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An Analysis Of Eliminating Electroosmotic Flow In A Microfluidic Pdms Chip, Cecile D. Redington

Master's Theses

The goal of this project is to eliminate electroosmotic flow (EOF) in a microfluidic chip. EOF is a naturally occurring phenomenon at the fluid-surface interface in microfluidic chips when an electric field is applied across the fluid. When isoelectric focusing (IEF) is carried out to separate proteins based on their surface charge, the analytes must remain in the separation chamber, and not migrate to adjacent features in the microfluidic chip, which happens with EOF.

For this project, a microfluidic chip was designed and commissioned to be photolithographically transferred onto a Si wafer. A PDMS component was then casted on the …

Distribution And Accumulation Of Trichloroethylene And Trichloroacetic Acid In Hybrid Poplars, Lucas Odom, Joel Gerard Burken, Lee Newman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hybrid Poplar Trees Are Known to Take Up Trichloroethylene (TCE) into above Ground Tissues, Where It Degrades into the Metabolites Trichloroacetic Acid (TCAA), Dichloroacetic Acid, and Trichloroethanol and Where Parent Chlorinated Solvents Volatilize to the Atmosphere. based on This Knowledge, Numerous Phytoremediation Applications Have Been Implemented for TCE and Other Chlorinated Solvents. Sampling of Plant Tissues Has Proven Effective for Phytoforensic and Phytoscreening Applications in Assessing Sites and Evaluating the Efficacy of Phytoremediation. However, Little is Known About the Appropriate Exposure Times and Sampling Locations Required to Obtain an Accurate Assessment of TCE and Metabolites. in This Study, Hybrid Poplars …

Automated Methods To Determine Electrospun Fiber Alignment And Diameter Using The Radon Transform, Nicholas J. Schaub, Sean J. Kirkpatrick, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Recent evidence demonstrates the ability to change cell function by altering the physical properties of electro spun scaffolds, but many studies still do not characterize electro spun fiber alignment and diameter. To aid in the reporting of these crucial properties, we demonstrate two methods of quantifying electro spun fiber alignment with one method capable of determining electro spun fiber diameter. The first method assesses fiber alignment in a scanning electron microscopy image using the Radon Transform (RT) to calculate the entropy of the fibers in the image. The RT entropy method was more sensitive than a commonly used Fast Fourier …

Force Sensing Surgical Scissor Blades Using Fibre Bragg Grating Sensors, Dean Callaghan

Doctoral

This thesis considers the development and analysis of unique sensorised surgical scissor blades for application in minimally invasive robotic surgery (MIRS). The lack of haptic (force and tactile) feedback to the user is currently an unresolved issue with modern MIRS systems. This thesis presents details on smart sensing scissor blades which enable the measurement of instrument-tissue interaction forces for the purpose of force reflection and tissue property identification. A review of current literature established that there exists a need for small compact, biocompatible, sterilisable and robust sensors which meet the demands of current MIRS instruments. Therefore, the sensorised blades exploit …

Physicochemical Characterization Of Safranal-Β-Cyclodextrin Inclusion Complexes Prepared By Supercritical Carbon Dioxide And Conventional Methods., Sanaz Abbaszadegan

Theses

Saffron (Crocus sativus. Linn) has attracted much attention over the last decade because it has a large number of potent and biologically active compounds such as crocin, crocetin, picrocrocin and safranal. Researchers have shown that safranal has high antioxidant and cytotoxicity activities against several types of tumour cells (e.g., hepatocellular carcinoma) both in-vitro and in-vivo. However, the low aqueous solubility of safranal prevents using it as a therapeutic or preventive agent.

β-cyclodextrin (β-CD) inclusion complexes are being used in pharmaceutical applications to alter physicochemical properties (e.g., solubility, volatility, stability, chemical reactivity, and bio-availability) of poorly water soluble drugs. Thus the …

Atomic Layer Deposited Highly Dispersed Platinum Nanoparticles Supported On Non-Functionalized Multiwalled Carbon Nanotubes For The Hydrogenation Of Xylose To Xylitol, Xinhua Liang, Chengjun Jiang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Highly dispersed platinum nanoparticles were deposited on gram quantities of non-functionalized multiwalled carbon nanotubes (MWCNTs) by atomic layer deposition (ALD) in a fluidized bed reactor at 300°C. (Methylcyclopentadienyl) trimethylplatinum and oxygen were used as precursors. The results of TEM analysis showed that ∼1.3 nm Pt nanoparticles were highly dispersed on non-functionalized MWCNTs. The porous structures of MWCNTs did not change with the deposition of Pt nanoparticles. For comparison, the commercial 3 wt.% Pt/C catalyst was also characterized. The ALD-prepared Pt/MWCNT was used for the hydrogenation of xylose to xylitol. The ALD-prepared Pt/MWCNT showed the best catalytic performance with 100 % …

Ex Vivo Diffusion Tensor Imaging Of Spinal Cord Injury In Rats Of Varying Degrees Of Severity, Michael Jirjis, Shekar N. Kurpad, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

The aim of this study was to characterize magnetic resonance diffusion tensor imaging (DTI) in proximal regions of the spinal cord following a thoracic spinal cord injury (SCI). Sprague–Dawley rats (n = 40) were administered a control, mild, moderate, or severe contusion injury at the T8 vertebral level. Six direction diffusion weighted images (DWIs) were collected ex vivo along the length of the spinal cord, with an echo/repetition time of 31.6 ms/14 sec and b = 500 sec/mm2. Diffusion metrics were correlated to hindlimb motor function. Significant differences were found for whole cord region of interest (ROI) drawings for fractional …

Outer Retinal Structure In Best Vitelliform Macular Dystrophy, David B. Kay, Megan E. Land, Robert F. Cooper, Adam M. Dubis, Pooja Godara, Alfredo Dubra, Joseph Carroll, Kimberly E. Stepien

Biomedical Engineering Faculty Research and Publications

Importance Demonstrating the utility of adaptive optics scanning light ophthalmoscopy (AOSLO) to assess outer retinal structure in Best vitelliform macular dystrophy (BVMD).

Objective To characterize outer retinal structure in BVMD using spectral-domain optical coherence tomography (SD-OCT) and AOSLO.

Design, Setting, and Participants Prospective, observational case series. Four symptomatic members of a family with BVMD with known BEST1 mutation were recruited at the Advanced Ocular Imaging Program research lab at the Medical College of Wisconsin Eye Institute, Milwaukee.

Intervention Thickness of 2 outer retinal layers corresponding to photoreceptor inner and outer segments was measured using SD-OCT. Photoreceptor mosaic AOSLO images within …

Batch And Continuous Production Of Stable Dense Suspensions Of Drug Nanoparticles In A Wet Stirred Media Mill, Afolawemi Afolabi

Dissertations

One way to improve the bioavailability of poorly water-soluble drugs is to reduce particle size of drug crystals down to nanoscale via wet stirred media milling. An increase in total surface area per mass loading of the drug and specific surface area as well as reduced external mass transfer resistance allow a faster dissolution of the poorly-water soluble drug from nanocrystals. To prevent aggregation of nanoparticles, polymers and surfactants are dissolved in water acting as stabilizers via adsorption onto the drug crystals.

In the last two decades, ample experimental data were generated in the area of wet stirred media milling …

Characterization Of Neural Ion Regulation Dysfunction During Insult And Evaluation Of Micro-Opioid Receptor Activation During Simulated Ischemia In The Pre-Botzinger Complex, Kyle F. Dobiszewski

Dissertations

The health and vitality of brain tissue is dependent upon the cells' abilities to maintain ionic homeostasis across their plasma membranes. Even slight alterations in intracellular or extracellular can have a devastating effect on excitability and neural vitality. This thesis investigates several concepts related to ion flux. First, it investigates how ion flux affects characterization of brain tissue by dielectric spectroscopy and what can be done to overcome that effect. Second, it investigates how ion flux can be used to describe the state of health of the tissue. Finally, it investigates if pharmacological intervention can attenuate some of the deleterious …

Pressure Swing Membrane Absorption Process For Separation Of Low Temperature Post-Shift Reactor Syngas, John Chau

Dissertations

This thesis is concerned with a cyclic pressure swing membrane absorption process (PSMAB) for separation of the feed gas mixture containing —40% CO₂-He balance using pure ionic liquid, 1-butyl-3-methylimidazolium dicyanamide ([bmim][DCA]), and its solution containing poly(amidoamine) (PAMAM) dendrimer Gen 0 primarily with a dry feed gas. An advanced pressure swing membrane absorption process is developed to produce purified He as a surrogate for H₂ at a high pressure from simulated low- temperature shifted syngas for different membrane modules. The PSMAB process also simultaneously produces a highly purified CO₂ stream containing bulk of the CO₂ in …

Pegleg Crutch, Levi Leishman, Darrel Zeltner

Journal of Undergraduate Research

The progress of a cheap, simple and practical substitute for the common crutch for us has had many design improvements and successes in this year. We were able to meet with medical, educational, and engineering professionals who were all able to input their criticisms and advice. We have decided on a final design that is not the best design for use, but the best when considering cost. See figure 1 for a visual of the final design.

Advanced Treatment Of Dyeing Wastewater For Reuse By Electrochemical Oxidation, Fei-Xiang Chen, Chu-Yin Yang, Ming-Ming Zhou, Jia-De Wang

Journal of Electrochemistry

In response to the characteristics of dye wastewater, the electrochemical oxidation of effluents from the biochemical process of dyeing wastewater was studied in the electrochemical reactor using PbO₂/Ti electrode as the anode and stainless steel plate as the cathode. The results revealed that the electrochemical oxidation could simultaneously remove the Chemical Oxygen Demand (COD), ammonia and chromaticity. At the residence time of 60 min and current density of 10 mA·cm^-2, the COD, ammonia, chromaticity, concentration of chloride ion and pH values could meet the water standards for “the reuse of urban recycling water-water quality standard for …

Electrochemically Switched Ion Exchange Properties Of Pani-Snp Composite Films In Wastewater Containing Ni2+ And Cd2+, Yan-Ting Feng, Jun-Qiang Xiao, Xiao-Gang Hao, Xu-Li Ma, Zhong-De Wang, Nian-Chen Han

Journal of Electrochemistry

Electroactive PANI-SnP composite films were prepared by drop-coating method on Pt electrodes and investigated as electrochemically switched ion exchange (ESIX) materials for the separation of Cd²⁺ from aqueous solutions. The composition and morphology of the composite film were characterized by Fourier transform infrared spectrometer (FTIR) and scanning electron microscope (SEM). In solutions containing 0.1 mol·L^-1 Ni(NO₃)₂ and Cd(NO₃)₂, cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM) were used to investigate the electrochemical behavior and ion-exchange mechanism of PANI-SnP composite film. The elementary composition of PANI-SnP composite films in both oxidation …

Synthetic Polymeric Carbohydrates Recognized Toxoplasma Gondii Tachyzoites And Induced Early Phagocytosis By Macrophages, Souzan Hussain Eassa

Theses and Dissertations

Toxoplasmosis is a parasitic disease caused by the intracellular protozoan Toxoplasma gondii your words (T. gondii your words) that affects most types of warm-blooded vertebrate cells. Up to one third of the humans population in the world is chronically infected by this parasite. Human and animals at risk for toxoplasmosis include fetuses, newborns, and immunologically impaired patients. To date, there is no vaccine available and no drug has a successful effective against chronic form of toxoplasmosis. Recent Toxoplasma your words diagnostic methods showed high false positive results and cannot detect the parasite in the early infection stage. Early diagnosis of …

Electrochemical Behavior And Content Determination Of Paeonol At Poly Sudan Ⅲ Modified Electrode, Yan-Jie Zheng, Ai-Lin Liu, Yun Lei, Xin-Hua Lin

Journal of Electrochemistry

The poly SudanⅢ modified electrode was characterized by electrochemical impedance spectroscopy（EIS）and cyclic voltammetry (CV), while the electrochemical behavior of paeonol was studied by cyclic voltammetry (CV). The result shows that the poly Sudan Ⅲ modified electrode exhibits excellent electrocatalytic effect on the oxidation of paeonol. The peak currents of differential pulse voltammetry are linear to the paeonol concentrations over the range of 3.0*10^-7 ~ 2.2*10^-5 mol·L^-1. The detection limit has been estimated to be 5.0*10^-8 mol·L^-1. This method can be used for determination of paeonol content in real sample with satisfactory results.

Development Of The In Vivo Multicolor Photoacoustic Flow Cytometer, Mustafa Sarimollaoglu

Theses and Dissertations

Flow cytometry is a powerful tool for analysis of cells in artificial flow. This highly accurate technology, using multicolor fluorescent probes and lasers with different wavelengths, provides fast multiparameter quantification of the biological properties of cells. Invasive extraction of cells from an organism, however, leads to changes in cell properties and low sensitivity, and prevents studying cells in their native environment. Challenges to advances in in vivo flow cytometry include fluorescent probe toxicity, strong background, and number of colors, as well as assessment of small vessels. To overcome these limitations, photoacoustic flow cytometry (PAFC) was introduced. PAFC is based on …

Study On The Selection Mechanism Of Opening Targeted Ship-Borne Containers Carrying Dangerous Goods, Yuheng Lu

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Maritime Environmental Influence Of Large-Scale Tanker On The Water Area Of Tianjin Port, Hanhui Guo

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Antenna Diversity For Personal Communications Transceivers, Bruce M. Green, Dr. Michael A. Jensen

Journal of Undergraduate Research

The presence of human tissue near the antenna of a portable cellular phone reduces its range of reception and transmission. This research investigates the feasibility of antenna diversity (more than one antenna on a handset) as a means of combating the loss of received signal power to a cellular phone antenna due to the biological tissues of the operator. The Finite Difference Time Domain (FDTD) method provides simulations of two antenna designs that accurately models both the antenna and tissue of the operator.

Strengthening The Pathway To Stem Research Leadership At Hope College, Catherine Mader

Faculty Presentations

Over the past 20 years, awards from the Howard Hughes Medical Institute have supported Hope's efforts to conduct STEM research and to prepare students to pursue careers as STEM researchers. The current program is building upon prior successes to create a deliberate pathway for students as they enter Hope as novices, build STEM Researcher skills through coursework and summer research and eventually become student leaders in STEM Research groups.

Protein Structure Validation And Identification From Unassigned Residual Dipolar Coupling Data Using 2d-Pdpa, Arjang Fahim, Rishi Mukhopadhyay, Ryan Yandle, James H. Prestegard, Homayoun Valafar

Faculty Publications

More than 90% of protein structures submitted to the PDB each year are homologous to some previously characterized protein structure. The extensive resources that are required for structural characterization of proteins can be justified for the 10% of the novel structures, but not for the remaining 90%. This report presents the 2D-PDPA method, which utilizes unassigned residual dipolar coupling in order to address the economics of structure determination of routine proteins by reducing the data acquisition and processing time. 2D-PDPA has been demonstrated to successfully identify the correct structure of an array of proteins that range from 46 to 445 …

High-Speed, Three-Dimensional Quantification Of Ladybug (Hippodamia Convergens) Flapping Wing Kinematics During Takeoff, Ryan B. George, Dr. Scott L. Thomson

Journal of Undergraduate Research

Ladybug wing and body kinematics during takeoff is explored using high-speed stereoscopic imaging. Recordings of the specimens during flight are acquired at a rate of 3000 frames per second. A direct linear transformation algorithm is performed using custom implementation in Matlab to quantify positions of selected locations on the body, forewings (elytra), and hindwings. Design and setup of instrumentation and analysis procedures are explained. Flapping frequency is reported. Significant motion of the elytra and other findings are presented and their applications are discussed.

Optical Fiber To Integrated Waveguides: Bridging The Gap, Mallory Phillips, Dr. Aaron R. Hawkins

Journal of Undergraduate Research

Optoelectronics are made on the surface of a thin substrate of semiconductor material by attaching light-sensitive polymers to the surface, then removing patterns generated in the polymer. Waveguides can be made on the same substrate to interface directly with optoelectronics. They are made from raised channels running along the substrates surface and guide light through total internal reflection, much like optical fibers [1]. Optical fibers are used for internet and cable connections, in order for information to be successfully used, that information must make a transition from the optical fiber to integrated waveguides [2]. The engineering challenge associated with this …

Few-View Single Photon Emission Computed Tomography (Spect) Reconstruction Based On A Blurred Piecewise Constant Object Model, Paul Arthur Wolf, Jakob S. Jørgensen, Taly Gilat Schmidt, Emil Y. Sidky

Biomedical Engineering Faculty Research and Publications

A sparsity-exploiting algorithm intended for few-view single photon emission computed tomography (SPECT) reconstruction is proposed and characterized. The algorithm models the object as piecewise constant subject to a blurring operation. To validate that the algorithm closely approximates the true object in the noiseless case, projection data were generated from an object assuming this model and using the system matrix. Monte Carlo simulations were performed to provide more realistic data of a phantom with varying smoothness across the field of view and a cardiac phantom. Reconstructions were performed across a sweep of two primary design parameters. The results demonstrate that the …

The Application Of The Genetic Adaptive Neural Network In Landslide Disaster Assessment, Jing-Wen Chen, Yung-Sheng Chue, Yie-Ruey Chen

Journal of Marine Science and Technology–Taiwan

This study applied the Genetic Adaptive Neural Network (GANN) structure to satellite image classification and the assessment of landslide disaster. First, the study conducted quantitative analysis of the various factors of slope development and natural environmental hazards in some parts of the catchment areas of the Laonong River in Southern Taiwan. Meanwhile, using the weighting ratios of various disaster causing factors inferred from the best structure of GANN, this study explored the degree of slope land disturbance. Then, this study incorporated the relationship between rainfall and landslides to draw a landslide potential map using the discriminant analysis approach combined with …

Model Simulation Of Asian Dust And Iron Depositions Over The East Asian Marginal Seas, Fujung Tsai

Journal of Marine Science and Technology–Taiwan

This study applies a dust model to investigate Asian dust and iron depositions on the East Asian marginal sea during the months of the northeasterly monsoon from November to May, when dust events are often observed. Simulated dry and wet depositions of dust are compared with measurements obtained from Taipei, Taiwan. According to the model simulation, higher concentrations of atmospheric dust occur from March to May over East Asia, resulting in greater dry and wet deposition fluxes of dust and iron within these months than other months. The monthly averaged dry and wet deposition fluxes of iron are 0.6 and …

Determination Of Mortar Saturation Methods Based On Mri Scanning Image, Hsiang-Wei Chiang, Ran Huang

Journal of Marine Science and Technology–Taiwan

Magnetic resonance imaging (MRI) is widely used in the medical field and among one of the greatest inventions in recent years. In MRI images, the bright zone denotes signals that are generated by water in the specimen. However, solid cement-based materials lack water. Therefore, developing a method to achieve optimal saturation for cement-based materials is crucial for MRI scanning. In this study, the immersion, boiling, and vacuum methods were used to achieve saturation for various mortar specimens with w/c ratios of 0.45, 0.55, and 0.65. By comparing MRI images and absorption test results, we found that the vacuum method tends …

Generating High Purity Embryonic Stem Cell-Derived Cell Populations For Transplantation Following Spinal Cord Injury, Dylan A. Mccreedy

McKelvey School of Engineering Graduate Student Theses & Dissertations

Embryonic stem cells hold great potential for cell replacement strategies in the central nervous system. Pre-differentiation into various neural cell types can help generate tissue-specific cell populations that can replace cells and tissue lost due to do injury or disease. A small number of undifferentiated pluripotent stem cells persist in most transplant populations even after pre-differentiation. Given the right environment, i.e. biomaterial scaffolds, these cells can lead to tumor formation thereby eliminating any potential therapeutic benefit. This dissertation focused on the development of high purity embryonic stem cell-derived cell populations devoid of pluripotent stem cells for transplantation into the central …

Improving Radiotherapy Targeting For Cancer Treatment Through Space And Time, Camille Noel

McKelvey School of Engineering Graduate Student Theses & Dissertations

Radiotherapy is a common medical treatment in which lethal doses of ionizing radiation are preferentially delivered to cancerous tumors. In external beam radiotherapy, radiation is delivered by a remote source which sits several feet from the patient's surface. Although great effort is taken in properly aligning the target to the path of the radiation beam, positional uncertainties and other errors can compromise targeting accuracy. Such errors can lead to a failure in treating the target, and inflict significant toxicity to healthy tissues which are inadvertently exposed high radiation doses.

Tracking the movement of targeted anatomy between and during treatment fractions …