Physical Sciences and Mathematics Commons^™

Improving White Dwarfs As Chronometers With Gaia Parallaxes And Spectroscopic Metallicities, Adam Moss, Ted Von Hippel, Elliot Robinson, Kareem El-Badry, David C. Stenning, David Van Dyk, Morgan Fouesneau, Coryn A.L. Bailer-Jones, Elizabeth Jeffery, Jimmy Sargent, Isabelle Kloc, Natalie Moticska

Publications

White dwarfs (WDs) offer unrealized potential in solving two problems in astrophysics: stellar age accuracy and precision. WD cooling ages can be inferred from surface temperatures and radii, which can be constrained with precision by high-quality photometry and parallaxes. Accurate and precise Gaia parallaxes along with photometric surveys provide information to derive cooling and total ages for vast numbers of WDs. Here we analyze 1372 WDs found in wide binaries with main-sequence (MS) companions and report on the cooling and total age precision attainable in these WD+MS systems. The total age of a WD can be further constrained if its …

Materialsatlas.Org: A Materials Informatics Web App Platform For Materials Discovery And Survey Of State-Of-The-Art, Jianjun Hu, Stanislav Stefanov, Yuqi Song, Sadman Sadeed Omee, Steph-Yves Louis, Edirisuriya M.D. Siriwardane, Yong Zhao, Lai Wei

Faculty Publications

The availability and easy access of large-scale experimental and computational materials data have enabled the emergence of accelerated development of algorithms and models for materials property prediction, structure prediction, and generative design of materials. However, the lack of user-friendly materials informatics web servers has severely constrained the wide adoption of such tools in the daily practice of materials screening, tinkering, and design space exploration by materials scientists. Herein we first survey current materials informatics web apps and then propose and develop MaterialsAtlas.org, a web-based materials informatics toolbox for materials discovery, which includes a variety of routinely needed tools for exploratory …

A Mathematical Model For The Adoption Of Information And Communication Technology In School Libraries In Nigeria, Helen Olubunmi Jaiyeola Akinade, Jeremiah Ademola Balogun, Peter Adebayo Idowu

Library Philosophy and Practice (e-journal)

This study focused on the development of a mathematical model required for estimating the number of adopters of ICT devices among libraries located in Nigeria. Data for this study was collected from 121 respondents selected based on a research survey approach using simple random sampling. 9 ICT devices were identified, namely: PCs, printers/fax machines, search engines, e-library systems, bulk SMS services, library management systems, bar/QR code readers, projectors and video conferencing. The results showed that the earliest ICT devices were adopted for use in 1997, such as: PCs, printers/fax machines and search engines. The remaining ICT devices were adopted in …

Sum Of Mobius Functions Over The Shifted Primes, Nelson Carella

Publications and Research

This article provides an asymptotic result for the summatory Mobius function ∑ p≤x μ(p + a) = O (x log−c x) over the shifted primes, where a ̸ = 0 is a fixed parameter, and c > 1 is a constant.

General Stochastic Calculus And Applications, Pujan Shrestha

LSU Doctoral Dissertations

In 1942, K. Itô published his pioneering paper on stochastic integration with respect to Brownian motion. This work led to the framework for Itô calculus. Note that, Itô calculus is limited in working with knowledge from the future. There have been many generalizations of the stochastic integral in being able to do so. In 2008, W. Ayed and H.-H. Kuo introduced a new stochastic integral by splitting the integrand into the adaptive part and the counterpart called instantly independent. In this doctoral work, we conduct deeper research into the Ayed–Kuo stochastic integral and corresponding anticipating stochastic calculus.

We provide a …

Energy Extraction From Black Holes, Alexandra Chanson

Student Research Symposium

I will discuss some background on black hole magnetohydrodynamics and then explore some recent results in higher-dimensional monopole power extraction

Cybersecurity And Threat Modeling, Kumar Setty

Computer Science Research Seminars and Symposia

An introduction to cybersecurity and threat modeling.

Advanced Communication And Sensing Protocols Using Twisted Light And Engineered Quantum Statistics, Michelle L. Lollie

LSU Doctoral Dissertations

Advanced performance of modern technology at a fundamental physical level is driving new innovations in communication, sensing capability, and information processing. Key to this improvement is the ability to harness the power of physical phenomena at the quantum mechanical level, where light and light-matter interactions produce technological advancement not realizable by classical means. Theoretical investigation into quantum computing, sensing capability beyond classical limits, and quantum information has prompted experimental work to bring state-of-the-art quantum systems to the forefront for commercial use. This dissertation contributes to the latter portion of the work. A set of preliminaries is included highlighting pertinent physical …

Sediment Buffering And Recycling On An Annual To Centennial Scale Along The Mississippi River, Nikki E. Neubeck

LSU Master's Theses

Although the Mississippi River and its tributaries have been investigated for many years, the alteration of the river through dams, levees, and diversions has affected how sediment is transported from source to sink (>10³ y). Previous provenance research using detrital zircon U-Pb dating indicates a slow transport time from source-to-sink, but recent anthropogenic alterations of the river may potentially diminish the transportation time of heavy minerals due to an increase in flow efficiency. The objective of this study is to analyze the degree of buffering and recycling of Mississippi River sediment over a range of short time scales, …

Early Solar System Chronology And Isotopic Linkage Of Non-Carbonaceous Chondrules, Clasts And Achondrites, Philip M. Reger

Electronic Thesis and Dissertation Repository

Chondrules are ubiquitous igneous spherules, the main constituents of ordinary chondrites, and are considered to be critical building blocks of planetesimals, yet their age and formation mechanism(s) remain debated. Differences between ages determined from the long-lived Pb-Pb and the short-lived ²⁶Al-²⁶Mg chronometers have been attributed to the heterogeneous distribution of ²⁶Al in the solar nebula, a radionuclide that was responsible for early differentiation of planetesimals.

To evaluate this hypothesis, the ²⁶Al-²⁶Mg and the ²⁰⁷Pb-²⁰⁶Pb isotopic compositions were both measured by multi-collector ICP-MS in individual chondrules and igneous clasts in unequilibrated …

Evaluating Gizzard Shad Dorosoma Cepedianum Populations In Two Kentucky Reservoirs Recently Invaded With Silver Carp Hypopthalmichthys Molitrix, Nathan Klein

Scholars Week

Gizzard Shad Dorosoma cepedianum are an ecologically important fish species found in many reservoirs throughout the southeastern United States such as Kentucky Lake and Lake Barkley. One current challenge that Gizzard Shad may face in these two reservoirs is competition with the invasive Silver Carp Hypophthalmichthys molitrix. However, quantifying the impacts of this competition may be difficult because of limited baseline population data for Gizzard Shad in these two reservoirs. The objective of this study is to describe size structure, condition, age, growth, mortality, and spawning potential of these two populations. Gizzard Shad were collected by boat electrofishing and …

Multimodal Multi-Head Convolutional Attention With Various Kernel Sizes For Medical Image Super-Resolution, Mariana-Iuliana Georgescu, Radu Tudor Ionescu, Andreea-Iuliana Miron, Olivian Savencu, Nicolae Verga, Nicolae-Cătălin Ristea, Fahad Shabaz Khan

Computer Vision Faculty Publications

Super-resolving medical images can help physicians in providing more accurate diagnostics. In many situations, computed tomography (CT) or magnetic resonance imaging (MRI) techniques output several scans (modes) during a single investigation, which can jointly be used (in a multimodal fashion) to further boost the quality of super-resolution results. To this end, we propose a novel multimodal multi-head convolutional attention module to super-resolve CT and MRI scans. Our attention module uses the convolution operation to perform joint spatial-channel attention on multiple concatenated input tensors, where the kernel (receptive field) size controls the reduction rate of the spatial attention and the number …

Asymptotic Mean-Value Formulas For Solutions Of General Second-Order Elliptic Equations, Pablo Blanc, Fernando Charro, Juan J. Manfredi, Julio D. Rossi

Mathematics Faculty Research Publications

We obtain asymptotic mean-value formulas for solutions of second-order elliptic equations. Our approach is very flexible and allows us to consider several families of operators obtained as an infimum, a supremum, or a combination of both infimum and supremum, of linear operators. The families of equations that we consider include well-known operators such as Pucci, Issacs, and k-Hessian operators.

Synthesis Of A Novel Carbon Monoxide-Releasing Gallium Flavonol Complex, Joel Ashton

Student Research Symposium

Carbon monoxide (CO) has unique therapeutic properties including anti-cancer effects. Flavonols such as 3-hydroxyflavone can release CO upon exposure to visible light. Gallium(III) also has anti-cancer properties and can replace Fe(III) in biological processes. This research was focused on synthesizing a complex of gallium(III) and 3-hydroxyflavone which can hopefully combine the anti-cancer properties of both gallium and CO. Initial attempts to synthesize the complex mimicked those of transition metal flavonol complexes using a base to deprotonate the flavonol and stirring with gallium salt. The most successful synthesis developed involved dissolving 3-hydroxyflavone and gallium nitrate in ethanol and DMSO, adjusting the …

Terrestrial Carbon Isotope Stratigraphy And Mammal Turnover During Post-Petm Hyperthermals In The Bighorn Basin, Wyoming, Usa, Sarah J. Widlansky, Ross Secord, Kathryn E. Snell, Amy E. Chew, William C. Clyde

Department of Earth and Atmospheric Sciences: Faculty Publications

Paleogene hyperthermals, including the Paleocene–Eocene Thermal Maximum (PETM) and several other smaller events, represent global perturbations to Earth’s climate system and are characterized by warmer temperatures, changes in floral and faunal communities, and hydrologic changes. These events are identified in the geologic record globally by negative carbon isotope excursions (CIEs), resulting from the input of isotopically light carbon into Earth’s atmosphere. Much about the causes and effects of hyperthermals remains uncertain, including whether all hyperthermals were caused by the same underlying processes, how biotic effects scale with the magnitude of hyperthermals, and why CIEs are larger in paleosol carbonates relative …

Evaluation Of Chelating Agents Used In Phytoextraction By Switchgrass Of Lead Contaminated Soil, Genna Hart, Marina Koether, Thomas C. Mcelroy, Sigurdur Greipsson

Faculty Open Access Publishing Fund Collection

Soil lead (Pb) contamination is a recognized environmental and global health problem. Phytoextraction of Pb using switchgrass (Panicum virgatum L.), a second-generation biofuel crop, is typically enhanced by soil chelation. The effectiveness of four different chelating agents, phytic acid (inositol hexaphosphate), citric acid, NTA (nitrilotriacetic acid), and EDTA (ethylenediaminetetraacetic acid) was examined in pot culture. Plants treated with EDTA (1 mM) showed significantly higher shoot Pb concentrations compared to control plants and plants treated with other chelates. Lead-solubility following phytoextraction was examined by soil washing using 0.01 and 0.05 M acetic acid as an extractant solution revealed no …

Wrapper And Hybrid Feature Selection Methods Using Metaheuristic Algorithms For English Text Classification: A Systematic Review, Osamah Mohammed Alyasiri, Yu N. Cheah, Ammar Kamal Abasi, Omar Mustafa Al-Janabi

Machine Learning Faculty Publications

Feature selection (FS) constitutes a series of processes used to decide which relevant features/attributes to include and which irrelevant features to exclude for predictive modeling. It is a crucial task that aids machine learning classifiers in reducing error rates, computation time, overfitting, and improving classification accuracy. It has demonstrated its efficacy in myriads of domains, ranging from its use for text classification (TC), text mining, and image recognition. While there are many traditional FS methods, recent research efforts have been devoted to applying metaheuristic algorithms as FS techniques for the TC task. However, there are few literature reviews concerning TC. …

Investigating Position 312 In Prmt1 For Future Fluorescent Labeling Studies, Sarah Nielson

Student Research Symposium

Protein arginine methyltransferase 1 (PRMT1) is an enzyme that post-translationally methylates other proteins in the cell. These methylation events play critical roles in maintaining cellular health. Labeling PRMT1 site-specifically will enable further research in PRMT1 oligomeric state in vivo and can be applied in future fluorescent studies. The intention of this research was to identify a position to label PRMT1 that does not affect oligomerization or activity. Position 312 was chosen as the site for specific tagging as it will have less interference in oligomerization, minimizes free rotation of fluorescent tags, and is surface-exposed. To confirm that position 312 was …

Isotopic Analysis Of Hydrous Phenocrysts In Lava Flows Of The Peruvian Altiplano Plateau: Testing For A Subduction Signature, Alyssa Schiwal

Student Research Symposium

The process of flat-slab subduction introduces fluids directly into the overlaying lithosphere, leaving behind a unique stable isotope and trace element signature to the surrounding crust/mantle. Fluid alteration of the deep lithosphere can help explain geologic processes that are observed at the surface, such as patterns of crustal deformation (mountain building) and volcanism. The young high-K mafic volcanic rocks found in the Altiplano region of Southern Peru are derived from the melting of an altered mantle source. By analyzing the hydrogen stable isotopes as well as the trace elements of these volcanic rocks we can locate the water source associated …

Modeling The Spread Of Curly Top Disease In Tomato Crops, Rachel Frantz

Student Research Symposium

Curly Top disease (CT), caused by a family of curtoviruses, infects a wide variety of agricultural crops. Historically, CT has caused extensive damage in tomato crops resulting in substantial economic loss for the tomato industry. Control methods for CT are scarce, and methods for predicting and assessing the scope of CT outbreaks are limited. In this paper, we formulate two theoretical models, a deterministic model and a stochastic model, for the spread of CT in a heterogeneous environment consisting of beets (preferred host) and tomatoes. The models are composed of two susceptible classes and two infected classes (infectious beets and …

Small-Scale “Atmospheric Perturbations” With A Horizontal Scale Of A Few Tens Of Meters, Jonas Hamrick

Student Research Symposium

The objective of this investigation isto identify and understand the small-scale atmospheric perturbations with a horizontal scale of a few tens of meters, based on a novel Na imager. These extremely small perturbations in this altitude range are believed to contribute considerably to the dynamics in the upper mesosphere and lower thermosphere, ranging between ~ 80 to 110 km. By changing the intensity of these Na images to mesospheric Na number density, we can derive the amplitudes of these perturbations based on the Na mixing ratios that provides a direct measure of the perturbation magnitudes. The perturbations of such scale …

Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien Devitt

Student Research Symposium

Atmospheric gravity waves (AGWs) that propagate up into the mesospheric region break and transfer energy into the region. This energy process affects seasonal temperatures in the mesosphere and has important implications for rocket launches and GPS satellites. Using the Utah State University (USU) Mesospheric Temperature Mapper (MTM) located at the Andes Lidar Observatory (ALO) in Chile (30°S), wave activity and seasonal temperature changes were studied over the Andes Mountain Range from Jan 2020 to the first few months of 2021 for this study. The primary goal of the whole project was to continue the long-term data collection and analysis (since …

Icon Satellite Measurements, Uncertainty, And Error Calculations, Benjamin Bradshaw

Student Research Symposium

NASA's satellite the Icon (Ionospheric Connections Explorer) is a satellite launched in 2019 to better understand the connection between Earth's atmosphere and the space environment. Though its systems were tested before launching further validation of its measurements are needed. This is accomplished through using USU's NA Lidar systems measurements over similar regions. USU's Na Lidar is a robust instrument that has been shown to be valid for many years. Through this comparison Icon's measurements have been shown to not be very precise at its lower measurements regions as it fails to measure a distinct temperature fluctuation around 92 km.

Manifold Alignment With Inter-Domain Diffusion, Andres Duque

Student Research Symposium

The integration of multimodal data presents a challenge in cases when the study of a given phenomena by different instruments or conditions generates distinct but related domains. In this paper, we propose Diffusion Transport Alignment (DTA) a semi-supervised manifold alignment method that exploits prior correspondence knowledge between distinct data views. DTA finds a bijection between two domains, which by assumption, share a similar geometrical structure coming from the same underlying data generating process. We empirically demonstrate the effectiveness of our method to integrate multimodal data, as well as how it can improve the performance of machine learning tasks, otherwise less …

The Outdoor Fashion Industry Is Not Sustainable, Joshua Hillam

Student Research Symposium

Outdoor fashion companies are responsible for a large amount of waste and pollution worldwide. I believe they are ethically bound to make changes in their manufacturing process to decrease their footprint because their products are used in outdoor environments that are impacted negatively by waste and pollution. The fashion industry as a whole is responsible for 10% of the carbon emissions worldwide. Research was conducted by first understanding what being sustainable means from the EPA, from individuals who work in the fashion industry, and from companies that advocate for more sustainable clothing. I then investigated what materials are the most …

Analyzing Suicidal Text Using Natural Language Processing, Cassandra Barton

Student Research Symposium

Using Natural Language Processing (NLP), we are able to analyze text from suicidal individuals. This can be done using a variety of methods. I analyzed a dataset of a girl named Victoria that died by suicide. I used a machine learning method to train a different dataset and tested it on her diary entries to classify her text into two categories: suicidal vs non-suicidal. I used topic modeling to find out unique topics in each subset. I also found a pattern in her diary entries. NLP allows us to help individuals that are suicidal and their family members and close …

Can Superoxide-Responsive Co Delivery Molecules Be Developed?, Taylor Dittmar

Student Research Symposium

Although known for its toxicity, carbon monoxide (CO) has now been identified as producing beneficial health effects when present at low concentrations. CO is generated in the human body during the breakdown of heme. It is known for its anti-cancer, cardioprotective, and anti-inflammatory effects. To enhance these therapeutic effects, CO delivery molecules have been developed. Fluorescent flavonol-based CO delivery molecules are gaining broad interest due to their triggerable, trackable, and targetable properties. Flavonols can also be used as dual functioning molecules, with additional capabilities such as the detection of reactive oxygen species (ROS) being possible to incorporate in addition to …

Does Cannabidiol Affect The Physical Properties Of Anhydrous Milk Fat And Palm Kernel Oil?, Joseph Cooney

Student Research Symposium

As cannabidiol (CBD) is added to more and more foods, it becomes increasingly important to study the effects that this CBD has on the physical properties of the lipids in which they are dissolved, which is the objective of this study. The viscosity, hardness, melting profile, crystal size, and solidification over time are studied for anhydrous milk fat (AMF) and palm kernel oil (PKO). Concentrations by mass of 1% and 2.5% CBD are added to each lipid, and these concentrations are tested against a pure lipid control. AMF is crystallized at 26 C, and PKO is crystallized at 22 C …

Seasonal Variations In Global Ionospheric Total Electron Content (Tec), Jason Knudsen

Student Research Symposium

As the Sun ionizes atoms and molecules in the Earth’s ionosphere, the region of atmosphere above approximately 100 km in altitude, the created ionization in this region affects many of the systems that we rely on in daily life. This includes cellular service, GPS navigation, weather forecasting, and credit card data. A good measure for the level of ionization in the ionosphere is the total electron content (TEC), which is the number of electrons in a one square meter column above a given location. The TEC over a geographic location influences the propagation of radio waves that traverse that section …

Hidden Symmetries In Black Holes, Luis Fernando Temoche

Student Research Symposium

Our objective is to show the existence of conformal symmetries in rotating black hole solutions near its event horizon. To do so, we are going to study the cases of both Kerr BH and 5D Myers-Perry BH. In particular, by applying certain coordinate transformations, we will be able exploit this conformal invariance from its geometry as well as the dynamics of scalar fields propagating on this particular background. The invariance allows as to describe strongly coupled systems, conformal field theories to be specific, in lower dimensions.