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Design Of A Pretreatment And Enzymatic Saccharification Scheme Of Understory From Managed Pine Forest For A Biochemical-Refinery Platform: The Example Of The Sweetgum Tree, Angele Djioleu

Graduate Theses and Dissertations

The possibility of using sweetgum from southern pine dominated forests as a biobased refinery feedstock was investigated. First, a baseline hydrolysis scheme for sweetgum wood and bark was designed. Sweetgum wood and bark were pretreated with 0.98% (v/v) sulfuric acid at 140°C for 30, 40, 50, 60 or 70 min and at 160°C for 30, 40, 50 or 60 min. The water insoluble solid (WIS) fraction was hydrolyzed with a cellulase enzyme cocktail. Results showed that maximum xylose and glucose yields from the wood were 82 and 86%, respectively. Similarly, the respective maximum yields of xylose and glucose from the …

A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh

Graduate Theses and Dissertations

This study compares a novel simulation approach to the conventional Soil and Water Assessment Tool (SWAT) modeler's approach for targeting biofuel crop production on marginal lands. In conventional SWAT modeling approach, non-spatial definition of hydrological response units (HRUs) results in the simulation of biofuel crops on both marginal and non-marginal land. This study provides an alternative approach in which a marginal-land raster was integrated into the land use and land cover (LULC) raster in such a way that the land uses were divided into marginal and non-marginal components. This modified LULC was used for model setup which resulted in marginal …

Computational Design Of The Electrical And Mechanical Performance Of Steerable Mems Antennas, Morgan Andrew Roddy

Graduate Theses and Dissertations

This thesis describes the origins, improvements, and variations of a broadband microwave antenna that can be beam-steered by a micro-electromechanical system (MEMS). The steerable MEMS antenna of this work was comprised of a planar antenna on top of a Silicon membrane. The membrane is etched to create a gimbal hinge structure and a platform which supported the antenna and gave it one or two degrees of freedom of rotation. The antennas presented were broadband and fed by a coplanar waveguide (CPW) transmission line which traversed the hinge structure. The antenna's orientation in space was designed to be changed through electrostatic …

Capillary And Microchip Electrophoresis For The Monitoring Of Disease Causing Amyloid Proteins, Elizabeth Nancy Pryor

Graduate Theses and Dissertations

The detection of oligomers and aggregates formed by two amyloid proteins, insulin and amyloid-beta (AB), is of particular importance due to the role which these species play in Diabetes and Alzheimer's disease, respectively. However, existing techniques are limited in the ability to detect insulin and AB; oligomers due to the fact that these early aggregates are transient, present at low concentrations, and difficult to isolate. Improvements must be made to existing techniques or alternative techniques must be explored in order to identify and quantify the size of these oligomeric and aggregate species without disrupting their structure.

Capillary and microchip electrophoresis …

Colorimetric Oxygen Imaging And Quantification With Easily Accessible Optical Devices, Satya Achanta, Sanghan Park, Chang-Soo Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Optical oxygen imaging is essential in monitoring two-dimensional analysis of oxygen distribution. Two easily accessible optical devices were used for oxygen analysis to demonstrate the feasibility of an innovatively simple method. a light panel screen with light-emitting diode (LED) backlight was used as a light source to excite a luminophore film responsive to oxygen. Meso-scale fluidic sensor platform was prepared using porphyrin complex (PtOEP) as the luminophore embedded within ethyl cellulose (EC) polymer matrix. Green LED light uniformly displayed from the light panel excited the luminophore film to exhibit two-dimensional luminescence distribution corresponding to wet gaseous oxygen. a color camera …

Zheng Classification In Traditional Chinese Medicine Based On Modified Specular-Free Tongue Images, Ratchadaporn Kanawong, Tayo Obafemi-Ajayi, Jun Yu, Dong Xu, Shao Li, Ye Duan

Electrical and Computer Engineering Faculty Research & Creative Works

Traditional Chinese Medicine practitioners usually observe the color and coating of a patient's tongue to determine ZHENG (such as Cold or Hot ZHENG) and to diagnose different stomach disorders including gastritis. In our previous work, we explored new modalities for clinical characterization of ZHENG in gastritis patients via tongue image analysis using various supervised machine-learning algorithms. We proposed a system that learns from the clinical practitioner's subjective data how to classify a patients health status by extracting meaningful features from tongue images based on color-space models. In this paper, we propose an enhancement to the ZHENG classification system: a coating …

Reducing In-Stent Restenosis Through Novel Stent Flow Field Augmentation, Eoin Murphy, Fergal Boyle

Articles

In-stent restenosis (ISR), manifested as a re-narrowing of the arterial lumen post-implantation of a stent, is a detrimental limitation of stent technology. Understanding and consequently devising ways of reducing the frequency of ISR has been a continuing goal of research into improved stent designs. The biological processes that can lead to ISR have been found to be partially flow dependent with the local hemodynamics at the arterial wall of crucial importance. This paper investigates these biological processes and their instigating factors. Furthermore, the history and theory behind three stent technologies which endeavour to reduce ISR rates through stent flow field …

Quantifying The Effect Of Nanoparticles On As(V) Ecotoxicity Exemplified By Nano-Fe2o3 (Magnetic) And Nano-Al2o3, Ji Hu, Demin Wang, Brett E. Forthaus, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Nano-Fe₂O₃ (magnetic) and nano-Al₂O₃ are increasingly used in biomedical fields for cellular labeling and drug delivery, and in the industry as catalysts. However, they may also serve as carriers of toxic contaminants and negatively impact the environment and human health. in the present study, Ceriodaphnia dubia was used to assess the toxicity of these nanoparticles (NPs) with and without the presence of background arsenic(V) (As[V]). the results showed that although these NPs alone did not exhibit significant toxicity in the experimental concentration range, they could significantly enhance the toxicity of As(V). the accumulation of …

Fabrication Of Cao-Nao-Sio2/Tio2 Scaffolds For Surgical Applications, A. W. Wren, A. Coughlan, K. E. Smale, S. T. Misture, B. P. Mahon, O. M. Clarkin, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

A series of titanium (Ti) based glasses were formulated (0.62 SiO₂-0.14 Na₂O-0.24 CaO, with 0.05 mol% TiO₂ substitutions for SiO₂) to develop glass/ceramic scaffolds for bone augmentation. Glasses were initially characterised using X-ray diffraction (XRD) and particle size analysis, where the starting materials were amorphous with 4.5 μm particles. Hot stage microscopy and high temperature XRD were used to determine the sintering temperature (̃700 °C) and any crystalline phases present in this region (Na₂Ca₃Si₆O₁₆, combeite and quartz). Hardness testing revealed that the Ti-free control (ScC- …

Altered Hemodynamics, Endothelial Function, And Protein Expression Occur With Aortic Coarctation And Persist After Repair, Arjun Menon, Thomas J. Eddinger, Hongfeng Wang, David C. Wendell, Jeffrey M. Toth, John F. Ladisa

Biomedical Engineering Faculty Research and Publications

Coarctation of the aorta (CoA) is associated with substantial morbidity despite treatment. Mechanically induced structural and functional vascular changes are implicated; however, their relationship with smooth muscle (SM) phenotypic expression is not fully understood. Using a clinically representative rabbit model of CoA and correction, we quantified mechanical alterations from a 20-mmHg blood pressure (BP) gradient in the thoracic aorta and related the expression of key SM contractile and focal adhesion proteins with remodeling, relaxation, and stiffness. Systolic and mean BP were elevated for CoA rabbits compared with controls leading to remodeling, stiffening, an altered force response, and endothelial dysfunction both …

The Effect Of Cone Opsin Mutations On Retinal Structure And The Integrity Of The Photoreceptor Mosaic, Joseph Carroll, Alfredo Dubra, Jessica C. Gardner, Liliana Mizrahi-Meissonnier, Robert F. Cooper, Adam M. Dubis, Rick Nordgren, Mohamed Genead, Thomas B. Connor Jr., Kimberly E. Stepien, Dror Sharon, David M. Hunt, Eyal Banin, Alison J. Hardcastle, Anthony T. Moore, David R. Williams, Gerald Fishman, Jay Neitz, Maureen Neitz, Michel Michaelides

Biomedical Engineering Faculty Research and Publications

Purpose.

To evaluate retinal structure and photoreceptor mosaic integrity in subjects with OPN1LW and OPN1MW mutations.

Methods.

Eleven subjects were recruited, eight of whom have been previously described. Cone and rod density was measured using images of the photoreceptor mosaic obtained from an adaptive optics scanning light ophthalmoscope (AOSLO). Total retinal thickness, inner retinal thickness, and outer nuclear layer plus Henle fiber layer (ONL+HFL) thickness were measured using cross-sectional spectral-domain optical coherence tomography (SD-OCT) images. Molecular genetic analyses were performed to characterize the OPN1LW/OPN1MW gene array.

Results.

While disruptions in retinal lamination and cone mosaic structure were observed …

Novel Electron Shuttling Compounds, Ramasubramanian Neeraja

All Theses

Electron mediator's usage in remediation technologies might be an excellent alternative to increase the rate of transformation of various contaminants such as nitroamine, polyhalogenated compounds and many others. Employing electron shuttles open up different pathways for the contaminant transformation and the reaction goes to completion at a much faster rate. Anthraquinone-2,6-disulfonate (AQDS) has been known to be a model electron shuttle with good shuttling capacity followed by humic acids. But the necessity for identifying electron shuttles suitable for field applications is important. As remediation technologies will command application of the shuttles on a large scale, tracing shuttles which are cheap, …

The Effects Of Low Dose Ionizing Radiation Exposure On The Metabolic And Mechanical Properties Of Articular Cartilage, Carl Lindburg

All Theses

Radiation therapy is necessary treatment for many cancer patients due to its non-surgical, yet aggressive and efficacious properties. In fact, over 50% of patients with cancer will undergo some form of radiotherapy during the course of their treatment. While the biological response to ionizing radiation has been examined over the years and many adverse effects have been identified, the effects of radiation on mature cartilage and musculoskeletal tissues are not well understood. Bone, once thought to be a tissue relatively resistant to radiation, has recently been shown to have osteoporosis-like bone atrophy after exposure to low doses (2 Gy) of …

Study On Corrosion Activity Of Carbon Steel In Concrete Simulated Pore Solution Under Static Tensile And Compressive Stresses, Yujie Zhang

All Theses

Reinforced concrete is a structure material made up of concrete with relatively lower tensile strength containing reinforcements with higher tensile strength and better ductility, which are embedded into fresh concrete to resist tensile stress in certain regions of concrete. Steel reinforced concrete is most widely used around the world in civil engineering structures, water conservancy and highway construction due to its durability strength and reasonable cost.
However, reinforced concrete structures such as bridges and parking lots slabs inevitably experience variable loads and constant degradation from the aggressive environments, such as marine and deicing salts. Therefore, it is imperative to study …

Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson

All Theses

This work seeks to quantify the impact and effectiveness of green infrastructure practices, specifically bioretention cells and porous asphalts, for the reduction of peak flow and volume of stormwater that discharges into the headwaters of the Sand River watershed in Aiken, SC. Stormwater runoff flows and volumes were monitored in the upper Sand River watershed that includes the urban Aiken area, along with two nested subwatersheds, prior to, during, and after the construction of the bioretention cells and porous asphalt sites. Flow data from these monitoring stations were analyzed and the data suggested that there was no significant reduction in …

Preliminary Investigation Into The Design Of Thermally Responsive Forster Resonance Energy Transfer Colloids, Monte Bedford

All Theses

While nuclear imaging techniques (Magnetic Resonance Imaging, Computed Tomography, and Positron Emission Tomography) have proven effective for diagnosis and treatment of disease in the human body, fluorescence-enhanced optical imaging offers additional benefits. Fluorescent imaging provides high resolution with real-time response, persistent lifetime (hours to days), cell targeting, and transdermal penetration with minimal physical encumbrance. Malignant cells can be targeted by absorbance of exogenous fluorescent nanoprobe contrast agents. Imaging is improved by fluorescent enhancement, especially by energy transfer between attached dyes. Also for use against cancer are heat-active treatments, such as hyperthermal, photothermal, and chemothermal therapies. Helpful to these treatments is …

Study Of Cell Viability During Laser Direct Writing Of Cell-Alginate Suspension, Hemanth Gudapati

All Theses

Laser-assisted cell printing, developed based on Matrix-assisted pulsed-laser evaporation direct-write (MAPLE DW), a typical LIFT (laser-induced forward transfer) practice, has been emerging as one of the most promising biofabrication techniques. Alginate, particularly sodium alginate, is extensively used as the constituent of bioink in laser-assisted cell printing. However, thus far, studies investigating the effect of alginate gelation on cell viability in laser-assisted cell printing are lacking. The objective of this study is to investigate the effects of gelation, gelation time, sodium alginate concentration, and the effect of operating conditions such as the laser fluence on post-transfer cell viability during laser-assisted cell …

Bioswellable Amphiphilic Copolymers, David Ingram

All Theses

The suture is one of the most commonly used medical devices, consisting of a fiber, a surgical needle and the packaging in which it is stored. The fiber itself remains after implantation for a defined time and is responsible for the approximation of the wound during the healing process. The needle merely serves to aid in insertion, and preferably has a diameter larger than the diameter of the fiber .
The 1970's marked the birth of a new family of fibrous materials for the approximation of wounds: synthetic absorbable sutures. This family has the ability to provide wound support during …

Investigating The Impacts Of Conventional And Advanced Treatment Technologies On Energy Consumption At Satellite Water Reuse Plants, Jonathan Roy Bailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the ever increasing world population and the resulting increase in industrialization and agricultural practices, depletion of two of the world's most important natural resources, water and fossil fuels, is inevitable. Water reclamation and reuse is the key to protecting these natural resources. Water reclamation using smaller decentralized wastewater treatment plants, known as satellite water reuse plants (WRP), have become popular in the last decade. With stricter standards and regulations on effluent quality and requirements for a smaller land footprint (i.e. real estate area), additional treatment processes and advanced technologies are needed. This greatly increases the energy consumption of an …

Adaptive Local And Global Synchronization And Phase Control Of Inferior Olive Neurons (Ions), Srujan Kumar Chalike

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clusters of inferior olive neurons (IONs) in the olive-cerebellar system play an important role in providing synchronized motor control signals for the activation of large number of muscles. However, the dynamics of IONs are highly nonlinear and the system parameters are assumed to be unknowm. The IONs evolving from arbitrary initial conditions are not synchronized. However the application of IONs for control of BAUV's requires that IONs oscillate in unison. The objective is to design control laws such that the controlled ION tracks the trajectories of the reference ION. The two control laws are derived based on tuning functions adaptive …

Hardware-Software Co-Design, Acceleration And Prototyping Of Control Algorithms On Reconfigurable Platforms, Desta Kumsa Edosa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Differential equations play a significant role in many disciplines of science and engineering. Solving and implementing Ordinary Differential Equations (ODEs) and partial Differential Equations (PDEs) effectively are very essential as most complex dynamic systems are modeled based on these equations. High Performance Computing (HPC) methodologies are required to compute and implement complex and data intensive applications modeled by differential equations at higher speed. There are, however, some challenges and limitations in implementing dynamic system, modeled by non-linear ordinary differential equations, on digital hardware. Modeling an integrator involves data approximation which results in accuracy error if data values are not considered …

Synthesis And Characterizations Of Pyridinium Salts Including Poly(Pyridinium Salt)S And Their Applications, Tae Soo Jo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pyridinium salts, both molecular and polymeric, are an interesting class of multifunctional materials that exhibit liquid-crystalline and light-emitting properties. Moreover, their properties can be easily tuned by introducing new types of anions or by modifying their chemical structures. This dissertation describes synthesis and characterization of poly(pyridinium salt)s containing macrocounterions and fluorene moieties in their backbones, synthesis and characterization of nanocomposites of poly(pyridinium salt)s with single-walled carbon nanotubes via non-covalent interactions, and synthesis and characterizations of pyridinium salts having different aliphatic linkages and their application in organic acid sensing.

First, all of these ionic polymers were prepared by either ring-transmutation or …

Post Processing Of Optically Recognized Text Using First Order Hidden Markov Model, Spandana Malreddy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis, we report on our design and implementation of a post processing system for Optically Recognized text. The system is based on first order Hidden Markov Model (HMM). The Maximum Likelihood algorithm is used to train the system with over 150 thousand characters. The system is also tested on a file containing 5688 characters. The percentage of errors detected and corrected is 11.76% with a recall of 10.16% and precision of 100%

The Impact Of Advanced Wastewater Treatment Technologies And Wastewater Strength On The Energy Consumption Of Large Wastewater Treatment Plants, Timothy Stephen Newell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Wastewater treatment is an energy intensive process often requiring the use of advanced treatment technologies. Stricter effluent standards have resulted in an increase in the number of wastewater treatment plants (WWTPs) with advanced treatment over time. Accordingly, associated energy consumption has also increased. Concerns about lowering operating costs for WWTPs and reducing associated greenhouse gas generation present an incentive to investigate energy use in WWTPs. This research investigated the impact of wastewater strength and the introduction of advanced treatment technologies, to replace traditional technologies on energy use to treat wastewater in WWTPs. Major unit processes were designed for a 100 …

Image Segmentation For Quantification Of Air-Water Interface In Micro-Ct Soil Images, Kranthi Kumar Potteti

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soils are complex environments comprising various biological (roots, water, air etc) and physical constituents (minerals, aggregates, etc). Synchrotron radiation based X-ray microtomography (XMT) is widely used in extracting qualitative and quantitative information regarding spatial distribution of biological and physical soil constituents. Segmentation of these micro-CT soil images is of interest to geologists, hydrologists, civil and petroleum engineers and soil scientists. In this present work, we study and implement segmentation algorithms for microhydrology studies, specifically for soil water conductivity. Three well-known image segmentation algorithms are studied for evaluating their performance for the task. We demonstrate the problems and ways to segment …

Hybrid Plasmonic Nanoantennas: Fabrication, Characterization, And Application, Shengjie Zhai

UNLV Theses, Dissertations, Professional Papers, and Capstones

As optical counterpart of microwave antennas, plasmonic nanoantennas are important nanoscale devices for converting propagating optical radiation into confined/enhanced electromagnetic fields. Presently, nanoantennas, with a typical size of 200-500 nm, have found their applications in bio-sensing, bio-imaging, energy harvesting, and disease cure and prevention. With the device feature size of next generation IC goes down to 22 nm or smaller, and biological/chemical sensing reaches the Gene’s level, the sizes of the corresponding nanoantennas have to be scaled down to sub-100nm level. In the literature, these sub-100nm nanoantennas are referred as deep subwavelength nanoantennas as size of such miniaturized nanoantennas is …

Fabrication And Characterization Of Polylactic Acid And Polylactic Acid/Multi-Walled Carbon Nanotube Nanofibers Through Centrifugal Spinning, Richard Patlan

Theses and Dissertations - UTB/UTPA

Biocompatible polymer nanofibers hold great potential in the biomedical engineering field. Their biodegradable nature and enhanced properties could help solve a wide array of health related problems, particularly in the areas of tissue regeneration, drug delivery, and biosensor design. The novel ForcespinningTM method allows the production of submicron fibers without many of the drawbacks found in electrospinning, while also providing a substantial increase in fiber production. The aim of the study was to utilize this method to fabricate non-woven nanofibrous mats composed of polylactic acid (PLA) and polylactic acid/multi-walled carbon nanotube composite fibers. The morphology, thermal properties, and crystalline structure …

The Control Of Nitrogenous And Carbonaceous Disinfection Byproduct Precursors With Magnetic Ion Exchange, Xiaojie Gan

All Theses

The objective of this study was to examine the potential of the magnetic ion exchange (MIEX®) process to remove nitrogenous disinfection byproduct (N-DBP) precursors while minimizing carbonaceous DBP (C-DBP) precursors in different water matrices. In the first phase of the study, the MIEX® process was tested in raw dinking waters and waters impacted effluent from wastewater treatment plant. Samples were collected from several drinking water/wastewater treatment plants in South Carolina. The effluent impacted source waters were prepared by mixing treated wastewater effluents with a drinking water. For all samples, formation potential (FP) tests were conducted for regulated trihalomethanes (THMs), haloacetic …

Infrared Optical Path Adjustment Method For Common-Path Optical Coherence Tomography, Yanjun Li, Zhongdong Liu, Yinan Zhang, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

A new, common-path, in-axis concentric beam-splitting Michelson interferometer is demonstrated for optical coherence tomography (OCT), which can be used to perform high resolution cross-sectional in vivo and in situ imaging of biological tissues. a piece of glass tube with its inner diameter smaller than the beamwidth of the collimated light is used to split the light into a reference and sample beam. in order to obtain the optimal spectral interferogram of this OCT system, an infrared optical path adjustment method was introduced in this paper. © (2012) Trans Tech Publications, Switzerland.

Assembled Singlemode And Graded Index Fibers Simulating Collimator For All Fiber Common-Path Optical Coherence Tomography, Yanjun Li, Jigui Zhu, Zhongdong Liu, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

A single mode fiber assembled with a specified length graded index multimode fiber as a collimator, which is used in common-path optical coherence tomography (CPOCT) is described in this paper. Compared with conventional collimator lens, this assembled fiber's structure possesses the advantages of small volume, easy to be fused or connected with other part of the CPOCT system. Furthermore, with this assembled structure and all fiber CPOCT system is constructed which has the potential to detect the internal bodily organs and tissues of human being. Numerical simulation and experiments are implemented to verify the effectiveness of this method. © (2012) …