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The Artisanal Nuke

Description: Abstract not provided
Date: February 5, 2014
Creator: Dixon, M C
Partner: UNT Libraries Government Documents Department

The Value of Ties: Impact of Director Interlocks on Acquisition Premium and Post-acquisition Performance

Description: Mergers and acquisitions (M&A) evolved as alternative governance structures for firms seeking to combine resources with other firms, access larger markets, or acquire strategic assets. In spite of managers’ enthusiasm about the practice, studies show mixed results regarding post-acquisition performance of acquiring firms. The impact of acquisitions on the performance of acquiring firms has therefore remained inconclusive. A few reasons for this have been suggested and recent meta-analytic research efforts indicate that studies in M&A may have ignored variables that have significant effects on post-acquisition performance. In a bid to extend the literature on M&A and identify cogent variables that impact on acquisition performance, this dissertation draws on social network theory to advance a proposition for the value-of-ties. This was done by examining the impact of directorate interlocks on acquisitions specifically and organizational strategy in general. A non-experimental cross-sectional study of 98 interlocked directorate companies simultaneously involved in acquisitions was conducted. Several multiple regression analyses were conducted and the results obtained suggest that there is a positive linear relationship between director interlocks and post-acquisition performance and that to some extent this relationship is moderated by acquisition experience. The study also showed that director interlocks have a negative linear relationship with acquisition premium. This study complements the body of knowledge on acquisitions and network theory. It also successfully combined a multi-level approach to research on organizations and strategic management.
Date: May 2014
Creator: Lawani, Uyi
Partner: UNT Libraries

Community College Student Success in Developmental Mathematics Courses: a Comparison of Four Instructional Methods

Description: The student success rates for three developmental mathematics courses (prealgebra, elementary algebra, and intermediate algebra) taught through four instructional methods (lecture, personalized system of instruction [PSI], hybrid, and online) were examined. The sample consisted of 9,211 students enrolled in a large Texas community college from fall 2009 through spring 2011. Student success was defined as a grade of C or better. Chi-square tests were used to compare the three developmental mathematics courses success rates. Statistically significant differences in student success were found between all four methods of instruction for all three mathematics courses (prealgebra: χ2 [df = 3] = 107.90, p < 0.001; elementary algebra: χ2 [df = 3] = 88.39, p < 0.001; intermediate algebra χ2 [df = 3] = 254.18, p < 0.001). Binary logistic regression modeling was used to determine to what extent age, gender, ethnicity, residency, Pell eligibility and mode of instruction accounted for the community college students’ course success for each of the three developmental mathematics courses. For prealgebra, the independent variables of gender, race, age, residency, and mode of instruction made statistically significant contributions to the model (χ2 [df = 14, n = 1,743] = 159.196, p < .001; Nagelkerke R2 = .119), with greater success among female, White, younger, out of country students taking the course through lecture. For elementary algebra, the independent variables of race, age, residency, and mode of instruction made statistically significant contributions to the logistic regression model (χ2 [df = 14, n = 2,731] = 816.223, p < .001; Nagelkerke R2 = .358), with greater success among , younger, out of country students taking the course through lecture, hybrid or PSI. For intermediate algebra, only race and Pell eligibility made a statistically significant contribution to the logistic regression, with greater success among White, Pell-eligible students, and mode of instruction ...
Date: May 2014
Creator: Keller, Judith
Partner: UNT Libraries

Lipodystrophy, Body Image and Depression in Hiv Positive Black Women

Description: Human immunodeficiency virus (HIV) seropositive men on highly active antiretroviral therapy treatment (HAART) who experience lipodystrophy syndrome (LD), a side effect of HAART, rate themselves as more depressed than those who did not experience LD(Crane et al., 2008). Furthermore, men who rated their LD symptoms as more severe also scored higher on depression measures than men who experienced less severe symptoms. It is unknown these findings can be generalized to other groups of HIV positive individuals. The current study seeks to fill this gap in the literature by exploring the associations between LD, body image, and depressive symptoms in an archival sample of HIV positive Black women. This study aims to describe the body changes associated with HAART in a Black female sample and explore the relationships between LD, body image, depression, and quality of life. Findings supported past research indicating a correlation between depression and poor body image but did not indicate that body image quality of life moderated the relationship between perceived body changes and depression. Results expanded on the literature by indicating that perceived body changes may be more distressing to Black women with HIV than objective changes. Lastly, findings suggested that Black women may have inaccurate perceptions of their own body changes. These findings are particularly informative for healthcare workers who treat HIV+ women. It is imperative that they consider clients’ self-report as well as clinical symptoms.
Date: May 2014
Creator: Carr, Jarice N.
Partner: UNT Libraries

Increasing the Players: Expanding the Bilateral Relationship of Conflict Management

Description: This research seeks to explore the behavior of international and regional organizations within conflict management. Previous research on conflict management primarily examines UN peacekeeping as the primary actor and lumps all non-UN actors into a single category. I disaggregate this category, examining how international and regional organizations interact when deciding to establish a peace mission, coordinate a peace mission with multiple organizations, and finally, how this interaction affects the success of peace missions. I propose a collective action theoretical framework in which organizations would rather another actor undertake the burden and costs of implementing a peace mission. I find the United Nations is motivated to overcome the collective action problem through an increase in the severity of the conflict. Regional organizations are motivated to establish a peace mission as the economic and political salience of the conflict increases, increasing the possibility of the regional organization acquiring club goods for its member states. The presence of a regional hegemon within a regional organization also significantly increases the likelihood of an organization both establishing a peace mission and taking on the primary role when coordinating a joint mission. I argue this is because a regional hegemon allows the organization to more easily overcome the collective action problem between its own member states due to the presence of a privileged actor.
Date: May 2014
Creator: Stull, Emily A.
Partner: UNT Libraries

Fundamental Issues in Support Vector Machines

Description: This dissertation considers certain issues in support vector machines (SVMs), including a description of their construction, aspects of certain exponential kernels used in some SVMs, and a presentation of an algorithm that computes the necessary elements of their operation with proof of convergence. In its first section, this dissertation provides a reasonably complete description of SVMs and their theoretical basis, along with a few motivating examples and counterexamples. This section may be used as an accessible, stand-alone introduction to the subject of SVMs for the advanced undergraduate. Its second section provides a proof of the positive-definiteness of a certain useful function here called E and dened as follows: Let V be a complex inner product space. Let N be a function that maps a vector from V to its norm. Let p be a real number between 0 and 2 inclusive and for any in V , let ( be N() raised to the p-th power. Finally, let a be a positive real number. Then E() is exp(()). Although the result is not new (other proofs are known but involve deep properties of stochastic processes) this proof is accessible to advanced undergraduates with a decent grasp of linear algebra. Its final section presents an algorithm by Dr. Kallman (preprint), based on earlier Russian work by B.F. Mitchell, V.F Demyanov, and V.N. Malozemov, and proves its convergence. The section also discusses briefly architectural features of the algorithm expected to result in practical speed increases.
Date: May 2014
Creator: McWhorter, Samuel P.
Partner: UNT Libraries

Opening Doors for Excellent Maternal Health Services: Perceptions Regarding Maternal Health in Rural Tanzania

Description: The worldwide maternal mortality rate is excessive. Developing countries such as Tanzania experience the highest maternal mortality rates. The continued exploration of issues to create ease of access for women to quality maternal health care is a significant concern. A central strategy for reducing maternal mortality is that every birth be attended by a skilled birth attendant, therefore special attention was placed on motivations and factors that might lead to an increased utilization of health facilities. This qualitative study assessed the perceptions of local population concerning maternal health services and their recommendations for improved quality of care. The study was conducted in the Karatu District of Tanzania and gathered data through 66 in-depth interviews with participants from 20 villages. The following components were identified as essential for perceived quality care: medical professionals that demonstrate a caring attitude and share information about procedures; a supportive and nurturing environment during labor and delivery; meaningful and informative maternal health education for the entire community; promotion of men’s involvement as an essential part of the system of maternal health; knowledgeable, skilled medical staff with supplies and equipment needed for a safe delivery. By providing these elements, the community will gain trust in health facilities and staff. The alignment the maternal health services offered to the perceived expectation of quality care will create an environment for increased attendance at health facilities by the local population.
Date: May 2014
Creator: McLendon, Pamela Ann
Partner: UNT Libraries

Shall We Dance? Teaching Parents the Communication Dance to Enhance Generalized Communication in Their Children

Description: Children diagnosed with autism exhibit deficits in communication that impact their ability to control their immediate environment. Recent research on mand training has been criticized for producing a limited number of mand topographies over a long span of time with limited generalization to novel environments. There is a body of research, however, that successfully establishes larger repertoires. Training parents as change agents may mediate generalization by teaching under naturally maintaining contingencies. Additional effects of parent training may reduce parent reports of stress, increase favorable quality of parent-child interactions, and increase reports of parental self-efficacy. The current study evaluated the effects of a generalized training framework to teach parents how to target generalized mands and expand their child’s communicative topographies. The effects of the training were evaluated using a non-concurrent multiple baseline across participants and skills. Results indicated that parents were able to effectively teach their child to mand for a variety of items and events and to substantially increase the number of different mand topographies and expand the topographies the child emitted. Parents were observed to have higher overall confidence and lower overall stress following intervention. The current study builds on previous research on generalized teaching strategies for parents that are effective in teaching a variety of responses to the child.
Date: May 2014
Creator: Baker, Jacqueline R.
Partner: UNT Libraries

Investigations in the Mechanism of Carbothermal Reduction of Yttria Stabilized Zirconia for Ultra-high Temperature Ceramics Application and Its Influence on Yttria Contained in It

Description: Zirconium carbide (ZrC) is a high modulus ceramic with an ultra-high melting temperature and, consequently, is capable of withstanding extreme environments. Carbon-carbon composites (CCCs) are important structural materials in future hypersonic aircraft; however, these materials may be susceptible to degradation when exposed to elevated temperatures during extreme velocities. At speeds of exceeding Mach 5, intense heating of leading edges of the aircraft triggers rapid oxidation of carbon in CCCs resulting in degradation of the structure and probable failure. Environmental/thermal barrier coatings (EBC/TBC) are employed to protect airfoil structures from extreme conditions. Yttria stabilized zirconia (YSZ) is a well-known EBC/TBC material currently used to protect metallic turbine blades and other aerospace structures. In this work, 3 mol% YSZ has been studied as a potential EBC/TBC on CCCs. However, YSZ is an oxygen conductor and may not sufficiently slow the oxidation of the underlying CCC. Under appropriate conditions, ZrC can form at the interface between CCC and YSZ. Because ZrC is a poor oxygen ion conductor in addition to its stability at high temperatures, it can reduce the oxygen transport to the CCC and thus increase the service lifetime of the structure. This dissertation investigates the thermodynamics and kinetics of the YSZ/ZrC/CCC system and the resulting structural changes across multiple size scales. A series of experiments were conducted to understand the mechanisms and species involved in the carbothermal reduction of ZrO2 to form ZrC. 3 mol% YSZ and graphite powders were uniaxially pressed into pellets and reacted in a graphite (C) furnace. Rietveld x-ray diffraction phase quantification determined that greater fractions of ZrC were formed when carbon was the majority mobile species. These results were validated by modeling the process thermochemically and were confirmed with additional experiments. Measurements were conducted to examine the effect of carbothermal reduction on the bond lengths in ...
Date: May 2014
Creator: Sondhi, Anchal
Partner: UNT Libraries

Culture Interrupted: Assessing the Effects of the Shining Path Internal Armed Conflict in the Peruvian Highlands

Description: This study was a qualitative examination of social, economic, political, and cultural dilemmas that face Peruvian survivors of the Communist Shining Path Revolution, an internal armed conflict that cut a swath of terror and destruction during the years 1980-2000, with a reported loss of 69,000 residents either killed or considered “disappeared.” The conflict affected primarily poor, uneducated Andean campesinos and townspeople in the highland areas of the Ayacucho District. In this study, I looked closely at the responsibilities of both government and NGOs in the facilitation of readjustment during and after times of instability. In addition, specific challenges the elderly, women and campesinos face in a post-conflict world are analyzed and possible social policies are discerned that might be developed to better implement the transition to a new form of community. Ideas that emerged from this research may assist policy shapers in other less developed countries involved in similar conflicts by examining how Peru dealt with its own issues. Methodology included participant observation and interviews with long-term Ayacuchan residents who stayed-in-place during war time, along with migrants who went to live in shantytowns in more urban areas. The government-mandated Truth and Reconciliation Commission report serves as a framework as it outlined those ultimately deemed responsible and detailed what those affected may expect in the way of appropriate reparations and compensation in the future. Much emphasis is given to the emerging role of women and how ensuing shifts of gender specific cultural roles may affect familial and communal bonds in small-scale societies.
Date: May 2014
Creator: Van Wye, Kalynn Hicks
Partner: UNT Libraries

Private Affections: Miscegenation and the Literary Imagination in Israel-Palestine

Description: This study politicizes the mixed relationship in Israeli-Palestinian literature. I examine Arab-Jewish and interethnic Jewish intimacy in works by Palestinian national poet Mahmoud Darwish, canonical Israeli novelist A. B. Yehoshua, select anthologized Anglophone and translated Palestinian and Israeli poetry, and Israeli feminist writer Orly Castel-Bloom. I also examine the material cultural discourses issuing from Israel’s textile industry, in which Arabs and Jews interact. Drawing from the methodology of twentieth-century Brazilian miscegenation theorist Gilberto Freyre, I argue that mixed intimacies in the Israeli-Palestinian imaginary represent a desire to restructure a hegemonic public sphere in the same way Freyre’s Brazilian mestizo was meant to rhetorically undermine what he deemed a Western cult of uniformity. This project constitutes a threefold contribution. I offer one of the few postcolonial perspectives on Israeli literature, as it remains underrepresented in the field in comparison to its Palestinian counterparts. I also present the first sustained critique of the hetero relationship and the figure of the hybrid in Israeli-Palestinian literature, especially as I focus on its representation for political options rather than its aesthetic intrigue. Finally, I reexamine and apply Gilberto Freyre in a way that excavates him from critical interment and advocates for his global relevance.
Date: May 2014
Creator: Cohen, Hella Bloom
Partner: UNT Libraries

Dual-band Microwave Device Design

Description: This thesis presents a brief introduction to microwave components and technology. It also presents two novel dual-band designs, their analysis, topology, simulation and fabrication. In chapter 2, a novel dual-band bandpass filter using asymmetric stub-loaded stepped-impedance resonators (SLSIRs) operating at 1 and 2.6 GHz is shown. This type of design applies suitable arrangements to improve the filter’s performance. Then, in chapter 3, a novel dual-band balun (transforms unbalanced input signals to balanced output signals or vice versa) operating at 1.1 and 2 GHz with flexible frequency ratios is presented, which has more advantages in microwave applications. Then, conclusion and future works are discussed in chapter 4.
Date: May 2014
Creator: Li Shen, Andres E.
Partner: UNT Libraries

El Arquetipo Del Narco Mexicano En La Novela, El Cine, Y La Música

Description: Various groups of Mexican culture have assigned to el narco archetypical characteristics of a heroic figure in the literary, visual, and auditory arts. As a result, today’s narcocultura has expanded its tentacles to a vast array of prominent industries, such as publishing companies, the silver screen, and recording studios. El narco is no longer seen by some sectors as the outlaw that stalks our society but, instead, as a hero who fights against a hegemonic faction to reclaim his sovereignty. This thesis unites interdisciplinary observations of the narco phenomena that Mexican culture has assigned to the iconic figure of el narco. The purpose of this work is to recreate the evolutionary development through a theoretical-literary analysis of this prototype in order to better understand Mexican society’s stance on this phenomenon. Octavio Paz’s theory of the Mexican psyche, Joseph Campbell’s theory of the hero’s journey, and an interdisciplinary focus will be employed to analyze this iconic figure. In this thesis, my aim is to investigate how an ultra-conservative Mexican society evolved into a consortium that upholds the narco’s indistinct behaviors and actions. What roles do first world governments and the Mexican state play to fortify, eradicate, or control the narco phenomenon? Finally, which is the most prudent strategy to coexist in a world alongside the narco?
Date: May 2014
Creator: González, Jesús Ángel
Partner: UNT Libraries

Conjugal Rights in Flux in Medieval Poetry

Description: This study explores how four medieval poems—the Junius manuscript’s Genesis B and Christ and Satan and Geoffrey Chaucer’s Troilus and Criseyde and The Parliament of Fowls—engage with medieval conjugal rights through their depictions of agentive female protagonists. Although many laws at this time sought to suppress the rights of women, especially those of wives’, both pre- and post-conquest poets illustrate women who act as subjects, exercising legal rights. Medieval canon and common law supported a certain amount of female agency in marriage but was not consistent in its understanding of what that was. By considering the shifts in law from Anglo-Saxon and fourteenth century England in relation to wives’ rights and female consent, my project asserts that the authors of Genesis B and Christ and Satan and the late-medieval poet Chaucer position their heroines to defend legislation that supports female agency in matters of marriage. The Anglo-Saxon authors do so by conceiving of Eve’s role in the Fall and harrowing of hell as similar to the legal role of a forespeca. Through Eve’s mimesis of Satan’s rhetoric, she is able to reveal an alternate way of conceiving of the law as merciful instead of legalistic. Chaucer also engages with a woman’s position in society under the law through his representation of Criseyde’s role in her courtship with Troilus in his epic romance, Troilus and Criseyde. Chaucer disrupts his audiences’ expectations by placing Criseyde as the more agentive party in her courtship with Troilus and shows that women might hope to the most authority in marriage by withholding their consent. In his last dream vision, The Parliament of Fowls, Chaucer engages again with the importance of female consent in marriage but takes his interrogation of conjugal rights a step further by imagining an alternate legal system through Nature, a female authority ...
Date: May 2014
Creator: Ward, Jessica D.
Partner: UNT Libraries

Using Baroque Vocal Music to Introduce Horn Students to the Musical Concepts of Expression, Articulation, Phrasing, and Tempo

Description: Baroque music is an area largely neglected in the music education of young horn students and wind players in general. Baroque horn repertoire is very demanding primarily due to the range. Baroque composers wrote for horn using the uppermost register of the instrument. In this range the partials are closer together, allowing for more melodic writing. This music requires an advanced level of technique, endurance, and ability. Often this repertoire is not suitable for students until they are well into their collegiate years of study. Frequently this music is performed on descant horns. Since only a small number of middle school and high school horn students continue to play after they leave their school band programs, they many never get first hand experience performing Baroque music. Vocal students are often introduced to Baroque arias early in their training. Purcell’s songs and arias are an excellent example of the literature that young voice students use. These arias and songs can be the perfect portal to Baroque music for horn students as well. Here I have created an edition of Henry Purcell’s songs and arias for young horn students. Each aria used the text as a guide for the “affect” and its impact on tone, articulation, and phrasing. The bass line is also used as a guide for determining tempo and style. Each piece is transcribed as a solo with piano accompaniment and as a duet. The goal of this edition is to use Baroque vocal music to introduce horn students to the musical concepts of expression, articulation, phrasing, and tempo.
Date: May 2014
Creator: Winter, Angela K.
Partner: UNT Libraries

Dance: a Training Package Utilizing Videotaped Self-observation to Teach Parents to Enhance Social Interactions with Children At-risk for a Developmental Delay

Description: Previous research has demonstrated the effectiveness of programs that include a videotaped self-observation component. The self-observation protocols, however, have not been clearly specified within programs that teach and report parents’ use of general teaching strategies. The current study investigates the effects of a training package with a self-observation component to teach parents to improve teaching interactions with their children at-risk for a developmental delay using an AB design replicated across participants. Data were collected across play interactions to assess the number of parent teaching episodes, child target responses, and various parent and child relationship qualities. Relationship quality measures included parent and child affect and engagement, parent directives, parent confidence and stress, and parent and child interest. The results of this study suggest that the training package was effective in that parents engaged in higher rates of teaching, their children engaged in more desired responding, and certain aspects of the parent-child interaction were enhanced. These results are discussed in terms of the effects on the parent-child teaching interaction and implications for future use of parent self-observation techniques.
Date: May 2014
Creator: Townley-Cochran, Donna
Partner: UNT Libraries

A Study of Learning Outcomes of a Mobile Travel Application in Tourism Geographic Course

Description: Mobile technologies have been adopted into education more and more. New hardware, such as smart phones and tablets, has increased the popularity of mobile technology. There are also many applications created for the fields of education and tourism. This research chose a travel application from Taiwan to apply into a tourism geographic course at the Taiwan Hospitality and Tourism College (THTC). A quasi-experiment design was applied to this study. Two classes/groups participated in the study. One class was the treatment group which used the travel app through teaching scenarios. The other group was the contrast group which used a lecture format with handouts. Both groups were given a pre-test to determine knowledge of Danongdafu Forest Park (DFP), and Taiwan tourism geography. A post-test was administered after eight weeks of teaching activities. Post intervention scores were compared to pre-intervention scores between the two groups. The results of ANOVA showed that there was no statistically significant learning difference between the treatment group and the contrast group. A paired-sample t-test analysis revealed that after eight weeks of teaching DFP content, both groups gained significantly in knowledge. Furthermore, the learning attitudes and interviews of the treatment group students indicated positive responses utilizing m-learning in teaching scenarios. Students indicated a desire to receive m-learning opportunities for future courses.
Date: May 2014
Creator: Chou, Chen-Hsiung
Partner: UNT Libraries

The Transition Experience of Second Career Respiratory Faculty: a Phenomenological Study

Description: This phenomenological study investigated the transition experiences of clinical respiratory therapists who pursued second careers as respiratory faculty. Situated Learning Theory and Workplace Learning Theory were the frameworks for interviews with 11 second career respiratory faculty who had taught fewer than five years in baccalaureate degree programs. The goal of this study was to identify the major themes of their experiences. Thematic analysis revealed five common experiences: under-preparation, challenges, overwhelmed feelings, personal responsibilities, and rewards. The common theoretical framework for all participants was the critical need to understand their communities of practice within their organizations. From this study, respiratory department chairs and administrators may better understand the challenges and needs of clinical therapists as they transition into faculty positions. Positive experiences such as improved orientations and continued effective faculty support may promote a more rewarding and long-term practice.
Date: May 2014
Creator: Gresham, Jennifer L.
Partner: UNT Libraries

Examining the Relationship Between Persistence in Attendance in an Afterschool Program and an Early Warning Index for Dropout

Description: School districts constantly struggle to find solutions to address the high school dropout problem. Literature supports the need to identify and intervene with these students earlier and in more systemic ways. The purpose of this study was to conduct a longitudinal examination of the relationship between sustained afterschool participation and the host district’s early warning index (EWI) associated with school dropout. Data included 65,341 students participating in an urban school district’s after school program from school years 2000-2001 through 2011-2012. The district serves more than 80,000 students annually. Data represented students in Pre-Kindergarten through Grade 12, and length of participation ranged from 1 through 12 years. Results indicated that student risk increased over time and that persistent participation in afterschool programming had a significant relationship with student individual growth trajectories. Slower growth rates, as evidenced through successive models, supported students being positively impacted by program participation. Additionally, participation was more meaningful if students persisted, as noted in the lower EWI rates, as compared to students who attended less consistently.
Date: May 2014
Creator: King, Teresa C.
Partner: UNT Libraries

From Development of Semi-empirical Atomistic Potentials to Applications of Correlation Consistent Basis Sets

Description: The development of the semi-empirical atomistic potential called the embedded atom method (EAM) has allowed for the efficient modeling of solid-state environments, at a lower computational cost than afforded by density functional theory (DFT). This offers the capability of EAM to model the energetics of solid-state phases of varying coordination, including defects, such as vacancies and self-interstitials. This dissertation highlights the development and application of two EAMs: a Ti potential constructed with the multi-state modified embedded atom method (MS-MEAM), and a Ni potential constructed with the fragment Hamiltonian (FH) method. Both potentials exhibit flexibility in the description of different solid-states phases and applications. This dissertation also outlines two applications of DFT. First, a study of structure and stability for solid-state forms of NixCy (in which x and y are integers) is investigated using plane-wave DFT. A ground state phase for Ni2C is elucidated and compared to known and hypothesized forms of NixCy. Also, a set of correlation consistent basis sets, previously constructed using the B3LYP and BLYP density functionals, are studied. They are compared to the well-known to the correlation consistent basis sets that were constructed with higher-level ab initio methodologies through computations of enthalpies of formation and combustion enthalpies. The computational accuracy with regard to experiment is reported.
Date: May 2014
Creator: Gibson, Joshua S.
Partner: UNT Libraries

The Effects of Sucrose on Ethanol Consumption in Ethanol Naïve and Non-naïve Rats

Description: Sucrose fading and intermittent access are two common procedures that induce alcohol consumption in rodents. Sucrose fading procedures involve exposing ethanol naïve rats to a mixture of ethanol and sucrose and gradually reducing the concentration of sugar. Intermittent access procedures involve providing rats with access to ethanol on alternating days. Given that rats will consume ethanol without sucrose, the role of sugar in the sucrose fading procedure is unclear. Rats must be ethanol naïve when they are exposed to treatment with sucrose fading, so there is no point of comparison to show that exposure to sugar in sucrose fading produces higher levels of drinking. There has yet to be any work that isolates the effects of sugar on the consumption of alcohol. The purpose of the present experiment was to examine the effects of sucrose on ethanol consumption in rats with different alcohol histories. Two groups of six rats were exposed to two successive sucrose fading procedures, 30 days apart and their drinking was measured 30 days after each one. One group was exposed to an intermittent access procedure to establish drinking prior to treatment with sucrose fading, the other was ethanol naïve. Following sucrose fading, all rats drank pharmacologically active doses of ethanol. For both groups consumption correlated with the concentration of sucrose and decreased in a step-wise manner as it was faded. For the ethanol experienced rats, consumption dropped below baseline levels as sucrose was faded and decreased further with the second exposure. In contrast, the ethanol-naïve rats did not decrease consumption from the first sucrose fading procedure to the second. Slight differences in peak force of responses were also observed.
Date: May 2014
Creator: Dove, Rachel Jolene
Partner: UNT Libraries

Synthesis, Characterization, Structural, and Optical Properties of Zinc Oxide Nanostructures Embedded in Silicon Based Substrates

Description: Structural and optical properties of ZnO nanostructures synthesized by low energy ion implantation technique were examined. ZnO molecular ions were implanted into Si/SiO2 substrates at room temperature and then furnace annealed under different temperatures and environments. In all as-implanted samples only Zn nanostructures with varying diameters distributed into the Si/SiO2 matrices were observed. No trace of ZnO was found. The distributions of Zn nanostructures in Si/SiO2 closely matched results from Stopping and Range of Ions in Matter (SRIM) simulations. During annealing at 750 oC, Zn diffused both toward and away from the surface of the substrate and combine with oxygen to form ZnO nanostructures. At higher annealing temperatures ZnO bonding started to break down and transfer to zinc silicate (Zn2SiO4), and at 900 oC the ZnO was completely converted into Zn2SiO4. The average sizes of Zn/ZnO nanostructures depended on the ion fluence. If the fluence increased the average sizes of nanostructures also increased and vice versa. For room temperature photoluminescence (RT-PL), band-edge emission in the ultraviolet (UV) region was observed from all samples annealed at 700 oC/750 oC and were slightly blue shifted as compare to bulk ZnO. Donor-bound exciton (D,X) and acceptor-bound exciton (A,X) transitions were observed in low temperature photoluminescence (PL). The lifetime of both donor-bound excitonic emission (D, X) and acceptor-bound excitonic emission (A, X) were found to be in the picosecond (ps) range.
Date: May 2014
Creator: Pandey, Bimal
Partner: UNT Libraries

Does Underwriter Size Matter? Only Within the Right Context

Description: The initial matching relationships between underwriters and bonds/issuing firms and the certification quality of underwriters, as determined by changes in the issuing firm’s financial strength post issue, are the two primary research topics in this dissertation. Based on total underwriter syndicate market share, two distinct categories, low market power (LMP) syndicates and high market power (HMP) syndicates were defined. Firm financial strength is examined based on a new factor developed in this research. A comparison of the two underwriting categories, or pools, indicates that the HMP underwriters take on firms of lower initial financial strength and additionally, the issuing firms decline more in financial strength two years following bond issuance than do firms using LMP underwriters. Notwithstanding these results, the more interesting findings are the relationships within each of these pools. In the LMP pool of underwriters, financially stronger firms used the larger LMPs to underwrite their bonds, while the weaker firms used smaller LMPs. In contrast, among HMP underwriters, the largest HMPs aligned with the firms of relatively lower financial strength. The relationships in both pools reverse when changes in financial strength are examined. Larger LMPs are associated with greater issuing firm financial decline while larger HMPs correlate with lower levels of decline in firm financial strength. Divergent patterns in initial underwriter-issuer matching and underwriter certification found in this research indicate that there are true differences in the “small” underwriting syndicates as compared to the larger syndicates. These patterns should be considered by both issuing firms and investors as both constituencies contemplate the corporate bond market.
Date: May 2014
Creator: Kendall, Lynn K.
Partner: UNT Libraries

The Effects of Goal Difficulty and Monitoring Frequency on Effort and Risk Taking Decisions

Description: Management control systems perform a vital role in facilitating the accomplishment of organizational objectives. To effectively align the objectives of employees with those of the organization, firms balance multiple control mechanisms to encourage organizationally desired behaviors and discourage undesired behaviors. The purpose of my dissertation was two-fold. First, I assessed how changes in monitoring frequency influenced employee behaviors and the overall function of the management control system. Second, I investigated the effects of stretch goals on behavior to determine whether stretch goals can lead to harmful behaviors and whether continuous monitoring can mitigate these behaviors. Results suggest that individuals exert more effort when assigned a stretch or difficult goal compared to an easy goal. My study also finds that stretch goals can be harmful because of their effect on risk taking, goal commitment, and job insecurity. Finally, results indicate that accountability mediates the monitoring frequency-risk taking relationship such that continuous monitoring increases accountability and accountability decreases risk taking. However, the ability of monitoring frequency to decrease risk taking may depend on numerous factors. Results from this study allow practitioners to understand the potential benefits and drawbacks of implementing continuous monitoring systems and the combined effects of using these systems in conjunction with compensation systems. Consequently, this study highlights necessary considerations for practitioners during the implementation continuous monitoring systems. The study also informs practitioners of the potentially harmful effects of stretch goals, the conditions under which they occur, and the possible ways to mitigate these effects.
Date: May 2014
Creator: Shoemaker, Nikki L.
Partner: UNT Libraries