Biomedical Engineering and Bioengineering Commons^™

Fatigue Strength Of Common Tibial Intramedullary Nail Distal Locking Screws, Lanny V. Griffin, Robert M. Harris, Joseph J. Zubak

Biomedical Engineering

Premature failure of either the nail and/or locking screws with unstable fracture patterns may lead to angulation, shortening, malunion, and IM nail migration. Up to thirty percent of all unreamed nail locking screws can break after initial weight bearing is allowed at 8–10 weeks if union has not occurred. The primary problem this presents is hardware removal during revision surgery. The purposes of our study was to evaluate the relative fatigue resistance of distal locking screws and bolts from representative manufacturers of tibial IM nail systems, and develop a relative risk assessment of screws and materials used. Evaluations included quantitative …

Botulinum Toxin For Non-Surgical Lateral Release In Subjects With Patellofemoral Pain, Laura Maple

Theses and Dissertations

Previous studies for treating Patellofemoral Pain Syndrome (PFPS) are controversial regarding the effectiveness in alleviating anterior knee pain (AKP). The muscular imbalance between the vastus medialis oblique/vastus lateralis (VMO/VL) may be the underlying mechanical issue causing PFPS. It is hypothesized that Botox can decrease the force production capability of the lateral musculature mechanically similar to surgery. Strengthening the VMO while using Botox treatment can alleviating the muscular imbalance that occurs with subjects with PFPS. A double blind study, having all participants blinded and uninformed of the injection contents, was implemented to test this hypothesis testing three female subjects. Four knees …

Applied Electrokinetics For Tissue Engineering Applications, Stephanie R. Tully-Dartez

Doctoral Dissertations

Tissue engineering could provide an alternative source of transplant tissue regardless of donor supply and with reduced risk of immune rejection. Engineered tissue requires three critical components for successful development: the cells, growth factors, and the scaffold on which they will initially grow. The scaffold acts as a temporary extracellular matrix (ECM) allowing cell attachment and acclimation to the environment prior to synthesis and construction of the cell's native ECM. Prior to cell seeding, the scaffold must be characterized to determine whether or not the pore geometry is conducive to cell implantation. Electrochemical impedance spectroscopy (EIS) provides a unique and …

Nano-Formulation And Controlled Delivery Of Low Solubility Anticancer Drugs, Anshul Agarwal

Doctoral Dissertations

Optimal drug delivery and reduction of systemic adverse effects have been age old problems in chemotherapeutics in all types of human cancer. During chemotherapy, using water insoluble drugs like paclitaxel and tamoxifen, it has been realized that better formulations are needed for more specific and controlled drug delivery of these agents. In a novel approach to form high content stable nanocolloids of these drugs with controllable release rate, a sonicated layer-by-layer (LbL) polyelectrolyte coating technology is suggested. The desired features of pharmaceutical carriers for intravenous administration include their small size and biodegradability, good loading capacity for a given drug, high …

A Real-Time, 3-D Musculoskeletal Model For Dynamic Simulation Of Arm Movements, Edward K. Chadwick, Dimitra Blana, Antonie J. Van Den Bogert, Robert F. Kirsch

Mechanical Engineering Faculty Publications

Neuroprostheses can be used to restore movement of the upper limb in individuals with high-level spinal cord injury. Development and evaluation of command and control schemes for such devices typically require real-time, ldquopatient-in-the-looprdquo experimentation. A real-time, 3-D, musculoskeletal model of the upper limb has been developed for use in a simulation environment to allow such testing to be carried out noninvasively. The model provides real-time feedback of human arm dynamics that can be displayed to the user in a virtual reality environment. The model has a 3-DOF glenohumeral joint as well as elbow flexion/extension and pronation/supination and contains 22 muscles …

Gold Nanorod-Mediated Photothermolysis Induces Apoptosis Of Macrophages Via Damage Of Mitochondria, Ling Tong, Ji-Xin Cheng

Other Nanotechnology Publications

Aims: Induction of apoptosis or necrosis in activated macrophages by gold nanorod-mediated photothermolysis is demonstrated and the mechanisms underlying the processes are investigated. Materials & methods: Gold nanorods were functionalized with cysteine-octaarginine peptides (R8-NRs). Uptake of R8-NRs by activated macrophages was monitored by two-photon luminescence imaging. The laser irradiation conditions were controlled to induce apoptosis or necrosis to R8-NR-internalized macrophages. Mitochondrial damage and reactive oxygen species overproduction during photothermolysis was investigated by confocal fluorescence microscopy and transmission-electron microscopy. Results: Activated macrophages efficiently uptake R8-NRs both in vitro and in live animals. Laser irradiation of internalized nanorods with controlled power density …

The In Vitro Characterization Of Chitosan-Plga Nanoparticle/Plasmid Dna Complexes, Hali Bordelon

Honors Capstones

No abstract provided.

Ankle Load Modulates Hip Kinetics And Emg During Human Locomotion, Keith E. Gordon, Ming Wu, Jennifer H. Kahn, Yasin Y. Dhaher, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

The purpose of this research was to examine the role of isolated ankle-foot load in regulating locomotor patterns in humans with and without spinal cord injury (SCI). We used a powered ankle-foot orthosis to unilaterally load the ankle and foot during robotically assisted airstepping. The load perturbation consisted of an applied dorsiflexion torque designed to stimulate physiological load sensors originating from the ankle plantar flexor muscles and pressure receptors on the sole of the foot. We hypothesized that 1) the response to load would be phase specific with enhanced ipsilateral extensor muscle activity and joint torque occurring when unilateral …

Analysis Of Electroencephalogram Signals For The Identification Of Mental Tasks, My Thy Thi Tran

Electrical & Computer Engineering Theses & Dissertations

Electroencephalogram (EEG) signals can be used for implicit communication such as to control robots or medical equipment by brain activity or to detect an individual's intentions of committing premeditated crimes. An EEG based brain-computer interface allows paralyzed patients to express their thoughts. However, biological and technical artifacts heavily interfered with EEG signals due to blinking of the eyes, muscle activities and line noise. Sometimes the noise interference due to signal artifacts becomes more prominent than the information content. This thesis investigates novel feature extraction methodologies in EEG signals to represent different thought processes and employs neural network-based pattern classification techniques …

In Vitro Ovarian Tumor Growth And Treatment Response Dynamics Visualized With Time-Lapse Oct Imaging, Conor L. Evans, Imran Rizvi, Tayyaba Hasan, Johannes F. De Boer

Dartmouth Scholarship

In vitro three-dimensional models for metastatic ovarian cancer have been useful for recapitulating the human disease. These spheroidal tumor cultures, however, can grow in excess of 1 mm in diameter, which are difficult to visualize without suitable imaging technology.Optical coherence tomography (OCT) is an ideal live imaging method for non-perturbatively visualizing these complex systems. OCT enabled detailed observations of the model at both nodular and cellular levels, revealing growth dynamics not previously observed. The development of a time-lapse OCT system, capable of automated, multidimensional acquisition, further provided insights into the growth and chemotherapeutic response of ovarian cancer.

The Rom / Uwo Mummy Project: A Microcosm Of Progress In Mummy Research, Andrew J. Nelson, R. Chhem, I. A. Cunningham, S. N. Friedman, G. Garvin, G. Gibson, P. V. Granton, David W. Holdsworth, S. Holowka, F. Longstaffe, V. Lywood, N. Nguyen, R. Shaw, M. Trumpour, Andrew D. Wade, C. D. White

Anthropology Presentations

The beginnings of the Royal Ontario Museum can be traced back to the excavations and collections of Charles Trick Currelly, a staff member of the Egyptian Exploration Fund in the early 1900s. Currelly excavated with Sir Flinders Petrie at Abydos and with Edouard Naville at Deir el Bahari. With the assistance of Robert Mond and others, Currelly amassed a rich and diverse collection that became the basis for the ROM, which opened its doors in 1914. Part of that collection included several Egyptian mummies (Currelly 1971) .

The Egyptologicalholdings at the ROM include eight mummies: one dating to the Predynastic …

The Relationships Between Muscle, External, Internal And Joint Mechanical Work During Normal Walking, Kotaro Sasaki, Richard R. Neptune, Steven A. Kautz

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Muscle mechanical work is an important biomechanical quantity in human movement analyses and has been estimated using different quantities including external, internal and joint work. The goal of this study was to investigate the relationships between these traditionally used estimates of mechanical work in human walking and to assess whether they can be used as accurate estimates of musculotendon and/or muscle fiber work. A muscle-actuated forward dynamics walking simulation was generated to quantify each of the mechanical work measures. Total joint work (i.e. the time integral of absolute joint power over a full gait cycle) was found to underestimate total …

Assessing The Prediction Potential Of An In Silico Computer Model Of Intracranial Pressure Dynamics, Wayne Wakeland, Rachel Agbeko, Kevin Vinecore, Mark Peters, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

Objective: Traumatic brain injury (TBI) frequently results in poor outcome, suggesting that new approaches are needed. We hypothesized that a patient-specific in silico computer model of intracranial pressure (ICP) dynamics may predict the ICP response to therapy.

Design: In silico model analysis of prospectively collected data.

Setting: Twenty-three and 16-bed pediatric intensive care units in two tertiary care academic hospitals.

Patients: Nine subjects with severe TBI undergoing ICP monitoring (7 M/2 F, age range 3-17 years).

Interventions: Random changes in head-of-bed (HOB) (0[degrees], 10[degrees], 20[degrees], 30[degrees], 40[degrees]) elevation and respiratory rate (to achieve a [DELTA]ETco2 = +/-3-4 mm Hg) were …

Biofilm Inhibitory Coatings Formulated From Glass Polyalkenoate Cement Chemistry: An Evaluation Of Their Adhesive Nature, A. Coughlan, D. Boyd, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Researchers evaluated the adhesive nature of the biofilm inhibitory coatings formulated from glass polyalkenoate cement (GPC) chemistry with the aim to establish the novel testing modality by modifying the conventional T-peel tests. Special consideration was given to determine the resistance of a bonded assembly of two adherents having at least one adherent flexible to quantify the bond between tape and a surgical metal substrate bonded by a luting GPC. The delaminated tape surface was examined by scanning electron microscopy (SEM) with an accelerating voltage of 20 K V to determine whether failure of the bond was adhesive of cohesive in …

Synthesis And Characterization Of Hazelnut Oil-Based Biodiesel, Yixiang Xu, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The demand for diesel fuel far exceeds the current and future biodiesel production capabilities of the vegetable oil and animal fat industries. New oilseed crops that do not compete with traditional food crop are needed to meet existing energy demands. Hybrid hazelnut oil is just such an attractive raw material for production of biodiesel. Hazelnut oil was extracted from hybrid hazelnuts and the crude oil was refined. Hazelnut oil-based biodiesel was prepared via the transesterification of the refined hazelnut oil with excess methanol using an alkaline catalyst. The effects of reaction temperature, time and catalyst concentration on the yield of …

Simulated Scatter Performance Of An Inverse-Geometry Dedicated Breast Ct System, Reema Bhagtani, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

The purpose of this work was to quantify the effects of scatter for inverse-geometry dedicated breast CT compared to cone-beam breast CT through simulations. The inverse geometry was previously proposed as an alternative to cone-beam acquisition for volumetric CT. The inverse geometry consists of a large-area scanned-source opposite a detector array that is smaller in the transverse direction. While the gantry rotates, the x-ray beam is rapidly sequenced through an array of positions, acquiring a truncated projection image at each position. Inverse-geometry CT (IGCT) is expected to detect less scatter than cone-beam methods because only a fraction of the object …

Short-Term Osteoclastic Activity Induced By Locally High Concentrations Of Recombinant Human Bone Morphogenetic Protein–2 In A Cancellous Bone Environment, Jeffrey M. Toth, Scott D. Boden, J. Kenneth Burkus, Jeffrey Badura, Steve M. Peckham, William Mckay

Biomedical Engineering Faculty Research and Publications

Study Design. An experimental study investigating osteoclastic activity induced by rhBMP-2 in sheep.

Objective. To examine the effects of increasing local rhBMP-2 concentration on osteoclastic response and peri-implant bone resorption.

Summary of Background Data. Level I clinical studies have established the safe and effective volume and concentration of rhBMP-2 delivered on an absorbable collagen sponge. However, peri-implant bone resorption appearing as decreased mineral density has been observed radiographically in rare instances after implantation of rhBMP-2 on an absorbable collagen sponge (rhBMP-2/ACS).

Methods. Bilateral corticocancellous defects were created in the distal femora of 30 adult sheep. Combinations of rhBMP-2/ACS implant volume …

Position Concordant - Haptic Mouse, Ravi Rastogi

Theses and Dissertations

Haptic mice, computer mice modified to have a tactile display, have been developed to enable access to computer graphics by individuals who are blind or visually impaired. Although these haptic mice are potentially very helpful and have been frequently used by the research community, there are some fundamental problems with the mouse, limiting its acceptance. In this paper we have identified the problems and have suggested solutions using one haptic mouse, the VT Player. We found that our modified VT Player showed significant improvement both in terms of the odds of obtaining a correct responses and the time to perform …

Imaging Radiation Pneumonitis In A Rat Model Of A Radiological Terrorism Incident, Robert C. Molthen, Qingping Wu, Gary S. Krenz, Meetha Medhora, Elizabeth R. Jacobs, John E. Moulder

Biomedical Engineering Faculty Research and Publications

We have developed a rat model of single, sub-lethal thoracic irradiation. Our irradiation protocol is considered representative of exposures near the detonation site of a dirty bomb or small nuclear device. The model is being used to investigate techniques for identifying, triaging and treating possible victims. In addition to physiological markers of right ventricular hypertrophy, pulmonary vascular resistance, and arterial distensibility, we present two methods for quantifying microvascular density. We used methods including microfocal X-ray imaging to investigate changes in lung structure/function resulting from radiation exposure. Radiation pneumonitis is a complication in subjects receiving thoracic irradiation. A radiographic hallmark of …

Dual Parametric Sensors For Highly Sensitive Nucleic Acid Detection, Manu Sebastian Mannoor

Theses

The primary focus of this research work was on the design and development of a molecular scale (nano-scale) capacitive sensing mechanism for the highly sensitive and label-free detection of Nucleic Acid hybridization. These novel capacitive sensors with nano-scale electrode spacing offer solutions to many problems suffered by the conventional signal transduction mechanisms, thereby immensely improving the sensitivity of the biomolecular detection processes. Reducing the separation between the capacitive electrodes to the same scale as the Debye length of the sample solution, results in the overlapping of the electrical double layers of the two electrodes, thereby confining them to occupy a …

Evaluation Of Medical Alarm Sounds, Elizbha Philip

Theses

Auditory alarms in medical equipments perform considerably below their optimal level. Concern has been expressed about the quality of medical alarms by a large number of researchers in recent years. A detailed literature survey on the medical alarm related problems has been carried out. Hospital visits were made to obtain real life information and data of alarm sounds in various type of monitors used in OR and ICU. A laboratory experiment has been conducted on selected melodic alarm sounds. These melodic alarm sounds are being implemented in medical equipments and the idea of design is proposed in ISO / IEC …

Aptamer-Based Nano-Scale Dielectric Sensor For Protein Detection, Teena James

Theses

The specific detection and precise quantification of protein molecules play an essential role in basic discovery research as well as in clinical practice. In this research work, a novel protein detection mechanism based on nanoscale dielectric sensor functionalized with aptamer probes is developed. This work has been done in collaboration with Rational Affinity Devices LLC. The use of aptamer based detection offers several advantages over the traditional labor intensive antibody based immunosensing. In the initial phase of the work, the binding affinities of rationally designed oligomers towards a specific protein molecule (IgG) was studied and optimized under varying conditions of …

Deciphering The Biology Of Axon Stretch-Growth, Joseph R. Loverde

Theses

Traditional nerve regeneration strategies focus on growth cone-mediated growth, a form of nerve growth that occurs primarily during embryogenesis. Early axons continue to grow from the end distal to the soma, seeking targets on which to synapse. It is believed that once the axons synapse, stretch-growth takes over and is responsible for the great lengths achieved by nerves of the central and peripheral nervous systems. Recent work has demonstrated stretch-growth in vitro resulting in dramatically increased growth rates compared to the growth cone. Here, the aim was to decipher the underlying biology associated with axon stretch-growth using two approaches. First, …

Study And Development Of Ultrasound Monitoring Of Skeletal Defects, Kavil Patel

Theses

Fatigue fractures are fine disruptions of normal bone architecture whose identification is often unreliable or difficult using x-rays (Robinson, Wilson et al.; Kundel 2004; Swischuk and Hernandez 2004). A fatigue fracture results from the application of abnormal loads to a bone with normal elastic resistance and is associated with new or different activity, and strenuous or repeated activity. The feasibility of using ultrasound to detect and monitor fatigue fractures and other structural damage in bone was established in this study.

The use of Low Transient Pulse (LTP) technology to drive the ultrasound transducers proved to enhance detection resolution and quality …

Finger Walking Control Of A Two-Dimensional Walking Model Through Inverse Kinematics, Jordan Ratcliff

Theses

Those people who have spinal cord injuries (SCI) must remain in wheelchairs due to disruption of the neural signaling to their muscles. Functional electrical stimulation (FES) has proved itself to be an option for restoring some motion and some walking for the patient. Electrodes can either be placed on the skin or muscle to provide an electrical impulse that stimulates the muscles into contraction. Current systems provide buttons that use set functions for left and right steps with constant direction and size. It is desired however that the user be allowed a more natural and variable control method of controlling …

Assessing Trainer Hand Forces For Manual Body Weight Supported Walking, Manish Raval

Theses

Spinal cord injuries occur in approximately 12,000 to 15,000 people per year in the U.S. About 10,000 of these people are permanently paralyzed. Most spinal cord traumas occur in young, healthy individuals. Males between 15 and 35 years old are most commonly affected.

Recently new approaches to facilitate walking recovery for individuals after a spinal cord injury, have been directed towards a therapy known as Locomotor Training (LT) that implements repetitive stepping on a treadmill using body weight support. A major intent of LT research is to investigate the effect of an extended period of LT on bilateral muscle activation …

Comparing Stent Design Using Computational Fluid Dynamics To Predict Wall Shear Stress Based Parameters, Jonathan Murphy, Fergal Boyle

Conference Papers

No abstract provided.

Rapid-Response Urban Cfd Simulations Using A Gpu Computing Paradigm On Desktop Supercomputers, Inanc Senocak, Julien C. Thibault, Matthew Caylor

Mechanical and Biomedical Engineering Faculty Publications and Presentations

In the event of chemical or biological (CB) agent attacks or accidents, first-responders need hazard prediction data to launch effective emergency response action. Accurate and timely knowledge of the wind fields in urban areas is critically important to identify and project the extent of CB agent dispersion to determine the hazard-zone. In their 2008 report (GAO-08-180), U.S. Government Accountability Office has reported that first responders are limited in their ability to detect and model hazardous releases in urban environments. The current set of modeling tools for contaminant dispersion in urban environments rely on empirical assumptions with diagnostic equations (Wang et …

Can We Engineer Our Way To Good Health?, Russell T. Carr

The University Dialogue

No abstract provided.

Preparation And Characterization Of Protein-Nanotube Conjugates, Jonathan S. Dordick, Dhiral A. Shah, Ravindra C. Pangule, Shyam Sundhar Bale, Prashanth Asuri, Amit Joshi, Akhilesh Banerjee, David Vance, Ravi S. Kane

Bioengineering

This chapter describes methods of immobilizing proteins on carbon nanotubes, using two different routes—physical adsorption and covalent attachment. We also provide an overview on how such conjugates can be characterized with the help of various techniques, such as Raman, Fourier transform infrared (FT-IR), circular dichroism (CD), and fluorescence spectroscopies, in addition to the standard enzyme kinetic analyses of activity and stability. Both the attachment routes—covalent and noncovalent—could be used to prepare protein conjugates that retained a significant fraction of their native structure and function; furthermore, the protein conjugates were operationally stable, reusable, and functional even under harsh denaturing conditions. These …