Digital Commons Network^™

Zinc-Mediated Regulatory Function Of Psd-95 On Nmdar At Post-Synapses, Luis F. Acosta

Theses and Dissertations

Postsynaptic density-95 (PSD-95) is a membrane-associated guanylate kinase that mediates localization of receptors in the excitatory postsynaptic density. It has been reported that PSD-95 mediates postsynaptic localization of NMDA receptors and anchors postsynaptic AMPAR receptors mainly through its postsynaptic membrane targeting by its N-terminal palmitoylation. Recent studies have shown that Ca2+/calmodulin blocks palmitoylation of PSD-95 by binding at the N-terminus of PSD-95, which promotes dissociation of PSD-95 from the postsynaptic membrane and causes loss of surface AMPARs in cultured neurons. Another metal ion zinc is found in various areas of the brain. As an endogenous neuromodulator, zinc plays a role …

An Experimentally Validated Finite Element Model Of Thermal Transient Response Of A Railroad Bearing Adapter, Javier E. Arroyo

Theses and Dissertations

Wayside hot box detectors (HBDs) are devices used to determine the health of railcar components such as bearings, axles, and brakes by monitoring the radiated temperature form these components. HBDs have been instrumental in reducing rail derailments in the decade, but the number of non-verified bearing removals has increased significantly. To combat these limitations, researchers have opted to use wireless onboard sensor devices directly mounted on the bearing adapter. The wireless onboard health monitoring system developed by the University Transportation Center for Railway Safety (UTCRS) utilizes temperature and vibration sensors to detect the condition of rolling stock. However, because the …

Targeting Protein Synthesis In Clostridioides Difficile To Develop Antimicrobial Candidate, Elvira L. Alanis

Theses and Dissertations

Clostridioides difficile is a gram positive, spore forming, obligate anaerobic bacterium that causes Clostridioides difficile infection (CDI) which can result in pseudomembranous colitis and toxic megacolon. In the case of this research a focus on Protein synthesis is made since it is an essential metabolic process and is a validated target for antibiotics. Protein synthesis begins with Initiation which includes the three translation initiation factors. Through the NMR chemical shift assignments, the IF1 structure was determined, and it was found to be composed of a short α helix and five β helixes. A peptide was designed after the short α …

Harvester Ant (Pogonomyrmex Sp.) Seed Preferences And Distribution In A Suburban Setting, Lilly V. Elliott

Theses and Dissertations

Harvester ants (Pogonomyrmex sp.) are omnivorous ants native to Texas and are the main food source for the threatened Texas Horned Lizard (Phrynosoma cornutum). Little research has been conducted on harvester ants in the Lower Rio Grande Valley (LRGV) and their interactions with their environment. For this purpose, a variety of experiments were conducted to better understand these interactions and preferences. In CHAPTER I, suburban harvester ants were exposed commonly used cover crop seeds in the LRGV and inoculated seeds via seed depots over the course of 24 hours. We found that harvester ants do …

Discourses Surrounding Specific Learning Disability In Reading: An Exploration Across Special Education Policies, Martha M. Briseno

Theses and Dissertations

Individuals with disabilities have been subjected to deficit models that have led to unfair treatment, exclusion, and an unfitting education for years. Historical factors have informed policies toward the educational treatment and rights of individuals with disabilities in the United States since the 1600s. Before the enactment of The Education for All Handicapped Children Act (EAHCA) in 1975, it was common practice for children with disabilities to be segregated, excluded, and given an unsuitable education in comparison to their nondisabled counterparts. Throughout history, the language used in legislation and educational documents have compartmentalized students with disabilities based on …

Effects Of Tributyltin Exposure On 8-Ohdg And Dsdna Expressions, Oxidative And Nitrative Stress In The American Oyster, Crassostrea Virginica, Mohan Kumar Dash

Theses and Dissertations

Environmental pollution increases due to anthropogenic activities. Different types of pollutants and/or chemicals impair growth, reproduction and development in aquatic organisms. Tributyltin (TBT, an organotin compound) is a tremendously toxic substance which widely uses as antifouling paints used in boats, hulls, and ships. The toxic effect of TBT is well documented in teleost species. The American oyster (Crassostrea virginica) is an ideal shellfish species to study on TBT exposure DNA lesion and oxidative/nitrative stress. In this study, the effects of TBT on 8’-hyrodxy-2’-deoxyguanosine (8-OHdG, a molecular marker), dsDNA, dinitrophenyl protein …

Cloth-Water Interaction For Air Humidification In Hdh Desalination, Alejandro Corona Martinez

Theses and Dissertations

The humidification-dehumidification (HDH) desalination technology is a promising desalination process that has the potential to provide cost-effective and environmentally friendly saltwater desalination, especially when combined with renewable energy sources. The working principle mimics the natural hydrologic cycle, involving the evaporation of seawater into water vapor (humidification) and condensation into freshwater (dehumidification). HDH desalination can be land-based or ocean-based. Some of the advantages of ocean-based systems include removing pretreatment processes, utilization of ocean energy (i.e. thermal and kinetic), and eliminating brine production. This study focuses on the design and experimental testing of a novel humidifier …

Postprandial Hemodynamics In Hispanics With And Without A Family History Of Type 2 Diabetes, Gabriel Alejandro Figueroa

Theses and Dissertations

Hispanics of the Rio Grande Valley (RGV) have the highest rates of obesity and type 2 diabetes (T2D) in the country, conditions often associated with cardiovascular disease and increased mortality. This study investigated the physiological factors affecting postprandial hemodynamic responses differently between FH+ and FH- groups. Thirty-one healthy Hispanic individuals volunteered in this study. Overall, FH+ individuals had higher pressures at rest compared to FH-, However, these differences were not statistically significant. When controlling for blood chemistries such as blood glucose, cholesterol, lipoproteins, and triglycerides, family history appears to have no effect on fasted or postprandial hemodynamics and pulse wave …

Huérfanos: A Memoir, Mauricio Garcia

Theses and Dissertations

If you look hard enough, there are stories of children in foster care. Tales of their plight, longing for love, the love of their parents, love from the foster care system, or a foster care family. However, despite their existence, so much is left in the unknown. The story of how this child’s life came into the world, what outcomes transpired for a parent to give up a child, and the journey the child may have to take for closure. Answers to the why. Why was I given up, why was I not sought out, why did my family …

Non-Negative Discriminative Data Analytics, Md Imrul Kaish

Theses and Dissertations

Due to advancements in data acquisition techniques, collecting datasets representing samples from multi-views has become more common recently (Jia et al. 2019). For instance, in genomics, a lymphoma patient’s dataset may include data on gene expression, single nucleotide polymorphism (SNP), and array Comparative genomic hybridization (aCGH) measurements. Learning from multiple views about the same objective, in general, obtains a better understanding of the hidden patterns of the data compared to learning from a single view data. Most of the existing multi-view learning techniques such as canonical correlation analysis (Hotelling et al. 1936) and multi-view support vector machine (Farquhar et …

Nanostructured Materials For Biomedical Applications, Silverio Lopez

Theses and Dissertations

Nanotechnology has been used in an increasing number of applications in biochemistry and molecular biology. Compared to bulk materials, nanoscale materials offer a variety of advantages in applications due to an increased surface-to-volume ratio of the reactants. The unique properties of nanostructured materials and their properties such as stability, reactivity, magnetic response, pressure discharge performance and biocompatibility depend on particle size and shape. This work focuses on a nanoenergetic material composed of Aluminum (Al), Copper II oxide (CuO), and Iodine (I) pentoxide (I2O5), and the biomedical application of nanoscale dextran-coated magnetite (Fe3O4), which was produced using microfluidics to tune particle …

A Narrative Study Of Secondary After-School Robotics Experiences In The Rio Grande Valley: Empowering Students' Academic And Life Skills Through A Constructivist Approach, Lorena Cristina Lopez

Theses and Dissertations

This narrative study investigated the experiences of three Hispanic students in South Texas who participated in after-school robotics programs in secondary school and discover the role these experiences had on their academic and life skills. Data were collected through individual semi-structured interviews with one female participant and two male participants in the Rio Grande Valley. The data were analyzed using the NVivo software to identify patterns and themes amongst the participants followed by a narrative analysis of the participants’ stories, which was guided by the emerging themes.

The findings showed that the secondary after-school robotics programs played a role in …

Total Synthesis Of Mansouramycin A, Abigail M. Zepeda

Theses and Dissertations

In 2009 bioactive compounds from marine Streptomyces species was isolated which resulted in deriving four isoquinoline-quinone alkaloids known as Mansouramycins A-D. There have been reports that there are 36 non-small cancer cells against cytotoxicity in Mansouramycins A-C in lung cancer, breast cancer, melanoma, and prostate cancer cells. Reports that have conducted total syntheses were all specific to a single compound only Mansouramycin A and D. However, in precedent methods, to obtain the derivatives with different substituents are limited when the substituents are on the fused-pyridine ring. Thus, a develop a systematic synthetic methods of isoquinoline-quinones, which are to be able …

Live, Love And Lyft, Daniel Olivarez

Theses and Dissertations

My thesis has a critical introduction that gives a short history of creative nonfiction. I focus on Lee Gutkin’s contribution to creative nonfiction. I also gave some examples of creative nonfiction in my introduction. I included Mary Karr, Lauren Slater, Nathaniel Hawthorne, and William Shakespeare. My thesis contains twelve pieces of writing ranging from narrative nonfiction to poetry, highlighting my experiences growing up in a single parent home in a small border town. I utilize the literary aspects of totemic writing, the journey to the green world, the motif of loss and growing up in a small town, and the …

Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna

Theses and Dissertations

During a high intensity storm events, a series of catastrophic events occur. These catastrophic events include flooding and destruction of infrastructure. Engineers have determined a method to design for high intensity storms based off hydrologic analysis of previous storms. With this data engineers can determine the outflow of major rivers and streams that may impact infrastructure. By determining the watershed engineers can predict the flow of the water and as well as the location of the outfall. In the Rio Grande Valley, water quality is very important because after rain events stormwater from cities is carried out towards the Laguna …

Acoustic And Perceptual Effects Of Mask-Wearing On Voice And Communication In Healthcare Practitioners, Astrid C. Ortiz Garcia

Theses and Dissertations

The purpose of the present study aims to determine the perceptual and acoustic voice effects experienced by healthcare practitioners following prolonged use of face masks during the COVID-19 pandemic. A total of 19 participants were recruited and divided into control and experimental groups. Of these 19, 10 were assigned to the experimental group (E) which required participants to engage in increasing their fluid intake by 1 liter per day, while the remaining 9 were part of the control group (C) and had no additional instructions.

To gather perceptual data, a survey was created and conducted via Qualtrics software, and addressed …

School Leadership That Impacts Student Achievement In Blue Ribbon Schools In The Rio Grande Valley Of Texas, Sonya Y. Rodriguez

Theses and Dissertations

The purpose of this qualitative multiple case study was to determine the leadership actions, behaviors, and practices of effective school leaders in Blue Ribbon Schools in South Texas who resulted in the schools receiving the distinction by the U. S. Department of Education of being a Blue Ribbon School. Data were collected through a series of interviews with principals and teachers from the selected sample of Blue Ribbon Schools in the Rio Grande Valley in South Texas. The interviews were audio recorded, transcribed, and analyzed using inductive coding to determine themes.

Blockchain Value Creation Logics And Financial Returns, Daniel Narh Treku

Theses and Dissertations

With its complexities and portfolio-nature, the advent of blockchain technology presents several use cases to stakeholders for business value appropriation and financial gains. This 3-essay dissertation focuses on three exemplars and research approaches to understanding the value creation logics of blockchain technology for financial gains. The first essay is a conceptual piece that explores five main affordances of blockchain technology and how these can be actualized and assimilated for business value. Based on the analysis of literature findings, an Affordance-Experimentation-Actualization-Assimilation (AEAA) model is proposed. The model suggests five affordance-to-assimilation value chains and eight value interdependencies that firms can leverage to …

Structures And Regulations Of Translation Initiation Factors In Pseudomonas Aeruginosa Protein Biosynthesis To Develop New Potential Antimicrobial Agents, Nicolette Valdez

Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative, multidrug resistant bacterium that has been recognized as the prominent cause of nosocomial infections. Untreated acute and chronic infections associated with P. aeruginosa can develop into other diseases such as pneumonia, otitis externa, and osteomyelitis. P. aeruginosa infections commonly affect immunocompromised individuals such as cystic fibrosis, cancer, and burn patients. The misuse and overuse of antibiotics has contributed to the increased antibiotic resistance in P. aeruginosa and thus has led to an unmet need for discovery of novel antibiotic candidates. Protein biosynthesis is an essential metabolic process occurring in all bacteria and a validated target …

Water Quality Monitoring To Assess Pollutant Loadings In Brownsville Ship Channel Watershed, Ivan Rene Santos Chavez

Theses and Dissertations

The Brownsville Ship Channel (BSC) was listed as an impaired waterway from 2010 to 2018 due to screening levels of bacteria concentration. This study aims to address water quality at the three main tributary ditches draining into Brownsville Ship Channel to model present along with future pollutant loads within Brownsville Ship Channel Watershed. Load Duration Curves (LDCs) and Spatial Explicit Load Enrichment Calculation Tool (SELECT) models were developed to determine if current pollutant loads meet water quality standards stablished by the Texas Commission on Environmental Quality (TCEQ), and to estimate average daily potential E. Coli loading contribution from sub-watersheds within …

Computer Vision And Machine Learning Applications In Cellular Images And Clinical Data, Guochang Ye

Theses and Dissertations

With the progressive development of artificial intelligence (AI), automated analysis has been explored for substituting tedious manual methods in cellular image analysis. Additionally, medical information not included in the conventional statistical methods is now being reconsidered with AI-based personalized medicine. The adaptivity and flexibility of AI ensure its efficiency and accuracy. In this work, computer vision and machine learning (ML) methods under the scope of AI are explicitly investigated and applied to cellular images and clinical data for cytological analysis and to provide diagnosis-based assistance/predictions. Firstly, novel computer vision algorithms achieve cell detection and differentiation estimation on phase-contact microscopic images …

The Effects Of Esl Training On High School Teachers And Their Response To Ells, Benjamin Watt

Theses and Dissertations

This study purposes to uncovering the deficits in secondary teachers’ understanding and practice in the classroom with ELLs. As the study developed it has become clear teachers vary widely on classroom practice and understanding their EL learners. Many teachers feel ill equipped and that the provided professional development is often inconsistent. The study intends to inform education systems of the positive affects of professional development, college courses and self-enrichment on how teachers work with ELLs. The study builds on the research to increase our understanding of the gaps in teaching and how professional development can be most useful for teachers. …

The Form And Function Of Cranial Spines In Fishes, Louis Michael Penrod

Theses and Dissertations

Despite the prevalence of fishes that express cranial spines, quantitative investigations into the function of these spines are rare. Function is often assumed with little or no evidence. Commonly, spine-like structures are considered to be used for defense despite spines potentially being used for other purposes. Here, I took a high-level approach to investigate the morphology and potential functions of cranial spines in over 2000 fishes. Identifying the function of cranial spines in fishes not only informs us as to how these fishes interact with conspecifics, with other species, and with their environment, but also may provide advances in human …

Development Of Simulation Framework For Impact Analysis Of Launch Delays On Lunar Base Station, Giulio Cristello

Theses and Dissertations

Humans have not ventured beyond Earth since the days of the Apollo missions. NASA astronauts were the first and last to set foot on the lunar surface, and it is again thanks to NASA that the initiative to go back to the Moon is moving forward. The Artemis missions will land men and women on the lunar surface with the purpose of establishing a long-term presence on the Moon. The current Artemis Plan includes the Artemis Base Camp, a lunar base stationed on the lunar South Pole. The maintenance of the base will require frequent missions to be performed in …

Holocene Human Influence In The Ecuadorean Amazon, Meghan Mary O'Connor

Theses and Dissertations

The extent to which the spectacular biodiversity of Amazonia has been shaped by Pre-Columbian humans is actively debated. Forests that today appear to be pristine wildernesses may have supported complex human societies as recently as 300 years ago. Understanding human history and the potential successional trajectories that result from site abandonment are important to conservation and policy-making. The Yasuni, is famed for its human and biological diversity and yet its pre-history is poorly known. Lake Añangucocha, a small blackwater lake in northwestern Ecuador, is unusual in that it is not a riverine lake, and has the potential to provide the …

Mindful And Authentic: Examining Leaders’ Impact On The Feedback Environment, Ché Lindsay Albowicz

Theses and Dissertations

The majority of what is currently known about mindfulness at work focuses on the individual benefits of being mindful (see Glomb, Duffy, Bono, & Yang, 2011; Good, et al., 2016), leaving an opportunity to understand the interpersonal impact of mindfulness at work. The current study tested whether mindful individuals, specifically mindful leaders, impact the work experience of their direct reports. Building on initial evidence (Leroy et al., 2015; Nubold, Quaquebeke, & Hulsheger, 2019) and strong theoretical ties (Kernis, 2002), supervisor mindfulness was a significant predictor of direct reports’ perception of authentic leadership behavior. Empathy was tested as a positive other-directed …

Trait Anxiety In The Workplace: A Job Demands-Resources Perspective, Tessly Ann Dieguez

Theses and Dissertations

There is a widely held assumption that anxiety is always bad for job performance, when, in reality, the research findings on anxiety and performance are complex, varied, and inconsistent. Anxiety is extremely common and recently on the rise in the general population, and it can be related to important workplace outcomes such as job performance and well-being. Using the theoretical backdrops of the job demands-resources model (Bakker & Demerouti, 2007, 2018) and the theory of workplace anxiety (Cheng & McCarthy, 2018), this study proposed a model examining the mechanisms through which trait anxiety could lead to lower and higher typical …

Effects Of Orthopedic Implant And Host Bone Properties On Stress-Shielding Induced Osteopenia, Scott Jason Jan Baskerville

Theses and Dissertations

Stress shielding is a term commonly used in literature to describe a bone density reducing phenomenon which occurs due to long-term exposure of bone tissue to sub-homeostatic levels of mechanical stimuli. A number of mechanobiological models ranging in complexity and purpose have been developed with the general overall intent of predicting bone remodeling behavior under a set of prescribed conditions. A previously developed heuristic model is expanded in the present work through model calibration with physiological data and the development of a reduced bone-implant-construct (BIC) mechanical model configurable for patient factors such as age, gender, and associated bone properties. The …

Low-Cost Carriers Versus Legacy Carriers: Passenger Preference During The Covid-19 Pandemic, Aaron Bushelle

Theses and Dissertations

The purpose of the current study was to identify whether passengers had a preference between traveling on low-cost carriers versus legacy carriers during the ongoing pandemic. Building off research conducted by another researcher, several dimensions were identified and utilized within the question items. For this research, the target population was persons residing within the United States who were at least 18 years old and have traveled since the start of the pandemic in the United States in January 2020. A questionnaire was distributed online, and convenience sampling was undertaken. A T-test was conducted, and results indicated that when it came …

Careless Responding In Survey Research: An Examination Of Individual, Situational, And Cultural Characteristics, Michael William Mcferran

Theses and Dissertations

Careless responding is the act of responding to measures with low or little motivation in the form of not properly complying with survey instructions, interpreting survey items, or providing accurate responses (Huang et al., 2012; Meade & Craig, 2012). Careless responding is a concern for all researchers that implement any form of self-report survey methodology within their research as it can have varying effects on data quality and overall data interpretation (Credé, 2010; DeSimone & Harms, 2018; Huang et al., 2015; McGonagle et al., 2016). A comparatively large proporiton of research has examined response bias, whereas a limited, but growing, …