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Fracture Of Bone Using Microindentation, Séverine Vennin Aug 2010

Fracture Of Bone Using Microindentation, Séverine Vennin

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Osteoporosis is a current disease which is especially of concern to post-menopausal women. It is characterized by a decrease of bone density and an increase in the risk of fracture. Interest in the fracture mechanisms with respect to the underlying biological structure of the bone is of great interest to researchers in this field. In this thesis, a new method based on microindentation on rat femurs was developed to determine the relation between the viscoelastic and the fracture properties of bone. The main goal is to measure the viscoelastic properties by using a dynamic mechanical analysis indentation method and then …


Development Of Tissue Engineered Test Systems To Study Mammary Cell Interactions In Vitro, Cheryl Cass Aug 2010

Development Of Tissue Engineered Test Systems To Study Mammary Cell Interactions In Vitro, Cheryl Cass

All Dissertations

The work described in this dissertation was conducted in the interdisciplinary research environment of the Clemson University Institute for Biological Interfaces of Engineering. A note at the beginning of each chapter acknowledges, as relevant, collaborating doctoral students and reminds the reader where work from each chapter has been presented or published. The overall goal of this work was to develop tissue engineered test system methodologies to allow the study of mammary cell interactions in vitro. The background, as described in Chapter 1, was published in part in Philosophical Transactions of the Royal Society A in 2010. The studies were designed …


A Molecular Dynamics Study On The Transport Of A Charged Biomolecule In A Polymeric Adsorbent Medium And Its Adsorption Onto A Charged Ligand, Enrico Riccardi, Jee-Ching Wang, Athanasios I. Liapis Aug 2010

A Molecular Dynamics Study On The Transport Of A Charged Biomolecule In A Polymeric Adsorbent Medium And Its Adsorption Onto A Charged Ligand, Enrico Riccardi, Jee-Ching Wang, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

The transport of a charged adsorbate biomolecule in a porous polymeric adsorbent medium and its adsorption onto the covalently immobilized ligands have been modeled and investigated using molecular dynamics modeling and simulations as the third part of a novel fundamental methodology developed for studying ion-exchange chromatography based bioseparations. To overcome computational challenges, a novel simulation approach is devised where appropriate atomistic and coarse grain models are employed simultaneously and the transport of the adsorbate is characterized through a number of locations representative of the progress of the transport process. The adsorbate biomolecule for the system studied in this work changes …


Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz Aug 2010

Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz

Faculty Publications

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility …


A Spectroscopic Investigation Into The Setting And Mechanical Properties Of Titanium Containing Glass Polyalkenoate Cements, A. W. Wren, A. Kidari, N. M. Cummins, Mark R. Towler Aug 2010

A Spectroscopic Investigation Into The Setting And Mechanical Properties Of Titanium Containing Glass Polyalkenoate Cements, A. W. Wren, A. Kidari, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Titanium (Ti) implants are extensively used in a number of biomedical and dental applications. This work introduces Ti into the glass phase of a zinc-based glass polyalkenoate cement (GPC) and investigates changes in handling and mechanical properties considering two molecular weight polyacrylic acids (PAA), E9 and E11. Considering the handling properties, the working time (Tw) increased from 50 sE9, 32 sE11 (BT 101, Ti-free) to 169 sE9, 74 sE11 with TW-Z (highest Ti content), respectively. The setting time (Ts) increased from 76 sE9, 47 sE11 (BT 101) …


Effect Of Mechanical Stimulation On Mesenchymal Stem Cell Seeded Cartilage Constructs, Karin Wartella Jul 2010

Effect Of Mechanical Stimulation On Mesenchymal Stem Cell Seeded Cartilage Constructs, Karin Wartella

Theses and Dissertations

Cartilage tissue engineered constructs using mesenchymal stem cells were stimulated with 3 different stimulation algorithms to achieve characteristics mimicking the superficial tangential zone of articular cartilage. The stimulation algorithm of both compression and tension without an offset had the best properties out of all the evaluated groups.


Characterizing Accuracy Of Total Hemoglobin Recovery Using Contrast-Detail Analysis In 3d Image-Guided Near Infrared Spectroscopy With The Boundary Element Method, Hamid R. Ghadyani, Subhadra Srinivasan, Brian W. Pogue, Keith D. Paulsen Jul 2010

Characterizing Accuracy Of Total Hemoglobin Recovery Using Contrast-Detail Analysis In 3d Image-Guided Near Infrared Spectroscopy With The Boundary Element Method, Hamid R. Ghadyani, Subhadra Srinivasan, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

The quantification of total hemoglobin concentration (HbT) obtained from multi-modality image-guided near infrared spectroscopy (IG-NIRS) was characterized using the boundary element method (BEM) for 3D image reconstruction. Multi-modality IG-NIRS systems use a priori information to guide the reconstruction process. While this has been shown to improve resolution, the effect on quantitative accuracy is unclear. Here, through systematic contrast-detail analysis, the fidelity of IG-NIRS in quantifying HbT was examined using 3D simulations. These simulations show that HbT could be recovered for medium sized (20mm in 100mm total diameter) spherical inclusions with an average error of 15%, for the physiologically …


Impedance Imaging And Measurements By Micro Probes In Aqueous Environments, Tao Shang Jul 2010

Impedance Imaging And Measurements By Micro Probes In Aqueous Environments, Tao Shang

Theses and Dissertations

The dissertation presented here describes two research projects that may, at first glance, seem unrelated. Their unifying principle is the measurement of electrical impedance for the detection and analysis of biological materials. Impedance measurements have long been employed and studied in scientific fields, and the dissertation begins with a summary of historical methodology, applications, and terminology. Utilizing impedance measurements for microscopic imaging is the driving motivation for Scanning Impedance Imaging (SII). This technique manifests the distribution of electrical impedance inside biological tissues and is described after the dissertation's introduction. SII can provide micron-scale imaging resolution by scanning a shielded microprobe …


Modeling, Design, And Testing Of Contact-Aided Compliant Mechanisms In Spinal Arthroplasty, Peter Andrew Halverson Jul 2010

Modeling, Design, And Testing Of Contact-Aided Compliant Mechanisms In Spinal Arthroplasty, Peter Andrew Halverson

Theses and Dissertations

Injury, instrumentation, or surgery may change the functional biomechanics of the spine. Spinal fusion, the current surgical treatment of choice, stabilizes the spine by rigid fixation, reducing spinal mobility at the cost of increased stress at adjacent levels. Recently, alternatives to spinal fusion have been investigated. One such alternative is total disc replacements. The current generation of total disc replacements (TDRs) focuses on restoring the quantity of motion. Recent studies indicate that the moment-rotation response and axis of rotation, or quality of motion (QOM), may have important implications in the health of adjacent segments as well as the health of …


Application Of A Bayesian Inference Method To Reconstruct Short-Range Atmospheric Dispersion Events, Inanc Senocak Jul 2010

Application Of A Bayesian Inference Method To Reconstruct Short-Range Atmospheric Dispersion Events, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

In the event of an accidental or intentional release of chemical or biological (CB) agents into the atmosphere, first responders and decision makers need to rapidly locate and characterize the source of dispersion events using limited information from sensor networks. In this study the stochastic event reconstruction tool (SERT) is applied to a subset of the Fusing Sensor Information from Observing Networks (FUSION) Field Trial 2007 (FFT 07) database. The inference in SERT is based on Bayesian inference with Markov chain Monte Carlo (MCMC) sampling. SERT adopts a probability model that takes into account both positive and zero-reading sensors. In …


Concurrently Evolving Sensor Morphology And Control For A Hexapod Robot, Gary Parker, Pramod J. Nathan Jul 2010

Concurrently Evolving Sensor Morphology And Control For A Hexapod Robot, Gary Parker, Pramod J. Nathan

Computer Science Faculty Publications

Evolving a robot’s sensor morphology along with its control program has the potential to significantly improve its effectiveness in completing the assigned task, plus accommodates the possibility of allowing it to adapt to significant changes in the environment. In previous work, we presented a learning system where the angle, range, and type of sensors on a hexapod robot, along with the control program, were evolved. The evolution was done in simulation and the tests, which were also done in simulation, showed that effective sensor morphologies and control programs could be co-learned by the system. In this paper, we describe the …


Using Evolutionary Strategies For The Real-Time Learning Of Controllers For Autonomous Agents In Xpilot-Ai, Gary Parker, Michael H. Probst Jul 2010

Using Evolutionary Strategies For The Real-Time Learning Of Controllers For Autonomous Agents In Xpilot-Ai, Gary Parker, Michael H. Probst

Computer Science Faculty Publications

Real-time learning is the process of an artificial intelligence agent learning behavior(s) at the same pace as it operates in the real world. Video games tend to be an excellent locale for testing real-time learning agents, as the action happens at real speeds with a good visual feedback mechanism, coupled with the possibility of comparing human performance to that of the agent's. In addition, players want to be competing against a consistently challenging opponent. This paper is a discussion of a controller for an agent in the space combat game Xpilot and the evolution of said controller using two different …


Tribological Comparison Of Traditional And Advanced Firearm Coatings, Greg Boban Jul 2010

Tribological Comparison Of Traditional And Advanced Firearm Coatings, Greg Boban

Master's Theses

The objective of this project is to find which type of coating has the best performance characteristics for finishing firearms. This is accomplished by measuring and comparing several performance characteristics, such as: adhesion, hardness, wear resistance, friction control, and corrosion resistance. Appearance is not a factor since any exterior coating that is flashy can be subdued or camouflaged with special purpose paints, which have proven durable enough for such purposes. Cost will not be a limiting factor for this experiment, but will be discussed in the conclusion as a secondary concern. This data will be used to identify the best …


Department Of Biological Systems Engineering Newsletter, Volume 6, Number 2, July 2010 Jul 2010

Department Of Biological Systems Engineering Newsletter, Volume 6, Number 2, July 2010

BSE Department Magazine

No abstract provided.


Modeling And Its Numerical Method For Micro-Scaled Diffusion -Reaction Systems In The Neuromuscular Junction, Abdul Khaliq Jul 2010

Modeling And Its Numerical Method For Micro-Scaled Diffusion -Reaction Systems In The Neuromuscular Junction, Abdul Khaliq

Doctoral Dissertations

The main subject of this research is the neuromuscular junction (NMJ). The NMJ is a biological structure composed of the interface between a neuron and a muscle cell. Currently, there is not a fully three dimensional model of diffusion-reaction processes occurring in the NMJ. Developing a useful predictive model of this structure will assist in the therapeutic efforts to restore and rehabilitate NMJ function to humans and in developing strategies to prevent damage to the NMJ. This research work developed 1D mass transport and full 3D reaction diffusion models. A new finite difference scheme is presented for solving 1D mass …


In Vivo Non-Invasive Monitoring Of Optically Resonant Metal Nanoparticles Using Multi-Wavelength Photoplethysmography, Gregory J. Michalak Jul 2010

In Vivo Non-Invasive Monitoring Of Optically Resonant Metal Nanoparticles Using Multi-Wavelength Photoplethysmography, Gregory J. Michalak

Doctoral Dissertations

Nanotechnology has recently emerged as a powerful modality in many biomedical applications. In particular, several classes of nanoparticles have been employed as cancer therapy and imaging contrast agents. These particles can have architecture of varying complexity, depending on their specific application. These complex architectures are achieved by various chemical techniques usually performed in specific sequences to add complexity and functionality. One such class of nanoparticle, used in tumor treatment and as contrast agents in several optical imaging techniques, is the plasmon resonant metal nanoparticle. The most common metal used for these particles is gold because of its biocompatibility, lack of …


Recombinant Factors For Hemostasis, Jennifer Calcaterra Jul 2010

Recombinant Factors For Hemostasis, Jennifer Calcaterra

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Trauma deaths are a result of hemorrhage in 37% of civilians and 47% military personnel and are the primary cause of death for individuals under 44 years of age. Current techniques used to treat hemorrhage are inadequate for severe bleeding. Preliminary research indicates that fibrin sealants (FS) alone or in combination with a dressing may be more effective; however, it has not been economically feasible for widespread use because of prohibitive costs related to procuring the proteins. To meet future demands for hemostatic therapies, FS will likely include recombinant human fibrinogen (rFI) and recombinant human Factor XIII (rFXIII). The underlying …


Informatics And Natural Computation: Final Report, Francis T. Marchese Jul 2010

Informatics And Natural Computation: Final Report, Francis T. Marchese

Cornerstone 3 Reports : Interdisciplinary Informatics

The purpose of this grant is to develop an interdisciplinary course in Informatics and Natural Computation that would service undergraduate computer, natural, and physical science majors. Informatics is the science of information, the practice of information processing, and the engineering of information systems. Informatics studies the structure, algorithms, behavior, and interactions of natural and artificial systems that store, process, access and communicate information. Natural computing refers to a collection of disciplines that unite nature with computing in three distinct ways:

1. Nature serves as a source of inspiration for the development of computational tools or systems that are used for …


High Performance Atomic-Layer-Deposited Laluo3/Ge-On-Insulator P-Channel Metal-Oxide-Semiconductor Field-Effect Transistor With Thermally Grown Geo2 As Interfacial Passivation Layer, J J. Gu, Y Q. Liu, M Xu, G K. Celler, R G. Gordon, P. D. Ye Jul 2010

High Performance Atomic-Layer-Deposited Laluo3/Ge-On-Insulator P-Channel Metal-Oxide-Semiconductor Field-Effect Transistor With Thermally Grown Geo2 As Interfacial Passivation Layer, J J. Gu, Y Q. Liu, M Xu, G K. Celler, R G. Gordon, P. D. Ye

Birck and NCN Publications

Enhancement-mode p-channel metal-oxide-semiconductor field-effect transistor (MOSFET) on germanium-on-insulator substrate is fabricated with atomic-layer-deposited (ALD) LaLuO3 as gate dielectric. Significant improvement in both on-state current and effective hole mobility has been observed for devices with thermal GeO2 passivation. The negative threshold voltage (V-T) shift in devices with GeO2 interfacial layer (IL) further demonstrates the effectiveness of surface passivation. Results from low temperature mobility characterization show that phonon scattering is the dominant scattering mechanism at a large inversion charge, indicating good interface quality. The combination of higher-k LaLuO3 and ultrathin GeO2 IL is a promising solution to the tradeoff between the aggressive …


Nonlinear Observers For Human-In-The-Loop Control Systems, Samuel Kitchen Mckinley Jul 2010

Nonlinear Observers For Human-In-The-Loop Control Systems, Samuel Kitchen Mckinley

Master's Theses - Daytona Beach

The development of models for a human-in-the-loop with hardware is an area of ongoing research. The ability to simulate a human-in-the-loop with hardware provides a platform for better understanding the dynamics of human and machine cognition. A human-in-the-loop model provides information that can be used to design more efficient human interfaces and smarter autonomous assistant controllers. This can make a complex task such as flying an aircraft safer and more accessible. This thesis explores different possibilities for human operator models to be modeled in the loop with a vehicle. A human is modeled as a linear state feedback controller in …


Implementation Of Physiologic Pressure Conditions In A Blood Vessel Mimic Bioreactor System, Kevin Mark Okarski Jul 2010

Implementation Of Physiologic Pressure Conditions In A Blood Vessel Mimic Bioreactor System, Kevin Mark Okarski

Master's Theses

ABSTRACT

Implementation of Physiologic Pressure Conditions in a Blood Vessel Mimic Bioreactor System

Kevin Mark Okarski

Tissue engineering has traditionally been pursued as a therapeutic science intended for restoring or replacing diseased or damaged biologic tissues or organs. Cal Poly’s Blood Vessel Mimic Laboratory is developing a novel application of tissue engineering as a tool for the preclinical evaluation of intravascular devices. The blood vessel mimic (BVM) system has been previously used to assess the tissue response to deployed stents, but under non-physiologic conditions. Since then, efforts have been made to improve the vessel and bioreactor’s ability to emulate in …


Scan Loss Pattern Synthesis For Adaptive Array Ground Stations, William C. Barott, Mary Ann Ingram, Paul G. Steffes Jul 2010

Scan Loss Pattern Synthesis For Adaptive Array Ground Stations, William C. Barott, Mary Ann Ingram, Paul G. Steffes

Publications

We present several techniques for maximizing the contact time between low Earth orbiting satellites (LEOs) and a ground station (GS). The GS comprises an adaptive array of electronically steered space-fed lenses (SFLs). Each SFL is manufactured as a low-cost printed circuit with the result that it exhibits scanning loss. By differently orienting the boresights of the SFLs in the adaptive array, the SFL's scanning losses can be made to optimally complement the path loss of the LEO, thereby reducing the cost of the GS while maximizing the download capacity of the satellite link. The optimization, implemented with a genetic algorithm …


Development Of Experimental Methods To Assess Adsorption Free Energy For Peptide-Surface Interactions, Yang Wei Jul 2010

Development Of Experimental Methods To Assess Adsorption Free Energy For Peptide-Surface Interactions, Yang Wei

All Dissertations

Because of its governing role in cellular response to implants and substrates for biomedical applications, the understanding and control of protein adsorption to material surfaces has been one of the major topics of research in the field of biomaterials. Unfortunately, it has proven to be extremely difficult to quantitatively understand and control these types of interactions because of the complexities involved, and existing methods that have been developed and used to characterize protein-surface interactions have proved to be inadequate to provide the level of detail necessary to achieve this understanding. New, more fundamental methods, both experimental and computational, are needed …


Securing Foreign Oil: A Case For Including Military Operations In The Climate Change Impact Of Fuels, Adam J. Liska, Richard K. Perrin Jul 2010

Securing Foreign Oil: A Case For Including Military Operations In The Climate Change Impact Of Fuels, Adam J. Liska, Richard K. Perrin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Military operations are major industrial activities that use massive amounts of fuel and materials that significantly contribute to climate change. In this article, we assert that military activity to protect international oil trade is a direct production component for importing foreign oil— as necessary for imports as are pipelines and supertankers—and therefore the greenhouse gas (GHG) emissions from that military activity are relevant to U.S. fuel policies related to climate change. Military security for protection of global maritime petroleum distribution is part of the acquisition process, but in addition, recent Middle Eastern wars may also be related to securing petroleum …


Optimizing And Benchmarking Returnable Container Processes Within An Automotive Distribution System, Camille Chism Jul 2010

Optimizing And Benchmarking Returnable Container Processes Within An Automotive Distribution System, Camille Chism

Theses

An analysis of Reusable Packaging in automobile manufacturing facilities, as well as a comparison to other industries, shows that returnable container systems are not being fully utilized.

In this study, methods to return and track packaging materials for reuse are examined. Issues identified through surveys and interviews are summarized, and a recommendation to more fully utilize systems currently in place is proposed. An evaluation based on utilizing the current system will enable us to assign a cost to current operations, and may support an investment in improved systems and technologies.

Most of the companies surveyed gauge functionality based on whether …


Biogeography-Based Optimization Of Neuro-Fuzzy System Parameters For Diagnosis Of Cardiac Disease, Mirela Ovreiu, Daniel J. Simon Jul 2010

Biogeography-Based Optimization Of Neuro-Fuzzy System Parameters For Diagnosis Of Cardiac Disease, Mirela Ovreiu, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Cardiomyopathy refers to diseases of the heart muscle that becomes enlarged, thick, or rigid. These changes affect the electrical stability of the myocardial cells, which in turn predisposes the heart to failure or arrhythmias. Cardiomyopathy in its two common forms, dilated and hypertrophic, implies enlargement of the atria; therefore, we investigate its diagnosis through P wave features. In particular, we design a neuro-fuzzy network trained with a new evolutionary algorithm called biogeography-based optimization (BBO). The neuro-fuzzy network recognizes and classifies P wave features for the diagnosis of cardiomyopathy. In addition, we incorporate opposition-based learning in the BBO algorithm for improved …


Biogeography-Based Optimization With Blended Migration For Constrained Optimization Problems, Haiping Ma, Daniel J. Simon Jul 2010

Biogeography-Based Optimization With Blended Migration For Constrained Optimization Problems, Haiping Ma, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Biogeography-based optimization (BBO) is a new evolutionary algorithm based on the science of biogeography. We propose two extensions to BBO. First, we propose blended migration. Second, we modify BBO to solve constrained optimization problems. The constrained BBO algorithm is compared with solutions based on a genetic algorithm (GA) and particle swarm optimization (PSO). Numerical results indicate that BBO generally performs better than GA and PSO in handling constrained single-objective optimization problems.


Developing Sustainable Life Support System Concepts, Evan A. Thomas Jul 2010

Developing Sustainable Life Support System Concepts, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Sustainable spacecraft life support concepts may allow the development of more reliable technologies for long-duration space missions. Currently, life support technologies at different levels of development are not well evaluated against each other, and evaluation methods do not account for long-term reliability and sustainability of the hardware. This paper presents point-of-departure Sustainable System Mass (SSM) evaluation criteria for life support systems that may allow more robust technology development, testing, and comparison. An example sustainable water recovery system concept is presented.


Mechanical Testing Device For Viscoelastic Biomaterials, Jeff D. Berg Jul 2010

Mechanical Testing Device For Viscoelastic Biomaterials, Jeff D. Berg

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

Nearly all biologic tissues exhibit viscoelastic behavior. This behavior is characterized by hysteresis in the response of the material to load or strain. This information can be utilized in extrapolation of life expectancy of vascular implant materials including native tissues and synthetic materials. This behavior is exhibited in many engineering materials as well such as the polymers PTFE, polyamide, polyethylene, etc. While procedures have been developed for evaluating the engineering polymers the techniques for biologic tissues are not as mature. There are multiple reasons for this. A major one is a cultural divide between the medical and engineering communities. Biomedical …


Simulation Of Temperature Distributions In Tissue Upon Laser Pulse Irradiation Including Water Mass Transfer, Deepthi Nagulapally Jul 2010

Simulation Of Temperature Distributions In Tissue Upon Laser Pulse Irradiation Including Water Mass Transfer, Deepthi Nagulapally

Electrical & Computer Engineering Theses & Dissertations

Lasers, due to their unique characteristics, have tremendous applications in the medical field. Generally all laser applications in hie-medicine involve the propagation of laser energy through tissue. Energy is deposited giving rise to many physical, hie-chemical, and mechanical effects. Among these are dynamical changes in the local temperature distributions within the tissue. Analysis of the temperature changes requires the creation of an appropriate optical transmission and heat flow model that incorporates user specified laser parameters. Here, a numerical simulation model was developed to study both steady state and time dependent temperature distributions due to pulsed laser radiation within user specified …