Engineering Commons^™

Neurovascular Catheter Measurement System Development For Process And Design Effect Evaluation, Cathal Tadhg Merz

Theses

Neurovascular guide catheters are used to treat problems affecting blood vessels within the brain through minimally invasive procedures. Catheters are inserted into the patient via their femoral or brachial arteries and manually navigated to the brain to deliver treatment. This procedure replaces the requirement to cut into the patient’s skull and brain tissue but is limited by reduction of blood vessel lumen diameter and increase in tortuosity of blood vessels deep in the brain. During these procedures, catheters can sometimes fail by kinking or fracturing into two pieces. The rate of failure by fracture of a particular neurovascular catheter device …

An Improved Method For Hospital Acquired Pressure Ulcer (Hapu) Prevention, Julia Beekman, Jillian Yeager, Megan Morrissey

Honors Theses

Hospital acquired pressure ulcers (HAPUs), also called bedsores, are damage to the skin and/or underlying tissue caused by prolonged pressure on the bony areas of the body, with around 20% of pressure ulcers occurring in the heel region. Currently, the most common practice for HAPU prevention is arbitrary manual repositioning of patients by nurses every 1-2 hours. The goal of our project was to address HAPUs in the heel region of low mobility patients through an ulceration risk sensing system. Our team has created a wearable ulceration risk assessment system that combines individual patient risk data with real time pressure …

Modified Stent Design For A Coronary Bifurcation Lesion, Abigail Nowell

Biological Sciences Undergraduate Honors Theses

Currently, 18.2 million adults aged 20 and older are diagnosed with Coronary Artery Disease (CAD) (Benjamin et al., 2019). Stenosis is the most common intervention. However, when a patient has a bifurcated artery, treatment becomes more difficult and is often unsuccessful. This project created a new stent and balloon complex that was tested in vitro using a gel phantom artery model. Two separate prototypes have been created and tested so far, with improvements made upon each. Testing is still underway with Prototype 2.

Enhancement Of The Syncardia Total Artificial Heart For Pediatric Use, Margaret Clark, Madison Marks

Williams Honors College, Honors Research Projects

Pediatric patients with disorders and diseases of the heart have limited options with regards to implantable devices. Many of these implants are ventricular assist devices, which is not always suitable for a patient. Total artificial hearts (TAHs) have supported many adult patients until transplantation, and we believe that they could do the same for pediatric patients. SynCardia has the only Food and Drug Administration (FDA) approved TAH devices. Since SynCardia is the only company with FDA approved TAHs, we decided to modify the design of the SynCardia TAH for use in pediatric patients without compromising the function of the current …

Development Of An Astrocyte/Glioma Co-Culture System For Measuring Cellular Dynamics, Urna Kansakar

Doctoral Dissertations

Gliomas are brain tumors that primarily arise from glial cells. Gliomas account for 70% of the brain tumors and they are more prevalent in older adults. About 60% of the people with gliomas experience at least one seizure. Brain tumors can grow and metastasize to neighboring areas, thereby destroying normal brain cells. In a brain tumor microenvironment, both malignant cancer cells and healthy brain cells are present. Studies have shown that astrocytes may have a role in tumor growth in the brain. Monocultures cannot evaluate interactions between two cell types and does not accurately represent in vivo conditions. Thus, a …

Foot Stress And Blood Flow Sensing Under High-Loading During Hip Surgery, Chris Cardenas, Esther Chen, Claire Kingston, Katie Paswaters, Brianna Rodebaugh

Mechanical Engineering

The PolyHIPS team was tasked with integrating sensors into Stryker’s hip arthroscopy boot that monitor blood flow and heel slip during hip surgery. During hip arthroscopy, the femur head is distracted from the acetabulum to create space in the joint for the surgeon to operate. This requires the use of up to 200 lbf. In order to maintain this space, the foot is held tightly in the boot. Complications can result from the foot being held too tightly in the boot during the procedure. The most common complication is neuropraxia, or temporary nerve damage. PolyHIPS proposes a solution that utilizes …

3d Printed Force Transducers For In-Vitro Mitral Valve Chordae Tendineae Force Measurements, Hayley Chandler

Biomedical Engineering Undergraduate Honors Theses

Mitral valve surgery is incredibly prevalent in the United States with more than 40,000 mitral valve surgical procedures annually. Improving the imaging techniques used to diagnose these cases requires validation of 3D models through experimental data such as mechanical properties of the tissue. An essential part of this process for the mitral valve is measuring the force experienced by chordae tendineae. This has been achieved with brass force transducers but using a 3D printed design can have many benefits. In this study, 3D printed miniature c-shaped force transducers comparable to previous metal models were designed and created using Solidworks 2016. …

Increasing Drug Delivery Efficacy Of Drug-Coated Balloons, Alexander Galan, Eric Bidinger, Franco Godoy, Shrusti Patel

Senior Theses

Peripheral artery disease (PAD), the narrowing of peripheral arteries located in areas such as the arms and legs, is a common disease that affects 12% to 20% of people over 65. Numerous therapies have been developed to treat PAD, the most recent technology being drug-coated balloons. Drug-coated balloons release drugs, such as Paclitaxel (PTX), into the arterial wall during balloon angioplasty to locally treat PAD. Current levels of drug transfer from the balloon to the vascular endothelium are at a low 10%-18%. Our Biomedical Engineering Senior Design project aims to increase drug delivery of drug-coated balloons by manipulating the clinically-controllable …

Development Of High Resolution Tools For Investigating Cardiac Arrhythmia Dynamics, Christopher Reed Gloschat

McKelvey School of Engineering Theses & Dissertations

Every year 300,000 Americans die due to sudden cardiac death. There are many pathologies, acquired and genetic, that can lead to sudden cardiac death. Regardless of the underlying pathology, death is frequently the result of ventricular tachycardia and/or fibrillation (VT/VF). Despite decades of research, the mechanisms of ventricular arrhythmia initiation and maintenance are still incompletely understood.

A contributing factor to this lack of understanding is the limitations of the investigative tools used to study VT/VF. Arrhythmias are organ level phenomena that are governed by cellular interactions and as such, near cellular levels of resolution are needed to tease out their …

Compressive Sensing Framework For Mass Spectrometry Data Analysis, Khalfalla Ahmad Kh. Awedat

Dissertations

Mass Spectrometry (MS) data is ideal for identifying unique bio-signatures of diseases. However, the high dimensionality of MS data hinders any promising MS-based proteomics development. The goal of this dissertation is to develop an accurate classification tool by employing compressive sensing (CS). Not only can CS significantly reduce MS data dimensionality, but it also will allow for full reconstruction of original data. The framework developed in this work is based on using L2 and a mixed L2-L1 norms, allowing an overdetermined system to be resolved. The results show that the L2- based algorithm with regularization terms has a better performance …

Plasticity Of The Cortical Representation Of Finger Extensors Induced By Paired Associative Stimulation, Ian Anthony Gerard Lafond

Dissertations

This dissertation first explored associative plasticity of the human motor cortical representation with the use of noninvasive transcranial magnetic stimulation (TMS) paired with peripheral electrical stimulation. Paired Associative Stimulation (PAS) has grown in popularity because of its potential clinical applications. PAS techniques are used in combination with electromyography (EMG) measurements to study cortical excitability and features of hand movement. This work focuses on a cohesive approach to answer central questions about: the ideal mechanism to facilitate cortical plasticity via PAS, the interaction between the behavior performed and type of stimulation delivered to the targeted cortical network and the effects of …

New Design Of Nasogastric Decompression Tube That Incorporates A Self-Cleaning Brushing Mechanism, Nichole Abla, Lindsay Rucker, Paige Schroder

Senior Theses

Many hospitalized patients require the removal of secretions that accumulate in the stomach and must be removed by a nasogastric tube, which unfortunately clogs often. This project outlines the redesign of the nasogastric tube that will ideally prevent nasogastric tube clogging by incorporating a brush mechanism and a contracting tip mechanism, to act as preventative measures against clogging.

Determining The Transport Enhancement Of Sodium Fluorescein In Mechanically-Loaded Canine Tibia, Andrew Joseph Zak

ETD Archive

Quantitative research concerning the impact of mechanical loading on the transport properties of bone has several critical applications. One such application is the effect of a microgravity environment, where the lack of mechanical forces on bone has been shown to negatively impact both growth and repair. A method has been developed in our lab that can potentially allow for the measurement of the effective permeability of large molecules (i.e., 300-15,000 Da in size) in bone tissue under both unloaded and mechanically loaded conditions. In proof-of-concept experiments, previous students have measured the effective diffusivity of the model solute, sodium fluorescein (376 …

Time And Temperature Dependent Surface Tension Measurements Of Responsive Protein-Based Polymer Surfactant Solutions, Hakan Celik

ETD Archive

A three-armed star elastin-like polypeptide (ELP-foldon) has thermoreversible character which exhibits phase separation above a transition temperature (Tt) in physiologic salt concentrations. At lower salt concentration, the ELP-foldon behaves like a thermoresponsive surfactant, exhibiting micelle formation above its Tt. The purpose of this study is characterize the surfactant behavior of the ELP-foldon at air-liquid interface by measuring the surface tension. The surface tension is measured as a function of time for different ELP concentrations from 10 nM to 50 ℗æM and over range of temperatures from 25 to 35 ℗¿ using the axisymmetric drop shape analysis (ADSA). The ADSA is …

Development Of Biomechanical Analysis Techniques For Fatigue Of Transtibial Prosthetic Socket And Pylon Interactions, Thomas Z. Sudbury

Honors Theses

The lack of formal, engineering based information is prevalent in the prosthetic industry. Currently, very few prosthetic manufacturing companies can definitively tell their patients how long their products will last. Because of this lack of information, many amputee patients will experience failure of their transtibial prosthetic device during daily activities. One such failure occurs from the fatigue of everyday use. Fatigue failures originate from the repeated application of certain loading conditions. These repeated loads usually occur for millions of cycles before a transtibial prosthetic catastrophically fails. The purpose of this study is to develop a testing procedure and apparatus that …

Potential Optimal Gait Performance Of Mauch S-N-S Prosthetic Knee Configurations As Predicted By Dynamic Modeling, Chih-Hao Chien

ETD Archive

Patients with prosthetic legs routinely suffer from abnormal gait patterns which can cause health issues and eventually lower the quality of their lives. Despite the half-century advance in the technology of prosthetic knees, from the purely mechanical to microprocessor controlled systems, patient testing suggests that very little progress has been made in the quality of the kinetics and kinematics of amputee gait. Moreover, the cost of microprocessor controlled prosthetic knees may be 10 times more than the purely mechanical knees. While prosthetic knees have become more complex and expensive, it is not proven that the prosthetic knee is a central …

Design Of Recombinant Tenebrio Molitor Antifreeze Protein For Purification Using Elastin-Like Polypeptide Tag, Joongseok Oh

ETD Archive

Fusion protein technologies can aid to improve solubility of recombinant protein from microorganisms and help recombinant protein purification. Elastin-like polypeptides (ELP) as a fusion tag can be utilized to facilitate the purification of recombinant proteins because ELP can provide its thermally responsive behavior to ELP tagged proteins. An ELP tag can be used as the purification carrier through inverse transition cycling (ITC), which is a simple and non chromatographic separation process. The purification through ITC can reduce cost and can be quickly performed compared to other purification methods. However, we further considered ELP tag removal because it may possibly hinder …

Evolutionary Optimization Of Atrial Fibrillation Diagnostic Algorithms, Aref Smiley

ETD Archive

The goal of this research is to introduce an improved method for detecting atrial fibrillation (AF). The foundation of our algorithm is the irregularity of the RR intervals in the electrocardiogram (ECG) signal, and their correlation with AF. Three statistical techniques, including root mean squares of successive differences (RMSSD), turning points ratio (TPR), and Shannon entropy (SE), are used to detect RR interval irregularity. We use the Massachusetts Institution of Technology / Beth Israel Hospital (MIT-BIH) atrial fibrillation databases and their annotations to tune the parameters of the statistical methods by biogeography-based optimization (BBO), which is an evolutionary optimization algorithm. …

Human Motion Analysis With Wearable Inertial Sensors, Xi Chen

Doctoral Dissertations

High-resolution, quantitative data obtained by a human motion capture system can be used to better understand the cause of many diseases for effective treatments. Talking about the daily care of the aging population, two issues are critical. One is to continuously track motions and position of aging people when they are at home, inside a building or in the unknown environment; the other is to monitor their health status in real time when they are in the free-living environment. Continuous monitoring of human movement in their natural living environment potentially provide more valuable feedback than these in laboratory settings. However, …

A Robotic Neuro-Musculoskeletal Simulator For Spine Research, Robb W. Colbrunn

ETD Archive

An influential conceptual framework advanced by Panjabi represents the living spine as a complex neuromusculoskeletal system whose biomechanical functioning is rather finely dependent upon the interactions among and between three principal subsystems: the passive musculoskeletal subsystem (osteoligamentous spine plus passive mechanical contributions of the muscles), the active musculoskeletal subsystem (muscles and tendons), and the neural and feedback subsystem (neural control centers and feedback elements such as mechanoreceptors located in the soft tissues) [1]. The interplay between subsystems readily encourages "thought experiments" of how pathologic changes in one subsystem might influence another--for example, prompting one to speculate how painful arthritic changes …

Scaffold Composition And Architecture Critically Regulate Extracellular Matrix Synthesis By Cardiomyocytes, Arsela Gishto

ETD Archive

Heart failure accounts for over 5 million cases in the U.S. A major onset of this is myocardial infarction, which causes the myocardium to loose cardiomyocytes and transform into a scar tissue. Given that the adult infarcted cardiac tissue has a limited ability to regenerate, alternative methods to restore the damaged area need to be developed. The goal of these approaches is to design an optimal scaffold that can retain and deliver cardiomyocytes at the site of damaged myocardium. This tissue engineering approach would allow cardiac reconstruction by replacing the lost cardiomyocytes, delivering the required biomolecules, as well as remodeling …

Three-Dimensional Kinematic Analysis Using The Xbox Kinect, Robert Matthew Wham

Chancellor’s Honors Program Projects

No abstract provided.

One-Dimensional Radial Diffusion Of Small Molecules (376 Da) In Bone Tissue, Kurt W. Farrell

ETD Archive

The flow of nutrients through any biological tissue is important to maintain homeostasis. If the transport process is understood, medical research teams can better design medications, prosthetic implants, and tissue scaffolds. Additionally, transport rates help physicians to better understand disease states and wound healing, including minor injuries such as breaks and sprains, which will aid in better diagnoses. We developed a novel method that measures the rate of diffusion in vitro, of fluorescein sodium salt. Samples were incubated at 37°C in a 5 CO2 atmosphere for various periods of time. Samples were sliced and analyzed using Image-Pro Plus and MATLAB …

Semi-Automatic Segmentation Of Normal Female Pelvic Floor Structures From Magnetic Resonance Images, Xiaolong Li

ETD Archive

Stress urinary incontinence (SUI) and pelvic organ prolapse (POP) are important health issues affecting millions of American women. Investigation of the cause of SUI and POP requires a better understand of the anatomy of female pelvic floor. In addition, pre-surgical planning and individualized treatment plans require development of patient-specific three-dimensional or virtual reality models. The biggest challenge in building those models is to segment pelvic floor structures from magnetic resonance images because of their complex shapes, which make manual segmentation labor-intensive and inaccurate. In this dissertation, a quick and reliable semi-automatic segmentation method based on a shape model is proposed. …

Spectral Analysis Of Pathological Acoustic Speech Waveforms, Priyanka Medida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biomedical engineering is the application of engineering principles and techniques to the medical field. The design and problem solving skills of engineering are combined with medical and biological science, which improves medical disorder diagnosis and treatment. The purpose of this study is to develop an automated procedure for detecting excessive jitter in speech signals, which is useful for differentiating normal from pathologic speech. The fundamental motivation for this research is that tools are needed by speech pathologists and laryngologists for use in the early detection and treatment of laryngeal disorders. Acoustical analysis of speech was performed to analyze various features …