Engineering Commons^™

A Model Microfluidics-Based System For The Human And Mouse Retina., Shawn Mishra, Ankush Thakur, Stephen Redenti, Maribel Vazquez

Publications and Research

The application of microfluidics technologies to the study of retinal function and response holds great promise for development of new and improved treatments for patients with degenerative retinal diseases. Restoration of vision via retinal transplantation therapy has been severely limited by the low numbers of motile cells observed post transplantation. Using modern soft lithographic techniques, we have developed the μRetina, a novel and convenient biomimetic microfluidics device capable of examing the migratory behavior of retinal lineage cells within biomimetic geometries of the human and mouse retina. Coupled computer simulations and experimental validations were used to characterize and confirm the formation …

The Role Of Bone Sialoprotein In Periodontal Tissue Development And Bone Repair, Yohannes Soenjaya

Electronic Thesis and Dissertation Repository

Bone development and repair involve complex processes that include interaction between cells and their surrounding matrix. In the body, bone sialoprotein (BSP) expression is up-regulated at the onset of mineralization. BSP is a multifunctional acidic phosphoprotein with collagen-binding, hydroxyapatite nucleating, and integrin recognition (RGD sequence, which is important for cell-attachment and signaling) regions. Mice lacking BSP expression (Bsp^-/-), exhibit a bone phenotype with reductions in bone mineral density, bone length, osteoclast activation, and impaired bone healing. This thesis examined the role of BSP in tooth development and also its potential use as a therapeutic reagent for bone …

Towards The Development Of A Wearable Tremor Suppression Glove, Yue Zhou

Electronic Thesis and Dissertation Repository

Patients diagnosed with Parkinson’s disease (PD) often associate with tremor. Among other symptoms of PD, tremor is the most aggressive symptom and it is difficult to control with traditional treatments. This thesis presents the assessment of Parkinsonian hand tremor in both the time domain and the frequency domain, the performance of a tremor estimator using different tremor models, and the development of a novel mechatronic transmission system for a wearable tremor suppression device. This transmission system functions as a mechatronic splitter that allows a single power source to support multiple independent applications. Unique features of this transmission system include low …

Effects Of Cell Adhesion Peptides, Ph, And Matrix Shape On Maintenance Of Breast Cancer Stem Cells In An Engineered Hydrogel Matrix, Leily Daneshian

Theses and Dissertations

Metastasis, resistance to chemo- and radiotherapy, and eventual relapse has been attributed to a tumor subpopulation known as cancer stem cells (CSCs). CSCs are regulated in their tumor microenvironment by various factors. Synthetic hydrogels can be used to investigate the effects of individual environmental factors on CSCs by providing inert 3D matrices. In this thesis, poly ethylene glycol diacrylate (PEGDA) hydrogel with 5kpa modulus has been used as a culture system to study the effect of; I) integrin and heparin binding peptides, 2) pH, and 3) the shape of the microenvironment on breast CSCs maintenance and tumorsphere formation in PEGDA. …

Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer

Douglas L Karlen

Quantifying energy issues associated with agricultural systems, even for a two-crop corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) rotation, is not a simple task. It becomes even more complicated if the goal is to include all aspects of sustainability (i.e., economic, environmental, and social). This Issue Paper examines energy issues associated with and affecting corn/soybean rotations by first defining the size of the system from both a U.S. and global perspective and then establishing boundaries based on the Farm Bill definition of sustainability. This structured approach is essential to help quantify energy issues within corn/soybean systems that …

Egf As A New Therapeutic Target For Medulloblastoma Metastasis, Jennifer Rico-Varela, Tanya Singh, Sean Mccutcheon, Maribel Vazquez

Publications and Research

Medulloblastoma (MB) is a malignant pediatric brain tumor known for its aggressive metastatic potential. Despite the well-documented migration of MB cells to other parts of the brain and spinal column, MB chemotaxis is poorly understood. Herein, we examined the in vitro migratory and cellular responses of MB-derived cells to external signaling of Epidermal Growth Factor (EGF), hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF-BB), and the stromal cellderived factors 1-alpha (SDF-1). Experiments utilized transwell assays and immunocytochemistry to identify receptor activation in MB migration, and used a microfluidic platform to examine directionality, trajectory, and gradient-dependence of motile cells. Data illustrates …

High Throughput Screening Of Priming Candidates For Impact On Nonviral Gene Delivery, Albert L. Nguyen

Department of Biological Systems Engineering: Dissertations and Theses

Priming, in the context of nonviral gene delivery, is the treatment of cells with a compound prior to gene transfer that enhances transfection efficiency and/or transgene expression. Essentially, it is the application of an adjuvant approach to gene delivery. Effective transfection strategies may require priming to compete with the efficiency of viral transduction in order to achieve clinically relevant efficiency and expression in vivo. To search for priming compounds, a high throughput screen of the NIH Clinical Collection was performed using 25kDa b-PEI, an EGFP/luciferase plasmid, and HEK293T cells. The EGFP reporter was multiplexed with Hoechst 33342 and Resazurin fluorescence …

Effect Of Tendon Vibration On Hemiparetic Arm Stability In Unstable Workspaces, Megan O. Conrad, Bani Gadhoke, Robert A. Scheidt, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Sensory stimulation of wrist musculature can enhance stability in the proximal arm and may be a useful therapy aimed at improving arm control post-stroke. Specifically, our prior research indicates tendon vibration can enhance stability during point-to-point arm movements and in tracking tasks. The goal of the present study was to investigate the influence of forearm tendon vibration on endpoint stability, measured at the hand, immediately following forward arm movements in an unstable environment. Both proximal and distal workspaces were tested. Ten hemiparetic stroke subjects and 5 healthy controls made forward arm movements while grasping the handle of a two-joint robotic …

Spectral And Temporal Interrogation Of Cerebral Hemodynamics Via High Speed Laser Speckle Contrast Imaging, Rex Chin-Hao Chen

Theses and Dissertations

Laser Speckle Contrast Imaging (LSCI) is a non-scanning wide field-of-view optical imaging technique specifically developed for cerebral blood flow (CBF) monitoring. In this project, a versatile Laser speckle contrast imaging system has been designed and developed to monitor CBF changes and examine the physical properties of cerebral vasculature during functional brain activation experiments.

The hardware of the system consists of a high speed CMOS camera, a coherent light source, a trinocular microscope, and a PC that does camera controlling and data storage. The simplicity of the system’s hardware makes it suitable for biological experiments.

In controlled flow experiments using a …

Supervised Machine Learning For Classification Of The Electrophysiological Effects Of Chronotropic Drugs On Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes, Christopher Heylman, Rupsa Datta, Agua Sobrino, Steven George, Enrico Gratton

Biomedical Engineering

Supervised machine learning can be used to predict which drugs human cardiomyocytes have been exposed to. Using electrophysiological data collected from human cardiomyocytes with known exposure to different drugs, a supervised machine learning algorithm can be trained to recognize and classify cells that have been exposed to an unknown drug. Furthermore, the learning algorithm provides information on the relative contribution of each data parameter to the overall classification. Probabilities and confidence in the accuracy of each classification may also be determined by the algorithm. In this study, the electrophysiological effects of β–adrenergic drugs, propranolol and isoproterenol, on cardiomyocytes derived from …

An Intra-Bone Axial Load Transducer: Development And Validation In An In-Vitro Radius Model, Nikolas K. Knowles, Michael Gladwell, Louis M. Ferreira

Surgery Publications

Background

Accurate measurement of forces through the proximal radius can assess the effects of some surgical procedures on radioulnar load sharing, but is difficult to achieve given the redundant loading nature of the musculoskeletal system. Previously reported devices have relied on indirect measurements that may alter articular joint location and function. An axial load transducer interposed in the diaphysis of the radius may accurately quantify unknown axial loads of the proximal radius, and maintain articular location.

Methods

An in-vitro radius model was developed by interposing an axial load transducer in the diaphysis of the proximal radius. Static loads of 20, …

Investigation Of The Inherent Chemical, Structural, And Mechanical Attributes Of Bio-Engineered Composites Found In Nature: Alligator Gar’S Exoskeleton Fish Scales, Wayne Derald Hodo

Graduate Theses and Dissertations

The U.S. Army has determined a huge cost savings of up to 51% can be accomplished by reducing the gross vehicle weight, for their personnel carrier, by 33%. To cut cost, composite materials are needed. Man-made composites can have superior material properties (high-strength, high-fracture toughness, and lightweight), but they are prone to delamination at the glued-layered interface. In contrast, fish scale is a natural composite that has the same material properties and, additionally, tend not to delaminate.

The focus of this study was to learn how nature integrates hard and soft materials at each length scale to form a layered …

Phospho1 Deficiency Transiently Modifies Bone Architecture Yet Produces Consistent Modification In Osteocyte Differentiation And Vascular Porosity With Ageing, Behzad Javaheri, Alessandra Carriero, Katherine Ann Staines, Y.-M. Chang, D. A. Houston, Karla J. Oldknow, José Luis Millán, Bassir N. Kazeruni, Phil L. Salmon, Sandra J. Shefelbine

Biomedical Engineering and Sciences Faculty Publications

PHOSPHO1 is one of principal proteins involved in initiating bone matrix mineralisation. Recent studies have found that Phospho1 KO mice ( Phospho1-R74X) display multiple skeletal abnormalities with spontaneous fractures, bowed long bones, osteomalacia and scoliosis. These analyses have however been limited to young mice and it remains unclear whether the role of PHOSPHO1 is conserved in the mature murine skeleton where bone turnover is limited. In this study, we have used ex-vivo computerised tomography to examine the effect of Phospho1 deletion on tibial bone architecture in mice at a range of ages (5, 7, 16 and 34. weeks of age) …

The Effect Of Recency To Human Mobility, Hugo Barbosa, Fernando B. De Lima-Neto, Alexandre Evsukoff, Ronaldo Menezes

Biomedical Engineering and Sciences Faculty Publications

In recent years, we have seen scientists attempt to model and explain human dynamics and in particular human movement. Many aspects of our complex life are affected by human movement such as disease spread and epidemics modeling, city planning, wireless network development, and disaster relief, to name a few. Given the myriad of applications, it is clear that a complete understanding of how people move in space can lead to considerable benefits to our society. In most of the recent works, scientists have focused on the idea that people movements are biased towards frequently-visited locations. According to them, human movement …

Storage Of Round And Square Switchgrass Bales: Effect Of Storage Time And Fungal Inoculation On Saccharification Efficiency, Noaa Frederick

Graduate Theses and Dissertations

To produce fermentable sugars from lignocellulosic biomass feedstock, severe pretreatment conditions are needed (either high acid concentration, temperature, or retention times). High severities can produce toxic byproducts which inhibit enzymatic hydrolysis or fermentation. In order to reduce pretreatment severities (and thus increase enzyme and fermentation efficiency), the white-rot fungus Pleurotus ostreastus was seeded into square and round bales of Kanlow switchgrass (Panicum virgastum L.) and left in the field over a period of 9 month. The laccase producing fungus is believed to selectively degrade lignin, a common plant structural polymer, which can function as an enzymatic inhibitor. Samples were taken …

Modulation Of Valve Interstitial Cell Function Through Cell Shape And Phenotype, Atefeh Razavi

Graduate Theses and Dissertations

The aortic valve is a highly dynamic structure responding to actively to the chemical, mechanical and physical cues of the valve microenvironment. Valve interstitial cells are dispersed throughout the valve tissue and play an important role in maintaining the integrity and optimum function of the valve. They are a heterogeneous population composed of various phenotype. These phenotypes have specific functions characteristic of valve physiological and pathological conditions. The effect of mechanical loading and chemical modulators on the behavior of the valve interstitial cells have largely been studied. However the role of valve interstitial cell shape as an intrinsic physical cue …

Rupture In Abdominal Aortic Aneurysm, Qusay Alfaori

Graduate Theses and Dissertations

Quantification of abdominal aortic aneurysm development, its growth kinetics, and rupture criteria are important to decrease the risk of this life-threatening event. Uniaxial testing of healthy and collagen degraded aortic specimens from pigs was performed. A mathematical model, from the literature, for the stress-strain relationship that is suitable for describing the behavior of abdominal aortic tissue was used to derive specific tissue properties/parameters as a function of strain rate and as a function of specimen orientation. Analyses consisting of Finite Element Modeling of healthy and collagen degraded abdominal aortas were performed using ABAQUS finite element code and the measured properties. …

Image Processing And Visualization Of Terahertz Pulsed Imaging Of Breast Cancer Tumors, Yuhao Wu

Graduate Theses and Dissertations

Terahertz imaging technology has grown substantially in recent years. With new advances made in the generation, manipulation, and detection of terahertz radiation, terahertz imaging has found its application as inspection tools in a wide range of areas including biomedicine, materials science, and aerospace industries. In the field of medical imaging, terahertz (THz) has emerged as a new imaging modality due to some fundamental physical properties of the THz wave. THz imaging has been used to examine various biological structures, and THz tomography has been developed to probe the 3D structures of those samples.

THz pulsed imaging (TPI) is one of …

Background Differences In Baseline And Stimulated Mmp Levels Influence Abdominal Aortic Aneurysm Susceptibility, Matthew A. Dale, Melissa K. Suh, Shijia Zhao, Trevor Meisinger, Linxia Gu, Vicki J. Swier, Devendra K. Agrawal, Timothy Greiner, Jeffrey S. Carson, B. Timothy Baxter, Wanfen Xiong

Department of Mechanical and Materials Engineering: Faculty Publications

Objective: Evidence has demonstrated profound influence of genetic background on cardiovascular phenotypes. Murine models in Marfan syndrome (MFS) have shown that genetic background-related variations affect thoracic aortic aneurysm formation, rupture, and lifespan of mice. MFS mice with C57Bl/6 genetic background are less susceptible to aneurysm formation compared to the 129/SvEv genetic background. In this study, we hypothesize that susceptibility to abdominal aortic aneurysm (AAA) will be increased in 129/SvEv mice versus C57Bl/6 mice. We tested this hypothesis by assessing differences in aneurysm size, tissue properties, immune response, and MMP expression.

Methods: Mice of C57Bl/6 or 129/SvEv background underwent AAA induction …

Midfield Rf Signal Detector, Dawei Zhang

Electrical Engineering

This project is part of a Master’s thesis which looks at alternative ways to measure blood glucose. The Master’s thesis uses mid-field signals in order to match impedance and therefore lose less power as they travel through flesh. The goal of this senior project is to build a receiver for those signals and give accurate RSSI (received signal strength indicator) measurements. Mid-fields were originally explored by Stanford professor Dr. Ada Poon [3] who used the signaling technique to recharge the batteries of deeply implanted devices. Devices implanted near the surface of the skin were able to have their batteries recharged …

Retinal Architecture In ​Rgs9- And ​R9ap-Associated Retinal Dysfunction (Bradyopsia), Rupert W. Strauss, Adam M. Dubis, Robert F. Cooper, Rola Ba-Abbad, Anthony T. Moore, Andrew R. Webster, Alfredo Dubra, Joseph Carroll, Michel Michaelides

Biomedical Engineering Faculty Research and Publications

Purpose

To characterize photoreceptor structure and mosaic integrity in subjects with RGS9- and R9AP-associated retinal dysfunction (bradyopsia) and compare to previous observations in other cone dysfunction disorders such as oligocone trichromacy.

Design

Observational case series.

Methods

setting: Moorfields Eye Hospital (United Kingdom) and Medical College Wisconsin (USA). study population: Six eyes of 3 subjects with disease-causing variants in RGS9 or R9AP. main outcome measures: Detailed retinal imaging using spectral-domain optical coherence tomography and confocal adaptive-optics scanning light ophthalmoscopy.

Results

Cone density at 100 μm from foveal center ranged from 123 132 cones/mm²to 140 013 cones/mm^{2 …}

When 1 + 1 > 2: Nanostructured Composites For Hard Tissue Engineering Applications, Vuk Uskoković

Pharmacy Faculty Articles and Research

Multicomponent, synergistic and multifunctional nanostructures have taken over the spotlight in the realm of biomedical nanotechnologies. The most prospective materials for bone regeneration today are almost exclusively composites comprising two or more components that compensate for the shortcomings of each one of them alone. This is quite natural in view of the fact that all hard tissues in the human body, except perhaps the tooth enamel, are composite nanostructures. This review article highlights some of the most prospective breakthroughs made in this research direction, with the hard tissues in main focus being those comprising bone, tooth cementum, dentin and enamel. …

Feasibility Of Using Raman-Based Techniques For Breast Cancer Detection, Sara Mollamohammada

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Breast cancer is one of the common types of cancer among women all over the world. Early diagnosis is an effective way that improve the treatment process and gives the patients a better chance of survival. Many of the patients infected by breast cancer choose breast conservation surgery (BCS). However, some of those will be subjected to mastectomy, and many will have tumor recurrence as there is no precise technique to show the tumor margins. Raman-based methods are powerful techniques with potential to rapidly differentiate normal from tumor tissues and provides a solution to detect tumor margin. This is because …

Design And Development Of A Wearable Wireless Health Monitoring System: A Smart Watch Approach, Keerthi Paranikumar

Graduate Theses and Dissertations

According to Statistics, every year, about 610,000 people die because of heart disease in United States of America. (i.e. 1 in every 4 deaths.*) Heart disease is common for both men and women. Annually, about 370,000 people die because of coronary heart disease, which is the most common type of heart disease [1]. About 735,000 Americans have heart attack every year. In this, 210,000 people gets heart attack who already has heart problems and 525,000 people get heart attack for the first time [2]. Not many people know that they have heart problems. Around 47% of the people in United …

Effects Of Varus Knee Alignment And Using Toe-Cages On Frontal Plane Knee Biomechanics In Stationary Cycling, Guangping Shen

Masters Theses

Effects of varus knee alignment on the internal knee abduction moment (KAM) in walking has been widely studied. KAM has been shown to be closely associated with the development of medial knee osteoarthritis (OA). Despite the importance of the knee alignment, no studies have explored its effects on knee frontal plane biomechanics during stationary cycling. The purpose of this study was to examine the effects of varus knee alignment and using a toe-cage on the knee frontal plane biomechanics during stationary cycling. Eleven participants in each of the varus and neutral groups participated in the study. The participants performed in …

Icloudecg: A Mobile Cardiac Telemedicine System, David S. Clifford

Masters Theses

With rising healthcare costs and a substantially growing number of patients 65 or over, the benefits of telemedicine and patient self-monitoring systems are becoming increasingly evident. Patients, physicians, hospitals, and even insurance providers benefit from vigilant, cost-effective patient monitoring systems. This thesis describes the development of a portable, smart-phone connected system for continuous cardiac monitoring. The system is capable of continuously monitoring the conditions of the heart, automated detection of cardiac arrhythmias, and real-time notifying patients and physicians of the detected abnormalities. The system consists of four main subsystems: 1) a Bluetooth capable chest-strap ECG, 2) an Android-enabled mobile device, …

Removal Of Trace Organic Compounds In Domestic Wastewater Using Recirculating Packed-Bed Media Filters, Brittani Nikole Perez

Masters Theses

Pharmaceuticals and personal care products (PPCPs) are commonly detected in the environment resulting from their survival from conventional wastewater treatment systems. More information is needed about the fate and transfer of these trace organic compounds in domestic wastewater and their associated risks so that efficient strategies for their removal can be developed for both large/small scale treatment systems. This study aimed to determine whether onsite wastewater treatment systems were capable of providing PPCP removal, in addition to quantifying different forms of removal (biodegradation/sorption). A column study was constructed to determine the removal efficiencies of 3 target PPCPs, endocrine disrupting compound …

Voxel-Level Absorbed Dose Calculations With A Deterministic Grid-Based Boltzmann Solver For Nuclear Medicine And The Clinical Value Of Voxel-Level Calculations, Justin Mikell

Dissertations & Theses (Open Access)

Voxel-level absorbed dose (VLAD) is rarely calculated for nuclear medicine (NM) procedures involving unsealed sources or 90Y microspheres (YM). The current standard of practice for absorbed dose calculations in NM utilizes MIRD S-values, which 1) assume a uniform distribution in organs, 2) do not use patient specific geometry, and 3) lack a tumor model. VLADs overcome these limitations. One reason VLADs are not routinely performed is the difficulty in obtaining accurate absorbed doses in a clinically acceptable time. The deterministic grid-based Boltzmann solver (GBBS) was recently applied to radiation oncology where it was reported as fast and accurate for both …

Increased Lower Limb Spasticity But Not Strength Or Function Following A Single-Dose Serotonin Reuptake Inhibitor In Chronic Stroke, Krishnaj Gourab, Brian D. Schmit, T. George Hornby

Biomedical Engineering Faculty Research and Publications

Objective: To investigate the effects of single doses of a selective serotonin reuptake inhibitor (SSRI) on lower limb voluntary and reflex function in individuals with chronic stroke.

Design: Double-blind, randomized, placebo-controlled crossover trial.

Setting: Outpatient research setting.

Participants: Individuals (N=10; 7 men; mean age ± SD, 57±10y) with poststroke hemiplegia of >1 year duration who completed all assessments.

Interventions: Patients were assessed before and 5 hours after single-dose, overencapsulated 10-mg doses of escitalopram (SSRI) or placebo, with 1 week between conditions.

Main Outcome Measures: Primary assessments included maximal ankle and knee isometric strength, and velocity-dependent (30°/s–120°/s) plantarflexor stretch reflexes under …

Prediction Of Rupture In Abdominal Aortic Aneurysm, Qusay Alfaori

Graduate Theses and Dissertations

Studying the development of abdominal aortic aneurysm (AAA) through quantification of its growth kinetics and rupture criteria is important to decrease the risk of this life-threatening event. Uniaxial and biaxial testing of healthy and time-dependent Type-I collagen degraded aortic specimens from pigs was performed. Stress-strain suitable mathematical models describing the behavior of abdominal aortic tissue were utilized to derive specific tissue properties and parameters. Reduction in Type-I collagen fraction was observed using picrosirius red staining method, bright field microscopy, and MATLAB. Finite Element Modeling (FEM) of healthy and time-dependent Type-I collagen degraded abdominal aortas were performed using ABAQUS finite element …