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Production Of Distilled Spirits Using Grain Sorghum Through Liquid Fermentation, Thomas Weiss, Jikai Zhao, Ruijia Hu, Meicen Liu, Yonghui Li, Yi Zheng, Gordon Smith, Donghai Wang Sep 2022

Production Of Distilled Spirits Using Grain Sorghum Through Liquid Fermentation, Thomas Weiss, Jikai Zhao, Ruijia Hu, Meicen Liu, Yonghui Li, Yi Zheng, Gordon Smith, Donghai Wang

School of Earth, Environmental, & Marine Sciences Faculty Publications

The objectives of this research were to investigate the fermentation performance of US sorghum varieties for the production of distilled spirits as well as their associated coproducts and to study the formation of volatile compounds that are related to the flavor quality of the spirits. Three US sorghum varieties (red, white, and waxy sorghums) and four yeast strains (DADY, Ethanol Red, GR-2, and 71B) were used for distilled spirit production. Both sorghum variety and type of yeast strains had effects on alcohol concentration and alcohol yield. The alcohol concentration varied from 10.26 to 11.34% (v/v) while alcohol yield varied from …


Fine Particulate Matter Concentrations During Independence Day Fireworks Display In The Lower Rio Grande Valley Region, South Texas, Usa, Esmeralda Mendez, Owen Temby, Dawid K. Wladyka, Katarzyna Sepielak, Amit U. Raysoni Sep 2022

Fine Particulate Matter Concentrations During Independence Day Fireworks Display In The Lower Rio Grande Valley Region, South Texas, Usa, Esmeralda Mendez, Owen Temby, Dawid K. Wladyka, Katarzyna Sepielak, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Fireworks are typically discharged as a mark of celebration and joy in many societies spanning various cultures. In the United States of America, 4th July is celebrated as the Independence Day when the nation overthrew the British colonial yoke in 1776. While this day instills a sense of patriotism in every American’s heart, it is also a major PM2.5 air pollution concern. This study is first of its type in the Lower Rio Grande Valley (RGV) Region of South Texas, USA, that characterizes fine particulate matter pollution. Using a low-cost sensor (TSI BlueSky Air Quality Monitor), real-time PM2.5 measurements were …


Definite Condition Of The Evolutionary (P)Over-Right-Arrow(X)-Laplacian Equation, Huashui Zhan, Zhaosheng Feng Sep 2022

Definite Condition Of The Evolutionary (P)Over-Right-Arrow(X)-Laplacian Equation, Huashui Zhan, Zhaosheng Feng

School of Mathematical & Statistical Sciences Faculty Publications

For the nonlinear degenerate parabolic equations, how to find an appropriate boundary value condition to ensure the well-posedness of weak solution has been an interesting and challenging problem. In this paper, we develop the general characteristic function method to study the stability of weak solutions based on a partial boundary value condition.


Why New Zealand’S Indigenous Reconciliation Process Has Failed To Empower Māori Fishers: Distributional, Procedural, And Recognition-Based Injustices, Hekia Bodwitch, Andrew M. Song, Owen Temby, John Reid, Megan Bailey, Gordon M. Hickey Sep 2022

Why New Zealand’S Indigenous Reconciliation Process Has Failed To Empower Māori Fishers: Distributional, Procedural, And Recognition-Based Injustices, Hekia Bodwitch, Andrew M. Song, Owen Temby, John Reid, Megan Bailey, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

How is it that the New Zealand government’s process for re-establishing Indigenous fishing rights has failed to deliver thriving Māori fisheries? This paper examines why, at Te Waihora, a coastal lake, and site of one of the nation’s longest running and best-funded state-Māori co-governance agreements, Māori fishers have been unable to use their rights to support their fishery. As of 2018, the lake’s culturally and ecologically significant eel population was no longer commercially viable, a decline fishers have attributed to rampant dairy industry expansion upstream. Drawing on environmental justice literatures, we deploy a multi-dimensional framework to identify factors shaping possibilities …


Chainscan: A Blockchain-Based Supply Chain Alerting Framework For Food Safety, Jorge Castillo, Kevin Barba, Qian Chen Sep 2022

Chainscan: A Blockchain-Based Supply Chain Alerting Framework For Food Safety, Jorge Castillo, Kevin Barba, Qian Chen

Informatics and Engineering Systems Faculty Publications

Supply Chain Management (SCM) systems provide a digital platform for the supply chain organizations to communicate and exchange information. In the food industry, SCMs provide the essential software components for monitoring food transportation and product handling. However, contemporary SCM systems suffer from non-traceability, non-interoperability and poor resiliency. Global food supply chains are at risks from cyber threats, which will lead to food shortages and poor quality control. In this paper, we present ChainSCAN, a three-layer design of a fully decentralized and blockchain-based SCM system that protects data security, privacy, and remove single point of failures of traditional SCMs. In addition, …


Low Soil Nitrogen And Moisture Limit The Expansion Of The Invasive Grass, Megathyrsus Maximus (Guinea Grass) In Semi-Arid Soils, E. Penelope Holland, Vanessa Thomas, Pushpa G. Soti Sep 2022

Low Soil Nitrogen And Moisture Limit The Expansion Of The Invasive Grass, Megathyrsus Maximus (Guinea Grass) In Semi-Arid Soils, E. Penelope Holland, Vanessa Thomas, Pushpa G. Soti

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

The goal of this study was to predict the range expansion potential of an invasive forage grass, Guinea grass (Megathyrsus maximus). We collected rhizosphere soil samples of M. maximus and coexisting species from 150 different locations and analysed them for soil properties. We estimated the probability of M. maximus presence as a function of soil moisture, organic matter, pH, salinity, total N, and CN ratio using logistic regression. Presence of M. maximus was associated with higher soil moisture, higher organic matter, pH, and nitrogen, but lower salinity and CN ratio. Soil nitrogen and moisture …


Excitation-Dependent Photoluminescence Of Bazro3:Eu3+ Crystals, Santosh K. Gupta, Hisham Abdou, Carlo U. Segre, Yuanbing Mao Aug 2022

Excitation-Dependent Photoluminescence Of Bazro3:Eu3+ Crystals, Santosh K. Gupta, Hisham Abdou, Carlo U. Segre, Yuanbing Mao

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

The elucidation of local structure, excitation-dependent spectroscopy, and defect engineering in lanthanide ion-doped phosphors was a focal point of research. In this work, we have studied Eu3+-doped BaZrO3 (BZOE) submicron crystals that were synthesized by a molten salt method. The BZOE crystals show orange–red emission tunability under the host and dopant excitations at 279 nm and 395 nm, respectively, and the difference is determined in terms of the asymmetry ratio, Stark splitting, and intensity of the uncommon 5D0 → 7F0 transition. These distinct spectral features remain unaltered under different excitations for the BZOE …


Upcycling Mask Waste To Carbon Capture Sorbents: A Combined Experimental And Computational Study, Mark Robertson, Alejandro Guillen Obando, Bianca Nunez, Haoyuan Chen, Zhe Qiang Aug 2022

Upcycling Mask Waste To Carbon Capture Sorbents: A Combined Experimental And Computational Study, Mark Robertson, Alejandro Guillen Obando, Bianca Nunez, Haoyuan Chen, Zhe Qiang

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

Massive plastic pollution and grand scale emission of CO2 into the atmosphere represent two major and deeply connected societal challenges, which can have adverse impacts on climate, human health, and marine ecosystems. In particular, the COVID-19 pandemic led to substantially increased production, use, and discarding of disposable masks, a problem that requires urgent and effective technological solutions to mitigate their negative environmental impacts. Furthermore, over the years significant research efforts have sought to address the challenges of plastic waste and CO2 emission, such as development of chemical upcycling methods and low-cost CO2 capture sorbents at scale, respectively. In this work, …


In-Person Instruction Or Remote Learning?: Understanding Students' Learning Experiences During Covid-19, Eleazar Marquez, Samuel Garcia Aug 2022

In-Person Instruction Or Remote Learning?: Understanding Students' Learning Experiences During Covid-19, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

Research attests that student success in engineering education is cultivated largely due to classroom environments, academic inclusion, and engagement in undergraduate research. It is further revealed that the social and academic fabric of the institution such as academic advising, peer tutoring, disability services, and outdoor recreational programs is essential towards fostering well-being, recruitment, retention, and student success. However, these studies were conducted in a period in which students experienced traditional face-to-face instruction. In the wake of COVID-19, most institutions responded by terminating in-person instruction, mandating to seek off-campus housing, and shifting to a fully remote context. As such, educators were …


Detection Of Pancreatic Cancer Mirna With Biocompatible Nitrogen-Doped Graphene Quantum Dots, Ryan Ajgaonkar, Bong Lee, Alina Valimukhametova, Steven Nguyen, Roberto Gonzalez-Rodriguez, Jeffery Coffer, Giridhar R. Akkaraju, Anton V. Naumov Aug 2022

Detection Of Pancreatic Cancer Mirna With Biocompatible Nitrogen-Doped Graphene Quantum Dots, Ryan Ajgaonkar, Bong Lee, Alina Valimukhametova, Steven Nguyen, Roberto Gonzalez-Rodriguez, Jeffery Coffer, Giridhar R. Akkaraju, Anton V. Naumov

School of Medicine Publications

Early-stage pancreatic cancer remains challenging to detect, leading to a poor five-year patient survival rate. This obstacle necessitates the development of early detection approaches based on novel technologies and materials. In this work, the presence of a specific pancreatic cancer-derived miRNA (pre-miR-132) is detected using the fluorescence properties of biocompatible nitrogen-doped graphene quantum dots (NGQDs) synthesized using a bottom-up approach from a single glucosamine precursor. The sensor platform is comprised of slightly positively charged (1.14 ± 0.36 mV) NGQDs bound via π-π stacking and/or electrostatic interactions to the negatively charged (-22.4 ± 6.00 mV) bait ssDNA; together, they form a …


Engl 3360 - Introduction To Language Studies, Régine Pellicer Aug 2022

Engl 3360 - Introduction To Language Studies, Régine Pellicer

Open Educational Resources - Books

Language studies cover a large variety of situations as language is embedded in every aspect of our lives. Finding a book that would study all the possible topics related to language is impossible. Therefore, with our UTRGV librarians, we have assembled a free book that covers the basic linguistics concepts you need to know for this course and other linguistics courses. Linguistics concepts such as phonology or language acquisition are not subject to last minute discoveries and the principles remain the same. We hope you enjoy learning more about linguistics thanks to this free resource.


Statistical Analysis Methods Applied To Early Outpatient Covid-19 Treatment Case Series Data, Eleftherios Gkioulekas, Peter A. Mccullough, Vladimir Zelenko Aug 2022

Statistical Analysis Methods Applied To Early Outpatient Covid-19 Treatment Case Series Data, Eleftherios Gkioulekas, Peter A. Mccullough, Vladimir Zelenko

School of Mathematical & Statistical Sciences Faculty Publications

When confronted with a public health emergency, significant innovative treatment protocols can sometimes be discovered by medical doctors at the front lines based on repurposed medications. We propose a statistical framework for analyzing the case series of patients treated with such new protocols, that enables a comparison with our prior knowledge of expected outcomes, in the absence of treatment. The goal of the proposed methodology is not to provide a precise measurement of treatment efficacy, but to establish the existence of treatment efficacy, in order to facilitate the binary decision of whether the treatment protocol should be adopted on an …


Global Food Insecurity And Famine From Reduced Crop, Marine Fishery And Livestock Production Due To Climate Disruption From Nuclear War Soot Injection, Lilia Xia, Alan Robock, Kim J. N. Scherrer, Cheryl S. Harrison, Benjamin Leon Bodirsky, Isabelle Weindl, Jonas Jaegermeyr, Charles G. Bardeen, Owen B. Toon, Ryan F. Heneghan Aug 2022

Global Food Insecurity And Famine From Reduced Crop, Marine Fishery And Livestock Production Due To Climate Disruption From Nuclear War Soot Injection, Lilia Xia, Alan Robock, Kim J. N. Scherrer, Cheryl S. Harrison, Benjamin Leon Bodirsky, Isabelle Weindl, Jonas Jaegermeyr, Charles G. Bardeen, Owen B. Toon, Ryan F. Heneghan

School of Earth, Environmental, & Marine Sciences Faculty Publications

Atmospheric soot loadings from nuclear weapon detonation would cause disruptions to the Earth’s climate, limiting terrestrial and aquatic food production. Here, we use climate, crop and fishery models to estimate the impacts arising from six scenarios of stratospheric soot injection, predicting the total food calories available in each nation post-war after stored food is consumed. In quantifying impacts away from target areas, we demonstrate that soot injections larger than 5 Tg would lead to mass food shortages, and livestock and aquatic food production would be unable to compensate for reduced crop output, in almost all countries. Adaptation measures such as …


Towards Fast Weak Adversarial Training To Solve High Dimensional Parabolic Partial Differential Equations Using Xnode-Wan, Paul Valsecchi Oliva, Yue Wu, Cuiyu He, Hao Ni Aug 2022

Towards Fast Weak Adversarial Training To Solve High Dimensional Parabolic Partial Differential Equations Using Xnode-Wan, Paul Valsecchi Oliva, Yue Wu, Cuiyu He, Hao Ni

School of Mathematical & Statistical Sciences Faculty Publications

Due to the curse of dimensionality, solving high dimensional parabolic partial differential equations (PDEs) has been a challenging problem for decades. Recently, a weak adversarial network (WAN) proposed in Zang et al. (2020)[17] offered a flexible and computationally efficient approach to tackle this problem defined on arbitrary domains by leveraging the weak solution. WAN reformulates the PDE problem as a generative adversarial network, where the weak solution (primal network) and the test function (adversarial network) are parameterized by the multi-layer deep neural networks (DNNs). However, it is not yet clear whether DNNs are the most effective model for the parabolic …


Spatial Variation Of False Map Turtle (Graptemys Pseudogeographica) Bacterial Microbiota In The Lower Missouri River, United States, Joseph D. Madison, Madeline M. Butterfield, Drew R. Davis, Jacob L. Kerby Aug 2022

Spatial Variation Of False Map Turtle (Graptemys Pseudogeographica) Bacterial Microbiota In The Lower Missouri River, United States, Joseph D. Madison, Madeline M. Butterfield, Drew R. Davis, Jacob L. Kerby

School of Earth, Environmental, & Marine Sciences Faculty Publications

Turtle populations around the world are continually confronted with changing environments that affect their ecology and conservation status. Among freshwater turtles, population dynamics are thought to be mediated by complex yet often cryptic causes. One recent direction of focus in addressing these causes is the turtle-associated microbiota. In turtles, the gut- associated microbiota is of exceptional interest due to its continual association with host species under changing conditions. Diet-based fluctuations and changes in microbial diversity may correspond to varying external environments at both the individual and population level. Environmental responses are of particular interest due to the anthropogenic changes that …


Search For Continuous Gravitational Wave Emission From The Milky Way Center In O3 Ligo-Virgo Data, R. Abbott, H. Abe, F. Acernese, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Aug 2022

Search For Continuous Gravitational Wave Emission From The Milky Way Center In O3 Ligo-Virgo Data, R. Abbott, H. Abe, F. Acernese, M. G. Benjamin, Teviet Creighton, Mario C. Diaz, F. Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We present a directed search for continuous gravitational wave (CW) signals emitted by spinning neutron stars located in the inner parsecs of the Galactic Center (GC). Compelling evidence for the presence of a numerous population of neutron stars has been reported in the literature, turning this region into a very interesting place to look for CWs. In this search, data from the full O3 LIGO-Virgo run in the detector frequency band [10,2000]  Hz have been used. No significant detection was found and 95% confidence level upper limits on the signal strain amplitude were computed, over the full search band, with …


Search For Subsolar-Mass Binaries In The First Half Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang Aug 2022

Search For Subsolar-Mass Binaries In The First Half Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M⊙ and 1.0  M⊙ in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr−1. This implies an upper limit on the merger rate …


A Comparison Of Statistical Methods For Modeling Count Data With An Application To Hospital Length Of Stay, Gustavo Fernandez, Kristina Vatcheva Aug 2022

A Comparison Of Statistical Methods For Modeling Count Data With An Application To Hospital Length Of Stay, Gustavo Fernandez, Kristina Vatcheva

School of Mathematical & Statistical Sciences Faculty Publications

Background

Hospital length of stay (LOS) is a key indicator of hospital care management efficiency, cost of care, and hospital planning. Hospital LOS is often used as a measure of a post-medical procedure outcome, as a guide to the benefit of a treatment of interest, or as an important risk factor for adverse events. Therefore, understanding hospital LOS variability is always an important healthcare focus. Hospital LOS data can be treated as count data, with discrete and non-negative values, typically right skewed, and often exhibiting excessive zeros. In this study, we compared the performance of the Poisson, negative binomial (NB), …


Sar Study Of Niclosamide Derivatives In The Human Glioblastoma U-87 Mg Cells, Shizue Mito, Benxu Cheng, Benjamin A. Garcia, Daniela Gonzalez, Xin Yee Ooi, Tess C. Ruiz, Francisco Xavier Elisarraras, Andrew Tsin, Sue Anne Chew, Marco A. Arriaga Aug 2022

Sar Study Of Niclosamide Derivatives In The Human Glioblastoma U-87 Mg Cells, Shizue Mito, Benxu Cheng, Benjamin A. Garcia, Daniela Gonzalez, Xin Yee Ooi, Tess C. Ruiz, Francisco Xavier Elisarraras, Andrew Tsin, Sue Anne Chew, Marco A. Arriaga

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

Glioblastoma is a lethal malignant brain tumor, and the development of efficient chemotherapeutic agents remains an urgent need. Niclosamide, an anthelmintic drug, which has been used to treat tapeworm infections more than 50 years, has recently attracted renewed attention due to its evident anticancer activities. It has been shown that niclosamide induces cytotoxicity in human glioblastoma U-87 MG cells corresponding with increased protein ubiquitination, ER stress, and autophagy. Furthermore, niclosamide showed down regulation of multiple pro-survival signaling pathways including Wnt/β-catenin, PI3K/AKT, MAPK/ERK, and STAT3, which further caused reduction of U87-MG cell viability. However, the molecular mechanisms of niclosimide and its …


Towards Sustainable Cities: Life Cycle Cost Analysis Of The Construction Of A Novel Wastewater Management System, Bibhas B. Tanmoy Aug 2022

Towards Sustainable Cities: Life Cycle Cost Analysis Of The Construction Of A Novel Wastewater Management System, Bibhas B. Tanmoy

Theses and Dissertations

Wastage of water is one of the most common environmental issues in the modern era. However, if this level of usage can be controlled, or recirculated properly, the wastage can be lowered down to a very minimum. In the conventional residential plumbing system, blackwater and greywater gets mixed and goes through the same sewage pipe. This mixture turns the whole wastewater amount into blackwater, which requires complex treatment before discharge. Greywater on the other hand can be discharged to waterbodies requiring almost zero treatment. In this study, a new wastewater management method is proposed where the plumbing system is split …


Tree Ring Reconstructions Of Streamflow For The Lower Rio Grande Valley Of Texas, Adedolapo Mutiyat Adeyanju Aug 2022

Tree Ring Reconstructions Of Streamflow For The Lower Rio Grande Valley Of Texas, Adedolapo Mutiyat Adeyanju

Theses and Dissertations

The Rio Grande River is a major water source for people living within the USA-Mexico border. The Rio Grande River has its headwaters in the San Juan Mountains in Colorado and the Sierra Madre Occidental in Mexico before flowing into Texas through El-Paso. The water supply issues facing the Lower Rio Grande Basin (LRGB) are extremely complex from international restrictions to severe climate change. The river shares its flow between the U.S.A and Mexico based on the provisions of the 1944 treaty between the U.S.A and Mexico. The LRGB flow is regulated by releases from Falcon and Amistad Reservoirs managed …


Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie Aug 2022

Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie

Theses and Dissertations

Hydrogen is one of the most promising alternatives and clean fuel sources, but it has faced several hurdles due to storage and transportation issues. Several methods have been proposed, developed, and are being improved. Key among these is the use of polymers as safe hydrogen storage media.

This work investigated the polymerization of methyl vinyl ketone using different concentrations 2,2’-Azobis(2-methylpropionitrile) as the initiator in a free radical polymerization mechanism. There was a subsequent analysis of the effect of the initiator concentration on the conversion rate and the molecular weight of the polymers produced with the help of Gel permeation chromatography. …


A Small Wolf Eats A Large Apple: An Experimental Investigation Of The Temporal Processing Of Conceptual Magnitudes, Carolina Alvarez Aug 2022

A Small Wolf Eats A Large Apple: An Experimental Investigation Of The Temporal Processing Of Conceptual Magnitudes, Carolina Alvarez

Theses and Dissertations

When individuals are presented with two options and are asked to select the conceptually larger item, a size congruity effect is usually observed. A size congruity effect is present in comparison tasks when congruent stimuli, whose physical size and conceptual size match, are compared much faster than incongruent stimuli, whose physical size and conceptual size do not match. The current study used images and words as stimuli to investigate the two competing hypotheses for the size congruity effect using delta plots. Positive delta plots were observed when response time for incongruent items was compared to congruent items, providing evidence of …


Effects Of Macronutrients Intake And Physical Activity On Childhood Obesity Of Hispanic Children, Prosanta Barai Aug 2022

Effects Of Macronutrients Intake And Physical Activity On Childhood Obesity Of Hispanic Children, Prosanta Barai

Theses and Dissertations

Obesity has become more ubiquitous during the past few decades, and still, its prevalence is increasing. It is in every population in the world and all regions, including rural parts of low and middle-income countries. In the USA, regardless of age, the severity of obesity is no different from the global trend. Although numerous pieces of literature are available, that tried to find answers to some pressing issues like how obesity can be controlled, but there is little to no study focused on younger children, especially the 4-6-year-old Hispanic population. Our study aimed to determine the causal path among literature …


Quantization For A Nonuniform Triadic Cantor Distribution, Asha Barua Aug 2022

Quantization For A Nonuniform Triadic Cantor Distribution, Asha Barua

Theses and Dissertations

The quantization scheme in probability theory deals with finding a best approximation of a given probability distribution by a probability distribution that is supported on finitely many points. Let P be a Borel probability measure on R such that P := 1/4 P◦ S1−1 + 1\2 P◦ S2−1 + 1/4 P◦ S3−1, where S1, S2 and S3 are three contractive similarity mappings such that Sj(x) = 1/5x+2(j−1)/5, for all x ∈ R. For this probability measure, in this thesis, we determine the optimal sets of n-means and the nth quantization errors for …


Quantifying And Predicting Drought Performance In Woody Semi-Arid Seedlings In South Texas: Implications For Enhancing Drought Resilience In Restoration, Zarek Contreras Aug 2022

Quantifying And Predicting Drought Performance In Woody Semi-Arid Seedlings In South Texas: Implications For Enhancing Drought Resilience In Restoration, Zarek Contreras

Theses and Dissertations

Increasingly frequent and severe droughts in the Lower Rio Grande Valley National Wildlife Refuge have been observed to cause large variation in species-specific mortality patterns in young seedlings, spanning 6 – 43 % mortality within the first year. To understand the underlying mechanisms behind this, we subjected seedlings of five woody semi-arid species (Celtis pallida, Forestiera angustifolia, Sideroxylon celastrinum, Phaulothalmnus spinescens, and Zanthoxylum fagara) to a point-of-no-return drought experiment in order to (1) identify potential metrics capable of predicting species wilting and mortality responses, and (2) to understand the underlying mechanisms that correspond to species drought performance …


Mathematics Teachers’ Working With Cooperative Learning, Jaime Gomez Aug 2022

Mathematics Teachers’ Working With Cooperative Learning, Jaime Gomez

Theses and Dissertations

Teaching styles vary greatly amongst educators. One being extensively researched and highly discussed is the method of cooperative learning. Although many studies have shown the benefits of incorporating cooperative learning into classrooms, it has not been a widely used method of teaching in high school mathematics classrooms. This study explores some of the efforts that teachers, who utilize cooperative learning in their classrooms, make to implement cooperative learning lessons successfully. Furthermore, this study also explores the challenges these teachers have encountered when using cooperative learning. Data was collected qualitatively by interviews and surveys from six in-service high …


Disruptions In International Trade: A Perspective On Ports Of Entry And Supply Chain Resilience, Jose A. Jara Jr. Guerrero Aug 2022

Disruptions In International Trade: A Perspective On Ports Of Entry And Supply Chain Resilience, Jose A. Jara Jr. Guerrero

Theses and Dissertations

United States (U.S.) ports of entry (POEs) and supply chains (SCs) have a prominent trade relationship with a growing desire to improve their operational capabilities. Though trade deals like the U.S.-Mexico-Canada (USMCA) agreement have facilitated trade between these countries, U.S. Customs and Border Protection (CBP) at POEs have also increased security inspections, following the September 11th incident, which have impacted international and global SCs. More recently, the COVID-19 pandemic has caused labor shortages at both sea and land POEs, increasing vessel and commercial vehicle congestion. These POE disruptions have also propagated into the third-party logistics (3PL) of SC networks, which …


Rotational Spectroscopy Of Nonafluoro-Tert-Butyl Alcohol, Zayra Leticia Gonzalez Aug 2022

Rotational Spectroscopy Of Nonafluoro-Tert-Butyl Alcohol, Zayra Leticia Gonzalez

Theses and Dissertations

Nonafluoro-tert-butyl alcohol (NFTBA) is an alcohol being used in medicine and for the analysis of physiochemical and biological properties. Quantum chemical calculations on NFTBA were carried out using cluster computers from the Texas Advanced Computing Center (TACC) at Austin, TX. We scanned the C–C–O–H dihedral angle for 36 steps with each step at 10 degrees at the B3LYP/aug-cc-pVTZ level in order to identify the stable conformations and the energy barriers. The geometry of nonafluoro-tert-butyl was studied using MP2 and B3LYP Density Functional Theory (DFT) with an aug-cc- pVTZ basis set. The calculated rotational constants and dipole moments were used to …


Tap Water Disinfection In The Electrochemical Precipitation Process By Using Novel Conductive Concrete, Md Shoriful Islam Aug 2022

Tap Water Disinfection In The Electrochemical Precipitation Process By Using Novel Conductive Concrete, Md Shoriful Islam

Theses and Dissertations

Electrochemical precipitation (EP) is tested to learn about its impact on disinfectants in tap water. The EP process involves applying electricity through electrodes submerged in water to precipitate dissolved metals like water hardness out without chemical additives. In the study, tap water was tested to learn about EP’s impact on disinfectants. Tap water contains not only hardness but also residual disinfectants. It is very essential for the safety of drinking water against the potential ingress of pathogens before the water reaches the end-users. USEPA mandates that the free chlorine level in drinking water should be 0.2mg/L to 4 mg/L. …