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Exploring Ph Gradient Phenomena In Non-Linear Electrokinetic Microfluidic Devices, Azade Tahmasebi

Dissertations, Master's Theses and Master's Reports

Electrokinetic microfluidics is a versatile technology utilized within lab on a chip (LOC) devices for diagnostic and analytical applications; advantages include reduced resource demands, flexibility, and simplicity of use. Dielectrophoresis (DEP) is a precision nonlinear electrokinetic tool utilized within microfluidic microdevices to induce polarization and control bioparticle motions for applications that range from hemoglobin separations to cancer cell isolation and detection. Despite promising results, undesired side phenomena can occur in electrokinetic systems which impede reproducibility and accuracy. These unfavorable phenomena have not been comprehensively explored in the literature. Prior preliminary research suggests the fundamental phenomena originate from microelectrodes utilized in …

Why Representation Matters: Using Stem Education To Promote Opportunity, Sheramie Velazquez

Indiana STEM Education Conference

Research has highlighted how Black and Brown professionals continue to be underrepresented in the various science, technology, engineering and mathematics (STEM) fields. The lack of exposure to diverse STEM professionals, a challenging and relevant STEM curriculum, and belief in the brilliance of Black and Brown scholars’ abilities to succeed in STEM are vast contributors to the continual diversity underrepresentation in STEM-based classes and careers. Girls STEM Institute (GSI) was founded to create a space where girls of color-who are traditionally underrepresented in STEM-can become exposed to challenging and relevant STEM curricula, which is taught by diverse educators who share similar …

An Experimental Study On The Mechanical Properties And Chemical Composition Of Lcd 3d Printed Specimens, Sebastian Gomez

College of Graduate Studies: Theses & Dissertations

Additive manufacturing technologies have been enhanced throughout the years yet have surprised the manufacturing industry due to their high-end surface finish and dimensional accuracy. Different experiments have been done to identify a specific phenomenon known in the vat-polymerization field. Distortion and dimensional inaccuracy tend to affect the overall properties of the process, either physical or chemical. This approach allows the understanding of how the physical properties have been affected and how to study the chemical properties to avoid this type of phenomenon. The chemical reaction between polymer and UV light has been studied and experimented with to the point that …

Harnessing The Potential Of Fibrous Polyester Composites Meant For Bioactive Medical Devices, Graciela Morales, Heriberto Rodríguez-Tobías, Victoria Padilla-Gainza, Karen Lozano, Daniel Grande

Mechanical Engineering Faculty Publications

Fibrous-based composite polyester mats have gained importance in the biomedical area due to their morphological characteristics and mechanical performance. These materials can be modified by incorporating different inorganic micro- or nano-particles, thus leading to promising potential applications as medical devices with antimicrobial and/or bioactive properties. In this regard, this chapter reports a compilation of different studies related to the development of sub-micron fibers based on two important polyesters for biomedical use, namely poly(3-hydroxybutyrate) and poly(lactic acid). Studies focus on fibers developed through hydrodynamic techniques, namely electrospinning, electrospraying, and centrifugal spinning. The incorporation of zinc oxide or hydroxyapatite on the polyester-based …

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

McKelvey School of Engineering Graduate Student Theses & Dissertations

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

Fabrication And Characterization Of Force Spun Polymeric Nanofiber For Drug Delivery And Tissue Engineering Applications, Salahuddin Ahmed

Theses and Dissertations

This study focuses on the development and characterization of polymeric nanofiber for drug delivery and tissue engineering applications. In this study, poly(lactic-co-glycolic) acid (PLGA), Poly-vinyl alcohol (PVA), and Pullulan(PL) were used as the base polymers to develop the nanofiber. Bioactive components Oleanolic acid(OA), Oxymatrine(OM), and Salvianolic Acid(SA) were incorporated in PLGA, PVA, and PL, respectively, via solution mixing. The nano fiber systems were developed using the Forcespinning® method. Morphological, thermo-physical, and biological properties of the fiber mats were analyzed. The composite fiber system containing OA showed a very high drug loading efficiency. The composite fiber system containing high concentration of …

Development And Characterization Of Forcespinning® Mesquite Gum Nanofibers, Cristobal Rodriguez, Victoria Padilla, Karen Lozano, Alexa Villarreal, Luis A. Materon, Robert Gilkerson

Mechanical Engineering Faculty Publications

In this study, nanofibers incorporating Prosopis glandulosa mesquite gum (MG) exudate combined with biodegradable polymers, pullulan (PL) and chitosan (CH), were produced via the Forcespinning® technique. The nonwoven composite membranes were characterized via scanning electron microscopy followed by thermogravimetric and Fourier-transform infrared spectroscopy analysis. MG nanofiber composites comprised long, continuous fibers with an average fiber diameter of 523 ± 180 nm and 760 ± 225 nm for 18.1 and 28 wt% of MG, respectively. These composite membranes were water-stable after crosslinking via heat treatment with a ∼3 % water absorption capacity, and demonstrated a thermal capability with an increasing …

Importance Of Light Activation For Plant Cryptochrome And Antibacterial Drug Delivery Strategies, Merfat Ahmed Hammad

Theses and Dissertations

The goal of this project is to investigate the benefits of applying light in different systems. In the first part, the magnetoreception process that occurs in the light activated cryptochrome of Arabidopsis Thaliana was investigated. In the second part, photo-carbon monoxide releasing molecules (photo-CORMs) were investigated for their antibacterial effect to develop biomedical strategies. Overall, this has been achieved in three different studies. The first study investigated if the forward lightdriven reaction is involved in the magnetoreception process or not in cryptochrome (CRY). To accomplish this, the plant seedlings were tested for 90 minutes as follows: 5 minutes in the …

Digitally Predicting Protein Localization And Manipulating Protein Activity In Fluorescence Images Using 4d Reslicing Gan, Yang Jiao, Lingkun Gu, Yingtao Jiang, Mo Weng, Mei Yang

Electrical & Computer Engineering Faculty Research

While multi-channel fluorescence microscopy is a vital imaging method in biological studies, the number of channels that can be imaged simultaneously is limited by technical and hardware limitations such as emission spectra cross-talk. One solution is using deep neural networks to model the localization relationship between two proteins so that the localization of one protein can be digitally predicted. Furthermore, the input and predicted localization implicitly reflect the modeled relationship. Accordingly, observing the response of the prediction via manipulating input localization could provide an informative way to analyze the modeled relationships between the input and the predicted proteins.

A Nanofiber-Embedded Microfluidic Platform For Studying Neurobiology, Donghee Lee, Navatha Shree Sharma, S. M. Shatil Shahriar, Kai Yang, Zheng Yan, Jingwei Xie

Department of Mechanical and Materials Engineering: Faculty Publications

Due to their biomimetic properties, electrospun nanofibers have been widely used in neurobiology studies. However, mechanistic understanding of cell-nanofiber interactions is challenging based on the current in vitro culture systems due to the lack of control of spatiotemporal patterning of cells and difficulty in monitoring single cell behavior. To overcome these issues, we apply microfluidic technology in combination with electrospun nanofibers for in vitro studies of interactions between neurons and nanofiber materials. We demonstrate a unique nanofiber embedded microfluidic device which contains patterned aligned or random electrospun nanofibers as a new culture system. With this device, we test how different …

Calanoid Copepods Of China Seas-Introduction And Acknowledgement, Chang-Tai Shih, Qing-Chao Chen, Yang-Chi Lan, Shih-Hui Hsiao, Chi-Yu Weng

Journal of Marine Science and Technology–Taiwan

No abstract provided.

Advancing The Portability, Field Of View, And Spatiotemporal Resolution Of Multi-Parametric Photoacoustic Microscopy, Fenghe Zhong

McKelvey School of Engineering Graduate Student Theses & Dissertations

Capable of structural, functional, molecular, and metabolic imaging with high spatial resolution in vivo, photoacoustic microscopy (PAM) is an emerging tool in biomedical research. Further, recent advances in multi-parametric acquisition and analysis make PAM uniquely capable of simultaneously mapping the total concentration of hemoglobin (CHb), oxygen saturation of hemoglobin (sO2), and blood flow speed. However, there are multiple major limitations, including, the large footprint, low imaging speed, limited imaging contrast, and insufficient axial resolution, which impedance its applications in basic and translational research. In this dissertation, I presented potential solutions to overcome the limitations above.In the first part of this …

Biological Interaction Of Mn-Based Nanomaterials With Capsicum Annuum L. Under Salinity Stress, Yuqing Ye

Open Access Theses & Dissertations

The foliar application of nanomaterials as a method to overcome abiotic stress is relatively new compared to their use as fertilizers or pesticides in agricultural practice. It is also vital to understand the interface between leaf and nanomaterials, as nanomaterials might translocate into crop edible tissues, thus, causing potential toxicity in living beings during food consumption. In this dissertation, salt-stressed Capsicum annuum L was exposed to manganese (Mn) -based nanomaterials (Mn2O3 nanoparticles (MnNPs) and graphene quantum dots doped with Mn (GQD-Mn)) at different stages (seed germination and full life cycle). The dissertation focuses on investigating the mechanism of how Mn-based …

Multi-Dimensional Single-Molecule Nanoscopy: Fundamental Limits And Novel Approaches, Oumeng Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Single molecules (SMs) have become important tools for studying nanoscale dynamics in biological studies since they were first optically observed in 1989. Numerous techniques, termed single molecule orientation localization microscopy (SMOLM), have been developed to measure the position and orientation of SMs. Due to the challenging signal-to-background ratio (SBR) in typical SM experiments, it is critical to understand whether an imaging system is optimal for a specific target sample. However, the maximum theoretical limit of measurement performance has yet to be quantified. In Chapter 3. We first develop a mathematical framework to compute the accuracy limit in measuring the rotational …

The Development And Characterization Of Piezoelectric- Magnetostrictive Smart Self-Sensing Composites, George Relebohile Qhonosheane

Mechanical and Aerospace Engineering Dissertations - Archive

The composites industry is expanding due to the growing global demand for high-performance materials. How do you ensure the production of composites is as smooth and effective as possible while maintaining the high quality of the material? The key issues in composites include crack occurrence, sticking to molds in the production process, and durability differences during their operation. However, monitoring such cases can be challenging. The industry is in need of a smart solution to be able to obtain accurate data from the raw material. This work focuses on the development of smart composite materials. The word composite comes from …

Nonlinear Optical Microscopy Assessment Of Tissue Structure And Chondrocyte Viability Of Articular Cartilage, Michael Le

All Theses

Articular cartilage functions to protect the ends of bones by providing a surface that can withstand compressive forces and minimize friction during movement. Collagen fibers form the organizational backbone of the extracellular matrix (ECM) in cartilage. Proteoglycans within the ECM function to retain water and provide the tissue with the swelling pressure needed to withstand compressional forces. Chondrocytes, the only type of cell found in articular cartilage, produces these collagen fibers and proteoglycans to maintain the tissue structure and function. Significant injuries to articular cartilage can damage the chondrocytes and disrupt their ability to maintain homeostasis in the tissue. Therefore, …

Computer Vision And Machine Learning Applications In Cellular Images And Clinical Data, Guochang Ye

Theses and Dissertations

With the progressive development of artificial intelligence (AI), automated analysis has been explored for substituting tedious manual methods in cellular image analysis. Additionally, medical information not included in the conventional statistical methods is now being reconsidered with AI-based personalized medicine. The adaptivity and flexibility of AI ensure its efficiency and accuracy. In this work, computer vision and machine learning (ML) methods under the scope of AI are explicitly investigated and applied to cellular images and clinical data for cytological analysis and to provide diagnosis-based assistance/predictions. Firstly, novel computer vision algorithms achieve cell detection and differentiation estimation on phase-contact microscopic images …

Modeling And Analysis Of Subcellular Protein Localization In Hyper-Dimensional Fluorescent Microscopy Images Using Deep Learning Methods, Yang Jiao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hyper-dimensional images are informative and become increasingly common in biomedical research. However, the machine learning methods of studying and processing the hyper-dimensional images are underdeveloped. Most of the methods only model the mapping functions between input and output by focusing on the spatial relationship, whereas neglect the temporal and causal relationships. In many cases, the spatial, temporal, and causal relationships are correlated and become a relationship complex. Therefore, only modeling the spatial relationship may result in inaccurate mapping function modeling and lead to undesired output. Despite the importance, there are multiple challenges on modeling the relationship complex, including the model …

Development Of Zinc Oxide/Hydroxyapatite/Poly(D,L-Lactic Acid) Fibrous Scaffold For Tissue Engineering Applications, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Raúl Loera-Valencia, Cristóbal Rodríguez, Robert Gilkerson, Carlos Trevino De Leo, Karen Lozano

Mechanical Engineering Faculty Publications

Scaffolds based on polymeric fibers represent an engaging biomedical device due to their particular morphology and similarity with extracellular matrices. The biggest challenge to use fibrous materials in the biomedical field is related to their favorable platform for the adhesion of pathogenic microorganisms. Therefore, their optimum performance not only depends on their bioactive potential but also on their antimicrobial properties. The aim of this work was the design of antimicrobial (zinc oxide, ZnO) and bioactive (hydroxyapatite, Hap) fibrous materials using poly(D, L-lactic acid) (PDLLA) as the polymer fiber substrate. Fiber based composite scaffolds were developed using the Forcespinning® technique. For …

Mosquito Edge: An Edge-Intelligent Real-Time Mosquito Threat Prediction Using An Iot-Enabled Hardware System, Shyam Polineni, Om Shastri, Avi Bagchi, Govind Gnanakumar, Sujay Rasamsetti, Prabha Sundaravadivel

Electrical Engineering Faculty Publications and Presentations

Species distribution models (SDMs) that use climate variables to make binary predictions are effective tools for niche prediction in current and future climate scenarios. In this study, a Hutchinson hypervolume is defined with temperature, humidity, air pressure, precipitation, and cloud cover climate vectors collected from the National Oceanic and Atmospheric Administration (NOAA) that were matched to mosquito presence and absence points extracted from NASA's citizen science platform called GLOBE Observer and the National Ecological Observatory Network. An 86% accurate Random Forest model that operates on binary classification was created to predict mosquito threat. Given a location and date input, the …

The Photo-Transformation Of Free Methionine In The Presence Of Surrogate And Standard Isolate Dissolved Organic Matter Under Sunlit Irradiation, Benjamin J. Mohrhardt

Dissertations, Master's Theses and Master's Reports

Sulfur (S)-containing amino acids are key sources of carbon, nitrogen, and sulfur involved in protein synthesis, protein function, and providing energy for microbial growth. Dissolved free and combined methionine is one of two S-containing amino acids incorporated into proteins and has been attributed to their stability and function. The oxidation of methionine has received considerable attention given its ubiquitous presence in most biological systems and has been associated with losses in protein function and pathological disorders. In natural waters, methionine is rapidly and selectively taken up by microorganisms to achieve cellular requirements of carbon, nitrogen, and sulfur. The abiotic transformation …

A Hybrid Data And Hypothesis-Driven Model For Software Development In Support Of The Machine-Learning Paradigm, Anthony D. Bowman

All ETDs from UAB

istorically, research has often been conducted in a hypothesis-driven manner with software development methodologies created to support those efforts. However, in recent years data-driven approaches to research have seen a dramatic rise in prominence. While software development methodologies such as agile development, extreme programming, and the waterfall model have allowed developers to tackle increasingly complex problems, they were not designed to efficiently support data-driven approaches such as the machine learning paradigm. To address the need to support the different programmatic requirements of both classical, hypothesis-driven as well as data-driven development, novel development strategies are warranted. In this research, we adapted …

Pesticide Intoxication On Hepatic And Renal Functions Among Farmers In Nakhon Ratchasima, Thailand, Ekarat Sombatsawat

Chulalongkorn University Theses and Dissertations (Chula ETD)

In developing countries, pesticides are commonly used to protect crops and increase productivity among agricultural workers. These might cause effects to their health. The study aimed to compare the various variables between the pesticides unexposed and unexposed groups and find an association between pesticide intoxication on erythrocyte acetylcholinesterase (AChE), and hepatic and renal functions in farmers. A comparative cross-sectional study was conducted with 30 nonfarmers and 71 farmers during August to October 2022. Socio-demographic characteristics and variables related to pesticide exposure were collected using a questionnaire-based interview. The erythrocyte AChE inhibition, hepatic, and renal functions were measured by EQM Test-mate …

Algorithm Hardware Codesign For High Performance Neuromorphic Computing, Haowen Fang

Dissertations - ALL

Driven by the massive application of Internet of Things (IoT), embedded system and Cyber Physical System (CPS) etc., there is an increasing demand to apply machine intelligence on these power limited scenarios. Though deep learning has achieved impressive performance on various realistic and practical tasks such as anomaly detection, pattern recognition, machine vision etc., the ever-increasing computational complexity and model size of Deep Neural Networks (DNN) make it challenging to deploy them onto aforementioned scenarios where computation, memory and energy resource are all limited. Early studies show that biological systems' energy efficiency can be orders of magnitude higher than that …

Acoustic Radiation Force And Its Application For Cell Manipulation And Ion Channels Activation, Xiangjun Peng

McKelvey School of Engineering Graduate Student Theses & Dissertations

Sound is a stress wave that carries energy and momentum flux. Scattered sound waves can generate acoustic radiation force that can be used to manipulate particles or cells. This dissertation demonstrates the physics behind cell manipulation by ultrasound. The work begins with a detailed analysis of the mechanics of using standing surface acoustic waves to fabricate acoustic tweezers for contactless particle manipulation using acoustic radiation force. Models to design and analyze acoustic radiation force have traditionally relied on plane wave theories that cannot predict how standing surface acoustic waves can levitate cells in the direction perpendicular to the substrate. We …

Deep Learning For Automatic Microscopy Image Analysis, Shenghua He

McKelvey School of Engineering Graduate Student Theses & Dissertations

Microscopy imaging techniques allow for the creation of detailed images of cells (or nuclei) and have been widely employed for cell studies in biological research and disease diagnosis in clinic practices.Microscopy image analysis (MIA), with tasks of cell detection, cell classification, and cell counting, etc., can assist with the quantitative analysis of cells and provide useful information for a cellular-level understanding of biological activities and pathology. Manual MIA is tedious, time-consuming, prone to subject errors, and are not feasible for the high-throughput cell analysis process. Thus, automatic MIA methods can facilitate all kinds of biological studies and clinical tasks. Conventional …

Multi-Organs-On-Chips For Testing Small-Molecule Drugs: Challenges And Perspectives., Berivan Cecen, Christina Karavasili, Mubashir Nazir, Anant Bhusal, Elvan Dogan, Fatemeh Shahriyari, Sedef Tamburaci, Melda Buyukoz, Leyla Didem Kozaci, Amir K Miri

Henry M. Rowan College of Engineering Departmental Research

Organ-on-a-chip technology has been used in testing small-molecule drugs for screening potential therapeutics and regulatory protocols. The technology is expected to boost the development of novel therapies and accelerate the discovery of drug combinations in the coming years. This has led to the development of multi-organ-on-a-chip (MOC) for recapitulating various organs involved in the drug-body interactions. In this review, we discuss the current MOCs used in screening small-molecule drugs and then focus on the dynamic process of drug absorption, distribution, metabolism, and excretion. We also address appropriate materials used for MOCs at low cost and scale-up capacity suitable for high-performance …

Heteroacene-Based Amphiphile As A Molecular Scaffold For Bioimaging Probes, Tharindu A. Ranathunge, Mahesh Loku Yaddehige, Jordan H. Varma, Cameron Smith, Jay Nguyen, Iyanuoluwani Owolabi, Wojciech Kolodziejczyk, Nathan I. Hammer, Glake Hill, Alex Flynt, Davita L. Watkins

Faculty and Student Publications

The challenges faced with current fluorescence imaging agents have motivated us to study two nanostructures based on a hydrophobic dye, 6H-pyrrolo[3,2-b:4,5-b’]bis [1,4]benzothiazine (TRPZ). TRPZ is a heteroacene with a rigid, pi-conjugated structure, multiple reactive sites, and unique spectroscopic properties. Here we coupled TRPZ to a tert-butyl carbamate (BOC) protected 2,2-bis(hydroxymethyl)propanoic acid (bisMPA) dendron via azide-alkyne Huisgen cycloaddition. Deprotection of the protected amine groups on the dendron afforded a cationic terminated amphiphile, TRPZ-bisMPA. TRPZ-bisMPA was nanoprecipitated into water to obtain nanoparticles (NPs) with a hydrodynamic radius that was comparison, TRPZ-PG was encapsulated in pluronic-F127 (Mw = 12 kD), a polymer surfactant …

Wi-Fi-Based Indoor Localization Using Model-Based And Data-Driven Approaches, Ayoub Idelhaj

Electrical Engineering Theses - Archive

This thesis investigates model-based and data-driven approaches for indoor localization using the Received Signal Strength Indicator (RSSI) of Wi-Fi signals. We study multiple model-based indoor localization approaches, including the free space path loss model, the log-distance path loss model, the International Telecommunication Union (ITU) model, and a nonlinear regression model. We examine their indoor localization accuracy using raw RSSI values, and filter RSSI values passed through a Moving Average filter and a Kalman filter. For data driven approaches, we employ a family of Extreme Learning Machine (ELM) algorithms including Basic-ELM, Online Sequential-ELM (OS-ELM), Hierarchical-ELM (H-ELM), and Kernel-ELM (K-ELM), to find …

Controlled Reduction Of Graphene Oxide And Graphene Oxide-Carbon Nanotube Hybrids And Their Applications, Samar Azizighannad

Dissertations

Graphene and graphene derivatives are widely used in diverse research and industrial applications. Graphene production on a large scale is carried out by exfoliating graphite oxide and producing graphene oxide (GO), which comprises of graphene sheets with different oxygen-containing functional groups such as hydroxyl, carboxyl, and carbonyl. GO is reduced to reduced graphene oxide (rGO), which has properties that are closer to graphene. Properties of GO and rGO depend upon the oxygen content, and the effect of reducing oxygen content on the aqueous behavior of rGOs is not well understood.

In an effort to understand how properties of rGO change …