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The Antioxidant Potential Of Rosemary Leaf-Derived Nanovesicles, Shani Akila Griffin

Master's Theses

Human dermal fibroblasts are essential for maintaining skin homeostasis. However, exposure to exogenous and endogenous stressors can lead to fibroblast instability, extracellular matrix degradation, and excessive reactive oxygen species (ROS) production. These factors contribute to skin aging and ROS-induced skin disorders leading to hair loss. Adverse effects from synthetic treatments have driven interest in natural alternatives like plant extracts for skin therapy. However, the polyphenols in these treatments require an effective delivery system to ensure their stability and targeted application. Plant derived nanovesicles (PDNVs) are emerging as a promising natural alternative for therapeutic applications. Their biocompatibility, stability, and encapsulated compounds …

Skin Cancer Diagnosis Utilizing Hybrid Discrete Cosine Transform And High-Performance Convolutional Neural Networks, Mohammed M. Abo-Zahhad, Mohammed Abo-Zahhad

Mansoura Engineering Journal

Detecting skin cancer early and accurately is crucial for successfully treating this potentially fatal disease. Enhancing the accuracy of visual inspection techniques is often necessary to improve clinical decision-making and increase the chance of successful treatment outcomes. In this research, high-performance deep learning (DL) models for automated skin cancer categorization and early skin cancer diagnosis screening are developed and evaluated in conjunction with the discrete cosine transform (DCT). For this purpose, features are extracted from medical images using both techniques. The DCT is used for feature extraction and dimensionality reduction, while deep learning (DL) trains fully connected models for classification …

Engineering The Immune Response To Biomaterials, Abolfazl Salehi Moghaddam, Mehran Bahrami, Einollah Sarikhani, Rumeysa Tutar, Yavuz Nuri Ertas, Faleh Tamimi, Ali Hedayatnia, Clotilde Jugie, Houman Savoji, Asma Talib Qureshi, Muhammad Rizwan, Chima V. Maduka, Nureddin Ashammakhi

Michigan Tech Publications

Biomaterials are increasingly used as implants in the body, but they often elicit tissue reactions due to the immune system recognizing them as foreign bodies. These reactions typically involve the activation of innate immunity and the initiation of an inflammatory response, which can persist as chronic inflammation, causing implant failure. To reduce these risks, various strategies have been developed to modify the material composition, surface characteristics, or mechanical properties of biomaterials. Moreover, bioactive materials have emerged as a new class of biomaterials that can induce desirable tissue responses and form a strong bond between the implant and the host tissue. …

Predicting Seizure Onset Zones From Interictal Intracranial Eeg Using Functional Connectivity And Machine Learning, Jared Pilet, Scott A. Beardsley, Chad Carlson, Christopher T. Anderson, Candida Ustine, Sean Lew, Wade Mueller, Manoj Raghavan

Biomedical Engineering Faculty Research and Publications

Functional connectivity (FC) analyses of intracranial EEG (iEEG) signals can potentially improve the mapping of epileptic networks in drug-resistant focal epilepsy. However, it remains unclear whether FC-based metrics provide additional value beyond established epilepsy biomarkers such as epileptic spikes and high-frequency oscillations (HFOs). Using interictal iEEG data from 26 patients, we estimated FC across eight frequency bands (4–290 Hz) using amplitude envelope correlation (AEC) and phase locking value (PLV). From the resulting FC-matrices, we estimated two graph metrics each to derive 32 FC-based features. We also extracted features related to spikes, HFOs, and power spectral densities (PSD). A trained support …

Evaluation Of Schoenoplectus Californicus In An Artificial System For E. Coli Removal, Kimia Ahmadiyehyazdi

Masters Theses (Archived)

Green technologies and nature-based solutions like constructed wetlands have be come more popular due to their environmentally friendly approach to remediation, low cost of construction, and maintenance. Also, they have shown efficiency in removing a wide range of contaminants. However, choosing a suitable aquatic plant for this system is one of the questions that should be answered wisely. Schoenoplectus californicus– Giant Bulrush is an aquatic plant that was tested in this controlled constructed wetland, and the final concentration of the targeted microbial contamination, which is E. coli, was reduced remarkably. Also, for this study, soil was removed from the …

Functionalizing Polyethersulfone Membranes: Using Nmr To Avoid Pitfalls When Using Uv-Induced Polymerization To 'Graft From' Surfaces, Priyanka Suresh, Megan M. Sibley, Amy C. Che, Christine E. Duval

Faculty Scholarship

For nearly 30 years, UV-induced free radical polymerization has been used to modify the surface chemistry of polyethersulfone (PES) membranes, films, and coatings. The initial mechanism for the grafting process was introduced in the 1990s and supported without direct evidence of covalent bond formation. Since then, claims of ‘grafting from’ membranes in the literature rely on similar evidence using a combination of gravimetry, attenuated total reflectance infrared spectroscopy, contact angle goniometry, water sorption, and/or water permeance. While these techniques provide evidence of the presence of a polymer coating, they do not provide direct evidence of covalent bond formation between the …

Predicting Strut Geometry Of Pcl And Dmso2 Biocomposites From Nozzle To Deposition In Bio-Scaffold 3d Printing, Jae-Won Jang, Kyung-Eun Min, Jun-Hee Park, Cheolhee Kim, Sung Yi

Mechanical and Materials Engineering Faculty Publications and Presentations

The field of tissue engineering increasingly demands accurate predictive models to optimize the 3D printing process of bio-scaffolds. This study presents a unified numerical model that predicts extrusion velocity and strut diameter based on printing conditions and the material properties of polycaprolactone (PCL) and dimethyl sulfone (DMSO2) composites. The extrusion velocity was simulated using Navier–Stokes equations, while the strut diameter was calculated via a surface energy model. For PCL, the extrusion velocity showed a temperature coefficient of 23.3%/°C and a pressure coefficient of 19.1% per 100 kPa; the strut diameter exhibited a temperature coefficient of 21.6%/°C and a pressure coefficient …

Sustainability In The Cruising Industry: Innovations In Air Quality, Energy Efficiency, And Waste Management, Fikret Durmus, Mi Ran Kim

ICHRIE Research Reports

The cruise industry, a cornerstone of the global hospitality and tourism sector, faces increasing scrutiny over its environmental impact. As passenger numbers grow, so does the industry's responsibility to adopt sustainable practices. This report examines key innovations in air quality management, energy efficiency, and waste management, highlighting the industry's transition from historically high emissions and waste production to advanced sustainability initiatives. Key focus areas include evolving maritime regulations, adopting cleaner propulsion technologies, integrating energy-efficient solutions, and improving waste treatment practices. Findings indicate that industry leaders are investing in liquefied natural gas engines, exhaust gas cleaning systems, and onshore power supply …

Development And Evaluation Of A Simple Human Body Link Model Considering The Degrees-Of-Freedom Of Shoulders, Mizuki Takeda, Yuki Saito, Kaiji Sato

Progress in Scale Modeling, an International Journal

Modeling of the human body is widely utilized in the field of human–robot interaction, warranting the development of a simple model to measure and recognize the human body movements. To this end, a two-dimensional (2D) human body link model in the sagittal plane has been used to represent the human body with rotating joints and links connecting these joints. The joint positions can be determined by using the coordinates of a limited number of points on the links and estimated using a few sensor outputs when the links are of constant length. However, models with constant link lengths may result …

A Review Of Direct Ink Writing Of Polymer Derived Ceramics, Victoria Bishop, Saket Chand Mathur, Nhu Nguyen, Bhisham Sharma, Mary Drouin, Bin Li, Cheol Park, Wei Wei

Michigan Tech Publications

With the growing demand for materials capable of withstanding extreme temperatures and pressures, ceramic components with exceptional corrosion resistance and reliable mechanical properties have experienced a significant surge in demand. However, traditional ceramic forming methods involve high-temperatures and energy-intensive processes that often struggle to produce complex parts or composites efficiently. Polymer-Derived Ceramics (PDCs) offer a transformative solution by using polymeric precursors that can be converted into a wide variety of silicon-based and non-silicon-based ceramics through heat treatment. The polymeric nature of PDC precursors enables the fabrication of geometrically intricate components using conventional polymer-forming techniques at significantly lower processing temperatures. Furthermore, …

The Rapid Detection Of Foreign Fibers In Seed Cotton Based On Hyperspectral Band Selection And A Lightweight Neural Network, Yeqi Fei, Zhenye Li, Dongyi Wang, Chao Ni

Biological and Agricultural Engineering Faculty Publications and Presentations

Contamination with foreign fibers-such as mulch films and polypropylene strands-during cotton harvesting and processing severely compromises fiber quality. The traditional detection methods often fail to identify fine impurities under visible light, while full-spectrum hyperspectral imaging (HSI) techniques-despite their effectiveness-tend to be prohibitively expensive and computationally intensive. Specifically, the vast amount of redundant spectral information in full-spectrum HSI escalates both the system's costs and processing challenges. To address these challenges, this study presents an intelligent detection framework that integrates optimized spectral band selection with a lightweight neural network. A novel hybrid Harris Hawks-Whale Optimization Operator (HWOO) is employed to isolate 12 …

A Highly Sensitive Electrochemical Immunosensor For Cortisol Detection, Pritu Sarkar, Ali Ashraf, Ahmed Hasnain Jalal, Fahmida Alam, Nazmul Islam

Mechanical Engineering Faculty Publications

In this research, an interdigitated gear-shaped working electrode is presented for cortisol sensing. Overall, the sensor was designed in a three-electrode system and was fabricated using direct laser scribing. A synthesized conductive ink based on graphene and polyaniline was further employed to enhance the electrochemical performance of the sensor. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were employed for physicochemical characterization of the laser-induced graphene (LIG) sensor. Cortisol, a biomarker essential in detecting stress, was detected both in phosphate-buffered saline (PBS, pH = 7.4) and human serum within a linear range of 100 ng/mL to 100 µg/mL. …

Aerial Robotic Studies Of Volcanic Co2 Emissions, John Ericksen

Computer Science ETDs

Volcanic systems are inherently complex, involving dynamic interactions among magma flow, gas emissions, and atmospheric dispersion. This dissertation focuses on developing and analyzing autonomous UAS algorithms for efficiently surveying volcanic CO2 plumes, introducing several novel methods: the LoCUS algorithm, a swarm coordination and self-healing algorithm that supports gradient-based plume tracking, a transect-based technique that employs a 2D Gaussian fit to calculate CO2 plume flux, and the Sketch algorithm for rapid plume boundary tracing. By treating multiple UAS as a single scientific instrument, these methods leverage swarm algorithms to use in-situ data in ways impossible with individual drones. Validated through simulations …

An Overview Of Global Navigation Satellite System Reflectometry In Coastal Wetlands, Luke Andrew Redwine

Theses and Dissertations

With rising global temperatures, increasing sea levels, and the accelerated erosion of coastal wetlands, efficient methods for monitoring this vulnerable ecosystem are crucial. Traditional approaches, such as manual surveys, are labor-intensive, hazardous, and invasive to the environment they are attempting to protect, while current remote sensing methods are cost prohibitive and rely on irregular data collection techniques. To address these challenges, a scalable solution is needed for reliable and frequent data collection. This study explores the use of GNSS Reflectometry (GNSS-R) combined with unmanned aerial vehicles (UAVs) to monitor the shifting topology in wetlands with minimal human invasion. By leveraging …

Zn–Assisted Synthesis Of M (Mn/Fe/Co/Ni)-N-C Catalysts For Multifunctional Electrochemical Activity, Kemila A. Chaudhary

Electronic Theses & Dissertations

The design and development of atomically dispersed M-N-C catalysts (metal (M) supported on an nitrogen-carbon (NC) matrix with high multifunctional electrocatalytic performance is desirable but proved to be very challenging. Herein, we synthesized M-N-C catalysts (M = Fe, Co, Mn, and Ni) using Zn-assisted high temperature treatment and characterized using various techniques. The prepared catalysts were tested for their electrocatalytic performance towards oxygen and hydrogen evolution reaction (OER and HER) as well as oxygen reduction reaction (ORR) in alkaline media. The results indicated that Mn-N-C catalyst showed higher performance towards both the ORR (E_1/2 = 0.90 V) and …

Investigating Structure-Property Relationships Of Bio-Inspired Gel, Mohammad Moinul Hossain

Theses and Dissertations

High-modulus, stretchable, and resilient hydrogels possess a wide array of promising applications across multiple fields, such as the development of sophisticated prosthetic devices, artificial skin, electronic devices, and soft robotics. Elastomeric biopolymers, like resilin, show high stretchability and resilience, facilitating power-amplified movement in various species essential for feeding and defense mechanisms. To mimic the properties of resilin, we developed a hydrogel system of hydrophobic and hydrophilic components. These gels are synthesized by free radical polymerization of acrylic acid (AAc), methacrylamide (MAM), n-tert-beutylacrylamide (BAM) or n-isopropylacrylamide (NIPAM), and poly (propylene glycol) diacrylate (PPGDA). This research aims to compare the large-strain mechanical …

Wildfire Hydrologic Impacts, Kathleen E. Inman

Theses and Dissertations

Wildfires are essential processes for certain ecosystems but are increasing in severity and occurrence. These increases are negatively changing hydrology. Anticipating the hydrologic changes is necessary for management of effected watersheds, infrastructure, and downstream users. This study hypothesized land cover changes post-fire would increase water temperature and discharge in burned watersheds located in the Willamette Basin. This study (1) evaluated the change in estimated curve numbers (CN) from land cover pre-fire and post-fire to assess expected runoff impacts in watersheds, and (2) identified the significance of actual water temperature and discharge changes using non-parametric statistical analysis. An unburned watershed and …

Finite Element Analysis Of Hydroxyapatite (Ha) Coated Porous We43 Magnesium Scaffolds For Simulating Long-Time In Vitro Degradation Using A Continuum Damage Model, Dam Kim

Theses and Dissertations

While magnesium and its alloys are viable biodegradable implant candidates for its similarity of Young’s modulus with human bone and its strong biocompatibility, a pure magnesium scaffold degrades too rapidly to be used in many orthopedic implications. Overcoming this high degradation rate has been one of the biggest technical challenges for Mg-based biomedical applications. This research focuses on validating a finite element analysis framework using a continuum damage model and its application to simulate the degradation process of non-coated additively manufactured WE43 and HA-coated WE43 magnesium scaffolds. This work includes determining model input parameters by matching in vitro experiment results …

An In Depth Examination Of Educational, Family, Economic, And Personal Determinants On Academic Performance, Engagement, And Stress: A Comprehensive Study Among Engineering Students, Oumaima Larif

Theses and Dissertations

This study explores the effects of family, education, economic, and personal factors on students’ decisions to pursue engineering as a profession and their long-term impact on performance as engineering students. We adopted a mixed-method approach, collecting data through surveys administered to undergraduate and graduate engineering students at Mississippi State University. The study results revealed that family, education, economic, and personal factors profoundly influence students' decisions to study engineering. We found that parental expectations, background information, and socioeconomic status, in conjunction with cultural norms, values, gender expectations, and religious beliefs, affect students. Additionally, this study identified gaps in the existing literature …

Removal Of Harmful Algal Bloom Toxin, Microcystin-Lr Via Graphene Coated Polymers, Justin Douglas Puhnaty

Theses and Dissertations

This study investigates a novel 3D-printed graphene-coated polymer (GCP) for the removal of Microcystin-LR (MC-LR), a harmful cyanotoxin produced during harmful algal blooms (HABs). While graphene nanoplatelets (GnPs) exhibit high adsorption capacity, their powdered form limits practical application. To address this, GnPs were coated onto 3D-printed poly(lactic acid) (PLA) substrates, enabling enhanced handling for field deployment. Surface characterization using laser confocal microscopy, Raman spectroscopy, and thermogravimetric analysis confirmed GnP distribution and coating uniformity. Batch adsorption experiments revealed pseudo-second-order kinetics, a maximum adsorption capacity (qmax) of 596 μg/g, and adsorption behavior best described by the Langmuir isotherm. Statistical analysis and comparison …

Instability-Driven Phase Separation For Quantum Structure Formation In Iii-V Semiconductors, Leonid Miroshnik

Chemical and Biological Engineering ETDs

High temperature phase instability limits the performance of III-V zinc blende semiconductor devices. A technique using an encapsulant and sacrificial layer is developed to reduce thermal degradation by group V sublimation during thermal processing of InGaAs/GaAs structures. This technique is successful in preventing As sublimation and preserving an atomically smooth surface required for surface-sensitive characterization. The degradation of the GaAsSb/InP interface by phase separation is studied. Significant interdiffusion and intermixing occurs due to the formation of a molten InSb at the interface. The intermixing is driven by phase separation and melting of the InSb interfacial layer that enhances atomic mobility. …

El, A Navigational Assistant Based Upon Echolocation, Arthur Mazer

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis investigates the integration of a parametric speaker with a microphone array to enhance the echolocation of objects. A parametric speaker focuses ultrasonic and audible waves in a specified direction. This endows the parametric speaker with the capacity to focus waves across a wide frequency spectrum enabling adaptation of the frequency to environmental considerations.Beam forming allows one to focus a microphone array in a specified direction. The thesis investigates different microphone array configurations for the purpose of enhancing the echolocation ability of an echolocation device. The primary goal of the thesis is the construction and testing of an echolocation …

Analysis Of Incident Duration And Real-Time Incident Delay Estimation Using Big Data Analytics And Machine Learning Techniques, Zhubin Najafi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traffic incidents have a significant impact on freeway operations, leading to severe delays, congestion, fuel wastage, and economic losses for commuters. Each year, billions of gallons of fuel are wasted, and drivers incur thousands of dollars in lost time due to incident-related delays. To mitigate these effects, Traffic Management Centers (TMCs) implement incident management strategies aimed at reducing both the frequency and severity of incidents while ensuring their prompt and safe clearance.

Dynamic Message Signs (DMSs) are key tools used by TMCs to communicate travel times and incident information to commuters. Under normal conditions, default travel times are displayed on …

Developments On Abbreviations Towards Machine Reading Comprehension, Sing Choi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Machine reading comprehension is a critical step in development of applications that require the semantic understanding of human speech-to-text driven work. Many devices such as smart home appliances like the Amazon Echo Dot, Google Home, or smart assistants like Apple Siri or Microsoft Cortana are examples of these applications. The comprehension task involves a deeper understanding and recognition of named entities such as person names, locations, medicals codes, quantities, abbreviations, and acronyms in speech or text data. In this dissertation, we explore and extend the different approaches and techniques in modern research that tackles the problem of recognition and definition …

Real-World Implementation Of A Noninvasive, Ai-Augmented, Anemia-Screening Smartphone App And Personalization For Hemoglobin Level Self-Monitoring, Robert G. Mannino, Julie Sullivan, Jennifer K. Frediani, Paul George, Jeremy Whitson, James Tumlin, L. Andrew Lyon, Erika A. Tyburski, Wilbur A. Lam

Engineering Faculty Articles and Research

Anemia, characterized by low blood hemoglobin (Hgb) levels, afflicts >2 billion individuals worldwide. Here, we report real-world data generated by a smartphone app that noninvasively screens for anemia using only “fingernail selfies.” App data for anemia screening were obtained from >1.4 million uses across the United States enabling geographic mapping of Hgb levels. Of those, 9,061 users also self-reported complete blood count Hgb levels for comparison, resulting in accuracy and performance that match gold standard laboratory testing and a sensitivity and specificity of 89% and 93%, respectively, when using an anemia cutoff of 12.5 g/dL. Geotagged data enabled construction of …

Reconfiguration-Driven Assembly Of Inorganic Nanomembranes, Divya Jyoti Prakash

Chemical and Biological Engineering ETDs

This thesis focuses on the guided self-assembly of metastable nanomembranes (NMs) that are either amorphous or polycrystalline. Guided self-assembly of NMs is a robust and scalable method to obtain a variety of three-dimensional structures such as helices, rolled-up tubes, and networks of interconnected channels. These 3D structures have important applications as on-chip actuators, sensors, inductors, transformers, waveguides, and antennas. Furthermore, a large amount of strain and strain gradient can be imparted in NMs by bending them to a nanoscale and microscale radius of curvature, making guided self-assembly on NMs a viable route to extreme strain engineering of amorphous and polycrystalline …

Development Of A Light-Based Platform To Assess Cervical Mucus Barrier Function And Physical Mucus Properties, Elizabeth J. Buzbee

McKelvey School of Engineering Graduate Student Theses & Dissertations

Preterm birth is the leading cause of neonatal morbidity and mortality worldwide, yet current clinical tools for predicting its risk lack specificity and reliability. Cervical mucus plays a crucial role in maintaining pregnancy by forming a barrier that protects the uterus against infection. This study investigates the use of laser speckle rheology as a noninvasive technique to assess cervical mucus biomechanics. Synthetic cervical mucus was fabricated at varying hydration levels and tested using a conventional rheometer that confirmed that the mechanical properties of the synthetic mucus samples were representative of physiological cervical mucus. These results were compared to the complex …

Impact Of Prior Exposures On Biomarkers Of Blast During Military Tactical Training, Zhaoyu Wang, Shengnan Sun, Alis Aksar Kranfli, Jeffrey Nemes, Molly J. Sullan, Andrew J. Hoisington, Lisa A. Brenner, Miciej Skotak, Christina R. Lavalle, Yongchao Ge, Walter Carr, Fatemah Haghighi

Faculty Publications

Blast injuries and subclinical effects are of significant concern among those Service Members (SMs) participating in military operations and tactical trainings. Studies of SMs repeatedly exposed during training find concussion-like symptomology with transient decrements in neurocognitive performance, and alterations in blood biomarkers. How prior mild TBI (mTBI) history interacts with low-level blast (LLB) exposure, however, remains unexplored, which we investigate in the present study, to identify interindividual biomarker changes from LLB exposures influenced by prior history of mTBI.

In-Silico Investigation Of Claudin-16 Self Assembly In Tight Junctions, Baqi Ozomata Atimah

Theses - ALL

Claudin-16 is a member of the Claudin family of proteins, which play a critical role in establishing paracellular permeability within tight junctions between cells. Claudin-16 exhibits diverse properties related to ion selectivity, tissue development, and barrier function. Depending on the context, claudins create channels that permit the passage of specific ions through the paracellular space or form barriers that restrict ion movement. This study focuses on the self-assembly of the human claudin-16 protein, which is essential for ion reabsorption and the proper functioning of the kidney. Molecular simulations were employed to investigate the interactions within dimerized claudin-16 and to elucidate …

Understanding Shell Adhesion Mechanics For Soft Gripper Design, Chenxu Zhao

Dissertations - ALL

This dissertation investigates the adhesion mechanics of hyperelastic hemispherical shells with finite thicknesses undergoing large deformation against rigid planar substrates. By integrating theoretical modeling, numerical simulations, and experimental validation, a comprehensive understanding of the adherence-detachment behavior of soft elastomeric shell structures is established. The study also applies these insights to the design of soft robotic grippers based on tunable adhesion. To understand the dry adhesion of a free soft shell against a rigid substrate, first, a graphical-numerical modeling framework based on the energy approach is developed and used to predict shell adhesion with a wide range of surface energy, thickness, …