BS, Kent State University, 2019, College of Education, Health and Human Services / School of Health Sciences

Caffeine consumption prior to resistance exercise has demonstrated significant increases in maximal strength in resistance-trained individuals, along with concomitant increases in heart rate (HR) and blood pressure (BP). Therefore, the purpose of the present study was to examine the effects of caffeine (4mg/kg) alone or in conjunction with acute resistance exercise in resistance-trained women on resistance exercise performance and cardiovascular hemodynamics. The acute bout of resistance exercise consisted of two sets of 10 repetitions at 75% 1 repetition maximum (1RM) for the squat and bench press, and one set to failure at 70% 1RM for both resistance exercises. Performance variables included the total load lifted, as well as the number of repetitions completed. Hemodynamic variables included HR, systolic and diastolic BP, mean arterial pressure, and pulse pressure. Measurements were taken at rest (Rest1), 45 minutes after consumption of the caffeine or placebo (Rest2), immediately post exercise (Rec1), and 10-minutes post exercise (Rec2). Paired samples t-tests were used to evaluate differences in total load, and the total number of repetitions performed during set 3. A 2 x 4 repeated measures ANOVA was used to assess the effects of condition (caffeine vs placebo) across the time (Rest1, Rest2, Rec1, Rec2) with a Bonferroni correction. Eight resistance-trained women (mean±SD: 23±3 yrs) completed the study. There were no significant differences between conditions for any performance variable. However, there was a significant (p=0.001) main effect of time for HR, such that it was elevated at Rec1 and Rec2, compared to Rest1 and Rest2. There were no significant interactions of main effects for systolic or diastolic BP. There was a significant interaction (p=0.04) for mean arterial pressure such that following caffeine consumption it was elevated at Rest2 compared to Rest1, and was different than Rest2 following the placebo. There was also no interaction or ma (open full item for complete abstract)

Committee: J. Derek Kingsley Ph.D. (Advisor) Subjects: Health Sciences

Master of Science in Exercise and Health Studies, Miami University, 2014, Exercise and Health Studies

The purposes of this investigation were to determine if proxies for muscle fiber composition and anthropometric measurements can predict systolic (SBP) and diastolic blood pressure (DBP), pulse pressure(PP), and mean arterial pressure (MAP). We studied 370 Division I Male and Female Athletes from various sports. Multiple regressions were run to predict blood pressure from anthropometric variables and proxies for fiber type. SBP included Neck circumference, Arm span, and MaxVi (.663;43.4%); DBP included BMI, Arm Length, and Neck Circumference (.298;8.9%); PP included peak force, height, MaxVi, and Neck Circumference (.639;40.2%); and MAP included BMI and Neck Circumference (.458;20.5%). Blood pressure exists on a normal curve, and because natural characteristics like fiber type and anthropometric-characteristics affect blood pressure, their influence on normal homeostatic blood pressure should be considered in the determination of pathology from normal physiology and the evaluation of treatment options.

Committee: Ron Cox PhD (Committee Chair); Mark Walsh PhD (Committee Member); Thelma Horn PhD (Committee Member) Subjects: Biomechanics; Kinesiology; Physiology

Master of Science, Miami University, 2024, Mechanical and Manufacturing Engineering

Wire electrical discharge machining (WEDM) enables production of complex parts with tight tolerances, although maintaining dimensional accuracy in corners and tapers remains challenging due to wire deflection and vibration. This study optimizes WEDM parameters for achieving high-accuracy in machining complex geometrical parts and taper cuts in 6061 Aluminum alloy using Excetek W350G WEDM machine with a copper wire electrode. Parameters including Wire Tension, Pulse On-Time, Pulse Off-Time, Wire Feed Rate, Open Circuit Voltage, and Flashing Pressure were varied using L18 Taguchi Orthogonal Array and response graph method to identify optimal cutting conditions. Results indicated feature-specific optimization is crucial, as different geometrical features (rectangular fins, triangular fins, gears) exhibited varying critical parameters. Key findings highlighted the importance of Wire Tension and Pulse On-Time in maintaining cutting accuracy, although at varying levels for specific features. Response graphs demonstrated effects of major WEDM parameters on corner and profile accuracies, whereas Taguchi analysis provided optimum settings of parameters for each feature and taper cutting. Validation experiments for rectangular fins showed significant improvement in the dimensional error for the fin length and taper angle. These advancements will enhance precision, efficiency, and versatility of WEDM processes in machining complex profiles, and corners, contributing to precision manufacturing.

Committee: Muhammad Jahan (Advisor); Carter Hamilton (Committee Member); Jinjuan She (Committee Member) Subjects: Aerospace Engineering; Biomedical Engineering; Industrial Engineering; Mechanical Engineering

Master of Science (M.S.), University of Dayton, 2022, Aerospace Engineering

Rotating Detonation Engines (RDEs) and pressure gain combustion (PGC) present a pathway to increased performance and fuel savings due to improved thermal efficiency and power density. RDEs utilize detonations to combust reactants, which provides higher thermal efficiencies than deflagration combustion. This increase in efficiency comes from increases in total pressure achieved across the detonation front, whereas deflagrations produce losses in total pressure. However, high thermal loads have limited uncooled and conventionally manufactured RDE test duration. Currently there is a need to develop novel cooling schemes that minimize the associated performance penalty, provide adequate cooling to extend test duration, and characterize changes in RDE performance and operability. This investigation was aimed at quantifying film cooling when applied to the unsteady and adverse pressure gradient of a RDE. Two film cooled outer-body combustion liners were manufactured and tested using a H2-air operated 6-inch RDE with an aerospike plug nozzle, heat sink center-body, and a 0.64 inch detonation channel width. Additionally, a control liner without holes was manufactured and tested. The two film cooled liners varied film pressure drop to characterize changes in RDE operability, temperature response, and cooling manifold pressure unsteadiness. All liners used approximately equivalent total flow area, as well as diameter weighted axial and circumferential spacing to allow comparison. The combustion air injection area ratio was set to 0.33, and the nozzle area ratio set to 1.0 and 0.66 relative to the channel area. Combustion air manifold pressures, cooling air manifold pressures, cooling air temperature, combustion liner temperature, operating mode, detonation stability, and detonation wave speed were analyzed for an array of combustion air mass flow rates, equivalence ratios, cooling air mass flow rates, and liner geometries. A high-speed camera was utilized to confirm operating (open full item for complete abstract)

Committee: Matthew Fotia (Committee Chair); Frederick Schauer (Committee Member); Adam Holley (Committee Member) Subjects: Aerospace Engineering; Mechanical Engineering

Doctor of Philosophy, Case Western Reserve University, 2016, Epidemiology and Biostatistics

This is a study to evaluate cross-sectional and longitudinal genetic associations among Metabolic Syndrome (MetS) risk factors and a select set of candidate genes involved in inflammatory, vasoconstrictive, and coagulation processes at the vascular epithelium in the Women's Interagency HIV Study (WIHS) Cohort. We conducted a candidate gene association analysis of multiple clinical measures for each component trait of MetS in a group of HIV-positive and -negative women of the WIHS. Thirty-two candidate genes were selected based on their pro-inflammatory, pro-vasoconstrictive, and pro-coagulative functions and expression in the vascular endothelium. The association was modeled with mixed effects model with both random slope and random intercepts. We have identified genetic variants in CKD14 and NFKB1 with longitudinal effects on MetS risk factors in African Americans and Hispanics. We provide evidence that the genetic architecture of MetS includes genes previously implicated in inflammation (NFKB1) and vessel repair (CDK14) and that HIV may mediate the magnitude of the some genetic associations.

Committee: Xiaofeng Zhu Ph.D. (Committee Chair); Robert Elston Ph.D. (Committee Member); Nathan Morris Ph.D. (Committee Member); Nora Nock Ph.D. (Committee Member); Barbara Gripshover M.D. (Committee Member); Bradely Aoiuzerat Ph.D. (Committee Member) Subjects: Epidemiology; Genetics

Doctor of Philosophy, University of Akron, 2014, Mechanical Engineering

The response of single-curvature composite panels under external blast was studied. For the single-curvature composite shells under external pressure pulse loading, Lagrange’s equations of motion were established to determine the shell response and the Budiansky-Roth criterion was used to examine the instability. The predicted transient shell response compared very well with FEA results from ABAQUS Implicit, and the predicted buckling loads also agreed with experiments on steel arches. Under various load durations, buckling was impulsive, dynamic and quasi-dynamic. Thicker composite shells were more likely to fail by first-ply failure rather than buckling. It was shown that the composite lay-up could be adjusted to increase the buckling resistance of the shell. For the single-curvature composite sandwich panels under external pressure pulse loading, a multi-layered approach was used to distinguish facesheets and core deformations. Core compressibility and transverse shear through the thickness were accounted for using linear displacement fields through the thickness. Equations of motion for the facesheet transient deformations were again derived from Lagrange’s equations of motion, and predicted solutions using this approach compared very well with FEA results from ABAQUS Implicit. In the case of core undergoing elastic deformations only, both facesheet fracture during stable deformation response and local dynamic pulse buckling of facesheets were considered as possible modes of failure in the curved sandwich panel. It was found that local facesheets buckling is more likely to occur than facesheet fracture in thin and deeply curved sandwich panels. The facesheet laminate lay-up could also be adjusted to improve the local buckling resistance of the curved sandwich panel. In the case of the core undergoing elastic-plastic deformations, a parametric study showed that blast resistance of the curved sandwich panel can be increased by allowing cores to un (open full item for complete abstract)

Committee: Michelle Hoo Fatt Dr. (Advisor); Xiaosheng Gao Dr. (Committee Member); Gregory Morscher Dr. (Committee Member); Ernian Pan Dr. (Committee Member); Kevin Kreider Dr. (Committee Member) Subjects: Mechanical Engineering

MS, University of Cincinnati, 2012, Medicine: Clinical and Translational Research

Background: In normotensive subjects, an exaggerated blood pressure response to exercise is associated with the development of resting hypertension. We sought to 1) determine the prevalence of elevated blood pressures during exercise in post-operative coarctation patients with normal resting blood pressure and 2) investigate associations with exercise induced hypertension in this population. Method: 38 subjects status post end to end anastomosis repair and resting normotension were prospectively enrolled. All patients underwent anthropometric and blood pressure measurements, echocardiographic evaluation of function, arterial stiffness assessment by pulse wave velocity and a graded exercise test. An abnormal response was defined as a maximum systolic blood pressure greater than the 95th percentile of published normal values. Correlation analyses and stepwise regression analyses were performed. Results: Mean age was 12.7 years, 79% male. Mean resting systolic blood pressure was 111.3 mmHg, mean exercise systolic blood pressure was 178.1 mmHg. The prevalence of a systolic blood pressure greater than the 95th percentile was 16.7%. In multivariate analysis, exercise systolic blood pressure index was associated with body mass index, age, aortic valve annulus, shortening fraction and pulse wave velocity (R2 = 0.79, p = 0.0009). Estimates of ventricular filling and indexed left ventricular mass were elevated. Conclusions: There is a risk of elevated systolic blood pressure during exercise in normotensive patients after coarctation repair. Resting blood pressures are useful but not sufficient. Echocardiography demonstrated abnormalities suggestive of a chronic cardiac burden despite resting normotension. Regular imaging may be necessary to improve long term outcomes. New paradigms for the continued follow-up of these patients are necessary.

Committee: Erin Nicole Haynes PhD (Committee Chair); Phillip Khoury MS (Committee Member); Thomas Kimball MD (Committee Member) Subjects: Surgery

Master of Science in Engineering, University of Akron, 2011, Civil Engineering

An analytical solution was derived for obtaining the large amplitude, damped response of a crushable foam core sandwich beam subjected to pressure pulse loading. The simply-supported sandwich beam, comprised of aluminum facesheets and a PVC foam core, was analyzed for its response to a uniformly distributed pressure pulse load. The equations of motion for the sandwich beam were developed considering first-order shear deformation and membrane stretching. The initial response of the beam was elastic until the onset of plasticity, when transverse shear stresses in the foam core exceeded the transverse shear yield strength of the foam. The facesheets remained elastic, while the core was elastic-plastic, throughout the entire load – unload cycle. Analytical results were compared to results from finite element analysis using ABAQUS Explicit and good agreement was found between them. The analytical solution can be used to design sandwich beam experiments for extracting foam damping properties.

Committee: Michelle Hoo Fatt Dr. (Advisor); Craig Menzemer Dr. (Committee Member) Subjects: Engineering; Materials Science; Mechanical Engineering

Master of Science in Engineering, University of Akron, 2006, Biomedical Engineering

Remote Physiological Monitoring as an application of telemedicine holds great promise for providing efficient and economical health care. Most telemedicine applications have been limited to the use of interactive video for physician consultations, educational, research and administrative purposes. In this research project, an attempt was made to design and implement software that provided an interactive remote physiological monitoring system with instantaneous feedback to the physician at any remote location, about the general health of the patient, through the internet. The software acquired sixteen channels of raw physiological signals and provided twenty parameters, which included heart rate, blood pressure, temperature and respiratory rate, describing the physiological condition of the patient. Reliable algorithms were implemented for the processing of raw physiological signals to provide accurate values of useful physiological parameters. The remote communication between the physician end and the patient end was achieved using the Transmission Control Protocol/Internet Protocol (TCP/IP). The data acquisition, signal processing and display of the processed output at patient's site were controlled by the physician at the remote site. The design of software was such that, it was interchangeably used for patient monitoring as well as training of subjects to control their physiological responses to various environmental stressors. The software was designed and implemented in the Microsoft Visual Basic 6.0® Integrated Development Environment.

Committee: Bruce Taylor (Advisor) Subjects:

Master of Science in Engineering, University of Akron, 2006, Biomedical Engineering

The measurement of blood pressure is a vital tool for any healthcare provider, purveying information that could help diagnose any number of pathologies. This is especially the case in critical care settings where the ability to continuously measure arterial blood pressure impacts immediate medical decisions. Of the techniques for noninvasive blood pressure measurement, cuff auscultation is clinically most often utilized. Unfortunately, this method requires a minimum rest period of one minute. Since this time lapse is unacceptable in a critical care setting, the need arises for a continuous and noninvasive method for blood pressure measurement. Several such commercially available methods exist, but they are often limited in clinical usefulness. It was the purpose of this study to investigate one such method involving the calculation of pulse transit time. This research was focused on: using both artificial simulations and previously measured simultaneous physiological electrocardiograph (ECG), photoplethysmograph (PPG), and continuous tonometric blood pressure data; applying the algorithm described by Fung to calculate arterial blood pressures from pulse transit time, and investigating an improvement to this algorithm; applying several digital differentiation techniques (spectral, central difference, original Pan-Tompkins, and Pan-Tompkins errata differentiation) for both ECG R-spike detection (compared to ECG R-spike detection without differentiation) and PPG landmark detection; and determining if statistically significant differences existed between the mean arterial pressures (MAP) obtained by various methodologies applied to several PPG curves, and between the beat-to-beat blood pressure measurements made by tonometry. Additionally this research investigated both mathematical and statistical differences that existed when each of the digital differentiators were applied to Fourier reconstructed idealized ECG and PPG waveforms. The primary conclusions drawn from th (open full item for complete abstract)

Committee: Dale Mugler (Advisor); Bruce Taylor (Advisor) Subjects: