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Articles 1 - 30 of 30
Full-Text Articles in Chemical Engineering
Lipids Affect The Diffusion Of Estradiol In Osteonal Bone, Nicholas Anthony Cimino
Lipids Affect The Diffusion Of Estradiol In Osteonal Bone, Nicholas Anthony Cimino
ETD Archive
In healthy osteonal bone, embedded osteocytes form an intercellular communication network through overlapping cell membrane extensions, possibly defining an overlooked and clinically relevant lipid-mediated transport pathway for nonpolar molecules. Previous techniques evaluating solute transport in cortical bone limit tissue analysis to microscale areas (less than 1 mm2) using tracers and assumptions that diminish clinical relevance, presenting the need for an improved method to evaluate solute diffusion in macroscale areas (greater than 1 mm2) of osteonal bone. A new diffusion system - constructed of glass and polytetrafluoroethylene - was designed and validated for this purpose, exhibiting minimal adsorption of solutes and …
Role Of Inflammatory Niche And Adult Cardiomyocyte Coculture On Differentiation, Matrix Synthesis, And Secretome Release By Human Bone Marrow Mesenchymal Stem Cells, Jyotsna Joshi, Chandrasekhar R. Kothapalli
Role Of Inflammatory Niche And Adult Cardiomyocyte Coculture On Differentiation, Matrix Synthesis, And Secretome Release By Human Bone Marrow Mesenchymal Stem Cells, Jyotsna Joshi, Chandrasekhar R. Kothapalli
Chemical & Biomedical Engineering Faculty Publications
Myocardial infarction (MI) causes cardiomyocyte death, provokes innate immune response, and initiates tissue remodeling. The intrinsic healing process is insufficient to replace the lost cells, or regenerate and restore the functional features of the native myocardium. Autologous bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation is being explored to offer therapeutic potential after MI. Here, we cultured human BM-MSC spheroids in three-dimensional collagenous gels for 28 days under exposure to tumor necrosis factor-alpha (+ TNFα), and coculture with adult human cardiomyocytes, or with conditioned media (CM) pooled from TNFα-stimulated adult cardiomyocytes. MSC differentiation marker (CD90, GATA4, cTnI, cTnT, Cx43, MHC, α-actin) …
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
ETD Archive
Magnetophoresis of red blood cells (RBCs) at varying partial pressures of oxygen (pO2) is hypothesized to rejuvenate stored blood to be utilized beyond the FDA regulated 42-day storage time. Magnetophoresis is a particle or cells motion induced by an applied magnetic field in a viscous media. The average magnetophoretic mobility of an oxygenated RBC is -0.126x10-6 mm3-s/kg, and a deoxygenated RBC is 3.66x10-6 mm3-s/kg, presenting magnetophoresis as a resource for RBC rejuvenation in hopes of storing it longer than 42 days. The main objective of this paper was to determine if controlling the pO2 within an RBC suspension, can singly- …
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
ETD Archive
The U.S Environmental Protection Agency (EPA) launched the Transform Tox Testing Challenge in 2016 with the goal of developing practical methods that can be integrated into conventional high-throughput screening (HTS) assays to better predict the toxicity of parent compounds and their metabolites in vivo. In response to this need and to retrofit existing HTS assays for assessing metabolism-induced toxicity of compounds, we have developed a 384-pillar plate that is complementary to traditional 384-well plates and ideally suited for culturing human cells in three dimensions (3D) at a microscale. Briefly, human embryonic kidney (HEK) 293 cells in a mixture of alginate …
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
ETD Archive
Hepatocellular carcinoma (HCC) is an invasive and aggressive cancer of the liver that arises due to chronic cirrhosis. Research into understanding HCC has focused on two-dimensional (2D) and three-dimensional (3D) technologies to simulate the liver microenvironment and use animal models to model how HCC affects the rest of the body. 3D hydrogel models are desired because they can mimic the transport behavior observed in vivo by structurally mimicking the extracellular matrix (ECM) without the ethical concerns of animal models. However, hydrogels can be toxic to cells and require optimal procedures for appropriate handling. In this study, we created 3D models …
The Role Of Synthesis Solvent In Particle Size Of Metal Organic Frameworks, Jonathan Krisak
The Role Of Synthesis Solvent In Particle Size Of Metal Organic Frameworks, Jonathan Krisak
Undergraduate Research Posters 2018
Metal organic frameworks are a class of nanoporous materials with pore sizes ranging from 0.5 to 3 nm and high surface areas (500-6000 m2/g). These materials have potential applications in industrial catalysis, separation and purification, bio-mimetics, drug delivery, semiconductors, sensors and other electronics. The aim of this study is to understand the role of solvent in control of the particle size of the final MOF product. CuBTC MOF has been used as a model MOF in this study to understand this effect. Altering the dielectric constant of solvents is a potential method of controlling the particle size. The data obtained …
Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan
Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan
Undergraduate Research Posters 2018
Microfluidic platforms have been widely regarded as defining technologies for the development of chemical and biological synthesis and analysis systems, due to benefits associated with reduced reactant consumption, increases by orders of magnitude of the surface-to-volume ratios, and greatly enhanced control over reactions variables such as temperature and pressure. However, one of the bottlenecks for their wide application is the difficulty in achieving mixing, given the typical laminar flows in these systems. In this work we implement experimentally, various strategies using geometrical features to control the fluid motion and induce stirring flows. The mixers are fabricated using soft-lithography in PDMS …
Surface Functionalization Of Pure-Chirality Carbon Nanotubes By Covalent And Noncovalent Chemistry, Fjorela Xhyliu, Niyousha Mohammad Shafie
Surface Functionalization Of Pure-Chirality Carbon Nanotubes By Covalent And Noncovalent Chemistry, Fjorela Xhyliu, Niyousha Mohammad Shafie
Undergraduate Research Posters 2018
Single-wall carbon nanotubes (SWCNTs) are one-dimensional cylindrical nanostructures with distinct electronic and optical properties. With all its atoms on the surface, SWCNTs have been widely explored for chemical modification through noncovalent and covalent chemistry, which can provide promising applications in bioimaging and sensing. Here we investigated surface functionalization of purechirality SWCNTs with various glycopolymers, surfactants, and RPMI cell culture media with and without fetal bovine serum (FBS). Raman, vis-NIR absorption, and vis-NIR fluorescence spectra of SWCNTs in various solvent environments were monitored over time. While nanotube aggregation was not observed for incubation in FBS containing RPMI for 8 hours, interactions …
Multi-Phase Waste Gasification – Reaction Engineering For Sustainable Living Environments, Kristen M. Reyes, Mason J. Lang
Multi-Phase Waste Gasification – Reaction Engineering For Sustainable Living Environments, Kristen M. Reyes, Mason J. Lang
Undergraduate Research Posters 2018
Gasification converts carbon-based (organic) materials into gaseous products typically referred to as synthetic gas. This technology is an alternative for reducing carbon footprint of energy generation as well as for waste management. This research examines Catalytic Gasification as a route to Sustainability while converting spaceflight and municipal waste into high-value products. As polyethylene (PE) makes up one of the largest portions of both municipal and space waste, this project centered its attention on the gasification of mid-density PE. We used a slurry containing middensity PE, water, and solid catalysts (ruthenium on alumina, Ru/Al2O3) in a 1:1 PE/Ru ratio. The gasification …
Treatment Of Non-Epithelial Vaginal Cells From Lysyl Oxidase Like One Knockout Mice (Loxl 1) With Nanoparticles (Nps), Priya Patel
Treatment Of Non-Epithelial Vaginal Cells From Lysyl Oxidase Like One Knockout Mice (Loxl 1) With Nanoparticles (Nps), Priya Patel
Undergraduate Research Posters 2018
Female pelvic floor dysfunction includes pelvic organ prolapse (POP) due to multiple vaginal births causing elastin strength to be reduced. Several normal functions are compromised including bladder control, fecal continence, and painful urination and many other symptoms. Currently no effective treatment is known and women seek surgical mesh implants to correct these issues which are not entirely safe nor effective. The condition of POP affects women across the world and effective treatment is sought. Varying proteins including lysyl oxidase (LOX), tissue inhibitors of metalloproteinases, and matrix metalloproteinases are involved in elastin homeostasis. In this experiment, non-epithelial vaginal cells (NEVCs) retrieved …
Characterizing Complexes Of Dna And Elastin-Like Polypeptides, Bryce Noe
Characterizing Complexes Of Dna And Elastin-Like Polypeptides, Bryce Noe
Undergraduate Research Posters 2018
Elastin-like polypeptides (ELPs) are a class of environmental responsive materials. When prepared with a protein motif that selectively binds to nucleic acids, a nucleic acid-ELP complex can be formed, conferring the responsive properties of ELP onto the nucleic acid. One possible use for such a complex is in DNA origami, where nanoscaled assemblies of DNA can be transformed into nanomachines by using the ELP as an actuator. Other possible uses include the isolation and extraction of a selected strands of genetic material, or the delivery of genetic material to a cell. Using a bacterial expression system, our lab has prepared …
Implementation Of A Reverse Staggered-Herringbone Microfluidic Mixer For High-Throughput Polymeric Nanoparticles Synthesis, Alexa Roberts
Implementation Of A Reverse Staggered-Herringbone Microfluidic Mixer For High-Throughput Polymeric Nanoparticles Synthesis, Alexa Roberts
Undergraduate Research Posters 2018
The goal of this research is to implement and optimize the operating conditions of a microfluidic mixer to synthesize polymeric nanoparticles (NPs) in a high-throughput fashion. Using a reverse staggered-herringbone microfluidic mixer that we recently designed, the effects of experimental conditions such as flowrate and reactant composition on NP characteristics were investigated and optimized. The device design allowed for physical contact between two streams of fluids – one containing poly(lactic-co-glycolic acid; PLGA) in acetonitrile and the other deionized water, to allow for efficient mixing and NP precipitation to occur. The resulting NPs were characterized using dynamic light scattering (DLS) and …
Prediction Of Metabolism-Induced Neurotoxicity On A 384pillarplate, Rushabh Patel, Pranav Joshi, Soo-Yeon Kang, Stephen Hong, Parnian Bigdelou
Prediction Of Metabolism-Induced Neurotoxicity On A 384pillarplate, Rushabh Patel, Pranav Joshi, Soo-Yeon Kang, Stephen Hong, Parnian Bigdelou
Undergraduate Research Posters 2018
Metabolism of compounds including neurotoxins primarily occurs in the liver by a variety of drug-metabolizing enzymes (DMEs) followed by a series of downstream responses. Unmodified (or parent) neurotoxins are transported into human hepatocytes through several influx transporters or via passive diffusion and undergo Phase I and Phase II biotransformation by DMEs before they are cleared. Neurotoxins and their metabolites generated from human hepatocytes could potentially lead to the toxic effects on neural stem cells (NSCs) as the reactive metabolites have potential for producing reactive oxygen species (ROS), which can lead to irreversible oxidative damage to NSCs via lipid peroxidation, DNA, …
A 3d Cancer Cell Migration Assay On A 384-Pillar Plate With Sidewalls, Nicholas Lesh, Alexander Roth, Stephen Hong, Oju Jeon, Eben Alsberg
A 3d Cancer Cell Migration Assay On A 384-Pillar Plate With Sidewalls, Nicholas Lesh, Alexander Roth, Stephen Hong, Oju Jeon, Eben Alsberg
Undergraduate Research Posters 2018
Hepatocellular carcinoma (HCC) is an aggressive liver cancer where prognosis is heavily tied to metastasis progression. Researchers look to determine the triggers for metastasis to control its spread. The goal of this project is to determine these triggers by quantifying Hep3B cell migration on a high-throughput platform. We infected Hep3B cells with lentiviruses containing mCherry to produce stable fluorescent cells. Next, we determined the stability of growth factors in oxidized, methacrylated alginate (OMA) hydrogel by binding growth factors with methacrylated heparin sulfate (MHS) before encapsulating in OMA, printing onto the 384-pillar plate with sidewalls, and quantifying growth factor release via …
Dendrite Morphology Of Pb-5.8 Sb Alloy: Gradient Freeze Ds With Cross-Section Area Change, Michael Shannon
Dendrite Morphology Of Pb-5.8 Sb Alloy: Gradient Freeze Ds With Cross-Section Area Change, Michael Shannon
Undergraduate Research Posters 2018
Directional solidification (DS) is the process of solidifying a metal alloy from one end to another resulting in aligned primary dendrites which are branched tree like features. Alignment of primary dendrites along [100] direction and their uniformity and distribution along the DS length determines the mechanical properties. These properties are especially important for single crystal turbine blade applications in modern gas turbine engines. Convection during solidification plays an important role in formation of detrimental defects, such as, misaligned grains, non-uniformity of dendrites and composition inhomogeneity. In this study the microstructural evolution during “Gradient Freeze DS process”, involving an abrupt cross-section …
Boundary Effects On The Locomotion Of Active Janus Particles, Marola W. Issa, Nicky R. Baumgartner
Boundary Effects On The Locomotion Of Active Janus Particles, Marola W. Issa, Nicky R. Baumgartner
Undergraduate Research Posters 2018
Self-propelled or “active” micrometer scale particles are capable of supplying local mechanical work, necessary for microscale cargo delivery and useful in other applications within bioimaging and sensing. Research in the last decade has focused on developing, measuring, and manipulating the locomotion mechanisms of active particles in simple environments. However, many applications will be in complex environments with nearby boundaries or variations in physiochemical cues. This poster reports the directed motion of platinum coated polystyrene particles at infinite dilution in the presence of H2O2, which acts as a fuel to drive motion. A transport mechanism called “diffusiophoresis” drives motion of the …
Idiosyncratic Drug-Induced Liver Injury (Idili): Potential Mechanisms And Predictive Assays, Alexander D. Roth, Moo-Yeal Lee
Idiosyncratic Drug-Induced Liver Injury (Idili): Potential Mechanisms And Predictive Assays, Alexander D. Roth, Moo-Yeal Lee
Chemical & Biomedical Engineering Faculty Publications
Idiosyncratic drug-induced liver injury (IDILI) is a significant source of drug recall and acute liver failure (ALF) in the United States. While current drug development processes emphasize general toxicity and drug metabolizing enzyme- (DME-) mediated toxicity, it has been challenging to develop comprehensive models for assessing complete idiosyncratic potential. In this review, we describe the enzymes and proteins that contain polymorphisms believed to contribute to IDILI, including ones that affect phase I and phase II metabolism, antioxidant enzymes, drug transporters, inflammation, and human leukocyte antigen (HLA). We then describe the various assays that have been developed to detect individual reactions …
Going Green: Experimental Adaptation Of Scenedesmus Dimorphus To Marine Conditions, Mohammed Khalil
Going Green: Experimental Adaptation Of Scenedesmus Dimorphus To Marine Conditions, Mohammed Khalil
Undergraduate Research Posters 2017
Algae has gained some interest as the need for alternative fuels becomes more pressing. Reliance on fossil fuels is causing our environment and economy harm, and is not sustainable moving forward. Lipid rich algae strains can be used in the production of biofuels, and provide an alternative fuel source. One challenge facing the prospect of algae as a fuel source is that lipid rich algae grows exclusively in freshwater. Considering the scarcity and cost to use freshwater for algae growth, interest has grown in the possibility of adapting lipid rich, freshwater algae to a seawater environment. Seawater can have up …
Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny
Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny
Undergraduate Research Posters 2017
Establishing the role that mechanics play in nerve cell (e.g. neurons) function requires experimental testing. Microfluidic based experiments are commonly used to study neuron growth and function, and studies have found mechanics to play an important role in neuron health. External loads can be applied to a microfluidic device using a motor, which presumably influences the mechanical environment of the cells. While a motor can easily apply known displacements, a “load cell” is necessary to measure corresponding forces. In an existing prototype microfluidic loading device, a load cell was integrated and verified. The manufacturer's calibration of the load cell was …
Methodological Considerations Of Electron Spin Resonance Spin Trapping Techniques For Measuring Reactive Oxygen Species Generated From Metal Oxide Nanomaterials, Min Sook Jeong, Kyeong-Nam Yu, Hyun Hoon Chung, Soo Jin Park, Ah Young Lee, Mi Ryoung Song, Myung-Haing Cho, Jun Sung Kim
Methodological Considerations Of Electron Spin Resonance Spin Trapping Techniques For Measuring Reactive Oxygen Species Generated From Metal Oxide Nanomaterials, Min Sook Jeong, Kyeong-Nam Yu, Hyun Hoon Chung, Soo Jin Park, Ah Young Lee, Mi Ryoung Song, Myung-Haing Cho, Jun Sung Kim
Chemical & Biomedical Engineering Faculty Publications
Qualitative and quantitative analyses of reactive oxygen species (ROS) generated on the surfaces of nanomaterials are important for understanding their toxicity and toxic mechanisms, which are in turn beneficial for manufacturing more biocompatible nanomaterials in many industrial fields. Electron spin resonance (ESR) is a useful tool for detecting ROS formation. However, using this technique without first considering the physicochemical properties of nanomaterials and proper conditions of the spin trapping agent (such as incubation time) may lead to misinterpretation of the resulting data. In this report, we suggest methodological considerations for ESR as pertains to magnetism, sample preparation and proper incubation …
Lipids And Collagen Matrix Restrict The Hydraulic Permeability Within The Porous Compartment Of Adult Cortical Bone, Demin Wen, Caroline Androjna, Amit Vasanji, Joanne M. Belovich, Ronald J. Midura
Lipids And Collagen Matrix Restrict The Hydraulic Permeability Within The Porous Compartment Of Adult Cortical Bone, Demin Wen, Caroline Androjna, Amit Vasanji, Joanne M. Belovich, Ronald J. Midura
Chemical & Biomedical Engineering Faculty Publications
In vivo the hydraulic permeability of cortical bone influences the transport of nutrients, waste products and signaling molecules, thus influencing the metabolic functions of osteocytes and osteoblasts. In the current study two hypotheses were tested: the presence of (1) lipids and (2) collagen matrix in the porous compartment of cortical bone restricts its permeability. Our approach was to measure the radial permeability of adult canine cortical bone before and after extracting lipids with acetone-methanol, and before and after digesting collagen with bacterial collagenase. Our results showed that the permeability of adult canine cortical bone was below 4.0 × 10 …
Anwendung Von Interferenz- Und Ir-Mikroskopie Zur Charakterisierung Und Untersuchung Des Stofftransportes In Nanoporösen Materialien, Lars Heinke, Christian Chmelik, Pavel Kortunov, Sergey Vasenkov, Douglas M. Ruthven, Dhananjai B. Shah, Jörg Kärger
Anwendung Von Interferenz- Und Ir-Mikroskopie Zur Charakterisierung Und Untersuchung Des Stofftransportes In Nanoporösen Materialien, Lars Heinke, Christian Chmelik, Pavel Kortunov, Sergey Vasenkov, Douglas M. Ruthven, Dhananjai B. Shah, Jörg Kärger
Chemical & Biomedical Engineering Faculty Publications
Die Anwendung der Interferenz-Mikroskopie bedeutet einen entscheidenden Durchbruch in der Untersuchung des Stofftransports von Gastmolekülen in nanoporösen Wirtsmaterialien. Diese Technik ermöglicht die Beobachtung der zeitaufgelösten intrakristallinen Konzentrationsprofile, die durch eine Änderung des umgebenden Gasdruckes entstehen. Dieser Ansatz wurde zur Untersuchung von Adsorptions- und Desorptionsprozessen in verschiedenen Zeolithsystemen verwendet. Die Vorteile dieser Technik, vor allem wenn sie mit Infrarotabsorptionsmessungen kombiniert wird, werden an Hand der experimentellen Resultate des Methanol-in-Ferrierit-Systems illustriert.
Procedure To Quantify Biofilm Activity In Carriers Used In Wastewater Treatment Systems, James Bolton, Archana Tummala, Chirag Kapadia, Manoj Dandamudi, Joanne M. Belovich
Procedure To Quantify Biofilm Activity In Carriers Used In Wastewater Treatment Systems, James Bolton, Archana Tummala, Chirag Kapadia, Manoj Dandamudi, Joanne M. Belovich
Chemical & Biomedical Engineering Faculty Publications
A procedure is presented for evaluating and comparing the biological activity of biofilms attached to various biofilm carriers by measurement of the glucose consumption rate. This technique allows for the economical design and selection of small particulate biofilm carriers that will maximize substrate removal when used in industrial-scale fluidized bioreactors. Methods for ensuring reproducible results are described. To support the glucose consumption rate findings, biofilm dry weights were obtained at the conclusion of activity rate experiments, and scanning electron micrographs were taken to evaluate the presence of biofilm and to view surface characteristics. Fourteen different biofilm carriers were evaluated ranging …
Blood Flow Measurements With Magnetic Resonance Phase Velocity Mapping, George P. Chatzimavroudis
Blood Flow Measurements With Magnetic Resonance Phase Velocity Mapping, George P. Chatzimavroudis
Chemical & Biomedical Engineering Faculty Publications
Magnetic resonance (MR) phase velocity mapping (PVM) is a non-invasive technique that can measure the flow velocity in any spatial direction in an imaging slice. This technique has wide application in the clinical field in quantifying blood flow, as well as in non-biomedical areas. This review describes the value and/or potential of MR PVM as a diagnostic/monitoring technique in heart valve regurgitation and in the total cavo-pulmonary connection. A single slice placed in the aortic root can accurately quantify the aortic regurgitant volume. A multi-slice control volume method has high potential for the quantification of the mitral regurgitant volume. …
Relationship Between The Extent Of Non-Viable Myocardium And Regional Left Ventricular Function In Chronic Ischemic Heart Disease, Arunark Kolipaka, George P. Chatzimavroudis, Richard D. White, Michael L. Lieber, Randolph M. Setser
Relationship Between The Extent Of Non-Viable Myocardium And Regional Left Ventricular Function In Chronic Ischemic Heart Disease, Arunark Kolipaka, George P. Chatzimavroudis, Richard D. White, Michael L. Lieber, Randolph M. Setser
Chemical & Biomedical Engineering Faculty Publications
Purpose. To define the relationship between left ventricular (LV) regional contractile function and the extent of myocardial scar in patients with chronic ischemic heart disease and multi-vessel coronary artery disease. Methods. Twenty-three patients with chronic ischemic heart disease and 5 healthy volunteers underwent magnetic resonance imaging (MRI). In patients, the relative area ( Percent Scar) and transmural extent (Transmurality) of myocardial infarction were computed from short-axis delayed enhancement images. In each image, myocardial segments were categorized based on the extent of infarction they contained, with 6 categories each for Percent Scar and Transmurality: normal, from healthy volunteers; and 0%; 1–25%, …
Fast Measurements Of Flow Through Mitral Regurgitant Orifices With Magnetic Resonance Phase Velocity Mapping, Haosen Zhang, Sandra S. Halliburton, Richard D. White, George P. Chatzimavroudis
Fast Measurements Of Flow Through Mitral Regurgitant Orifices With Magnetic Resonance Phase Velocity Mapping, Haosen Zhang, Sandra S. Halliburton, Richard D. White, George P. Chatzimavroudis
Chemical & Biomedical Engineering Faculty Publications
Magnetic-resonance (MR) phase velocity mapping (PVM) shows promise in measuring the mitral regurgitant volume. However, in its conventional nonsegmented form, MR-PVM is slow and impractical for clinical use. The aim of this study was to evaluate the accuracy of rapid, segmented k-spaceMR-PVM in quantifying the mitral regurgitant flow through a control volume (CV) method. Two segmented MR-PVM schemes, one with seven (seg-7) and one with nine (seg-9) lines per segment, were evaluated in acrylic regurgitant mitral valve models under steady and pulsatile flow. A nonsegmented (nonseg) MR-PVM acquisition was also performed for reference. The segmented acquisitions were …
Accurate Quantification Of Steady And Pulsatile Flow With Segmented K-Space Magnetic Resonance Velocimetry, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis
Accurate Quantification Of Steady And Pulsatile Flow With Segmented K-Space Magnetic Resonance Velocimetry, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis
Chemical & Biomedical Engineering Faculty Publications
Conventional non-segmented magnetic resonance phase velocity mapping (MRPVM) is an accurate but relatively slow velocimetric technique. Therefore, the aim of this study was to evaluate the accuracy of the much faster segmented k-space MRPVM in quantifying flow. The axial velocity was measured in four straight tubes (inner diameter: 5.6–26.2 mm), using a segmented MRPVM sequence with seven lines of k-space per segment. The flow rate and flow volume were accurately quantified (errorssteady (r2=0.99) and pulsatile flow (r2=0.98), respectively. The measured velocity profiles and flow rates from the segmented sequence agreed …
Ultrafast Flow Quantification With Segmented K-Space Magnetic Resonance Phase Velocity Mapping, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis
Ultrafast Flow Quantification With Segmented K-Space Magnetic Resonance Phase Velocity Mapping, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis
Chemical & Biomedical Engineering Faculty Publications
Magnetic resonance (MR) phase-velocity mapping (PVM) is routinely being used clinically to measure blood flow velocity. Conventional nonsegmented PVM is accurate but relatively slow (3–5 min per measurement). Ultrafast k-space segmented PVM offers much shorter acquisitions (on the order of seconds instead of minutes). The aim of this study was to evaluate the accuracy of segmented PVM in quantifying flow from through-plane velocity measurements. Experiments were performed using four straight tubes (inner diameter of 5.6–26.2 mm), under a variety of steady (1.7–200 ml/s) and pulsatile (6–90 ml/cycle) flow conditions. Two different segmented PVM schemes were …
Evaluation Of The Precision Of Magnetic Resonance Phase Velocity Mapping For Blood Flow Measurements, George P. Chatzimavroudis, John N. Oshinski, Robert H. Franch, Peter G. Walker, Ajit P. Yoganathan, Roderic I. Pettigrew
Evaluation Of The Precision Of Magnetic Resonance Phase Velocity Mapping For Blood Flow Measurements, George P. Chatzimavroudis, John N. Oshinski, Robert H. Franch, Peter G. Walker, Ajit P. Yoganathan, Roderic I. Pettigrew
Chemical & Biomedical Engineering Faculty Publications
Evaluating the in vivo accuracy of magnetic resonance phase velocity mapping (PVM) is not straightforward because of the absence of a validated clinical flow quantification technique. The aim of this study was to evaluate PVM by investigating its precision, both in vitro and in vivo, in a 1.5 Tesla scanner. In the former case, steady and pulsatile flow experiments were conducted using an aortic model under a variety of flow conditions (steady: 0.1–5.5 L/min; pulsatile: 10–75 mL/cycle). In the latter case, PVM measurements were taken in the ascending aorta of ten subjects, seven of which had aortic regurgitation. Each velocity …
Lntracrystalline Diffusion Of Benzene In Silicalite : Effect Of Structural Heterogeneity, Dhananjai B. Shah, Chang-Jie Guo, David T. Hayhurst
Lntracrystalline Diffusion Of Benzene In Silicalite : Effect Of Structural Heterogeneity, Dhananjai B. Shah, Chang-Jie Guo, David T. Hayhurst
Chemical & Biomedical Engineering Faculty Publications
The sorption kinetics of benzene in silicalite have been measured gravimetrically using large silicalite crystals of sizes 350 µm × 105 µm × 105 µm and 270 µm × 70 µm × 70 µm in the temperature range 283–343 K. Experiments were performed under conditions that ensured isothermal operation with intracrystalline diffusion control. An analytical expression for the Darken's correction factor (δ In P/δ In a) was derived based on the Hill–de-Boer equation and was used to determine the variation of corrected diffusivity with concentration. The transport diffusivity varied significantly with the adsorbed-phase concentration but the …