Engineering Commons^™

Signal Processing Techniques For Artifact Removal In Electroencephalogram (Eeg), Jyoti Bhat

Bioengineering Theses - Archive

The electroencephalographic recordings measure the electric impulses generated in the brain, in response to a given stimulus. The spontaneous EEG data is used for diagnosis and treatment of some brain diseases. For the data to be used for clinical applications, it needs to be free of the various artifacts like the eye blinks, movement, head movements and muscle activity. These artifacts need to be corrected or the affected parts need to be removed in the preprocessing of the EEG dataset. This pre-processing is normally done manually, which tends to be not only time-consuming but also subjective. With large number of …

Diffuse Optical Imaging Of Brain Function Under Repetitive Transcranial Magnetic Stimulation And In Children With Cerebral Palsy, Sameer C. Dhamne

Bioengineering Theses - Archive

Diffuse Optical Imaging (DOI) is a non-invasive neuroimaging technique which measures the changes in oxy- and deoxy-hemoglobin concentrations at a high temporal resolution based on the principle of Near-Infrared Spectroscopy.DOI was combined with repetitive Transcranial Magnetic Stimulation (rTMS) to assess the neuronal changes induced in the cortical regions, which are directly under rTMS and the connected areas, by applying 1Hz rTMS to the left hemisphere of the motor cortex followed by the stimulation to the prefrontal cortex for two visits. The DOI signals were simultaneously acquired from both ipsilateral and contralateral brain regions before, during, and after rTMS. We observed …

Electrical Apparoaches For Selective Detection Of Cancer Biomarker Proteins With Aptamers, Priyanka Pachampettai Ramachandran

Bioengineering Theses - Archive

Cancer is a disease that is the central focus of many a researcher's attention. As it is a disease that can spread very rapidly and can be fatal in many cases, its early detection and early treatment can dramatically change mortality. Towards the early detection of the disease, antibodies are most commonly used for the detection of cancer biomarkers. The use of antibodies in diagnostics has proven fruitful in the past. But advancements in molecular biology have introduced aptamers for diagnostic and therapeutic purposes. Aptamers are oligonucleotides or peptides that are usually synthesized by a selective process called SELEX. Aptamers …

Biaxial Investigation Of Periosteal Mechanics, Olumide O. Aruwajoye

Bioengineering Theses - Archive

Limb lengthening procedures are used commonly to correct limb length discrepancies. Current methods in limb lengthening require a distraction of 1 mm per day using an external fixation device. Although the underlying mechanisms of new bone growth have been studied and discussed extensively, they remain not fully understood. It is thought, however, that mechanoreceptor cells of the periosteum play an important role. In an attempt to understand the contribution of periosteum, the biaxial mechanical properties of the periosteum are studied. Freshly excised porcine periosteum was used to investigate the effects of preload on the material symmetry, and the effects of …

Analysis Of Oxygen Uptake During Blood Flow Through A Rectangular Microchannel: A Two Phase Eulerian Model With Oxygen-Hemoglobin Reaction, Jamie Wright

Bioengineering Theses - Archive

The evolution of oxygenator design has culminated in the current strategy of utilizing micro-porous membranes to separate blood and oxygen phases while utilizing extra-luminal blood flow orientations to promote passive and active secondary mixing of the blood to inhibit the build up of concentration boundary layers near oxygen transfer surfaces that impede efficiency. Advances in fabrication techniques could allow for the manufacturing of oxygenators employing microchannels to decrease the diffusion path between oxygen and the red blood cells, more closely mimicking the strategy employed by the body. Because blood is actually a complex suspension, it is difficult to model. Furthermore, …

Understanding The Development Of Infant Feeding: A Spectral Analysis Approach, Pooja Vijaygopal

University of Kentucky Master's Theses

Feeding problems in preterm neonates stem from complications of early delivery. Attainment of independent feeding is a prerequisite for Neonatal Intensive Care Unit (NICU) discharges. Some quantitative studies of infant feeding involve excessive amounts of time for data processing. Multivariate spectral analysis was used to minimize time for investigation of variability in these rhythms. Auto and Cross-spectral parameters of the rhythms were correlated with Gestational Age (GA), Postmenstrual Age (PMA), Birthweight (BW), Days of Life (DOL), and Time Since First Nipple feeding (TSFN). Auto-spectral analysis showed 25.55% increase in Bandwidth of suck (bw-su) for a 2-week increase in GA (DOL …

Abnormal Collateral Artery Vasoactivity Following Chronic Ischemia, Trevor Cardinal, Thomas J. Kesler, Matthew D. Yocum

Biomedical Engineering

No abstract provided.

A Numerical Approach To Determine The Impact Of Network Remodeling On Blood Flow, Trevor Cardinal, Shilpi Ghosh, Stephanie A. Wood, Gabriel Gruionu

Biomedical Engineering

No abstract provided.

Alterations In Femoral Strain Following Hip Resurfacing And Total Hip Replacement, C. R. Deuel, A. A. Jamali, S. M. Stover, S J. Hazelwood

Biomedical Engineering

Bone surface strains were measured in cadaver femora during loading prior to and after resurfacing of the hip and total hip replacement using an uncemented, tapered femoral component. In vitro loading simulated the single-leg stance phase during walking. Strains were measured on the medial and the lateral sides of the proximal aspect and the middiaphysis of the femur. Bone surface strains following femoral resurfacing were similar to those in the native femur, except for proximal shear strains, which were significantly less than those in the native femur. Proximomedial strains following total hip replacement were significantly less than those in the …

Preliminary Investigation Of Novel Bone Graft Substitutes Based On Strontium-Calcium-Zinc-Silicate Glasses, D. Boyd, G. Carroll, Mark R. Towler, C. Freeman, P. Farthing, I. M. Brook

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone graft procedures typically require surgeons to harvest bone from a second site on a given patient (Autograft) before repairing a bone defect. However, this results in increased surgical time, excessive blood loss and a significant increase in pain. In this context a synthetic bone graft with excellent histocompatibility, built in antibacterial efficacy and the ability to regenerate healthy tissue in place of diseased tissue would be a significant step forward relative to current state of the art philosophies. We developed a range of calcium-strontium-zinc-silicate glass-based bone grafts and characterized their structure and physical properties, then evaluated their in vitro …

Optimizing Computer-Aided Colonic Polyp Detection For Ct Colonography By Evolving The Pareto Front, Jiang Li, Adam Huang, Jack Tao, Jiamin Liu, Robert L. Van Uitert, Nicholas Petrick, Ronald Summers

Electrical & Computer Engineering Faculty Publications

A multiobjective genetic algorithm is designed to optimize a computer-aided detection (CAD) system for identifying colonic polyps. Colonic polyps appear as elliptical protrusions on the inner surface of the colon. Curvature-based features for colonic polyp detection have proved to be successful in several CT colonography (CTC) CAD systems. Our CTC CAD program uses a sequential classifier to form initial polyp detections on the colon surface. The classifier utilizes a set of thresholds on curvature-based features to cluster suspicious colon surface regions into polyp candidates. The thresholds were previously chosen experimentally by using feature histograms. The chosen thresholds were effective for …

Biomedical Technology: Supporting Movement, Petros Katsioloudis

STEMPS Faculty Publications

According to the National Institute on Disability and Rehabilitation Research, an estimated 8.5 million children 21 years and younger have a disability (Jans & Stoddard, 1999). After about a decade, with the development of new and sophisticated materials (aluminum alloys, titanium alloys, and carbon fibers) and the integration of electronics, it was then possible to significantly improve the performance of prostheses, built with the so-called endo skeletal (or skeletal-modular) method (Mora, Beratni & Pedrotti, 2006).

Capillary Perfusion Kinematics In Lungs Of Oxygen-Tolerant Rats, Madhavi Ramakrishna

Master's Theses (2009 -)

Motivation:

Prolonged exposure to oxygen at high concentrations (hyperoxia), a common treatment for hypoxemia, is toxic to the lungs. Rats exposed to 85% O₂ for 5-7 days develop tolerance to the otherwise lethal effects of 100% O₂. Elucidating the factors that contribute to this tolerance could further our understanding of the mechanisms of lung O₂ toxicity. Since vascular remodeling involving loss of capillary volume and endothelial surface area has been reported in lungs from rats exposed to 85% O₂ for 7 days, we were interested in evaluating the effect of this hyperoxia model on lung …

Eeg During Pedaling: Brain Activity During A Locomotion-Like Task In Humans, Sanket G. Jain

Master's Theses (2009 -)

This study characterized the brain electrical activity during pedaling, a locomotor-like task, in humans. We postulated that phasic brain activity would be associated with active pedaling, consistent with a cortical role in locomotor tasks. 64 channels of electroencephalogram (EEG) and 10 channels of electromyogram (EMG) data were recorded from 10 neurologically-intact volunteers while they performed active and passive (no effort) pedaling on a custom-designed stationary bicycle. Ensemble average waveforms, two dimensional topographic maps and amplitude of the beta (13-35 Hz) frequency band were analyzed and compared between active and passive trials. The absolute amplitude (peak positive-peak negative) of the EEG …

Characterization Of The Electromagnetic Fields Inside A Wire Mesh Cage For Biotelemetry, Johnny Bernard Lienau

Master's Theses (2009 -)

A wire mesh cage composed of thin conductive wires will influence the behavior of electromagnetic fields within it. Theory suggests that the cage will behave like a low Q cavity. Many researchers have investigated electromagnetic field behavior in solid walled cavities and waveguides, but little of this work has probed into the effects of a wire mesh. Additionally, few studies have investigated RF communication in these types of environments. The primary goal of this work is to research wireless communication inside a low Q wire mesh cavity in the 200-700 MHz range. Through simulated and experimental results, ideal antenna locations …

Systems Identification Of Sensorimotor Control For Visually Guided Wrist Movements, Chintan Poladia

Master's Theses (2009 -)

The sensorimotor control system is a complicated system in which the neural controller uses the feedback information from sensory modalities (visual, proprioceptive, vestibular, auditory, etc.) to actuate the musculo-skeletal system in order to execute intended movements. It has been an ongoing research to decode this sensorimotor integration. The current study utilized a systems identification approach in conjunction with a one-degree-of-freedom robotic manipulandum to quantify (delays, noises, wrist dynamics and controller parameters) a simplified (linear time-invariant) model of sensorimotor control for visually guided wrist stabilization movements.

Four sensorimotor tasks were used to characterize the parameters of the sensorimotor control model. Open …

Cold Plasma Technology: Bactericidal Effects On Geobacillus Stearothermophilus And Bacillus Cereus Microorganisms, Angela D. Morris, Gayle B. Mccombs, Tamer Akan, Wayne L. Hynes, Mounir Laroussi, Susan L. Tolle

Dental Hygiene Faculty Publications

Introduction: Cold plasma, also known as Low Temperature Atmospheric Pressure Plasma (LTAPP) is a novel technology consisting of neutral and charged particles, including free radicals, which can be used to destroy or inactivate microorganisms. Research has been conducted regarding the effect of cold plasma on gram-positive bacteria; however, there is limited research regarding its ability to inactivate the spore-formers Geobacillus stearothermophilus and Bacillus cereus.

Purpose: The purpose of this study was to determine if cold plasma inactivates G. stearothermophilus and B. cereus vegetative cells and spores.

Methods: Nine hundred eighty-one samples were included in this study (762 experimental and …

Quantitative Prediction Of Body Surface Potentials From Myocardial Action Potentials Using A Summed Dipole Model, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This paper demonstrates quantitatively, using streamlined mathematics, how the transmembrane ionic currents in individual cardiac muscle cells act to produce the body surface potentials of the electrocardiogram (ECG). From fundamental principles of electrostatics, anatomy, and physiology, one can characterize the strength of apparent dipoles along a wavefront of depolarization in a local volume of myocardium. Net transmembrane flow of ionic current in actively depolarizing or repolarizing tissue induces extracellular current flow, which sets up a field of electrical potential that resembles that of a dipole. The local dipole strength depends upon the tissue cross section, the tissue resistivity, the resting …

Neonatal Cpr: Room At The Top—A Mathematical Study Of Optimal Chest Compression Frequency Versus Body Size, Charles F. Babbs, Andrew Meyer, Vinay Nadkarni

Weldon School of Biomedical Engineering Faculty Publications

Objective: To explore in detail the expected magnitude of systemic perfusion pressure during standard CPR as a function of compression frequency for different sized people from neonate to adult. Method: A 7-compartment mathematical model of the human cardiopulmonary system—upgraded to include inertance of blood columns in the aorta and vena cavae—was exercised with parameters scaled to reflect changes in body weight from 1 to 70 kg. Results: Maximal systemic perfusion pressure occurs at chest compression rates near 60, 120, 180, and 250 per minute for subjects weighing 70, 10, 3, and 1 kg, respectively. Such maxima are predicted by analytical …

Cellular Function Of The Ia-Motoneuron Circuit Following Peripheral Nerve Regeneration, Katie Leigh Bullinger

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Successful regeneration of a severed peripheral nerve is insufficient to restore the stretch reflex. This deficit occurs despite successful muscle reinnervation and functional restoration of the circuit components. For example, Ia afferents encode muscle stretch, Ia-motoneuron synapses reform to the extent of restoring low frequency transmission, and activation of motoneurons results in muscle force output. However, when recording intracellularly from reinnervated rat motoneurons during ramp hold and release muscle stretch, no excitatory synaptic potentials are detected in 2/3 motoneurons (Haftel et al., 2005), a clear sign that the synapses connecting Ia afferents with motoneurons are physiologically disrupted. This thesis examines …

Timing-Pulse Measurement And Detector Calibration Of The Osteoquant, Binu Eapen Enchakalody

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The OsteoQuant is a second-generation pQCT scanner, which can provide precisedensity assessment of bone. The scanner is being upgraded with an x-ray tube radiation source and a semiconductor CZT detector. This thesis provides solutions for two issues: motion-detector timing and dead-time/beam-hardening corrections. During translation, the motion-control system of the scanner repositions the source and detector by small intervals. However, the detector collects photon counts asynchronously with respect to the motor-timing pulses and reads photon counts (frames) at regular intervals based on its own clock. Since there needs to be correspondence between source/detector location and detector readout, the first part of …

Ion Transport Mechanisms During Hyposmotic Regulatory And Isosmotic Apoptotic Volume Decreases In A Human Lens Epithelial Cells Line, Ameet Ajit Chimote

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Living cells maintain constant volume in response to physiological stresses by altering trans-membrane ion, solute and water flow. In the present study, early and late membrane transport changes in human lens epithelial (HLE-B3) cells under hyposmotic and apoptotic stress were compared. Cell potassium (Ki), rubidium (Rbi)-uptake and water content were measured by atomic absorption spectrophotometry and gravimetry, respectively. Intracellular chloride concentration [Cl]i was determined with the fluorescence dye N- (ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE), during regulatory volume decrease (RVD) after hyposmotic stress and apoptotic volume decrease (AVD) induced by staurosporine (STP), a protein-kinase inhibitor. Cell water increased in hyposmotic balanced salt solution …

The In Vitro Interactions Between Tubulin And Hiv-1 Rev Require Rev's Multimerization And Arginine-Rich Motifs, Amit Sharma

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Rev is a 13 kDa regulatory HIV protein essential for viral replication. It trans-activates expression of late viral proteins by multimerizing onto target mRNA and promoting their export into the cytoplasm. During attempts to find the solution conditions needed to study Rev structure, Watts et al. (2000) discovered that Rev depolymerizes microtubules (MTs) in vitro through the formation of ringed tubulin intermediates called Rev-tubulin toroids (RTTs). Rev interactions with MTs are specific and are thought to mimic the mechanism of Kinesin-13 proteins, themselves potent MT depolymerases that regulate the assembly of the mitotic spindle. If Rev and Kinesin-13 proteins share …

Graphical User Interface (Gui) To Study Different Reconstruction Algorithms In Computed Tomography, Shital K. Abhange

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Computed tomography (CT) imaging relies on computational algorithms to reconstruct images from projections gathered from the CT scan. Depending on the scanner geometry, different types of reconstruction algorithms can be used. To study these different types of reconstruction algorithms in a user-friendly way, a software tool was built. The aim of the thesis was to provide a software platform to access a number of previously implemented reconstruction algorithms with ease and minimal knowledge of the reconstruction code. The goal was accomplished by building a Graphical User Interface (GUI) using MATLAB 7.7.0 (R2008b). In addition to creating mathematical objects and invoking …

Small Conductance Calcium-Activated Potassium (Sk) Channels In Mammalian Spinal Motoneurons, Zhihui Deng

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Three homologous small conductance calcium-activated potassium (SK) channel subunits (SK1, SK2, and SK3) are expressed in distinct and overlapping patterns in mammalian central nervous system. SK channels likely mediate the medium afterhyperpolarization (mAHP), which plays an essential role in regulating neuron repetitive firing frequency. In spinal motoneurons (MNs) the mAHP duration is shorter on average in fast (F-type) MNs than that in slow (S-type) MNs. To better understand the molecular basis for mAHP, we determined the expression and sub-cellular distribution of SK channels in normal, axonally-injured, and developing spinal MNs in vivo using immunohistochemistry and quantitative confocal imaging techniques.

SK2 …

Induction Of Socs-1 In Hsv-1-Infected Murine Keratinocytes: A Mechanism Of Inhibition Of Interferon Gamma, Kenneth Gene Frey

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Epidermal cells such as keratinocytes are the major site of Herpes Simplex Virus Type 1 (HSV-1) replication in active primary or recurring herpes infection. In this study, a murine keratinocyte cell line (HEL-30) was shown to be refractory to IFNγ induction of an antiviral state to HSV-1 infection, while IFNγ did induce an antiviral state in a murine fibroblast cell line (L929). Particularly, IFN-gamma and its peptide mimetic protected fibrobasts from viral-induced cytopathic effect while the keratinocytes were destroyed by the infection. Suppressor of cytokine synthesis-1 (SOCS-1) a negative regulator of IFNγ, was hypothesized to be responsible for the refractiveness …

Embryonic And Postnatal Development Of The Neural Circuitry Involved In Motor Control, Valerie Cari Ann Siembab

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The development of locomotion is believed to result from the maturation of the spinal circuits controlling motor output, however little is known about its mechanisms. To shed some light into this process we studied the development of the synaptic connectivity of two spinal inhibitory interneurons. Adult motoneurons are controlled by inhibitory networks that include recurrent and reciprocal inhibition (Pierrot-Deseilligny & Burke, 2005). Each is modulated by different ventral horn spinal interneurons that display synaptic connectivity adapted to their function: Renshaw cells (RCs) mediate recurrent inhibition, receive excitatory inputs from motor axons and inhibit homonymous and synergistic motoneurons; while Ia inhibitory …

Hif-1 Alpha: A Master Regulator Of Trophoblast Differentiation And Placental Development, Kashmira Kulkarni

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Early embryonic development occurs under low oxygen levels. The placenta is an organ transiently formed during pregnancy and plays a crucial role during development of the embryo. Alterations in the placental structure or function have been associated with the pathologies such as preeclampsia in humans. In mammals, the hypoxia inducible factor (HIF) transcription factors have been identified as the major regulators of cellular responses in low oxygen. In the current study, we investigated the effects of low oxygen on the differentiation of trophoblast stem cells, lineage committed trophoblast giant cells and labyrinthine lineage-committed cells. We examined the effects of an …

Central Mechanisms Regulating Pituitary-Adrenal Activity In Infant Guinea Pigs (Cavia Porcellus) During Exposure To Psychological Stressors: Independent And Combined Effects Of Maternal Separation And Novelty, Deborah Suzanne Maken

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Separation from the maternal attachment figure, particularly when it occurs in a novel or threatening environment, reliably increases pituitary-adrenal activity in a number of species, and is thought to increase later susceptibility to psychopathology in humans. However, little is known about the central mechanisms mediating these effects. Therefore, I investigated cortisol and ACTH levels in plasma, corticotropin-releasing factor (CRF) mRNA expression in the hypothalamic paraventricular nucleus (PVN), and c-Fos activity in a circuit [medial amygdala (MeA)- bed nucleus of the stria terminalus (BNST)] thought to drive pituitary-adrenal activity during exposure to psychological stressors, as well as in the PVN. Measurements …

Genetic Differentiation In Ambystomatid Salamanders Across A Fragmented Landscape, Joseph E. Bartoszek

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It is generally recognized that amphibian populations declining across the globe. Habitat loss is the primary cause of decline. The salamander family Ambystomatidae has experienced significantly more rapid decline than the average for amphibians. Coefficients of Conservatism (CoC) have been developed for amphibians in Ohio. These are based primarily on habitat requirements with high CoCs for amphibians with stringent habitat requirements (e.g. vernal pools associated with large, intact, undisturbed forest), and low CoCs for amphibians with less stringent habitat requirements. Genetic diversity in five species and one hybrid complex of ambystomatid salamander in southwest Ohio were examined and compared to …