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A New Computational Model To Augment The Design Of Microfluidic Separations: Electric Field Assisted, Hydrodynamic Chromatography, Jeffrey D. Wells Jun 2012

A New Computational Model To Augment The Design Of Microfluidic Separations: Electric Field Assisted, Hydrodynamic Chromatography, Jeffrey D. Wells

Master's Theses

This project encompasses the implementation of a computational model to simulate the microfluidic separation of like-charged particles in a continuous flow environment. By accomplishing this task the model can be used to optimize future fractionations by tailoring the process parameters to the properties of the target particles. The primary goal of this project is to develop a vectorized code within Matlab® that captures a sufficient quantity of the physics in separations to assist with the optimization and design of microfluidic systems.

This project differs from other computational models in that it utilizes a personal computer to run the simulation in …


Cascaded High Voltage Converter With Variable Control For Pulsed Electric Field Applications, Emmanuel Loza Jun 2012

Cascaded High Voltage Converter With Variable Control For Pulsed Electric Field Applications, Emmanuel Loza

Master's Theses

Living a sustainable lifestyle while facing increasing population and decreasing natural resources has become one of humanity’s largest challenges. Locating fossil fuels is becoming more difficult while the demand for them to power our societies is ever increasing. Instead of finding more efficient methods of extracting fossil fuels, developing technologies that create renewable substitutes for fossil fuels is now the strategy. Algae biofuel matches fossil fuel performance while also meeting the criteria for renewable energy. The focus now shifts to finding methods for commercially producing algae biofuel. Therefore, the objective of this thesis is to develop a system that provides …


Feasibility Study Into The Use Of 3d Printed Materials In Cubesat Flight Missions, Daniel Fluitt Jun 2012

Feasibility Study Into The Use Of 3d Printed Materials In Cubesat Flight Missions, Daniel Fluitt

Master's Theses

The CubeSat Program has provided access to space for many universities, private companies, and government institutions primarily due to the low cost of CubeSat satellite development. While these costs are orders of magnitude lower than similarly capable nano-satellite missions, they are still outside of the budgetary constraints of many potential developers including university and high school clubs. Using 3D printed plastics in the production of CubeSat structures and mechanisms presents a large cost savings opportunity that will allow these institutions to participate in the development of these satellites, expanding the educational and scientific impact of the CubeSat Program.

Five rapid …


The Characterization Of Biofilm Attachment To Metal Interfaces: Effects Of Substratum Properties, Marcel D. Mendes Jun 2012

The Characterization Of Biofilm Attachment To Metal Interfaces: Effects Of Substratum Properties, Marcel D. Mendes

Master's Theses

Bacteria are among the most abundant microorganisms on earth, and can be found in essentially every environment. When a clean surface is exposed to media containing planktonic bacteria, the bacterial cells will attach to the surface and aggregate to form what is known as a biofilm. Biofilms have been shown to negatively affect many industries including medical, industrial, and food science applications. While biofilms have been well characterized from a microbiology perspective, there has been much less research from a materials science standpoint. It is hypothesized that the material properties of the substratum (such as the micro-structure) have a significant …


Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Brain Barrier Model, Deven Chandrakant Patel Jun 2012

Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Brain Barrier Model, Deven Chandrakant Patel

Master's Theses

Developing an in vitro Blood Brain Barrier model that will replicate the physiological, anatomical, and functional characteristics of the native BBB has gained significant attention. Such a model would enable prediction of the penetration of CNS targeting drug candidates across the BBB, allow pre-screening and optimization strategies to be developed for new drugs and gene delivery formulations, and permit research groups to further understand how a dysfunctional BBB is involved in the pathogenesis of several neurological diseases.

The Tissue Engineering laboratory at the California Polytechnic State University, San Luis Obispo is currently in the process of developing a dynamic in …


Development And Characterization Of Phospholipid Encapsulated Quantum Dot Constructs For Biologic Applications, Laura C. Sparks Jun 2012

Development And Characterization Of Phospholipid Encapsulated Quantum Dot Constructs For Biologic Applications, Laura C. Sparks

Master's Theses

DEVELOPMENT AND CHARACTERIZATION OF PHOSPHOLIPID ENCAPSULATED QUANTUM DOT CONSTRUCTS FOR BIOLOGIC APPLICATIONS

The American Cancer Society predicts that 577,190 cancer-related deaths and 1,638,910 newly diagnosed cases of cancer will occur in 2012. As these statistics show, cancer is a prevalent and devastating health issue; determined by the Mayo Clinic to be the second leading cause of death in the United States. Skin cancer is the most common form of cancer in the United States. In 2012 more than 68,000 Americans will be diagnosed with melanoma, 48,000 will be diagnosed with an early form of the disease that has not yet …


Hydraulically Driven Mechanical Representation Of A Biological System, Andrea Argouarch, Michael Mceachern, Brandon Parham Jun 2012

Hydraulically Driven Mechanical Representation Of A Biological System, Andrea Argouarch, Michael Mceachern, Brandon Parham

Biomedical Engineering

No abstract provided.


Development And Characterization Of Plga And Eptfe Blood Vessel Mimics Using Gene Expression Analysis, Michael Gibbons, Sarah Ur Jun 2012

Development And Characterization Of Plga And Eptfe Blood Vessel Mimics Using Gene Expression Analysis, Michael Gibbons, Sarah Ur

Biomedical Engineering

Tissue engineered blood vessels (TEBV’s) have the potential to act not only as a replacement for diseased vessels, but also as a testing platform for intravascular devices such as stents. To this end, the goal of this study was to develop protocols for the construction of TEBV’s composed of human vascular cells and either expanded polytetrafluoroethylene (ePTFE) or poly-lactic-co-glycolic acid (PLGA), as well as a protocol for gene expression in those TEBV’s. Initial experiments involved only human umbilical vein endothelial cells (HUVEC’s), but after low cell confluency and spreading in single-sodded vessels a second cell type, human umbilical vein smooth …


Co-Removal Of Atrazine And Nitrate From Groundwater Using A Mulch Biofilm, Allison L. Cole Jun 2012

Co-Removal Of Atrazine And Nitrate From Groundwater Using A Mulch Biofilm, Allison L. Cole

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The popular broadleaf herbicide atrazine is often found in contaminated groundwater along with other agricultural chemicals, such as nitrate. Mulch biowalls, a passive treatment placed in situ, can inexpensively remediate groundwater by intercepting and treating a contaminant plume. Three types of organic mulch: cedar, cypress, and hardwood were evaluated for their ability to act as supporting materials for a biowall to simultaneously remove atrazine and nitrate from groundwater. Physical and chemical properties of the mulch were characterized. Cedar mulch had the highest organic carbon content, 996 mg/g. The adsorptive capacity of the mulch for atrazine and nitrate, in mono …


Wireless Medical Sensor Networks: Design Requirements And Enabling Technologies, Cecilia H. Vallejos De Schatz, Henry P. Medeiros, Fabio K. Schneider, Paulo J. Abatti Jun 2012

Wireless Medical Sensor Networks: Design Requirements And Enabling Technologies, Cecilia H. Vallejos De Schatz, Henry P. Medeiros, Fabio K. Schneider, Paulo J. Abatti

Electrical and Computer Engineering Faculty Research and Publications

This article analyzes wireless communication protocols that could be used in healthcare environments (e.g., hospitals and small clinics) to transfer real-time medical information obtained from noninvasive sensors. For this purpose the features of the three currently most widely used protocols—namely, Bluetooth® (IEEE 802.15.1), ZigBee (IEEE 802.15.4), and Wi-Fi (IEEE 802.11)—are evaluated and compared. The important features under consideration include data bandwidth, frequency band, maximum transmission distance, encryption and authentication methods, power consumption, and current applications. In addition, an overview of network requirements with respect to medical sensor features, patient safety and patient data privacy, quality of service, and interoperability …


An Inverted Teaching Model For A Mechanics Of Materials Course, Jeffery S. Thomas, Timothy A. Philpot Jun 2012

An Inverted Teaching Model For A Mechanics Of Materials Course, Jeffery S. Thomas, Timothy A. Philpot

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Instructors at Missouri University of Science and Technology have been offering certain sections of a mechanics of materials course in an inverted format for the past two years. In this format, students learn the concepts outside of class, using a textbook, animations and videos developed by the authors, and work on homework either individually or in groups during the optional class time. Students take eight multiple-choice exams and a final exam that is common to both the inverted sections and the more traditional lecture-based sections. Homework in the inverted sections is assigned but not graded. The in-class exams are given …


Scalable Synthesis Of Palladium Nanoparticle Catalysts By Atomic Layer Deposition, Xinhua Liang, Lauren B. Lyon, Ying Bing Jiang, Alan W. Weimer Jun 2012

Scalable Synthesis Of Palladium Nanoparticle Catalysts By Atomic Layer Deposition, Xinhua Liang, Lauren B. Lyon, Ying Bing Jiang, Alan W. Weimer

Chemical and Biochemical Engineering Faculty Research & Creative Works

Atomic layer deposition (ALD) was used to produce Pd/Al2O 3 catalysts using sequential exposures of Pd (II) hexafluoro acetylacetonate and formalin at 200 °C in a fluidized bed reactor. the ALD-prepared Pd/alumina catalysts were characterized by various methods including hydrogen chemisorption, XPS, and TEM, and compared with a commercially available 1 wt.% Pd/alumina catalyst, which was also characterized. the content of Pd on alumina support and the size of Pd nanoparticles can be controlled by the number of ALD-coating cycles and the dose time of the Pd precursor. One layer of organic component from the Pd precursor remained on the …


Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan Jun 2012

Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The risk of bioterrorism events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. This report describes nanoenergetic gas generators (NGG) system that exhibit long term stability and superior release of biocidal substances for destruction of pathogenic bacteria. The effect of iodine vaporization on destroying of Escherichia coli (E-coli, HB101 K-12 strain) by using expressing Green Fluorescent Protein (GFP) was investigated. HB101 K-12 has been genetically modified to prevent its growth unless grown on an enriched medium. To obtain quantitative data we used pGLO transformation …


Optimized Monopole And Dipole Antennas For Uwb Asset Tag Location Systems, Antoine Dumoulin, Matthias John, Max Ammann, Patrick Mcevoy Jun 2012

Optimized Monopole And Dipole Antennas For Uwb Asset Tag Location Systems, Antoine Dumoulin, Matthias John, Max Ammann, Patrick Mcevoy

Articles

Miniaturized monopole and dipole antenna designs are reported with performances optimized for ultrawideband pulsed radio applications. The geometries are created using Bézier spline shapes, which have been refined with a genetic algorithm to simultaneously take account of both frequency- and time-domain criteria. Time-domain measurements of ultra wideband antennas with uniformly distributed energy across the full 3.1-10.6 GHz mask are reported for the first time and validate a new approach to minimization of pulse dispersion effects in the antenna designs.


Advanced Intelligent Control And Optimization For Cardiac Pacemaker Systems, Wei Shi May 2012

Advanced Intelligent Control And Optimization For Cardiac Pacemaker Systems, Wei Shi

Dissertations

Since cardiovascular diseases are major causes of morbidity and mortality in the developed countries and the number one cause of death in the United States, their accurate diagnosis and effective treatment via advanced cardiac pacemaker systems have become very important. Intelligent control and optimization of the pacemakers are significant research subjects. Serious but infrequently occurring arrhythmias are difficult to diagnose. The use of electrocardiogram (ECG) waveform only cannot exactly distinguish between deadly abnormalities and temporary arrhythmias. Thus, this work develops a new method based on frequency entrainment to analyze pole-zero characteristics of the phase error between abnormal ECG and entrained …


Investigation Of The Fracture Phenomena During The Milling Process Of Inorganic Particulates And Brittle Fracture Of Polymer Composites Using Fractal Theory, Zheng Qian May 2012

Investigation Of The Fracture Phenomena During The Milling Process Of Inorganic Particulates And Brittle Fracture Of Polymer Composites Using Fractal Theory, Zheng Qian

Dissertations

This dissertation investigates the applicability and usefulness of applying Fractal mathematics and to the fracture of brittle particulates in Fluid Energy Mill devices, and in particular quantifying the resulting power law particle size distributions, examining the Surface Fractal Dimension of milled particulates, and relating the Izod Impact Strength values of composites of polypropylene and Calcium carbonate particulates which are large un-milled, small milled, as well as small and produced by the simultaneous milling and coating with nano-silica to the Surface Fractal Dimension of the impact fracture surfaces.

First, the dissertation examines the behavior of un-coated and micron-sized wax pre-coated particulates …


Virtual Reality Visual Feedback And Its Effect On Brain Excitability, Soha Saleh May 2012

Virtual Reality Visual Feedback And Its Effect On Brain Excitability, Soha Saleh

Dissertations

This dissertation examines manipulation of visual feedback in virtual reality (VR) to increase excitability of distinct neural networks in the sensorimotor cortex. The objective is to explore neural responses to visual feedback of motor activities performed in complex virtual environments during functional magnetic resonance imaging (fMRI), and to identify sensory manipulations that could further optimize VR rehabilitation of persons with hemiparesis. In addition, the effects of VR therapy on brain reorganization are investigated. An MRI-compatible VR system is used to provide subjects with online visual feedback of their hand movement. First, the author develops a protocol to analyze variability in …


Adsorption Of Particles On Fluid-Liquid Interfaces, Bhavin Dalal May 2012

Adsorption Of Particles On Fluid-Liquid Interfaces, Bhavin Dalal

Dissertations

Particles floating on fluid-liquid interfaces are of considerable interest because of their importance in a range of physical applications and biological processes, e.g., self-- assembly of particles at fluid-fluid interfaces resulting in novel nano structured materials, stabilization of emulsions, formation of pollen and insect egg rafts, etc. The aim of this dissertation is to explore the mechanism by which particles are adsorbed at fluid-liquid interfaces. It is shown that the inertia of a particle plays an important role in its motion in the direction normal to a fluid-liquid interface, and in determining the particles adsorption trajectory and orientation in …


Rational Design Of Hydrogen-Free Catalytic Active Sites, Andrei Ioan Loas May 2012

Rational Design Of Hydrogen-Free Catalytic Active Sites, Andrei Ioan Loas

Dissertations

Materials that are organic-based and exhibit oxidative catalytic activity, including free-radical pathways, while being refractory to the activated oxygen species are not known. The synthesis of several classes of such materials, their electronic and structural characterizations as well as catalytic properties are reported. Their rational molecular design and biologically inspired reactivity are based on enzymatic active sites, which are reengineered into robust metal-organic fluoroalkylated scaffolds that, for the first time, exhibit structural asymmetry and tunable π-π interactions both in solution and solid state. In these complexes, labile C-H bonds are replaced with chemically and thermally resistant C-F bonds to create …


Desalination Of Brine And Produced Water By Membrane Distillation At Lower As Well As Higher Temperatures And Pressures, Dhananjay Singh May 2012

Desalination Of Brine And Produced Water By Membrane Distillation At Lower As Well As Higher Temperatures And Pressures, Dhananjay Singh

Dissertations

Direct contact membrane distillation (DCMD)-based desalination process is a thermally- driven separation process where a hydrophobic microporous membrane separates a hot brine feed and a cold distillate which condenses the water vapor from the hot brine passing through the membrane pores. So far, DCMD has been explored for hot brines and other aqueous solutions below 100oC. For feed solutions above 100oC, DCMD has an extra advantage over other conventional separation processes like reverse osmosis (RO) which requires cooling of the feed solution costing additional energy; further, RO can not utilize the heat available in the feed solution. Produced water obtained …


Inkjet Printing Of Resistive-Type Humidity Sensor For Harsh Environments, Hamed Kazerani May 2012

Inkjet Printing Of Resistive-Type Humidity Sensor For Harsh Environments, Hamed Kazerani

Dissertations

A flexible resistive-type humidity sensor for harsh environments is successfully designed and fabricated by an inkjet printing method using a Dimatix materials printer (DMP-2800 series from Fujifilm). Construction of the sensors is based on inkjet printed interdigitated silver electrodes on a polyimide flexible substrate along with an inkjet printable polyaniline (PANi) as humidity sensitive material. A copolymer of ethylene and vinyl alcohol (EVOH) is used as sensor protective coating. Double strand water- soluble PANi ink is synthesized by polymerization of aniline monomers with poly(4- styrenesulfonic acid) (PSSA) as a template.

Manufactured devices showed high sensitivity (/% @ 45%RH) to humidity …


Fmri Assessment Of Ischemic Stroke In Humans, Rui Yuan May 2012

Fmri Assessment Of Ischemic Stroke In Humans, Rui Yuan

Theses

Cerebral ischemia, or brain ischemia is a kind of stroke where the blood flow is insufficient to the metabolic demand of brain. The lack of oxygen supply will directly lead to the death of brain tissue. There are two major injury regions: the infarct and penumbra. Mostly, since the infarct regions became dead tissues rapidly after stroke, there is a tiny possibility to rescue them in time. But penumbra parts are different. Tissues there will be viable for hours after ischemia. Hence, both theoretically and practically, it is possible to salvage those cells in the penumbra region. Diffusion weighted image …


Magnetic Targeted Drug Delivery System In Gene Therapy, Weilong Lu May 2012

Magnetic Targeted Drug Delivery System In Gene Therapy, Weilong Lu

Theses

Drug delivery system is a method to transport the drug of the required amount accurately to the targeted diseased part. Recently, the concept of Magnetic Targeted Drug Delivery System (MTDDS), based upon magnetic particles under the action of an external magnetic field, exhibits considerable potential for a wide range of medical applications. Gene therapy is the insertion of genes into an individual's cells and tissues to treat diseases. As the recombinant virus vector has many limits and problems, more studies turn to the nonvirus vectors, which have transfection efficiency and low cytotoxicity. PLLA(poly(L lactic acid)) can be biodegradable and has …


Alterations In Brain Connectivity After Spinal Cord Injury Using Functional Mri, Yamin Ahmed Noor May 2012

Alterations In Brain Connectivity After Spinal Cord Injury Using Functional Mri, Yamin Ahmed Noor

Theses

Every year, approximately 50 people per million of inhabitants are inflicted by Spinal Cord Injury (SCI). The long-term impairment of the SCI patients has led researchers to investigate different rehabilitation and treatment efforts that require careful observations to be made on reliable markers. Presently, a number of neuropsychological assessments are used for SCI rehabilitation and research purposes. However, there is a need for the discovery of sensitive biomarkers that can be used to characterize SCI. Altered functional connectivity in the brain has been observed in a number of neurological patient populations. Hence, it was hypothesized that such alterations in brain …


Analysis Of Tissue Engineering Strategies For Bone-Related Applications, Timothy Buirkle May 2012

Analysis Of Tissue Engineering Strategies For Bone-Related Applications, Timothy Buirkle

Theses

Over the past few decades, tissue engineering approaches have pushed their way to the forefront of biotechnological research and development, serving a wide variety of applications. This research utilizes quantitative methods to analyze the outcome of two bone tissue engineering studies. In an in vivo study, the use of Negative Pressure Wound Therapy (NPWT) in combination with stem cell-loaded scaffolds was investigated for the repair of large bone defects. Quantitative histological analysis was performed by determining both the percentage of cells proliferating (BrdU), as well as cells expressing bone-specific markers of alkaline phosphatase (A L P) in the defect. Total …


Experimental Evaluation Of Near Infrared Light Penetration Into Neural Tissue, Ujwal Anil Parikh May 2012

Experimental Evaluation Of Near Infrared Light Penetration Into Neural Tissue, Ujwal Anil Parikh

Theses

Near infrared (NIR) lasers find applications in medicine both for diagnostic and treatment purposes. Penetration depth into the tissue is a critical parameter to be considered in these NIR laser applications. Published data on the optical properties of rodent neural tissue are rare, despite the frequent use of rats as animal models. The aim of this study was to directly measure the light intensity profile inside the rat brain gray matter that is illuminated by an NIR laser beam. The local light intensities were sampled using an optical fiber inserted into the brain. The intensity profile in the axial direction …


Hydrodynamic Effects Of An Arch-Shaped Fiber Optic Probe In A Dissolution Testing Apparatus 2, Yiran Zhang May 2012

Hydrodynamic Effects Of An Arch-Shaped Fiber Optic Probe In A Dissolution Testing Apparatus 2, Yiran Zhang

Theses

Dissolution testing is widely used in the pharmaceutical industry to evaluate newly developed drug formulations and as a quality control method to insure that solid dosage forms have consistent dissolution property. Typically, samples are manually drawn from the dissolution vessel prior to analysis. An approach to overcome the limitations of manual sampling consists in the use of sampling probes, such as fiber optic probes, permanently inserted in the dissolution medium and continually sampling the drug concentration in it as the solid dosage form dissolves. Despite their advantages, permanently inserted fiber optic probes can alter the normal fluid flow within the …


Simulation Of Polymer Solar Cell Characteristics By Amps-1d, Lu Zhang May 2012

Simulation Of Polymer Solar Cell Characteristics By Amps-1d, Lu Zhang

Theses

Simulation of polymer solar cell characteristics is presented in this study. The solar cells are made of materials such as the following: Poly (3-hexylthiophene): [6, 6]-phenyl C61- butyric acid methylester (P3HT: PCBM) and poly[2,1,3-benzothiadiazole-4,7-diyl[4,4- bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]: [6, 6]-phenyl C61- butyric acid methylester (PCPDTBT: PCBM) are used as active layer materials. Analysis of Microelectronic and Photonic Structures One Dimension (AMPS-1D) is a computer simulation tool for solar cell device characteristics. The first part of this study focuses on the performance and comparison of current-voltage (I-V) simulations of indium oxide (In2O3) and tin oxide (SnO2) …


Remote Chemical And Elemental Analyss By Ultra Fast Spectroscopy, Dennis R. Alexander May 2012

Remote Chemical And Elemental Analyss By Ultra Fast Spectroscopy, Dennis R. Alexander

Department of Electrical and Computer Engineering: Faculty Publications

Systems and methods are provided for monitoring materials using ultra fast laser pulses. Ultra fast laser pulses, such as femtosecond or attosecond laser pulses, are applied to the materials and laser pulses that result from interactions between the ultra fast laser pulses and the materials are collected. Spectral content of the resulting pulses is generated and presented. The elemental composition of the materials is determined using the spectral content.


Visualizing Evolution In Real-Time Method For Strain Engineering, Luis Reyes, James Winkler, Katy Kao May 2012

Visualizing Evolution In Real-Time Method For Strain Engineering, Luis Reyes, James Winkler, Katy Kao

Faculty Publications

The adaptive landscape for an industrially relevant phenotype is determined by the effects of the genetic determinants on the fitness of the microbial system. Identifying the underlying adaptive landscape for a particular phenotype of interest will greatly enhance our abilities to engineer more robust microbial strains. Visualizing evolution in real-time (VERT) is a recently developed method based on in vitro adaptive evolution that facilitates the identification of fitter mutants throughout the course of evolution. Combined with high-throughput genomic tools, VERT can greatly enhance the mapping of adaptive landscapes of industrially relevant phenotypes in microbial systems, thereby expanding our knowledge on …