Physical Sciences and Mathematics Commons^™

Dispersal And Population Structure Of Euchlanis Chihuahuaensis Via Anemochory In The Chihuahuan Desert, Tristan Chavez-Poeschel

Open Access Theses & Dissertations

Desert ecosystems present challenges for aquatic organisms as habitats are fragmented, both in space and time; however, diapausing stages of rotifers can travel hundreds of kilometers during wind events. I used the rotifer Euchlanis chihuahuaensis as a model species to investigate the influence of wind dispersal on gene flow and population genetics in Chihuahuan Desert populations. I hypothesized that anemochory facilitates gene flow from source populations in the Northern Chihuahuan Desert in Mexico and the western United States to habitats in the Trans-Pecos region via delineated wind corridors. To test this hypothesis, the genetic diversity of populations from both inside …

Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham

Open Access Theses & Dissertations

The landscape of central Texas is shaped by over one billion years of Earth's history. An array of lithology lies within central Texas along with two large geological structures. The Llano Uplift, characterized by Proterozoic metamorphic and igneous rocks dating back to 1.37 billion years ago, is encircled by Paleozoic and Mesozoic sedimentary rocks. To the southeast of the Llano Uplift lies the Balcones Fault Zone (BFZ), an extensional structural system of mostly normal faults that delineates the transition between Paleozoic-Mesozoic sedimentary rocks and Cenozoic sedimentary cover, which are influential to the regional hydrogeology. This study investigates the hydrogeological dynamics …

Resource Scarcity Caused By Environmental Changes: Driving Factor In Terrorism Attacks In Afghanistan, Pakistan, Syria, Amaris Bustamante

Open Access Theses & Dissertations

Climate change, resource scarcity, and terrorist attacks are ever-growing crises that disproportionately impact different states. They are crises that can impact the stability and resilience of humanity in the following decades if they are not addressed and mitigated. This study addresses the impact of resource scarcity caused by climate change that can then serve as a driving force in terrorist attacks in climate-sensitive and conflict-prone states. The objective of this mixed-methods study is to identify the correlation between climate changes that lead to resource scarcity such as rainfall and surface temperatures with terrorist attacks when taking into consideration other demographic, …

Water Sufficiency For Organismal Function In Dryland Critical Zones, Lindsey Dacey

Open Access Theses & Dissertations

Water availability is crucial for organismal survival and growth in dryland environments, affecting both ecological interactions and carbon dynamics. The goal of this thesis is to develop soil water release curves (SWRCs) that link soil water potentials (Ψ) to soil water content (θ). Using the SWRCs, temporal soil water sufficiency curves are developed, which quantify the amount of time that dryland critical zones have enough water to sustain the physiology of organisms. These curves allow for effectively indicating water availability across different species, coverage types, and soil conditions, enhancing our understanding of water dynamics in drylands and contributing important parameters …

Assessing Urban Tree Coverage Along The U.S.-Mexico Border: A Gis Analysis Of Paso Del Norte, Melanie Escobar

Open Access Theses & Dissertations

In recent years, researchers have extensively studied the spatial distribution of social demographics and urban tree canopy (UTC) in urban cities, but very few, to this date, address U.S.-Mexico border cities. To date, there is no research that assesses the distribution of urban tree canopy (UTC) in the city of El Paso, Texas, and Ciudad Juarez, Chihuahua, along the U.S.- Mexico border. Leveraging advanced mapping techniques and GIS tools, the study performs comparisons between countries (Juárez vs. El Paso urbanized areas and intra-country (within each country). It compares land cover classifications, assesses variations in UTC distribution across census tracts and …

Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero

Open Access Theses & Dissertations

This study employs a combination of theoretical and experimental analysis to spectroscopically investigate the biomechanistic structure relationship and therapeutic effects of the Nordihydroguaiaretic Acid (NDGA) chemical derived from the Larrea Tridentata plant. These relationships are crucial for understanding NDGA's efficacy in disease prevention, treatment, and potential toxicological effects. While the medicinal and antiviral properties of the NDGA have been studied extensively, there remains a gap in optically identifying and reporting its structural changes. The current research successfully reveals evident trends in NDGA's vibrational signatures, particularly highlighting the absence of the Raman feature at 780 〖cm〗^(-1) as indicative of a fully …

Promoting Social Sustainability: Implementing A Dynamic Stem Driven Framework To Empower Underrepresented Communities In West Texas Schools, Raquel Haggerty

Open Access Theses & Dissertations

This dissertation explores how environmental engineering can utilize STEM education as a strategic tool, enhancing social sustainability and thereby empowering underserved Hispanic communities in West Texas. Responding to significant educational and resource disparities, this research introduces an innovative interdisciplinary framework that combines instruction-initiated resource activation (I2RA), culturally attuned parent engagement (CAPE), and community- centered STEM education (CCSE). This approach uniquely addresses the challenges faced by these communities, integrating environmental solutions with educational advancements to forge a path toward equitable STEM access and achievement.

Additionally, the "Elevate and Empower" case study exemplifies the practical application of this comprehensive framework, demonstrating its …

Analyzing The Impact Of Oil And Gas-Contaminated Fluids On Soil In Eddy And Lea Counties Using Sequential Extraction, Mary Adu-Gyamfi

Open Access Theses & Dissertations

The study investigates the impacts of oil and gas-contaminated fluids on soil within the context of Eddy and Lea Counties in New Mexico, the United States. The increase in oil and gas operations has led to enormous wastewater production that is handled, stored, and transported, leading to thousands of spills yearly. The continuous and accidental release of this wastewater poses several risks to the environment due to its high levels of hazardous pollutants. Several studies were conducted on how to reduce the contaminants; however, the impact caused on the environment and the fate of the spilled fluids is unclear due …

Predictive Understanding Of Lake Water Temperature And Dissolved Oxygen Profiles Across The Red River Basin Through Interpretable Machine Learning, Isabela Suaza Sierra

Open Access Theses & Dissertations

Accurately predicting lake water temperature (LWT) and dissolved oxygen (DO) is crucial for determining threshold values of fish survivability under warmer global conditions, with recreational fishing in reservoirs significantly contributing to regional economies, such as $779 million and $1,891 million annually to the economies of Oklahoma and Texas, respectively. Current mathematical models for temperature and oxygen profiles, which incorporate multi-layer and turbulent mixing equations, are complex and challenging to parameterize, particularly due to uncertainties in acquiring sufficient data for training and validation. Leveraging the flexibility and information extraction power of machine learning (ML) methods, this master thesis aimed to set …

Activity Patterns Of Whiptail Lizards (Aspidoscelis) Found In The Northern Chihuahuan Desert, Guillermo Alvarez

Open Access Theses & Dissertations

Traditional lizard pitfall traps were modified to allow organisms to escape, while collecting valuable ecological data. Modified camera traps were capable of detecting the same species as traditional traps in a semi-arid environment, without posing the associated mortality risks. Pitfall-camera traps were used to sample the activity of the Side-blotched Lizard (Uta stansburiana) and the Southwestern Fence Lizard (Sceloporus cowlesi) in an urban wetland during four continuous years. Evaluations on activity pattern and the activity overlap between the two species revealed extensive overlap, with minor but significant seasonal shifts mediating coexistence. Traps were also effective at detecting other reptiles, invertebrates, …

Addressing Binational Issues For Water Quality Along The United States-Mexico Border And The Use Of The 1944 Water Treaty As A Means For Developing Transboundary Aquifer Agreements, Gilbert Anaya

Open Access Theses & Dissertations

The water resources of the United States (U.S.) and Mexico are under tremendous pressure due to declining reservoir levels, changes in climate, and prolonged drought. The U.S.-Mexico border region relies on the Rio Grande and Colorado River, and shared groundwater resources that are transboundary in nature. These resources are vital to the U.S.-Mexico border and are susceptible to drought that leads to reduced flow and allocation to the users. In addition, there are impacts to water quality caused by return flows and from failing sanitation infrastructure. In this study, we focus on 1) the contribution of springs in an area …

Diverse Impacts Of Commercial Ev Charging Load Infrastructure On Electric Power Grid, Antonio Avila

Open Access Theses & Dissertations

With the rising prominence of electric vehicles (EVs) in the transportation sector, this thesis delves into the critical nexus between commercial EVs, charging infrastructure, and their consequential impacts on the power grid. As commercial EVs, particularly medium and heavy-duty variants, gain traction as viable alternatives in the commercial transportation landscape, understanding the intricacies of their charging requirements becomes paramount. This thesis critically examines the technological and logistical dimensions of the charging infrastructure for supporting commercial EVs, evaluating the consequential implications on the power grid and proposing strategies for mitigation through the utilization of Distributed Energy Resources (DERs). In tandem with …

Evaluation Of Evapotranspiration Estimates Using An Existing Hybrid Machine Learning Model In A Natural And A Managed Dryland Site, Katya Esquivel Herrera

Open Access Theses & Dissertations

Evapotranspiration (ET) is a critical component of the hydrologic cycle, encompassing both evaporative water loss from surfaces and transpiration through plant stomata. The environmental factors influencing ET include water and energy availability, atmospheric capacity for water uptake, and various meteorological variables. ET serves as a unique climate variable linking water, energy, and carbon cycles. In agroecosystems, accurate ET quantification is vital for optimizing water use efficiency, irrigation management, and crop yield. Traditional methods for ET estimation involve direct measurements and indirect models, with both presenting limitations.

Recent years have witnessed the integration of remote sensing and machine learning (ML) algorithms …

Bitcoin's Technical Foundation And Its Potential For A Decentralized And Environmentally Friendly Future, Iqtiar Md Siddique

Open Access Theses & Dissertations

This research examines a systematic analysis of Bitcoin, employing a Coefficient of Variation (CV) approach to gauge its degree of decentralization. Bitcoin, an innovative decentralized digital currency, has received much attention for its potential to revolutionize traditional financial systems. This study employs the Coefficient of Variation (CV) to acquire insights into the wealth distribution and concentration among Bitcoin users. This research demonstrates how decentralized the network of Bitcoin is. The methodology uses real data on Bitcoin addresses and their holdings to compute the Coefficient of Variation (CV). This approach provides valuable insights into the ongoing discourse surrounding Bitcoin's decentralization, offering …

Using Stable Water Isotopes And Radiogenic Strontium Isotopes To Trace Water And Its Salinity Sources In Pecos And Colorado River Basins In Texas, Nuria Valeria Andreu Garcia

Open Access Theses & Dissertations

Water stable isotope ratios (Deuterium/hydrogen 2H/1H and Oxygen 18O/16O ratios) and radiogenic strontium isotope ratios (87Sr/86Sr) have been widely used to trace various hydrologic processes and understand surface-groundwater interactions for watershed and critical zone studies. Our project aimed to trace the water and salinity sources in the Colorado and Pecos Rivers, two major rivers that provide essential water resources for water-stressed parts of Texas. In our study, we collected water samples from 25 locations during July (monsoon season), December 2021 (dry season), and May 2022 (pre-monsoon season) along the Pecos and Colorado rivers from central Texas to the Gulf of …

Design And Development Of Transition Metal-Based Electrocatalysts For Environmentally Friendly And Efficient Hydrogen Evolution Reactions (Her), Navid Attarzadeh

Open Access Theses & Dissertations

Hydrogen fuel is a clean energy source primarily because it emits no carbon dioxide (CO2). Sustainable energy alternatives have attracted the scientific community and policymakers as concerns over global warming and depletion of fossil fuels have increased significantly. Substituting H2 gas as a primary source for our daily energy consumption under the guideline of the hydrogen economy concept has not progressed as anticipated because of inadequate efficiency associated with the generation (electrolyzer) and utilization (fuel cell) devices. However, there are challenges associated with hydrogen that must be overcome for it to become a truly sustainable and widespread energy source. The …

Removal Of Nonylphenols From Water And Wastewater Using Alginate-Activated Carbon Beads, Angelica Araly Chacon

Open Access Theses & Dissertations

The presence of contaminants of emerging concern (CECs) have been affecting water quality in recent years. The United States Environmental Protection Agency (U.S EPA) defines CECs as toxic chemicals without regulatory status and with adversely impact on the wildlife and people. Among the CECs, nonylphenols (NPs) are frequently found in all water systems and are categorized as endocrine-disrupting compounds (EDCs) due to their ability to mimic hormones causing reproductive and developmental effects in humans and animals. The main sources of discharge and distribution of NPs into the environment are wastewater treatment plants (WWTPs) which are not designed to remove them. …

Interdisciplinary Approach To Understanding Stakeholder Reasoning And Decision-Making For Water, Katalina Salas

Open Access Theses & Dissertations

On a global scale, humanity is compelled to address complex or â??wickedâ?? resource-related issues in the face of accelerating environmental change. In our work, we use the term wicked problem to refer to an issue that has multiple potential solutions and involves various stakeholders. The paths to reach resource sustainability under environmental uncertainty are difficult to identify, plausible outcomes remain uncertain, and tradeoffs required by any path chosen are challenging to understand. Environmental sustainability issues may involve perspectives from multiple stakeholders (i.e., scientists, policymakers, community members, and industry), often leading to conflicting interests and cultural misalignments that trigger the need …

Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin

Open Access Theses & Dissertations

A pilot scale coupled photovoltaic-thermal solar powered desalination system was evaluated at the Brackish Groundwater National Desalination Research Facility (BGNDRF). The pilot system consisted of a 3-kW photovoltaic-thermal (PVT) solar panel array and a 2.3 kW photovoltaic (PV) array coupled with a 4 gal/min single-stage 4 membrane reverse osmosis (RO) desalination system. A heat exchange system was in place to provide simultaneous cooling for the PVT system and heating to the RO system feed water. This system was evaluated with three objectives in mind. The first objective was to identify whether cooling of the PVT panels resulted in a significant …

How Active Rainwater Harvesting May Help Reduce Nuisance Flooding: Flood Analysis And Social Barriers To Adoption, Isabel Lopez

Open Access Theses & Dissertations

As urbanization continues to expand, fewer pervious surfaces are available to help reduce stormwater runoff from rainfall. The impacts of urbanization are becoming evident through sunny day flooding - flooding that occurs in areas not designated by the Federal Emergency Management Agency (FEMA) as flood zones. Nevertheless, water accumulates in low-lying areas and compromises street intersections and other parts of neighborhoods. Some methods can help alleviate the impacts of unexpected heavy rains, such as passive and active rainwater harvesting. As a pilot study, in a selected area in the northeast of El Paso, the level of adoption (e.g., what percentage …

Temporal Trends In Dryland Soil Carbon Fluxes In Response To Artificial And Natural Pulsed Moisture Events, Briana Alyce Salcido

Open Access Theses & Dissertations

Critical zone processes in drylands play a crucial role in the global carbon cycle, and one of the most important processes is soil CO2 efflux at the interface between soils and the atmosphere, which represents a main pathway for loss of carbon. Predicting the carbon dynamics at this interface is challenging due to the complexity of belowground processes, which include both biotic (soil respiration) and abiotic (calcite precipitation) production of CO2, as well as transport processes that include both diffusive and advective components. In this study, we aimed to investigate the contribution of soil air displacement to soil CO2 efflux …

Multi-Objective Optimization Framework For Electrified Vehicle Penetration Based On Life Cycle Assessment And Life Cycle Cost., Eva Alondra Diaz Lozano

Open Access Theses & Dissertations

This research proposed a novel framework for creating optimal transportation scenarios that consider multiple objectives such as minimum greenhouse gas emissions, air pollutant levels, and cost of ownership. The thesis approach is a multi-objective evolutionary algorithm coupled with the AFEET tool, allowing us to efficiently explore the complex trade-offs between these objectives and identify a diverse set of optimal solutions. Through several case studies and a design of experiments, this demonstrates the effectiveness and practicality in different scenarios. This approach has significant implications for policymakers and industry professionals seeking to make sustainable and cost-effective decisions in the transportation sector.

Characterizing Spatial Variability In Soil Co2 Fluxes In The Chihuahuan Desert Using Geostatistical Techniques, Viridiana Orona

Open Access Theses & Dissertations

Spatial variability in soil CO2 efflux across landscapes is an important feature of the â??Critical Zoneâ?? within dryland ecosystems. In dryland critical zones, resources are often distributed in patches or resource islands. Although this is particularly true in natural settings, the significance of spatial variability in CO2 efflux and its patterns also extends to dryland agriculture. In both irrigated and unirrigated systems, human management practices can significantly impact both organic and inorganic carbon cycling processes, highlighting the importance of studying CO2 efflux in these systems. We examined the spatial patterns of soil CO2 efflux and quantified the magnitude and scale …

Addressing The Challenged Of Dcop Based Decision-Making Algorithms In Modern Power Systems, Luis Daniel Ramirez Burgueno

Open Access Theses & Dissertations

Natural disasters have been determined as the leading cause of power outages, causing not only huge economic losses, but also the interruption of crucial welfare activities and the arise of security concerns. Because of the later, decision-making considering grid modernization, power system economics, and system resiliency has been a crucial theme in power systemsâ?? research. The need to better withstand catastrophic events and reducing the dependency of bulky generating units has propelled the development and better management of behind-the-meter generation or distributed energy resources (DERs). DERs can assist in the grid in different manners, not only by meeting energy demand …

The Intersection Of Urban Heat Islands And The Cdc Social Vulnerability Index In Two Border Cities, Ileana Morales

Open Access Theses & Dissertations

No abstract provided.

Sulfonated Styrene Grafted Sebs/Abs Made By Additive Manufacturing For Ion Exchange Applications, Avianna Elaine Gallegos

Open Access Theses & Dissertations

An interpenetrating polymer network (IPN) for cation exchange applications was synthesized from a blend of styrene-ethylene/butylene-styrene (SEBS) and acrylonitrile butadiene styrene (ABS), which was 3D printed, grafted with crosslinked polystyrene (PS), and sulfonated. A method for styrene grafting was applied to reduce the damage to polymer phases caused by the sulfonation reaction. Styrene and divinylbenzene monomers were introduced to the IPN and induced with heat treatment to polymerize in situ. The graft copolymerization reaction was enhanced with varying quantities of benzoyl peroxide as a chemical initiator. The samples were subsequently sulfonated with chlorosulfonic acid in dichloroethane and functionalized for ion …

Glacier Segmentation From Remote Sensing Imagery Using Deep Learning, Bibek Aryal

Open Access Theses & Dissertations

Large-scale study of glaciers improves our understanding of global glacier change and is imperative for monitoring the ecological environment, preventing disasters, and studying the effects of global climate change. In recent years, remote sensing imagery has been preferred over riskier and resource-intensive field visits for tracking landscape level changes like glaciers. However, periodic manual labeling of glaciers over a large area is not feasible due to the considerable amount of time it requires while automatic segmentation of glaciers has its own set of challenges. Our work aims to study the challenges associated with segmentation of glaciers from remote sensing imagery …

Black And Brown Carbon Optical Characterization In The El Paso - Ciudad Juarez Airshed, Pamela I. Lara

Open Access Theses & Dissertations

Black (EBC) and Brown (BrC) Carbon are ubiquitous constituents of atmospheric particulate matter that affect peopleâ??s health, disrupt ecosystems, and modulate local and global climate. Tracking the local deposition and sources of these aerosol particles is essential to better understanding their multidimensional environmental impact. The main goal of the current study is to measure the absorption coefficient (Babs) of particles within the Planetary Boundary Layer (PBL) of the El Paso (US)–Ciudad Juárez (Mexico) airshed and assess the contribution of black and brown carbon particles to the total optical absorption. Measurements were taken during winter (January, 2022), spring (May, 2022), and …

The Qualification Of Sealability And Creep Relaxation Of Additively Manufactured Zytel Gaskets For Pem Fuel Cells, Robert Lazarin

Open Access Theses & Dissertations

The purpose of this thesis is to study the feasibility of low-cost additive manufacturing of gaskets for proton exchange membrane fuel cells exposed to extreme temperature conditions ranging from -55°C to 100°C. With the growing popularity and decreasing costs of additive manufacturing technologies, specifically Material Extrusion (ME), research is being conducted to determine the feasibility of ME components. Thermally cycled PEMFCs may exhibit accelerated gasket deterioration, therefore, the mechanical stability of material extruded gaskets following a harsh thermal cycle must be assessed. The feasibility of the material extruded gaskets will be proven by manufacturing optimization and mechanical testing. The target …

A Case Study In Design, Construction, And Operation Of A Meromictic Solar Pond In Texas, Usa, Bianca Paola Meneses Brassea

Open Access Theses & Dissertations

Over the last four decades, meromictic solar ponds have been the subject of limnological studies and engineering research. A case of practical interest is the salinity gradient solar pond (SGSP). SGSP science and technologies have been systemically advanced in El Paso, Texas. This dissertation aims to share lessons learned in designing, constructing, and operating the El Paso Solar Pond, a NaCl-based solar pond that achieved high-temperature performance over two decades, commencing in 1984. Many of the practical lessons learned have not been published and are thus not readily available in archival journals, and this contribution provides a remedy. The value …