Digital Commons Network^™

Laguna Madre Estuary Program Environmental Strategic Plan - Final Report, Kim D. Jones, Lucy Camacho, T. Sinha, Omar Al-Qudah, Hudson R. Deyoe, Augusto Sanchez Gonzalez, Jungseok Ho, Javier Guerrero

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

The goal of this effort is to establish a framework of fundamental information and critical ideas to serve as a basis to assist in supporting legislation to found the 29th National Estuary Program for the Laguna Madre of the Gulf coast of Texas.

The National Estuary Program (NEP) was established by the Clean Water Act Amendments of 1987 (Section 320) to protect nationally significant estuaries threatened by development, pollution and overuse. The U.S. Environmental Protection Agency administers the NEP. The Corpus Christi Bay NEP (now the Coastal Bend Bays and Estuary Program) was among the last estuaries accepted into the …

Particulate Metal Exposures Induce Plasma Metabolome Changes In A Commuter Panel Study, Chandresh N. Ladva, Rachel Golan, Donghai Liang, Roby Greenwald, Douglas I. Walker, Amit U. Raysoni, Vilinh Tran, Tianwei Yu, W. Dana Flanders, Gary W. Miller

School of Earth, Environmental, & Marine Sciences Faculty Publications

Introduction

Advances in liquid chromatography-mass spectrometry (LC-MS) have enabled high-resolution metabolomics (HRM) to emerge as a sensitive tool for measuring environmental exposures and corresponding biological response. Using measurements collected as part of a large, panel-based study of car commuters, the current analysis examines in-vehicle air pollution concentrations, targeted inflammatory biomarker levels, and metabolomic profiles to trace potential metabolic perturbations associated with on-road traffic exposures.

Methods

A 60-person panel of adults participated in a crossover study, where each participant conducted a highway commute and randomized to either a side-street commute or clinic exposure session. In addition to in-vehicle exposure characterizations, participants …

Epigenetics, Heritability And Longitudinal Analysis, Haakon E. Nustad, Marcio Almeida, Angelo J. Canty, Marissa Leblanc, Christian M. Page, Phillip E. Melton

School of Medicine Publications

Background

Longitudinal data and repeated measurements in epigenome-wide association studies (EWAS) provide a rich resource for understanding epigenetics. We summarize 7 analytical approaches to the GAW20 data sets that addressed challenges and potential applications of phenotypic and epigenetic data. All contributions used the GAW20 real data set and employed either linear mixed effect (LME) models or marginal models through generalized estimating equations (GEE). These contributions were subdivided into 3 categories: (a) quality control (QC) methods for DNA methylation data; (b) heritability estimates pretreatment and posttreatment with fenofibrate; and (c) impact of drug response pretreatment and posttreatment with fenofibrate on DNA …

Research Symposium - Health Disparities 2018: Closing The Gap, The University Of Texas Rio Grande Valley. School Of Medicine

School of Medicine Publications

With the theme of “Health Disparities: Closing the Gap,” this symposium aims to showcase the work done by researchers here in the Valley and beyond toward improving the health and well-being of the communities they serve and society as a whole.

Mechanical And Sorptivity Characteristics Of Edge-Oxidized Graphene Oxide (Eogo)-Cement Composites: Dry- And Wet-Mix Design Methods, Yousef Alharbi, Jinwoo An, Byoung Hooi Cho, Mohammad Khawaji, Wonseok Chung, Boo Hyun Nam

Civil Engineering Faculty Publications

This paper aims to investigate the effects of edge-oxidized graphene oxide nanoflakes (EOGO) on the mechanical properties and sorptivity of cement composites. The EOGO used in this study was produced by a mechanochemical process that assists the production of EOGO in large quantities at significantly reduced costs, enabling its practical use for infrastructure construction. The scope of this work includes the use of EOGO as an additive in cement composites, including cement paste and mortar. This study explores two mixing methods: The dry-mix method and the wet-mix method. The dry-mix method uses EOGO as dry powder in cement composites whereas …

The Rider (2018-09-03), Victor G. Ramirez

The Rider Archives

Vol.4 No.2

Mapping Opposition In The Sonora- Arizona Borderlands: A Critical Recovery Of Federico Ronstadt’S Memoir Borderman, Diana Noreen Rivera

Literatures and Cultural Studies Faculty Publications

Federico Ronstadt’s Borderman, a memoir written between 1944 and 1954, recounts the businessman’s immigration to Tucson and his life in the Sonora- Arizona borderlands during the late nineteenth and early twentieth centuries. Paradigms of opposition that inform the recovery of early Mexican American memoir and autobiography—centering the life writings of elite, dispossessed Mexican Americans and Hispanic immigrant literature written in Spanish—have discouraged study of Ronstadt’s English-language, seemingly assimilationist memoir. In my critical recovery of Borderman, I argue that it should be read as part of the legacy of oppositional literature written by people of Mexican descent in the …

Use Of The Wilshire Equations To Correlate And Extrapolate Creep Data Of Hr6w And Sanicro 25, Vito Cedro Iii, Christian Garcia, Mark Render

Mechanical Engineering Faculty Publications

Advanced power plant alloys must endure high temperatures and pressures for durations at which creep data are often not available, necessitating the extrapolation of creep life. Many methods have been proposed to extrapolate creep life, and one of recent significance is a set of equations known as the Wilshire equations. With this method, multiple approaches can be used to determine creep activation energy, increase the goodness of fit of available experimental data, and improve the confidence level of calculating long-term creep strength at times well beyond the available experimental data. In this article, the Wilshire equation is used to extrapolate …

Development Of Hurricane Storm Surge Model To Predict Coastal Highway Inundation For South Texas, Sara E. Davila, Adan Garza, Jungseok Ho

School of Earth, Environmental, & Marine Sciences Faculty Publications

Forecasting areas prone to flooding will allow us to send off our information gathered to departments such as TxDOT and the United States Department of Transportation. This would then enable these departments to create appropriate evacuation routes, depicting which roads are clear and which cannot be used in the event of a storm. Simulating hurricanes that have passed through this area such as Dolly in 2008, Beulah in 1967, and Bret in 1999 will display the roads and federal highways that frequently tend to get flooded. Identifying the “danger roads” and which federal highways will ultimately be useful for various …

A Non-Parametric Approach To Testing The Axioms Of The Shapley Value With Limited Data, Victor H. Aguiar, Roland Pongou, Jean-Baptiste Tondji

School of Economics and Finance Faculty Publications

The unique properties of the Shapley value–efficiency, equal treatment of identical input factors, and marginality–have made it an appealing solution concept in various classes of problems. It is however recognized that the pay schemes utilized in many real-life situations generally depart from this value. We propose a non-parametric approach to testing the empirical content of this concept with limited datasets. We introduce the Shapley distance, which, for a fixed monotone transferable-utility game, measures the distance of an arbitrary pay profile to the Shapley pay profile, and show that it is additively decomposable into the violations of the classical …

Underwater Adhesive Using Solid–Liquid Polymer Mixes, Alin Cristian Chipara, T. Tsafack, P. S. Owuor, J. Yeon, C. E. Junkermeier, A. C. T. Van Duin, S. Bhowmick, S. A. S. Asif, S. Radhakrishnan, Mircea Chipara

Physics & Astronomy Faculty Publications

Instantaneous adhesion between different materials is a requirement for several applications ranging from electronics to biomedicine. Approaches such as surface patterning, chemical cross-linking, surface modification, and chemical synthesis have been adopted to generate temporary adhesion between various materials and surfaces. Because of the lack of curing times, temporary adhesives are instantaneous, a useful property for specific applications that need quick bonding. However, to this day, temporary adhesives have been mainly demonstrated under dry conditions and do not work well in submerged or humid environments. Furthermore, most rely on chemical bonds resulting from strong interactions with the substrate such as acrylate …

Three-Dimensional Carbon Nanotube Yarn Based Solid State Solar Cells With Multiple Sensitizers Exhibit High Energy Conversion Efficiency, Glenn Grissom, Jared Jaksik, Monica Mcentee, Erin M. Durke, Sayeeda Tj Aishee, Margaret Cua, Okenwa Okoli, Ahmed Touhami, H. Justin Moore, M. Jasim Uddin

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

Fiber-type dye sensitized solar cells that are non-metallic, flexible, and thread-like in structure have many potential military and functional textile applications. With the use of quantum dots (QD), exciton transfer facilitators (Phenyl-C61-butyric acid methyl ester-PCBM) and Poly(3-hexylthiophene-2,5-diyl-P3HT), and careful preparation of the TiO2 oxide layer deposited on the carbon fiber working electrode, an optimized efficiency of 7.6% was obtained. Carbon nanotube yarn (CNTY) was used to prepare both the working and counter electrodes of the fabricated cells. TiCl4 annealing of the TiO2 layer was carried out and the resulting oxide layer morphology was found to be very uniform. The quantum …

Conformational Analysis Of A Taddol-Based Phosphoramidite P,N Ligand In A Palladium(Ii) Η3-Π-Allyl Complex, Tülay A. Ateşin, Abdurrahman Atesin, Oscar Rodriguez, Diego Rivera, Lohany Y. Garcia

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

Highlights

• Two lowest energy conformers differ in allyl conformation, conformer with exo allyl having lower energy.

• Lowest energy conformer has “chair” conformation of 7-membered ring and “edge-on/face-on/face-on/edge-on” array of pH groups.

• Next lowest energy conformer with exo allyl has alternating “edge-on/face-on” arrangement and “twist” 7-membered ring.

• Changes in “chair/twist” conformations with different substrates is possible due to 2.4 kcal/mol energy difference.

• These results explain stereochemical outcome of the reaction, and will guide design of new catalysts.

Abstract

The most stable conformations of a TADDOL-based phosphoramidite P,N ligand coordinated to a palladium(II) η3-π-allyl fragment have been investigated using …

Removal Of Cu2+ And Ni2+ From Aqueous Solution Using Sno2 Nanomaterial Effect Of: Ph, Time, Temperature, Interfering Cations, Abigail M. Zepeda, Daisy Gonzalez, Luis Gonzalez Heredia, Karina Marquez, Cesar Perez, Erika Pena, K. Flores, Carolina Valdes, Thomas Eubanks, Jason Parsons, J. Cantu

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

Tin oxide, SnO2, nanomaterial was synthesized and tested for the removal of Cu2+ and Ni2+ ions from aqueous solutions. Various parameters for the binding were investigated in batch studied, which included pH, time, temperature, and interferences. In addition, isotherm studied were performed to determine the maximum binding capacity for both Cu2+ and Ni2+ ions. The optimal binding pH determined from the effects of pH were to be at pH 5 for both the Cu2+ and Ni2+ ions. The isotherm studies were performed at temperatures of 4°C, 25 °C, and 45 °C for both the Cu2+ and Ni2+ ions and were …

Industrial Structure And Political Outcomes: The Case Of The 2016 Us Presidential Election, Thomas Ferguson, Paul D. Jorgensen, Jie Chen

Political Science Faculty Publications

This paper analyzes the US presidential election of 2016, examining the patterns of industrial structure and party competition in both the major party primaries and the general election. It attempts to identify the new, historically specific factors that led to the upheavals, especially the steady growth of a “dual economy” that locks more and more Americans out of the middle class. It draws extensively on a newly assembled, more comprehensive database to identify the specific political forces that coalesced around each candidate, including the various stages of the Trump campaign.

What Makes People Actually Embrace Or Shun Mobile Payment: A Cross-Culture Study, Yali Zhang, Jun Sun, Zhaojun Yang, Ying Wang

Information Systems Faculty Publications

Mobile payment is becoming increasingly popular, but it encounters the resistance from certain user groups. This study examines the factors that influence both the technology acceptance and actual usage aspects of mobile payment adoption from the perspective of the general systems theory. Based on a literature review, it conceptualizes the embedding relationships among relevant behavioral processes, personal characteristics, and extrinsic factors and develops a research model. Together, the extrinsic factors in terms of culture, subjective norm, and socioeconomic status and main personal characteristics including demographics, personality traits, and past behavior are hypothesized to have direct and moderating effects on mobile …

Solution Of Mathematical Model For Gas Solubility Using Fractional-Order Bhatti Polynomials, Muhammad I. Bhatti, Paul Bracken, Nicholas Dimakis, Armando Herrera

School of Mathematical & Statistical Sciences Faculty Publications

Solutions of a mathematical model for gas solubility in a liquid are attained employing an algorithm based on the generalized Galerkin B-poly basis technique. The algorithm determines a solution of a fractional differential equation in terms of continuous finite number of generalized fractional-order Bhatti polynomial (B-poly) in a closed interval. The procedure uses Galerkin method to calculate the unknown expansion coefficients for constructing a solution to the fractional-order differential equation. Caputo?s fractional derivative is employed to evaluate the derivatives of the fractional B-polys and each term in the differential equation is converted into a matrix problem which is then inverted …

Functionalized And Nanostructured Fibers For Photocatalysis And Energy Conversion, Jared R. Jaksik

Theses and Dissertations

Fiber-type / flexible materials present a unique opportunity for the incorporation of photocatalytic / energy generating technology, as they typically have a broad surface area exposed to light (clothing, curtains, carpet). In this work, several methods of harvesting incident light striking a flexible substrate to perform useful work are examined. In the first section a gold and silver nanoparticle augmented TiO2 thin film textile coating is evaluated for its self-cleaning / UV-protective / anti-microbial properties, and stability of the film / substrate over time is examined. In the second section a dye sensitized / hybrid type solar cell architecture based …

Characterizing Polychlorinated Biphenyl Degradation Potential In Surface Water Bacteria From Rio Grande Valley, Texas Reservoirs, Alisha M. Janiga

Theses and Dissertations

The Donna Reservoir in Donna, Texas is contaminated with polychlorinated biphenyl (PCB) pollution. This reviews the current understanding of PCBs and investigate the potential of PCB degradation by native bacteria communities in the Donna Reservoir. The metabolic diversity, biphenyl tolerance, bphA1 presence were tested on surface water samples from the Donna Reservoir. The Ecoplate data suggest that the communities have a diverse metabolic capacity and the degree of plant life may interact with carbon type metabolism but not the rate of growth. Biphenyl growth curves showed that all the samples from the Donna Reservoir are tolerant to the average PCB …

Children's Physical Fitness And Academic Performance: A Challenge For Leaders In Title I Schools In The Rio Grande Valley, Maricela Valdez

Theses and Dissertations

The purpose of this quantitative study was to examine the relationship between physical fitness, body mass index and academic performance in Hispanic children enrolled in grade 5 from a district in the Rio Grande Valley. A total of 547 participants were selected from 11 elementary schools from a school district in the Rio Grande Valley. The dependent variable, academic performance, was measured by children’s gain score on the STAAR Progress Measure for Reading and Math assessments. The independent variables of physical fitness were measured by scores on cardiovascular fitness and body mass index from the FITNESSGRAM assessment.

The literature review …

Environmental Conditions In San Martin Lake: Effects Of Eutrophication In An Estuary Associated With The Laguna Madre, Wendy L. Rogers

Theses and Dissertations

San Martin Lake is a shallow water Estuary in the lower Laguna Madre off the Port of Brownsville Shipping channel. It is influenced both by incoming tides and waste water runoff both from local farms and the Brownsville water treatment plants. The resulting mixture of eutrophic water and incoming sea water creates the perfect mix for a potential algal bloom. This study looks at the nutrient levels and environmental conditions in the main basin of the estuary to establish baseline levels and to observe the rate of nutrient clearing being accomplished in this environment. As sport recreation in the area …

Improvement Of Soil Structure Through Organic Crop Management, Conservation Tillage And Grass-Clover Ley, Viviana Loaiza Puerta, Engil Isadora Pujol Pereira, Raphaël Wittwer, Marcel G. A. Van Der Heijden, Johan Six

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• Organic crop management combined with reduced tillage improved soil structure.
• The ley period improved soil structure for conventional intensive tillage.
• The ley period increased total carbon in organic crop management at 0–6 cm soil depth.

Abstract

Conventional intensive tillage is a widespread soil management practice that controls weeds and promotes nutrient mineralization at the expense of a degraded soil structure and soil carbon (C) loss. Alternative soil management practices such as no tillage, reduced tillage and temporary leys, however, can minimize the negative effects of intensive tillage on soil structure. To improve understanding of these management practices on …

Underrepresentation Of Hispanic Bilingual Students In Gifted And Talented Programs: The Role Of Teacher Expectations, Melissa I. Leon Leal

Theses and Dissertations

There is currently an underrepresentation of Hispanic and bilingual students in Gifted and Talented (GT) programs. The present study examines the role of teachers’ expectations and preconceptions of what constitutes a gifted student as possible contributing factors to the underrepresentation of Hispanic and bilingual students in GT programs. Participants will include approximately 100 pre-service teachers and currently practicing teachers in the community. Measures will include a demographic survey, vignettes for identifying giftedness which describe bilingual and monolingual potential gifted students across three ethnic groups, and a survey about student qualities that includes both quantitative and qualitative items. Results and implications …

A Formulation Of L-Isothermic Surfaces In Three-Dimensional Minkowski Space, Paul Bracken

School of Mathematical & Statistical Sciences Faculty Publications

The Cartan structure equations are used to study space-like and time-like isothermic surfaces in three-dimensional Minkowski space in a unified framework. When the lines of curvature of a surface constitute an isothermal system, the surface is called isothermic. This condition serves to define a system of one-forms such that, by means of the structure equations, the Gauss-Codazzi equations for the surface are determined explicitly. A Lax pair can also be obtained from these one-forms for both cases, and, moreover, a nonhomogeneous Schrödinger equation can be associated with the set of space-like surfaces.

Glutathione: A Small Molecule With Big Sense, Cristina E. Raya, Debasish Bandyopadhyay

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

Glutathione, a peptide found in microbes, plants and animals including human plays a key role in maintaining healthy cells. The peptide exists in both reduced and oxidized forms. Synthesis of GSH occurs in the cytosol of cells, and the extent of glutathione synthesis relies on various factors, such as amino acid availability, protein activity etc. Once synthesized, glutathione exists in both forms: oxidized (GSSG) and reduced (GSH). Oxidized glutathione characterized by its disulfide linkage. On the other hand, presence of a thiol group characterizes the reduced glutathione. This thiol makes the tripeptide an essential component of health; it makes glutathione …

Nannochloris Sp. And Oocystis Sp. Algae Exposed To Osmotic Stress For Increased Lipid Production For Use In Biofuels, Laura M. Chavez

Theses and Dissertations

Algal biofuel research is important due to the potential need for replacement of non-renewable fossil fuels and a changing global climate. Under stress, algal cells tend to increase neutral lipid production, which are a suitable source for biofuels. The goal of this study was to subject Nannochloris sp.. and Oocystis sp. algal cells to osmotic stress by modifying sucrose and salinity levels in different treatment medias.

The treatment containing the lowest salinity (15 ppt) and no sucrose yielded the highest lipid fluorescence/cell in Nannochloris sp.. cells (0.00142 ± 0.00044) on day 2 while the treatment containing highest salinity (35ppt) …

Linguistics In Secondary Education: Teachers' Perceptions Of Linguistics In The Classroom, Ayla Aizza Galvan

Theses and Dissertations

Theoretical linguistics is an area of English study focusing on the abstract components of language: phonology, morphology, syntax, semantics, and pragmatics. By 11th and 12th grade, students in the United States have been tested on linguistic concepts, as per state examination standards. English Language Arts teachers can introduce theoretical linguistic investigation and terms to their students, but this is not happening. The paper reviews why theoretical linguistic analysis is not thoroughly implemented in classrooms, successful classroom linguistic investigation in other countries and some U.S., and how linguistic investigation can be part of classroom curriculum. The research incorporates survey data from …

Effect Of Molten Salt Synthesis Processing Duration On The Photo- And Radioluminescence Of Uv- Visible- And X-Ray-Excitable La 2 Hf 2 O 7 :Eu 3+ Nanoparticles, Jose P. Zuniga, Santosh K. Gupta, Maya Abdou, Yuanbing Mao

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

Ln 3+ -ion-doped nanomaterials possess excellent properties because of their high color purity, longer excited state lifetime, narrow emission, and large Stokes shifts. In this work, we studied the correlation between the luminescence properties of La 2 Hf 2 O 7 :Eu 3+ pyrochlore nanoparticles (NPs) synthesized by a molten salt synthesis (MSS) method at a relatively low temperature and several MSS processing durations (from 1 to 12 h). We synthesized these NPs with different sizes just by changing the MSS processing time without subjecting to high temperature. Raman spectroscopy confirmed the stabilization of the ideal pyrochlore structure of the …

Asymmetric Free-Space Light Transport At Nonlinear Metasurfaces, Nir Shitrit, Jeongmin Kim, David S. Barth, Hamidreza Ramezani, Yuan Wang, Xiang Zhang

Physics & Astronomy Faculty Publications

Asymmetric light transport has significantly contributed to fundamental science and revolutionized advanced technology in various aspects such as unidirectional photonic devices, optical diodes, and isolators. While metasurfaces mold wave fronts at will with an ultrathin flat optical element, asymmetric transport of light cannot be fundamentally achieved by any linear system including linear metasurfaces. We report asymmetric transport of free-space light at nonlinear metasurfaces upon transmission and reflection. Moreover, we theoretically derive the nonlinear generalized Snell's laws that were experimentally confirmed by the anomalous nonlinear refraction and reflection. The asymmetric transport at optically thin nonlinear interfaces is revealed by the concept …

Aluthge Transforms Of 2-Variable Weighted Shifts, Raul E. Curto, Jasang Yoon

School of Mathematical & Statistical Sciences Faculty Publications

We introduce two natural notions of multivariable Aluthge transforms (toral and spherical), and study their basic properties. In the case of 2-variable weighted shifts, we first prove that the toral Aluthge transform does not preserve (joint) hyponormality, in sharp contrast with the 1-variable case. Second, we identify a large class of 2-variable weighted shifts for which hyponormality is preserved under both transforms. Third, we consider whether these Aluthge transforms are norm-continuous. Fourth, we study how the Taylor and Taylor essential spectra of 2-variable weighted shifts behave under the toral and spherical Aluthge transforms; as a special case, we consider the …