Digital Commons Network^™

Sector Expansion And Elliptical Modeling Of Blue-Gray Ovoids For Basal Cell Carcinoma Discrimination In Dermoscopy Images, Pelin Guvenc, Robert W. Leander, Serkan Kefel, William V. Stoecker, Ryan K. Rader, Kristen A. Hinton, Sherea Monica Stricklin, Harold S. Rabinovitz, Margaret C. Oliviero, Randy Hays Moss

Chemistry Faculty Research & Creative Works

Background: Blue-gray ovoids (B-GOs), a critical dermoscopic structure for basal cell carcinoma (BCC), offer an opportunity for automatic detection of BCC. Due to variation in size and color, B-GOs can be easily mistaken for similar structures in benign lesions. Analysis of these structures could afford accurate characterization and automatic recognition of B-GOs, furthering the goal of automatic BCC detection. This study utilizes a novel segmentation method to discriminate B-GOs from their benign mimics.

Methods: Contact dermoscopy images of 68 confirmed BCCs with B-GOs were obtained. Another set of 131 contact dermoscopic images of benign lesions possessing B-GO mimics provided a …

Separation Of Various Organic-Organic And Aqueous-Organic Solutions Via Pervaporation, John Tang

Dissertations

Pervaporation, an energy saving separation process, can be useful in pharmaceutical processing. However, the organic solvents involved in pharmaceutical product synthesis are chemically demanding; very few polymers are able to withstand them. An ideal membrane would be polymeric having a high thermal, chemical and mechanical stability. Such a membrane is made of a copolymer of polydimethyldioxole and tetrafluoroethylene known as PDD-TFE of the CMS-3 variety with a very high free volume. This novel membrane is used to separate a variety of organic-organic and aqueous-organic mixtures. An earlier study based on water-ethanol-isopropanol has shown evidence that the membrane selectivity may be …

Particle Engineering Via Surface Modification During Micronization For Pharmaceutical Applications, Xi Han

Dissertations

Improving the dissolution rate of Biopharmaceutics Classification System (BCS) class II drugs is an important research area. Micronization which can increase the specific surface area is a promising method to improve the dissolution rate. Micronization alone, however, can lead to downstream processing problems related to poor flow and dispersion properties. The importance of the flowability of pharmaceutical powders is well-documented in the literature. It is, therefore, important to develop a method that can simultaneously overcome these processing issues and allow for micronizing the API. In this work, dry particle coating technique is investigated in the context of micronizing API powders …

Fabrication And Evaluation Of A Collagen-Based Fiber-Gel Three-Dimensional Construct For Peripheral Nerve Repair, Mevan Lakmal Siriwardane

Dissertations

Nerve regeneration following a peripheral nerve injury often relies on growth cone- mediated guidance and the presence of Schwann cells to support the regenerating axons and remyelinate portions of denervated nerve pathways. The emphasis of this work is to develop a synthetic nervous tissue construct that contains similar basal lamina or extracellular matrix to peripheral nerve in order to achieve a level of effectiveness in nerve repair and future peripheral nerve regeneration applications. To this end, three- dimensional nervous tissue constructs consisting of type I collagen are fabricated into a composite biomaterial scaffold to promote contact-guided growth of neuronal and …

Mathematical Modeling Of Heavy Metals Diffusion And Removal From Cylindrical Cement Forms Coated With Bio-Film, Mojdeh Tabatabaie

Dissertations

A mathematical model is developed to predict bioleachi ng of heavy metals from long cylindrical shape cementitious samples. In this model, the metal concentration difference within the solid and its surface is considered as the main driving force for transport of metals to the surface of a sample at a given temperature and pressure. Fick’s first and second law are applied to explain the motion of contaminants in a long and uniform cylindrical solid. In addition, the model considers Michaelis-Menten type kinetics, a special case of the widely accepted Langmuir-Hinshelwood reaction mechanism, at the surface of the encapsulating cylinder. The …

Multifunctional Oxidation Electrocatalysts For Direct Alkaline Fuel Cells, Ulises Martinez

Chemical and Biological Engineering ETDs

The need for the development of new technologies to reduce our dependence on fossil fuels requires the combination of different energy sources such as wind, solar, nuclear as well as new energy storage and powering devices. Amongst these new technologies fuel cells are a promising technology capable of transforming chemical energy stored in fuels into electric power at higher efficiencies than combustion processes. However, the commercialization of fuel cells has been limited due to the high costs associated with electrocatalysts needed for the corrosive environments in which proton-exchange membrane fuel cells operate. Electrocatalysts for such fuel cells are based on …

Impact Of Carbon Support Chemistry, Morphology, And Structure On Platinum Catalyst Durability For Pemfc Applications, Anant Patel

Chemical and Biological Engineering ETDs

Polymer electrolyte membrane fuel cells are a promising alternative energy source, capable of being deployed as successful replacements in many stationary and mobile applications. These devices, however, lack durability, and this has become one of the limiting factors for commercialization. Many projects have focused on finding ways to improve their lifetimes, but few have tried to examine the underlying causes behind their corrosion. The goal of this project was to identify which parameters have a significant impact, both positive and negative, on PEMFC durability. To do this, three series of samples were analyzed using microscopic, spectroscopic, and electrochemical methods. Electron …

On The Spatial Predictability Of Wireless Channels And Robust Networked Cooperation In Mobile Sensor Networks, Mehrzad Malmirchegini

Electrical and Computer Engineering ETDs

The wireless sensor network revolution has created the possibility of exploring and controlling the environment in ways not possible before. The vision of a multi-agent network cooperatively learning and adapting in harsh unknown environments to achieve a common goal is closer than ever. In such networks, communication plays a key role in the overall performance of the network as each mobile agent improves its knowledge by processing the information received from others. Therefore, proper prediction of the communication signal strength and fundamentally understanding the spatial predictability of a wireless channel, based on only a few measurements, become considerably important. The …

Diffuse Axonal Injury Effect On Myelinating Cells And Axons, Jennifer Alison Zalk

Theses

There is no supporting evidence whether myelin degeneration in diffuse axonal injury (DAI) of the white matter is due to death of myelinating oligodendrocytes or secondary axotomy. Cortical neurons are not able to remain healthy in culture to have their axons myelinated. Dorsal root ganglion (DRG) neurons have been shown to be myelinated by cortical oligodendrocytes in culture. An in vitro stretch injury model was used to analyze the DRG axon pathology during and after injury. DRG myelinating Schwann cells are analyzed to demonstrate what is expected from injury to oligodendrocytes. DRG axons demonstrated a high tolerance to stretch …

Quantification Of Human Motion On Roller Coaster Rides, Chirag Burman

Theses

Case reports have been published of people experiencing symptoms of traumatic brain injury (TBI) and/or ailments of the vascular tissue around the head. These reports pointed towards G-forces, a scalar measure without a specified direction, which represent the measure of the acceleration of an object divided by acceleration caused by gravity (9.81 m/s²), as a cause of said injuries. Research has been conducted on quantifying the G-forces experienced while on roller coasters, as well as the change in heart rate. However these studies have not been able to show a link between roller-coasters and symptoms.

This thesis aims …

Biological And Biomimetic Oxygen Electro-Reduction By Enzymes, Shayna Brocato

Chemical and Biological Engineering ETDs

Enzyme catalysts are a viable alternative to the traditional platinum based catalysts for the complete oxidation of complex fuels. Efficient oxidation of multi-carbon compounds, selective catalytic activity eliminating the need for fuel purification, and high performance under mild temperature and pH conditions make enzyme catalysts appealing for applications in vivo, implantable, and in vitro, portable energy sources. The full catalytic potential of enzymes can only be obtained if the full energy potential of a biofuel, complete oxidation to CO2, is obtained; this requires multiple reactions, i.e. multiple enzymes or an enzyme cascade. The efficiency of enzyme cascades improves with quaternary …

An Investigation Of The Potential For And Application Of Life Cycle Analysis In The Pharmaceutical Industry, Michael Raymond

Theses and Dissertations

Life cycle assessment offers a unique opportunity to analyze emission reductions across all manufacturing sectors. However, few efforts have been made to apply this method to the pharmaceutical industry. The Toxic Release Inventory is a powerful tool to determine areas of high potential for emissions reductions in industry. When applied to the pharmaceutical industry and coupled with a life cycle assessment, areas for significant environmental improvement become apparent. By examining these trends and exploring a variety of emissions reductions techniques, life cycle emissions in these problem areas may be significantly reduced. These trends demonstrate that manufacture of virgin solvent and …

Quantification Of In Vivo Oxidative Damage In Caenorhabditis Elegans During Aging By Endogenous F3-Isoprostane Measurement, Christiaan F. Labuschagne, Edwin C.A. Stigter, Margriet M.W.B. Hendriks, Ruud Berger, Joshua Rokach, Hendrik C. Korswagen, Arjan B. Brenkman

Chemistry and Chemical Engineering Faculty Publications

Oxidative damage is thought to be a major cause in development of pathologies and aging. However, quantification of oxidative damage is methodologically difficult. Here, we present a robust liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach for accurate, sensitive, and linear in vivo quantification of endogenous oxidative damage in the nematode Caenorhabditis elegans, based on F3-isoprostanes. F3-isoprostanes are prostaglandin-like markers of oxidative damage derived from lipid peroxidation by Reactive Oxygen Species (ROS). Oxidative damage was quantified in whole animals and in multiple cellular compartments, including mitochondria and peroxisomes. Mutants of the mitochondrial electron transport proteins mev-1 and clk-1 showed increased oxidative damage …

Detection And Classification Of Diabetic Retinopathy Pathologies In Fundus Images, Carla Paola Agurto Rios

Electrical and Computer Engineering ETDs

Diabetic Retinopathy (DR) is a disease that affects up to 80% of diabetics around the world. It is the second greatest cause of blindness in the Western world, and one of the leading causes of blindness in the U.S. Many studies have demonstrated that early treatment can reduce the number of sight-threatening DR cases, mitigating the medical and economic impact of the disease. Accurate, early detection of eye disease is important because of its potential to reduce rates of blindness worldwide. Retinal photography for DR has been promoted for decades for its utility in both disease screening and clinical research …

Nanomechanical Characterization Of Asphalt, Hasan Faisal

Civil Engineering ETDs

In this study, asphalt binder and asphalt concrete (AC) materials are characterized using laboratory nanoindentation testing and mechanical models. Traditionally, laboratory nanoindentation test data is analyzed using the Oliver-Pharr method to determine elastic modulus and hardness of materials. In a nanoindentation test, a test sample surface is indented or loaded by a hard indenter tip and then unloaded. In the past, several studies of the polymer materials area have selected a loading rate and dwell time (i.e., the peak load is kept constant for a few seconds before unloading) to avoid or minimize the viscous effect of a material. No …

Flow In Thin Regions Bounded By Structured And Porous Surfaces : Applications To Load Bearings, Abishek Venkatakrishnan

Chemical and Biological Engineering ETDs

The effect of surface roughness on the load capacity and friction force of hydrodynamic bearings has received considerable interest from scientists and engineers. Surfaces of most engineered materials are textured at some level either deliberately to achieve some desired effect or produced by wear and friction of surfaces. This thesis analyses the effect of surface roughness and porosity on the load capacity of hydrodynamic bearings. The surface roughness is characterized by a single sinusoidal wave function. The implementation of sinusoidal roughness model is verified using a verification problem. Reynolds lubrication theory, derived from thin-region approximations of the Navier-Stokes equations, is …

A Novel Fast Solver For Poisson's Equation With Neumann Boundary Condition, Zuhui Ma, Weng Cho Chew, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we present a novel fast method to solve Poisson's equation in an arbitrary two dimensional region with Neumann boundary condition, which are frequently encountered in solving electrostatic boundary problems. The basic idea is to solve the original Poisson's equation by a two-step procedure. In the first stage, we expand the electric field of interest by a set of tree basis functions and solve it with a fast tree solver in O(N) operations. The field such obtained, however, fails to expand the exact field because the tree basis is not curl-free. Despite of this, we can retrieve the …

Scanning In Situ Spectroscopy Pplatform For Imaging Surgical Breast Tissue Specimens, Venkataramanan Krishnaswamy, Ashley M. Laughney, Wendy A. Wells, Keith D. Paulsen, Brian W. Pogue

Dartmouth Scholarship

A non-contact localized spectroscopic imaging platform has been developed and optimized to scan 1 x 1 cm² square regions of surgically resected breast tissue specimens with ~150-micron resolution. A color corrected, image-space telecentric scanning design maintained a consistent sampling geometry and uniform spot size across the entire imaging field. Theoretical modeling in ZEMAX allowed estimation of the spot size, which is equal at both the center and extreme positions of the field with ~5% variation across the designed waveband, indicating excellent color correction. The spot sizes at the center and an extreme field position were also measured experimentally using the …

Automated Point-Of-Care Image Processing Methodology For The Diagnosis Of Malaria, Michael B. Jorgensen

Master's Theses

Malaria has profoundly influenced human history for over four thousand years and despite numerous attempts at eradication, the prevention, diagnosis, and treatment of malaria have been largely ineffective. More than five hundred million people are affected by malaria every year resulting in over one million deaths. Drug resistance development by the parasite has diminished the effectiveness of numerous treatment options due, in part, to overtreatment of negative patients based on insufficient clinical algorithms and diagnostic methods. The goal of this research was to develop an image analysis algorithm to diagnose malaria with a high degree of sensitivity and specificity in …

The Santa Clara, 2013-01-24, Santa Clara University

The Santa Clara

No abstract provided.

Polystyrene Microsphere And 5-Fluorouracil Release From Custom Designed Wound Dressing Films, Maryam Mobed-Miremadi, Raki Komarla Nagendra, Sujana Lakshmi Ramachandruni, Jason James Rook, Mallika Keralapura, Michel Goedert

Bioengineering

Custom-designed wound dressing films of chitosan and alginate have been prepared by a casting/solvent evaporation method for hydrophobic therapeutic agent encapsulation. In this parametric study, the propylene glycol (PG) and calcium chloride (CaCl₂) concentrations were varied for chitosan and alginate films, respectively. Mechanical and chemical inter-related responses under observations included thickness (th), elasticity (E), tensile strength (TS), sorption ability (S%) and kinetics of in-vitro drug release, specifically in terms of membrane time to burst (tB) and duration of release (tR). As shown by results of a one tailed t-test significance testing at the 95% confidence interval (α = …

The Nucleus 2012-2013, Rrosalie A. Richards

Science Education Center

No abstract provided.

Scaffold For Bone And Tissue Repair In Mammals, D. E. Day, Steven B. Jung

Materials Science and Engineering Faculty Research & Creative Works

A mammalian tissue scaffold and method for making a tissue scaffold including a rigid scaffold body of biocompatible glass fibers bonded together and in special alignment to define open channels within the scaffold to allow fluid flow into and within the scaffold.

Hydrodynamics Of Pilot-Scale Bubble Columns: Effect Of Internals, Ahmed A. Youssef, Mohamed E. Hamed, Joshua T. Grimes, Muthanna H. Al-Dahhan, Milorad P. Duduković

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Gas Holdup and Bubble Characteristics Are Key Parameters that Affect the Performance of Bubble Columns. an Experimental Study of the Effect of Heat Exchanging Internals on the Gas Holdup, Bubble Dynamics, and their Radial Profiles is Performed. an Air-Water System is Used in a Plexiglas Column 45 Cm (18 In.) in Diameter. Internals Configurations Mimicking Those Typical for the Liquid-Phase Methanol Synthesis and Fischer-Tropsch Process and Covering 5% and 25%, Respectively, of the Total Cross-Sectional Area of the Column, Are Investigated. High Superficial Gas Velocities that Fall within the Churn Turbulent Flow Regime, Which Are of Interest for Most …

Dual-Tracer Background Subtraction Approach For Fluorescent Molecular Tomography, Kenneth M. Tichauer, Robert W. Holt, Fadi El-Ghussein, Scott C. Davis, Kimberly S. Samkoe, Jason R. Gunn, Frederic Leblond, Brian W. Pogue

Dartmouth Scholarship

Diffuse fluorescence tomography requires high contrast-to-background ratios to accurately reconstruct inclusions of interest. This is a problem when imaging the uptake of fluorescently labeled molecularly targeted tracers in tissue, which can result in high levels of heterogeneously distributed background uptake. We present a dual-tracer background subtraction approach, wherein signal from the uptake of an untargeted tracer is subtracted from targeted tracer signal prior to image reconstruction, resulting in maps of targeted tracer binding. The approach is demonstrated in simulations, a phantom study, and in a mouse glioma imaging study, demonstrating substantial improvement over conventional and homogenous background subtraction image reconstruction …

Advanced Optimization Techniques For Monte Carlo Simulation On Graphics Processing Units, Eyad Hailat

Wayne State University Dissertations

The objective of this work is to design and implement a self-adaptive parallel GPU optimized Monte Carlo algorithm for the simulation of adsorption in porous materials. We focus on Nvidia's GPUs and CUDA's Fermi architecture specifically. The resulting package supports the different ensemble methods for the Monte Carlo simulation, which will allow for the simulation of multi-component adsorption in porous solids. Such an algorithm will have broad applications to the development of novel porous materials for the sequestration of CO2 and the filtration of toxic industrial chemicals.

The primary objective of this work is the release of a massively parallel …

Multiplexed Photometry And Fluorimetry Using Multiple Frequency Channels, Khaled M. Dadesh

Wayne State University Dissertations

ABSTRACT

MULTIPLEXED PHOTOMETRY AND FLUORIMETRY USING MULTIPLE FREQUENCY CHANNELS

by

KHALED M. DADESH

August 2013

Advisor: Dr. Amar Basu

Major: Electrical Engineering

Degree: Doctor of Philosophy

Multispectral photometry and fluorimetry are useful for quantifying and distinguishing samples during flow injection analysis, flow cytometry, and ratiometric absorbance measurement. However, multispectral detectors, including spectrometers, typically require arrayed or multiple light detectors, optical components, and path alignments, all of which increases the size and cost of the detection system. Several previous efforts have attempted the use of time division multiplexing or frequency division multiplexing (FDM) techniques to minimize both size …

Effect Of Intake Temperature And Boost Pressure On The Auto-Ignition Of Fuels With Different Cetane Numbers And Volatilities, Chandrasekharan Jayakumar

Wayne State University Dissertations

The aim of this research is to investigate the effect of air inlet temperature and boost pressure on the auto-ignition of fuels that have different CNs and volatilities in a single cylinder diesel engine. The inlet air temperature is varied over a range of 30°C to 110°C at a constant intake pressure of 1.1 bar. The boost pressure is varied from 1.1 bar to 1.5 bar at a constant intake temperature of 60°C. All engine tests are run at steady-state conditions. The fuels used are ultra-low-sulfur-diesel (ULSD), JP-8 (two blends with CN 50 & 31) and F-T SPK. Detailed analysis …

2013 Nebraska Water Monitoring Programs Report, Marty Link, Joe Kenning

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain good quality water and encourage or execute activities to improve poor water quality. Monitoring is done on the over 16,000 miles of flowing rivers and streams, our greater than 148,000 acres of surface water in lakes and reservoirs, and the vast storage of groundwater in Nebraska’s aquifers.

Self-Healing Of Ionomeric Polymers With Carbon Fibers From Medium-Velocity Impact And Resistive Heating, Vishnu Baba Sundaresan, Andrew Morgan, Matt Castellucci

Mechanical and Nuclear Engineering Publications

Self-healing materials science has seen significant advances in the last decade. Recent efforts have demonstrated healing in polymeric materials through chemical reaction, thermal treatment, and ultraviolet irradiation. The existing technology for healing polymeric materials through the aforementioned mechanisms produces an irreversible change in the material and makes it unsuitable for subsequent healing cycles. To overcome these disadvantages, we demonstrate a new composite self-healing material made from an ionomer (Surlyn) and carbon fiber that can sustain damage from medium-velocity impact and heal from the energy of the impact. Furthermore, the carbon fiber embedded in the polymer matrix results in resistive heating …