Aging Effects On Airflow Dynamics And Lung Function In Human Bronchioles, Jongwon Kim, Rebecca L. Heise, Angela M. Reynolds, Ramana M. Pidaparti

Biomedical Engineering Publications

Background and objective

The mortality rate for patients requiring mechanical ventilation is about 35% and this rate increases to about 53% for the elderly. In general, with increasing age, the dynamic lung function and respiratory mechanics are compromised, and several experiments are being conducted to estimate these changes and understand the underlying mechanisms to better treat elderly patients.

Materials and methods

Human tracheobronchial (G1 ~ G9), bronchioles (G10 ~ G22) and alveolar sacs (G23) geometric models were developed based on reported anatomical dimensions for a 50 and an 80-year-old subject. The aged model was developed by altering the geometry and …

A Modified Fasp Protocol For High-Throughput Preparation Of Protein Samples For Mass Spectrometry., Jeremy Potriquet, Marut Laohaviroj, Jeffrey M Bethony, Jason Mulvenna

Microbiology, Immunology, and Tropical Medicine Faculty Publications

o facilitate high-throughput proteomic analyses we have developed a modified FASP protocol which improves the rate at which protein samples can be processed prior to mass spectrometry. Adapting the original FASP protocol to a 96-well format necessitates extended spin times for buffer exchange due to the low centrifugation speeds tolerated by these devices. However, by using 96-well plates with a more robust polyethersulfone molecular weight cutoff membrane, instead of the cellulose membranes typically used in these devices, we could use isopropanol as a wetting agent, decreasing spin times required for buffer exchange from an hour to 30 minutes. In a …

Human Liver Sinusoid On A Chip For Hepatitis B Virus Replication Study, Young Bok (Abraham) Kang, Siddhartha Rawat, Nicholas Duchemin, Michael Bouchard, Moses Noh

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

We have developed a miniature human liver (liver-sinusoid-on-a-chip) model using a dual microchannel separated by a porous membrane. Primary human hepatocytes and immortalized bovine aortic endothelial cells were co-cultured on opposite sides of a microporous membrane in a dual microchannel with continuous perfusion. Primary human hepatocytes in this system retained their polygonal morphology for up to 26 days, while hepatocytes cultured in the absence of bovine aortic endothelial cells lost their morphology within a week. In order to demonstrate the utility of our human-liver-sinusoid-on-a-chip, human hepatocytes in this system were directly infected by Hepatitis B Virus (HBV). Expression of the …

Predictive Behavior Of A Computational Foot/Ankle Model Through Artificial Neural Networks, Ruchi D. Chande, Rosalyn Hobson Hargraves, Norma Ortiz-Robinson, Jennifer S. Wayne

Biomedical Engineering Publications

Computational models are useful tools to study the biomechanics of human joints. Their predictive performance is heavily dependent on bony anatomy and soft tissue properties. Imaging data provides anatomical requirements while approximate tissue properties are implemented from literature data, when available. We sought to improve the predictive capability of a computational foot/ankle model by optimizing its ligament stiffness inputs using feedforward and radial basis function neural networks. While the former demonstrated better performance than the latter per mean square error, both networks provided reasonable stiffness predictions for implementation into the computational model.

Computer-Aided Cancer Diagnosis And Grading Via Sparse Directional Image Representations, Hadi Rezaeilouyeh

Electronic Theses and Dissertations

Prostate cancer and breast cancer are the second cause of death among cancers in males and females, respectively. If not diagnosed, prostate and breast cancers can spread and metastasize to other organs and bones and make it impossible for treatment. Hence, early diagnosis of cancer is vital for patient survival. Histopathological evaluation of the tissue is used for cancer diagnosis. The tissue is taken during biopsies and stained using hematoxylin and eosin (H&E) stain. Then a pathologist looks for abnormal changes in the tissue to diagnose and grade the cancer. This process can be time-consuming and subjective. A reliable and …

Mechanical Effects Of Surgical Adhesives On Ascending Thoracic Aortic Aneurysm Replacement, Dong Qiu

Electronic Theses and Dissertations

Ascending thoracic aortic aneurysm (aTAA) is a potentially lethal disease which grows gradually over time and may lead to aortic dissection and rupture. Currently, aTAA surgical repair using Dacron graft is a well-established treatment. In addition, surgical adhesives are frequently used in the surgeries to seal the anastomotic site. This study aims to investigate mechanical effects of four commonly used surgical adhesives, namely BioGlue, CoSeal, Crosseal, and Tisseel, on the suture site using in-vitro digital image correlation (DIC) method and finite element (FE) simulations in an ovine model. In this study, first, mechanical properties of ovine ascending aorta were obtained …

Low Cost, Adhesion Strength Based Cell Sorter, Emily Burtch, Franck Kamga-Gninzeko, Devin Mair, Sarah Saunders

Capstone Design Expo Posters

In many in vitro experiments, primary cells are harvested from an animal species to undergo experimental manipulation and subsequent analysis. Cell sorters are a luxury to have after cell harvesting to ensure pure populations of cells. Recently, it was discovered that different cell types adhere to cell culture dishes at different strengths. This observation was utilized in the invention of a cell sorting system that sorts cells based on this adhesion strength difference. The resulting system is marketable at under $2000, compared to $50000 plus for current commercially available systems, and is the first commercially-oriented cell adhesion strength based cell …

Antibody-Nanoparticle Conjugates To Enhance The Sensitivity Of Elisa-Based Detection Methods., Margaret M Billingsley, Rachel S. Riley, Emily S Day

Henry M. Rowan College of Engineering Departmental Research

Accurate antigen detection is imperative for clinicians to diagnose disease, assess treatment success, and predict patient prognosis. The most common technique used for the detection of disease-associated biomarkers is the enzyme linked immunosorbent assay (ELISA). In an ELISA, primary antibodies are incubated with biological samples containing the biomarker of interest. Then, detectible secondary antibodies conjugated with horseradish peroxidase (HRP) bind the primary antibodies. Upon addition of a color-changing substrate, the samples provide a colorimetric signal that directly correlates to the targeted biomarker concentration. While ELISAs are effective for analyzing samples with high biomarker content, they lack the sensitivity required to …

P1: Using Modified Dean Flow Designs To Increase Mixing Performance, Joshua Clark

Undergraduate Research Posters 2017

We are using numerical solutions for the Navier-Stokes equations and the concentration - diffusion equation to model fluid flow and reactant distribution in serpentine type channels for micromixers/microreactors development. These mixers exploit centripetal forces on the fluid to induce cross-sectional fluid mixing, aka Dean flows. Various modifications are used to increase the mixing character of these crosssectional flows. We found that the performance of these mixers exceeds that of unmodified channels and we currently assess their performance relative to other state of the art methodologies used to induce mixing on the microscale.

P2: Implementation Of Groove Based Designs For Engineering Fluid Flow In Micromixers, Tahir Butt

Undergraduate Research Posters 2017

Mixing on microscale is important for the development of miniaturized chemical reactors that use small quantities of reactants and allow better control over the reaction conditions and products. Nevertheless, achieving rapid mixing in this type of micro-reactors is challenging due to the lack of turbulence and slow diffusion on the microscale. In this work we implement micromixers designs based on surface groove/ridge patterns targeted at inducing cross-sectional flows that both extend the interface between the different reactants, as well as induce chaotic advection. We discuss the fabrication of these structures using soft-lithography in PDMS employing a mold and their optical …

Going Green: Experimental Adaptation Of Scenedesmus Dimorphus To Marine Conditions, Mohammed Khalil

Undergraduate Research Posters 2017

Algae has gained some interest as the need for alternative fuels becomes more pressing. Reliance on fossil fuels is causing our environment and economy harm, and is not sustainable moving forward. Lipid rich algae strains can be used in the production of biofuels, and provide an alternative fuel source. One challenge facing the prospect of algae as a fuel source is that lipid rich algae grows exclusively in freshwater. Considering the scarcity and cost to use freshwater for algae growth, interest has grown in the possibility of adapting lipid rich, freshwater algae to a seawater environment. Seawater can have up …

Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny

Undergraduate Research Posters 2017

Establishing the role that mechanics play in nerve cell (e.g. neurons) function requires experimental testing. Microfluidic based experiments are commonly used to study neuron growth and function, and studies have found mechanics to play an important role in neuron health. External loads can be applied to a microfluidic device using a motor, which presumably influences the mechanical environment of the cells. While a motor can easily apply known displacements, a “load cell” is necessary to measure corresponding forces. In an existing prototype microfluidic loading device, a load cell was integrated and verified. The manufacturer's calibration of the load cell was …

Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin

Browse all Theses and Dissertations

We know that animals are tuned to survive different environmental conditions or else life would not exist. Unfortunately, this is often forgotten or ignored when designing experiments. As Marsh Tenney articulated, "The physiologist keeps the whole always in mind. He accepts the tactical necessity of reductionism to understand parts, but, once done, for him it is only the beginning, never the end” (from Remmers, 2005). In an era when it is all too common to take environmental complexity out of the organism to understand physiology, my work puts some of that complexity back in the study of organisms. I take …

Resting State Functional Network Disruptions In A Kainic Acid Model Of Temporal Lobe Epilepsy., Ravnoor Singh Gill, Seyed M Mirsattari, L Stan Leung

Physiology and Pharmacology Publications

We studied the graph topological properties of brain networks derived from resting-state functional magnetic resonance imaging in a kainic acid induced model of temporal lobe epilepsy (TLE) in rats. Functional connectivity was determined by temporal correlation of the resting-state Blood Oxygen Level Dependent (BOLD) signals between two brain regions during 1.5% and 2% isoflurane, and analyzed as networks in epileptic and control rats. Graph theoretical analysis revealed a significant increase in functional connectivity between brain areas in epileptic than control rats, and the connected brain areas could be categorized as a limbic network and a default mode network (DMN). The …

Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi

ETD Archive

Due to the rise of obesity, diabetes and cardiovascular disease, research in human performance and physical activity has received increased attention. Rowing machines are used for performance improvements through concentric exercises, however a combination of concentric and eccentric actions is known to improve the effectiveness of training. In this work, a conventional rowing machine was modified to include an electric motor and a robust impedance control system, enabling programmable impedance with concentric and eccentric capabilities. Eccentric exercises are known to contribute significantly to the efficacy of training and to diminish the detrimental effects of humans operating in microgravity for long …

Cathepsin K Targeting Matrix Regenerative Nanoparticles For Small Abdominal Aortic Aneurysm Repair, Jonathan M. Fox

ETD Archive

Abdominal aortic aneurysms (AAAs) are characterized by the loss of elasticity in the aorta wall leading to a chronic increase in diameter and resulting in rupture. This is due to the lack of regeneration of elastic fibers and chronic proteolytic breakdown of elastic fibers within the aorta mediated by matrix metalloproteinases (MMPs), specifically MMP-2 and -9. Previous studies in our lab have shown cationic amphiphile-surface functionalized poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with doxycycline (DOX) to inhibit MMP activity and stimulate elastic matrix synthesis, effects we attributed to both low doses (< 10 mg/ml) of DOX released and independent effects of cationic amphiphile pendant groups on the NP surface. This promises application of these NPs to arrest or regress AAA growth since high oral DOX dosing inhibits new elastic matrix formation in the AAA wall and has undesirable side effects. In this study, we investigated feasibility of antibody-based active targeting of intravenously infused NPs to the AAA wall. Cathepsin K, a cysteine protease, is a biomarker for AAA and overexpressed in abdominal aortic aneurysm tissue making it an ideal target moiety. We have shown using a covalent conjugation method of modifying the surface of the NPs with a cathepsin K antibody resulted in a more robust antibody attachment which did not affect the DOX release profile. Cathepsin K expression was confirmed to be localized on the cell surface and utilizing cathepsin K Ab-conjugated NPs, we demonstrated an increased NP localization to the cathepsin K overexpressing cells in vitro and ex vivo. Importantly, the DOX-loaded NPs demonstrated pro-elastogenic and anti-proteolytic effects in aneurysmal smooth muscle cells supporting their use as regenerative therapies to arrest and regress AAA growth. Preliminary data has been collected indicating cathepsin K Ab-conjugated NP targeting to AAAs in elastase-injured rat models. The study outcomes support the feasibility of using cathepsin K Ab-conjugated NPs as a targeted therapy for elastic matrix regeneration in AAA tissue and will serve as a basis for already initiated follow up studies to assess NP biodistribution, in situ retention in the AAA wall, and safety as a function of time.

A System To Monitor Segmental Intracellular, Interstitial, And Intravascular Volume And Circulatory Changes During Acute Hemodialysis, Leslie Montgomery, Richard Montgomery, Wayne Gerth, Marty Loughry, Susie Q. Lew, Manuel T. Velasquez

Medicine Faculty Publications

This paper describes a new combined impedance plethysmographic (IPG) and electrical bioimpedance spectroscopic (BIS) instrument and software that allows noninvasive real-time measurement of segmental blood flow and changes in intracellular, interstitial, and intravascular volumes during various fluid management procedures. The impedance device can be operated either as a fixed frequency IPG for the quantification of segmental blood flow and hemodynamics or as a multi-frequency BIS for the recording of intracellular and extracellular resistances at 40 discrete input frequencies. The extracellular volume is then deconvoluted to obtain its intra-vascular and interstitial component volumes as functions of elapsed time. The purpose of …

Expanding The Applications Of Poly(Dimethylsiloxane) In Biomicrofluidics, Sawyer D. Stone

Doctoral Dissertations

This work aims to create novel applications for poly(dimethylsiloxane) (PDMS) in the field of biomicrofluidics through oxidative stress detection, doping of the polymer for intentional leaching into microdevices, and the development of low-cost implements for fabricating PDMS microfluidic devices. PDMS has become the polymer of choice for research in microfluidics due to its optical clarity, ease of fabrication, flexibility in design, good mechanical properties, and the ability to chemically modify the surface.

Biomicrofluidics enables the rapid throughput and analysis of small biological samples requiring less time investment and reagent use than traditional macroscale laboratory techniques. Polymer devices are inexpensive, easily …

Biomechanics Of Concussion: The Importance Of Neck Tension, Ron Jadischke

Wayne State University Dissertations

Linear and angular velocity and acceleration of the head are typically correlated to concussion. Despite improvements in helmet performance to reduce accelerations, a corresponding reduction in the incidence of concussion has not occurred (National Football League [NFL] 1996 – present).

There is compelling research that forces on and deformation to the brain stem are related to concussion. The brain stem is the center of control for respiration, blood pressure and heart rate and is the root of most cranial nerves. Injury to the brain stem is consistent with most symptoms of concussion reported in the National Football League and the …

Anisotropy Evolution Due To Surface Treatment On 3d-Printed Fused Deposition Modeling (Fdm) Of Acrylonitrile Butadiene Styrene (Abs), Blake E. Lozinski

Honors Undergraduate Theses

Purpose: This paper will present insight to the methodology and results of the experimental characterization of Acrylonitrile Butadiene Styrene (ABS) using Fused Deposition Modeling (FDM). The work in this research explored the effects of print orientation, surface treatment, and ultraviolet (UV) light degradation with the utilization of Digital Image Correlation (DIC) on ABS tensile specimens.

Design/methodology: ABS specimens were printed at three build orientations (flat (0 degrees), 45 degrees, and up-right (90 degrees)). Each of these specimens were treated with three different surface treatments including a control (acrylic paint, Cyanoacrylate, and Diglycidyl Bisphenol A) followed by exposure to UV light …

Brain Connectivity After Concussion, Armin Iraji

Wayne State University Dissertations

Mild traumatic brain injury (mTBI) accounts for over one million emergency visits in the United States each year. While most mTBI patients have normal findings in clinical neuroimaging, alterations in brain structure and functional connectivity have frequently been reported. In this study, we investigated the large-scale brain structural and functional connectivity using diffusion MRI and resting-state fMRI data. Data from 40 mTBI patients was acquired at the acute stage (within 24 hrs after injury). 35 patients returned for data acquisition at a follow-up (4-6 weeks after injury). Data was also collected from a cohort of 58 healthy subjects, 36 of …

Development Of A Finite Element Pelvis And Lower Extremity Model With Growth Plates For Pediatric Pedestrian Protection, Ming Shen

Wayne State University Dissertations

Finite element (FE) model is a useful tool frequently used for investigating the injury mechanisms and designing protection countermeasures. At present, no 10 years old (YO) pedestrian FE model has been developed from appropriate anthropometries and validated against limitedly available impact response data. A 10 YO child FE pelvis and lower extremities (PLEX) model was established to fill the gap of lacking such models in this age group. The baseline model was validated against available pediatric postmortem human subjects (PMHS) test data and additional scaled adult data, then the PLEX model was integrated to build a whole-body FE model representing …

Impact Of A Localized Lean Six Sigma Implementation On Overall Patient Safety And Process Efficiency, Luvianca Gil, Pilar Pazos, Mamadou Seck, Rolando Delaguila

Engineering Management & Systems Engineering Faculty Publications

Continuous quality improvement tools have caught the attention of the Health Care Industry as a solution to process efficiency, patient safety and cost reduction. This research explores the impact of a Lean Six Sigma (LSS) process improvement initiative in overall process efficiency and patient safety in two Labor and Delivery (L+D) units of two large hospital providers. This study focuses on the application of modeling and simulation methodology to investigate the influence of a localized process improvement intervention on the overall L+D unit output, by considering patient flow, system capacity and unit performance. The simulation models capacity profiles and patient …

Sugar Versus Lipid For Sustainable Biofuels, Yaşar Demirel

Yaşar Demirel Publications

Introduction

First‐generation biofuels, namely, ethanol and biodiesel, have led to far reaching impact on the peoples’ life world‐wide.[1] However, they inter-fere with the food supply chain and may not be sustainable although some of the biomass are converted to biofuels after those biomasses have met the human needs. Still, the first‐generation–based biofuels have proved that sugar and lipid platforms can be an answer to energy security and global warming concerns without the need for new infrastructure for feedstock delivery as well as for biomass‐to‐biofuel conversion tech-nologies. At the same time, we are discovering and assessing the long‐term environmental im-plications on …

Development Of A Nonlinear Model For The Prediction Of Response Times Of Glucose Affinity Sensors Using Concanavalin A And Dextran And The Development Of A Differential Osmotic Glucose Affinity Sensor, Louis G. Reis

Doctoral Dissertations

With the increasing prevalence of diabetes in the United States and worldwide, blood glucose monitoring must be accurate and reliable. Current enzymatic sensors have numerous disadvantages that make them unreliable and unfavorable among patients. Recent research in glucose affinity sensors correct some of the problems that enzymatic sensors experience. Dextran and concanavalin A are two of the more common components used in glucose affinity sensors. When these sensors were first explored, a model was derived to predict the response time of a glucose affinity sensor using concanavalin A and dextran. However, the model assumed the system was linear and fell …

Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Probabilistic methods are applied to the study of fatigue wear of sliding surfaces. A variance of time to failure (to occurrence of maximum allowable wear depth) is evaluated as a function of a mean wear rate of normal wear and a size of wear particles. A method of estimating probability of failure-free work during a certain time interval (reliability) is presented. An effect of the bedding-in phase of wear on the reliability is taken into account. Experimental data for Ultra High Molecular Weight Polyethylene (UHMWPE) cups of artificial hip implants is used to make numerical calculations.

Lighted Ear Curette, Kelsey Ashmore, Kaitlin Klotzle, Crysta Yamamoto, Katrina Elfrink, Cynthia Stoller

Williams Honors College, Honors Research Projects

The ear canal is a sensitive and small part of the human body that is prone to accumulate cerumen or lodge foreign bodies. In order to clean the ear canal or remove foreign bodies, three hands are required: one to brace the patient's head, one to maneuver the curette that is used to clean the ear, and one to hold a light source in order to make the small, dark area visible. Therefore, a design is needed that can allow a doctor to safely clean an ear with an instrument that only requires two hands. Furthermore, the design must have …

Nanomedicine Drug Delivery Across Mucous Membranes, Michael G. Lancina Iii

Theses and Dissertations

NANOMEDECINE DRUG DELIVERY ACROSS MUCOUS MEMBRANES

By Michael G. Lancina III

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.

Virginia Commonwealth Univeristy, 2017.

Major Director: Dr. Hu Yang, Associate Professor, Chemical and Life Science Engineering

Control over the distribution of therapeutic compounds is a complex and somewhat overlooked field of pharmaceutical research. When swallowing a pill or receiving an injection, it is commonly assumed that drug will spread throughout the body in a more or less uniform concentration and find its way to wherever it is needed. In …

Eye Movement Control: An Index For Athleticism, Brittany L. Oshea

Theses and Dissertations

Athletic potential is one of the most complex human traits. An elite athlete is produced from a complex interaction of an innumerable number of traits exhibited by the athlete. However, it’s not clear whether these traits are innate, allowing the athlete to excel, or, alternatively, are a consequence of practice. To be successful, athletes rely heavily on sensory information from the visual and vestibular systems. This study investigated the relationship eye movement control has with innate athleticism by comparing the saccadic and Vestibulo-Ocular Reflex (VOR) responses of former, no longer practicing, elite athletes against their age and gender matched counterparts …

Development & Validation Of An Improved Biomechanical Model For Motion Analysis, Darren Dawson

Theses

Three dimensional motion analysis systems are utilised across a number of different disciplines, including clinical gait analysis, sports performance studies and analysis of tasks of daily living. These systems utilise biomechanical models which define body segment coordinate systems and calculate kinematic and kinetic relationships about the joints between adjacent coordinate systems. In this study, a biomechanical model for general use in motion analysis was developed and validated. It was designed to improve upon the accuracy and capability of currently available models. The newly developed model utilises state of the art techniques to accurately define body segment coordinate systems. Accurate predictive …