Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Georgia Southern University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 331 - 360 of 9181

Full-Text Articles in Entire DC Network

Assessment And Health Benefit Of Vitamin C Using A549 Cell, Yetunde Adepoju Jan 2025

Assessment And Health Benefit Of Vitamin C Using A549 Cell, Yetunde Adepoju

College of Graduate Studies: Theses & Dissertations

Vitamin C (ascorbic acid) is a vital micronutrient recognized for its antioxidant capacity and essential bodily functions, such as collagen formation, neurotransmitter activity, and regulation of the immune system. This study explores how vitamin C can protect and potentially heal cells under oxidative stress and inflammation, using A549 cells, a human lung epithelial cell line, as the model system. The cells were exposed to varying concentrations of vitamin C dissolved in water, DMSO, and 5% DMSO. To assess the outcome, cell viability was measured with an MTT assay. In addition, the expression of key genes related to oxidative stress and …


A Finite Volume-Based Approach For Modeling Hyperbaric Oxygen Therapy For Healing Chronic Wounds, Cade M. Layser Jan 2025

A Finite Volume-Based Approach For Modeling Hyperbaric Oxygen Therapy For Healing Chronic Wounds, Cade M. Layser

College of Graduate Studies: Theses & Dissertations

The current number of people in America with diabetes is approximately 38.4 million, that population is expected to rise to 54.9 million by 2030. Chronic wounds, which are characterized by impaired or stalled healing, are commonly associated with diabetes. These wounds if not treated properly can cause significant complications such as sepsis, infection, and gangrene which can lead to limb amputation or death of the patient. Limb amputations can be a large financial burden and significantly reduce the patient’s quality of life. The timely and efficient treatment of chronic wounds is essential to prevent adverse patient outcomes. Hyperbaric Oxygen therapy …


Defect Detection In Extrusion-Based Bio-Printed Constructs Using Video-Based Vibration Analysis, Md Anisur Rahman Jan 2025

Defect Detection In Extrusion-Based Bio-Printed Constructs Using Video-Based Vibration Analysis, Md Anisur Rahman

College of Graduate Studies: Theses & Dissertations

Bio-additive manufacturing has emerged as a transformative advancement in biomedical engineering, enabling the fabrication of complex biological structures. However, maintaining the precision and quality of printed constructs remains a significant challenge, particularly in applications such as bioprinted organ transplants. Among the key factors affecting structural integrity, dimensional inconsistencies and interlayer defects present major obstacles, potentially compromising mechanical stability and functionality. This study explores the detection of defects caused by variations in dimensional accuracy and layer-to-layer adhesion. To address these challenges, a video-based motion estimation technique is employed as a non-contact and non-destructive evaluation method. Traditional approaches, such as contact-based and …


Synthesis And Processing Of Co-Axial/Tri-Axial Multi-Layered Nano-Particles, Jannatul Ferdaus Jan 2025

Synthesis And Processing Of Co-Axial/Tri-Axial Multi-Layered Nano-Particles, Jannatul Ferdaus

College of Graduate Studies: Theses & Dissertations

Electro-spraying has been used as an effective processing method of nanoparticle fabrication for the application of targeted drug delivery. The study demonstrates the feasibility of a non-conventional triaxial electro-spraying setup for multi-layered nano-drug fabrication and proposes optimized parameters. Two different drugs, XAV939 and Dextran 40000, were used to study the process parameters (voltage and solution concentration) of coaxial electro spraying. The particle size of Dextran-PCL was an average of 166.3 nm for PCL-Dextran at 32.5 kV and 18-hour sonication. The SEM analysis and UV-spectrum showed the encapsulation of Dextran with PCL, though the in vitro study in mice after 24 …


Long-Term Ichthyoplankton Monitoring Of The Moon River (Savannah, Ga) With A Focus On Climate Change, Bradley Cayson Jan 2025

Long-Term Ichthyoplankton Monitoring Of The Moon River (Savannah, Ga) With A Focus On Climate Change, Bradley Cayson

College of Graduate Studies: Theses & Dissertations

The presence of healthy fish populations is a cornerstone of many important ecological mechanisms. These populations are supported by the recruitment of ichthyoplankton, or the egg and larval stages of fishes, as the primary determinant of population growth. Increases in average global water temperatures can alter the composition of fish communities and thus the offspring found in planktonic stages. I compared a large data set of ichthyoplankton surveys completed from 2009-2011 to a replicated six-month sampling period from May – November of 2024. Collection was conducted weekly to biweekly during night flood tides using a fixed suspension ichthyoplankton net (1mm …


Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun Jan 2025

Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun

College of Graduate Studies: Theses & Dissertations

Coastal ecosystems provide critical carbon sequestration services, yet the microbial mechanisms underlying carbon storage remain poorly understood, particularly in non-vegetated habitats. This study investigated whether restored oyster reefs (Crassostrea virginica) enhance sediment carbon storage potential by stabilizing microbial communities and promoting efficient organic matter processing. I hypothesized that reef-mediated sediment stabilization and organic deposition would create conditions favoring microbial degradation of complex carbon compounds into stable soil organic matter, ultimately supporting anaerobic carbon storage. To test this, I compared sediment biogeochemistry, enzyme activity, and microbial community structure between three restored oyster reef sites and two unstructured control sites …


Multiphysics Modeling Of Solid Oxide Fuel Cells For Gradient Minimization And Inductive Loop Analysis In Impedance Spectroscopy Using Machine Learning-Based Microstructural Property Estimation, Muhammad Usman Khan Jan 2025

Multiphysics Modeling Of Solid Oxide Fuel Cells For Gradient Minimization And Inductive Loop Analysis In Impedance Spectroscopy Using Machine Learning-Based Microstructural Property Estimation, Muhammad Usman Khan

College of Graduate Studies: Theses & Dissertations

Solid oxide fuel cells have significant advantages in renewable energy utilization due to their high efficiency, fuel flexibility, and low emissions. However, despite the numerous efforts of technology, thermal and current density gradients and impedance behavior fluctuations are still causing performance degradation. A combined computational framework that integrates machine learning and three-dimensional Multiphysics modeling is needed to investigate and optimize the performance of solid oxide fuel cells. A machine learning model, trained on synthetic microstructure data by percolation analysis, is used to predict important microstructural parameters like triple phase boundary density and geometric tortuosity. These are then employed in a …


The School Of Becoming: Speculative Essays On Existential Possibility And Humanity In Education, Timothy A. Holman Jan 2025

The School Of Becoming: Speculative Essays On Existential Possibility And Humanity In Education, Timothy A. Holman

College of Graduate Studies: Theses & Dissertations

This dissertation reimagines public education through an existential lens, advocating for a humanitarian approach that resists the prevailing dominance of standardized, data-driven systems. Drawing primarily from the philosophy of Jean-Paul Sartre (1936, 1940, 1943, 1947, 1965, 1992), it contends that education should honor freedom, nurture authenticity, embrace encounters with others, and cultivate imagination as essential to human development. Influenced by the works of William Ayers (1998, 2004, 2008, 2016, 2024), Maxine Greene (1967, 1973, 1978, 1988, 2000, 2001), Paulo Freire (1970, 2001, 2004), Christopher Emdin (2010, 2016, 2021), and Byung-Chul Han (2018, 2024), speculative essays—each focused on an existential theme—are …


A Phenomenological Study Exploring The Lived Experiences Of First-Generation African American Students To Improve Retention Rates, Jaleesa Porter Jan 2025

A Phenomenological Study Exploring The Lived Experiences Of First-Generation African American Students To Improve Retention Rates, Jaleesa Porter

College of Graduate Studies: Theses & Dissertations

Colleges and universities play an important role in maintaining high retention rates and getting students from matriculation to graduation. There are several studies related to the reasons and barriers that result in low retention rates. This qualitative study examined how one university in southeast Georgia can improve retention rates among first-generation African American students by enhancing its practices. The findings from this study the revealed lived experiences of college students that resulted in a range of emotions, resources and barriers, and communication. Discussion and implications of the findings provide recommendations for practice and future research.


Experimental Study Of Deformation Behavior For A Novel Elastohydrodynamic Seal For Supercritical Carbon Dioxide Power Cycles, William A. Adams Jan 2025

Experimental Study Of Deformation Behavior For A Novel Elastohydrodynamic Seal For Supercritical Carbon Dioxide Power Cycles, William A. Adams

College of Graduate Studies: Theses & Dissertations

Supercritical carbon dioxide (sCO2) Brayton cycles are a strong contender for future power generation systems due to their high thermal efficiency and compact nature. Sealing is one of the key challenges presented by such systems that has a direct impact on the system's overall efficiency. This research is the first experimental study to investigate the deformation behavior of an elastohydrodynamic (EHD) seal made from bearing-grade polyether ether ketone (PEEK). A testing apparatus was developed to integrate four strain gauges positioned along the seal to quantify the deformation occurring up to pressures of 13 MPa. Mass flow rate measurements …


One-Dimensional Numerical Analysis Of A Novel Elastohydrodynamic Seal For Supercritical Co2 Power Cycles With Experimental Validation And Future Approach, Cole B. Hayne Jan 2025

One-Dimensional Numerical Analysis Of A Novel Elastohydrodynamic Seal For Supercritical Co2 Power Cycles With Experimental Validation And Future Approach, Cole B. Hayne

College of Graduate Studies: Theses & Dissertations

This thesis presents a numerical analysis and experimental verification approach for a novel elastohydrodynamic (EHD) seal designed with the specific application of supercritical carbon dioxide (sCO2) power cycles. Brayton power cycles with sCO2 as the working fluid have gained significant traction as potential large-scale power generation methods. This increase in interest and research is primarily due to their many beneficial characteristics, such as high thermal efficiency, compact geographic footprint, reduced capital costs, and lower water and fuel usage than comparable power cycles. Despite these many positive qualities, proper sealing technology remains one of the primary barriers to …


Viscoelastic Property Analysis Of A Magnetorheological Elastomer Micropump For Insulin Delivery In Type 1 Diabetes, Victor Buitimea Jan 2025

Viscoelastic Property Analysis Of A Magnetorheological Elastomer Micropump For Insulin Delivery In Type 1 Diabetes, Victor Buitimea

College of Graduate Studies: Theses & Dissertations

Over two decades, there has been a significant rise in awareness regarding Type 1 Diabetes (T1D), leading to a deeper comprehension of numerous variables, including hereditary factors, patterns of occurrence, and health challenges. According to the Type 1 Diabetic Index, around 8.7 million people worldwide are affected by this chronic autoimmune illness marked by a lack of insulin and hyperglycemia. The introduction of artificial pancreas systems could save more than half a million patients by 2040. Despite the availability of various insulin delivery technologies that are offered to diabetic patients, many still are skeptical of this modern system. The issues …


Computational Investigation Of Underbody Slant Angle Variation Effect On A Hatchback Vehicle, Nufile Uddin Ahmed Jan 2025

Computational Investigation Of Underbody Slant Angle Variation Effect On A Hatchback Vehicle, Nufile Uddin Ahmed

College of Graduate Studies: Theses & Dissertations

Electric Vehicles, despite many advantages over their gasoline-powered counterparts, have the following main challenges towards mass adoption – the charging infrastructure and the range of the vehicle. Among the myriads of factors affecting the range, the coefficient of drag and the required power to overcome it are noteworthy. This study aims to investigate the effect of rear underbody slant angle on a common, simplified hatchback-shaped Electric Vehicle. The rear underbody slant angles (upward) assessed were 0°, 5°, 10°, and 15° and they were subjected to three freestream velocities representative of urban (16 m/s), highway (25 m/s) and interstate (40 m/s) …


Machine Learning For Automated Classification Of Tree Species Based On Color-Texture Fusion, Brandon C. Jones Jan 2025

Machine Learning For Automated Classification Of Tree Species Based On Color-Texture Fusion, Brandon C. Jones

College of Graduate Studies: Theses & Dissertations

This study aimed to develop robust machine learning tools for the classification of southeastern United States tree species based on bark images, addressing challenges posed by significant intraspecies variation in bark texture and color. The primary objectives included constructing specialized machine learning libraries and classification models, identifying optimal algorithms and parameters to maximize accuracy, and integrating the best-performing texture and color classifiers into a unified system to enhance the overall classification performance. The methodology involved collecting a dataset of 360 field images, extracting hue and saturation histograms for color features, and employing Histogram of Gradients (HOG) and Histogram of Binary …


An Investigative Study Of Thermal Fluid Properties When Introducing Metallic Nanoparticles Through A Heat Exchanging System, Levi P. Mckinney Jan 2025

An Investigative Study Of Thermal Fluid Properties When Introducing Metallic Nanoparticles Through A Heat Exchanging System, Levi P. Mckinney

College of Graduate Studies: Theses & Dissertations

Heat-exchanging systems are essential in applications ranging from automobiles to air-conditioning units, and ongoing improvements aim to enhance efficiency while reducing system size. Conventional coolant upgrades often rely on ethylene glycol, which increases thermal stability and lowers freezing point but reduces water’s inherent heat-transfer capability. Advances in nanotechnology provide an alternative approach: suspending nanoparticles in base fluids can significantly modify thermal properties, with some formulations exhibiting conductivity increases of up to 60%. This thesis examines the thermal and tribological performance of three working fluids—distilled water, a 50:50 water–ethylene glycol mixture, and the same mixture enhanced with Al₂O₃ nanoparticles. Distilled water …


Evaluating Spatiotemporal Vegetation Index Variation To Detect Salt Marsh Dieback On The Georgia Coast, Emmanuella Bosompemaa Obeng Jan 2025

Evaluating Spatiotemporal Vegetation Index Variation To Detect Salt Marsh Dieback On The Georgia Coast, Emmanuella Bosompemaa Obeng

College of Graduate Studies: Theses & Dissertations

Salt marshes, essential for coastal protection and carbon sequestration, are increasingly vulnerable to dieback events, threatening ecosystem resilience and vital services. Detecting these shifts early is essential for timely intervention. However, few studies have applied Early Warning Signals (EWS) to coastal marsh systems. Most EWS research has focused on lakes, forests, or climate tipping points, with limited application to salt marsh dieback in the southeastern U.S. Site-specific, long-term spatial analyses are also lacking, as prior work often examines short time frames or single disturbance events. This study investigates the spatiotemporal patterns of salt marsh dieback on the Georgia coast from …


Synthesis And Assessment Of Biobased Acrylated Epoxidized Soybean Oil Resins For Stereolithography 3d Printing Of Microfluidic Devices, Natalie S. Romero Figueroa Jan 2025

Synthesis And Assessment Of Biobased Acrylated Epoxidized Soybean Oil Resins For Stereolithography 3d Printing Of Microfluidic Devices, Natalie S. Romero Figueroa

College of Graduate Studies: Theses & Dissertations

This research focuses on the development and characterization of a biobased photocurable resin synthesized from soybean oil for use in stereolithography (SLA) 3D printing of microfluidic devices. The study explores a sustainable alternative to petroleum-based resins by performing an acrylation reaction on epoxidized soybean oil (ESO) to produce acrylated epoxidized soybean oil (AESO), which was then formulated into a photocurable resin with the addition of a photo initiator. The fabrication process involved designing microfluidic molds in SolidWorks and printing them using an Elegoo Mars 4 SLA printer under various exposure and layer thickness parameters. The printed samples consisted of microchannels …


Effect Of Alloying Additions On Austenite Refinement In Nickel-Alloyed Ductile Cast Irons, Adnan Adib Aahamed Jan 2025

Effect Of Alloying Additions On Austenite Refinement In Nickel-Alloyed Ductile Cast Irons, Adnan Adib Aahamed

College of Graduate Studies: Theses & Dissertations

The benefits associated with the application of ductile irons are significantly attributed to the control of microstructures, with refinement of austenitic matrix during solidification playing a significant role. Nickel alloyed ductile irons are attractive due to their potential for high ductility and suitability for potential high-temperature applications with stable austenitic microstructure. Refinement of austenite grain structure is thus important to enhance the mechanical properties of the alloyed ductile iron. This research investigates the impact of in-mold additions of different alloying elements on the austenite morphology and grain refinement of nickel-alloyed ductile iron along with the associated mechanical properties. A hypoeutectic …


Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker Jan 2025

Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker

College of Graduate Studies: Theses & Dissertations

This study seeks to investigate a testing methodology that utilizes accelerated testing methods (ATM) in conjunction with nondestructive testing methods (NDT) to assess destructive ion attacks on concrete. Through the testing of concrete samples, the impacts of chloride and sulfate ions on concrete will be tested by subjecting concrete to cyclic testing in an artificial climate environment. Electrical resistivity (ER) and ultrasonic pulse velocity (UPV) testing will evaluate the impact of the accelerated testing on the migration of destructive ions within the pore structure of the tested concrete. Based on this investigation, comparisons between accelerated, non-accelerated, and control samples will …


Evaluating The Effectiveness Of Lidar And Photogrammetry For Inspecting Mse Walls In Bridges, Shakil Ahmed Jan 2025

Evaluating The Effectiveness Of Lidar And Photogrammetry For Inspecting Mse Walls In Bridges, Shakil Ahmed

College of Graduate Studies: Theses & Dissertations

Mechanically Stabilized Earth (MSE) retaining walls are vital components of transportation infrastructure, providing structural support for embankments and bridge approaches. As many walls approach or exceed their design life, concerns regarding long-term stability, settlement, and displacement have increased. Traditional visual inspection remains the most common assessment method; however, it is subjective and often unable to detect subtle geometric changes that may precede structural distress or failure. This study evaluates Terrestrial LiDAR (Light Detection and Ranging) Scanning (TLS) and Close-Range Photogrammetry (CRP) as nondestructive, noncontact alternatives for detecting displacement in MSE retaining walls. Three representative sites were investigated: a Control Wall …


Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu Jan 2025

Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu

College of Graduate Studies: Theses & Dissertations


Abstract

This research explores the development of bio resin from linseed oil by the process of epoxidation and acrylation to produce acrylated epoxidized linseed oil (AELO). Lignin and cellulose biopolymers were added as reinforcement at varying weight fractions of 1 wt.%, 2.5 wt.%, and 5 wt.%, and their mechanical performance was compared against pure AELO. The formulations were printed using an Elegoo SLA 3D printer to create standardized test specimens like tensile bars, compression cylinders, and hardness blocks, which were all prepared according to the ASTM testing standard.

The results indicate that reinforcement effects depend on both filler type and …


Hybrid Rans-Les Analysis Of Turbulent Flame Under Near Blow-Off Condition In A Multi-Stage Swirl Combustor, Brandon O'Brien Jan 2025

Hybrid Rans-Les Analysis Of Turbulent Flame Under Near Blow-Off Condition In A Multi-Stage Swirl Combustor, Brandon O'Brien

College of Graduate Studies: Theses & Dissertations

Advances in computational resources are making computational fluid dynamics (CFD) increasingly accessible for a variety of engineering applications. However, certain complex problems, such as simulating detailed flame kinetics, remain computationally prohibitive for many users. Developing cost-effective methods to simulate these challenges would greatly benefit applications involving flame dynamics, such as turbine engines or industrial burners. This study investigates the effect of main stage swirler intensity on near lean blow-off characteristics in a multi-staged swirl combustor using Ansys Fluent. The hybrid RANS-LES turbulence model, Stress Blended Eddy Simulation (SBES) coupled with Flamelet Generated Manifold (FGM) combustion model was selected to model …


Understanding The Opioid Crisis In Georgia: A County-Level And Racial Equity Analysis, Lillian C. Fealy, Gulzar H. Shah Jan 2025

Understanding The Opioid Crisis In Georgia: A County-Level And Racial Equity Analysis, Lillian C. Fealy, Gulzar H. Shah

Eagles Talking About the Public’s Health

No abstract provided.


Ambulatory Care Sensitive Conditions And Alzheimer’S Discharge In Georgia's Older Population, Anjana Kalathimekkattu, Gulzar H. Shah Jan 2025

Ambulatory Care Sensitive Conditions And Alzheimer’S Discharge In Georgia's Older Population, Anjana Kalathimekkattu, Gulzar H. Shah

Eagles Talking About the Public’s Health

No abstract provided.


2025 Fall Commencement, Georgia Southern University Jan 2025

2025 Fall Commencement, Georgia Southern University

Commencement Programs

No abstract provided.


2025 Spring Commencement, Georgia Southern University Jan 2025

2025 Spring Commencement, Georgia Southern University

Commencement Programs

No abstract provided.


Faculty Handbook, Georgia Southern University Jan 2025

Faculty Handbook, Georgia Southern University

Faculty Handbooks

Faculty Handbook for Georgia Southern University for the 2024-2025 academic year. The Faculty Handbook is published online by the Office of the Vice President for Academic Affairs and archived in Digital Commons@Georgia Southern.


2025 Georgia Southern University Men's Soccer Roster, Georgia Southern University Jan 2025

2025 Georgia Southern University Men's Soccer Roster, Georgia Southern University

Men's Soccer Records

No abstract provided.


2025 Georgia Southern University Women's Soccer Media Guide, Georgia Southern University Jan 2025

2025 Georgia Southern University Women's Soccer Media Guide, Georgia Southern University

Women's Soccer Records

No abstract provided.


2024-2025 Georgia Southern University Women's Swimming And Diving Roster, Georgia Southern University Jan 2025

2024-2025 Georgia Southern University Women's Swimming And Diving Roster, Georgia Southern University

Women's Swimming Records

No abstract provided.