Engineering Commons^™

Redox-Dependent Calcium-Mediated Signaling Networks That Control The Senescence-Associated Secretory Phenotype, Akshaya Chandrasekaran

Legacy Theses & Dissertations (2009 - 2024)

Cellular senescence has evolved as a protective mechanism to arrest growth of cells with oncogenic potential. While senescent cells have lost the ability to divide, they remain metabolically active and adapt a deleterious senescence associated secretory phenotype (SASP) central to the progression of several age-associated disease pathologies. The SASP is mechanistically regulated by the pro-inflammatory cytokine interleukin-1 alpha (IL-1α) whose expression and activity is responsive to the senescence associated (SA) oxidant production and the accompanying disruption of calcium (Ca2+) homeostasis. Using primary IMR-90 human fetal lung fibroblasts as a model of replicative senescence, we explored the molecular underpinnings driving Ca2+ …

Profiling Resistance To P450-Activated Food Carcinogens Using Toxicogenomic Approaches In Budding Yeast, Nicholas Stjohn

Legacy Theses & Dissertations (2009 - 2024)

The human response to environmental carcinogens, some of which require metabolic activation, is highly variable. Factors such as environment, lifestyle, and genetics all influence the rates of exposure to and ultimate bioactivation of these compounds. Genetic factors include mutations to cell-cycle regulation, cell proliferation, and DNA repair genes; however, epidemiological studies may lack significance due to inadequate patient numbers. We used budding yeast as a model organism to determine genetic susceptibility to food-associated carcinogens, including aflatoxin (AFB1) and heterocyclic aromatic amines (HAAs). Budding yeast does not contain P450s that activate these compounds, so expression vectors were induced that contain human …

Elucidation And Optimization Of Resistive Random Access Memory Switching Behavior For Advanced Computing Applications, Zahiruddin Alamgir

Legacy Theses & Dissertations (2009 - 2024)

RRAM has recently emerged as a strong candidate for non-volatile memory (NVM). Beyond memory applications, RRAM holds promise for use in performing logic functions, mimicking neuromorphic activities, enabling multi-level switching, and as one of the key elements of hardware based encryption or signal processing systems. It has been shown previously that RRAM resistance levels can be changed by adjusting compliance current or voltage level. This characteristic makes RRAM suitable for use in setting the synaptic weight in neuromorphic computing circuits. RRAM is also considered as a key element in hardware encryption systems, to produce unique and reproducible signals. However, a …

Computational Optimization And Characterization Of Molecularly Imprinted Polymers, Jacob Jordan Terracina

Legacy Theses & Dissertations (2009 - 2024)

Molecularly imprinted polymers (MIPs) are a class of materials containing sites capable of selectively binding to the imprinted target molecule. Computational chemistry techniques were used to study the effect of different fabrication parameters (the monomer-to-target ratios, pre-polymerization solvent, temperature, and pH) on the formation of the MIP binding sites. Imprinted binding sites were built in silico for the purposes of better characterizing the receptor – ligand interactions. Chiefly, the sites were characterized with respect to their selectivities and the heterogeneity between sites.

Novel Approaches To Mitigating Bacterial Biofilm Formation And Intercellular Communication, Stephen Kasper

Legacy Theses & Dissertations (2009 - 2024)

Long thought of as solitary single-cell organisms, it is now widely accepted that bacteria can act and cooperate as social organisms. Phenomena such as biofilm formation and quorum sensing (QS) are two intimately intertwined cooperative behaviors that significantly contribute to the pathogenesis of many bacteria. Biofilms are surface associated communities of bacteria encased in a secreted extracellular matrix, which provides several advantages over an individualized lifestyle, such as increased protection from antimicrobial agents as well as enhanced opportunity for the exchange of genetic material. Bacterial QS is a system of population-based communication through the production, sensing, and response to chemical …

The Technology Development And Commercialization Of 'Smart' Scientific Instrumentations, Tony Hoang

Legacy Theses & Dissertations (2009 - 2024)

The technology development of two centrifuge-based instruments gave rise to an Internet-of-Things (IOT) biotech startup. The first instrument: the centrifuge force microscope (CFM) was recently introduced as a platform for massively parallel single-molecule manipulation and analysis. Here we developed a low-cost and self-contained CFM module that works directly within a commercial centrifuge, greatly improving accessibility and ease of use. Our instrument incorporates research grade video microscopy, a power source, a computer, and wireless transmission capability to simultaneously monitor many individually tethered microspheres. Building off of the first project, the second instrument we introduced was the “smart” centrifuge-test tube holder. The …

Towards A Biomimetic Elastin-Based Nanofiber Scaffold For Salivary Gland Tissue Regeneration And Growth Factor Delivery, Zahraa Ismail Ahmed Foraida

Legacy Theses & Dissertations (2009 - 2024)

Development of electrospun nanofibers that mimic the structural, mechanical and biochemical properties of natural extracellular matrices (ECMs) and the basement membranes is a promising approach for tissue regeneration. Electrospun fibers of synthetic polymers partially mimic the topography of the ECM, however, their high stiffness, poor hydrophilicity and lack of in vivo-like biochemical cues is not optimal for epithelial cell self-organization and function. In search of a biomimetic scaffold for salivary gland tissue regeneration, we utilized proteins and peptides to induce biomechanical and biochemical cues that resembles the native tissue environment. These functional molecules were introduced to our previously-developed poly lactic-co-glycolic …

Multifunctional Nanomaterials Utilizing Hybridization Chain Reaction For Molecular Diagnostics And Bioanalytical Applications, Md Muhit Rana

Legacy Theses & Dissertations (2009 - 2024)

DNA nanotechnology has shown great promise in molecular diagnostic, bioanalytical and biomedical applications. The great challenge of detecting target analytes, biomarkers and small molecules, in molecular diagnostics is low yield sensitivity. To address this challenge, different nanomaterials have been used for a long time and to date there is no such cost-effective bioanalytical technique which can detect these target biomarkers (DNA, RNA, circulating DNA/miRNA) or environmental heavy metal ions (Hg2+ and Ag+) in a cost-effective and efficient manner.

Novel Uses Of Directly Patternable Silicon Oxide Based Resist For Advanced Patterning Applications, Vishal Umeshbhai Desai

Legacy Theses & Dissertations (2009 - 2024)

Novel applications for the directly-patternable resist material, hydrogen silsesquioxane (HSQ), were studied for multiple advanced lithography techniques. Initially, electron beam lithography (EBL) patterned low-resolution HSQ patterns were demonstrated as a mandrel in a self-aligned double patterning (SADP) approach. Using the novel EBL-SADP approach, the number of total process steps was reduced, as compared to conventional SADP methods. This work provided proof-of-concept for using HSQ resist as a directly-patternable mandrel and plasma enhanced chemical vapor deposited (PECVD) low-stress silicon nitride (LSSiN) as a spacer. Furthermore, rapid thermal annealing (RTA) was demonstrated as a method to increase the spacer etch resistance in …

Impedance Biosensors And Deep Crater Salivary Gland Scaffolds For Tissue Engineering, Robert Arthur Schramm

Legacy Theses & Dissertations (2009 - 2024)

The salivary gland is a complex, branching organ whose primary biological function is the production of the fluid critical to alimentary function and the lubrication and maintenance of the oral cavity, saliva. The most frequent disruption of the salivary organ system is one in which the rate of supply of saliva into the oral cavity is diminished, and this may vary from a minor reduction, to near cessation. Regenerative medicine is a field which seeks to find ways to overcome the symptoms of organ malfunction or damage by inducing regrowth, repair and replacement of partial or whole organ function. Historically, …

Exploring Magnetic Nanostructures Embedded Within Single-Crystal Silicon For Generation Of Spin-Polarized Carriers, Machara Krishna Girish Malladi

Legacy Theses & Dissertations (2009 - 2024)

Integrating magnetic functionalities with silicon holds the promise of developing, in the most dominant semiconductor, a paradigm-shift information technology based on the manipulation and control of electron spin and charge. Here, we demonstrate an ion implantation approach enabling the synthesis of a ferromagnetic layer within a defect free Si environment by exploiting an additional implant of hydrogen in a region deep below the metal implanted layer. Upon post-implantation annealing, nanocavities created within the H-implanted region act as trapping sites for gettering the implanted metal species, resulting in the formation of metal nanoparticles in a Si region of excellent crystal quality. …

Mechanisms Of Euv Exposure : Photons, Electrons And Holes, Amrit Kausik Narasimhan

Legacy Theses & Dissertations (2009 - 2024)

The microelectronics industry’s movement toward smaller and smaller feature sizes has necessitated a shift to Extreme Ultra-Violet (EUV) lithography to be able to pattern sub 20-nm features, much like earlier shifts from i-line to 248 nm. However, this shift from 193-nm lithography to EUV (13.5 nm) poses significant obstacles. EUV is the first optical lithography to operate in an energy range (92 eV per photon vs. 6.4 eV per photon for 193 nm lithography) above the electron binding energies of common resist atomic species. This significant energy increase complicates resist design. For exposures of equal dose, resists receive 14 times …

Resistive Random Access Memory From Materials Development And Engineering To Novel Encryption And Neuromorphic Applications, Karsten Beckmann

Legacy Theses & Dissertations (2009 - 2024)

Resistive random access memory (ReRAM or RRAM) is a novel form of non-volatile memory that is expected to play a major role in future computing and memory solutions. It has been shown that the resistance state of ReRAM devices can be precisely tuned by modulating switching voltages, by limiting peak current, and by adjusting the switching pulse properties. This enables the realization of novel applications such as memristive neuromorphic computing and neural network computing. I have developed two processes based on 100 and 300mm wafer platforms to demonstrate functional HfO2 based ReRAM devices. The first process is designed for a …

Homo- And Heterometallic Bis(Pentafluorobenzoyl)Methanide Complexes Of Copper(Ii) And Cobalt(Ii), Janell Crowder

Legacy Theses & Dissertations (2009 - 2024)

β-Diketones are well known to form metal complexes with practically every known metal and metalloid. Metal complexes of fluorinated β-diketones generally exhibit increased volatility and thermal stability compared to the non-fluorinated analogues, and thus are used extensively in various chemical vapor deposition (CVD) processes for the deposition of metal, simple or mixed metal oxides, and fluorine-doped metal oxide thin films. Furthermore, the electron-withdrawing nature of the fluorinated ligand enhances the Lewis acidity of a coordinatively unsaturated metal center which facilitates additional coordination reactions. The physical and structural properties of fluorinated β-diketonate complexes are discussed in Chapter 1 …

Detecting And Analyzing Trna Modification Systems And Homologs Using In Silico And Colorectal Cancer Models, Khadijah Onanuga

Legacy Theses & Dissertations (2009 - 2024)

tRNA modifications can be considered epitranscriptomic signaling components that regulate translation and play integral roles in stress response pathways. As such, tRNA modification enzymes have roles in cancer etiology and potential utility as biomarkers of pathological states. For my thesis project I have used computational and wet bench approaches to study tRNA modification systems. Chapter two of my thesis deals with tRNA modification detection, as current methods are costly, time consuming, and require RNA fragmentation. I present a single-molecule-based approach for RNA modification detection, which involves in slico studies using a 5-layered graphene nanopore. Our simulations using a 1.5 nm …

Effect Of Ion Flux (Dose Rate) In Source-Drain Extension Ion Implantation For 10-Nm Node Finfet And Beyond On 300/450mm Platforms, Ming-Yi Shen

Legacy Theses & Dissertations (2009 - 2024)

The improvement of wafer equipment productivity has been a continuous effort of the semiconductor industry. Higher productivity implies lower product price, which economically drives more demand from the market. This is desired by the semiconductor manufacturing industry. By raising the ion beam current of the ion implanter for 300/450mm platforms, it is possible to increase the throughput of the ion implanter. The resulting dose rate can be comparable to the performance of conventional ion implanters or higher, depending on beam current and beam size. Thus, effects caused by higher dose rate must be investigated further. One of the major applications …

Modeling And Studying The Effect Of Texture And Elastic Anisotropy Of Copper Microstructure In Nanoscale Interconnects On Reliability In Integrated Circuits, Adarsh Basavalingappa

Legacy Theses & Dissertations (2009 - 2024)

Copper interconnects are typically polycrystalline and follow a lognormal grain size distribution. Polycrystalline copper interconnect microstructures with a lognormal grain size distribution were obtained with a Voronoi tessellation approach. The interconnect structures thus obtained were used to study grain growth mechanisms, grain boundary scattering, scattering dependent resistance of interconnects, stress evolution, vacancy migration, reliability life times, impact of orientation dependent anisotropy on various mechanisms, etc. In this work, the microstructures were used to study the impact of microstructure and elastic anisotropy of copper on thermal and electromigration induced failure.

Limited Bandwidth Wireless Communication Strategies For Structural Control Of Seismically Excited Shear Structures, Benjamin Winter

Dissertations, Master's Theses and Master's Reports

Structural control is used to mitigate unwanted vibrations in structures when large excitations occur, such as high winds and earthquakes. To increase reliability and controllability in structural control applications, engineers are making use of semi-active control devices. Semi-active control gives engineers greater control authority over structural response versus passive controllers, but are less expensive and more reliable than active devices. However, the large numbers of actuators required for semi-active structural control networks introduce more cabling within control systems leading to increased cost.

Researchers are exploring the use of wireless technology for structural control to cut down on the installation cost …

Performance Comparison Of Binarized Neural Network With Convolutional Neural Network, Lopamudra Baruah

Dissertations, Master's Theses and Master's Reports

Deep learning is a trending topic widely studied by researchers due to increase in the abundance of data and getting meaningful results with them. Convolutional Neural Networks (CNN) is one of the most popular architectures used in deep learning. Binarized Neural Network (BNN) is also a neural network which consists of binary weights and activations. Neural Networks has large number of parameters and overfitting is a common problem to these networks. To overcome the overfitting problem, dropout is a solution. Randomly dropping some neurons along with its connections helps to prevent co-adaptations which finally help in reducing overfitting. Many researchers …

Impact Of Pretreatment Methods On Fast Pyrolysis Of Biomass, Yash Donepudi

Dissertations, Master's Theses and Master's Reports

Biomass is considered a renewable source of energy with minimum carbon foot print if managed sustainably. The majority of the worlds energy is spend on transportation, and fast pyrolysis of biomass could be a potential route for production of a sustainable liquid transportation fuel. However, there are several hurdles in the conversion process. This work addresses these hurdles by investigating the impact of several pretreatment methods on fast pyrolysis including thermal pretreatment (torrefaction), comminution/grinding, mineral reduction. The impact of important parameters like heat transfer medium, conversion temperature and particle size were also investigated.

A mild thermal pretreatment of biomass (~10-15% …

Guaranteed Rendezvous For Cognitive Radio Networks Based On Cycle Length, Li Gou

Dissertations, Master's Theses and Master's Reports

Rendezvous is a fundamental process establishing a communication link on common channel between a pair of nodes in the cognitive radio networks. How to reach rendezvous efficiently and effectively is still an open problem. In this work, we propose a guaranteed cycle lengths based rendezvous (CLR) algorithm for cognitive radio networks. When the cycle lengths of the two nodes are coprime, the rendezvous is guaranteed within one rendezvous period considering the time skew between the two nodes. When T_i and T_j are not coprime, i.e., T_i=T_j, the deadlock checking and node IDs are combined …

Nanotextured Titanium Surfaces For Implants: Manufacturing And Packaging Aspects, Sachin Bhosle

Dissertations, Master's Theses and Master's Reports

It has been shown that nanotexturing the surface of otherwise smooth titanium orthopedic materials increases osteoblast proliferation in vitro, and the bone-implant contact area and pullout force in vivo. However, this prior work has not focused on the requirements for scale-up to industrial processes. This dissertation reports on titanium surface modifications by electrochemical anodization using a benign NH₄F electrolyte, and a hybrid electrolyte also containing AgF, rather than hazardous hydrofluoric acid used elsewhere. Nanotube fabrication of Ti6Al4V foils, rods, thermal plasma sprayed commercial implants, and laser and e-beam melted powder materials was demonstrated.

It was found …

Ecological Sanitation Opportunities In Rural Panamá: Effectiveness And Social Implications Of Intrinsic Ammonia-Based Treatment For Pathogen Inactivation And Incorporation Of Ferrocement Technology, David Kierys

Dissertations, Master's Theses and Master's Reports

The Millennium Development Goals (MDGs) the United Nations created more than 15 years ago established a global developmental framework that set a precedent for many governmental agencies and non-governmental organizations (NGOs.). With the deadline having come and gone many of the objectives set out in the original eight MDGs have come to fruition (Joint Monitoring Program, 2015). One exemplary achievement by the global community, specifically to the Water, Sanitation and Hygiene (WASH) sector was providing 91 percent of the world’s population with access to improved sources of drinking water (UNICEF/WHO, 2015). But, as the Joint Monitoring Program (JMP) – the …

Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li

Dissertations, Master's Theses and Master's Reports

Electric field-induced antiferroelectric(AFE)/paraelectric(PE)-to-ferroelectric(FE) phase transitions are investigated for the associated nonlinear dielectric behavior, which could offer high dielectric capacity. The phenomenon in monolithic materials has been computed for Kittel antiferroelectric and BaTiO₃ model systems using the Landau-Ginzburg-Devonshire theory. The general switching curves give values of the polarization as a function of external electric field. A similar computation is performed for particle-filled polymer-matrix composites where an internal depolarization field is considered. The polarization-electric field response changes with different depolarization factors, which demonstrate the shape and alignment of the dielectric particles embedded in polymer-matrix are key factors for the composite to …

High Performance Multiview Video Coding, Caoyang Jiang

Dissertations, Master's Theses and Master's Reports

Following the standardization of the latest video coding standard High Efficiency Video Coding in 2013, in 2014, multiview extension of HEVC (MV-HEVC) was published and brought significantly better compression performance of around 50% for multiview and 3D videos compared to multiple independent single-view HEVC coding. However, the extremely high computational complexity of MV-HEVC demands significant optimization of the encoder. To tackle this problem, this work investigates the possibilities of using modern parallel computing platforms and tools such as single-instruction-multiple-data (SIMD) instructions, multi-core CPU, massively parallel GPU, and computer cluster to significantly enhance the MVC encoder performance. The aforementioned computing tools …

Improving The Simulation Of Large Lakes In Regional Climate Modeling: Two-Way Lake-Atmosphere Coupling With A 3d Hydrodynamic Model Of The Great Lakes, Pengfei Xue, Jeremy S. Pal, Xinyu Ye, John D. Lenters, Chenfu Huang, Philip Y. Chu

Civil and Environmental Engineering Faculty Works

Accurate representations of lake–ice–atmosphere interactions in regional climate modeling remain one of the most critical and unresolved issues for understanding large-lake ecosystems and their watersheds. To date, the representation of the Great Lakes two-way interactions in regional climate models is achieved with one-dimensional (1D) lake models applied at the atmospheric model lake grid points distributed spatially across a 2D domain. While some progress has been made in refining 1D lake model processes, such models are fundamentally incapable of realistically resolving a number of physical processes in the Great Lakes. In this study, a two-way coupled 3D lake-ice–climate modeling system [Great …

The Long Term Effects Of An Aging Fleet On Operational Availability And Cost: Evidence From The Us Coast Guard, Christopher W. Lavin, Robert M. Mcnab, Ryan S. Sullivan

Economics Faculty Publications

This paper empirically examines whether the aging of a fleet affects operational availability and operating cost using a unique data-set on the 117 47-foot Motor Lifeboats (MLBs) of the United States Coast Guard (USCG). Procured from 1997 to 2003, the 47-foot MLB is the standard lifeboat of the USCG and all 117 MLBs remain in service. The aging of the MLB fleet has resulted in higher annual operating costs and lower operational availability, although the nature of this relationship remains unclear. Our estimation strategy utilizes an error components estimator to examine these issues. We employ three variants of the dependent …

Stem Outreach Efforts For Urban Students, Otilia Popescu, Vukica M. Jovanovic, Jennifer G. Michaeli, Stacie Ringleb, Alok Verma

Engineering Technology Faculty Publications

Four-year universities and community colleges rely on outreach efforts to bring the awareness of STEM-related careers to students, who might be interested in joining their student body in the future. These events are of utmost importance for students, who do not have all of the necessary role models to engage them in conversation about their future careers. Some students might not perceive a STEM career as valuable and feasible in their future career paths, even if their own schools offer information and resources related to STEM career pathways. Hence, various outreach efforts at different levels of education have to be …

Career And Technical Education And Its Relationship To Engineering Technology Pathways In Marine Mechatronics, Vukica M. Jovanovic, Otilia Popescu, Petros Katsioloudis, Ana M. Djuric, Mileta M. Tomovic, Thomas Stout, Roger R. Lagesse

Engineering Technology Faculty Publications

Students coming from families with low household incomes often cannot afford to rely on a regular pathway from high school to the university because of college tuition rates. Other students might not seek out available opportunities in their guidance counselors' offices to learn about existing scholarships or learn about different engineering technology or engineering careers. There are also students, who realize that a four-year university degree is not always necessary to find a career that matches their skills and talents. They may also have another educational path to receive a technician, engineering technology, or engineering degree, such as technical or …

Power Budgets For Cubesat Radios To Support Ground Communications And Inter-Satellite Links, Otilia Popescu

Engineering Technology Faculty Publications

CubeSats are a class of pico-satellites that have emerged over the past decade as a cost-effective alternative to the traditional large satellites to provide space experimentation capabilities to universities and other types of small enterprises, which otherwise would be unable to carry them out due to cost constraints. An important consideration when planning CubeSat missions is the power budget required by the radio communication subsystem, which enables a CubeSat to exchange information with ground stations and/or other CubeSats in orbit. The power that a CubeSat can dedicate to the communication subsystem is limited by the hard constraints on the total …