Digital Commons Network^™

Study Of Sac Solder Interconnect Parameters In Microelectronic Semiconductor Packaging And Their Effects On Electromigration Failure Mechanisms, Allison Theresa Osmanson

Material Science and Engineering Dissertations - Archive

As the shrinkage of electronic devices becomes more appealing, so do their high capacity and efficiency. This demand for ever-shrinking sizes of electronic devices follows the trend predicted by Moore’s Law. To achieve smaller devices, reduced sizes of solder joints, Cu traces, Cu pads, and other components in packages are implemented with tighter tolerances for geometries and layouts. With each incremental change in dimension or material, new reliability challenges emerge. Electromigration (EM), the directional diffusion of atoms with the flow of electrons, has been an inevitable reliability concern for microelectronic device packaging. It is one common failure mechanism in wafer-level …

Study On Forming Dna-Mediated Nanoparticle Conjugates: Toward Detection Of Covid-19, Chinmay Nitin Afzulpurkar

Material Science and Engineering Theses - Archive

The objective of this thesis is to establish a rapid, robust, and reproducible procedure to controllably assemble DNA-functionalized Au nanoparticles (AuNPs) into satellite-shaped nanostructures using sequence-specific DNA hybridization. A target DNA strand with COVID-19 sequence (t-DNA) is used as a bridge to connect a capture DNA functionalized on a 50nm gold nanoparticle (C-AuNP) and a probe DNA functionalized on a 30nm nanoparticle (P-AuNP), creating C-AuNP/t-DNA/P-AuNP conjugates. The C-DNA is complementary to a portion of t-DNA, and P-DNA is complementary to the other portion of t-DNA. The parameters that affect the conjugate formation, including hybridization buffer strength, hybridization temperature, and DNA …

Change In Sedimentation Regime Due To Bridge Construction Activities: A Field Study At Fm 2478 Bridge Over Wilson Creek, Mckinney, Texas, Subhas Kandel

Civil Engineering Theses - Archive

Bridge construction activities can cause soil disturbances that introduce sediments into a receiving stream and potentially impact its quality and the ecosystem. The impacts of bridge construction activities are studied in two ways: overland erosion and in-stream sediment concentration. For this research, the overland erosion of Wilson Creek in McKinney, Texas was monitored from four erosion plots constructed on its banks, near the bridge construction activities zone. The instream water quality was examined during the construction period by measuring the Total Suspended Solids (TSS) and the turbidity of water samples, and the sediment and water samples were collected and analyzed …

Collaborative Human-Machine Interfaces For Mobile Manipulators., Shamsudeen Olawale Abubakar

Electronic Theses and Dissertations

The use of mobile manipulators in service industries as both agents in physical Human Robot Interaction (pHRI) and for social interactions has been on the increase in recent times due to necessities like compensating for workforce shortages and enabling safer and more efficient operations amongst other reasons. Collaborative robots, or co-bots, are robots that are developed for use with human interaction through direct contact or close proximity in a shared space with the human users. The work presented in this dissertation focuses on the design, implementation and analysis of components for the next-generation collaborative human machine interfaces (CHMI) needed for …

Structural Dynamics And Encapsulation Properties Of Polyelectrolyte Complex Micelles, Sachit Shah

Electronic Theses and Dissertations, 2020-2023

Charged therapeutics such as nucleic acids and proteins can treat a vast range of human diseases that are traditionally undruggable. Their broadness in treating disease is due to their ability to influence cellular function. However, their high charge density and physiological barriers such as enzymatic degradation, hinder the deliverability of these molecules to the sites of disease. Polyelectrolyte complex (PEC) micelles are core-corona nanostructures that can encapsulate charged molecules and offer a platform for delivery. PECs form the core, when two oppositely charged polyelectrolytes are mixed in an aqueous solution, and the micelle corona is a neutral hydrophilic polymer that …

The Effect Of Green Biobased Binder On Structural, Mechanical, Liquid Absorption And Wetting Properties Of Coated Papers, Bilge N. Altay, Charles Klass, Ting Chen, Alexandar Fleck, Cem Aydemir, Arif Karademir, Paul D. Fleming

Articles

Synthetic styrene-butadiene (SB) and styrene-acrylic (SA) latex binders used in paper coating formulations are common and based on unsustainable petroleum sources. Today's papermaking industry turns towards sustainable substitutes that do not compromise quality, and reduce carbon emission, toxic substance release and waste disposal concerns related to fossil fuel sources. In this study, colloidal starch-based latex nanoparticles that do not require cooking were used for pigment coating and coated on the paper surfaces. The effects of these new biobased binders on the structural and mechanical strength properties, liquid absorption, wetting and surface topography of the paper were investigated and compared with …

Tissue Engineering And The Effect Of Volumetric Muscle Loss On Muscle Performance, Alex Pemberton

Biomedical Engineering Undergraduate Honors Theses

Trauma, for so many people, creates life altering injuries. One of the major injuries that results from trauma is volumetric muscle loss (VML), which is the loss of muscle tissue that cannot be naturally regenerated and results in chronic loss of function. When a small amount of damage is done to a muscle, but the underlying extracellular matrix of the cell is still intact, the muscle can regenerate much of its volume and function. If the injury damages the extracellular matrix, the injury site is instead filled with scar tissue, which cannot regenerate muscle mass or function. Seen widely in …

Siderophore-Mediated Zinc Acquisition Enhances Enterobacterial Colonization Of The Inflamed Gut, Judith Behnsen, Hui Zhi, Allegra T. Aron, Venkateswaran Subramanian, William Santus, Michael H. Lee, Romana R. Gerner, Daniel Petras, Janet Z. Liu, Keith D. Green, Sarah L. Price, Jose Camacho, Hannah Hillman, Joshua Tjokrosurjo, Nicola P. Montaldo, Evelyn M. Hoover, Sean Treacy-Abarca, Benjamin A. Gilston, Eric P. Skaar, Walter J. Chazin, Sylvie Garneau-Tsodikova, Matthew B Lawrenz, Robert D Perry, Sean-Paul Nuccio, Pieter C. Dorrestein, Manuela Raffatellu

Pharmacy Nuclear Magnetic Resonance Center Faculty Publications

Zinc is an essential cofactor for bacterial metabolism, and many Enterobacteriaceae express the zinc transporters ZnuABC and ZupT to acquire this metal in the host. However, the probiotic bacterium Escherichia coli Nissle 1917 (or “Nissle”) exhibits appreciable growth in zinc-limited media even when these transporters are deleted. Here, we show that Nissle utilizes the siderophore yersiniabactin as a zincophore, enabling Nissle to grow in zinc-limited media, to tolerate calprotectin-mediated zinc sequestration, and to thrive in the inflamed gut. We also show that yersiniabactin’s affinity for iron or zinc changes in a pH-dependent manner, with increased relative zinc binding as the …

Glycan Functionalization Of Iron Oxide Nanoparticles (Ionps) As A Method Of Inactivating Antibiotic Resistant Neisseria Gonorrhoeae Via A Magnetically Mediated Energy Delivery (Magmed) System, Cedric Taylor

All Theses

With the increase of antibiotic resistant bacteria, current established therapeutic treatment methods are rapidly demonstrating decreasing efficacy. For this project, we are studying a novel alternate mechanism of treating antibiotic resistant bacteria by utilizing magnetic iron oxide nanoparticles (IONPs) coated with a heterobifunctional polyethylene glycol polymer (PEG) and functionalized with glycan structures that can interact with Neisseria gonorrhoeae FA1090. Interaction between the IONPs and bacteria is manipulated by an external alternating magnetic field (AMF) in a process known as magnetically mediated energy delivery (MagMED). Magnetic IONPs were synthesized and reacted with PEG (PEG-IONPs) and functionalized with glycans Gal(α1-3)Gal(β1-4)Glc(β1-1) (common name: …

Genome Annotation Using Average Mutual Information, Garin P. Newcomb

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Advancements in high-throughput DNA sequencing technologies and ambitious goals for their use are resulting in the generation of a deluge of unannotated sequenced genomes. This makes computational tools that can aid in annotation increasingly valuable.

Here, we provide a detailed exploration of the utility as well as the limitations of average mutual information (AMI) in several steps of genome annotation. For a genomic sequence, AMI is a measure of the information a base contains about the base separated by a fixed lag. A profile is constructed by calculating AMI at multiple lags. In addition to traditional AMI, we employ two …

Comparative Analysis Of Kmer Counting And Estimation Tools, Ankitha Vejandla

School of Computing: Dissertations, Theses, and Student Research

The rapid development of next-generation sequencing (NGS) technologies for determining the sequence of DNA has revolutionized genome research in recent years. De novo assemblers are the most commonly used tools to perform genome assembly. Most of the assemblers use de Bruijn graphs that break the sequenced reads into smaller sequences (sub-strings), called kmers, where k denotes the length of the sub-strings. The kmer counting and analysis of kmer frequency distribution are important in genome assembly. The main goal of this research is to provide a detailed analysis of the performance of different kmer counting and estimation tools that are currently …

Formation Of B Horizons In Engineered Putting Green Soils, Glen R. Obear

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Engineered turfgrass putting green soils are designed to drain quickly, while maintaining adequate water- and nutrient-holding capacity to sustain plant growth. These soils are designed to meet specific performance characteristics when they are constructed, but the process of soil formation changes these characteristics over time. Chapter 1 of this dissertation is a literature review of soil formation in engineered putting green soils. Pedogenesis of putting greens is such that A horizons form as organic matter accumulates near the surface, and B horizons form as particles and solutes are translocated to textural or pH boundaries in soil profiles. In the engineered …

Water Recovery From Bioreactor Mixed Liquors Using Forward Osmosis With Polyelectrolyte Draw Solutions, Calen Raulerson

All Theses

The objective of this research was to test the feasibility of using forward osmosis (FO) with polyelectrolyte draw solutions to recover water from bioreactor mixed liquors. When combined with an Anaerobic Osmotic Membrane Bioreactor (AnOMBR), such a system could process fecal and food waste from astronauts aboard the International Space Station (ISS) and reclaim important nutrients and water. This project focused on measuring the obtainable water recovery rates from bioreactor effluent, and the identifying challenges associated with the operation.

AnOMBRs feature several advantages over aerobic bioreactors, and non-osmotic anaerobic membrane bioreactors (AnMBR). Anaerobic bioreactors avoid the significant energy costs of …

Development And Validation Of An Analytical Modeling Tool For Solar Borehole Heat Exchangers, Adam Ornelles

All Theses

Current numerical modeling solutions used for subsurface heat flow, such as the Berkeley TOUGH codes, are often difficult to use and time-consuming compared to analytical modeling methods. However, current analytical modeling methods for subsurface heat flow and groundwater cannot accurately model the subsurface in 3 dimensions, a feature paramount to the planning and installation of thermal borehole heat exchangers used in environmental remediation.

This research developed a novel 3-dimensional analytical modeling tool for solar-powered borehole heat exchangers. The analytical modeling tool can plan thermal remediation systems while being more straightforward to operate than current numerical modeling software. By creating a …

Investigation On Effects Of Lactate Adaptation Using Metabolic Indicators And Amino Acids To Explore Cell Metabolism, Lisa Uy

All Theses

Biopharmaceutical products are drugs that are made from living cells. One protein type of high importance to biopharmaceuticals is monoclonal antibodies. Monoclonal antibodies allow for highly specific, targeted treatment of diseases and detection of molecules related to diseases. With major roles in detecting and/or treating diseases like human immunodeficiency virus (HIV), coronavirus disease 2019 (COVID-19), and some cancers, monoclonal antibodies are in demand. This demand has led to a need for efficient cell culture systems to produce high yields of protein with minimal waste. The most commonly used cell culture system for these high-value proteins is Chinese hamster ovary (CHO) …

Greenhouse Tomatoes: Process Simulation, Juan Gabriel Marin Jr.

Graduate Theses and Dissertations

Growing population demand and challenges brought on by climate change have spurred the need for more resilient fruit and vegetable supply chains. One agricultural technology of significant interest is the use of greenhouses for food production. Greenhouses create a stable and adaptable environment for crops such as tomatoes to grow year-round. Fresh tomatoes are the second most consumed vegetable per capita in U.S. diets, currently averaging 20.7 pounds. The growing consumption of fresh tomatoes has been the result of increasing cultural diversity in the United States.

To meet the growing demand, Venlo-type greenhouses have been frequently used by growers. It …

Multifunctional Programmable Self-Assembled Nanoparticles In Nanomedicine, Yoshie Sakamaki

Graduate Theses and Dissertations

Developing methodologies to control the architecture of nanoparticles (NPs) at the atomic level prevents their inhomogeneity and leads to a variety of expected functions. Rationally designed nanoparticles can either be programmed or crystallized structures into pre-determined structures achieving tunable particle pore size and physiochemistry. In this dissertation, two broad classes of multifunctional nanoparticles are developed, metal-organic frameworks and DNA-NP aggregates.

Metal-organic frameworks are a novel class of highly porous crystalline materials built from organic linkers and metal cluster-based secondary building units. However, applications in bioremediation have not been developed very well especially in applications regarding drug delivery systems (DDS). The …

Synthesis Of Polyethylene Glycol-Based Hydrogels And Silver/Gold Nanostructures For Biomedical Applications, Isabelle Ishimwe Niyonshuti

Graduate Theses and Dissertations

This work focuses on the synthesis of biocompatible polyethylene glycol (PEG)-based hydrogels, silver nanoparticles (AgNPs), and silver-gold nanocages (Ag-AuNCs) for biomedical applications. The dissertation includes two parts with Part I on the work of PEG-based hydrogel for wound healing applications and Part II on the work of Ag/Au nanostructures for antimicrobial applications. Part I studies PEG-based hydrogel for the delivery of fibroblast growth factors (FGFs) for wound healing applications, aiming to overcome the challenge of designing hydrogels capable of the sustained release of bioactive FGFs. This research develops new biocompatible anionic injectable hydrogel formulations based on Poly (Oligo Ethylene Glycol …

Two-Dimensional Black Phosphorus For Terahertz Emission And Near-Field Radiative Heat Transfer, Mahmudul Hasan Doha

Graduate Theses and Dissertations

The main focus of this work is to investigate two potential optical and optoelectronic applications of black phosphorus (BP): the near-field radiative heat transfer in plasmonic heterostructures with graphene and terahertz emission from multi-layer BP photoconductive antennas. When the separation distance between graphene-black phosphorene is much smaller than or comparable to the thermal wavelength at different temperatures, a near-field radiation heat transfer breaks the Planck blackbody limit. The magnitude of the near-field radiation enhancement acutely depends on the gate voltage, doping, and vacuum gap of the graphene and BP pair. The strong near-field radiation heat transfer enhancement of the specific …

Understanding The Chemical Structures Of Polydopamine, Deborah Takyibea Okyere

Graduate Theses and Dissertations

Polydopamine (PDA) is described as a bioinspired polymer produced by a method involving the chemical oxidation of dopamine in a pH-dependent medium. It has been used for the functionalization of nanomaterials in diverse applications including drug delivery and biosensing because of its strong adhesiveness, functionality is easily modified, and biocompatibility with mammalian cells and tissues. The polymerization process is believed to be initiated by the autoxidation of dopamine to dopaminequinone. However, the repeating units, as well as the final structure of PDA, are not well understood. Hence, this work focuses on the characterizations of the PDA structures during formation and …

Optimization Of Nitrogen Removal Rate In One-Stage Reactor Through Partial Nitrification Anammox Process During Direct Treatment Of Poultry Litter Wastewater, Yiting Xiao

Graduate Theses and Dissertations

Anammox is an increasingly common process used for the treatment of reject water and even mainstream wastewater due to its low oxygen demand. However, anammox is not commonly utilized in the direct treatment of poultry litter because of the high organic content, which would inhibit the anammox process. Thus, this project is aimed at optimizing the nitrogen removal rate through partial nitrification anammox process (PN/A) to treat synthetic poultry litter wastewater. Nitrogen removal efficiencies will therefore be improved through optimizing the combination of three operating parameters including hydraulic retention time (HRT), dissolved oxygen (DO) concentration, and carbon to nitrogen (C/N) …

Towards Long Term Colloid Suspension In A Vertically Rotated System., Md Mahmudur Rahman

Electronic Theses and Dissertations

Within a colloidal suspension gravity may compromise the observation of governing physical interactions, especially those that are weak and/or take significant time to develop. Conducting the experiment in a long-term microgravity environment is a viable option to negate gravitational effects, though significant resources are required to do so. While it may not be possible to simulate long-term microgravity terrestrially, particles can resist quick sedimentation in a confined suspension system rotating vertically with appropriate rotation speed. The goal of the investigation is to demonstrate the existence of long-term particle suspension regime for a certain colloidal suspension while characterizing colloidal behavior due …

Digital Design And Thermomechanical Process Simulation For 3d Printing With Abs And Soyhull Fibers Reinforced Abs Composites., Saleh Khanjar

Electronic Theses and Dissertations

Recent demonstrations with fused filament fabrication (FFF) 3D printing have shown to produce prototypes as well as production components. Additionally, due to the FFF process platforms being low-cost and readily available there has been a high-demand to produce on-demand parts for various applications in automotive, in-space manufacturing and electronic industries. However, current limitations such as limited availability of advanced composites materials, and guidelines for design-for-manufacturing make the process prone to trial-and-error experiments both at the materials development, product design and manufacturing stage. In this work, new thermomechanical process simulations platform, Digimat-AM has been evaluated to address and demonstrate digital design …

Materials And Process Design For Ceramic Fused Filament Fabrication (Cf3) Of Hydroxyapatite., Kavish Sudan

Electronic Theses and Dissertations

Ceramic fused filament fabrication (CF3) enables the fabrication of highly customizable ceramic parts at relatively lower costs compared to other AM technologies. Advanced ceramics, having specific or niche applications, call for a high level of accuracy to meet the performance requirements. For achieving the desired level of accuracy in any manufacturing process, it is important to know the effect of involved parameters at different stages of fabrication. CF3 has been around for a while but there has been a severe lack of literature dealing with understanding the effect of process parameters on the final part properties. In this study, Hydroxyapatite …

Accelerated Performance Degradation Of Single-Phase Cold Plates For Direct-To-Chip Liquid Cooled Data Centers, Lochan Sai Reddy Chinthaparthy

Mechanical and Aerospace Engineering Theses - Archive

Expanding demands for cloud-based computing and storage, the Internet of Things, and AI-based applications have escalated thermal loads in high-density data centers which necessitated the utilization of more efficient cooling technologies. Direct-to-chip liquid cooling using cold plates has proven to be one of the most efficient methods to dissipate the high heat fluxes of modern high-power CPUs and GPUs. While the published literature has well-documented research on the thermal aspects of direct liquid cooling, a detailed account of reliability degradation is missing. The present investigation provides an in-depth analysis of the reliability degradation of copper cold plates used in high-power …

Self Adaptive Reinforcement Learning For High-Dimensional Stochastic Systems With Application To Robotic Control, Sayyed Jaffar Ali Raza

Electronic Theses and Dissertations, 2020-2023

A long standing goal in the field of artificial intelligence (AI) is to develop agents that can perceive richer problem space and effortlessly plan their activity in minimal duration. Several strides have been made towards this goal over the last few years due to simultaneous advances in compute power, optimized algorithms, and most importantly evident success of AI based machines in nearly every discipline. The progress has been especially rapid in area of reinforcement learning (RL) where computers can now plan-ahead their activities and outperform their human rivals in complex problem domains like chess or Go game. However, despite encouraging …

Investigation Of Optical And Structural Properties Of Gesn Heterostructures, Oluwatobi Gabriel Olorunsola

Graduate Theses and Dissertations

Silicon (Si)-based optoelectronics have gained traction due to its primed versatility at developing light-based technologies. Si, however, features indirect bandgap characteristics and suffers relegated optical properties compared to its III-V counterparts. III-Vs have also been hybridized to Si platforms but the resulting technologies are expensive and incompatible with standard complementary-metal-oxide-semiconductor processes. Germanium (Ge), on the other hand, have been engineered to behave like direct bandgap material through tensile strain interventions but are well short of attaining extensive wavelength coverage. To create a competitive material that evades these challenges, transitional amounts of Sn can be incorporated into Ge matrix to form …

Investigating Effects Of Microenvironmental Stress On Cell Metabolism Using Multiphoton Imaging, Lisa Rebello

Graduate Theses and Dissertations

Resistance to therapy in cancer is a major cause of poor prognosis in patients. Tumor hypoxia plays an active role in mediating treatment resistance and has been linked to metastases and metastatic potential in cancer. Our research focused on three objectives: i) To understand metabolic effects of chronic and intermittent hypoxia in murine breast cancer cells and its affiliation with metastatic potential ii) To identify the metabolic changes associated with radiation therapy in a panel of radiosensitive and radioresistant human head and neck cancer cells and iii) to monitor the changes in cell metabolism associated with gain of treatment resistance. …

Recombinant Production And Purification Of Green Fluorescent Protein (Gfp)-Fused Metal Binding Protein For Palladium Nanoparticle Synthesis, Shadrach Ibinola

Graduate Theses and Dissertations

In lieu of chemical and physical methods, biologically guided synthesis is increasingly used as a cost-effective medium for the fabrication of nanoparticles (NP). Recently, a palladium metal binding sequence Pd4 (TSNAVHPTLRHL) has been demonstrated to be instrumental in the production of palladium (Pd) nanoparticles. Although, by eliminating the additional cost of purification of the protein, the crude lysate of E. coli containing Pd specific protein has been proven to be a viable cost-effective means for the synthesis of Pd NP, studies have not be done to ascertain the comparative catalytic activity of nanoparticles synthesized from both clarified lysate and pure …

Using Peptide Design To Engineer Polyelectrolyte Complex Biomaterials, Sara Tabandeh

Electronic Theses and Dissertations, 2020-2023

The self-assembly of oppositely charged polymers provides a versatile platform to design materials for diverse applications in biology and medicine. Electrostatically-driven phase separation of oppositely charged polymers in aqueous solution gives rise to the formation of a polymer-rich phase called a polyelectrolyte complex (PEC). PECs can be in the form of liquid droplets (complex coacervates) or amorphous solid precipitates. Unlike synthetic polymers, peptides are good candidates for developing tailor-made formulations and structure-property relationships due to their biocompatibility, precise control over sequences, and ability to program hydrogen bonding interactions. However, little is known about the effect of combining additional molecular interactions …