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Biomedical Engineering and Bioengineering

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Articles 9421 - 9450 of 11448

Full-Text Articles in Engineering

Synchronization And Media Exchange In Large-Scale Caenorhabditis Elegans Cultures, Jason D. Brown Dec 2009

Synchronization And Media Exchange In Large-Scale Caenorhabditis Elegans Cultures, Jason D. Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The nematode Caenorhabditis elegans is a model organism for understanding sensory molecules of multicellular organisms. Ovulating hermaphrodites produce putative pheromone(s) that cause male attraction. Because pheromones are produced in such small quantities, adult conditioned-media from large-scale synchronous culture is necessary to analyze these pheromones. Current protocols for culture synchronization have volume constraints that limit large-scale synchronous cultures and current methodology for adult conditioned-media production is impractical.

Modification of Tangential Flow Filtration (TFF) systems was investigated for use as a method to increase the volume limits of bleach egg harvest for C. elegans culture synchronization. Also, an adult retention device built …


Mechanical Structures Resisting Anterior Instability In A Computational Glenohumeral Joint Model, Kevin Elmore Nov 2009

Mechanical Structures Resisting Anterior Instability In A Computational Glenohumeral Joint Model, Kevin Elmore

Theses and Dissertations

The glenohumeral joint is the most dislocated joint in the body due to the lack of bony constraints and dependence on soft tissue, primarily muscles and ligaments, to stabilize the joint. The goal of this study was to develop a computational model of the glenohumeral joint whereby joint behavior was dictated by articular contact, ligamentous constraints, muscle loading, and external perturbations. Validation of this computational model was achieved by comparing predicted results from the model to the results of a cadaveric experiment in which the relative contribution of muscles and ligaments to anterior joint stability was examined. The results showed …


Pegylation Of Niosomes, John A. Elliott Nov 2009

Pegylation Of Niosomes, John A. Elliott

USF Tampa Graduate Theses and Dissertations

The research presented in this dissertation describes the creation and characterization of a novel antibody-vesicle conjugate modified with polyethylene glycol (PEG) that possesses enhanced binding to and uptake by inflammation-activated endothelial cells with improved storage stability and longer shelf-life and potential reduction in immunogenic potential compared to previous designs.

Targeted drug delivery provides an effective means of delivering therapeutic concentrations of a drug to the site or organ of action. The drug is delivered using a niosome, a vesicle with an aqueous core and a bilayer membrane composed of non-ionic surfactants and cholesterol. Antibodies that recognize specific cell antigens are …


Fabrication Of Spherical Cao-Sro-Zno-Sio2 Particles By Sol-Gel Processing, Ill Yong Kim, Mark R. Towler, Anthony Wren, Chikara Ohtsuki Nov 2009

Fabrication Of Spherical Cao-Sro-Zno-Sio2 Particles By Sol-Gel Processing, Ill Yong Kim, Mark R. Towler, Anthony Wren, Chikara Ohtsuki

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study was concerned with the fabrication of ceramic CaO-SrO-ZnO-SiO2 spherical particles, which are novel candidates for the glass phase in glass polyalkenoate cements (GPCs). GPCs made from these glasses have potential as bone cements because, unlike conventional GPCs, they do not contain aluminum ions, which inhibit the calcification of hydroxyapatite in the body. The glass phase of GPCs require a controllable glass morphology and particle size distribution. Sol-gel processing can potentially be used to fabricate homogenous ceramic particles with controlled morphology. However, a thorough study on preparation conditions of spherical CaO-SrO-ZnO-SiO2 particles by sol-gel processing has, to …


Characterisation And Mechanical Testing Of Hydrothermally Treated Ha/Zro2 Composites, D. J. Curran, T. J. Fleming, G. Kawachi, C. Ohtsuki, Mark R. Towler Nov 2009

Characterisation And Mechanical Testing Of Hydrothermally Treated Ha/Zro2 Composites, D. J. Curran, T. J. Fleming, G. Kawachi, C. Ohtsuki, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrothermal treatment is traditionally employed to improve the sinterability of powder compacts by reducing porosity and increasing apparent density. The effect of hydrothermal treatment on green powder compacts has been assessed in order to better understand how treatment may affect the sinter ability of the bodies. Laboratory synthesized nano sized hydroxyapatite (HA) and a commercial zirconia (ZrO2) powder have been ball milled together to create composite mixtures containing 0-5 wt% ZrO2 loadings. Disc shaped bodies have been formed using uniaxial and subsequent isostatic pressure. The resultant coherent samples were subjected to hydrothermal treatment at either 120 or …


Analysis Of Γ-Irradiated Synthetic Bone Grafts By ²⁹Si Mas-Nmr Spectroscopy, Calorimetry And Xrd, D. Boyd, S. Murphy, Mark R. Towler, A. W. Wren, S. Hayakawa Nov 2009

Analysis Of Γ-Irradiated Synthetic Bone Grafts By ²⁹Si Mas-Nmr Spectroscopy, Calorimetry And Xrd, D. Boyd, S. Murphy, Mark R. Towler, A. W. Wren, S. Hayakawa

Chemical and Biochemical Engineering Faculty Research & Creative Works

Ca-Sr-Zn-Si glasses have demonstrated excellent biocompatibility both in vitro using the MTT assay with L929 mouse fibroblast cells, and in vivo using healthy and ovariectomized female Wistar rats. However, the biological evaluation of the materials was performed on glass granules that were autoclaved, rather than γ-irradiated; the sterilisation procedure required prior to implantation of these materials in the human body. Given the fact that when a glass is exposed to ionizing radiation changes in its physical properties can take place, it is imperative to determine whether the structure of such glasses will be altered as a result of exposure to …


Extraction And Characterization Of Natural Cellulose Fibers From Common Milkweed Stems, Narendra Reddy, Yiqi Yang Nov 2009

Extraction And Characterization Of Natural Cellulose Fibers From Common Milkweed Stems, Narendra Reddy, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Natural cellulose fibers with cellulose content, strength, and elongation higher than that of milkweed floss and between that of cotton and linen have been obtained from the stems of common milkweed plants. Although milkweed floss is a unique natural cellulose fiber with low density, the short length and low elongation make milkweed floss unsuitable as a textile fiber. The possibility of using the stems of milkweed plant as a source for natural cellulose fibers was explored in this research. Natural cellulose fibers extracted from milkweed stems have been characterized for their composition, structure, and properties. Fibers obtained from milkweed stems …


A Rapid Prototyping Method For Constructing A Complex Three-Dimensional Substrate, Kathryn Jacoba Hart Nov 2009

A Rapid Prototyping Method For Constructing A Complex Three-Dimensional Substrate, Kathryn Jacoba Hart

Master's Theses

Cell culturing on three-dimensional structures has increased the possibilities in tissue engineering and bioreactor research. These structures enable cells to differentiate, proliferate, mobilize, and function in a conformation that more accurately mimics in vivo conditions. Computer generated models aid in development and rapid alteration of three-dimensional cell substrates, defining their internal structure as well as their external morphology. The rapid transition from substrate design to a viable culture is imperative to quickly advance research in biomedical and tissue engineering applications.

The aim of this thesis is to investigate the feasibility of a rapid prototyping process by selectively cross-linking and assembling …


On Coupling A Lumped Parameter Heart Model And A Three-Dimensional Finite Element Aorta Model, H. J. Kim, Irene E. Vignon-Clementel, C. A. Figueroa, John F. Ladisa, K. E. Jansen, Jeffrey A. Feinstein, Charles A. Taylor Nov 2009

On Coupling A Lumped Parameter Heart Model And A Three-Dimensional Finite Element Aorta Model, H. J. Kim, Irene E. Vignon-Clementel, C. A. Figueroa, John F. Ladisa, K. E. Jansen, Jeffrey A. Feinstein, Charles A. Taylor

Biomedical Engineering Faculty Research and Publications

Aortic flow and pressure result from the interactions between the heart and arterial system. In this work, we considered these interactions by utilizing a lumped parameter heart model as an inflow boundary condition for three-dimensional finite element simulations of aortic blood flow and vessel wall dynamics. The ventricular pressure–volume behavior of the lumped parameter heart model is approximated using a time varying elastance function scaled from a normalized elastance function. When the aortic valve is open, the coupled multidomain method is used to strongly couple the lumped parameter heart model and three-dimensional arterial models and compute ventricular volume, ventricular pressure, …


Comparison Of Cumulative Planimetry Versus Manual Dissection To Assess Experimental Infarct Size In Isolated Hearts, Matthias L. Riess, Samhita S. Rhodes, David F. Stowe, Mohammed Aldakkak, Amadou K.S. Camara Nov 2009

Comparison Of Cumulative Planimetry Versus Manual Dissection To Assess Experimental Infarct Size In Isolated Hearts, Matthias L. Riess, Samhita S. Rhodes, David F. Stowe, Mohammed Aldakkak, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

Introduction

Infarct size (IS) is an important variable to estimate cardiac ischemia/reperfusion injury in animal models. Triphenyltetrazolium chloride (TTC) stains viable cells red while leaving infarcted cells unstained. To quantify IS, infarcted and non-infarcted tissue is often manually dissected and weighed (IS-DW). An alternative is to measure infarcted areas by cumulative planimetry (IS-CP).

Methods

We prospectively compared these two methods in 141 Langendorff-prepared guinea pig hearts (1.44 ± 0.02 g) that were part of different studies on mechanisms of cardioprotection. Hearts were perfused with Krebs–Ringer's and subjected to 30 min global ischemia after various cardioprotective treatments. Two hours after reperfusion …


Exploiting Multiple Sensory Modalities In Brain-Machine Interfaces, Aaron J. Suminski, Dennis C. Tkach, Nicholas G. Hatsopoulos Nov 2009

Exploiting Multiple Sensory Modalities In Brain-Machine Interfaces, Aaron J. Suminski, Dennis C. Tkach, Nicholas G. Hatsopoulos

Biomedical Engineering Faculty Research and Publications

Recent improvements in cortically-controlled brain-machine interfaces (BMIs) have raised hopes that such technologies may improve the quality of life of severely motor-disabled patients. However, current generation BMIs do not perform up to their potential due to the neglect of the full range of sensory feedback in their strategies for training and control. Here we confirm that neurons in the primary motor cortex (MI) encode sensory information and demonstrate a significant heterogeneity in their responses with respect to the type of sensory modality available to the subject about a reaching task. We further show using mutual information and directional tuning analyses …


Development Of A Mechanical System For Osteon Isolation, S. Ranglin, D. Das, A. Mingo, O. Ukinamemen, Gaffar Gailani, S. Cowin, L. Cardoso Oct 2009

Development Of A Mechanical System For Osteon Isolation, S. Ranglin, D. Das, A. Mingo, O. Ukinamemen, Gaffar Gailani, S. Cowin, L. Cardoso

Publications and Research

Osteons are small semi cylindrical hard tissues that exist in long bones of humans and some animals. Their diameter is in the range of 250 – 300 micrometers approximately. They contain the osteocytes which plays a role in bone mechanotransduction. The boundary that surrounds the osteon from outside is called the cement line. In a summer research project supported by CUNY-LSAMP a group of four students and three professors worked full summer to develop a system that can isolate the osteons thus a mechanical testing could be performed (stress relaxation test) to determine their poroelastic properties. Two sets of osteons …


The Design And Validation Of A Computational Rigid Body Model Of The Elbow., Edward Spratley Oct 2009

The Design And Validation Of A Computational Rigid Body Model Of The Elbow., Edward Spratley

Theses and Dissertations

The use of computational modeling is an effective and inexpensive way to predict the response of complex systems to various perturbations. However, not until the early 1990s had this technology been used to predict the behavior of physiological systems, specifically the human skeletal system. To that end, a computational model of the human elbow joint was developed using computed topography (CT) scans of cadaveric donor tissue, as well as the commercially available software package SolidWorks™. The kinematic function of the joint model was then defined through 3D reconstructions of the osteoarticular surfaces and various soft-tissue constraints. The model was validated …


Simple Agarose-Chitosan Gel Composite System For Enhanced Neuronal Growth In Three Dimensions, Zheng Cao, Ryan J. Gilbert, Wei He Oct 2009

Simple Agarose-Chitosan Gel Composite System For Enhanced Neuronal Growth In Three Dimensions, Zheng Cao, Ryan J. Gilbert, Wei He

Chemical and Biochemical Engineering Faculty Research & Creative Works

A simplified approach to increase neuronal attachment on an agarose hydrogel was proposed by blending agarose with another biocompatible polysaccharide, chitosan. The stiffness of the agarose gel was maintained despite the inclusion of chitosan, as determined by rheological tests. The structure of the blended hydrogels was characterized using light microscopy and scanning electron microscopy. An in vitro cell study revealed that the blends promoted neuron adhesion. The concentration of chitosan in the hydrogel had great influence on the morphology of neurons. An optimum range of chitosan concentration in agarose gel, to enhance neural cell attachment and differentiation, was identified based …


Beyond Biobricks: Synthesizing Synergistic Biochemical Systems From The Bottom-Up, Mark A. Bedau Oct 2009

Beyond Biobricks: Synthesizing Synergistic Biochemical Systems From The Bottom-Up, Mark A. Bedau

Systems Science Friday Noon Seminar Series

Engineers who attempt to discover and optimize the behavior of complex biochemical systems face a dauntingly difficult task. This is especially true if the systems are governed by multiple qualitative and quantitative variables that have non-linear response functions and that interact synergistically. The synthetic biology community has responded to this difficulty by promoting the use of "standard biological parts" called "BioBricks", which are supposed to make biology into traditional engineering and enable engineers to "program living organisms in the same way a computer scientists can program a computer". But the BioBricks research program faces daunting hurdles, because the nonlinearity and …


Material Properties Are Related To Stress Fracture Callus And Porosity Of Cortical Bone Tissue At Affected And Unaffected Sites, Rachel C. Entwistle,, Sara C. Sammons, Robert F. Bigley, Scott J. Hazelwood, David P. Fyhrie, Jeffery C. Gibeling, Susan M. Stover Oct 2009

Material Properties Are Related To Stress Fracture Callus And Porosity Of Cortical Bone Tissue At Affected And Unaffected Sites, Rachel C. Entwistle,, Sara C. Sammons, Robert F. Bigley, Scott J. Hazelwood, David P. Fyhrie, Jeffery C. Gibeling, Susan M. Stover

Biomedical Engineering

Stress fractures are overuse injuries of bone that affect elite athletes and military recruits. One response of cortical bone to stress fracture is to lay down periosteal callus. The objectives of this study were to determine if material properties are different among bones with different stages of stress fracture callus, at both a callus site and at a distal site. Cortical specimens were mechanically tested to determine their stress–strain response. Material property differences were examined using nonparametric and regression analyses. At the callus site, material properties were low during the earliest stages of callus, higher with increasing callus maturity, but …


Improvement Of Eeg Based Brain Computer Interface By Application Of Tripolar Electrodes And Independent Component Analysis, Hongbao Cao Oct 2009

Improvement Of Eeg Based Brain Computer Interface By Application Of Tripolar Electrodes And Independent Component Analysis, Hongbao Cao

Doctoral Dissertations

For persons with severe disabilities, a brain computer interface (BCI) may be a viable means of communication, with scalp-recorded electroencephalogram (EEG) being the most common signal employed in the operation of a BCI. Various electrode configurations can be used for EEG recording, one of which was a set of concentric rings that was referred to as a Laplacian electrode. It has been shown that Lapalacian EEG could improve classification in EEG recognition, but the complete advantages of this configuration have not been established.

This project included two parts. First, a modeling study was performed using Independent Component Analysis (ICA) to …


The Uqam Mummy – The Use Of Non-Destructive Imaging To Reconstruct An Ancient Osteobiography And To Document Modern Malfeasance, Andrew J. Nelson, Andrew D. Wade, R. Hibbert, B. Macdonald, M. Donaldson, R. Chatelain, N. Nguyen, V. Lywood, G. Gibson, M. Trumpour, S. N. Friedman, P. V. Granton, J. Morgan, David W. Holdsworth, I. A. Cunningham Oct 2009

The Uqam Mummy – The Use Of Non-Destructive Imaging To Reconstruct An Ancient Osteobiography And To Document Modern Malfeasance, Andrew J. Nelson, Andrew D. Wade, R. Hibbert, B. Macdonald, M. Donaldson, R. Chatelain, N. Nguyen, V. Lywood, G. Gibson, M. Trumpour, S. N. Friedman, P. V. Granton, J. Morgan, David W. Holdsworth, I. A. Cunningham

Anthropology Presentations

An Egyptian mummy and her coffin dating to the 26th Dynasty were donated to the École de Beaux Arts in Montreal in 1927. This mummy has been in the collection of the Université du Québec à Montréal since 1967. Inscriptions on the elaborate coffin identify the individual as Hetep-Bastet. In 1969, the mummy was attacked by a protester, who caused extensive damage. The mummy was scanned once over a decade ago. However, computed tomography (CT) technology has advanced a great deal since that time, and some conclusions reached were somewhat suspect (e.g. that she suffered from a large dental abscess …


The Effect Of Glass Synthesis Route On Mechanical And Physical Properties Of Resultant Glass Ionomer Cements, A. Wren, O. M. Clarkin, F. R. Laffir, C. Ohtsuki, I. Y. Kim, Mark R. Towler Oct 2009

The Effect Of Glass Synthesis Route On Mechanical And Physical Properties Of Resultant Glass Ionomer Cements, A. Wren, O. M. Clarkin, F. R. Laffir, C. Ohtsuki, I. Y. Kim, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass ionomer cements (GICs) have potential orthopaedic applications. Solgel processing is reported as having advantages over the traditional melt-quench route for synthesizing the glass phase of GICs, including far lower processing temperatures and higher levels of glass purity and homogeneity. This work investigates a novel glass formulation, BT 101 (0.48 SiO2-0.36 ZnO-0.12 CaO-0.04 SrO) produced by both the melt-quench and the solgel route. The glass phase was characterized by X-ray diffraction (XRD) to determine whether the material was amorphous and differential thermal analysis (DTA) to measure the glass transition temperature (Tg). Particle size analysis (PSA) was …


Focusing Electromagnetic Radiation In Dielectric Media, Mark A. Migliaccio Jr. Oct 2009

Focusing Electromagnetic Radiation In Dielectric Media, Mark A. Migliaccio Jr.

Electrical & Computer Engineering Theses & Dissertations

Bioelectrics and microwave imaging requires an ultra-wideband (UWB) antenna to deliver intense, short electromagnetic pulses into biological targets for the purpose of therapy and imaging. Two antennas with different focal distances, predicted by a two­ dimensional model, have been designed for focusing electromagnetic radiation in the near field.

Focusing is achieved through the use of prolate spheroidal reflector antennas with a conical wave launcher submerged in water. For an ultra-wideband feed signal, with a rise time of 200 picoseconds, the maximum electric field was found to be close to the edge of the reflector, a result that differs from the …


Ekg Tracking For Augmented Standardized Patient Virtual Pathology Stethoscope Heart Auscultation, Sujith Surendran Oct 2009

Ekg Tracking For Augmented Standardized Patient Virtual Pathology Stethoscope Heart Auscultation, Sujith Surendran

Electrical & Computer Engineering Theses & Dissertations

In recent years, a lot of research has focused on improving the clinical skills of medical students and medical practitioners using standardized patients. Standardized patients (SP's) are used by the medical students and physicians in place of mannequins for a more realistic experience. SP's are real people trained to simulate specific illnesses and conditions to a high degree of accuracy which makes it difficult for the medical students to distinguish them from real patients. This research will enhance the capabilities of the standardized patients by providing a non-invasive, natural, harmless and realistic appearing tracking method for placing virtual pathologies using …


Compliance Calibration For Fracture Testing Of Anisotropic Biological Materials, J. A. Creel, S. M. Stover, R. B. Martin, D. P. Fyhrie, S. J. Hazelwood, J. C. Gibeling Oct 2009

Compliance Calibration For Fracture Testing Of Anisotropic Biological Materials, J. A. Creel, S. M. Stover, R. B. Martin, D. P. Fyhrie, S. J. Hazelwood, J. C. Gibeling

Biomedical Engineering

The compliance technique has been used to monitor crack length during fracture and fatigue testing of materials. Difficulties arise when this technique is applied to anisotropic biological materials such as bone. In this tutorial, two different methods of analyzing compliance calibration data are described: the standard ASTM method and a new approach developed by the authors specifically for anisotropic materials. An example is given showing how data from equine cortical bone can be analyzed. In this example, calibration tests were conducted on thirty-six three point bend specimens machined from the middiaphysis of six pairs of equine third metacarpal bones. Cracks …


A Biomechanical Comparison Of Locked Plate Fixation With Percutaneous Insertion Capability Versus The Angled Blade Plate In A Subtrochanteric Fracture Gap Model, Brett D. Crist, Afshin Khalafi, Scott J. Hazelwood, Mark A. Lee Oct 2009

A Biomechanical Comparison Of Locked Plate Fixation With Percutaneous Insertion Capability Versus The Angled Blade Plate In A Subtrochanteric Fracture Gap Model, Brett D. Crist, Afshin Khalafi, Scott J. Hazelwood, Mark A. Lee

Biomedical Engineering

Objectives: The angled blade plate has been the historical standard in fixed-angle extramedullary subtrochanteric femur fracture fixation, but it requires an extensile lateral approach to the femur. Little formal evaluation exists for specifically designed percutaneous extramedullary implants. The purpose of this study was to compare 3 locked plating constructs, all with percutaneous insertion capability, with the standard 95-degree angled blade plate to determine whether specifically designed fixed-angle extramedullary implants for subtrochanteric femur fractures were biomechanically comparable to the angled blade plate.

Methods: Forty composite adult femurs were divided into 4 equal groups. The constructs evaluated included a 95-degree angled blade …


Statistical Hypothesis Testing For Postreconstructed And Postregistered Medical Images, Eugene Demidenko Oct 2009

Statistical Hypothesis Testing For Postreconstructed And Postregistered Medical Images, Eugene Demidenko

Dartmouth Scholarship

Postreconstructed and postregistered medical images are typically treated as the raw data, implicitly assuming that those operations are error free. We question this assumption and explore how the precision of reconstruction and affine registration can be assessed by the image covariance matrix and confidence interval, called the confidence eigenimage, using a statistical model-based approach. Various hypotheses may be tested after image reconstruction and registration using classical statistical hypothesis testing vehicles: Is there a statistically significant difference between images? Does the intensity at a specific location or area of interest belong to the “normal” range? Is there a tumor? Does the …


Modulation Of Mitochondrial Bioenergetics In The Isolated Guinea Pig Beating Heart By Potassium And Lidocaine Cardioplegia: Implications For Cardioprotection, Mohammed Aldakkak, David F. Stowe, Edward J. Lesnefsky, James S. Heisner, Qun Chen, Amadou K.S. Camara Oct 2009

Modulation Of Mitochondrial Bioenergetics In The Isolated Guinea Pig Beating Heart By Potassium And Lidocaine Cardioplegia: Implications For Cardioprotection, Mohammed Aldakkak, David F. Stowe, Edward J. Lesnefsky, James S. Heisner, Qun Chen, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

Mitochondria are damaged by cardiac ischemia/reperfusion (I/R) injury but can contribute to cardioprotection. We tested if hyperkalemic cardioplegia (CP) and lidocaine (LID) differently modulate mitochondrial (m) bioenergetics and protect hearts against I/R injury. Guinea pig hearts (n = 71) were perfused with Krebs Ringer's solution before perfusion for 1 minute just before ischemia with either CP (16 mM K+) or LID (1 mM) or Krebs Ringer's (control, 4 mM K+). The 1-minute perfusion period assured treatment during ischemia but not on reperfusion. Cardiac function, NADH, FAD, m[Ca2+], and superoxide (reactive oxygen species) were assessed at baseline, during the 1-minute perfusion, …


Monte Carlo Model Of Light Propagation In Tissues And The Effects Of Phase Changes On The Light Intensity, Rakesh Choula Oct 2009

Monte Carlo Model Of Light Propagation In Tissues And The Effects Of Phase Changes On The Light Intensity, Rakesh Choula

Electrical & Computer Engineering Theses & Dissertations

Lasers, due to their unique properties, have a wide range of applications in the medical field. For accurate laser treatments that focus on bio-tissues, prior knowledge of the amount of laser power, spot size and its irradiation time are necessary. In order to predict the effects of lasers on tissues and their bio-effects, a first necessary step is the creation of a model that can predict the temperature distributions within the tissue following laser excitation. This involves modeling light propagation through the tissue with inclusion of internal scattering, and assessment of the energy deposited by the incoming photons. The next …


Towards Supervised Autonomous Task Completion Using An In Vivo Surgical Robot, Jason J. Dumpert Oct 2009

Towards Supervised Autonomous Task Completion Using An In Vivo Surgical Robot, Jason J. Dumpert

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Laparoscopy is a minimally invasive alternative to traditional abdominal surgery. Unlike traditional surgery, a laparoscopic procedure can be completed using small incisions. The use of these small incision results in reduced pain to the patient, shorter recovery times, and less trauma to skin, muscle and other tissues. However, these benefits to the patient are offset by the increased difficulty to the surgeon performing the procedure. These difficulties include reduced dexterity, reduced perception, and longer procedure times. The use of small in vivo robotic devices in minimally invasive surgery is one possible solution to these problems. The movement of these devices …


Regression Analysis Of Fracture Toughness For Secondary Osteons Located In Human Cortical Bone, Chase A. Fetzer Oct 2009

Regression Analysis Of Fracture Toughness For Secondary Osteons Located In Human Cortical Bone, Chase A. Fetzer

Master's Theses

An experiment was carried out in order to locate and quantify osteon types within a sample of cortical bone taken from a human tibia. This was done using a microscope-camera assembly and the BioQuant computer software. The results of this were correlated with a previous experiment’s results on fracture toughness so that an analysis could be run on the data in order to determine the factors that most affect the value of fracture toughness of this cortical bone. Results were examined closely and the analysis repeated until the author was satisfied that the best possible model for fracture toughness had …


Flexor Reflex Decreases During Sympathetic Stimulation In Chronic Human Spinal Cord Injury, Mark Kevin Garrison, Brian D. Schmit Oct 2009

Flexor Reflex Decreases During Sympathetic Stimulation In Chronic Human Spinal Cord Injury, Mark Kevin Garrison, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

A better understanding of autonomic influence on motor reflex pathways in spinal cord injury is important to the clinical management of autonomic dysreflexia and spasticity in spinal cord injured patients. The purpose of this study was to examine the modulation of flexor reflex windup during episodes of induced sympathetic activity in chronic human spinal cord injury (SCI). We simultaneously measured peripheral vascular conductance and the windup of the flexor reflex in response to conditioning stimuli of electrocutaneous stimulation to the opposite leg and bladder percussion. Flexor reflexes were quantified using torque measurements of the response to a noxious electrical stimulus …


Splenic Trauma As An Adverse Effect Of Torso-Protecting Side Airbags: Biomechanical And Case Evidence, Jason John Hallman, Karen J. Brasel, Narayan Yoganandan, Frank A. Pintar Oct 2009

Splenic Trauma As An Adverse Effect Of Torso-Protecting Side Airbags: Biomechanical And Case Evidence, Jason John Hallman, Karen J. Brasel, Narayan Yoganandan, Frank A. Pintar

Biomedical Engineering Faculty Research and Publications

Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity …