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Soft Electronics And Sensors For Wearable Healthcare Applications, Li-Wei Lo Aug 2022

Soft Electronics And Sensors For Wearable Healthcare Applications, Li-Wei Lo

McKelvey School of Engineering Graduate Student Theses & Dissertations

Wearable electronics are becoming increasingly essential to personalized medicine by collecting and analyzing massive amounts of biological signals from internal organs, muscles, and blood vessels. Conventional rigid electronics may lead to motion artifacts and errors in collected data due to the mismatches in mechanical properties between human skin. Instead, soft wearable electronics provide a better platform and interface that can form intimate contact and conformably adapt to human skin. In this respect, this thesis focuses on new materials formulation, fabrication, characterization of low-cost, high sensitivity and reliable sensors for wearable health monitoring applications.

More specifically, we have studied the silver …


Machine Learning And Scalable Informatics Methods To Predict Disease Status From Multimodal Biomedical Data, Hossein Mohammadian Foroushani Aug 2022

Machine Learning And Scalable Informatics Methods To Predict Disease Status From Multimodal Biomedical Data, Hossein Mohammadian Foroushani

McKelvey School of Engineering Graduate Student Theses & Dissertations

Biological understanding of complex diseases such as stroke and obesity is critical for the advancement of medicine. Further knowledge discovery can provide effective biomarkers to improve disease diagnosis and prognosis, identify driver mutations, predict individual genetic susceptibility for early prevention and effective disease management, and facilitate development of personalized drugs. Stroke is the second leading cause of death and long-term disability in the world. Thus, stroke management is a time-sensitive emergency. The initial hours after stroke onset map the trajectory of subsequent neurologic complications. Cerebral edema develops hours to days after acute ischemic stroke and may result in midline shift …


Evaluation And Clinical Implementation Of A Dual-Energy Ct Stopping-Power Ratio Mapping Technique For Proton-Therapy Treatment Planning, Maria Jose Medrano Matamoros Aug 2022

Evaluation And Clinical Implementation Of A Dual-Energy Ct Stopping-Power Ratio Mapping Technique For Proton-Therapy Treatment Planning, Maria Jose Medrano Matamoros

McKelvey School of Engineering Graduate Student Theses & Dissertations

Proton radiotherapy has the potential to treat tumors with better conformal dose distribution than competing modalities when the rapid dose falloff at the end of the proton-beam range is correctly aligned to the edge of the clinical target volume (CTV). However, its clinical potential is dependent on the accurate localization of the Bragg-peak position from predicted stopping-power ratio maps. The method that is most commonly used in today’s clinical practice for predicting stopping-power ratio (SPR) consists of a stoichiometric calibrationtechnique based on single-energy CT (SECT) for direct estimation of patient-specific SPR distribution from vendor-reconstructed Hounsfield Unit (HU) images. Unfortunately, this …


Ligand- And Strain-Specific Control Of Microbial Communities, Austin Grant Rottinghaus Aug 2022

Ligand- And Strain-Specific Control Of Microbial Communities, Austin Grant Rottinghaus

McKelvey School of Engineering Graduate Student Theses & Dissertations

Microbes naturally coexist in complex, multi-strain communities that are valuable assets for their host. Commensal and probiotic microbes prevent pathogen colonization, reduce the frequency and severity of various ailments, provide essential nutrients, and offer various additional benefits. Understanding the dynamics of and tailoring microbial communities to provide additional beneficial functions is a primary focus of researchers in medicine and agriculture. To date, consortia have primarily been manipulated by supplementing the communities with microbes that were engineered in vitro or by introducing stimuli that alter the metabolism or composition of the community. This method has proven successful, with numerous microbes engineered …


Droplet Dynamics And Heat Transfer During Condensation On Lubricant-Infused Surfaces, Jianxing Sun Aug 2022

Droplet Dynamics And Heat Transfer During Condensation On Lubricant-Infused Surfaces, Jianxing Sun

McKelvey School of Engineering Graduate Student Theses & Dissertations

Inspired by pitcher plants, a micro/nano- structured solid surface infused with low-surface-tension lubricant constitutes a novel class of biomimetic surfaces—lubricant-infused surfaces (LISs). Unlike solid hydrophobic and superhydrophobic surfaces, a LIS is “hemi-solid and hemi-liquid”. The thin lubricating film can extraordinarily decrease adhesion and avoid contact line pinning between the working fluid and the underlying solid, displaying many desirable properties, such as excellent liquid repellency, suppression of fouling, and self-healing. Hence, LISs are ideal for applications where liquids or contaminants must be efficiently removed from surfaces in harsh environments. For example, LISs can promote stable dropwise condensation of water or low-surface-tension …


Calcium Bearing Mineral-Hydrogel Composites For Phosphate Removal And Recovery, Albern Xuan-Wei Tan Aug 2022

Calcium Bearing Mineral-Hydrogel Composites For Phosphate Removal And Recovery, Albern Xuan-Wei Tan

McKelvey School of Engineering Graduate Student Theses & Dissertations

The millions of tons of phosphate rock ore mined every year for use as phosphorus fertilizer have created two challenges. First, phosphate rock is a mined, non-renewable resource that is also heavily geographically concentrated, raising concerns about the long-term sustainability and availability of phosphorus. Second, after it is applied as a fertilizer, phosphorus will also be released to the broader environment. There, it contributes to harmful algal blooms and eutrophication, which threaten surface water quality and can harm aquatic ecosystems and the communities and industries that rely on them. These considerations motivate the coupled development of techniques for removing and …


Modeling, Analysis, And Simulation To Reveal The Mechanisms Of Ciliary Beating, Louis Woodhams Aug 2022

Modeling, Analysis, And Simulation To Reveal The Mechanisms Of Ciliary Beating, Louis Woodhams

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cilia are microscopic cellular appendages that help us breathe by clearing our airways, maintain the health of our central nervous system by circulating cerebrospinal fluid, and allow us to reproduce by transporting eggs and propelling sperm cells. Cilia even determine the asymmetry of our internal organs during embryonic development. However, the mechanisms underlying ciliary beating are not fully understood. Questions remain as to how arrays of the motor protein dynein generate the propulsive waveforms observed in cilia and how structural elements within the cilium and its connection to the cell deform during beating. In the current work, mathematical modeling, analysis, …


Noninvasive Neuromodulation Via Ultrasonic Activation Of Endogenous And Exogenous Ion Channels, Yaoheng Yang Aug 2022

Noninvasive Neuromodulation Via Ultrasonic Activation Of Endogenous And Exogenous Ion Channels, Yaoheng Yang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Neuromodulation technology is key to understanding brain function and treating brain diseases. Conventional neuromodulation technologies, such as direct current stimulation, transcranial magnetic stimulation, and optogenetics, predominately rely on electromagnetic waves. However, the fundamental physical law  the tradeoff-relationship between penetration and spatial resolution, limits their transcranial penetration within the superficial cortex layer. To overcome this challenge, electrodes or optical fibers need to be surgically implanted into the brain to modulate specific brain regions. Different from electromagnetic waves, ultrasound, as a mechanical wave, can non-invasively penetrate through the intact skull to reach deep brain regions with millimeter spatial focus. Ultrasound has …


Advancing The Portability, Field Of View, And Spatiotemporal Resolution Of Multi-Parametric Photoacoustic Microscopy, Fenghe Zhong Aug 2022

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 …


The Generation And Transport Of Charged Aerosols: Fundamental Study And Applications In Medicine And Energy Conversion, Hao Zhou Aug 2022

The Generation And Transport Of Charged Aerosols: Fundamental Study And Applications In Medicine And Energy Conversion, Hao Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

Charged aerosols have significant implications in the field of functional material synthesis, pharmaceutical coating, and drug delivery. Electrospray systems are an effective methodology for generating highly charged monodispersed droplets in the size range from nanometer to micrometer. The prediction of surface charge, size and morphology of nanoparticles resulting from charged droplets are highly required for the precise control of nanoparticle properties and their effective utilization. However, the evolution of charged droplet is not well understood due to the existence of coulombic fission and ion evaporation processes. Thus, the goal of this dissertation is to elucidate how the precursor properties and …


Thermomagnetic-Responsive Self-Folding Microgrippers For Improving Minimally Invasive Surgical Techniques And Biopsies, Caleigh R. Dunn, Bruce Lee, Rupak Rajachar Aug 2022

Thermomagnetic-Responsive Self-Folding Microgrippers For Improving Minimally Invasive Surgical Techniques And Biopsies, Caleigh R. Dunn, Bruce Lee, Rupak Rajachar

Michigan Tech Publications, Part 1

Traditional open surgery complications are typically due to trauma caused by accessing the procedural site rather than the procedure itself. Minimally invasive surgery allows for fewer complications as microdevices operate through small incisions or natural orifices. However, current minimally invasive tools typically have restricted maneuverability, accessibility, and positional control of microdevices. Thermomagnetic-responsive microgrippers are microscopic multi-fingered devices that respond to temperature changes due to the presence of thermal-responsive polymers. Polymeric devices, made of poly(N-isopropylacrylamide-co-acrylic acid) (pNIPAM-AAc) and polypropylene fumarate (PPF), self-fold due to swelling and contracting of the hydrogel layer. In comparison, soft metallic devices feature a pre-stressed metal bilayer …


Nanoscale Interfacial Control Of Ion Behaviors And Caco3 Formation In Environmental Systems, Yaguang Zhu Aug 2022

Nanoscale Interfacial Control Of Ion Behaviors And Caco3 Formation In Environmental Systems, Yaguang Zhu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Interfaces in environmental systems can change the distribution of pollutants and nutrients, determine the fate and transport of nanoparticles, and affect the efficiency of engineering projects. Complex interactions, including electrostatic interactions, Van der Waals interactions, chemical interactions, and ion-surface specific interactions, can all contribute to different ion, ion-pair, and nanoparticle formations near interfaces. Although environmental interfaces play critical roles, only a limited number of studies have considered the nanoscale picture of how they control ions and nanoparticles. Thus, this dissertation addresses three research questions: (1) How does sulfate chemically interact with calcium carbonate (CaCO3) during its heterogeneous formation on quartz …


Using Heritage Sites At Bahariya Oasis On The Tourism Urban Development, Medhat Ahmed Shabaan Samra Aug 2022

Using Heritage Sites At Bahariya Oasis On The Tourism Urban Development, Medhat Ahmed Shabaan Samra

Mansoura Engineering Journal

Throughout the tourism planning process for the Bahariya Oasis area, the current study aims to prepare this area to become an applicable model that converts the values of cultural heritage resources into economic values within the tourism industry and the establishment of tourism projects in this area. The Bahariya Oasis area is characterized by many Valuable regions that have not been included on the tourism map by the Egyptian government. To achieve those objectives, the researcher adopted the 'Analytic-Descriptive Approach', as it is suitable for this study throughout reviewing the literature related to the research subject, describing the current situation, …


Labeling Melanoma Cells With Black Microspheres For Improved Sensitivity In Detection Via Photoacoustic Flow Cytometry, Tori Kocsis Aug 2022

Labeling Melanoma Cells With Black Microspheres For Improved Sensitivity In Detection Via Photoacoustic Flow Cytometry, Tori Kocsis

Electronic Theses and Dissertations

Melanoma is an aggressive form of skin cancer known for developing into metastatic disease. Current clinical diagnostics, including medical imaging and tissue biopsy, provide a poor prognosis since the cancer is in the late stages of disease progression. In recent years, photoacoustic flow cytometry has allowed for the detection of circulating melanoma cells within patient blood samples in vitro. Although this method exploits the naturally-produced melanin within the cells, it has only successfully detected highly-pigmented melanoma cell lines. Since various forms of melanoma exist, each with varying melanin concentrations, this research aims to provide a novel method for detecting lightly-pigmented …


Nonordered Dendritic Mesoporous Silica Nanoparticles As Promising Platforms For Advanced Methods Of Diagnosis And Therapies, S. Malekmohammadi, Riaz Ur Rehman Mohammed, H. Samadian, A. Zarebkohan, A. García-Fernández, G. R. Kokil, F. Sharifi, J. Esmaeili, M. Bhia, M. Razavi, M. Bodaghi, T. Kumeria, R. Martínez-Máñez Aug 2022

Nonordered Dendritic Mesoporous Silica Nanoparticles As Promising Platforms For Advanced Methods Of Diagnosis And Therapies, S. Malekmohammadi, Riaz Ur Rehman Mohammed, H. Samadian, A. Zarebkohan, A. García-Fernández, G. R. Kokil, F. Sharifi, J. Esmaeili, M. Bhia, M. Razavi, M. Bodaghi, T. Kumeria, R. Martínez-Máñez

Department of Chemical and Biomolecular Engineering: Faculty Publications

Dendritic mesoporous silica nanoparticles (DMSNs) are a new generation of porous materials that have gained great attention compared to other mesoporous silicas due to attractive properties, including straightforward synthesis methods, modular surface chemistry, high surface area, tunable pore size, chemical inertness, particle size distribution, excellent biocompatibility, biodegradability, and high pore volume compared with conventional mesoporous materials. The last years have witnessed a blooming growth of the extensive utilization of DMSNs as an efficient platform in a broad spectrum of biomedical and industrial applications, such as catalysis, energy harvesting, biosensing, drug/gene delivery, imaging, theranostics, and tissue engineering. DMSNs are considered great …


System Dynamics Modeling For Traumatic Brain Injury: Mini-Review Of Applications, Erin S. Kenzie, Elle L. Parks, Nancy Carney, Wayne Wakeland Aug 2022

System Dynamics Modeling For Traumatic Brain Injury: Mini-Review Of Applications, Erin S. Kenzie, Elle L. Parks, Nancy Carney, Wayne Wakeland

Complex Systems Faculty Publications and Presentations

Traumatic brain injury (TBI) is a highly complex phenomenon involving a cascade of disruptions across biomechanical, neurochemical, neurological, cognitive, emotional, and social systems. Researchers and clinicians urgently need a rigorous conceptualization of brain injury that encompasses nonlinear and mutually causal relations among the factors involved, as well as sources of individual variation in recovery trajectories. System dynamics, an approach from systems science, has been used for decades in fields such as management and ecology to model nonlinear feedback dynamics in complex systems. In this mini-review, we summarize some recent uses of this approach to better understand acute injury mechanisms, recovery …


Liquid-Phase Effects On Adsorption Processes In Heterogeneous Catalysis, Mehdi Zare, Mohammad S. Saleheen, Nirala Singh, Mark J. Uline, Muhammad Faheem, Andreas Heyden Aug 2022

Liquid-Phase Effects On Adsorption Processes In Heterogeneous Catalysis, Mehdi Zare, Mohammad S. Saleheen, Nirala Singh, Mark J. Uline, Muhammad Faheem, Andreas Heyden

Faculty Publications

Aqueous solvation free energies of adsorption have recently been measured for phenol adsorption on Pt(111). Endergonic solvent effects of ∼1 eV suggest solvents dramatically influence a metal catalyst's activity with significant implications for the catalyst design. However, measurements are indirect and involve adsorption isotherm models, which potentially reduces the reliability of the extracted energy values. Computational, implicit solvation models predict exergonic solvation effects for phenol adsorption, failing to agree with measurements even qualitatively. In this study, an explicit, hybrid quantum mechanical/molecular mechanical approach for computing solvation free energies of adsorption is developed, solvation free energies of phenol adsorption are computed, …


A Spatial Long-Term Trend Analysis Of Estimated Chlorophyll-A Concentrations In Utah Lake Using Earth Observation Data, Kaylee Brook Tanner Aug 2022

A Spatial Long-Term Trend Analysis Of Estimated Chlorophyll-A Concentrations In Utah Lake Using Earth Observation Data, Kaylee Brook Tanner

Theses and Dissertations

We analyzed chlorophyll-a (chl-a) concentrations in shallow, turbid Utah Lake using Landsat data from 1984 to 2021. Utah Lake is ~40 km by 21 km, has a surface area of ~390 km2, an average depth of ~3 m, and loses ~50% of inflow to evaporation. This limits spatial mixing, allowing us to evaluate impacts to smaller lake regions. We evaluated long-term trends at the pixel level and for areas related to boundary conditions. We created 17 study areas based on differences in shoreline development and nutrient inflows. We expected impacted areas to exhibit increasing chl-a trends, as population growth and …


Novel 3d Bench Top Model For Vascular Calcification Research, Ursla-Marie K. Offiah Aug 2022

Novel 3d Bench Top Model For Vascular Calcification Research, Ursla-Marie K. Offiah

Theses and Dissertations

Cardiovascular disease is the leading cause of non-communicable disease in the whole world killing 17 million people in 2012. Among the many vascular diseases is vascular calcification (VC) which is the mineral build up in the walls of blood vessels. Medial calcification is the plaque buildup in the medial layer of the blood vesicle that is characterized by arterial stiffness and high blood pressure. Current calcification research involves two dimensional (2D) lab methods such as flat petri dishes to investigate the mechanism that causes and inhibits vascular calcification. Research has shown that the use of three-dimensional (3D) models can be …


Experiments To Mitigate Flow Recirculation In A Closed Anechoic Chamber Using Mesh Screens As Turbulence Suppressors, Tori Kay Wolverton Aug 2022

Experiments To Mitigate Flow Recirculation In A Closed Anechoic Chamber Using Mesh Screens As Turbulence Suppressors, Tori Kay Wolverton

Theses and Dissertations

The desire to gather acoustic data of a propeller in simulated hover without environmental effects is met with the challenge of recirculating flow in a closed anechoic chamber. Flow recirculation in an anechoic chamber is not ideal because the effects of it being ingested by the rotor cause unsteady loadings on the propeller. This unsteady loading causes vortex noise from the turbulence introduced by the recirculation of the flow. The aim is to study the acoustic signature of a propeller separate from external factors and engine noise. Two different propellers with three different screen combinations were tested in a closed …


Bayesian Network Development For Depots Location Selection With Biomass Supply System Excellence, Alaa Ashraf Abulhamail Aug 2022

Bayesian Network Development For Depots Location Selection With Biomass Supply System Excellence, Alaa Ashraf Abulhamail

Theses and Dissertations

The renewable energy of the wood pellet market has taken great attention over the last few periods. However, the returns from the pellet business depend largely on how well the quality of biomass. The objective is to economically harvest pellets matching pellet standards set forward by the U.S. markets. The single-mindedness of this study is to develop a Bayesian network model to ensure a high-quality flow through the supply chain of the pallet industry in the top ten counties in Mississippi state. Multiple critical decisions (harvesting, storage, transportation, and quality control) of a biomass-to-pellet supply system could potentially affect the …


Behavioral And Histological Inflammatory Analysis Of A Single, Mild Traumatic Brain Injury And Repeated Subconcussive Brain Injury Using A Rodent Model., Anna Marie Clay Aug 2022

Behavioral And Histological Inflammatory Analysis Of A Single, Mild Traumatic Brain Injury And Repeated Subconcussive Brain Injury Using A Rodent Model., Anna Marie Clay

Theses and Dissertations

Subconcussive (SC) impacts have become a growing concern within the neuroscience community regarding the immediate and long-lasting effects of sports-related injuries. While a single low-level impact, i.e., a subconcussion, may not cause cerebral perturbations, it has been increasingly recognized that repeated SC exposure can induce deleterious effects. Therefore, determining the lower limits of systematic perturbation resulting from multiple SC impacts is of critical importance in expanding our understanding of cerebral vulnerability and recovery. Currently, there is a lack of correlation between a mild traumatic brain injury (mTBI) and repeated SC impacts with respect to injury biomechanics. Moreover, the cumulative threshold …


Evaluation Of Flood Damage On Cross Laminated Timber Wall Configurations, Mustafa Nezih Kaya Aug 2022

Evaluation Of Flood Damage On Cross Laminated Timber Wall Configurations, Mustafa Nezih Kaya

Theses and Dissertations

Greenhouse gas emissions are one of the critical factors that affect climate change, increasing flooding risk and threatening human life. The use of traditional construction materials is responsible for a higher percentage of global greenhouse gas emissions when compared to the use of sustainable materials in the construction industry. The substitution of current building materials with sustainable materials is essential to reduce greenhouse gas emissions and positively influence climate change when the current construction demand in the world is considered. Wood is one of the primary environmentally friendly construction materials in regard to high carbon storage and low carbon emissions. …


Economic And Hydraulic Simulation Models For Evaluation Of Sediment Management In A Reservoir, Razieh Anari Aug 2022

Economic And Hydraulic Simulation Models For Evaluation Of Sediment Management In A Reservoir, Razieh Anari

Theses and Dissertations

Reservoir sedimentation is a serious problem that threatens the water storage capacities across the world. Extending a dam's life requires adopting a new design and operational paradigm that focuses on managing the reservoir and watershed system to bring sediment inflow and outflow into balance by including reservoir sediment management facilities in dam and reservoir. However, the cost of methods that remove the sediment from reservoirs is usually prohibitive and is a serious factor preventing sustainable sediment management. This thesis considered a case study, Paonia Reservoir in Colorado, to investigate two aspects of reservoir operation, sediment management and economic assessment. The …


Team Building Without Boundaries, Andy Perkins, Joan Peckham, Tayo Obafemi-Ajayi, Xiuzhen Huang Aug 2022

Team Building Without Boundaries, Andy Perkins, Joan Peckham, Tayo Obafemi-Ajayi, Xiuzhen Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Team building can be challenging when participants are from the same discipline or sub-discipline, but needs special attention when participants use a different vocabulary and have different cultural views on what constitutes viable problems and solutions. Essential to No Boundary Thinking (NBT) teams is proper formulation of the problem to be solved, and a basic tenant is that the NBT team must come together with diverse perspectives to decide the problem before solutions can be considered. Given that participants come with different views on problem formulation and solution, it is important to consider a robust process for team formation and …


Nbt (No-Boundary Thinking): Needed To Attend To Ethical Implications Of Data And Ai, Joan Peckham, Andy Perkins, Tayo Obafemi-Ajayi, Xiuzhen Huang Aug 2022

Nbt (No-Boundary Thinking): Needed To Attend To Ethical Implications Of Data And Ai, Joan Peckham, Andy Perkins, Tayo Obafemi-Ajayi, Xiuzhen Huang

Electrical and Computer Engineering Faculty Research & Creative Works

In this era of Big Data and AI, expertise in multiple aspects of data, computing, and the domains of application is needed. This calls for teams of experts with different training and perspectives. Because data analysis can have serious ethical implications, it is important that these teams are well and deeply integrated. No-Boundary Thinking (NBT) teams can provide support for team formation and maintenance, thereby attending to the many dimensions of the ethics of data and analysis. In this NBT workshop session, we discuss the ethical concerns that arise from the use of data and AI, and the implications for …


Ultraviolet Chiral Plasmonics, Tiago Ramos Leite Da Silva Aug 2022

Ultraviolet Chiral Plasmonics, Tiago Ramos Leite Da Silva

LSU Doctoral Dissertations

The far- (λ < 250 nm) ultraviolet (UV) chiroptical response from protein secondary structures can aid in understanding protein interactions for drug discovery. Chiral metasurfaces have attracted attention to enhance the intrinsically weak biomolecular optical activity for improved structural biology characterization. However, due to materials and fabrication challenges, current metasurfaces mostly operate in the visible and near-infrared regimes with limited, if any, response in far-UV. The large spectral mismatch between metasurface and biomolecular resonances limits the chiral enhancement factor. In this work, we study aluminum planar metamaterials which display optical activity in the UV region. In the first part of this work, we experimentally and computationally investigate the resonant plasmonic-biomolecular interactions in the far-UV. To the best of our knowledge, our work is the first to experimentally explore these resonant interactions in the biologically relevant far-UV regime. We demonstrate experimentally and computationally enhanced chiral sensing of sub-10 nm amino acid films. We develop a full-wave computational model of a biomolecular film on an aluminum gammadion array using experimentally derived chiral parameters (κ) for L- and DTyrosine films. Our model shows that detectable enhancements in the circular dichroism (CD) and birefringence (CB) signals from small amounts of biomolecules are only possible when tight spectral overlap exists between the plasmonic and biomolecular chiroptical signals. We support this conclusion experimentally by fabricating aluminum gammadion arrays on fused silica substrates and sublimating ultrathin racemic, L- and D- Tyrosine films on the arrays. Complete Mueller matrix analysis of the resonant plasmonic-biomolecular system agrees with our computational results and demonstrates the importance of using far-UV active metasurfaces for enhancing natural optical activity. In the second part of this work, we study hybrid aluminum reflective metasurfaces, which leverage both local and propagating surface plasmons (PSP). These materials display strong bi-anisotropy with rich polarization conversion properties. We explore several geometries and verify how their symmetry properties affect their far-field response. Our observations provide an opportunity for researchers to improve the chiral response of plasmonic metasurfaces, especially in the challenging ultraviolet regime.


The Potential Of Mixed-Species Biofilms To Address Remaining Challenges For Economically-Feasible Microalgal Biorefineries: A Review, Rebecca J. Wicker, Eilhann Kwon, Eakalak Khan, Vinod Kumar, Amit Bhatnagar Aug 2022

The Potential Of Mixed-Species Biofilms To Address Remaining Challenges For Economically-Feasible Microalgal Biorefineries: A Review, Rebecca J. Wicker, Eilhann Kwon, Eakalak Khan, Vinod Kumar, Amit Bhatnagar

Civil and Environmental Engineering and Construction Faculty Research

Several key challenges are hindering large-scale cultivation of microalgae for industrial purposes, including wastewater treatment, carbon capture, biomass production, and renewable energy production. These challenges are closely related to efficacy of 1) resource utilization, 2) biomass production, and 3) harvesting. This review describes how attached or biofilm cultivation of microalgae and/or cyanobacteria with heterotrophic bacteria in consortia could simultaneously resolve these technical obstacles, thereby reducing monetary and energetic costs of producing microalgal bioenergy. Symbiotic relationships between these organisms reduces the need for aeration or exogenous supplementation of nutrients. Additionally, this review details how increasing biodiversity correlates with diversity of functionality …


Design And Performance Of A Directional Permeability Membrane, Hamidreza Bayat Aug 2022

Design And Performance Of A Directional Permeability Membrane, Hamidreza Bayat

Mechanical Engineering Research Theses and Dissertations

A directional permeability membrane was designed, fabricated, and tested with the goal of allowing flow in one direction and preventing flow in the opposite direction. The membranes were constructed from two porous polyimide sheets with different thicknesses and bonded with double sided tape on the perimeter to create a separation in the range of 25-75 µm. Nine holes with diameter of 0.5 and 1 mm were cut in a polyimide sheet with thickness of 125 µm and four circular holes with diameter of 0.25 mm were cut in a polyimide sheet with thickness of 25 µm. The holes were cut …


Geometric Analysis Of Insect Wing Vein Network, Jacob White, Ying Hu, Sangjin Ryu, Seunghee Kim, Haipeng Zhang Aug 2022

Geometric Analysis Of Insect Wing Vein Network, Jacob White, Ying Hu, Sangjin Ryu, Seunghee Kim, Haipeng Zhang

Department of Mechanical and Materials Engineering: Faculty Publications

An insect wing consists of a thin membrane supported by a system of veins, and flow of blood through the system of veins is critical for maintaining healthy insect wings. Better understanding of the insect wing vein circulation requires to know how the efficiency of blood flow in an insect wing relates to the geometric shape of the vein. Our investigation of the wing vein network of a dragonfly Anax junius follows the idea of Murray’s law, which is established in the study of efficiency of the vein network and the geometric shape of the vein. Instead of using the …