Biomedical Commons^™

Laminar Flow Hood System Design, Sophie Schneider

Electrical Engineering

In 2011 health care costs for transplants were over 12 billion dollars in the United States for evaluation, procurement, facilities use, physicians, and post-transplant check-ups. In 2012 burns hospitalized 40,000 people and over 17,000 people received organ transplants. Sadly, the number of organ donors greatly lags the number of people on the transplant waiting list and the gap has widened over the decades. While preventative health care is extremely important, researching tissue engineering (TE) to treat patients in fatal condition provides alternatives for replacing or repairing a variety of damaged tissue. These alternative treatments can considerably reduce the supply-demand gap …

Development And Evaluation Of Chitosan Particle Based Antigen Delivery Systems For Enhanced Antigen Specific Immune Response, Bhanuprasanth Koppolu

Graduate Theses and Dissertations

Particle-based vaccine delivery systems are under exploration to enhance antigen-specific immunity against safe but poorly immunogenic polypeptide antigens. Chitosan is a promising biomaterial for antigen encapsulation and delivery due to its ability to form nano- and microparticles in mild aqueous conditions thus preserving the antigenicity of loaded polypeptides. The objective of this work is to develop a chitosan particle based antigen delivery system for enhanced vaccine response. Chitosan particle sizes, which ranged from 300 nm to 3 ìm, were influenced by chitosan concentration, chitosan molecular weight and addition rate of precipitant salt. The composition of precipitant salt played a significant …

A Quantitative Analysis Of A Paper-Based, Laser-Defined, Oxygen-Generating Platform For Chronic Wounds, Tiffany L. Huang, Babak Ziaie

The Summer Undergraduate Research Fellowship (SURF) Symposium

Chronic wounds affect 6.5 million patients a year while consuming US$25 billion in health care costs (Sen 2009 Wound Repair Regen.). Despite advances in wound management therapies, modern treatment for chronic wounds still requires continual professional attention and expensive equipment, posing serious practical and financial burdens for the regular patient. To provide an alternative solution, we are developing a low-cost smart bandage platform that integrates actuators and sensors to monitor and treat chronic wounds. One component of the integrated platform is an oxygen-generating module. It is a polydimethylsiloxane (PDMS) based microfluidic device fabricated on a parchment paper substrate that …

Footwear Antennas For Body Area Telemetry, Domenico Gaetano, Patrick Mcevoy, Max Ammann, Jacinta Browne, Louise Keating, Frances Horgan

Articles

Antennas designed to link footwear sensors within body centric networks are introduced with two small UWB antennas, one directional and another quasi-omnidirectional. The radiating characteristics are evaluated for three positions on a sample sports shoe using a detailed simulation model and measurements with a homogenous foot phantom. Antenna performance is assessed for resilience to close proximity loading by the footwear materials and the phantom foot.

Developing Mhealth Solutions For Natural Family Planning, Md Miftah Uddin

Master's Theses (2009 -)

Natural Family Planning (NFP) is a method to help couples determine the fertile and infertile times of a woman’s menstrual cycle with natural indicators of fertility. NFP methods have advantages over other methods of family planning. Proper use of NFP methods also ensures high effectiveness (close to 98%) in helping couples avoid pregnancy. However, very few physicians prescribe NFP to their patients due to lack of credibility to the fertility methods and lack of access to NFP knowledge. The Marquette University College of Nursing Institute for Natural Family Planning has been researching for many years to increase knowledge and efficiency …

Altered Cholesterol Metabolism In Human Cancers Unraveled By Label-Free Spectroscopic Imaging, Shuhua Yue

Open Access Dissertations

Despite tremendous scientific achievements, cancer remains the second leading cause of death in the United States. Metabolic reprogramming has been increasingly recognized as a core hallmark of cancer. My dissertation work identified novel diagnostic markers and therapeutic targets for human cancers through the study of cholesterol in cancer cells.

Enabled by label-free Raman spectromicroscopy, we performed the first quantitative analysis of lipogenesis at single cell level in human patient cancerous tissues. Our imaging data revealed an unexpected, aberrant accumulation of esterified cholesterol in lipid droplets of high-grade prostate cancer and metastases, but not in normal prostate, benign prostatic hyperplasia, or …

Effects Of Dip-Coated Films On The Properties Of Implantable Intracortical Microelectrodes, Salah Sommakia

Open Access Dissertations

The successful clinical use of implantable intracortical microelectrodes (ICMs) to treat certain types of deafness, blindness, and paralysis is limited by a reactive tissue response (RTR) of the brain. This RTR culminates in the formation of a tight glial scar and a loss of neuronal density around implanted ICMs, and is accompanied by a decrease in signal to noise ratio and an increase in impedance. While no comprehensive mechanistic understanding of the underlying biology is currently agreed upon in the field, a general consensus exists around a highly volatile acute RTR phase. During this acute phase, the electrical properties of …

Developing A Drug Delivery System For Treatment Of Vocal Fold Scarring, Aaron Michael Kosinski

Open Access Dissertations

Vocal fold scarring is an affliction that results in the formation of a disorganized and stiff extracellular matrix (ECM) with abnormal ECM component densities & structures including a significant increase in collagen deposition. It is caused by improper healing post injury and results in profound changes in the biomechanical properties of the vocal folds impairing their ability to generate a normal mucosal wave during phonation.

Finding an effective treatment for vocal fold scarring has been elusive. Currently, treatments seek temporary solutions that correct glottal incompetence and reduce stiffness caused by the scar through the augmentation of the vocal folds using …

Numerical Techniques For The Noninvasive Assessment Of Material Properties And Stresses In Soft Biomaterials, Kent David Butz

Open Access Dissertations

The noninvasive measurement of finite displacements and strains in biomaterials by magnetic resonance imaging (MRI) may be shown to enable mathematical estimates of stress distributions and material properties within structures of the body such as articular cartilage or the intervertebral disc. Such methods will allow for non-contact and patient-specific modeling in a manner not currently possible with traditional mechanical testing or finite element techniques. Therefore, the objective of this thesis was to develop computational methods incorporating imaging-based measures of deformation, composition, and local microstructure to permit nondestructive analysis of a range of complex biomechanical systems.

Finite strain-based models were developed …

Effects Of Hearing Aid Amplification On Robust Neural Coding Of Speech, Jonathan Daniel Boley

Open Access Dissertations

Hearing aids are able to restore some hearing abilities for people with auditory impairments, but background noise remains a significant problem. Unfortunately, we know very little about how speech is encoded in the auditory system, particularly in impaired systems with prosthetic amplifiers. There is growing evidence that relative timing in the neural signals (known as spatiotemporal coding) is important for speech perception, but there is little research that relates spatiotemporal coding and hearing aid amplification.

This research uses a combination of computational modeling and physiological experiments to characterize how hearing aids affect vowel coding in noise at the level of …

A Novel Multiblock Immersed Boundary Method Enabling High Order Large Eddy Simulation Of Pathological And Medical Device Hemodynamics, Anupindi Kameswararao

Open Access Dissertations

Computational fluid dynamics (CFD) simulations are becoming a reliable tool in understanding disease progression, investigating blood flow patterns and evaluating medical device performance such as stent grafts and mechanical heart valves. Previous studies indicate the presence of highly disturbed, transitional and mildly turbulent flow in healthy and pathological arteries. Accurate simulation of the transitional flow requires high order numerics together with a scale resolving turbulence model such as large eddy simulation (LES). This in turn limits one to use a structured fluid flow solver on which complex, branching arterial domains that are typical in the human blood circulatory system could …

Automated Channel Assessment For Single Chip Medradio Transceivers, Mark Alexander Hillig

Dissertations and Theses

Modern implantable and body worn medical devices leverage wireless telemetry to improve patient experience and expand therapeutic options. Wireless medical devices are subject to a unique set of regulations in which monitoring of the available frequency spectrum is a requirement. To this end, implants use software protocols to assess the in-band activity to determine which channel should be used. These software protocols take valuable processing time and possibly degrade the operational lifetime of the battery. Implantable medical devices often take advantage of a single chip transceiver as the physical layer for wireless communications. Embedding the channel assessment task in the …

Eye "R" Glasses: Development Of An Infrared Sensor System For Detecting The Human Body, Rick Wong

Master's Theses

Throughout the years, sensors have been an integral part of automation, alert, and medical systems. Many of these systems measure physiological characteristics of the human body to alert themselves of their current conditions. Drowsy driver systems, for instance, measure the eyes and facial movements with a camera to determine if the driver is falling asleep at the wheel. Electroencephalography (EEG), electrooculography (EOG), and electromyography (EMG) employ electrodes on the human body to measure electrical activity of a patient’s REM sleep cycle patterns. Pulse oximeters use optical light through a process called photoplethysmography (PPG) to measure heart rate.

As diverse as …

Applied Hw/Sw Co-Design: Using The Kendall Tau Algorithm For Adaptive Pacing, Kenneth W. Chee

Master's Theses

Microcontrollers, the brains of embedded systems, have found their way into every aspect of our lives including medical devices such as pacemakers. Pacemakers provide life supporting functions to people therefore it is critical for these devices to meet their timing constraints. This thesis examines the use of hardware co-processing to accelerate the calculation time associated with the critical tasks of a pacemaker. In particular, we use an FPGA to accelerate a microcontroller’s calculation time of the Kendall Tau Rank Correlation Coefficient algorithm. The Kendall Tau Rank Correlation Coefficient is a statistical measure that determines the pacemaker’s voltage level for heart …

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 …

A Knowledge-Based Clinical Toxicology Consultant For Diagnosing Multiple Exposures, Joel D. Schipper, Douglas D. Dankel Ii, A. Antonio Arroyo, Jay L. Schauben

Publications

Objective: This paper presents continued research toward the development of a knowledge-based system for the diagnosis of human toxic exposures. In particular, this research focuses on the challenging task of diagnosing exposures to multiple toxins. Although only 10% of toxic exposures in the United States involve multiple toxins, multiple exposures account for more than half of all toxin-related fatalities. Using simple medical mathematics, we seek to produce a practical decision support system capable of supplying useful information to aid in the diagnosis of complex cases involving multiple unknown substances.

Methods: The system is automatically trained using data mining …

Design And Fabrication Of Nanofluidic Systems With Integrated Sensing Electrodes For Rapid Biomolecule Characterization, Taylor Bradley Busch

Graduate Theses and Dissertations

A transparent nanofluidic system with embedded sensing electrodes was designed and fabricated by integrating Atomic Force Microscopy (AFM) nanolithography, Focused Ion Beam (FIB) milling and metal deposition, and standard microfabrication processing. The fabrication process started with the evaporation of chrome/gold (Cr/Au) onto a Pyrex 7740 wafer followed by photolithography and wet etching of the microchannels. The wafer was patterned a second time to form Au microelectrodes with 15-45 micrometer separation gaps in the nanochannel region. Sensing electrodes (up to one micron wide) were then deposited using FIB to bridge the gaps. The nanochannels were realized through both AFM nanolithography and …

The Geometry And Sensitivity Of Ion-Beam Sculpted Nanopores For Single Molecule Dna Analysis, Ryan Connor Rollings

Graduate Theses and Dissertations

In this dissertation, the relationship between the geometry of ion-beam sculpted solid-state nanopores and their ability to analyze single DNA molecules using resistive pulse sensing is investigated. To accomplish this, the three dimensional shape of the nanopore is determined using energy filtered and tomographic transmission electron microscopy. It is shown that this information enables the prediction of the ionic current passing through a voltage biased nanopore and improves the prediction of the magnitude of current drop signals when the nanopore interacts with single DNA molecules. The dimensional stability of nanopores in solution is monitored using this information and is improved …

Design And Testing Of Novel Mouthguard With Intermediate Nitinol And Foam Layers, Adam Kessler

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is the aim of this study to investigate a novel mouthguard design that incorporates the use of a nickel-titanium (Nitinol) layer and thin foam layer in addition to EVA layers. It is thought that the Nitinol layer can distribute the force of an impact and that the thin foam layer may absorb this distributed force better than a solid EVA mouthguard of the same thickness. Rectangular, flat coupons representative of several mouthguard configurations were constructed for testing using an instrumented drop-weight impact tower. The coupon configurations include a control made of laminated EVA, a group of laminated EVA and …

Closed Loop Control Of A Cylindrical Tube Type Ionic Polymer Metal Composite (Ipmc), Benjamin Mead

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this research is to provide a framework for the integration of tube type, cylindrical Ionic Polymer Metal-Composite (IPMC) into conventional devices. IPMCs are one of the most widely used types of electro-active polymer actuator, due to their low electric driving potential and large deformation range. For this research a tube type IPMC was investigated. This IPMC has a circular cross section with four separate electrodes on its surface and a hole through the middle. The four electrodes allow for biaxial bending and accurate control of the tip location. One of the main advantages of using this type …

Enhanced Diagnostic Accuracy Of Mammograms On A Mobile Device, Sharanya Padmanabhan

Open Access Theses

With the death of a woman every 13 minutes in the US, and one every minute worldwide, due to breast cancer, the need for early detection cannot be overstated. Mammography is a boon for both early detection and screening of breast tumors. It is an imaging system that uses low dose (9mrem) x-rays for examining the breasts, by the electrons reflected from the tissues (thermoelectric effect). However, there are 20% false positives and 10% false negatives in current practice. Hence, there is a critical need for enhancing the accuracy of these mammograms. Towards this, this thesis was aimed at enhancing …

Modeling Tools For Conformal Orthotic Devices, Steven David Riddle

Open Access Theses

The purpose of this thesis is to advance the design of conformal orthotic devices through the development of two modeling tools to address knowledge gaps in the field.

The field of human orthotics has been continually troubled by identifying successful methods of harnessing devices to the body. Past orthotics have utilized a rigid framework with minimal degrees of freedom (DOFs) driven by hard actuators attached to the body at select anchor points. Many devices design the structure and anchor points such that they reduce the degrees of freedom of a targeted joint, limiting the user's mobility and often causing the …

Using Multi-Processors To Reconstruct Images With Proton Computed Tomography, Chenwei Xu

Theses Digitization Project

This project will employ the use of multi-processor technology to reconstruct image data as fast as possible. Two-dimensional image reconstruction technique reconstructs images by solving a linear equation: A x x =b, where A is the path matrix of proton histories, b is electron matrix of the image, and x is the matrix of image. One row in matrix A represents one beam. Matrix A consists of a number of beam projections to the image, and each projection consists of a number of beams. Contains source code.

Detection Of Brain Abnormalities In Football Players Through Diffusion Weighted Imaging, Allan Emilio Diaz Gaez

Open Access Theses

Depression and cognitive impairment are commonly found in retired football players. Although they receive high magnitude hits to the head, the majority of the hits are sub-concussive, resulting in no clinical symptoms. Recent work using functional magnetic resonance (fMRI) and neurocognitive testing confirms that blows, causing changes in brain function, might not necessarily result in clinical diagnosis of concussion. Furthermore, cognitive deficiency in football players may be attributed to repetitive sub-concussive blows to the head. Diffusion weighted imaging (DWI) has previously been utilized to detect white matter (WM) abnormalities in mild traumatic brain injury (mTBI) patients, including those who have …

Sediment And Nutrient Behaviour On The River Bandon, Ireland, S. T. Harrington, Joseph R. Harrington

Conference Papers

This paper presents aspects of sediment and nutrient behaviour on the River Bandon which is located in the South Western River Basin District in Ireland; it is a relatively large sized river catchment in an Irish context with a catchment area of 608 km2. The river catchment is primarily agricultural with some pockets of urban development. The river is prone to flooding on stretches, features a number of special areas of conservation and is distinguished by both suspended and bed load transport. Continuous monitoring of turbidity commenced in February 2010. Manual sampling and testing for suspended sediment concentration and a …

Study Of The Effects Of Changing Physiological Conditions On Dielectric Properties Of Breast Tissues, Abas Sabouni, Camerin Hahn, Sima Noghanian, Edward Sauter, Tim Weiland

Electrical Engineering Faculty Publications

This paper addresses the changes in the physical characteristics (temperature and water/blood content) of breast tissue under different physiological conditions. We examined ex vivo specimens of breast tissue excised at the time of surgery to study the effects of physiological conditions on dielectric properties. We observed that the dielectric properties strongly depend on tissue physiological state. When the biological tissues undergo physiological changes, such as those due to disease or those induced by external changes such as variations in the environmental temperature, the microscopic processes deviate from their normal state and impact the overall dielectric properties. This suggests that microwave …

Inkjet Based Personalized Screening Platform For Cancer Therapy, Jorge Ivan Rodriguez

Open Access Theses & Dissertations

The new paradigm of personalized medicine is beginning to affect clinical practice. In particular, many of the advances in genomics and proteomics have made personalized screening and therapeutic inventions possible. On chip, cellomics approaches to screening and intervention are becoming more commonplace. Cancer therapies may benefit from the rise in `-omics' technologies. In addition, the availability of rapid screening data is crucial to mitigate cancer propagation and increase the possibility of patient recovery. This study is an endeavor to develop a cellomic anticancer drug screening process based on inkjet printing. Previous research has demonstrated that inkjet based screening can reliably …

Role Of Microrna-155 In A Mouse Model Of Colon Cancer., Claire Mitchell Midyette

Theses and Dissertations

Colorectal cancer remains the third most common malignancy and the fourth most common cause of cancer mortality worldwide. Dysregulated miRNA levels are associated with several types of malignancies and may serve as important biomarkers and/or therapeutic targets in colorectal cancer. We examined the role of miRNA-155 on tumorigenesis and associated symptoms using a well-characterized mouse model of colorectal cancer. C57BL/6 wild-type mice and miRNA-155-/- mice (n=7-13 group) were given a single injection of AOM (10mg/Kg) followed by 3 cycles of DSS (2% in the water for 1 week followed by 2 weeks of plain water). A C57BL/6 wild-type group that …

Assessment And Evaluation Of The Dynamic Behavior Of Muscles With Special Reference To Subjects With Diabetes Mellitus, Jorge Garza-Ulloa

Open Access Theses & Dissertations

Diabetes mellitus (simply diabetes) is a group of metabolic diseases in which a person has high blood sugar, either because the body does not produce enough insulin, or because cells do not respond to the insulin that is produced. Each year, the costs of diabetes rise. Diabetes and its complications cost our national economy. Two new methods are proposed to measure the diabetes implications in the muscles of lower body: Muscle energy expenditure analysis based on the detection of muscle transition-to-fatigue, and Natural Fuzzy logic method for differential analysis in muscle/joint. Then the results are compared with the traditional method …

Optimization Of Bioprinting Process Using Design Of Experiments (Doe) And Taguchi Method, Maria Veronica Gonzalez

Open Access Theses & Dissertations

At this time there is a need for new fabrication techniques for engineering complex biological structures related to regenerative medicine, in vitro tissue analysis, and pharmaceutical testing with the purpose of placing specific cells in specific target locations. Right now, there is no enough conventional cell seeding methods that can achieve it. In order to achieve it, bio-fabrication, which is a delivery mechanism capable of placing biomaterials, cells, and bioactive macromolecules in specific target locations, comes to play an important role in this area. Among different approaches, bioprinting is one of the most useful processes that use drop-on-demand delivery mechanisms …