Digital Commons Network^™

Coordination Geometries In Metallobundles Enforcing Oxidative And Hydrolytic Catalysis And Designing Biomaterials For Use As Antimicrobials, Jennifer Yoon

Dissertations - ALL

De novo protein design permits discovery of intricate folds and functions emulating natural enzymes in simpler, yet robust model constructs. Helical bundles serve as premier scaffolds to incorporate diverse reactivities from oxidative, reductive, to hydrolytic transformations observed in much grander O2-utilizing metalloproteins such as radical-generating ribonucleotide reductases and catalases. One notable family of de novo proteins is the Due Ferri or DF series of four-helix bundles providing a dinuclear site for metal incorporation and are amenable for tailoring active site reactivity. As reactive oxygen species and radical-based intermediates are prevalent and necessary for steering life-essential processes through reactive radicals stabilized …

Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson

Dissertations and Theses

Earthquake liquefaction hazards in silty soils are a critical problem in Portland, Oregon, and other areas around the world. This is a particular problem for existing facilities founded on liquefiable soils, for which there exists no cost-effective liquefaction mitigation solution at the present time. It is essential from both a seismic safety and a seismic resilience perspective to be able to mitigate potentially liquefiable soils underneath existing structures, and to do so in a cost-effective manner. Recent studies suggest that liquefaction mitigation using microbially-induced desaturation (MID) may provide this capability.

The objective of MID is to reduce earthquake-induced excess pore …

Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki

Dissertations and Theses

Cyanobacteria exist throughout the world and are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change, increased nutrient loading, and other anthropogenic impacts on waterbodies are expected to increase the prevalence of cyanobacteria. It is vital that we protect our drinking water supplies and natural water resources. Modeling the production and movement of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. Cyanotoxins are diverse and the conditions under which they are formed …

Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas

Dissertations and Theses

Diatoms are single-celled organisms of various shapes and sizes typically found in aquatic environments. When diatoms die, the organic material decomposes, and the outer skeletons (i.e., frustules) settle and accumulate as sedimentary deposits. These soils, called diatomaceous soils, exhibit nontraditional behavior since the diatom particles are typically hollow skeletons composed of amorphous silica with intricately patterned and abrasive surfaces. Recent studies have shown that diatomaceous soils are challenging geomaterials since even a small percentage of diatom particles will notably affect engineering behavior. Furthermore, laboratory studies on diatomaceous soil mixtures have demonstrated that many engineering soil properties depend on the percentage …

Alteration Of The Canine Metabolome After A 3-Week Supplementation Of Cannabidiol (Cbd) Containing Treats: An Exploratory Study Of Healthy Animals, Elizabeth M. Morris, Susanna E. Kitts-Morgan, Dawn M. Spangler, Ibukun M. Ogunade, Kyle R. Mcleod, David L. Harmon

Animal and Food Sciences Faculty Publications

Despite the increased interest and widespread use of cannabidiol (CBD) in humans and companion animals, much remains to be learned about its effects on health and physiology. Metabolomics is a useful tool to evaluate changes in the health status of animals and to analyze metabolic alterations caused by diet, disease, or other factors. Thus, the purpose of this investigation was to evaluate the impact of CBD supplementation on the canine plasma metabolome. Sixteen dogs (18.2 ± 3.4 kg BW) were utilized in a completely randomized design with treatments consisting of control and 4.5 mg CBD/kg BW/d. After 21 d of …

Tailoring Exceptional Points In A Hybrid Pt-Symmetric And Anti-Pt-Symmetric Scattering System, Zhicheng Xiao, Andrea Alù

Advanced Science Research Center

Fano resonances feature an asymmetric lineshape with controllable linewidth, stemming from the interplay between bright and dark resonances. They provide efficient opportunities to shape the scattering lineshape, but they usually lack flexibility and tunability and are hindered by loss in passive systems. Here, we explore a hybrid parity-time (PT) and anti-parity-time (APT) symmetric system supporting unitary scattering features with highly tunable Fano resonances. The PT-APT-symmetric system can be envisioned in nanophotonic and microwave circuit implementations, allowing for real-time control of the scattering lineshape and its underlying singularities. Our study shows the opportunities enabled by non-Hermitian platforms to control scattering lineshapes …

On Communication For Distributed Babai Point Computation, Maiara F. Bollauf, Vinay A. Vaishampayan, Sueli I.R. Costa

Publications and Research

We present a communication-efficient distributed protocol for computing the Babai point, an approximate nearest point for a random vector X∈Rn in a given lattice. We show that the protocol is optimal in the sense that it minimizes the sum rate when the components of X are mutually independent. We then investigate the error probability, i.e. the probability that the Babai point does not coincide with the nearest lattice point, motivated by the fact that for some cases, a distributed algorithm for finding the Babai point is sufficient for finding the nearest lattice point itself. Two different probability models for X …

Nonlinear Schrödinger Equation Solitons On Quantum Droplets, A. Ludu, A.S. Carstea

Publications

Irrotational flow of a spherical thin liquid layer surrounding a rigid core is described using the defocusing nonlinear Schrödinger equation. Accordingly, azimuthal moving nonlinear waves are modeled by periodic dark solitons expressed by elliptic functions. In the quantum regime the algebraic Bethe ansatz is used in order to capture the energy levels of such motions, which we expect to be relevant for the dynamics of the nuclear clusters in deformed heavy nuclei surface modeled by quantum liquid drops. In order to validate the model we match our theoretical energy spectra with experimental results on energy, angular momentum, and parity for …

Hydrus-1d Modeling To Represent Hydrologic Performance Of The Oncenter Green Roof, Courtney Gammon

Theses - ALL

Green infrastructure has the potential to alleviate stormwater runoff and reduce combined sewer overflows. Green roofs have stormwater mitigation potential in urban areas but further analysis to predict performance is needed. This research aims to understand how rainfall parameters affect green roof retention and reduction during storm events and whether a one-dimensional hydrologic model can be used to accurately predict performance. An extensive network of sensors on the OnCenter green roof in downtown Syracuse, New York, was utilized for analysis and modeling. This roof is larger than nearly all other green roofs that have been previously studied, and the layer …

Assessment Of Pluvial Flooding In Syracuse, Ny, Using High-Resolution Topographic Data, Yngrid Pereira Marques

Theses - ALL

Although there have been many advances in regulations to assess flood risk in urban environments, the majority of these investigations to date have focused on fluvial or coastal flooding. However, in urban systems, pluvial flooding continues to be a pressing issue in need of attention. Due to the limited research on pluvial flooding in Syracuse, NY, its population and assets are exposed to the risks imposed by this type of flooding, as their primary metric for delineating flood risk is the traditional riverine flood zones designated by the Federal Emergency Management Agency (FEMA). To address this issue, this research implemented …

One-Bit Compressed Sensing In The Presence Of Noise, Swatantra Kafle

Dissertations - ALL

Many modern real-world systems generate large amounts of high-dimensional data stressing the available computing and signal processing systems. In resource-constrained settings, it is desirable to process, store and transmit as little amount of data as possible. It has been shown that one can obtain acceptable performance for tasks such as inference and reconstruction using fewer bits of data by exploiting low-dimensional structures on data such as sparsity. This dissertation investigates the signal acquisition paradigm known as one-bit compressed sensing (one-bit CS) for signal reconstruction and parameter estimation.

We first consider the problem of joint sparse support estimation with one-bit measurements …

Mitigating Insider Threat Risks In Cyber-Physical Manufacturing Systems, Jinwoo Song

Dissertations - ALL

Cyber-Physical Manufacturing System (CPMS)—a next generation manufacturing system—seamlessly integrates digital and physical domains via the internet or computer networks. It will enable drastic improvements in production flexibility, capacity, and cost-efficiency. However, enlarged connectivity and accessibility from the integration can yield unintended security concerns. The major concern arises from cyber-physical attacks, which can cause damages to the physical domain while attacks originate in the digital domain. Especially, such attacks can be performed by insiders easily but in a more critical manner: Insider Threats.

Insiders can be defined as anyone who is or has been affiliated with a system. Insiders have knowledge …

Effects Of Acid Deposition And Changing Climate On The Hydrochemistry And Critical Loads Of Watersheds In The Adirondack Region Of New York, Shuai Shao

Dissertations - ALL

Despite decreases in acidic deposition since the 1970s, the recovery of surface waters from acidification has been limited primarily due to the depletion of exchangeable base cations, net mineralization of organic sulfur and nitrogen and release of previously retained SO42- and NO3-, and increases in concentrations of naturally occurring organic acids from soil. The future recovery of stream chemistry from acidic deposition may be altered by projected increases in temperature and precipitation associated with a changing climate. The goals of this study were to conduct a modeling analysis of the response of soils and streams in the Adirondack Park, New …

#Blackgirlmathmagic: A Mixed Methods Study Examining African American Girls In Standardized Mathematicstesting, Rakeema Thomas Toussaint

LSU Doctoral Dissertations

Black women have been making successful strides in mathematics for decades; however, they continue to be underrepresented in mathematics and other STEM fields. According to Young et al. (2017), Black girls and women perform lower in mathematics than all other racial gender groups except for Black males. Considering the stakes for Black girls and women in mathematics, this study sought to address this group's challenges early in their secondary education experiences, focusing on standardized testing.

The purpose of this explanatory-sequential mixed-methods study was to determine how different mathematics item types impacted the performance of African American girls, especially multiple-select multiple-choice …

Introducing ‘Concept Question’ Writing Assignments Into Upper-Level Engineering Courses, Kirsten A. Davis, William A. Mogg, David P. Callaghan, Greg R. Birkett, David B. Knight, Katherine R. O'Brien

School of Engineering Education Faculty Publications

In this paper, we introduce ‘Concept Questions,’ a weekly writing assignment that has been incorporated into multiple upper-level engineering courses at a single university with the intent of enhancing students’ conceptual understanding of the course content. To explore the influence of this activity on students in these courses, we compared students’ scores on the Concept Question assignments with their final exam scores, analysed students’ open-ended responses to questions regarding their learning in the course, and surveyed students who had taken these courses in previous semesters to understand how the Concept Question assignments may have influenced their learning approaches in subsequent …

Real-Time Adaptive Sensor Attack Detection And Recovery In Autonomous Cyber-Physical Systems, Francis Akowuah

Dissertations - ALL

Cyber-Physical Systems (CPS) tightly couple information technology with physical processes, which rises new vulnerabilities such as physical attacks that are beyond conventional cyber attacks.Attackers may non-invasively compromise sensors and spoof the controller to perform unsafe actions. This issue is even emphasized with the increasing autonomy in CPS. While this fact has motivated many defense mechanisms against sensor attacks, a clear vision of the timing and usability (or the false alarm rate) of attack detection still remains elusive. Existing works tend to pursue an unachievable goal of minimizing the detection delay and false alarm rate at the same time, while there …

Augmented Human Machine Intelligence For Distributed Inference, Baocheng Geng

Dissertations - ALL

With the advent of the internet of things (IoT) era and the extensive deployment of smart devices and wireless sensor networks (WSNs), interactions of humans and machine data are everywhere. In numerous applications, humans are essential parts in the decision making process, where they may either serve as information sources or act as the final decision makers. For various tasks including detection and classification of targets, detection of outliers, generation of surveillance patterns and interactions between entities, seamless integration of the human and the machine expertise is required where they simultaneously work within the same modeling environment to understand and …

Development Of Computational Antibiotic Screening Platform Across Bacterial Outer Membrane Proteins, Yinghui Dai

Dissertations - ALL

Antibiotics are medicines used to treat bacterial infections by either killing bacteria or stopping them from reproducing. Throughout the use of antibiotics, bacteria has developed a variety of defense mechanisms against antibiotics and thus diminishing their effectiveness. Antibiotic resistance is a growing threat and becomes a global crisis as it is able to constantly evolve and rapidly spread. In the face of increasing bacterial resistance to all known antibiotics, there is an urgent need to accelerate the antibiotic discovery pipeline and discover new classes of antibiotics. A major bottleneck in the discovery of novel antibiotics is the limited permeability of …

Thriving In Student Affairs Professionals: An Exploration Of Supporting Constructs, Shawn Brodie, Phillip Campbell, Gretchen Day Fricke, Kawanna Leggett, Norris Manning

Dissertations

Student affairs professionals provide vital services to college students while also facing various challenges that impact their ability to thrive at work. This study examined overall thriving, its constructs and a set of predictors that impact thriving in student affairs professionals. Seligman’s (PERMA) theory of thriving provided the conceptual foundation for this study. Understanding the constructs that support thriving for student affairs professionals will help institutional leaders and professional organizations develop work environments and strategies that promote thriving. A global pandemic occurred during the time of this research, allowing exploration of how COVID-19 impacted thriving. This study also included variables …

Study Of Friction And Wear Effects In Aluminum Parts Manufactured Via Single Point Incremental Forming Process Using Petroleum And Vegetable Oil-Based Lubricants, Jose M. Diabb Zavala, Oscar Martinez-Romero, Alex Elias-Zuniga, Hector Manuel Leija Gutierrez, Alejandro Estrada-De La Vega, Jaime Taha-Tijerina

Manufacturing & Industrial Engineering Faculty Publications

This paper focuses on studying how mineral oil, sunflower, soybean, and corn lubricants influence friction and wear effects during the manufacturing of aluminum parts via the single point incremental forming (SPIF) process. To identify how friction, surface roughness, and wear change during the SPIF of aluminum parts, Stribeck curves were plotted as a function of the SPIF process parameters such as vertical step size, wall angle, and tool tip semi-spherical diameter. Furthermore, lubricant effects on the surface of the formed parts are examined by energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM) images, the Alicona optical 3D measurement system, …

Compact Sealed Spark Gaps, Seth Miller

Electrical and Computer Engineering ETDs

Spark gaps have always been a good solution for high power switching. They are simple, cheap, handle a large amount of Coulomb transfer, and are more forgiving to work with compared to solid-state alternatives. Even with solid-state switching advancing a long way since the 20th century, spark gaps outperform them in terms of peak power handling capabilities, Coulomb transfer, and make them attractive for higher power systems. Most lab settings use spark gaps because the cost is low, and they can be repaired if they break or wear out as opposed to a semiconductor alternative. While this technology is great …

Effect Of Nanoparticle And Acoustic Assisted Spalling On Iii-V Thin Film Photovoltaic Device Characteristics, David Smith

Theses

Thin film III-V photovoltaics (PV) are a high efficiency, low weight alternative to silicon. However, high costs make practical use cases limited to weight specific applications. These high costs are largely contained in material costs and especially thick substrates used as seed and handle layers for devices grown atop them. Removal and reuse of the substrates post device growth leads to a significant reduction in the material cost to make these devices. Acoustic assisted spalling (Sonic Wafering) is a low-cost substrate removal method that has the potential to significantly reduce costs related to the fabrication of III-V PVs. This thesis …

Examining The Factors Influencing The Mobile Learning Usage During Covid-19 Pandemic: An Integrated Sem-Ann Method, Khadija Alhumaid, Mohammed Habes, Said A. Salloum

All Works

The way in which the emotion of fear affects the technology adoption of students and teachers amid the COVID-19 pandemic is examined in this study. Mobile Learning (ML) has been used in the study as an educational social platform at both public and private higher-education institutes. The key hypotheses of this study are based on how COVID-19 has influenced the incorporation of mobile learning (ML) as the pandemic brings about an increase in different kinds of fear. The major kinds of fear that students and teachers/instructors are facing at this time include: fear because of complete lockdown, fear of experiencing …

Lipoprotein-Induced Increases In Cholesterol And 7-Ketocholesterol Result In Opposite Molecular-Scale Biophysical Effects On Membrane Structure, Manuela A.A. Ayee, Irena Levitan

Faculty Work Comprehensive List

Under hypercholesterolemic conditions, exposure of cells to lipoproteins results in a subtle membrane increase in the levels of cholesterol and 7-ketocholesterol, as compared to normal conditions. The effect of these physiologically relevant concentration increases on multicomponent bilayer membranes was investigated using coarse-grained molecular dynamics simulations. Significant changes in the structural and dynamic properties of the bilayer membranes resulted from these subtle increases in sterol levels, with both sterol species inducing decreases in the lateral area and inhibiting lateral diffusion to varying extents. Cholesterol and 7-ketocholesterol, however, exhibited opposite effects on lipid packing and orientation. The results from this study indicate …

Lyapunov Function-Based Stabilizing Control Scheme For Wireless Power Transfer Systems With Lcc Compensation Network, Abu Shahir Md Khalid Hasan

LSU Master's Theses

A stabilizing control scheme based on a Lyapunov function is proposed for wireless power transfer (or WPT) systems. A state-space model of the WPT system is developed and the Lyapunov function is formulated based on an energy equation of the system involving state variables. The internal resistance of a battery varies during charge and discharge. Therefore, if a WPT system is used to charge a battery, its output load will vary. Furthermore, the coupling coefficient between the transmitter (primary) and receiver (secondary) coils decreases when they are misaligned. Comparative case studies are conducted to verify the efficacy of the proposed …

Initial Investigations Into Tools For Phytoremediation Of Lead From Urban And Suburban Landscapes, Michael Taylor Bryant

LSU Master's Theses

Lead is a pervasive and ongoing problem in the landscape, especially in urban and suburban areas where historic use of tetraethyl lead gasoline and leaded paint has increased background amounts to dangerous levels. One method to solve this problem is the use of hyperaccumulator plant species, capable of concentrating over 1000 ppm Pb into their tissues. This is a slow process, even with hyperaccumulators, so the use of amendments to improve Pb solubility has gained popularity, though with mixed results. This study examined Trachelospermum asiaticum, Ardisia japonica, and Ophiopogon japonicus, three common landscape groundcovers used in Louisiana, …

Enhanced Oil Recovery In Tight Rocks Using The “Slot-Drill” Completion, Hassan Amer

LSU Master's Theses

Enhanced oil recovery (EOR) is essential in shale/tight formations because primary recovery typically produces less than 10% of the original hydrocarbon in-place (OHIP). This work presents a novel “slot-drill” EOR technology, which involves injecting gas through a horizontal fracture that is cut into the formation near the top of the reservoir (using a tensioned abrasive cutting cable mounted to the drillstring) and producing oil from a second slot-drilled horizontal fracture near the bottom of the reservoir.

The dusty-gas diffusion model was implemented in a compositional simulator to account for the diffusion mechanism expected during the injection of gases in this …

An Economical Method For Securely Disintegrating Solid-State Drives Using Blenders, Brandon J. Hopkins Phd, Kevin A. Riggle

Journal of Digital Forensics, Security and Law

Pulverizing solid-state drives (SSDs) down to particles no larger than 2 mm is required by the United States National Security Agency (NSA) to ensure the highest level of data security, but commercial disintegrators that achieve this standard are large, heavy, costly, and often difficult to access globally. Here, we present a portable, inexpensive, and accessible method of pulverizing SSDs using a household blender and other readily available materials. We verify this approach by pulverizing SSDs with a variety of household blenders for fixed periods of time and sieve the resulting powder to ensure appropriate particle size. Among the 6 household …

Load Flow Solution Of Distribution Systems - A Bibliometric Survey, K. V. S. Ramachandra Murthy, Vijay Kumar D, Lakshmi Kambhampati, Rayudu Srinivas, Rayudu Srinivas

Library Philosophy and Practice (e-journal)

In this paper, Bibliometric Survey has been carried out on ‘Load Flow Solution of Distribution Systems’ from 2012 to 2021. Scopus database has been used for the analysis. There were total 1711 documents found on this topic. The statistical analysis is carried out source wise, year wise, area wise, Country wise, University wise, author wise, and based on funding agency. Network analysis is also carried out based on Co-authorship, Co-occurrence. Results are presented. During 2020 and 2018, there were 263 documents published which is the highest. ‘IEEE Transactions on Power Systems’ has published 90 documents during the period of study …

Learning To Learn Variational Semantic Memory, Xiantong Zhen, Yingjun Du, Huan Xiong, Cees G.M. Snoek, Ling Shao

Machine Learning Faculty Publications

In this paper, we introduce variational semantic memory into meta-learning to acquire long-term knowledge for few-shot learning. The variational semantic memory accrues and stores semantic information for the probabilistic inference of class prototypes in a hierarchical Bayesian framework. The semantic memory is grown from scratch and gradually consolidated by absorbing information from tasks it experiences. By doing so, it is able to accumulate long-term, general knowledge that enables it to learn new concepts of objects. We formulate memory recall as the variational inference of a latent memory variable from addressed contents, which offers a principled way to adapt the knowledge …