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Hospital Readmissions: the Need for a Coordinated Transitional Care Model: Analysis and Synthesis of Research on Medicare Policy and Interventions for the Elderly (open access)

Hospital Readmissions: the Need for a Coordinated Transitional Care Model: Analysis and Synthesis of Research on Medicare Policy and Interventions for the Elderly

The transition from hospital to home or alternate care setting is a time of vulnerability for all patients and particularly for our elders. If not handled appropriately there is a risk to our elders for readmission to the hospital environment that may decrease their overall quality of life and further compromise their health status. in addition to the individual risks associated with patient readmissions, there are societal impacts that reach far beyond our current generation of elders 65 and older. This impact may have dire implications for the future fiscal health of the next generation. a review of the current and past literature shows that there are a limited number of resources available for hospitals to use in order to comply with the new Value Based Purchasing initiatives that are being implemented by CMS regarding the reduction in readmission rates. the problem of hospital readmissions is confounded by the many processes that are available for study, from pre-hospitalization conditions and care through hospitalization, discharge, and finally to post discharge processes. While most research and literature reviews have focused on individual disease causes, there is a need to provide hospitals with a resource that outlines the available options and interventions that …
Date: May 2012
Creator: Wolfe, Laura M.
System: The UNT Digital Library
A Study of the Intent to Fully Utilize Electronic Personal Health Records in the Context of Privacy and Trust (open access)

A Study of the Intent to Fully Utilize Electronic Personal Health Records in the Context of Privacy and Trust

Government initiatives called for electronic health records for each individual healthcare consumer by 2014. the purpose of the initiatives is to provide for the common exchange of clinical information between healthcare consumers, healthcare providers, third-party payers and public healthcare officials.This exchange of healthcare information will impact the healthcare industry and enable more effective and efficient application of healthcare so that there may be a decrease in medical errors, increase in access to quality of care tools, and enhancement of decision making abilities by healthcare consumers, healthcare providers and government health agencies. an electronic personal health record (ePHR) created, managed and accessed by healthcare consumers may be the answer to fulfilling the national initiative. However, since healthcare consumers potentially are in control of their own ePHR, the healthcare consumer’s concern for privacy may be a barrier for the effective implementation of a nationwide network of ePHR. a technology acceptance model, an information boundary theory model and a trust model were integrated to analyze usage intentions of healthcare consumers of ePHR. Results indicate that healthcare consumers feel there is a perceived usefulness of ePHR; however they may not see ePHR as easy to use. Results also indicate that the perceived usefulness of …
Date: May 2012
Creator: Richards, Rhonda J.
System: The UNT Digital Library
The Affect of Mobile Performance Support Devices on Anxiety and Self-Efficacy of Hospital Float Staff (open access)

The Affect of Mobile Performance Support Devices on Anxiety and Self-Efficacy of Hospital Float Staff

Floating describes the act of staff moving from one unit to another based on the needs of the patients in a hospital. Many staff who float to different units express negative feelings, including anxiety and lack in self-efficacy. However, floating is both an economical and efficient method to use staff across the hospital, especially with current staffing shortages in the United States. This study investigated how the use of mobile performance support devices may help reduce anxiety and increase self-efficacy for those staff who float to different units. with access to multiple resources available on the mobile device, Bandura's social learning theory and self-efficacy concept set the framework through modeling, observing, and imitating others in order to reproduce certain behaviors and tasks and believe in one's capability to perform. a quantitative study incorporating the retrospective pretest-posttest design was conducted using the population of float staff, including both nurses and respiratory therapists, from Children's Medical Center of Dallas. Both the State-Trait Anxiety Inventory and General Self-Efficacy Scale, along with a basic demographic tool, were used to explore anxiety and self-efficacy in relation to the usage of mobile performance support devices. Findings can be used to impact the negative feelings of staff …
Date: May 2012
Creator: McKee, Megan Riley
System: The UNT Digital Library
Baseband Noise Suppression in Ofdm Using Kalman Filter (open access)

Baseband Noise Suppression in Ofdm Using Kalman Filter

As the technology is advances the reduced size of hardware gives rise to an additive 1/f baseband noise. This additive 1/f noise is a system noise generated due to miniaturization of hardware and affects the lower frequencies. Though 1/f noise does not show much effect in wide band channels because of its nature to affect only certain frequencies, 1/f noise becomes a prominent in OFDM communication systems where narrow band channels are used. in this thesis, I study the effects of 1/f noise on the OFDM systems and implement algorithms for estimation and suppression of the noise using Kalman filter. Suppression of the noise is achieved by subtracting the estimated noise from the received noise. I show that the performance of the system is considerably improved by applying the 1/f noise suppression.
Date: May 2012
Creator: Rodda, Lasya
System: The UNT Digital Library
Monitoring and Increasing Goal Related Instruction and Engagement in Groups of Children with Autism (open access)

Monitoring and Increasing Goal Related Instruction and Engagement in Groups of Children with Autism

A high rate of instructional engagement is important to maximize progress in early intensive behavioral interventions (EIBI). Teachers responsible for eliciting instructional engagement may need additional support to maintain high rates of engagement. Literature suggests that goal setting and feedback is effective in increasing performance. the purpose of this study was to evaluate whether goal setting and group feedback would increase engagement in instructional activities related to the children’s goals. Results indicate that goal setting and group feedback was successful in increasing engagement in instructional activities. the results are discussed in the context of engagement, staff performance, group contingencies and performance feedback.
Date: May 2012
Creator: Rossi, Kathleen Anne
System: The UNT Digital Library
Running a Family (open access)

Running a Family

This thesis contains two parts. the preface theorizes memory and examines the author’s own experience writing her identity. Part II is a memoir framed with the process of training for a marathon. the marathon acts as a narrative thread that pulls together scenes of memory from the author’s childhood which features the author running away from home on several occasions. Running a marathon and running away from home intertwine to allow the writer to draw conclusions about her life and her family.
Date: May 2012
Creator: Rowntree, Miriam R.
System: The UNT Digital Library
Are They Ready? a Multi-case Study of Traditional and Innovative Texas Teacher’s Perceptions of 21St Century Skills in Teaching and Learning (open access)

Are They Ready? a Multi-case Study of Traditional and Innovative Texas Teacher’s Perceptions of 21St Century Skills in Teaching and Learning

The 21st century is now in the second decade and the need for 21st century skills is discussed at all levels of education as necessary for student success in the future. Federal, state, and districts are addressing this need and have written technology plans to address 21st century skills needed. the purpose of this dissertation is to contribute to the knowledge of 21st century educational technology. the data includes seven recorded interviews from two separate research projects covering two models of education as teachers discuss teaching, learning, and technology. the data studied determines how educational technology perceived in the school environments has been integrated into the classrooms. the initial scripting of video interviews from two research projects began the analysis of data. Particular themes emerged in response to questions established by the two separate research projects focused on classroom, school, and district environmental arrangements that examined; teaching responsibilities and practices; student learning opportunities; and how technology is woven throughout instruction. Further exploration of themes stemmed from analysis conducted with the qualitative software program, NVivo 9. the themes discussed in this paper relate to instructor perceptions of teaching, learning, classroom procedures, and the role technology plays in each. Also noted are …
Date: May 2012
Creator: Royal, Joy
System: The UNT Digital Library
The Choral Music of Ola Gjeilo: a New Vision of the Choral Instrument in the 21St Century (open access)

The Choral Music of Ola Gjeilo: a New Vision of the Choral Instrument in the 21St Century

The choral music of Norwegian composer Ola Gjeilo (pronounced “yay-loh”) is gaining international acclaim and is widely performed and commissioned by prominent high school, university, and professional choirs. It represents a philosophical approach and vision of the choral instrument for which the conductor must have a clear understanding in order to prepare a meaningful performance. in particular, his music merges diverse musical influences, which results in a product of unique character among choral compositions in the late 20th and early 21st centuries. Gjeilo draws inspiration from a text but then uses its sonic qualities (the sounds of vowels and consonants) to create an atmosphere of sound instead of following the traditions in choral and vocal music of using musical mechanisms (melody, rhythm, and harmony) to reinforce the text poetically. This study provides an overview of Gjeilo’s background, in Chapter 1, and discusses its influence on his compositional philosophy. Chapter 2 contains musical examples from selected works, which are used to illuminate unique attributes found in Gjeilo’s music. Chapter 3 presents important implications to consider aiding choral conductors in their preparation of future performances of Gjeilo’s music.
Date: May 2012
Creator: Schmidt, Brian A., 1980-
System: The UNT Digital Library
Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX (open access)

Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX

Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the present study was to quantify Hg concentrations in birds in differing trophic levels at Caddo Lake and Lake Lewisville, TX. Results suggest that Hg concentrations may be high enough to negatively impact some bird taxa, particularly those at high trophic levels, residing at both Caddo Lake and Lake Lewisville.
Date: May 2012
Creator: Schulwitz, Sarah E.
System: The UNT Digital Library
Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping (open access)

Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping

There are over a million adopted children in the United States, which makes up over 2% of the population. in spite of the fact that the majority of children are adopted into loving and caring homes, early life trauma puts them at higher risk for developing behavioral and emotional problems than non-adopted children. Due to these issues, many adoptive parents encounter post-adoption stress. This stress is often linked to minimal education regarding short- and long-term challenges associated with adoption. the adoption agency is likely the best group for addressing challenges, yet few researchers have studied adoption agency communication and adoptive parent adjustment. in this study I examined pre-adoption communication satisfaction, post-adoption adjustment (life change and parental adjustment), and coping strategies. Hypothesis 1 questioned the relationship between adoptive parents’ pre-adoption communication satisfaction with their social workers and post-adoption family adjustment; this hypothesis was supported only for problems related to home and work life adjustment. Hypothesis 2 predicted coping strategies would mediate the relationship between communication satisfaction and family adjustment. H2 was not supported for both life change and parental adjustment. Research Questions 1a and 1b inquired about the coping strategy that had an impact on life change and parental adjustment; escape-avoidance …
Date: May 2012
Creator: Seebeck, Lara N.
System: The UNT Digital Library
Blogging and Tweens: Communication Portal to Reading Selection and Engagement (open access)

Blogging and Tweens: Communication Portal to Reading Selection and Engagement

The ethnographic study utilized the research techniques of observations, content analysis, and semi-structured interviews with tween participants (i.e., 9 through 13 year-old youth) during an 8-week literary blog project. Twenty-six participants created individual blog pages within a member-only classroom blog site that allowed for online communication between members. the blog project incorporated social networking applications with which youth frequently engage. the research questions ensured data regarding what facets participants found appealing and motivating during the project was collected. the questions allowed for determining if participants utilized peer blogs for reading material selection or repurposed the blogs to discuss other topics. Components of self-determination theory and engagement theory underlay the project design and aided in identifying motivational aspects of the data. Frequency tables outlined the identified patterns and structures of participants’ online activity. Participants found the ability to change the colors of their blog backgrounds and to design their individual blogs and the giving and receiving of feedback to be the two most appealing features of the project. Participants chose books from peer suggestions in the online world but also selected materials from recommendations they received in face-to-face interactions with their peers, their teacher, and the school librarian. Little evidence of …
Date: May 2012
Creator: Sharber, Shelli K.
System: The UNT Digital Library
The Effects of Textual Fluency on the Rate of Acquisition and Application of Intraverbal Relations (open access)

The Effects of Textual Fluency on the Rate of Acquisition and Application of Intraverbal Relations

Intraverbal behavior governs core elements of academic and intellectual behavior. These intraverbal relations can be explicitly taught when an individual is prompted to provide an appropriate response with pictures, text, or other stimuli following a verbal stimulus. It is possible that a focus on fluency of the target repertoires may lead to more conclusive data. the current study assessed the effects of precision teaching based instruction for component textual repertoires on the acquisition of intraverbal relations. Specifically, this study compared the effectiveness of two textual prompting procedures (with and without fluency-based instruction) on the acquisition and application of intraverbal relations using time-delay and a carefully controlled set of intraverbal stimuli. Results indicate that the use of textual prompts and an errorless time-delay transfer of stimulus control procedure were effective strategies for teaching intraverbal responses regardless of the inclusion of fluency-based instruction.
Date: May 2012
Creator: Shrontz, Rachael E.
System: The UNT Digital Library
Random Iteration of Rational Functions (open access)

Random Iteration of Rational Functions

It is a theorem of Denker and Urbański that if T:ℂ→ℂ is a rational map of degree at least two and if ϕ:ℂ→ℝ is Hölder continuous and satisfies the “thermodynamic expanding” condition P(T,ϕ) > sup(ϕ), then there exists exactly one equilibrium state μ for T and ϕ, and furthermore (ℂ,T,μ) is metrically exact. We extend these results to the case of a holomorphic random dynamical system on ℂ, using the concepts of relative pressure and relative entropy of such a system, and the variational principle of Bogenschütz. Specifically, if (T,Ω,P,θ) is a holomorphic random dynamical system on ℂ and ϕ:Ω→ ℋα(ℂ) is a Hölder continuous random potential function satisfying one of several sets of technical but reasonable hypotheses, then there exists a unique equilibrium state of (X,P,ϕ) over (Ω,Ρ,θ).
Date: May 2012
Creator: Simmons, David
System: The UNT Digital Library
Personalities and Pipelines: Exploring the Role of Personality in Student Self-selection Into Stem Majors (open access)

Personalities and Pipelines: Exploring the Role of Personality in Student Self-selection Into Stem Majors

Despite all the national efforts to increase STEM enrollment in the United States, the gap between the U.S. and other developed countries in terms of STEM graduates has widened over the last 20 years. Researchers have studied factors such as gender, race, high school GPA, and the student’s socioeconomic status for their impact on STEM enrollment. This study offers another possible explanation of why students might choose, or not choose, to enroll in STEM majors by examining the relationship between personality and STEM enrollment. the sample included 2,745 respondents to the 2008 Cooperative Institutional Research Program freshman survey at a large research university in the southwestern United States. Factor analysis was used to create four personality scales, based on John Holland’s theory of personality types, with items selected from the survey. Logistic regression was utilized to answer three research questions: Are students classified as a strong investigative personality type more likely to enroll in STEM majors than students classified as a weak investigative personality type? Are there differences in their likelihood to enroll in STEM majors among students of investigative-social, investigative-artistic, and investigative-enterprising personality types? What effect does personality have on students’ self-selection into a biological versus a physical STEM …
Date: May 2012
Creator: Simpson, Patricia
System: The UNT Digital Library
Studies on Plant-aphid Interactions: a Novel Role for Trehalose Metabolism in Arabidopsis Defense Against Green Peach Aphid (open access)

Studies on Plant-aphid Interactions: a Novel Role for Trehalose Metabolism in Arabidopsis Defense Against Green Peach Aphid

Myzus persicae (Sülzer), commonly known as the green peach aphid (GPA), is a polyphagous insect that can infest over 100 families of economically important plants and is major pest for vegetable crops. This study utilizes the Arabidopsis-GPA model system with the aim to elucidate the role of the plant disaccharide trehalose in providing defense against GPA. This study demonstrates a novel role for TPS11 in providing defense against GPA. TPS11 expression was found to be transiently induced in Arabidopsis plants in response to GPA infestation and the TPS11 gene was required for curtailing GPA infestation. TPS11, which encodes for trehalose phosphate synthase and phosphatase activities, contributes to the transient increase in trehalose in the GPA infested tissues. This work suggests that TPS11-dependent trehalose has a signaling function in plant defense against GPA. in addition, trehalose also has a more direct role in curtailing GPA infestation on Arabidopsis. This work also shows that TPS11 is able to modulate both carbohydrate metabolism and plant defenses in response to GPA infestation. the expression of PAD4, an Arabidopsis gene required for phloem-based defenses against GPA, was found to be delayed in GPA infested tps11 mutant plants along with increased sucrose levels and lower starch …
Date: May 2012
Creator: Singh, Vijay
System: The UNT Digital Library
Exploring the Relationships Between Mindfulness, Self-compassion, and Ethnic Identity Development (open access)

Exploring the Relationships Between Mindfulness, Self-compassion, and Ethnic Identity Development

Ethnic identity development is a process that occurs for all individuals, and weakness in ethnic identity is associated with numerous psychosocial difficulties. Security in ethnic identity can be difficult for those exposed to varying attitudes and behaviors in a multicultural society. As such, the current study examined the influence of mindfulness and self-compassion on ethnic identity development. a sample of 479 undergraduate students completed online self-report questionnaires measuring demographic information, mindfulness, self-compassion, ethnic identity status, and self-esteem. Results suggested that mindfulness and self-compassion are significant negative predictors of ethnic identity, and that self-compassion was a better predictor of ethnic identity status than was mindfulness. Self-compassion did not moderate the relationship between mindfulness and ethnic identity status, as was hypothesized. the sample included primarily Caucasian (n = 278) individuals born in the United States, which likely limited generalizability of findings. Implications of the current findings and suggestions for future research are discussed.
Date: May 2012
Creator: Sinha, Aditi
System: The UNT Digital Library
Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation (open access)

Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade over 10 weeks. Results indicate responses of Fimbristylis vahlii and Ammannia robusta are consistent with tradeoffs. Modification of classical allometric responses to shade by substrate saturation indicates a potential mechanism for the tradeoff in A. robusta. Responses indicating potential for increased susceptibility to physical flooding disturbance are also discussed.
Date: May 2012
Creator: Sloop, Jordan
System: The UNT Digital Library
A Comparison of Mercury Localization, Speciation, and Histology in Multiple Fish Species From Caddo Lake, a Fresh Water Wetland (open access)

A Comparison of Mercury Localization, Speciation, and Histology in Multiple Fish Species From Caddo Lake, a Fresh Water Wetland

This work explores the metabolism of mercury in liver and spleen tissue of fish from a methylmercury contaminated wetland. Wild-caught bass, catfish, bowfin and gar were collected. Macrophage centers, which are both reactive and primary germinal centers in various fish tissues, were hypothesized to be the cause of demethylation of methylmercury in fish tissue. Macrophage centers are differentially expressed in fish tissue based on phylogenetic lineage, and are found primarily in the livers of preteleostean fish and in the spleen of teleostean fish. Histology of liver and spleen was examined in both control and wild-caught fish for pathology, size and number of macrophage centers, and for localization of mercury. Total mercury was estimated in the muscle tissue of all fish by direct mercury analysis. Selenium and mercury concentrations were examined in the livers of wild-caught fish by liquid introduction inductively coupled plasma mass spectrometry (ICP-MS). Total mercury was localized in histologic sections by laser ablation ICP-MS (LA-ICP-MS). Mercury speciation was determined for inorganic and methylmercury in liver and spleen of fish by bas chromatography-cold vapor atomic fluorescence spectroscopy (GC-CVAFS). Macrophage center tissue distribution was found to be consistent with the literature, with a predominance of centers in preteleostean liver and …
Date: May 2012
Creator: Smith, James Durward
System: The UNT Digital Library
Examining the Engagement of Transfer Students in Texas Universities (open access)

Examining the Engagement of Transfer Students in Texas Universities

The success of transfer students plays a critical role in improving the baccalaureate attainment rates of undergraduates attending 4-year higher education institutions in Texas; however, current indicators suggest transfer students have lower persistence and graduation rates relative to students who begin and complete their college education at one university (i.e., non-transfer students). Additionally, the research literature indicates a link between degree completion and engagement; however, transfer students are reported to be less engaged and less likely to persist than their counterparts. This quantitative study compared the engagement experiences of 2-year transfers, 4-year transfers, swirl transfer, and non-transfers by using National Survey of Student Engagement (NSSE) 2008 data to determine if there are any differences among these groups, and if these differences persist after controlling for individual and institutional covariates. the sample consisted of 2,000 seniors attending 4-year higher education institutions in Texas. the engagement scores of each group were compared using a multivariate analysis (MANOVA). This study found non-transfers were more engaged than each type of transfer student on Student-Faculty Interaction and Supportive Campus Environment factors; moreover, these differences generally persisted after controlling for residence, enrollment status, and institutional control (i.e., public vs. private).The data indicated no difference among the …
Date: May 2012
Creator: Fernander, Keith A.
System: The UNT Digital Library
A Multiscalar Analysis of Buruli Ulcer in Ghana: Environmental and Behavioral Factors in Disease Prevalence (open access)

A Multiscalar Analysis of Buruli Ulcer in Ghana: Environmental and Behavioral Factors in Disease Prevalence

Buruli ulcer (BU), an infectious disease caused by Mycobacterium ulcerans, is the third most common mycobacterial disease after leprosy and tuberculosis and a WHO-defined neglected tropical disease. Despite years of research, the mode of transmission of BU remains unknown. This master’s thesis provides an integrated spatial analysis of disease dynamics in Ghana, West Africa, an area of comparatively high BU incidence. Within a case/matched control study design, environmental factors associated with BU infection and spatial behaviors are investigated to uncover possible links between individual daily activity spaces and terrains of risk across disturbed landscapes. This research relies upon archival and field-collected data and analyses conducted with geographical information systems (GIS).
Date: May 2012
Creator: Ferring, David
System: The UNT Digital Library
Continuity of Caste: Free People of Color in the Vieux Carré of New Orleans, 1804-1820 (open access)

Continuity of Caste: Free People of Color in the Vieux Carré of New Orleans, 1804-1820

Because of its trademark racial diversity, historians have often presented New Orleans as a place transformed by incorporation into the American South following 1804. Assertions that a comparatively relaxed, racially ambiguous Spanish slaveholding regime was converted into a two-caste system of dedicated racial segregation by the advent of American assumption have been posited by scholars like Frank Tannenbaum, Gwendolyn Midlo Hall, and a host of others. Citing dependence on patronage, concubinage, and the decline in slave manumissions during the antebellum period, such studies have employed descriptions of the city’s prominent free people of color to suggest that the daily lives of non-whites in New Orleans experienced uniform restriction following 1804, and that the Crescent City’s transformation from Atlantic society with slaves to rigid slave society forced free people of color out of the heart of the city, known as the Vieux Carré, and into “black neighborhoods” on the margins of town. Despite the popularity of such generalized themes in the historiography, however, the extant sources housed in New Orleans’s valuable archival repositories can be used to support a vastly divergent narrative. By focusing on individual free people of color, or libres, rather than the non-white community as a whole, this …
Date: May 2012
Creator: Foreman, Nicholas
System: The UNT Digital Library
The Beauty of Nature As a Foundation for Environmental Ethics: China and the West (open access)

The Beauty of Nature As a Foundation for Environmental Ethics: China and the West

My dissertation aims at constructing an environmental ethics theory based on environmental aesthetics in order to advocate and promote environmentally sustainable practices, policies, and lifestyles. I attempt to construct an integrated environmental aesthetics in order to inspire people’s feelings of love towards nature and motivate them to protect it. In order to achieve this goal, I first examine the philosophical understanding and aesthetic appreciation of nature from philosophical traditions of China, which have an impact on the general public’s attitude towards nature. in chapter one of my dissertation, I point out that nature is viewed as an organic system which is always in a self-generating process of production and reproduction of life. the metaphysical foundation for this perspective of nature is ch’i. Therefore the aesthetic appreciation of nature in China is also the aesthetic appreciation of ch’i. with regard to the concept of ch’i, I focus on the following three questions: (1) what are the objective and aesthetic features of ch’i? (2) How do the Chinese appreciate aesthetic features of ch’i? (3) Why the objective features of ch’i are regarded as the objects of aesthetic appreciation? I argue that the Chinese appreciate the aesthetic features of ch’i by using intellectual …
Date: May 2012
Creator: Gao, Shan
System: The UNT Digital Library
Metamodeling-based Fast Optimization of  Nanoscale Ams-socs (open access)

Metamodeling-based Fast Optimization of Nanoscale Ams-socs

Modern consumer electronic systems are mostly based on analog and digital circuits and are designed as analog/mixed-signal systems on chip (AMS-SoCs). the integration of analog and digital circuits on the same die makes the system cost effective. in AMS-SoCs, analog and mixed-signal portions have not traditionally received much attention due to their complexity. As the fabrication technology advances, the simulation times for AMS-SoC circuits become more complex and take significant amounts of time. the time allocated for the circuit design and optimization creates a need to reduce the simulation time. the time constraints placed on designers are imposed by the ever-shortening time to market and non-recurrent cost of the chip. This dissertation proposes the use of a novel method, called metamodeling, and intelligent optimization algorithms to reduce the design time. Metamodel-based ultra-fast design flows are proposed and investigated. Metamodel creation is a one time process and relies on fast sampling through accurate parasitic-aware simulations. One of the targets of this dissertation is to minimize the sample size while retaining the accuracy of the model. in order to achieve this goal, different statistical sampling techniques are explored and applied to various AMS-SoC circuits. Also, different metamodel functions are explored for their …
Date: May 2012
Creator: Garitselov, Oleg
System: The UNT Digital Library
The Relationship Between Cardiorespiratory Fitness and Bmi, Depressive Symptoms, and School Absences Among a Racial/ethnically Diverse Sample of Early Adolescents (open access)

The Relationship Between Cardiorespiratory Fitness and Bmi, Depressive Symptoms, and School Absences Among a Racial/ethnically Diverse Sample of Early Adolescents

The current study examined the relationship between cardiorespiratory fitness on differences by sex, race/ethnicity, and SES on BMI, depressive symptoms, and school absences among adolescents. a cross-sectional study was conducted in a north Texas school district, which included 609 Caucasian/Whites, 293 Hispanic/Latinos, and 113 African-American/Black adolescents (10-14 years). Main results of the study showed that that cardiorespiratory fitness was the largest predictor of BMI, followed by race/ethnicity, and then sex. Cardiorespiratory fitness among adolescents was inversely associated with BMI. the relationship between cardiorespiratory fitness on BMI appeared to be more salient for non-Hispanic white females and non-Hispanic black females in that the former group had lower BMI scores than the latter group when cardiorespiratory fitness was taken into account; however, results showed that non-Hispanic white females and non-Hispanic black females had similar cardiorespiratory fitness level. Other results showed that SES and sex predicted depressive symptoms in that low SES females endorsed more depressive symptoms relative to high SES males; however, this relationship was non-existent when cardiorespiratory fitness was entered into the model. Additionally, findings indicated that BMI and depressive symptoms equally predicted school absences in that adolescents who had a higher BMI and endorsed more depressive symptoms had more school …
Date: May 2012
Creator: Garza, Mariana
System: The UNT Digital Library