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Health Reform Implementation Analysis: A Guide to Policy Development for Geriatric Care Planning, Integration and Evaluation

In the context of health care delivery for senior citizens, this research utilizes three studies that examine the development and implementation of health policy and the factors that can directly or indirectly impact the effective delivery of health services to senior citizens. It utilizes three essays employing mixed methods (qualitative and quantitative) methods including semi structured interviews, multiple regression and partial least squares structural equation modelling to examine the extent to which the implementation of health services delivered attributes of primary and integrated care to seniors. The two essays identified methods, approaches and strategies of integrated care relevant to the development of policy that can be successfully implemented when the contextual issues that older people consider to be important in maintaining their functional capabilities and their motivation to improve health as perceived by them are addressed. Consequent upon the results from these studies, the third essay examines the methodological issues on integrated geriatric care implementation when guidelines for effective policy development identified were not followed. By highlighting the relationship between effective policy and patient satisfaction, these three essays' recommended approach enhances the theory of health design that confirms that theoretical models of primary care must incorporate the system, process and …
Date: August 2020
Creator: Abah, Theresa
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Stimulus Control Effects of Changes in Schedules of Reinforcement (open access)

Stimulus Control Effects of Changes in Schedules of Reinforcement

Sometimes, changes in consequences are accompanied by a clear stimulus change explicitly arranged by the experimenter. Other times when new consequences are in effect, there is little or no accompanying stimulus change explicitly arranged by the experimenter. These differences can be seen in the laboratory as multiple (signaled) schedules and mixed (unsignaled) schedules. The current study used college students and a single-subject design to examine the effects of introducing signaled and unsignaled schedules, and the transitions between them. In one phase, a card was flipped from purple to white every time the schedule was switched from VR-3 to FT-10. In another phase, the schedule still changed periodically, but the card always remained on the purple side. Results showed that the participants' responding was controlled by the schedule of reinforcement, by the color of the card, or both. These results suggest that changes in patterns of reinforcement lead to changes in stimulus control. In addition, the stimulus control for a behavior can come from several different sources. During teaching, it may facilitate the development of stimulus control to change the environment when a new behavior is required.
Date: August 2020
Creator: Abdel-Jalil, Awab
Object Type: Thesis or Dissertation
System: The UNT Digital Library
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

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

Impact of Anti-S2 Peptides on a Variety of Muscle Myosin S2 Isoforms and Hypertrophic Cardiomyopathy Mutants Revealed by Fluorescence Resonance Energy Transfer and Gravitational Force Spectroscopy

Myosin subfragment-2 (S2) is an intrinsically unstable coiled coil. This dissertation tests if the mechanical stability of myosin S2 would influence the availability of myosin S1 heads to actin thin filaments. The elevated instability in myosin S2 coiled coil could be one of the causes for hypercontractility in Familial Hypertrophic Cardiomyopathy (FHC). As hypothesized FHC mutations, namely E924K and E930del, in myosin S2 displayed an unstable myosin S2 coiled coil compared to wild type as measured by Fluorescence Resonant Energy Transfer (FRET) and gravitational force spectroscopy (GFS). To remedy this, anti-S2 peptides; the stabilizer and the destabilizer peptides by namesake were designed in our lab to increase and decrease the stability of myosin S2 coiled coil to influence the actomyosin interaction. Firstly, the effectiveness of anti-S2 peptides were tested on muscle myosin S2 peptides across MYH11 (smooth), MYH7 (cardiac), and MYH2 (skeletal) with GFS and FRET. The results demonstrated that the mechanical stability was increased by the stabilizer and decreased by the destabilizer across the cardiac and skeletal myosin S2 isoform but not for the smooth muscle isoform. The destabilizer peptide had dissociation binding constants of 9.97 × 10-1 μM to MYH7 isoform, 1.00 μM to MYH2 isoform, and no …
Date: August 2020
Creator: Aboonasrshiraz, Negar
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Pressure Controlled Topochemical Polymerization in Two-Dimensional Hybrid Perovskite

Mechanical pressure offers unique control over the energy landscape of chemical reactions, opening up pathways that are inaccessible through conventional thermochemistry. We hypothesize that the reduced dimensionality defines the conformational space of the high-pressure reaction, giving rise to new selectivity that is unavailable in 3D systems. Here, we demonstrate this concept through the pressure-controlled topochemical polymerization of the diacetylene molecule deca‐3,5‐diyn‐1‐amine (DDA) incorporated in the two-dimensional (2D) perovskite [DDA]2PbBr4. Compression at 3 GPa drives the first topochemical polymerization through 1,2 addition, forming a polyene product at room temperature. The reaction is initiated by the mechanical bending of the linear DDA molecule, a mechanism fundamentally different from the 1,4-addition in 3D solids. Importantly, pressure hinders the second 1,2-addition by disfavoring the gauche conformation between the remaining acetylene groups, allowing for the selective formation of polyene versus polyacene products. We characterize the reaction mechanisms and products using spectroscopies (Raman, X-ray photoelectron, ultraviolet-visible), X-ray diffraction and density-functional theory simulations. These results highlight the important role of dimensionality in high-pressure chemistry, and offers a new paradigm for creating low-dimensional functional materials.
Date: December 2021
Creator: Abu-Amara, Lama Marwan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Neural Network Classifiers for Object Detection in Optical and Infrared Images (open access)

Neural Network Classifiers for Object Detection in Optical and Infrared Images

This thesis presents a series of neural network classifiers for object detection in both optical and infrared images. The focus of this work is on efficient and accurate solutions. The thesis discusses the evolution of the highly efficient and tiny network Binary Classification Vision Transformer (BC-ViT) and how through thoughtful modifications and improvements, the BC-ViT can be utilized for tasks of increasing complexity. Chapter 2 discusses the creation of BC-ViT and its initial use case for underwater image classification of optical images. The BC-ViT is able to complete its task with an accuracy of 99.29\% while being comprised of a mere 15,981 total trainable parameters. Chapter 3, Waste Multi-Class Vision Transformer (WMC-ViT), introduces the usefulness of mindful algorithm design for the realm of multi-class classification on a mutually exclusive dataset. WMC-ViT shows that the task oriented design strategy allowed for a network to achieve an accuracy score of 94.27\% on a five class problem while still maintaining a tiny parameter count of 35,492. The final chapter demonstrates that by utilizing functional blocks of BC-ViT, a simple and effective target detection algorithm for infrared images can be created. The Edge Infrared Vision Transformer (EIR-ViT) showed admirable results with a high IoU …
Date: December 2023
Creator: Adams, Ethan Richard
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Adolescent Self-Theories of Singing Ability within the Choral Hierarchy

The purpose of this study was to explore adolescent self-views of singing ability through both implicit theories and self-concept meaning systems. A secondary purpose of this study was to examine these self-views specifically in the context of a choral hierarchy. Using a researcher-designed survey instrument, I gathered data from middle- and high-school students currently enrolled in a choir program organized in a hierarchical structure. I analyzed descriptive statistics of survey responses to items designed to measure implicit theories of singing ability, singing self-concept, and goal orientation. I also examined differences among participants by ensemble placement in implicit theory and self-concept scores, correlation between implicit theory and self-concept, and whether implicit theory, self-concept, goal orientation, or current enrollment could predict future enrollment decisions. In addition to these quantitative measures, I coded open-ended responses to two failure scenarios and examined participant responses by ensemble and gender. Both implicit theory and self-concept scores were higher for participants at the top of the choral hierarchy than at the bottom. Open-ended responses, however, did not align with the implicit theory scale and a number of students presented a false growth mindset. Open-ended responses also indicated that failure scenarios were likely to result in an altered …
Date: May 2020
Creator: Adams, Kari
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
"The military unlocked that door for me": Collegiate Experiences of Women Veterans in STEM Majors (open access)

"The military unlocked that door for me": Collegiate Experiences of Women Veterans in STEM Majors

Institutions of higher education are a key pathway for supplying the science, technology, engineering, and mathematics (STEM) workforce. Military service members have been identified as STEM-ready and a potential pool for STEM as they transition into civilian careers. Furthermore, women are the fastest growing subpopulation of veterans and may decrease the gender gap within STEM. Higher education researchers are interested in understanding the characteristics and experiences of students who select STEM majors and then persist to graduation. Literature related to women veterans is limited and a qualitative case study approach was utilized to achieve an in-depth understanding of their college experiences. This study examined four women who were successfully navigating STEM majors at one institution and revealed their varying motivations for enrollment and persistence. Three themes generated from this study included: self-awareness, success is personal, and military experience matters. Subsidiary themes included starting over; strategy; salience of age; stage of life; self-advocacy; standards; personal attributes; past experiences; personal responsibility for learning; procuring resources; career path (STEM) reinforced or introduced; creditable and credible; and cultivated soft skills. Veteran critical theory, multiple dimensions of identity and intersectionality were useful frameworks to reference as participants expressed the influence of their identities on their …
Date: May 2022
Creator: Adams, Lisa Dawn
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Exploring the Impact of Decentralization of Decision Making and Complexity on Supply Chain Resilience

The purpose of this three-essay dissertation is to synthesize and extend the effects of decentralization in decision-making and supply chain complexity in the context of supply chain resilience (SCRES).First essay contributes to theory and practice by expanding resilience thinking into including supply chain orientation and organizational structure and their implications and also responds to prior research arguing for the importance of identifying organizational factors that improve supply chain resilience. Second essay contributes to the supply chain organizational structure and SCRES literature by not just providing empirical support for decentralization of decision making in times of disruptions but more precisely by showing the factors that either impede or facilitate decentralization at the organizational level. Understanding the interplay among these factors is critical to explaining the lack of success for decentralization in the context of SCRES. Third essay contributes to practice by reviewing some of the major complexity drivers present in the supply chains and providing strategies along with a four-step process that practitioners can use to manage complexity.
Date: August 2020
Creator: Adana, Saban
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Multifactorial Determinants of Change in Mental Disorder and Happiness among Older Americans

Mental health is an intrinsic capability that constitute an essential component of healthy aging. Mental health is constituted by positive constructs such as happiness and negative constructs (mental disorders) such as depression. As people grow older, they become more prone to developing mental disorders which are linked to poorer quality of life, increased disability, increased utilization and cost of health services, and higher rates of suicide. This dissertation involved three studies that focused on factors that predict change in mental disorders and happiness of older Americans over a period of five years. Two waves of publicly available national representative data from the National Social Life Health and Aging Project (NSHAP) collected in 2010 and 2015 were used. A total of 2210 older adults within the ages 62-90 years were used in the analyses. Mental health measures were CES-Depression scale, HADS anxiety scale, and self-rated happiness. Essay 1 aimed to identify the important aspects of older adults' interaction with their neighborhood that predict the presence of mental disorder and happiness. Essay 2 evaluated the psychosocial factors that predict change in mental disorder and happiness of older adults, whereas essay 3 investigated the multifactorial determinants of change in mental disorder and happiness …
Date: August 2020
Creator: Adaralegbe, Adeleye Ayinde
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Exploring the Impact of Adverse Childhood Experiences on Resilience, School Engagement and Success in Adolescents with Co-Occurring Autism Spectrum Disorder and Attention Deficit Hyperactive Disorder

There remains a dearth of literature that explains with no ambiguity, the complex relationships that exist between adverse childhood experiences (ACEs) and resilience, as well as school engagement and school in individuals with a co-occurring diagnosis of autism spectrum disorder (ASD) and attention deficit hyperactive disorder (ADHD). This study seeks to fill this missing gap in the literature. These research questions were answered using a retrospective cross-sectional study design of national secondary data from the National Survey of Children's Health (NSCH). The findings revealed that the more ACEs an individual had, the less they were likely to engage and succeed in school. A similar finding was obtained for resilience as individuals with more ACEs showed less resilience. However, counterintuitively to the hypothesis of the project, having both ASD and ADHD does not necessarily make these outcomes worse compared to having a singular diagnosis of either ASD or ADHD. The significance of this study is that it informs rehabilitation counselors as well as educators on the need for early identification of individuals with ASD and ADHD with a background of ACEs and commence interventions early enough to ensure they are more resilient and obtain improved success in school-related activities as well …
Date: August 2021
Creator: Adaralegbe, Ngozi Jane Frances
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Improving Memory Performance for Both High Performance Computing and Embedded/Edge Computing Systems (open access)

Improving Memory Performance for Both High Performance Computing and Embedded/Edge Computing Systems

CPU-memory bottleneck is a widely recognized problem. It is known that majority of high performance computing (HPC) database systems are configured with large memories and dedicated to process specific workloads like weather prediction, molecular dynamic simulations etc. My research on optimal address mapping improves the memory performance by increasing the channel and bank level parallelism. In an another research direction, I proposed and evaluated adaptive page migration techniques that obviates the need for offline analysis of an application to determine page migration strategies. Furthermore, I explored different migration strategies like reverse migration, sub page migration that I found to be beneficial depending on the application behavior. Ideally, page migration strategies redirect the demand memory traffic to faster memory to improve the memory performance. In my third contribution, I worked and evaluated a memory-side accelerator to assist the main computational core in locating the non-zero elements of a sparse matrix that are typically used in scientific, machine learning workloads on a low-power embedded system configuration. Thus my contributions narrow the speed-gap by improving the latency and/or bandwidth between CPU and memory.
Date: December 2021
Creator: Adavally, Shashank
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Queering Afrofuturism: Freedom Dreaming and Co-Constructing Black Queer Spaces in Teacher Preparation Programs

Using queer and Afrofuturist frameworks, this Black feminist qualitative study explored queer Black pre-and in-service teachers' cultural and intersectional practices as they navigated traditional heteronormative educational spaces. This research study relied on counternarratives and storytelling and drew from Afrofuturism to understand the use of their lived experiences to counter monolithic queer narratives. The queer Black teachers in this study examined and negotiated how their Blackness and queerness showed up in teacher preparation programs (TPP) and K-12 classrooms. Moreover, they eventually refused to hide or censure their authentic selves. An analysis of the narratives and counternarratives showed that queer Black teachers drew from ancestral traditions to create queer Afrofuturist spaces in TPPs and educational places. Furthermore, due to their queer Black intersectional approaches, their classrooms, assignments, curriculum, and pedagogy disrupted normative teaching practices. Implications, recommendations, and future research are discussed.
Date: July 2023
Creator: Adeniji, Danelle Althea
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Magnetron Sputtering of Transition Metal Oxynitrides and Their Characterization with Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy (open access)

Magnetron Sputtering of Transition Metal Oxynitrides and Their Characterization with Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy

Transition metal oxynitrides are of growing interest for their use as electrocatalyst for nitrogen reduction reaction. The metals in the oxynitride used for catalytic process are stabilized in intermediate state for effective activation of nitrogen. Therefore, studying the interaction of metal oxynitrides films to ambient exposure is necessary. Here, sputter deposited vanadium oxynitride is compared to cobalt oxynitride using insitu Auger electron spectroscopy (AES), ex situ X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). After deposition in Ar/N2 environment, in situ AES spectra indicate that film is vanadium oxynitride despite oxygen is not the reactive gas. In contrast, in situ AES indicate film is pure cobalt nitride at the same base pressure and deposition condition (as vanadium). For ambient exposure, in situ AES indicate the incorporation of oxygen in the cobalt nitride film to form cobalt oxynitride. Ex situ XPS indicate both films get more oxidized but uniformly distributed as there is only slight difference in grazing and normal emission XPS. XRD and SEM also indicate how homogeneously distributed both films are. These finding confirms how important it is that transition metal centers are kept in intermediate oxidation state for the activation of nitrogen bond.
Date: May 2023
Creator: Adesope, Qasim Adewale
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Role of Eigenvalues of Parity Check Matrix in Low-Density Parity Check Codes (open access)

The Role of Eigenvalues of Parity Check Matrix in Low-Density Parity Check Codes

The new developments in coding theory research have revolutionized the application of coding to practical systems. Low-Density Parity Check (LDPC) codes form a class of Shannon limit approaching codes opted for digital communication systems that require high reliability. This thesis investigates the underlying relationship between the spectral properties of the parity check matrix and LDPC decoding convergence. The bit error rate of an LDPC code is plotted for the parity check matrix that has different Second Smallest Eigenvalue Modulus (SSEM) of its corresponding Laplacian matrix. It is found that for a given (n,k) LDPC code, large SSEM has better error floor performance than low SSEM. The value of SSEM decreases as the sparseness in a parity-check matrix is increased. It was also found from the simulation that long LDPC codes have better error floor performance than short codes. This thesis outlines an approach to analyze LDPC decoding based on the eigenvalue analysis of the corresponding parity check matrix.
Date: August 2020
Creator: Adhikari, Dikshya
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Aerial Photograph of Sam Houston Statue, 'A Tribute to Courage'

A statue or Sam Houston entitled, 'A Tribute to Courage' on the northbound side of I-45 in Huntsville, TX.
Date: July 6, 2021
Creator: Adickes, David
Object Type: Photograph
System: The Portal to Texas History

Aerial Photograph of Sam Houston Statue, 'A Tribute to Courage'

A statue or Sam Houston entitled, 'A Tribute to Courage' on the northbound side of I-45 in Huntsville, TX.
Date: July 6, 2021
Creator: Adickes, David
Object Type: Photograph
System: The Portal to Texas History

Aerial Photograph of Sam Houston Statue, 'A Tribute to Courage'

A statue or Sam Houston entitled, 'A Tribute to Courage' on the northbound side of I-45 in Huntsville, TX.
Date: July 6, 2021
Creator: Adickes, David
Object Type: Photograph
System: The Portal to Texas History
Aerial Video Footage of Sam Houston Statue, 'A Tribute to Courage' captions transcript

Aerial Video Footage of Sam Houston Statue, 'A Tribute to Courage'

A statue or Sam Houston entitled, 'A Tribute to Courage' on the northbound side of I-45 in Huntsville, TX. Video footage is silent.
Date: July 6, 2021
Creator: Adickes, David
Object Type: Video
System: The Portal to Texas History

Option Pricing Under New Classes of Jump-Diffusion Processes

In this dissertation, we introduce novel exponential jump-diffusion models for pricing options. Firstly, the normal convolution gamma mixture jump-diffusion model is presented. This model generalizes Merton's jump-diffusion and Kou's double exponential jump-diffusion. We show that the normal convolution gamma mixture jump-diffusion model captures some economically important features of the asset price, and that it exhibits heavier tails than both Merton jump-diffusion and double exponential jump-diffusion models. Secondly, the normal convolution double gamma jump-diffusion model for pricing options is presented. We show that under certain configurations of both the normal convolution gamma mixture and the normal convolution double gamma jump-diffusion models, the latter exhibits a heavier left or right tail than the former. For both models, the maximum likelihood procedure for estimating the model parameters under the physical measure is fairly straightforward; moreover, the likelihood function is given in closed form thereby eliminating the need to embed a probability density function recovery procedure such as the fast Fourier transform or the Fourier-cosine expansion methods in the parameter estimation procedure. In addition, both models can reproduce the implied volatility surface observed in the options data and provide a good fit to the market-quoted European option prices.
Date: December 2023
Creator: Adiele, Ugochukwu Oliver
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Identification, Characterization and Engineering of UDP-Glucuronosyltransferases for Synthesis of Flavonoid Glucuronides

Flavonoids are polyphenolics compounds that constitute a major group of plant specialized metabolites, biosynthesized via the phenylpropanoid/polymalonate pathways. The resulting specialized metabolites can be due to decoration of flavonoid compounds with sugars, usually glucose, by the action of regiospecific UDP-glycosyltransferase (UGT) enzymes. In some cases, glycosylation can involve enzymatic attachment of other sugar moieties, such as glucuronic acid, galactose, rhamnose or arabinose. These modifications facilitate or impact the bioactivity, stability, solubility, bioavailability and taste of the resulting flavonoid metabolites. The present work shows the limitations of utilizing mammalian UDP-glucuronosyltransferases (UGATs) for flavonoid glucuronidation, and then proceeds to investigate plant UG(A)T candidates from the model legume Medicago truncatula for glucuronidating brain-targeted flavonoid metabolites that have shown potential in neurological protection. We identified and characterized several UG(A)T candidates from M. truncatula which efficiently glycosylate various flavonoids compounds with different/multiple regiospecificities. Biochemical characterization identified one enzyme, UGT84F9, that efficiently glucuronidates a range of flavonoid compounds in vitro. In addition, examination of the ugt84f9 gene knock-out mutation in M. truncatula indicates that UGT84F9 is the major UG(A)T enzyme that is necessary and sufficient for attaching glucuronic acid to flavonoid aglycones, particularly flavones, in this species. Finally, the identified UG(A)T candidates were analyzed via homology …
Date: December 2020
Creator: Adiji, Olubu Adeoye
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Traffic-Generated Air Pollution-Exposure Mediated Expression of Factors Associated with Progression of Multiple Sclerosis in a Female Polipoprotein E Knockout Mouse Model

Environmental air pollution is one risk factor associated with the onset and progression of multiple sclerosis (MS). In this project, we investigated the effects of ubiquitous traffic-generated pollutants, namely a mixture of gasoline and diesel vehicle exhaust (MVE), on signaling pathways associated with the pathophysiology of MS in the central nervous system (CNS) of either ovary intact (ov+) or ovariectomized (ov-) female Apolipoprotein (Apo) E-/-. Specifically, we investigated whether a subchronic inhalation exposure to MVE (200 PM μg/m3; 6 hr/d, 7d/wk, 30d) vs. filtered air (FA) controls altered myelination, T cell infiltration, blood-brain barrier (BBB) integrity, or production of reactive oxygen species (ROS) and expression of neuroinflammation markers in the CNS ov+ and ov- Apo E-/- mice. Our results revealed that inhalation exposure to MVE resulted in increased demyelination and CD4+ and CD8+ T cell infiltration, associated with alterations in BBB integrity. Disruption of the BBB was evidenced by decreased tight junction (TJ) protein expression, increased matrix metalloproteinase (MMPs) activity, and increased permeability of immunoglobin (Ig) G, which were more pronounced in the MVE ov- group. Moreover, MVE-exposure also promoted ROS and neuroinflammatory signaling in the CNS of ov+ and ov- mice, compared to FA groups. To analyze mechanisms that …
Date: December 2020
Creator: Adivi, Anna
Object Type: Thesis or Dissertation
System: The UNT Digital Library