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The Impostor Phenomenon among Female High School Principals: A Mixed Methods Study (open access)

The Impostor Phenomenon among Female High School Principals: A Mixed Methods Study

The purpose of this sequential mixed-methods study was to explore the feelings, thoughts, critical incidents, and coping mechanisms of female high school principals and their experiences with the impostor phenomenon. A hierarchical multiple regression revealed that none of the demographic factors such as number of years as a head high school principal, age, percentage of female high school principals in the district, race/ethnicity, marital status, mentorship status, and community type, were statistically significant predictors of the varying levels of the impostor phenomenon. Eighteen female principals who represented an array of backgrounds and impostor phenomenon experiences were subsequently interviewed. The interviews were evaluated using interpretative phenomenological analysis. Seven themes, including several subthemes, emerged from the data. The themes were (1) childhood socialization, including the subthemes of gender roles, familial support, and early experiences of exclusion; (2) transitional uncertainty, including hiring self-doubt, school politics, and pressure to turn around a school; (3) the principalship, including relational leadership, constant pressure, and loneliness of the position; (4) critical incidents of the impostor phenomenon, including the subthemes of lack of experience, external criticism, and self-doubt; (5) gender issues, including a male dominated position, emotional capacity, and physical appearance, (6) coping strategies for the impostor phenomenon, …
Date: December 2020
Creator: Moriel de Cedeño, Daphne
System: The UNT Digital Library
Application of Novel Microporous Polyolefin Silica-Based Substrate in Paper Spray Mass Spectrometry (PS-MS) (open access)

Application of Novel Microporous Polyolefin Silica-Based Substrate in Paper Spray Mass Spectrometry (PS-MS)

This study addressed five key applications of paper spray mass spectrometry (PS-MS): (i) comparative analysis of the microporous substrate with the cellulose-based substrate in drug detection; (ii) detection of more than 190 fentanyl analogs with their fragmentation pattern can be implemented in the future reference for quicker, accurate and sensitive determination; (iii) exploring sweat in a fingerprint to be considered an alternate method to recognize non-invasive markers of metabolites, lipids, narcotics, and explosive residues that can be used in forensic testing applications; (iv) extending and improving better, cost-effective and quick real-time monitoring of the diseased stage using biofluid samples to obtain vastly different lipid information in viral infection such as COVID-19; and (v) mass spectral detection in chemical warfare agent (CWA) stimulant gas exposure with microporous structure absorbency capabilities in air quality monitoring. This novel synthetic material is known as Teslin® (PPG Industries), consisting of a microporous polyolefin single-layered silica matrix, can be used for precise, sensitive, selective, and rapid sample analysis with PS-MS. The Teslin® substrate provided longer activation time for samples and an active signal with a higher concentration of ion formation and mobility compared to cellulose-based papers. Direct analysis of multiple samples showed that, besides being more …
Date: December 2020
Creator: Weligamage De Silva, Imesha
System: The UNT Digital Library
Sociocultural Considerations and the Parallel Agendas of Music and Text in the Lullaby (open access)

Sociocultural Considerations and the Parallel Agendas of Music and Text in the Lullaby

This research is an investigation of how the lullaby, which is often viewed as purely a simple and pretty song, is a multifaceted vocal tradition that carries historical and cultural significance. As an exploration of how sociocultural factors impact the emotions expressed and the stories told in lullabies, this research encourages deeper examinations of lullaby texts in relation to the historical, cultural, and social aspects reflected in their textual themes. Through the close analysis of text and music of folk and art song lullabies, I propose that the lullaby's function extends beyond putting a baby to sleep; the further roles of the lullaby encompass cultural connections and therapeutic functions for both the parent and child. As a result of these sociocultural considerations, dialogue exists between the lullaby text and its music that do not always match the song's primary intent to provide peace and comfort.
Date: December 2020
Creator: Estwick, Brandi
System: The UNT Digital Library
Role of 5.8S rRNA in Zebrafish and Human Blood Coagulation (open access)

Role of 5.8S rRNA in Zebrafish and Human Blood Coagulation

Hemolytic disorders are characterized by hemolysis and are prone to thrombosis. Previously, it has been shown that the RNA released from damaged blood cells activates clotting. However, the nature of RNA released from hemolysis is still elusive. We found that after hemolysis, the red blood cells from both zebrafish and humans release 5.8S rRNA. This RNA activated coagulation in zebrafish and human plasmas. Using both natural and synthetic 5.8S rRNA and its synthetic truncated fragments, we found that the 3'-end 26 nucleotide-long RNA (3'-26 RNA) and its stem-loop secondary structure were necessary and sufficient for clotting activity. Corn trypsin inhibitor (CTI), a coagulation factor XII (FXII) inhibitor blocked 3'-26 RNA-mediated coagulation activation of both zebrafish and human plasma. CTI also inhibited zebrafish coagulation in vivo. 5.8S rRNA monoclonal antibody inhibited both 5.8S rRNA- and 3'-26 RNA-mediated zebrafish coagulation activity. Both 5.8S rRNA and 3'-26 RNA activates normal human plasma but did not activate FXII-deficient human plasma. Taken together, these results suggested that the activation of zebrafish plasma is via FXII-like protein. Since zebrafish has no FXII and hepatocyte growth factor activator (Hgfac) has sequence similarities to FXII, we knocked down the hgfac in adult zebrafish. We found that plasma from …
Date: December 2020
Creator: Alharbi, Abdulmajeed Haya M.
System: The UNT Digital Library
Re-Assessing Nationalism in the Art Songs of Jaime León (open access)

Re-Assessing Nationalism in the Art Songs of Jaime León

Colombian composer Jaime León (1921-2015) is known for his art songs. Most of the current scholarly literature about León defines him as a nationalist composer even though a majority of his songs do not appear to have nationalist traits. This document examines a representative selection of León's songs divided into three categories: songs influenced by the bambuco (the Colombian genre most present in his songs); songs whose text refers to Colombian culture; and songs without Colombian elements present in their text or music. After examination of these songs, my conclusion is that León, rather than being nationalist, was a cosmopolitan composer who used national elements as rhetorical tools in an isolated and experimental way.
Date: December 2020
Creator: Ávila Martínez, Juan Sebastián
System: The UNT Digital Library
Development and Disruption of Collateral Behavior and DRL Performances: A PORTL Exploration (open access)

Development and Disruption of Collateral Behavior and DRL Performances: A PORTL Exploration

One schedule of reinforcement that is used to decrease the rate of a target behavior is differential reinforcement of low rates (DRL). During this schedule, reinforcement is delivered for a target response if it occurs after a certain amount of time has passed since the last instance of this target response. The current study used a table-top game called PORTL and college student participants to investigate how collateral patterns develop and are disrupted during DRL schedules. After the participant developed a collateral pattern of behaviors with the objects, the researcher removed one of the objects that was part of the pattern and waited for a new pattern of behaviors to develop. Once the participant developed a new collateral pattern, the researcher removed a second object. This continued until there was only one object present. Results showed that the rate of reinforcement decreased following the removal of each object, then slowly increased as a new pattern developed.
Date: December 2020
Creator: Herzog, Leah
System: The UNT Digital Library
Job Satisfaction, Organizational Commitment, and Turnover Intention of Teachers Using Computer-Based Curriculum Delivery in a Drop-Out Recovery High School (open access)

Job Satisfaction, Organizational Commitment, and Turnover Intention of Teachers Using Computer-Based Curriculum Delivery in a Drop-Out Recovery High School

This current study examined the job satisfaction and turnover intention of teachers working in a drop out recovery program using online curriculum. The subjects of the study were from one charter school district in north Texas that is designated as a drop out recovery program. This qualitative case study used interviews and focus groups to examine eight different areas of teacher job satisfaction to examine factors that influence a teacher's intent to quit or remain at a school. Previous research showed a connection between job satisfaction levels and the intent of a teacher to terminate employment or not. Previous research had not looked into this specific school environment. Results showed that compensation was the largest factor in job satisfaction but negative feelings could be overcome if other areas of importance for teachers brought positive job satisfaction. Overall, teachers in this environment were more likely to have high job satisfaction and less likely to terminate employment.
Date: December 2020
Creator: Beauchamp, Joey
System: The UNT Digital Library
Epidemiologic Survey of a Unique Type of Task-Specific Dystonia in Brass Musicians (open access)

Epidemiologic Survey of a Unique Type of Task-Specific Dystonia in Brass Musicians

Brass musicians are known to experience a performance problem that is sometimes called valsalva maneuver or musical stuttering. This problem is known to cause difficulty starting a first note, tension in the throat, and tightness in the chest. Unfortunately, the research literature lacks sufficient details for evidence-based interventions. Therefore, the purpose of this study is to characterize and define this performance problem as experienced by brass musicians. An online epidemiologic survey was developed and deployed to collect data from brass musicians who have experienced this problem in their own playing. The survey was designed to acquire data in order to characterize and define the phenomenon through a biopsychosocial framework. The survey was also designed to assess whether this problem aligns with Altenmuller's heuristic model of motor control disruptions. A diverse group of brass musicians (n = 252) participated and offered relevant details for characterizing and defining this problem. Analysis of characteristic data suggests this problem is not a form of musical stuttering. Considering these data through Altenmuller's model suggests that this problem is experienced as a spectrum of motor disruptions that can develop into a unique type of musician's dystonia. While additional research is warranted, the results of this study …
Date: December 2020
Creator: Wallace, Eric (Trombonist)
System: The UNT Digital Library
User Privacy Perception and Concerns Regarding the Use of Cloud-Based Assistants (open access)

User Privacy Perception and Concerns Regarding the Use of Cloud-Based Assistants

Cloud-based assistants like the Google Home and the Amazon Alexa have become ubiquitous in our homes. Users can simply communicate with the devices using a smartphone application. There are privacy concerns associated with cloud-based assistants. For example, users do not know what type of information is being sent to the device manufacturer, if the device is stealthily listening to conversations, data retention, or who else has access to the data. Privacy is about perception. The goal of this study is to determine user privacy concerns regarding cloud-based assistants by adopting a quantitative research method. The study used a privacy decision framework that lists three core components, which are technology controls, understanding user privacy preference, and government regulations. The research used Dervin's sensemaking model to describe users' privacy perception using the privacy decision framework and improved on a privacy perception survey instrument from previous dissertations. An understanding of user privacy concerns with cloud-based assistants is required to provide a comprehensive privacy guidance to stakeholders. The significance of this study is in the identification of the privacy perception of users of cloud-based assistants and the extent to which the components of the theoretical framework can impact user privacy perception. The results of …
Date: December 2020
Creator: Awojobi, Abiodun
System: The UNT Digital Library
Class Enumeration and Parameter Bias in Growth Mixture Models with Misspecified Time-Varying Covariates: A Monte Carlo Simulation Study (open access)

Class Enumeration and Parameter Bias in Growth Mixture Models with Misspecified Time-Varying Covariates: A Monte Carlo Simulation Study

Growth mixture modeling (GMM) is a useful tool for examining both between- and within-persons change over time and uncovering unobserved heterogeneity in growth trajectories. Importantly, the correct extraction of latent classes and parameter recovery can be dependent upon the type of covariates used. Time-varying covariates (TVCs) can influence class membership but are scarcely included in GMMs as predictors. Other times, TVCs are incorrectly modeled as time-invariant covariates (TICs). Additionally, problematic results can occur with the use of maximum likelihood (ML) estimation in GMMs, including convergence issues and sub-optimal maxima. In such cases, Bayesian estimation may prove to be a useful solution. The present Monte Carlo simulation study aimed to assess class enumeration accuracy and parameter recovery of GMMs with a TVC, particularly when a TVC has been incorrectly specified as a TIC. Both ML estimation and Bayesian estimation were examined. Results indicated that class enumeration indices perform less favorably in the case of TVC misspecification, particularly absolute class enumeration indices. Additionally, in the case of TVC misspecification, parameter bias was found to be greater than the generally accepted cutoff of 10%, particularly for variance estimates. It is recommended that researchers continue to use a variety of class enumeration indices during …
Date: December 2020
Creator: Palka, Jayme M.
System: The UNT Digital Library
The Austrian Army in the War of the Sixth Coalition: A Reassessment (open access)

The Austrian Army in the War of the Sixth Coalition: A Reassessment

The Austrian army played a crucial role in Napoleon's decisive defeat during the War of the Sixth Coalition. Often considered a staid, hidebound institution, the army showed considerable adaptation in a time that witnessed a revolution in the art of war. In particular, changes made after defeat in the War of the Fifth Coalition demonstrate the modernity of the army. It embraced the key features of the new revolutionary way of war, including mass mobilization, a strategy of annihilation, and tactics based on deep echelonment, mobility, and the flexible use of varied formations. While the Austrians did not achieve the compromise peace they desired in 1814, this represented a political failing rather than a military one. Nevertheless, the Austrian army was critical in securing the century of general European peace that lasted until the dawn of the Great War.
Date: December 2020
Creator: Messman, Daniel M
System: The UNT Digital Library

Sources of Household Resilience during the 2018/2019 Saudi Floods

This research studied the relationship between social capital and household resilience. In particular, how bonding and bridging relationships affect household resilience was the question selected to illustrate this relationship between social capital and household resilience. Moreover, how the vulnerability of household impacts household resilience was also empirically examined. Social capital theory and vulnerability paradigm studies were used to discover explanations for why and how social connectedness and social vulnerabilities impact household resilience. Survey questionnaires were used to collect data in the main two cities in Saudi Arabia, Riyadh and Jeddah. A cross-sectional design was used to collect data. Statistical descriptions and inferences were conducted. In fact, multiple linear regression, T-test, and one way ANOVA were the three principal technics used to make statistical inferences. This study empirically found evidence there are relationships between bonding relationships and household resilience, and also relationships between the economic level of the household and household resilience. However, no evidence was found for relationships between bridging relationships and household resilience, or between other vulnerability factors and household resilience. Other vulnerability factors included gender, minority group, and language.
Date: May 2020
Creator: Alshammari, Abdullah Fahad
System: The UNT Digital Library
What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, Texas (open access)

What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, Texas

Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.
Date: May 2020
Creator: Proctor, Jayce Alan
System: The UNT Digital Library

The Consequences of Early Life Stage Thyroid Suppression on Immune Function in the Fathead Minnow (Pimephales promelas)

Current evidence suggests that thyroid hormones (THs) may impact development of the immune system. However, studies that explore the role of THs in immune development are limited, and the mechanisms leading to alterations in immune function are poorly understood. It is important to elucidate the role of THs in immune development given that many environmental contaminants have been shown to disrupt TH homeostasis and may also have negative impacts on the immune system. As such, the main goal of this study was to determine the long-term consequences of early life stage (ELS) hypothyroidism on immune function. To achieve this goal, it was first necessary to further characterize basic immune function in the selected model species, the fathead minnow (FHM, Pimephales promelas). Preliminary studies were conducted to describe the transcriptomic response to Yersinia ruckeri and adapt assays for the assessment of respiratory burst and phagocytic cell activity. To determine the long-term effects of ELS hypothyroidism, FHMs were exposed to the model thyroid suppressant propylthiouracil (PTU) from <1 to 30 days post hatch and reared under normal conditions. Upon reaching adulthood, ex vivo immune cell function and the in vivo immune response to Y. ruckeri were assessed. Fish exposed to PTU experienced …
Date: May 2020
Creator: Thornton Hampton, Leah Marie
System: The UNT Digital Library

A Top-Down Policy Engineering Framework for Attribute-Based Access Control

The purpose of this study is to propose a top-down policy engineering framework for attribute-based access control (ABAC) that aims to automatically extract ACPs from requirement specifications documents, and then, using the extracted policies, build or update an ABAC model. We specify a procedure that consists of three main components: 1) ACP sentence identification, 2) policy element extraction, and 3) ABAC model creation and update. ACP sentence identification processes unrestricted natural language documents and identify the sentences that carry ACP content. We propose and compare three different methodologies from different disciplines, namely deep recurrent neural networks (RNN-based), biological immune system (BIS-based), and a combination of multiple natural language processing techniques (PMI-based) in order to identify the proper methodology for extracting ACP sentences from irrelevant text. Our evaluation results improve the state-of-the-art by a margin of 5% F1-Measure. To aid future research, we also introduce a new dataset that includes 5000 sentences from real-world policy documents. ABAC policy extraction extracts ACP elements such as subject, object, and action from the identified ACPs. We use semantic roles and correctly identify ACP elements with an average F1 score of 75%, which bests the previous work by 15%. Furthermore, as SRL tools are often …
Date: May 2020
Creator: Narouei, Masoud
System: The UNT Digital Library

The Importance of Authenticity of Atmospheric Theming to Revisit Intention of Food and Beverage Venues in Theme Parks

Atmospheric theming is the use of the sensory experience in connection to a theme. The purpose of this research is to examine the effects of atmospherics with theming and their effects on customer behavior in food and beverage operations of a theme park. The official research questions developed for this study include: Does the impact of the authenticity of atmospheric theming influence an effect on revisit intention? Does the type of theme (land's theme or venue's theme) influence the effect of visitor revisit intention? These questions guided the current research in previously non-evaluated fields of study. This study used the Mehrabian–Russel (M-R) model to create a new research model. In the current study, atmospheric theming was the stimuli, emotional value was the emotional response, and visitor revisit intentions was the behavioral intention. Restaurant image was added to the model to obtain a cognitive reason.The results from the multiple regression indicated that all hypotheses were accepted. Restaurant image had a positive influence on both authenticity variables, and both authenticity variables had a positive influence on emotional value. Finally, emotional value was found to have a positive influence on revisit intention. These results indicated that atmospheric theming influenced revisit intention through emotional …
Date: May 2020
Creator: O'Dell, Billy Ray
System: The UNT Digital Library
A Performance Guide to George Enescu's Violin Sonata No. 3 in A Minor, Op. 25, Emphasizing Its Use of Romanian Lăutari Violin Techniques and Style (open access)

A Performance Guide to George Enescu's Violin Sonata No. 3 in A Minor, Op. 25, Emphasizing Its Use of Romanian Lăutari Violin Techniques and Style

In Romanian, the word lăutari refers to highly skilled professional Romani (Gypsy) musicians. By interacting with Romanian culture and tradition, the lăutari settled down in the country and developed a unique musical tradition. Their music is characterized by intricate, elaborate, and refined ornamentation; its execution requires a highly level of technique. George Enescu, regarded as Romania's most influential musician, was affected by lăutari music. He created a unique musical language that recreates Romanian character by using lăutari elements. This dissertation examines how to approach Enescu's Violin Sonata No. 3 and perform it by understanding the characteristics of lăutari music as well as the work's use of such lăutari violin techniques as diverse expressive slides, vibrato, double stops, various ornaments, artificial harmonics, imitation of folk instruments, and a variety of bow strokes. Enescu's Violin Sonata No. 3 is regarded as a challenging work in the violin literature requiring a high level of violin technique. Although the standard violin repertoire is enormous, many violinists are looking to rediscover new and challenging repertoire, distinguish themselves from others, and promote themselves as professional performers. Therefore, this study should help violinists to approach the idiomatic violin writing of Enescu's sonata, especially its lăutari techniques and …
Date: May 2020
Creator: Noh, Yuri
System: The UNT Digital Library

Perception of Falls and Confidence in Self-Management of Falls among Older Adults

Mobility safety, especially fall prevention, plays a significant role in successful aging for older adults. Fall preventive programs aim to reduce risks for mortality from fall-related injuries among older adults. However, the covariation between personal perceptions of falls and factors and confidence of self-management in falls (CSMoF) is still under-studied despite its importance to fall prevention. Using the International Classification of Functioning, Disability, and Health (ICF) model, this dissertation aimed to investigate the relative contribution of CSMoF in relation to fall risk self-perceptions while controlling for demographics and self-reported health and functioning. Participants were 691 older adults recruited from Area Agency on Aging at Arlington, Texas. They completed measures of physical functioning, CSMoF, fall risk perceptions and fear of falls. Regression analyses indicated that fear of falls was the most predictive factor of CSMoF among older persons. Physical function measures of age, chronic illnesses of metabolism, sensory impairment, and health status were also significant predictors of the CSMoF. The interaction of perception of falls and fall experience attenuated CSMoF, with physical functioning limitations. Fear of falls served as a mediator through which demographic predictors influence CSMoF. The joint effects of perception of falls and fear of falls likely explain CSMoF …
Date: May 2020
Creator: Li, Qiwei
System: The UNT Digital Library
Interlocal Competition and Local Fiscal Health (open access)

Interlocal Competition and Local Fiscal Health

A sizeable literature documents patterns of competition between local governments in metropolitan regions, while also exploring variation in such local government financial attributes as efficiency, budget size, fiscal disparity, and service equity, which are frequently bound together under the concept of fiscal health. However, the concept of fiscal health is broader and more sophisticated than any one fiscal measure, and empirical studies tend to focus only on multi-purpose governments. This study brings these concepts together to investigate how interlocal competition affects the fiscal health of different government types. This study answers three questions: What is a measure of fiscal health applicable to different government types? How does competition among cities and towns affect local fiscal health? How does the proliferation of special districts affect the fiscal health of local governments? This study measures the concept of fiscal health using factor analysis and examines the effects of competition among different government types on the fiscal health of both municipalities and special districts. Utilizing a pooled cross-sectional time-series approach and data from the U.S. Census Bureau for metropolitan statistical areas for every five years between 1972 and 2012,the study finds that competition among municipalities has adverse influences on the fiscal health of …
Date: May 2020
Creator: Park, Hyunggun
System: The UNT Digital Library

Fabrication of Nano-Channel Templates and a Study of the Electrical and Magnetic Properties of Nanowires Grown in Template Pores

This thesis is a study of the structural, electrical and magnetic properties of indium antimonide (InSb) nanowires (NWs), that were synthesized by a template-assisted ordered growth technique via electrochemical deposition. InSb was chosen for this study because of its intrinsic properties that make it a material of choice for applications in high channel mobility, infrared (IR) sensing, thermoelectrics, and magnetoresistive sensing martials. This work has four main components: (i) Growth in commercially available anodic aluminum oxide (AAO) template, where hole-dominated conduction was observed, following NW growth in a low pH electrolyte. The challenge in using these AAO templates was in covering the back surface of the pores with a metal film. Uncovered pores resulted in electrolyte leakage and non-reproducible results. (ii) Growth in flexible polycarbonate membranes, where the flexibility of the membranes resulted in polycrystalline or high defect density NW growth. (iii) Fabrication of an AAO template, where the barrier layer thinning technique was found to be efficient in removal of the think aluminum oxide barrier that exists at the interface between the template and the aluminum metal. This allows for direct growth of NWs into the template pores without the need for metal evaporation. (iv) Fabrication of a heterostructure …
Date: May 2020
Creator: Singh, Abhay Pratap
System: The UNT Digital Library
Charlotte Bray's "Here Everything Shines": Interview, Analysis and Performance Guide (open access)

Charlotte Bray's "Here Everything Shines": Interview, Analysis and Performance Guide

This dissertation examines a recent work for flute and piano, Here Everything Shines, by a living composer, Charlotte Bray, including a study, analysis and performance guide. The composition was largely inspired by the late Cape Verdean singer Cesária Évora and her song Petit Pays. My research explores the influence of Évora's song on Here Everything Shines, including the melodic development, tonal center, style and freedom of her singing and the impact the song has on a performer's interpretation of Here Everything Shines. The study examines the text of the song, the emotions evoked and reflects on the compositional elements in Here Everything Shines. Originally written for flute and guitar and commissioned by Tom Kerstens for International Guitar Foundation, Here Everything Shines was published in 2015. Bray transcribed it for violin and piano at request of Darragh Morgan and Mary Dullea and subsequently for flute and piano at my request. This dissertation compares the three versions for flute and guitar, violin and piano, and flute and piano and examines the variations between flute and violin as well as guitar and piano parts. The performance guide includes the composer's input on both interpretation and implementation of her ideas throughout the work.
Date: May 2020
Creator: Kuscer, Lana
System: The UNT Digital Library
The Determinants and Consequences of Having a Chief Operating Officer (open access)

The Determinants and Consequences of Having a Chief Operating Officer

This study examines the determinant and consequences of having a chief operating officer (COO). Specifically, we investigate chief executive officer (CEO) related factors that affect the choice to employ a COO and look into the impact of having a COO on firm operational efficiency using a data envelopment analysis (DEA)-based measure. Although prior literature has extensively investigated the role of CEOs and chief finance officers (CFOs) on firm outcomes, few studies focus on the impact of COOs. Thus, this study explores characteristics associated with the likelihood that a firm will have a COO. This research also sheds light on the effect of COOs on firm operational efficiency because the core duties of COOs include optimizing operational performance and improving cost efficiency. Our results imply that CEO busyness, CEO ability, CEO demographic characteristics, and CEO network size have a significant impact on the decision to employ a COO. We also find that firms that have a COO have a lower level of operational efficiency than firms that do not. This result implies that the cost of having a COO outweighs the benefit of having one. The effects last for three years on average. Further, we find that firms with a COO …
Date: May 2020
Creator: Le, Linh
System: The UNT Digital Library

Resurrection Attempts: Essays

This dissertation is composed of a critical preface, "Reconciling Art and Account in the Creative Essay," and the essay collection Resurrection Attempts: Essays. The preface situates the following essay collection within the genre of contemporary creative nonfiction. Specifically, it argues that genre-bending or genre hybridity are inherent and unavoidable features of creative nonfiction writing and should be celebrated, rather than denied or lamented. It points to other writers who deliberately challenge the bounds of genre, and discusses some of the collection's innovations in form and other ways it offers experimentation, such as use of unusual or borrowed points of view, disruption of chronology, and adoption of elements from other genres of writing, including fiction, poetry, and academic. Ultimately, embracing the artistic side of creative nonfiction (as opposed to its "purely" journalistic side) allows for heightened intimacy with the reader, a much wider breadth of storytelling, and a more vulnerable—and therefore more truthful—interrogation of legacy and the human experience. Resurrection Attempts is a collection of essays exploring the writer's rural Texas childhood and the early and tragic losses of her parents, including the effect of those experiences on her adult life and performance of motherhood. The voices of the writer's sisters …
Date: May 2020
Creator: Al-Qasem, Ruby
System: The UNT Digital Library
Inkjet Printed Transition Metal Dichalcogenides and Organohalide Perovskites for Photodetectors and Solar Cells (open access)

Inkjet Printed Transition Metal Dichalcogenides and Organohalide Perovskites for Photodetectors and Solar Cells

This dissertation is devoted to the development of novel devices for optoelectronic and photovoltaic applications using the promise of inkjet printing with two-dimensional (2D) materials. A systematic approach toward the characterization of the liquid exfoliated 2D inks comprising of graphene, molybdenum disulfide (MoS2), tungsten diselenide (WSe2), and 2D perovskites is discussed at depth. In the first study, the biocompatibility of 2D materials -- graphene and MoS2 -- that were drop cast onto flexible PET and polyimide substrates using mouse embryonic fibroblast (STO) and human esophageal fibroblast (HEF) cell lines, was explored. The polyimide samples for both STO and HEF showed high biocompatibility with a cell survival rate of up to ~ 98% and a confluence rate of 70-98%. An inkjet printed, biocompatible, heterostructure photodetector was constructed using inks of photo-active MoS2 and electrically conducting graphene, which facilitated charge collection of the photocarriers. The importance of such devices stems from their potential utility in age-related-macular degeneration (AMD), which is a condition where the photosensitive retinal tissue degrades with aging, eventually compromising vision. The biocompatible inkjet printed 2D heterojunction devices were photoresponsive to broadband incoming radiation in the visible regime, and the photocurrent scaled proportionally with the incident light intensity, exhibiting a …
Date: May 2020
Creator: Hossain, Ridwan Fayaz
System: The UNT Digital Library