Digital Commons Network^™

Thermal Convection In A Cylindrical Annulus Filled With Porous Material, Anirban Ray

Theses and Dissertations

Here a study on thermal convection in a porous vertical cylindrical annulus which is heated from below is carried out. The walls are considered to be impermeable that is the velocity is 0 at the boundary walls. The cylindrical annulus is radially insulated. The governing system consists of the continuity equation, Darcy-Boussinesq equation, heat equation and the equation of state. Employing weakly non-linear approach, the basic state system and the perturbed system are derived. After obtaining the solutions to the basic state system, the pressure term in perturbed system is eliminated by taking double curl, and then eliminating the velocity, …

Assessing Intra-Urban Particulate Matter (Pm2.5) Concentrations At The Lower Rio Grande Valley (Rgv), South Texas, Usa, Using Low-Cost Sensors, Esmeralda Mendez

Theses and Dissertations

Rapid technological developments of novel low-cost air quality sensors enable long-term ambient monitoring in neighborhood areas. In this study, spatial and temporal trends are analyzed by localized level monitoring with low-cost sensors (TSI BlueSky Air Quality Monitor). Eleven low-cost sensors were deployed across the Lower Rio Grande Valley, South Texas region: Brownsville, Edinburg, Weslaco, and Port Isabel. 24-hour PM2.5 concentrations are correlated with PM2.5 from existing Texas Commission on Environmental Quality (TCEQ) Continuous Ambient Monitoring Stations (CAMSs) to express temporal and spatial heterogeneity from March 01, 2021, to March 31, 2022. Results indicated the deployed low-cost sensors as a better …

Could Cultures Determine The Course Of Epidemics And Explain Waves Of Covid-19?, Md Salman Rahman

Theses and Dissertations

Coronavirus Disease (COVID-19), caused by the SARS-CoV-2 virus, is an infectious disease that quickly became a pandemic spreading with different patterns in each country. Travel bans, lockdowns, social distancing, and non-essential business closures caused significant economic disruptions and stalled growth worldwide in the pandemic’s first year. In almost every country, public health officials forced and/or encouraged Nonpharmaceutical Interventions (NPIs) such as contact tracing, social distancing, masks, and quarantine. Human behavioral decision-making regarding social isolation significantly impedes global success in containing the pandemic. This thesis focuses on human behaviors and cultures related to the decision-making of social isolation during the pandemic. …

Growth And Reproduction In Gulf Of Mexico Black Corals (Antipatharians) In Field And Laboratory Studies, Victoria E. Salinas

Theses and Dissertations

Black corals provide an important ecosystem of marine life and are found throughout all the oceans of the world at depths between 2 and 8,600 m. However, little is understood about their life history and the factors that control the distribution of black corals, particularly in the Gulf of Mexico (GoM). Given the impacts of the Deepwater Horizon oil spill on soft corals (e.g., black corals and octocorals) in the GoM, studies of their growth and reproductive biology in both natural and aquaculture environments are crucial for restoration efforts. The objectives of this study were to examine reproductive processes, compare …

Network Analysis Of Scientific Research In The Gulf Of Mexico, Juliet S. Vallejo

Theses and Dissertations

The Gulf of Mexico ecosystem represents a significant management challenge in its 3,423-mile coastline and transnational regulatory setting, along five states from the United States, six states from Mexico, and Cuba which borders the southeastern quadrant. Providing various resources to the regional economies, the continued success of these resources depends on the collaboration among transnational participants in bringing together complementary skills and multidisciplinary approaches to producing, circulating, and utilizing scientific knowledge. Using bibliometric analysis of Gulf of Mexico-related published research over 18 years from 2000 to 2018 allows for identifying organizations, their connections, and trends in the production of scientific …

Neural Networks And Stochastic Differential Equations, Stephanie L. Flores

Theses and Dissertations

Influenced by the seminal work, “Physics Informed Neural Networks” by Raissi et al., 2017, there has been a growing interest in solving and parameter estimation of Nonlinear Partial Differential Equations (PDE) with Deep Neural networks in recent years. In fact, this has broadened the pathways and shed light on deep learning of stochastic differential equations (SDE) and stochastic PDE’s (SPDE).In this work, we intend to investigate the current approaches of solving and parameter estimation of the SDE/SPDE with deep neural networks and the possibility of extending them to obtain more accurate/stable solutions with residual systems and/or generative adversarial neural networks. …

Financial Literacy And Consumer Well-Being: Examining The Role Of Gender Role Ideology, Lorena Garcia Ramon

Theses and Dissertations

Financial literacy, or the ability to process economic information and make informed decisions about financial planning, wealth accumulation, debt, and pensions, has been linked to beneficial financial behaviors that support financial well-being. Despite these benefits, consumers tend to underperform in financial literacy tests with women generally faring worse than men. This dissertation draws from gender roles literature and Expectancy-Value Theory to examine how, why, and when traditional attitudes regarding societal gender roles (i.e., gender role ideology) hinder women’s financial literacy and willingness to acquire financial knowledge. Moreover, it examines how financial literacy and willingness to …

A Gpu Accelerated Genetic Algorithm For The Construction Of Hadamard Matrices, Andras Balogh, Raven Ruiz

School of Mathematical & Statistical Sciences Faculty Publications

We use a genetic algorithm to construct Hadamard Matrices. The initial population of random matrices is generated to have a balanced number of +1 and −1 entries in each column except the first column with all +1. Several fitness functions are implemented in order to find the most effective one. The crossover process creates offspring matrix population by exchanging columns of the parent matrix population. The mutation process flips +1 and −1 entry pairs in random columns. The use of CuPylibrary in Python on graphics processing units enables us to handle populations of thousands of matrices and matrix operations in …

Defining The Current Distribution Of The Imperiled Black-Spotted Newt Across South Texas, Usa, Padraic S. Robinson, Drew R. Davis, Sean M. Collins, Richard Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Black-spotted Newt (Notophthalmus meridionalis) is a chronically understudied salamander species, with many aspects of its natural history, ecology, and distribution poorly known. Previous studies using traditional methodologies have had limited success documenting N. meridionalis on the landscape, detecting individuals at 6% (7 of 114) and 1% (2 of 221) of sites surveyed. A novel environmental DNA (eDNA) assay was designed and implemented with the goals of assessing the current distribution of N. meridionalis across south Texas, USA, and better understanding the conditions for positive eDNA detections. We conducted eDNA sampling and traditional surveys at 80 sites throughout …

A Comprehensive Review On The Diverse Pharmacological Perspectives Of Terminalia Chebula Retz, Md. Rakibul Hassan Bulbul, Mohammad Nizam Uddin Chowdhury, Taslima Anjum Naima, Md. Shakil Imtiaj, Nazmul Huda, Md. Giash Uddin

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

Terminalia chebula Retz, commonly known as ‘Haritaki/Myrobalan,’ has been utilised as a traditional medicine for a long time. It has been extensively exercised in various indigenous medicine practices like Unani, Tibb, Ayurveda, and Siddha to remedy human ailments such as bleeding, carminative, dysentery, liver tonic, digestive, antidiarrheal, analgesic, anthelmintic, antibacterial and helpful in skin disorders. Studies on the pharmacological effects of T. chebula and its phytoconstituents documented between January, 1996 and December, 2021 were explored using various electronic databases. During the time mentioned above, several laboratory approaches revealed the biological properties of T. chebula, including antioxidative, antiproliferative, anti-microbial, proapoptotic, …

Fish Community Analysis Using Multidirectional Rov Video Surveys In The Northwestern Gulf Of Mexico, Keegan J. Angerer

Theses and Dissertations

In this study, ROV surveys with multidirectional video were used to analyze the fish communities associated with artificial reef patches in the Rio Grande Valley artificial reef 13.7 km off the coast of South Padre Island, TX. Nine configurations of reef patches consisting of varying combinations and densities of concrete pyramid and low-profile modules were surveyed. The highest species diversity was found at patches with large deployments of both pyramids and low-profile modules. Total Red Snapper Lutjanus campechanus abundance did not differ between configurations, but the highest abundances of juvenile Red Snapper were found at configurations with one pyramid and …

Assessment Of Nitrogen-Based Fertilizer Transport And Microbial Activities In Sandy Soil Profiles In South Texas, Gladys De La Rosa

Theses and Dissertations

Conventional farming is a common practice in Lower Rio Grande Valley (LRGV) and the application of nitrogen fertilizer is essential for plant growth and support. However, managing the rate of nitrogen that is applied can benefit farmers financially and reduce nitrate leaching that can have an adverse effect on the local environment and aquatic systems, e.g., rivers and estuaries. Sandy soils are more vulnerable to water infiltration due to the large proportion of macropores. This study aims to (i) assess how nitrate from a variety of fertilizers (i.e., synthetic and organic) distributes on the top 60 cm layer of a …

Red Drum (Sciaenops Ocellatus) Trophic Web Reconstruction Using Stable Isotopes In Two Systems In The Northwestern Gulf Of Mexico, Elizabeth Mogus Garcia

Theses and Dissertations

Estuaries act as nurseries for many important fishes, including predators like Red Drum (Sciaenops ocellatus). Using gut content and stable isotope analyses to better understand juvenile S. ocellatus’ diet and role within the trophic web, a full year of data was collected on a quarterly basis to illustrate a change in diet based on resource availability at two study sites and for two non-overlapping S. ocellatus sizes. Panopeidae and Penaeidae were the most abundant prey items found in S. ocellatus stomachs for both sizes, sites, and four quarters representing over 50% of the diet. Stable isotope analyses …

Getting By (Or Not) With A Little Help From My Friends: Intersections Of Financial Literacy, Race And Gender On Source Of Financial Information, Catherine Wacera Muriuki

Theses and Dissertations

Financial literacy is important to individuals as well as to the economy. It is touted as crucial for individuals because it allows them to make informed decisions on credit and saving products. To the economy, it is the bedrock upon which micro-and macro-policies are embedded. Financial literacy is said to be a springboard to financial capability, enhancing a person’s ability to manage their monies, make informed investment decisions, and take control of their financial advancement. Low financial literacy is often associated with larger unbanked or underbanked populations. According to 2019 NFEC data, after administering a financial literacy test, only 66% …

Traveling Wave Solutions For The Negative Order Hierarchy Of The D-Akns Equations, Brayton Isaac Wario

Theses and Dissertations

In the thesis work, based on the D-AKNS spectral problem, we study the negative-order D-AKNS (ND-AKNS) hierarchy. In particular, the first ND-AKNS equation is derived from the negative-order D-AKNS hierarchy, which is proved integrable in the sense of Lax pair. Furthermore, we discuss the traveling wave solutions to the ND-AKNS Equation, including possible soliton solutions.

Latina Preservice Teachers Embodying Teacher Identity Through Improvisation, Zulema Williams

Theses and Dissertations

Latina preservice science teachers make the transition from science student to teacher is scant. This study aims to address this gap by exploring improvisation as a pedagogical tool in order for Latina pre-service teachers make meaning of the transition from student to teacher and what this might mean in terms of identity.

According to Pool et al. (2011), “[u]sing arts-based instruction in a preservice teacher program has promise for fostering better pedagogical decisions to benefit learners at every level.” (p. 9). The purpose of this case-study is not only to fill a gap in the literature but also to explore …

Quantization For A Probability Distribution Generated By An Infinite Iterated Function System, Lakshmi Roychowdhury, Mrinal Kanti Roychowdhury

School of Mathematical & Statistical Sciences Faculty Publications

Quantization for probability distributions concerns the best approximation of a d-dimensional probability distribution P by a discrete probability with a given number n of supporting points. In this paper, we have considered a probability measure generated by an infinite iterated function system associated with a probability vector on ℝ. For such a probability measure P, an induction formula to determine the optimal sets of n-means and the nth quantization error for every natural number n is given. In addition, using the induction formula we give some results and observations about the optimal sets of n-means for all n ≥ 2.

Whole Genome Sequence Association Analysis Of Fasting Glucose And Fasting Insulin Levels In Diverse Cohorts From The Nhlbi Topmed Program, Daniel Dicorpo, Sheila M. Gaynor, Emily M. Russell, Kenneth E. Westerman, Laura M. Raffield, Marcio Almeida, Juan M. Peralta, John Blangero, Joanne E. Curran, Ravindranath Duggirala

School of Medicine Publications

The genetic determinants of fasting glucose (FG) and fasting insulin (FI) have been studied mostly through genome arrays, resulting in over 100 associated variants. We extended this work with high-coverage whole genome sequencing analyses from fifteen cohorts in NHLBI’s Trans-Omics for Precision Medicine (TOPMed) program. Over 23,000 non-diabetic individuals from five race-ethnicities/populations (African, Asian, European, Hispanic and Samoan) were included. Eight variants were significantly associated with FG or FI across previously identified regions MTNR1B, G6PC2, GCK, GCKR and FOXA2. We additionally characterize suggestive associations with FG or FI near previously identified SLC30A8, TCF7L2, and ADCY5 regions as well …

Phase Transitions And Resilience Of The Magnetic Dual Chiral Density Wave Phase At Finite Temperature And Density, William Gyory, Vivian De La Incera

Physics & Astronomy Faculty Publications

We study the phase transitions at finite temperature and density of the magnetic dual chiral density wave (MDCDW) phase. This spatially inhomogeneous phase emerges in cold, dense QCD in the presence of a strong magnetic field. Starting from the generalized Ginzburg-Landau (GL) expansion of the free energy, we derive several analytical formulas that enable fast numerical computation of the expansion coefficients to arbitrary order, allowing high levels of precision in the determination of the physical dynamical parameters, as well as in the transition curves in the temperature vs chemical potential plane at different magnetic fields. At magnetic fields and temperatures …

Analysis Of Urbanization And Climate Change Effects On Community Resilience In The Rio Grande Valley, South Texas, George Atisa, Alexis Racelis

School of Earth, Environmental, & Marine Sciences Faculty Publications

Disruptive development events have tested and will continue to test community resilience as people work to balance healthy living, economic growth, and environmental quality. Aspects of urbanization, if not designed and guided by healthy living strategies, convert natural areas into built environments, thus reducing the diversity of plant and animal species that are the foundation of resilience in communities. In this study, we attempted to answer the following question: What are the most effective ways to ensure that ongoing urbanization and climate change do not negatively affect ecological services and community resilience in the Rio Grande Valley (RGV)? The region …

Hybrid Conferences: Opportunities, Challenges And Ways Forward, Eleonora Puccinelli, Daniela Zeppilli, Paris V. Stefanoudis, Annaig Wittische-Helou, Marjorie Kermorgant, Sandra Fuchs, Lenaick Menot, Erin E. Easton, Alexandra A-T. Weber

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hybrid conferences are in-person events that have an online component. This type of meeting format was rare before the COVID-19 pandemic, but started to become more common recently given the asynchronous global progression of the pandemic, the uneven access to vaccines and different travel regulations among countries that led to a large proportion of participants being unable to attend conferences in person. Here we report the organization of a middle-sized (581 participants: 159 onsite, 422 online) international hybrid conference that took place in France in September 2021. We highlight particular organizational challenges inherent to this relatively new type of meeting …

Iron And Magnesium Impregnation Of Avocado Seed Biochar For Aqueous Phosphate Removal, James Jihoon Kang, Jason Parsons, Sampath Gunukula, Dat T. Tran

School of Earth, Environmental, & Marine Sciences Faculty Publications

There has been increasing interest in using biochar for nutrient removal from water, and its application for anionic nutrient removal such as in phosphate (PO₄³⁻) necessitates surface modifications of raw biochar. This study produced avocado seed biochar (AB), impregnated Fe- or Mg-(hydr)oxide onto biochar (post-pyrolysis), and tested their performance for aqueous phosphate removal. The Fe- or Mg-loaded biochar was prepared in either high (1:8 of biochar to metal salt in terms of mass ratio) or low (1:2) loading rates via the co-precipitation method. A total of 5 biochar materials (unmodified AB, AB + High Fe, AB …

Effect Of Ultraviolet Light Treatment On Microbiological Safety And Quality Of Fresh Produce: An Overview, Veerachandra K. Yemmireddy, Achyut Adhikari, Juan Moreira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Fresh and fresh-cut fruits and vegetables have been associated in several foodborne illness outbreaks. Although investigations from those outbreaks reported that the contamination with pathogenic microorganisms may occur at any point in the farm to fork continuum, effective control strategies are still being widely investigated. In that direction, the concept of hurdle technology involving a sequence of different interventions have been widely explored. Among those interventions, ultraviolet (UV) light alone or in combination with other treatments such as use of organic acids or sanitizer solutions, has found to be a promising approach to maintain the microbiological safety and quality of …

Failure Detection In Deep Neural Networks For Medical Imaging, Sabeen Ahmed, Dimah Dera, Saud Ul Hassan, Nidhal Bouaynaya, Ghulam Rasool

Electrical and Computer Engineering Faculty Publications

Deep neural networks (DNNs) have started to find their role in the modern healthcare system. DNNs are being developed for diagnosis, prognosis, treatment planning, and outcome prediction for various diseases. With the increasing number of applications of DNNs in modern healthcare, their trustworthiness and reliability are becoming increasingly important. An essential aspect of trustworthiness is detecting the performance degradation and failure of deployed DNNs in medical settings. The softmax output values produced by DNNs are not a calibrated measure of model confidence. Softmax probability numbers are generally higher than the actual model confidence. The model confidence-accuracy gap further increases for …

The Cartesian Analytical Solutions For The N-Dimensional Compressible Navier-Stokes Equations With Density-Dependent Viscosity, Engui Fan, Zhijun Qiao, Manwai Yuen

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, we prove the existence of general Cartesian vector solutions u=b(t)+A(t)x for the N-dimensional compressible Navier-Stokes equations with density-dependent viscosity, based on the matrix and curve integration theory. Two exact solutions are obtained by solving the reduced systems.

Investigation On The Synthesis, Application And Structural Features Of Heteroaryl 1,2-Diketones, Robert J. Wehrle, Alexander Rosen, Thu Vu Nguyen, Kalyn Koons, Eric Jump, Mason Bullard, Natalie Wehrle, Adam Stockfish, Patrick M. Hare, Abdurrahman Atesin, Tülay A. Ateşin, Lili Ma

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

A set of unsymmetrical heteroaryl 1,2-diketones were synthesized by a heteroarylation/oxidation sequence with up to 65% isolated yields. Palladium catalyst XPhos Pd G4 and SeO2 were the key reagents used in this methodology, and microwave irradiation was utilized to facilitate an efficient and ecofriendly process. The application of heteroaryl 1,2-diketones is demonstrated through the synthesis of an unsymmetrical 2-phenyl-3-(pyridin-3-yl)quinoxaline (5a) from 1-phenyl-2-(pyridin-3-yl)ethane-1,2-dione (4a). The lowest energy conformations of 4a and 5a were located using Density Functional Theory (DFT) at the M06-2X/def2-TZVP level of theory. Two lowest energy conformations of 4a differ with respect to the position of the N atom …

Reducing Leakage Current And Enhancing Polarization In Multiferroic 3d Super-Nanocomposites By Microstructure Engineering, Erik Enriquez, Ping Lu, Leigang Li, Bruce Zhang, Haiyan Wang, Quanxi Jia, Aiping Chen

Physics & Astronomy Faculty Publications

Multiferroic materials have generated great interest due to their potential as functional device materials. Nanocomposites have been increasingly used to design and generate new functionalities by pairing dissimilar ferroic materials, though the combination often introduces new complexity and challenges unforeseeable in single-phase counterparts. The recently developed approaches to fabricate 3D super-nanocomposites (3D‐sNC) open new avenues to control and enhance functional properties. In this work, we develop a new 3D‐sNC with CoFe2O4 (CFO) short nanopillar arrays embedded in BaTiO3 (BTO) film matrix via microstructure engineering by alternatively depositing BTO:CFO vertically-aligned nanocomposite layers and single-phase BTO layers. This microstructure engineering method allows …

Disaster Resilience Versus Ecological Resilience And The Proposed Second Causeway To South Padre Island, Juliet Vallejo, Katia Sanchez, Evelyn Roozee, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

The barrier island of South Padre is located off the coast of Texas’s southern tip in Cameron County and is a popular tourist destination with over 4 million annual visits. The only road access to and from the island is a four-lane causeway, 2.3 miles in length, that routinely experiences heavy traffic. Twenty years ago, a barge crashed into the Queen Isabella Causeway, destroying a portion of the bridge. It quickly became apparent how reliant South Padre Island (SPI) is on the causeway and raised questions regarding its lack of disaster resilience. Local boosters and government responded by proposing and …

Reducing Leakage Current And Enhancing Polarization In Multiferroic 3d Supernanocomposites By Microstructure Engineering, Erik Enriquez, Ping Lu, Leigang Li, Bruce Zhang, Haiyan Wang, Quanxi Jia, Aiping Chen

Computer Science Faculty Publications

Multiferroic materials have generated great interest due to their potential as functional device materials. Nanocomposites have been increasingly used to design and generate new functionalities by pairing dissimilar ferroic materials, though the combination often introduces new complexity and challenges unforeseeable in single-phase counterparts. The recently developed approaches to fabricate 3D super-nanocomposites (3D‐sNC) open new avenues to control and enhance functional properties. In this work, we develop a new 3D‐sNC with CoFe2O4 (CFO) short nanopillar arrays embedded in BaTiO3 (BTO) film matrix via microstructure engineering by alternatively depositing BTO:CFO vertically-aligned nanocomposite layers and single-phase BTO layers. This microstructure engineering method allows …

Dynamic Robot Chain Networks For Swarm Foraging, Dohee Lee, Qi Lu, Tsz-Chiu Au

Computer Science Faculty Publications

The objective of foraging robot swarms is to search for and collect resources in an unknown arena as quickly as possible. To avoid the congestion near the central collection zone, we previously proposed an extension to the multiple-place foraging in which robot chains are deployed dynamically so that foraging robots can deliver to the robot chains instead of the central collection zone. However, a robot chain can only reach one location at a time, and congestion can occur at the end of the robot chain. This paper presents an extension to dynamic robot chains called dynamic robot chain networks, which …