Biomedical Devices and Instrumentation Commons^™

A Study Of Ciliary Beating In Chlamydomonas, Xin Li

Honors Capstone Projects - All

The goal of this research is to understand how a unicellular green alga, Chlamydomonas-reinhardtii, responds to red light (670nm) and sound waves, by monitoring the beating frequency of its two cilia, which control cell motility. Ciliary beating frequency (BF) is proportional to the production of ATP, mainly generated by photosynthesis. A photosynthesis inhibitor, 3-(3-, 4-dichlorophenyl)-1, 1-dimethylurea (DCMU) decreases ATP production by photosynthesis. I used DCMU as a tool to analyze the red light effect on BF.

In the process of studying the effect of red light, I unexpectedly discovered experimental conditions for unstable ciliary beating (as shown in the video). …

Development Of A Multi-Purpose Automated Synthesis Module For Production Of Novel Pet Radiopharmaceuticals, I Hong Shih

Dissertations & Theses (Open Access)

Among radiopharmaceuticals of positron emission tomography (PET), ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) made from commercialized automated synthesis module is the most frequently used in tumor diagnoses. But the false positive findings, such as infectious tissues and post-operative surgical conditions, show strong uptake of ¹⁸F-FDG in PET scans which requires extra clinical procedures to confirm the results. Moreover, the false negative findings, such as low glycolytic activity tumors, reduce the accuracy of PET scans. Therefore, there will be new PET radiopharmaceuticals to redeem the defects of ¹⁸FDG-PET applications.

Current commercialized automated synthesis modules are suitable for clinical use, but …

Humidity Effect On The Structure Of Electrospun Core-Shell Pcl-Peg Fibers For Tissue Regeneration Applications, Adam P. Golin

Electronic Thesis and Dissertation Repository

With the aim of creating a biodegradable scaffold for tympanic membrane (TM) tissue regeneration, core-shell nanofibers composed of a poly(caprolactone) shell and a poly(ethylene glycol) core were created using a coaxial electrospinning technique. In order to create fibers with an optimal core-shell morphology, the effect of relative humidity (RH) on the core-shell nanofibers was systematically studied, with a FITC-BSA complex encapsulated in the core to act as a model protein. The core-shell nanofibers were electrospun at relative humidity values of 20, 25, 30, and 40% RH within a glove box outfitted for humidity control. The core-shell morphology of the fibers …

Design And Development Of A Surgical Robot For Needle-Based Medical Interventions, Mostafa Hadavand

Electronic Thesis and Dissertation Repository

Lung cancer is the leading cause of cancer related deaths. If diagnosed in a timely manner, the treatment of choice is surgical resection of the cancerous lesions followed by radiotherapy. However, surgical resection may be too invasive for some patients due to old age or weakness. An alternative is minimally invasive needle-based interventions for cancer diagnosis and treatment. This project describes the design, analysis, development and experimental evaluation of a modular, compact, patient-mounted robotic manipulator for lung cancer diagnosis and treatment. In this regard, a novel parallel Remote Centre of Motion (RCM) mechanism is proposed for minimally invasive delivery of …

Drug Delivery To The Respiratory Tract Using Dry Powder Inhalers, Doaa M.R. Mossaad

Electronic Thesis and Dissertation Repository

Aerosols are an effective method to deliver therapeutic agents to the respiratory tract. Among aerosol generation systems, dry powder inhales have been attractive area of research for both local and systemic delivery of drugs. The challenge of any inhalation delivery system is to generate particles with an adequate range of particle sizes. In order to advance powder aerosol technologies, researchers have recognized the importance of investigating determinants affecting powder dispersion. The effect of particles’ surface characteristics, inhalation airflow rate, inhalation device, and development of an effective drug-carrier system are some of the fundamental areas that have been under investigation.

The …

Taper-Trunion Interface Stresses In Metal On Metal Hip Implants, Timothy L. Norman, Scott Gardner, Andrew Orton, Sharon Grafton, Thomas Fehring

The Research and Scholarship Symposium (2013-2019)

Metal on metal (MoM) total hip arthroplasty describes a hip joint replacement where a metal (cobalt chromium) femoral head articulates against a metal socket. This implant scenario has generally been successful until recently when larger (> 36 mm) metal heads have become more popular as a means to reduce the incidence of hip joint dislocation. Today, the number of clinical failures (described by fretting corrosion and a need for revision surgery) of MoM total hip arthroplasty is occurring at unacceptable rates. The objective of our research was to investigate the effect of horizontal lever arm (HLA), a geometric variable that …

Subtalar Fusion Fixture Design And Test, Nathan Ortiz

Honors Theses

Subtalar arthrodesis is performed when cartilage in the talo-calcaneal (the ankle) joint is degraded in a patient and there are multiple approaches to this surgery. Using synthetic bone material, fixtures were cast from aluminum, using the process of evaporation pattern casting, and epoxy. This casting was used to grip the calcaneus bone of the foot in order to load it mechanically, simulating different scenarios that would be encountered during walking. The relative displacement of the ankle joint was measured using a digital image correlation (DIC) program that was modified to work in both two- and three-dimensional space. This program can …

Markerless Analysis Of Upper Extremity Kinematics During Standardized Pediatric Assessment, Jacob R. Rammer

Master's Theses (2009 -)

Children with hemiplegic cerebral palsy experience reduced motor performance in the affected upper extremity and are typically evaluated based on degree of functional impairment using activity-based assessments such as the Shriners Hospitals for Children Upper Extremity Evaluation (SHUEE), a validated clinical measure, to describe performance prior to and following rehabilitative or surgical interventions. Evaluations rely on subjective therapist scoring techniques and lack sensitivity to detect change. Objective clinical motion analysis systems are an available but time-consuming and cost-intensive alternative, requiring uncomfortable application of markers to the patient. There is currently no available markerless, low-cost system that quantitatively assesses upper extremity …

Computational Evaluation Of Shear Stress And Restenosis In Stented Coronary Arteries Using Optical Coherence Tomography, Joshua K. Hughey

Master's Theses (2009 -)

The cause of coronary artery neointimal thickness (NT) leading to restenosis in ~10% of drug-eluting stents (DES) is unknown, but adverse wall shear stress (WSS) may contribute. Prior studies comparing WSS to restenosis for first generation DES yielded conflicting results, and cited different mechanisms of action for DES agents. Studies to date have not accounted for stent geometry, which dictates local WSS patterns influencing drug concentration. The objective of this investigation was to evaluate current generation stent platforms via their WSS patterns and their respective impact on NT. We prospectively enrolled 19 patients, who were randomized to thin-strut (81μm) 2-link …

Surface Acoustic Wave-Based Manipulation Of Intracellular Structures In Adherent Cultured Cells, Jeffrey Servetas

Honors College

A method for manipulating constituents of cells through the use of surface acoustic wave (SAW) devices is investigated. Cells are allowed to adhere to the gold surface of a SAW device, and the device is then operated at low power, with the intention of altering the distribution or activity of intracellular structures or organelles, while avoiding damage, or cell death. The method is compared to alternatives, such as optical tweezers, and pulsatile electrical stimulation.

Vicon Motion System, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.

Utilizing Fast Spin Echo Mri To Reduce Image Artifacts And Improve Implant/Tissue Interface Detection In Refractory Parkinson’S Patients With Deep Brain Stimulators, Subhendra N. Sarkar, Pooja R. Sarkar, Efstathios Papavassiliou, Rafael Rojas

Publications and Research

Introduction. In medically refractory Parkinson’s disease (PD) deep-brain stimulation (DBS) is an effective therapeutic tool. Postimplantation MRI is important in assessing tissue damage and DBS lead placement accuracy. We wanted to identify which MRI sequence can detectDBS leads with smallest artifactual signal void, allowing better tissue/electrode edge conspicuity.

Methods. Using an IRB approved protocol 8 advanced PDpatientswere imagedwithinMRconditional safety guidelines at lowRF power (SAR ≤ 0.1 W/kg) in coronal plane at 1.5T by various sequences.The image slices were subjectively evaluated for diagnostic quality and the lead contact diameters were compared to identify a sequence least affected by metallic leads.

Results …

Design Of Controlled Environment For Tissue Engineering, Malcolm Gerald Lapera

Master's Theses

Design of Controlled Environment for Tissue Engineering

Malcolm Lapera

Tissue engineering aims at relieving the need for donor tissue and organs by developing a process of creating viable tissues in the laboratory setting. With over 120,000 people awaiting a transplant, the need for generating tissue engineered organs is very large [3]. In order for organs to be engineered, a few issues need to be overcome. A work space that both creates an environment which maintains cell viability over an extended period of time as well as accommodates the necessary fabrication equipment will be needed to further tissue engineering research. Therefore, …

Biomechanical Performance Of Variable And Fixed Angle Locked Volar Plates For The Dorsally Comminuted Distal Radius, Patrick Atkinson, D. Martineau, J. Shorez, C. Beran, A. G. Dass

Mechanical Engineering Publications

Background

The ideal treatment strategy for the dorsally comminuted distal radius fracture continues to evolve. Newer plate designs allow for variable axis screw placement while maintaining the advantages of locked technology. The purpose of this study is to compare the biomechanical properties of one variable axis plate with two traditional locked constructs.

Methods

Simulated fractures were created via a distal 1 cm dorsal wedge osteotomy in radius bone analogs. The analogs were of low stiffness and rigidity to create a worst-case strength condition for the subject radius plates. This fracture-gap model was fixated using one of three different locked volar …

Sparse Signal Reconstruction From Polychromatic X-Ray Ct Measurements Via Mass Attenuation Discretization, Renliang Gu, Aleksandar Dogandžić

Aleksandar Dogandžić

We propose a method for reconstructing sparse images from polychromatic x-ray computed tomography (ct) measurements via mass attenuation coefficient discretization. The material of the inspected object and the incident spectrum are assumed to be unknown. We rewrite the Lambert-Beer’s law in terms of integral expressions of mass attenuation and discretize the resulting integrals. We then present a penalized constrained least-squares optimization approach forreconstructing the underlying object from log-domain measurements, where an active set approach is employed to estimate incident energy density parameters and the nonnegativity and sparsity of the image density map are imposed using negative-energy and smooth ℓ1-norm penalty …

Human Cardiovascular Responses To Artificial Gravity Variables: Ground-Based Experimentation For Spaceflight Implementation, Mark Howarth

Theses and Dissertations--Biomedical Engineering

One countermeasure to cardiovascular spaceflight deconditioning being tested is the application of intermittent artificial gravity provided by centripetal acceleration of a human via centrifuge. However, artificial gravity protocols have not been optimized for the cardiovascular system, or any other physiological system for that matter. Before artificial gravity protocols can be optimized for the cardiovascular system, cardiovascular responses to the variables of artificial gravity need to be quantified.

The research presented in this document is intended to determine how the artificial gravity variables, radius (gravity gradient) and lower limb exercise, affect cardiovascular responses during centrifugation. Net fluid (blood) shifts between body …

A Method To Modify Angle-Stable Intramedullary Nail Construct Compliance, Patrick Atkinson, B. P. Flanagan, D. Lecronier, M. R. Kubacki, P. Telehowski

Mechanical Engineering Publications

Traditional interlocked intramedullary (IM) nails have recently been modified to provide enhanced angular stability. These so-called ‘angle-stable’ IM nails are designed to eliminate construct toggle and also provide increased axial, bending, and torsional stiffness. While this added stability is needed for small fracture gaps to heal, angle-stable nails may be too stiff for large fracture gaps to unite. Even though relative stability is recommended for large fracture gaps, recent in vivo data indicates that traditional nails may allow for too much motion for healing to occur. The current study evaluated a modified technique for implanting an angle-stable nail which allows …

Microsphere Spray System For Wound Coverage, Nicholas J. Andersen

Theses and Dissertations--Biomedical Engineering

Spinal fusion is used to treat diseases or disorders of the spine by fusing together two or more vertebrae. Two associated risks with spinal fusion are infection and blood loss. Administration of tranexamic acid is used to prevent blood loss, and transfusions are given following blood loss. Surgical site infections are prevented with vancomycin powder spread into the surgical wound, while established infections are treated by debridement and delivery of antibiotics for 4 to 6 weeks. The present research explored an alternate method to prevent and treat blood loss or infection in spinal fusion. Poly(lactic-co-glycolic acid) (PLGA) microspheres was used …

Novel Technologies For The Detection And Mitigation Of Drowsy Driving, Samuel Lawoyin

Theses and Dissertations

In the human control of motor vehicles, there are situations regularly encountered wherein the vehicle operator becomes drowsy and fatigued due to the influence of long work days, long driving hours, or low amounts of sleep. Although various methods are currently proposed to detect drowsiness in the operator, they are either obtrusive, expensive, or otherwise impractical. The method of drowsy driving detection through the collection of Steering Wheel Movement (SWM) signals has become an important measure as it lends itself to accurate, effective, and cost-effective drowsiness detection. In this dissertation, novel technologies for drowsiness detection using Inertial Measurement Units (IMUs) …

Degradable Borate Glass Polyalkenoate Cements, L. Shen, A. Coughlan, Mark R. Towler, M. Hall

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass polyalkenoate cements (GPCs) containing aluminum-free borate glasses having the general composition Ag₂O-Na₂O-CaO-SrO-ZnO- TiO₂-B₂O₃ were evaluated in this work. An initial screening study of sixteen compositions was used to identify regions of glass formation and cement compositions with promising rheological properties. The results of the screening study were used to develop four model borate glass compositions for further study. A second round of rheological experiments was used to identify a preferred GPC formulation for each model glass composition. The model borate glasses containing higher levels of TiO₂ (7.5 mol %) …