Biomedical Engineering and Bioengineering Commons^™

Sapien3 Comb Stitch Improvement For Edwards Lifesciences, William Harley, Thomas Pluschkell, John Mctigue, Garrett Reed

Mechanical Engineering

The complete senior project report was submitted to the project advisor and sponsor. The results of this project are of a confidential nature and will not be published at this time.

Transcatheter Heart Valve Subassembly Device, Adam Aslam, Matthew Bezkrovny, Daniel Degree

Mechanical Engineering

No abstract provided.

The Influence Of Neuromusculoskeletal Model Calibration Method On Predicted Knee Contact Forces During Walking, Gil Serrancolí, Allison Kinney, Benjamin J. Fregly, Josep M. Font-Llagunes

Mechanical and Aerospace Engineering Faculty Publications

This study explored the influence of three model calibration methods on predicted knee contact and leg muscle forces during walking. Static optimization was used to calculate muscle activations for all three methods. Approach A used muscle-tendon model parameter values (i.e., optimal muscle fiber lengths and tendon slack lengths) taken directly from literature. Approach B used a simple algorithm to calibrate muscle-tendon model parameter values such that each muscle operated within the ascending region of its normalized force-length curve. Approach C used a novel two-level optimization procedure to calibrate muscle-tendon, moment arm, and neural control model parameter values while simultaneously predicting …

A Comprehensive Review Of The Food And Drug Administration, The 510(K) Application Process, And Fda Certification For A Diagnostic Device, Taylor Davis

Biomedical Engineering

The company G-Force CRC LLC is currently experiencing the dichotomy of the FDA's conflicting role right now as they begin to approach FDA approval. G-Force CRC LLC is a small medical device company headquartered in San Diego, CA. The owner of the company, Dr. Ian Purcell, is an Otoneurologist apart of Alvarado Hospital. His medical practice mainly deals with patients who have balance disorders and therefore the devices that he has developed over the last 6+ years are primarily used to assist in the diagnosis of those balance disorders. G-Force CRC LLC was officially created in the summer of 2013 …

Multiphysics Modeling To Enhance Understanding Of Microwave Heating Of Food In Domestic Ovens, Jiajia Chen

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Nonuniform heating is the biggest issue in the microwave heating of prepared meals. Multiphysics based models are promising tools to improve microwave heating uniformity by properly designing the food product. However, limited availability of accurate temperature-dependent material properties, inadequate model prediction accuracy, and high computational power and complexity in model development are three gaps that greatly limited the application of these models in the food industry.

To fill in the gaps, firstly, we developed a multitemperature calibration protocol to measure temperature-dependent dielectric properties (dielectric constant and loss factor). The temperature-dependent dielectric and thermal (thermal conductivity and specific heat capacity) properties …

Assured Bacterial Detection Towards Paper-Based Microfluidic Chip For Resource-Limited Areas, William Leineweber, Mallory Williams

Bioengineering Senior Theses

There is a significant and urgent need for affordable, fast, and accurate pathogen detection methods in resource-limited settings. Currently, accurate pathogen detection methods are dependent upon special equipment or reagents, specialized training to operate such equipment, electricity or cold storage, or sterile environments not feasible outside of the laboratory. Here we present a functionalized cellulose paper device towards an autonomous 3- dimensional microfluidics chip to detect bacterial pathogens. The microfluidic device utilizes a nucleic acid sandwich assay that detects the presence of bacterial RNA through complementary strand binding. An oligonucleotide “capture strand” immobilizes the targeted RNA sequence to the device, …

Micro Electrostatic Actuation Of A Silicon Diaphragm, Matthew W. Samples

Master's Theses

There are a number of applications, from hearing aids to microfluidic pumps, which utilize micro-scale actuating diaphragms. These MEMS (micro-electromechanical system) devices can be actuated by electrostatic forces, which utilize an induced electric field to pull two charged plates towards one another. Such devices were fabricated and electrostatic actuation of the diaphragms was performed to analyze its viability as a micro-speaker. The long-term performance of such products requires adequate diaphragm deflection to create audible pressure waves with relatively low maximum stresses to ensure a high cycle fatigue life. With these requirements, initial calculations and FEA (finite element analysis) were performed …

A Finite Element Analysis On The Viscoelasticity Of Postmenopausal Compact Bone Utilizing A Complex Collagen D-Spacing Model, Austin C. Cummings

Master's Theses

The nanoscale dimension known as D-spacing describes the staggering of collagen molecules, which are fundamental to the biphasic makeup of bone tissue. This dimension was long assumed to be constant, but recent studies have shown that the periodicity of collagen is variable. Given that the arrangement of collagen molecules is closely related to the degree of bone mineralization, recent studies have begun to look at D-spacing as a potential factor in the ongoing effort to battle postmenopausal osteoporosis. The theoretical models presented by previous studies have only opted to model a single collagen-hydroxyapatite period, so the creation of an intricate …

Characterization Of Two Vernier-Tuned Distributed Bragg Reflector (Vt-Dbr) Lasers Used In Swept Source Optical Coherence Tomography (Ss-Oct), Greg M. Bergdoll

Master's Theses

Insight Photonic Solutions Inc. has continued to develop their patented VT-DBR laser design; these wavelength tunable lasers promise marked image-quality and acquisition time improvements in SS-OCT applications.

To be well suited for SS-OCT, tunable lasers must be capable of producing a highly linear wavelength sweep across a tuning range well-matched to the medium being imaged; many different tunable lasers used in SS-OCT are compared to identify the optimal solution.

This work electrically and spectrally characterizes two completely new all-semiconductor VT-DBR designs to compare, as well. The Neptune VT-DBR, an O-band laser, operates around the 1310 nm range and is a …

Development And Validation Of A Tibiofemoral Joint Finite Element Model And Subsequent Gait Analysis Of Intact Acl And Acl Deficient Individuals, Nicholas Czapla

Master's Theses

Osteoarthritis (OA) is a degenerative condition of articular cartilage that affects more than 25 million people in the US. Joint injuries, like anterior cruciate ligament (ACL) tears, can lead to OA due to a change in articular cartilage loading. Gait analysis combined with knee joint finite element modeling (FEM) has been used to predict the articular cartilage loading. To predict the change of articular cartilage loading during gait due to various ACL injuries, a tibiofemoral FEM was developed from magnetic resonance images (MRIs) of a 33 year male, with no prior history of knee injuries. The FEM was validated for …

Design And Fabrication Techniques Of Devices For Embedded Power Active Contact Lens, Errol Heradio Leon

Master's Theses

This thesis designed and fabricated various devices that were interfaced to an IC for an active contact lens that notifies the user of an event by detection of an external wireless signal. The contact lens consisted of an embedded antenna providing communication with a 2.4GHz system, as well as inductive charging at an operating frequency of 13.56 MHz. The lens utilized a CBC005 5µAh thin film battery by Cymbet and a manufactured graphene super capacitor as a power source. The custom integrated circuit (IC) was designed using the On Semiconductor CMOS C5 0.6 µm process to manage …

Self-Contained Breathing Apparatus For Firefighter With A Permanent Stoma, Jason Delgadillo, Aaron Wheeler, Zachary Wishbow

Biomedical Engineering

The purpose of this project was to create a unique SCBA (self-contained breathing apparatus) for a firefighter named Chris Gauer. This prototype consists of a SCBA headgear connected to a polycarbonate-formed stoma mask with a medical-grade sanitary silicone hose.

Renal Artery Stent Fatigue Test, Braden Cooper, Munir Eltal, Jennifer Hawthorne, Ashley Schaefer

Mechanical Engineering

In today’s world of medical innovation, regulations and requirements set by organizations such as the Food and Drug Administration (FDA), the International Organization for Standardization (ISO), and ASTM International (American Society for Testing and Materials) can inhibit rapid innovation by demanding rigorous testing of new designs. For arterial stents, the standard is that each design must be tested to simulate 10 years of life in an environment congruent to an in vivo environment. Endologix in Irvine, California develops and manufactures minimally invasive treatments for aortic diseases, with a focus on stent grafts for the treatment of abdominal aortic aneurysms (AAA). …

Fibroblast-Derived Extracellular Matrix: An Alternative Cell Culture Substrate That Alters Lung Cancer Cell Line Phenotype., Michael Thomas Scherzer

Electronic Theses and Dissertations

Poor lung cancer survival can largely be contributed to the metastatic cells that invade and spread throughout the body. The tumor microenvironment (TME) is composed of multiple cell types, as well as non-cellular components. The TME plays a critical role in the development of metastatic cancers by providing migratory cues that change the growing tumor’s properties. The Extracellular Matrix (ECM), a main component of the TME, has been shown to change composition during tumor progression, allowing cancer cells to invade tissue and survive away from the primary cancer site. Although the ECM is well-known to influence the fate of tumor …

High Frequency Field Potentials Of The Cerebellar Cortex, Jonathan David Groth

Dissertations

The cerebellum plays a crucial role in motor coordination along with basal ganglia and the motor areas of the cerebral cortex. Both somatosensory and the cerebro-cerebral pathways bring in massive amounts of neural information to the cerebellum. The output of the cerebellar cortex projects to various motor cortices as well as down to the spinal cord to make its contributions to the motor function.

The origin and function of the field potential oscillations in the cerebellum, especially in the high frequencies, have not been explored sufficiently. The primary objective of this study was to investigate the spatio-temporal characteristics of high …

Piezoelectric Scaffolds For Osteochondral Defect Repair, Sita Mahalakshmi Damaraju

Dissertations

Osteoarthritis is one of the most prevalent causes of disability affecting nearly 27 million Americans. Osteoarthritis is caused when extensive damage occurs to the articular cartilage later spreading to the underlying subchondral bone, resulting in osteochondral defects. The current clinical therapies aim at regenerating the hyaline cartilage, but instead fibrocartilage forms at the osteochondral defect site, which is inferior in structure and function and fails to integrate with the surrounding tissue. A biomimetic scaffold, which can provide cues similar to the native extracellular matrix, may facilitate osteochondral defect repair. Articular cartilage and bone extracellular matrix have been shown to produce …

Differentiation Of Mouse Embryonic Stem Cells Into Insulin-Producing Cells: Optimization To Enhance The Overall Differentiation Efficiency, Xiaotang Ma

Theses

Embryonic stem cells have the potential to differentiate into multiple cell types including insulin-producing cells (IPCs), which is becoming one of the promising cell sources for treating type 1 diabetes mellitus. However, in order to achieve functional stem cell-derived cells, it is important to generate more mature IPCs and to keep long-term viability post differentiation process. In this study, we varied several factors including different embryonic body culture conditions, digested cells seeding density and various coatings required for differentiation to optimize a previously established protocol to enhance the overall differentiation efficiency. Moreover, a three-dimensional in vitro collagen tissue culture system …

Tendon Reflex Protocol For Exploring The Mechanisms Associated With Whole Body Vibration, Ikechukwu Okeke

Theses

Whole body vibration (WBV) machines have in recent years been widely used as rehabilitation equipment. Whole body vibration has been shown to have positive effects on muscle response. Cerebral palsy (CP) is a neurodevelopmental condition that includes a group of non-progressive, but often changing, motor impairment syndromes arising in the early stages of human development. The aim of this project was to design a protocol and related instruments to assess the tendon reflex in response to WBV. Both a press pedal used for measuring the force exerted by the foot and a hammer used for measuring the stimulating force were …

Behavior Of Deformed Dermal Fibroblasts Seeded On A Silicon Membrane Under High Levels Of Strain, Laura Osorno

Theses

The main objective of this thesis is to understand, from a molecular perspective, the morphological and functional abnormalities of human dermal fibroblasts as a response to deformation produced by a normal force that can lead to the potential formation of stretch marks in pregnant women, adolescents, and people with Cushing's syndrome. The main function of dermal fibroblasts is to produce the essential fibrous components of the extracellular matrix (ECM) of the skin.

In order to study the mechanism of stretch mark formation, neonatal human dermal fibroblasts were seeded on a silicon membrane for controlled deformation. Upon reaching a confluence of …

Significant Degradability Enhancement In Multilayer Coating Of Polycaprolactone-Bioactive Glass/Gelatin-Bioactive Glass On Magnesium Scaffold For Tissue Engineering Applications, Mostafa Yazdimamaghani, Mehdi Razavi, Daryoosh Vashaee, Venkata Raveendra Pothineni, Jayakumar Rajadas, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Magnesium (Mg) is a promising candidate to be used in medical products especially as bone tissue engineering scaffolds. The main challenge for using Mg in biomedical applications is its high degradation rate in the body. For this reason, in this study, a multilayer polymeric layer composed of polycaprolactone (PCL) and gelatin (Gel) reinforced with bioactive glass (BaG) particles has been applied on the surface of Mg scaffolds. The materials characteristics of uncoated Mg scaffold, Mg scaffold coated only with PCL-BaG and Mg scaffold coated with PCL-BaG and Gel-BaG have been analyzed and compared in detail. Scanning electron microscope (SEM) equipped …