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Measuring The Impact Of Narrative On Player's Presence And Immersion In A First Person Game Environment, Raul Huerta Aug 2012

Measuring The Impact Of Narrative On Player's Presence And Immersion In A First Person Game Environment, Raul Huerta

Theses and Dissertations - UTB/UTPA

In the virtual environments (VE) literature, presence has been described as the feeling whereby an individual feels as if he or she is actually in the VE. In the videogame literature, the related concept of immersion is viewed as an effect facilitating player engagement. This thesis examines how narrative and graphics quality influence presence and immersion in a first person game. Three levels of narrative and graphics quality are used in an empirical study: text narrative with high quality graphics, no text narrative with high quality graphics, and no text narrative with low quality graphics. Results showed that there is …


Electromagnetic Interference Shielding Effectiveness Of Metallic Thin Films Deposited On High Density Polyethylene And Styrene Butadiene Copolymer Reinforced With Carbon Nanofibers, Horus Garcia Aug 2012

Electromagnetic Interference Shielding Effectiveness Of Metallic Thin Films Deposited On High Density Polyethylene And Styrene Butadiene Copolymer Reinforced With Carbon Nanofibers, Horus Garcia

Theses and Dissertations - UTB/UTPA

Aluminum, Copper and Silver were deposited by thermal evaporation onto Vapor Grown Carbon Nanofiber (VGCNF) reinforced High Density Polyethylene (HDPE) and Styrene Butadiene Copolymer (SBC) composites. Electromagnetic Interference Shielding Effectiveness (EMI SE) was conducted on the structures to analyze the synergistic effect. Characterization was performed by Scanning Electron Microscopy, X-ray Diffraction, and Atomic Force Microscopy. Adhesion test and surface influence on SE were also performed. It was observed that a single layer metallic thin film on carbon nanofiber (CNF) polymer composite experienced a summation of shielding performance. The EMI SE increased with CNF content increase of 10, 15, and 20 …


Synthesis Of Novel Bis-Β-Lactams, Jocabed Marquez Aug 2012

Synthesis Of Novel Bis-Β-Lactams, Jocabed Marquez

Theses and Dissertations - UTB/UTPA

This study presents the synthesis and structure of newly discovered β-lactams and the mechanism of their synthesis via the Staudinger reaction. β-lactams known as 2-azetidinones, are four membered cyclic amides that have been extensively used and recognized as the central motif of the β-lactam antibiotics, the most widely employed family of antimicrobial agent to date. The Staudinger reaction involves the cycloaddition between an acid chloride with an imine, in presence of a tertiary base. The possibility of cooperative effects from two therapeutic functionalities in drug molecules, has prompted interest in the synthesis of Bis-β-lactams. The synthesis of 2 novel Bis-β-lactams …


A Study Of Limited English Proficient Students' Perceptions Of The Effectiveness Of Research-Based Best Practices In Developmental Education Reading Courses At The University Of Texas-Pan American, Mauricio Eugenio De Leon Aug 2012

A Study Of Limited English Proficient Students' Perceptions Of The Effectiveness Of Research-Based Best Practices In Developmental Education Reading Courses At The University Of Texas-Pan American, Mauricio Eugenio De Leon

Theses and Dissertations - UTB/UTPA

The purpose of this study is to assess the research-based best practices instructors at The University of Texas-Pan American (UTPA) implement in their developmental education reading courses, and if these practices effectively address our Mexican, Mexican-American, and Hispanic Limited English Proficient (LEP) population. The data I collected and analyzed for this study consisted of qualitative and quantitative self-evaluation and self- identity questionnaire feedback from students enrolled in developmental education reading courses focusing primarily on the students who are Mexican, Mexican-American, or Hispanic and LEP for the purpose of measuring these students’ perceptions of the teaching practices employed. In order to …


Microwave-Induced Bismuth Nitrate-Catalyzed Multicomponent Reaction Toward Heterocycles, Ashwini Bobbala Aug 2012

Microwave-Induced Bismuth Nitrate-Catalyzed Multicomponent Reaction Toward Heterocycles, Ashwini Bobbala

Theses and Dissertations - UTB/UTPA

The microwave-induced reaction for the synthesis of nitrogen containing heterocyclesis very important in medicinal chemistry. The synthesis of various other valuable compounds is also done by employing this reaction. The aza Diels-Alder reaction is one of the most powerful synthetic tools for the synthesis of nitrogen containing heterocycles. The main goal of the research is to synthesize the nitrogen containing heterocycles using Bismuth nitrate as the catalyst in the presence of microwave irradiation. In the present study we explore the catalytic activity of bismuth nitrate and the role of microwave reactor in the synthesis of 2, 3-diaryl substituted bicyclic octanone …


New Approach To Time Domain Classification Of Broadband Noise In Gravitational Wave Data, Soma Mukherjee, P. Rizwan, R. Biswas Jul 2012

New Approach To Time Domain Classification Of Broadband Noise In Gravitational Wave Data, Soma Mukherjee, P. Rizwan, R. Biswas

Physics & Astronomy Faculty Publications

Transient broadband noise in gravitational wave (GW) detectors-also known as noise triggers (referred to as triggers for brevity)-can often be a deterrant to the efficiency with which astrophysical search pipelines detect sources. It is important to understand their instrumental or environmental origin so that they could be eliminated or accounted for in the data. Since the number of triggers is large, data mining approaches such as clustering and classification are useful tools for this task. Classification of triggers based on a handful of discrete properties has been done in the past. A rich information content is available in the waveform …


Pt-Symmetric Talbot Effects, Hamidreza Ramezani, D. N. Christodoulides, V. Kovanis, I. Vitebskiy, Tsampikos Kottos Jul 2012

Pt-Symmetric Talbot Effects, Hamidreza Ramezani, D. N. Christodoulides, V. Kovanis, I. Vitebskiy, Tsampikos Kottos

Physics & Astronomy Faculty Publications

We show that complex PT-symmetric photonic lattices can lead to a new class of self-imaging Talbot effects. For this to occur, we find that the input field pattern has to respect specific periodicities dictated by the symmetries of the system. While at the spontaneous PT-symmetry breaking point the image revivals occur at Talbot lengths governed by the characteristics of the passive lattice, at the exact phase it depends on the gain and loss parameter, thus allowing one to control the imaging process. © 2012 American Physical Society.


Derivative Couplings With Built-In Electron-Translation Factors: Application To Benzene, Shervin Fatehi, Joseph E. Subotnik Jul 2012

Derivative Couplings With Built-In Electron-Translation Factors: Application To Benzene, Shervin Fatehi, Joseph E. Subotnik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Derivative couplings are the essential quantities at the interface between electronic-structure calculations and nonadiabatic dynamics. Unfortunately, standard approaches for calculating these couplings usually neglect electronic motion, which can lead to spurious electronic transitions. Here we provide a general framework for correcting these anomalies by incorporating perturbative electron-translation factors (ETFs) into the atomic-orbital basis. For a range of representative organic molecules, we find that our ETF correction is often small but can be qualitatively important, especially for few-atom systems or highly symmetric molecules. Our method entails no additional computational cost, such that ETFs are “built-in,” and it is equivalent to a …


Practical Methods For Continuous Gravitational Wave Detection Using Pulsar Timing Data, J. A. Ellis, F. A. Jenet, M. A. Mclaughlin Jul 2012

Practical Methods For Continuous Gravitational Wave Detection Using Pulsar Timing Data, J. A. Ellis, F. A. Jenet, M. A. Mclaughlin

Physics & Astronomy Faculty Publications

Gravitational waves (GWs) are tiny ripples in the fabric of space time predicted by Einstein's general relativity. Pulsar timing arrays (PTAs) are well poised to detect low-frequency (10-9-10-7 Hz) GWs in the near future. There has been a significant amount of research into the detection of a stochastic background of GWs from supermassive black hole binaries (SMBHBs). Recent work has shown that single continuous sources standing out above the background may be detectable by PTAs operating at a sensitivity sufficient to detect the stochastic background. The most likely sources of continuous GWs in the pulsar timing frequency band are extremely …


Discovery Of The Optical/Ultraviolet/Gamma-Ray Counterpart To The Eclipsing Millisecond Pulsar J1816+4510, D. L. Kaplan, Kevin Stovall, S. M. Ransom, M. S. R. Robers, R. Kotulla, Anne M. Archibald, C. M. Biwer, Anthony J. Ford, Fredrick Jenet Jul 2012

Discovery Of The Optical/Ultraviolet/Gamma-Ray Counterpart To The Eclipsing Millisecond Pulsar J1816+4510, D. L. Kaplan, Kevin Stovall, S. M. Ransom, M. S. R. Robers, R. Kotulla, Anne M. Archibald, C. M. Biwer, Anthony J. Ford, Fredrick Jenet

Physics & Astronomy Faculty Publications

The energetic, eclipsing millisecond pulsar J1816+4510 was recently discovered in a low-frequency radio survey with the Green Bank Telescope. With an orbital period of 8.7 hr and a minimum companion mass of 0.16 M☉, it appears to belong to an increasingly important class of pulsars that are ablating their low-mass companions. We report the discovery of the γ-ray counterpart to this pulsar and present a likely optical/ultraviolet counterpart as well. Using the radio ephemeris, we detect pulsations in the unclassified γ-ray source 2FGL J1816.5+4511, implying an efficiency of ∼25% in converting the pulsar's spin-down luminosity into γ-rays and adding PSR …


Negative-Order Korteweg–De Vries Equations, Zhijun Qiao, Engui Fan Jul 2012

Negative-Order Korteweg–De Vries Equations, Zhijun Qiao, Engui Fan

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, based on the regular Korteweg–de Vries (KdV) system, we study negative-order KdV (NKdV) equations, particularly their Hamiltonian structures, Lax pairs, conservation laws, and explicit multisoliton and multikink wave solutions thorough bilinear B¨acklund transformations. The NKdV equations studied in our paper are differential and actually derived from the first member in the negative-order KdV hierarchy. The NKdV equations are not only gauge equivalent to the Camassa-Holm equation through reciprocal transformations but also closely related to the Ermakov-Pinney systems and the Kupershmidt deformation. The bi-Hamiltonian structures and a Darboux transformation of the NKdV equations are constructed with the aid …


Fourier Transform Infrared Spectroscopy And Wide-Angle X-Ray Scattering: Investigations On Polypropylene-Vapor-Grown Carbon Nanofiber Composites, Mircea Chipara, John Hamilton, Alin Cristian Chipara, Tom George, Dorina M. Chipara, Elamin Ibrahim, Karen Lozano, David J. Sellmyer Jul 2012

Fourier Transform Infrared Spectroscopy And Wide-Angle X-Ray Scattering: Investigations On Polypropylene-Vapor-Grown Carbon Nanofiber Composites, Mircea Chipara, John Hamilton, Alin Cristian Chipara, Tom George, Dorina M. Chipara, Elamin Ibrahim, Karen Lozano, David J. Sellmyer

Physics & Astronomy Faculty Publications

Fourier transform infrared (FTIR) spectroscopy and wide-angle X-ray scattering (WAXS) investigations of isotactic polypropylene (iPP)-vapor-grown carbon nanofiber (VGCNF) composites containing various amounts of VGCNFs ranging between 0 and 20 wt %. are reported. The FTIR investigations were focused on the regularity bands of iPP. The FTIR data indicated a drop in the isotacticity index as the concentration of nanofibers was increased; this suggested a decrease in the crystallinity. WAXS measurements revealed a dominating α 1 phase, with a small admixture of γ phase or mesophase. The loading of the polymeric matrix with carbon nanofibers (CNFs) did not induce significant changes …


Utpa Commencement – Summer 2012, University Of Texas-Pan American Jul 2012

Utpa Commencement – Summer 2012, University Of Texas-Pan American

Edinburg Archives - Legacy Commencement Programs

No abstract provided.


Los Arcos - Spring / Summer 2012, University Of Texas-Pan American Jul 2012

Los Arcos - Spring / Summer 2012, University Of Texas-Pan American

UTPA Archives - Los Arcos Magazine

No abstract provided.


A Study Of A High Performing, High Poverty Elementary School On The Texas-Mexico Border, Cynthia Iris Lopez Jul 2012

A Study Of A High Performing, High Poverty Elementary School On The Texas-Mexico Border, Cynthia Iris Lopez

Theses and Dissertations - UTB/UTPA

Transforming low performing schools to ensure the academic success of Hispanic children situated in poverty remains an educational challenge. External factors impacting student learning are often targeted as the main reasons for poor academic achievement, thereby advancing the culturally deficit model. This study is about an elementary school that defied the deficit model as evidenced by its distinguished academic accolades. This instrumental qualitative case study examined a high performing elementary school on the Texas-Mexico Border in which high poverty Hispanic students made dramatic increases in academic achievement. Data were collected from interviews, observations, documents, and other media. Findings for the …


Bypassing The Bandwidth Theorem With Pt Symmetry, Hamidreza Ramezani, J. Schindler, F. M. Ellis, Uwe Günther, Tsampikos Kottos Jun 2012

Bypassing The Bandwidth Theorem With Pt Symmetry, Hamidreza Ramezani, J. Schindler, F. M. Ellis, Uwe Günther, Tsampikos Kottos

Physics & Astronomy Faculty Publications

The beat time τ fpt associated with the energy transfer between two coupled oscillators is dictated by the bandwidth theorem which sets a lower bound τ fpt∼1/δω. We show, both experimentally and theoretically, that two coupled active LRC electrical oscillators with parity-time (PT) symmetry bypass the lower bound imposed by the bandwidth theorem, reducing the beat time to zero while retaining a real valued spectrum and fixed eigenfrequency difference δω. Our results foster design strategies which lead to (stable) pseudounitary wave evolution, and may allow for ultrafast computation, telecommunication, and signal processing. © 2012 American Physical Society.


Microwave-Assisted Polystyrene Sulfonatecatalyzed Synthesis Of Novel Pyrroles, Rosario Astrid Vargas Cardenas, Blanca Olinda Quintanilla Leal, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik Jun 2012

Microwave-Assisted Polystyrene Sulfonatecatalyzed Synthesis Of Novel Pyrroles, Rosario Astrid Vargas Cardenas, Blanca Olinda Quintanilla Leal, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Background: Pyrroles are widely distributed in nature and important biologically active molecules. The reaction of amines with 2,5-dimethoxytetrahydrofuran is a promising pathway for the synthesis of pharmacologically active pyrroles under microwave irradiation.

Results: Microwave-induced polystyrenesulfonate-catalyzed synthesis of pyrroles from amines and 2,5- diemthoxytetrahydrofuran has been accomplished with excellent yield. This method produces pyrroles with polyaromatic amines.

Conclusion: The present procedure for the synthesis of N-aromatic substituted pyrroles will find useful application in the area of pharmacologically active molecules.


All-Sky Search For Gravitational-Wave Bursts In The Second Joint Ligo-Virgo Run, J. Abadie, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano Jun 2012

All-Sky Search For Gravitational-Wave Bursts In The Second Joint Ligo-Virgo Run, J. Abadie, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration -1s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining …


Knowledge, Skills, And Dispositions Influencing Middle School Teachers' Decision Making In Planning Social Studies Instruction In A Hispanic Serving School, Angela Gonzalez Jun 2012

Knowledge, Skills, And Dispositions Influencing Middle School Teachers' Decision Making In Planning Social Studies Instruction In A Hispanic Serving School, Angela Gonzalez

Theses and Dissertations - UTB/UTPA

The issue of highly qualified teachers as the key to improving the educational system in the United States has become a primary focus in education. The federal educational policy No Child Left Behind Act 2001, describes what it means to be a highly qualified teacher in core subject areas, and all states are required to use this criterion for defining what teachers should know, and be able to do. Accordingly, certified teachers in today’s public school classrooms must possess the knowledge, skills, and dispositions so that all students, including those students who have been historically disadvantaged and those who are …


Detecting Gravitational Wave Memory With Pulsar Timing, J. M. Cordes, F. A. Jenet Jun 2012

Detecting Gravitational Wave Memory With Pulsar Timing, J. M. Cordes, F. A. Jenet

Physics & Astronomy Faculty Publications

We compare the detectability of gravitational bursts passing through the solar system with those passing near each millisecond pulsar in an N-pulsar timing array. The sensitivity to Earth-passing bursts can exploit the correlation expected in pulse arrival times while pulsar-passing bursts, though uncorrelated between objects, provide an N-fold increase in overall time baseline that can compensate for the lower sensitivity. Bursts with memory from mergers of supermassive black holes produce step functions in apparent spin frequency that are the easiest to detect in pulsar timing. We show that the burst rate and amplitude distribution, while strongly dependent on inadequately known …


Upper Limits On A Stochastic Gravitational-Wave Background Using Ligo And Virgo Interferometers At 600-1000 Hz, J. Abadie, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya D. Mohanty, Volker Quetschke, Joseph D. Romano Jun 2012

Upper Limits On A Stochastic Gravitational-Wave Background Using Ligo And Virgo Interferometers At 600-1000 Hz, J. Abadie, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya D. Mohanty, Volker Quetschke, Joseph D. Romano

Physics & Astronomy Faculty Publications

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600–1000 Hz, we obtained a 95% upper limit on the amplitude of ��GW⁡(��)=��3⁡(��/900  Hz)3, of ��3<0.32, assuming a value of the Hubble parameter of ℎ100=0.71. These new limits are a factor of seven better than the previous best in this frequency band.


Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan Jun 2012

Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The risk of bioterrorism events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. This report describes nanoenergetic gas generators (NGG) system that exhibit long term stability and superior release of biocidal substances for destruction of pathogenic bacteria. The effect of iodine vaporization on destroying of Escherichia coli (E-coli, HB101 K-12 strain) by using expressing Green Fluorescent Protein (GFP) was investigated. HB101 K-12 has been genetically modified to prevent its growth unless grown on an enriched medium. To obtain quantitative data we used pGLO transformation …


Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, T. Benjamin Zhan, T. Edwin Chow, J. Gaines Wilson Jun 2012

Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, T. Benjamin Zhan, T. Edwin Chow, J. Gaines Wilson

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Background: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005.

Methods: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality …


Imperfect Detection Of Tax Evasion In A Corrupt Tax Administration, Diego Escobari May 2012

Imperfect Detection Of Tax Evasion In A Corrupt Tax Administration, Diego Escobari

School of Economics and Finance Faculty Publications

This article models the imperfect detection of tax evasion motivated by the existence of a corrupt tax administration. Consistent with previous literature, fines and audit probabilities both have a positive effect on compliance. Moreover, the model shows that they have a negative effect on the bribes paid to corrupt tax officials. More corruption decreases compliance levels, giving honest auditors incentives to work harder to detect evasion. Giving inspectors a share of the detected evasion (tax farming) makes auditors work harder; however, increasing their wages reduces their exerted effort to discover evasion. Higher compliance can as well be achieved by hiring …


First Low-Latency Ligo+Virgo Search For Binary Inspirals And Their Electromagnetic Counterparts, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, Matthew Benacquista, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano May 2012

First Low-Latency Ligo+Virgo Search For Binary Inspirals And Their Electromagnetic Counterparts, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, Matthew Benacquista, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

Aims. The detection and measurement of gravitational-waves from coalescing neutron-star binary systems is an important science goal for ground-based gravitational-wave detectors. In addition to emitting gravitational-waves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to the gravitational-wave emission. A joint detection of the gravitational-wave and electromagnetic signals would provide a powerful new probe for astronomy. Methods. During the period between September 19 and October 20, 2010, the first low-latency search for gravitational-waves from binary inspirals in LIGO and Virgo data was …


Search For Gravitational Waves From Intermediate Mass Binary Black Holes, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano May 2012

Search For Gravitational Waves From Intermediate Mass Binary Black Holes, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range 100-450M and with the component mass ratios between 11 and 41. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the intermediate mass black holes mergers as a function of the component masses. In the most efficiently detected bin centered on 88+88M, for nonspinning sources, the rate density …


Polyvinylchloride-Single-Walled Carbon Nanotube Composites: Thermal And Spectroscopic Properties, Mircea Chipara, Jessica Cruz, Edgar R. Vega, Jorge Alarcon, Thomas Mion, Dorina M. Chipara, Elamin Ibrahim, Steven C. Tidrow, David Hui May 2012

Polyvinylchloride-Single-Walled Carbon Nanotube Composites: Thermal And Spectroscopic Properties, Mircea Chipara, Jessica Cruz, Edgar R. Vega, Jorge Alarcon, Thomas Mion, Dorina M. Chipara, Elamin Ibrahim, Steven C. Tidrow, David Hui

Physics & Astronomy Faculty Publications

Nanocomposites of single-walled carbon nanotubes dispersed within polyvinylchloride have been obtained by using the solution path. High-power sonication was utilized to achieve a good dispersion of carbon nanotubes. Thermogravimetric analysis revealed that during the synthesis, processing, or thermal analysis of these nanocomposites the released chlorine is functionalizing the single-walled carbon nanotubes. The loading of polyvinylchloride by single-walled carbon nanotubes increases the glass transition temperature of the polymeric matrix, demonstrating the interactions between macromolecular chains and filler. Wide Angle X-Ray Scattering data suggested a drop of the crystallite size and of the degree of crystallinity as the concentration of single-walled carbon …


The Collegian (2012-05-07), Rene Cardona Jr. May 2012

The Collegian (2012-05-07), Rene Cardona Jr.

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 64, No. 30


Self-Determination, Success, And College Readiness Of First Generation Students In A Higher Education Institution, Manuel Ochoa May 2012

Self-Determination, Success, And College Readiness Of First Generation Students In A Higher Education Institution, Manuel Ochoa

Theses and Dissertations - UTB/UTPA

The purpose of the study was to describe and compare if self-determination factors differed in first and non-first generation college students and success levels. Additionally, comparisons of college readiness levels were measured, and finally a measure of factors that contribute to college success based in first and second semester grade point averages were investigated using multiple linear regression analysis. Using a Self-Determination Theory framework of human motivation, helps identify a basic psychological need for autonomy as a central feature for understanding effective regulation and well-being (Moller, Ryan, & Deci, 2006). The target population in this study was 1,586 returning students …


Border Hispanics’ Physical Activity Improvement In A Chronic Disease Prevention Program, Lu Xu May 2012

Border Hispanics’ Physical Activity Improvement In A Chronic Disease Prevention Program, Lu Xu

Theses and Dissertations - UTB/UTPA

In seeking of effective prevention programs to improve physical activities, we want to examine the factors related to physical activities improvement in Alliance for a Healthy Border, a chronic disease prevention program with pre-post-post evaluations through 12 federally qualified community health centers serving primarily Hispanics in communities along the U.S.- Mexico border. Logistic regression was performed to examine the association between physical activity and twenty predictors at baseline. Multinomial regression was used to examine the determinants of physical activities improvement at two time points: program end and post six-months. Socio-demographic, baseline health condition factors, and determination of doing physical activity …