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Biomethanation And Alkaline Wet Air Oxidation Of Water Hyacinth (Pontederia Crassipes) From Ozama River, Dominican Republic, Yessica A. Castro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Obtaining valuable products from environmental remediation waste is a sustainable approach that contributes to the ecological well-being of developing countries. In the present work, the feasibility of the water hyacinth anaerobic digestion as a post-weed management practice in the Ozama River (Dominican Republic) was demonstrated. The estimated energy required for harvesting was lower than that produced during digestion. The biomethanation of water hyacinth was improved by Alkaline Wet Air Oxidation (AWAO), a thermochemical pretreatment process that almost doubled the methane production rate and increased the yield by 24% when conducted at high temperatures. At lower temperatures, the methane yield of …

Accounting For Critical Attributes And Uncertainty In Flow-Ecology Relationships, Elizabeth Decker Morgan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Environmental flows are used to maintain streamflow for aquatic species in rivers while also sustaining human water requirements. While there are many approaches to develop environmental flows, they all rely on a strong conceptual understanding of flow-ecology relationships, which are often uncertain. Uncertainty in flow-ecology relationships can stem from using limited data to develop or test relationships or an incomplete understanding of the attributes inherent to each relationship, such as climate and land conditions. Accounting for these attributes and uncertainty in flow-ecology relationships is critical given mounting interest to develop and implement environmental flows at large scales, often with limited …

Cfd Analysis Of Acoustofluidic Channels And The Effects On Biologic Delivery., Zachary T. Long

Electronic Theses and Dissertations

T-cell transformation is an ever-expanding treatment for several types of cancer, with a potential to be adapted to other disorders in which the immune system plays a key role in the pathophysiology. Currently, all FDA approved chimeric antigen receptor (CAR) T-cell cancer therapies rely on transformation via viral transduction. However, viral transduction is plagued by poor consistency and the potential to create adverse immune reactions when T-cells are reintroduced into a patient. Other transformation methods are being explored, with an alternative called acoustofluidic sonoporation showing promise. In these procedures, cells are passed through a channel, of the millimeter scale, while …

Machine Learning Approaches For Lung Cancer Diagnosis., Ahmed Mahmoud Ahmed Shaffie

Electronic Theses and Dissertations

The enormity of changes and development in the field of medical imaging technology is hard to fathom, as it does not just represent the technique and process of constructing visual representations of the body from inside for medical analysis and to reveal the internal structure of different organs under the skin, but also it provides a noninvasive way for diagnosis of various disease and suggest an efficient ways to treat them. While data surrounding all of our lives are stored and collected to be ready for analysis by data scientists, medical images are considered a rich source that could provide …

Isomotive Dielectrophoresis For Enhanced Analyses Of Cell Subpopulations., Mohamed Zakarya Rashed

Electronic Theses and Dissertations

As the relentless dream of creating a true lab-on-a-chip device is closer to realization than ever before, which will be enabled through efficient and reliable sample characterization systems. Dielectrophoresis (DEP) is a term used to describe the motion of dielectric particles/ cells, by means of a non-uniform electric field (AC or DC). Cells of different dielectric properties (i.e., size, interior properties, and membrane properties) will act differently under the influence of dielectrophoretic force. Therefore, DEP can be used as a powerful, robust, and flexible tool for cellular manipulation, separation, characterization, and patterning. However, most recent DEP applications focus on …

Development And Applications Of In-Vitro And In-Silico Models Of The Cardiovascular System To Study The Effects Of Mechanical Circulatory Support., Moustafa Meki

Electronic Theses and Dissertations

Cardiovascular diseases (CVDs) are the leading cause of mortality globally. With ongoing interest in CVDs treatment, preclinical models for drug/therapeutic development that allow for fast iterative research are needed. Owing to the inherent complexity of the cardiovascular system, current in-vitro models of the cardiovascular system fail to replicate many of the physiological aspects of the cardiovascular system. In this dissertation, the main concern is with heart failure (HF). In advanced HF, patients may receive Left Ventricular Assist Devices (LVADs) as a bridge to transplant or destination therapy. However, LVADs have many limitations, including inability to adapt to varying tissue demand …

Investigating Topologic And Geometric Properties Of Synthetic And Natural River Networks Under Changing Climate, Shiblu Sarker

Electronic Theses and Dissertations, 2020-2023

River networks are important landscape features that collect and transport water, sediment and nutrients from regions of higher elevation to lower elevations. These networks have been studied for several decades from a range of geomorphological and hydrological perspectives. Investigating the geometric and topological properties of river networks is important for developing predictive models describing the network dynamics under changing climate as well as for quantifying the physical processes operating upon them. Although these networks have been characterized for a wide range of geomorphic properties, topological properties, and in particular, spectral properties of river networks received limited attention. In this dissertation, …

Quantifying Mucosal Hemodynamics In A Murine Model Of Ulcerative Colitis With Diffuse Reflectance Spectroscopy, Elizabeth A. Bullard, Ariel I. Mundo, Shelby N. Bess, Kathryn P. Miller

Biomedical Engineering Undergraduate Honors Theses

Ulcerative colitis (UC) is a gastrointestinal, autoimmune disease that causes ulceration and inflammation of the colon with an incidence 10 out of every 100,000 people in North America and Western Europe. Though the exact etiology is uncertain, a number of studies have shown that inflammatory cells along with environmental factors, genetics, and lifestyle habits can contribute to the sustained inflammatory response. In order to determine the cellular mechanism behind relapse and remission of UC, researchers have frequently employed immunohistochemistry, western blotting and gene sequencing, but these destructive analysis methods require the removal of a sample, necessarily limiting these methods to …

Evaluating Cellular Response Of Different Valve Interstitial Cell (Vic) Phenotypes To Angiotensin I, Smit Patel

Biomedical Engineering Undergraduate Honors Theses

Calcific Aortic Valve Disease (CAVD), one of the leading causes of death in the United States, is characterized by diminished functioning and limited movement of the aortic valve (AV) due to increased thickening, disorganized extracellular matrix elastin fibers, increased collagen content, and abnormal deposition and formation of calcium nodules on the AV [1, 2]. There are two types of CAVD: i) Aortic valve sclerosis (AVS), in which patients suffer from tissue hardening, fibrosis, and early calcification, and ii) calcific aortic stenosis (CAS), representative by excessive calcification on the AV and reduced AV opening, are the two main forms of CAVD …

Evaluation Of The Cytotoxyc Effects Of Lmdf5-7 On A Human T-Cell Leukemia Cell Line, Andrea F. Ibarra Chacon

Open Access Theses & Dissertations

According to World Health Organization (WHO), cancer is the second leading cause of death worldwide, with 9.6 million deaths in 2018 . In the United States, an estimated 434,982 people were living with cancer during 2017 . Leukemia is the most common blood cancer in children from birth to 14 years old . In particular, Hispanic children in the United States experience a higher incidence rate of leukemia . Therefore, the discovery of novel cancer therapies is necessary to help those affected survive the disease. A new compound, LMDF5-7 was investigated and found to have anticancer properties that can help …

Evaluation Of Recycled Plastic Pins As Shear Keys In Mse Wall Base, Prabesh Bhandari

Civil Engineering Dissertations - Archive

Mechanically Stabilized Earth (MSE) walls have been widely used as retaining structures due to their flexible nature, a better tolerance against differential settlement, and many other factors. However, external stability problems of MSE walls have been an issue in North Texas over decades. Lateral displacement of the wall occurs, giving rise to sliding failure, when there is insufficient shear strength at the wall base to produce adequate frictional resistance. Such failures can cause significant maintenance, repair, and cost implications for the state department of transportation. Furthermore, MSE walls also undergo global failure due to weak soil conditions along with high …

Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen

Biomedical Engineering Undergraduate Honors Theses

Cell division is a vital biological process for growth and development in both single and multi-cellular organisms—whereby the cell must duplicate its organelles and genome in entirety and appropriately distribute the copied contents to the daughter cells. Cells undergo a cycle of two distinct phases: interphase and mitosis. During interphase, the cell replicates its genomic DNA (in the form of chromosomes) located within the nucleus. DNA replication is carried out in a euchromatin state, where the chromosome structure is loose and easily accessible by DNA polymerase and other replication enzymes. Upon the completion of replication, chromatin is condensed into highly …

Quantification Of Superoxide Production In Cells Treated With L-Buthionine Sulfoximine, Rebekah Townsley

Biomedical Engineering Undergraduate Honors Theses

Hydroxyl radicals, superoxides, and hydrogen peroxides are common reactive oxygen species (ROS) that are produced by the mitochondria during cellular respiration [1]. Signal transduction pathways in the mitochondria are used to maintain the balance of ROS. However, when these mechanisms fail to regulate ROS properly, it causes oxidative damage and can lead to the development of various diseases such as cancer, respiratory, neurodegenerative, and cardiovascular diseases. L-buthionine sulfoximine (BSO) has been used previously to induce oxidative stress by inhibiting the γ-GCS enzyme used to synthesize glutathione, an antioxidant used to convert ROS to water [3]. BSO reduces glutathione production, thus …

Economic And Ecosystem Impacts Of Gm Maize In South Africa, Kristiina Ala-Kokko

Graduate Theses and Dissertations

White maize in South Africa is the only staple crop produced on a widespread commercial basis for direct human consumption using genetically modified (GM) cultivars. Using a combined economic and environmental approach, we estimate the total welfare benefits attributable to GM white maize in South Africa for 2001-2018 are $694.7 million. Food security benefits attributable to GM white maize in South Africa also manifest through an average of 4.6 million additional white maize rations annually. To achieve these additional annual rations using conventional hybrid maize, the additional land required would range from 1,088 hectares in 2001 to 217,788 hectares in …

Mechanical Analysis Of A Heterogeneously Integrated Silicon Photonic Interposer, Erica Charlene Graham

Legacy Theses & Dissertations (2009 - 2024)

Overcoming the bandwidth bottleneck in conventional interconnects necessitates transitioning to alternative scaling paradigms. Silicon (Si) photonics is considered a disruptive technology, capable of meeting the growing demands for higher bandwidth, low latency, and power efficiency. By leveraging the intrinsic properties of optical signals and manufacturing compatibility of Si, the co-integration of Si photonics and complementary-metal-oxide-semiconductor (CMOS) circuitry leading to terabit data speeds for next generation data communication can be realized. Heterogeneously integrating Si photonic functionality with well-established CMOS technology in an Si photonic interposer architecture simultaneously provides independent optimization as well as close integration of both technologies in one platform. …

Modeling And Monitoring Of Water Quantity And Quality In Permeable Pavement Systems Using Geophysical Equipment, Abby Klimowicz

Honors Scholar Theses

Permeable pavements are a type of low impact development (LID) that reduces runoff by increasing the permeability of developed surfaces. Less runoff helps protect the surrounding ecosystems from erosion and pollution. Without pools of accumulating runoff, the potential for the development of ice on roads and parking lots is also decreased. However, sufficient research on the movement of water and the ions dissolved in it through the permeable pavement system has not been completed. In this study, geophysical equipment was used to observe how moisture, measured as volumetric water content (VWC), and ions, approximated by electrical conductivity, pass through constructed …

Machine Learning-Based Recognition On Crowdsourced Food Images, Aditya Kulkarni

Honors Scholar Theses

With nearly a third of the world’s population suffering from food-induced chronic diseases such as obesity, the role of food in community health is required now more than ever. While current research underscores food proximity and density, there is a dearth in regard to its nutrition and quality. However, recent research in geospatial data collection and analysis as well as intelligent deep learning will help us study this further.

Employing the efficiency and interconnection of computer vision and geospatial technology, we want to study whether healthy food in the community is attainable. Specifically, with the help of deep learning in …

Development Of A Wearable Finger Exoskeleton For Rehabilitation, Carlos Hernandez-Santos, Yasser A. Davizón, Alejandro Said, Rogelio Soto, L. C. Felix-Harran, Adriana Vargas-Martinez

Electrical and Computer Engineering Faculty Publications

This research work shows a new architecture of a novel wearable finger exoskeleton for rehabilitation; the proposed design consists of a one degree of freedom mechanism that generates the flexion and extension movement for the proximal, medial and distal phalange of the fingers to assist patients during the rehabilitation process, after neurological trauma, such as a stroke. The anatomy and anthropometric measures for the hand were used to define the design of the mechanism. In the analytic part, the representative equations for the forward and inverse kinematic analysis of the fingers are obtained, also a dynamic analysis is presented. The …

Environmental Impacts Of Overdesign In Small Community Water Resource Recovery Facilities, Andrew Pham

Department of Environmental Engineering: Theses and Other Student Research

Although water resource recovery facilities (WRRFs) reduce environmental impacts related to water quality, their construction and operation result in negative environmental impacts in other categories. Past research into Nebraska WRRFs investigated variables determining energy intensity, opportunities and barriers for energy efficiency improvements, and environmental impacts of the construction and operation phase. This leads to the research question of what design practices can be considered to reduce the environmental impacts.

The Life Cycle Assessment (LCA) methodology was used to evaluate and compare the inventory and environmental impacts of nine small WRRFs, most of which are serving slow growing or declining populations. …

Photomodulatory Effects On Insulin Secreting Beta Cells, Sheccid Alejandra Loya

Bioengineering Theses - Archive

Diabetes mellitus is a chronic metabolic disease characterized by increased blood glucose levels and affects more than 8% of people worldwide (Rutter et. al, 2015). Typically, diabetes is divided into two large subcategories: type 1 diabetes (T1D) and type 2 diabetes (T2D). T1D is an autoimmune disorder caused by the attack of insulin secreting cells by t-cell mediated inflammatory response (Khrraoubi & Darwish, 2015). Currently, islet transplants offer a clinical treatment for restoration of glucose control. However, the current procedure may not be optimal as many transplanted islets do not survive because of the stresses induced during the process (Miki …

Mapping Three Dimensional Interactions Between Biomolecules And Electric Fields., Joseph Patrick Brian P.E.

Electronic Theses and Dissertations

Electroporation is a technique that induces the formation of open pores in cell membranes by the application of an electric field. Electroporation is widely practiced in research and clinical work for transfection of genetic sequences and drug molecule transport through the membrane barrier. However, a full theoretical explanation of the molecular mechanisms and thermodynamics responsible for pore formation, structure, and longevity does not yet exist. Advances in molecular dynamics simulations have enabled theoretical studies of electroporation with previously unobtainable fidelity spanning biologically relevant timescales. All-atom simulations utilizing the recently developed method of computational electrophysiology demonstrate that pore size correlates to …

Simulation Of Fracture Strength Improvements Of A Human Proximal Femur Using Finite Element Analysis., Waleed Ebraheem Alim

Electronic Theses and Dissertations

The most common hip fracture in the elderly occurs as a result of a fall to the side with impact over the greater trochanter resulting in a fracture of the proximal femur. The fracture usually involves the femoral neck or the intertrochanteric region. It has recently been determined that the fracture crack of a hip fracture typically initiates on the superior-lateral cortex of the femoral neck and then propagates across the femoral neck, resulting in a complete fracture. The strength of the superior-lateral cortex of the femoral neck is likely determined by the combined properties of the generally thin cortex …

Monitoring Fgf1-Treated Skin Wounds With Label-Free Multiphoton Microscopy, Gianna Busch

Biomedical Engineering Undergraduate Honors Theses

Chronic skin wounds pose a significant threat to public health, affecting as many as 5.5 million people in the United States every year and costing the healthcare system $10 billion annually^1,2. These wounds are associated with prolonged inflammation, poor vascularization, increased infection risk, and high mortality rates^3,4. There is significant interest in developing and testing a variety of biologics to promote wound healing. However, quantitative evaluations of healing are typically limited to measurements of wound size, and there is a critical need to develop quantitative biomarkers sensitive to different aspects of the healing process. Label-free multiphoton …

Mapping The Domain Of Rna Helicase Ddx1 That Interacts With The Ns1 Of Influenza A Viruses, Elise Wyatt

Biomedical Engineering Undergraduate Honors Theses

Of the known influenza virus strains, influenza A viruses (IAVs) are the most catastrophic due to their highly contagious nature and possibly life-threatening symptoms. IAVs invade a host cell and enter the nucleus where they use the cell’s nuclear machinery for replication of their viral RNA genome which is then exported to neighboring cells to establish a productive infection. Host pathogen recognition receptors (PRRs) respond to viral infection by signaling the cell to produce type I interferons (IFNs) to fight the foreign invader. Non-structural protein 1 (NS1) of IAVs, a major component in the regulation of viral replication, opposes host …

Developing Aligned Nerve Scaffolds In A 3d Type-I Collagen Gel, Gabriel David

Biomedical Engineering Undergraduate Honors Theses

Despite significant progress in the field of peripheral nerve repair, clinical success is still limited, leaving millions to suffer from peripheral neuropathy with billions spent every year for treatment. Nerve repair methods that are capable of maximizing the regenerative properties of peripheral nerves are greatly desired in the field of medical science. This research aims to fill the gap between modern methods and the future of nerve repair by creating type-I collagen scaffolds with aligned degradation pores that will assist and nurture nerves growing through them. This is achieved by incorporating adipose stem cells into type-I collagen hydrogels and aligning …

Thruster Communication For Subsurface Environments; Turning Waste Noise Into Useful Data, Stephen Cronin

Doctoral Dissertations and Master's Theses

Acoustic communication serves as one of the primary means of wirelessly communicating underwater. Whereas much of the developments in the field of wireless communication have focused on radio frequency technology, water highly absorbs radio waves rendering the link not feasible for most all subsurface operations. While acoustic links have enabled new capabilities for systems operating in this challenging environment, it has yet to reach the commodity availability of radio systems, meaning that an entire class of small, low-cost systems have been unable to make use of these links. The systems in question are primarily autonomous underwater vehicles (AUVs), as they …

Air Traffic Controllers’ Occupational Stress And Performance In The Future Air Traffic Management, Hui Wang

Doctoral Dissertations and Master's Theses

As demand for unmanned aerial vehicle (UAV) operations increases, it is vital to understand its effects on air traffic controllers and the safety of the national airspace system. This study’s primary purpose is to determine how UAVs that operate in controlled airspace would influence air traffic controllers’ occupational stress and performance. In a within-subject experimental research design, 24 participants sampled from a university’s undergraduate Air Traffic Management (ATM) program completed three different air traffic control (ATC) scenarios on an en route ATC simulation system. The degree of UAV automation and control were varied in each scenario. The participants’ stress levels, …

Validation Of A Two-Dimensional Clinostat Design To Provide Functional Weightlessness To Custom Gas Exchange Vessels, Collin R. Topolski

Doctoral Dissertations and Master's Theses

Understanding the impacts of microgravity on bacteria is vital for successful long duration space missions. In this environment, bacteria have been shown to become more virulent, more resistant to antibiotics and form more biofilms. To learn more about these phenomena, many experiments must be sent to the International Space Station, which is cost- and time prohibitive. Instead, the use of ground-based analogs is advantageous to define preliminary results that can later be verified with a space-based experiment. This research explored the development of an innovative 2D clinostat for simulating microgravity using bacteria. Computational fluid dynamics, standards established by previous literature …

Data-Driven Architecture To Increase Resilience In Multi-Agent Coordinated Missions, D. F.

Doctoral Dissertations and Master's Theses

The rise in the use of Multi-Agent Systems (MASs) in unpredictable and changing environments has created the need for intelligent algorithms to increase their autonomy, safety and performance in the event of disturbances and threats. MASs are attractive for their flexibility, which also makes them prone to threats that may result from hardware failures (actuators, sensors, onboard computer, power source) and operational abnormal conditions (weather, GPS denied location, cyber-attacks). This dissertation presents research on a bio-inspired approach for resilience augmentation in MASs in the presence of disturbances and threats such as communication link and stealthy zero-dynamics attacks. An adaptive bio-inspired …

Estimating Irrigation In Rice Fields With A Water Balance Approach, Kristen Trinh

Biological and Agricultural Engineering Undergraduate Honors Theses

Global food production must increase to meet the demand associated with increased population growth, so irrigation water use will continue to rise. Therefore, it is important to monitor water usage particularly when an irrigation flowmeter is unavailable. A field water balance was created for a selection of rice fields in East-central Arkansas under observation in 2018 and 2019. From those, irrigation inputs are deduced from the water balance alone. First, each field had sensors that collected water table level (WTL) data. Next, other water inputs and outputs such as precipitation and evapotranspiration (ET) were collected from two modeled sources. The …