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Analyzing the Joint Effects of Network and Community Attributes on Network Performance: Evidence from Local Continuum of Care Homeless Service Networks (open access)

Analyzing the Joint Effects of Network and Community Attributes on Network Performance: Evidence from Local Continuum of Care Homeless Service Networks

This dissertation examines the factors and combinations of factors that affect the performance of continuum of care homeless service networks, applying the configurational approach of contingency theory to data sets drawn from federal sources. The study accepts the two key assumptions from the theory: (1) that there are multiple paths to high performance and (2) key conditions have a joint influence on network performance. The data analysis in this study has two parts. The first employs OLS regression to examine the causal relationship between independent variables and the performance of permanent supportive housing (PSH) programs. This study also applies fuzzy set qualitative comparative analysis (fsQCA) to identify multiple combinations of factors that influence the performance of PSH programs. The results identify key factors and multiple combinations of factors that lead to high and low network performance. Federal CoC funding emerges as a core condition for high and low performance, but all relevant conditions can be critical factors depending on how they interact with other relevant conditions. This analysis helps expand the utility of existing contingency theory by using it to explain the dynamic interactions between factors in the context of public service networks. Ultimately, this dissertation confirms that fsQCA can …
Date: December 2023
Creator: Kim, Jintak
System: The UNT Digital Library

"Creature from the Unconscious"

Creature from the Unconscious is a reflexive genre hybrid film that follows the process of the director's journey of navigating the process of self-acceptance and self-love in the wake of trauma.
Date: December 2023
Creator: Powell, Madison Keely
System: The UNT Digital Library
The Impact of Kindergarten Classroom Assignment on Classroom Teachers and Student Achievement (open access)

The Impact of Kindergarten Classroom Assignment on Classroom Teachers and Student Achievement

To determine the impact of an administrator's decision on student placement in kindergarten classrooms, teachers were asked to share their perceptions on how that decision impacted their ability to deliver instruction and follow the district scope and sequence, as well as how that decision impacts student academic achievement and social and emotional development. This qualitative study was designed to gather data from kindergarten teachers using focus group interviews and individual interviews of campus principals from two campuses within the same district. The following two ways in which kindergarten classrooms were created were explored: (a) by random assignment or (b) knowledge of students' academic and behavioral performance based on information relevant to their Pre-K experience. Campus principal participants reported that they each chose their method to provide equity in the classrooms and fairness amongst their teachers. Teacher participants reported that overall, they preferred to have as much information about incoming students as possible and to be a part of the process of placing students into classrooms for the following year. By examining these teachers' perspectives, the findings from this study may positively influence policy and practice for campus administrators as they decide how they will place students in kindergarten classrooms. Continued …
Date: December 2023
Creator: Fountain, Angelica Brianna
System: The UNT Digital Library
Acenaphthene and 1,10-Phenanthroline-Fused Βeta-Functionalized Porphyrins (open access)

Acenaphthene and 1,10-Phenanthroline-Fused Βeta-Functionalized Porphyrins

A series of acene-fused porphyrins and 1,10-phenanthroline-fused porphyrins were synthesized and characterized via NMR spectroscopy and mass spectrometry. The acene-fused porphyrins exhibit unique optoelectronic properties, most notably they exhibit highly red-shifted absorption bands. The 1,10-phenanthroline-fused porphyrins are of interest for their ability to bond to as variety of metals to form chelation complexes.
Date: December 2023
Creator: Arvidson, Jacob Randall
System: The UNT Digital Library
Degradation Mechanisms and Dynamics of Silicon Telluride: A Guide to the Effective Fabrication and Characterization of Silicon Telluride-Based Devices (open access)

Degradation Mechanisms and Dynamics of Silicon Telluride: A Guide to the Effective Fabrication and Characterization of Silicon Telluride-Based Devices

Silicon telluride (Si2Te3) and many other tellurium containing compounds show emergent Raman peaks located at ~120 cm-1 and ~140 cm-1 as they age. The origin of these two emergent peaks is controversial in the literature and has been attributed to myriad causes such as the intrinsic Raman modes of the telluride materials, surface oxidation, defects, double resonances, and tellurium precipitates. The controversial nature of these peaks has led to the misidentification of highly degraded materials as pristine and to the misinterpretation of changes in Raman spectra. For the first time, quality thin film and bulk crystals of Si2Te3 are grown using a chemical vapor deposition (CVD) process. We then present a comprehensive and multimodal study of various Si2Te3 samples and find that the two emergent Raman peaks originate from tellurium nano-crystallites formed in the degraded surface layers of Si2Te3. The formation of the tellurium nano-crystallites are shown to be a result of a hydrolysis process in which Si2Te3 reacts with atmospheric water vapor. The challenges involved in the fabrication of Si2Te3 based devices are also discussed and ways in which degradation can be either prevented or reversed are demonstrated. Finally, we present preliminary data which shows promising low voltage switching …
Date: December 2023
Creator: Hathaway, Evan Allen
System: The UNT Digital Library
Glucose-Induced Developmental Delay is Modulated by Insulin Signaling and Exacerbated in Subsequent Glucose-Fed Generations in Caenorhabditis elegans (open access)

Glucose-Induced Developmental Delay is Modulated by Insulin Signaling and Exacerbated in Subsequent Glucose-Fed Generations in Caenorhabditis elegans

In this study, we have used genetic, cell biological and transcriptomic methods in the nematode C. elegans as a model to examine the impact of glucose supplementation during development. We show that a glucose-supplemented diet slows the rate of developmental progression (termed "glucose-induced developmental delay" or GIDD) and induces the mitochondrial unfolded protein response (UPRmt) in wild-type animals. Mutation in the insulin receptor daf-2 confers resistance to GIDD and UPRmt in a daf-16-dependent manner. We hypothesized that daf-2(e1370) animals alter their metabolism to manage excess glucose. To test this, we used RNA-sequencing which revealed that the transcriptomic profiles of glucose-supplemented wildtype and daf-2(e1370) animals are distinct. From this, we identified a set of 27 genes which are both exclusively upregulated in daf-2(e1370) animals fed a glucose-supplemented diet and regulated by daf-16, including a fatty acid desaturase (fat-5), and two insulin-like peptides (ins-16 and ins-35). Mutation of any of these genes suppresses the resistance of daf-2(e1370) to GIDD. Additionally, double mutation of ins-16 and ins-35 in a daf-2(e1370) background results in an increase in constitutive dauer formation which is suppressed by glucose supplementation. Further investigation of the insulin-like peptides revealed that ins-16 mutation in a wild-type background results in upregulation of …
Date: December 2023
Creator: Nahar, Saifun
System: The UNT Digital Library
Returning to Our Roots: An Anthropological Evaluation of the Farm to Keiki Program (open access)

Returning to Our Roots: An Anthropological Evaluation of the Farm to Keiki Program

Farm to school programs are becoming a popular intervention to address childhood obesity. The hope is to prevent later chronic illnesses such as diabetes and cardiovascular disease that can result from eating high-fat/high-calorie diets that are low in consumption of fresh fruits and vegetables. This study explores the impacts of one such program, Farm to Keiki, on students, their families, and teachers at two Native Hawaiian preschools on the island of Kauaʽi, Hawaiʽi. This program combined lessons about plants and nutrition with gardening at school and tastetesting in the classroom. Rooted in critical medical anthropology, this study utilized a combination of quantitative and qualitative methods to understand these impacts, as well as the historical and cultural contexts that have contributed to dietary changes among Native Hawaiians. Through in-depth interviews and focus groups, families and teachers described how the program encouraged the children to try new foods and eat more produce, and how the children demonstrated new knowledge about plants and healthy eating. Participants also spoke of ways in which their own knowledge and eating habits changed, and families reported carrying over many of the program's activities at home by gardening and preparing meals together. Additionally, participants offered valuable feedback on …
Date: December 2023
Creator: Migdol, Steven Jeffrey
System: The UNT Digital Library

Synthesis, Characterization, Standardization, and Validation of Luminescence Optical Chemosensors for the Detection of Carbon Dioxide, Aluminum Ions, and Silver Ions for Real-Life Applications

The presented dissertation encompasses three distinct investigations into novel complexes with diverse applications. Firstly, a Europium-based complex, K[Eu(hfa)4], exhibits remarkable potential for detecting dissolved CO2 in an ethylene glycol medium, offering a low limit of detection, rapid response times, and high signal-to-noise ratios. This complex demonstrates promise for quantifying CO2 concentrations and finds utility in sugar fermentation monitoring. Secondly, an innovative ratiometric optical sensor, Eu(tta)3([4,4'-(t-bu)2-2,2'-bpy)], showcases exceptional sensitivity and selectivity in detecting aluminum ions, making it suitable for environmental and biological applications. It exhibits reliable quantification in both methanol and aqueous samples, with remarkable accuracy validated by ICP-OES. Lastly, modifications to the Au3Pz3 complex synthesis enable the development of a silver ion sensor, paving the way for detecting silver ion leaching in real-life scenarios, such as silver nanoparticle-embedded bandages. The research extends to the synthesis of silver nanoparticles using various methods and foresees expanded in vitro and in vivo studies. These investigations collectively offer insights into the development of advanced sensing technologies with significant implications for a wide range of practical applications.
Date: December 2023
Creator: Perera, Nawagamu Appuhamilage Kasun
System: The UNT Digital Library
The Saxophone Meets Chinese Culture: A Guide to Works for Saxophone by Composer Zou Xiangping (open access)

The Saxophone Meets Chinese Culture: A Guide to Works for Saxophone by Composer Zou Xiangping

Zou Xiangping is one of the most significant Chinese composers who writes music for the saxophone. These works, however, are not well-known in the classical saxophone repertoire. The purpose of this dissertation is to help international saxophonists develop an enlightened understanding and ultimately, performance of two selected pieces by Chinese composer Zou Xiangping (邹向平) (b. 1951), Images of Yalong River for Alto Saxophone and Piano (雅砻江印:为中音萨克斯管和钢琴) and Song of Chuanjiang River Boatman for Saxophone Quartet (川江纤夫之歌: 为萨克斯管四重奏) (2022). The compositional background, the relevant introduction about Chinese culture, the manner in which the composer combined this with Western compositional techniques, and comprehensive performance advice of each piece are provided.
Date: December 2023
Creator: Zhang, Cehuai
System: The UNT Digital Library
Using GIFs and Matrix Training to Teach Noun-Verb Tacts to Children with Autism (open access)

Using GIFs and Matrix Training to Teach Noun-Verb Tacts to Children with Autism

Verbal behavior is a critical repertoire for children with autism spectrum disorder to acquire. Tacts—verbal behavior evoked by nonverbal stimuli—are important for communicating about the world around oneself. Noun-verb tacts are part of a robust tact repertoire and may be addressed during applied behavior analytic intervention. When acquiring noun-verb tacts, it is important that the speaker learn to respond to many variations of stimuli like novel combinations of learned nouns and verbs, which is called recombinative generalization. One strategy to teach multi-component targets, such as the noun-verb tact, and lead to recombinative generalization is matrix training. Matrix training is a framework utilized to arrange targets that can be combined in order to facilitate recombinative generalization by teaching a subset of combinations and then probing others. With three children with ASD, we used matrix training and evaluated the acquisition of trained and novel combinations of noun-verb tacts with GIFs as stimuli arranged in three matrices. We used a concurrent multiple probe design across sets, and our results indicated that all participants acquired trained noun-verb tact targets in the presence of the GIFs. The degree of recombinative generalization varied across participants, but each participant demonstrated recombinative generalization with some stimuli. We analyzed …
Date: December 2023
Creator: White, Alexandria Blayce
System: The UNT Digital Library

Transport of Proton, Hydrogen and Alpha Particles through Atomic Hydrogen Environment

Using multiple theoretical methods, comprehensive calculations are performed to create a new and more comprehensive data set for elastic scattering and related transport cross sections for collisions of (H$^+$ + H), (H + H) and (He$^{2+}$ + H) in the center-of-mass energy frame. In proton-atomic hydrogen collisions, we have significantly updated and extended previous work of elastic scattering, charge transfer and related transport integral and differential cross sections in the center-of-mass energy range $10^{-4} - 10^4$ eV where the multi-channel molecular orbital approach (MO3) is used. For atomic hydrogen-hydrogen collisions, similar updates have been made of elastic scattering and spin exchange differential and integral cross sections, also for the H + H collision the ionization and negative ion formation cross sections are provided in energy range (1-20 KeV) by use of the 'hidden crossing' theoretical framework. For collisions of alpha particles with atomic hydrogen we have computed the elastic scattering cross section in the center-of-mass energy range $10^{-4} - 10^8$ eV. In this case, at the lowest energies where elastic scattering greatly dominates other reaction channels, a single-channel quasi-molecular-orbital approach (MO1) is used. With the opening of inelastic channels at higher energies the multi-channel atomic-orbital, close-coupling method is applied, and …
Date: December 2023
Creator: Zaman, Tamanna
System: The UNT Digital Library
Teacher Perceptions of Innovative Learning Environments: Implications for Leaders (open access)

Teacher Perceptions of Innovative Learning Environments: Implications for Leaders

Innovative Learning Environments are increasingly built and implemented in schools, but are not necessarily being used according to designers' intentions. The goal of this study was to examine teacher perceptions of the innovative learning spaces they were charged with using and to determine if they were being used effectively and as designed. The research was guided by three basic questions: what were the teachers' perceptions of these spaces, was the teacher pedagogy need to change to accommodate the space, and did the teacher feel support by campus leadership. The fourth research question centered around the goals and vision of the design team that created the innovative learning space. The crux of the issue was that the districts vision for the space came to fruition once the teachers were in the actual space with the students. This qualitative study interviewed seven teachers in the educational setting and separately interviewed the design team. The results indicated that some of the teachers were unaware of the definition of an innovative space and believed that they were utilizing the space in ways that met the designs of the campus leadership. Furthermore, teachers felt the new designs caused a classroom management issue as well as …
Date: December 2023
Creator: Elliott, Robyn Kaye
System: The UNT Digital Library
Predictors of Academic Success in an Early College Entrance Program (open access)

Predictors of Academic Success in an Early College Entrance Program

Early college entrance programs have existed in the United States since the 1950s, but in-depth research on academic success in these programs is lacking. Every year, early college entrance programs utilize a variety of data-gathering and candidate-screening techniques to select hundreds of students for admission into these accelerated programs. However, only a smattering of research articles has discussed the factors that predict academic success in these programs. This exploratory study investigated commonly-relied-upon admissions data points—such as high school GPA and ACT scores—and demographic information—such as sex, ethnicity, and locality—to see if any of these factors predicted academic success: namely, graduation and early college entrance program GPA. Secondary data from nearly 800 students admitted over an 11-year period to a state-supported, residential early college entrance program located at a large Southern university in the United States were utilized for this study. Logistic regression failed to yield a model that could accurately predict whether or not a student would graduate from the program. Multiple regression models showed that high school GPA and ACT scores were predictive of performance, and that factors like locality and ethnicity can have predictive power as well. However, the low variance in performance explained by the variables included …
Date: December 2023
Creator: Earls, Samuel Wayne
System: The UNT Digital Library
The Effects of Specific and Disguised Mands on Staff's Reinforcer Delivery (open access)

The Effects of Specific and Disguised Mands on Staff's Reinforcer Delivery

Residential facilities for adults with developmental disabilities offer essential accommodations and support services, with fostering communication for residents as an important aspect of care. Despite the importance of communication, previous research has identified concerns about staff performance (SP) in facilitating positive social interactions, such as engaging in consequent-mediating behavior for residents' mands. Previous research has primarily focused on improving SP through skills-based training. Yet, Skinner's theory of verbal behavior emphasizes the social and reciprocal nature of mands. Skinner suggests that the listener's behavior, engaging in consequence-mediating behavior, must be conditioned by the verbal community. However, empirical investigations into the reinforcing practices of staff in residential facilities, such as the shaping and sustaining of different types of resident mands, is limited. The current investigation sought to address this gap in research by evaluating if distinct mand topographies, disguised or specific mands, influenced the likelihood of staff engaging in consequence-mediated behavior across three staff-resident dyads. Results suggest a low probability of staff responding to, or reinforcing, mands, thus limiting conclusions on the effects of mand topographies on staff performance. Future directions and considerations regarding resident-staff interactions are discussed.
Date: December 2023
Creator: Richey, Caroline Nicole
System: The UNT Digital Library

Development and Characterization of Compliant Bioelectronic Devices for Gastrointestinal Stimulation

In this research, we aimed to develop thin-film devices on a polymer substrate and an alternative 3D-printed device with macroelectrodes for treating gastrointestinal (GI) conditions. First, the fabrication of thin-film devices was demonstrated on a softening thiol-ene/acrylate polymer utilizing titanium nitride (TiN) as electrode material. This was achieved by utilizing cleanroom fabrication processes such as photolithography, wet and dry etching. The functionality of the device was shown by performing electrochemical characterization tests, mainly cyclic voltammetry, electrochemical impedance spectroscopy, and voltage transient. We synthesized a novel thiol-ene/acrylate polymer based on 1,3,5-triallyl-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (TATATO), trimethylolpropanetris (3-mercaptopropionate) (TMTMP), and polyethylene glycol diacrylate (PEGDA). We show that this stretchable shape memory polymer substrate is well suited for cleanroom processes. Finally, for the high throughput of the wearable devices with electrodes size 10 mm in diameter, we implemented single electrode fabrication using printed circuit boards (PCBs) and depositing gold (Au) and TiN on the plated side of PCBs utilizing the sputtering tool. This step was followed by the assembly of those single electrodes on the flexible 3D printed device. We showed that the TiN electrode material performed better in terms of charge storage capacity and charge injection capacity than the widely used stainless steel electrode material …
Date: December 2023
Creator: Chitrakar, Chandani
System: The UNT Digital Library

Directing Transition Metal Catalysis of Second and Third Row Metals through Ligand Design

Ligand design is important due to a ligand's ability to tune properties of the transition metals, such as catalytic activity and selectivity. Gold(I) catalysts can be directly impacted by ligands electronically as well as with steric bulk when undergoing enantioselective and regioselective reactions. In the dissertation, a series of gold(I) acyclic diaminocarbenes were synthesized and used to explore the 1,6 enyne cyclization/hydroarylation. The use of metal templated synthesis of the gold(I) acyclic diaminocarbenes allowed for the gradual increase in steric bulk of the catalysts. In the end, it was shown that electronics play the major role in the regioselectivity for the 1,6 enyne cyclization/hydroarylation but localized steric bulk can control the catalytic reaction if placed strategically. Cross-coupling reactions used to form carbon-carbon or carbon-heteroatom bonds are important in the production of pharmaceutical chemicals on a large scale. Iron, an extremely cheap and earth abundant first row transition metal, has had some success in cross-coupling reactions. Iron does not go through the same catalytic cycle for cross-coupling as most transition metals, the most common of which is palladium. In the dissertation, a ligand was developed to induce Iron to undergo the same cycle as palladium. In addition, the same ligand was …
Date: December 2023
Creator: Nguyen, John
System: The UNT Digital Library
Sonorous Andean Landscapes: A Performance Guide for Guevara Ochoa's "Yaraví, Danza y Huayno" (n.d) and Vivanco's "Fantasía Andina" (c. 1988) (open access)

Sonorous Andean Landscapes: A Performance Guide for Guevara Ochoa's "Yaraví, Danza y Huayno" (n.d) and Vivanco's "Fantasía Andina" (c. 1988)

Peruvian composers Armando Guevara Ochoa (1926–2013) and César Vivanco (b. 1949) borrow and transplant musical elements from Andean folk tradition into their compositions for the modern classical flute. Guevara Ochoa's Yaraví, Danza y Huayno and Vivanco's Fantasía Andina are solo flute pieces rooted in Peruvian folklore traditions and Andean instrumental performance. The purpose of this dissertation is to provide flutists with technical and interpretative guidance in preparing these pieces. Yaraví, Danza y Huayno, a suite of three short dances, and Fantasía Andina, a free-meter piece in an improvisational style, incorporate elements that utilize the performance techniques of Andean instruments, with use of quotations from traditional Andean folk music. References to quenas (traditional vertical flutes), zampoñas (panpipes), pututos (ceremonial natural horns), charangos (Andean guitars) and Andean harps are integrated within the works and fused with themes borrowed from iconic pieces such as El cóndor pasa, and traditional harmonic, melodic and rhythmic structures of the huayno (fast festive dance) and yaraví (slow melancholic song). The techniques and traditions borrowed from Andean folk music are not notated in these scores due to the limitations of musical notation. Performers are expected to portray the Andean musical identity of the composers' intent. This dissertation assists …
Date: December 2023
Creator: Romo Bocanegra, Jossecarlo
System: The UNT Digital Library
FruitPAL: An IoT-Enabled Framework for Automatic Monitoring of Fruit Consumption in Smart Healthcare (open access)

FruitPAL: An IoT-Enabled Framework for Automatic Monitoring of Fruit Consumption in Smart Healthcare

This research proposes FruitPAL and FruitPAL 2.0. They are full automatic devices that can detect fruit consumption to reduce the risk of disease. Allergies to fruits can seriously impair the immune system. A novel device (FruitPAL) detecting fruit that can cause allergies is proposed in this thesis. The device can detect fifteen types of fruit and alert the caregiver when an allergic reaction may have happened. The YOLOv8 model is employed to enhance accuracy and response time in detecting dangers. The notification will be transmitted to the mobile device through the cloud, as it is a commonly utilized medium. The proposed device can detect the fruit with an overall precision of 86%. FruitPAL 2.0 is envisioned as a device that encourages people to consume fruit. Fruits contain a variety of essential nutrients that contribute to the general health of the human body. FruitPAL 2.0 is capable of analyzing the consumed fruit and then determining its nutritional value. FruitPAL 2.0 has been trained on YOLOv5 V6.0. FruitPAL 2.0 has an overall precision of 90% in detecting the fruit. The purpose of this study is to encourage fruit consumption unless it causes illness. Even though fruit plays an important role in people's …
Date: December 2023
Creator: Alkinani, Abdulrahman Ibrahim M.
System: The UNT Digital Library
The Impact of Leadership on School Culture and Teacher Retention (open access)

The Impact of Leadership on School Culture and Teacher Retention

To determine the impact that school leaders have on school culture and teacher retention, a sequential explanatory mixed methods approach was used to study schools in a district feeder pattern in in a large, suburban district in Texas with a student population of approximately 25,000. In Phase 1, teachers at one elementary, one middle, and one high school were asked to complete a 26-question Likert scale survey about school culture. The last statement in the survey asked participants if they were willing to participate in a focus group about school culture and teacher retention. In Phase 2, focus group interviews were conducted with volunteer participants who took the survey and stated they would be interested in participating in a focus group. Three focus groups were held to divide the participants by grade level grouping taught: elementary, middle, and high school. Focus group participants stated that they believe school leaders play a vital role in creating the culture of the school and in teachers' desire to remain not only teaching at their school, but also remaining in the field of education. The survey data supported these findings. By examining teachers' perspectives, the findings of the study may positively inform and influence …
Date: December 2023
Creator: Spaulding, Shelly
System: The UNT Digital Library
Kinetics and Thermochemistry of Halogen and Nitrogen Compounds (open access)

Kinetics and Thermochemistry of Halogen and Nitrogen Compounds

Halogen and nitrogen containing compounds play a key role in the atmospheric chemistry of the Earth. Through a mixed computational and experimental approach, the kinetics of these compounds with radicals common to the atmosphere have been explored. Using fundamental measurements such as the IR absorption cross-section, the rate constants of atmospheric reactions and the properties of product molecules have been derived. These results have been further extended to environmental applications such as the Global Warming Potential for a species. The present results can be used as a calibration for further experiments and as checks on computational predictions of environmental properties. Such modeling can aid in the development of future industrial reagents that are less hazardous to the atmosphere.
Date: December 2023
Creator: Rawling, George
System: The UNT Digital Library

Surface Engineering of Materials for Beyond-Microelectronics

All oxide heterostructure Cr2O3/TiO2-x was deposited on Al2O3(0001) single crystal via MBE. The analysis of interfacial interactions involving two metal oxides resulting in magnetic properties gave insights for using such heterostructures as potential spintronic device materials. The corundum phase epitaxial growth of TiO2-x on Al2O3 was characterized using XPS, AES, EELS, and LEED. The data obtained gives evidence of presence of two-dimensional electron gas at titania surface due to oxygen vacancies formation after deposition. On titania, the deposition of chrome in UHV results in the formation of oxidized chromia overlayer by abstraction of oxygen from the TiO2-x underlayer further increasing the number of vacancies present. In industrial R&D project, dry etching of multiple optical device components was performed using a novel angled etch prototype tool. The first set of experiments involved plasma etching of SiC thin films optimized for target application. The best-known method (BKM) worked from 300mm full wafer to 200mm product. In second experimentation, a variety of gray-tone photoresist received from customers were etched using BKM. Customer received etch rate on each gray-tone material. The third experiments compared recipe R1 to test recipe R2 on the test vehicle VDC. R2 showed faster etch rate but lower process repeatability …
Date: December 2023
Creator: Anwar, Fatima
System: The UNT Digital Library

A Pedagogical Analysis of "Seven Chinese Folk Songs" by Wanghua Chu

Wanghua Chu (b. 1941) is an outstanding Chinese composer and pianist, who has written extensively for piano. This dissertation offers a pedagogical analysis of Seven Chinese Folk Songs (1999), one of his most famous and well-regarded piano solo works. The present study has two broad and related aims: to introduce Wanghua Chu's Seven Chinese folk songs to a broader community of pianists outside of China; and to provide a pedagogical analysis so that pianists of a late-intermediate level and higher can learn it effectively and teachers can teach it successfully. Chapter 2 provides an overview of Wanghua Chu's artistic career and major works, as well as the composition background of Seven Chinese Folk Songs. Chapter 3 introduces the seven original Chinese folk songs that are used in this work, both the actual songs and the song types. Chapter 4 provides an analysis of the musical form of each movement of Seven Chinese Folk Songs. Chapter 5 analyzes the technical difficulties of this work and provides specific practice methods to solve them. Seven Chinese Folk Songs exposes the pianist to the diversity and richness of Chinese folk songs and offers them a different kind of learning opportunity in which they not …
Date: December 2023
Creator: Chen, Zhaodong
System: The UNT Digital Library
A Comprehensive Investigation of Photoinduced Electron Transfer and Charge Transfer Mechanisms in Push-Pull Donor-Acceptor Systems: Implications for Energy Harvesting Applications (open access)

A Comprehensive Investigation of Photoinduced Electron Transfer and Charge Transfer Mechanisms in Push-Pull Donor-Acceptor Systems: Implications for Energy Harvesting Applications

Donor-acceptor systems exhibit distinctive attributes rendering them highly promising for the emulation of natural photosynthesis and the efficient capture of solar energy. This dissertation is primarily devoted to the investigation of these unique features within diverse donor-acceptor system typologies, encompassing categories such as closely covalently linked, push-pull, supramolecular, and multi-modular donor- acceptor conjugates. The research encompasses an examination of photosynthetic analogs involving compounds such as chelated azadipyromethene (AzaBODIPY), N,N-dimethylaminophenyl (NND), phenothiazine (PTZ), triphenylamine (TPA), phenothiazine sulfone (PTZSO2), tetracyanobutadiene (TCBD), and expanded tetracyanobutadiene (exTCBD). The strategic configuration of the donor (D), acceptor (A), and spacer elements within these constructs serves to promote intramolecular charge transfer (ICT), which are crucial for efficient charge and electron transfer. The employment of cutting-edge analytical techniques, such as ultrafast transient absorption spectroscopy, is integral to the study. Furthermore, a comprehensive suite of analytical methodologies including steady-state UV-visible absorption spectroscopy, fluorescence and phosphorescence spectroscopies, electrochemical techniques (including cyclic voltammetry and differential pulse voltammetry), spectroelectrochemistry, and density functional theory calculation (DFT), collectively contribute to the comprehensive characterization of push-pull donor-acceptor systems, with a particular emphasis on their potential as highly effective solar energy harvesting application.
Date: December 2023
Creator: Alsaleh, Ajyal Zaki
System: The UNT Digital Library

The Effect of Developmental Hypoxia on Cardiac Physiology in Three Species: Alligator mississippiensis, Chelydra serpentina, and Danio rerio

In this dissertation, I explored the effects of developmental hypoxia on heart contractility in three separate species of ectotherms: the common snapping turtle (Chelydra serpentina), the American alligator (Alligator mississippiensis), and the zebrafish (Danio rerio). I began with the common snapping turtle and tested whether the utilization of the sarcoplasmic reticulum was altered in response to developmental hypoxia. In the next two chapters, developmental hypoxia of the American alligator was explored studying how the cardiac tissue was affected, specifically in physiological stressors, sarcoplasmic reticulum utilization and sensitivity to pharmacological increases in contractility. The last chapter explored how zebrafish heart contractility was altered in response to chronic hypoxia from egg to adult. Findings from these chapters suggest that while developmental hypoxia did alter cardiac contractility, it did not alter the response of the heart to physiological stressors such as increased heart rate or under hypoxia. Overall, these findings contribute to increasing the current understanding of how developmental hypoxia alters the cardiovascular system but with an emphasis on the cardiac tissue level.
Date: December 2023
Creator: Smith, Brandt Ragan
System: The UNT Digital Library