Biomedical Engineering and Bioengineering Commons^™

Quantification Of Functional Near Infrared Spectroscopy To Assess Cortical Reorganization In Children With Cerebral Palsy, Fenghua Tian, Mauricio R. Delgado, Bilal Khan, Sameer C. Dhamne, George Alexandrakis, Mario I. Romero, Linsley Smith, Dahlia Reid, Hanli Liu, Nancy J. Clegg

Bioengineering Faculty Publications - Archive

No abstract provided.

Importance Of Phase Unwrapping For The Reconstruction Of Microwave Tomographic Images, Tomasz M. Grzegorczyk, Paul M. Meaney, Soon Ik Jeon, Shireen D. Geimer, Keith D. Paulsen

Dartmouth Scholarship

Microwave image reconstruction is typically based on a regularized least-square minimization of either the complex-valued field difference between recorded and modeled data or the logarithmic transformation of these field differences. Prior work has shown anecdotally that the latter outperforms the former in limited surveys of simulated and experimental phantom results. In this paper, we provide a theoretical explanation of these empirical findings by developing closed form solutions for the fie

The Conversion Of Low-Grade Heat Into Power Using Supercritical Rankine Cycles, Huijuan Chen

USF Tampa Graduate Theses and Dissertations

Low-grade heat sources, here defined as below 300 ºC, are abundantly available as industrial waste heat, solar thermal, and geothermal, to name a few. However, they are under-exploited for conversion to power because of the low efficiency of conversion. The utilization of low-grade heat is advantageous for many reasons. Technologies that allow the efficient conversion of low-grade heat into mechanical or electrical power are very important to develop.

This work investigates the potential of supercritical Rankine cycles in the conversion of low-grade heat into power. The performance of supercritical Rankine cycles is studied using ChemCAD linked with customized excel macros …

Time Dependent Fixation And Implantation Forces For A Femoral Knee Component: An In Vitro Study, Travis A. Burgers, Jim Mason, Matthew Squire, Heidi-Lynn Ploeg

Mechanical Engineering Faculty Publications

Implant survival rate is a primary concern for individuals receiving a primary total knee arthroplasty. Loosening is the primary reason for revision surgery and was therefore the focus of the current study. To better understand the mechanics of implant fixation, the time-dependent fixation of a femoral knee component was measured in vitro on three cadaveric femurs. The fixation of each femoral knee component was measured with strain gauged implants for at least 10 minutes on each femoral component. Additionally, impaction forces were measured during the implantation of each component. These forces were 2–6 times less than previously reported. The implantation …

Development Of A Physical Windkessel Module To Re-Create In Vivo Vascular Flow Impedance For In Vitro Experiments, Ethan Kung, Charles A. Taylor

Publications

To create and characterize a physical Windkessel module that can provide realistic and predictable vascular impedances for in vitro flow experiments used for computational fluid dynamics validation, and other investigations of the cardiovascular system and medical devices. We developed practical design and manufacturing methods for constructing flow resistance and capacitance units. Using these units we assembled a Windkessel impedance module and defined its corresponding analytical model incorporating an inductance to account for fluid momentum. We tested various resistance units and Windkessel modules using a flow system, and compared experimental measurements to analytical predictions of pressure, flow, and impedance. The resistance …

Personal Navigation Via High-Resolution Gait-Corrected Inertial Measurement Units, Özkan Bebek, Michael A. Suster, Srihari Rajgopal, Michael J. Fu, Xuemei Huang, M. Cenk Çavu¸So˘Glu,, Darrin J. Young, Mehran Mehregany, Antonie J. Van Den Bogert, Carlos H. Mastrangelo

Mechanical Engineering Faculty Publications

In this paper, a personal micronavigation system that uses high-resolution gait-corrected inertial measurement units is presented. The goal of this paper is to develop a navigation system that uses secondary inertial variables, such as velocity, to enable long-term precise navigation in the absence of Global Positioning System (GPS) and beacon signals. In this scheme, measured zerovelocity duration from the ground reaction sensors is used to reset the accumulated integration errors from accelerometers and gyroscopes in position calculation. With the described system, an average position error of 4 m is achieved at the end of half-hour walks.

Distribution Of Capillary Transit Times In Isolated Lungs Of Oxygen-Tolerant Rats, Madhavi Ramakrishna, Zhuohui Gan, Anne V. Clough, Robert C. Molthen, David L. Roerig, Said H. Audi

Biomedical Engineering Faculty Research and Publications

Rats pre-exposed to 85% O₂ for 5–7 days tolerate the otherwise lethal effects of 100% O₂. The objective was to evaluate the effect of rat exposure to 85% O₂ for 7 days on lung capillary mean transit time (t¯c) and distribution of capillary transit times (h _c(t)). This information is important for subsequent evaluation of the effect of this hyperoxia model on the redox metabolic functions of the pulmonary capillary endothelium. The venous concentration vs. time outflow curves of fluorescein isothiocyanate labeled dextran (FITC-dex), an intravascular indicator, and coenzyme Q₁ hydroquinone …

Removal Of Low Density Sediments By Vegetative Filters, Brent M. Hall

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

The use of vegetative filter strips (VFS) is a longstanding best management practice for the removal of sediment and other pollutants from overland flow. Many attempts have been made to model the effectiveness of a VFS based upon soil, vegetation, and sediment properties, and also upon flow conditions, but little work has been done to investigate the reliability of the existing models when considering sediments, such as microbial pathogens, that have a lower density than the mineral sediments used for development of the models. The objectives of this study were to: 1) quantify the ability of a VFS to remove …

Can Spr Be Used To Interrogate The Double Layer Of Nacl, Brandon Kawula

Biomedical Engineering

Solutions of reagent grade salt .1, .01, .001, .0001, .00001M were run through a SPR to see if SPR had enough resolution to detect the formation of the electric double layer. We found that NaCl did in fact return a detectable signal. The signal shape seems to depend on concentration. While more study may need to be done to get definite information it looks like SPR can interrogate the double layer.

Production Of Anatomical Models From Ct Scan Data, John Brennan

Other resources

Rapid Prototyping (RP) technology was conceived in the mid 1980s as a method of manufacturing models, particularly to support the design of new motor vehicles. However as early as 1995 the potential to take data from medical scanners and generate models of patient anatomy to assist clinicians plan complex surgical procedures had been recognised, albeit by researchers rather than the mainstream medical industry. Over the last 15 years the production of preoperative planning models has increased dramatically and moreover, the potential to produce customised implants recognised.

Although RP technology is now established in the medical field work is still on …

Plasma Mediated Molecular Delivery, Richard J. Connolly

USF Tampa Graduate Theses and Dissertations

Non-viral delivery of plasmid DNA has traditionally relied upon physical forces applied directly to target tissues. These physical methods typically involve contact between an applicator and the target tissue and often cause transient patient discomfort. To overcome the contact-dependent limitations of such delivery methodologies, an atmospheric direct current plasma source was developed to deposit ionized gas molecules onto localized treatment sites. The deposition of charged species onto a treatment site can lead to the establishment of an electric field with strengths similar to those used for traditional electroporation. In vitro experiments proved that this technology could transiently permeabilize cell membranes …

Individual Muscle Contributions To The Axial Knee Joint Contact Force During Normal Walking, Kotaro Sasaki, Richard R. Neptune

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Muscles are significant contributors to the high joint forces developed in the knee during human walking. Not only do muscles contribute to the knee joint forces by acting to compress the joint, but they also develop joint forces indirectly through their contributions to the ground reaction forces via dynamic coupling. Thus, muscles can have significant contributions to forces at joints they do not span. However, few studies have investigated how the major lower-limb muscles contribute to the knee joint contact forces during walking. The goal of this study was to use a muscle-actuated forward dynamics simulation of walking to identify …

Deletion Of The Cel48s Cellulase From Clostridium Thermocellum, Daniel G. Olson, Shital A. Tripathi, Richard J. Giannone, Jonathan Lo, Nicky C. Caiazza, David A. Hogsett, Robert L. Hettich, Adam M. Guss, Genia Dubrovsky, Lee R. Lynd

Dartmouth Scholarship

Clostridium thermocellum is a thermophilic anaerobic bacterium that rapidly solubilizes cellulose with the aid of a multienzyme cellulosome complex. Creation of knockout mutants for Cel48S (also known as CelS, S(S), and S8), the most abundant cellulosome subunit, was undertaken to gain insight into its role in enzymatic and microbial cellulose solubilization. Cultures of the Cel48S deletion mutant (S mutant) were able to completely solubilize 10 g/L crystalline cellulose. The cellulose hydrolysis rate of the S mutant strain was 60% lower than the parent strain, with the S mutant strain also exhibiting a 40% reduction in cell yield. The cellulosome produced …

The Virtual Hip: An Anatomically Accurate Finite Element Model Based On The Visible Human Dataset, Jonathan M. Ford

USF Tampa Graduate Theses and Dissertations

The purpose of this study is to determine if element decimation of a 3-D anatomical model affects the results of Finite Element Analysis (FEA). FEA has been increasingly applied to the biological and medical sciences. In order for an anatomical model to successfully run in FEA, the 3-D model’s complex geometry must be simplified, resulting in a loss of anatomical detail. The process of decimation reduces the number of elements within the structure and creates a simpler approximation of the model. Using the National Library of Medicine’s Visible Human Male dataset, a virtual 3-D representation of several structures of the …

Surface Morphology Of Platelet Adhesion Influenced By Activators, Inhibitors And Shear Stress, Melanie Groan Watson

Doctoral Dissertations

Platelet activation involves multiple events, one of which is the generation and release of nitric oxide (NO), a platelet aggregation inhibitor. Platelets simultaneously send and receive various agents that promote a positive and negative feedback control system during hemostasis. Although the purpose of platelet-derived NO is not fully understood, NO is known to inhibit platelet recruitment. NO's relatively large diffusion coefficient allows it to diffuse more rapidly than platelet agonists. It may thus be able to inhibit recruitment of platelets near the periphery of a growing thrombus before agonists have substantially accumulated in those regions.

Results from two studies in …

An Analytical Model For Rotator Cuff Repairs, A. Aurora, Jorge E. Gatica, A.J. Van Den Bogert, J. A. Mccarron, Kathleen A. Derwin

Chemical & Biomedical Engineering Faculty Publications

Background: Currently, natural and synthetic scaffolds are being explored as augmentation devices for rotator cuff repair. When used in this manner, these devices are believed to offer some degree of load sharing; however, no studies have quantified this effect. Furthermore, the manner in which loads on an augmented rotator cuff repair are distributed among the various components of the repair is not known, nor is the relative biomechanical importance of each component. The objectives of this study are to (1) develop quasi-static analytical models of simplified rotator cuff repairs, (2) validate the models, and (3) predict the degree of …

Classification Of Emg Signals To Control A Prosthetic Hand Using Time-Frequesncy Representations And Support Vector Machines, Juan Manuel Fontana

Doctoral Dissertations

Myoelectric signals (MES) are viable control signals for externally-powered prosthetic devices. They may improve both the functionality and the cosmetic appearance of these devices. Conventional controllers, based on the signal's amplitude features in the control strategy, lack a large number of controllable states because signals from independent muscles are required for each degree of freedom (DoF) of the device. Myoelectric pattern recognition systems can overcome this problem by discriminating different residual muscle movements instead of contraction levels of individual muscles. However, the lack of long-term robustness in these systems and the design of counter-intuitive control/command interfaces have resulted in low …

Nonlinear Control Strategy For A Cost Effective Myoelectric Prosthetic Hand, Cristian Federico Pasluosta

Doctoral Dissertations

The loss of a limb tremendously impacts the life of the affected individual. In the past decades, researchers have been developing artificial limbs that may return some of the missing functions and cosmetics. However, the development of dexterous mechanisms capable of mimicking the function of the human hand is a complex venture. Even though myoelectric prostheses have advanced, several issues remain to be solved before an artificial limb may be comparable to its human counterpart. Moreover, the high cost of advanced limbs prevents their widespread use among the low-income population.

This dissertation presents a strategy for the low-level of control …

Alterations In Multiple Measures Of White Matter Integrity In Normal Women At High Risk For Alzheimer's Disease, Brian T. Gold, David K. Powell, Anders H. Andersen, Charles D. Smith

Neuroscience Faculty Publications

There is evidence that disruption of white matter (WM) microstructure is an early event in the course of Alzheimer's disease (AD). However, the neurobiological bases of WM microstructural declines in presymptomatic AD are unknown. In the present study we address this issue using a multimodal imaging approach to the study of presymptomatic AD. Participants were 37 high-risk (both family history of dementia and one or more APOE4 alleles) women and 20 low-risk (neither family history nor APOE4) women. Groups were matched for age, education, neuropsychological performance, and vascular factors that could affect white matter. Whole-brain analyses of diffusion tensor imaging …

Detrimental Thoracoabdominal Interaction With Lateral Airbag Restraints, Jason John Hallman

Dissertations (1934 -)

Side impact motor vehicle crashes pose unique challenges for occupant protection, particularly with regard to torso injury mitigation. The minimal crush distance between the vehicle exterior and the occupant torso has necessitated advanced passive safety technologies in response to tightened regulatory requirements and increased public awareness of safety issues. In particular, lateral airbag restraints (side airbags) have undergone a rapid and unregulated introduction in recent years, with US availability increasing to over 90% of new vehicles in 2010. As with frontal airbag restraints, the prdissertationsity for injury to occupants in close proximity to side airbag deployment remains a concern. Test …

The Effect Of Ionic Dissolution Products Of Ca-Sr-Na-Zn-Si Bioactive Glass On In Vitro Cytocompatibility, S. Murphy, A. W. Wren, Mark R. Towler, D. Boyd

Chemical and Biochemical Engineering Faculty Research & Creative Works

Many commercial bone grafts cannot regenerate healthy bone in place of diseased bone. Bioactive glasses have received much attention in this regard due to the ability of their ionic dissolution products to promote cell proliferation, cell differentiation and activate gene expression. Through the incorporation of certain ions, bioactive glasses can become therapeutic for specific pathological situations. Calcium-strontium-sodium-zinc-silicate glass bone grafts have been shown to release therapeutic levels of zinc and strontium, however the in vitro compatibility of these materials is yet to be reported. In this study, the in vitro cytocompatibility of three different calcium-strontium-sodium-zinc-silicate glasses was examined as a …

Development Of A Unique Whole-Brain Model For Upper Extremity Neuroprosthetic Control, Dominic Nathan

Dissertations (1934 -)

Neuroprostheses are at the forefront of upper extremity function restoration. However, contemporary controllers of these neuroprostheses do not adequately address the natural brain strategies related to planning, execution and mediation of upper extremity movements. These lead to restrictions in providing complete and lasting restoration of function. This dissertation develops a novel whole-brain model of neuronal activation with the goal of providing a robust platform for an improved upper extremity neuroprosthetic controller. Experiments (N=36 total) used goal-oriented upper extremity movements with real-world objects in an MRI scanner while measuring brain activation during functional magnetic resonance imaging (fMRI). The resulting data was …

Selective Biochlorination Of Hydroxyquinolines By A Flavin-Dependent Halogenase, Fuchao Xu, Amanda Merkley, Dayu Yu, Jixun Zhan

Biological Engineering Faculty Publications

Rdc2 is a flavin-dependent halogenase from Pochonia chlamydosporia. Through the introduction of a His₆-tag to both the N- and C-termini, the isolation yield of Rdc2 from Escherichia coli using Ni-NTA affinity chromatography was increased by three-fold. In vitro reaction of Rdc2 and a flavin reductase (Fre) with seven different hydroxyquinolines revealed that 3-hydroxyquinoline (3), 5-hydroxyquinoline (5), 6-hydroxyquinoline (6), and 7-hydroxyquinoline (7) can be specifically halogenated. These products were prepared by incubating the corresponding substrates with IPTG-induced E. coli BL21(DE3)/Rdc2. They were respectively characterized as 3-hydroxy-4-chloroquinoline (3a), 5-hydroxy-6-chloroquinoline (5a), 5-chloro-6-hydroxyquinoline (6a), and 7-hydroxy-8-chloroquinoline (7a) by NMR and MS …

Comparison Of Antibacterial Properties Of Commercial Bone Cements And Fillers With A Zinc-Based Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Postoperative infection following invasive surgical procedures is a significant cause for concern, particularly in spinal reconstructive surgery. The objective of this study is to compare the antibacterial efficacy of a novel zinc-based glass polyalkenoate cement (Zn-GPC) based on 0.04SrO-0.12CaO-0.36ZnO- 0.48SiO₂ glass, to a number of commercially available bone cements and fillers including Simplex P + Tobramycin (S_Tob), Spineplex (S_pine) and Novabone Putty (N_Put). The agar diffusion test was performed on each material against Escherichia coli, Staphlococcus epidermidis, Pseudomonas aeruginosa and Staphlococcus Aureus. S_Tob was found to produce large inhibition zones in each …

Ankle Strength And Functional Limitations In Children And Adolescents With Type I Osteogenesis Imperfecta, Angela Caudill, Ann Flanagan, Sahar Hassani, Adam Graf, Ruta Bajorunaite, Gerald F. Harris, Peter A. Smith

Biomedical Engineering Faculty Research and Publications

Purpose: To determine whether children with type I osteogenesis imperfecta (OI) exhibit ankle plantar flexor weakness and whether this correlates with physical function.

Methods: Twenty children and adolescents with type I OI and 20 age-matched controls (age 6-18 years) participated in a single evaluation session. Data included strength assessment, Gillette Functional Assessment Questionnaire, Pediatric Outcome Data Collection Instrument (PODCI), and Faces Pain Scale—Revised.

Results: Ankle plantar flexor weakness was evident in the OI group compared with the control group. Heel-rise strength correlated with ankle isometric plantar flexion strength. Limitations in PODCI subscales—sports and physical function and pain/comfort—are present in the …

Dispersion Of Cytotoxic Properties Of Multi-Walled Carbon Nanotubes Suspended In Biological Solutions With Tween 80: Their Role In Enhancing Killing Effects Of Nanosecond Pulse Electric Fields On Tumor Cell Lines, Bhargava S. Kalluri

Biological Sciences Theses & Dissertations

The objective of this study was to determine whether multi-walled carbon nanotubes (MWCNTs) suspended in the surfactant Tween 80 give an additive killing effect on tumor cells when exposed to nsPEFs. In this study, MWCNTs were suspended in DMEM and RPMI with or without T80 (surfactant). The size distribution of MWCNTs suspended in these solutions was evaluated with a Delsa™ Nano Zeta potential and sub micro particle Size Analyzer and confirmed with microscopy. The cytotoxicity of MWCNTs dispersed in different concentrations of T80 was evaluated in PANC1 (Human pancreatic cancer cell line) and Jurkat cell lines (Human T-cell lymphoblast cell …

Fetal Breathing Movement And Its Distinctive Characteristics In Bio-Magnetic Data, Umit Deniz Ulusar

Theses and Dissertations

Magnetoencephalography (MEG) is widely used to study magnetic fields generated by the electrical activity of the human brain and can also be applied for fetal neurological health assessment. The fetal MEG (fMEG) signals are often contaminated with other bio-magnetic signals such as fetal breathing movement (FBM), which acts as an interfering factor for fetal neurological signals. This study was carried out to identify the bio-magnetic signals pertinent to the FBM. The fMEG signals were captured using superconducting quantum interference devices (SQUIDs) and the FBMs were recorded by an ultrasound-based video technique. The simultaneous recording is challenging since SQUIDs are extremely …

A Simple Apparatus For Measuring Cell Settling Velocity, Zhaowei Wang, Joanne M. Belovich

Chemical & Biomedical Engineering Faculty Publications

Accurate cell settling velocity determination is critical for perfusion culture using a gravity settler for cell retention. We have developed a simple apparatus (a 'settling column') for measuring settling velocity and have validated the procedure with 15-μm polystyrene particles with known physical properties. The measured settling velocity of the polystyrene particles is within 4% of the value obtained using the traditional Stokes' law approach. The settling velocities of three hybridoma cell lines were measured, resulting in up to twofold variation among cell lines, and the values decreased as the cell culture aged. The settling velocities of the nonviable cells were …

Modeling Of Micro-Diaphragm For Optical Pressure Sensor For Human Artery Pulse Wave Detection., Khairunnisa Hasikin

Student Works (2010-2019)

This thesis presents the development of a micro-diaphragm for an optical pulse pressure sensor using Micro-electro-mechanical Systems (MEMS) technology. Modelling of the micro-diaphragm was conducted and the comparison of its performance was simulated for silicon nitride and polyirnide materials. In addition. diaphragm's radius and thickness were varied to further analyze the performance of the micro-diaphragm. There are three design parameters that affecting the micro-diaphragm performance namely diaphragms radius. thickness and material. Thus, an optimization analysis using Taguchi method was done to attain significant design parameters that give the best micro-diaphragm performance. Findings indicated that the best performance of the micro-diaphragm …

Differential Regulation Of Immature Articular Cartilage Compressive Moduli And Poisson's Ratios By In Vitro Stimulation With Igf-1 And Tgf-Β1, Gregory M. Williams, Kristin J. Dills, Christian R. Flores, Michael E. Stender, Kevin M. Stewart, Lauren M. Nelson, Albert C. Chen, Koichi Masuda, Scott J. Hazelwood, Stephen M. Klisch, Robert L. Sah

Biomedical Engineering

Mechanisms of articular cartilage growth and maturation have been elucidated by studying composition-function dynamics during in vivo development and in vitro culture with stimuli such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-beta 1 (TGF-β1). This study tested the hypothesis that IGF-1 and TGF-β1 regulate immature cartilage compressive moduli and Poisson’s ratios in a manner consistent with known effects on tensile properties. Bovine calf articular cartilage from superficial-articular (S) and middle-growth (M) regions were analyzed fresh or following culture in medium with IGF-1 or TGF-β1. Mechanical properties in confined (CC) and unconfined (UCC) compression, cartilage matrix composition, and explant …