Digital Commons Network^™

Exploration Of Antimicrobial And Cell Proliferation Properties Of Nanofibers Incorporating Nopal (O. Cochenillifera) Extract, Cristobal Rodriguez

Theses and Dissertations

This study focused on the fabrication of Forcespinning® nanofibers composed of Opuntia cochenillifera, ‘nopal’, mucilage (N) extract, chitosan (CH), and pullulan (PL) (N/CH/PL) were developed with an optimum fiber average diameter of 406±127 nm, and studied for their ability to sustain adhesion and proliferation of mouse embryonic fibroblast (NIH 3T3) cells. After a 6-day incubation period, N/CH/PL nanofibers displayed robust cell proliferation, while also exhibiting inhibitory properties through an N extract dip-coating process against gram-negative bacteria Escherichia coli in a 24 h bacterial growth study. A demonstration of integrated natural bioactive compounds with combined biodegradable polymers, provide an enhanced …

Peptoid-Functionalized Gold Nanoparticles For Zika Virus Envelope Protein Detection, Meagan Olsen

Chemical Engineering Undergraduate Honors Theses

Detection and identification of viral pathogens is essential in providing effective and rapid medical treatment. Well-established detection methods can be expensive, slow, and sometimes unable to provide the needed sensitivity and specificity. The Zika virus is one clinically relevant pathogen that cannot be easily identified due to cross-reactivity with other viruses from the same family. Electrochemical sensors enhanced with peptoid-functionalized gold nanoparticles (AuNPs) are an alternative to traditional techniques that offers rapid, accurate, label-free pathogen detection for point-of-care diagnostics. To this end, a peptoid capable of binding to the Zika virus envelope protein was developed and its binding affinity for …

Promotion Of Human Schwann Cell Proliferation Using Heparin/Collagen Coated Nerve Conduits, John Magness

Chemical Engineering Undergraduate Honors Theses

Often in the aftermath of an injury or surgery, the sense of touch and muscle control is lost in the affected area as nerves are damaged or severed and fail to grow back completely. The regeneration of the nerve cells can be promoted by treating the nerves with nerve conduits. Nerve conduits are hollow cylinders of bio-compatible materials that can be surgically implanted to the disconnected nerve to promote and direct the growth of nerves. The objectives of this research are to investigate the ability of nerve conduits treated with layer-by-layer coatings to promote the growth of Schwann cells, to …

Development Of An Integrated Salt Cartridge-Reverse Electrodialysis (Red) Device To Increase Electrolyte Concentrations Of Human Blood Flow To Power Biomedical Devices, Caroline Campbell

Chemical Engineering Undergraduate Honors Theses

Emerging technologies in nanotechnology and biomedical sciences have led to an increase in biomedical implantable devices including cardiac pacemakers, artificial organs, drug pumps, and sensors. These devices require continuous stable and reliable power to operate, which creates the demand for the need to find a safe, reliable, and stable power source. A promising avenue for a power source for these devices is a miniaturized reverse electrodialysis (RED) biopower cell design that utilizes the salinity differences between bloodstreams that flow inside the human body. Initial results of the RED system demonstrate that higher gradient salinity differences between streams lead to a …

Garver Industrial Design Project: Designing A Full-Scale Reverse Osmosis Water Treatment Facility For The City Of Lawton, Oklahoma, Kayliana Warden, Marlando Collins, Sandrina Depaz, Reid Eakin, Reed Leasure, Vera Rodriguez

Chemical Engineering Undergraduate Honors Theses

A groundwater treatment facility was designed for Lawton, Oklahoma to address potential water scarcity due to drought conditions in southwest Oklahoma. The facility will produce five million gallons per day (MGD) of treated water. The plant will have the capacity of treating 4,085 gallons per minute of influent water at an 86% recovery. The water to be treated will come from the Arbuckle-Timbered Hills Aquifer. Studies have been conducted around the aquifer to identify the best well site locations.

A centralized treatment facility using reverse osmosis filtration as the main treatment technology has been designed. To prevent reverse osmosis membrane …

Analyzing The Effects Of E-Hook Peptides On Kinesin-1, Ashton Ward Murrah, Baylee Hope Howard

Honors Theses

Cancer is the second leading cause of death in the United States. Cancerous growth is a result of oncogenes, or mutated genes that increase the rate of cell division in an uncontrolled manner. Cell division, which consists of mitosis and cytokinesis phases, is dependent upon the active movement of kinesin motor proteins along microtubules to rearrange the cytoskeleton for equitable distribution of genetic material to daughter cells. As kinesins are vital to this process, if we could prevent kinesin from binding to the microtubules, cell division would cease.

The goal of this study is to develop a method to prevent …

Introduction Of New Value Stream Through Vermicomposting Process, James Spalding, Joseph Harris

Honors Theses

The purpose of our project is to analyze whether a waste byproduct can be monetized into a viable profit stream for Wonderbird Spirits. Spent grain, a waste byproduct created by the distillation process, is currently the company’s biggest source of material waste. The CME project team designed and built a trommel to aid liquid-solid separation of the spent grain so that the solid portion can be repurposed as feedstock for a vermicomposting setup. We also suggest vermicomposting setup for the distillery based on the needs and capabilities of Wonderbird Spirits. We present financial analyses detailing the cost of creating the …

Molecular Mechanisms Of Oxidative Stress On Molecular Motors, Addison Caspari-Linhardt

Honors Theses

Astronauts encounter many forms of ionizing radiation during space travel. Ionizing radiation has been seen to cause cancer, cataracts, radiation sickness, tissue damage, hereditary effects, and damage to the central nervous system. Ionizing radiation can damage DNA molecules through oxidation, as well as other vital proteins like molecular motors. Kinesin-1 is a molecular motor protein that essential to intracellular transport. Microtubules serve as the “roadway” for kinesin transport, where kinesin converts chemical energy from ATP hydrolysis into mechanochemical “steps” to move along the microtubules. Optical trapping has been used in previous research to measure single kinesin motor properties. We have …

3d Printing Of High Viscosity Fluids And Its Application In 3d Printing Of Prosthetic Teeth., Abhilash Aditya

Open Access Theses & Dissertations

The advancement in technology has brought forward non-conventional manufacturing methods that are efficient and advantageous for specific applications. 3D printing is one such outcome, whose applications stretch from biomedical applications to daily products. 3D printing is a rapidly growing technology, and innovative research developments have proven versatility in creating physical objects. Simplification and constant improvement in Fused Deposition Modeling (FDM) operation result from decades of research. However, 3D printing is material-specific and contributes to shortcomings in the technology. The build-material dictates the extrusion parameters, including the material discharge rate and head speed for a continuous flow. Customization being the prime …

Raw Depth Image Enhancement Using A Neural Network, Xuan Xie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term image is often used to denote a data format that records information about a scene’s color. This dissertation object focuses on a similar format for recording distance information about a scene, “depth images”. Depth images have been used extensively in consumer-level applications, such as Apple’s Face ID, based on depth images for face recognition.

However, depth images suffer from low precision and high errors, and some post-processing techniques need to be utilized to improve their quality. Deep learning, or neural networks, are frameworks that use a series of hierarchically arranged nonlinear networks to process input data. Although each …

Engineering Cardiac Tissues With Three-Dimensional Bioprinting For Biomedical Applications, Matthew Alonzo

Open Access Theses & Dissertations

The role of a biomedical engineer is to solve unmet health-related needs that face society. For the past couple of decades, heart disease (HD) has remained the leading cause of mortality and morbidity worldwide. The disease is characterized by various pathologies that affect the heart. Indeed, malfunction of one of the bodyâ??s most vital organs is bound to manifest poor health and even death in patients. Despite advances in medicine and technology, heart disease continues to be prevalent and diminishes the quality of life for many around the world. Certainly, there exists a need for developing new tools to better …

Investigation Of Bio-Inspired Pin Geometries For Heat Transfer Applications, Anish Prasad

Doctoral Dissertations and Master's Theses

Array of circular cylindrical pins or tubes are one of the most widely used type of convection cooling systems, profoundly used in the internal cooling of gas turbine blades. They promote heat transfer due to flow acceleration, secondary flows and wake shedding, at the expense of large pressure loss and unsteadiness in the flow. The need to reduce pressure loss and maintain the heat transfer rates are a much needed requirement for a variety of industries to improve the cooling efficiency. One such prominent line of research is conducted on optimizing the design of the circular cylindrical pins to increase …

Remote Performance Modulation Of Ultrafiltration Membranes By Magnetically And Thermally Responsive Polymer Chains, Arijit Sengupta, Anh Vu, Xianghong Qian, Sumith R. Wickramasinghe

Chemical Engineering Faculty Publications and Presentations

Ultrafiltration membranes, that respond to an external magnetic field and local temperature have been developed. Surface-initiated activator-generated electron transfer (AGET) atom transfer radical polymerization (ATRP) has been used to graft poly(N-isopropylacrylamide) (PNIPAm) from the surface of 300 kDa regenerated cellulose membranes. The polymerization initiator was selectively attached to the entire membrane surface, only the outer membrane surface or only the inner pore surface. A superparamagnetic nanoparticle was attached to the end of the polymer chain. The DI water flux as well as the flux and rejection of bovine serum albumin were investigated in the absence and presence of a 20 …

Photothermal Response Induced By Nanocage-Coated Artificial Extracellular Matrix Promotes Neural Stem Cell Differentiation, Seunghyun Jung, Nathaniel Harris, Isabelle I. Niyonshuti, Samir V. Jenkins, Abdallah M. Hayar, Fumiya Watanabe, Azemat Jamshidi-Parsian, Jingyi Chen, Michael J. Borrelli, Robert J. Griffin

Mechanical Engineering Faculty Publications and Presentations

Strategies to increase the proportion of neural stem cells that differentiate into neurons are vital for therapy of neurodegenerative disorders. In vitro, the extracellular matrix composition and topography have been found to be important factors in stem cell differentiation. We have developed a novel artificial extracellular matrix (aECM) formed by attaching gold nanocages (AuNCs) to glass coverslips. After culturing rat neural stem cells (rNSCs) on these gold nanocage-coated surfaces (AuNC-aECMs), we observed that 44.6% of rNSCs differentiated into neurons compared to only 27.9% for cells grown on laminin-coated glass coverslips. We applied laser irradiation to the AuNC-aECMs to introduce precise …

Aloe Vera Extract-Based Composite Nanofibers For Wound Dressing Applications, Raul Barbosa, Alexa Villarreal, Cristobal Rodriguez, Heriberto De Leon, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications

Natural, biocompatible, and biodegradable composite nanofibers made of Aloe vera extract, pullulan, chitosan, and citric acid were successfully produced via Forcespinning® technology. The addition of Aloe vera extract at different weight percent loadings was investigated. The morphology, thermal properties, physical properties, and water absorption of the nanofibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The developed nanofiber membranes exhibited good water absorption capabilities, synergistic antibacterial activity against Escherichia coli, and promoted cell attachment and growth. Its porous and high surface area structure make it a potential candidate for wound dressing …

Performance Of Ultrasound-Assisted Forward Osmosis Membrane Process In Desalination Of Seawater, Bara Awwad Al-Sakaji

Theses

The objective of this study was to investigate the effect of using ultrasound on water flux through forward osmosis membrane when applied for seawater desalination. A synthetically prepared solution simulating seawater characteristics was used. Parameters considered in the investigation included membrane cross-flow velocity (0.25 and 1.0 cm/s), flow configuration (co-current versus counter-current), direction of ultrasound waves relative to the membrane side (active layer versus support layer), and type of draw solution (NaCl versus MgCl₂). Furthermore, a two-level factorial design was considered in the analysis of the results obtained from the experimental work. This study revealed that applying a …

Modulation And Long-Term Release Of Cardiac Fibroblast Secretome To Enhance Cardiac Cell Survival Under Hypoxia, Jingxuan Zhai

McKelvey School of Engineering Graduate Student Theses & Dissertations

The irreversible damage to the heart caused by myocardial infarction (MI) leads to over one million deaths in the United States every year. There are several approaches to treat MI, such as angioplasty, redirected blood flow, and electrical medical devices, but they cannot promote new cardiac tissue generation, thus leading to potential high risk of re-surgeries. To overcome this limitation, stem cell therapy is regarded as a promising method. However, the implantation of stem cells has ethical and safe concern and the efficiency is limited due to low cell engraftment. Moreover, the effect of stem cell is predominantly attributed to …

Plasma Aerodynamics: Experimental Quantification Of The Lift Force Generated On An Airfoil Using Plasma Actuation To Estimate Power Requirements In Small Uav Applications, Getachew Ashenafi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research addressed the amount of electric power required to induce specific changes in lift force using a NACA 2127 airfoil with a chord length of ~28 mm, connected to a micro load cell, in a wind tunnel of 103 square centimeter cross-section. A DBD plasma actuator supplied by a ZVS driven high voltage pulsed DC circuit, operating at a frequency of 17.4 kHz, was utilized for voltages of up to 5000 V. Two configurations of electrode gapping were compared to determine the efficient use of power. The configuration with a gap of ~1 mm between the upstream and downstream …

Healthy Aging In Place: An Integrated Smart Home Using Alexa-Compatible Technology, Tyler Kryst

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to address current healthcare concerns among the aging population. Around the globe, the average life expectancy is projected to continue increasing resulting in a higher prevalence of age-related disease. With the ever-increasing capabilities of modern technology, it is necessary to apply this technology to increase the health and safety of older adults. This work had three objectives. The first objective was the establishment of an integrated smart home aimed at creating a healthy aging-in-place environment through the use of Alexa. The second objective was the development and integration of a completely custom health device …

A Hyperelastic Porous Media Framework For Ionic Polymer-Metal Composites And Characterization Of Transduction Phenomena Via Dimensional Analysis And Nonlinear Regression, Zakai J. Olsen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ionic polymer-metal composites (IPMC) are smart materials that exhibit large deformation in response to small applied voltages, and conversely generate detectable electrical signals in response to mechanical deformations. The study of IPMC materials is a rich field of research, and an interesting intersection of material science, electrochemistry, continuum mechanics, and thermodynamics. Due to their electromechanical and mechanoelectrical transduction capabilities, IPMCs find many applications in robotics, soft robotics, artificial muscles, and biomimetics. This study aims to investigate the dominating physical phenomena that underly the actuation and sensing behavior of IPMC materials. This analysis is made possible by developing a new, hyperelastic …

Investigation Of Bench-Scale Packed Bioreactor For Perchlorate Reduction In The Presence Of Co-Contaminants And High Salinity, Julia Ribeiro Rabello

UNLV Theses, Dissertations, Professional Papers, and Capstones

Perchlorate (ClO4-), commonly found as a salt, is naturally occurring in nature and is found in natural nitrate deposits (such as the Chilean nitrate). Perchlorate anion is considered an inhibitor of iodine by the thyroid gland, reducing the production of thyroid hormones. The latest action by the USEPA was to not determine a national drinking water standard for perchlorate. However, the states still have their own regulations on perchlorate concentration in drinking water. Contaminated sites with high concentrations of perchlorate (ppm levels) are associated with historic perchlorate manufacture and use, while those with low concentrations (ppb levels) are found in …

Patient-Specific Finite Element Analysis For Mandibular Fracture Fixation, Ethan Snyder

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis proposes an approach for Finite Element Analysis (FEA) of mandibular fracture fixation. Using a Computerized Tomography (CT) scan of mandible obtained from a specific person, the material characteristics, density and modulus of elasticity, were determined from a set of discrete points within the mandible that are 1mm spaced based on the Hounsfield Units of these points. The mandible geometry was sectioned to simulate a fracture. Muscle and mastication forces were added to replicate post-surgery loading. Using a standard linear miniplate, this material model was compared with two commonly used mandibular cortical shell bone models: isotropic and orthotropic. A …

Degradation Of Antibiotics In Aqueous Phase Using Pms Catalytic Decomposition With Zero-Valent Iron Nanoparticles Immobilized In Sba-15, Ahdee Bluma Zeidman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zero-valent iron nanoparticles (nZVI) have been studied as an option for soil remediation and water treatment for many years. The capability of nZVI to produce oxidation/reduction processes, depending on the reaction conditions, has attracted great interest with their major drawback being reactivity loss through agglomeration. The loss in nZVI surface area has been reported to be prevented through immobilization onto a porous media (e.g., SBA-15, MCM-41, or zeolites). In this work, a mesoporous silica structure (SBA-15) is used as an nZVI supporting material to enhance its reactivity and promote peroxymonosulfate (PMS) catalytic decomposition for the degradation of antibiotics in aqueous …

Bioink Optimization And Effects Of Microgravity On 3d Bioprinted Cell Laden Constructs, Likitha Somasekhar

Theses and Dissertations

Bioengineered 3D tissue constructs have gained attention as in vitro tools for the study of cell-cell and cell-matrix interactions and are being explored for potential use as experimental models for mimicking human tissues. One of the main problems in tissue engineering is the necessity to vascularize complex engineered tissues and sacrificial printing has been recognized as a possible solution to vascularization of the bioprinted tissues. Research studies have demonstrated that exposure to microgravity in space induces adaptive alterations in vascular structure and function. Changes in the morphology and gene expression is observed when endothelial cells are exposed to microgravity and …

A Comparative Study To Assess The Osteogenic Potential Of Competing Bioceramics For Bone Tissue Engineering, Nashaita Patrawalla

Theses and Dissertations

Biomimetic composite scaffolds comprising of bioactive ceramic-based materials incorporated within a polymeric framework have shown considerable promise for use in bone tissue engineering (BTE) applications. Although bioceramics have shown immense promise for use in BTE, few studies have performed a head-to-head comparison of the osteogenic properties of the most promising bioceramic materials. The goal of this study was to compare three different bioceramics – Bioglass 45S5 (BG), Laponite XLG (LAP), and β-Tricalcium Phosphate (TCP) – on the physical properties (i.e., swelling, stability, compressive modulus, bone bioactivity) of methacrylated collagen (CMA) hydrogels and osteogenic differentiation of human MSCs (hMSCs) encapsulated within …

The Effect Of Simulated Mangrove Forest Width On Shoreline Stabilization At Multiple Tidal Water Levels, James Edward Austin

Theses and Dissertations

Red mangrove (Rhizophora mangle) forests protect hundreds of miles of Florida’s shorelines from erosion and wave damage associated with severe storms and daily wave action. Shorelines are often protected from erosion with man-made structures such as seawalls, revetments, and breakwaters. However, these man-made structures disrupt natural ecosystems and cause scour and erosion in surrounding areas. The presence of mangroves not only prevents erosion but shelters marine life and filters water, promoting ecological health. Mangroves are now being implemented for wave energy reduction and shoreline stabilization, but there is little quantitative data about the precise sediment transport induced or prevented by …

Centrifugally-Spun Ceramic/Carbon Composite Fibers And Their Use As Anode Materials In Li-Ion Batteries, Gabriel Gonzalez

Theses and Dissertations

The work in this thesis focuses in the study of Centrifugally Spun Short Fiber Composites and their Implementation as Alternate Anode Material in Li-Ion Batteries. Due to their high theoretical capacity, abundance, and environmental friendliness, metal oxides have been widely studied as alternate anode materials for lithium ion batteries (LIBs). In this research work, the processing of SnO2 and SnO2/TiO2 ceramic short fibers as well as flexible and porous metal oxide carbon fibers (FPMOCFs) by centrifugal spinning followed by an optimized coating technique is reported. In addition, the electrochemical performance of the composites was also investigated and is provided.

Fabrication Of Forcespinning® Nanofibers Incorporating Nopal Extract, Cristobal Rodriguez, Victoria Padilla, Karen Lozano, J. Andrew Mcdonald, Luis Materon, Alejandra Chapa, Fariha Ahmad, Carlos Trevino De Leon, Robert Gilkerson

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

In this study, nanofibers composed of Opuntia cochenillifera nopal mucilage (N) extract combined with chitosan (CH) and pullulan (PL) (N/CH/PL) were produced via Forcespinning®. The developed nonwoven composite membranes are comprised of long, continuous, and homogenous fibers with fiber average diameter varying between 251±77 nm and 406±127 nm depending on the concentration of N. After crosslinking, the developed membranes were highly stable in water. The water absorption capacity of the N/CH/PL composite nanofiber membranes was shown to be 65% higher when compared to the CH/PL nanofiber membranes. Nopal dipcoated membranes show inhibition of gram-negative Escherichia coli, indicating antibacterial properties. These …

In Vivo Analysis Of A Proprietary Glass-Based Adhesive For Sternal Fixation And Stabilization Using Rabbit And Sheep Models, Cina Mehrvar, Emily Deignan, Mark Hurtig, Gideon Cohen, Paul Zalzal, Oleg Safir, Adel Alhalawani, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Wire cerclage remains the standard method of care for sternal fixation, following median sternotomy, despite being beset with complications. An emerging treatment option has been to augment the wires with an adhesive. A patented ionomeric glass (mole fraction: SiO₂:0.48, ZnO:0.36, CaO:0.12, SrO:0.04) has been used to formulate GPC+, a glass polyalkenoate cement (GPC), by mixing it with poly(acrylic) acid (PAA) and de-ionized water. In a human cadaver study, this material, when applied with wire cerclage, was able to significantly reduce sternal instability. However, the material has yet to be tested in pertinent animal models. Here, after a series …

On Compressional Wave Attenuation In Muddy Marine Sediments, Charles W. Holland, Stan E. Dosso

Electrical and Computer Engineering Faculty Publications and Presentations

A method for measuring in situ compressional wave attenuation exploiting the spectral decay of reflection coefficient Bragg resonances is applied to fine-grained sediments in the New England Mud Patch. Measurements of layer-averaged attenuation in a 10.3 m mud layer yield 0.04 {0.03, 0.055} dB/m/kHz (braces indicate outer bounds); the attenuation is twice as large at a site with 3.2 m mud thickness. It is shown that both results are heavily influenced by a ∼1 m sand-mud transition interval created by geological and biological processes that mix sand (at the base of the mud) into the mud. Informed by the observations, …