Biomedical Engineering and Bioengineering Commons^™

Monitoring Of Mesenchymal Based Constructs Using Magnetic Resonance Elastography, Evan T. Curtis

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Evaluating the functionality of an engineered material lies in the proper characterization of its material and functional properties. In the treatment of musculoskeletal disorders, engineered bone or fat tissue must behave as an adequate replacement else failure of the material could result in discomfort and further surgical procedures. A significant material characteristic that reflects tissue development is the mechanical properties (i.e. shear strength and viscosity). Shear strength and viscosity provide an indication of how efficient the material is in dissipating energy. Energy dissipation occurs naturally in many tissues including fat and can prevent damage to deeper tissues. Many of the …

Adaptive Real-Time Decoding Of Brain Signals For Long-Term Control Of A Neuro-Prosthetic Device, Tushar Ashok Dharampal

Master's Theses (2009 -)

Changes in the statistical properties of neural signals recorded at the brain machine interface (BMI) pose significant challenges for accurate long-term control of prostheses interfaced directly with the brain by continuously altering the relationship between neural responses and desired action. In this thesis, we develop and test an adaptive decoding algorithm that can recover from changes in the statistical properties of neural signals within minutes. The adaptive decoding algorithm uses a Kalman filter as part of a dual-filter design to continuously optimize the relationship between the observed neural responses and the desired action of the prosthesis. Performance of the algorithm …

Examining The Relationships Among Injury Outcomes, Velocity And Grip Strength During Dynamic Platform Perturbation, Braden Cripe

Master's Theses (2009 -)

Studies examining the relationship between inputs and outputs for simulated models of dynamically perturbed horizontal platforms are scarce. Most of these scenarios include a standing operator with upper extremity grip, oftentimes subjected to lateral impulses, which may lead to occupant injury. While the detailed study of these collision scenarios is sparse, the prevalence of their application is great.

This thesis aims to identify how two input parameters, velocity change (ÄV) and grip strength, affect injury assessment reference values (IARVs). This is accomplished by using Mathematical Dynamic Modeling (MADYMO) software to simulate the scenarios defined by those inputs. In the simulation, …

Role Of Tendon Vibration In Multijoint Reflex Coupling In The Hemiparetic Arm Post Stroke, Bani Gadhoke

Master's Theses (2009 -)

Post stroke hemiparesis causes reflex coupling in multiple muscles of the arm, leading to atypical movements that hamper motor control. In particular, people post-stroke can become unstable while holding the arm at the end of a planar motion. Recently, we have found that tendon vibration of the wrist flexors improves the stability of the arm during a hold task. The objective of the current study was to identify the effects of vibration applied to the wrist flexors on the biceps and triceps stretch reflexes, generated using a tendon tapper. In people post-stroke, tendon tap perturbations of the biceps and triceps …

Methods For Detecting High-Frequency Oscillations In Ongoing Brain Signals: Application To The Determination Of Epileptic Seizure Onset Zones, Chiran Dilip Doshi

Master's Theses (2009 -)

Epilepsy is a neurological disorder with varied expression. Patients with focal onset seizures that are resistant to medications can benefit from ablative surgery. However, localization of the seizure onset zone (SOZ) and characterization of propagation to secondary areas can be challenging. The present study aimed at developing the appropriate signal processing methodology to detect bursts of interictal high-frequency oscillations (HFOs), as a possible signature of the SOZ, in patients with drug-resistant partial epilepsy. Additionally, invasive interictal and ictal intracranial electroencephalography (iEEG) data and non-invasive electromagnetic source imaging with magnetoencephalography (MEG) data from three subjects were analyzed. We developed a novel …

Tools For Creating Wide-Field Views Of The Human Retina Using Optical Coherence Tomography, Ashavini M. Pavaskar

Master's Theses (2009 -)

Optical Coherence Tomography (OCT) has allowed in-vivo viewing of details of retinal layers like never before. With the development of spectral domain OCT (SD-OCT) details of nearly 2µm axial resolution and higher imaging speed have been reported. Nevertheless, a single volume scan of the retina is typically restricted to 6mm x 6mm in size. Having a larger field of view of the retina will definitely enhance the clinical utility of the OCT.

A tool was developed for creating wide-field thickness maps of the retina by combining the use of already available tools like i2k Retina (DualAlign, LLC, Clifton Park, NY) …

Modeling And Computational Framework For The Specification And Simulation Of Large-Scale Spiking Neural Networks, David James Herzfeld

Master's Theses (2009 -)

Recurrently connected neural networks, in which synaptic connections between neurons can form directed cycles, have been used extensively in the literature to describe various neurophysiological phenomena, such as coordinate transformations during sensorimotor integration. Due to the directed cycles that can exist in recurrent networks, there is no well-known way to a priori specify synaptic weights to elicit neuron spiking responses to stimuli based on available neurophysiology. Using a common mean field assumption, that synaptic inputs are uncorrelated for sufficiently large populations of neurons, we show that the connection topology and a neuron's response characteristics can be decoupled. This assumption allows …

Development Of An Experimental Model To Quantify Lumbar Spine Kinematics During Military Seat Ejection, Steven George Storvik

Master's Theses (2009 -)

The initial phase of a military ejection sequence exerts substantial axial loads on the spinal column. Eccentric inertial loading on the thoracolumbar spine can lead to injury. Most serious injuries due to ejection are in the form of a vertebral fracture, most commonly occurring at the thoracolumbar junction. The objective of the current study was to understand characteristics of a military seat ejection by employing an experimental model designed to simulate the boost or in-rail phase. The model incorporates realistic boundary conditions and is capable of quantifying metrics associated with injury tolerance such as applied accelerations and resultant loads and …

Detection Of Specific Biological Antigens Using Ac Electrochemical Impedance Spectroscopy, Darrel Angelo Mazzari

Dissertations (1934 -)

When certain antigens are present in our environment, a rapid, on-site, accurate, selective, and repeatable detection method can be invaluable in preventing illness or saving lives. Rapid detection of these antigens is important to avert spreading infections.

Currently, capturing a sample and sending it to a laboratory can take weeks to get results, which can be much too long. Conventional sensing methodologies include various electrical measurements as capacitive, potentiometric, piezoelectric, surface plasmon resonance (SPR), and quartz crystal microbalance (QCM). Of particular power and interest is Alternating Current (AC) Electrochemical Impedance Spectroscopy (EIS) which provides for the characterization of the electrical …

A Silicon Nanoparticle-Based Polymeric Nano-Composite Material For Glucose Sensing, Qiang Liu, Munir H. Nayfeh, Siu-Tung Yau

Electrical and Computer Engineering Faculty Publications

A novel non-enzyme glucose sensing material has been prepared by incorporating ultrasmall (1–3 nm) silicon nanoparticles in polyaniline, a conducting polymer, as a nano-composite material (NCM). When deposited on electrodes, the composite material with three-dimensional loading of the nanoparticles showed a significantly enhanced amperometric response to glucose, compared to the nanoparticles deposited on bare electrodes and electrodes immobilized with the enzyme, glucose oxidase. The linear range of the glucose response of NCM electrodes covered both the hypo- and hyper-glycaemic glucose levels. The sensitivity of the NCM electrodes was 2.5 μA cm⁻² mM⁻¹. The NCM electrodes’ selectivity for …

Differential Responses Of Targeted Lung Redox Enzymes To Rat Exposure To 60 Or 85% Oxygen, Zhuohui Gan, David L. Roerig, Anne V. Clough, Said H. Audi

Biomedical Engineering Faculty Research and Publications

Rat exposure to 60% O₂ (hyper-60) or 85% O₂ (hyper-85) for 7 days confers susceptibility or tolerance, respectively, of the otherwise lethal effects of exposure to 100% O₂. The objective of this study was to determine whether activities of the antioxidant cytosolic enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1) and mitochondrial complex III are differentially altered in hyper-60 and hyper-85 lungs. Duroquinone (DQ), an NQO1 substrate, or its hydroquinone (DQH₂), a complex III substrate, was infused into the arterial inflow of isolated, perfused lungs, and the venous efflux rates of DQH₂ and DQ were measured. …

Noninvasive Imaging Of The Human Rod Photoreceptor Mosaic Using A Confocal Adaptive Optics Scanning Ophthalmoscope, Alfredo Dubra, Yusufu N. Sulai, Jennifer L. Norris, Robert F. Cooper, Adam M. Dubis, David R. Williams, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

The rod photoreceptors are implicated in a number of devastating retinal diseases. However, routine imaging of these cells has remained elusive, even with the advent of adaptive optics imaging. Here, we present the first in vivo images of the contiguous rod photoreceptor mosaic in nine healthy human subjects. The images were collected with three different confocal adaptive optics scanning ophthalmoscopes at two different institutions, using 680 and 775 nm superluminescent diodes for illumination. Estimates of photoreceptor density and rod:cone ratios in the 5°–15° retinal eccentricity range are consistent with histological findings, confirming our ability to resolve the rod mosaic by …

Brain-Related Chronic Pain Disorder Diagnosis And Assessment Method, Jeffrey Hargrove

Mechanical Engineering Patents

A method for diagnosing and assessing a brain-related chronic pain disorder. The method includes assessing a subject's brain function, deterrnining the probability that a subject is suffering from chronic pain as a result of an abnormal brain function condition by obtaining a quantitative assessment of the subject's brain function, and making a statistical comparison between the subject's quantitative brain function assessment and either a database of quantitative assessments of the brain functions of normal, healthy individuals, or a database of quantitative assessments of the brain functions of individuals known to have been suffering from chronic pain as a result of …

Comparing Fbg And Pcf Force Sensors In A Laparoscopic Smart Surgical Scissor Instrument, Dean Callaghan, Ginu Rajan, Mark Mcgrath, Eugene Coyle, Yuliya Semenova, Gerald Farrell

Conference Papers

This paper presents a sensorized laparoscopic surgical scissor instrument using both a fiber Bragg grating (FBG) and a tapered photonic crystal fiber (PCF) as force sensors. The sensors are located on the blades for the detection of interaction forces generated between the instrument and tissue during cutting. The force sensitivity of each sensorized blade is examined. Results show that the scissor blade-PCF sensor arrangement outperforms the blade with the FBG during static loading calibration experimentation. Moreover, experiments show that the PCF based arrangement is less sensitive to temperature effects than its FBG counterpart. This negates the need for additional temperature …

The 4+1 Program And Distance Learning Meeting Objectives And Outcomes, Daniel W. Walsh, Lanny Griffin, Robert S. Crockett

Biomedical Engineering

Graduate engineering education is a key to the maintenance of U.S. competitiveness in the world market. The world has been an extremely dynamic engine during the last fifty years, and we have witnessed a dramatic change in the world order. The change has been evolutionary in many cases, but events in Eastern Europe, the Middle East and the erstwhile Soviet Union are only slightly less cataclysmic than the Second World War. In a world where strength is measured in terms of the financial resource, the technological ability and the intellectual capability of a populace Japan, China, India and the EEC …

Review Of Gasoline, Diesel, And Ethanol Biofuels From Grasses And Plants, By Ram B. Gupta And Ayhan Demirbas., Adam J. Liska

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A new book on the production of biofuels by Gupta and Demirbas provides technical insight into the conversion processes that could provide a range of domestic fuels from plant materials to substitute for foreign oil. It focuses primarily on conversion processes for production of cellulosic ethanol, Fischer-Tropsch diesel, pyrolysis bio-oil, and hydrothermal biocrude from biomass resources, as well as "first-generation" grain ethanol and biodiesel from vegetable oil. In addition to a detailed summary of these chemical processes, the book provides a briefer treatment of related matters such as biofuel policy, economics, and environmental issues.

Surgical Cutting And Ablation By Energy Based Devices: Principles And Applications, Garrett Mcguinness, Joseph A. Mcgeough, Graham Gavin, Brendan O'Daly

Conference Papers

Advances in ultrasound, radiofrequency, and water jet systems are facilitating their increased use in new medical ablation or cutting applications in fields as diverse as cardiology, orthopaedics, ophthalmology, dermatology, oncology and neurosurgery. These methods involve controlled alteration or destruction of tissues via the application of thermal, electrical or kinetic energy. This market segment is characterised by advanced devices capable of heating or cooling tissue from -200°C to 400°C, or inducing vibrations of up to 60 kHz to cause tissue damage. The medical conditions targeted primarily pertain to chronic and age-related diseases, but elective and cosmetic procedures are also addressed. Medical …

The Effect Of Adding Organic Polymers To Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. Coughlan, N. M. Cummins, A. W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

To conclude, the addition of polymers to GPCs resulted in little change to the Tw and Ts, however the compressive strength was found to decrease slightly. ASAP tests revealed that the cements may undergo some structural changes as a result of these additions. In the future perhaps the addition of organic polymers suspended in the liquid phase as part of the cement may yield improved results in this type of study. © 2011 IEEE.

Aluminium-Free Glass Polyalkenoate Spinal Cements, A. W. Wren, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Addition of Yitanium increased the Wt & St and the sf strength of these cements compared to the control (BT 101). © 2011 IEEE.

An Argument For The Importance Of Material Property Characterization Of Hydrogels, J. M. Zuidema, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrogels are being fabricated for use in many tissue engineering applications. In order to advance the field, material properties must be characterized to determine the most desirable attributes. The data presented shows the importance of both surface charge and mechanical properties on dorsal root ganglia neurite extension. © 2011 IEEE.