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Full-Text Articles in Physical Sciences and Mathematics

Growth, Lipid Production And Biodiesel Potential Of Chromulina Freiburgensis Dofl., An Acidophilic Chrysophyte Isolated From Berkeley Pit Lake, June E. Mohler Mitman Mar 2109

Growth, Lipid Production And Biodiesel Potential Of Chromulina Freiburgensis Dofl., An Acidophilic Chrysophyte Isolated From Berkeley Pit Lake, June E. Mohler Mitman

Graduate Theses & Non-Theses

Microalgae remain a promising, but underdeveloped source of lipids for sustainable biodiesel. Some of the obstacles to cost-effective commercial-scale production have been culture contamination and expensive harvest methods. A chrysophyte isolated from Berkeley Pit Lake and identified as Chromulina freiburgensis, was found to grow rapidly in a pH 2.5 liquid medium and to amass numerous intracellular lipid bodies. This research addresses the scarcity of published knowledge on the topic of chrysophyte species as potential lipid sources for biodiesel. It investigates how growth phase, culture conditions, and harvest timing influence the quantity and composition of lipids produced by this alga ...


Quantification Of Hydrologic Response To Forest Disturbance In Western U.S. Watersheds, Sara A. Goeking Aug 2022

Quantification Of Hydrologic Response To Forest Disturbance In Western U.S. Watersheds, Sara A. Goeking

All Graduate Theses and Dissertations

Forested watersheds produce more than half of the water supply in the United States. Forests affect how precipitation is partitioned into available water versus evapotranspiration. This dissertation investigated how water yield and snowpack responded to forest disturbance following recent disturbances in western U.S. forests during the period 2000-2019.

Chapter 2 systematically reviewed 78 recent studies that examined how water yield or snowpack changed after forest disturbances. Water yield and snowpack often increased after disturbance, but decreased in some circumstances. Decreased water yield was most likely to occur following disturbances that did not remove the entire forest canopy. It was ...


Predicting Order Status Using Xgboost, Kegan J. Penovich Aug 2022

Predicting Order Status Using Xgboost, Kegan J. Penovich

All Graduate Plan B and other Reports

Invista, a Koch subsidiary, is a multinational producer of fibers, resins, and intermediaries, particularly nylon. To keep the company operating required them to take over 1.5 million orders over the course of - years, less than a third of which arrived on-time. Orders arriving other than when expected can cause many problems for any company. While arriving late is a clear problem, it also troublesome for them to arrive early. In the face of this, it becomes important to be able to tell a-priori if an order will arrive on-time or not.

To address this problem, we made use of ...


Analytic Solution Of 1d Diffusion-Convection Equation With Varying Boundary Conditions, Malgorzata B. Glinowiecka-Cox Jun 2022

Analytic Solution Of 1d Diffusion-Convection Equation With Varying Boundary Conditions, Malgorzata B. Glinowiecka-Cox

University Honors Theses

A diffusion-convection equation is a partial differential equation featuring two important physical processes. In this paper, we establish the theory of solving a 1D diffusion-convection equation, subject to homogeneous Dirichlet, Robin, or Neumann boundary conditions and a general initial condition. Firstly, we transform the diffusion-convection equation into a pure diffusion equation. Secondly, using a separation of variables technique, we obtain a general solution formula for each boundary type case, subject to transformed boundary and initial conditions. While eigenvalues in the cases of Dirichlet and Neumann boundary conditions can be constructed easily, the Robin boundary condition necessitates solving a transcendental algebraic ...


Shadows Of A Schwarzschild Black Hole Surrounded By A Spherically Symmetric Dark Matter, Ahmad Ibrahim Jun 2022

Shadows Of A Schwarzschild Black Hole Surrounded By A Spherically Symmetric Dark Matter, Ahmad Ibrahim

Theses and Dissertations

In this thesis, using general relativity, the null geodesics and black hole shadow of a spherically symmetric configuration of a black hole (surrounded by a dark matter shell) are studied. First, the standard

results of the photon sphere of Schwarzschild de-Sitter black hole is revisited and analyzed more carefully. Secondly, using an ansatz (piecewise metric function) commonly used in the literature to describe the mass distribution of the spherically symmetric black hole - dark matter configuration, the null geodesics through vacuum and dark matter are analyzed. Assuming an observer located at a finite distance from the black hole outside the dark ...


Enhancing Vanadium Redox Battery Performance Using Tungsten-Bismuth-Based Oxide Nanostructures As Electrode Modifiers, Taher Al Najjar Jun 2022

Enhancing Vanadium Redox Battery Performance Using Tungsten-Bismuth-Based Oxide Nanostructures As Electrode Modifiers, Taher Al Najjar

Theses and Dissertations

Renewable energy power plants require high efficiency conversion and storage systems that can store high amounts of energy and can be integrated with the electrical grid. Vanadium redox flow batteries are very promising for this application. However, one major drawback of VRFBs is their low power density which means that right now they cannot replace non-renewable energy sources. Different carbon materials are used as electrodes in VRFBs and each carbon material affects the battery’s performance in a different way. Modification of these electrodes can increase the power density of the battery. Some metal oxides like tungsten oxide can enhance ...


Exploring The Effectiveness Of Multiple-Exemplar Training For Visual Analysis Of Ab-Design Graphs, Verena S. Bethke Jun 2022

Exploring The Effectiveness Of Multiple-Exemplar Training For Visual Analysis Of Ab-Design Graphs, Verena S. Bethke

Dissertations, Theses, and Capstone Projects

In behavior analysis, data are usually analyzed using visual analysis of the graphed data. There are a wide range of methods used to visually analyze data, from a basic ‘textbook’ style approach to the use of visual aids, decision-rubrics, and computer-based approaches. In the literature, there have been some comparisons of the efficacy of different approaches. Visual analysis as a behavior can be taught using a variety of methods, independent of how the skill itself is to be performed. Teaching methods include lecture, online instruction, and equivalence-based instruction. There is not much research on the teaching of visual analysis specifically ...


The Zariski-Riemann Space As A Universal Model For The Birational Geometry Of A Function Field, Giovan Battista Pignatti Morano Di Custoza Jun 2022

The Zariski-Riemann Space As A Universal Model For The Birational Geometry Of A Function Field, Giovan Battista Pignatti Morano Di Custoza

Dissertations, Theses, and Capstone Projects

Given a function field $K$ over an algebraically closed field $k$, we propose to use the Zariski-Riemann space $\ZR (K/k)$ of valuation rings as a universal model that governs the birational geometry of the field extension $K/k$. More specifically, we find an exact correspondence between ad-hoc collections of open subsets of $\ZR (K/k)$ ordered by quasi-refinements and the category of normal models of $K/k$ with morphisms the birational maps. We then introduce suitable Grothendieck topologies and we develop a sheaf theory on $\ZR (K/k)$ which induces, locally at once, the sheaf theory of each normal ...


Symmetries, Zero Modes And Light Transport In Non-Hermitian Photonics, Jose David Hernandez Rivero Jun 2022

Symmetries, Zero Modes And Light Transport In Non-Hermitian Photonics, Jose David Hernandez Rivero

Dissertations, Theses, and Capstone Projects

We approach some fundamental aspects of photonic dissipative systems treated by a non-Hermitian theory. Inspired by the possibilities provided by some major non-Hermitian symmetries, we study systematically the properties of the novel pseudochirality, pseudo-anti-Hermiticity, and supersymmetry. We analyze other aspect of photonics, the zero mode, which has a profound connection to non-Hermitian physics. We propose a scheme to realize a zero mode that exists even in the absence of symmetries. Finally, we approach light transport in non-Hermitian photonic systems, where the introduction of gain and loss can modify drastically the propagation speed of wavepackets.


Phase Transitions, Critical Phenomena, And Correlation Functions In The 2d Ising Model And Its Applications To Quantum Dynamics: A Tensor Network Approach, Sankhya Basu Jun 2022

Phase Transitions, Critical Phenomena, And Correlation Functions In The 2d Ising Model And Its Applications To Quantum Dynamics: A Tensor Network Approach, Sankhya Basu

Dissertations, Theses, and Capstone Projects

This thesis explores several aspects of the 2D Ising Model at both real and complex temperatures utilizing tensor network algorithms. We briefly discuss the importance of tensor networks in the context of forming efficient representations of wavefunctions and partition functions for quantum and classical many-body systems respectively, followed by a brief review of the tensor network renormalization algorithms to compute the one point and two point correlation functions. We use the Tensor Renormalization Group (TRG) to study critical phenomena and examine feasibility of accurate estimations of universal critical data for three critical points for three critical points in two dimensions ...


Optical Studies Of Wide Bandgap Photonic Materials, Nikesh Maharjan Jun 2022

Optical Studies Of Wide Bandgap Photonic Materials, Nikesh Maharjan

Dissertations, Theses, and Capstone Projects

In this dissertation work, optical properties of wide bandgap materials such as hexagonal Boron Nitride (h-BN) and Zinc Oxide (ZnO) have been studied. Deep UV photoluminescence spectroscopy was employed to study the optical properties of bulk h-BN and powder crystals using a laser of wavelength 200 nm, which is the fourth harmonic of Ti:Sapphire laser as excitation source. The properties and chemical compositions of annealed and unannealed bulk h-BN were investigated. The PL spectra from h-BN samples annealed at 900 ºC in ambient air, had strong phonon assisted band edge emissions along with a sharp atomic-like emission line at ...


Understanding Coastal And Inland Hydrometeorological Hazards Produced By Extratropical And Tropical Cyclones Along The East Coast Of The United States, Katherine Towey Jun 2022

Understanding Coastal And Inland Hydrometeorological Hazards Produced By Extratropical And Tropical Cyclones Along The East Coast Of The United States, Katherine Towey

Dissertations, Theses, and Capstone Projects

As global temperatures continue to rise, the effects of anthropogenic climate change will impact the magnitude and frequency of pluvial, fluvial, and coastal flooding events. If we want to accurately predict changes in these flooding events, we need to fully understand them in the current climate. As such, this research examines the relationship between hydrometeorological hazards and the characteristics of the storm types, such as extratropical cyclones (ETCs) and tropical cyclones (TCs), that produce such hazards. Through the use of observational and reanalysis data, the work herein utilizes a cyclone-hazard association algorithm and extreme value analysis to assess the extent ...


Coded Distributed Function Computation, Pedro J. Soto Jun 2022

Coded Distributed Function Computation, Pedro J. Soto

Dissertations, Theses, and Capstone Projects

A ubiquitous problem in computer science research is the optimization of computation on large data sets. Such computations are usually too large to be performed on one machine and therefore the task needs to be distributed amongst a network of machines. However, a common problem within distributed computing is the mitigation of delays caused by faulty machines. This can be performed by the use of coding theory to optimize the amount of redundancy needed to handle such faults. This problem differs from classical coding theory since it is concerned with the dynamic coded computation on data rather than just statically ...


A New Insight Into Fungal Cell Wall Architecture By Functional Genomics And Solid-State Nmr Along With Recent Advancements In Dynamic Nuclear Polarization For Analyzing Biomolecules, Arnab Chakraborty May 2022

A New Insight Into Fungal Cell Wall Architecture By Functional Genomics And Solid-State Nmr Along With Recent Advancements In Dynamic Nuclear Polarization For Analyzing Biomolecules, Arnab Chakraborty

LSU Master's Theses

This dissertation summarizes the findings related to the way by which supramolecular architecture of fungal cell wall changes with genetic mutation, dispensing genes responsible for biosynthesis of cell wall polysaccharides. This is necessary because without perfect picture of how supramolecular assembly changes with genetic mutation it is hard to assess new anti-fungal targets. Alongside this we have highlighted how recent advancement into Dynamic Nuclear Polarization (DNP) methods improved characterization of biomolecules both in case of labeled and unlabeled samples.

First study utilized Solid-state NMR (SSNMR) which is a non-destructive technique hence enabled us for the first time to deduce how ...


Microplastics In Our Oceans May Inhibit Aerosols From Cooling The Atmosphere, Michael Rafla May 2022

Microplastics In Our Oceans May Inhibit Aerosols From Cooling The Atmosphere, Michael Rafla

Undergraduate Honors Theses

Sea spray aerosol (SSA) are liquid gaseous particles emitted directly from the ocean, making their way into the atmosphere. It is hypothesized that SSA enters the atmosphere from mechanical processes such as wind and ocean waves. Winds and waves promote bubble formation and these bubbles which make their way onto the ocean surface. After these wave-created bubbles rise to the ocean surface, the bubble ruptures and water evaporates which causes gaseous drops to be released into the air: this is the main source of SSA. SSA matter is known to affect Earth’s climate, by scattering light energy and solar ...


Extending The Application Of Polyol-Induced Extraction For The Analysis Of Glucocorticoids And Nsaids In Water Using Uhplc-Ms/Ms, Shipra Patel May 2022

Extending The Application Of Polyol-Induced Extraction For The Analysis Of Glucocorticoids And Nsaids In Water Using Uhplc-Ms/Ms, Shipra Patel

Seton Hall University Dissertations and Theses (ETDs)

Polyol induced extraction (PIE) is an extraction technique developed and patented by Sowa Jr., Murphy, and Deshpande at Seton Hall University as a method of removal of water from acetonitrile. PIE is a technique that separates water from a mixture containing an organic liquid and water by adding a polyol to the mixture that leads to phase separation of aqueous and organic phase. The goal of this work was to extend the application of PIE and to demonstrate that PIE can be an alternative method for extraction of glucocorticoids and non-steroidal anti-inflammatory drugs (NSAIDS) which then can be analyzed using ...


Accessing The Ecosphere: An Indoor Nature-Based Community Expressive Arts Therapy (Exat) Exploration Project, Heather Powers May 2022

Accessing The Ecosphere: An Indoor Nature-Based Community Expressive Arts Therapy (Exat) Exploration Project, Heather Powers

Expressive Therapies Capstone Theses

This capstone thesis posits that when humans connect and maintain a relationship with nature, their mental health improves. Humans have developed from and within Earth’s ecosystem, making our relationship with nature a necessary acknowledgement that the self is more than a corporeal body but is, in fact, embedded within the natural world around us. The current overwhelming dependence on electronic advancements and the development of urban areas have led people to become more distant in their relationship to nature, putting the overall well-being of the planet in jeopardy. This thesis points out that the more separation we feel from ...


Corporate Social Responsibility In The Information Technology Industry, Natalie Louise Calhoun May 2022

Corporate Social Responsibility In The Information Technology Industry, Natalie Louise Calhoun

Master's Projects and Capstones

Information technology companies contribute to greenhouse gas emissions via data servers, office administrative operations, and manufacturing of hardware components. Corporate Social Responsibility programs are a voluntary method of tracking and reducing negative environmental impacts. The 2019 Corporate Social Responsibility data from four Bay Area (California, USA) information technology companies (Adobe, Cisco, Salesforce, and Nvidia) all listed in sustainable index funds were compared to determine best reporting standards. The data analysis also allowed for research into how carbon emissions are categorized and reported on, and which emissions companies pay attention to through Corporate Social Responsibility projects. The physical ownership responsibility for ...


Formal And Informal Styles Of Clothing In The Assessment Of Female Political Candidates, Erma Kurtovic May 2022

Formal And Informal Styles Of Clothing In The Assessment Of Female Political Candidates, Erma Kurtovic

Master's Theses

Abstract: This study will research the importance of dress code of female candidates on the confidence in leadership.The research question is: How Important is the Formality of Dress Code in the Assessment of Leadership of Female Political Candidates? It is addressed by using an experimental design carried out in India and the United States, using Qualtrics and Amazon Mechanical Turk. This research gathered 400 responses, 200 from each country. Primary data collection was used, with the implementation of two experiments. The experimental design of the two experiments consisted of two conditions, one in which the main political candidate is ...


In-Phantom Film Measurements Of Two Treatment Planning Systems For Single-Fraction Spine Sbrt, Michael J. Taylor May 2022

In-Phantom Film Measurements Of Two Treatment Planning Systems For Single-Fraction Spine Sbrt, Michael J. Taylor

LSU Master's Theses

Purpose: Treatment planning accuracy for spine stereotactic body radiation therapy (SBRT) varies depending on the dose calculation algorithm utilized in the treatment planning system (TPS). This project compared the end-to-end accuracy between spine SBRT plans calculated in a convolution-superposition based TPS (TPSCS) and Monte Carlo based TPS (TPSMC) with radiochromic film measurements. The hypothesis was that TPSMC would calculate the dose gradient in the critical region between the vertebral body and the spinal cord more accurately than TPSCS.

Methods: Single-fraction spine SBRT treatments following RTOG 0631 and local institutional guidelines were planned in TPSCS and ...


Changes In Heat Metrics Following A Major Hurricane And Implications On Heat Stress, Cade Reesman May 2022

Changes In Heat Metrics Following A Major Hurricane And Implications On Heat Stress, Cade Reesman

LSU Master's Theses

Tropical cyclones modify surface-atmosphere interactions in several ways, including the destruction of patches of tree canopy, increasing the direct and diffuse (shortwave) radiation reaching the surface. This addition of radiation at the surface impacts the sensible, latent, and substrate heat (energy) fluxes, generating heat anomalies along the hurricane’s track, which, among other effects, contributes to the higher post-hurricane surface air temperatures. This study consists of a case study on Hurricane Laura (2020) to examine hurricane defoliation impacts on heat stress metrics. Normalized difference vegetation index (NDVI) data from NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) identified the spatial extent ...


Echoed Sites And The Unknowable Object, Joseph Canizales May 2022

Echoed Sites And The Unknowable Object, Joseph Canizales

MFA in Visual Art

This thesis will discuss the expanded field of sculpture, simulacra, digital technology, and two terms I’ve devised: the unknowable object, and echoed sites. Within these two terms, I’m concerned with the complicated relationship between humans and geology and how we extract material from the ground without reflecting on the geologic history of the site. In echoed sites I create sculptures with and without a geologic site or object, by way of digital technology. These forms display two states paradoxically in balance, where what’s presented leaves more questions than answers. Thus, as part of echoed sites, exists the ...


Information Provenance For Mobile Health Data, Taylor A. Hardin May 2022

Information Provenance For Mobile Health Data, Taylor A. Hardin

Dartmouth College Ph.D Dissertations

Mobile health (mHealth) apps and devices are increasingly popular for health research, clinical treatment and personal wellness, as they offer the ability to continuously monitor aspects of individuals' health as they go about their everyday activities. Many believe that combining the data produced by these mHealth apps and devices may give healthcare-related service providers and researchers a more holistic view of an individual's health, increase the quality of service, and reduce operating costs. For such mHealth data to be considered useful though, data consumers need to be assured that the authenticity and the integrity of the data has remained ...


The Impact Of Academic Tracking And Mathematics Self-Concept On Mathematics Achievement., Kain M. Schow May 2022

The Impact Of Academic Tracking And Mathematics Self-Concept On Mathematics Achievement., Kain M. Schow

Dissertations, Theses, and Projects

ABSTRACT

This study examines the effects of academic tracking, in high school math, on students’ mathematics self-concept (MSC) and how that correlates to students’ mathematics achievement. This study measured students’ MSC through a mathematics self-concept questionnaire and measured mathematics achievement by the students’ latest grade report. Participants included 60 students in grades 10-12 who had been or were currently enrolled in math courses in the researcher’s school district. The data collected will direct the researcher and school administration on the effects of academic tracking on students, allowing for further discussion about continuing tracking in the district.


A Quantitative Study Of An Online Learning Platform’S Impact On High School Students' Engagement, Academic Achievement, And Student Satisfaction In A Mathematics Class, Mariah Minkkinen May 2022

A Quantitative Study Of An Online Learning Platform’S Impact On High School Students' Engagement, Academic Achievement, And Student Satisfaction In A Mathematics Class, Mariah Minkkinen

Dissertations, Theses, and Projects

The present study investigated the impact using the online learning platform Pear Deck had on an online high school math class. The study measured student engagement, academic achievement, and students’ overall satisfaction with using the online learning platform. The participants in this study were online Algebra 2 students. The study was conducted during synchronous online lessons using an online learning system. Data was collected from two different live classes. One class used the online learning platform Pear Deck and the other did not. Engagement was measured by charting the number of student responses for each question posed. Students’ academic achievement ...


Sheltered Math Curriculum For Middle School English Learners, Jasmine Ercink May 2022

Sheltered Math Curriculum For Middle School English Learners, Jasmine Ercink

Dissertations, Theses, and Projects

Language barriers have shown a need for differentiation and sheltered instruction in the classroom for English Learners (ELs) to be successful in the United States public school system. This project proposes a mathematics curriculum using SIOP so that both groups of students in the middle school level can increase their proficiency in the mathematics content area as well as experience opportunities for academic and social language development. The purpose of this report is to describe the processes, methods, data, and intent of the mathematics curriculum for these learners. The curriculum acts as an effective intervention to fill gaps in both ...


The Identification And Quantification Of Organophosphate Flame Retardants In Raw Materials Utilized In Polyurethane Production, Lindsay Tudor May 2022

The Identification And Quantification Of Organophosphate Flame Retardants In Raw Materials Utilized In Polyurethane Production, Lindsay Tudor

Master of Science in Chemical Sciences Theses

Flame retardant additives are utilized in various polyurethane applications to comply with industry and flammability standards. Federal regulations and restrictive standards continue to tighten controls on certain impurities found in flame retardant blends. These restrictions include the limitation of organophosphates. Extensive research has been conducted to examine the effects of organophosphates in humans. To date, researchers have predominantly focused on the final product, mainly furniture and bedding products, rather than the raw materials utilized in production. Industrial chemists continue to grapple with the development of an effective method for detecting and quantifying organophosphate compounds in various flame retardant mixtures as ...


Characterization Of Bimetallic Silver-Copper Nanoinks With Hydroxyethyl-Cellulose Additives, Daniel Brunick May 2022

Characterization Of Bimetallic Silver-Copper Nanoinks With Hydroxyethyl-Cellulose Additives, Daniel Brunick

Undergraduate Honors Theses

Coinage metal nanoparticles remain an intriguing subject for research due to their industrial versatility. Primary applications of coinage metal nanoparticles include printed electronics, solar panels, and sensors. Inks formulated with the nanoparticles are conductive and thus useful for fabricating sensors. Silver-copper nanoalloy inks are viable for the fabrication of flexible sensing devices for the detection of volatile organic compounds. One of the challenges is the ability to synthesize composition-controllable alloy nanoparticles at room temperature through wet chemical methods and achieve controllable sintering at room temperature. This work addresses the challenges by investigating the room-temperature synthesis of silver-copper alloy nanoparticles and ...


Sustainable Rural Development: Is It Possible To Boost Rural Economies While Protecting The Environment?, Jack M. Hempleman May 2022

Sustainable Rural Development: Is It Possible To Boost Rural Economies While Protecting The Environment?, Jack M. Hempleman

Undergraduate Theses, Capstones, and Recitals

Amidst rapid depletion of our carbon budget, the need to change our practices to be more in line with Earth’s limits has become important in every sector of our economy. From advances in renewable energy generation to the growth of urban gardening, people around the world are taking action to change the way they interact with our planet. However, growing concerns have been raised that protections for the environment will disproportionately harm struggling communities. For instance, rural communities in the United States already exhibit disproportionately high poverty rates, income inequality, and unemployment, as well as lower quality healthcare and ...


Optimization Of Paper-Based Substrates For Surface Enhanced Raman Spectroscopic Biosensor Development, Kaylee M. Cappuccio May 2022

Optimization Of Paper-Based Substrates For Surface Enhanced Raman Spectroscopic Biosensor Development, Kaylee M. Cappuccio

Undergraduate Honors Theses

Advancements in the field of analytical chemistry have greatly expanded the development of biosensors for the detection of a wide array of diseases. This study aims to optimize an affordable paper-based nanocomposite biosensor that utilizes surface-enhanced Raman spectroscopy (SERS). Specifically, it investigates the preparation parameters for a paper-based SERS substrate, including nanoparticle administration and drying procedures. A particular focus of this work is to assess how the wax-defined paper channels can effectively enhance SERS intensity. The results revealed that while the wax-printed wells can define the nanoparticle administration for SERS detection, wax backing may reduce the sensitivity of SERS by ...