
Tissue Factor Pathway Inhibitor (TFPI) is an anticoagulant protein containing three Kunitz domains, K1, K2 and K3. K1 inhibits Factor VIIa, K2 inhibits Factor Xa, and K3 enhances the Factor Xa inhibition by its interaction with Protein S. Since zebrafish is an excellent genetic model, we hypothesized that TFPI regulation could be studied using this model. As a first step, we confirmed the presence of tfpia in zebrafish. Subsequently, we performed knockdown of tfpia, and knockout of tfpia in K3 domain using CRISPR/Cas9. Both the tfpia knockdown and tfpia homozygous deletion mutants showed increased coagulation activities. Our data suggest that zebrafish tfpia is an orthologue for human TFPIα, and silencing it results in a thrombotic phenotype. We then optimized the piggyback knockdown method, where we could simultaneously piggyback 3 or 6 ASOs corresponding to 3 or 6 genes, respectively, using one VMO. These multiple gene knockdowns will increase the efficiency of genome-wide knockdowns. Since there are no studies on chromatin remodeling that control TFPI expression, we hypothesized that the genome-wide knockdowns of the Chromatin Binding and Regulatory Proteins (CBRPs) in zebrafish could help identify novel tfpia gene regulators. We chose 69 CBRPs and subjected them to simultaneous gene knockdowns. Our …
Date:
August 2021
Creator:
Raman, Revathi
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Aerodynamic Optimization of a 2D Airfoil for Rotary-Wing Aircraft at Mars Atmospheric Conditions
The interest toward Mars exploration has been considerably increasing due to also the successful deployment of the Perseverance rover and the continuous tests developed by SpaceX's launch vehicle, Starship. While the Mars 2020 mission is currently in progress, the first controlled flight on another planet have been proven in April 2021 with the vertical take-off and landing of the Ingenuity rotorcraft on Mars. In addition, the rotorcraft Dragonfly is expected to achieve the same endeavor in Titan, the largest moon of Saturn, by 2036. Continuous efforts have been oriented toward the development of new technologies and aircraft configurations to improve the performance of current proposed designs to achieve powered flight in different planetary bodies. This thesis work is a preliminary study to develop a comprehensive analysis over the generation of optimum airfoil geometries to achieve vertical flight in environments where low Reynolds numbers and Mach number equal to 0.2 and 0.5.
Date:
December 2021
Creator:
Saez, Aleandro G.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
A Well Dressed Menagerie: Defining and Teaching Courtliness with Animals and Clothing in the Lais of Marie de France
In this dissertation, I explore how the twelfth-century poet Marie de France combines animals and clothing to define and teach noble conduct in her Lais collection. I suggest that the nexus she creates between animals, dress, and virtue is chimeric but consistent, appearing differently in each narrative situation but recurring as a means of demonstrating moral conduct. My chapters explore three of her lais that combine beasts and attire to address the unique way Marie features the animal-clothing combination in each to teach distinctive lessons in virtuous behavior. My chapter on Guigemar argues that Marie uses the magical hind and the exchange of a knotted shirt and a belt to rework Ovidian anti-love themes to teach the value of being tightly bound in loyal love. Chapter 3 analyzes the eponymous knight's removal of his clothing as the mechanism that triggers his appearance as a werewolf in Marie's lai Bisclavret. I show that Bisclavret's werewolf form is like a sartorial skin under which his selfhood remains unaltered rather than a true transformation, and I argue that Marie uses the knight's appearance as a wolf so that the loyalty he demonstrates to his king and his homosocial community becomes voluntary and therefore …
Date:
August 2021
Creator:
Clark, C. Natalie Massie
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Materials Approaches for Transparent Electronics
This dissertation tested the hypothesis that energy transferred from a plasma or plume can be used to optimize the structure, chemistry, topography, optical and electrical properties of pulsed laser deposited and sputtered thin-films of ZnO, a-BOxNy, and few layer 2H-WS2 for transparent electronics devices fabricated without substrate heating or with low substrate heating. Thus, the approach would be compatible with low-temperature, flexible/bendable substrates. Proof of this concept was demonstrated by first optimizing the processing-structure-properties correlations then showing switching from accumulation to inversion in ITO/a-BOxNy/ZnO and ITO/a-BOxNy/2H-WS2 transparent MIS capacitors fabricated using the stated processes. The growth processes involved the optimization of the individual materials followed by growing the multilayer stacks to form MIS structures. ZnO was selected because of its wide bandgap that is transparent over the visible range, WS2 was selected because in few-layer form it is transparent, and a-BOxNy was used as the gate insulator because of its reported atomic smoothness and low dangling bond concentration. The measured semiconductor-insulator interfacial trap properties fall in the range reported in the literature for SiO2/Si MOS structures. X-ray photoelectron spectroscopy (XPS), Hall, photoluminescence, UV-Vis absorption, and X-ray diffraction (XRD) measurements investigated the low-temperature synthesis of ZnO. All films are nanocrystalline with …
Date:
December 2021
Creator:
Iheomamere, Chukwudi E.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Usability Testing for e-Portfolio Websites in an Academic Environment: A Qualitative Study
Many academic institutions are tasked with trying to improve the usability of their online educational support technologies such as ePortfolios, intelligent websites, and other interface technology to make them as efficient as possible to meet the requirements of their end users. This is particularly important for the academic institutions during times and situations when they may not have a live human presence available to respond to various inquiries from their end users about the technology. The challenges of an academic institution in making its ePortfolios viable can cost itself, its end users, as well as its other stakeholders, money, time, and confidence in the technology. This study is about usability testing for improving the user-interface for ePortfolios. This is a qualitative study using the think-aloud protocol (TAP) for data collection and failure modes and effects analysis (FMEA) for data analysis.
Date:
December 2021
Creator:
Reborn, Jaime
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Using a Slopes Difference Test to Probe Longitudinal Multilevel Interactions in an Aptitude-Treatment or Skill-by-Treatment Context: A Simulation
In order to determine which interventions work best for which students, precision education researchers have examined aptitude-treatment interactions (ATI) or skill-by-treatment interactions (STI) by using multiple regression analysis. In recent years, technological innovation and greater accessibility to more advanced statistical techniques have allowed researchers to examine ATI or STI using longitudinal mixed modeling. Probing techniques for interaction effects like slopes difference tests fit well with an ATI or STI framework, but the power of using a slopes difference test in longitudinal mixed models is unknown. The current study used the simulation method to determine which factors influence the power of a slopes difference test in a longitudinal mixed model. Specifically, the study examined design conditions such as number of waves, number of clusters and participants per cluster, effect size, intraclass correlation, variances and covariance of the random effects, and proportion of treatment to non-treatment participants. These were examined in order to help ATI and STI researchers understand whether the slopes difference test in a longitudinal mixed model is sufficiently powered for their sample and study. Effect size, number of waves, number of clusters, and participants per cluster were found to be strong determinants of power and significantly impacted model convergence …
Date:
August 2021
Creator:
DeJong, Trey L.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Nature Study
A collection of poetry concerned with loss and the act of creation.
Date:
December 2021
Creator:
Abercrombie, Benjamin
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
The Balkan Imbroglio: The Diplomatic, Military, and Political Origins of the Macedonian Campaign of World War I
The Macedonian Campaign of World War I (October 1915-November 1918) traditionally remains one of the understudied theatres of the historiography of the conflict. Despite its vital importance in the outcome of the war, it is still considered as a mere sideshow compared to the Western Front and the Gallipoli Campaign. This dissertation presents a much-needed re-evaluation of the Macedonian Campaign's diplomatic and political origins within the war's early context. In doing so, this study first concentrates on a longue durée perspective and assesses the main historical events in the Balkans and Central Europe from the end of the French Revolution to World War I. In a perspective running throughout the entire nineteenth century, this dissertation integrates the importance of nascent nationalism in the Balkans and examine the Austro-Hungarian Empire's steady decline and subsequent diplomatic realignment toward the Balkans. Similarly, this work depicts the intense power struggle in Southeastern Europe between some of this story's main protagonists, namely the Austro-Hungarian, Russian and Ottoman Empires. This dissertation also evaluates the rise of new regional powers such as Bulgaria and Serbia and examines their connection to the European balance of power and general diplomatic equilibrium. In the first half of this dissertation, I …
Date:
August 2021
Creator:
Broucke, Kevin R.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
A Proposal for a Training Program to Support Culturally Responsive Professional-Family Interactions
Behavior analysts often work with families from diverse cultural backgrounds. Ideally, behavior analysts and families interact in ways that are responsive to the family's culture and valued outcomes. The data indicate that most behavior analysts, however, come from one dominant cultural group. This is a proposal for training program and evaluation method to support culturally responsive professional-family interactions. This proposed study is designed to be conducted via Zoom-- a cloud-based video conferencing service. A pre-post treatment design is proposed to assess the effects of the training. Hypothetical data were generated to consider the range of effects such a program might have on trainee responses to written/live scenarios. Responses in the observation protocol included written descriptions, empathetic statements, perspective taking statements, and non-verbal behaviors. Overall, the program was designed using evidence-based procedures and is likely to support behavior analysts in training and in practice to improve their interactions with families and become more culturally responsive to groups of people that are from the non-dominant culture.
Date:
December 2021
Creator:
Anegbeh, Cynthia Momoh
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Real Time Gas Monitoring and Modeling on the Pyrolysis Process of Biomass
In order to better understand the changes occurring in the internal environment of the pyrolysis process a method of monitoring the internal environment in real time is the key objective of this study. To accomplish this objective four tasks were laid out in order to develop an effective way of monitoring the changes in gases present as pyrolysis is occurring as well as in material activation processing. For all processing the self-activation process was used which combines pyrolysis and thermal activation into a single step process. In the first task 10 hard wood species were activated and the resulting properties were compared to see the impact of wood species on the resulting carbon structures. In order to understand the impact of gas concentration on the resulting carbons the second task developed a gas sensor array which effectiveness was corroborated using GC-MS and then comparisons of the changes in the resulting were made. For the third task the gas sensor array was used to analyze the production of CO2 gas and a triple Gaussian model was developed to model the changes in gas production throughout processing. H2 gas production was modeled in the fourth task using the same Gaussian model as …
Date:
December 2021
Creator:
Smith, Lee Miller
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Third Party Actor Interests, Conflict Management Approaches, and Intrastate Conflict Outcomes
This dissertation examines the role of third parties in civil war mediation and peacekeeping efforts. The dissertation makes two primary contributions to the literature. First, it builds upon existing literature by applying state-level arguments of third party involvement in mediation and peacekeeping efforts to the United Nations Security Council and regional IGOs. Second, it investigates the role of communication and coordination between third parties in their conflict management efforts.
Date:
December 2021
Creator:
Mintun, Daniel T.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Influence of Hypoxia on Acute Lead Toxicity and Calcium Homeostasis in Early Life Stage Zebrafish (Danio rerio)
The purpose of this study was to investigate the effects of Pb and hypoxia co-exposure on Pb toxicity and Ca homeostasis in early life stage (ELS) zebrafish (Danio rerio). Previous evidence indicates that exposure of ELS zebrafish to hypoxia (~20% air saturation) reduces Ca uptake, likely through down-regulation of the apical epithelial Ca channel (ECaC). Considering that Pb and Ca are known antagonists and compete for uptake pathways, it was hypothesized that co-exposure of Pb with hypoxia would decrease Pb toxicity by reducing Pb uptake (likely mediated through a reduced number of ECaCs). However, it was shown that at 96 hpf, whole body accumulation of both Pb and Ca was lower at 40% air saturation compared to 100% and 20% air saturation. This result closely aligned with the 96h LC50 results which showed the highest mortality of zebrafish at 40% compared to the other air saturation levels. This suggests that toxicity is likely the result of exacerbated hypocalcemia at 40% air saturation due to both Pb competition for Ca binding to Ca uptake channels/transporters, such as ECaC, and potentially reduced expression of such channels/transporters in response to this level of hypoxia. Overall, it appears that ELS zebrafish respond differentially to …
Date:
December 2021
Creator:
Moghimi, Mehrnaz
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
3D Printing of Zinc Anode for Zinc Ion Batteries
Recently, 3D printing has received increasing attention for the fabrication and assembly of electrodes for batteries due to the freedom of creating structures in any shape or size, porosity, flexibility, stretchability, and chemistry. Particularly, zinc ion batteries (ZIBs) are favored due to high safety, cheap materials cost, and high volumetric capacity (5,849 mAh/cm3), however, rapid evaporation of Zn due to low melting temperature has limited its 3D printability via conventional laser-based additive manufacturing technique. Here, we develop a printable ink for the fabrication of flexible and 3D printed Zn anode with varied surface areas using the direct ink writing (DIW) method. Our 3D printed porous and high surface area Zn anode structures effectively suppressed the dendrite growth while providing high Zn ion diffusion towards the cathode to significantly enhance the performance of ZIB. By varying filament distancing and path, we 3D printed zinc anode structures with different active surface areas, surface area to volume ratio, porosity, flexible and multiple layer structures that can be incorporated on any device. Carbon in the composite improved conductivity, and mechanical stability of 3D printed zinc anode. Our 3D printed composite anodes allowed flexible designing of batteries surpassing conventional battery designs such as coin cells …
Date:
December 2021
Creator:
Amoko, Stephen Adot Oyo
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Annotated Texts of the Languages of the Barak Valley: Thadou, Saihriem, Hrangkhol, Ranglong
This inaugural volume of the CoRSAL Occasional Publications is a collection of traditional and personal texts in Thadou, Saihriem, Hrangkhol, and Ranglong, four languages of the Barak Valley region of Northeast India. The narratives were collected, transcribed, and translated by Dr. Pauthang Haokip, who is an Associate Professor of Linguistics at Jawaharlal Nehru University, Delhi, India and a member of the Thadou community. This text collection includes grammatical analysis presented in the form of interlinear glossing and accompanied by audio recordings in the Languages of the Barak Valley collection in the Computational Resources of South Asian Languages archive. The collection will be of lasting interest to historical, comparative, and typological linguists, as well as speakers connecting or reconnecting with cultural and linguistic traditions.
Date:
2021
Creator:
Haokip, Pauthang; Chelliah, Shobhana Lakshmi; Burke, Mary & Heaton, Marty
Object Type:
Book
System:
The UNT Digital Library
Spatial-Temporal Assessment of Irrigation Application Changes and Soil Moisture Analysis Using SMAP Maps
Due to inadequate long-term and large-scale observation approach for observation of soil moisture across the globe, this study intends to unveil the importance of using simulated soil moisture fields from land surface models, forced with observed precipitation and near-surface meteorology in monitoring drought and formulating effective water management practices for continued production irrigation applications. This study shows that socio-economic and ecosystem effects can be determined by evaluating spatial-temporal changes in irrigation applications. Thus, it facilitates understanding of the importance of water management and how water, energy, and carbon flows protect our climate and environment. By using Soil Moisture Active Passive (SMAP) in monitoring soil moisture, the information obtained is critical in providing early drought warnings, particularly in those parts of the United States that experience flash agricultural droughts. Further, this study highlights that frequent and reliable soil moisture measurements from SMAP helped improve the predictive capability of weather and climate models.
Date:
December 2021
Creator:
Unal, Kerra E.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Forging Pathways: A Multi-Case Study of Individuals with Intellectual Disability Pursuing Postsecondary Education at the Community College
This multi-case study sought to better understand how students with intellectual disability (ID) are forging pathways to higher education via the community college. Five individuals with ID who accessed higher education via the community college and their parents/guardians were interviewed. Each case provided insight into personal pathways with results given in case descriptions and individual case themes. Cross-case analysis revealed four themes positively impacting the college-going pathway for students with ID: value-driven grit, pathway knowledge, community support, and accessibility. Based on findings from this study, families appear to be the primary systems forging pathways to the community college for individuals with ID. Local education agencies and community colleges can assist these families by engaging in interagency collaboration, evaluating their systems, and aligning practices to the goal of students with ID accessing and engaging in higher education.
Date:
December 2021
Creator:
Jackson, Amanda O.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Investigating the Effects of Inhaled Diesel Exhaust Particles on Gut Microbiome, Intestinal Integrity, Systemic Inflammation, and Biomarkers of Cardiovascular Disease in Wildtype Mice
We investigated the hypothesis that exposure to inhaled diesel exhaust PM can alter the gut microbiome and intestinal integrity, thereby promoting systemic inflammatory response and early CVD risk, which are exacerbated by HF diet. Furthermore, we investigated whether the observed exposure and diet-mediated outcomes could be mitigated through probiotic treatment. We performed an exposure study on C57Bl/6 male mice, placed on either a low fat (LF) diet or a high-fat (HF) diet, and exposed via oropharyngeal aspiration to 35 μg diesel exhaust particles (DEP) suspended in 35 μl of sterile saline or sterile saline controls (CON) twice a week for four weeks. A subset of mice on HF diet were dosed with 0.3 g/day (PRO, ~7.5x108 CFU/day) of probiotic Ecologic® Barrier 849 (Winclove Probiotics) in drinking water during the course of the study. For our first aim, we investigated the alterations in the gut microbiome, measured circulating cytokines and lipopolysaccharide (LPS), and measured CVD biomarkers in the heart. Our results revealed that exposure to inhaled DEP results in gut dysbiosis characterized by expansion of the phyla Verrucomicrobia and Proteobacteria and reduction in Actinobacteria, which was exacerbated by HF diet. Probiotics mitigated the DEP-mediated expansion of Proteobacteria and re-established Actinobacteria in …
Date:
December 2021
Creator:
Phillippi, Danielle T.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Reliability Characterization and Performance Analysis of Solid State Drives in Data Centers
NAND flash-based solid state drives (SSDs) have been widely adopted in data centers and high performance computing (HPC) systems due to their better performance compared with hard disk drives. However, little is known about the reliability characteristics of SSDs in production systems. Existing works that study the statistical distributions of SSD failures in the field lack insights into distinct characteristics of SSDs. In this dissertation, I explore the SSD-specific SMART (Self-Monitoring, Analysis, and Reporting Technology) attributes and conduct in-depth analysis of SSD reliability in a production environment with a focus on the unique error types and health dynamics. QLC SSD delivers better performance in a cost-effective way. I study QLC SSDs in terms of their architecture and performance. In addition, I apply thermal stress tests to QLC SSDs and quantify their performance degradation processes. Various types of big data and machine learning workloads have been executed on SSDs under varying temperatures. The SSD throughput and application performance are analyzed and characterized.
Date:
December 2021
Creator:
Liang, Shuwen (Computer science and engineering researcher)
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Remotely Controlled Magneto-Phononic Devices Achieving Nonreciprocity and Anderson Localization in Ferrofluid
Motivated by previous relevant research on phononics including both active and passive phononics, the interest of faster turnability and more functions of the active phononics of further study led to this proposing research topic: magnetic field tunable active functional phononics. The first design of magnetic field tunable reciprocal--non-reciprocal transmission acoustic device was established, material was characterized, and numerical simulation has been performed. The simulation results show clear T-symmetric breaking non-reciprocity due to energy level splitting effect with Doppler effect – an acoustic Zeeman effect. Inspired by this preliminary work, further experiments were planned to demonstrate this effective Zeeman effect in phononics and effectively charged phonons in water based ferro-fluid. The objectives of this work as the next series of tasks were to illustrate acoustic Zeeman effect and acoustic Landau levels in various strength of magnetic field to investigate a design non-reciprocal sound device with magnetic field switching, which could be controlled on the amount of non-reciprocity with the strength of magnetic field. Once this new field first discovered by the proposed study tasks, more active tunable magnetic field phononics devices could be designed and exemplified in terms of both simulations and experiments. Faster and more controllable active phononic devices could …
Date:
December 2021
Creator:
Jin, Yuqi
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Reduced Visceral Fat and Biological Indices of Inflammation Following Combined Prebiotic/Probiotic Supplementation in Free Living Adults
Probiotics/prebiotic supplementation represents a viable option for addressing systemic inflammation and chronic disease risk resulting from excessive body weight. The purpose of this feasibility study was to determine if 90-d of supplementation with prebiotic and probiotic could alter mRNA responsible for inflammation and subsequently metabolic health in weight stable overweight adults. Participants were advised to not change their diet or exercise habits during the study. All protocols were approved by the University IRB and participants gave written informed consent. Participants were randomly assigned to either placebo (N=7; rice flour) or combined (N=8) prebiotic (PreticX® Xylooligosaccharide; 0.8 g/d; ADIP) and probiotic (MegaDuo® Bacillus subtilis HU58 and Bacillus coagulans SC-208; 3 Billion CFU/d) and measurements were made at baseline, 30, 60, and 90-d. Whole body DXA scans (GE iDXA®) and blood 574-plex mRNA analysis (Nanostring®) were used to generate primary outcomes. Compared to placebo, supplementation was associated with a 36% reduction in visceral adipose tissue (p = 0.001). Supplement resulted in significant, differential expression of 15 mRNA associated with adipose tissue inflammation, systemic inflammation, and/or chronic disease risk. The key findings support that 90-d prebiotic/probiotic supplementation may be associated with an improved metabolic health, reduced adipose tissue inflammation, reduced systemic inflammation, and …
Date:
December 2021
Creator:
Tanner, Elizabeth A.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library