Digital Commons Network^™

Characterization Of Electrically Conductive Inks In Simulated Space Environment, Kazi Md Masum Billah

Open Access Theses & Dissertations

Increasing numbers of satellite missions necessitate a standalone power supply with self-recovery capabilities in case of failure in the space environment. A self-repairing kit was developed with the capabilities to repair the damaged solar array by dispensing conductive inks. Dispensing of conductive materials using direct writing technology to the space environment not only repairs damaged electronic components but also demonstrates the possibilities of manufacturing in outer space. For earth application, properties of direct writing inks have been evolved. In space application, direct writing inks or conductive inks have some issues such as outgassing, vapor pressure, curing etc.Therefore, having the properties …

Seeds Of Neocolonialism In Development Discourse: A Study Of Neoliberal "Megarhetorics" Of Global Development And Ecofeminist Resistance, Moushumi Biswas

Open Access Theses & Dissertations

This paper is based on a case study of www.monsanto.com, the official website of biotech company Monsanto, and transnational voices of resistance as exemplified by eco-critical activist Vandana Shiva. My rhetorical inquiry concerns the future of the global farming sector and allows for an interdisciplinary exploration of transnational development discourse through the overlapping but complementary lenses of ecofeminism and critical discourse analysis (CDA). The purpose of my study – spanning rhetoric, composition, critical theory, cultural theory, communication studies, business ethics, and postcolonial studies – is to trace new notions of discourse creation in the 21 st century using a combination …

Theoretical Acoustic Absorber Design Approach For Lox/Lch4 Pintle Injector Rocket Engines, Jonathan Candelaria

Open Access Theses & Dissertations

Liquid rocket engines, or LREs, have served a key role in space exploration efforts. One current effort involves the utilization of liquid oxygen (LOX) and liquid methane (LCH4) LREs to explore Mars with in-situ resource utilization for propellant production. This on-site production of propellant will allow for greater payload allocation instead of fuel to travel to the Mars surface, and refueling of propellants to travel back to Earth. More useable mass yields a greater benefit to cost ratio. The University of Texas at El Paso's (UTEP) Center for Space Exploration and Technology Research Center (cSETR) aims to further advance these …

4-Nonylphenol Induces Neurodegeneration By Altering Cytoskeleton, Cynthia Carreon

Open Access Theses & Dissertations

4-nonylphenol (4-NP), an endocrine-disrupting compound (EDC), has been shown to affect brain development and may cause neurodegeneration. In the environment, 4-NP arises as a degradation product of alkylphenol polyethoxylates, compounds widely used as nonionic surfactants in commercial production, as well as in herbicides, pesticides, polystyrene plastics, and paints and has been shown to undergo a high level of accumulation in biological tissues. However, the mechanism by which 4-NP exerts its effect is not understood. Recent results from our laboratory indicate that Gβγ, an important component of the G protein-signaling pathway, induces neuronal outgrowth and differentiation by modulating microtubule (MT) assembly, …

Organic-Inorganic Graphite And Transition Metal Dichalcogenide Based Composites For 3d Printing, Jorge Alfredo Catalan Gonzalez

Open Access Theses & Dissertations

This project was multipronged to help fuse together topics of additive manufacturing and two-dimensional (2D) layered materials, and studying the mechanical and electrical properties of the composites produced. The composites are made from the thermoplastic polymer acting as a matrix and the graphite and 2D transition metal dichalcogenides (TMDs) serving as the filler or reinforcement. Different concentrations of TMD's were added to the matrix to study the effect of composition on the mechanical and electrical properties. To shed insights into the mechanical properties, test coupons were produced as "dog bone" structures for tensile testing using the ASTM D638 type 5 …

From The Fangs Of Monsters: Gender, Empire, And Civilization In The Pacific, 1800-1850, Michael David Chavez

Open Access Theses & Dissertations

As the nineteenth century commenced, contact between Pacific Islanders and Anglo-Americans increased as did the concern for what resulted from those interactions. In the United States, antebellum restrained men––those who upheld their Protestant faith, self-reliance, and familial values––used ideals of gender to combat the perceived “savagery” of Pacific Islanders and the corruption of American sailors among them. In the mission field, restrained men consciously sought after Anglo-American women’s influence often believing them to be the moral authority of a softer form of empire. This particular form of empire was not government led; nor did it entail the immediate conquest of …

The White Rose Movement: The Rhetorical Situation And Rhetorical Stances Surrounding The Six Anti-Nazi/Anti-War Leaflets, Veronica Ruth Cruz

Open Access Theses & Dissertations

This study focuses on the White Rose Movement's six anti-war/anti-Nazi leaflets the Movement produced and distributed between June 1942 and February 22, 1943 in Munich, Germany. The persuasiveness of the non-violent resistance Movement was analyzed and discussed using a Bitzerean and Booth rhetorical analysis. Though numerous active and passive social protests, such as marches, music, and rallies, have been examined rhetorically in the past, the research surrounding the written form of protest is minor. In direct regards to the White Rose Movement, specifically, the Movement has yet to be examined through a rhetorical lens until now. The Movement and its …

Cultivating Social Capital In Undergraduate Research: Key Sources And Distinctions By Gender, Heather Ann Daniels

Open Access Theses & Dissertations

Women are outpacing men in overall educational attainment, however this is not the case in science, technology, engineering, and mathematics (STEM) fields when women fall behind men. Establishing strong social connections is important to retention in STEM fields and persistence in the STEM pipeline. This study qualitatively examines what serves as social capital in STEM-focused undergraduate research and how social capital is accrued and deployed differently by men and women in ways that could be contributing to the gender gap in STEM. 17 students participating in external summer research programs at 12 different universities were interviewed at 3 points in …

Methods For Producing Graphene From Petroleum By-Products, Eva M. Deemer

Open Access Theses & Dissertations

N/A

A Study Of Hippocampal Microglia Distribution In Pre-Adolescent Mice Chronically Exposed To Lead, Salvador Dominguez

Open Access Theses & Dissertations

Background: Lead is a major unresolved child health hazard. Children are uniquely vulnerable to the effects of lead exposure, which include disruption of brain development and brain function. How lead exposure alters brain development and brain function is not currently known. Our laboratory has been developing a mouse model to understand effects of low-level lead exposure in the developing brain. In previous studies, we have shown that early chronic low level lead exposure diminished the number of microglia in the dentate gyrus region of the hippocampus, an area responsible for learning and memory. Building on the results of the previous …

Trade Cluster Impacts On Southern Border Transportation Costs, Ernesto Duarte Ronquillo

Open Access Theses & Dissertations

This Thesis develops a fixed effect model to analyze the impact of trade clusters on transportation costs. CIF/FOB ratios are utilized as the measures for transportation costs. Grubel-Lloyd and Herfindahl-Hirschman indexes are utilized as variables that identify trade clusters. The focus of this study encompasses four custom districts (El Paso, Laredo, Nogales, and San Diego) located on the southern border of the United-States over the period of 1995-2015. Driscoll-Kraay robust standard errors are calculated for each estimated model. The 9/11 terrorist attack effects are taken into account in the fixed effect model. Empirical results suggest that trade clusters have a …

Influence Of Overlay Thickness On Interface Bonding, Aliasghar Dormohammadi

Open Access Theses & Dissertations

Overlaying is an efficient and proven pavement preservation approach for flexible pavements. The overlay thickness varies from 1 in. to 4 in. depending on the conditions of the existing pavement, financial resources, etc. In the recent decade, financial constraints in conjunction with the push for pavement preservation, the overlay thickness is being reduced to less than an in. The ultra-thin overlay is a new cost-effective method that can be used to preserve functional pavement problems and provide satisfactory ride quality. Although studies have been conducted to evaluate pavement systems using numerical simulation, the research in the area of evaluating existing …

Structural Modifications In The Rbxcs1-Xpo 4 (0 ≤ X ≤ 1) Superprotonic Conductor Series: A Single-Crystal X-Ray Diffraction And Impedance Spectroscopy Study, Andres Jose Encerrado Manriquez

Open Access Theses & Dissertations

We have used single-crystal X-ray diffraction measurements to investigate the structural modifications induced by Rb-doping of the protonic conductor CsH2PO4. Data collected on the RbxCs 1-xH2PO4 (0 ≤ x ≤ 1) series shows that the monoclinic P21/m CsH2PO4 presentation persists upon Rb-doping up until x = 0.8. Rb0.8Cs0.2H2PO 4 exhibits a previously unreported P21/c monoclinic structure, where the mirror plane is lost and disorder is present in the PO4 tetrahedra even at room temperature. Higher levels of x display a tetragonal I-42d unit cell isomorphic with the known structure of RbH2PO 4. The temperature dependence of the proton conductivity determined …

/S/ Aspiration In Ciudad Juárez And Speech Accommodation, Sandra Esparza

Open Access Theses & Dissertations

Phonological variation in Spanish mainly affects consonants rather than vowels. One of the consonants that is part of the variation is /s/ (Hualde, 2005). The phonological process that commonly affects /s/ is aspiration and is defined as the absence of the oral place features while a glottal friction is retained (Clements, 1985). Aspiration occurs in about half of the Spanish-speaking world (Terrell, 1981) and constitutes one of the most useful stylistic and sociolinguistic variables that characterizes Spanish social dialects and discourse models (Lipski, 1991). Aspiration is present in several Spanish dialects in Latin America (Resnick, 1975). In the specific case …

On-Orbit Autonomous Repair: Systems Design And Project Management Of The Orbital Factory Ii Cube-Satellite, Mike Louis Everett

Open Access Theses & Dissertations

In 2016, a group of faculty, staff and students from the University of Texas at El Paso submitted a formal entry to the ULA CubeCorp competition to launch a 1U Cube Satellite into Orbit. In September of 2016, the team was awarded a launch opportunity to a prestigious GTO orbit to test and validate electrically conductive printing on within the Van Allen Radiation belts. This Dissertation is focused upon the management plan and specific decision that were implemented to accomplish this goal within a one year time frame and on a conservative budget.

In 2018 this satellite will launch aboard …

Octopamine In Sexual Behavior, Ana Isabel Fernandez

Open Access Theses & Dissertations

Octopamine is a biogenic amine neuromodulator present in neuronal and non-neuronal tissues in invertebrates (Roeder, 1999). It modulates numerous physiological processes such as motivation, pheromone response, olfaction, ovulation, learning and memory. Octopamine together with its precursor tyramine have roles restricted only to invertebrates (Roeder, 1999). It is believed that octopamine is the invertebrate homolog of norepinephrine, a catecholamine present in mammals that acts as a neuromodulator in the sympathetic and central nervous systems. Both octopamine and norepinephrine are derived from the same amino acid tyrosine and are monoamine neurotransmitters. The main objective of this study is to understand the role …

Predicting Individualized Treatment Effects Via Random Forests Of Interaction Trees, Annette Pena Franco

Open Access Theses & Dissertations

Abstract Not Available

A Behavioral And Neuroimmune System Model Of The Effects Of Chronic Low-Level Lead Exposure In Young Male C57bl/6j Mice, Mayra Gisel Flores-Montoya

Open Access Theses & Dissertations

Chronic low-level lead exposure reduces memory in children however the brain mechanisms mediating these effects are not known. In previous studies we showed that early lead exposure reduced olfactory memory and exploratory behavior in young mice, and reduced microglia cell density in hippocampus/dentate gyrus. The present studies aimed to identify additional behavioral tests that were sensitive to early low-level lead exposure in young mice; and to examine whether microglia upregulated factors known to promote cell migration. Seventy-two C57BL/6J male mice were exposed to 0 ppm (controls), 30 ppm (low-dose), or 430 ppm (high-dose) of lead acetate via dams' milk from …

Behavior Of Sandwich Composite Cores Under Extreme Conditions, Carlos Daniel Garcia Perez

Open Access Theses & Dissertations

The use of composite structures for diverse applications have become of great interest for scientists and engineers thanks to the advantages that they may offer in comparison to conventional materials. In the case of sandwich composite structures, its mechanical properties can be tailored according to the necessities through the correct selection of a core and facesheets. In combination, this "new" material will have superior properties compared to traditional materials such as steel and aluminum. For arctic exploration, a core with low moisture absorption, low density, and resistance to extreme, low temperatures is desirable for this type of application. This Thesis …

Evaluation Of Pertussis Knowledge Within The Child Daycare Staff And Management In The El Paso, Texas, Diana Jaqueline Gomez

Open Access Theses & Dissertations

BACKGROUND: Child daycare centers have an enormous influence on the children's health, which is important to maintain daycare staff and management informed on how to prevent communicable diseases, such as pertussis. Bordetella pertussis (Bp), the causative agent of whooping cough, is a small gram-negative bacterium that infects the nasopharynx of humans, which are the only reservoir. Bp is a highly contagious respiratory disease, which continues to be a severe disease in infants. The disease affects all ages and is easily transmitted from person to person, through respiratory droplets. Even though there is a vaccine available for all ages there are …

My First Moon, Guadalupe Garcí­A Mccall

Open Access Theses & Dissertations

In his book, The Storytelling Animal, Jonathan Gottschall states that a "Story's role in human life extends far beyond conventional novels or films. Story, and a variety of storylike activities, dominates human life" (8). This quote illustrates how important writing and writers are in our society. This idea resonates with my deeply felt need to create meaningful work, work that will make its way into the fabric of our social structure, work that will improve and elevate life for humanity and the world our children will inherit.

One thing that is always of utmost concern to me as a writer …

Studies On Woven Carbon/Vinyl Ester Composites: Environmental Effects, Joining And Hybridization, Ricardo Garcia

Open Access Theses & Dissertations

The incessant demand for fiber reinforced polymer composites, or FRPCs, in industrial applications which desire materials that possess high strength-to-weight ratios, generates a theory-to-practice void which must be filled with scientific research. In this Thesis, woven carbon/vinyl ester composites are studied under a wide spectrum of settings and conditions. The adverse effects of sea water environment and arctic temperatures on such mentioned composites are explored in the form of moisture uptake, impact on flexural modulus, strength and structural damage. It was found that sea water saturation in general degrades the flexural strength up to 19.45%, and arctic exposure and combined …

Integrating Manufacturing Geometric Imperfections In The Inelastic Behavior Modeling Of Joints Used In Three-Dimensional Structures, Alfonso Andres Garcia

Open Access Theses & Dissertations

Three-dimensional structures follow design practices on the common assumption that joints are either rigid, or pinned. However, the non-linear behavior of engagement of the joints is required to be incorporated into the analysis. This research is intended to incorporate manufacturing geometric imperfections into the mechanical analysis of reticulated space structures jointing systems. Imperfect jointing systems deviate from the as-designed models in such a way that the location of the connecting surfaces does not follow the designed interaction path between the component elements. However, current structural analysis methodologies do not consider manufacturing geometric imperfections and often fail to consider the stresses …

The Risk Principle Paradox: A Multilevel Approach To Examine Which High-Risk Offenders Successfully Change During Rehabilitation Programs, Cole Higley

Open Access Theses & Dissertations

The empirically supported risk principle demonstrates that correctional agencies can reduce recidivism by providing greater supervision and rehabilitation services to higher-risk offenders. The current study examined the paradox that offenders with the greatest risk to reoffend also have the most potential to successfully change; yet, little research has examined why some high-risk offenders succeed in programs, while others do not. Analyses examined whether certain demographic, motivation, and rehabilitative group features were related to program performance and post-release recidivism. Results showed that in certain rehabilitation types, statistically significant interactions were observed, such that the relationship between individual risk and outcome (either …

Spectroscopic And Microscopic Analysis Of Graphene For Sensor Applications, Tamanna Tasneem Khan

Open Access Theses & Dissertations

As a two-dimensional material, graphene shows very good thermal and electrical conductivities, which, with its unique optical properties, makes it suitable for a variety of applications. In this study, we present detailed investigations by confocal Raman and Drude model analysis of the material's changes and improvements, as it transitioned from 3D graphite to 2D graphene. Besides Raman spectral recording, which can detect single, a few, and multi-layers of graphene, confocal Raman mapping allows distinction of such domains and direct visualization of material inhomogeneity. Moreover, far-infrared transmittance measurements, which are related to electrical conductivity, demonstrate a distinct increase of conductivity with …

Cost-Effective Recovery Of Concentrated Cooling Tower Blowdown Using The Cerro Process, Lindsey Nicole Larson

Open Access Theses & Dissertations

The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) process is a seawater-RO unit that can cost-effectively achieve extremely high recoveries from water high in silica, carbonate and sulfate concentrations. This relatively new technology takes advantage of the induction time of potential foulants to recover more water than what is normally achievable with a conventional desalination system. The scope of the project was to evaluate the efficiency of the CERRO process as a pilot study using cooling tower blowdown which varied in water quality parameters daily. It was found that the CERRO pilot could successfully achieve 85% recovery, and the main limitation …

Identification And Characterization Of Tumor-Associated Antigens (Taas) And Anti-Taas Autoantibodies As Biomarkers In Immunodiagnosis Of Human Osteosarcoma By Serological Proteome Analysis (Serpa), Jitian Li

Open Access Theses & Dissertations

Osteosarcoma (OS) is the most common highly malignant primary solid bone-tumor. Despite its relatively low incidence rate among overall cancers, it remains one of the most harmful primary malignant tumors in childhood and adolescence. Although some tumor markers like mutant p53 can be potentially used as biomarker to detect OS, its extensive association with the clinical outcome is poorly understood. The establishment of a methodology to identify patient with early stage of OS remains to be investigated. It is now evident that serum autoantibodies against tumor-associated antigens (TAAs) could be used as serological cancer biomarkers in types of cancers, which …

Evaluation Of A Gender-Relevant Physical Activity After-School Program, Vianay Lopez

Open Access Theses & Dissertations

Background: Physical activity rates have decreased in the past 30 years. Physical activity rates decline further among girls as they reach adolescence, yet studies suggest girls are more inclined to participate in moderate-to-vigorous physical activity (MVPA) while among peers. When in close social networks, girls who have more physically active friends report being more active themselves. Several mentor-based programs throughout the United States have increased physical activity among preadolescent girls, indicating that gender-relevant physical activity programs may reverse their declining rates of physical activity.

Purpose: To evaluate if participation in a gender-relevant physical activity after-school program influenced participants' aerobic fitness, …

An Echo Of Swelling Voices, A Meta-Fictional Novella, Adolfo Danilo Lopez

Open Access Theses & Dissertations

Horacio P. is an exiled Nicaraguan American poet living and teaching in Austin, Texas since the 1970s. Despite his enormous reputation and highly supportive wife, he feels incapable to write his last, and best, novel. This novel is about the life of Asdreni, an Albanian poet who was also exiled in Romania during the time before World War II, and his quest to find out who sent him a mysterious box containing the unpublished manuscripts of an unknown poet. One day, Horacio himself also receives a mysterious box containing the unpublished manuscripts of an unknown poet. His novel and his …

Agents Of Global Armament: Analyzing Masculinity And Militarism In "Captain America" And The Marvel Cinematic Universe, Jodie Nikole Lout

Open Access Theses & Dissertations

In the current zeitgeist, there has been a surge in the popularity of superhero movies. For many decades, Hollywood has been producing films that propagate ideologies of hyper-masculinity and militarism. This study suggests that it is possible to analyze the recent character "Captain America" as propaganda for militarism and hyper-masculinity. This study proposes to analyze the character in the films Captain America: The First Avenger (2011), The Avengers (2011), Captain America: The Winter Soldier (2014), Avengers: Age of Ultron (2015), and Captain America: Civil War (2016).