Biomedical Commons^™

Cyberknife Radiation Modeling: Effects Of Relaxed Translational And Rotational Constraints On Healthy Tissue Irradiation, Sudha Bhavaroop Potineni

Electrical & Computer Engineering Theses & Dissertations

The Cyberknife system is a robotic radio surgery instrument that is used to treat cancers in different parts of the human body. Because of its accuracy and precision, it has become one of the best radio surgery systems in the world. However, even with Cyberknife the treatment time for one session takes from 30 minutes up to 120 minutes depending on the size, shape, and position of the tumor in the human body. In this research, a solution is presented to aid in reducing this long treatment time. An algorithm is developed which simulates the amount of the healthy tissue …

An Investigation Into Ultrasonic Communication For Near-Body Networks, Eric Joshua Escudero Jr., Gursewak Singh Rai

Electrical Engineering

The following report presents a study of body-area, free-space ultrasonic communication system. Two analog communication systems are investigated. The initial communications system setup relies upon the amplitude modulation (AM) techniques to transmit the signal. Such a system is prone to noise since the amplitude of the signal is directly affected by distance and the signal strength will deteriorate. The secondary communication system involves utilizing frequency modulation (FM). This method avoids the issue of losing information due to amplitude deterioration, but encounters delay issues. The main hardware components used in the approach outlined include ultrasonic transducers (UTs) used for both transmitting …

Rfid Techniques For Passive Electronics, Ryan Behr, David Cobos

Electrical Engineering

No abstract provided.

Heart-Rate Monitoring Control System Using Photoplethysmography (Ppg), Wesley Nguyen, Ryan Horjus

Electrical Engineering

No abstract provided.

Transverse Isotachophoresis Using Polyacrylamide Gel Electrodes, Mark P. Stambaugh

Master's Theses

Separation and isolation of a desired analyte from an impure sample solution containing numerous unwanted interfering agents is the first step of nearly every laboratory test performed in medicine and biology. Nucleic acids are often of particular interest to doctors and researchers, and although methods currently exist for their isolation, these procedures are costly in time, man-power, and real-estate. In addition to easing the execution of presently performed tests, mitigation or elimination of these drawbacks would make a large range of currently unperformed tests both practical and feasible.

This thesis presents a microfluidics-based approach to the isolation of nucleic acids …

Universal Engineering Programmer – An In-House Development Tool For Developing And Testing Implantable Medical Devices In St. Jude Medical, Khoa Tat Do

Master's Theses

During development and testing of the functionality of the pacemaker and defibrillator device, engineers in the St. Jude Medical Cardiac Rhythm Management Division use an in-house development tool called Universal Engineering Programmer (UEP) to ensure the device functions as expected, before it can be used to test on an animal or a human during the implantation process.  In addition, some applications of UEP are incorporated into the official releases of the device product.  UEP has been developed and used by engineers across departments in the St. Jude Medical Cardiac Rhythm Management Division (CRMD).  This thesis covers the flexible and reusable …

Radio-Frequency Breast Cancer Imaging Results For A Simplified Cylindrical Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonietta D'Alterio, Max Ammann, Rocco Pierri

Conference Papers

Microwave imaging is a pervasive research field and
is useful in numerous applicative diagnostic noninvasive contexts. This paper focuses on two aspects. First, we perform a numerical investigation to assess the role played by fundamental parameters (i.e. number of sensors, operating frequency bandwidth) on cancer detection. To this end, a simplified cylindrical phantom probed by ideal two-dimensional dipoles (i.e. infinitely long along the axis of invariance) is considered. Second, in order to focus on the role of the antennas, we analyze, still by numerical simulations and for a simplified breast model, how performances vary when a realistic antenna is adopted.

Sar Map Of Gel Phantom In A 64mhz Mri Birdcage By Fiber-Optic Thermometry And Fdtd Simulation, Chirag Mukesh Patel

Master's Theses

As implantable medical devices are being used more often to treat medical problems for which pharmaceuticals don’t suffice, it is important to understand their interactions with commonly used medical modalities. The interactions between medical implants and Magnetic Resonance Imaging machines have proven to be a risk for patients with implants.

Implanted medical devices with elongated metallic components can create harmful levels of local heating in a Magnetic Resonance Imaging (MRI) environment [1]. The heating of a biological medium under MRI is monitored via the Specific Absorption Rate (SAR). SAR, defined as power absorbed per unit mass (W/kg), can be calculated …

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 …

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …

Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx acts as the sound source, providing a quasi-periodic excitation of the vocal tract. Following a total laryngectomy, some people speak using an electrolarynx which employs an electromechanical actuator to perform the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the monotonic sound emitted, the need for a free-hand to operate the device, and the difficulty experienced by many laryngectomees in adapting to its use. One improvement to the electrolarynx, which clinicians and users frequently suggest, is the provision of a convenient hands-free control facility. This would allow more natural use of …

Hybrid Sensing And Adaptive Control For Direct Brain Actuation Of Artificial Limbs, Christopher Aasted

Electronic Theses and Dissertations

Developing a non-invasive direct brain control of artificial limbs is both challenging and desirable. Such a sensory and control system, if successful, will have a profound impact on the disabled. In this dissertation, we present the design and development of a non-invasive, hybrid sensory system, which uses near-infrared spectroscopy (NIRS) and electroencephalography (EEG) to measure brain activity with simultaneous electromyography (EMG) to provide feedback data in a healthy limb. Through the combination of these sensory techniques, we have successfully trained a control system capable of mapping brain activity onto muscle actuation. The design of a control algorithm capable of automatic …

Spatio-Temporal Cardiac Pacing Sites Localization And Time Varying Pericardium Potential Maps Projection Using Ecg Precordial Leads And A Single Moving Dipole Model, Jaime R. De La Cruz

Open Access Theses & Dissertations

A novel non-invasive method for the spatiotemporal localization of the sites of strongest cardiac activity, and for the creation of time varying Pericardium Potential Maps (PPM), with the use of patients' ECG precordial leads, is proposed in this Thesis study. Compared to previous studies, which analyze electrocardiograms in either time domain or spatial domain, the proposed method has the advantage of a simultaneous spatiotemporal electrocardiograph analysis and a 3-D visualization of pericardium potentials maps, as well as, the pericardium surface polarization patterns during the cardiac cycle. The spatial properties added to the electrocardiogram allow for the analysis of specific regions …

On Improving Electrooculogram-Based Computer Mouse Systems: The Accelerometer Trigger, Johnalan Keegan, Edward Burke, James Condron, Eugene Coyle

Conference Papers

Eye tracking is a well-established method of computer control for profoundly paralysed people (Anson et al., 2002). Cameras are commonly used to track eye movements (Morimoto et al., 2005) but one alternative is the bioelectrical signal known as the electrooculogram (EOG). There are some EOG mouse control systems that facilitate the use of GUI applications, but certain actions, which are straightforward using a conventional mouse, remain impossible. Unless the eyes are tracking a target, they move in saccades (jumps), making it impossible to voluntarily trace out smooth trajectories with one's gaze, as would be required to draw a smooth curve. …

Modeling Impulse Oscillometry Data: Using Augmented-Ric And Extended-Ric Respiratory Impedance Model Paramaters To Track Pulmonary Health And Disease, Carlos Domingo Ramos Rocha

Open Access Theses & Dissertations

Respiratory diseases are a great health concern. Early detection of disease could greatly improve quality of life and yet the most common pulmonary function test can be an unreliable diagnostic method, especially in the case of children. A reliable method of detecting and assessing small airway impairment could greatly help with timely diagnosis. This research approaches this problem by taking Impulse Oscillometry (IOS) data and its model-derived parameters and assessing their utility in tracking respiratory function and more specifically, small airway function.

This research first describes the use of electric circuits as models to describe lung properties at distinct regions …

Psychophysical Similarity Based Feature Selection For Nodule Retrieval In Ct, Ravi K. Samala

Open Access Theses & Dissertations

The emerging paradigms in cancer research indicate the need for a multi-perspective and multi-modal screening approach for early lung cancer diagnosis to increase the probability of clinical resection. Currently no standalone screening methodology is proved to suffice for a clinical diagnosis. Computed tomography has been proved to present abnormality at an early stage with less impact on survival rate in population studies. Nevertheless, because of its non-invasive characteristic, it can be used for diagnosis, prognosis and visualization of tumor. Studies have shown that Computer aided diagnosis (CAD) as a second reader can perform in a similar capacity as a radiologist. …

Impulse Oscillometric Features And Parsimonious Respiratory Models Track Small Airway Function In Hispanic And Anglo Children, Erika Guadalupe Meraz Tena

Open Access Theses & Dissertations

Asthma is an inflammatory condition of the peripheral (small) airways resulting in airway hyper-reactivity and, among other symptoms, airflow obstruction. It is the most prevalent chronic respiratory disease in children. Reliable and patient-friendly instruments and methods are required to help pulmonologists accurately detect asthma and Small Airway Impairment (SAI) with acceptable clinical accuracy, specificity and sensitivity. Impulse Oscillometry System (IOS) based on the Forced Oscillation Technique (FOT) has been successfully used to measure lung function in children with a high degree of sensitivity and specificity to SAI and Asthma. IOS is a patient-friendly lung function to measure the mechanical impedance …

An Investigation Into The Effect Of Blood Glucose Level Changes On Lf/Hf Parameter Of Hrv Signal In Non-Diabetic And Diabetic Individuals, Reza M. Amanipour

Open Access Theses & Dissertations

The analysis of time duration between consecutive R waves of electrocardiogram (ECG) is a standard method to evaluate the variations in heart rate. The physiological literature reveals that blood glucose levels modulate the autonomic nervous system (ANS) activity and heart rate variability (HRV) is representative of the cardiovascular autonomic function. In the research, an investigation was carried out to investigate the relationship between HRV signal measures derived from ECG and arterial blood glucose changes in five non-diabetic and five diabetic individuals during normoglycemic and mildly hyperglycemic conditions. A CleveLabs BioCapture wireless device was used to acquire ECG signals from ten …

An Apoptosis Targeted Stimulus With Nanosecond Pulsed Electric Fields (Nspefs) In E4 Squamous Cell Carcinoma, Wei Ren, Stephen J. Beebe

Bioelectrics Publications

Stimuli directed towards activation of apoptosis mechanisms are an attractive approach to eliminate evasion of apoptosis, a ubiquitous cancer hallmark. In these in vitro studies, kinetics and electric field thresholds for several apoptosis characteristics are defined in E4 squamous carcinoma cells (SCC) exposed to ten 300 ns pulses with increasing electric fields. Cell death was [95% at the highest electric field and coincident with phosphatidylserine externalization, caspase and calpain activation in the presence and absence of cytochrome c release, decreases in Bid and mitochondria membrane potential (Δψm) without apparent changes reactive oxygen species levels or in Bcl2 and Bclxl levels. …

2d Face Database Diversification Based On 3d Face Modeling, Qun Wang, Jiang Li, Vijayan K. Asari, Mohammad A. Karim, Manuel Filipe Costa (Ed.)

Electrical & Computer Engineering Faculty Publications

Pose and illumination are identified as major problems in 2D face recognition (FR). It has been theoretically proven that the more diversified instances in the training phase, the more accurate and adaptable the FR system appears to be. Based on this common awareness, researchers have developed a large number of photographic face databases to meet the demand for data training purposes. In this paper, we propose a novel scheme for 2D face database diversification based on 3D face modeling and computer graphics techniques, which supplies augmented variances of pose and illumination. Based on the existing samples from identical individuals of …