Engineering Commons^™

Neural-Electronic Inhibition Simulated With A Neuron Model Implemented In Spice, Robert B. Szlavik, Abuhanif K. Bhuiyan, Anthony Carver, Frank Jenkins

Biomedical Engineering

There have been numerous studies presented in the literature related to the simulation of the interaction between biological neurons and electronic devices. A complicating factor associated with these simulations is the algebraic complexity involved in implementation. This complication has impeded simulation of more involved neural-electronic circuitry and consequently has limited potential advancements in the integration of biological neurons with synthetic electronics. In this paper, we describe a modification to a previously proposed SPICE based Hodgkin-Huxley neuron model that demonstrates more physiologically relevant electrical behavior. We utilize this SPICE based neuron model in conjunction with an external circuit that allows for …

Least Squares Support Vector Machine Based Classification Of Abnormalities In Brain Mr Images, S. Thamarai Selvi, D. Selvathi, R. Ramkumar, Henry Selvaraj

Electrical & Computer Engineering Faculty Research

The manual interpretation of MRI slices based on visual examination by radiologist/physician may lead to missing diagnosis when a large number of MRIs are analyzed. To avoid the human error, an automated intelligent classification system is proposed. This research paper proposes an intelligent classification technique to the problem of classifying four types of brain abnormalities viz. Metastases, Meningiomas, Gliomas, and Astrocytomas. The abnormalities are classified based on Two/Three/ Four class classification using statistical and textural features. In this work, classification techniques based on Least Squares Support Vector Machine (LS-SVM) using textural features computed from the MR images of patient are …

Influence Of Pulmonary Arterial Endothelial Cells On Quinone Redox Status: Effect Of Hyperoxia-Induced Nad(P)H:Quinone Oxidoreductase 1, Marilyn P. Merker, Said H. Audi, Robert D. Bongard, Brian J. Lindemer, Gary S. Krenz

Biomedical Engineering Faculty Research and Publications

The objective of this study was to examine the impact of chronic hyperoxic exposure (95% O₂ for 48 h) on intact bovine pulmonary arterial endothelial cell redox metabolism of 2,3,5,6-tetramethyl-1,4-benzoquinone (duroquinone, DQ). DQ or durohydroquinone (DQH₂) was added to normoxic or hyperoxia-exposed cells in air-saturated medium, and the medium DQ concentrations were measured over 30 min. DQ disappeared from the medium when DQ was added and appeared in the medium when DQH₂ was added, such that after ∼15 min, a steady-state DQ concentration was approached that was ∼4.5 times lower for the hyperoxia-exposed than the normoxic …

Ischemia Reperfusion Dysfunction Changes Model-Estimated Kinetics Of Myofilament Interaction Due To Inotropic Drugs In Isolated Hearts, Samhita S. Rhodes, Amadou Ks Camara, Kristina M. Ropella, Said H. Audi, Matthias L. Riess, Paul S. Pagel, David F. Stowe

Biomedical Engineering Faculty Research and Publications

Background

The phase-space relationship between simultaneously measured myoplasmic [Ca²⁺] and isovolumetric left ventricular pressure (LVP) in guinea pig intact hearts is altered by ischemic and inotropic interventions. Our objective was to mathematically model this phase-space relationship between [Ca²⁺] and LVP with a focus on the changes in cross-bridge kinetics and myofilament Ca²⁺ sensitivity responsible for alterations in Ca²⁺-contraction coupling due to inotropic drugs in the presence and absence of ischemia reperfusion (IR) injury.

Methods

We used a four state computational model to predict LVP using experimentally measured, averaged myoplasmic [Ca²⁺] transients …

Short-Pulse Laser Propagation Through Tissue Medium For Tumor Detection, Gopalendu Pal, Kunal Mitra, Tuan Vo-Dinh

Biomedical Engineering and Sciences Faculty Publications

The objective of this paper is to perform a comprehensive experimental and numerical analysis of the short pulse laser interaction with tissue medium with the goal of tumor / cancer diagnostics. For short pulse laser source, the shape of output signal is a function of the optical properties of the medium and hence the scattered temporal optical signal helps in understanding of the medium characteristics. Initially experiments are performed on tissue phantoms imbedded with inhomogeneities in order to optimize the time-resolved optical detection scheme. Both the temporal and the spatial profiles of the scattered reflected and transmitted optical signals are …

Medical Equipment Planning And Construction Of A Interventional Neuroradiology Suite, Furqan Elahi

Theses

New York-Presbyterian Hospital is one of the most comprehensive university hospitals in the world, with leading specialists in every field of medicine. It is composed of two renowned medical centers, New York-Presbyterian Hospital/Columbia University Medical Center and New York-Presbyterian Hospital/Weill Cornell Medical Center. The hospital's strategic planning group identified the need to expand the Interventional Neuroradiology service that the hospital provides. This brought upon the need to form a committee to plan the construction of an Interventional Neuroradiology. The problem statement of this thesis is to prepare a best practices guideline from a clinical engineering perspective on constructing the three …

Impact Of Missed Beats On Heart Rate Variability Using Time-Frequency Analysis, Kilbrom T. Hailu

Theses

ECG recordings, especially during an exercise stress test, are exposed to artifacts. The source of artifacts can be due to technical problems, biological events and errors in the automatic detection. As a result missed beats, extra beats and ectopic beats can occur. In this study analysis of missed beats is performed using time-frequency analysis. Some of the patient's data had missed beats.

Fourier spectral analysis was first applied to the missed beats during the resting state. The impact of missed beats using Fourier spectral analysis is significant, especially, when the missed beats are in a row. The Fourier spectral analysis …

Non-Invasive Monitoring Of Bone Health Using Ultrasound, Nashit Jahan Meem

Theses

Bone fractures are estimated to afflict everyone at least once in his/her lifetime. Monitoring this becomes crucial especially when it comes to athletes in order for them to safely resume their regular activities as soon as possible. Technologies currently employed are either very expensive or use harmful radiation.

Ultrasound can monitor bone fractures in a non-invasive manner, as discussed in United States Patent # 5143069. Three transducers are mounted over the test specimen. A pulse generator excites the transmitting receiver. The second receiver is mounted next to the transmitter and acts as a reference receiver that displays the response across …

Qt Variability Calculation Using A Template Matching Algorithm And Power Spectral Analysis, Theodore Sami Rizkalla

Theses

ECG interval measurement and variability analysis has proven to be a useful tool in investigating autonomic nervous system function. Traditionally, the R to R interval has been the thrust of research conducted in this field. QT variability is another topic on which little research has been done.

This thesis uses an algorithm proposed by Dr. Berger, published in 2003. The algorithm stretches the template in the time domain, and composes a sum-squared error function, which is minimized to find the scaling factor for that beat. These scaling factors are compiled into an array, and an interpolated signal is generated of …

Direct Application Of The Least Action Principle To Solve (Human) Movement Dynamics Without Using Differential Equations Of Motion, Amitha Kumar

Theses

This thesis explores the numerical feasibility of solving motion 2-point boundary value problems (BVPs) by direct numerical minimization of the action without using the equations of motion (EOM) as an intermediate step. The proposed direct least action (DLA) approach using the downhill simplex method (DSM) is applied to both the single and double pendulum systems as beginning test problems. The solutions so obtained are compared to numerical solutions of the corresponding Lagrange BOM solved using a first order Euler algorithm for the same mechanical problems. The output path obtained by both of the methods essentially superimpose on each other.

Future …

Indentation Fracture Of Bovine Cortical Bone: Acoustic Emission Technique, Ashkan Safari, Ger Reilly, Brendan Mccormack

Conference Papers

Indentation cutting may result in microcracking and main crack growth which was previously reported. In this study, we recorded the AE signals produced by cracking processes during cutting on cortical bone, measuring the cutting force and correlating between load-displacement curves and AE activities.

Cutting Rate Effect On Temperature During Cortical Bone Sawing, Hamid Khalili Parsa, Ger Reilly, Brendan Mccormack

Conference Papers

When bone is cut the occurrence of thermal damage to the bone is of major concern to the surgeon. If the temperature exceeds 44°C for longer than 1 min, bone repair is impaired (Eriksson et al, 1984) and necrosis may occur. Repeated use of cutting blades may reduce the cutting efficiency (Wevers et al, 1987; Toksvig-Larsen et al, 1992). Wevers et al also found that there is a greater force required to cut cortical bone using a blunt saw compared to new one.

Vegetative Treatment Systems For Management Of Open Lot Runoff: Review Of Literature, Richard K. Koelsch, Jeffrey C. Lorimer, Kyle R. Mankin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Runoff from open lot livestock systems (beef and dairy) defined as Concentrated Animal Feeding Operations (CAFO) must be controlled by systems designed and managed to prevent the release of manure-contaminated runoff for storms equal to or less than a 25-yr, 24-h design storm. This performance standard has been attained for open lot systems with some combination of clean water diversion, settling basins, runoff collection ponds, and irrigation systems (baseline system).

An alternative approach is to rely on overland flow and infiltration into cropland with perennial forage or grasses for treatment of open lot runoff. Such vegetative systems have been researched …

A Numerical Acoustic Fluid-Structure Simulation Of Therapeutic Ultrasound Angioplasty, Graham Gavin, Finbar Dolan, M.S J. Hashmi, Garrett Mcguinness

Conference Papers

INTRODUCTION Therapeutic ultrasound angioplasty is the delivery of high amplitude ultrasonic displacements to the distal-tip of small diameter wire waveguides with the goal of disrupting atherosclerotic plaques. This is a minimally invasive procedure that may have potential' in the treatment of complicated chronic total occlusions. The disruption of plaque is due to direct contact ablation and also cavitation, pressure waves and acoustic streaming in the fluid surrounding the vibrating waveguide distal-tip [1]. Cavitation appears to play a major role and some authors have suggested that plaque ablation is only evident above the cavitation threshold [2]. Makin and Everbach [3] performed …

Predictions On Preserving Bone Mass In Knee Arthroplasty With Bisphosphonates, Jeffry S. Nyman, Juan J. Rodrigo, Scott J. Hazelwood, Oscar C. Yeh, R. Bruce Martin

Biomedical Engineering

Using a computational model of bone adaptation, we investigated the long-term ability of bisphosphonates to minimize proximal bone loss that is associated with stress shielding in the tibia after long-stemmed total knee arthroplasty (TKA). When invoking bisphosphonate effects, the remodeling activity was suppressed, and the resorption size was reduced. Compared with the untreated simulation, bisphosphonate slowed the rate of bone loss after TKA (42% reduction in bone loss at 1 year). Activating the drug 3 months before the surgery reversed bone loss associated with the reduction in such activities as walking, but it did not provide any substantial benefit in …

Osteon Interfacial Strength And Histomorphometry Of Equine Cortical Bone, Robert F. Bigley, Lanny V. Griffin, Lisa Christensen, Ryan Vandenbosch

Biomedical Engineering

The interfacial strength of secondary osteons from the diaphysis of the Thoroughbred equine third metacarpal was evaluated using the fiber pushout test. The pushout was performed on 300–500 mm sections of 4x4x15mm bone blocks machined from four anatomic regions of the cortex. Pushout strength was evaluated from proximal to distal location within the diaphysis on four osteon types classified under polarized light on adjacent histologic sections from each block. The shear strength of the interfaces were estimated from shear lag theory. Differences were found in the interfacial strength of osteons based on appearance under polarized light with bright field having …

Implantable Drug Delivery System With In-Plane Micropump, Amit A. Mhatre

Bioengineering Theses - Archive

A MEMS based Implantable Drug Delivery System (IDDS) is discussed. The heart of the system is an in-plane MEMS micropump enables us to make a compact, inexpensive system. A conceptual IDDS design is proposed. This design consists of an implantable unit which houses the micropump, electronic and power circuitry. This implantable unit is connected to a subcutaneous port via a silicone catheter. The subcutaneous port acts as a refillable reservoir. This leads to a reduction in unit volume and makes the system customizable. The IDDS pumps drug into surrounding tissue with the help of a MEMS-based micropump. The force generated …

An Unsupervised Fluoroscopic Analysis Of Knee Joint Kinematics, Charles Scott, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

Knowledge of the three dimensional positions of bones at a joint as a function of time is required to accurately model joint kinematics. 3-D bone geometry data from a static computer tomography (CT) images can be combined with time sequence information from 2-D video fluoroscopy images to produce 3-D position data over time. The process involves creating virtual X-rays from the CT image through digitally reconstructed radiograph (DRR) projections. Historically, the process of matching the 3-D and 2-D data has required human interaction. We have eliminated the need for manual initialization using a Monte Carlo technique with a variable search …

Controlled Braking Scheme For A Wheeled Walking Aid, Eugene Coyle, Aidan O'Dwyer, Eileen Young, Kevin Sullivan, A. Toner

Conference papers

A wheeled walking aid with an embedded controlled braking system is described. The frame of the prototype is based on combining features of standard available wheeled walking aids. A braking scheme has been designed using hydraulic disc brakes to facilitate accurate and sensitive controlled stopping of the walker by the user, and if called upon, by automatic action. Braking force is modulated via a linear actuating stepping motor. A microcontroller is used for control of both stepper movement and for supervisory control. An encoder is used to supervise walker movement in terms of time, distance and speed.

Nanoelectropulse-Driven Membrane Perturbation And Small Molecule Permeabilization, P. Thomas Vernier, Yinghua Sun, Martin A. Gundersen

Bioelectrics Publications

Background
Nanosecond, megavolt-per-meter pulsed electric fields scramble membrane phospholipids, release intracellular calcium, and induce apoptosis. Flow cytometric and fluorescence microscopy evidence has associated phospholipid rearrangement directly with nanoelectropulse exposure and supports the hypothesis that the potential that develops across the lipid bilayer during an electric pulse drives phosphatidylserine (PS) externalization.

Results
In this work we extend observations of cells exposed to electric pulses with 30 ns and 7 ns durations to still narrower pulse widths, and we find that even 3 ns pulses are sufficient to produce responses similar to those reported previously. We show here that in contrast to …

Plasma Membrane Voltage Changes During Nanosecond Pulsed Electric Field Exposure, W. Frey, R. O. Price, P. F. Blackmore, R. P. Joshi, R. Nuccitelli, S. J. Beebe, K. H. Schoenbach, J. F. Kolb

Bioelectrics Publications

The change in the membrane potential of Jurkat cells in response to nanosecond pulsed electric fields was studied for pulses with a duration of 60 ns and maximum field strengths of similar to 100 kV/cm (100 V/cell diameter). Membranes of Jurkat cells were stained with a fast voltage-sensitive dye, ANNINE-6, which has a subnanosecond voltage response time. A temporal resolution of 5 ns was achieved by the excitation of this dye with a tunable laser pulse. The laser pulse was synchronized with the applied electric field to record images at times before, during, and after exposure. When exposing the Jurkat …

A Numerical Acoustic Fluid-Structure Model Of A Therapeutic Ultrasound Angioplasty Device, Graham Gavin, M.S. J. Hashmi, Finbar Dolan, Garrett Mcguinness

Conference Papers

Ultrasonic angioplasty involves the use of ultrasonic vibrations delivered to the distal-tip of small diameter wire waveguides and is an emerging technology the may have potential use in the treatment of complicated atherosclerotic plaques during cardiovascular surgery. Complicated plaques, including chronic total occlusions and calcified lesions, seriously reduce success rates during standard intervention involving guidewire access, followed by balloon dilation or stent delivery. The large amplitude (0-150 μm) wire waveguide distal-tip displacements in the low-frequency ultrasonic (18-45 kHz) range have been shown to disrupt plaque material by direct contact ablation and cavitation, acoustic streaming and pressure wave components in adjacent …

Development Of A Software Application To Extract The Features Of Normal Respiratory Sounds From The Lungs And The Trachea, Ranjani Sabarinathan

Theses and Dissertations

Auscultation has been widely regarded as one of the most important noninvasive diagnostic tools for clinical diagnosis of the respiratory tract. The purpose of this thesis was to develop a software application capable of extracting the key features of respiratory sound signals from the lungs and trachea of healthy persons. The efficacy of the program was evaluated by the verification of the important features of the sound signals from the left and right lungs and the trachea such as 1) right and left lung symmetry and 2) dissimilarity between the trachea and both lungs. The program was developed in LabView …

Intracellular Signaling Networks In The Immune Response: Pathways Activated By Interleukin-2 And-4 Receptors And Their Roles In T Cell Proliferation, Kristen K. Comfort

Chemical and Materials Engineering Faculty Publications

Cells sense and respond to chemical and physical stimuli through signal transduction pathways, which mediate cell proliferation, differentiation, migration, and survival. The cytokines interleukin-2 (IL-2) and interleukin-4 (IL-4) are key regulators of the adaptive immune system, particularly influencing the clonal expansion and differentiation of T cells. At least in culture, both synergistic and antagonistic effects of IL-2 and -4 co-stimulation have been reported; the antagonism, when observed, is thought to arise from the utilization of a common subunit shared by IL-2 and IL-4 receptors. We have sought to characterize IL-2 and IL-4 signaling at the level of intracellular pathways activated …

Osteonal Effects On Elastic Modulus And Fatigue Life In Equine Bone, V. A. Gibson, S. M. Stover, J. C. Gibeling, S. J. Hazelwood, R. B. Martin

Biomedical Engineering

We hypothesized that recently formed, incompletely mineralized, and thus, relatively deformable osteons in the equine third metacarpus enhance in vitro load-controlled fatigue life in two ways. Macroscopically, there is a compliance effect, because reduced tissue elastic modulus diminishes the stress required to reach a given strain. Microscopically, there is a cement line effect, in which new osteons and their cement lines more effectively serve as barriers to crack propagation. We studied 18 4×10×100 mm beams from the medial, lateral, and dorsal cortices of metacarpal bones from 6 thoroughbred racehorses. Following load-controlled fatigue testing to fracture in 4 point bending, a …

Determination Of The Mechanical Properties Of Electrospun Gelatin Based On Polymer Concentration And Fiber Alignment, Leander Taylor Iii

Theses and Dissertations

The process of electrospinning has given the field of tissue engineering insight into many aspects of tissue engineered scaffolds, including how factors such as fiber diameter and porosity are affected by polymer concentration. However, the affects of fiber alignment upon the material properties of electrospun scaffolds remains unclear. The purpose of this study is to determine how the material properties of electrospun gelatin scaffolds are affected by changes in fiber alignment and starting gelatin concentration. Gelatin scaffolds, with starting concentrations of 80, 100, and 130mg/m1, were electrospun onto a target mandrel rotating at various speeds. Samples of each scaffold were …

Scaffold Permeability As A Means To Determine Fiber Diameter And Pore Size Of Electrospun Fibrinogen, Scott Allen Sell

Theses and Dissertations

The purpose of this study was to construct a flowmeter that could accurately measure the hydraulic permeability of electrospun fibrinogen scaffolds, providing insight into the transport properties of electrospun scaffolds while making the measurement of their topographical features (fiber and pore size) more accurate. Three different concentrations of fibrinogen were used (100, 120, and 150mg/ml) to create scaffolds with three different fiber diameters and pore sizes. The fiber diameters and pore sizes of the electrospun scaffolds were analyzed through scanning electron microscopy and image analysis software. The permeability of each scaffold was measured and used to calculate permeability-based fiber diameters …

Reproducing Published Results From In Silico Computer Models Of The Acute Inflammatory Response To Severe Sepsis, Wayne W. Wakeland, Joe Fusion, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

Recent studies describe computer simulation models of the acute or systemic inflammatory response (AIR or SIR) to severe sepsis, a condition that can lead to multiple organ failure and death. One study used an agent-based model, while the other used differential equations (DEs) to simulate a randomized clinical trial. Both studies obtained results similar to the actual results from a successful clinical drug trial of severe sepsis, suggesting that in silico (simulated) randomized clinical trials may be used to design more effective in vivo clinical trials.

Recombinant Human Bmp-7 Effectively Prevents Non-Union In Both Young And Old Rats, David J. Hak, Takeshi Makino, Takahiro Niikura, Scott J. Hazelwood, Shane Curtiss, A. Hari Reddi

Biomedical Engineering

The purpose of this study was to evaluate the influence of age on the effectiveness of rhBMP-7 treatment in a fracture with severe periosteal damage that is known to result in non-union formation. Closed stabilized femur fractures were produced in 3-month-old and 18-month-old rats. The fracture site was exposed and 2 mm of the periosteum cauterized circumferentially to impair normal fracture healing. The cauterized fracture site was immediately treated with either 100 mg rhBMP-7 (BMP-7 group), or with 25 xL of vehicle alone (control group). Fracture healing was evaluated with radiographs taken at 3 and 6 weeks. Animals were sacrificed …

Postharvest Treatment To Control Codling Moth In Fresh Apples Using Water Assisted Radio Frequency Heating, Shaojin Wang, Sohan Birla, J. D. Hansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Apples destined for export to Japan and South Korea are currently disinfested for codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), using methyl bromide fumigation. Restrictions and limitations imposed on the uses of methyl bromide have increased interest in developing alternative non-chemical quarantine treatments. It is imperative that the treatment is effective against codling moth yet maintains the quality of treated apples. The present study explored the application of radio frequency (RF) energy in conjunction with conventional hot water treatment to develop feasible heat treatments. Treatment parameters were selected based on minimum time–temperature conditions required for 100% mortality of fifth-instar codling …