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Effects and Mediation of Child-centered Play Therapy on Young Children Who Are Anxious

Description: Anxiety is one of the most pervasive childhood disorders, with a poor prognosis if left untreated. Traditional methods of treating anxiety have been less effective with young children. Based on theoretical assumptions regarding the potential effectiveness of child-centered play therapy (CCPT) as a treatment approach, I sought to explore the effects and mediating factors of CCPT on young children with symptoms of anxiety. Fifty-three participants between the ages of 6 to 8 years old were recruited from four elementary schools, including 36 males and 17 females. Of participants, 11 were African American, 24 were Caucasian, 10 were Hispanic/Latino, one was Asian, and seven were biracial. Twenty-five participants were randomly assigned to an experimental group receiving a mean of 15 sessions of individual CCPT, and 28 participants were assigned to an 8-session active control group. Five factorial analyses of variance (ANOVA) were conducted applying an alpha level of .05 for interpretation of statistical significance and Cohen’s d to assess practical significance. ANOVA results indicated a statistically significant interaction with a large effect size on Total Anxiety score of the Revised Children’s Manifest Anxiety Scale-2nd edition (p = .013, d = .715). Subscale ANOVA results indicated a statistically significant interaction effect with large effect size on the Worry subscale (p = .006, d = .795), no statistically significant interaction on the Defensiveness subscale (p = .710, d = .110), no statistically significant interaction but moderate effect size on the Physiological subscale (p = .076, d = .506), and no statistically significant interaction but moderate effect size on the Social Anxiety subscale (p = .162, d = .398). Statistically significant differences with large practical effects were found in total anxiety and worry, suggesting that children who received CCPT decreased their overall levels of anxiety and worry whereas children who were in the active ...
Date: May 2014
Creator: Stulmaker, Hayley L.
Partner: UNT Libraries

Racial/ethnic Differences in Hospital Utilization for Cardiovascular-related Events: Evidence of a Survival and Recovery Advantage for Latinos?

Description: Evidence continues to demonstrate that racial/ethnic minority groups experience a disproportionate burden of disease and mortality in cardiovascular-related diseases (CVDs). However, emerging evidence suggests a health advantage for Latinos despite a high risk profile. The current study explored the hospital utilization trends of Latino and non-Latino patients and examined the possibility of an advantage for Latinos within the context of CVD-related events with retrospective data collected over a 12-month period from a local safety-net hospital. Contrary to my hypotheses, there was no advantage for in-hospital mortality, length of stay or re-admission in Latinos compared to non-Latinos; rather, Latinos hospitalized for a CVD-related event had a significantly longer length of stay and had greater odds for re-admission when compared to non-Latinos. Despite data suggesting a general health advantage, Latinos may experience a relative disparity within the context of hospital utilization for CVD-related events. Findings have implications for understanding the hospital utilization trends of Latinos following a CVD-related event and suggest a call for action to advance understanding of Latino cardiovascular health.
Date: May 2014
Creator: García, James J.
Partner: UNT Libraries

Engaging Lives: a Nomadic Inquiry Into the Spatial Assemblages and Ethico-aesthetic Practices of Three Makers

Description: This research is a nomadic inquiry into the ethics and aesthetics of three makers’ social and material practices. Deleuze’s concept of the nomad operated in multiple ways throughout the process, which was embedded in performative engagements that produced narratives of becoming. Over four months, I built relationships with three people as I learned about the ethico-aesthetic significance of their daily practices. The process started by interviewing participants in their homes and expanded over time to formal and informal engagements in school, community, and agricultural settings. I used Guattari’s ecosophical approach to consider how subjectivity was produced through spatial assemblages by spending time with participants, discussing material structures and objects, listening to personal histories, and collaboratively developing ideas. Participants included a builder who repurposed a missile base into a private residence and community gathering space, an elementary art teacher who practiced urban homesteading, and a young artist who developed an educational farm. The research considers the affective force of normalized social values, the production of desire by designer capitalism, and the mutation of life from neoliberal policies. Our experiences illuminate the community-building potential of direct encounters and direct exchanges. The project generates ideas for becoming an inquirer in the everyday and reveals possibilities for producing pedagogical experiences through collective and dissensual action. Ultimately, the project produces hope for performative and anti-disciplinary approaches to education, rupturing false divisions that fragment the force of thought, to produce, instead, aesthetic experiences that privilege processes and are based in direct and collective engagements with life.
Date: May 2014
Creator: Coats, Cala R.
Partner: UNT Libraries

Development of High Gain Ultraviolet Photo Detectors Based on Zinc Oxide Nanowires

Description: Semiconductor nanowires acts as an emerging class of materials with great potential for applications in future electronic devices. Small size, large surface to volume ratio and high carrier mobility of nanowires make them potentially useful for electronic applications with high integration density. In this thesis, the focus was on the growth of high quality ZnO nanowires, fabrication of field effect transistors and UV- photodetectros based on them. Intrinsic nanowire parameters such as carrier concentration, field effect mobility and resistivity were measured by configuring nanowires as field effect transistors. The main contribution of this thesis is the development of a high gain UV photodetector. A single ZnO nanowire functioning as a UV photodetector showed promising results with an extremely high spectral responsivity of 120 kA/W at wavelength of 370 nm. This corresponds to high photoconductive gain of 2150. To the best of our knowledge, this is the highest responsivity and gain reported so far, the previous values being responsivity=40 kA/W and gain=450. The enhanced photoconductive behavior is attributed to the presence of surface states that acts as hole traps which increase the life time of photogenerated electrons raising the photocurrent. This work provides the evidence of such solid states and preliminary results to modify the surface of ZnO nanowire is also produced.
Date: May 2014
Creator: Mallampati, Bhargav
Partner: UNT Libraries

Thermally Stimulated Depolarization Current Evaluation of Molding Compounds

Description: TSDC (thermally stimulated depolarization current) is one of the most important and popular technique for investigating electret materials. TSDC technique can indicate the magnitude of polarization and depolarization, relaxation time, charge-storage, glass transition, and activation energy. To fully investigate polarization and relaxation for pure epoxy and filled epoxy materials, a TSDC system was built and verified by the research. The article describes the building processes and verification of the TSDC system. TSDC, TSPC, and TWC tests data for epoxy and filled epoxy samples are presented in the article. To compare TSDC technique with other related techniques, DEA (dielectric analysis), DMA (dynamic mechanical analysis), and DSC (differential scanning calorimetry) tests are introduced.
Date: May 2014
Creator: Zhao, Shunli
Partner: UNT Libraries

Exploratory Analysis of Social E-health Behavior

Description: Extant literature has documented well that people seek health information via the internet as patients and consumers. Much less, however, is known about interaction and creation behaviors in the development of new online health information and knowledge. More specifically, generalizable sociodemographic data on who engages in this online health behavior via social media is lacking in the sociological literature. The term “social e-health” is introduced to emphasize the difference between seeking behaviors and interaction and creation behaviors. A 2010 dataset of a large nationally representative and randomly sampled telephone survey made freely available from the Pew Research Center is used to examine social e-health behavior according to respondents’ sociodemographics. The dependent variable of social e-health behavior is measured by 13 survey questions from the survey. Gender, race, ethnicity, age, education, and income are used as independent variables. Logistic regression analysis was used to determine the odds of engagement in social e-health behavior based on the sociodemographic predictors. The social determinants of health and digital divide frameworks are used to help explain why socioeconomic variances exist in social e-health behavior. The findings of the current study suggest that predictable sociodemographic patterns along the dimensions of gender, race, age, education, and income exist for those who report engaging in social e-health behavior. This study is important because it underscores the fact that engagement in social e-health behavior is differentially distributed in the general U.S. population according to patterned sociodemographics.
Date: May 2014
Creator: Acadia, Spencer
Partner: UNT Libraries

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.
Partner: UNT Libraries

Thermoplastic and Thermoset Natural Fiber Composite and Sandwich Performance

Description: The objective of this thesis is to investigate the effects of adding natural fiber (kenaf fiber, retted kenaf fiber, and sugarcane fiber) into polymer materials. The effects are obtained by considering three main parts. 1. Performance in thermoplastic composites. The effect of fiber retting on polymer composite crystallization and mechanical performance was investigated. PHBV/PBAT in 80/20 blend ratio was modified using 5% by weight kenaf fiber. Dynamic mechanical analysis of the composites was done to investigate the glass transition and the modulus at sub-ambient and ambient temperatures. ESEM was conducted to analyze fiber topography which revealed smoother surfaces on the pectinase retted fibers. 2. Performance in thermoset composites. The effect of the incorporation of natural fibers of kenaf and of sugarcane combined with the polyester resin matrix is investigated. A comparison of mechanical properties of kenaf polyester composite, sugarcane polyester composite and pure polyester in tensile, bending, dynamic mechanical thermal analysis (DMA) and moisture test on performance is measured.. 3. Performance in sandwich composites. The comparison of the performance characteristics and mechanical properties of natural fiber composites panels with soft and rigid foam cores are evaluated. A thorough test of the mechanical behavior of composites sandwich materials in tensile, bending and DCB is presented here.
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Date: May 2014
Creator: Yang, Bing
Partner: UNT Libraries

Geek As a Constructed Identity and a Crucial Component of Stem Persistence

Description: The fields of science, technology, engineering and mathematics (STEM) have long been the bastions of the white male elite. Recently, academia has begun to recognize gender and ethnic disparities. In an effort to expand the recruitment pool for these STEM fields in college, various efforts have been employed nationally at the secondary level. In California, the latest of these efforts is referred to as Linked Learning, a pedagogy that combines college preparation with career preparation. The current study is investigating the connection between what has been referred to in current scholarship as "Geeking Out" with higher academic performance. The phenomenon of “Geeking Out” includes a variety of non-school related activities that range from participating in robotics competitions to a simple game of Dungeons & Dragons. The current project investigates the relationship between long term success in STEM fields and current informal behaviors of secondary students. This particular circumstance where Linked Learning happens to combine with "Geeking Out" is successful due to the associated inclusionary environment. Methods included a yearlong ethnographic study of the Center for Advanced Research and Technology, a Central Valley school with a diverse student body. Through participant observation and interviews, the main goal of this research is to examine the circumstances that influence the effectiveness found in the environment of the Center for Advanced Research and Technology.
Date: May 2014
Creator: Liggett, Joshua B.
Partner: UNT Libraries

A Philosophy and an Approach to Teaching Non-professional-track Violin Students

Description: The aim of this dissertation is to lay the groundwork for an integrated approach to violin instruction for children who are not being groomed explicitly for professional careers as instrumentalists. The study presents a particular focus on the age of middle school children, in order to showcase a more specialized and definitive result of research without, however, distinguishing between advantages and limitations of different age groups of children who study music and learn to play the violin. My first goal is to craft a sample method of teaching with a premise that not all students studying music must or need to become professional musicians in their future. I promote an approach based on the premise that music has universal value available to all and that any kind of music education encourages the growth, personality development, and imagination of children. My second goal is to explore how music education functions in 21st century western culture. Research is based on teachings and methods established by Suzuki, Kodaly, Jaques-Dalcroze, and Orff, among others.
Date: May 2014
Creator: Bard-Schwarz, Anna Ewa
Partner: UNT Libraries

Douglas Campbell: American Horn Pedagogue and Performer

Description: While the word “pedagogue” may evoke a vision of an instructor who is dogmatic and set in his own ways, the word descends from Greek origins: ped “child” + agogos “leader.” A pedagogue is, by definition, literally the servant who escorts the child to and from school – the “pedagogue” accompanies the student on the journey for knowledge. True to this definition, Douglas Campbell is model pedagogue – one who gently guided his countless students throughout their musical journeys. As Professor of Music (Horn) at Michigan State University for 45 years, and Horn Instructor at Interlochen Arts Camp for 25 years, Campbell was a significant influence on many developing hornists. Following their study with him, Campbell's students eventually won orchestral and college teaching positions across the United States and throughout the world. Having influenced an extraordinary number of horn students during his tenures at Michigan State University and Interlochen Arts Camp, Douglas Campbell's life and career serve as an excellent example of contemporary horn pedagogy in the United States. This dissertation provides a detailed biography of Douglas Campbell and provides evidence of his contributions to American horn pedagogy, while documenting Campbell’s performing career with the Richards Quintet, which toured the United States, Canada, and China. Additionally, compositions written for or commissioned by Campbell (Harmonielehre: Variations for Solo Horn [1996] and Epitaph [2012]) are discussed, to illustrate Campbell's influence on solo literature for the horn.
Date: May 2014
Creator: Suchodolski, Heather Blase
Partner: UNT Libraries

A Vygotskian Analysis of Preservice Teachers’ Conceptions of Dissolving and Density

Description: The purpose of this study was to examine the content knowledge of 64 elementary preservice teachers for the concepts of dissolving and density. Vygotsky’s (1987) theory of concept development was used as a framework to categorize concepts and misconceptions resulting from evidences of preservice teacher knowledge including pre/post concept maps, writing artifacts, pre/post face-to-face interviews, examination results, and drawings. Statistical significances were found for pre- and post-concept map scores for dissolving (t = -5.773, p < 0.001) and density (t = -2.948, p = 0.005). As measured using Cohen’s d values, increases in mean scores showed a medium-large effect size for (dissolving) and a small effect size for density. The triangulated results using all data types revealed that preservice teachers held several robust misconceptions about dissolving including the explanation that dissolving is a breakdown of substances, a formation of mixtures, and/or involves chemical change. Most preservice teachers relied on concrete concepts (such as rate or solubility) to explain dissolving. With regard to density, preservice teachers held two robust misconceptions including confusing density with buoyancy to explain the phenomena of floating and sinking, and confusing density with heaviness, mass, and weight. Most preservice teachers gained one concept for density, the density algorithm. Most preservice teachers who participated in this study demonstrated Vygotsky’s notion of complex thinking and were unable to transform their thinking to the scientific conceptual level. That is, they were unable to articulate an understanding of either the process of dissolving or density that included a unified system of knowledge characterized as abstract, generalizable, and hierarchical. Results suggest the need to instruct preservice elementary science teachers about the particulate nature of matter, intermolecular forces, and the Archimedes' principle.
Date: May 2014
Creator: Shaker elJishi, Ziad
Partner: UNT Libraries

Energy Paths and Political Commitments: Their Roles in Environmental Inequality

Description: Decentralized renewable energy procurement has gained traction in recent years for its potential to alleviate rural energy poverty and environmental degradation in developing countries. Hence, this study investigates if deploying renewable energy can mitigate rural energy poverty in developing countries as often claimed. Because any energy regime cannot be initiated or sustained without the conviction of local political leaders, the study also evaluates the extent to which government investments in the development of renewable energy technologies and the energy sector, affect the environmental quality (i.e. greenhouse gas emissions) of developing countries. Energetic theory and environmental inequality constitute the key conceptual premises guiding this study. Ordinary least squares regression is utilized to analyze the relationship between key variables. The results reveal that as of 2010, use of renewable energy can indeed support rural electrification. Higher GNI per capita and use of conventional fuels are also positively related to rural electrification, all else equal. As for environmental degradation in 2005 and 2008, R&D investments actually tend to increase GHG emissions; procuring energy from either renewable or non-renewable sources is however, found to be environmentally detrimental, net of all other variables. Finally, some evidence is found for the role of aid funds and multilateral debt in abating GHG emissions.
Date: May 2014
Creator: Ong, Corinne
Partner: UNT Libraries

An Implementation of Consensus Through Bluetooth Communication

Description: This thesis provides an implementation of consensus of multi-agent networked systems. Consensus problem is an important issue of distributed computing and has various algorithms and applications in the field of electronical and computer science. The consensus requests all nodes of a network reach an agreement over a certain measurement. An algorithm of convergent consensus problem is implemented through a small network of Bluetooth communication in the thesis. The connections of the Bluetooth devices are wireless, and the device nodes of the network are driven by C++ software and Winsock API. The simulation results show that the implementation completes all the requirements of the distributed consensus algorithm.
Date: May 2014
Creator: Wang, Yinan
Partner: UNT Libraries

Experiences and Perceptions of Students in Music and Mathematics

Description: Since the time of Pythagoras, philosophers, educators, and researchers have theorized that connections exist between music and mathematics. While there is little doubt that engaging in musical or mathematical activities stimulates brain activity at high levels and that increased student involvement fosters a greater learning environment, several questions remain to determine if musical stimulation actually improves mathematic performance. This study took a qualitative approach that allowed 24 high school students to express their direct experiences with music and mathematics, as well as their perceptions of how the two fields are related. Participants were divided into four equal groups based on school music participation and level of mathematic achievement, as determined by their performance on the Texas Assessment of Knowledge and Skills (TAKS). Students participated in a series of three interviews addressing their experiences in both music and mathematics, and took the Multiple Intelligences Developmental Assessment Scales (MIDAS). TAKS data and MIDAS information were triangulated with interview findings. Using a multiple intelligence lens, this study addressed the following questions: (a) How do students perceive themselves as musicians and mathematicians? (b) What experiences do students have in the fields of music and mathematics? (c) Where do students perceive themselves continuing in the fields of music and mathematics? and (d) How do students perceive the fields of music and mathematics relating to each other? Contrary to most existing literature, the students who perceived a connection between the two fields saw mathematics driving a deeper understanding of the musical element of rhythm. Not surprisingly, students with rich backgrounds in music and mathematics had a higher perception of the importance of those fields. Further, it became readily apparent that test data often played a minimal role in shaping student perceptions of themselves in the field of mathematics. Finally, it became apparent from listening to the ...
Date: May 2014
Creator: Cranmore, Jeff L.
Partner: UNT Libraries

The Mechanisms of Methane C–H Activation and Oxy-insertion Via Small Transition Metal Complexes: a DFT Computational Investigation

Description: Our country continues to demand clean renewable energy to meet the growing energy needs of our time. Thus, natural gas, which is 87% by volume of methane, has become a hot topic of discussion because it is a clean burning fuel. However, the transportation of methane is not easy because it is a gas at standard temperature and pressure. The usage of transition metals for the conversion of small organic species like methane into a liquid has been a longstanding practice in stoichiometric chemistry. Nonetheless, the current two-step process takes place at a high temperature and pressure for the conversion of methane and steam to methanol via CO + H2 (syngas). The direct oxidation of methane (CH4) into methanol (CH3OH) via homogeneous catalysis is of interest if the system can operate at standard pressure and a temperature less than 250 C. Methane is an inert gas due to the high C-H bond dissociation energy (BDE) of 105 kcal/mol. This dissertation discusses a series of computational investigations of oxy-insertion pathways to understand the essential chemistry behind the functionalization of methane via the use of homogeneous transition metal catalysis. The methane to methanol (MTM) catalytic cycle is made up of two key steps: (1) C-H activation by a metal-methoxy complex, (2) the insertion of oxygen into the metal−methyl bond (oxy-insertion). While, the first step (C-H activation) has been well studied, the second step has been less studied. Thus, this dissertation focuses on oxy-insertion via a two-step mechanism, oxygen-atom transfer (OAT) and methyl migration, utilizing transition metal complexes known to activate small organic species (e.g., PtII and PdII complexes). This research seeks to guide experimental investigations, and probe the role that metal charge and coordination number play.
Date: May 2014
Creator: Prince, Bruce M.
Partner: UNT Libraries

Daily-collected Sleep Diaries Compared to Weekly-collected Sleep Diaries Via Actigraph Concordance

Description: Both sleep diaries and actigraphy have been recommended to assess sleep in research and clinical settings. Investigators have traditionally used sleep diaries that were completed daily by participants and collected weekly but have recently begun using sleep diaries that are both completed and collected daily. No research had previously assessed the agreement between daily-collected sleep diaries and actigraph data over one week. Undergraduate students were randomly assigned to use daily- or weekly-collected sleep diaries. Sleep parameters obtained from these measures were compared to each other via concordance with concurrent actigraph data. It was hypothesized that daily-collected sleep diaries would have greater concordance with actigraphy than weekly-collected sleep diaries. Results indicated that daily-collected sleep diaries provided more reliable data than weekly-collected sleep diaries, but the differences were not statistically significant. Additional aims examined self-reported sleep diary adherence, the participation day number, and day of the week. There were trends for the Daily group to have better adherence. Overall concordance did not change based on the day number or day of the week. Both sleep diaries yield comparable sleep parameter data, suggesting that clinicians and researchers can use either method to estimate sleep parameters.
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Date: May 2014
Creator: Francetich, Jade M.
Partner: UNT Libraries

A Study of Novice Special Education Teachers’ Preparation to Teach Students with Autism Spectrum Disorders

Description: The purpose of this study is to identify novice teachers’ perception of their preparedness to teach a class designed for students with autism spectrum disorder (ASD) after graduation from a traditional university-based special education program or from a special education alternative certification program. Teacher preparedness and the need for highly qualified teachers of students with ASD are relevant topics, as the prevalence rate of ASD continues to increase. This phenomenological qualitative study explores novice teachers’ perceptions of preparedness to teach students with ASD and their knowledge about teaching students with ASD. Semi-structured, in-depth interviews were conducted with six novice special education teachers of students with ASD. Results indicated that novice teachers of students with ASD have knowledge of autism and evidence-based practices (EBP), which they ascertained primarily through experiences such as; working directly with students with ASD, however, preservice education programs provided the participants with cursory information related to knowledge of ASD and EBP.
Date: May 2014
Creator: Callaway, Stacey E.
Partner: UNT Libraries

Underground Men: Alternative Masculinities and the Politics of Performance in African American Literature and Culture

Description: This study explores intersections between performance, race and masculinity within a variety of expressive cultural contexts during and after the African American Civil Rights Movement. I maintain that the work of James Baldwin is best situated to help us navigate this cross section, as his fiction and cultural criticism focus heavily on the stage in all its incarnations as a space for negotiating the possibilities and limits of expressive culture in combating harmful racial narratives imposed upon black men in America. My thesis begins with a close reading of the performers populating his story collection Going to Meet the Man (1965) before broadening my scope in the following chapters to include analyses of the diametric masculinities in the world of professional boxing and the black roots of the American punk movement. Engaging with theorists like Judith Butler, bell hooks and Paul Gilroy, Underground Men attempts to put these seemingly disparate corners of American life into a dynamic conversation that broadens our understanding through a novel application of critical race, gender and performance theories. Baldwin and his orbiting criticism remain the hub of my investigation throughout, and I use his template of black genius performance outlined in works like Tell Me How Long the Train’s Been Gone (1967) and Just Above My Head (1977) to aid our understanding of how performance prescribes and scrambles dominant narratives about black men after the sexual revolution.
Date: May 2014
Creator: Gray, Jezy J.
Partner: UNT Libraries

Low Leakage Asymmetric Stacked Sram Cell

Description: Memory is an important part of any digital processing system. On-chip SRAM can be found in various levels of the memory hierarchy in a processor and occupies a considerable area of the chip. Leakage is one of the challenges which shrinking of technology has introduced and the leakage of SRAM constitutes a substantial part of the total leakage power of the chip due to its large area and the fact that many of the cells are idle without any access. In this thesis, we introduce asymmetric SRAM cells using stacked transistors which reduce the leakage up to 26% while increasing the delay of the cell by only 1.2% while reducing the read noise margin of the cell by only 15.7%. We also investigate an asymmetric cell configuration in which increases the delay by 33% while reduces the leakage up to 30% and reducing the read noise margin by only 1.2% compared to a regular SRAM cell.
Date: May 2014
Creator: Ahrabi, Nina
Partner: UNT Libraries

Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?

Description: There were two main purposes of this quantitative study. The first purpose was to identify characteristics associated with the selected sample of academic advisors that comprise study. Secondly, the study sought to determine how well work related activities of a selected population of academic advisors correlate with professional characteristics constructs and professional standards constructs of academic advising as a profession. The study used Habley’s (1986) characteristics of a profession to derive the studies professional characteristic construct, education activities, research activities, and professional development activities as it relates to a selected group of academic advisors work related activities. The studies professional standards construct was derived from five Council for the Advancement of Standards (CAS) professional standards for academic as it relates to a selected group of academic advisors work related activities. The study of 78 out of 210 identified full-time academic advisors at two-and four-year public colleges and universities in the North Texas Region utilized a multidimensional researcher-developed Web survey instrument designed to measure professional standards and characteristic within the field of academic advising. Study results reinforced current criticism of research and education activities within the field of academic advising showing that the lack of scholarly research and education activities among academic advisors decreases significantly their efforts towards professionalization. Also, professional standards construct results suggest that the utilization of CAS standards for academic advising as an evaluation tool may enhance an academic advisor’s knowledge of professional standards within the field.
Date: May 2014
Creator: Shelton, Kiesha R.
Partner: UNT Libraries

Targeted and Metal-loaded Polymeric Nanoparticles As Potential Cancer Therapeutics

Description: Polymeric nanoparticles were designed, synthesized, and loaded with metal ions to explore the therapeutic potential for transition metals other than platinum found in cisplatin. Nanoparticles were synthesized to show the potential for polymer based vectors. Metal loading and release were characterized via Inductively Coupled Plasma Mass Spectrometry (ICP MS), Energy Dispersive X-Ray Spectroscopy (EDX), X-Ray Photoelectron Spectroscopy (XPS), and Elemental Analysis. Targeting was attempted with the expectation of observed increased particle uptake by cancer cells with flow cytometry and fluorescence microscopy. Results demonstrated that a variety of metals could be loaded to the nano-sized carriers in an aqueous environment, and that the release was pH-dependent. Expected increased targeting was inconsistent. The toxicity of these particles was measured in cancer cells where significant toxicity was observed in vitro via dosing of high copper-loaded nanoparticles and slight toxicity was observed in ruthenium-loaded nanoparticles. No significant toxicity was observed in cells dosed with metal-free nanoparticles. Future research will focus on ruthenium loaded polymeric nanoparticles with different targeting ligands dosed to different cell lines for the aim of increased uptake and decreased cancer cell viability.
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Date: May 2014
Creator: Harris, Alesha N.
Partner: UNT Libraries

Processing and Characterization of Nickel-Carbon Base Metal Matrix Composites

Description: Carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) are attractive reinforcements for lightweight and high strength metal matrix composites due to their excellent mechanical and physical properties. The present work is an attempt towards investigating the effect of CNT and GNP reinforcements on the mechanical properties of nickel matrix composites. The CNT/Ni (dry milled) nanocomposites exhibiting a tensile yield strength of 350 MPa (about two times that of SPS processed monolithic nickel ~ 160 MPa) and an elongation to failure ~ 30%. In contrast, CNT/Ni (molecular level mixed) exhibited substantially higher tensile yield strength (~ 690 MPa) but limited ductility with an elongation to failure ~ 8%. The Ni-1vol%GNP (dry milled) nanocomposite exhibited the best balance of properties in terms of strength and ductility. The enhancement in the tensile strength (i.e. 370 MPa) and substantial ductility (~40%) of Ni-1vol%GNP nanocomposites was achieved due to the combined effects of grain refinement, homogeneous dispersion of GNPs in the nickel matrix, and well-bonded Ni-GNP interface, which effectively transfers stress across metal-GNP interface during tensile deformation. A second emphasis of this work was on the detailed 3D microstructural characterization of a new class of Ni-Ti-C based metal matrix composites, developed using the laser engineered net shaping (LENSTM) process. These composites consist of an in situ formed and homogeneously distributed titanium carbide (TiC) as well as graphite phase reinforcing the nickel matrix. 3D microstructure helps in determining true morphology and spatial distribution of TiC and graphite phase as well as the phase evolution sequence. These Ni-TiC-C composites exhibit excellent tribological properties (low COF), while maintaining a relatively high hardness.
Date: May 2014
Creator: Borkar, Tushar Murlidhar
Partner: UNT Libraries

Ddos Defense Against Botnets in the Mobile Cloud

Description: Mobile phone advancements and ubiquitous internet connectivity are resulting in ever expanding possibilities in the application of smart phones. Users of mobile phones are now capable of hosting server applications from their personal devices. Whether providing services individually or in an ad hoc network setting the devices are currently not configured for defending against distributed denial of service (DDoS) attacks. These attacks, often launched from a botnet, have existed in the space of personal computing for decades but recently have begun showing up on mobile devices. Research is done first into the required steps to develop a potential botnet on the Android platform. This includes testing for the amount of malicious traffic an Android phone would be capable of generating for a DDoS attack. On the other end of the spectrum is the need of mobile devices running networked applications to develop security against DDoS attacks. For this mobile, phones are setup, with web servers running Apache to simulate users running internet connected applications for either local ad hoc networks or serving to the internet. Testing is done for the viability of using commonly available modules developed for Apache and intended for servers as well as finding baseline capabilities of mobiles to handle higher traffic volumes. Given the unique challenge of the limited resources a mobile phone can dedicate to Apache when compared to a dedicated hosting server a new method was needed. A proposed defense algorithm is developed for mitigating DDoS attacks against the mobile server that takes into account the limited resources available on the mobile device. The algorithm is tested against TCP socket flooding for effectiveness and shown to perform better than the common Apache module installations on a mobile device.
Date: May 2014
Creator: Jensen, David
Partner: UNT Libraries