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Articles 721 - 750 of 1146

Full-Text Articles in Biomedical Devices and Instrumentation

Utility Of Ultrasound/Photoacoustic Imaging For Accurate Catheter Tracking And Temperature Monitoring During Endovenous Laser Ablation, Ayushi Jharia, Keerthana Palani, Yan Yan Jan 2017

Utility Of Ultrasound/Photoacoustic Imaging For Accurate Catheter Tracking And Temperature Monitoring During Endovenous Laser Ablation, Ayushi Jharia, Keerthana Palani, Yan Yan

Research Opportunities for Engineering Undergraduates (ROEU) Program 2016-17

Laser ablation is a treatment method that uses light energy through a catheter inserted into a vein to induce localized heat to close the diseased blood vessels. Ultrasound (US) imaging has been used for catheter visualization and tracking. US has limitations for tracking the accurate location of the fiber tip inside small perforating veins such as angular dependency and comet tail artifacts. We propose a robust and accurate method for fiber tip tracking using combined US and Photoacoustic (PA) imaging to overcome the existing limitations.


Oxygen Transport In Carotid And Stented Coronary Arteries, Eoin A. Murphy Jan 2017

Oxygen Transport In Carotid And Stented Coronary Arteries, Eoin A. Murphy

Doctoral

Oxygen deficiency, known as hypoxia, in arterial walls has been linked to increased intimal hyperplasia, which is the main adverse biological process causing in-stent restenosis. Stent implantation can have significant effects on the oxygen transport into the arterial wall. Helical flow has been theorised to improve the local haemodynamics and the oxygen transport within stented arteries. In this study an advanced oxygen transport model was developed to assess different stent designs. This advanced oxygen transport model incorporates both the free and bound oxygen contained in blood and includes a shear-dependent dispersion coefficient for red blood cells. In two test cases …


Skintronics: Wireless, Skin-Wearable Electronics For Monitoring Of Electrocardiogram, Matthew B. Piper, Woon-Hong Yeo, Yongkuk Lee Jan 2017

Skintronics: Wireless, Skin-Wearable Electronics For Monitoring Of Electrocardiogram, Matthew B. Piper, Woon-Hong Yeo, Yongkuk Lee

Undergraduate Research Posters

The ECGs I micro-fabricate are designed to be flexible, stretchable and wireless circuits that can be applied to the skin directly. The device is encased in a conformal, silicon-like substrate, that allows the ECG to be attached with the electrodes. Each electrode has been previously measured and verified that it will be correctly placed for an accurate reading. Prototyping this ECG/electrode device allows the user to mount the prototype directly to the patient without having to attach and wire ten other electrodes. This prototype solves the issue that comes about when a doctor, nurse or emergency medical technician must attach …


Formulation And Testing Of Biodegradable Polymeric Coating On Zinc Wires In Cardiovascular Stent Application, Avishan Arab Shomali Jan 2017

Formulation And Testing Of Biodegradable Polymeric Coating On Zinc Wires In Cardiovascular Stent Application, Avishan Arab Shomali

Dissertations, Master's Theses and Master's Reports

Biodegradable and biocompatible poly (L-lactic-acid) (PLLA) coating was applied on a modified zinc (Zn) substrate by dip coating, with the intent to delay the bio-corrosion and slow the degradation rate of zinc substrate. 3-(Trimethoxysilyl) propyl methacrylate (MPS) was used for modification of the zinc substrate for promoting the adhesion between the metallic substrate and the polymer coating. It is hypothesized that the delay in Zn biodegradation could be useful in the first several weeks to prevent the early loss of mechanical integrity of the endovascular stent and to improve the healing process of the diseased vascular site. The PLLA coating …


Characterization Of Polyurethane For Use As Substrate In Nanofiber Sensor For Biomedical Applications, Megan Theaker Jan 2017

Characterization Of Polyurethane For Use As Substrate In Nanofiber Sensor For Biomedical Applications, Megan Theaker

Williams Honors College, Honors Research Projects

The purpose of this project is to begin to determine properties of polymer nanocomposites that make a suitable substrate for nanofiber sensors. In this work, sensitivity of a sodium ion selective sensor constructed with polyurethane was used as a benchmark for comparison with sensors constructed with nylon-6. The sensors were characterized using contact angle and chronoamperometry. Using an ANOVA analysis, the results showed that the multi-walled carbon nanotube type was a significant factor on sensor response both with and without additional functionalization of the polymer by calixarene. The weight percentage of polyurethane in the electrospinning solution was also statistically significant …


Development Of An Electrospun And 3d Printed Cellular Delivery Device For Dermal Wound Healing, Ryan M. Clohessy Jan 2017

Development Of An Electrospun And 3d Printed Cellular Delivery Device For Dermal Wound Healing, Ryan M. Clohessy

Theses and Dissertations

The goal of this research was to develop a system of individualized medicine that could be applied to dermal wounds serving as a wound dressing and synthetic extracellular matrix while delivering stem cells to the wound bed. First, fabrication parameters for electrospinning polymer fibers were determined. This involved evaluating fiber morphology with respect to polymer selection and solution concentration. Next, construct fabrication was examined to produce an integrated void space, or cargo area, suitable to maintain stem cells. In vitro studies to ensure stem cell viability and phenotype were conducted, and results supported the notion that cells could be administered …


Surface Enabled Lab-On-A-Chip (Loc) Device For Protein Detection And Separation, Zhichao Wang Jan 2017

Surface Enabled Lab-On-A-Chip (Loc) Device For Protein Detection And Separation, Zhichao Wang

Dissertations, Master's Theses and Master's Reports

Sensitive and selective chemical/biological detection/analysis for proteins is essential for applications such as disease diagnosis, species phenotype identification, product quality control, and sample examination. Lab-on-a-chip (LOC) device provides advantages of fast analysis, reduced amount of sample requirements, and low cost, to magnificently facilitate protein detection research. Isoelectric focusing (IEF) is a strong and reliable electrophoretic technique capable of discerning proteins from complex mixtures based on the isoelectric point (pI) differences. It has experienced plenty of fruitful developments during previous decades which has given it the capability of performing with highly robust and reproducible analysis. This progress has made IEF devices …


Design Development And Performance Study Of A Novel Assistive Device For Mobility Of Toddlers And Children With Visual Impairments, Joowon Jun Jan 2017

Design Development And Performance Study Of A Novel Assistive Device For Mobility Of Toddlers And Children With Visual Impairments, Joowon Jun

Dissertations and Theses

Being able to see allows mankind tremendous access to learn about the world, and because so much learning comes visually, children with visual impairments are delayed in developing range of skills: learning own languages, doing activities, socializing with peers, and etc. While children with vision can do virtually all the activities and tasks for granted, children with visual impairment require different types of tools or materials to do same tasks most of time. Amongst all the disadvantages that children with visual impairment have, one of the most critical disadvantageous area that visual impairment brings to toddler is learning to walk. …


Altering A Runner’S Foot Strike Using A Modified Elliptical Trainer, Daniel Shull Jan 2017

Altering A Runner’S Foot Strike Using A Modified Elliptical Trainer, Daniel Shull

Theses and Dissertations

One possible solution to common running related injuries is to transition runners from a rearfoot strike during initial contact to a midfoot strike. Natural rearfoot strike runners were studied to see if a modified elliptical trainer could be used to alter their running pattern to that of a midfoot strike runner. Their results were compared to subjects who ran on a non-modified elliptical trainer. After training on the modified elliptical trainer, subjects demonstrated a decrease in foot angle at initial contact when attempting to run with a midfoot strike. Training did not affect all kinetic metrics or stride frequency. However, …


Design Of A Fine-Needle Aspiration Biopsy Device For Thyroid Nodules, Troy Furst, Christa Spieth, Gunnar Lovhoiden, Michael Spieth Jan 2017

Design Of A Fine-Needle Aspiration Biopsy Device For Thyroid Nodules, Troy Furst, Christa Spieth, Gunnar Lovhoiden, Michael Spieth

Posters, Presentations, and Papers

While other devices currently exist to assist in FNA biopsies, none remove the repetitive whole wrist or arm movements needed to collect the sample.


A Wireless, Passive Sensor For Measuring Temperature At Orthopedic Implant Sites For Early Diagnosis Of Infections, Salil Sidharthan Karipott Jan 2017

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 Jan 2017

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 …


Final Design Report: Polymer Fatigue Characterization Test Method, Wyatt Ayling, Tyler Price, Brandon Stell, Michela Upson Dec 2016

Final Design Report: Polymer Fatigue Characterization Test Method, Wyatt Ayling, Tyler Price, Brandon Stell, Michela Upson

Mechanical Engineering

Polylogix is a team dedicated to the design, build, and testing of a fatigue machine to simulate cyclic loading on a biomedical polymer. This project is sponsored by Endologix, Inc. to provide test data characterizing mechanical material properties of various formulations of polymer used in abdominal aortic aneurysm surgeries. With this project goal, the machine must be able to test the polymer at body conditions; these include a testing temperature of 37°C and a cycling frequency ranging from 1 Hz to 10 Hz. This report proposes the following solution to this design challenge: an AC motor-driven mechanism utilizing a planetary …


Laboratory Development Of A Self-Powered Fontan For Treatment Of Congenital Heart Disease, Arka Das Dec 2016

Laboratory Development Of A Self-Powered Fontan For Treatment Of Congenital Heart Disease, Arka Das

Doctoral Dissertations and Master's Theses

Around 8% of all newborns with a Congenital Heart Defect (CHD) have only a single functioning ventricle. The Fontan operation has served as a palliation for this anomaly for decades, but the surgery entails multiple complications and survival rate is less than 50% by adulthood. A rapidly testable novel alternative is proposed by creating a bifurcating graft, or Injection Jet Shunt (IJS), used to “entrain” the pulmonary flow and thus provide assistance while reducing the caval pressure. A benchtop Mock Flow Loop (MFL) is configured to validate this hypothesis. The MFL is based on a Lumped-Parameter Model (LPM) of the …


Psychophysiological Analysis Of A Pedagogical Agent And Robotic Peer For Individuals With Autism Spectrum Disorders., Mohammad Nasser Saadatzi Dec 2016

Psychophysiological Analysis Of A Pedagogical Agent And Robotic Peer For Individuals With Autism Spectrum Disorders., Mohammad Nasser Saadatzi

Electronic Theses and Dissertations

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by ongoing problems in social interaction and communication, and engagement in repetitive behaviors. According to Centers for Disease Control and Prevention, an estimated 1 in 68 children in the United States has ASD. Mounting evidence shows that many of these individuals display an interest in social interaction with computers and robots and, in general, feel comfortable spending time in such environments. It is known that the subtlety and unpredictability of people’s social behavior are intimidating and confusing for many individuals with ASD. Computerized learning environments and robots, however, prepare a predictable, …


An Emg-Based Patient Monitoring System Using Zynq Soc Device, Farhad Fallahlalehzari Dec 2016

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 Dec 2016

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 Dec 2016

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 …


A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao Dec 2016

A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao

Graduate Theses and Dissertations

Foodborne diseases are a growing public health problem. In recent years, many rapid detection methods have been reported, but most of them are still in lab research and not practical for use in the field. In this study, a portable and automatic biosensing instrument was designed and constructed for separation and detection of target pathogens in food samples using nanobead-based magnetic separation and quantum dots (QDs)-labeled fluorescence measurement. The instrument consisted of a laptop with LabVIEW software, a data acquisition card (DAQ), a fluorescent detector, micro-pumps, stepper motors, and 3D printed tube holders. First, a sample in a syringe was …


Design Of A Flexible Control Platform And Miniature In Vivo Robots For Laparo-Endoscopic Single-Site Surgeries, Lou P. Cubrich Dec 2016

Design Of A Flexible Control Platform And Miniature In Vivo Robots For Laparo-Endoscopic Single-Site Surgeries, Lou P. Cubrich

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Minimally-invasive laparoscopic procedures have proven efficacy for a wide range of surgical procedures as well as benefits such as reducing scarring, infection, recovery time, and post-operative pain. While the procedures have many advantages, there are significant shortcomings such as limited instrument motion and reduced dexterity. In recent years, robotic surgical technology has overcome some of these limitations and has become an effective tool for many types of surgeries. These robotic platforms typically have an increased workspace, greater dexterity, improved ergonomics, and finer control than traditional laparoscopic methods. This thesis presents the designs of both a four degree-of-freedom (DOF) and 5-DOF …


A Prototype Bioreactor Incubation System Designed To Improve Cell Response Modeling In Microgravity, Greg Duke, Ryan Longchamps, Azita Amiri Oct 2016

A Prototype Bioreactor Incubation System Designed To Improve Cell Response Modeling In Microgravity, Greg Duke, Ryan Longchamps, Azita Amiri

Von Braun Symposium Student Posters

No abstract provided.


Surface Engineering Of Titanium Alloy To Stimulate The Bone Regeneration, Yubin Meng, Zhenduo Cui, Zhaoyang Li, Xue Li, Jin Zhao, Xubo Yuan, Xianjin Yang Oct 2016

Surface Engineering Of Titanium Alloy To Stimulate The Bone Regeneration, Yubin Meng, Zhenduo Cui, Zhaoyang Li, Xue Li, Jin Zhao, Xubo Yuan, Xianjin Yang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.


Evaluation Of An Actuated Wrist Orthosis For Use In Assistive Upper Extremity Rehabilitation, Devon Holley Oct 2016

Evaluation Of An Actuated Wrist Orthosis For Use In Assistive Upper Extremity Rehabilitation, Devon Holley

Master's Theses (2009 -)

Cerebral palsy (CP) is a neurological condition caused by damage to motor control centers of the brain. This leads to physical and cognitive deficiencies that can reduce an individual’s quality of life. Specifically, motor deficiencies of the upper extremity can make it difficult for an individual to complete everyday tasks, including eating, drinking, getting dressed, or combing their hair. Physical therapy, involving repetitive tasks, has been shown to be effective in training normal motion of the limb by invoking the neuroplasticity of the brain and its ability to adapt in order to facilitate motor learning. Creating a device for use …


A Fourier Description Of Covariance, And Separation Of Simultaneously Encoded Slices With In-Plane Acceleration In Fmri, Mary C. Kociuba Oct 2016

A Fourier Description Of Covariance, And Separation Of Simultaneously Encoded Slices With In-Plane Acceleration In Fmri, Mary C. Kociuba

Dissertations (1934 -)

Functional magnetic resonance imaging (fMRI) studies aim to identify localized neural regions associated with a cognitive task performed by the subject. An indirect measure of the brain activity is the blood oxygenation level dependent (BOLD) signal fluctuations observed within the complex-valued spatial frequencies measured over time. The standard practice in fMRI is to discard the phase information after image reconstruction, even with evidence of biological task-related change in the phase time-series. In the first aim of this dissertation, a complex-valued time-series covariance is derived as a linear combination of second order temporal Fourier frequency coefficients. As opposed to magnitude-only analysis, …


Materials And Techniques Used In Cranioplasty Fixation: A Review, Basel A. Khader, Mark R. Towler Sep 2016

Materials And Techniques Used In Cranioplasty Fixation: A Review, Basel A. Khader, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Cranioplasty is the surgical repair of a deficiency or deformity of the skull. The purpose of cranioplasty is to provide protection for the brain following cranial surgery, and to offer relief to psychological disadvantages while increasing social performance. There are several materials that had been used for cranioplasty, but an ideal product has yet to be developed, hence the ongoing research into biologic and non-biologic alternatives to the existing materials. This article critiques the products currently used for cranioplasty in order to facilitate the development of new materials, which can improve patient outcomes.


A 3-D Multiplex Paper-Microfluidic Platform, Mitchell Patrick Young Sep 2016

A 3-D Multiplex Paper-Microfluidic Platform, Mitchell Patrick Young

Master's Theses

3-D paper-based microfluidic devices (micoPADs) are small and portable devices made out of paper that offer a promising platform for diagnostic applications outside of a laboratory. These devices are easy to use, low cost, require no power source, and capable of detecting multiple targets simultaneously. The work in this thesis demonstrated the ability of a 3-D paper-microfluidic platform to simultaneously detect 5 targets. Rubber cord stock was used in conjunction with an acrylic housing unit to apply pressure along the edge of the channel. The indirect pressure application was successful in promoting vertical fluid flow between layers. Average channel development …


Continuous Isolation Of Monocytes Using A Magnetophoretic-Based Microfluidic Chip, Jeff Darabi, Chuan Guo Aug 2016

Continuous Isolation Of Monocytes Using A Magnetophoretic-Based Microfluidic Chip, Jeff Darabi, Chuan Guo

SIUE Faculty Research, Scholarship, and Creative Activity

Monocytes play an important role in the immune system and are responsible for phagocytizing and degrading foreign microorganisms in the body. The isolation of monocytes is important in various immunological applications such as in-vitro culture of dendritic cells. We present a magnetophoretic-based microfluidic chip for rapid isolation of highly purified, untouched monocytes from human blood by a negative selection method. This bioseparation platform integrates several unique features into a microfluidic device, including locally engineered magnetic field gradients and a continuous flow with a buffer switching scheme to improve the performance of the cell separation process. The results indicate high monocyte …


A Proposal For A Wirelessly Powered, Implantable Pressure Sensor And Neural Stimulator For The Control Of Urinary Incontinence, Robert N. Tucker, Christopher J. Quinkert, Pedro P. Irazoqui Aug 2016

A Proposal For A Wirelessly Powered, Implantable Pressure Sensor And Neural Stimulator For The Control Of Urinary Incontinence, Robert N. Tucker, Christopher J. Quinkert, Pedro P. Irazoqui

The Summer Undergraduate Research Fellowship (SURF) Symposium

47 to 53 percent of women over the age of 20 suffer from urinary incontinence, often caused by childbirth-related damage to the pelvic nerve. This uncertainty of when bladder voiding will occur causes social anxiety and can compromise quality of life. This study explores one method to restore the ability to sense the need to urinate and prevent unwanted voiding. We propose a device to measure pressure due to bladder content as the difference between pressure in the bladder and pressure in the abdominal cavity. Integrated circuits, biocompatible packaging, and wireless radiofrequency powering allow for a fully implantable device to …


Development Of Micro-/Nano-Architectures For Intracellular Sensing Platform, Ryan M. Preston, Dae Seung Wie, Chi Hwan Lee Aug 2016

Development Of Micro-/Nano-Architectures For Intracellular Sensing Platform, Ryan M. Preston, Dae Seung Wie, Chi Hwan Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Currently available nanotechnologies are capable of creating various nanostructures in controlled dimensions such as particles (0D), wires (1D), membranes (2D), and cubes (3D) by exploiting “top-down” or “bottom-up” methods. However, there exist limitations to systematically construct hierarchical nanostructures with geometric complexities. This study is focused on developing a novel nanofabrication strategy that can rationally produce a set of hierarchical nanostructures configured with precisely engineered facets, tip shapes, and tectonic motifs. We aim to identify a collection of optimal materials, array layouts, basic components, and nanofabrication techniques for the production of hierarchical nanostructures by exploiting device-grade semiconducting silicon materials. To accomplish …


Lipid Detection In Pig Arteries Using Intravascular Photoacoustic Imaging, Jieying Mai, Yingchun Cao, Ayeeshik Kole, Michael Sturek, Ji-Xin Cheng Aug 2016

Lipid Detection In Pig Arteries Using Intravascular Photoacoustic Imaging, Jieying Mai, Yingchun Cao, Ayeeshik Kole, Michael Sturek, Ji-Xin Cheng

The Summer Undergraduate Research Fellowship (SURF) Symposium

Heart disease is the leading cause of death in the United States and worldwide. Each year over 370,000 people died from coronary artery disease in America. As the primary form of coronary artery disease, atherosclerosis behaves as lipid-rich plaque development inside an artery wall. Vulnerable plaques are those prone to rupture, which may result in thrombus or even death. Typical hallmarks of a vulnerable plaque include thin fibrous cap, a large lipid-rich necrotic core and inflammatory infiltrate. The identification and accurate detection of these lipid depositions in the arterial wall is crucial in the diagnosis of atherosclerosis. However, none of …