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open access

Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

Description: In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empiric… more
Date: August 2013
Creator: Fogueri, Uma
Partner: UNT Libraries
open access

Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy

Description: The accurate assessment of psychopathy constitutes a critical component of forensic assessments addressing offender populations. Among the core characteristics of psychopathy, the interpersonal component of deception and empathic deficits are prominently observed in offenders with psychopathic traits. Given the negative consequences of being classified as a psychopath, offenders may be likely to minimize their psychopathic traits. In particular, no research has investigated whether offenders… more
Date: August 2013
Creator: Robinson, Emily V.
Partner: UNT Libraries
open access

Acculturation and Feminist Endorsement on Control of Health and Health Behaviors in Hispanic Females

Description: Hispanic women are the fastest growing population in the United States. Thus, it is important to explore health disparities that affect this population and better understand potential causes. Several explanations have been proposed for disparities that exist including turning to cultural alternatives rather than conventional medicine, low numbers of health insurance enrollments among Hispanics, and acculturation. However, little attention has been given to explanations that take into account th… more
Date: August 2013
Creator: Garner, Ashley Nicole
Partner: UNT Libraries
open access

Alchemies

Description: This thesis consists of a collection of poems and a critical preface. The preface is a discussion of Elizabeth Bishop's descriptive mode, as demonstrated by three of her poems: "Sandpiper," "The Monument," and "Santarém." I argue for Bishop's descriptions as creative acts, and examine the gestures that help her make the reader aware of the shaping power she exercises.
Date: August 2013
Creator: Heffner, Christopher Daniel
Partner: UNT Libraries
open access

An Analysis of the Value-altering Effect of Motivating Operations

Description: Motivating operations (MOs) may affect behavior in two ways; A) an MO momentarily alters the frequency of behavior for which a particular consequence has served as reinforcement (evocative-effect) and B) an MO momentarily alters the behavioral effects of the relevant consequence (value-altering effect). Many studies have empirically demonstrated the evocative function of MOs, however, few if any studies have attempted to systematically manipulate and measure the value-altering effect. The focu… more
Date: August 2013
Creator: Devine, Bailey
Partner: UNT Libraries
open access

Blueline Concerto: Critical Essay

Description: The purpose of this critical essay is two-fold. First, the essay presents a detailed critical analysis of my original composition, Blueline Concerto for bass trombone and wind ensemble. Second, using Blueline Concerto, the essay presents preliminary findings of my study to develop an approach to composing that takes into account the musicians' health, specifically regarding noise induced hearing loss (NIHL). Through various hypothesized composition- and orchestral-based approaches, I test ef… more
Date: August 2013
Creator: Lamb, Christopher
Partner: UNT Libraries
open access

Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Description: Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were d… more
Date: August 2013
Creator: Woodard, Jennifer Kristin
Partner: UNT Libraries
open access

A Comparative Study of Non Linear Conjugate Gradient Methods

Description: We study the development of nonlinear conjugate gradient methods, Fletcher Reeves (FR) and Polak Ribiere (PR). FR extends the linear conjugate gradient method to nonlinear functions by incorporating two changes, for the step length αk a line search is performed and replacing the residual, rk (rk=b-Axk) by the gradient of the nonlinear objective function. The PR method is equivalent to FR method for exact line searches and when the underlying quadratic function is strongly convex. The PR method … more
Date: August 2013
Creator: Pathak, Subrat
Partner: UNT Libraries
open access

Contribution of Hurricane Ike Storm Surge Sedimentation to Long-term Aggradation of Coastal Marshes in Southeastern Texas and Southwestern Louisiana

Description: Coastal marshes and wetlands are vital natural resources that offer habitats for plants and animals, serve as ecological filtration for soil and water pollutants, and act as protection for coastlines. Fishing, both commercial and sport, has a large economic impact in the study area – the Gulf Coast between Galveston Bay, TX and Oak Grove, LA. The objective of this research was to determine the contribution of Hurricane Ike storm surge sedimentation to long-term marsh aggradation in Texas and … more
Date: August 2013
Creator: Denlinger, Emily E.
Partner: UNT Libraries
open access

Corrosion Protection of Aerospace Grade Magnesium Alloy Elektron 43™ for Use in Aircraft Cabin Interiors

Description: Magnesium alloys exhibit desirable properties for use in transportation technology. In particular, the low density and high specific strength of these alloys is of interest to the aerospace community. However, the concerns of flammability and susceptibility to corrosion have limited the use of magnesium alloys within the aircraft cabin. This work studies a magnesium alloy containing rare earth elements designed to increase resistance to ignition while lowering rate of corrosion. The microst… more
Date: August 2013
Creator: Baillio, Sarah S.
Partner: UNT Libraries
open access

Deconstructing Webern's Op 25, Drei Lieder: a Multidimensional Assessment

Description: Webern scholarship has not comprehensively examined op. 25, drei lieder. If the selection of text for op. 25 is viewed as one work in three movements they create a ternary form (A-B-A1). To show how this form is developed in the music the author creates a new analytical system based on Schoenberg's Grundgestalt which is defined by three basic ideas: symmetry, liquidation, and variation. The relationship between the voice and accompaniment and Webern's deliberate manipulation of the text is u… more
Date: August 2013
Creator: Morgeson, Paul Taylor
Partner: UNT Libraries
open access

Design and Application of Phased Array System

Description: Since its invention, phased array has been extensively applied in both military and civil areas. The applications include target detecting and tracking, space probe communication, broadcasting, human-machine interfaces, and remote sensing. Although the phased array applications show a broad range of potential market, there are some limitations of phased array's development: high cost, complex structure, narrow bandwidth, and high power consumption. Therefore, novel ideas are needed to reduce th… more
Date: August 2013
Creator: Ren, Han
Partner: UNT Libraries
open access

Developing a Collection Digitization Workflow for the Elm Fork Natural Heritage Museum

Description: Natural history collections house immense amounts of data, but the majority of data is only accessible by locating the collection label, which is usually attached to the physical specimen. This method of data retrieval is time consuming and can be very damaging to fragile specimens. Digitizing the collections is the one way to reduce the time and potential damage related to finding the collection objects. The Elm Fork Natural Heritage Museum is a natural history museum located at the University… more
Date: August 2013
Creator: Evans, Colleen R.
Partner: UNT Libraries
open access

Dislocation Dynamics Simulations of Plasticity in Cu Thin Films

Description: Strong size effects in plastic deformation of thin films have been experimentally observed, indicating non-traditional deformation mechanisms. These observations require improved understanding of the behavior of dislocation in small size materials, as they are the primary plastic deformation carrier. Dislocation dynamics (DD) is a computational method that is capable of directly simulating the motion and interaction of dislocations in crystalline materials. This provides a convenient approach t… more
Date: August 2013
Creator: Wu, Han
Partner: UNT Libraries
open access

Educating American Audiences: Claire Reis and the Development of Modern Music Institutions, 1912-1930

Description: The creation of institutions devoted to promoting and supporting modern music in the United States during the 1920s made it possible for American composers to develop an identity distinct from that of European modernists. These institutions were thus a critical part of the process of modernization that began in the United States during the early decades of the twentieth century. There is substantial scholarship on these musical institutions of modern music, such as the International Composers’ … more
Date: August 2013
Creator: Freeman, Cole
Partner: UNT Libraries
open access

Effect of Dispersed Particles and Branching on the Performance of a Medium Temperature Thermal Energy Storage System

Description: The main objective of my thesis is to develop a numerical model for small-scale thermal energy storage system and to see the effect of dispersing nano-particles and using fractal-like branching heat exchanger in phase change material for our proposed thermal energy storage system. The associated research problems investigated for phase change material (PCM) are the low thermal conductivity and low rate of heat transfer from heat transfer fluid to PCM in thermal energy storage system. In this st… more
Date: August 2013
Creator: Hasib, A. M. M. Golam
Partner: UNT Libraries
open access

The Effect of Season Performance on Male and Female Track and Field Athletes’ Self-identity

Description: Although the “self” has generally been conceptualized as relatively stable in sport-specific research, events such as deselection, injury, and career termination have been found to negatively affect athletes’ levels of identification with the athlete role. Additionally, there has been limited research regarding competitive failure and its ability to negatively affect athletes’ levels of identification with the athlete role. The purpose of the present investigation was to provide additional evid… more
Date: August 2013
Creator: Bradstreet, Tyler C.
Partner: UNT Libraries
open access

The Effects of Glyphosate Based Herbicides on Chick Embryo Development

Description: Glyphosate based herbicides are among the most widely used herbicides in the world. The purpose of this study was to determine developmental toxicity of glyphosate, the active ingredient in the common herbicide Roundup, on developing chicken embryos. Few studies have examined toxic effects of glyphosate alone versus the full compound formulations of Roundup, which include adjuvants and surfactants. Adjutants and surfactants are added to aid in solubility and absorption of glyphosate. In thi… more
Date: August 2013
Creator: Winnick, Blake Edward
Partner: UNT Libraries
open access

The Effects of Training History on Retention and Reacquisition of Stimulus Control

Description: The purpose of this experiment was to study the effects of training history on retention and re-acquisition of stimulus control of previously learned behaviors. In Phase I, two pairs of behaviors were alternately trained. Circle and touch behaviors were trained concurrently until two consecutive errorless sessions were run. Spin and down behaviors were trained together in the same manner. Probe sessions, in which all four cues were presented, were conducted each time a pair of behaviors reached… more
Date: August 2013
Creator: Tucker, Kathryn Lynn
Partner: UNT Libraries
open access

Environmental Philosophy and the Ethics of Terraforming Mars: Adding the Voices of Environmental Justice and Ecofeminism to the Ongoing Debate

Description: Questions concerning the ethics of terraforming Mars have received some attention from both philosophers and scientists during recent decades. A variety of theoretical approaches have been supplied by a number of authors, however research pursuant to this thesis has indicated at least two major blindspots in the published literature on the topic. First, a broad category of human considerations involving risks, dangers, and social, political, and economic inequalities that would likely be associ… more
Date: August 2013
Creator: French, Robert Heath
Partner: UNT Libraries
open access

Ethnogenesis and Captivity: Structuring Transatlantic Difference in the Early Republic, 1776-1823

Description: This study seeks to understand the development of early American ideas of race, religion, and gender as reflected in Indian and Barbary captivity narratives (tales of individuals taken captive by privateers in North Africa) and in plays that take American captives as their subject. Writers of both Indian and Barbary captivity narratives used racial and religious language – references to Indians and North Africans as demonic, physically monstrous, and animal – simultaneously to delineate Native… more
Date: August 2013
Creator: Siddiqi, M. Omar
Partner: UNT Libraries
open access

Examining the Role of Latitude and Differential Insolation in Asymmetrical Valley Development

Description: Valley development through erosional processes typically tends to create symmetrical valleys. Over time, water cuts through the substrate to create valleys, gorges, and canyons for which the sides are the valley are evenly sloped. However, there are anomalies to this process. Asymmetrical valleys have been well-documented even in areas of uniform substrate or little tectonic uplift. One proposed explanation for the asymmetry of these valleys is differential insolation. This may lead to diff… more
Date: August 2013
Creator: Curran, Lorna L.
Partner: UNT Libraries
open access

Exploring Fundamental Principles in the Study of Derived Relational Responding in Pigeons

Description: A persistent challenge for behaviorally-based accounts of learning has been providing an account of learning that occurs in the absence of systematically programmed contingencies of reinforcement. Symmetry, one type of emergent behavior, has been repeatedly demonstrated with humans, but has been considerably more difficult to demonstrate with non-humans. In this study, pigeons were exposed to a go/no-go procedure in which hue stimuli were presented full screen on a touchscreen monitor. Pigeons … more
Date: August 2013
Creator: Hinnenkamp, Jay Evan
Partner: UNT Libraries
open access

Female Adolescents and Death: a Qualitative Analysis

Description: The purpose of this research design is to explore the meaning of death for the female adolescent. A qualitative design was used as the method of research. Twelve participants were selected from a snowball sample ten females and two males. Four participants reported witnessing the death of an individual, five reported a moderated death experience in which they were not present but were told after the fact and three reported no significant experience with death. The study indicated relationships … more
Date: August 2013
Creator: Jackson, Wendy L.
Partner: UNT Libraries
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