Biomedical Commons^™

Galvanic Vestibular Stimulation Applied To Flight Training, Joel D. Hanson

Master's Theses

Between 1994 and 2003 spatial disorientation resulted in at least 202 aircraft

accidents, 184 of them resulting in fatalities. Galvanic Vestibular Stimulation (GVS)

provides a cost effective and safe way to simulate spatial disorientation and

potentially test pilot’s vestibular system prior to aircraft operation. This experiment

investigates the use of GVS as an indicator of motion sensitivity and explores the

effects of GVS on flight simulation performance. Bilateral bipolar rectangular pulse

electrical stimulations were given to subjects via skin-mounted electrodes placed over

each mastoid process to stimulate the vestibular system with roll and yaw sensations.

Two studies were conducted in …

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 …

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

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 …

An Electrooculogram-Based Binary Saccade Sequence Classification (Bssc) Technique For Augmentative Communication And Control, Johnalan Keegan, Ted Burke, James Condron

Conference Papers

In the field of assistive technology, the electroocu-logram (EOG) can be used as a channel of communication and the basis of a man-machine interface. For many people with severe motor disabilities, simple actions such as changing the TV channel require assistance. This paper describes a method of detecting saccadic eye movements and the use of a saccade sequence classification algorithm to facilitate communication and control. Saccades are fast eye movements that occurs when a person's gaze jumps from one fixation point to another. The classification is based on pre-defined sequences of saccades, guided by a static visual template (e.g. a …

Adjacent Slice Prostate Cancer Prediction To Inform Maldi Imaging Biomarker Analysis, Shao-Hui Chuang

Electrical & Computer Engineering Theses & Dissertations

Prostate cancer is the second most common type of cancer among men in the U.S. [1]. Traditionally, prostate cancer diagnosis is made by the analysis of prostate-specific antigen (PSA) levels and histopathological images of biopsy samples under microscopes. Proteomic biomarkers can improve upon these methods. MALDI molecular spectra imaging is used to visualize protein/peptide concentrations across biopsy samples to search for biomarker candidates. Unfortunately, traditional processing methods require histopathological examination on one slice of a biopsy sample while the adjacent slice is subjected to the tissue destroying desorption and ionization processes of MALDI. The highest confidence tumor regions gained from …

Brain Tumor Progression Assessment Using Multiple Mri Volumes, Yufei Shen

Electrical & Computer Engineering Theses & Dissertations

Predicting and assessing tumor progression is important in brain tumor treatment. We attempt to use machine learning techniques to achieve consistency in assessing brain tumor progression. This thesis presents a prediction method of brain tumor progression by exploring a large MR database, which contains two patients ' complete records covering all their visits in the past two years. All ten MRI series, namely, apparent diffusion coefficient (ADC) , diffusion tensor imaging (DTI) , fractional anisotropy (FA), fluid attenuated inversion recovery (FLAIR), max eigenvalue (MAX), mid eigenvalue (MID), min eigenvalue (MIN) , post-contrast T₁-weighted, T₁- weighted, and …

Effects Of Low-Temperature Atmospheric Pressure Plasma On Streptococcus Mutans, Margaret Farrer Lemaster

Dental Hygiene Theses & Dissertations

The recent emergence of low temperature atmospheric pressure plasma (LTAPP) technology has led researchers to explore biomedical applications. The present study set out to determine if LTAPP has the ability to inactivate dental caries causing bacteria, specifically Streptococcus mutans. Methods: A total of 90 samples were processed. Seventy-two samples of S. mutans at 1: 100 dilution in BHI broth were exposed to LTAPP for various time intervals (60, 120, 180, 300 seconds). Eighteen control samples were plated but not exposed to LTAPP. Samples were plated on Mi tis salivarius (MS) agar and incubated 48 hours at 37° C. Colony …

A Hybrid Biofuel Cell Based On Electrooxidation Of Glucose Using Ultra-Small Silicon Nanoparticles, Yongki Choi, Gang Wang, Munir H. Nayfeh, Siu-Tung Yau

Electrical and Computer Engineering Faculty Publications

The ultra-small silicon nanoparticle was shown to be an electrocatalyst for the electrooxidation of glucose. The oxidation appeared to be a first order reaction which involves the transfer of 1 electron. The oxidation potential showed a low onset of −0.4V vs. Ag/AgCl (−0.62V vs. RHE). The particle was used as the anode catalyst of a prototype hybrid biofuel cell, which operated on glucose and hydrogen peroxide. The output power of the hybrid cell showed a dependence on the enzymes used as the cathode catalyst. The power density was optimized to 3.7μW/cm² when horseradish peroxidase was …

Lifetime Estimation Of Wireless Body Area Sensor Network For Patient Health Monitoring, Frank Agyei-Ntim

Electronic Theses and Dissertations

Wireless Body Area Sensor Networks (WBASN) is an emerging technology which utilizes wireless sensors to implement real-time wearable health monitoring of patients to enhance independent living. These sensors can be worn externally to monitor multiple bio-parameters (such as blood oxygen saturation (SpO2), blood pressure and heart activity) of multiple patients at a central location in the hospital.

In health monitoring, the loss of critical or emergency information is a serious issue so there is a concern for quality of service which needs to be addressed. It is important to have an estimate of the time the first node will fail …

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 …

Computational Modeling Of The Internal Structure In The Breast, Jordan Greenlee

Electrical Engineering Undergraduate Honors Theses

Many researchers who are using microwave modality in the area of breast cancer detection employ oversimplified models of the internal structure of the breast. Use of engineered or biologically inaccurate models could render inaccurate results. Therefore, a mathematical biological model is implemented in this work and aims to bridge the gap between biologists and engineers. The results of the proposed breast duct model show that older women have smaller breast ducts leading to less dense breasts, which is in agreement with medical knowledge. Also, younger women have larger breast ducts leading to more dense breasts which are consistent with the …

Low Voltage, Low Power, Bulk-Driven Amplifier, Shama Huda

Electrical Engineering Undergraduate Honors Theses

The importance of low voltage and low powered electronics is increasing with advances in medical electronics. This branch of electronics specifically requires low voltage and low power to make efficient innovative medical equipment. Low power electronics are also desirable because it conserves energy and power. This paper proposes a design of a differential in - differential our amplifier that uses a bulk-driven differential pair for the input pair. In addition, it also used bulk-driven current mirrors for the tail current sink and the active loads. The bulkdriven technique helps to achieve the low voltage design. 90nm CMOS technology was considered …

Preliminary Study Based On The Ddscat Software To Explore Increasing The Contrast Of Breast Tumors For Microwave Imaging, Rachel Megee

Electrical Engineering Undergraduate Honors Theses

Microwave technology is being researched for its capabilities to detect breast tumors less painfully and at earlier stages. It is necessary to have a large contrast between cancerous and healthy tissue when the microwaves are reflected off the breast tissue. To model the increasing contrast between cancerous breast tissue and healthy breast tissue, the DDSCAT code is investigated for its capabilities and analyzed for its accuracy in scattering calculations. The DDSCAT is used to model homogenous and inhomogeneous targets. Simulations of the scattering field by the homogeneous and inhomogeneous targets are conducted and compared to Mie theory calculations for accuracy. …

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 …

System Architecture For An Intelligent Implantable Bio-Telemetry Device, Karthik Kumar Nattamai Kumaresan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biotelemetry has long been used for environmental and life science research to study animal populations and behavior. The use of implantable bio-telemetric techniques makes it possible to record and study physiological variables during long-term experiments with a minimum disturbance to the animal. Fully implantable telemetric techniques greatly reduce the risk of infection associated with leads and catheters protruding from the skin. In this research the design and implementation of a completely programmable bio-implantable digital system which can measure two physiological signals extended over a period of time is considered. The proposed system consists of a standalone implantable transmitter unit and …

Optimizing Computer-Aided Colonic Polyp Detection For Ct Colonography By Evolving The Pareto Front, Jiang Li, Adam Huang, Jack Tao, Jiamin Liu, Robert L. Van Uitert, Nicholas Petrick, Ronald Summers

Electrical & Computer Engineering Faculty Publications

A multiobjective genetic algorithm is designed to optimize a computer-aided detection (CAD) system for identifying colonic polyps. Colonic polyps appear as elliptical protrusions on the inner surface of the colon. Curvature-based features for colonic polyp detection have proved to be successful in several CT colonography (CTC) CAD systems. Our CTC CAD program uses a sequential classifier to form initial polyp detections on the colon surface. The classifier utilizes a set of thresholds on curvature-based features to cluster suspicious colon surface regions into polyp candidates. The thresholds were previously chosen experimentally by using feature histograms. The chosen thresholds were effective for …

Application Of Sensor Fusion To Human Locomotor System, John Kweku Avor

Open Access Theses & Dissertations

This research study proposes a multi-sensor data fusion technique to determine the complex interactions between the sensory, muscular and mechanical components of the human locomotor systems (neuromechanics). The object in this work is to demonstrate the viability in using inertial sensors for accurate gait phase determination and to present the acceleration effect specific body segment contributes in order to establish a functional gait. The current method used in determining gait phases consist of combining ground reaction force and angular data, this method is time consuming and cannot be totally reliable. We found out that gait phases can be determined distinctively …

Parameter Optimization For Image Denoising Based On Block Matching And 3d Collaborative Filtering, Ramu Pedada, Emin Kugu, Jiang Li, Zhanfeng Yue, Yuzhong Shen, Josien P.W. Pluim (Ed.), Benoit M. Dawant (Ed.)

Electrical & Computer Engineering Faculty Publications

Clinical MRI images are generally corrupted by random noise during acquisition with blurred subtle structure features. Many denoising methods have been proposed to remove noise from corrupted images at the expense of distorted structure features. Therefore, there is always compromise between removing noise and preserving structure information for denoising methods. For a specific denoising method, it is crucial to tune it so that the best tradeoff can be obtained. In this paper, we define several cost functions to assess the quality of noise removal and that of structure information preserved in the denoised image. Strength Pareto Evolutionary Algorithm 2 (SPEA2) …

Identification Of Human Gait Using Genetic Algorithm Tuned Fuzzy Logic, Abdallah Abdel-Rahman Hassan Mahmoud

Open Access Theses & Dissertations

Data mining is concerned with the discovery of useful hidden information in large databases. Classification is a data mining task producing rules in which a set of attributes in data predict the value of a class attribute. Classifiers usually produce a large number of rules, most of which are not interesting to the user. Rule interestingness is a decisive factor. However, evaluating rule interestingness is challenging as it involves both objective (data-driven) and subjective (user-driven) aspects.

In this research, a fuzzy genetic algorithm is proposed to discover classification rules that are both accurate and interesting. Continuous attributes are fuzzified so …

Exploring Poly(Ethylene Glycol) As A Suitable Material For Peripheral Nerve Regeneration Scaffolds Manufactured By Stereolithography, Nubia Zuverza

Open Access Theses & Dissertations

One of the challenges in tissue engineering is to have spatial and temporal control over the biological elements within a scaffold used to guide regeneration for example of transected nerves. Some of the physical and chemical characteristics to regulate include incorporation of bioactive domains and release of chemical signals. This study presents the use of stereolithography (SL) to incorporate localized domains for cell adhesion in addition to include releasable nerve growth factor (NGF) in the process of building poly(ethylene glycol)diacrylate (PEGda) hydrogel scaffolds. Besides providing sites for cell attachment, an ideal nerve guidance conduit (NGC) should be able to release …

Automatic Diagnosis For Prostate Cancer Using Run-Length Matrix Method, Xiaoyan Sun, Shao-Hui Chuang, Jiang Li, Frederic Mckenzie, Nico Karssemeijer (Ed.), Maryellen L. Giger (Ed.)

Electrical & Computer Engineering Faculty Publications

Prostate cancer is the most common type of cancer and the second leading cause of cancer death among men in US¹. Quantitative assessment of prostate histology provides potential automatic classification of prostate lesions and prediction of response to therapy. Traditionally, prostate cancer diagnosis is made by the analysis of prostate-specific antigen (PSA) levels and histopathological images of biopsy samples under microscopes. In this application, we utilize a texture analysis method based on the run-length matrix for identifying tissue abnormalities in prostate histology. A tissue sample was collected from a radical prostatectomy, H&E fixed, and assessed by a pathologist …