Master of Sciences (Engineering), Case Western Reserve University, 2018, Biomedical Engineering

Peripheral nerve injuries have traditionally been treated with a variety of different surgical procedures, but the use of allografts for these injuries remain to be a largely unexplored concept. As a result, there has yet to be a successful protocol created for imaging cells on the surface of nerve allografts. In this thesis, I developed a z-stack projection imaging protocol for nerve allografts and demonstrated the ability to take clear and focused images of cell retention and proliferation on the surface of the allograft. I also optimized the preparation of the nerve graft to improve cell and connective progenitor cell (CTP) retention rates.

Committee: George Muschler MD (Committee Chair); Eben Alsberg PhD (Advisor); Robert Kirsch PhD (Committee Member); Cynthia Boehm (Committee Member) Subjects: Biomedical Engineering; Cellular Biology; Optics

Doctor of Nursing Practice Degree Program in Population Health Leadership DNP, Xavier University, 2018, Nursing

The effects of sleep loss are a population health issue for the 65.7 million family caregivers in the United States (U.S.). Between 60-95% of caregivers report poor sleep quality because of sleep disruption. The purpose of this Doctorate of Nursing Practice (DNP) scholarly project was to evaluate the effectiveness of a combination of interventions, referred to as a sleep bundle, to improve sleep quality for caregivers of children with chronic conditions such as bone marrow transplant (BMT) using the FADE (Focus Analyze Develop Execute Evaluate) quality improvement (QI) methodology. It was hypothesized that the sleep bundle will decrease sleep disruption, and ultimately improve the sleep quality of primary caregivers of BMT patients. Specific aims to test the hypothesis included: (1) Compare sleep efficiency and quality in caregivers with and without the sleep bundle; (2) Identify and mitigate barriers and obstacles to implement the sleep bundle. Although the sleep bundle was followed reliably the nights of sleep bundle intervention phase; the sleep bundle was not found to be statistically significant in improving the sleep efficiency and sleep quality of caregivers of BMT patients. Additional evaluation of the sleep bundle and its impact on improving the sleep efficiency and quality of caregivers is needed with a larger sample size. Possible alteration of specifics interventions combined in the sleep bundle should also be explored.

Committee: Elizabeth Bragg PhD, RN (Committee Chair); Robin Saxon DNP, RN (Committee Co-Chair) Subjects: Health Care; Health Sciences; Medicine; Nursing; Psychology

Master of Science (M.S.), University of Dayton, 2017, Renewable and Clean Energy

Photovoltaic-thermal (PVT) technology is a relatively new technology that comprises a photovoltaic (PV) panel coupled with a thermal collector to convert solar radiation into electricity and thermal energy simultaneously. Since cell temperature affects the electrical performance of PV panels, coupling a thermal collector with a PV panel contributes to extracting the heat from the latter to improve its performance. In order to ensure a sufficient temperature difference between the PV cells and the working fluid temperature entering the thermal collector, the circulated water has to reject the heat that has been removed from the PV cells into a relatively colder environment. Borehole thermal energy storage (BTES), which is located underground, often serves as this relatively colder environment due to the stability of underground temperatures, which are usually lower than the working cell temperature. Use of BTES is especially beneficial in summer, when the degradation in cells efficiency is highest. In this thesis, the electrical, thermal, and economic performances of a PVT system are evaluated for three types of buildings -- residential, small office, and secondary school -- in two different climates in the United States, one of which is hot and the other is cold. For each case, two different scenarios are considered. In the first, a PVT system is coupled with BTES, and a ground-coupled heat pump (GCHP) is in use. In the second, a PVT system is coupled with BTES and no GCHP is in use. Each scenarios' GCHP performance is assessed as well. Both the PVT collectors and GCHP performances are evaluated over short and long-term to study the effect of continued ground heat imbalance on both technologies.

Committee: Andrew Chiasson Ph.D. (Committee Chair); Youssef Raffoul Ph.D. (Committee Member); Robert Gilbert Ph.D. (Committee Member) Subjects: Energy; Engineering; Mechanical Engineering

Doctor of Philosophy, University of Akron, 2023, Chemical Engineering

Wastewater stemming from both residential and industrial sources commonly contains notable quantities of ammonium (N) and phosphate (P). Elevated levels of N and P within wastewater can give rise to significant challenges for aquatic ecosystems and wildlife. Meanwhile, it is crucial to recognize that N and P are valuable resources with diverse applications. This dual role of N and P, both as potential environmental pollutants and indispensable resources, underscores the need for efficient and sustainable approaches to manage and recover these nutrients from wastewater. The initial facet of this study delves into the utilization of the redox flow deionization cell (RFDC) as a new alternative approach for the elimination of N and P from wastewater. RFDC boasts commendable attributes, including heightened energy efficiency, continuous operational capabilities, and concurrent deionization within the ion's removal channel, coupled with ion concentration within the concentrated channel. The investigation of RFDC performance was conducted, taking into consideration the influence of wastewater concentration and applied cell voltage. This encompassed an appraisal of parameters such as the average salt removal rate, ion removal efficiency, and electrical energy consumption, including both N and P removal experiments. Additionally, the impact of coexisting ions, namely sodium cations (Na+) and chloride anions (Cl-), on N and P removal efficacy was subject to examination. The findings of this study underscore the expeditious removal of N and P within the ion's removal channel, coinciding with the concurrent concentration of ions within the concentrated channel. Intriguingly, it emerges that N exhibits a heightened selectivity in contrast to the coexisting cation (Na+), while P exhibits considerably diminished selectivity when juxtaposed with the coexisting anion (Cl-). This observation manifests in augmented electrical energy consumption attributable to the concomitant rem (open full item for complete abstract)

Committee: Zhenmeng Peng (Advisor); Ping Yi (Committee Member); Qixin Zhou (Committee Member); Bi-min Zhang Newby (Committee Member); Lingxing Yao (Committee Member) Subjects: Chemical Engineering; Chemistry; Environmental Engineering; Sustainability

MS, University of Cincinnati, 2019, Engineering and Applied Science: Electrical Engineering

This work aims at demonstrating the concept of utilizing waste heat of Photovoltaic cell by thermoelectric devices. Experiments are performed to study the effect of variation of sun concentration from 0.25 to 1.8 suns (1 sun = 1000 W/m2) on the efficiency of the Photovoltaic cell having 5 cm x 5 cm dimensions. It is found that with the increase of sun intensity from 400 (x0.25) to 1600 W/m2 (x1.6) the photovoltaic cell shows variation of the power output from 0.10 W to 0.25 W. Also, this sun intensity variation resulted in the heating of photovoltaic cell. We measured the top and bottom surface temperatures of the photovoltaic cell. The top surface temperature varied in range from 304.7 K to 380.3 K with increasing solar intensity, while the bottom surface has a lower temperature compared to the top surface varying from 303.85 K to 370.55 K. Thermoelectric devices are attached to the bottom surface of the photovoltaic cell to recover the waste heat from the photovoltaic cell. In order to demonstrate the thermoelectric principle, we have first measured the power output we could fetch through the K type thermocouple junction; the same TC junction we have used to measure the temperature on the bottom surface of photovoltaic cell. At input sun intensity of 1800 W/m2 we have measured the maximum power output of around 0.28 µW from this single thermocouple junction. Finally, a V- type longitudinal thermoelectric device made of multiple TE legs is fabricated and attached at the back surface of the photovoltaic cell to demonstrate the increase of the power output. We have also discussed how increasing in the thermal contact area of the thermocouple device could help in increasing the power output from the PV cell. Also, in this work we have performed full three-dimensional numerical simulation on the hybrid photovoltaic and transverse thermoelectric device with natural air convection using ANSYS to gauge the power generation performance for future research.

Committee: Je-Hyeong Bahk Ph.D. (Committee Chair); Marc Cahay Ph.D. (Committee Member); Peter Kosel Ph.D. (Committee Member) Subjects: Engineering

Master of Science, The Ohio State University, 2017, Food, Agricultural and Biological Engineering

A Microbial Fuel Cell (MFC) is a device used to harvest electrons from living microorganisms to generate electrical power. After decades of development, new architectures have been developed and new materials have been applied to MFC systems. Improvements to this promising technology have been extensively reported. However, scientists and engineers are still facing difficulties on enhancing energy output and increasing the MFC system efficiencies. In addition to physical resistances caused by MFC materials, there are still many unknown factors affecting the electron transfer pathway used by microorganisms in MFC environments. To increase the performance, a series of technologies have been integrated into MFCs. For instance, MFC technology has been combined with other technologies such as algae pounds, anaerobic digesters and constructed wetlands, to increase substrate utilization efficiency. As one example, CW-MFCs have already been studied for wastewater treatment and electricity generation. However, the system efficiencies presented by current models are low, and new designs need be explored to reduce the energy cost during installation and operation of CW-MFC systems. The first objective of this thesis research was to review the development of MFCs and relevant technologies, then to evaluate the energy loses and efficiencies in MFC systems, leading to a comprehensive understanding of MFC system from a thermodynamic viewpoint. The second objective was to design and construct a down-flow Constructed Wetland-Microbial Fuel Cell combined system with a semi-air cathode and analyze its performance. This innovative design will be able to enhance the system efficiencies of CW-MFCs by reducing external energy requirements, and this research will provide foundational work for further CW-MFC explorations

Committee: Ann Christy (Advisor); Olli Tuovinen (Committee Member); Lingying Zhao (Advisor) Subjects: Agricultural Engineering