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A Study On The Effects Of Cementless Total Knee Arthroscopy Implants' Surface Morphology With Finite Element Analysis, Peter Hunt Dec 2022

A Study On The Effects Of Cementless Total Knee Arthroscopy Implants' Surface Morphology With Finite Element Analysis, Peter Hunt

Master's Theses

Total knee arthroscopy is one of the most performed and most successful orthopedic surgeries, with nearly a million procedures performed in 2020 in the United States alone. Due to changing patient demographics, the use of cementless fixation for implant stability is becoming more prevalent amongst recipients. Cementless implants rely on the surface morphology of a porous coating to bond implant to bone; the quality of this bond is dependent on an interference fit and the roughness, or coefficient of friction, between implant and bone. Stress shielding is a comparison of the properties in implanted bone to natural bone; it is …


Biodegradation Of Methyl Tert-Butyl Ether And Tert-Butyl Alcohol Using Bioaugmentation With Biowish® Aqua, Elizabeth Villanueva Dec 2022

Biodegradation Of Methyl Tert-Butyl Ether And Tert-Butyl Alcohol Using Bioaugmentation With Biowish® Aqua, Elizabeth Villanueva

Master's Theses

Aqua, a commercial product manufactured by BiOWiSH® Technologies, was utilized in this research to study its effectiveness to biodegrade methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA). Microcosms containing varying concentrations of MTBE and TBA as well as a growth media and mineral salt solution were examined. Analytical instrumentation used in this study included the use of a gas chromatograph-mass spectrometer (GC/MS) to determine concentrations of MTBE and TBA and a spectrophotometer to extrapolate approximate active biomass concentrations in each experiment. Four different environmental conditions were tested for both MTBE and TBA. The environmental conditions tested for each contaminant included: …


Iot-Based Alert System For Geriatric, Vaibhav Meshram Dr, Meghana P V N, R Sahana, Sai Lakshmi Lasya V, Shreya S Reddy Dec 2022

Iot-Based Alert System For Geriatric, Vaibhav Meshram Dr, Meghana P V N, R Sahana, Sai Lakshmi Lasya V, Shreya S Reddy

Manipal Journal of Science and Technology

No abstract provided.


In Vitro Bioreactor For Mechanical Control And Characterization Of Tissue Constructs, Samuel Coeyman Dec 2022

In Vitro Bioreactor For Mechanical Control And Characterization Of Tissue Constructs, Samuel Coeyman

All Dissertations

Heart failure (HF) currently affects over 6 million Americans, 50% of whom die within 5 years of their initial diagnosis. A major contributor to the onset of HF is cardiac fibrosis in the myocardium, which arises when fibroblasts (FBs) are activated in response to heightened mechanical stress from overload conditions like hypertension. Activated FBs remodel the extracellular matrix (ECM) and secrete ECM proteins including collagen. FB remodeling has been studied in the past by applying forces and/or deformations to three-dimensional, cell-seeded gels and tissue constructs in vitro. Unfortunately, previous stretching platforms have traditionally not enabled mechanical property assessment to be …


The Rise Of Terrorism In Africa And What It Means For U.S. Policymakers, Bridget Mary Hughes Dec 2022

The Rise Of Terrorism In Africa And What It Means For U.S. Policymakers, Bridget Mary Hughes

Master's Theses

This thesis utilizes three case studies to measure the rise of terrorism in Africa. This qualitative data leads the reader to one ultimate question: what does the rise in terrorism in Africa mean for the United States (U.S.) and U.S. policymakers, National Security academia, students in National Security, if anything at all? The answer is: if civilian and military compounds are being targeted by these violent extremists, as these three case studies demonstrate, it is my recommendation that U.S. policymakers cease sending troops to the African theater and, instead, allocate funding to the citizens and nonprofits of the countries whom …


Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes Dec 2022

Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes

Legacy Theses & Dissertations (2009 - 2024)

Since its introduction, the amine-thiol cosolvent system has been successfully utilized for the deposition of various thin-film devices, but its mechanism of action is still uncertain. Herein, we have attempted to dissect some of the chemical characteristics of amine-thiol cosolvents, with a special interest taken towards a mixture of ethylenediamine (en) and mercaptoethanol (ME). Conductivity was measured for multiple amine-thiol combinations at different ratios to determine extent of ionization in solution, with en-ME having one of the highest solution conductivities. Exposing the solution to air for several days was found to decrease the conductivity of en-ME, indicating the formation of …


Improving Detection And Classification Of Steady-State Visual Evoked Potentials In Brain-Computer Interfaces, Hadi Habibzadeh Dec 2022

Improving Detection And Classification Of Steady-State Visual Evoked Potentials In Brain-Computer Interfaces, Hadi Habibzadeh

Legacy Theses & Dissertations (2009 - 2024)

Brain-computer interfaces (BCIs) provide an alternative communication channel to send computer commands without requiring any voluntary muscle control. They benefit people with limited communication capabilities due to motor function deficits, spinal cord injuries, and neurological disorders. They may also have applications for healthy individuals.


Development Of Nucleic Acid Diagnostics For Targeted And Non-Targeted Biosensing, Christopher William Smith Dec 2022

Development Of Nucleic Acid Diagnostics For Targeted And Non-Targeted Biosensing, Christopher William Smith

Legacy Theses & Dissertations (2009 - 2024)

The field of nucleic acid technology is rapidly expanding with new impactful discoveriesbeing made each year. Starting from the discovery of the double-helix structure, cloning, gene editing, polymerase chain reaction (PCR), CRISPR technology, and even the late mRNA vaccines; nucleic acid technology is at the forefront of improving medicine. Nucleic acid technology is extremely versatile due to its easy programmability, automated cheap synthesis, and even its catalog for numerous chemical modifications that can be used to alter structure stability. For example, the number of permutations that can be made with DNA just by altering the code for adenine (A), cytosine …


Building Structures From Mycelium, Noah M. Brown Dec 2022

Building Structures From Mycelium, Noah M. Brown

Physics

The purpose of this project was to develop a method for creating bricks from mycelium and agricultural waste. The bulk of the research happened in two parts, the first part being a period in which different substrates, strains, and methods were used build the bricks. This research took place in San Luis Obispo and was aided by a group of students in PSC392 under Dr. Pete Schwartz in early 2022. After developing a method for constructing these bricks, the research was moved to St. Thomas, Jamaica, in collaboration with an ecovillage called The Source Farm from July to September. The …


Optogenetic Heart Pacing And Heart Arrest In Drosophila Melanogaster Using Integrated Ocm Imaging And Light Stimulation System, Yuxuan Wang Dec 2022

Optogenetic Heart Pacing And Heart Arrest In Drosophila Melanogaster Using Integrated Ocm Imaging And Light Stimulation System, Yuxuan Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Optogenetics has been widely applied to cardiovascular research using different models. Among them, Drosophila melanogaster (fruit fly) outstands for its similarity of human genes for disease modeling and short life cycle for rapid screening to analyze genetic mechanisms of heart disease. However, most of the current models only allow either activation or inhibition of the heartbeat, which is not sufficient to model complex arrhythmia. Our lab developed a novel Drosophila transgenic model based on a double transgenic line containing two light-sensitive genes, Channelrhodopsin-2 (ChR2) and Halorhodopsin2.0 (NpHR2.0), that enable dual-directional control of the heartbeat rhythm. Real-time optical control of the …


Supporting Us Army Next-Generation Ground Vehicle Simulation Modeling Using An Integrated Ontology Suite, Edward Louis Dec 2022

Supporting Us Army Next-Generation Ground Vehicle Simulation Modeling Using An Integrated Ontology Suite, Edward Louis

All Theses

The development of the US Army’s next-generation of ground vehicle systems is supported by simulations that predict vehicle performance and inform engineering design choices in the design and acquisition process. In this paper, we describe the development of an Integrated Ontology Suite to support modeling and simulation of next generation military ground vehicles. The ontology suite is intended to address model reuse challenges and increase the shared understanding of ground vehicle system simulations. It is intended to function in a Model Library structure that stores, documents, assembles, and executes vehicle simulations. The ontology suite consists of four domain ontologies: Vehicle …


Utilizing Systematic Design And Shape Memory Alloys To Enhance Actuation Of Modular High-Frequency Origami Robots, Jessica M. Den Haese Dec 2022

Utilizing Systematic Design And Shape Memory Alloys To Enhance Actuation Of Modular High-Frequency Origami Robots, Jessica M. Den Haese

All Theses

Shape memory alloys (SMAs) describe a group of smart metallic materials that can be deformed by external magnetic, thermal, or mechanical influence and then returned to a predetermined shape through the cycling of temperature or stress. They have several advantages, such as having excellent mechanical properties, being low cost, and being easily manufactured, while also providing a compact size, completely silent operation, high work density, and requiring less maintenance over time. SMAs can undergo sold-to-solid phase transformations, and it is because of these phase transformations that they can experience shape memory effect (SME); or the ability to recover from a …


Using Reinforcement Learning To Improve Network Reliability Through Optimal Resource Allocation, Henley Wells Dec 2022

Using Reinforcement Learning To Improve Network Reliability Through Optimal Resource Allocation, Henley Wells

Graduate Theses and Dissertations

Networks provide a variety of critical services to society (e.g. power grid, telecommunication, water, transportation) but are prone to disruption. With this motivation, we study a sequential decision problem in which an initial network is improved over time (e.g., by adding or increasing the reliability of edges) and rewards are gained over time as a function of the network’s all-terminal reliability. The actions during each time period are limited due to availability of resources such as time, money, or labor. To solve this problem, we utilized a Deep Reinforcement Learning (DRL) approach implemented within OpenAI-Gym using Stable Baselines. A Proximal …


Development Of Optical Coherence Tomography Angiography System For Mouse Eye Imaging And Measurement Of Vasodilation, Yilin Li Dec 2022

Development Of Optical Coherence Tomography Angiography System For Mouse Eye Imaging And Measurement Of Vasodilation, Yilin Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Optical coherence tomography angiography (OCTA) is broadly known as a non-invasive technology that allows examining the retinal and choroidal vasculatures, alternative to fluorescein angiography. In this study, we have developed an optical coherence tomography (OCT) system for imaging the mouse eye. We measure the retinal thickness, which is 216.53um. We apply OCTA to characterize the quantitative change in vessel diameter and the perfusion density of the retina after the wild-type mice are administered the adenosine or inhale carbon dioxide. Comparing the images acquired one minute and 5 minutes after the injection or CO2 inhalation with the baseline, distinct changes …


Measuring The Effectiveness Of Light Concentration With The Catoptric Surface, Samatha Kodali Dec 2022

Measuring The Effectiveness Of Light Concentration With The Catoptric Surface, Samatha Kodali

McKelvey School of Engineering Graduate Student Theses & Dissertations

The Catoptric Surface is an array of mirrors arranged on the interior of a large window which serves to manipulate the effects of natural lighting inside the room. The framework for moving the mirrors uses an interface which connects various Raspberry Pis and Arduino Unos to move stepper motors that connect to each mirror and move them as desired by the user. This kind of light manipulation allows the atmosphere of the room to be modified using natural lighting rather than artificial lighting and can be useful for varying the way people interact with a space. The intensity at which …


Enhancing Human Schwann Cells Reparative Behavior Using Heparin/Collagen Layer-By-Layer Coatings, Luis Carlos Pinzon-Herrera Dec 2022

Enhancing Human Schwann Cells Reparative Behavior Using Heparin/Collagen Layer-By-Layer Coatings, Luis Carlos Pinzon-Herrera

Graduate Theses and Dissertations

When a peripheral nerve injury (PNI) occurs, the gold standard for tissue regeneration is the use of autografts. However, due to the secondary effects produced by multiple surgeries involved in the removal and implantation of autografts for very small lesions, it is possible to replace them with the use of Nerve Guide Conduits (NGCs). However, NGCs are limited to short lesions (less than 1 cm). This limitation is caused by the absence of compounds in the extracellular matrix (ECM) that autografts can provide. Since much of the regenerative process takes place on the NGC surface, our work aims to modify …


Ultrasound Mediated Tissue Growth In Bioinspired Scaffolds, Marco Fielder Dec 2022

Ultrasound Mediated Tissue Growth In Bioinspired Scaffolds, Marco Fielder

Graduate Theses and Dissertations

Porous scaffolds mechanically stimulated with ultrasound are used for the treatment of bone conditions such as osteoporosis or traumatic bone injury. However, one current issue in these treatment techniques is designing a scaffold structure with a high structural integrity that also does not impede tissue growth. A larger ultrasound wave transmission would also allow more of a scaffold to receive mechanical stimulation from ultrasound. Controlling mesenchymal stem cell seeding of tissue scaffolds also has potential for developing optimal seeding patterns to maximize or control tissue growth in the scaffold based on an individual’s physiology. There is also a need for …


Hierarchical Structure And Material Integration For Electrocatalytic Co2 Reduction, Hamed Mehrabi Dec 2022

Hierarchical Structure And Material Integration For Electrocatalytic Co2 Reduction, Hamed Mehrabi

Graduate Theses and Dissertations

CO2 released by the combustion of fossil fuels is driving significant changes to the earth’sclimate. The natural cycle for removing CO2 from the atmosphere, namely photosynthesis, cannot keep up with the rate at which it is being added. Developing engineering approaches to remove CO2 from the atmosphere is becoming essential to reduce these effects. Removal leads to further issues of carbon sequestration and favorable CO2 reuse strategies, including the electrochemical transformation of recovered CO2 to useful products such as fuels and materials. Copper is an important electrocatalyst for the CO2 reduction reaction (CO2RR) because of its unique capability for producing …


Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar Dec 2022

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …


Fiber-Based Time-Correlated Single Photon Counting As A Method For Investigating Metabolism During Tetanic Contraction Of Skeletal Muscle, Kathryn Miller Priest Dec 2022

Fiber-Based Time-Correlated Single Photon Counting As A Method For Investigating Metabolism During Tetanic Contraction Of Skeletal Muscle, Kathryn Miller Priest

Graduate Theses and Dissertations

Nicotinamide adenine dinucleotide (NAD) is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation (OXPHOS) [1-5]. The reduced form of NAD, NADH, is autofluorescent, making it a measurable characteristic in the investigation of metabolic changes. The fluorescence lifetime of NADH is dependent on the state of protein binding, specifically free or bound NADH, allowing for detection of metabolic shifts between glycolysis (free NADH) and OXPHOS (bound NADH) [6-16]. Fiber-coupled time-correlated single photon counting (TCSPC) equipped with an implantable needle probe can be used to measure NADH lifetime in vivo …


Evaluation Of Cellulose Nanocrystal Inks And Their Structural Characteristics For 3d Bioprinting Of Customized Scaffolds, Patrick William Kuczwara Dec 2022

Evaluation Of Cellulose Nanocrystal Inks And Their Structural Characteristics For 3d Bioprinting Of Customized Scaffolds, Patrick William Kuczwara

Graduate Theses and Dissertations

3D bioprinting of biological scaffolds requires control of the physicochemical properties of each unique structures. A promising material for control of properties is hydrogels, which can help create biomimetic scaffolds with controlled spatial arrangement of materials by integrating biological materials directly into layers during the bioprinting process. Nanocellulose offers a unique combination of properties including mechanical, biomimetic, and biocompatibility. These properties offer flexibility over the types, shapes, and applications of their printed hydrogel scaffolds, (i.e., tissue, drug, encapsulation). However, 3D bioprinting of nanocellulose-based hydrogels requires high loading percentages (i.e., >10 wt%) or chemical crosslinkers (i.e., bis(acyl)phosphane oxides (BAPO)). High solid …


Machine Learning For Target Detection Using Uwb Radar Sensor Networks, Dheeral Naresh Bhole Dec 2022

Machine Learning For Target Detection Using Uwb Radar Sensor Networks, Dheeral Naresh Bhole

Electrical Engineering Dissertations - Archive

Machine learning (ML) has recently been used to solve critical problems. This dissertation focuses on developing systems using Ultra-Wideband (UWB) wireless sensor networks and machine learning to solve critical tasks such as target detection in various challenging scenarios. These tasks have been researched for several years and efforts have been made to achieve universal solutions. In the first part of this dissertation, we have proposed a system to detect metallic targets in foliage environment. Mission critical systems need to be ready for the harsh working environment such as dense foliage, water bodies, rain, heavy winds and other natural challenges. Extreme …


Scalable Data-Driven Predictive Modeling And Analytics For Cho Process Development Optimization, Sarah Mbiki Dec 2022

Scalable Data-Driven Predictive Modeling And Analytics For Cho Process Development Optimization, Sarah Mbiki

All Dissertations

In 1982, the FDA approved the first recombinant therapeutic protein, and since then, the biopharmaceutical industry has continued to develop innovative and highly effective biological drugs for various illnesses1. These drugs are produced using host organisms that are modified to hold the genetic encoding of the targeted protein1. Of the many host organisms, Chinese hamster ovary (CHO) cells are often used due to capability to perform posttranslational modification (PTM): which allows human-like synthesis of proteins unlikely to invoke immunogenicity in humans 1,2.

Despite all the positive attributes, many challenges are associated with CHO cell cultures, …


Machine Learning For Early Detection Of Pediatric Sepsis, Glory Manson-Endeboh Dec 2022

Machine Learning For Early Detection Of Pediatric Sepsis, Glory Manson-Endeboh

Graduate Theses and Dissertations

Sepsis is a host response to infection in both adults and children. It contributes to approximately 1.7 million cases annually with nearly 270,000 annual deaths in the United States. In the United States, the financial burden of sepsis on survivors and their families including the hospitals is over $4.8 billion, at approximately $64,280 per hospitalization. The first goal of this thesis research is to develop efficient machine learning models to predict pediatric sepsis accurately for inpatients. The second objective is to develop machine learning methods to determine how early sepsis can be detected to mitigate mortality. We examine data collected …


Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu Dec 2022

Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide as a working fluid in a closed Brayton cycle is proving to be more efficient than a conventional steam-based Rankine engine. Understanding the heat transfer properties of supercritical fluids is important for the design of a working engine cycle. The thermophysical properties of supercritical fluids tend to vary non-linearly near the pseudo-critical region. Traditionally, empirical correlations are used to calculate the heat transfer coefficient. It has been shown in the literature and within our own studies that these correlations provide inaccurate predictions near the pseudo-critical line, where heat transfer may be deteriorated or enhanced, resulting from strong …


The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr. Dec 2022

The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr.

Publications and Research

On October 29, 2012, Superstorm Sandy impacted 443,000 people and caused nearly $19 billion (about $58 per person in the US) worth of damage within New York City. As part of the New York City infrastructure reparation plan, the Living Breakwaters project in Tottenville addressed coastal resilience, allocating $100M of public funds to a series of artificial breakwaters by the southwest coast of Staten Island. Each breakwater is constructed and designed to mitigate water flow in storm events. ECOncrete, a primary element of the breakwater, is a specialty cast cementitious product that is marine organism-friendly that encourages biocalcification and photosynthesis. …


Study Of Sustainable Development In Paper, Printing And Packaging Material Applications To Support Circular Economy, Prashant Ramesh Kotkar Dec 2022

Study Of Sustainable Development In Paper, Printing And Packaging Material Applications To Support Circular Economy, Prashant Ramesh Kotkar

Dissertations

To support circular economy and sustainability, the use of suitable material in paper, printing, and packaging industries, for several types of industrial printing material and printed product applications, plays a significant role for end user applications. Several types of packaging printing materials, specifically those finished with different printing technologies and exposed to different environmental conditions are targeted.

The purpose of this research study is to improve design and evaluation for paper, printing, and packaging material sustainability in end-user applications, to deal with the addressed sustainability issues brought by the paper, printing and packaging products end user groups. As the impacts …


Development Of A Tissue Engineered Cardiac Patch, Howard Herbert Dec 2022

Development Of A Tissue Engineered Cardiac Patch, Howard Herbert

All Dissertations

Cardiovascular Disease(CVD) is the leading cause of mortality in the developed world. CVD is most commonly manifested as atherosclerosis of the coronary arteries leading to Myocardial Infarction(MI). After MI, fibrosis of the ventricular wall leads to heart failure(HF), a pandemic affecting 26 million people globally. While therapies are continuously developed to combat HF, the treatment of choice, whole heart transplant, is limited by the availability of donor hearts. It is clear that there is a need to develop a long-term solution to combat HF and its enormous economic burden. Tissue Engineering and Regenerative Medicine holds promise as a possible solution …


Low Power Multi-Channel Interface For Charge Based Tactile Sensors, Samuel Hansen Dec 2022

Low Power Multi-Channel Interface For Charge Based Tactile Sensors, Samuel Hansen

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Analog front end electronics are designed in 65 nm CMOS technology to process charge pulses arriving from a tactile sensor array. This is accomplished through the use of charge sensitive amplifiers and discrete time filters with tunable clock signals located in each of the analog front ends. Sensors were emulated using Gaussian pulses during simulation. The digital side of the system uses SAR (successive approximation register) ADCs for sampling of the processed sensor signals.

Adviser: Sina Balkır


Learnfca: A Fuzzy Fca And Probability Based Approach For Learning And Classification, Suraj Ketan Samal Dec 2022

Learnfca: A Fuzzy Fca And Probability Based Approach For Learning And Classification, Suraj Ketan Samal

School of Computing: Dissertations, Theses, and Student Research

Formal concept analysis(FCA) is a mathematical theory based on lattice and order theory used for data analysis and knowledge representation. Over the past several years, many of its extensions have been proposed and applied in several domains including data mining, machine learning, knowledge management, semantic web, software development, chemistry ,biology, medicine, data analytics, biology and ontology engineering.

This thesis reviews the state-of-the-art of theory of Formal Concept Analysis(FCA) and its various extensions that have been developed and well-studied in the past several years. We discuss their historical roots, reproduce the original definitions and derivations with illustrative examples. Further, we provide …