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Full-Text Articles in Engineering

Investigating The Effect Of Pancreatic Cancer Tumor-Derived Extracellular Vesicles On Schwann Cell Activation, Isabel Powers May 2023

Investigating The Effect Of Pancreatic Cancer Tumor-Derived Extracellular Vesicles On Schwann Cell Activation, Isabel Powers

Biomedical Engineering Undergraduate Honors Theses

Pancreatic cancer is one of the deadliest diseases because it is hard to identify in its early stages, has high chemoresistance, and early metastasis. Because of these traits, it is often associated with perineural invasion (PNI), where the cancer travels to the nervous system. Schwann cells (SC) are associated with both metastasis and PNI when activated. The purpose of this study was to determine if and how pancreatic tumor-derived extracellular vesicles (TEVs) can activate SC in PNI. This experiment was performed by embedding Schwann cells in a hydrogel to model the tumor microenvironment and treating them with isolated extracellular vesicles …


Fuel Prediction: Determining The Desirable Stops For The Cheapest Road Trips, Maxx Smith May 2023

Fuel Prediction: Determining The Desirable Stops For The Cheapest Road Trips, Maxx Smith

Computer Science and Computer Engineering Undergraduate Honors Theses

Current technology has given rise to many advanced route-planning applications that are available for use by the general public. Gone are the days of preparing for road trips by looking at a paper map for hours on end trying to determine the correct exits or calculate the distance to be traveled. However, with the use of modern technology, there is a certain aspect of forward-thinking that is now lost with planning a road trip. One of the biggest constraints that often gets left on the backburner is deciding when and where to stop to refuel the car. This report is …


Innovations In Football Protective Headgear, Henry Bethel May 2023

Innovations In Football Protective Headgear, Henry Bethel

Civil Engineering Undergraduate Honors Theses

Adding impact reduction to football protective headgear decreases the reactionary acceleration experienced by the cranium. Utilizing an iteration of the National Operating Committee for Standards in Athletic Equipment (NOCSAE) method of testing per ASTM F429, a drop tower was fabricated, and 27 drop tests were conducted upon a standard helmet (control) and the Summerlin model helmet (test), measuring the maximum acceleration experienced by each drop. Drop tests involved variable heights and test angles with three drops being made per combination. The Summerlin model drops were conducted until failure, occurring at the third 3” drop at the “front” location at an …


Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France May 2023

Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France

Computer Science and Computer Engineering Undergraduate Honors Theses

The field of computing as we know it today exists because of the contributions of numerous female mathematicians, computer scientists, and programmers. While working with hardware was viewed as “a man’s job” during the mid-20th century, computing and programming was viewed as a noble and high-paying field for women to occupy. However, as time has progressed, the U.S. has seen a decrease in the number of women pursuing computer science. The idea that computing is a masculine discipline is common in the U.S. today for reasons such as male-centered marketing of electronics and gadgets, an inaccurate representation of what it …


Detecting Pathobiomes Using Machine Learning, Valerie Jackson, Valerie Jackson May 2023

Detecting Pathobiomes Using Machine Learning, Valerie Jackson, Valerie Jackson

Industrial Engineering Undergraduate Honors Theses

Machine learning is a field with high growth potential due to the overall continuous progressions, developments, advancements, and improvements caused by the way it is used to help interpret and use large amounts of data [1]. One type of data that can be collected and analyzed by these machine learning models is data that is associated with DNA and information that the DNA gives. The research will be focusing specifically on using machine learning technology to detect pathobiomes indicative of salmonella pork. The pathobiome associated with salmonella is very similar to others, and this causes a problem for classification/detection with …


Improving Tribological Properties Of Polydopamine/Polytetrafluoroethylene Coatings Through Incorporating Core-Shell Nanoparticles And Laser Surface Texturing, Firuze Soltani-Kordshuli May 2023

Improving Tribological Properties Of Polydopamine/Polytetrafluoroethylene Coatings Through Incorporating Core-Shell Nanoparticles And Laser Surface Texturing, Firuze Soltani-Kordshuli

Graduate Theses and Dissertations

Polytetrafluoroethylene (PTFE) is a widely used polymer that has unique properties such as chemical and temperature resistance, corrosion resistance, low maintenance cost, and a very low coefficient of friction (COF). These distinctive properties have made PTFE a promising candidate for industrial applications where surfaces are in relative motion. PTFE can be utilized as a thin film solid lubricant to significantly reduce the friction between moving surfaces. However, PTFE coatings have low cohesion and poor adhesion to the substrate resulting in its low wear resistance. This fact limits the application of PTFE coatings in load-bearing situations. To address these limitations, an …


On The Micro-Mechanical Property Characterization And Bulk-Volume Behavior Prediction Of Additively Manufactured 17-4 Ph Stainless Steels, David González-Niño May 2023

On The Micro-Mechanical Property Characterization And Bulk-Volume Behavior Prediction Of Additively Manufactured 17-4 Ph Stainless Steels, David González-Niño

Graduate Theses and Dissertations

Selective laser melting is an additive manufacturing technology that opens the possibility to manufacture components with complex geometries that are difficult with traditional manufacturing techniques which could benefit engineering applications such as aviation or structural engineering. However, the lack of a reliable universal predictive model for selective laser melting components could impede the full implementation in industrial applications. Therefore, this dissertation investigates the mechanical behavior of selective laser melting 17-4 PH stainless steel under ultra-low cycle fatigue regime and propose a novel micro-mechanical based modeling using statistical and representative volume element. The first phase of this project examined the mechanical …


Experimental Design For Determining The Cyclic Behavior Of Skewed Reduced Beam Section Moment Connections Having Composite Slabs, Paul Chabaud May 2023

Experimental Design For Determining The Cyclic Behavior Of Skewed Reduced Beam Section Moment Connections Having Composite Slabs, Paul Chabaud

Graduate Theses and Dissertations

This paper details the experimental design for determining the cyclic behavior of skewed Reduced Beam Section (RBS) moment connections having composite slabs. The effects of composite concrete slabs on skewed RBS connections subjected to cyclic seismic prequalification loading are addressed in this test setup. Full-scale double-sided RBS SMF specimens representing both interior and exterior column connections are designed and fabricated in this work. Experimental test fixturing and a lateral load application setup within the existing Grady E. Harvell Civil Engineering Research and Education Center (CEREC) are designed. All cyclic loading protocols required for the prequalification testing are described herein. Prequalification …


Development Of Self-Stressing Ultra High-Performance Concrete Using Expansive Chemical Admixtures, Lane Edwards May 2023

Development Of Self-Stressing Ultra High-Performance Concrete Using Expansive Chemical Admixtures, Lane Edwards

Graduate Theses and Dissertations

This study investigated the effects of expansive chemical admixtures on ultra-high performance concrete (UHPC) and self-stressing mechanisms. A literature review was performed to determine different types of expansive admixtures for feasibility of the self-prestressing concept. Ultimately it was decided that type-k cement, made by combining Komponent admixture with conventional UHPC, was the most suitable option due to its effects on wet and hardened concrete properties. Mix designs with varying amounts of Komponent were developed to test the effects the admixture had on various properties. Tested properties included, workability, compressive strength, expansion, short-term shrinkage, long-term shrinkage, and developed prestress. The development …


On The Feasibility Of Embedding Fe-Sma Short-Fibers In Ultra-High-Performance Concrete For Self Prestressing, Gavin Briggs May 2023

On The Feasibility Of Embedding Fe-Sma Short-Fibers In Ultra-High-Performance Concrete For Self Prestressing, Gavin Briggs

Graduate Theses and Dissertations

Prestressing concrete is common practice in the construction industry. Current prestressing methods are often used for large, straight members and come with geometric limitations for curved or thin-walled members. Shape memory alloy short fibers embedded within concrete mixes may allow for the prestressing of geometries not possible with traditional methods. This study reviews past research on prestressing concrete with shape memory alloys, evaluates the achievable recovery stress within an Fe-SMA (when deformed at room temperature), and examines the mechanical behavior of Ductal dark grey UHPC when heated to 250 °C. The flexural behavior, compressive strength, and fiber-to-concrete bond strength of …


Modeling And Control Strategies For A Two-Wheel Balancing Mobile Robot, John Alan Moritz May 2023

Modeling And Control Strategies For A Two-Wheel Balancing Mobile Robot, John Alan Moritz

Graduate Theses and Dissertations

The problem of balancing and autonomously navigating a two-wheel mobile robot is an increasingly active area of research, due to its potential applications in last-mile delivery, pedestrian transportation, warehouse automation, parts supply, agriculture, surveillance, and monitoring. This thesis investigates the design and control of a two-wheel balancing mobile robot using three different control strategies: Proportional Integral Derivative (PID) controllers, Sliding Mode Control, and Deep Q-Learning methodology. The mobile robot is modeled using a dynamic and kinematic model, and its motion is simulated in a custom MATLAB/Simulink environment. The first part of the thesis focuses on developing a dynamic and kinematic …


Bond-Breaker Properties Of Different Media For Concrete Pavement Design, Andres Calzacorta May 2023

Bond-Breaker Properties Of Different Media For Concrete Pavement Design, Andres Calzacorta

Graduate Theses and Dissertations

Currently Arkansas requires a layer of asphalt as the main bond-breaker over cement treated base for rigid pavement design. The study presented in this paper aims to replicate the results from previous research which demonstrated the bond-breaker properties of concrete curing compounds and geotextiles. Bond-breakers are materials applied to the surface of stabilized bases to reduce the interaction between the base and a pavement cement concrete layer. The excessive interaction between these two layers can lead to cracking in the overlay and reduction of the serviceability life of concrete. The curing compound was applied in a single application (SA, 200 …


Pda/Ptfe Solid Lubricant Coating For 60niti Applications, Charles Richey Miller May 2023

Pda/Ptfe Solid Lubricant Coating For 60niti Applications, Charles Richey Miller

Graduate Theses and Dissertations

The intermetallic alloy 60NiTi has a unique combination of high hardness and low elastic modulus, which makes it highly resistant to dents. Additionally, 60NiTi is extremely corrosion resistant and chemically inert. These properties make 60NiTi a desirable material for challenging mechanical component applications with high contact stresses and in harsh environments. However, lubrication issues have hindered the use of 60NiTi because it has poor tribological performance if it is not properly lubricated. The mechanical properties of hardened 60NiTi and its microconstituents were studied by nanoindentation. This study showed that the bulk properties of 60NiTi are driven by the properties of …


Geophysical Assessment Of Internal Erosion Damage At The Crawford County Levee, Samuel Ross Hokett May 2023

Geophysical Assessment Of Internal Erosion Damage At The Crawford County Levee, Samuel Ross Hokett

Graduate Theses and Dissertations

Levee failures during flooding events can result in catastrophic loss of life and property. Soil erosion during high water events is a primary cause of levee failures. Accordingly, this research focuses on the geophysical assessment of internal erosion damage in levees. This thesis presents a case study utilizing Capacitively Coupled Resistivity (CCR), Direct Current Electrical Resistivity Tomography (DC ERT), and Multichannel Analysis of Surface Waves (MASW) to assess internal erosion damage at the Crawford County Levee System in Van Buren, AR, that occurred during the 2019 Arkansas River flood. Geophysical surveys acquired included longitudinal CCR, DC ERT, and MASW lines …


Investigating The Impact Of International Education On Cultural Understanding, Health Disparities And Collaboration Through Project-Based Learning, Breanna Kilgore May 2023

Investigating The Impact Of International Education On Cultural Understanding, Health Disparities And Collaboration Through Project-Based Learning, Breanna Kilgore

Biomedical Engineering Undergraduate Honors Theses

Global health is an interdisciplinary field emphasizing international health issues, causes, and solutions based on cultural and global understanding. We have all witnessed how crucial global health is with the global COVID-19 crisis that has affected everyone. To effectively work to solve global health issues, people from different backgrounds must work together to complete a common goal. Before problem solving begins, gaining a basic understanding of cultural differences and collaborating with different people is an essential skill to have. Previous studies have demonstrated the usefulness of study abroad experiences and international service-learning opportunities in promoting collaborations, cultural competency and personal …


Correlation Of Intracellular Metabolites With Optical Metabolic Imaging In Polarized Macrophages As Indicators Of Metabolic Reprogramming, Abby Claire Denison, Shelby Bess May 2023

Correlation Of Intracellular Metabolites With Optical Metabolic Imaging In Polarized Macrophages As Indicators Of Metabolic Reprogramming, Abby Claire Denison, Shelby Bess

Biomedical Engineering Undergraduate Honors Theses

Macrophages are a type of immune cell that are characterized by their ability to differentiate into various active phenotypes based on environmental stimuli. They can generally be classified as one of two extremes: inflammatory/M1 or wound-healing/M2. Macrophage populations in vivo, however, are rarely homogenous, and since macrophages play vital roles in the immune response, particularly in the context of the tumor microenvironment (TME), it’s important to be able to investigate and understand heterogenous macrophage populations to develop more effective treatments. Recently, autofluorescence imaging such as multiphoton microscopy and fluorescence lifetime imaging microscopy (FLIM) of metabolic cofactors NADH and FAD have …


Optimizing Three-Dimensional Bioengineered Co-Cultures For The Study Of Fibrotic Spinal Cord Injury, Sarah Aly May 2023

Optimizing Three-Dimensional Bioengineered Co-Cultures For The Study Of Fibrotic Spinal Cord Injury, Sarah Aly

Biomedical Engineering Undergraduate Honors Theses

Spinal cord injuries (SCIs) have major physical implications on those affected[1]. There are two main types of scarring that occur after injury; they are known as the glial and fibrotic scar. The injured site causes an altered micro-environment which transforms astrocytes from their normal to reactive state, thus inhibiting axonal regeneration. The effect of reactive astrocytes on fibrotic scarring is not fully understood due to limited study[2,3]. Using Three-Dimensional (3D) bioengineered co-cultures of astrocytes and neuroblasts the pathological environment can be replicated and manipulated to further the study of fibrotic scarring. Temperature casted co-cultures were successfully …


Automated Visualization Pipeline For Near Real-Time Risk Management System, Paris Joslin May 2023

Automated Visualization Pipeline For Near Real-Time Risk Management System, Paris Joslin

Industrial Engineering Undergraduate Honors Theses

In modern society, technological capabilities and the amount of data readily available to users continue to grow exponentially. Many have adopted these new capabilities but lack the infrastructure needed to efficiently utilize high-powered software and programs. Without a method to collect, store, and process large datasets in real-time, individuals and businesses can quickly become overwhelmed, inhibiting effective decision-making processes. There is potential to improve decision-making abilities by enhancing the computing infrastructure. To accomplish this task, we will explore the ideas surrounding High Performance Computing (HPC) and data visualization software. High Performance Computing is the ability to process data and perform …


Testing The Effects Of Different Designs On The Physical Properties Of 3d-Printed Watch Bands, Ross Harper May 2023

Testing The Effects Of Different Designs On The Physical Properties Of 3d-Printed Watch Bands, Ross Harper

Industrial Engineering Undergraduate Honors Theses

Technological innovation progresses at an ever-increasing rate, and this is especially true in the field of 3D-printing. 3D-printing has become popular in manufacturing settings and among amateur hobbyists alike, largely because 3D-printers can fabricate an enormous number of designs from an array of materials and allow for fine-tuning through several setting options. Individuals with proficient 3D-printing abilities can produce a nearly infinite number of components for diverse applications in manufacturing, recreation, ergonomics, and many more. Some individuals use their skills to create functional substitutes for name-brand items, including bands to fit and be worn with a smart watch. However, little …


Lead Distribution Modeling For Supply Chains With A Large Number Of Items, Wesley Tate May 2023

Lead Distribution Modeling For Supply Chains With A Large Number Of Items, Wesley Tate

Industrial Engineering Undergraduate Honors Theses

Adding randomness into a simulation model allows for a better understanding of the variation that can occur in a real-life setting. This paper documents the methodology used to recommend a set of distribution models to cover administrative and production lead times for the simulation program involving hundreds of thousands of items. The problem of distribution fitting for large datasets is addressed, with histograms, Q-Q, and P-P plots being used to verify models in addition to goodness-of-fit test statistics. Variable level reduction using frequency and distribution matching approaches are outlined followed by the use of random forest modeling to identify key …


Low-Cost Microstereolithography 3d Printing With Microfluidic Microsampling Applications, Lauren Twombly May 2023

Low-Cost Microstereolithography 3d Printing With Microfluidic Microsampling Applications, Lauren Twombly

Chemistry & Biochemistry Undergraduate Honors Theses

The growing field of stereolithography 3D printing has welcomed a new age ofmicrofluidic device fabrication techniques. When compared to previous planar fabrication techniques such as soft-lithography, stereolithography 3D printing offers highly automated procedures, reduced fabrication times, and greater complexity of device features. To date, the greatest tradeoff for 3D printing in microfluidic device fabrication is poorer resolution when compared to soft-lithography which can produce feature sizes on the nanometer scale. The poorer resolution of 3D printing limits the feasible size of features. While highly sophisticated 3D printers are capable of achieving sub 10 μm resolution, these instruments are incredibly expensive …


The Impact Of A Carbon Tax On Emissions, Jessica Creech May 2023

The Impact Of A Carbon Tax On Emissions, Jessica Creech

Industrial Engineering Undergraduate Honors Theses

A carbon tax is an economic policy that aims to reduce various emissions to serve the protection of the environment. Versions of this policy have been implemented in multiple countries across the world to introduce a cost for contributing to environmental damage. Since climate change is prevalent in today’s world, finding an effective method to reduce emissions is essential. However, many countries hesitate to utilize a carbon tax for two reasons. First, they are unsure if the carbon tax is effective at reducing emissions. Second, there is a concern that the implementation of such a tax will be detrimental to …


Exploring The Effects Of Microarchitecture On Astrocyte Behavior And Vascular Remodeling In Spinal Cord Injury, Devin Gerber May 2023

Exploring The Effects Of Microarchitecture On Astrocyte Behavior And Vascular Remodeling In Spinal Cord Injury, Devin Gerber

Biomedical Engineering Undergraduate Honors Theses

Spinal cord injury (SCI) is a common condition and is characterized by traumatic and progressive damage that results in limited neuron regeneration and thus a restricted recovery. In SCI, the vasculature is also severely damaged, which exacerbates inflammation at the injury site. Specifically, insufficient angiogenesis occurs at the site of injury due to the fibrotic pathological microenvironment1 . SCI also leads to the formation of a fluid-filled cavity and thus gliosis and fibrosis, forming a dense glial and fibrotic scar around the cavity. The microenvironment at the injury site plays a significant role in astrocyte behavior, promoting the transformation of …


Study Of The Stability Of Heparin/Collagen Layer-By-Layer Coatings, Hector M. Apodaca Reyes May 2023

Study Of The Stability Of Heparin/Collagen Layer-By-Layer Coatings, Hector M. Apodaca Reyes

Chemical Engineering Undergraduate Honors Theses

Pairing heparin with collagen-based medical implants has opened a whole new area of research for enhancing the desired effect of current implants. In fact, heparin (HEP) and collagen (COL) layer-by-layer (LbL) coatings have shown impressive results in forming polyelectrolyte multilayers. It has been already seen on skin grafts, nerve guide conduits (NGCs), and drug delivery devices yielding promising results. Due to being a simple, cost-efficient, and versatile option to fabricate thin biomimetic films, this self-assembly technique is one of the most effective methods to immobilize extracellular matrix (collagen and heparin) onto medical devices and implants. Even though previous studies have …


Automation Of Life Cycle Assessment, Jacob Hickman May 2023

Automation Of Life Cycle Assessment, Jacob Hickman

Graduate Theses and Dissertations

An automation program, named Jacob LCA, was created to help perform life cycle assessment (LCA). The program uses a template file to perform controlled and consistently ordered actions with the LCA program, SimaPro, and effectively removes the need for manual user input. It can be set to run using data from one or more life cycle inventory (LCI) files, which allows for rapid iteration and testing of data. It also partially addresses some of the limitations of LCA by establishing a procedure through which temporal and spatial variations in data can be integrated into LCI files and then passed to …


A Comparison Of Optical Measurement Methods For The Growth Of S. Cerevisiae, Jackson Black May 2023

A Comparison Of Optical Measurement Methods For The Growth Of S. Cerevisiae, Jackson Black

Chemical Engineering Undergraduate Honors Theses

Genetic engineering of living organisms provides the opportunity to express and harvest different proteins from cell surfaces. Yeast (S. cerevisiae) is one such organism and is capable of being grown on an industrial scale. Cellular concentration is an important parameter to monitor while fermentation processes are underway, in order to control the environment inside the growth medium and maximize yields. Spectrophotometry is a conventional method for measuring concentration, but is limited by a narrow absorbance range, and the need for on-site periodic sampling. A continuous method of measurement, as provided by Bug Labs BE2100 non-invasive biomass monitor, would …


Measuring Plume Concentration Variations Under Neutral Atmospheric Conditions, Daniel Williams May 2023

Measuring Plume Concentration Variations Under Neutral Atmospheric Conditions, Daniel Williams

Chemical Engineering Undergraduate Honors Theses

Hazardous gases are increasingly becoming a large safety concern as the world continues to grow and industrialize. The modeling of when hazardous gases breach containment is an extremely important objective of consequence assessment planning and response. To improve the understanding of the variability inherent in passive gas releases, a test program to demonstrate the variability of gas concentration measurements at different location in a passive gas plume released from an area source in the ultra-low speed wind tunnel at the Chemical Hazards Research Center. A Flame Ionization Detector was used to measure the concentration of the source cloud. Methane was …


Interaction Effects And Selecting Regression Models Of Taylor Swift Song Popularity, Halle Schneidewind May 2023

Interaction Effects And Selecting Regression Models Of Taylor Swift Song Popularity, Halle Schneidewind

Industrial Engineering Undergraduate Honors Theses

Understanding music popularity and what drives it is important not only for artists but for other individuals who are financially tied to music sales including producers, writers, and record labels. Studies have been done to define how a song’s popularity can be measured, what attributes or features are drivers for popularity, and to what extent can a song’s popularity even be predicted. This paper takes two linear regression approaches to predicting the popularity of a Taylor Swift song on Spotify based on auditory features the Spotify API estimates and historic popularity of songs on Spotify. One model takes into consideration …


Lignin Copolymer Property Prediction Using Machine Learning, Collin Larsen May 2023

Lignin Copolymer Property Prediction Using Machine Learning, Collin Larsen

Chemical Engineering Undergraduate Honors Theses

Lignin, an abundant biopolymer, is a waste byproduct of the paper and pulp industry. Despite its renewable nature and potential applicability in various products, such as plastics and composites, the development of lignin-based materials has been impeded by the cumbersome, Edisonian process of trial and error. This research proposes a novel approach to forecasting the properties of lignin-based copolymers by utilizing a recurrent neural network (RNN) based on the Keras models previously created by Tao et al. Example units of modified lignin were synthesized via esterification and amination functional group modifications. To increase the efficiency and accuracy of the prediction …


Comprehensive Long- And Short- Read Sequencing Approaches To Screen The Mutational Landscape After Therapeutic Crispr-Editing For Duchenne Muscular Dystrophy, Mary Jia, Made Harumi Padmaswari, Landon Burcham, Shilpi Agrawal, Alexis Ivy, Abbey Bryan, Christopher E. Nelson May 2023

Comprehensive Long- And Short- Read Sequencing Approaches To Screen The Mutational Landscape After Therapeutic Crispr-Editing For Duchenne Muscular Dystrophy, Mary Jia, Made Harumi Padmaswari, Landon Burcham, Shilpi Agrawal, Alexis Ivy, Abbey Bryan, Christopher E. Nelson

Biomedical Engineering Undergraduate Honors Theses

Duchenne muscular dystrophy (DMD) is an X-linked muscle wasting disease caused by mutations in the Dmd gene resulting in non-functional dystrophin. Adeno-associated virus (AAV)-mediated delivery of classical CRISPR systems resulting in double-stranded breaks (DSBs) has yielded promise as a curative DMD therapeutic. However, the consequences of AAV-CRISPR require more thorough characterization. PCR-enriched short-read amplicon sequencing at cut sites is the most common method of sequencing CRISPR editing, but PCR bias results in unreliable quantification of on-target edits. We analyze orthogonal long- and short-read sequencing approaches to screen the outcomes of CRISPR technologies at the DNA and RNA-level for DMD. We …