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Biomedical Engineering and Bioengineering Commons™
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- Keyword
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- Electrophysiology (2)
- Ischemia (2)
- Neurostimulation (2)
- Action Potentials (1)
- Alzheimer’s disease (1)
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- Analgesia (1)
- Artificial neural networks (1)
- Axon properties (1)
- Beeler Reuter (1)
- Bidomain (1)
- Biopotential (1)
- Brain Computer Interface (1)
- Cancer diagnosis (1)
- Cancer treatment (1)
- Cardiac Arrhythmia (1)
- Circuit (1)
- Computational Modeling (1)
- Cooling schedule (1)
- Corrected Maxwells Mixture (1)
- Decomposition (1)
- Demyelination simulation (1)
- Diagnostics (1)
- Dissection (1)
- EEG (1)
- EMG (1)
- EMG Decomposition (1)
- Electrical properties (1)
- Electroencephalography (1)
- Electromyography (1)
- Equivalent circuit neuron model (1)
Articles 1 - 27 of 27
Full-Text Articles in Biomedical Engineering and Bioengineering
Characterizing Direction Specific Ganglion Cell Receptor Activation Using A Perturbation Based Decomposition Method, Camila Paola Monchini Moline
Characterizing Direction Specific Ganglion Cell Receptor Activation Using A Perturbation Based Decomposition Method, Camila Paola Monchini Moline
Master's Theses
Characterizing postsynaptic current signals in the retina by neuroreceptor activation frequency is important for studying the mechanism of action behind phototransduction of varied visual stimuli. A better understanding could in turn lead to the creation of methods for early detection and prevention of debilitating optical neuropathies, such as glaucoma, age-related macular degeneration, and retinitis pigmentosa. More recent in-vitro and in-vivo studies have aimed to differentiate the effects of various neurotransmitters, such as acetylcholine, GABA, and glutamate, on receiving and processing different types of visual stimuli from the retina into the visual cortex.
The focus of this work will be to …
Modeling Action Potential Propagation During Hypertrophic Cardiomyopathy Through A Three-Dimensional Computational Model, Julia Elizabeth Kelley
Modeling Action Potential Propagation During Hypertrophic Cardiomyopathy Through A Three-Dimensional Computational Model, Julia Elizabeth Kelley
Master's Theses
Hypertrophic cardiomyopathy (HCM) is the most common monogenic disorder and the leading cause of sudden arrhythmic death in children and young adults. It is typically asymptomatic and first manifests itself during cardiac arrest, making it a challenge to diagnose in advance. Computational models can explore and reveal underlying molecular mechanisms in cardiac electrophysiology by allowing researchers to alter various parameters such as tissue size or ionic current amplitudes. The goal of this thesis is to develop a computational model in MATLAB and to determine if this model can accurately indicate cases of hypertrophic cardiomyopathy. This goal is achieved by combining …
The Effect Of Focused Ultrasound On Altering The Diameter Class Of Nerve Fibers Contributing To A Compound Evoked Potential, Analyzed Using A Perturbative Decomposition Technique., Megan Wurden
Master's Theses
Peripheral neuropathies are disorders that involve the damage of peripheral nerve fibers, affecting the ability of different parts of the body to communicate. A differentiating factor in diagnosis between various clinical conditions can be which size class of nerve fibers are affected. A nerve conduction velocity test can be used to assess the viability of the nerve but is a single-parameter test and gives no information about the population characteristics of the remaining active fibers. A method developed and previously reported by Szlavik (2016) utilizes a mathematical perturbed decomposition to determine the normalized frequency of each size class of fiber …
Single-Cell Impedance Spectroscopy, David Paul Lange
Single-Cell Impedance Spectroscopy, David Paul Lange
Master's Theses
Impedance spectroscopy (IS) is an important tool for cell detection and characterization in medical and food safety applications. In this thesis, the Cal Poly Biofluidics Lab’s impedance spectroscopy system was re-evaluated and optimized for single-cell impedance spectroscopy. To evaluate the IS system, an impedance spectroscopy bioMEMS chip was fabricated in the Cal Poly Microfabcrication lab, software was developed to run IS experiments, and studies were run to validate the system. To explore IS optimization, Maxwell’s mixture theorem and the Schwartz-Christoffel transform were used to calculate an analytic impedance solution to the co-planar electrode system,a novel volume fraction to account for …
Interpolated Perturbation-Based Decomposition As A Method For Eeg Source Localization, Gabriel Zelik Lipof
Interpolated Perturbation-Based Decomposition As A Method For Eeg Source Localization, Gabriel Zelik Lipof
Master's Theses
In this thesis, the perturbation-based decomposition technique developed by Szlavik [1] was used in an attempt to solve the inverse problem in EEG source localization. A set of dipole locations were forward modeled using a 4-layer sphere model of the head at uniformly distributed lead locations to form the vector basis necessary for the method. Both a two-dimensional and a pseudo-three-dimensional versions of the model were assessed with the two-dimensional model yielding decompositions with minimal error and the pseudo-three-dimensional version having unacceptable levels of error. The utility of interpolation as a method to reduce the number of data points to …
Perturbation Based Decomposition Of Semg Signals, Rachel Huettinger
Perturbation Based Decomposition Of Semg Signals, Rachel Huettinger
Master's Theses
Surface electromyography records the motor unit action potential signals in the vicinity of the electrode to reveal information on muscle activation. Decomposition of sEMG signals for characterization of constituent motor unit action potentials in terms of amplitude and firing times is useful for clinical research as well as diagnosis of neurological disorders. Successful decomposition of sEMG signals would allow for pertinent motor unit action potential information to be acquired without discomfort to the subject or the need for a well-trained operator (compared with intramuscular EMG). To determine amplitudes and firing times for motor unit action potentials in an sEMG recording, …
Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler
Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler
Master's Theses
Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …
Neuro-Silicon Interface Of A Hirudo Medicinalis Retzius Cell Integrated With Field Effect Transistor, Kurt Christian Sjoberg
Neuro-Silicon Interface Of A Hirudo Medicinalis Retzius Cell Integrated With Field Effect Transistor, Kurt Christian Sjoberg
Master's Theses
The focus of this thesis was to measure the intracellular voltage of a living neural cell using a silicon transistor. The coupling of neurological tissues with silicon devices is of interest to the fields of neurology, neuroscience, electrophysiology and cellular biology. In previous work by Peter Fromherz, single neurons were successfully coupled to transistors [1]. This thesis aims to show proof of concept of the fabrication of a simple neuro-silicon interface using wafer processing methods currently available at Cal Poly. The types of transistors and cells used, the methods for dissecting and preparing the cells, the electrophysiology methods for validating …
Computer-Aided Diagnoses (Cad) System: An Artificial Neural Network Approach To Mri Analysis And Diagnosis Of Alzheimer's Disease (Ad), Berizohar Padilla Cerezo
Computer-Aided Diagnoses (Cad) System: An Artificial Neural Network Approach To Mri Analysis And Diagnosis Of Alzheimer's Disease (Ad), Berizohar Padilla Cerezo
Master's Theses
Alzheimer’s disease (AD) is a chronic and progressive, irreversible syndrome that deteriorates the cognitive functions. Official death certificates of 2013 reported 84,767 deaths from Alzheimer’s disease, making it the 6th leading cause of death in the United States. The rate of AD is estimated to double by 2050. The neurodegeneration of AD occurs decades before symptoms of dementia are evident. Therefore, having an efficient methodology for the early and proper diagnosis can lead to more effective treatments.
Neuroimaging techniques such as magnetic resonance imaging (MRI) can detect changes in the brain of living subjects. Moreover, medical imaging techniques are the …
Interfacing A Hirudo Medicinalis Retzius Cell With Insulated Gate Of Mosfet, Rachel M. Smith
Interfacing A Hirudo Medicinalis Retzius Cell With Insulated Gate Of Mosfet, Rachel M. Smith
Master's Theses
Much work has been done to study the external stimulation of nervous tissue as well as the transmission of neural signals to electronics. Peter Fromherz was one of the pioneers in this area of electrophysiology, with a series of experiments in the 1990s that aimed to characterize and optimize the interface between neural tissue and transistors. In this thesis, Kurt Sjoberg and I interfaced a Retzius cell isolated from a Hirudo medicinalis ganglion with the insulated gate of a MOSFET. The goal was to see change in membrane potential that could be related Fromherz’s original 1991 work. Our experimental setup …
Characterizing Neurotransmitter Receptor Activation With A Perturbation Based Decomposition Method, Stephen Gregory Jue
Characterizing Neurotransmitter Receptor Activation With A Perturbation Based Decomposition Method, Stephen Gregory Jue
Master's Theses
The characterization of postsynaptic potentials, in terms of neurotransmitter receptor activation, is of clinical significance because information associated with receptor activation can be used in the diagnosis and study of neurological disorders. Single-unit recordings provide a method of measuring postsynaptic potentials in neurons using a microelectrode system, but yield no detailed information regarding the neurotransmitter receptors that contribute to the potential. To determine the types of neurotransmitter receptors that result in a compound postsynaptic potential from a microelectrode reading, decomposition of the potential is necessary. In this work, a perturbation-based decomposition method developed by R. Szlavik is evaluated for this …
Identifying And Predicting Rat Behavior Using Neural Networks, Jonathan A. Gettner
Identifying And Predicting Rat Behavior Using Neural Networks, Jonathan A. Gettner
Master's Theses
The hippocampus is known to play a critical role in episodic memory function. Understanding the relation between electrophysiological activity in a rat hippocampus and rat behavior may be helpful in studying pathological diseases that corrupt electrical signaling in the hippocampus, such as Parkinson’s and Alzheimer’s. Additionally, having a method to interpret rat behaviors from neural activity may help in understanding the dynamics of rat neural activity that are associated with certain identified behaviors.
In this thesis, neural networks are used as a black-box model to map electrophysiological data, representative of an ensemble of neurons in the hippocampus, to a T-maze, …
The Effects Of Transcutaneous Electrical Neurostimulation On Analgesia And Peripheral Perfusion, Leah I. Schafer
The Effects Of Transcutaneous Electrical Neurostimulation On Analgesia And Peripheral Perfusion, Leah I. Schafer
Master's Theses
Peripheral arterial occlusive disease (PAOD) affects 8 to 12 million Americans over the age of 50. As the disease progresses, arterial occlusions arising from atherosclerotic lesions inhibit normal metabolic vasodilation in the peripheries, resulting in limb ischemia and claudication. Pharmacological and surgical treatments currently used to treat both the hemodynamic and pain symptoms associated with PAOD can involve adverse and potentially life-threatening side effects. Thus, there is a need for additional innovative therapies for PAOD.
Neurostimulation has a known analgesic effect on both acute and chronic pain. Although the exact mechanisms remain under investigation, local vascular tone may be modulated …
Quantification Of Blood Flow Velocity Using Color Sensing, Aditya Deepak Sanghani
Quantification Of Blood Flow Velocity Using Color Sensing, Aditya Deepak Sanghani
Master's Theses
Blood flow velocity is an important parameter that can give information on several pathologies including atherosclerosis, glaucoma, Raynaud’s phenomenon, and ischemic stroke [2,5,6,10]. Present techniques of measuring blood flow velocity involve expensive procedures such as Doppler echocardiography, Doppler ultrasound, and magnetic resonance imaging [11,12]. They cost from $8500-$20000. It is desired to find a low-cost yet equally effective solution for measuring blood flow velocity. This thesis has a goal of creating a proof of concept device for measuring blood flow velocity.
Finger blood flow velocity is investigated in this project. The close proximity to the skin of the finger’s arteries …
Comparison Of Regular Ringer's Solution And Glucose Ringer's Solution On The Longevity Of The Hirudo Medicinalis' Retzius Cell, Nicole Arielle Peretti
Comparison Of Regular Ringer's Solution And Glucose Ringer's Solution On The Longevity Of The Hirudo Medicinalis' Retzius Cell, Nicole Arielle Peretti
Master's Theses
In 1882, Sydney Ringer, a professor of medicine at University College in London, experimented with the frog ventricle to better understand how each constituent of blood influences contraction. The ultimate goal was to create an artificial circulating fluid to use for the perfusion of isolated organs, in this case, a frog heart. Today, Ringer’s solution is still used in research for physiological studies requiring the survival and maintenance of specimens outside of their host bodies. One such example is the use of medicinal leech ganglia for electrophysiological measurements. In this thesis, I am comparing two Ringer’s solutions, original versus added …
Nerve Fiber Diameter Measurements Using Hematoxylin And Eosin Staining And Brightfield Microscopy To Assess The Novel Method Of Characterizing Peripheral Nerve Fiber Distributions By Group Delay, Jorge Arturo Vazquez
Nerve Fiber Diameter Measurements Using Hematoxylin And Eosin Staining And Brightfield Microscopy To Assess The Novel Method Of Characterizing Peripheral Nerve Fiber Distributions By Group Delay, Jorge Arturo Vazquez
Master's Theses
Peripheral neuropathies are a set of common diseases that affect the peripheral nervous system, causing damage to vital connections between various parts of the body and the brain and spinal cord. Different clinical conditions are known to selectively impact various size nerve fibers, which often makes it difficult to diagnose which peripheral neuropathy a patient might have. The nerve conduction velocity diagnostic test provides clinically useful information in the diagnosis of some peripheral neuropathies. This method is advantageous because it tends to be minimally invasive yet it provides valuable diagnostic information. However, this test does not determine characteristics of peripheral …
Investigating Hemodynamic Responses To Electrical Neurostimulation, Sean Youra
Investigating Hemodynamic Responses To Electrical Neurostimulation, Sean Youra
Master's Theses
Since the 1900s, the number of deaths attributable to cardiovascular disease has steadily risen. With the advent of antihypertensive drugs and non-invasive surgical procedures, such as intravascular stenting, these numbers have begun to level off. Despite this trend, the number of patients diagnosed with some form of cardiovascular disease has only increased. By 2030, prevalence of coronary heart disease is expected to increase approximately by 18% in the United States. By 2050, prevalence of peripheral arterial occlusive disease is expected to increase approximately by 98% in the U.S. No single drug or surgical intervention offers a complete solution to these …
Neuromodulation: Action Potential Modeling, Vladimir Ruzov
Neuromodulation: Action Potential Modeling, Vladimir Ruzov
Master's Theses
There have been many different studies performed in order to examine various properties of neurons. One of the most important properties of neurons is an ability to originate and propagate action potential. The action potential is a source of communication between different neural structures located in different anatomical regions. Many different studies use modeling to describe the action potential and its properties. These models mathematically describe physical properties of neurons and analyze and explain biological and electrochemical processes such as action potential initiation and propagation. Therefore, one of the most important functions of neurons is an ability to provide communication …
Computational Modeling To Evaluate Helical Electrode Designs For Use In Vagus Nerve Stimulation, Anthony W. Cowley
Computational Modeling To Evaluate Helical Electrode Designs For Use In Vagus Nerve Stimulation, Anthony W. Cowley
Master's Theses
An estimated 0.5% of world’s population has been diagnosed with epilepsy. Of these patients 20-30% will be unable to achieve seizure control with anti-epileptic drugs. Vagus nerve stimulation (VNS) may be an appropriate treatment option for some patients with pharmaceutically refractory, partial-onset seizures.
VNS therapy uses a helical electrode to interface between the implantable pulse generator and the vagus nerve. While there have been several studies related to the mechanical and electrical safety of such electrodes, little work has been done toward understanding the effectiveness of the helical electrode in nerve stimulation. A better understanding of the voltage field and …
Tracking Points On A Pacing Lead In A Beating Heart, Avinash Ramesh Varma
Tracking Points On A Pacing Lead In A Beating Heart, Avinash Ramesh Varma
Master's Theses
Heart failure is a common condition during which the pumping action of the heart is affected because the heart does not contract or relax properly. Heart failure affects about 5 million Americans, with 550,000 new cases diagnosed each year. Cardiac resynchronization therapy (CRT) is used to treat symptoms and other complications associated with a heart failure. While performing CRT, Implantation of a pacing lead in the left ventricle of the heart is a very challenging surgical procedure performed with fluoroscopy. The target location is often difficult to reach through the tortuous coronary venous anatomy, which varies greatly among individuals. Placement …
Implementation Of Novel Group Delay Decomposition Method And Surgical Protocol For Assessing Peripheral Neuropathy, Sammy Paul Nicolas
Implementation Of Novel Group Delay Decomposition Method And Surgical Protocol For Assessing Peripheral Neuropathy, Sammy Paul Nicolas
Master's Theses
This paper outlines a surgical procedure for exposing and stimulating the sciatic nerve of an anesthetized rodent for purposes of obtaining conduction velocity readings. The ability to accurately quantify nerve conduction velocity has potential for use in the field of diagnostic medicine and disease characterization. An accurate reading depends on both the surgical method used to expose the desired nerve without imposing onto it any physical trauma as well as the stimulation protocol used to initiate action potentials. This paper contains the specific steps required to set up the necessary hardware and software for electrical stimulation as well as a …
Implementation Of Medicinal Leech Preparation To Investigate The Connection Between The Motor Neuron And Muscle Fiber Via Sharp Electrode Electrophysiology, Chandra Nikole Miller
Implementation Of Medicinal Leech Preparation To Investigate The Connection Between The Motor Neuron And Muscle Fiber Via Sharp Electrode Electrophysiology, Chandra Nikole Miller
Master's Theses
There are forty registered organophosphates in the United States and they range from pesticides and insecticides to nerve agents or neurotoxins such as sarin. Organophosphates (OP’s) have been used in chemical warfare for years and tend to lead to death due to an attack on the nervous system. Chemical assays and mass microscopy have been used to assess the concentration of OP’s in the environment, but both methods require the body to metabolize the OP first, which can be detrimental to the victim. It is crucial to come up with a method to investigate and detect these neurotoxins without causing …
Equivalent Circuit Implementation Of Demyelinated Human Neuron In Spice, Nathan A. Angel
Equivalent Circuit Implementation Of Demyelinated Human Neuron In Spice, Nathan A. Angel
Master's Theses
This work focuses on modeling a demyelinated Hodgkin and Huxley (HH) neuron with Simulated Program with Integrated Circuit Emphasis (SPICE) platform. Demyelinating disorders affect over 350,000 people in the U.S and understanding the demyelination process at the cellular level is necessary to find safe ways to treat the diseases [9]. Utilizing a previous SPICE model of an electrically small cell neuron developed by Szlavik [32], an extended core conductor myelinated neuron was produced in this work. The myelinated neuron developed has seven active Nodes of Ranvier (nodes) separated by a myelin sheath. The myelin sheath can be successfully modeled with …
Characterizing Nerve Fiber Activation By Varying Fiber Diameter And Depth Within A Conductive Medium: A Finite Element Approach, Nathan Daniel Soto
Characterizing Nerve Fiber Activation By Varying Fiber Diameter And Depth Within A Conductive Medium: A Finite Element Approach, Nathan Daniel Soto
Master's Theses
In some instances neuropathies can be diagnosed through a conduction velocity test. However, not all neuropathies can be classified using this method. Gaining an understanding of how the stimulus level varies for different fiber sizes at different fiber depths within a conductive medium will provide useful information for simulation studies.
Following a two-step approach using COMSOL and MATLAB, a simulation was implemented to investigate the stimulus necessary to activate different sized fibers at different depths. In this two-step approach, COMSOL was used to describe the voltage profile that would be present within a conductive medium after a stimulus was applied. …
Investigation Of A Simulated Annealing Cooling Schedule Used To Optimize The Estimation Of The Fiber Diameter Distribution In A Peripheral Nerve Trunk, Arya Vigeh
Master's Theses
In previous studies it was determined that the fiber diameter distribution in a peripheral nerve could be estimated by a simulation technique known as group delay. These results could be further improved using a combinatorial optimization algorithm called simulated annealing. This paper explores the structure and behavior of simulated annealing for the application of optimizing the group delay estimated fiber diameter distribution. Specifically, a set of parameters known as the cooling schedule is investigated to determine its effectiveness in the optimization process.
Simulated annealing is a technique for finding the global minimum (or maximum) of a cost function which may …
The Electrical Properties Of Human Tissue For The Diagnosis And Treatment Of Melanoma Skin Cancer, Glenn Cameron Stante
The Electrical Properties Of Human Tissue For The Diagnosis And Treatment Of Melanoma Skin Cancer, Glenn Cameron Stante
Master's Theses
This thesis discusses the research, experimental methods, and data gathered for the investigation of a novel method for the diagnosis of melanoma skin cancer. First, a background about human skin tissue is presented. Then, a detailed description of melanoma along with current diagnosis techniques and treatment options are presented. In the experimental methods, the electrical properties of several types of tissue were analyzed, the purpose of which was to discover if a tissue type can be distinguished by its electrical properties alone. This would allow for the diagnosis of melanoma to be done by examining the electrical properties of the …
Time-Frequency Analysis Of Intracardiac Electrogram, Erik Brockman
Time-Frequency Analysis Of Intracardiac Electrogram, Erik Brockman
Master's Theses
The Cardiac Rhythm Management Division of St. Jude Medical specializes in the development of implantable cardioverter defibrillators that improve the quality of life for patients diagnosed with a variety of cardiac arrhythmias, especially for patients prone to sudden cardiac death. With the goal to improve detection of cardiac arrhythmias, this study explored the value in time-frequency analysis of intracardiac electrogram in four steps. The first two steps characterized, in the frequency domain, the waveforms that construct the cardiac cycle. The third step developed a new algorithm that putatively provides the least computationally expensive way to identifying cardiac waveforms in the …