Biomedical Commons^™

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 …

Respiratory Prediction And Image Quality Improvement Of 4d Cone Beam Ct And Mri For Lung Tumor Treatments, Seonyeong Park

Theses and Dissertations

Identification of accurate tumor location and shape is highly important in lung cancer radiotherapy, to improve the treatment quality by reducing dose delivery errors. Because a lung tumor moves with the patient's respiration, breathing motion should be correctly analyzed and predicted during the treatment for prevention of tumor miss or undesirable treatment toxicity. Besides, in Image-Guided Radiation Therapy (IGRT), the tumor motion causes difficulties not only in delivering accurate dose, but also in assuring superior quality of imaging techniques such as four-dimensional (4D) Cone Beam Computed Tomography (CBCT) and 4D Magnetic Resonance Imaging (MRI). Specifically, 4D CBCT used in CBCT …

An Investigation Into Spike-Based Neuromorphic Approaches For Artificial Olfactory Systems, Anup Vanarse, Adam Osseiran, Alexander Rassau

Research outputs 2014 to 2021

The implementation of neuromorphic methods has delivered promising results for vision and auditory sensors. These methods focus on mimicking the neuro-biological architecture to generate and process spike-based information with minimal power consumption. With increasing interest in developing low-power and robust chemical sensors, the application of neuromorphic engineering concepts for electronic noses has provided an impetus for research focusing on improving these instruments. While conventional e-noses apply computationally expensive and power-consuming data-processing strategies, neuromorphic olfactory sensors implement the biological olfaction principles found in humans and insects to simplify the handling of multivariate sensory data by generating and processing spike-based information. Over …

A Wireless, Passive Sensor For Measuring Temperature At Orthopedic Implant Sites For Early Diagnosis Of Infections, Salil Sidharthan Karipott

Dissertations, Master's Theses and Master's Reports

Sensorized implants with embedded wireless, passive temperature sensors were developed for early detection of implant-associated infections. The operation principle of the sensor is based on the hypothesis that infections can lead to an increase in local temperature prior to the rise of body temperature. The sensor was an inductive capacitive (LC) circuit that has been used for monitoring of different parameters wirelessly, often in difficult to access environments. The sensor was fabricated on to an interference screw, which is used for tendon and ligament reconstruction surgeries. In this project, a sensorized interference screw was designed and fabricated by accommodating an …

Implantable Wireless Sensor Networks: Application To Measuring Temperature For In Vivo Detection Of Infections, Praharsh Madappaly Veetil

Dissertations, Master's Theses and Master's Reports

It is has been proven that infection in the body cause a local temperature increase due to localized inflammation. Therefore, a method to provide early diagnostic or long-term tracking of this infection will provide great benefits to patients with diabetic foot ulcers or sickle cell disease, and those receiving hemodialysis where they suffer from a weakened immune system. The goal of this project is to develop an implantable wireless temperature sensor based on a wireless sensor network system for monitoring infections in situ. The analog signals from the thermistors are digitized and wirelessly transmitted to a computer with an ez430-rf2500 …

Algorithm For Premature Ventricular Contraction Detection From A Subcutaneous Electrocardiogram Signal, Iris Lynn Shelly

Dissertations and Theses

Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates from an ectopic focus within the ventricles rather than from the sinus node in the right atrium. This and other arrhythmias are often diagnosed with the help of an electrocardiogram, or ECG, which records the electrical activity of the heart using electrodes placed on the skin. In an ECG signal, a PVC is characterized by both timing and morphological differences from a normal sinus beat.

An implantable cardiac …

An Emg-Based Patient Monitoring System Using Zynq Soc Device, Farhad Fallahlalehzari

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis describes the design, development, and testing of an EMG-based patient monitoring system using the Zynq device. Zynq is a system on chip device designed by Xilinx which consists of an ARM dual cortex-A9 processor as well as an FPGA integrated into one chip. This work also analyzes the performance of image-processing algorithms on this system and compares that performance to more traditional PC-based systems. Image processing algorithms, such as Sobel edge detection, dilation and erosion, could be used in conjunction with a camera for the patient monitoring purposes. These algorithms often perform sub-optimally on processors because of their …

Radiation Therapy And Dosing Material Transport Methodology, Robert O'Brien

UNLV Theses, Dissertations, Professional Papers, and Capstones

A technique is examined here that utilizes high energy beta decays from a short lived radioisotope to treat medical conditions such as shallow cancerous lesions. A major benefit of beta particle interaction in tissue is a fixed penetration depth for the charged particle, with dose limited to the ultimate range of the beta particle. This method improves on some current techniques of radioactive brachytherapy, where "seeds" are placed inside patients through temporary or permanent implantation in order to kill cancerous cells or inhibit growth of tissue. The use of low energy gamma-rays is the most common method of treatment currently …

The Effects Of Cryopreservation On Human Dental Pulp-Derived Mesenchymal Stem Cells, Allison Elaine Tomlin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many studies have demonstrated clinical applications for the use of dental pulp stem cells (DPSC) for the treatment of various conditions. This has driven medical and scientific interest in the collection, isolation and banking of DPSC tissues for research into these potential therapies. Few studies to date have evaluated the viability of DPSC following long-term cryopreservation. The purpose of this study is to evaluate the effects of cryopreservation on dental pulp-derived stem cells (DPSC) viability over a period of three years. Dental pulp-derived stem cells were isolated and cultured from thirty-one healthy teeth. DPSC isolates were assessed for doubling-time and …

Approaches For Capturing Time-Varying Functional Network Connectivity With Application To Normative Development And Mental Illness, Barnaly Rashid

Electrical and Computer Engineering ETDs

Since the beginning of medical science, the human brain has remained an unsolved puzzle; an illusive organ that controls everything- from breathing to heartbeats, from emotion to anger, and more. With the power of advanced neuroimaging techniques, scientists have now started to solve this nearly impossible puzzle, piece by piece. Over the past decade, various in vivo techniques, including functional magnetic resonance imaging (fMRI), have been increasingly used to understand brain functions. fMRI is extensively being used to facilitate the identification of various neuropsychological disorders such as schizophrenia (SZ), bipolar disorder (BP) and autism spectrum disorder (ASD). These disorders are …

Behavior Classification Using Multi-Site Lfp And Ecog Signals, Adam O. Hebb, Hosein M. Golshan, Sara J. Hanrahan, Joshua Nedrud, Mohammad H. Mahoor

Electrical and Computer Engineering: Graduate Student Scholarship

Abstract-Deep Brain Stimulation (DBS) is an effective therapy that alleviates the motor signs of Parkinson’s disease (PD). Existing DBS is open loop, providing a time invariant stimulation pulse train that may generate cognitive, speech, and balance side effects. A closed-loop DBS system that utilizes appropriate physiological control variables may improve therapeutic results, reduce stimulation side effects, and extend battery life of pulse generators. Furthermore, by customizing DBS to a patient’s behavioral goal, side effects of stimulation may arise only when they are non-detrimental to the patient’s current goals. Therefore, classification of human behavior using physiological signals is an …

Gait And Tremor Assessment For Patients With Parkinson’S Disease Using Wearable Sensors, Shyam V. Perumal, Ravi Sankar

Electrical Engineering Faculty Publications

Typically, subjects with Parkinson’s disease (PD) display instances of tremor at an early stage of the disease and later on develop gait impairments and postural instability. In this research, we have investigated the effect of using both gait and tremor features for an early detection and monitoring of PD. Various features were extracted from the data collected from the wearable sensors and further analyzed using statistical analysis and machine learning techniques to find the most significant features that would best distinguish between the two groups: subjects with PD and healthy control subjects. The analysis of our results shows that the …

Synchronization Of Coupled Neurons Via Robust Feedback, Hector Puebla, Ricardo Aguilar-Lopez, Priti Kumar Roy

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Ionic Basis Of Ventricular Action Potentials, Ariel L. Escobar

Science Seminar Series

Dr. Escobar will talk about his cutting-edge approach to understanding molecular mechanisms underlying electrical activity in the heart.

Neural Representation Of Vocalizations In Noise In The Primary Auditory Cortex Of Marmoset Monkeys, Ruiye Ni

McKelvey School of Engineering Graduate Student Theses & Dissertations

Robust auditory perception plays a pivotal function in processing behaviorally relevant sounds, particularly when there are auditory distractions from the environment. The neuronal coding enabling this ability, however, is still not well understood. In this study we recorded single-unit activity from the primary auditory cortex of alert common marmoset monkeys (Callithrix jacchus) while delivering conspecific vocalizations degraded by two different background noises: broadband white noise (WGN) and vocalization babble (Babble).

Noise effects on single-unit neural representation of target vocalizations were quantified by measuring the response similarity elicited by natural vocalizations as a function of signal-to-noise ratio (SNR). Four consistent response …

New Tools For Viscoelastic Spectral Analysis, With Application To The Mechanics Of Cells And Collagen Across Hierarchies, Behzad Babaei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Viscoelastic relaxation spectra are essential for predicting and interpreting the mechanical responses of materials and structures. For biological tissues, these spectra must usually be estimated from viscoelastic relaxation tests. Interpreting viscoelastic relaxation tests is challenging because the inverse problem is expensive computationally. We present here (1) an efficient algorithm and (2) a quasi-linear model that enable rapid identification of the viscoelastic relaxation spectra of both linear and nonlinear materials. We then apply these methods to develop fundamental insight into the mechanics of collagenous and fibrotic tissues.

The first algorithm, which we term the discrete spectral approach, is fast enough to …

Haptic Foot Feedback For Kicking Training In Virtual Reality, Hank Huang, Hong Tan

The Summer Undergraduate Research Fellowship (SURF) Symposium

As means to further supplement athletic performances increases, virtual reality is becoming helpful to sports in terms of cognitive training such as reaction, mentality, and game strategies. With the aid of haptic feedback, interaction with virtual objects increases by another dimension, in addition to the presence of visual and auditory feedback. This research presents an integrated system of a virtual reality environment, motion tracking system, and a haptic unit designed for the dorsal foot. The prototype simulates a scenario of virtual kicking and returns haptic response upon collision between the user’s foot and virtual object. The overall system was evaluated …

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 …

Simultaneous Behavior Onset Detection And Task Classification For Patients With Parkinson Disease Using Subthalamic Nucleus Local Field Potentials, Nazanin Zaker Habibabadi

Electronic Theses and Dissertations

This thesis aims to develop of methods for behavior onset detection of patients with Parkinson's disease (PD), as well as to investigate the models for classification of different behavioral tasks performed by PD patient. The detection is based on recorded Local Field Potentials (LFP) of the Subthalamic nucleus (STN), captured through Deep Brain Stimulation (DBS) process.

One main part of this work is dedicated to the research of various properties and features of the STN LFP signals of several patients' behavior conditions. Features based on temporal and time-frequency analysis of the signals are developed and implemented. Evaluation and comparison of …

Investigation Of Cnt-Induced Escherichia Coli Lysis And Protein Release, Abdollah Mosleh

Graduate Theses and Dissertations

This research investigated the use of carbon nanotubes (CNTs) as a treatment to increase the permeability of a bacterial cell wall. Recombinant Escherichia coli BL21 (DE3) containing a plasmid that expressed Green Fluorescent Protein (GFP) and -lactamase were exposed to CNTs under various levels of agitation for different times. Fluorescence assay for GFP, optical absorbance for -lactamase activity, and Transmission Electron Microscopy (TEM) were used to determine the amount of released protein, and visually examine the permeability enhancement of the cells, respectively. It was found that more -lactamase was present in the culture fluid after treatment with CNTs in a …