Porphyrins offer a very synthetically flexible template which can be modified in numerous ways to synthesize molecules with very useful properties applicable in areas such as non-linear optical properties, photodynamic therapy, dye-sensitized solar cells, chemical sensors and organic electronic devices. β-Substituted π-extended porphyrins offer unique capabilities in tuning the properties of the molecule towards practical applications. Increased π-conjugation allows the HOMO-LUMO gap to decrease and hence to redshift the absorption into the near-IR region. β-Fused benzoporphyrins offer additional benefits in which the benzene ring itself can be further modified using electron donating substituents and electron donating substituents to electronically tune these porphyrins for various uses. The goal of the research pursued in this dissertation was to develop new methods for the development of β-Substituted π-extended porphyrins and to study their optical and electronic properties. To accomplish this goal, we developed new method to synthesize A2B2 type tetrabenzoporphyrins and we studied the electron transfer in such systems. We also studied the effectiveness of such systems in dye sensitized solar cells. A new method to synthesize functionalized naphthalene fused porphyrins was also developed and we were also able to use this method to synthesize a push-pull naphthalene fused porphyrin.

Through a series of carefully designed experiments, characterization and some modeling tools, this work is aimed at studying the role of thermal profiles on different microstructural zones and associated properties like strength and corrosion through a variation of weld parameters, thermal boundary conditions and material temper. Two different alloys belonging to the Al-Cu and Al-Cu-Li system in different temper conditions- peak aged (T8) and annealed (O) were used. A 3D-thermal pseudo mechanical (TPM) model is developed for the FSW process using heat transfer module in COMSOL Multiphysics and is based on a heat source wherein the temperature dependent yield shear stress is used for the heat generation. The precipitation and coarsening model is based on the Kampmann and Wagner theoretical framework and accounts for the competition between the various nucleation sites for both metastable and equilibrium precipitates. The model predicts different precipitate mean radius and volume fraction for the various zones in the friction stir welded material. A model for the yield strength is developed which considers contributions from different strengthening mechanisms. The predictions of the each models have been verified against experimental data and literature. At constant advance per rotation, the peak temperature decreases with a decrease in traverse …

Poor post-school outcomes for young adults with an autism spectrum disorder (ASD) have underscored the need to gain insight into the use of evidence-based practices (EBPs) in the planning and implementation of transition services. EBPs for effective transition planning and implementation have been documented in the literature but do not appear to be fully utilized in practice to achieve desired student outcomes, reflecting a research-to-practice gap. EBPs have the potential to produce positive outcomes at the high school level, if implemented with fidelity. Special education personnel, especially administrators, play a vital and unique role in transition planning. They can either facilitate or hinder the process. This phenomenological study investigated the perceptions of public school administrators regarding the extent of their awareness of EBPs to ensure the successful transition of students with ASD and associated barriers. Semi-structured interviews were conducted with 10 secondary-level public school administrators. Major themes identified through analyzing the qualitative data included (a) a positive vision for students with ASD, (b) characteristics of a good transition program, (c) administrators' roles in the transition process, (d) barriers to EBP implementation, (e) strategies to reduce barriers, and (f) ownership of what administrators can do to remedy the problem. Lastly, the …

The northern bobwhite (Colinus virginianus) population decline is a severe, rangewide phenomenon beginning >150 years ago and continuing today. In this investigation, I: 1. document the timeline of bobwhite population decline and unintended genetic consequences of attempted remedies, 2) develop a model useful for predicting possible locations of potentially sustainable bobwhite populations in semiarid rangeland in Texas and Oklahoma, and 3) examine the relationship between population monitoring data and meteorological factors. While breeding season call counts of male bobwhite have been used for >70 years to provide estimates of fall populations for hunting, most studies of call counts have focused on mathematics and statistical accuracy of the count, largely overlooking the influence of meteorological factors on call counts. Here, I present the results of >4,400 individual point counts and examine their relationship with meteorological variables recorded at each stop. Humidity was positively correlated with the number of birds recorded (ρ = 0.275, p < 0.001) and temperature was negatively correlated (ρ = -0.252, p < 0.001). The number of birds recorded was significantly higher in wet years than in drought years. There was no significant correlation between wind velocity and number of birds recorded. These results suggest that, while weather …

This study examined the relationships between family structure (organization and control), family process (cohesion, expressiveness, and conflict) with parenting sense of competency (parenting efficacy) for mothers (n = 138) engaged in Home Instruction for Parents of Preschool Youngsters (HIPPY) related activities. Family structure in this study looked at how the family system is organized regarding clarity of family rules. In addition, family processes of the research participants looked at daily family routines and interactions. General parenting self-efficacy, task-specific self-efficacy for nurturance, and task-specific self-efficacy for teaching which are the dependent variables, looked at the degree to which parents feel competent and capable of solving problems related to these processes in the parent-child relationship. Research questions were answered using multivariate analysis of canonical correlational analysis (CCA) to examine the associations between the independent and dependent variables. Results showed significant relationship between family structure variables of control and organization and parents' self-report of their general efficacy and their task specific efficacy for teaching and nurturing. The study also showed an inverse relationship between process variable of conflict and overall self-efficacy of parents' and their task specific efficacy for teaching and nurturing.

This dissertation explores both the production of underclass literature and the vibrancy of material between 1868-1935. During an era of rampant materialism, consumer capitalism, unchecked industrialism, and economic inequality in the United States, poor, working class Americans confronted their socioeconomic status by abandoning the linear framework of capitalism that draws only a straight line between market and consumer, and engaging in a more intimate relationship with local, material things – found, won, or inherited – that offered a sense of autonomy, belonging, and success. The physical seizure of property/power facilitated both men and women with the ability to recognize their own empowerment (both as individuals and as a community) and ultimately resist their marginalization by leveling access to opportunity and acquiring or creating personal assets that could be generationally transferred as affirmation of their family's power and control over circumstance. Reading into these personal possessions helps us understand the physical and psychological conflicts present amongst the underclasses as represented in American literature, and these conflicts give rise to new dynamics of belonging as invested in the transformative experience of ownership and exchange. If we can understand these discarded, poor, and foreign things and people as possessing dynamic and vibrant agency, …

The purpose of this quantitative secondary data analysis was to examine the effect of family, school, and community context on high schools whose students participate in financial aid preparation services. Data from the High School Longitudinal Study of 2009 were analyzed to answer the two research questions using Perna's conceptual model of college enrollment behaviors that explores how students gain and utilize information about financial aid and college prices. Descriptive statistics were used to determine the extent of high school participation in financial aid services. The results indicated a varying degree of these interventions being offered at high schools ranging from 22% to 52%. Schools sending students reminders of FAFSA deadlines (52%) and disseminating flyers/pamphlets on financial aid (50%) were the only two interventions that had a slight majority of schools participating. Multiple regression was used to determine if a relationship existed between the outcome variable (participation in financial aid preparation services) and several family context and school context predictor variables for eight financial aid interventions. Results revealed school context variables as the best predictors of the outcome variable. Counselor caseload and school control were the most effective in predicting high school participation in the eight financial aid preparation services, …

This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect only Ag ions is an important first step to solving the toxicity mystery of AgNPs. Chapter 3 focuses on the development of sensor coatings containing a Eu(III) based luminescent system for sensing dissolved CO2 without the aid of an absorption-based dye. It is well-known that monitoring CO2 levels in our environment is important since even at low concentrations it can cause adverse health effects to the human body. This work demonstrates a pH-sensitive Eu complex being used directly as a CO2 sensor without the aid of any other absorption-based dye. Chapter 4 explores the idea of developing a heavy metal sensor for lead and its ability to detect lead in wide concentration range upon changing the pH of the medium and the …

This work discusses the C-H bond activation by transition metal complexes using various computational methods. First, we performed a DFT study of oxidative addition of methane to Ta(OC2H4)3A (where A may act as an ancillary ligand) to understand how A may affect the propensity of the complex to undergo oxidative addition. Among the A groups studied, they can be a Lewis acid (B or Al), a saturated, electron-precise moiety (CH or SiH), a σ-donor (N), or a σ-donor/π-acid (P). By varying A, we seek to understand how changing the electronic properties of A can affect the kinetics and thermodynamics of methane C–H activation by these complexes. For all A, the TS with H trans to A is favored kinetically over TS with CH3 trans to A. Upon moving from electron-deficient to electron-rich moieties (P and N), the computed C–H activation barrier for the kinetic product decreases significantly. Thus, changing A greatly influences the barrier for methane C–H oxidative addition by these complexes. Secondly, a computational study of oxidative addition (OA) of methane to M(OC2H4)3A (M = Ta, Re and A = ancillary ligand) was carried out using various computational methods. The purpose of this study was to understand how variation …

The goal of my study is to develop a mobile application to enable all visitors, including blind and low-vision visitors, to autonomously gather and share information about interpretations of art and to have a fully independent museum-going experience. With an application, blind visitors have more access to opportunities and tools in the museum, which empowers their museum experience. My study used a qualitative, mixed-methods approach to research how blind and low vision museum visitors might increase their independence in the museum space and discover ways to equalize their access without relying on museum educators. In carrying out my study, I conducted interviews and collected data based on observations and transcribed and analyzed them using a grounded theory approach. I used Freire's theory of pedagogy of the oppressed and hooks' theory of education as the practice of freedom to frame my study.

Empirical research has shown a relationship between the school principal's leadership ability as an instructional leader and student learning outcomes. It would be reasonable to assume that the school principal benefits greatly from his or her superintendent sharing his or her knowledge and experience. The purpose of this study was to examine the perceptions of a sample of rural West Texas principals and the frequency and extent to which their superintendent provides them effective professional development and advice on a professional level or setting. Furthermore, the study focused on passive-avoidant, transactional, and transformational leadership styles. This was a mixed-method study utilizing 50 quantitative questions and 7 open-ended qualitative questions. Findings indicate that the principals'' perceptions of their superintendent's leadership style were on average, positive. Research supports that the behavior and actions superintendents used were both transformational and transactional forms of leadership and more often than not encouraged growth and positive outcomes among principals. The principals' perceptions regarding the impact of their superintendent's leadership style(s) on their own professional growth was positive, with results indicating that many superintendents would support and encourage professional and personal growth even where resources were limited.

Transhumanism is the name given to the cultural and philosophical movement which advocates radical human technological enhancement. In what follows, I use perspectives drawn from existential philosophy to problematize transhumanists' desire to recast human finitude as a series of technical problems with technical solutions. The ontological account of transhumanism offered here questions the assumed benefit and inevitability across six chapters. Following an introductory chapter, Chapter 2 introduces the key players, and present the philosophy of transhumanism and the opposing view of bioconservativism. Chapter 3 offers a narrative of transhumanism beginning with its mythical antecedents, and proceeds to describe the emergence of contemporary transhumanist institutions. Chapter 4 focuses on the challenge that transhumanists Aubrey de Grey and Ray Kurzweil present to mortality. The chapter asks whether human immortality is a coherent idea, and consider the consequences of achieving a data-driven amortality. Chapter 5 continues the analysis of transhumanism as it challenges limits to knowledge (ignorance), and limits to well-being (suffering). Ray Kurzweil is presented as a key figure of transhumanist thought, along with David Pearce, who desires to eradicate suffering through genetic engineering. The hubris of transhumanism is viewed through the lens of Friedrich Nietzsche in chapter 6. Nietzsche's critique of …

Although Hispanics are graduating from high school at greater rates, it is not leading to college success as college graduation rates remain low. In Texas, the Hispanic population has grown to the point that one out of three of all Texans are Hispanic. A phenomenological approach to research was used to investigate the perceptions of Hispanic college students on how well their public high school prepared them for college. Through face-to-face interviews and focus group discussions, eight Hispanic college students provided insight concerning their high school experience and how it translated into college readiness. Four questions guided the study: 1) in what ways do Hispanic college students believe their public high school prepared or failed to prepare them academically for post-secondary education; 2) in what ways do Hispanic college students believe their public high school prepared or failed to prepare them culturally for post-secondary education; 3) in what ways do Hispanic college students believe their public high school prepared or failed to prepare them socio-emotionally for post-secondary education; and 4) how do Hispanic students perceive their cultural identity in regards to their high school experience. Findings revealed four themes relating to how Hispanic students perceive their high school experience prepared …

Internet of Things (IoT) is a promising technology with great potential for individuals, society, governments, and the economy. IoT is expected to become ubiquitous and influence every aspect of everyday experience. Thus, IoT represents an important phenomena for both organizational and behavioral information system (IS) researchers. This dissertation seeks to contribute to IS research by studying the aspects that influence IoT adoption and use at both consumer and organizational levels. This dissertation achieves this purpose in a series of three essays. The first essay focuses on IoT acceptance in the context of smart home. The second essay focuses on examining the effect of artificial intelligence (AI) capabilities on consumers' IoT perceptions and intentions. Finally, the third essay focuses on the organizational investment and adoption of IoT technologies.

This study explored undergraduate and graduate students' attitudes toward the pleasurability of educational gamification in online learning environments. The study is a sequential explanatory mixed-methods research that investigated students' attitudes quantitatively, then qualitatively. In the quantitative phase, an online survey, the Pleasurable Learning Experiences scale (PLLEXs), was administrated at one of the largest public southwestern universities in the U.S. (N = 119). The qualitative phase involved conducting eight semi-structured interviews with selected participants. The PLLEXs uses a 4-point Likert scale that encompasses 4 subscales: (a) Preferences for Instructions, (b) Preferences for Instructors' Teaching Styles, (c) Preferences for Activities, and (d) Preferences for Learning Effectiveness. A series of analyses of variances (ANOVAs) were used to identify predictors of students' overall attitudes toward educational gamification. The main findings were: (a) students had strong preferences toward educational gamification with Preferences of Instructions rated the highest subscale and Preferences for Activities rated the lowest subscale, (b) major was a statistically significant predictor of students' attitudes toward educational gamification, (c) international students had statistically significant lower preferences toward educational gamification compared with U.S. domestic students, (c) online learning experiences measured by the number of previous online courses and the number of hours spent weekly on …

This dissertation presents a data-driven computational epidemic framework to simulate disease epidemics at global mass gatherings. The annual Muslim pilgrimage to Makkah, Saudi Arabia is used to demonstrate the simulation and analysis of various disease transmission scenarios throughout the different stages of the event from the arrival to the departure of international participants. The proposed agent-based epidemic model efficiently captures the demographic, spatial, and temporal heterogeneity at each stage of the global event of Hajj. Experimental results indicate the substantial impact of the demographic and mobility patterns of the heterogeneous population of pilgrims on the progression of the disease spread in the different stages of Hajj. In addition, these simulations suggest that the differences in the spatial and temporal settings in each stage can significantly affect the dynamic of the disease. Finally, the epidemic simulations conducted at the different stages in this dissertation illustrate the impact of the differences between the duration of each stage in the event and the length of the infectious and latent periods. This research contributes to a better understanding of epidemic modeling in the context of global mass gatherings to predict the risk of disease pandemics caused by associated international travel. The computational modeling and …

The growing commercialism within Division I big-time athletics has raised the financial stakes for universities, as successful athletic programs benefit from increased opportunities for financial gain. This has contributed to a pervasive "win culture" that drives institutions to seek competitive advantages, and as a side effect, NCAA rule violations have become incentivized. Programs whose infractions go unnoticed may benefit from the competitive advantage gained, but for programs investigated by the NCAA, the financial penalties incurred may far outweigh the potential revenues from undetected violations. The purpose of this study was to address institutional self-sanctions as an organizational behavior in response to NCAA major infractions and the impact of self-sanctioning on alumni charitable giving. Through the use of neo-institutional and resource dependence theories, this study aimed to further examine the role of institutional self-sanctions as a crisis management strategy in containing financial fallout of athletic scandal. While researchers have addressed scandal and alumni charitable giving in relation to athletics and institutional self-sanctions, respectively, no research exists linking the two bodies of literature. This study employed a two-way fixed effects analysis of 10 years of panel data to address the effect of key variables on alumni charitable giving. Analysis results indicated no …

This dissertation investigates the interrelationships between a client's non-GAAP earnings disclosures, financial health (profit and loss status), and the external auditor's assessment of the client's going concern status. This dissertation comprises two essays. Essay 1 examines the informativeness and the quality of non-GAAP earnings disclosures in profit and loss firms separately. Using a large sample of non-GAAP earnings voluntarily disclosed by managers, I find that the informativeness and the quality of non-GAAP earnings vary in firms cross-classified by GAAP loss status and non-GAAP loss status. I also find that loss firms have higher quality non-GAAP exclusions relative to profit firms, although the expenses excluded by both profit and loss firms are associated with firms' future performance. Further, I posit and find that profit firms which voluntarily disclose non-GAAP losses have high-quality exclusions, while other non-GAAP reporting profit firms have low-quality exclusions. Having found that non-GAAP earnings in loss firms is opportunistic to some extent, I next study, in Essay 2, whether auditors understand the implications of low-quality non-GAAP reporting in these firms. Specifically, I examine 1) whether non-GAAP earnings disclosures are associated with the propensity of the auditor's going concern issuance to loss firms, and 2) whether non-GAAP earnings disclosures …

Relational trust exists between and among individuals within complex human organizations; however, within a school, the relationship between teachers and the principal is at the heart of the organization. The purpose of this mixed method study was to gain an understanding of the relationship between teachers' trust in their principal and teacher efficacy and determine which leadership behaviors and facets of trust have the greatest influence on the trust relationship between teachers and the principal. The overarching goal of this dissertation study was to inform district-level administrators and principals so they are afforded the opportunity to reflect on their behavior, make changes if necessary to cultivate trusting relationships within their organization, and positively influence teacher efficacy. A convergent parallel mixed methods research study was conducted in two rural school districts in North Texas to identify teacher perceptions related to the leadership behaviors that influence organizational trust, and reveal the correlation between trust in the principal and teacher efficacy. The teachers who participated in the on-line survey named communication as the leadership behavior most closely related to their feelings of trust toward the principal. The facet of trust considered most significant by all teachers was reliability; however, a subset of high …

A collection of interconnected short stories set in diverse corners of Texas, converging on Galveston Island before and after Hurricane Ike.

Online learning is no longer considered novel within higher education. It has emerged as an accepted distinct channel and environment for instructional engagement. There is a notable deficit of works and theoretical constructs specifically addressing the identification and differentiation of online learner types and examining them as a distinct system within the learning environment. Learning effectiveness within an online instructional environment is affected by the individual student engaged in the instruction. The instructional experience of the learner is determined by their individual perceptions of and reactions to both internal and external factors. Therefore, it is critical to address the online learner holistically as a stand-alone systemic dimension of the online learning environment to truly understand their differentiating behaviors, motives, characteristics, and dynamics. The study classified and articulated the distinctive types of learners engaged in online instruction within the higher education context based on the key dynamics, factors, and influencers of the individual in order to provide a more comprehensive understanding of the individuals engaged in learning. Additionally, the study generated a new theoretical model, the taxonomy of online learner types (TOLT) to provide unique insights into the different types of learners and serve as an essential step towards developing awareness …

In my dissertation, I elaborate on the work that I have done to extract temporally-anchored spatial knowledge from text, including both intra- and inter-sentential knowledge. I also detail multiple approaches to infer spatial timeline of a person from biographies and social media. I present and analyze two strategies to annotate information regarding whether a given entity is or is not located at some location, and for how long with respect to an event. Specifically, I leverage semantic roles or syntactic dependencies to generate potential spatial knowledge and then crowdsource annotations to validate the potential knowledge. The resulting annotations indicate how long entities are or are not located somewhere, and temporally anchor this spatial information. I present an in-depth corpus analysis and experiments comparing the spatial knowledge generated by manipulating roles or dependencies. In my work, I also explore research methodologies that go beyond single sentences and extract spatio-temporal information from text. Spatial timelines refer to a chronological order of locations where a target person is or is not located. I present corpus and experiments to extract spatial timelines from Wikipedia biographies. I present my work on determining locations and the order in which they are actually visited by a person …

Integrating digital pedagogy into instruction in a manner that promotes critical thinking and drives increased student achievement and engagement in all classrooms is a goal of many campuses and districts that invest heavily in hardware, software, and professional development on an annual basis. Digital pedagogy goals tend to center around preparing students for the 21st century workforce, promoting instruction that is more engaging, and providing deeper learning for all students; however, achieving these goals is not possible without teachers willing and able to effectively implement instructional technology into the content they are teaching. The conceptual framework consists of digital leadership, teacher engagement, and resources and supports. This case study focused on the district-wide integration of technology into instruction through the elements found in the conceptual framework. Educators, from kindergarten through twelfth grade were surveyed about their attitudes, self-efficacy perceptions and willingness to integrate digital pedagogies into their current teaching practices. The online survey that utilized Likert-like scales to gather demographic information as well educator perceptions on digital integration, teaching philosophy, digital self-efficacy, and leadership's focus and expectations regarding instructional technology. Additional data, from a variety of district documents, was also gathered on leadership, professional development, and infrastructure supports utilized to …

This manuscript includes an investigation of decision making in alternative modes of transportation in order to understand consumers' decision in different contexts. In essay 1 of this study, the motives for participation in situated ridesharing is investigated. The study proposes a theoretical model that includes economic benefits, time benefits, transportation anxiety, trust, and reciprocity either as direct antecedents of ridesharing participation intention, or mediated through attitude towards ridesharing. Essay 2 of this study, focuses on self-driving vehicles as one of the recent innovations in transportation industry. Using a survey approach, the study develops a conceptual model of consumers' anticipated motives. Both essays use partial least square- structural equation modeling for assessing the proposed theoretical models.