Engineering Commons^™

Formulation Strategies To Enhance Solubility And Permeability Of Small Molecules For Drug Delivery Applications, Pradeep Kumar Bolla

Open Access Theses & Dissertations

All the new chemical entities/drug molecules intended for therapeutic use must be administered using an appropriate delivery system/dosage form to achieve maximum bioavailability. However, designing a drug delivery system is complex as several factors such as lipophilicity, molecular mass, crystallinity, ionic charge, polymorphic forms and hydrogen bonding) affect the solubility and permeability of these molecules. Biopharmaceutics drug classification system (BCS) categorizes the existing drugs into four classes based on the aqueous solubility and membrane permeability and it is reported that >70% of the drugs are poorly soluble and belong to BCS class II and BCS class IV. Several physical, chemical …

Structure-Property-Performance Evaluation Of Refractory Metal Incorporated Gallium Oxide Thin Films For Extreme Environment Applications, Anil Krishna Battu

Open Access Theses & Dissertations

An approach is presented to design refractory-metal (RM) incorporated Ga2O3-based materials with controlled structural, mechanical, and optical properties. A model system based on molybdenum (Mo) doped Ga2O3 (GMO) has been considered to elucidate the combined effect of RM-doping and processing parameters on the properties and oxygen sensor performance of GWO nanomaterials. The molybdenum (Mo) content in Ga2O3 was varied from 0 to 11 at% in the sputter-deposited Ga-Mo-O films. Molybdenum was found to significantly affect the structure and optical properties. While low Mo content (≤4 at%) results in the formation of single-phase (β-Ga2O3), higher Mo content results in amorphization. Chemically …

Supercritical Processed Decellularized Extracellualr Matrix As Regeneration Therapeutics Applying 3d Printing, Seungwon Chung

Open Access Theses & Dissertations

Extracellular matrix has been broadly applied and show great promise in medical applications and tissue engineering. Product of extracellular matrix (ECM) should be treated with decellularization and purification process. Supercritical carbon dioxide treatment is of particular interest for purifying ECM because of its medically available and rapid speed of process. However, it is not fully researched in treatment of biomaterials for tissue engineering. Therefore, we investigated optimal conditions of supercritical carbon dioxide processing in different extracting parameters from porcine adipose tissue. The 3-day, dual treatment including enzymatic decellularization and supercritical fluid extraction of pork adipose tissue were performed. Two types …

3d Printed Alginate-Based Zinc Oxide Nanoparticle Scaffolds For Wound Healing, Carol Cleetus

Open Access Theses & Dissertations

Effective treatment of chronic wounds is essential for the prevention of infection and scar tissue formation, requiring a novel approach to address the limitations of existing options. This study utilizes Calcium Chloride (CaCl2) crosslinked alginate, a common biomaterial widely used in wound dressing, and UV activated Zinc Oxide (ZnO) nanoparticles (NPs) for their potential hydroxyl radical mediated antibacterial applications. ZnO NPs were synthesized by combustion method from Zinc Nitrate Hexahydrate and Sucrose. Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) characterization were used to verify composition and NP size. Terephthalic Acid, used as a fluorescent probe, confirmed the generation of …

Regulation Of Schlafen 11 Expression, Christian Waldemar Corona Ayala

Open Access Theses & Dissertations

Schlafen 11 (SLFN11) is a member a family of proteins that can be found in mammals. Members of this family are involved in important functions. SLFN11 in particular has been identified as a restriction factor for several evolutionarily disparate viruses such as HIV-1 and Flaviviruses and to play an important role in DNA repair, sensitizing cells to chemotherapy. Despite its relevance SLFN11 remains largely uncharacterized. The aim of this research was to achieve a more comprehensive understanding the regulation mechanism of SLFN 11 expression. Before our research, it was only known that type I interferon (IFN) regulates SLFN11 levels. However, …

To Or Through The Skin: A Rational Design Of Transdermal Drug Delivery, Isaac Giovanni Deaguero

Open Access Theses & Dissertations

The skin is the largest organ in the body and plays many crucial roles through diverse functions ranging from protection, temperature regulation, energy storage via fat deposits, and is used to communicate with our surroundings. Various methods have been attempted to deliver drugs to target areas of the skin in effective dosages by a variety of means with limited success. Recently, advances in transdermal drug delivery have offered avenues previously unattainable through conventional means. Some of these new delivery methods have been reviewed, explored and offer promising results with the potential to carve a new avenue in the way therapeutic …

Development And Characterization Of Perovskite Solar Cells For Tandem Device Configuration, Angel Moiseis De La Rosa

Open Access Theses & Dissertations

Photovoltaic devices based on perovskite materials are constantly progressing towards more applicability in large-area panels. In order for perovskite-based photovoltaics to reach reliable and stable commercialization, common issues with the use of perovskite still need to be resolved, including the need to identify fabrication processes that can yield optimal material parameters for better photovoltaic performance. Defining an optimal fabrication process requires that researchers and manufacturers alike come to an agreement regarding perovskite characteristics that result from device operation and material processing. This work focuses on characterizing physical, electrical, and electronic properties of a FAxCs1-xPb(IyBr1-y)3 perovskite, and how some of these …

Thermoanalytical Studies On The Decomposition Of Energetic Ionic Liquids, Alan Esparza

Open Access Theses & Dissertations

Hydrazine has been extensively used as a propellant for space applications for more than half a century. However, its hazardous characteristics cause high storage and handling costs. For this reason, the search for alternatives, the so-called “green monopropellants,” is of great interest. Most green monopropellants are mixtures of an oxidizer and a fuel, and several ionic liquids (ILs) have been proposed for this application. Among them, hydroxylammonium nitrate (HAN) and 2-hydroxylethylhydrazinium nitrate (HEHN) are promising oxidizer and fuel, respectively. The objective of the present work was to clarify the decomposition kinetics of both HAN and HEHN, using thermogravimetric analysis (TGA), …

Independent And Simultaneous Control Of Electromagnetic Wave Properties In Self-Collimating Photonic Crystals Using Spatial Variance, Jesus Javier Gutierrez

Open Access Theses & Dissertations

Photonic crystals are engineered periodic structures that provide great control over electromagnetic waves. One of these mechanisms is self-collimation, in which the electromagnetic wave travels through the photonic crystal along an axis of the lattice without diffracting or spreading. This mechanism of self-collimation is a dispersion phenomenon, which is dependent on the unit cell's physical and geometrical characteristics. An algorithm for generating spatially variant lattices (SVL) was developed that can change geometrical properties in photonic crystals as a function of position, like unit cell orientation, fill fraction, symmetry, and others in a manner that is smooth, continuous, and virtually free …

A Cellulose-Based Biological Sensor For The Quantitative Determination Of Glucose And Glycated Hemoglobin (Hba1c), Gilberto Henao-Pabon

Open Access Theses & Dissertations

ABSTRACT

Importance: Diabetes is a common world-wide disease characterized by insulin resistance and as result there is an increased risk of cardiovascular disease and other metabolic abnormalities, that contribute to irreversible end-organ damage. The cause of diabetes is multifactorial and includes genetic, inflammatory and environmental factors plus lifestyle issues. Because in diabetes there are high levels of glucose and glycated hemoglobin, these molecules are used in clinical settings for the acute and chronic management of diabetic patients.

Objectives: a. To design and build an electrochemical biological sensor using the enzyme Glucose Oxidase (GOX) to detect glucose in biological fluids.

b. …

Remediation And Prevention Of Harmful Algae Blooms (Habs) In Ascarate Lake At El Paso, Texas, Elizabeth Herrera Ortega

Open Access Theses & Dissertations

Ascarate park in El Paso, Texas is an example of an urban ecosystem in the middle of a growing city. It is the largest public-use recreational park in El Paso county and it includes a 48-acre Ascarate lake. The purpose of this study was to prevent harmful algae growth in Ascarate lake using phytoremediation by analyzing different water quality parameters. We installed artificial islands on west cove of the lake with African iris plants to determine the feasibility of remediation to prevent algae blooms in Ascarate lake. Water samples were collected at different points close and away from the islands …

The Study Of The Mouse Schlafen Family Members As Mediators Of Antiviral Activity, Julia Fernanda Hernandez

Open Access Theses & Dissertations

The Schlafen family of proteins was first characterized in 1988, and since then evidence of their relevance in different physiological and pathological situations have been accumulating although at a slow pace. Hence, the biological roles of these proteins remain ill-defined. The expression of these proteins is positively regulated by type 1 interferons, constituting a component of the innate immune response. Functions of these proteins vary from regulation of cell proliferation to restriction of viral infections. Recent studies have implicated SLFN11 and SLFN13 as inhibitors of HIV-1 infection2-4. The mechanism of action of SLFN11 resides in its capacity to regulate the …

Development Of The Payload System And Obc Microcontroller Coding For A Cubic Satellite Performing An Additive Self-Repair Experiment In Space, Eduardo Macias-Zugasti

Open Access Theses & Dissertations

Additive manufacturing, which is also known as three-dimensional printing, in space is one of the most promising technologies advancing current capabilities for in-orbit space manufacturing and assembly. Additive manufacturing contributes to the reduction of cost per kilogram and number of launches, thus facilitating extraterrestrial colonization and deep-space exploration. The state of the art includes advancing efforts inside the International Space Station (ISS). However, the ISS is a controlled environment and, to the best of our knowledge, no spacecraft or satellite has performed additive manufacturing tasks in the extreme environment of outer space. In this work a 1U CubeSat named Orbital …

Compound Vision Approach For Autonomous Vehicles Navigation, Michael Mikhael

Open Access Theses & Dissertations

An analogy can be made between the sensing that occurs in simple robots and drones and that in insects and crustaceans, especially in basic navigation requirements. Thus, an approach in robots/drones based on compound eye vision could be useful. In this research, several image processing algorithms were used to detect and track moving objects starting with images upon which a grid (compound eye image) was superimposed, including contours detection, the second moments of those contours along with the grid applied to the original image, and Fourier Transforms and inverse Fourier Transforms. The latter also provide information about scene or camera …

Velocity Measurements Using A Piezoelectric Plate As A Sensor, Paul Perez

Open Access Theses & Dissertations

In this study, the voltage output from a piezoelectric sensor placed in a test section is used to predict flow velocity changes. The piezoelectric made of PZT is thought to be advantageous due to its fast response time, potential durability at higher temperatures, and self-powered characteristics. Having said that this sensor could be implemented into the Hybrid Performance Project built by NETL to characterize and mitigate the probability of compressor surge and stall. The problem arises because of the added large volume between compressor and gas turbine and resultant changes to system fluid dynamics. The effect of the piezoelectric sensor …

Investigation Of Iron Doped Gallium Oxide (Ga-Fe-O) System: Structure Property Relationship And Performance Evaluation For Optical And Catalytic Applications, Swadipta Roy

Open Access Theses & Dissertations

From September 2012 to May 2015, a phenocam monitored the seaward edge of a protected mangrove forest. Calculated GCC revealed seasonal greening patterns of a mangrove species, Rhizophoa apiculata, and an overall increase in the GCC, suggesting mangrove expansion. In comparing temperature and precipitation effects, it was found that this particular mangrove species had a greening optima at temperatures between 28°C and 28.5°C, and greening and canopy development response lag time of 10 weeks in response to precipitation. Tree saplings were monitored and showed to grow by 50%, mostly during a three month period during the rainy season. The establishment …

Design And Characterization Of Thermal Inkjet Bioprinted Constructs For The Treatment Of Diabetic Foot Ulcers And Other Wound Healing Impaired Conditions, Luis Horacio Solis

Open Access Theses & Dissertations

Tissue engineering (TE) is a multidisciplinary practice focused on developing patient-specific constructs to repair, regenerate, or replace injured tissues and organs. One biofabrication process that has gained tremendous momentum in this field is bioprinting. Most, if not all bioprinting modalities embody the same principles of heat and shear due to mechanical forces or friction as cells are forced through narrow orifices. While it is important to examine the interaction between host and implanted constructs, it is also crucial to understand the direct effects that these bioprinting technologies have on cells before embedding them into TE applications.

The purpose of this …

Design Of A Linerless Cryogenic Propellant Tank For A Small Payload Launch Vehicle, Itzel Adriana Torres

Open Access Theses & Dissertations

The need of lightweight launch vehicles that will reduce the cost and make flights more frequent into orbit has called for an increase of composite materials in the aerospace industry. Composite material’s low thermal conductivity, high resistance to fatigue, and most importantly, low-weight can greatly reduce the cost of launch operations by decreasing the overall weight of the vehicle. Weight and cost savings are critical because any amount of weight that is saved can be directly applied as an additional amount of payload capability. The tanks on space vehicles are pressurized vessels that store fuel at cryogenic temperatures and have …

Bio-Inspired Method For Close-Proximity Operations On A Near-Earth Asteroid, Rene Alberto Valenzuela Najera

Open Access Theses & Dissertations

Space maneuvers in the vicinity of small celestial bodies and achieving a soft landing over the surface of small celestial bodies are essential movements to advance the status of exploration, collection of geographical data, measurement of physical properties among other on-orbit tasks. Before a spacecraft reaches hovering position over an asteroid in order to perform orbital tasks, close-proximity operations must be done. Since the movements of the spaceships depend on the acceleration forces provided by the thrusters and external disturbances forces, the correct planning of execution of the close-up trajectories on the celestial body orbit and trajectory to land on …

Computational Methods For Creep Modeling, Ricardo Vega

Open Access Theses & Dissertations

Creep is an important phenomenon present in the power generation and aerospace industry. Creep is a mechanism that degrades the quality of a part, such as the turbines used in different industries, when elevated temperatures and loads are applied. Creep damage can cause critical failures that can cost millions of dollars and as such, prevention is important. A multitude of creep models exist to help with design and failure prevention. These models are applied using computational tools which allows the engineer to properly predict the life of a part or other material properties. In this work various creep numerical optimization …

Synthesis And Advanced Manufacturing Of Polymer Structures And Their Composites, Bethany Rose Wilburn

Open Access Theses & Dissertations

The following research work performed embodies three unique studies of polymer structures and their composites. In general, polymers are viscoelastic, insulative materials that are used for a wide variety of applications within industrial, aerospace, and biomedical fields. Polymers have been studied and optimized for any particular use by chemically synthesizing unique micro-structures, altering the physical properties through fabrication and post-processing, and utilizing 3D printing to achieve complex geometries. In the past decade, additive manufacturing (AM) has drawn extensive attention across academia, industry, and government agencies. It offers unprecedented advantages such as design freedom, rapid prototyping, and customization. In this work, …

Tram System Automation For Environmental Spectroscopy And Vegetation Monitoring, Enrique Anguiano Chavez

Open Access Theses & Dissertations

Spectroscopy is the science of studying the interactions of matter and electromagnetic radiation (EMR). In particular, field spectroscopy takes place in a natural environment with a natural source of EMR. The paper presents progress towards the development and automation of a tram cart system. The new system in development collects high resolution, hyperspectral images and data from a spectrometer. Alternatives for a sensor cover mechanism to provide cover for the sensors mounted while the system is not operating are discussed, analyzing and comparing the benefits and disadvantages. An implementation for a charging station in an environment isolated from the electric …

Additive Manufacturing Of Engineered Material Systems For Energy Applications, Luis Angel Chavez

Open Access Theses & Dissertations

Despite increasing efforts to use renewable electricity generation techniques in the last couple of decades, the world is still heavily reliant on traditional power generation techniques. This creates the need to make such systems cheaper and less pollutant through improvements to their efficiency. Increasing the efficiency and reliability of energy conversion systems, specially those based on combustion processes has been of interest for many years. However, material limitations have brought these systems to a stagnant condition.

A novel approach to help increase the efficiency of such systems is to closely monitor their operating conditions and therefore be able to increase …

Weather Prediction: Improving Accuracy Using Data Mining And Forecasting Techniques, Pedro Marquez

Open Access Theses & Dissertations

This study is focused to provide the insights of weather to understand the significance of weather changes in any parameter. Weather forecasting contributes to the social and economic welfare in many sections of the society. Weather is extremely difficult to predict because it is a complex and chaotic system. This means that small errors in the initial conditions of a forecast grow rapidly and affect predictability. Nowadays, massive real-time data is being generated by IoT devices, radars, weather stations, and satellites. The need to adopt big data analytics in IoT applications is compelling. These two technologies have already been recognized …

A Comparison Of Data-Driven And Process-Based Modeling For Nutrient Estimation In A Eutrophic Reservoir, Yohtaro Kobayashi

Open Access Theses & Dissertations

As land use around bodies of water changes, the need to model the body of water increases. Models help to educate, understand, and predict the state of water. Process-based models are commonly used in modelling bodies of water, but there are challenges with these kinds of models. They require data which can be difficult for certain communities to obtain due to logistics or cost, are computationally intensive, technically complicated, and require calibration. In contrast, a data-driven model simply connect relationships from the data, are not as computationally intensive nor technically complicated, and do not require calibration. This research compared a …

Quantifying Spatiotemporal Patterns Of Past And Future Urban Trends In El Paso, Tx And Their Impact On Electricity Consumption Using Nlcd Data And The Ca-Markov Model, Joanne Michelle Moyer

Open Access Theses & Dissertations

As cities continue to grow, their urban form continues to evolve over. Understanding this evolution allows for planners, engineers, and decision makers to plan for a sustainable community. Change analysis was conducted for El Paso, Texas county to determine the areas of growth within the past 15-years (2001-2016). The results indicate that growth has primarily occurred within the city of El Paso, in particular Districts 5 (east side), 1 (west side), and 4 (northeast), with District 5 experiencing substantial growth. Developed sub-categories medium and High intensity experienced the fastest growth, which represents single-family housing and compact/commercial areas. However, landscape metrics …

Development Of A Cold Gas Propulsion System For A 1u Cube Satellite, Norma Alicia Perea

Open Access Theses & Dissertations

In efforts to further the development test capabilities of nanosatellites on earth, NASA White Sands Test Facility (WSTF) is developing a Magnetic Levitation Table (MLT) for ground testing of nanosatellites. Testing of the table requires dedicated test articles that employ space-like systems, but those that can be used in the confines of a small lab testing area. In collaboration with WSTF, the University of Texas at El Paso (UTEP) Center for Aerospace Exploration Technology Research (cSETR) is developing an 1U cold gas propulsion cube-satellite demonstrator (CGD) to test capabilities of the levitation table. A 1U cube satellite was designed with …

Synthesis And Characterization Of Novel Lithium Gallium Phosphate (Ligap2o7) For Extreme Environment Applications, Mohan Raj Rajkumar

Open Access Theses & Dissertations

In this work, we report on the synthesis, characterization, and performance of LiGaP2O7 (LGP), a novel material and fairly new to the scientific & engineering community. LiGaP2O7 materials were was synthesized using the conventional high-temperature, solid-state ceramic reaction. Calcination was done in three steps at the temperatures of 300 °C, 500 °C, and 650 °C for 8 h each to ensure a single phase. Utilizing this, different green pellets were sintered at 800 °C for varying times of 3 h, 6 h, 12 h, and 24 h. The structure, phase, and morphology were analyzed using X-ray diffraction (XRD) and scanning …

Evaluation Of Cyclo Olefin Polymer As Sabot Material For High-Density Projectiles, Estebanne Tarango

Open Access Theses & Dissertations

Assuring the integrity of spacecraft and its occupants are a priority in the field of space exploration. Micrometeoroids and orbital debris are one of the primary threats that affect spacecraft materials due to the high kinetic energies involved with hypervelocity impacts. Improvement of projectile launching capabilities prompts the investigation of adequate materials for the manufacturing of sabots able to carry high-density projectiles without catastrophic failure. Polycarbonate (PC) has been the chosen material by the Hypervelocity Team at White Sands Test Facility for sabots on the 0.50 caliber launcher; however, there is a material constraint when the projectile becomes significantly dense …

Mechanically Activated Combustion Synthesis Of Niobium Silicide Based Composites, Reina Trevino

Open Access Theses & Dissertations

Niobium silicide-based composites are promising materials for high-temperature structural applications, such as gas turbines, but their implementation is hindered by the lack of effective processing methods. Self-propagating high-temperature synThesis (SHS) is an attractive method for fabrication of advanced materials. However, it is difficult to perform SHS of niobium silicides because the melting point of Nb is higher than the combustion temperature, which greatly inhibits Nb-Si reaction. To ignite an Nb/Si mixture and obtain Nb5Si3, the desired phase in niobium silicides, either preheating or mechanical activation of the mixture is necessary. This problem becomes even more critical in the SHS of …