Digital Commons Network^™

Gulf Trade Networks And Family Ties: French Migration Via New Orleans To The Lower Rio Grande Valley, 1848-1881, Kristen D. Kline

Theses and Dissertations

This thesis considers economic and social aspects of French immigration to the Lower Rio Grande Valley (LRGV) of Texas during the mid-nineteenth century, with special emphasis on a small group of merchants who left France during the 1850s. It synthesizes the work of several scholars who have focused on French presence in the LRGV with others who have analyzed various economic facets of the LRGV during different periods between the eighteenth and twentieth centuries. This study attempts to situate five families into the context of nineteenth-century European migration to the Americas, as well as into the Gulf maritime economy on …

Enabling High Quality Oxygen Measurements During Robotic Based Studies Of Ocean Ecological And Biogeochemical Processes, Brianna A. Alanis

Theses and Dissertations

Dissolved oxygen is an essential parameter necessary for understanding marine ecological and biogeochemical processes. New robotic vehicles and autonomous platforms are being applied to an even wider range of ecological and biogeochemical studies. Thus, arises the opportunity for matching the best possible oxygen sensing techniques and methods to these new platforms. In so doing, we can enable both more targeted and higher resolution oxygen measurements than previously possible and potentially use oxygen measurements for a wider range of applications, including in situ incubation experiments and primary productivity measurements. This thesis tested three different oxygen sensors in a trade study for …

Application Of Solar Water Heaters For Industrial Use, Lucas T. Atkins

Theses and Dissertations

Solar water heating is a technology that is mainly used for domestic water heating in residential homes. In most applications, the idea is to make a home “off the grid” in that there is no requirement for outside infrastructure or need for energy utility to provide power to this home. This falls in line with the trend of “going green” in an effort to reduce energy use, increase efficiency, or reduce emissions and other harmful byproducts.

This technology can be adapted to reduce the energy costs of industrial manufacturing plants. By eliminating the need for certain sections of a process …

Characterization Of Plasmids Harbored By Vibrio Cholerae Isolates Endemic To The Rio Grande Delta, Viviana Trevino

Theses and Dissertations

Cholera is a diarrheal disease responsible for considerable morbidity and mortality globally. Epidemics along the Rio Grande Delta were reported during the 1850s, and the etiological agent Vibrio cholerae, remains endemic, thus presenting a unique opportunity for a study of historical and biological relevance. V. cholerae strains were isolated from two locations: the Rio Grande River under a bridge linking Brownsville to Matamoros (site 21) and where the river empties into the Gulf of Mexico (site 42). Two strains from site 21, and one from site 42 were selected to isolate, subclone, sequence, assemble and annotate extra-chromosomal elements. Results …

Genetic Determinants Of Variation In The Gh/Igf-1 Axis And Their Relationship To Cardiometabolic Health, Rafael Luis Aguirre Guillen

Theses and Dissertations

Background: In a study of Mexican Americans, we performed analyses of GEI and pleiotropy in the axis in relation to MS. GH/IGF-1 axis components were studied. Model parameters and likelihoods were estimated by maximum likelihood.

Results: Pleiotropy was observed for IGFBP3 (p

Conclusions: IGF-I and IGFBP3 are genetically correlated with MS whereas MS influences the additive genetic variance in IGFBP1 variables mainly but also in IGF-I somewhat by virtue of the VH exhibited by IGF-I/IGFBP1.

The Role Of Sediment Resuspension In Estuarine Inorganic Nutrient Cycling, Kirsten Jo Ayres

Theses and Dissertations

Time-scaling of estuarine inorganic nitrogen cycling contains many assumptions due to biogeochemical interactions. Nitrogen, often a limiting factor for primary production, is transformed and utilized by many estuarine organisms. Inorganic nitrogen is especially high in porewater. High nutrient pore water, contained within the interstitial spaces of sediment, has been assumed to influx high concentrations of inorganic nutrients into surface waters during resuspension events. These short-term resuspension events rapidly introducing high concentration of nutrients into the water column. In order to determine the internal time scale of inorganic nitrogen cycling, a box-model nutrient budget, horizontal in situ transects, and vertical nutrient …

Graphene-Fibers Hybrid Structures As Adsorbents For Heavy Metal Ions In Aqueous Solutions, Dulce C. Capitanachi

Theses and Dissertations

The project focuses on the study of graphene-fiber hybrid structures for adsorption of heavy metal ions in aqueous solutions. Polyvinyl alcohol-based graphene–fiber structures were created using centrifugal spinning and a carbonization process.

Characterization methods of the graphene–fiber hybrid structures (GFHS) include SEM, FTIR, TGA, and EDX. Single-step batch-type adsorption studies were performed to analyze the interaction of Cu (II) and Pb (II) ions onto GFHS surface. Different heavy metal ion concentrations were used, as well as a variation of pH values. Elemental analysis of the adsorbent’s surface after filtration experiments was studied by EDX and spectroscopy to verify the presence …

Learning To Detect Pedestrians By Watching Videos, Andrew Y. Chen

Theses and Dissertations

The field of deep learning has experienced a resurgence in the recent years, particularly resulting with the advent of AlexNet. Supervised learning is currently the most common and practical machine learning method. The struggle with employing supervised learning to approach problems is that it requires training data. Sufficient training data is correlated with performance for deep learning models. The issue is that preparing the training data can be a tedious and labor intensive task, especially on a large scale. The purpose of this paper is to determine how efficient a machine can learn when trained on automatically annotated data. The …

Understanding College Readiness Through The Framework For Success In Postsecondary Writing: An Analysis Of Algebra Writing In High School, Gabriel Cerda

Theses and Dissertations

The topic of college readiness in the United States has become increasingly important as the number of students entering post-secondary institutions has continued to increase. Along with efforts to increase college readiness for students in K-12, calls have been made to better define what it means to be college ready and understand what factors play a role in preparing students for a postsecondary education. This study uses the Framework for Success in Postsecondary Writing as a critical lens and method of analysis to understand how the Framework can broaden our understanding of college readiness. This is a mixed methods study …

Viability Of Wetland Crops For Use In Treatment Wetlands: Nitrogen Removal From Water And Production Of Food, Andrew Denson Corder

Theses and Dissertations

Treatment wetlands are used to treat wastewater from a variety of sources, but their functionality depends on the macrophytes present therein. To better understand the viability of wetland macrophytes both as sources of food and as agents of nitrogen removal from wastewater, this study quantified plant growth, food production, and nitrogen removal capacity of three common wetland crops as well as three locally dominant graminoid species in a variety of relevant ecological contexts. All six plant species and a control were grown over a ten-week period in three related experiments: (1) under three moisture regimes, (2) with or without competition …

Assessing The Rehabilitation Status Of The Reflooded Bahia Grande, Texas Based On Trace Gas Fluxes, Benthic Macroinvertebrates, And Fish Community Data Along Salinity And Seagrass Gradients, Catherine M. Eckert

Theses and Dissertations

The Bahia Grande is a 6,500-acre tidal basin located at the southernmost tip of Texas. Tidal flow into this coastal estuary was cut off by construction projects in the 1930s, causing the basin to dry up for ~70 years. In 2005, a pilot channel was built to reconnect the estuary to tidal waters, allowing the basin to refill. However, the pilot channel, in addition to other barriers within the basin, do not allow for adequate tidal exchange, leading to intermittent, extreme hypersalinity. Presumably because of the extreme hypersalinity in parts of the Bahia Grande, seagrass beds, which play vital roles …

To Love The Birds And The Places They’Ve Made Their Home: Poems From The Magic Valley, Alyssa B. Garza

Theses and Dissertations

The theme of the collection could be summed up in these lines written by Caryll Houselander in The Reed of God, “body and soul together give glory to God: the sharper the capacity for sorrow and joy, the greater the hallowing...Christ laid hold of the world with His human hands...He wed Himself to it. Our life is the response of the bride” (66–67). Our loving connection to every human person is our loving connection to Christ—charity is our bride-ness. The poems follow one bride through her journey, with the author’s environment (the Rio Grande Valley) coloring the verses, as …

Design And Testing Of A Modular Laser System With Laser Machining And Bioprinting Capabilities, Jesus Gonzalez

Theses and Dissertations

This thesis introduces the applications of ultrafast lasers while focusing on their bioprinting capabilities. A custom system was designed to utilize a femtosecond laser for 2D and 3D applications. The characteristics of lasers allow them to be efficiently used in machining, 3D printing, research, and more. Their power and precision allow them to be used for delicate work such as bioprinting. Bioprinting is a field holding great potential to benefit society. Studies conducted over the years prove its usefulness in printing cells and biomaterials, while showing there is still much to improve upon before being able to print fully functioning …

Association Between Lifetime Adverse Events, Emotion Dysregulation, Posttraumatic Stress Symptoms, Acculturation, And Chronic Pain: A Moderated Mediation Model, Miriam El-Haj

Theses and Dissertations

The association between traumatic experiences and chronic pain is well established. Lesser is known about how acculturation might affect this relation, specifically with Hispanics. In the present study, self-report measures on traumatic experiences, posttraumatic stress symptoms, emotion dysregulation, chronic pain, and acculturation were administered to 140 participants (71.4% females) aged 18–65 years old (M = 35.06, SD = 11.55), to determine whether acculturation moderates the relation between adverse lifetime experiences and chronic pain as mediated by posttraumatic stress symptoms and emotion dysregulation.

Those who were highly acculturated to the U.S. Anglo culture were higher on chronic pain than those who …

The Digital Reading Experiences Of Middle School Readers: A Phenomenological Study, Laura A. Hayward

Theses and Dissertations

Reading digitally is part of the 21st century New Literacies, residing in the curriculum as a comprehension skill developed with print reading skills. Differences exist between purpose of digital reading and print reading, manifested in the association of digital reading as a mostly non-fiction genre, the immediacy to digital information and its relevance to a reader’s decision about the usefulness of the information. Contrastingly, print reading can be fiction or non-fiction with access to all the text. The differences suggest that learning focused on immediate evaluation, synthesis, and application of information while reading digitally should be taught in the context …

Comparison Of Rl Algorithms For Learning To Learn Problems, Adolfo Gonzalez Iii

Theses and Dissertations

Machine learning has been applied to many different problems successfully due to the expressiveness of neural networks and simplicity of first order optimization algorithms. The latter being a vital piece needed for training large neural networks efficiently. Many of these algorithms were produced with behavior produced by experiments and intuition. An interesting question that comes to mind is that rather than observing and then designing algorithms with beneficial behaviors, can these algorithms be learned through a reinforcement learning by modeling optimization as a game. This paper explores several reinforcement learning algorithms which are applied to learn policies suited for optimization.

Histological Evidence Of Annual And Lunar Reproductive Rhythms Of Atlantic Sea Urchin, Arbacia Punctulata In The Gulf Of Mexico: Changes In Nutritive Phagocytes In Relation To Gametogenesis, Eleazar Hernandez Ii

Theses and Dissertations

Environmental phenomena such as temperature, photoperiod, tidal cycle, and lunar rhythm act as external cues that stimulate the reproductive activity of marine organisms. In this study, I report the annual and lunar reproductive cycles, and changes in nutritive phagocytes (NPs) in relation to gonadal maturation of Atlantic sea urchin (Arbacia punctulata, a primeval species). Monthly and weekly changes in gonadal development/maturation were observed histologically. In male, the testicular lobules were densely packed with sperm from June to August. In female, on the other hand, mature eggs first appeared in some ovaries in May, numerically increased from June to …

Cultural Clashes And Cultural Bridges: My Story In Afghanistan, Joe A. Hinojosa Jr.

Theses and Dissertations

Narrative inquiry and grounded theory are the methodology used to tell the story of the researcher’s experiences in Afghanistan. This entailed identifying and researching a process of storytelling and weaving experiences together into a coherent and meaningful whole. The narrative inquiry method is appropriate for this project because the critical sources of data consist of the researcher’s perceptions and experiences in Afghanistan, as reported in the form of narrative stories. This qualitative analysis focuses on examining and interpreting concrete pieces of evidence, formulating quantitative analysis along with sharing personal and professional experiences. To that end, external resources, including letters and …

Constructing Associative Rings From Certain Hypergroups, Oscar Gonzalez

Theses and Dissertations

Tight hypergroups give rise to associative rings if the so-called general normality condition holds\cite{ARTICLE:1}. We consider four examples of tight hypergroups which do not satisfy the general normality condition and show that they still give rise to associative rings. Our examples are HM332(24),HM10353(32), HM10933(32) and HM10941(32)[1].

Evaluation Of The Most Significant Factors Influencing The Production Rates Of Highway Construction Activities, Angelica M. Neira

Theses and Dissertations

The utilization of realistic production rates is key for the accurate estimation of the contract time in highway projects. Several factors have an impact on production rates and change the total duration of construction projects. To organize and complete projects in a timely, quality and financially responsible manner, projects need to be scheduled carefully. Schedulers and planners of the Texas Department of Transportation (TxDOT) have been noticing that the estimated timelines are far from the reality and want to investigate if external factors can be the cause of this discrepancy. Some of the factors considered in this study are the …

Educator Perspectives Of High-Stakes Testing In An Urban School District In Deep South Texas, Sergio R. Garcia

Theses and Dissertations

The purpose of this study was to explore how the high-stakes testing setting and the state assessments have influenced elementary teachers and other school professionals’ approach to preparing students for standardized tests. Policymakers and the public see standardized tests as simple quantifiable measures of school quality and student learning. They assume that high stakes tests will influence teachers and students to try harder and that the results will be used rationally to benefit all students.

Fredrick Herzberg’s Motivation-Hygiene Theory was used as a framework for this research. Study participants included nine experienced elementary school educators in a large urban district …

Non-Space: The Perception Of Reality, Carlos Limas

Theses and Dissertations

This is a formal study of real-world images that try to convey a clear approach to the way we look and relate to unexpected places that at first glance don’t exist in a metaphorical way or just don’t strike us as interesting or attractive. There’s no particular story to tell only the need to expose a different kind of beauty through my own personal subjective view and sensitivity expanding the criteria of my own esthetic values and context of a captured image in a particular scenario.

The perception of Non-Space relates directly to a well establish photography technique called Deadpan, …

Shattering Taciturnity: The Use Of Visual Arts As A Method Of Communication And Expression, Jesmil M. Maldonado Rodriguez

Theses and Dissertations

Silence an action that conceals a person’s memories, thoughts, emotions, fears, and insecurities, making them crave a method of expression. In this case, the Visuals Arts serves as an approach to investigate, create, understand, accept, and confront the darkness within the artist's psychological and emotional state. Inspiration taken from vibrant colors and insects found within Puerto Rico's natural sources, how these interact, relate, and consume the human within. By creating a series of artworks, the artist starts to comprehend how silence has taken over her life. Taciturnity has become the flame that ignited the artistic flow that leads to the …

Photocatalytic Degradation Of Simazine Under Visible Light Using Zinc Oxide/Molybdenum Disulfide Heterostructures, Alexandria Castillo

Theses and Dissertations

The photocatalytic degradation of simazine under visible light by using ZnO/MoS2 heterostructures was investigated. Reaction parameters studied to optimize simazine degradation included pH, loading mass of the photocatalyst, and percentage of MoS2 in the heterostructure. pH 2 was the optimal environment for the degradation reaction of all catalysts. A loading mass of 20 mg for each of the ZnO/MoS2 photocatalysts was determined to be the most effective for in the degradation process. The degradation reactions were observed to follow 2nd order kinetics for all photocatalysts at all temperatures. Band gap studies confirmed a lower energy than that of pure ZnO …

The Acute Effects Of Warm-Up With And Without Blood Flow Restriction Cuffs On Lower Body Temperature, Flexibility, And Vertical Jump Power, Phillipe Thomas Lopez

Theses and Dissertations

Purpose: The purpose of this study was to determine the effect of blood flow restriction warmups (BFR-WU) on skin temperature (ST), range of motion (ROM), and vertical jump (VJ) performance.

Methods: Forty-seven participants performed WU’s with unilateral BFR application. Each participant took part in five different WU durations. Measurements of ST, ROM, VJ were taken at baseline, post-WU, and post-8min.

Results: Significant conditions main effect (p<0.05), condition*time (p<0.05), WUduration*condition (p<0.01), and conditions*time*sex interactions (p<0.05) were found by repeated measures ANOVA.

Conclusion: The current findings reveal that BFR-WU’s react differently throughout time, when compared to NBFR-WU, for ST and VJ performance, but not ROM. The length of duration was only significant …

Genetics And Morphology Of Invasive Tubastraea Species Within The Gulf Of Mexico: A Case Study Of Species Misidentification And Distribution, Amelia E. Mcclure

Theses and Dissertations

The invasive corals, Tubastraea coccinea and Tubastraea micrathus, are known to thrive in reefs within the Gulf of Mexico (GOM). Many studies have indicated that species within this genus are spreading throughout the western Atlantic due to their successful invasion on degraded and artificial reef systems. In the Northern GOM, artificial reefs have been created from decommissioned oil rigs and sunken vessels to provide a hard substrate for coral growth. Although, this method is demonstrating success, it is also facilitating, the dispersal of undesired species. The species, T. coccinea and T. micranthus, were thought to be the only …

Investigating The Use And Effectiveness Of The Istation Advanced Reading Program With Fourth-Grade At-Risk Struggling Readers, Andres Martinez

Theses and Dissertations

The purpose of this study is to investigate the effects of computer-based-instruction (CBI) and multimedia when used as an intervention with upper elementary students experiencing reading difficulties on the State of Texas Assessment of Academic Readiness (STAAR) Reading Assessments. The researcher employed a quantitative, causal-comparative research design for this study. A Texas supplemental reading program, the Istation Advanced Reading Program, was used as a Response to Intervention (RTI) for those at-risk students of failing their Reading STAAR Test in the fourth grade and to sustain an effective reading program district-wide.

Archived data was collected from three South Texas Title I …

Coming To An Understanding: Daoist Rhetoric As Dialogue In Composition Studies, Veronica Anzaldua

Theses and Dissertations

Monological argumentation, based on Aristotelian principles, dominates composition pedagogy in the United States. With this model, students construct arguments in which they advocate for their own viewpoints. To make argumentation more dialogic, there exist various discourse models, including Daoist rhetoric, based on the ancient Chinese philosophy of Daoism. Its tenets have the potential to generate dialogic discourse in composition due to Laozi’s, Zhuangzi’s, and Sunzi’s principles. The recent cultural turn in composition studies opens space for the exploration of dialogic pedagogy. Dialogic pedagogies based on Daoist philosophies, with other recent pedagogical innovations, have the potential to promote deep, interconnected dialogue …

A Sinking Feeling: The Fate Of Concrete Pyramids Deployed In Artificial Reefs In The Texas Gulf Of Mexico, Cameron J. Moody

Theses and Dissertations

The deployment of 2,611 concrete pyramids in Texas gulf waters represents a significant undertaking. In collaboration with Texas Parks and Wildlife, bathymetric sidescan data was collected at three reefs hit by Hurricane Harvey from 2017 to 2019. All reefs lost significant pyramid height between 2017 and 2019. The pyramids demonstrated greater subsidence in the year when Harvey occurred and minimal subsidence the following year. Pyramids that moved outside the reefs were due to hurricane forces and shrimp trawl activity. Pyramids that remained inside the reef remained at their deployment location for two reefs. The pyramids remaining in the third reef …

The Correlation Among Metabolic Syndrome Risk Factors, Hemodynamics, And Arterial Elasticity In Hispanic College Students, Paloma J. Mendoza

Theses and Dissertations

PURPOSE: The purpose of this study was to determine the correlation among MetS risk factors, hemodynamics, and arterial elasticity in Hispanic students attending The University of Texas Rio Grande Valley.

RESULTS: Systolic blood pressure (SBP), diastolic blood pressure (DBP), and fasting glucose (GLU) were the only components of MetS that had a significant correlation with large arterial elasticity (SPB: males: -.477 and females: -.503; DBP: females: -.300; p

CONCLUSION: MetS risk factors significantly correlated with both arterial elasticity and hemodynamic components. Uniquely in this population, waist circumference and systemic vascular resistance was reversely associated.