Degree Level

Novel Carborane Derived Semiconducting Thin Films for Neutron Detection and Device Applications (open access)

Novel Carborane Derived Semiconducting Thin Films for Neutron Detection and Device Applications

Novel carborane (B10C2H12) and aromatic compounds (benzene, pyridine, diaminobenzene) copolymers and composite materials have been fabricated by electron beam induced cross-linking and plasma enhanced chemical vapor deposition (PECVD) respectively. Chemical and electronic structure of these materials were studied using X-ray and ultra-violet photoelectron spectroscopy (XPS and UPS). UPS suggest that the systematic tuning of electronic structure can be achieved by using different aromatic compounds as co-precursors during the deposition. Furthermore, top of valence band is composed of states from the aromatic moieties implying that states near bottom of the conduction band is derived from carborane moieties. Current- voltage (I-V) measurements on the ebeam derived B10C2HX: Diaminobenzene films suggest that these films exhibit enhanced electron hole separation life time. Enhanced electron hole separation and charge transport are critical parameters in designing better neutron voltaic devices. Recently, PECVD composite films of ortho-carborane and pyridine exhibited enhanced neutron detection efficiency even under zero bias compared to the pure ortho-carborane derived films. This enhancement is most likely due to longer electron-hole separation, better charge transport or a combination of both. The studies determining the main factors for the observed enhanced neutron detection are in progress by fabricating composite films of carborane with other aromatic …
Date: August 2015
Creator: James, Robinson
System: The UNT Digital Library
Precession Electron Diffraction Assisted Characterization of Deformation in α and α+β Titanium Alloys (open access)

Precession Electron Diffraction Assisted Characterization of Deformation in α and α+β Titanium Alloys

Ultra-fine grained materials with sub-micrometer grain size exhibit superior mechanical properties when compared with conventional fine-grained material as well as coarse-grained materials. Severe plastic deformation (SPD) techniques have been shown to be an effective way to modify the microstructure in order to improve the mechanical properties of the material. Crystalline materials require dislocations to accommodate plastic strain gradients and maintain lattice continuity. The lattice curvature exists due to the net dislocation that left behind in material during deformation. The characterization of such defects is important to understand deformation accumulation and the resulting mechanical properties of such materials. However, traditional techniques are limited. For example, the spatial resolution of EBSD is insufficient to study materials processed via SPD, while high dislocation densities make interpretations difficult using conventional diffraction contrast techniques in the TEM. A new technique, precession electron diffraction (PED) has gained recognition in the TEM community to solve the local crystallography, including both phase and orientation, of nanocrystalline structures under quasi-kinematical conditions. With the assistant of precession electron diffraction coupled ASTARÔ, the structure evolution of equal channel angular pressing processed commercial pure titanium is studied; this technique is also extended to two-phase titanium alloy (Ti-5553) to investigate the existence of …
Date: August 2015
Creator: Liu, Yue
System: The UNT Digital Library
Predictive Modeling for Persuasive Ambient Technology (open access)

Predictive Modeling for Persuasive Ambient Technology

Computer scientists are increasingly aware of the power of ubiquitous computing systems that can display information in and about the user's environment. One sub category of ubiquitous computing is persuasive ambient information systems that involve an informative display transitioning between the periphery and center of attention. The goal of this ambient technology is to produce a behavior change, implying that a display must be informative, unobtrusive, and persuasive. While a significant body of research exists on ambient technology, previous research has not fully explored the different measures to identify behavior change, evaluation techniques for linking design characteristics to visual effectiveness, nor the use of short-term goals to affect long-term behavior change. This study uses the unique context of noise-induced hearing loss (NIHL) among collegiate musicians to explore these issues through developing the MIHL Reduction Feedback System that collects real-time data, translates it into visuals for music classrooms, provides predictive outcomes for goalsetting persuasion, and provides statistical measures of behavior change.
Date: August 2015
Creator: Powell, Jason W.
System: The UNT Digital Library
First Principles Study of Metastable Beta Titanium Alloys (open access)

First Principles Study of Metastable Beta Titanium Alloys

The high temperature BCC phase (b) of titanium undergoes a martensitic transformation to HCP phase (a) upon cooling, but can be stabilized at room temperature by alloying with BCC transition metals such as Mo. There exists a metastable composition range within which the alloyed b phase separates into a + b upon equilibrium cooling but not when rapidly quenched. Compositional partitioning of the stabilizing element in as-quenched b microstructure creates nanoscale precipitates of a new simple hexagonal w phase, which considerably reduces ductility. These phase transformation reactions have been extensively studied experimentally, yet several significant questions remain: (i) The mechanism by which the alloying element stabilizes the b phase, thwarts its transformation to w, and how these processes vary as a function of the concentration of the stabilizing element is unclear. (ii) What is the atomistic mechanism responsible for the non-Arrhenius, anomalous diffusion widely observed in experiments, and how does it extend to low temperatures? How does the concentration of the stabilizing elements alter this behavior? There are many other w forming alloys that such exhibit anomalous diffusion behavior. (iii) A lack of clarity remains on whether w can transform to a -phase in the crystal bulk or if it …
Date: August 2015
Creator: Gupta, Niraj
System: The UNT Digital Library
Cognitive Performance as a Function of Sleep Disturbance in the Postpartum Period (open access)

Cognitive Performance as a Function of Sleep Disturbance in the Postpartum Period

New mothers often complain of impaired cognitive functioning, and it is well documented that women experience a significant increase in sleep disturbance after the birth of a child. Sleep disturbance has been linked to impaired cognitive performance in several populations, including commercial truck drivers, airline pilots, and medical residents, though this relationship has rarely been studied in postpartum women. In the present study 13 pregnant women and a group of 22 non-pregnant controls completed one week of actigraphy followed by a battery of neuropsychological tests and questionnaires in the last month of pregnancy (Time 1) and again at four weeks postpartum (Time 2). Pregnant women experienced significantly more objective and subjective sleep disturbance than the control group at both time points. They also demonstrated more impairment in objective, but not subjective cognitive functioning. Preliminary analyses indicated increased objective sleep fragmentation from Time 1 to Time 2 predicted decreased objective cognitive performance from Time 1 to Time 2, though small sample size limited the power of these findings. Implications for perinatal women and need for future research were discussed.
Date: August 2015
Creator: Wilkerson, Allison K.
System: The UNT Digital Library
The Effects of Instruction on the Singing Ability of Children Ages 5-11: a Meta-analysis (open access)

The Effects of Instruction on the Singing Ability of Children Ages 5-11: a Meta-analysis

The purpose of the meta-analysis was to address the varied and somewhat stratified study results within the area of singing ability and instruction by statistically summarizing the data of related studies. An analysis yielded a small overall mean effect size for instruction across 34 studies, 433 unique effects, and 5,497 participants ranging in age from 5- to 11-years old (g = 0.43). The largest overall study effect size across categorical variables included the effects of same and different discrimination techniques on mean score gains. The largest overall effect size across categorical moderator variables included research design: Pretest-posttest 1 group design. Overall mean effects by primary moderator variable ranged from trivial to moderate. Feedback yielded the largest effect regarding teaching condition, 8-year-old children yielded the largest effect regarding age, girls yielded the largest effect regarding gender, the Boardman assessment measure yielded the largest effect regarding measurement instrument, and song accuracy yielded the largest effect regarding measured task. Conclusions address implications for teaching, research pedagogy, and research practice within the field of music education.
Date: August 2015
Creator: Svec, Christina L.
System: The UNT Digital Library
Contributions to Descriptive Set Theory (open access)

Contributions to Descriptive Set Theory

In this dissertation we study closure properties of pointclasses, scales on sets of reals and the models L[T2n], which are very natural canonical inner models of ZFC. We first characterize projective-like hierarchies by their associated ordinals. This solves a conjecture of Steel and a conjecture of Kechris, Solovay, and Steel. The solution to the first conjecture allows us in particular to reprove a strong partition property result on the ordinal of a Steel pointclass and derive a new boundedness principle which could be useful in the study of the cardinal structure of L(R). We then develop new methods which produce lightface scales on certain sets of reals. The methods are inspired by Jackson’s proof of the Kechris-Martin theorem. We then generalize the Kechris-Martin Theorem to all the Π12n+1 pointclasses using Jackson’s theory of descriptions. This in turns allows us to characterize the sets of reals of a certain initial segment of the models L[T2n]. We then use this characterization and the generalization of Kechris-Martin theorem to show that the L[T2n] are unique. This generalizes previous work of Hjorth. We then characterize the L[T2n] in term of inner models theory, showing that they actually are constructible models over direct limit of …
Date: August 2015
Creator: Atmai, Rachid
System: The UNT Digital Library
Was There a Trumpet Sonata Before the Trumpet Sonata? an Investigation of Girolamo Fantini’s Trumpet Sonatas with Respect to Other Stile Moderno Solo Instrumental Sonatas (open access)

Was There a Trumpet Sonata Before the Trumpet Sonata? an Investigation of Girolamo Fantini’s Trumpet Sonatas with Respect to Other Stile Moderno Solo Instrumental Sonatas

In 1638 Girolamo Fantini wrote eight multi-sectional trumpet sonatas. This dissertation compares these sonatas with recognized stile moderno solo instrumental sonatas by Biagio Marini and Dario Castello in order to show that Fantini’s sonatas are stile moderno trumpet sonatas. This study looks at how form, texture, motivic organization, and instrumental effects function in the works of Castello, Marini, and Fantini. This comparison shows how and to what degree Fantini uses stile moderno characteristics in his works and concludes that Fantini’s sonatas are full-fledged examples of stile moderno trumpet sonatas.
Date: August 2015
Creator: Stoltzfus, Andreas M.
System: The UNT Digital Library
Racial Microaggressions: Relationship to Cardiovascular Reactivity and Affect Among Hispanic/Latinos and Non-Hispanic Whites (open access)

Racial Microaggressions: Relationship to Cardiovascular Reactivity and Affect Among Hispanic/Latinos and Non-Hispanic Whites

Racial microaggressions are a type of perceived discrimination entailing a brief pejorative message by a perpetrator, whether verbal or nonverbal, intentional or unintentional, about a target person that operates below the level of conscious awareness. Research supports a relationship between perceived discrimination and worse mental and physical health outcomes, with the literature centered mainly on non-Hispanic blacks. Less research exists on how perceived discrimination, specifically racial microaggressions, affects the mental and physical health of Hispanic/Latinos. This study examined how exposure to racial microaggressions, using an experimental design whereby a confederate delivers two types of racial microaggressions, influences affect and cardiovascular reactivity (CVR) among Hispanic/Latinos and non-Hispanic whites. Results revealed that the experience of racial microaggressions did not evoke larger and longer lasting emotional and physiological arousal among Hispanic/Latinos and non-Hispanic Whites. Future directions are discussed.
Date: August 2015
Creator: Hoar, Mariana
System: The UNT Digital Library
Foreignizing Mahler: Uri Caine’s Mahler Project As Intertraditional Musical Translation (open access)

Foreignizing Mahler: Uri Caine’s Mahler Project As Intertraditional Musical Translation

The customary way to create jazz arrangements of the Western classical canon—informally called swingin’-the-classics—adapts the original composition to jazz conventions. Uri Caine (b.1956) has devised an alternative approach, most notably in his work with compositions by Gustav Mahler. He refracts Mahler’s compositions through an eclectic array of musical performance styles while also eschewing the use of traditional jazz structures in favor of stricter adherence to formal ideas in the original score than is usual in a jazz arrangement. These elements and the manner in which Caine incorporates them in his Mahler arrangements closely parallel the practices of a translator who chooses to create a “foreignizing” literary translation. The 19th-century philosopher and translation theorist Friedrich Schleiermacher explained that in a foreignizing translation “the translator leaves the writer alone as much as possible and moves the reader toward the writer.” Foreignizing translations accentuate the otherness of the original work, approximating the foreign text’s form and syntax in the receiving language and using an uncommon, heterogeneous vocabulary. The resulting translations, which challenge readers with their frequent defiance of the conventions of the receiving linguistic culture, create literal, exaggerated readings that better convey authors’ characteristic use of their own languages for a new audience. …
Date: August 2015
Creator: Ritchie, J. Cole
System: The UNT Digital Library
Women and the Superintendency: a Study of Texas Women Superintendents (open access)

Women and the Superintendency: a Study of Texas Women Superintendents

Education remains one of the most gender imbalanced fields, with disproportionately fewer women in higher levels of leadership. Women who reach leadership positions in education experience many triumphs and tribulations during their tenures as principals, assistant superintendents, and superintendents. The experiences of these women in their various administrative levels of leadership can provide important insight into the reasons for their success as women superintendents in Texas. This research has probed the career trajectory of nine women who have successfully attained and retained superintendencies in Texas to determine what career decisions have helped them and the challenges these women have faced in their positions. A qualitative research method, open-ended interviews, yielded several findings of what women considered important in proceeding from teaching through the various levels and ending in becoming superintendents. According to nine successful women superintendents in Texas, there are specific characteristics one can bring to the table that would really make a difference: Communication, collaboration, compassion, preparedness, hard work, and passion. All nine participants overcame challenges when climbing to the higher levels of leadership in education. These women have achieved success in the superintendency, and several factors appear to have played into the success of these women who have …
Date: August 2015
Creator: Guajardo, Lesli Ann
System: The UNT Digital Library
Health-related Quality of Life and Social Engagement in Assisted Living Facilities (open access)

Health-related Quality of Life and Social Engagement in Assisted Living Facilities

This research project aims to clarify the factors that impact successful aging in Assisted Living facilities (ALFs) in Denton County, Texas. We hypothesize that social disengagement decreases physical and mental components of quality of life. This exploratory research project employed standardized questionnaires to assess residents in the following domains; HRQOL, social engagement status, level of cognition, depression, and the level of functioning. This study collected data from 75 participants living in five ALFs. The average of Physical Component Scale (PCS) and Mental Component Scale (MCS) was 35.33, and 53.62 respectively. None of the participants had five or more social contacts out of facilities, and two-third of them had two or less social contacts. On average, those participants who were more socially engaged had higher score of MCS compared with disengaged counterparts. The level of physical function significantly affects social engagement, when people with more disabilities are more likely to be socially disengaged. Social engagement and depression significantly impact MCS, when depression is a mediating factor between social engagement and mental component of quality of life. Considering the expansion in aging population in the United States within the next three decades, the demand for high quality long-term care will skyrocket consequently. …
Date: August 2015
Creator: Amini, Reza
System: The UNT Digital Library
The Full Range Advising Experience: an Assessment of College Academic Advisors’ Self-perceived Leadership Styles (open access)

The Full Range Advising Experience: an Assessment of College Academic Advisors’ Self-perceived Leadership Styles

The purpose of this quantitative, descriptive study was to identify the self-perceived leadership styles of college academic advisors and to explore the variance in the perceived leadership styles based on demographic information such as academic advising approaches, institutional type, age, years of experience, and gender. Participants were 225 college advisors from among 5,066 members of the National Academic Advising Association (NACADA) during the 2013-2014 academic year who met study criteria and whose email invitation to complete an online survey was presumably delivered, rendering a 4.44% response rate. The Multifactor Leadership Questionnaire Version 5X (MLQ 5X) with five supplemental questions was used for data collection The composite score for leadership style served as the dependent variable, and advising approach, institutional type, age, years of experience, and gender served as the independent variables for the study. Descriptive statistics, frequency distribution, and a factorial analysis of variance (ANOVA) were used for data analysis. The descriptive statistics for this study revealed that college academic advisors represent all points along the entire spectrum of the Full Range Model of Leadership continuum employing different leadership behaviors based on the situation. The descriptive data were supported by the frequency distributions per case which identified transformational leadership as …
Date: August 2015
Creator: Davis Jones, Chrissy L.
System: The UNT Digital Library
Megachurches and Economic Development: A Theoretical Understanding of Church Involvement at the Local Level (open access)

Megachurches and Economic Development: A Theoretical Understanding of Church Involvement at the Local Level

Why do megachurches participate in economic development, and who benefits from their participation? Frumkin's framework for understanding nonprofit and voluntary action and extra-role behavior are theories tested to answer these questions. My research employs a mixed-methods research design conducted in two phases. In phase one, I analyze 42 responses to an online survey to provide data about the prevalence and nature of economic development activities offered by megachurches in the Dallas-Fort Worth and Houston-Sugar Land-Baytown Metropolitan Statistical Areas. Phase two involved 23 semi-structured telephone interviews with megachurch leadership to provide data that explains the rationale for why megachurches offer economic development activities and who benefits. Evidence from this research demonstrates that megachurches are participating in economic development for reasons consistent with both demand-side and supply-side arguments. Findings also show that megachurches take on extra-role behaviors for in response to community expectations and the values of members and staff. Implications for understanding partnership decisions and collaborations between faith-based organizations and local governments are discussed.
Date: December 2015
Creator: English, Ashley E.
System: The UNT Digital Library
The Limits of Arbitrage and Stock Mispricing: Evidence from Decomposing the Market to Book Ratio (open access)

The Limits of Arbitrage and Stock Mispricing: Evidence from Decomposing the Market to Book Ratio

The purpose of this paper is to investigate the effect of the "limits of arbitrage" on securities mispricing. Specifically, I investigate the effect of the availability of substitutes and financial constraints on stock mispricing. In addition, this study investigates the difference in the limits of arbitrage, in the sense that it will lead to lower mispricing for these stocks, relative to non-S&P 500 stocks. I also examine if the lower mispricing can be attributed to their lower limits of arbitrage. Modern finance theory and efficient market hypothesis suggest that security prices, at equilibrium, should reflect their fundamental value. If the market price deviates from the intrinsic value, then a risk-free profit opportunity has emerged and arbitrageurs will eliminate mispricing and equilibrium is restored. This arbitrage process is characterized by large number of arbitrageurs which have infinite access to capital. However, a better description of reality is that there are few numbers of arbitrageurs to the extent that they are highly specialized; and they have limited access to capital. Under these condition arbitrage is no more a risk-free activity and can be limited by several factors such as arbitrage risk and transaction costs. Other factors that are discussed in the literature …
Date: December 2015
Creator: AlShammasi, Naji Mohammad
System: The UNT Digital Library
Acceptance Theories for Behavior in Conducting Research: Instructors in the Rajabhat University System, Thailand (open access)

Acceptance Theories for Behavior in Conducting Research: Instructors in the Rajabhat University System, Thailand

Responding to globalization and its effects on education and research development, the Thai government decided to push all public universities to become autonomous and establish a system of quality assurances. The establishment of quality assurances has had a large impact on many Thai instructors, especially in new public universities. Thai instructors are now forced to more focus on conducting research because the number of research publications is regarded as one of the main criteria for quality universities. The purpose of this study is to investigate the key factors, at the individual and university levels, which impact on the instructors' behavior in conducting research of the full-time instructors in the faculty of Management Science from the Rajabhat Universities in Thailand. The current study will help explain how and why the instructors accept or refuse to conduct research and provide insight into the salient factors motivating the instructors to produce more research by conducting HLM. Data were collected from 694 participants at 37 institutions via a questionnaire survey. The findings revealed that there was no difference among these 37 universities on behavior in conducting research. The key factors statistically influencing behavior in conducting research of the instructors were facilitating conditions, academic degree, …
Date: December 2015
Creator: Laksaniyanon, Benchamat
System: The UNT Digital Library
A Reexamination of the Dilution of Auditor Misstatement Risk Assessments: An Experimental Study of the Impact of Client Information Type, Workload, and PCAOB Guidance on Dilution (open access)

A Reexamination of the Dilution of Auditor Misstatement Risk Assessments: An Experimental Study of the Impact of Client Information Type, Workload, and PCAOB Guidance on Dilution

Many external parties such as investors, creditors, and regulatory agencies, use a company’s financial statements in their decision-making. In doing so, they rely on audit opinions on whether financial statements are fairly stated. However, evidence suggests that there are factors in the audit environment that influence auditor judgments. For example, nondiagnostic client information dilutes auditor judgments when compared to judgments based on diagnostic information alone, especially for less experienced auditors (Hackenbrack 1992; Hoffman and Patton 1997; Glover 1994; Shelton 1999). High time pressure conditions mitigate this effect by refocusing auditor attention toward relevant client information, therefore reducing the impact of nondiagnostic information (Glover 1994, 1997). This research study examines other common audit environment factors to determine if they too influence audit judgment results. An online questionnaire of 149 auditors, CPAs and other accounting professionals indicate that the inclusion of nondiagnostic client information results in a significant change in auditor judgments. The direction of this change follows a theorized pattern; risk assessments that were initially high are reduced, while those that were initially low are increased. Significance was not consistently found for a workload and PCAOB effect on auditor judgment. However, a comparison of the absolute value of dilution effect means …
Date: December 2015
Creator: Perry, Suzanne M.
System: The UNT Digital Library
Measuring Culture of Innovation: A Validation Study of the Innovation Quotient Instrument (open access)

Measuring Culture of Innovation: A Validation Study of the Innovation Quotient Instrument

The ability for an organization to innovate has become one of the most important capabilities needed in the new knowledge economy. The research has demonstrated that an organization’s culture of innovation in particular predicts organizational innovativeness across multiple industries. To provide support to these organizations in their abilities to understand the culture of innovation, researchers have developed instruments to measure culture of innovation, and while many of these instruments have been widely used to inform organizational opportunities for improvement, few of these instruments have been validated or replicated beyond their initial use. The current study employs multiple factor analytic methods to validate the factor structure of the Innovation Quotient instrument developed by Rao and Weintraub and assess the extent to which the instrument is reliable for multiple organizational groups. The results of this study, as well as implications for researchers interested in culture of innovation, are presented.
Date: December 2015
Creator: Danks, Shelby
System: The UNT Digital Library
Single Notch Versus Multi Notch Credit Rating Changes and the Business Cycle (open access)

Single Notch Versus Multi Notch Credit Rating Changes and the Business Cycle

Issuers’ credit ratings change by one or more notches when credit rating agencies provide new ratings. Unique to the literature, I study the influences affecting multi notch versus single notch rating upgrades and downgrades. For Standard & Poors data, I show that rating changes with multiple notches provide more information to the market than single notch rating changes. Consistent with prior literature on the business cycle, I show that investors value good news rating changes (upgrades) more in bad times (recession) and that investors value bad news rating changes (downgrades) more in good times (expansion). I model and test probit models using variables capturing the characteristics of the previous issuer’s credit rating, liquidity, solvency, profitability, and growth opportunity to determine the classification of single notch versus multi notch rating changes. The determinants of multi notch versus single notch rating changes for upgrades and downgrades differ. Business cycle influences are evident. Firms that have multi notch rating upgrades and downgrades have significantly different probit variables vis-à-vis firms that have single notch rating upgrades and downgrades. The important characteristics for determining multiple notch upgrades are a firm’s prior rating change, prior rating, cash flow, total assets and market value. The important characteristics …
Date: December 2015
Creator: Poudel, Rajeeb
System: The UNT Digital Library
Modeling the Role of Boundary Spanners-in-Practice in the Nondeterministic Model of Engineering Design Activity (open access)

Modeling the Role of Boundary Spanners-in-Practice in the Nondeterministic Model of Engineering Design Activity

Boundary spanners-in-practice are individuals who inhabit more than one social world and bring overlapping place perspectives to bear on the function(s) performed within and across each world. Different from nominated boundary spanners, they are practitioners responsible for the 'translation' of each small world's perspectives thereby increasing collaboration effectiveness to permit the small worlds to work synergistically. The literature on Knowledge Management (KM) has emphasized the organizational importance of individuals performing boundary spanning roles by resolving cross-cultural and cross-organizational knowledge system conflicts helping teams pursue common goals through creation of "joint fields" - a third dimension that is co-jointly developed between the two fields or dimensions that the boundary spanner works to bridge. The Copeland and O'Connor Nondeterministic Model of Engineering Design Activity was utilized as the foundation to develop models of communication mechanics and dynamics when multiple simultaneous interactions of the single nondeterministic user model, the BSIP and two Subject Matter Experts (SMEs), engage during design activity in the Problem-Solving Space. The Problem-Solving Space defines the path through the volumes of plausible answers or 'solution spaces' that will satisfice the problem presented to the BSIP and SMEs. Further model refinement was performed to represent expertise seeking behaviors and the physical …
Date: December 2015
Creator: Linkins, Kathy L.
System: The UNT Digital Library
Social Participation and Depression Among Elderly People in Greece (open access)

Social Participation and Depression Among Elderly People in Greece

The researcher had two objectives: first, explore how social involvement changes by age among Greek elderly, and second, examine the relationship between social involvement and depression by age among study participants, controlled for education, marital status, and gender. The researcher used data from the 2004 Survey of Health, Aging, and Retirement in Europe (SHARE) database subjecting a sample of 2,898 elderly aged 50 or older to analysis in terms of the study questions. Approximately 43% of the participants (n = 1,244) were males and 57% were females (n = 1,654). Study results showed Greek elderly participated more in religious activities and less in non-religious activities with increasing age. The study results showed the level of education did not have an effect on the level of religious or non-religious participation. Marital status could influence Greeks’ tendency to participate in religious activities, however, it did not have an effect on non-religious participation. Women are more likely to participate in religious activities than the men. The gender of the participants did not have an effect on non-religious participation. Older Greek elderly were more likely to be depressed than the younger elderly. Participation in religious activities was not shown to relate to decreasing the …
Date: December 2015
Creator: Simmons, Daniela
System: The UNT Digital Library
Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting (open access)

Indirect Fabrication of Lattice Metals with Thin Sections Using Centrifugal Casting

There is a wide range of applications for 3D printing technology with an additive manufacturing such as aerospace, automotive, marine and oil/gas, medical, consumer, electronics, building construction, and many others. There have been many pros and cons for 3D additive manufacturing. Even though 3D printing technology has many advantages: freedom to design and innovate without penalties, rapid iteration through design permutations, excellence mass customization, elimination of tolling, green manufacturing, minimal material wastes, energy efficiency, an enablement of personalized manufacturing. 3D additive manufacturing still has many disadvantages: unexpected pre- and post-processing requirement, high-end manufacturing, low speed for mass production, high thermal residual stress, and poor surface finish and dimensional accuracy, and many others. Especially, the issues for 3D additive manufacturing are on high cost for process and equipment for high-end manufacturing, low speed for mass production, high thermal residual stress, and poor surface finish and dimensional accuracy. In particular, it is relatively challenging to produce casting products with lattice or honeycomb shapes having sophisticated geometries. In spite of the scalable potential of periodic cellular metals to structural applications, the manufacturing methods of I∙AM Casting have been not actively explored nor fully understood. A few qualitative studies of I∙AM Casting has been …
Date: December 2015
Creator: Mun, Jiwon
System: The UNT Digital Library
Computational Modeling of Small Molecules (open access)

Computational Modeling of Small Molecules

Computational chemistry lies at the intersection of chemistry, physics, mathematics, and computer science, and can be used to explain the behavior of atoms and molecules, as well as to augment experiment. In this work, computational chemistry methods are used to predict structural and energetic properties of small molecules, i.e. molecules with less than 60 atoms. Different aspects of computational chemistry are examined in this work. The importance of examining the converged orbitals obtained in an electronic structure calculation is explained. The ability to more completely describe the orbital space through the extrapolation of energies obtained at increasing quality of basis set is investigated with the use of the Sapporo-nZP-2012 family of basis set. The correlation consistent Composite Approach (ccCA) is utilized to compute the enthalpies of formation of a set of molecules and the accuracy is compared with the target method, CCSD(T,FC1)/aug-cc-pCV∞Z-DK. Both methodologies are able to produce computed enthalpies of formation that are typically within 1 kcal mol-1 of reliable experiment. This demonstrates that ccCA can be used instead of much more computationally intensive methods (in terms of memory, processors, and time required for a calculation) with the expectation of similar accuracy yet at a reduced computational cost. The …
Date: December 2015
Creator: Weber, Rebecca J.
System: The UNT Digital Library
An Educational Intervention to Promote Self-management and Professional Socialization in Graduate Nurse Anesthesia Students (open access)

An Educational Intervention to Promote Self-management and Professional Socialization in Graduate Nurse Anesthesia Students

Traditionally, nurse anesthesia educators have utilized prior academic achievement to predict student success. However, research has indicated that prior academic achievement offers an inadequate assessment of student success in graduate healthcare programs with extensive clinical residencies. The educational literature has identified many non-cognitive factors, such as self-efficacy and locus of control, that may provide a more holistic prediction model of student success. An experimental study with pretest-posttest design and stratified random assignment was conducted to evaluate the effectiveness of an educational intervention to promote self-management, professional socialization, and academic achievement among first semester graduate nurse anesthesia students. Participants (N = 66) were demographically similar to the national graduate nurse anesthesia student body, though Hispanics and younger students were a little over-represented in the sample (56% female, 75.8% White, 15.2% Hispanic, 6% Other, 59% ≤ 30-years-old, 67% ≤ 3 years of ICU). The results showed that most graduate anesthesia students had strong self-management and professional socialization characteristics on admission. The results did not support the effectiveness of this educational intervention. Thus, ceiling effect may have accounted in part for statistically non-significant results regarding self-efficacy (p = .190, ω2 = .03), locus of control (p = .137, ω2 = .04), professional socialization …
Date: December 2015
Creator: Maloy, Debra A.
System: The UNT Digital Library