Biomedical Engineering and Bioengineering Commons^™

Meshr: A Modular, Economical Skin Graft Hand Roller, Maggie Alt, Josée Fournier, Madeline Krenek, Will Paton

Bioengineering Senior Theses

In South Africa and around the world, the rates of severe burns are a significant health issue. Skin grafts are used to improve the function and appearance of the burned area and reduce the amount of time a patient is in the hospital. To minimize the amount of skin needed and maximize the coverage of the graft, the harvested sample is meshed in a lattice pattern so it can expand and graft a much larger surface area. Unfortunately, the current methods and devices used in both high and low-income countries have been optimized for hospitals with larger budgets and more …

Assessing The Photoprotective Effects Of Fluorescent Sphingomyelin Against Uvb Induced Dna Damage In Human Keratinocytes, Rebecca Marie Kandell

Master's Theses

Non Melanoma Skin Cancer (NMSC) affects 3.3 million Americans each year and results from Ultra Violet Radiation (UVR) damage to DNA in the form of pyrimidine dimers and photoproducts [1]–[5]. Cells directly detect the damage and initiate apoptosis, cell cycle arrest, or DNA repair by modulating p53 and p21 levels [6]–[9]. Current methods of photoprotection include sunscreen, but controversy over safety of some active ingredients necessitates research into more natural alternatives [10]–[12]. In particular, 24 hour incubation with bovine milk sphingomyelin (BSM) has demonstrated photoprotective potential by reducing p21 and p53 levels in keratinocytes (KRTs) after UV radiation [13], [14]. …

Extended-Use Ecg Monitor, Daniel Aaron Soski

Master's Theses

In this thesis, a prototype ECG monitor was developed that is integrated into an elastic shirt and takes a 3-lead ECG for over 5 days. The high-quality measurements can be used to identify markers indicative of various detrimental heart conditions. Measurements recorded by the device are encrypted and stored onto a micro-SD card. Current Holter monitors are expensive and have functional lives less than 48 hours; however, extended duration monitoring has been proven more useful in diagnosis. The device designed demonstrates that ECG measurements can be taken over longer durations without sacrificing quality, comfort, or device cost.

Preparation Of Supramolecular Amphiphilic Cyclodextrin Bilayer Vesicles For Pharmaceutical Applications, Kate E. Frischkorn

Master's Theses

Recent pharmaceutical developments have investigated using supramolecular nanoparticles in order to increase the bioavailability and solubility of drugs delivered in various methods. Modification of the carbohydrate cyclodextrin increases the ability to encapsulate hydrophobic pharmaceutical molecules by forming a carrier with a hydrophobic core and hydrophilic exterior. Guest molecules are commonly added to these inclusion complexes in order to add stability and further increase targeting abilities of the carriers. One such guest molecule is adamantine combined with a poly(ethylene glycol) chain. Vesicles are formed by hydrating a thin film of amphiphilic cyclodextrin and guest molecules in buffer solution that mimics physiological …

Neuro-Silicon Interface Of A Hirudo Medicinalis Retzius Cell Integrated With Field Effect Transistor, Kurt Christian Sjoberg

Master's Theses

The focus of this thesis was to measure the intracellular voltage of a living neural cell using a silicon transistor. The coupling of neurological tissues with silicon devices is of interest to the fields of neurology, neuroscience, electrophysiology and cellular biology. In previous work by Peter Fromherz, single neurons were successfully coupled to transistors [1]. This thesis aims to show proof of concept of the fabrication of a simple neuro-silicon interface using wafer processing methods currently available at Cal Poly. The types of transistors and cells used, the methods for dissecting and preparing the cells, the electrophysiology methods for validating …

Characterization Of Arterial Flow For Junctional Bleeding Control, Nick Bosio

Master's Theses

This study investigated reducing volumetric flowrate under steady flow conditions by varying lengths of compression with constant cross-sectional area and varying cross-sectional area reduction with constant length in order to better understand how to control junctional hemorrhaging. The hypotheses of this study were that length reduction will have little effect on volumetric flowrate and that cross-sectional area reduction would need to be approximately 80 percent in order to obtain bleeding control. The study found that length reduction has little effect on changing the flowrate. However, in order to obtain at least 80 percent reduction in flow, the area needs to …

Validation Of A 1d Algorithm That Measures Pulse Wave Velocity To Estimate Compliance In Blood Vessels, James Leung

Master's Theses

The purpose of this research is to determine if it is possible to validate the new 1D method for measuring pulse wave velocity in the aorta in vivo and estimate compliance. Arterial pressure and blood flow characterize the traveling of blood from the heart to the arterial system and have played a significant role in the evaluation of cardiovascular diseases. Blood vessel distensibility can give some information on the evolution of cardiovascular disease. A patient’s aorta cannot be explanted to measure compliance; therefore we are using a flow phantom model to validate the 1D pulse wave velocity technique to estimate …

Comparative Analysis Of Physiological Measurements And Environmental Metrics On Predicting Heat Stress Related Events, Mckenzie Lee Barlow

Master's Theses

Exposure to high heat and humidity can lead to serious health risks, including heat exhaustion and heat stroke. Wet Bulb Globe Temperature (WBGT) and heat index have historically been used to predict heat stress events, but individualized factors are not included in the measurement. It has been shown that there is a relationship between cardiovascular measurements and heat stress, which could be used to measure heat stress risk on an individual level. Research has been done to find relationships between cardiovascular metrics in a workplace environment, however the study did not include the use of a controlled environment as a …

Posterior Cervical Spine Crisscross Fixation: Biomechanical Evaluation, Joseph F. Cusick, Frank A. Pintar, Joseph S. Cheng, Jason I. Lifshutz, Narayan Yoganandan

Biomedical Engineering Faculty Research and Publications

Background

Biomechanical/anatomic limitations may limit the successful implantation, maintenance, and risk acceptance of posterior cervical plate/rod fixation for one stage decompression-fusion. A method of posterior fixation (crisscross) that resolves biomechanical deficiencies of previous facet wiring techniques and not reliant upon screw implantation has been devised. The biomechanical performance of the new method of facet fixation was compared to the traditional lateral mass plate/screw fixation method.

Methods

Thirteen human cadaver spine segments (C2-T1) were tested under flexion-compression loading and four were evaluated additionally under pure-moment load. Preparations were evaluated in a sequence of surgical alterations with intact, laminectomy, lateral mass plate/screw …

Diffusion Tensor Imaging In A Large Longitudinal Series Of Patients With Cervical Spondylotic Myelopathy Correlated With Long-Term Functional Outcome, Avinash Rao, Hesham Soliman, Mayank Kaushal, Olesya Motovylyak, Aditya Vedantam, Matthew D. Budde, Brian D. Schmit, Marjorie C. Wang, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

BACKGROUND

Fractional anisotropy (FA) of the high cervical cord correlates with upper limb function in acute cervical cord injury. We investigated the correlation between preoperative FA at the level of maximal compression and functional recovery in a group of patients after decompressive surgery for cervical spondylotic myelopathy (CSM).

OBJECTIVE

To determine the usefulness of FA as a biomarker for severity of CSM and as a prognostic biomarker for improvement after surgery.

METHODS

Patients received diffusion tensor imaging (DTI) scans preoperatively. FA values of the whole cord cross-section at the level of maximal compression and upper cervical cord (C1-2) were calculated. …

Analysis Of The Low-Cycle Fatigue Behavior Of Silicone Rubber For Biomedical Balloons, Chase Cooper

Materials Engineering

The development of a medical drug delivery device that allows for the deployment drugs into the adventitial tissue of blood vessels requires the inflation of a silicone elastomer. The inflated silicone must be able to consistently endure multiple loading cycles without failing so that the device can operate reliably. There are multiple methods of processing the silicone for the device and the goal of this study is to examine the effect of the various processing methods on the characteristics of the silicone. The Dynamic Mechanical Analysis Machine (DMA) is used to model the conditions of the device’s application by performing …

Milkguard: Low-Cost, Polymer-Based Sensor For The Detection Of Escherichia Coli In Donated Human Breast Milk, Maggie May, Nicholas Kikuchi, Matthew Zweber

Bioengineering Senior Theses

Breast milk, the gold standard for infant nutrition, could prevent up to 13% of child deaths worldwide. However, many mothers are unable to breastfeed due to health conditions and other factors. Because of this, a network of more than 500+ human milk banks, which collect and distribute donated breast milk to infants, have emerged worldwide. However, operational costs to ensure the safety of this milk remain time-intensive and costly.

There are no existing diagnostics for rapid and on-site detection of bacterial contaminants in donated milk. Currently, many milk banks send samples to outside laboratories for bacterial culturing tests, which take …

Bioactive Polydimethylsiloxane Surface For Optimal Human Mesenchymal Stem Cell Sheet Culture, Zichen Qian, David Ross, Wenkai Jia, Qi Xing, Feng Zhao

Michigan Tech Publications, Part 1

Human mesenchymal stem cell (hMSC) sheets hold great potential in engineering three-dimensional (3D) completely biological tissues for diverse applications. Conventional cell sheet culturing methods employing thermoresponsive surfaces are cost ineffective, and rely heavily on available facilities. In this study, a cost-effective method of layer-by-layer grafting was utilized for covalently binding a homogenous collagen I layer on a commonly used polydimethylsiloxane (PDMS) substrate surface in order to improve its cell adhesion as well as the uniformity of the resulting hMSC cell sheet. Results showed that a homogenous collagen I layer was obtained via this grafting method, which improved hMSC adhesion and …

Intercellular Sodium Nanodomain Signaling Regulates Repolarization In Cardiac Tissue, Madison Nowak, Seth Weinberg Ph.D.

Biology and Medicine Through Mathematics Conference

No abstract provided.

Chemotherapeutic Drug Cytotoxicity Measurement With A 3d Biomimetic Microfluidic Device And Computational Fluid Dynamics Model, Maryam Moarefian, Caroline Jones, Luke Achenie, Danesh Tafti

Biology and Medicine Through Mathematics Conference

No abstract provided.

Investigating Smoke Exposure And Chronic Obstructive Pulmonary Disease (Copd) With A Calibrated Agent Based Model (Abm) Of In Vitro Fibroblast Wound Healing., J Alex Ratti, Angela Reynolds, Rebecca L. Heise

Biology and Medicine Through Mathematics Conference

No abstract provided.

Quantifying Effects Of Neutrophil Memory On Migration Patterns Using Microfluidic Platforms And Ode Modeling Of The Mechanistic Molecular Pathways, Brittany P. Boribong, Mark J. Lenzi, Mirjam Sarah Kadelka, Stanca Ciupe, Liwu Li, Caroline N. Jonea

Biology and Medicine Through Mathematics Conference

No abstract provided.

Prediction Of Forelimb Muscle Activities And Movement Phases Using Corticospinal Signals In The Rat, Sinan Gok

Dissertations

The targeted population for this project is primarily patients with high level spinal cord injury (SCI) and individuals with motor neuron diseases (MND). In both SCI and MND cases motor control is interrupted due to lack of communication between the brain and the musculature, although both sides are otherwise functional. The approach in this project is to use neural engineering techniques to restore the motor function that was lost because of an injury or disease.

Brain-computer interfaces (BCIs) attempt to extract the volitional signals from the cortex when the brain's normal outputs to the musculoskeletal system are impaired. However, BCIs …

Submandibular Mechanical Stimulation Of Upper Airway Muscles To Treat Obstructive Sleep Apnea, Ferhat Erdogan

Dissertations

The extrinsic tongue muscles are activated in coordination with pharyngeal muscles to keep a patent airway during respiration in wakefulness and sleep. The activity of genioglossus, the primary tongue-protruding muscle playing an important role in this coordination, is known to be modulated by several reflex pathways mediated through the mechanoreceptors of the upper airways. The main objective is to investigate the effectiveness of activating these reflex pathways with mechanical stimulations, for the long-term goal of improving the upper airway patency during disordered breathing in sleep. The genioglossus response is examined during mandibular and sub-mandibular mechanical stimulations in healthy subjects during …

Fluorescent Probes And Functionalized Nanoparticles For Bioimaging: Synthesis, Photophysical Properties And Applications, Xinglei Liu

Dissertations

The development of new organic molecular probes with excellent photophysical properties and high fluorescence quantum yields is of considerable interest to many research areas including one- and two-photon fluorescence microscopy, fluorescence-based sensing methodologies, and cancer therapy. Series of organic linear-/non-linear optical molecules including squaraine derivatives, and fluorene derivatives as well as other bioconjugates are designed and synthesized during the doctoral study for the aim of ion detection (Chapter 5), photo dynamic therapy, and deep-tissue imaging (Chapter 4). These optical probes are capable of absorbing light in the near infrared (NIR) window and thus have deeper penetration and cause less photodamage …