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Eight-Year Course of Cognitive Functioning in Bipolar Disorder with Psychotic Features

Description: The purpose of the current study was to examine neuropsychological functioning in patients with bipolar disorder (BD) with psychotic features. Data from a large, epidemiological study of patients with first-episode psychosis was used to examine verbal learning and working memory 10 years after onset of psychosis in patients with BD relative to patients with schizophrenia (SZ) and patients with psychotic major depressive disorder (MDD). Cross-sectional comparisons of verbal learning and working memory at the 10-year follow-up mirrored findings of relative performance at the 2-year follow-up (Mojtabai, 2000), as patients with SZ performed significantly worse than patients with psychotic affective disorders. When FEP patients' cognitive performance was examined longitudinally, all groups showed non-significant decline over time, with no significant diagnostic group differences after accounting for current symptoms. More frequent hospitalizations and longer treatment with antipsychotics were associated with poorer performance on cognitive testing 10 years after illness onset, but these associations disappeared when controlling baseline cognitive performance. Within the BD sample, current positive and negative psychotic symptoms were associated with poorer performance on cognitive testing. After controlling for baseline cognitive performance, markers of clinical course were unrelated to cognitive performance, consistent with existing literature on longitudinal cognitive functioning in patients with BD. The current findings support a neurodevelopmental model of verbal learning and working memory deficits in patients with bipolar disorder.
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Date: August 2016
Creator: Bain, Kathleen Marie

Eighteenth-Century French Oboes: A Comparative Study

Description: The oboe, which first came into being in the middle of the seventeenth century in France, underwent a number of changes throughout the following century. French instruments were influenced both by local practices and by the introduction of influences from other parts of Europe. The background of the makers of these instruments as well as the physical properties of the oboes help to illuminate the development of the instrument during this period. The examination of measurements, technical drawings, photographs, and biographical data clarify the development and dissemination of practices in oboe building throughout eighteenth-century France. This clarification provides new insight into a critical period of oboe development which has hitherto not been exclusively addressed.
Date: May 2001
Creator: Cleveland, Susannah

Eighth Grade Science Teacher Quality Variables and Student Achievement

Description: While No Child Left Behind ushered in the age of the "highly qualified" teacher, accountability focus has been shifted to the "highly effective" teacher, defined as teacher impact on student achievement. The Science Texas Assessment of Knowledge and Skills (TAKS) is used to judge the adequate yearly progress of students in Texas public schools. Therefore, the purpose of this study was to examine the relationship of teacher factors (i.e., ethnicity, gender, teaching experience, university selectivity, certification route, National Center for Education Statistics Locale/Code, number of science content and pedagogical course semester credit hours, grade point average for science content and pedagogical coursework) on student achievement using the eighth grade Science TAKS. The primary dependent variables were students' five objective scores and their overall scores on the eighth grade Science TAKS examination. The sample was 44 eighth grade science teachers and 4,119 students in Texas public schools. Multiple linear regression models enabled examinations of the relationships between teacher quality variables and student achievement. No significant relationships between the variables were found. Small effect sizes for the beta weights and structure coefficients occurred between teachers' science credit hours and TAKS objectives to explain 20% of the variance for TAKS Living Systems and the Environment, 39% of the variance for TAKS Structures and Properties of Matter, and 21% of the variance for TAKS Earth and Space Systems. Teacher experience accounted for 24% of the variance with TAKS Structures and Properties of Matter, and pedagogical credit hours explained 30% of the variance with TAKS Motion, Forces, and Energy. Science GPA explained 31% of the variance for the TAKS Earth and Space Systems objective. Policy makers should examine NCLB assumptions about teacher content knowledge as a significant indicator of teacher effectiveness via student achievement on standardized tests. While measuring content knowledge provides a simple, efficient, ...
Date: December 2010
Creator: Harp, Amy

El ékfrasis en la Poesía De Manual Machado

Description: Manuel Machado is known as one of the most innovative Spanish modernist poets of the twentieth century. Despite his recognition as a literary figure in Spain, the mimetic descriptions in Machado's poetics are interpreted as mere innovations in Spanish poetry. Those mimetic descriptions are examples of ekphrasis in Spanish literature. Ekphrasis is both a literary and representational art. The mimetic dimension in Machado's poetry is ignored or misinterpreted by the critics of his poetics. This study written in Spanish investigates the use of ekphrasis in terms of Machado's poetic style. An analysis of Manuel Machado's ekphrastic poems will determine: ekphrastic poetry is a representational art; how visual and acoustic aspects of Machado's poems create enargeia; and the manifestation of ekphrasis in Spanish verse. In using Machado's poems, this project will contribute to future explorations of ekphrasis in Spanish literature.
Date: May 2011
Creator: Carrillo, Yolanda

Elaboration and Content Analysis of Conceptual Structure in Posttraumatic Stress Disorder

Description: Three recent studies attempted to substantiate Sewell and Cromwell's (1990) theory of Posttraumatic Stress Disorder (PTSD; American Psychiatric Association, 1994) based on personal construct theory (Kelly, 1955). One crucial aspect of the model that was tested in each of the studies is "elaboration," which is the process of bringing more of a person's repertoire of understanding (constructions) to a certain experience to give it meaning. Elaboration is representative of whether or not the individual is using an integrated set of constructs to deal with a traumatic event. A two-part study (1) reanalyzed existing data to assist in understanding discrepancies in past findings, and (2) content analyzed constructs given by subjects in all three studies. Findings concerning elaboration remained somewhat discrepant but suggested possible differences when investigating the emergent versus submerged poles of constructs.
Date: August 1997
Creator: Moes-Williams, Amy J.

Elasticity of Money as a Reinforcer: Assessing Multiple Compositions of Unit Price

Description: Behavioral economics is the integration of concepts from micro-economics into behavior analysis. Most of the research in behavioral economics has been done with non-human subjects and with drugs as reinforcers. This study represents an extension of previous research to assess money as a reinforcer with humans as subjects. The participants in this study solved math problems to earn money at various unit prices. Results indicate that demand of money adhered to the law of demand in that consumption decreased as unit prices increased. An underlying assumption is that consumption should be equivalent at different compositions of unit price. Replications of either the same or different compositions of unit price indicated that there were some discrepancies in consumption in this study.
Date: December 1999
Creator: Viken, Kjetil

Elder Abuse: A Multi-Case Study

Description: This descriptive study with quantitative aspects examined the phenomenon of elder abuse through the systematic review of 60 cases of elder abuse. Cases were randomly selected from the files of an Adult Protective Services agency in the North Central Texas area. Research questions examined the characteristics of the victims and abusers, types and duration of abuse, descriptions of abusive situations, the reporting and verification of abuse, case management strategies utilized by caseworkers, and the consequences of those strategies. The results of this study point to the probability of the elderly abuse victim being 75 years of age or older, female, white, and widowed. There did appear to be some connection between race and type of abuse with white victims more likely to experience physical and financial abuse. Approximately half of the elderly abuse victims had severe limitations in physical and/or mental functioning leading to some degree of dependence upon their abusers. However, eighty percent of the elderly victims resided in their own homes and half of these individuals were functionally independent. This study provided descriptions of the various types of abuse that were observed: physical, financial, emotional, passive neglect, and active neglect. Financial abuse was noted most frequently, and multiple types of abuse were noted in most cases with the combination of physical, financial, and emotional abuse being observed most frequently. Fifteen different categories of case management strategies were examined, averaging four different assistance strategies per case. Legal services appeared to be the most often refused form of assistance. This study also found no evidence that those who abuse the elderly are being prosecuted.
Date: August 1986
Creator: Powell, Sharon L. (Sharon Leigh)

Elder Abuse: Education for Persons with Experienced Violence

Description: The rationale for this study was based on the application of the cycle of domestic violence theory to elder abuse. It examined the effect of history of experienced childhood violence on tolerance, behavioral intentions, and past behaviors of elder abuse toward general and specific elderly targets. The effectiveness of educational interventions for altering tolerance and behavioral intentions of elder abuse was examined. Two hundred and twenty-five undergraduates were assessed for aging knowledge, general aging attitudes, aging anxiety, elder abuse attitudes, and elder abuse intentions and past behaviors. Participants were assigned to a High or Low Experienced Violence group and participated in an educational group or control group. Posttest and one-month followup measures were obtained. No differences were found at pretest between High and Low Violence. Level of Violence did not impact intervention efficacy. Elder abuse education altered attitudes, intentions, and behaviors of elder abuse at posttest significantly more than did aging education or control groups (p < .001), but these effects were no longer significant at followup. Elder abuse attitudes had higher relationships with elder abuse intentions and reported past behaviors than did global aging attitudes or aging anxiety (p < .05). General elderly targets yielded more tolerance, intentions, and reported past behaviors of elder abuse than did specific elderly targets (p < .001). Experienced childhood abuse was unrelated to elder abuse expression yielding no support for the role of cycle of violence in elder abuse. Specificity of target mediated elder abuse attitudes, intentions, and behaviors. Primary prevention interventions which aim to reduce tolerance and intentions of elder abuse should include specific information on elder abuse; aging education is ineffective for this goal.
Date: August 1990
Creator: Reinberg, Julie A. (Julie Ann)

Electoral Behavior in Texas from 1944 Through 1972

Description: "This report concludes that the evidence from the analyses seems to support the following propositions in regard to Texas electoral behavior. (1) The 1956 election year was a critical election year in Texas. (2) A pattern indicative of an underlying economic liberalism-conservatism was present in Texas voting patterns from 1944 through 1956, but not after. (3) The Mexican-American and German counties experienced political realignment in 1956 which continued through 1972. (4) The counties affording the most support to the liberal faction shift continuously. (5) The Texas electorate had been in a state of flux since 1956. To date no pattern other than the ethnic group realignment has stabilized. (6) Party-competition in gubernatorial elections has been increasing since 1962. (7) Ralph Yarborough has been the only liberal candidate for a major statewide office to draw support in a high and uniform degree across the state. (8) Ralph Yarborough's base of support has completely shifted since 1952. (9) The Farenthold vote was most closely aligned with that of Donald Yarborough. (10) Socio-economic factors have stronger relationship to Republican, liberal Democratic candidates, and major third party candidates than to conservative Democratic candidates. (11) All evidence form these analyses points to personalism and candidate appeal as the most important independent variables operating in Texas elections. " --leaf [3-4].
Date: August 1973
Creator: Dickenson, Martha Kay

Electoral Rules, Political Parties, and Peace Duration in Post-conflict States

Description: This dissertation examines the following research question: Which types of electoral rules chosen in post-conflict states best promote peace? And are those effects conditional upon other factors? I argue that the effects are conditional upon the types of political parties that exist in the post-conflict environment. Although this explanation is contrary to scholars that speak of political parties as products of the electoral system, political parties often predate the choice of electoral system. Especially in post-conflict states, political parties play an important role in the negotiation process and hence in the design of the electoral rules. I argue that the effects of electoral rules on peace duration are mitigated by the degree to which a party system is broad (nonexclusive) or narrow (exclusive). I develop a theoretical model that led to three hypotheses focusing on the independent role that political parties play in mitigating the effects of electoral rules on peace duration. To test these hypotheses, I use the Cox proportional hazard model on 57 post-conflict states from 1990 to 2009 and had competitive elections. The empirical results show support for the main argument of this study. First, the findings show that electoral rules alone do not increase or decrease the risk of civil war outbreak, yet when interacting with the degree to which political parties are broad or narrow, there is a significant effect on the outbreak of civil war. Second, the results show that post-conflict states with party centered electoral systems (closed list PR system) are less likely to have an outbreak of civil war when more seats in the parliament are controlled by broad-based parties. In addition, I conduct a comparative case study analysis of two post-conflict states, Angola (1975-1992) and Mozambique (1975-1994), using the most similar systems (MSS) research design.
Date: December 2014
Creator: Kisin, Tatyana Tuba Kelman

Electoral System Effects On Anti-muslim Sentiments In Western Europe

Description: The purpose of this thesis is to answer the question, why is there a variation in anti-Muslim sentiments across Western Europe? There is existing literature on individual and country-level variable s to explain why prejudice exists, but this research examines the impact of political institutions on anti-Muslim sentiments. Based on new institutionalism theory, electoral systems can shape public attitudes by providing far-right parties a platform to put their concerns on the agenda, and these parties promote anti-Muslim popular sentiments. The results of this analysis support this argument in that the larger the average district magnitude in a country, the greater the anti-Muslim sentiments. The findings also show that an increase in far-right party vote-share also covaries with an increase in anti-Muslim sentiments.
Date: December 2011
Creator: Saleemi, Asmara

Electrical and Structure Properties of High-κ Barium Tantalite and Aluminum Oxide Interface with Zinc Oxide for Applications in Transparent Thin Film Transistors

Description: ZnO has generated interest for flexible electronics/optoelectronic applications including transparent thin film transistors (TFTs). For this application, low temperature processes that simultaneously yield good electrical conductivity and optical transparency and that are compatible with flexible substrates such as plastic, are of paramount significance. Further, gate oxides are a critical component of TFTs, and must exhibit low leakage currents and self-healing breakdown in order to ensure optimal TFTs switching performance and reliability. Thus, the objective of this work was twofold: (1) develop an understanding of the processing-structure-property relationships of ZnO and high-κ BaTa2O6 and Al2O3 (2) understand the electronic defect structure of BaTa2O6 /ZnO and Al2O3/ZnO interfaces and develop insight to how such interfaces may impact the switching characteristics (speed and switching power) of TFTs featuring these materials. Of the ZnO films grown by atomic layer deposition (ALD), pulsed laser deposition (PLD) and magnetron sputtering at 100-200 °C, the latter method exhibited the best combination of n-type electrical conductivity and optical transparency. These determinations were made using a combination of photoluminescence, photoluminescence excitation, absorption edge and Hall measurements. Metal-insulator-semiconductor devices were then fabricated with sputtered ZnO and high-κ BaTa2O6 and Al2O3 and the interfaces of high-κ BaTa2O6 and Al2O3 with ZnO were analyzed using frequency dependent C-V and G-V measurements. The insulator films were deposited at room temperature by magnetron sputtering using optimized processing conditions. Although the Al2O3 films exhibited a lower breakdown strength and catastrophic breakdown behavior compared to BaTa2O6/ZnO interface, the Al2O3/ZnO interface was characterized by more than an order of magnitude smaller density of interface traps and interface trapped charge. The BaTa2O6 films in addition were characterized by a significantly higher concentration of fixed oxide charge. The transition from accumulation to inversion in the Al2O3 MIS structure was considerably sharper, and occurred at less than one tenth of ...
Date: August 2011
Creator: Kuo, Fang-Ling

Electrical Conduction Mechanisms in the Disordered Material System P-type Hydrogenated Amorphous Silicon

Description: The electrical and optical properties of boron doped hydrogenated amorphous silicon thin films (a-Si) were investigated to determine the effect of boron and hydrogen incorporation on carrier transport. The a-Si thin films were grown by plasma enhanced chemical vapor deposition (PECVD) at various boron concentrations, hydrogen dilutions, and at differing growth temperatures. The temperature dependent conductivity generally follows the hopping conduction model. Above a critical temperature, the dominant conduction mechanism is Mott variable range hopping conductivity (M-VRH), where p = ¼, and the carrier hopping depends on energy. However, at lower temperatures, the coulomb interaction between charge carriers becomes important and Efros-Shklosvkii variable hopping (ES-VRH) conduction, where p=1/2, must be included to describe the total conductivity. To correlate changes in electrical conductivity to changes in the local crystalline order, the transverse optical (TO) and transverse acoustic (TA) modes of the Raman spectra were studied to relate changes in short- and mid-range order to the effects of growth temperature, boron, and hydrogen incorporation. With an increase of hydrogen and/or growth temperature, both short and mid-range order improve, whereas the addition of boron results in the degradation of short range order. It is seen that there is a direct correlation between the electrical conductivity and changes in the short and mid-range order resulting from the passivation of defects by hydrogen and the creation of trap states by boron. This work was done under the ARO grant W911NF-10-1-0410, William W. Clark Program Manager. The samples were provided by L-3 Communications.
Date: December 2014
Creator: Shrestha, Kiran (Engineer)

Electrical Conductivity in Thin Films

Description: This thesis deals with electrical conductivity in thin films. Classical and quantum size effects in conductivity are discussed including some experimental evidence of quantum size effects. The component conductivity along the applied electric field of a thin film in a transverse magnetic field is developed in a density matrix method.
Date: May 1973
Creator: Meyer, Frederick Otto

Electrical resistivity as a measure of change of state in substrates: Design, development and validation of a microprocessor-based system.

Description: Smart structures are relevant and significant because of their relevance to phenomena such as hazard mitigation, structural health monitoring and energy saving. Electrical resistance could potentially serve as an indicator of structural well-being or damage in the structure. To this end, the development of a microprocessor-based automated resistance measurement system with customized GUI is desired. In this research, a nodal electrical resistance acquisition circuit (NERAC) system was designed. The system hardware interfaces to a laptop, which houses a customized GUI developed using DAQFactory software. Resistance/impedance was measured using DC/AC methods with four-point probes technique, on three substrates. Baseline reading before damage was noted and compared with the resistance measured after damage. The device was calibrated and validated on three different substrates. Resistance measurements were taken from PVDF samples, composite panels and smart concrete. Results conformed to previous work done on these substrates, validating the effective working of the NERAC device.
Date: December 2009
Creator: Le, Dong D.

Electricity in Rural Areas of North Texas

Description: "This study shows three things: (1) a precedent for the expenditure of public funds to teach electricity in our public high schools has already been established by the school system in the larger school systems of Texas, (2) the rural families living on electrified farms in the North Texas area want instruction of this type given to the boys and girls in their communities, and (3) both the rural people and the professional people of the North Texas area believe that instruction dealing with the use of electricity and electrical equipment had spread until by 1935 more than twenty-one million homes, about eighty percent of the total in America at that time, were electrified, only eleven American farms out of every 100 had central-station electricity. More than five million American farms lacked electric service. "--leaf 50.
Date: January 1949
Creator: Greathouse, Charles Simmons

An Electro- Magneto-static Field for Confinement of Charged Particle Beams and Plasmas

Description: A system is presented that is capable of confining an ion beam or plasma within a region that is essentially free of applied fields. An Artificially Structured Boundary (ASB) produces a spatially periodic set of magnetic field cusps that provides charged particle confinement. Electrostatic plugging of the magnetic field cusps enhances confinement. An ASB that has a small spatial period, compared to the dimensions of a confined plasma, generates electro- magneto-static fields with a short range. An ASB-lined volume thus constructed creates an effectively field free region near its center. It is assumed that a non-neutral plasma confined within such a volume relaxes to a Maxwell-Boltzmann distribution. Space charge based confinement of a second species of charged particles is envisioned, where the second species is confined by the space charge of the first non-neutral plasma species. An electron plasma confined within an ASB-lined volume can potentially provide confinement of a positive ion beam or positive ion plasma. Experimental as well as computational results are presented in which a plasma or charged particle beam interact with the electro- magneto-static fields generated by an ASB. A theoretical model is analyzed and solved via self-consistent computational methods to determine the behavior and equilibrium conditions of a relaxed plasma. The equilibrium conditions of a relaxed two species plasma are also computed. In such a scenario, space charge based electrostatic confinement is predicted to occur where a second plasma species is confined by the space charge of the first plasma species. An experimental apparatus with cylindrical symmetry that has its interior surface lined with an ASB is presented. This system was developed by using a simulation of the electro- magneto-static fields present within the trap to guide mechanical design. The construction of the full experimental apparatus is discussed. Experimental results that show the characteristics of ...
Date: May 2014
Creator: Pacheco, Josè L.

Electrochemical Deposition of Zinc-Nickel Alloys in Alkaline Solution for Increased Corrosion Resistance.

Description: The optimal conditions for deposition of zinc-nickel alloys onto stainless steel discs in alkaline solutions have been examined. In the past cadmium has been used because it shows good corrosion protection, but other methods are being examined due to the high toxicity and environmental threats posed by its use. Zinc has been found to provide good corrosion resistance, but the corrosion resistance is greatly increased when alloyed with nickel. The concentration of nickel in the deposit has long been a debated issue, but for basic solutions a nickel concentration of 8-15% appears optimal. However, deposition of zinc-nickel alloys from acidic solutions has average nickel concentrations of 12-15%. Alkaline conditions give a more uniform deposition layer, or better metal distribution, thereby a better corrosion resistance. Although TEA (triethanolamine) is most commonly used to complex the metals in solution, in this work I examined TEA along with other complexing agents. Although alkaline solutions have been examined, most research has been done in pH &#8805; 12 solutions. However, there has been some work performed in the pH 9.3-9.5 range. This work examines different ligands in a pH 9.3-9.4 range. Direct potential plating and pulse potential plating methods are examined for optimal platings. The deposits were examined and characterized by XRD.
Date: December 2009
Creator: Conrad, Heidi A.

Electrochemical Depostion of Bismuth on Ruthenium and Ruthenium Oxide Surfaces

Description: Cyclic voltammetry experiments were performed to compare the electrodeposition characteristics of bismuth on ruthenium. Two types of electrodes were used for comparison: a Ru shot electrode (polycrystalline) and a thin film of radio-frequency sputtered Ru on a Ti/Si(100) support. Experiments were performed in 1mM Bi(NO3)3/0.5M H2SO4 with switching potentials between -0.25 and 0.55V (vs. KCl sat. Ag/AgCl) and a 20mV/s scan rate. Grazing incidence x-ray diffraction (GIXRD) determined the freshly prepared thin film electrode was hexagonally close-packed. After thermally oxidizing at 600°C for 20 minutes, the thin film adopts the tetragonal structure consistent with RuO2. a hydrated oxide film (RuOx?(H2O)y) was made by holding 1.3V on the surface of the film in H2SO4 for 60 seconds and was determined to be amorphous. Underpotential deposition of Bi was observed on the metallic surfaces and the electrochemically oxidized surface; it was not observed on the thermal oxide.
Date: May 2012
Creator: Taylor, Daniel M.