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Optimal Thickness Distributions Of Aeroelastic Flapping Shells, Bret Stanford, Philip Beran

United States Air Force: Publications

The severe weight limitations of flapping wing micro air vehicles necessitates the use of thin flexible wings, which in turn requires an aeroelastic modeling tool for proper numerical characterization. Furthermore, due to the unconventional nature of these vehicles, wing design guidelines for thrust and/or power considerations are not generally available; numerical design optimization then becomes a valuable tool. This work couples a nonlinear shell model to an unsteady vortex lattice solver, and then computes analytical design gradients: the derivative of aerodynamic force/power quantities with respect to a large vector of thickness variables. Gradient-based optimization is then used to locate the …

Modeling Software Product Lines Using Feature Diagrams, Hazim Husain Shatnawi

Electronic Theses and Dissertations

The leading strategies for systematic software reuse focus on reuse of domain knowledge. One such strategy is software product line engineering. This strategy selects a set of reusable software components that form the core around which software products in a domain are built. Feature modeling is a process that enables engineers to identify these core assets, in particular the com(e.g., shared) and variable features of products. The focus of this thesis is to give an overview of the feature modeling process by introducing feature diagrams. Feature diagrams capture and represent comand variable properties (features) of the software products in a …

Mechanical Properties Of Portland Cement And Its Constituents At The Nano-Level, Brent French

Electronic Theses and Dissertations

The following is a summary of research for a portion of the project titled Nano to Continuum Multi-Scale Modeling Techniques and Analysis For Cementitious Materials Under Dynamic Loading in association with North Carolina Agricultural & Technical State University and the US Army. This research investigates several attempts at creating a better Portland cement model at the atomistic level through molecular dynamics simulations. These models are modified to simulate damage to the basic cement structure, and are simulated using several combinations of forcefields and molecular dynamics tools. Experimental techniques such as nanoindentation, atomic force microscopy, and x-ray diffraction are applied to …

Effect Of Doping On Β-Tricalcium Phosphate Bioresorbable Bulk Material And Thin Film Coatings, Suhaila Abdalla

Dissertations

Magnesium has emerged as a revolutionary biodegradable metal for use as an orthopedic material, it has several advantages over the permanent metallic materials currently in use, including eliminating the effects of stress shielding, improving biocompatibility and degradation properties, thus removing the requirement of a second surgery for implant removal. Due to the rapid degradation of magnesium, it is necessary to control the corrosion rates of the materials to match the rates of bone healing. This dissertation reports on the effect of doping on the properties of β-tricalcium phosphate (β-TCP). It also reports on its application as a thin film coating …

Sustainability Of Water And Wastewater Infrastructure: Using A Public-Private Partnership Model For Project Financial Assessment, Rebecca Werner Trotter

Electronic Theses and Dissertations

To supplement current and future budget shortfalls for improvements to water and wastewater infrastructure, Public-Private Partnerships (PPPs or P3) are being advocated by the American Society of Civil Engineers (ASCE) and others as a practical mechanism to ensure financial sustainability. A PPP involves a partnership between a government entity and a concessionaire--consisting of one or more private companies acting as a single, private incorporation--who make an agreement on funding, building, and operating a usually government-provided service, such as drinking water and wastewater infrastructure. This is different from a traditional contract between a government entity and a contractor because the concessionaire …

Structural Origin Of Mechanical Prowess In Conch Shells, Haoze Li

Theses and Dissertations

Conch shells are natural nanocomposites with an exquisite multiscale hierarchical architecture which exhibit coupled ultrahigh mechanical strength and toughness. What materials design strategy renders conch shells such mechanical prowess? In this study, micro/nanoscale structural and mechanical characterization of conch shells (Busycon carica) has been carried out. We demonstrate, for the first time, direct evidence that the previously claimed single-crystal third-order lamellae - the basic building blocks in conch shells are essentially assembled with aragonite nanoparticles of the size ranging from 20 to 45 nm. The third-order lamellae exhibit not only elasticity but also plasticity with the strain up to 0.7% …

Parsing The Effects Of Physical Microenvironmental Cues On Stem Cell Adhesion And Lineage Specification, Greg M. Harris

Theses and Dissertations

Tissue engineering is a broad field geared toward improving or replacing biological material and comprises an immense collection of biological nuances to consider before strategies for clinical applications can be fully realized. Physical and biochemical signals are responsible for making up a cell's microenvironment to guide morphology and function through cell-extracellular matrix signaling, cell-cell signaling, and soluble signaling. In particular, a deeper understanding of these cell-extra cellular matrix factors guiding stem cell adhesion, spreading, and differentiation is crucial to harnessing the potential to develop tissue for regenerative purposes. Mounting evidence suggests that physical cues are a key to understanding the …

Resveratrol Attenuates The Development Of Trans-Aortic Constriction (Tac) Induced Heart Failure In Mice, Prakash Kumar Gupta

Theses and Dissertations

Heart failure (HF) still remains the leading cause of morbidity and mortality and imposes severe global affliction and enormous cost on the healthcare system. Although current pharmacological therapies have shown to slow down the progression of HF, but seems to have reached their limits in improving overall patient prognosis. Thus, an immediate call for novel alternate therapies are needed which act independently as well as in conjunction with current treatment modality. Studies were performed in the well-established transverse aortic constriction (TAC) model of chronic pressure overload (PO) in mice. In the first series of studies, Male C57BL6 mice (26-28 g) …

Hyperglycemia Induces Differential Change In Oxidative Stress At Gene Expression And Functional Levels In Huvec And Hmvec, Hemang Patel, Juan Chen, Kumuda C. Das, Mahendra Kavdia

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Endothelial dysfunction precedes pathogenesis of vascular complications in diabetes. In recent years, the mechanisms of endothelial dysfunction were investigated to outline strategies for its treatment. However, the therapies for dysfunctional endothelium resulted in multiple clinical trial failures and remain elusive. There is a need for defining hyperglycemia-induced endothelial dysfunction with both generic and specific dysfunctional changes in endothelial cells (EC) using a systems approach. In this study, we investigated hyperglycemia-induced endothelial dysfunction in HUVEC and HMVEC. We investigated hyperglycemia-induced functional changes (superoxide (O₂‾), and hydrogen peroxide (H₂O₂) production and mitochondrial membrane polarization) …

Synthesis And Characterization Of Biodegradable Poly(Vinyl Esters) With Hdac Inhibitory Activity, Kyle Lawrence Horton

Wayne State University Theses

HDAC inhibitors are known to have anti-inflammatory properties. HDAC inhibitors are used in combination with Oct4 to generate induced pluripotent stem cells. I hypothesized that polyesters based on simple aliphatic HDAC inhibitors like valproic acid (VPA) and phenylbutyric acid (PBA) can serve as alternatives to existing polyester biomaterials with improved anti-inflammatory properties and as scaffolds for generation of iPSCs when used in combination with layer-by-layer thin films delivering reprogramming transcription factors. Vinyl ester of phenylbutyric acid (VEPA) and vinyl ester of valproic acid (VEVA) were synthesized from their carboxylic acid precursors using an iridium complex catalyst at yields as high …

Oligospermines For Non-Viral Sirna Delivery, Maha Elsayed

Wayne State University Theses

In this thesis, delivery systems for siRNA delivery are introduced with special attention to non-viral vectors. Many successful vectors used in vivo were reviewed. Our work focused on the effect of different architectures of oligospermine polmers on their suitability for siRNA delivery in lung cancer cells. Different archituctures showed different polyplex structures and variable transfection efficiencies. Moreover, we presented a review on nanoimprint lithography techniques with an outlook on possible biological applications in the field of gene and drug delivery.

3d Micron-Scale Imaging Of The Cortical Bone Canal Network In Human Osteogenesis Imperfecta (Oi), John R. Jameson, Carolyne Albert, Bjoern Busse, Peter A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Osteogenesis imperfecta (OI) is a genetic disorder leading to increased bone fragility. Recent work has shown that the hierarchical structure of bone plays an important role in determining its mechanical properties and resistance to fracture. The current study represents one of the first attempts to characterize the 3D structure and composition of cortical bone in OI at the micron-scale. A total of 26 pediatric bone fragments from 18 individuals were collected during autopsy (N_c=5) or routing orthopaedic procedures (N_OI=13) and imaged by microtomography with a synchrotron light source (SRµCT) for several microstructural parameters including cortical porosity …

Metacom: Automated Data Processing And Analysis Of Metagenomic Community Sequences, Cody A. Tramp, Charles D. Miller

Browse all Datasets

Advances in next generation sequencing technology have allowed metagenomic researchers to study the composition of bacterial communities through analysis of the vast numbers of sequence reads that these technologies generate. It is not feasible to analyze and interpret this large amount of data manually and individual research groups must create automated scripts and programs to analyze this data. Here, we present MetaCom, a program that offers a common set of analysis and organizational tools that can be used by research groups in the analysis of environmental samples. MetaCom is an open-source software tool that can process next generation sequencing output, …

Dual-Phase Mixed Ion And Electron Conducting Co2-Selective Permeation Membranes, Lingling Zhang

Theses and Dissertations

Fossil fuels are the dominant energy source powering our modern society. However, burning fossil fuels emits carbon dioxide (CO2), a greenhouse gas that can cause climate change and ultimately threaten the survival of humanity. Effectively mitigating CO2 emissions from the use of fossil fuels has become an intense subject of scientific research as well as political debate in recent years. The current mainstream technical approach to achieving that goal is to curb the emission of CO2 by capturing CO2 at point-sources and geologically storing it. The CO2 separation and capture process, the first step toward the ultimate storage of CO2, …

The Anti-Angiogenic Effects Of Sparstolonin B, Henry Rhodes Bateman

Theses and Dissertations

Sparstolonin B (SsnB) is a novel bioreactive compound isolated from Sparganium stoloniferum, an herb historically used in Traditional Chinese Medicine as an anti-tumor agent. SsnB has demonstrated anti-inflammatory properties, inhibiting Toll-like receptor mediated inflammation in isolated macrophages and in mice. Angiogenesis, the process of new capillary formation from existing blood vessels, is dysregulated in many pathological disorders, including atherosclerosis, diabetic retinopathy, and tumor growth. The goal of the project was to investigate the anti-angiogenic effects of SsnB.

The first part of the project utilized in vitro functional assays to study how SsnB affected endothelial cells. SsnB inhibited endothelial cell tube …

Linking Obesity To Colorectal Cancer: Recent Insights Into Plausible Biological Mechanisms, Catherine Guffey

Theses and Dissertations

Obesity has emerged as a leading environmental risk factor for the development of CRC. However, the mechanisms underlying this relationship have not yet been fully explained. Recent literature has focused on 1) inflammatory processes, 2) adipokines, and 3) estrogen. Obesity-enhanced inflammation is largely orchestrated by increases in adipose tissue macrophages leading to the secretion of TNF-alpha, MCP-1, and IL-6, all of which are linked to CRC. Adiponectin is decreased with obesity and has been reported to be negatively associated with CRC, while leptin, which is increased, is positively associated with the disease. Estrogen has been shown to influence CRC, although …

Electrokinetic Mixing And Separation In Microfluidic Systems, Fang Yang

Theses and Dissertations

Electrokinetics involves the study of liquid or particle motion under the action of an electric field; it includes electroosmosis, electrophoresis, dielectrophoresis, and electrowetting, etc. The applications of electrokinetics in the development of microfluidic devices have been widely attractive in the past decade. Electrokinetic devices generally require no external mechanical moving parts and can be made portable by replacing the power supply by small battery. Therefore, electrokinetic based microfluidic systems can serve as a viable tool in creating a lab-on-a-chip (LOC) for use in biological and chemical assays. Here we present our works of electrokenitic based mixing and separation in microfluidics …

The Effect Of Αct-1 Peptide On Bone Marrow Stromal Cells Following Injury, Adam Clay Vandergriff

Theses and Dissertations

Connexin43 (Cx43) is a component of gap junctions and is involved in intercel- lular signaling following injury to tissues. The carboxyl terminus of Cx43 binds to the PDZ2 domain of ZO-1 in order to form gap junction plaques and connect to the cytoskeleton. A biomimetic peptide known as αCT-1, replicating the last 9 amino acids found in the carboxyl terminus of CX43, has been shown to improve wound healing by preferentially binding to the PDZ2 domain of ZO-1. A possible mecha- nism for its action is through the Epithelial-Mesenchymal Transformation (EMT). Scratch assays were performed on rat bone marrow stromal …

Gelation Characteristics And Osteogenic Differentiation Of Stromal Cells In Inert Hydrolytically Degradable Micellar Polyethylene Glycol Hydrogels, Danial Barati

Theses and Dissertations

The use of polyethylene glycol (PEG) hydrogels in tissue engineering is limited by their persistence in the site of regeneration. In an attempt to produce degradable PEG-based hydrogels while preserving the unique properties of PEG, linear (LPELA) and star (SPELA) poly(ethylene glycol-co-lactide) acrylate, star (SPEDA) poly(ethylene glycol-co-dioxanone), star (SPEGA) poly(ethylene glycol-co-glycolide) acrylate as the least hydrophobic and (SPECA) poly(ethylene glycol-co-caprolactone) as the most hydrophobic macromonomers with short hydrophobic segments were synthesized. The hydrogels were characterized with respect to gelation time, modulus, water content, sol fraction, degradation, and osteogenic differentiation of encapsulated marrow stromal cells (MSCs). Chain extension of PEG with …

Dislocation Reduction In Silicon Doped High Aluminum Content Algan Layers For Deep Uv Optoelectronic Devices, Hung-Chi Chen

Theses and Dissertations

III-Nitride based deep ultraviolet (UV) light emitting diodes (LEDs) are prospective candidates to replace the conventional bulky, expensive and environmentally harmful mercury lamp as new UV light sources, used in the applications of water and air purification, germicidal and biomedical instrumentation systems, etc. Due to the lack of native substrates and poor carrier injection, AlGaN-based deep UV LED is suffering from low optical power and low overall efficiency, which prevents the availability of low cost, high efficiency deep UV LED on the market.

This dissertation is focused on improving the efficiency of deep UV LEDs, by improving the base template …

Iii-V Nitride Micro- And Nano-Scale Cantilevers For Multimodal Sensing Applications, Ehtesham Bin Quddus

Theses and Dissertations

Recent research trends in chemical and biological sensing have been geared toward developing molecular sensor devices that are fast, label free, miniaturized and portable. The performance of these devices can be dramatically improved by utilizing multimodal detection techniques, new materials and micro-/nanofabrication technologies. This is especially true for micro-/nanoscale cantilever sensors, which undergo changes in mechanical or electrical properties upon the specific binding of molecules. To develop the sensor devices with the above attributes, we utilized III-V nitride materials: InN nanowires for realizing nanoscale cantilevers and AlGaN/GaN heterostuctures with or without embedded HFETs, for developing microcantilevers. There are mainly two …

High Quality Silicon Carbide Epitaxial Growth By Novel Fluorosilane Gas Chemistry For Next Generation High Power Electronics, Tawhid Rana

Theses and Dissertations

High quality, thick (~100µm), low doped and low defect density SiC epitaxial films are essential for high voltage (blocking voltage >10kV), light, compact and reliable next generation power devices. One of the significant challenges in obtaining high quality thick SiC epitaxial films is to restrict/eliminate the Si gas-phase nucleation or aerosol formation during growth. The generated aerosol particles adversely influence growth by reducing the growth rate due to precursor losses, and also affect crystal quality, since the Si droplets are carried to the crystal growth surface. Moreover, liquid aerosol particles adhere to the various reactor parts (parasitic deposition), and contribute …

Development Of High-Throughput Catalyst Screening For Ammonia Based Selective Catalytic Reduction Of Nitric Oxide With Parallel Analysis Using Fourier Transform Infrared Imaging, Shahriar Salim

Theses and Dissertations

Lean-burn engines, which operate under excess air to fuel ratio offer significant fuel efficiency as well as contribute to the reductions of greenhouse gas emissions. However, lean burn engines produce three main pollutants carbon monoxide (CO), nitrogen oxides (NOx) and unburned or partially burned hydrocarbons (HC), which have detrimental effect on both environment and human life. The conventional three way catalyst (TWC) which was designed to reduce NOx under stoichiometric conditions is not effective under lean-burn engine exhaust condition. Recent studies have shown that copper (Cu) exchanged chabazite (CHA) type zeolites are very promising catalysts for urea or ammonia (NH3) …

Biomechanics Of Porcine Renal Artery And The Development Of A Replacment Vessel, Mohamed Gabr

Theses and Dissertations

Mechanical characterization of biological soft tissues is essential in the field of biomedical engineering. In this study several loading experiments have been performed to efficiently characterize the passive mechanical response of both native porcine renal arteries and newly developed tissue constructs. The first aim of these studies is to determine whether there is a difference in mechanical response between the main renal artery and its first branch. After fitting the bi-axial data to a Holzapfel-type constitutive model, the results show that there is no statistical difference between the model parameters for renal artery and the first branch. The only significant …

Selection And Clustering For Disease Associated Genetic Variants, Yubo Zou

Theses and Dissertations

Epigenetics is the study of chemical reactions, which are orchestrated for the development and maintenance of an organism. Genetic or epigenetic variants (GEVs) encompass different types of genetic measures, such as Deoxyribonucleic acid (DNA) methylation at different CpG sites, expression level of genes, or single nucleotide polymorphisms (SNPs). With the development of technology, huge amount of genetic and epigenetic information is produced. However, the rich information potentially brings in challenges in data analyses. Thus it is necessary to reduce the dimension of data to improve efficiency. In my dissertation, I will focus on two directions of dimension reduction: variable selection …

Phylogeny And Ancestral Genome Reconstruction From Gene Order Using Maximum Likelihood And Binary Encoding, Fei Hu

Theses and Dissertations

Over the long history of genome evolution, genes get rearranged under events such as rearrangements, losses, insertions and duplications, which in all change the ordering and content along the genome. Recent progress in genome-scale sequencing renews the challenges in the reconstructions of phylogeny and ancestral genomes with gene-order data. Such problems have been proved so interesting that a large number of algorithms have been developed rigorously over the past few years in attempts to tackle these problems following various principles. However, difficulties and limitations in performance and scalability largely prevent us from analyzing emerging modern whole-genome data, our study presented …

Computational Analysis And Prediction Of Genome-Wide Protein Targeting Signals And Localization, Jhih-Rong Lin

Theses and Dissertations

Computational prediction of protein subcellular localization can greatly help to elucidate its functions. Despite the existence of dozens of protein localization prediction algorithms, the prediction accuracy and coverage are still low. Several ensemble algorithms have been proposed to improve the prediction performance, which usually include as many as 10 or more individual localization algorithms. However, their performance is still limited by the running complexity and redundancy among individual prediction algorithms. In the first part of the dissertation, we propose a novel method for rational design of minimalist ensemble algorithms for practical genome-wide protein subcellular localization prediction. The algorithm is based …

Improved Limits And Portability Over Currently Employed Cadmium Monitoring Systems Through Preconcentration For Detection By Way Of Micro-/Nanofluidic Mechanisms, Paul F. Wach

Theses and Dissertations

Due to risk of environmental and biological accumulation of Cadmium (Cd), improved methods of early detection and monitoring must be explored as a preventative measure. Listed as one of the top three toxic heavy metals by the Environmental Protection Agency (EPA), the effects on ecological and human systems have well documented side-effects of physical mutation, reproductive sterility, kidney failure, liver disease, bone loss, and death. Found in batteries, metal plating, pigments, plastics, and cigarettes, Cd is also used as a neutron absorber in the nuclear industry as well as having 3 known radioactive isotopes. Urine Cd levels, which have been …

Comparative Evaluation Of Operating Life For Phosphate-Specific Ion Exchange Resins, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.

Tannic Acid Coated Gold Nanorods Demonstrate A Distinctive Form Of Endosomal Uptake And Unique Distribution Within Cells, Emily A. Untener, Kristen K. Comfort, Elizabeth I. Maurer, Christin M. Grabinski, Donald A. Comfort, Saber M. Hussain

Chemical and Materials Engineering Faculty Publications

One of the primary challenges associated with nanoparticle-dependent biological applications is that endosomal entrapment in a physiological environment severely limits the desired targeting and functionality of the nanoconstructs. This study sought to overcome that challenge through a systematic approach of gold nanorod (GNR) functionalization: evaluating the influence of both aspect ratio and surface chemistry on targeted cellular internalization rates and preservation of particle integrity. Owing to their unique spectral properties and enhanced surface area, GNRs possess great potential for the advancement of nanobased delivery and imaging applications. However, their ability for efficient intracellular delivery while maintaining their specific physiochemical parameters …