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Fabrication And Characterization Of Polyvinylidene Fluoride Nanofibers For Energy Harvesting Applications, Jui Vitthal Kharade

Theses and Dissertations

Miniaturization of portable devices demand a power source that does not require recharging or replacement. Piezoelectric energy harvesters are devices that harvest mechanical energy from environment and convert it into electrical energy thus being an ideal candidate for replacing batteries in small devices. Objective of this thesis is to fabricate an energy harvester with efficient energy conversion. In this thesis, the effect of fabricating mechanisms, solvents, and composites on polyvinylidene nanofibers are analysed in order to improve the piezoelectric response of the nanofibers. These nanofibers are then used for fabricating an energy harvester. The energy harvester is implemented in a …

Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman

Theses and Dissertations

Printability is the ability to print a reproducible structure using the bioprinting technique. Constructing the relationships between printability and printing parameters of the extrusion printing process is difficult because of the presence of too many independent and inter-correlated factors. For this reason, it is necessary to identify and limit the number of significantly influential factors. In addition, Scaffold based blood vessel fabrication is a key challenge in 3D Bioprinting. As vascular smooth muscle cell (VSMCs) is a major component of blood vessels, the investigation of the behavior and orientation of VSMCs after printing is required to better understand the 3D …

Investigation Of Cell Behavior In 3d Printed Lumen Structures For Capillary Regeneration, Victoria Jade Perez

Theses and Dissertations

This thesis work successfully generated a coaxial printing setup and process to generate 3D printed tubules. A dual syringe pump mechanism was developed to print tubular structures to investigate cell behavior with a goal to generate future capillary beds. The mechanism involves the use of collagen–alginate tubules and the use of EDTA to increase the porosity of the tubule structures to study their interaction with media and incubation techniques as well as behavior and morphology. Tubules of 1.7% sodium alginate and 0.4% collagen I reacting with 3.2% CaCl2 solution proved to be more stable in both the printing process and …

Production And Characterization Of Polyurethane Fibers By Forcespinning Method And Incorporation Of Luminiscense Nanoparticles, Sunanda Kumar Saha

Theses and Dissertations

In this work, Polyurethane (PU) fine fiber nonwoven mats are generated using the Forcespinning® method. A detailed study focusing on the effect of PU concentration within solutions of N, N Dimethylformamide and the effect of relative humidity (RH) on fiber average diameter and fiber yield is presented. Solutions were prepared with 4 different concentrations, 14, 15, 16 and 17 wt% of PU. It was observed that as concentration of PU increases, average diameter shows a tendency to increase. Production of fibers with RH varying from X to X was analyzed. It was shown that higher RH is convenient for PU …

Using Single-Molecule Dna Flow-Stretching Experiments To See The Effects Of Temperature And Viscosity, Fatema Tuz Zohra

Theses and Dissertations

Deoxyribonucleic acid (DNA) is a highly charged long and semi-flexible polymer of which length is much longer than cell dimensions at least by 1,000-folds. A long linear DNA turns into a crumpled structure to fit into a tiny cell volume by the process known as DNA compaction. In nature, DNA fits into the volume of the cell using DNA compaction by packaging genome material. Various types of protein are involved in DNA compaction. To experiment with various proteins as DNA compaction agents, DNA needs to be stretched out. In our thesis, the effect of temperature and buffer viscosity on DNA …

Comparison Of Two Advanced Oxidation Processes For Their Production Of Hydroxyl Radicals And Evaluation Of A Uv/Ozone Aop At Varying Uv Fluence For Treating Diclofenac, Alexandra Cass

Master's Theses

This study explores the efficacy of two advanced oxidation processes for generation of hydroxyl radicals to promote degradation of emerging contaminants. Drought and water shortage have become pressing issues caused by our world’s changing climate. Water reclamation and reuse are increasingly important options for relieving this water stress. Water reuse runs the risk of reintroducing recalcitrant compounds that can accumulate in our bodies and environment. Advanced treatment methods that degrade these compounds are vital to protect our health and the health of the environment while providing necessary water resources. Advanced oxidation processes (AOPs) have shown great promise for removing recalcitrant …

Bilateral Ground Reaction Force Jumping Asymmetry And Performance, Keith Painter

Electronic Theses and Dissertations

The prevalence of asymmetry in performance research has increased in recent years with mixed results. Much of the performance research has focused on unilateral jumping activities attempting to show relationships to other performance variables. However, bilateral ground reaction forces (bGRF) from jumps are more frequently assessed in athlete monitoring programs and the asymmetry from those jumps could be a simple addition to data already being collected. Research into bGRF asymmetries is lacking and no studies have addressed longitudinal changes. Additionally, research into the relationship of asymmetries to performance have infrequently used athletes. For these reasons, this dissertation will focus on …

Biofiltration Application At Ethanol Plants: Analysis Of Aqueous Streams And Treatment Of Vocs, Katie Marie Mowat

Department of Environmental Engineering: Theses and Other Student Research

The United States used 14.5 billion gallons of the biofuel ethanol in 2019 produced primarily (82%) in dry-mill corn ethanol plants. These plants produce volatile organic compounds (VOCs) — some of which are hazardous air pollutants (HAPs) — during production. Traditional treatment methods for gaseous emissions use a large quantity of water or natural gas. Thus, a bio-trickling filter (BTF) is considered an innovative alternative treatment method. A lab-scale BTF was used in this study to look at the effect of ethanol concentration and temperature on the treatment of a HAPs mixture. Gaseous and aqueous testing were performed on the …

Development Of Quantitative Molecular Photoacoustic Imaging For Noninvasive Cancer Diagnostics, Cayla Zandbergen

Dissertations and Theses (Open Access)

Traditional diagnostic imaging provides clinicians with anatomical information that guides both diagnosis and treatment planning; however, once a tumor has progressed enough to be visible, it has often reached an advanced stage. Molecular imaging techniques allow for real-time visualization of chemical and biological processes via imaging of specific biomarkers, which can facilitate detection of malignancies before they become visible. One biomarker of interest is blood oxygen saturation (SO₂) due to its correlation with hypoxia, which is associated with increased tumor malignancy; some studies have also established SO₂ as an independent biomarker of disease progression. Additionally, because cancerous …

Effect Of Obesity On Walking To Running And Running To Walking Transitions, Salvador Baruch Alcorta Bautista

Theses and Dissertations

This work investigates human Walking to Running transition (WRT) and Running to Walking transition (RWT). The focus is to be able to identify the correct WRT and RWT phase jumps. This investigation uses experimental data from the VICON Motion Analysis System (MAS) and of the treadmill WRT and RWT trials. The musculoskeletal model consists of pelvis, femur, tibia, and foot. This investigation uses as reference the work reported in the literature by Diedricj and Warren.. For the calculations in this investigation Excel and Matlab are used to filter the data and calculate the relative phase jumps. This work reports the …

Determination Of The Optimal Parameters For Self-Healing Efficiency Of Encapsulated Bacteria In Concrete Simulated Subtropical Climate, Momen R. Mousa, Marwa Hassan, Gabriel Andres Arce Amador, Ricardo Hungria, Andrea Gavilanes, Omar Kamal

Publications

Concrete is a remarkable construction material. However, its low tensile strength makes it prone to cracking, which negatively affects its durability. To address this issue, bacterial concrete has been implemented as a self-healing alternative due to its capability to seal microcracks through microbial-induced calcium carbonate precipitation (MICCP). In this study, a bacterial strain (i.e, Bacillus Pseudiformus) was encapsulated through three different methods: encapsulation through hydrogel beads, vacuum impregnation on lightweight aggregates, and attachment to cellulose nanocrystals. Furthermore, three precursor types were used, magnesium acetate, calcium lactate, and sodium lactate were implemented. Compressive strength tests and flexural strength tests were performed …

Fast Magnetic Resonance Image Reconstruction With Deep Learning Using An Efficientnet Encoder, Tahsin Rahman

Open Access Theses & Dissertations

This thesis aims to develop an efficient, deep network based method for Magnetic Resonance Imaging (MRI) acceleration through undersampled MR image reconstruction. Deep Neural Networks, particularly Deep Convolutional Networks, have been demonstrated to be highly effective in a wide variety of computer vision tasks, including MRI reconstruction. However, modern highly efficient encoder structures, such as the EfficientNet can potentially reduce reconstruction times further while improving reconstruction quality. To that end, we have developed a multi-channel U-Net MRI reconstruction network which uses an EfficientNet encoder and a custom asymmetric. The network was trained and tested using 5x undersampled multi-channel brain MR …

Hardware For Quantized Mixed-Precision Deep Neural Networks, Andres Rios

Open Access Theses & Dissertations

Recently, there has been a push to perform deep learning (DL) computations on the edge rather than the cloud due to latency, network connectivity, energy consumption, and privacy issues. However, state-of-the-art deep neural networks (DNNs) require vast amounts of computational power, data, and energyâ??resources that are limited on edge devices. This limitation has brought the need to design domain-specific architectures (DSAs) that implement DL-specific hardware optimizations. Traditionally DNNs have run on 32-bit floating-point numbers; however, a body of research has shown that DNNs are surprisingly robust and do not require all 32 bits. Instead, using quantization, networks can run on …

Development Of A Laser Solder Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Prototyping In Embedded Sensing Applications, Emerson Roland Armendariz

Open Access Theses & Dissertations

Industrial and rapid prototyping (RP) trends toward miniaturization of electronic devices containing temperature sensitive electronics and surrounding materials are calling for highly controllable, selective laser soldering technologies. Laser soldering is a non-contact technique that eliminates the risk of marring or damaging sensitive components by precisely focusing a laser beam on a solder filler alloy, leading to a fast and non-destructive electrical joint. Using the benefits of accurate and controlled heat delivery via inexpensive low power laser diodes (LPDL's) in conjunction with ever-increasing additive manufacturing capability in producing complex internal features and geometries, development and testing of a laser application system …

Evaluation Of Electrodialysis Desalination Performance Of Novel And Conventional Ion Exchange Membranes, Ahm Golam Hyder

Open Access Theses & Dissertations

It was revealed from relevant recent literature that the electrodialysis (ED) desalination performance of commercial and laboratory-made ion exchange membranes (IEMs) had been studied previously but not in a systematic way so that the planners, designers, and engineers can evaluate a trade-off in selecting the suitable IEMs and optimum ED experimental conditions for their desired outcomes such as high ion selectivity, high salinity removal, high water recovery, low energy consumption, or low water transport. Furthermore, the existing conventional and laboratory-made IEMs reported previously showed various technical and economical limitations with respect to permeability, permselectivity, ion selectivity, electrical resistance, stability (mechanical, …

Methods Development, Design Analysis, And Testing Of Novel Centrifugal Devices For Mammalian Cell Culture Harvest, W. Aaron Dryden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thermo Fisher Scientific is developing a centrifugal device to be used in the biopharmaceutical industry. The novel technology was used to remove cells from cell cultures, which produce drugs and medical treatments. The harvest process of removing cells is the first step towards product purification and is an important unit operation for ensuring high product yield. Since the device is a novel technology, methods to test and evaluate the performance of the centrifuge needed to be developed.

Successful testing methods were developed in this work and were implemented on over 30 different centrifuge designs. Amongst these many designs, different operating …

Investigating The Habits Of Mind Of Practicing Engineers, Theresa K. Green

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One goal of undergraduate engineering education is to prepare students with the knowledge, skills, and decision-making strategies that are necessary for success in engineering practice. One proposed method to teach students these skills is to incorporate habits of mind into K-12 and undergraduate curricula. Habits of mind are the intelligent, social behaviors that engineers should aspire to have when solving problems, engaging with others, and dealing with uncertainty. Previous literature has suggested that incorporating ideas about habits of mind in educational curricula can teach students the disciplinary skills, technical knowledge, and social values that would help prepare them to enter …

Evaluation Of Bioretention Performance In Northern Utah As A Function Of Media, Vegetation, And Loading, Trixie Rife

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pollutants found in stormwater runoff are a growing environmental concern. The EPA has identified bioretention (BR) systems as a best management practice for the control of pollutants in stormwater runoff. BR systems reduce pollutant loads discharged to surface water bodies and to lower pollutant concentrations of water infiltrating into underlying groundwater. However, knowledge of the performance of BR systems in semi-arid Western climates is lacking. This study was conducted at three field sites in Northern Utah to evaluate the effectiveness of various natural and engineered media and various plant species on pollutant removal subjected to a range of pollutant loadings …

Structure-Property Relationship In High Strength- High Ductility Combination Austenitic Stainless Steels, Chengyang Hu

Open Access Theses & Dissertations

Austenitic stainless steels are widely used in our daily life, but their mechanical strength is low. In order to improve their yield strength via grain refinement, an investigation was carried out involving phase reversion annealing concept comprising of severe cold roll reduction followed by annealing at different temperatures for short durations. During annealing reversion of deformation-induced martensite to austenite occurred by shear mechanism, leading to fine-grained structure and high strength-high ductility combination.Nanoscale deformation studies suggested that the deformation mechanism of nanograined structure was different from the coarse-grained counterpart. Post-mortem electron microscopy of plastic zone surrounding the indent indicated that the …

Toward An Understanding Of Fundamental Mechanisms In Transitional And Turbulence Flow Control, Ethan A. Davis

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Turbulence is an emergent phenomenon found throughout nature and engineering, alike. It plays a vital role in the aquatic locomotion of organisms, scalar mixing, fluid transport, shipping and transportation, and even the flow of biological fluids in the human body. Therefore, it is of utmost importance in both a practical and engineering sense to better understand turbulence with the goal of better controlling it. This dissertation focuses broadly on better understanding the underlying mechanisms behind wall-bounded turbulent flows, with an emphasis on exploiting those mechanisms for turbulence flow control.

We developed a numerical simulation to study the effect of slip …

Effect Of Ultrasound Pressure On The Distribution Of Bovine Serum Albumin Delivered By Focused Ultrasound-Mediated Blood-Brain Barrier Opening In Cleared Mouse Brains, Yajie Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Most common diagnosis and therapeutic methods have low effectiveness when used on brain diseases. The key obstacle is that the blood-brain barrier (BBB) prevents most drugs from entering the brain. Some strategies have been developed to improve the efficiency of drug delivery crossing BBB. Among all these strategies, focused ultrasound-mediated BBB opening (FUS-BBB Opening) stands out since it is noninvasive and can be located to the target area. Detailed studies are required on the distribution of drugs delivered by FUS-BBB opening and the effects of FUS parameters on the distribution. This thesis proposes a pipeline involving tissue clearing and lightsheet …

Methane Emission Treatment And Potential Upcycling Using Methylomicrobium Alcaliphilum, Jace Parkinson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Anthropogenic methane emissions are harmful to the environment and can be difficult to treat. Use of M. alcaliphilum for bioremediation of methane looks to be one of the most promising methods of reducing the negative environmental impacts of methane emissions while simultaneously providing an economic incentive. Successful bioreactor design for M. alcaliphilum based methane treatment requires biokinetic constants and microbial growth information. Methods were established for determining biokinetic constants, including growth rate, biomass yield, specific methane consumption rate, and a correlation between methane oxidation and carbon dioxide production for M. alcaliphilum. Values determined for these constants were used to …

In Vitro Osteogenic Performance Of Two Novel Strontium And Zinc-Containing Glass Polyalkenoate Cements, Daniella Marx, Alireza Rahimnejad Yazdi, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass polyalkenoate cements (GPCs) are under investigation as potential bone adhesives, as they may provide an alternative to polymethylmethacrylate-based cements. GPCs containing strontium (Sr) and zinc (Zn) in place of aluminum (Al) are of particular interest because these ions are known stimulators of osteoprogenitor differentiation. GPCs have been manufactured from a novel bioactive glass (SiO2:0.48, ZnO:0.36, CaO:0.12, SrO:0.04) in the past, but, while such materials have been assessed for their influence on viability, their influence on osteogenic function has not been investigated until now. For this study, two GPCs were formulated from the same glass precursor evaluated in previous studies. …

Biotransformation Of Trace Organic Compounds Via Microbial Ammonia Oxidation In Biofiltration Systems For Water Reuse, Nicholas Babcock

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of ozone-biofiltration (BAF) for water reuse has recently been viewed as an attractive option due its low cost and ability to achieve high quality effluent. However, one challenge that is particularly problematic for ozone-biofiltration is the occurrence of trace organic compounds (TOrCs), such as pharmaceuticals and personal care products, in domestic wastewater, primarily due to their uncertain public health impacts. These TOrCs might be degraded by three ammonia oxidizing microorganisms (AOMs), including ammonia oxidizing bacteria (AOBs), ammonia oxidizing archaea (AOAs), and Comammox that have been found in biofiltration systems. Cometabolism, the fortuitous biodegradation of compounds by enzymes used …

Analysis Of Microscopic Objects Using Computer Vision Methods, Yuan Dao

UNLV Theses, Dissertations, Professional Papers, and Capstones

As an essential and powerful tool to observe living organisms, three-dimensional fluorescence microscopy is widely used in biological research and diagnosis. The 4D fluorescence microscopy data can be obtained using time-lapsed videos of 3D images. To analyze and extract useful information from the increasingly large and complex biological image dataset, efficient and effective computational tools are in need but still lagging behind. In analyzing biological data, two major challenges are faced. First, time-lapsed fluorescence microscopic images typically have a low SNR. Second, biological objects often change their morphology and internal structure frequently. As such, conventional image processing methods may not …

Towards Laparoscopic Visual Ai: Development Of A Visual Guidance System For Laparoscopic Surgical Palpation, Kerwin G. Caballas, Harold Jay M. Bolingot, Nathaniel Joseph C. Libatique, Gregory L. Tangonan

Electronics, Computer, and Communications Engineering Faculty Publications

Currently, there are numerous obstacles to performing palpation during laparoscopic surgery. The laparoscopic interface does not allow access into a patient's body anything other than the tools that are inserted through the trocars. Palpation is usually done with the surgeon's hands to detect lumps and certain anomalies underneath the skin, muscle, or tissues. It can be useful technique for augmenting surgical decision-making during laparoscopic surgery, especially when discerning operations involving cancerous tumors. Previous research demonstrated the use of tactile sensors and mechanical sensors placed at the end-effectors for palpating laparoscopically. In this study, a visual guidance system is proposed for …

Quantitative Analysis Of The Membrane Affinity Of Local Anesthetics Using A Model Cell Membrane., Wanjae Choi, Hyunil Ryu, Ahmed Fuwad, Seulmini Goh, Chaoge Zhou, Jiwook Shim, Masahiro Takagi, Soonjo Kwon, Sun Min Kim, Tae-Joon Jeon

Henry M. Rowan College of Engineering Departmental Research

Local anesthesia is a drug that penetrates the nerve cell membrane and binds to the voltage gate sodium channel, inhibiting the membrane potential and neurotransmission. It is mainly used in clinical uses to address the pain of surgical procedures in the local area. Local anesthetics (LAs), however, can be incorporated into the membrane, reducing the thermal stability of the membrane as well as altering membrane properties such as fluidity, permeability, and lipid packing order. The effects of LAs on the membrane are not yet fully understood, despite a number of previous studies. In particular, it is necessary to analyze which …

Dual-Axis Acousto-Optic/Electro-Optic Deflectors In Lithium Niobate For Full-Parallax Holographic Video Displays, Mitchell Robert Adams

Theses and Dissertations

A major limitation of acousto-optic (AO) leaky-mode modulator based holographic displays is their inability to present full-parallax. We propose that full-parallax capabilities can be bestowed on these displays by integrating an electro-optic (EO) phased array into the architecture. We validated this concept by rendering computational models and by fabricating and testing a basic two-axis AO/EO deflector prototype in lithium niobate. This was, to our knowledge, the first instantiation of an integrated, hybrid AO/EO deflector. The prototype had a 6° deflection range along the AO-axis, and a 3° deflection range along the EO-axis. A series of models provide us with a …

Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Harris, Martin Zwick

Complex Systems Faculty Publications and Presentations

Reconstructability Analysis (RA) and Bayesian Networks (BN) are both probabilistic graphical modeling methodologies used in machine learning and artificial intelligence. There are RA models that are statistically equivalent to BN models and there are also models unique to RA and models unique to BN. The primary goal of this paper is to unify these two methodologies via a lattice of structures that offers an expanded set of models to represent complex systems more accurately or more simply. The conceptualization of this lattice also offers a framework for additional innovations beyond what is presented here. Specifically, this paper integrates RA and …

Efficient Polyhydroxyalkanoate Production By Rhodopseudomonas Palustris From Lignocellulosic Biomass, Brandi Brown

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Polyhydroxyalkanoates (PHAs) are biopolymers produced by bacteria with the potential to replace conventional plastics. However, the relatively high production costs of PHAs are keeping them from market acceptance, with approximately half of the production costs derived from the feedstock. Thus, engineering a microbe for PHA production from cheaper and renewable carbon sources is necessary to promote the valorization of PHAs. Lignocellulosic biomass is considered to be one of the most economic carbon sources in the world, and is thus an attractive candidate for cheaper production of bioplastics. Rhodopseudomonas palustris CGA009 is a metabolically robust bacterium capable of catabolizing lignin breakdown …