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Characterization of Triclocarban, Methyl- Triclosan, and Triclosan in Water, Sediment, and Corbicula Fluminea (Müller, 1774) Using Laboratory, in Situ, and Field Assessments

Characterization of Triclocarban, Methyl- Triclosan, and Triclosan in Water, Sediment, and Corbicula Fluminea (Müller, 1774) Using Laboratory, in Situ, and Field Assessments

Date: May 2011
Creator: Edziyie, Regina E.
Description: In the last decade emerging contaminants research has intensified in a bid to answer questions about fate, transport, and effects as these chemicals as they get released into the environment. The chemicals of interest were the antimicrobials; triclocarban (TCC) and triclosan (TCS), and a metabolite of triclosan, methyl triclosan (MTCS). This research was designed to answer the question: what is the fate of these chemicals once they are released from the waste water treatment plant into receiving streams. Three different assessment methods; field monitoring, in-situ experiments, and laboratory studies were used to answer the overall question. TCS, TCC, and MTCS levels were measured in surface water, sediment and the Asiatic clam Corbicula fluminea. Field studies were conducted using four sites at Pecan Creek, Denton TX. Levels of all three chemicals in clams were up to fives orders of magnitude the water concentrations but an order of magnitude lower than in sediment. Highest sediment levels of chemicals were measured in samples from the mouth of Pecan Creek (highest organic matter). TCC was the most and TCS was the least accumulated chemicals. In-situ and lab studies both indicated that uptake of these chemicals into the clams was very rapid and measurable within ...
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Examining Curvilinearity and Moderation in the Relationship between the Degree of Relatedness of Individual Diversification Actions and Firm Performance

Examining Curvilinearity and Moderation in the Relationship between the Degree of Relatedness of Individual Diversification Actions and Firm Performance

Date: May 2011
Creator: Cernas Ortiz, Daniel Arturo
Description: Corporate diversification continues to be an important phenomenon in the modern business world. More than thirty years of research on diversification suggests that the degree of relatedness among a firm's business units is a factor that can affect firm performance, but the true effect of diversification relatedness on firm performance is still inconclusive. The purpose of this dissertation is to shed more light on this inconclusive association. However, attention is focused on the performance implications of individual diversification actions (e.g., acquisitions and joint ventures) rather than on the overall performance of firms with different levels of diversification. A non-experimental, longitudinal analysis of secondary data was conducted on over 450 unique acquisitions and on more than 210 joint ventures. Results suggest that even when individual diversification actions rather than entire business portfolios are examined, an inverted curvilinear association between diversification relatedness and performance is likely to emerge. This pattern is observed in both acquisitions and joint ventures. However, the association between diversification relatedness and performance in acquisitions is moderated by the level of industry adversity, though factors such as corporate coherence and heterogeneous experience do not moderate the association between diversification relatedness and performance. This study augments the body of knowledge ...
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Recommended Modified zone Method Correction Factor for Determining R-values of Cold-Formed Steel Wall Assemblies

Recommended Modified zone Method Correction Factor for Determining R-values of Cold-Formed Steel Wall Assemblies

Date: May 2011
Creator: Black, John
Description: Currently, ASHRAE has determined the zone method and modified zone method are appropriate calculation methods for materials with a high difference in conductivity, such as cold-formed steel (CFS) walls. Because there is currently no standard U-Factor calculation method for CFS walls, designers and code officials alike tend to resort to the zone method. However, the zone method is restricted to larger span assemblies because the zone factor coefficient is 2.0. This tends to overestimate the amount of surface area influenced by CFS. The modified zone method is restricted to C-shaped stud, clear wall assemblies with framing factors between 9 and 15%. The objective of the research is to narrow the gap of knowledge by re-examining the modified zone method in order to more accurately determine R-Values and U-Factors for CFS wall assemblies with whole wall framing factor percentages of 22% and above.
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Dream of a Thousand Keys: A Concerto for Piano and Orchestra

Dream of a Thousand Keys: A Concerto for Piano and Orchestra

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Date: May 2011
Creator: Choi, Da Jeong
Description: Dream of a Thousand Keys is a concerto for piano and orchestra, which consists of four movements presenting multiple dimensional meanings as suggested by the word "key." I trace the derivation of Korean traditional rhythmic cycles and numerical sequences, such as the Fibonacci series, that are used throughout the work, and explore the significant role of space between the soloist and piano that are emphasized in a theatrical aspect of the composition. The essay addresses the question of musical contrasts, similarities, and metamorphosis. Lastly, I cover terms and concepts of significant 21st-century compositional techniques that come into play in the analysis of this work.
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Re-Branding Palliative Care: Assessing Effects of a Name Change on Physician Communicative Processes During Referrals

Re-Branding Palliative Care: Assessing Effects of a Name Change on Physician Communicative Processes During Referrals

Date: May 2011
Creator: Burt, Stephanie
Description: Although provision of palliative care on the United States is growing, referrals to the service are often late or non-existent. The simultaneous care model provides a blueprint for the most progressive form of palliative care, which is palliation and disease-oriented treatments delivered concurrently. Research indicates the existence of a widespread misconception that associates palliative care with imminent death, and some organizations have chosen to re-brand their palliative care services to influence this perception. The goal of this study was to assess the effects of a name change from palliative care to supportive care on the communicative process during referrals to the service.
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Factors Associated with Risky Sexual Behavior Among Homeless Youth

Factors Associated with Risky Sexual Behavior Among Homeless Youth

Date: May 2011
Creator: Cooksey, Christy
Description: Homeless youth face numerous risks. Data on 602 homeless youth from the Midwest Homeless and Runaway Study and binary logistic regression were used to identify factors associated with their participation in risky sexual behaviors. Specifically, the effects of abuse/neglect and three potential moderating resiliency indicators, namely self-esteem, parental warmth, and parental monitoring, on having sex before adulthood and thinking about trading sex for food or shelter were examined. While none of the three resiliency indicators had the hypothesized moderating effects, controlling for abuse/neglect and various sociodemographic characteristics, parental monitoring had a direct, negative effect on having sex before adulthood, and self-esteem and parental warmth had direct, negative effects on thinking about trading sex for food or shelter. Policy implications of the findings are discussed.
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Parent-Toddler Training:  The Merits of Further Analysis

Parent-Toddler Training: The Merits of Further Analysis

Date: May 2011
Creator: Cermak, Samantha Marie
Description: Earlier identification of autism allows for interventions to begin during toddlerhood. Literature suggests that parents are an important part of very early intervention and specific goals have indicated that they are important to progress. The use of telemedicine may increase access to interventions. The purpose of the study was to evaluate a parent-toddler training program that targeted social-communication skills and incorporated a telemedicine component. Measures included parent teaching targets, child attending, vocal requesting, and coordinated joint attention and the parent's response to coordinated joint attention. Results indicate that parent teaching increased, child attending and vocalizations increased, child coordinated joint attention increased, and the parent's response to coordinated joint attention was primarily social in nature. Analysis of the home observations indicates that direct in home observations or teleconference observations neither under or overestimated behaviors. The results are discussed in the context of teaching and feedback delivery and selection of teaching targets.
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Mechanisms Affecting Bench Press Throw Performance while Using a Counter-Balanced Smith Machine

Mechanisms Affecting Bench Press Throw Performance while Using a Counter-Balanced Smith Machine

Date: May 2011
Creator: Buddhadev, Harsh
Description: The use of a counter-balance weight system of a Smith machine affects measures of bench press throw performance. Twenty-four men performed bench press throws at 30% of their one-repetition maximum under four different conditions: 1) counter-balance and rebound movement (RC), 2) no counter-balance and rebound movement (RNC), 3) counter-balance and concentric only movement (CC), and 4) no counter-balance and concentric only movement (CNC). Peak power, force, and concentric and eccentric velocities were measured using a linear accelerometer; and peak ground reaction force (GRF) was measured using a forceplate. Peak measures for concentric and eccentric velocities showed that NCB> CB and RBT > CBT. Peak GRF measures showed CB > NCB and RBT > CBT. The lower performance measures for CB were likely due to an increase in the net external load when the barbell accelerates faster than the gravitational constant causing the counter-balance weight becomes ineffective.
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Phase Separation and Second Phase Precipitation in Beta Titanium Alloys

Phase Separation and Second Phase Precipitation in Beta Titanium Alloys

Date: May 2011
Creator: Devaraj, Arun
Description: The current understanding of the atomic scale phenomenon associated with the influence of beta phase instabilities on the evolution of microstructure in titanium alloys is limited due to their complex nature. Such beta phase instabilities include phase separation and precipitation of nano-scale omega and alpha phases in the beta matrix. The initial part of the present study focuses on omega precipitation within the beta matrix of model binary titanium molybdenum (Ti-Mo) alloys. Direct atomic scale observation of pre-transition omega-like embryos in quenched alloys, using aberration-corrected high resolution scanning transmission electron microscopy and atom probe tomography (APT) was compared and contrasted with the results of first principles computations performed using the Vienna ab initio simulation package (VASP) to present a novel mechanism of these special class of phase transformation. Thereafter the beta phase separation and subsequent alpha phase nucleation in a Ti-Mo-Al ternary alloy was investigated by coupling in-situ high energy synchrotron x-ray diffraction with ex-situ characterization studies performed using aberration corrected transmission electron microscopy and APT to develop a deeper understanding of the mechanism of transformation. Subsequently the formation of the omega phase in the presence of simultaneous development of compositional phase separation within the beta matrix phase of a ...
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Modeling Student Perception of Web 2.0 Technologies Adoption in Kuwait

Modeling Student Perception of Web 2.0 Technologies Adoption in Kuwait

Date: May 2011
Creator: Alajmi, Mohammad
Description: The primary focus of this dissertation was to explore students' perceptions of adopting Web 2.0 applications at the School of Basic Education (SBE) in Kuwait. Although Web 2.0 applications are becoming more popular among the digital generation, there is still no evidence of students' perceptions of adopting the innovation of Web 2.0 technologies in Kuwait. The problem this study addresses is that the current status of Web 2.0 technologies usage by academic students has remained educationally unknown in Kuwait. Therefore, there was a need to investigate the extent to which academic students in SBE are aware of and their usage of Web 2.0 technologies, as well as the factors and obstacles that affect using these technologies. Rogers' diffusion of innovation theory (DoI) is employed in this study to specify the factors that influence student perceptions of adopting Web 2.0 applications as learning tools. Data used in this dissertation was gathered via a survey instrument from 350 students at the SBE and was statistically analyzed to find out the answers of the research questions. This study identified the low rate of Web 2.0 awareness and adoption by the students. Descriptive statistical analysis, such as mean scores and standard deviation, were used ...
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