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 The results of this project are of a confidential nature and will not be published at this time.

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 …

Portable Polarimetric Fiber Stress Sensor System For Visco-Elastic And Biomimetic Material Analysis, Mark C. Harrison, Andrea M. Armani

Engineering Faculty Articles and Research

Non-destructive materials characterization methods have significantly changed our fundamental understanding of material behavior and have enabled predictive models to be developed. However, the majority of these efforts have focused on crystalline and metallic materials, and transitioning to biomaterials, such as tissue samples, is non-trivial, as there are strict sample handling requirements and environmental controls which prevent the use of conventional equipment. Additionally, the samples are smaller and more complex in composition. Therefore, more advanced sample analysis methods capable of operating in these environments are needed. In the present work, we demonstrate an all-fiber-based material analysis system based on optical polarimetry. …

A Comparative Evaluation Of Cadaveric And Composite Femur Models For Total Hip Arthroplasty, Anderson Lynn Adams

Graduate Theses - Biology & Biomedical Engineering

Composite bones are often used in testing of orthopedic implants due to their relative ease of use and low inter-specimen variability when compared to cadaveric bones. Tests were run to ensure that the composite bones remained an acceptable model for cadaver bones throughout surgical manipulation. Composite (n=6) and cadaver (n=6) femur specimen were subjected to a total hip arthroplasty (THA). Flexural rigidity, axial stiffness, and axial strain measurements were taken at various stages in the surgical process. The composite and cadaver specimen were not found to behave similarly in either flexural rigidity or axial stiffness tests. The results showed a …

Evaluating The Effectiveness Of Cranial Molding For Treatment Of Positional Plagiocephaly Using Finite Element Analysis, Maziyar Keshtgar

Master's Theses

Since the advent of recommendations for placing infants in the supine position during sleep to reduce the incidence of sudden infant death syndrome, clinicians have noted an increase in the frequency of cranial asymmetry due to deformation of suture sections of the infants’ skulls as a result of constant concentrated stress in one area at the back of their head. This specific form of cranial deformation is known as positional plagiocephaly and its rate of occurrence has increased from 0.3% in 8.2% within the past 30 years.

Current treatments and methodologies for preventing and correcting positional plagiocephaly such as stretching …

Modeling The Contributions Of Hand Loads To Cervical Spine Compressive Forces, Mohamed R.S. Amar

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

The purpose for this study is threefold. All involve single handed lifting tasks where the height of the lifted object, the distance of the lifted object from the body, and the angle of the lift relative to the body were varied. First, examine the activity of each of the shared musculature of selected shared muscles between the shoulder and cervical spine. Second, attempt to empirically model the activations of the shared muscles. Third, to understand the relationship between the active and antagonistic contraction. Finally, to establish a biomechanical model to estimate the compressive forces on the cervical spine.

Ten subjects …

Characterization Of Low Density Intracranial Lesions Using Dual-Energy Computed Tomography, Jessica L. Nute

Dissertations & Theses (Open Access)

Calcific and hemorrhagic foci of susceptibility are frequently encountered on routine brain MR studies. Both etiologies cause variations in local magnetic field strength, leading to dark regions on the MR images that cannot be classified. Single-energy CT (SECT) can be used to identify lesions with attenuation over 100 HU as calcific, however lesions with lower attenuation cannot be reliably identified. While calcific lesions are unlikely to cause harm, hemorrhagic lesions carry a risk of subsequent intracranial bleeding; as such, identification of hemorrhage is vital in preventing the inappropriate use of anticoagulant medications in patients with hemorrhagic lesions.

Given there currently …

Development Of Point-Of-Care Testing Sensors For Biomarker Detection, Xuena Zhu

FIU Electronic Theses and Dissertations

Point-of-care testing (POCT) is defined as medical testing at or near the site of patient care and has become a critical component of the diagnostic industry. POCT has many advantages over tests in centralized laboratories including small reagent volumes, small size, rapid turnaround time, cost-effectiveness, low power consumption and functional integration of multiple devices. Paper-based POCT sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for clinical diagnosis.

The focus of this dissertation was to develop simple, rapid and low cost paper-based POCT sensors with high sensitivity and portability for disease biomarker detection. Lateral …

Development Of A Neuromusculoskeletal Computer Model In A Chondrodystrophic Dog., Gregory Russo States

Electronic Theses and Dissertations

Intervertebral disc disease (IVDD) is a naturally occurring disease in dogs that produces a spontaneous injury to the spinal cord. IVDD is characterized by mineralization of the intervertebral disc nucleus pulposus, which reduces its load bearing capacity and results in high rates of intervertebral disc herniation (IVDH). IVDH is disproportionately present in Dachshunds compared to other breeds, affecting an estimated 1 in 5 Dachshunds during their lifetime (Levine, J. M. et al., 2011). Assessment of injury severity and recovery in animal models is generally performed using a point scale, where subjects are graded according to metrics such as pain perception, …

Effects Of Three Dry Powder Inhalers On Deposition Of Aerosolized Medicine In The Human Oral-Pharyngeal-Laryngeal Regions, Mohammed Ali

Technology Faculty Publications and Presentations

The dry powder inhaler (DPI) is a popular, effective and convenient drug delivery device for inhalation therapy to treat asthma. However, a large quantity (approximately 54%) of inhaled aerosols deposit in the oropharyngeal region. Deposition in this region is undesirable because it provides minimum therapeutic benefits and has adverse localized or systemic side effects. This study reports a method of examining electrostatic charge effects on deposition of three DPI aerosols (Spiriva^™ Handihaler, Advair Diskus^™, and Pulmicort^™ Turbohaler) in a cadaver-based cast of the human oral-pharyngeal-laryngeal (OPL) regions. Experimental aerosols were generated from the three commercially available …

Collagen Crosslinking Reagent Utilized To Modify The Mechanical Properties Of The Soft Palate In Equine Snoring And Apnea Applications, Stephanie L. Hunt

Theses and Dissertations--Biomedical Engineering

Snoring is a sleep disruption that can lead to obstructive sleep apnea (OSA), which interrupts breathing by obstructing the airway. Injecting a protein crosslinker, such as genipin, into the soft palate could decrease the severity of snoring and OSA by stiffening the soft palate. Equine soft palates modeled human palates due to a high incidence of awake snoring and apnea.

The pilot in vivo study treated six horses with two 100 mM injections of the buffered genipin reagent. The efficacy phase horses underwent respiratory audio recordings to document snoring changes using Matlab and ImageJ in the time and frequency domains. …

Primary Cilia Mechanotransduction And Microtubule Stability In Mechanically Stretched Lung Adenocarcinoma Cells, Monika Rassi Radhika

Theses and Dissertations

The objective of this study is to investigate the role of microtubule based organelle, the primary cilia in lung adenocarcinoma by i) Quantifying the presence of primary cilia in several Non Small Cell Lung Cancer (NSCLC) cell lines in response to mechanical stimuli, ii) Attempting to determine the role of primary cilia in cell migration, iii) Investigating the effects of Paclitaxel(Taxol) resistance in lung cancer cells, iv) Analyzing the response of lung cancer cells to Smoothened Inhibitors and v) Determining the effects of Transforming Growth Factor Beta-1(TGF-β1) induced Epithelial to Mesenchymal Transition(EMT) in lung cancer cells. To ascertain the effects …

Characterization Of Closed Head Impact Injury In Rat, Yi Hua, Praveen Akula, Matthew Kelso, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The closed head impact (CHI) rat models are commonly used for studying the traumatic brain injury. The impact parameters vary considerably among different laboratories, making the comparison of research findings difficult. In this work, numerical CHI experiments were conducted to investigate the sensitivities of intracranial responses to various impact parameters (e.g., impact depth, velocity, and position; impactor diameter, material, and shape). A three-dimensional finite element rat head model with anatomical details was subjected to impact loadings. Results revealed that impact depth and impactor shape were the two leading factors affecting intracranial responses.The influence of impactor diameter was region-specific and an …

Long Term Blood Oxygenation Membranes, Joseph V. Alexander

Theses and Dissertations--Biomedical Engineering

Hollow fiber membranes are widely used in blood oxygenators to remove carbon dioxide and add oxygen during cardiopulmonary bypass operations. These devices are now widely used off-label by physicians to perform extracorporeal blood oxygenation for patients with lung failure. Unfortunately, the hollow fiber membranes used in these devices fail prematurely due to blood plasma leakage and gas emboli formation.

This project formed ultrathin (~100nm) polymer coatings on polymer hollow fiber membranes. The coatings were intended to “block” existing pores on the exterior surfaces while permitting high gas fluxes. This coating is synthesized using surface imitated control radical polymerization.

The coating …

Blast-Induced Mild Traumatic Brain Injury Through Ear Canal: A Finite Element Study, Praveen Akula, Yi Hua, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose The role of ear canal in transmitting blast waves to the brain is not clear. The goal of this work is to characterize the influence of ear canal on blast-induced mild traumatic brain injury through a computational approach.

Methods A three-dimensional human head model with single-side ear canal details was reconstructed from computed tomography images. The ear canal was positioned either facing the incident blast wave or facing away from the blast wave.

Results The blast wave-head interaction has demonstrated that the overpressure within the ear canal was substantially amplified when the ear directly faced the blast wave. When …

Systematic Study Of The Biological Effects Of Nitric Oxide (No) Using Innovative No Measurement And Delivery Systems, Weilue He

Dissertations, Master's Theses and Master's Reports

Nitric oxide (NO) is recognized as the most important small signaling molecule in the human body. An imbalance of NO is closely associated with many serious diseases such as neurological disorders, cardiovascular diseases, chronic inflammations and cancers. Herein two chemiluminescence-based devices (a real-time NO measurement device and a controllable NO delivery device) were developed to facilitate the NO quantitative study and obtain information for NO related drug design.

The first device used for real-time measuring NO(g) flux from living cells was developed and validated. The principle was to use a two-chamber design, with a cell culture chamber and a gaseous …

Human Cardiovascular Responses To Simulated Partial Gravity And A Short Hypergravity Exposure, Qingguang Zhang

Theses and Dissertations--Biomedical Engineering

Orthostatic intolerance (OI), i.e., the inability to maintain stable arterial pressure during upright posture, is a major problem for astronauts after spaceflight. Therefore, one important goal of spaceflight-related research is the development of countermeasures to prevent post flight OI. Given the rarity and expense of spaceflight, countermeasure development requires ground-based simulations of partial gravity to induce appropriate orthostatic effects on the human body, and to test the efficacy of potential countermeasures.

To test the efficacy of upright lower body positive pressure (LBPP) as a model for simulating cardiovascular responses to lunar and Martian gravities on Earth, cardiovascular responses to upright …

Unlocking The Secrets Of Multi-Flagellated Propulsion, Stefan Oma Nwandu-Vincent

Doctoral Dissertations

In this work, unique high-speed imaging platforms and an array of theoretical analysis methods are used to thoroughly investigate eukaryotic multi-flagellated propulsion using Tritrichomonas foetus as a test case. Through experimental observations through our imaging system with superior resolution and capture rate exceeding that of previous studies, it was discovered for the first time that the T. foetus employs a strategy similar to that of the “run and tumble” strategies found in bacteria and Chlamydomonas; it has two distinct flagellar beating patterns that result in two different body swimming motions, linear and turning swimming.

These two flagella patterns were …

Smooth Muscle Cell Organization In The Stem Region Of The Gracilis Collateral Circulation In Balb/C Mice, Laura Lenae Burckhardt

Biomedical Engineering

Of the approximately 8 million Americans who suffer from ischemic peripheral arterial occlusive disease (PAOD), many present with intermittent claudication, or pain associated with exercise. Impaired vasodilation of resistance vessels is a potential explanation for this symptom. Occluded arteries can lead to increased flow through collateral vessels, which function as natural bypasses around the obstruction. This increase in blood flow and resulting shear stress can cause outward remodeling, or arteriogenesis, which improves the efficacy of collaterals. However, following femoral artery ligation in a mouse model of chronic ischemia, vasodilation in the stem region of collateral vessels is impaired at day …

The Effect Of Artery Bifurcation Angles On Fluid Flow And Wall Shear Stress In The Middle Cerebral Artery, Zachary Ramey Jones

Master's Theses

Saccular aneurysms are the abnormal plastic deformation of veins and arteries that can lead to lethal thrombus genesis or internal hemorrhaging. Medication and surgery greatly reduce the mortality rates, but treatment is limited by predicting who will develop aneurysms. A common location for saccular aneurysm genesis is at the main middle cerebral artery (MCA) bifurcation. The main MCA bifurcation is comprised of the M1 MCA segment, parent artery, and two M2 segments, daughter arteries. Studies have found that the lateral angle (LA) ratio of the MCA bifurcation is correlated with aneurysm formation. The LA ratio is defined as the angle …

A Highly Adaptive And Cost Effective Second Generation Incubator (Sgi) Towards Educational, Research And Clinical Processes, Yassir H. Al-Sayagh

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

Today´s rising demand for more reliable and affordable alternatives to organ transplant has led to a growing market for in vitro tissue culture systems. The main objective of tissue engineering as a whole is to employ human tissue equivalents for commercial use. The state-of-the-art processes for producing these so called tissue models are still very expensive, difficult to produce and time-consuming.

To engineer tissues, in vitro, a three-dimensional support structure commonly termed scaffold is needed. Stem cells are then added to the scaffold. In order for tissue to materialize, the scaffold and the cells must be incubated (cultured) at a …

Movement Effects On The Flow Physics And Nutrient Delivery In Engineered Valvular Tissues, Manuel Salinas

FIU Electronic Theses and Dissertations

Mechanical conditioning has been shown to promote tissue formation in a wide variety of tissue engineering efforts. However the underlying mechanisms by which external mechanical stimuli regulate cells and tissues are not known. This is particularly relevant in the area of heart valve tissue engineering (HVTE) owing to the intense hemodynamic environments that surround native valves. Some studies suggest that oscillatory shear stress (OSS) caused by steady flow and scaffold flexure play a critical role in engineered tissue formation derived from bone marrow derived stem cells (BMSCs). In addition, scaffold flexure may enhance nutrient (e.g. oxygen, glucose) transport. In this …

Neuromuscular Changes In Older Adults During The Lateral Step Task, Tatiana Bejarano

FIU Electronic Theses and Dissertations

Older adults may have trouble when performing activities of daily living due to decrease in physical strength and degradation of neuromotor and musculoskeletal function. Motor activation patterns during Lateral Step Down and Step Up from 4-inch and 8-inch step heights was assessed in younger (n=8, 24.4 years) and older adults (n=8, 58.9 years) using joint angle kinematics and electromyography of lower extremity muscles. Ground reaction forces were used to ascertain the loading, stabilization and unloading phases of the tasks. Older adults had an altered muscle activation sequence and significantly longer muscle bursts during loading for the tibialis anterior, gastrocnemius, vastus …

Characterization Of A Contact-Stylus Surface Digitization Method Using Collaborative Robots: Accuracy Evaluation In The Context Of Shoulder Replacement Or Resurfacing, Sara Saud Zimmo

Electronic Thesis and Dissertation Repository

Total shoulder arthroplasty (TSA) is the third most common joint replacement. While robot-assisted hip and knee replacement technologies have enjoyed extensive development, this has been limited in the upper limb. This work focused on quantifying the localization accuracy of a robotic system, and evaluating its efficacy in the context of TSA.

A collaborative robot was fitted with a stylus tip to perform manual surface digitizations using the robot’s encoder output. In the first experiment, two precision-machined master cubes, representing the working volume around a glenoid structure, were used for system validation. Next, cadaveric glenoids were digitized and compared to a …

Finite Element Modeling Of The Proximal Humerus To Compare Stemless, Short And Standard Stem Humeral Components Of Varying Material Stiffness For Shoulder Arthroplasty, Najmeh Razfar

Electronic Thesis and Dissertation Repository

In patients with debilitating pain due to osteoarthritis, total shoulder arthroplasty can restore function and provide effective pain relief. Newer implant designs vary in length and material stiffness. Unfortunately, literature on these newer implants is limited. This thesis investigates the effect of stem length and implant material stiffness on proximal humeral bone stresses. 3D bone models with implants of various stem lengths (stemless, short, and standard) and different material stiffness’s (CoCr, Ti and PEEK) were generated using MIMICS, Solidworks and ABAQUS for varying abduction angles (15°, 45° and 75°). Cortical and trabecular stresses were contrasted with the intact bone state. …

Visual Perception And Cognition In Image-Guided Intervention, Kamyar Abhari

Electronic Thesis and Dissertation Repository

Surgical image visualization and interaction systems can dramatically affect the efficacy and efficiency of surgical training, planning, and interventions. This is even more profound in the case of minimally-invasive surgery where restricted access to the operative field in conjunction with limited field of view necessitate a visualization medium to provide patient-specific information at any given moment. Unfortunately, little research has been devoted to studying human factors associated with medical image displays and the need for a robust, intuitive visualization and interaction interfaces has remained largely unfulfilled to this day. Failure to engineer efficient medical solutions and design intuitive visualization interfaces …

Nerve Fiber Diameter Measurements Using Hematoxylin And Eosin Staining And Brightfield Microscopy To Assess The Novel Method Of Characterizing Peripheral Nerve Fiber Distributions By Group Delay, Jorge Arturo Vazquez

Master's Theses

Peripheral neuropathies are a set of common diseases that affect the peripheral nervous system, causing damage to vital connections between various parts of the body and the brain and spinal cord. Different clinical conditions are known to selectively impact various size nerve fibers, which often makes it difficult to diagnose which peripheral neuropathy a patient might have. The nerve conduction velocity diagnostic test provides clinically useful information in the diagnosis of some peripheral neuropathies. This method is advantageous because it tends to be minimally invasive yet it provides valuable diagnostic information. However, this test does not determine characteristics of peripheral …

Design, Characterization And Application Of A Multiple Input Stethoscope Apparatus, Spencer Geng Wong

Master's Theses

For this project, the design, implementation, characterization, calibration and possible applications of a multiple transducer stethoscope apparatus were investigated. The multi-transducer sensor array design consists of five standard stethoscope diaphragms mounted to a rigid frame for a-priori knowledge of their relative spatial locations in the x-y plane, with compliant z-direction positioning to ensure good contact and pressure against the subject’s skin for reliable acoustic coupling. When this apparatus is properly placed on the body, it can digitally capture the same important body sounds investigated with standard acoustic stethoscopes; especially heart sounds. Acoustic signal inputs from each diaphragm are converted to …

Joint Reaction Force And Contributions Of Surrounding Muscles To Knee Joint Load During Stair Ascent In Total Knee Replacement Patients And Healthy Individuals, Robert Jacob Rasnick

Masters Theses

Total knee replacement (TKR) is commonly used to correct end stage knee osteoarthritis (OA) of the knee joint. Unfortunately, difficulty with stair climbing has been seen to exist, prolonging the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future research. The outcome of a TKR is intended to reestablish normal motion and loading of the knee. Musculoskeletal modeling provides a means to accurately approximate joint loading and the corresponding muscle contributions during a movement.

The purpose of the present study was to examine …

Human Metaphase Chromosome Analysis Using Image Processing, Akila M.S Subasinghe Arachchige

Electronic Thesis and Dissertation Repository

Development of an effective human metaphase chromosome analysis algorithm can optimize expert time usage by increasing the efficiency of many clinical diagnosis processes. Although many methods exist in the literature, they are only applicable for limited morphological variations and are specific to the staining method used during cell preparation. They are also highly influenced by irregular chromosome boundaries as well as the presence of artifacts such as premature sister chromatid separation.

Therefore an algorithm is proposed in this research which can operate with any morphological variation of the chromosome across images from multiple staining methods. The proposed algorithm is capable …