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The Abraham Solvation Model Used for Prediction of Solvent-Solute Interactions and New Methods for Updating Parameters

Description: The Abraham solvation model (ABSM) is an experimentally derived predictive model used to help predict various solute properties. This work covers various uses for the ABSM including predicting molar enthalpies of vaporization, predicting solvent coefficients for two new solvents (2,2,5,5-tetramethyloxolane and diethyl carbonate), predicting values for multiple new ionic liquids (ILs). This work also introduces a novel method for updating IL ABSM parameters by updating cation- and anion-specific values using linear algebra and binary matrices.
Date: May 2021
Creator: Churchill, Brittani N
Partner: UNT Libraries

Accommodating People Safety Curriculum for Deaf and Hard of Hearing Students

Description: Children with disabilities are three to four times more likely to be abused than their non-disabled peers due to the impact of challenges related to behavior, cognition, language, social skills, and communication skills. In September of 2018, the Council for Exceptional Children (CEC) specifically noted the need to establish maltreatment prevention and response curricula and promote research and advocacy surrounding maltreatment of children with disabilities. One common curriculum recommended is Kidpower®. While Kidpower® shows promise in increasing people safety skills and offers some basic accommodations for use with disabled populations, a complete accommodation plan for deaf or hard of hearing students has not been developed. The purpose of this study was to explore how Kidpower® curriculum could be accommodated to meet the unique needs of deaf and hard of hearing students from the perspective of the deaf education community, including deaf adults, deaf education teachers, deaf education teacher preparation faculty, and parents with deaf or hard of hearing children. A combination of focus groups and interviews were utilized to review lessons and homework from the Kidpower® curriculum. Participants gave feedback on obstacles and ideas for accommodations and modifications that would mediate the challenges. Data were inductively coded and analyzed for themes. Findings indicated the deaf education community believes the curriculum needs media components, language modifications and teaching strategies, enhanced visual information, and representation of people and situations related to the lives of deaf and hard of hearing children to be an effective curriculum for this population.
This item is restricted from view until June 1, 2023.
Date: May 2021
Creator: Johnson, Jennifer A. L.
Partner: UNT Libraries
open access

Activating Artistry: Community Engagement Resources and Teaching Artist Strategies for the Bassoonist

Description: This document examines current practices and opportunities in the music performance field related to artistic citizenship, community engagement, and the field of teaching artistry. The relationship of musicians to their audiences and communities has shifted significantly in the twenty-first century, and there is an increasing need to redefine the essential skills of the professional musician. Derived from the field of teaching artistry, the concept of "activating artistry" suggests that our greatest strength and power as artists lies in drawing out individual artistic expression in other people, and it is with this power that artists as a workforce can create meaningful change in society. This intention could be manifested in many different contexts during the course of a given music career, however, developing the tool kit necessary for engaging in such work is not widely emphasized in the training of musicians. What tools can be provided for students and professionals to help them navigate both traditional and evolving career paths in music? How are bassoonists doing as a field in addressing the imperative of community engagement and artistic citizenship? How might we explore more collaborative ways to engage with our diverse communities – ways that value their perspectives? These questions guide an exploration of current practices in the bassoon field, with an overall goal of providing practical examples, resources, and inspiration for engaging in the work of activating artistry. Central to the discussion is the intersection of the professional bassoonist with the teaching artist field. Examples of lesson plans/strategies and ideas for curating educational performances demonstrate potential uses of the bassoon and its repertoire in teaching artist residencies and other community engagement settings.
Date: May 2021
Creator: Spring, Staci Alane
Partner: UNT Libraries

Alloy Design, Processing and Deformation Behavior of Metastable High Entropy Alloys

Description: This dissertation presents an assortment of research aimed at understanding the composition-dependence of deformation behavior and the response to thermomechanical processing, to enable efficient design and processing of low stacking fault energy (SFE) high entropy alloy (HEAs). The deformation behavior and SFE of four low SFE HEAs were predicted and experimentally verified using electron microscopy and in-situ neutron diffraction. A new approach of employing a minimization function to refine and improve the accuracy of a semi-empirically derived expression relating composition with SFE is demonstrated. Ultimately, by employing the minimization function, the average difference between experimental and predicted SFE was found to be 2.64 mJ m-2. Benchmarking with currently available approaches suggests that integrating minimization functions can substantially improve prediction accuracy and promote efficient HEA design with expansion of databases. Additionally, in-situ neutron diffraction was used to present the first in-situ measurement of the interspacing between stacking faults (SFs) which were correlated with work hardening behavior. Electron transparent specimens (< ~100 nm thick) were used in order to resolve nanoscale planar faults instead of the thicker sub-sized specimens (on the order of millimeters in thickness) which exhibit the classical stages III work hardening behavior characteristic of low SFE metals and alloys. The present study demonstrates these characteristic dimensions of SFs can be tracked in real-time using neutrons or high-energy x-rays. SFs have also been shown to act as barriers to dislocation motion and thus contribute to strengthening and sustained work hardening during deformation.
This item is restricted from view until June 1, 2023.
Date: May 2021
Creator: Frank, Michael
Partner: UNT Libraries
open access

An Artificial Intelligence-Driven, Model-Based Analysis of System Requirements for Exposing Off-Nominal Behaviors

Description: With the advent of autonomous systems and deep learning systems, safety pertaining to these systems has become a major concern. The existing failure analysis techniques are not enough to thoroughly analyze the safety in these systems. Moreover, because these systems are created to operate in various conditions, they are susceptible to unknown safety issues. Hence, we need mechanisms which can take into account the complexity of operational design domains, identify safety issues other than failures, and expose unknown safety issues. Moreover, existing safety analysis approaches require a lot of effort and time for analysis and do not consider machine learning (ML) safety. To address these limitations, in this dissertation, we discuss an artificial-intelligence driven model-based methodology that aids in identifying unknown safety issues and analyzing ML safety. Our methodology consists of 4 major tasks: 1) automated model generation, 2) automated analysis of component state transition model specification, 3) undesired states analysis, and 4) causal factor analysis. In our methodology we identify unknown safety issues by finding undesired combinations of components' states and environmental entities' states as well as causes resulting in these undesired combinations. In our methodology, we refer to the behaviors that occur because of undesired combinations as off-nominal behaviors (ONBs). To identify undesired combinations and ONBs that aid in exposing unknown safety issues with less effort and time we proposed various approaches for each of the task and performed corresponding empirical studies. We also discussed machine learning safety analysis from the perspective of machine learning engineers as well as system and software safety engineers. The results of studies conducted as part of our research shows that our proposed methodology helps in identifying unknown safety issues effectively. Our results also show that combinatorial methods are effective in reducing effort and time for analysis of off-nominal behaviors without overlooking any …
Date: May 2021
Creator: Madala, Kaushik
Partner: UNT Libraries
open access

At the Junction of Dissemination and Implementation: Facilitating Access to Behavior Analytic Research

Description: Research in scholarly communication is usually limited to the use and dissemination of scientific material by scholars. This excludes the transfer of knowledge from research producers to service providers. Some may argue the primary function of science is to investigate the conditions in the lab so everyday interactions with the environment are more effective and efficient. This is the underlying philosophy of the science of behavior analysis. Comprised of a basic science, an applied science and a philosophy the field of behavior analysis relies on research developments to inform effective practice. Guided by dissemination processes studied in information science, this investigation revealed the content layer in behavior analysis is primarily comprised of journal articles. Ninety four percent of the research artifacts cited in the current content layer are from journal articles. Other dissemination channels used to develop the behavior analytic content layer included scientific magazine articles, oral reports, dissertations and theses, and unpublished manuscripts. The information use environment for professionals in this field is very different than that of the scholars; most professionals do not have access to a university library. Therefore, the research producers are disseminating developments via communication channels some service providers cannot access. This investigation reveals the only dissemination channel that provides continuous access to the content layer is reaching out via informal communication; All other dissemination channels do not provide access to the entire content layer, do not provide the entire scholarly work, and/or include a barrier to access (often an associated cost). This is a concern for the field of behavior analysis as professional recommendations cannot be based on the best available evidence if the evidence is not accessible. This is a concern for the field of information science as the study of scholarly communication should not be limited to scholars alone. The process of …
Date: May 2021
Creator: Bank, Nicole L.
Partner: UNT Libraries

Benefits of Probiotics on Mortality, Growth Performance, Physiological Condition and Gut Histomophology of Juvenile Red Drum (Sciaenops ocellatus)

Description: Results from the present study found for the first time that the use of bacterial strains of Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium thermophilum, and Enterococcus faecium from the commercial product PrimaLac® had the potential to act as a possible probiotic for juvenile red drum. The addition of PrimaLac® probiotics [whether as a water-soluble probiotic (WSP) or in a probiotic enhanced starter feed (PESF)] reduced mortality (%M), enhanced growth rates (MW, LT, SGR, and DGR), improved feed conversion efficiencies (FCEs), and physical condition factors in the juvenile red drum. Improvement was quantified using external morphological condition indices (MCIs) and blood physiological condition indices (PCIs). Results showed a strong positive relationship between MCIs and PCIs, which suggested that probiotics treated fish were in better health (lower MCIs) with lower fasting blood glucose and lactate levels than control fish. Addition of probiotics also resulted in improved water quality (lower nitrate, nitrite, and ammonia) in the treatment tanks compared to controls. Application of PrimaLac® probiotics on the morphology and histology of three different regions of the intestine (proximal, mid-and distal) improved intestinal length (Li), mass (Mi), and digesta mass (Md). In 5μm histological sections examined for differences among treatments (probiotics vs. controls), five variables within each intestinal region were also quantified: (i) perimeter ratio (PR) between the internal perimeter (IP) of the intestinal lumen and the external perimeter (EP) of the intestine where, PR = IP/EP; (ii) width of lamina propria (wLP); (iii) thickness of the muscle layer (tM); (iv) the number of goblet cells per segments (GC); and (v) height of enterocytes (hE). Overall, Li and Mi significantly increased by 13.4 ± 1.2% and 11.8 ± 0.9%, respectively, and Md decreased by 33.2 ± 1.21% compared to controls. Significant increases in microvilli heights, PR (by 21.3 ± 1.2%), tM (by 18.4 ± 0.9%), …
This item is restricted from view until December 1, 2021.
Date: May 2021
Creator: Busby, Wren Adell
Partner: UNT Libraries
open access

Breeding Ecology and Migratory Connectivity of Passerines in the World's Southernmost Forests

Description: In the extensive and remote sub-Antarctic forests of South America, birds are the dominant terrestrial vertebrates. Despite considerable efforts to understand the ecology of birds breeding in these forests, our current knowledge for many species is still incomplete. During three breeding seasons (2014 – 2017), I studied the breeding ecology of the five most abundant open-cup forest-dwelling passerines in the sub-Antarctic forest of Navarino Island, Chile (55°04′S, 67°40′W). There were differences in some of the breeding strategies used by birds breeding on Navarino Island versus conspecific populations breeding at lower latitudes. Milvago chimango was the main nest predator of open-cup nesting forest passerines, and the main cause of nest failure. In addition, I found that species built their nests in sites with higher density and taller understory; however, these two factors decreased their nest survival. This mismatch could be due to a change in depredation risk on Navarino Island, and thus, passerines breeding there may be in an ecological trap. In addition, using light-level geolocators, I determined that the migratory connectivity of Elaenia albiceps is weak as a result of the large spatial spread of individuals on the wintering ground, and that the distances among individuals on the breeding grounds are not maintained in the wintering grounds. My study opens further questions about the mechanisms driving differences in breeding strategies among populations. In addition, further research is needed to assess hypotheses that could explain the mismatch between nest-site selection and nest survival and to understand what drives elaenias' movements, not only during winter but throughout their annual cycle.
Date: May 2021
Creator: Jara Millar, Rocio Fernanda
Partner: UNT Libraries
open access

Change, Longing, and Frustration in Djent-Style Progressive Metal

Description: The progressive metal style "djent" emerged in the mid-to-late 2000s with bands that modeled their use of extended range instruments and complex rhythmic cycles after that of Swedish metal band Meshuggah. The addition of a new vocabulary of melody and harmony by bands such as Periphery, Tesseract, and Animals as Leaders has come to define djent in a new way and provided fruitful ground for voice-leading and metrical analysis. In this dissertation, I approach analysis in two steps. The first step is the production of detailed transcriptions of four djent songs. The process of transcription has allowed for the development of Transcription Preference Rules, modeled after Lerdahl and Jackendoff's preference rule approach in their Generative Theory of Tonal Music. The Transcription Preference Rules account for the selection of key signatures, time signatures, and other features of the scores that may affect analysis. Second, using these scores, I examine the connection between the textual topic of change and the voice-leading and metrical structures in Periphery's "Insomnia" and Tesseract's "Of Matter." I show how this topic is reflected by techniques such as change melodic direction, multidimensional metrical dissonance, and auxiliary cadential events. Finally, I apply voice-leading and metrical analysis to Animals as Leaders's "Tempting Time" and Mute the Saint's "Sound of Scars" in order to show what these analytical techniques reveal about instrumental djent pieces. I show how shifts in meter in "Tempting Time" can be represented cyclically. I conclude by showing how the interaction of metal and North Indian Classical techniques produces a unique representation of Mute the Saint's topic of longing and frustration in "Sound of Scars."
Date: May 2021
Creator: Sallings, Patrick N
Partner: UNT Libraries
open access

Client Narcissism and the Decision to Switch Tax Professionals

Description: Contentious interactions may arise between a tax professional and client upon a disagreement over a tax position. In an increasingly competitive tax return preparation market, these contentious interactions represent a significant threat to tax practitioners' client satisfaction and retention objectives. I conduct an experiment in which I examine the effect of three factors on tax clients' (1) likelihood to accept the advice of the tax accountant and (2) likelihood to switch tax accountants upon receiving professional advice counter to their preferred tax position. The three factors are: (1) clients' antagonistic narcissism; (2) clients' relationship with the accountant; and (3) how the advice is framed by the tax accountant. The results are based on a sample of 93 taxpayers. First, this study examines how clients' measured levels of narcissistic antagonism (hereafter, antagonism) impacts their reaction to "being told no" by their tax professional. Results indicate that upon the receipt of advice contrary to their preferences, highly antagonistic clients are more likely to (1) engage in a contentious interaction with their professional and (2) switch to a new tax professional. Supplemental path analyses document that individuals with high levels of antagonism cognitively react to instances of "being told no" by simultaneously devaluing their professionals' credibility and role as a client advocate, leading to these aggressive behaviors. This study also examines how the social closeness of the professional-client relationship influences the argue and switch decisions. Multivariate analysis indicates that social closeness is significantly related to the argue and switch decision. However, univariate results do not show significant relationship between social closeness and each of the decisions individually. That is, I find partial support for the professional publications and AICPA recommendations that tax practitioners should develop personal relationships with their clients to improve client satisfaction and likelihood of retention. Clients are marginally more likely …
Date: May 2021
Creator: Kaszak, Steven E
Partner: UNT Libraries
open access

Collaboration among Conflict Management Practitioners and Human Rights Advocacy Groups

Description: In a civil war, conflict management practitioners are concerned with bringing the conflict to an end and providing security for civilians. Similarly, human rights advocacy groups are also concerned with minimizing civilian harm. Given the similar intentions of these actors in civil war states, this dissertation explores under what circumstances conflict management practitioners and human rights advocacy groups collaborate. First, I compare to what extent mediation and peacekeeping cases differ with regards to showing signs of interaction; second, I compare how the level of interaction changes depending on whether peacekeeping missions are deployed by the United Nations or regional intergovernmental organizations. I find that human rights groups are more likely to interact with peacekeeping missions, especially when the missions are deployed by the United Nations. Moreover, I analyze to what extent the interaction between human rights groups and peacekeeping operations impacts how human rights groups carry out their advocacy efforts. The findings reveal that the way human rights groups use their advocacy efforts depend on whether the third parties providing peacekeeping operations respond to their requests.
Date: May 2021
Creator: Akyol, Seyma N.
Partner: UNT Libraries
open access

A Comparative Analysis of the Orchestral and Piano Versions of Finlandia by Jean Sibelius in Relation to His Compositional Style, 1899–1904

Description: While he was composing his important orchestral tone poem Finlandia in 1899–1900, Jean Sibelius (1865–1957) made his own piano arrangement of it. The purpose of this study is to compare the piano arrangement and orchestral version and to see further the similarities with Sibelius's other piano compositions from the same time period (1899-1904). Through this study I have found compositional patterns, which are typical for the composer and defined his composition style for piano during his "Kalevala-Romantic" phase. Sibelius's piano style was characterized as unpianistic and bulky by some. However, through my research I can show that with an analysis of certain harmonic structures, subtle use of pedal and correct voicings, his piano texture is indeed very thoughtful and transparent with a clear focus on counterpoint while remaining pianistic and comfortable to play. In order to fully understand the idiosyncrasies of the two versions of Finlandia, a detailed comparative analysis of the piano and orchestral scores is necessary. For this purpose, I primarily used the printed scores of both the piano and orchestral versions. In addition, the manuscript of the piano version of Finlandia was consulted as an important resource. From the orchestra manuscript, only one page has been found. The analysis focuses on the comparison between the textures of both versions, the score and the piano arrangement. I also applied the results of the comparison to the other scores of Sibelius's piano compositions from that time period to show his consistency in his use of the described arrangement techniques. With using the orchestration possibilities of the piano Sibelius's writing allows the instrument to stand completely on its own using all the possibilities of the piano sound while maintaining a highly pianistic texture. The goal of my research is to provide insight to understanding Sibelius's early piano style, introduce some …
Date: May 2021
Creator: Teppo, Ruusamari
Partner: UNT Libraries
open access

Comparison and Application of Verismo Singing Concepts to Trumpet Performance through Aria Transcription and Emulation

Description: The link between trumpet playing and emulation of the human voice has been acknowledged by a number of prominent teachers, authors, and composers since the inception of the trumpet as a melodic instrument. This dissertation is a pedagogical guide to lyrical trumpet performance based on the verismo style of singing consistent with the authentic interpretations of operatic soprano arias by Pietro Mascagni, Ruggero Leoncavallo, and Giacomo Puccini. Included are chapters that examine various aspects of the verismo style, as well as comparison and application of late 19th-century voice pedagogy to trumpet practice and performance. This resource examines six recordings of sopranos who created or popularized operatic roles during the verismo period. Included are transcriptions of the six arias for trumpet and piano, with performance notes based on dramatic and textual contexts, as well as interpretive aspects, namely tempo, dynamics, and vibrato.
Date: May 2021
Creator: Pratt, William
Partner: UNT Libraries

A Comprehensive Study of Three Compositions for Percussion by Composer Jonathan Leshnoff, "Run" (2003), "…without a chance" (2003), and "Concerto for Two Percussionists and Orchestra" (2011), including a Structural and Aesthetic Analysis

Description: Jonathan Leshnoff is one today's foremost contemporary American composers. His percussion compositions are significant compositions to the percussion solo, chamber, and concerto repertoire. This study is a tonal analysis on his marimba solo, Run (2003), with comparative analyses on his percussion chamber work, …without a chance (2002), and Concerto for Two Percussionists and Orchestra (2011).
This item is restricted from view until December 1, 2021.
Date: May 2021
Creator: Garcia, Jacob Adam
Partner: UNT Libraries
open access

Computational Studies of the Photophysical, Structural, and Catalytic Properties of Complex Chemical Systems

Description: Computational chemistry employs mathematical algorithms, statistics, and large databases to integrate chemical theory with experimental observations. Computational modeling allows us to make predictions concerning molecular properties and reactivity that ultimately lead to accurate assessment of the most important fundamental properties of chemical systems. Advances in theoretical techniques and computer power have dramatically increased the usefulness and importance of computational chemistry as a complement to experimental studies. This is especially relevant to catalytic reactions of industrial importance as well as the analysis of structural properties and the resulting spectroscopic phenomena in what are often otherwise counterintuitive models. This dissertation is a representation of the research I performed during my years as a graduate student in the Chemistry Department at the University of North Texas. My research has examined novel carbenes as efficient organocatalysts, structure-based design and optimization of small molecule drugs, and surveying methods to accurately describe structure and bonding and catalytic abilities of inorganic and organometallic systems. The works presented herein have been published or are awaiting submission to peer-reviewed scientific journals. A variety of computational techniques were employed in studying metal-mediated catalysis and organocatalysis as well as the structural and photophysical properties of systems containing closed-shell transition metal ions.
Date: May 2021
Creator: Melancon, Kortney
Partner: UNT Libraries

Continuing the Work of Our Ancestors: Black Radical Leadership and Disruptive Pedagogies in Affirming the Well-being of Black Students

Description: Using Black feminist thought and BlackCrit/critical race theory frameworks, this qualitative study examined Black educators' practices in addressing the behavior of their students in an urban school district. It utilized counternarratives and storytelling to explore the cultural dynamics at play between Black educators and their Black students. The Black educators in this study operated under several behavior systems, including positive behavioral interventions and supports (PBIS), socio-emotional learning (SEL), restorative practices (RPs), and zero tolerance policies (ZTPs). Such systems have been implemented based on research that they have the capacity to train Black students to make appropriate decisions regarding their behavior. These systems are also reinforced under the notion that they create learning spaces which promote academic achievement. Due to their own experiences and understanding about how institutional practices and disciplinary interventions result disproportionately in oppression and violence against Black students, these educators disrupted these practices and utilized cultural approaches that centered Black-ness. In doing so, they were able to address behavior and affirm Black students' well-being. The cultural approaches conceptualized as disruptive pedagogies include aspects of othermothering, otherfathering, critical caring, sermonizing, womanist caring, and Black masculine caring. An analysis of the stories and counternarratives illustrated that Black principals, counselors, and teachers draw from the long tradition of Black resistance and Black radical leadership to create educational spaces that support both emotional well-being and academic excellence. Implications, recommendations and future research are discussed.
This item is restricted from view until June 1, 2022.
Date: May 2021
Creator: Foster, Marquita Delorse
Partner: UNT Libraries

Crystallization and Lithium Ion Diffusion Mechanism in the Lithium-Aluminum-Germanium-Phosphate Glass-Ceramic Solid Electrolyte

Description: NASCION-type lithium-aluminum-germanium-phosphate (LAGP) glass-ceramic is one of the most promising solid electrolyte (SEs) material for the next generation Li-ion battery. Based on the crystallization of glass-ceramic material, the two-step heat treatment was designed to control the crystallization of Li-ion conducting crystal in the glass matrix. The results show that the LAGP crystal is preferred to internally crystalize, Tg + 60%∆T is the nucleation temperature that provides the highest ion conductivity. The compositional investigation also found that, pure LAGP crystal phase can be synthesized by lowering the amount of GeO2. To fill gap of atomic structure in LAGP glass-ceramic, molecular dynamic (MD) simulation was used to build the crystal, glass, and interfacial structure LAGP. The aliovalent ion substitution induced an simultaneously redistribution of Li to the 36f interstitial site, and the rapid cooperative motion between the Li-ions at 36f can drop the activation energy of LAGP crystal by decreasing the relaxation energy; furthermore, an energy model was built based on the time-based analysis of Li-ion diffusion to articulate the behavior. The glass and interfacial structure show and accumulation of AlO4, GeO4 and Li at the interface, which explains the Li-trapping on the intergranular glass phase. An in-situ synchrotron X-ray study found that, by using two-step heat treatment, the nucleation of Li-ion conducting crystal in the glass-matrix induced large strain from interfacial tension, which can also promote the incorporation of aliovalent ion substitution in the NASICON crystal and enhances the ion conductivity.
This item is restricted from view until December 1, 2021.
Date: May 2021
Creator: Kuo, Po Hsuen
Partner: UNT Libraries

Czech Opera Arias: An Anthology for Soprano

Description: This anthology of late 19th- and early 20th-century Czech opera arias for soprano focuses on works that lack existing scholarship, bridging the language gap through translations and pronunciation materials for English-speaking singers. Its 24 arias supplement the works of Smetana, Dvořák, and Janáček with those of contemporaneous composers Karel Bendl, Zdeněk Fibich, Josef Bohuslav Foerster, Karel Kovařovic, Vítězslav Novák, and Otakar Ostrčil. Its musicological scope provides vignettes of the musical-cultural landscape of Czech opera around the turn of the 20th century, the transformation of Czech declamation during that period, and the language knowledge needed to sing the works thereof. Chapter 2 elucidates the methodology used in the anthology's phonetic transcriptions and discusses the unique articulatory demands of singing in Czech. Chapter 3 grounds contemporaneous discussion of Czech declamation as late 19th- and early 20th-century composers and librettists sought to shape a musical voice suited to the features of their language. The following chapter is a look at Janáček's unique solution to this challenge. In Chapter 5, the relationship between criticism and composition is examined for these two faces of Czech modernism. Finally, Chapter 6 includes new performance editions of the arias curated for the anthology. Each aria is accompanied by an idiomatic translation, an inline phonetic transcription and word-for-word translation, a brief biographical introduction of the composer, and background information contextualizing the aria and the work from which it is derived. The objective of the anthology is to facilitate a broader range of well-informed performances of Czech repertoire as well as the acquisition of Czech lyric diction for singers at various experience levels.
This item is restricted from view until June 1, 2023.
Date: May 2021
Creator: Nichols, Brittany "Bree"
Partner: UNT Libraries

Deep Minima and Vortices for Positronium Formation in Positron-Hydrogen and Positron-Helium Collisions

Description: This dissertation work is a study of positronium formation for positron-hydrogen and positron-helium collisions in the Ore gap (the energy region between the threshold for ground-state positronium formation and the first excitation level of the target atom) using variational K-matrices. We have fitted the K-matrices using multichannel effective range theories and using polynomials. Using the variational K-matrices and their fits, we have located zeros in the positronium-formation scattering amplitude and corresponding deep minima in the positronium-formation differential cross section. The zeros are related to the vortices in the extended velocity field associated with the positronium-formation scattering amplitude. For positron-hydrogen collisions, we have found two zeros in the positronium-formation scattering amplitude, and corresponding deep minima in the positronium-formation differential cross section, while we have obtained a zero in the positronium-formation scattering amplitude for positron-helium collisions. We have connected the zeros in the positronium-formation scattering amplitude to vortices in the extended velocity fields. Our work shows that vortices can occur for charge exchange in atomic collisions.
This item is restricted from view until June 1, 2023.
Date: May 2021
Creator: Alrowaily, Albandari Wanes
Partner: UNT Libraries

Development and Exploration of End-User Healthcare Technology Acceptance Models

Description: This dissertation consists of three studies that collectively investigate the factors influencing the consumer adoption intention towards emerging healthcare technologies. Essay 1 systematically reviews the extent literature on healthcare technology adoption and serves as the theoretical foundation of the dissertation. It investigates different models that have been previously applied to study healthcare technology acceptance. Meta-analysis method is used to quantitatively synthesize the findings from prior empirical studies. Essay 2 posits, develops, and tests a comprehensive biotechnology acceptance model from the end-user's perspective. Two new constructs, namely, perceived risk and trust in technology, are integrated into the unified theory of acceptance and use of technology. Research hypotheses are tested using survey data and partial least square – structural equation modeling (PLS-SEM). Essay 3 extends the findings from the Essay 2 and further investigates the consumer's trust initiation and its effect on behavioral adoption intention. To achieve this purpose, Essay 3 posits and develops a trust model. Survey data allows testing the model using PLS-SEM. The models developed in this dissertation reflect significant modifications specific to the healthcare context. The findings provide value for academia, practitioners, and policymakers.
This item is restricted from view until June 1, 2023.
Date: May 2021
Creator: Wei, Xinyu
Partner: UNT Libraries
open access

The Development of Potential Therapeutic Anti-Myosin S2 Peptides that Modulate Contraction and Append to the Heart Homing Adduct Tannic Acid without Noticeable Effect on Their Functions

Description: This dissertation aimed to explore the S2 region with an attempt to modulate its elasticity in order to tune the contraction output. Two peptides, the stabilizer and destabilizer, showed high potential in modifying the S2 region at the cellular level, thus they were prepared for animal model testing. In this research, (i) S2 elasticity was studied, and the stabilizer and destabilizer peptides were built to tune contraction output through modulating S2 flexibility; (ii) the peptides were attached to heart homing adducts and the bond between them was confirmed; and (iii) it was shown that minor changes were imposed on the modulating peptides' functionality upon attaching to the heart homing adducts. S2 flexibility was confirmed through comparing it to other parts of myosin using simulated force spectroscopy. Modulatory peptides were built and computationally tested for their efficacy through interaction energy measurement, simulated force spectroscopy and molecular dynamics; these were attached to heart homing adducts for heart delivery. Interaction energy tests determined that tannic acid (TA) served well for this purpose. The stoichiometry of the bond between the TA and the modulating peptides was confirmed using mass spectroscopy. The functionality of the modulating peptides was shown to be unaltered through expansion microscopy where they located to the same position on the sarcomere with and without TA. They were also shown to cause the sarcomeres to contract similarly with and without the TA in contractility assay. Taken together, this work prepared the modulating peptides for animal model tests by attaching them to tannic acid.
Date: May 2021
Creator: Qadan, Motamed
Partner: UNT Libraries
open access

Early Intervention Referral and Service Frequency for Children with Visual Impairments: Experiences from the Field

Description: The purpose of this study was to examine differences in early intervention (EI) referral and service frequency for children with blindness or visual impairment (BVI) and gather information about the practices and experiences of vision professionals across the United States. The study focused on obtaining data from certified teachers of students with visual impairment (CTVI) and certified orientation and mobility specialists (COMS) in the United States. Information collected included descriptive statistics and professional information about EI for children with BVI, and information about the referral process and service frequency for children with BVI during EI. Thirty-three states were represented in the collected data. Of these states, 26 had responses from four or more professionals, the criteria for inclusion in the analyses. Participants provided information based on a researcher-developed survey requesting information related to the procedures used to provide EI services for children with BVI. Questions were adapted from established instruments where possible. Across states, there were some statistically significant differences in CTVIs and COMS reports of procedures regarding the role of professional collaboration, parent/caregiver participation in IFSP meetings, strengths/resources utilized by vision professionals, and challenges parents/families encountered when accessing EI services for their child with BVI. No statistically significant differences were identified across states for type of referral method, most commonly initiated by health care professionals, or method by which service frequency was determined. Results will be used to inform future research to further examine EI for children with BVI in the United States.
Date: May 2021
Creator: Bishop, Audra Lea
Partner: UNT Libraries
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The Early Songs (1880–1885) of Claude Debussy: An Analytical Approach to Defining a Repertoire

Description: The period between 1880 and 1885 was a significant time in Claude Debussy's life and compositional career. 1880 marks the date of his first published composition, "Nuit d'étoiles," and 1885 is the year in which he began his two-year tenure in Rome after winning the coveted Prix de Rome in 1884. During the intervening time Debussy composed about forty songs. Scholarly literature, especially analytical literature, tends to focus heavily on music in Debussy's mature style, often casting his early compositions in an unfavorable light. Writing on Debussy is scattered with references to the early songs but authors almost always situate them on one end of a continuum that shows an evolution of compositional style culminating in maturity. Such a view tends, if only tacitly, to regard early works as inferior instances of juvenilia rather than works worthy of study in their own right. In this dissertation I establish a foundation for regarding Debussy's early songs as significant compositions in their own right, independent from anachronistic comparisons with his more mature compositional style, and provide justification for considering the songs as a unified, identifiable repertoire within Debussy's larger œuvre. Using a modified Schenkerian analytical approach, I identify consistencies among the songs that give them an independent identity and provide support for their classification as an identifiable collection of works. I consider the songs within a proper historical narrative and in close association with poetry, French musical culture, and issues related to Debussy's biography. Furthermore, I delineate Debussy's compositional aesthetic in the early songs and examine his relationship to other notable contemporary composers of the mélodie, thus showing how his early style emerged from the tradition of the mélodie, how he participated in late-nineteenth century art-song culture, and how he ultimately pushed the genre of the mélodie forward.
Date: May 2021
Creator: Waldroup, William Allan
Partner: UNT Libraries

Effects of Surface Texture and Porosity on the Corrosion Behavior and Biocompatibility of Pure Zinc Biomaterials for Orthopedic Applications

Description: In this dissertation, small and large NaCl particle-derived surfaces (Ra > 40 microns) were generated on 2D Zn materials, and the surfaces were carefully studied concerning topography, corrosion behavior, and bone cell compatibility. Increases in surface roughness accelerated the corrosion rate, and cell viability was maintained. This method was then extended to 3D porous scaffolds prepared by a hybrid AM/casting technique. The scaffolds displayed a near-net shape, an interconnected pore structure, increasing porosity paralleled to an increased corrosion rate, an ability to support cell growth, and powerful antibacterial properties. Lastly, nano/micro (Rz 0.02–1 microns) topographies were generated on 2D Zn materials, and the materials were comprehensively studied with special attention devoted to corrosion behavior, biocompatibility, osteogenic differentiation, immune cell response, hemocompatibility, and antibacterial performance. For the first time, the textured nonhemolytic surfaces on Zn were shown to direct cell fate, and the micro-textures promoted bone cell differentiation and directed immune cells away from an inflammatory phenotype.
This item is restricted from view until December 1, 2021.
Date: May 2021
Creator: Cockerill, Irsalan
Partner: UNT Libraries
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