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Articles 31 - 53 of 53

Full-Text Articles in Bioelectrical and Neuroengineering

A Comprehensive Analysis On Eeg Signal Classification Using Advanced Computational Analysis, Kaushik Bhimraj Jan 2017

A Comprehensive Analysis On Eeg Signal Classification Using Advanced Computational Analysis, Kaushik Bhimraj

College of Graduate Studies: Theses & Dissertations

Electroencephalogram (EEG) has been used in a wide array of applications to study mental disorders. Due to its non-invasive and low-cost features, EEG has become a viable instrument in Brain-Computer Interfaces (BCI). These BCI systems integrate user's neural features with robotic machines to perform tasks. However, due to EEG signals being highly dynamic in nature, BCI systems are still unstable and prone to unanticipated noise interference. An important application of this technology is to help facilitate the lives of the tetraplegic through assimilating human brain impulses and converting them into mechanical motion. However, BCI systems are remarkably challenging to implement …


Mechanical Reliability Of Implantable Polyimide-Based Magnetic Microactuators For Biofouling Removal, Christian G. Figueroa-Espada, Qi Yang, Hyowon Lee Aug 2016

Mechanical Reliability Of Implantable Polyimide-Based Magnetic Microactuators For Biofouling Removal, Christian G. Figueroa-Espada, Qi Yang, Hyowon Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydrocephalus is a neurological disorder that typically requires a long-term implantation of a shunt system to manage its symptoms. These shunt systems are notorious for their extremely high failure rate. More than 40% of all implanted shunt systems fail within the first year of implantation. On average, 85% of all hydrocephalus patients with shunt systems undergo at least two shunt-revision surgeries within 10 years of implantation. A large portion of this high failure rate can be attributed to biofouling-related obstructions and infections. Previously, we developed flexible polyimide-based magnetic microactuators to remove obstructions formed on hydrocephalus shunts. To test the long-term …


Automated Microscopy Platform For High-Throughput Analysis Of Cellular Characteristics, Hussam Ibrahim Jul 2016

Automated Microscopy Platform For High-Throughput Analysis Of Cellular Characteristics, Hussam Ibrahim

Physics: Student Scholarship & Creative Works

Existing microscopy platforms allow analysis post-hoc, but not in real time. This is an issue in the world of Bioengineering because you are limited to performing further analysis on specimen. The aim of my research was to design a sophisticated system whereby information can be exchanged between the software which acquires images and software that analyzes the images immediately after acquisition. In this system, images would be acquired by the microscope and analyzed by customized scripts (MATLAB, Mathworks) in real time. Specifically, MATLAB would wait for new images to be saved on the hard drive, import these images, and perform …


Utilizing Brain-Computer Interfacing To Control Neuroprosthetic Devices, Cheyne J. Angy Apr 2016

Utilizing Brain-Computer Interfacing To Control Neuroprosthetic Devices, Cheyne J. Angy

Senior Honors Theses

Advances in neuroprosthetics in recent years have made an enormous impact on the quality of life for many people with disabilities, helping them regain the functionality of damaged or impaired abilities. One of the main hurdles to regaining full functionality regarding neuroprosthetics is the integration between the neural prosthetic device and the method in which the neural prosthetic device is controlled or manipulated to function correctly and efficiently. One of the most promising methods for integrating neural prosthetics to an efficient method of control is through Brian-computer Interfacing (BCI). With this method, the neuroprosthetic device is integrated into the human …


Intracellular Ros Mediates Gas Plasma-Facilitated Cellular Transfection In 2d And 3d Cultures, Dehui Xu, Biqing Wang, Yujing Xu, Zeyu Chen, Qinjie Cui, Yanjie Yang, Hailan Chen, Michael G. Kong Jan 2016

Intracellular Ros Mediates Gas Plasma-Facilitated Cellular Transfection In 2d And 3d Cultures, Dehui Xu, Biqing Wang, Yujing Xu, Zeyu Chen, Qinjie Cui, Yanjie Yang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

This study reports the potential of cold atmospheric plasma (CAP) as a versatile tool for delivering oligonucleotides into mammalian cells. Compared to lipofection and electroporation methods, plasma transfection showed a better uptake efficiency and less cell death in the transfection of oligonucleotides. We demonstrated that the level of extracellular aqueous reactive oxygen species (ROS) produced by gas plasma is correlated with the uptake efficiency and that this is achieved through an increase of intracellular ROS levels and the resulting increase in cell membrane permeability. This finding was supported by the use of ROS scavengers, which reduced CAP-based uptake efficiency. In …


Quantification Of Blood Flow Velocity Using Color Sensing, Aditya Deepak Sanghani Oct 2015

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 …


The Effects Of Vagus Nerve Stimulation On Neuroinflammation In Epilepsy, Elizabeth A. St. Clair, Gabriel O Albors, Pedro Irazoqui Dr., Amy Brewster Aug 2015

The Effects Of Vagus Nerve Stimulation On Neuroinflammation In Epilepsy, Elizabeth A. St. Clair, Gabriel O Albors, Pedro Irazoqui Dr., Amy Brewster

The Summer Undergraduate Research Fellowship (SURF) Symposium

Epilepsy is a neurological disorder characterized by chronic, unexplainable seizures. Recurring epileptic seizures are associated with long-term structural damage and cognitive deficits, and can even lead to sudden, unexplainable death. Approximately 30% of epilepsy cases are not responsive to medication. Epileptic seizures often induce inflammation in the brain and may increase the frequency of future seizures, resulting in a detrimental cycle. Vagus nerve stimulation (VNS) is a non-pharmaceutical treatment method for epilepsy that has been shown to reduce inflammation in peripheral pathways. The role of VNS in the modulation of neuroinflammation has yet to be demonstrated experimentally. To explore this, …


Nanopulse Generators: Their Design And Application To Cancer Therapy Studies, Daniel P. Wernig Dec 2014

Nanopulse Generators: Their Design And Application To Cancer Therapy Studies, Daniel P. Wernig

Senior Honors Theses

Effective nanopulse generators have become critical in recent decades concerning the study of subcellular affects in response to nanosecond pulsed electric fields. It has been observed that nanosecond duration electric pulses can target intracellular organelles, ultimately leading to cell apoptosis, suggesting the possibility of a new, minimally invasive, low risk cancer therapy methodology. The standard topology for developing a medical nanopulser is the Blumlein “transmission line” approach. This approach relies on the nearly infinitesimal, yet finite amount of time required for an electromagnetic field to propagate down a short transmission line. Prior to design, requirements and constraints must be defined …


Medical Applications Of Mrc, Kyle Thackston, Henry Mei, Pedro Irazoqui Aug 2014

Medical Applications Of Mrc, Kyle Thackston, Henry Mei, Pedro Irazoqui

The Summer Undergraduate Research Fellowship (SURF) Symposium

Consistent powering is a limiting reagent for many medical implants and sensors. Powering in-vivo devices in animal studies requires either transcutaneous wiring (limiting mobility and increasing the chance of infection) or an implanted battery (limited lifetime and limits size of device). Wireless power transfer (WPT) would be able to overcome these challenges and permit the use of more advanced implantable devices in a research setting. Magnetic resonance coupling (MRC), an advanced form of inductive charging, allows good transfer efficiencies over significant air gaps, but works best a specific location and frequency, limiting mobility in animal studies. Using band-pass filter theory, …


Improving Golf Putt Performance With Statistical Learning Of Eeg Signals, Qing Guo Aug 2014

Improving Golf Putt Performance With Statistical Learning Of Eeg Signals, Qing Guo

Graduate Theses and Dissertations

In this thesis, a machine learning based method is proposed to predict the putt outcomes of golfers based on their electroencephalogram (EEG) data. The method can be used as a core building block of a brain-computer interface, which is designed to provide guidance to golf players based on their EEG patterns. The proposed method includes three steps. First, multi-channel 1-second EEG trials were extracted during golfers' preparation of putting. Second, different features are calculated such as correlation coefficient, power spectrum density and coherence, which are used as features for the classification algorithm. To predict golfers' performance, the support vector machine …


Reading And Wirelessly Sending Eeg Signals Using Arduinos And Xbee Radios To Control A Robot, Andrew Paul Simms May 2014

Reading And Wirelessly Sending Eeg Signals Using Arduinos And Xbee Radios To Control A Robot, Andrew Paul Simms

Electrical Engineering Undergraduate Honors Theses

The objective of this project is to develop an EEG device that can read brainwaves from an individual, analyze the data, and use the result to send a wireless signal using Arduinos and XBee Radios to a Boe-bot to perform an action. One of the goals of this project is to read EEG data with a higher sampling frequency than a previously manufactured EEG device. The second part of the project used the device developed to differentiate an individual’s thinking between right and left and then send a simple signal to a robot using an XBee radio to perform an …


Generation Of Bipolar Nanosecond Pulses, Sambasiva Rao Rajulapati Apr 2014

Generation Of Bipolar Nanosecond Pulses, Sambasiva Rao Rajulapati

Electrical & Computer Engineering Theses & Dissertations

Bipolar pulse generation has been studied using transmission line technology, which was mainly used for monopolar pulse generation. In this thesis, low impedance, high current, nanosecond pulse generators were designed, constructed and tested. Five transmission lines were connected in parallel, so the impedance was 10 n. The transmission lines were switched by a spark gap switch operated in air. The closing of the switch creates a matched condition on one side of the transmission lines and a short circuit on the other side of the transmission lines. When the transmission lines are precharged, one of the two waves in opposite …


Computational Modeling To Evaluate Helical Electrode Designs For Use In Vagus Nerve Stimulation, Anthony W. Cowley Jun 2013

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 …


Novel Bioelectrical Measurement Using A Digital Biopotential Monode, Mark Nolan, Edward Burke, Eugene Coyle Jan 2011

Novel Bioelectrical Measurement Using A Digital Biopotential Monode, Mark Nolan, Edward Burke, Eugene Coyle

Conference Papers

In conventional biopotential recording, two or more electrodes are placed on the body. A unipolar lead records the time-varying electrical potential at a single point (relative to a reference potential) via one signal electrode. A bipolar lead records the time-varying potential difference between two points via two signal electrodes. In each case, the signal electrodes are connected to high impedance amplifier inputs, while an additional electrode provides a low-impedance path between the amplifier and human subject. Bipolar leads are usually preferred since interference appearing at both signal electrodes can be eliminated using an instrumentation amplifier with high CMRR. A drawback …


Human Osteoblast Proliferation In Culture Following A Nanosecond Pulsed Electric Field (Nspef), Leonard Joseph Carinci Jr. Apr 2010

Human Osteoblast Proliferation In Culture Following A Nanosecond Pulsed Electric Field (Nspef), Leonard Joseph Carinci Jr.

Biological Sciences Theses & Dissertations

Osteoblasts are mononucleate bone forming cells responsible for the deposition of new bone. Application of mechanical stress on bone reveals its ability to produce and release electric potentials across the cell membrane called piezoelectricity. The electric potentials produced in response to mechanical stress may have a direct correlation on osseous cells and the signaling pathways that regulate proliferation. Nanosecond pulsed electric fields (nsPEFs) are high intensity, ultrashort pulses which have the ability to maintain the integrity of the cell membrane by avoiding traditional electroporation. We delivered 8 nsPEFs (0.5 Hz) of a 25 kV/cm or 35 kV/cm electric field strength …


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 …


Time-Frequency Analysis Of Intracardiac Electrogram, Erik Brockman Jun 2009

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 …


Analysis Of Electroencephalogram Signals For The Identification Of Mental Tasks, My Thy Thi Tran Apr 2009

Analysis Of Electroencephalogram Signals For The Identification Of Mental Tasks, My Thy Thi Tran

Electrical & Computer Engineering Theses & Dissertations

Electroencephalogram (EEG) signals can be used for implicit communication such as to control robots or medical equipment by brain activity or to detect an individual's intentions of committing premeditated crimes. An EEG based brain-computer interface allows paralyzed patients to express their thoughts. However, biological and technical artifacts heavily interfered with EEG signals due to blinking of the eyes, muscle activities and line noise. Sometimes the noise interference due to signal artifacts becomes more prominent than the information content. This thesis investigates novel feature extraction methodologies in EEG signals to represent different thought processes and employs neural network-based pattern classification techniques …


Microfabrication Of An Optical Chamber For Exposing Living Cells To Pulsed Electric Fields, Saleh Sheikh Oct 2007

Microfabrication Of An Optical Chamber For Exposing Living Cells To Pulsed Electric Fields, Saleh Sheikh

Electrical & Computer Engineering Theses & Dissertations

I have fabricated a chamber which enables the application of Nanosecond Pulsed Electric Fields (nsPEFs) to living cells while monitoring their real time fluorescence with an inverted microscope. The No. I thickness (150µm nominal) coverslip glass substrate used for fabrication allows the use of high numerical aperture oil immersion objectives for imaging intracellular organelles. Electrodes are fabricated by first evaporating a chromium adhesion layer, followed by a nickel seed layer. Subsequently, an ultra-thick positive photoresist is applied and patterned to create a 30µm thick electroplating mold. The electrodes are then electrodeposited into the mold from a nickel sulfamate plating bath. …


Simulation And Modeling Of Nerve Impulse Propagation And Its Blockage By External Electrical Stimulation, Nidhi Nahar Apr 2007

Simulation And Modeling Of Nerve Impulse Propagation And Its Blockage By External Electrical Stimulation, Nidhi Nahar

Electrical & Computer Engineering Theses & Dissertations

The electric nature of biological tissues permits the transmission of signals for information and for control and is, therefore, of vital importance for life. The latest scientific achievements and nanoscale probing techniques now allow scientists to research at the subcellular level by measuring the electric current flows through a single ion channel of the cell membrane with the patch-clamp method. With the latter approach, the effects of electrical stimulation can be quantified, understood, and applied to molecular biology and the development of medical diagnostic and therapeutic methods.

In this thesis, the Hodgkin-Huxley approach for unmyelinated fibers, coupled with a transmission …


The Effects Of Ultrashort Pulsed Electric Fields On The Fluorescent Molecule Bodipy Fl C5 Ceramide, Rachael Sara Shevin Oct 2006

The Effects Of Ultrashort Pulsed Electric Fields On The Fluorescent Molecule Bodipy Fl C5 Ceramide, Rachael Sara Shevin

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric fields are able to manipulate internal cell organelles by taking advantage of the small but finite time required for charge to establish across a capacitive barrier. Pulsed electric fields also affect macromolecular structures such as enzymes and proteins. Application of a single nanosecond pulsed electric field decreases the fluorescence of a commercially available biological dye Bodipy FL C5 Ceramide, used to observe the Golgi apparatus of living cells. The effect is seen when the fluorophore is exposed to an electric field both in vitro and when incorporated into the Golgi of a living Jurkat cell. Observation …


Temporal Calcium Response Of Jurkat Cells To Nanosecond Pulsed Electric Fields, Shaka Shakar Scarlett Jul 2006

Temporal Calcium Response Of Jurkat Cells To Nanosecond Pulsed Electric Fields, Shaka Shakar Scarlett

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric fields (nsPEF) of megavolt per meter field strengths can interact with subcellular structures [1] and consequently trigger a variety of biological events. The exposure can induce apoptosis, as well as an array of differential "sub-lethal effects." One of the most sensitive and immediate responses is the increase in intracellular calcium concentration in pulsed cells [2], [3][4].We investigated the response of Jurkat cells (a human leukemic cell line) to nsPEFs of 60 ns duration and field strengths from 25 tol00 kV/cm. The development of the induced calcium response in individual cells was studied by spinning-disc confocal microscopy with …


Time Domain Dielectric Spectroscopy Analysis Of Hl-60 Cell Suspensions After Microsecond And Submicrosecond Pulsed Electric Fields, Allen Laurence Garner Oct 2003

Time Domain Dielectric Spectroscopy Analysis Of Hl-60 Cell Suspensions After Microsecond And Submicrosecond Pulsed Electric Fields, Allen Laurence Garner

Electrical & Computer Engineering Theses & Dissertations

Pulsed electric fields (PEF's) above a certain voltage threshold cause electroporation for microsecond pulses and intracellular effects for submicrosecond pulses. Models describing these effects often depend on the electrical properties of the cell, which are altered by the PEF. Time domain dielectric spectroscopy was used to provide data for these models and to measure changes in the conductivity of HL-60 cell suspensions due to single 50 μs and 10 ns PEF's of the same energy. For 1.1 kV/cm, 50 μs pulses, the conductivity rose within a minute after the pulse and dropped dramatically approximately forty minutes after the pulse. For …