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University of Texas Rio Grande Valley

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Globular Cluster Simulations By Mocca Code, Dongming Jin Jul 2014

Globular Cluster Simulations By Mocca Code, Dongming Jin

Theses and Dissertations - UTB/UTPA

The MOCCA code is one of the most advanced codes that has the capacity to simulate a realistic sized star cluster with a full dynamical history including stellar evolution using Monte Carlo methods for the cluster evolution and the Fewbody code for scattering. The dynamical evolution of a cluster can result in the formation of many binary systems. Some of these binaries may be very close. Close double white dwarf binaries (double WDBs) may be promising gravitational wave sources. Our work uses MOCCA to simulate 90 globular clusters with different numbers of stars, binary fractions, metallicities and power-law indices of …

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Isolation And Characterization Of Polychlorinated Biphenyl (Pcb) Degrading Bacteria Isolated From A Pcb Contaminated Reservoir In Donna, Tx, Sergio Cepeda Jul 2014

Isolation And Characterization Of Polychlorinated Biphenyl (Pcb) Degrading Bacteria Isolated From A Pcb Contaminated Reservoir In Donna, Tx, Sergio Cepeda

Theses and Dissertations - UTB/UTPA

The Donna Irrigation System (DIS) located in Donna, Hidalgo County, TX, was confirmed to be contaminated with polychlorinated biphenyls (PCBs) in 1993 and remediation of the site will be attempted in the future. The need to isolate novel PCB degrading bacteria for bioremediation has been an active area of research in recent decades; thus, it was hypothesized that a variety of microorganisms able to degrade PCBs could be isolated from sediments taken from the DIS. Two genes of the PCB degradation pathway, bphA1 and bphC, were detected in 43 bacterial isolates grown from DIS sediments using molecular and culture-based methodology, …

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The Born Approximation, Multiple Scattering, And The Butterfly Algorithm, Alejandro F. Martinez Jul 2014

The Born Approximation, Multiple Scattering, And The Butterfly Algorithm, Alejandro F. Martinez

Theses and Dissertations - UTB/UTPA

Radar works by focusing a beam of light and seeing how long it takes to reflect. To see a large region the beam is pointed in different directions. The focus of the beam depends on the size of the antenna (called an aperture). Synthetic aperture radar (SAR) works by moving the antenna through some region of space. A fundamental assumption in SAR is that waves only bounce once. Several imaging algorithms have been designed using that assumption. The scattering process can be described by iterations of a badly behaving integral. Recently a method for efficiently evaluating these types of integrals …

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The Generation Model Of Internal Waves In A Forced Rotation-Modified Ocean, Daqi Xin Jul 2014

The Generation Model Of Internal Waves In A Forced Rotation-Modified Ocean, Daqi Xin

Theses and Dissertations - UTB/UTPA

A two-layer model which contains the forcing term due to the barotropic tides which flow over a comparatively large bottom topography in the ocean was derived previously. The model can be used to describe the generation of nonlinear dispersive internal tides and the following disintegration into internal waves. We studied the influence of Coriolis effect. A numerical simulation shows that the Earth’s rotation affects the generation of the internal waves since it hampers the disintegration of internal tides into internal waves.

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Radar Image Processing And Its Applications Based On Convolution Back Projection, Qitong Li Jul 2014

Radar Image Processing And Its Applications Based On Convolution Back Projection, Qitong Li

Theses and Dissertations - UTB/UTPA

A general synthetic aperture radar (SAR) signal model is derived from the Maxwell’s equations, and a SAR image processing algorithm called Convolution Back Projection (CBP) will be introduced in this thesis, which can be applied to data gathered by a Synthetic Aperture Radar (SAR) system to produce high resolution images. The purpose of this thesis is starting from Maxwell’s equations to study the CBP algorithm as it is applied to SAR image processing. Two different image simulation results will be provided by this method.

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Studies Of A Mathematical Model For Generating Rhythmic Behavior With A Simple Brain, Juan C. Morales Jul 2014

Studies Of A Mathematical Model For Generating Rhythmic Behavior With A Simple Brain, Juan C. Morales

Theses and Dissertations - UTB/UTPA

The rhythmic behavior of feeding in the pond snail, Lymnaea stagnalis can be described computationally by a model describing its central pattern generator network (CPG). The model includes coupled Hodgkin-Huxley type nonlinear ordinary differential equations describing four neurons connected by both inhibitory and excitatory synapses. We studied the system’s dependence on current parameters to generate periodic behavior. We also considered the effect of eliminating specific connections from the network. In addition, experiments on the biological system were used to motivate application of the model in Parkinson’s disease.

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Using The Differential Fay Identities For Ribbon Graph Enumeration, Indalecio Soto Jr. Jul 2014

Using The Differential Fay Identities For Ribbon Graph Enumeration, Indalecio Soto Jr.

Theses and Dissertations - UTB/UTPA

In this paper we are exploiting connections between the Differential Fay Identities and the partition function of Gaussian Unitary Random Matrices. The partition function has a asymptotic expression whose terms give the generating function for the enumeration of ribbon graphs partitioned by genus. These ribbon graphs (k; j), of k vertices of degree j have an orientation in genus g where the edges are represented as ribbons. Furthermore, we will develop connections between the Differential Fay Identities and introduce several theorems between the hierarchies of the identities. Lastly, we will briefly explore the first Differential Fay Identity that contains the …

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Biodegradable Electrospun Nanofibers Coated With Platelet-Rich Plasma For Cell Adhesion And Proliferation, Luis Diaz-Gomez, Carmen Alvarez-Lorenzo, Angel Concheiro, Maite Silva, Fernando Dominguez, Faheem A. Sheikh, Travis Cantu, Raj Desai, Vanessa L. Garcia, Javier Macossay-Torres Jul 2014

Biodegradable Electrospun Nanofibers Coated With Platelet-Rich Plasma For Cell Adhesion And Proliferation, Luis Diaz-Gomez, Carmen Alvarez-Lorenzo, Angel Concheiro, Maite Silva, Fernando Dominguez, Faheem A. Sheikh, Travis Cantu, Raj Desai, Vanessa L. Garcia, Javier Macossay-Torres

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

Biodegradable electrospun poly(ε-caprolactone) (PCL) scaffolds were coated with platelet-rich plasma (PRP) to improve cell adhesion and proliferation. PRP was obtained from human buffy coat, and tested on human adipose-derived mesenchymal stem cells (MSC) to confirm cell proliferation and cytocompatibility. Then, PRP was adsorbed on the PCL scaffolds via lyophilization, which resulted in uniform sponge-like coating of 2.85 (s.d. 0.14) mg/mg. The scaffolds were evaluated regarding mechanical properties (Young’s modulus, tensile stress and tensile strain), sustained release of total protein and growth factors (PDGF-BB, TGF-β1 and VEGF), and hemocompatibility. MSC seeded on the PRP-PCL nanofibers showed an increased adhesion and proliferation …

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Illustrations And Supporting Texts For Sound Standing Waves Of Air Columns In Pipes In Introductory Physics Textbooks, Liang Zeng, Chris Smith, G. Herold Poelzer, Jennifer Rodriguez, Edgar Corpuz, George Yanev Jul 2014

Illustrations And Supporting Texts For Sound Standing Waves Of Air Columns In Pipes In Introductory Physics Textbooks, Liang Zeng, Chris Smith, G. Herold Poelzer, Jennifer Rodriguez, Edgar Corpuz, George Yanev

School of Mathematical & Statistical Sciences Faculty Publications

In our pilot studies, we found that many introductory physics textbook illustrations with supporting text for sound standing waves of air columns in open-open, open-closed, and closed-closed pipes inhibit student understanding of sound standing wave phenomena due to student misunderstanding of how air molecules move within these pipes. Based on the construct of meaningful learning from cognitive psychology and semiotics, a quasiexperimental study was conducted to investigate the comparative effectiveness of two alternative approaches to student understanding: a traditional textbook illustration approach versus a newly designed air molecule motion illustration approach. Thirty volunteer students from introductory physics classes were randomly …

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Quantization Dimension For Gibbs-Like Measures On Cookie-Cutter Sets, Mrinal Kanti Roychowdhury Jul 2014

Quantization Dimension For Gibbs-Like Measures On Cookie-Cutter Sets, Mrinal Kanti Roychowdhury

School of Mathematical & Statistical Sciences Faculty Publications

In this paper using the Banach limit we have determined a Gibbs-like measure μ h supported by a cookie-cutter set E which is generated by a single cookie-cutter mapping f . For such a measure μ h and r ∈ ( 0 , + ∞ ) we have shown that there exists a unique κ r ∈ ( 0 , + ∞ ) such that κ r is the quantization dimension function of the probability measure μ h , and we established its functional relationship with the temperature function of the thermodynamic formalism. The temperature function is commonly used to …

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Search For Gravitational Waves Associated With Γ-Ray Bursts Detected By The Interplanetary Network, J. Aasi, B. P. Abbott, Mario C. Diaz, S. R. Morriss, Soma Mukherjee, M. E. Normandin, Volker Quetschke, O. Puncken, Malik Rakhmanov, Karla E. Ramirez, Robert Stone Jun 2014

Search For Gravitational Waves Associated With Γ-Ray Bursts Detected By The Interplanetary Network, J. Aasi, B. P. Abbott, Mario C. Diaz, S. R. Morriss, Soma Mukherjee, M. E. Normandin, Volker Quetschke, O. Puncken, Malik Rakhmanov, Karla E. Ramirez, Robert Stone

Physics & Astronomy Faculty Publications

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005–2010 during LIGO’s fifth and sixth science runs and Virgo’s first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search …

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Turbidimetric Determination Of Anionic Polyacrylamide In Low Carbon Soil Extracts, James Jihoon Kang, Tyler D. Sowers, Owen W. Duckworth, Aziz Amoozegar, Joshua L. Heitman, Richard A. Mclaughlin Jun 2014

Turbidimetric Determination Of Anionic Polyacrylamide In Low Carbon Soil Extracts, James Jihoon Kang, Tyler D. Sowers, Owen W. Duckworth, Aziz Amoozegar, Joshua L. Heitman, Richard A. Mclaughlin

School of Earth, Environmental, & Marine Sciences Faculty Publications

Concerns over runoff water quality from agricultural lands and construction sites have led to the development of improved erosion control practices, including application of polyacrylamide (PAM). We developed a quick and reliable method for quantifying PAM in soil extracts at low carbon content by using a turbidimetric reagent, Hyamine 1622. Three high-molecular weight anionic PAMs differing in charge density (7, 20, and 50 mol%) and five water matrices, deionized (DI) water and extracts from four different soils, were used to construct PAM calibration curves by reacting PAM solutions with hyamine and measuring turbidity development from the PAM–hyamine complex. The PAM …

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Methods And Results Of A Search For Gravitational Waves Associated With Gamma-Ray Bursts Using The Geo 600, Ligo, And Virgo Detectors, J. Aasi, B. P. Abbott, H. Daveloza, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, Cristina V. Torres Jun 2014

Methods And Results Of A Search For Gravitational Waves Associated With Gamma-Ray Bursts Using The Geo 600, Ligo, And Virgo Detectors, J. Aasi, B. P. Abbott, H. Daveloza, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, Cristina V. Torres

Physics & Astronomy Faculty Publications

In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz–1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. We introduce the method of a linear search grid to analyze GRB events with large sky localization uncertainties, for example the localizations provided by the Fermi Gamma-ray Burst Monitor (GBM). Coherent searches for gravitational waves (GWs) can be computationally intensive when the GRB sky position is not well localized, due to the corrections required for the difference in arrival time between detectors. …

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Inference Of Snp-Gene Regulatory Networks By Integrating Gene Expressions And Genetic Perturbations, Dongchul Kim, Jiao Wang, Chunyu Liu, Jean Gao Jun 2014

Inference Of Snp-Gene Regulatory Networks By Integrating Gene Expressions And Genetic Perturbations, Dongchul Kim, Jiao Wang, Chunyu Liu, Jean Gao

Computer Science Faculty Publications

In order to elucidate the overall relationships between gene expressions and genetic perturbations, we propose a network inference method to infer gene regulatory network where single nucleotide polymorphism (SNP) is involved as a regulator of genes. In the most of the network inferences named as SNP-gene regulatory network (SGRN) inference, pairs of SNP-gene are given by separately performing expression quantitative trait loci (eQTL) mappings. In this paper, we propose a SGRN inference method without predefined eQTL information assuming a gene is regulated by a single SNP at most. To evaluate the performance, the proposed method was applied to random data …

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A Study Of Hybrid Instructional Delivery For Graduate Students In An Educational Leadership Course, Alejandro Garcia, Jesus Abrego, Meagan M. Calvillo Jun 2014

A Study Of Hybrid Instructional Delivery For Graduate Students In An Educational Leadership Course, Alejandro Garcia, Jesus Abrego, Meagan M. Calvillo

Organization and School Leadership Faculty Publications

This paper describes a qualitative study in which ways to improve instructional delivery for graduate students in an Educational Leadership course in Master of Education program in a predominantly Hispanic university located in South Texas were examined. Questions explored perceptions, attitudes, and reasons for choosing a hybrid instructional delivery model. Five themes emerged from the data: flexibility, assumption of responsibility in learning, emphasis on active learning, building peer relationships, and deepened learning.

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Creating A Seamless Pipeline Into Undergraduate Programs In Stem Fields Through Region-Wide Articulation Agreements, Immanuel Edinbarough, Mikhail M. Bouniaev, Bill W. Elliott Jun 2014

Creating A Seamless Pipeline Into Undergraduate Programs In Stem Fields Through Region-Wide Articulation Agreements, Immanuel Edinbarough, Mikhail M. Bouniaev, Bill W. Elliott

Manufacturing & Industrial Engineering Faculty Publications

Underrepresented minority students pursue science, technology, engineering, and mathematics (STEM) related degrees at much lower rates compared to other segments of the population. To attract minority students, schools with STEM programs have resorted to myriad strategies such as cohorts, scholarships, mentoring, summer bridges, etc. Some schools have also sought innovative ways to develop a pipeline for graduates of two-year technical degree programs to matriculate into their four-year STEM programs and complete the remaining coursework leading to a BAT or BS degree. The University of Texas at Brownsville (UTB) has adopted this latter innovative approach to increasing student enrollment in STEM …

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Solution Of Fractional Harmonic Oscillator In A Fractional B-Poly Basis, Muhammad I. Bhatti Jun 2014

Solution Of Fractional Harmonic Oscillator In A Fractional B-Poly Basis, Muhammad I. Bhatti

School of Mathematical & Statistical Sciences Faculty Publications

An algorithm for approximating solutions to fractional-order differential equations in fractional polynomial basis is presented. A finite generalized fractional-order basis set is obtained from the modified Bernstein Polynomials, where α is the fractional-order of the modified Bernstein type polynomials (B-polys). The algorithm determines the desired solution in terms of continuous finite number of generalized fractional polynomials in a closed interval and makes use of Galerkin method to calculate the unknown expansion coefficients for constructing the approximate solution to the fractional differential equations. The Caputo’s definition for a fractional derivative is used to evaluate derivatives of the polynomials. Each term in …

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The Ninja-2 Project: Detecting And Characterizing Gravitational Waveforms Modelled Using Numerical Binary Black Hole Simulations, J. Aasi, B. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, Mario C. Diaz, Malik Rakhmanov, Joseph D. Romano, Soma Mukherjee, Volker Quetschke, Teviet Creighton, Robert Stone Jun 2014

The Ninja-2 Project: Detecting And Characterizing Gravitational Waveforms Modelled Using Numerical Binary Black Hole Simulations, J. Aasi, B. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, Mario C. Diaz, Malik Rakhmanov, Joseph D. Romano, Soma Mukherjee, Volker Quetschke, Teviet Creighton, Robert Stone

Physics & Astronomy Faculty Publications

The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave (GW) astrophysics communities. The purpose of NINJA is to study the ability to detect GWs emitted from merging binary black holes (BBH) and recover their parameters with next-generation GW observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete BBH hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a ‘blind injection challenge’ similar to that conducted in recent Laser …

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Arecibo Pulsar Survey Using Alfa. Iii. Precursor Survey And Population Synthesis, J. K. Swiggum, D. R. Lorimer, M. A. Mclaughlin, S. D. Bates, D. J. Champion, S. M. Ransom, A. Brazier, J. W.T. Hessels, D. J. Nice, Fredrick A. Jenet Jun 2014

Arecibo Pulsar Survey Using Alfa. Iii. Precursor Survey And Population Synthesis, J. K. Swiggum, D. R. Lorimer, M. A. Mclaughlin, S. D. Bates, D. J. Champion, S. M. Ransom, A. Brazier, J. W.T. Hessels, D. J. Nice, Fredrick A. Jenet

Physics & Astronomy Faculty Publications

The Pulsar Arecibo L-band Feed Array (PALFA) Survey uses the ALFA 7-beam receiver to search both inner and outer Galactic sectors visible from Arecibo (32° ≲ ℓ ≲ 77° and 168° ≲ ℓ ≲ 214°) close to the Galactic plane (|b| ≲ 5°) for pulsars. The PALFA survey is sensitive to sources fainter and more distant than have previously been seen because of Arecibo's unrivaled sensitivity. In this paper we detail a precursor survey of this region with PALFA, which observed a subset of the full region (slightly more restrictive in ℓ and |b| ≲ 1°) …

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Influence Of Age, Sex And Genetic Factors On The Human Brain, D Reese Mckay, Anderson M. Winkler, Rene L. Olvera, Joanne E. Curran, Harald H. H. Goring, Thomas D. Dyer, Ravi Duggirala, Laura Almasy, John Blangero, David C. Glahn Jun 2014

Influence Of Age, Sex And Genetic Factors On The Human Brain, D Reese Mckay, Anderson M. Winkler, Rene L. Olvera, Joanne E. Curran, Harald H. H. Goring, Thomas D. Dyer, Ravi Duggirala, Laura Almasy, John Blangero, David C. Glahn

School of Medicine Publications

We report effects of age, age(2), sex and additive genetic factors on variability in gray matter thickness, surface area and white matter integrity in 1,010 subjects from the Genetics of Brain Structure and Function Study. Age was more strongly associated with gray matter thickness and fractional anisotropy of water diffusion in white matter tracts, while sex was more strongly associated with gray matter surface area. Widespread heritability of neuroanatomic traits was observed, suggesting that brain structure is under strong genetic control. Furthermore, our findings indicate that neuroimaging-based measurements of cerebral variability are sensitive to genetic mediation. Fundamental studies of genetic …

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The Enigma Consortium: Large-Scale Collaborative Analyses Of Neuroimaging And Genetic Data, Paul M. Thompson, Jason L. Stein, Laura Almasy, Anderson M. Winkler, John Blangero, Joanne E. Curran, Ravi Duggirala, Thomas D. Dyer, Harald H. H. Goring, Peter T. Fox Jun 2014

The Enigma Consortium: Large-Scale Collaborative Analyses Of Neuroimaging And Genetic Data, Paul M. Thompson, Jason L. Stein, Laura Almasy, Anderson M. Winkler, John Blangero, Joanne E. Curran, Ravi Duggirala, Thomas D. Dyer, Harald H. H. Goring, Peter T. Fox

School of Medicine Publications

The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging data from over 12,826 subjects. In addition, data from 12,171 individuals were provided by the CHARGE consortium for replication of findings, in a total of 24,997 subjects. By meta-analyzing results from many sites, ENIGMA has detected factors that affect the brain that no individual site could detect on its own, and that require larger …

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Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas May 2014

Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas

School of Earth, Environmental, & Marine Sciences Faculty Publications

Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH) and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT) and its precursor, 5-hydroxytryptophan (5-HTP) as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions …

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Gauging Wetland Restoration Status Using Benthic-Based Structural And Functional Metrics, Claudia Alejandra Tamez May 2014

Gauging Wetland Restoration Status Using Benthic-Based Structural And Functional Metrics, Claudia Alejandra Tamez

Theses and Dissertations - UTB/UTPA

Efforts to restore Bahia Grande, a 2630 hectare, historically sea grass dominated playa lake, are currently underway and describing its current ecological status is critical to recommending any future physical manipulations to the immense basin. A benthic community based study was conducted on three estuaries in Cameron County, Texas (2012 to 2013) in order to compare the polychaete community dynamics and ecosystem productivity rates of the restored basin to that of two older adjacent reference sites (i.e. South Bay and San Martin Lake) in an effort to gauge system status. All three sites were once contiguous with the Lower Laguna …

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A Screening Platform For Identification Of Compounds That Inhibit Protein Synthesis In Pseudomonas Aeruginosa, Yanmei Hu May 2014

A Screening Platform For Identification Of Compounds That Inhibit Protein Synthesis In Pseudomonas Aeruginosa, Yanmei Hu

Theses and Dissertations - UTB/UTPA

Pseudomonas aeruginosa is a Gram-negative pathogenic bacteria and a common cause of nosocomial infections. This pathogen has recently garnered attention due to its pan-resistance. We have developed a poly(U) mRNA-directed aminoacylation/translation (A/T) protein synthesis system from P. aeruginosa. The concentration of each component of the system has been arrived at through multiple rounds of optimization. Poly-phenylalanine synthesis in the system was monitored using scintillation proximity assays (SPA). This system has been used to screen two natural compound libraries (>1100) and a number of the compounds that inhibit greater than 50% of the activity of the system have been identified. …

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Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun May 2014

Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun

Theses and Dissertations - UTB/UTPA

With the depletion of non-renewable resources and the related problems such as environmental pollutions and global warming effect, the society urgently needs more efficient and controllable energy conversion and storage systems. Three-dimensional ZnO nanoforests were prepared and morphology-tunable, which benefits both of energy conversion and storage systems. Willow-like ZnO nanoforests led the highest conversion efficiency of photoelectrochemical water splitting in reported pure ZnO nanostructures. Compared with nanowire arrays, ZnO@MnO2 nanoforests delivered 5 times higher specific capacitances within the same footprint area. V2O5@PPy exhibited higher specific capacitance and better rate stability than pure V2O5 nanofibers. This work lays the foundation for …

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Bicultural Self-Efficacy, Student Achievement, And Persistence Of Mexican American College Students, Richard Kirk May 2014

Bicultural Self-Efficacy, Student Achievement, And Persistence Of Mexican American College Students, Richard Kirk

Theses and Dissertations - UTB/UTPA

This mixed methods study will explore the relationship of bi-cultural self-efficacy with student achievement and persistence for first generation Mexican American students enrolled at a two year college. The Bicultural Self Efficacy Scale for Minority Adults (BISES-MA ) will be used to collect quantitative data from a study group and control group. The study group will participate in a student success course using high engagement strategies developed by Advancement Via Individual Determination for Higher Education (AHE). Analysis of variance will be conducted to determine the degree of difference between the study and control groups on bicultural self-efficacy and student achievement …

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Distributed Formation Tracking Control Of Multiple Car-Like Robots, Chunyu Chen May 2014

Distributed Formation Tracking Control Of Multiple Car-Like Robots, Chunyu Chen

Theses and Dissertations - UTB/UTPA

In this thesis, distributed formation tracking control of multiple car-like robots is studied. Each vehicle can communicate and send or receive states information to or from a portion of other vehicles. The communication topology is characterized by a graph. Each vehicle is considered as a vertex in the graph and each communication link is considered as an edge in the graph. The unicycles are modeled firstly by both kinematic systems. Distributed controllers for vehicle kinematics are designed with the aid of graph theory. Two control algorithms are designed based on the chained-form system and its transformation respectively. Both algorithms achieve …

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An Analytical And Experimental Biosensor For Human Mig Using Algan/Gan Based Hemt Devices, Hector Trevino Ii May 2014

An Analytical And Experimental Biosensor For Human Mig Using Algan/Gan Based Hemt Devices, Hector Trevino Ii

Theses and Dissertations - UTB/UTPA

An amperometric biosensor using AlGaN/GaN based HEMT devices is constructed experimentally and validated through analytical and numerical techniques for detection of a key protein in allograft rejection (Human MIG/CXCL9). The prototype developed provides a reliable sensing platform that will allow label-free and marker-free detection. By exploiting characteristics unique to AlGaN/GaN based HEMT devices, a floating gate configuration is employed to allow reliable sensing without the need for any reference electrode. Self-assembled monolayers (SAM) are formed at the gate surface by using a crosslinker (DSP) to allow for appropriate immobilization of target antibodies. A theoretical analytical and numerical model is developed …

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Is Texas Measuring Up To Federal Expectations? An Examination Of The No Child Left Behind Legislation On Texas Region One Education Service Center District Schools, Maricela De Leon May 2014

Is Texas Measuring Up To Federal Expectations? An Examination Of The No Child Left Behind Legislation On Texas Region One Education Service Center District Schools, Maricela De Leon

Theses and Dissertations - UTB/UTPA

This research paper presented information on student performance results for school children in Texas Region One – Title I district schools. By using recent data on student performance from a seven year period, 2003 to 2010, between district schools in Region One, the findings of the results is reflected to answer the question on whether district schools in Texas Region One –Title I schools reflect the intended No Child Left Behind act performance indicators as identified in the 2002 legislation.

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Manufacture And Characterization Of Silver And Copper Nanostructures Produced Via Forcespun Nylon 6 Nanofibers, Wenqian Zhao May 2014

Manufacture And Characterization Of Silver And Copper Nanostructures Produced Via Forcespun Nylon 6 Nanofibers, Wenqian Zhao

Theses and Dissertations - UTB/UTPA

Nylon 6 nanofibers were produced using the Forcespinning® method and were deposited with silver or copper thin films using the high vacuum thermal evaporation technique for surface functionalization of nanostructures. The changes in surface composition, morphology and surface energy of native and metallic coated Nylon 6 nanofibers were examined. Their antibacterial properties of native, silver or copper coated Nylon 6 nanofibers were tested. Furthermore, the Nylon 6 nanofibers were used as templates in order to obtain silver or copper nanotubes where the polymer was removed after high temperature calcination. The metallic coated Nylon 6 nanofibers and metallic nanotubes morphology and …

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