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A Genetic Approach to Identify Proteins that Interact with Eukaryotic Microtubule Severing Proteins via a Yeast Two Hybrid System

Description: Microtubules (MT) are regulated by multiple categories of proteins, including proteins responsible for severing MTs that are therefore called MT-severing proteins. Studies of katanin, spastin, and fidgetin in animal systems have clarified that these proteins are MT-severing. However, studies in plants have been limited to katanin p60, and little is known about spastin or fidgetin and their function in plants. I looked at plant genomes to identify MT-severing protein homologues to clarify which severing proteins exist in plants. I obtained data from a variety of eukaryotic species to look for MT-severing proteins using homology to human proteins and analyzed these protein sequences to obtain information on the evolution of MT-severing proteins in different species. I focused this analysis on MT-severing proteins in the maize and Arabidopsis thaliana genomes. I created evolutionary phylogenetic trees for katanin-p60, katanin-p80, spastin, and fidgetin using sequences from animal, plant, and fungal genomes. I focused on Arabidopsis spastin and worked to understand its functionality by identifying protein interaction partners. The yeast two-hybrid technique was used to screen an Arabidopsis cDNA library to identify putative spastin interactors. I sought to confirm the putative protein interactions by using molecular tools for protein localization such as the YFP system. Finally, a Biomolecular Fluorescence Complementation (BiFC) assay was initiated as a proof of concept for confirmation of in vivo protein-protein interaction.
Date: May 2020
Creator: Alhassan, Hassan H
Partner: UNT Libraries

Privacy Preserving Machine Learning as a Service

Description: Machine learning algorithms based on neural networks have achieved remarkable results and are being extensively used in different domains. However, the machine learning algorithms requires access to raw data which is often privacy sensitive. To address this issue, we develop new techniques to provide solutions for running deep neural networks over encrypted data. In this paper, we develop new techniques to adopt deep neural networks within the practical limitation of current homomorphic encryption schemes. We focus on training and classification of the well-known neural networks and convolutional neural networks. First, we design methods for approximation of the activation functions commonly used in CNNs (i.e. ReLU, Sigmoid, and Tanh) with low degree polynomials which is essential for efficient homomorphic encryption schemes. Then, we train neural networks with the approximation polynomials instead of original activation functions and analyze the performance of the models. Finally, we implement neural networks and convolutional neural networks over encrypted data and measure performance of the models.
Date: May 2020
Creator: Hesamifard, Ehsan
Partner: UNT Libraries

Self-Reported Feelings of Shame and Fear of Failure among High Ability Undergraduates

Description: Understanding how emotions influence motivation among students is critical to the talent development process. Research shows that certain emotions elicit an approach motive while other emotions elicit an avoidance motive. This study explored emotional disposition and fear of failure among undergraduates enrolled in honors college (n = 63) compared to undergraduates enrolled in regular college courses (n = 296). Results suggest that dispositional shame is positively correlated with fear of failure; however, neither gender nor enrollment in honors college predict fear of failure beyond dispositional shame. Students enrolled in honors college do not differ on measurements of shame and fear of failure compared to students not enrolled in honors college. In general, female undergraduates were more likely to report experiences of shame, guilt, fear of shame and embarrassment, and fear of devaluing one's self-estimate than their male peers. The findings are discussed in light of a need to understand high-ability college students.
Date: May 2020
Creator: Nyikos, Tara
Partner: UNT Libraries

Effective Leadership Practices in Improvement-Required Schools

Description: This mixed-methods study identified the effective practices of the principal and leadership team in an Improvement-Required (IR) high school that significantly influenced student achievement and guided their school from IR to a rating of Met Standard in one year. IR or F schools under the new system are schools that failed to meet the state accountability target goals. The high school in this study had a large culturally and economically diverse student population with a high percentage of English learners. The leadership practices were identified through four themes revealed by the qualitative data analysis of focus group and individual in-depth interviews: (a) importance of instructional, collaborative leadership, (b) intentional planning of effective instruction for all students, (c) consistent use of data to guide instruction, and (d) ongoing, data based, targeted staff development. The study findings are significant due to strong corroboration between the qualitative data collected from the interviews and the quantitative results from the faculty survey.
Date: May 2020
Creator: Kimm, Linda L.
Partner: UNT Libraries

Entrepreneurial Orientation: An Interdisciplinary Approach to Public Entrepreneurship in Saudi Arabia

Description: The increasing demands of efficiency and effectiveness in the public sector encourage political leaders and policy makers to adopt and apply advanced techniques and solutions to overcome flaws in public organizational performance. Entrepreneurship was introduced in several Western countries as a way to improve their processes and management through adopting private sector management principles and market-oriented techniques. In 2015, Saudi Arabia announced its 2030 vision, which introduced hundreds of innovative and creative initiatives aiming to overcome issues of the turbulent environment, future oil depletion, budgetary pressures, and public demands for efficiency and effectiveness. Building on interdisciplinary perspectives, this study investigates entrepreneurial orientation among Saudi public employees from all administrative regions across the country. Building on McClelland's theory of motivation, this study hypothesizes that the motives of need for achievement, need for affiliation, and need for power are positively associated with entrepreneurial behavior. It also hypothesizes that excessive organizational hierarchy, formalization, and lack of autonomy constrain employees' entrepreneurial activities. Moreover, this study adopts a sociological perspective in proposing solutions for facilitating entrepreneurial orientation among public employees by hypothesizing that human and social capital promote an entrepreneurial orientation. Multiple regression analysis reveals that Saudi public employees with a higher level of need for achievement and need for power tend to be more entrepreneurial, while need for affiliation fails to predict entrepreneurial orientation. Furthermore, the findings suggest that a high level of hierarchy and formalization in public organizations is negatively associated to entrepreneurial orientation, while a high level of autonomy is positively associated with entrepreneurial orientation. Finally, the study finds that employees with a high level of breadth and depth of experience (human capital) are more likely to be entrepreneurial, while a high level of bonding social capital and bridging social capital promote a negative and a positive entrepreneurial orientation, respectively.
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Date: May 2020
Creator: Alzomia, Abdullah
Partner: UNT Libraries

A Mixed Method Inquiry into Student Academic Optimism: Validation of the Construct and Its Use to Give Voice to Latinx Student Experiences

Description: This study examined student academic optimism in four diverse North Texas school districts. This study used a convergent parallel mixed methods design to analyze results of an online administration of the survey, and Latinx student responses to a focus group protocol derived from the survey. Quantitative results indicate the individual scales making up the construct align with previous research results. The three scales were found to be strongly and significantly correlated, indicating the potential for validation. Qualitative results indicate Latinx students' perceptions of their academic careers align with four themes. Latinx students are keenly aware of their teachers as a person, their school as a community, the intrusion of the outside world, and students as agents. Qualitative results support the importance of the three components of the construct, student trust in teachers, student academic press, and student identification with school. As a new source of data, combined with existing metrics of instructional effectiveness, student academic optimism could increase the ability of decision makers to improve the overall efficacy of school systems especially when addressing the persistent opportunity gaps for Latinx and other students of color.
Date: May 2020
Creator: Viamontes Quintero, Jesika
Partner: UNT Libraries

Public Order and Social Control through Religion in the Roman Republic

Description: Rome was among the largest cities in Europe during the Republic era, with a population that was diverse in social status and ethnicity. To maintain public order and social control of such a large, continually growing and shifting population that encompassed mixed cultures and Roman citizens, the Roman elites had to use various methods to keep the peace and maintain social stability. As religion was so deeply ingrained into every aspect of Roman life, it is worth taking a deeper look into how those in charge used it to maintain peace and relative control in Rome and its territories. Chapter 1 offers a brief look at the history of Roman religion, its terms and definitions, and the idea of social control as it pertains to this thesis. Chapter 2 shows the motivations of the Roman elite classes in their use of religion to maintain public order and enforce social control of the mass population. Couched in the need to uphold the Pax Deorum or Peace of the Gods, religious piety and order was cultivated as a means to protect the Republic from harm. Chapter 3 explains how the Patrician and Plebeian classes directed the attention of the residents of Rome with a calendar that was filled with rituals, sacrifices, festivals, and market days. In keeping a busy religious schedule, the people of Rome maintained a constant and direct relationship with the gods. Chapter 4 discusses the importance of women in the roles of priestesses and officers in religious cult to sustain the religious health and welfare of the city of Rome and the smaller communities within the city they inhabited. Chapter 5 examines the use of execution as a religious means of enforcing public order and social control. The chapter explores different means of execution and how they were placed ...
Date: May 2020
Creator: Williams, Sheri
Partner: UNT Libraries

Computational Study of Intermolecular Interactions in Complex Chemical Systems

Description: This work discusses applications of computational simulations to a wide variety of chemical systems, to investigate intermolecular interactions to develop force field parameters and gain new insights into chemical reactivity and structure stability. First, we cover the characterization of hydrogen-bonding interactions in pyrazine tetracarboxamide complexes employing quantum topological analyses. Second we describe the use of quantum mechanical energy decomposition analysis (EDA) and non-covalent interactions (NCIs) analysis to investigate hydrogen-bonding and intermolecular interactions in a series of representative 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) ion pairs extracted from classical equilibrium and non-equilibrium molecular dynamics simulations. Thirdly, we describe the use of multipolar/polarizable AMOEBA force field to study the extraction of benzene from a gasoline model employing 1,3-dimethylimidazolium tetrafluorobrorate, [DMIM][BF4], and ethylmethylimidazolium tetrafluorobrorate, [EMIM][BF4]. Fourthly, we cover the recent improvements and new capabilities of the QM/MM code "LICHEM". Finally, we describe the use of polarizable ab initio QM/MM calculations and study the reaction mechanism of N-tert-butyloxycarbonylation of aniline in [EMIm][BF4], and ground state destabilization in uracil DNA glycosylase (UDG).
Date: May 2020
Creator: Vazquez Montelongo, Erik Antonio
Partner: UNT Libraries

Women in Wrestling Arenas: How Globalization, Socially Produced Spaces, and Commodification Impact their Portrayal and Empowerment Post Women's Revolution

Description: The Women's Revolution in 2015 has led to a drastic shift in the ways women are portrayed in professional wrestling. The Women's Revolution came as a result of the social unrest over the lack of time women were receiving on the televised shows. Where women's storylines had centered on their sexuality, they are now presented as equal to their male counterparts after the Women's Revolution. Through an exploration of concepts in globalization, commodification, and socially produced spaces, this research seeks to understand and contextualize the Women's Revolution, the degree to which the portrayed women's equality has been achieved, and the resulting impacts of the female superstars overall. I argue that that this "equality" has been achieved through inscribing the traditionally masculine qualities of wrestling to women, has resulted in an unequal distribution of opportunities to particular female superstars rather than equality for all women on the shows, and that phallocentric objectification of the female superstars still occurs in certain aspects of professional wrestling.
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Date: May 2020
Creator: Kohlmeyer, Collin
Partner: UNT Libraries

Corporate Social Responsibility and Brand Equity: Insights to Global, Luxury, and Co-Creation Brand Building Strategies

Description: Given the growing number of socially conscious and ethical consumers, brands have been taking a strategic approach to corporate social responsibility (CSR) by integrating socially responsible activities into the brand's core value proposition in order to remain relevant in the marketplace and drive brand equity. Extant research on CSR has investigated its effect on various consumer behavior outcomes. However, from a brand-building perspective, there is still a lack of understanding on how to effectively leverage CSR, and not enough directions on how to overcome its challenges in order to build brand equity. Therefore, through three essays, the objective of this dissertation is to provide a deep understanding of the effect that CSR has on brand equity while revealing brand-building strategies that can be implemented to effectively leverage CSR, specifically within the (1) global, (2) luxury, and (3) co-creation contexts.
Date: May 2020
Creator: Muniz, Fernanda
Partner: UNT Libraries

The Administration of Unemployment Relief by the State of Texas during the Great Depression, 1929-1941

Description: During the Great Depression, for the first time in its history, the federal government provided relief to the unemployed and destitute through myriad New Deal agencies. This dissertation examines how "general relief" (direct or "make-work") from federal programs—primarily the Emergency Relief and Construction Act (ERCA) and Federal Emergency Relief Administration (FERA)—was acquired and administered by the government of Texas through state administrative agencies. These agencies included the Chambers of Commerce (1932-1933), Unofficial Texas Relief Commission (1933), Texas Rehabilitation and Relief Commission (1933), Official Texas Relief Commission (1933-1934), Texas Relief Commission Division of the State Board of Control (1934), and the Department of Public Welfare (1939). Overall, the effective administration of general relief in the Lone Star State was undermined by a political ideology that persisted from, and was embodied by, the "Redeemer" Constitution of 1876.
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Date: May 2020
Creator: Park, David B
Partner: UNT Libraries

The Ecological Importance and Population Structure of Magellanic Woodpeckers (Campephilus magellanicus) in the World's Southernmost Forests

Description: The Magellanic woodpecker (Campephilus magellanicus), the largest woodpecker in Central and South America, is declining throughout its range. Notably, limited research has been conducted on the Campephilus genus, especially for island populations. Mostly during austral summers 2015-2017, I explored the ecological importance and population structure of Magellanic woodpeckers on Navarino Island, Chile (55°04′S, 67°40′W). First, I assessed how coleopteran larval density and distribution within trees may influence Magellanic woodpecker foraging behavior. Second, I designed an experiment to determine which of three detection methods would best elicit a woodpecker detection. Third, I conducted a population genetics study to elucidate trends within and among Magellanic woodpecker populations to better inform management decisions. I identified two coleopteran species: one lucanid (Erichius femoralis) and one cerambycid (Microplophorus magellanicus) within two lenga (Nothofagus pumilio) trees foraged on by Magellanic woodpeckers. Maximum woodpecker excavation depths were 71-90 mm; most larval gallery depths were 51-70 mm. The drumming device most effectively influenced the likelihood of a woodpecker detection. The odds of a woodpecker responding were 2.14 times more likely than responding to either a playback or control. On Navarino Island, I observed a pattern of isolation by distance among sampled woodpeckers, slight female sex-biased dispersal, and family groups likely consisted of nuclear families with partner replacement. Genetic diversity estimates were lower for Navarino woodpeckers than for mainland populations. Future research should build upon these results to better understand Magellanic woodpecker life history characteristics and its role in the ecosystem.
Date: May 2020
Creator: Wynia, Amy Lynn
Partner: UNT Libraries

"Digital Tap Dance": Tap Dance as Medium for Composition

Description: This dissertation investigates the process of collaboration and the application of both notational and technological schemes to integrate elements of contemporary composition and tap dance as a consolidated art form. Overall, this document gives an overview of choreographer/composer collaborations in Western classical music; movement notation; and ultimately analyzes my original music—a live set for tap dancer, live musicians and electronics—entitled Digital Tap Dance. Altogether, this project represents the culmination of music and dance as a compelling intermedia collaboration. By (1) researching different practices of composer-choreographer collaborations, (2) notating rudiments for tap dance, (3) creating software for tap dancers, and (4) composing original music for tap dancers, this dissertation will create options for composers and choreographers alike in composition and improvisation.
Date: May 2020
Creator: Thiede, Jacob Ryan
Partner: UNT Libraries

Discourse Indicative of Computational Thinking within a Virtual Community

Description: This study explores the phenomenon of computational thinking indicated by the use of Bloom's taxonomy's cognitive domain verbs in the Scratch community, the online, collaborative environment for the Scratch Visual Programming Language (VPL). A corpus of 660,984 words from three Scratch community sub-forums provide the data for this study. By semantically aligning cognitive domain verbs of Bloom's revised taxonomy to computational thinking (CT) dimensions, the occurrences of the verbs in Scratch community sub-forums are used to indicate instances of computational thinking. The methodology utilizes qualitative coding and analysis with R® and RStudio®. The findings show language attributes such as expressions of imagination, sharing of creative details, collaborative development ideas, teaching, modeling, innovating, solutions focused, and technical support to be indicative of computational thinking and CT dimensions. The computational thinking dimension referred to as computational perspectives occurs most frequently within Scratch community participant discourse. The environmental factors found to contribute to computational thinking and the CT dimensions are supporting tools, personalized learning, supportive organizational culture, social learning, and organizational support. Common among the three computational dimensions is the contributing environmental factor described as supportive organizational culture, with the computational perspectives dimension prevailing among the corpora. The characteristics of computational perspectives and supportive organizational culture suggest a desire for human connection in the attainment of technological skills and knowledge.
Date: May 2020
Creator: Woods, Charles
Partner: UNT Libraries

Institutional Pluralism and the Organization's Response: A Case Study of Chinese Women's Ice Hockey

Description: In recent years, the sport of women's ice hockey is growing fast worldwide. Upon winning the bid to host the 2022 Winter Olympics, women's ice hockey in China started to develop rapidly. However, the development of women's ice hockey in China has encountered numerous challenges. These challenges include addressing traditional Chinese culture, gender norms, and the process of sport reform. This study used a qualitative case study methodology to examine the perspectives of Chinese women ice hockey players, coaches, club administrators, government administrators, and the parents of youth hockey players to understand how women's ice hockey navigated itself within the institutional complexity to gain legitimacy, and how the different institutional logics impacted the identities of organizations within women's ice hockey in China. An abductive grounded theory approach was used to analyze the transcriptions and archived documents. Findings indicated that there were challenges for the development of women's ice hockey in China at macro level, meso level, and micro level. Actors such as hockey administrations, professional clubs, and ice hockey coaches and players at different levels adopted multiple forms of institutional work to find out ways to incorporate institutional structures that mitigated the fact that there were multiple logics. In addition, influenced by competing logics, the organizations created collective identities to balance those logics. This study provides insights into how the actors within sport organizations create a more satisfactory environment to gain legitimacy.
Date: May 2020
Creator: Li, Hongxin
Partner: UNT Libraries

Teacher Certification Program Types and Their Impact on Teacher Self-Efficacy

Description: The overarching purpose of the study was specifically designed to examine how teacher preparation programs contributed to novice teachers' sense of self-efficacy. The significance of this study related to how well teachers were prepared, based upon their preparation program. This qualitative methods study incorporated a research design consisting of phenomenological research. Eleven thematic findings derived based upon the participants' input after several series of data analysis and reduction, using a general deductive approach. Results showed many implications of how teacher preparation programs contributed to the participants' sense of self-efficacy. Major implications for teacher preparation programs and their impact on novice teachers are discussed, such as improvement measures for preparation programs, and opportunities to increase teacher effectiveness.
Date: May 2020
Creator: Muhammad, Gerald
Partner: UNT Libraries

Gamification to Solve a Mapping Problem in Electrical Engineering

Description: Coarse-Grained Reconfigurable Architectures (CGRAs) are promising in developing high performance low-power portable applications. In this research, we crowdsource a mapping problem using gamification to harnass human intelligence. A scientific puzzle game, Untangled, was developed to solve a mapping problem by encapsulating architectural characteristics. The primary motive of this research is to draw insights from the mapping solutions of players who possess innate abilities like decision-making, creative problem-solving, recognizing patterns, and learning from experience. In this dissertation, an extensive analysis was conducted to investigate how players' computational skills help to solve an open-ended problem with different constraints. From this analysis, we discovered a few common strategies among players, and subsequently, a library of dictionaries containing identified patterns from players' solutions was developed. The findings help to propose a better version of the game that incorporates these techniques recognized from the experience of players. In the future, an updated version of the game that can be developed may help low-performance players to provide better solutions for a mapping problem. Eventually, these solutions may help to develop efficient mapping algorithms, In addition, this research can be an exemplar for future researchers who want to crowdsource such electrical engineering problems and this approach can also be applied to other domains.
Date: May 2020
Creator: Balavendran Joseph, Rani Deepika
Partner: UNT Libraries

Ayurveda as Medicine

Description: Complimentary and alternate medicine, especially Ayurveda is gaining popularity in United States. However, there are various barriers that people face in adopting Ayurvedic practices into their lives and making cultural, familial and societal changes to better their health. This research explores these relationships and barriers behind why some people adopt and are able/unable to sustain Ayurvedic practices in the presence of traditional bio-medicine.
Date: May 2020
Creator: Das, Minakshi
Partner: UNT Libraries

A Conductor's Guide to the Choral Music of Joshua Rist

Description: Composed exclusively in the last decade, Joshua Rist's works have received significant performances by numerous high-profile ensembles including prominent high school, collegiate, and community choirs. Although conductors continue to program his works with increased frequency, minimal scholarly work is published about this music and its composer. The quality of Rist's body of work coupled with a scarcity of scholarly research provides opportunity for further study. Closer examination of Rist's works could provide a framework for conductors who perform his music. This study provides background and bibliographic information on the composer. It contains a review of choral works by Rist highlighting critical elements within each work that provide a framework for future performances of his works. This dissertation identifies stylistic characteristics that define Rist's compositional style. Additionally, it highlights the evolution of Rist's artistic growth and development.
Date: May 2020
Creator: Brown, Joshua Ray
Partner: UNT Libraries

Atomic Layer Deposition of H-BN(0001) on Transition Metal Substrates, and In Situ XPS Study of Carbonate Removal from Lithium Garnet Surfaces

Description: The direct epitaxial growth of multilayer BN by atomic layer deposition is of critical significance forfo two-dimensional device applications. X-ray photoelectron spectroscopy (XPS) and low energy electron diffraction (LEED) demonstrate layer-by-layer BN epitaxy on two different substrates. One substrate was a monolayer of RuO2(110) formed on a Ru(0001) substrate, the other was an atomically clean Ni(111) single crystal. Growth was accomplished atomic layer deposition (ALD) cycles of BCl3/NH3 at 600 K substrate temperature and subsequent annealing in ultrahigh vacuum (UHV). This yielded stoichiometric BN layers, and an average BN film thickness linearly proportional to the number of BCl3/NH3 cycles. The BN(0001)/RuO2(110) interface had negligible charge transfer or band bending as indicated by XPS and LEED data indicate a 30° rotation between the coincident BN and oxide lattices. The atomic layer epitaxy of BN on an oxide surface suggests new routes to the direct growth and integration of graphene and BN with industrially important substrates, including Si(100). XPS and LEED indicated epitaxial deposition of h-BN(0001) on the Ni(111) single crystal by ALD, and subsequent epitaxially aligned graphene was deposited by chemical vapor deposition (CVD) of ethylene at 1000 K. Direct multilayer, in situ growth of h-BN on magnetic substrates such as Ni is important for spintronic device applications. Solid-state electrolytes (SSEs) are of significant interest for their promise as lithium-ion conducting materials but are prone to degradation due to lithium carbonate formation on the surface upon exposure to atmosphere, adversely impacting Li ion conduction. In situ XPS monitored changes in the composition of the SSE Li garnet (Li6.5La3Zr1.5Ta0.5O12, LLZTaO) upon annealing in UHV and upon Ar+ ion sputtering. Trends in core level spectra demonstrate that binding energy (BE) calibration of the Li 1s at 56.4 eV, yields a more consistent interpretation of results than the more commonly used standard of the ...
Date: May 2020
Creator: Jones, Jessica C.
Partner: UNT Libraries

Epileptic Seizure Detection and Control in the Internet of Medical Things (IoMT) Framework

Description: Epilepsy affects up to 1% of the world's population and approximately 2.5 million people in the United States. A considerable portion (30%) of epilepsy patients are refractory to antiepileptic drugs (AEDs), and surgery can not be an effective candidate if the focus of the seizure is on the eloquent cortex. To overcome the problems with existing solutions, a notable portion of biomedical research is focused on developing an implantable or wearable system for automated seizure detection and control. Seizure detection algorithms based on signal rejection algorithms (SRA), deep neural networks (DNN), and neighborhood component analysis (NCA) have been proposed in the IoMT framework. The algorithms proposed in this work have been validated with both scalp and intracranial electroencephalography (EEG, icEEG), and demonstrate high classification accuracy, sensitivity, and specificity. The occurrence of seizure can be controlled by direct drug injection into the epileptogenic zone, which enhances the efficacy of the AEDs. Piezoelectric and electromagnetic micropumps have been explored for the use of a drug delivery unit, as they provide accurate drug flow and reduce power consumption. The reduction in power consumption as a result of minimal circuitry employed by the drug delivery system is making it suitable for practical biomedical applications. The IoMT inclusion enables remote health activity monitoring, remote data sharing, and access, which advances the current healthcare modality for epilepsy considerably.
Date: May 2020
Creator: Sayeed, Md Abu
Partner: UNT Libraries

Donor-Acceptor Systems: Photochemistry and Energy Harvesting Applications

Description: Donor-acceptor systems have unique properties that make them ideal candidates for solar energy harvesting through mimicry of natural photosynthesis. This dissertation is focused on unraveling those unique properties in various types of donor-acceptor systems. The systems investigated are categorized as closely linked, push-pull, supramolecular, and multi-unit. As part of the study, photosynthetic analogues based on BF2-chelated dipyrromethene (BODIPY), porphyrin, phthalocyanine, truxene, ferrocene, quinone, phenothiazine (PTZ), perylenediimide (PDI), fullerene (C60), dicyanoquinodimethane (DCNQ), tetracyanobutadiene (TCBD), and triphenylamine (TPA) are investigated. The effects of proximity between donor-acceptor entities, their geometrical orientation relative to each other, push-pull character of substituents, and competitive energy and electron transfer are examined. In all systems, primary events of photosynthesis are observed, that is absorption and energy transfer and/or electron transfer is witnessed. Ultrafast transient absorption spectroscopy is utilized to characterize the photo-induced events, while other methods such as steady-state luminescence, cyclic voltammetry, differential pulse voltammetry, chronoamperometry, and computational calculations are used to aid in the characterization of the donor-acceptor systems, in particular their applicability as solar energy harvesters.
Date: May 2020
Creator: Thomas, Michael Brandon
Partner: UNT Libraries

Unpacking Asylum: Participatory Online Platforms in the Information-Seeking Phase

Description: In the last few years, the world has been gripped by a crisis of forced migration and displaced persons. Being forced migrants, asylum-seekers are a unique and diverse population, originating from many countries with different backgrounds and experiences. This makes fulfilling the information needs of the asylum community difficult. Online participatory platforms, such as blogs and discussion forums, are flexible, adaptive information resources that could be used to meet the diverse needs of this population. In this study, I compare two online resources used by asylum-seekers, a blog and discussion forum, using social network analysis and topic modeling techniques. Through these analyses, I have determined the conversational archetype the best reflects both websites and discovered the information needs expressed and, in many cases, resolved through conversations in these online spaces. The core finding of this study is that providing direct access to an expert, such as through an interactive blog, promotes dialogue on a greater variety of topics and increases the likelihood of a thorough response. Furthermore, blog posts may inform participants' comments by providing them with the necessary vocabulary to participate fully in the online setting.
Date: May 2020
Creator: Hudson, Cassie
Partner: UNT Libraries

Interference Alignment through Propagation Delay

Description: With the rapid development of wireless communication technology, the demands for higher communication rates are increasing. Higher communication rate corresponds to higher DoF. Interference alignment, which is an emerging interference management technique, is able to substantially increase the DoF of wireless communication systems. This thesis mainly studies the delay-based interference alignment technique. The key problem lies in the design of the transmission scheme and the appropriate allocation of the propagation delay, so as to achieve the desired DoF of different wireless networks. In addition, through delay-based interference alignment, the achievability of extreme points of the DoF region of different wireless networks can be proved.
Date: May 2020
Creator: Liu, Zhonghao
Partner: UNT Libraries