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Studies of the structure and function of Mms6, a bacterial protein that promotes the formation of magnetic nanoparticles

Description: Here we report structural and functional studies of Mms6, a biomineralization protein that can promote the formation in vitro of magnetic nanoparticles with sizes and morphologies similar to the magnetites synthesized by magnetotactic bacteria. We found the binding pattern of Mms6 to ferric ion to be two-phase and multivalent. We quantatively determined that Mms6 binds one Fe{sup 3+} with a very high affinity (K{sub d} = 10{sup -16} M). The second phase of iron binding is multivalent and cooper… more
Date: May 15, 2011
Creator: Wang, Lijun
Partner: UNT Libraries Government Documents Department
open access

Mesoporous silica nanoparticles as smart and safe devices for regulating blood biomolecule levels

Description: Stimuli-responsive end-capped MSN materials are promising drug carriers that securely deliver a large payload of drug molecules without degradation or premature release. A general review of the recent progress in this field is presented, including a summary of a series of hard and soft caps for drug encapsulation and a variety of internal and external stimuli for controlled release of different therapeutics, a discussion of the biocompatibility of MSN both in vitro and in vivo, and a descriptio… more
Date: May 15, 2011
Creator: Zhao, Yan
Partner: UNT Libraries Government Documents Department
open access

Antineutrino Oscillations in the Atmospheric Sector

Description: This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for {nu}{sub {mu}} {yields} {bar {nu}}{sub {mu}} transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage … more
Date: May 1, 2011
Creator: Himmel, Alexander I. & /Caltech
Partner: UNT Libraries Government Documents Department
open access

Measurement of low $p_{T}$ $D^{0}$ meson production cross section at CDF II.

Description: In this thesis we present a study of the production of D{sup 0} meson in the low transverse momentum region. In particular the inclusive differential production cross section of the D{sup 0} meson (in the two-body decay channel D{sup 0} {yields} K{sup -}{pi}{sup +}) is obtained extending the published CDF II measurement to p{sub T} as low as 1.5 GeV/c. This study is performed at the Tevatron Collider at Fermilab with the CDF II detector.
Date: May 1, 2011
Creator: Mussini, Manuel & U., /Bologna
Partner: UNT Libraries Government Documents Department
open access

Optimization of Operating Parameters for Minimum Mechanical Specific Energy in Drilling

Description: Efficiency in drilling is measured by Mechanical Specific Energy (MSE). MSE is the measure of the amount of energy input required to remove a unit volume of rock, expressed in units of energy input divided by volume removed. It can be expressed mathematically in terms of controllable parameters; Weight on Bit, Torque, Rate of Penetration, and RPM. It is well documented that minimizing MSE by optimizing controllable factors results in maximum Rate of Penetration. Current methods for computing MS… more
Date: May 25, 2011
Creator: Hamrick, Todd
Partner: UNT Libraries Government Documents Department
open access

Compensation Techniques in Accelerator Physics

Description: Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along w… more
Date: May 31, 2011
Creator: Sayed, Hisham Kamal
Partner: UNT Libraries Government Documents Department
open access

Self-assembled pentablock copolymers for selective and sustained gene delivery

Description: The poly(diethylaminoethyl methacrylate) (PDEAEM) - Pluronic F127 - PDEAEM pentablock copolymer (PB) gene delivery vector system has been found to possess an inherent selectivity in transfecting cancer cells over non-cancer cells in vitro, without attaching any targeting ligands. In order to understand the mechanism of this selective transfection, three possible intracellular barriers to transfection were investigated in both cancer and non-cancer cells. We concluded that escape from the endocy… more
Date: May 15, 2011
Creator: Zhang, Bingqi
Partner: UNT Libraries Government Documents Department
open access

Mesoporous silica nanoparticles for biomedical and catalytical applications

Description: Mesoporous silica materials, discovered in 1992 by the Mobile Oil Corporation, have received considerable attention in the chemical industry due to their superior textual properties such as high surface area, large pore volume, tunable pore diameter, and narrow pore size distribution. Among those materials, MCM-41, referred to Mobile Composition of Matter NO. 41, contains honeycomb liked porous structure that is the most common mesoporous molecular sieve studied. Applications of MCM-41 type mes… more
Date: May 15, 2011
Creator: Sun, Xiaoxing
Partner: UNT Libraries Government Documents Department
open access

The theoretical study of passive and active optical devices via planewave based transfer (scattering) matrix method and other approaches

Description: In this thesis, we theoretically study the electromagnetic wave propagation in several passive and active optical components and devices including 2-D photonic crystals, straight and curved waveguides, organic light emitting diodes (OLEDs), and etc. Several optical designs are also presented like organic photovoltaic (OPV) cells and solar concentrators. The first part of the thesis focuses on theoretical investigation. First, the plane-wave-based transfer (scattering) matrix method (TMM) is bri… more
Date: May 15, 2011
Creator: Zhuo, Ye
Partner: UNT Libraries Government Documents Department
open access

A Search for the Standard Model Higgs Boson Produced in Association with a $W$ Boson

Description: We present a search for a standard model Higgs boson produced in association with a W boson using data collected with the CDF II detector from p{bar p} collisions at {radical}s = 1.96 TeV. The search is performed in the WH {yields} {ell}{nu}b{bar b} channel. The two quarks usually fragment into two jets, but sometimes a third jet can be produced via gluon radiation, so we have increased the standard two-jet sample by including events that contain three jets. We reconstruct the Higgs boson using… more
Date: May 1, 2011
Creator: Frank, Martin Johannes & U., /Baylor
Partner: UNT Libraries Government Documents Department
open access

MicroCantilever (MC) based nanomechanical sensor for detection of molecular interactions

Description: Specific aims of this study are to investigate the mechanism governing surface stress generation associated with chemical or molecular binding on functionalized microcantilevers. Formation of affinity complexes on cantilever surfaces leads to charge redistribution, configurational change and steric hindrance between neighboring molecules resulting in surface stress change and measureable cantilever deformation. A novel interferometry technique employing two adjacent micromachined cantilevers (a… more
Date: May 11, 2011
Creator: Kang, Kyung
Partner: UNT Libraries Government Documents Department
open access

Experimental Study on Fluidization of Biomass, Inert Particles, and Biomass/Sand Mixtures

Description: Fluidization of biomass particles is an important process in the gasification, pyrolysis and combustion in order to extract energy from biomass. Studies on the fluidization of biomass particles (corn cob and walnut shell), inert particles (sand, glass bead, and alumina), which are added to facilitate fluidization of biomass, and biomass/sand mixture were performed. Experiments were carried out in a 14.5 cm internal diameter cold flow fluidization bed to determine minimum fluidization velocities… more
Date: May 2011
Creator: Paudel, Basu
Partner: UNT Libraries
open access

Application of FTIR for Quantification of Alkali in Cement

Description: Alkali-silica reaction (ASR) in cement is a major contributor to failure of cement structures around the world, causing increased repair costs and possible rebuild expenses. Alkali levels are indicative of the potential for ASR and are therefore measured and quantified. A linear correlation relating cement alkali concentration measured by X-ray fluorescence spectroscopy (XRF) and peak ratio measured by Fourier transform infrared spectroscopy (FTIR) is developed. Regression analysis of plots cor… more
Date: May 2011
Creator: Springfield, Tyler
Partner: UNT Libraries
open access

A Pedagogical and Analytical Study of Dušan Bogdanović’s Polyrhythmic and Polymetric Studies for Guitar

Description: Polymeter has been a relatively unexplored compositional technique of music of the Common Practice Period. Dušan Bogdanović’s Polyrhythmic and Polymetric Studies for Guitar is recognized in the guitar world as not only an important theoretical treatise, but also a benchmark for more advanced levels of improvisation. Currently, his treatise remains the best source for learning polymetric improvisation on the guitar. My personal contribution stems from the idea that multiple interpretations of th… more
Date: May 2011
Creator: Morey, Michael J.
Partner: UNT Libraries
open access

Matlab Implementation of a Tornado Forward Error Correction Code

Description: This research discusses how the design of a tornado forward error correcting channel code (FEC) sends digital data stream profiles to the receiver. The complete design was based on the Tornado channel code, binary phase shift keying (BPSK) modulation on a Gaussian channel (AWGN). The communication link was simulated by using Matlab, which shows the theoretical systems efficiency. Then the data stream was input as data to be simulated communication systems using Matlab. The purpose of this paper… more
Date: May 2011
Creator: Noriega, Alexandra
Partner: UNT Libraries
open access

The Effect of Relationship Quality on Mental Representations of Social Support and Cardiovascular Reactivity

Description: The aim of the current study was to examine how thinking about qualitatively different social network members may differentially affect cardiovascular reactivity to a subsequent stressor. Eighty-two undergraduates were asked to think and write about different types of relationships preceding a social stressor. No differences between conditions in CVR were found during social support induction phase or the stressor task. Women in the supportive condition were found to have slower SV recovery th… more
Date: May 2011
Creator: Prather, Courtney C.
Partner: UNT Libraries
open access

Automatic Extraction of Highlights from a Baseball Video Using HMM and MPEG-7 Descriptors

Description: In today’s fast paced world, as the number of stations of television programming offered is increasing rapidly, time accessible to watch them remains same or decreasing. Sports videos are typically lengthy and they appeal to a massive crowd. Though sports video is lengthy, most of the viewer’s desire to watch specific segments of the video which are fascinating, like a home-run in a baseball or goal in soccer i.e., users prefer to watch highlights to save time. When associated to the entire spa… more
Date: May 2011
Creator: Saudagar, Abdullah Naseer Ahmed
Partner: UNT Libraries
open access

Backflow: A Collection

Description: This collection consists of a critical preface and nine essays. The preface analyzes, first, how the imagination influences the personal journey of a writer, and second, the techniques authors use, mainly form, time, and space, to enact the imagination and propel the reader into an imagined narrative. The essays explore themes of loss, mental illness, the rift between the “real” and the “imagined” life, and the intangibility of memory itself. Collection includes the essays “Into the Snow,” “No … more
Date: May 2011
Creator: Kullberg, Adam
Partner: UNT Libraries
open access

Meta-Analysis of the Impact of After-School Programs on Students Reading and Mathematics Performance

Description: The purpose of this study employing meta-analysis was to assess the impact that after-school programs have on reading and mathematics outcomes. The participants in the primary studies were students in Grades K through 8; years 200 through 2009. The study utilized the theory of change as its theoretical basis. This meta-analysis used the effect size as the standard measure. It began with an overall Cohen's d of .40 for the impact that after-school programs have on reading and mathematics outcome… more
Date: May 2011
Creator: Crawford, Stanley T.
Partner: UNT Libraries
open access

Functions of Quotations in Steven Stucky's Oratorio August 4, 1964 and Their Placements within the Context of a Quotation Continuum: Cultural, Commentary, Remembrance, and Unity

Description: The oratorio August 4, 1964 is a twelve-movement work for orchestra, chorus, and four soloists written by Steven Stucky. The premise for the libretto, adapted by Gene Scheer, is the confluence of two events during one day (August 4, 1964) in the life of Lyndon B. Johnson. Although the main idea of the libretto focuses on these two events of this one day, many cultural references of the 1960's in general can be found as well, such as quotations from the well-known song "We Shall Overcome." Stu… more
Date: May 2011
Creator: Davenport, Jennifer Tish
Partner: UNT Libraries
open access

Integrating Online Discussion Forums into the Foreign Language Curriculum: A Case Study of Advanced Learners of French

Description: This exploratory case study aims to develop a set of best practices for integrating online discussion forums into the foreign language curriculum, focusing specifically on a group of learners in an advanced French grammar course at a large, public U.S. university. During a period of two months, 26 participants completed a series of tasks designed to provide three different types of data: 1) exploration and analysis of interactional, linguistic, and social features of Web forum discourse; 2) par… more
Date: May 2011
Creator: Mbuye, Kanku Lisette
Partner: UNT Libraries
open access

The Biopsychosocial Approach to Understanding, Subtyping, and Treating Depression: Results from the National Comorbidity Survey - Replication.

Description: The most effective and useful way to diagnose and subtype depression has been a long debated topic which even now does not have a definite answer. The biopsychosocial approach to diagnosis may be a solution to this problem by linking various etiologies to symptom presentation. The biopsychosocial model, in regard to depression, takes into account biological risk factors/contributors, psychological or cognitive risk factors/contributors, and social risk factors/contributors to depression when ma… more
Date: May 2011
Creator: McGill, Brittney C.
Partner: UNT Libraries
open access

Structural Validity and Item Functioning of the LoTi Digital-Age Survey.

Description: The present study examined the structural construct validity of the LoTi Digital-Age Survey, a measure of teacher instructional practices with technology in the classroom. Teacher responses (N = 2840) from across the United States were used to assess factor structure of the instrument using both exploratory and confirmatory analyses. Parallel analysis suggests retaining a five-factor solution compared to the MAP test that suggests retaining a three-factor solution. Both analyses (EFA and CFA) i… more
Date: May 2011
Creator: Mehta, Vandhana
Partner: UNT Libraries
open access

Perceptions of Control and Social Support: Correlates of HIV-Related Self-Efficacy

Description: This study examines the extent to which locus of control and social support are linked to self-efficacy with regard to disease management in HIV-positive adults. Perceived ability to effectively manage illness was measured with the Self-Efficacy for Managing Chronic Disease Scale. Scores from the Multidimensional Scale of Perceived Social Support and the Multidimensional Locus of Control Scale were used as predictors. The gender-balanced sample (N = 69) of HIV+ adults was primarily African-Amer… more
Date: May 2011
Creator: Lopez, Eliot Jay
Partner: UNT Libraries
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