Digital Commons Network^™

Branched-Chain Amino Acids And Their Interactions With Lipid Metabolites For Increased Risk Of Gestational Diabetes, Ninghua Li, Jing Li, Hui Wang, Jinnan Liu, Weiqin Li, Kai Yang, Xiaoxu Huo, Junhong Leng, Zhijie Yu, Gang Hu, Zhongze Fang, Xilin Yang

Population and Public Health Science Faculty Publications

Objective: We aimed to explore associations of branched-chain amino acids (BCAA) in early pregnancy with gestational diabetes mellitus (GDM), and whether high BCAAs and lipidomics markers had interactive effects on the risk of GDM. Methods: We conducted a 1:1 case-control study (n=486) nested in a prospective cohort of pregnant women in Tianjin, China. Blood samples were collected at their first antenatal care visit (median 10 gestational weeks). Serum BCAAs, saturated fatty acids (SFA) and lysophosphatidylcholines (LPC) were measured by liquid chromatography-tandem mass spectrometry analysis. Conditional logistic regression was performed to examine associations of BCAAs with the risk of GDM. Interactions …

Ignoring Spatial And Spatiotemporal Dependence In The Disturbances Can Make Black Swans Appear Grey, R. Kelley Pace, Raffaella Calabrese

Faculty Publications

Automated valuation models (AVMs) are widely used by financial institutions to estimate the property value for a residential mortgage. The distribution of pricing errors obtained from AVMs generally show fat tails (Pender 2016; Demiroglu and James Management Science, 64(4), 1747–1760 2018). The extreme events on the tails are usually known as “black swans” (Taleb 2010) in finance and their existence complicates financial risk management, assessment, and regulation. We show via theory, Monte Carlo experiments, and an empirical example that a direct relation exists between non-normality of the pricing errors and goodness-of-fit of the house pricing models. Specifically, we provide an …

An Evaluation Of Hemp Cultivation Practices And Cannabinoid Analysis In South Louisiana, Kaylee M. Deynzer

LSU Master's Theses

Hemp (Cannabis sativa L.) cultivation research did not exist in Louisiana prior to 2020 (LSU AgCenter Therapeutic Cannabis Committee, 2020). Therefore, nine cultivars of essential oil-type hemp were evaluated in 2020 and 2021 to determine optimum planting dates, in-row plant spacings and THC compliancy for organic field production in south Louisiana. Until suitable genetics for Louisiana’s environment can be identified, an in-row spacing of three feet is recommended for field-grown hemp. Cultivars Berry Blossom, Queen Dream and Stormy Daniels produced sufficient biomass for commercial production. While Berry Blossom, Queen Dream, Oregon White and Putin’s Problem were high-yielding, Oregon White …

Southwest Pacific Tropical Cyclone Development Classification Utilizing Machine Learning And Synoptic Composites, Rupsa Bhowmick, Jill C. Trepanier, Alex M. Haberlie

Faculty Publications

This study evaluates the ability of machine learning algorithms to classify tropical depressions (TDs) and tropical storms (TSs) in the western region of the southwest Pacific Ocean (SWPO). Decision rules are generated to predict the environment required for a depression to fully develop into a mature storm, and the most influential predictors in the classification decision are ranked. TD and TS are discriminated based on a maximum sustained wind speed threshold (≥17 ms−1). Various aerosol, thermodynamic, and dynamic parameters are extracted closest to the initiation point of each non-developing and developing sample. The covariates associated with each labelled sample are …

Validation Of The Guess-18 For The Usability Of A Virtual Reality Racing Game, William A. Carman

LSU Master's Theses

Virtual reality (VR) technology has been in development for many decades, with recent strides in the consumer market. Head-mounted displays (HMDs) provide an immersive VR experience by inserting users into an artificially constructed digital world. However, there is currently no standardized tool for measuring the usability of a VR system or environment. The GUESS-18 is a validated usability questionnaire designed for measuring the usability of video games with 9 factors present in video games. The objective of this study was to validate the GUESS-18 for measuring the usability of VR in a gaming environment.

Participants played Assetto Corsa, a racing …

Exploring Toluene Biosynthesis In Microbial Consortia Derived From Sediments And Superfund Site Groundwater, Raymond J. Poche

LSU Master's Theses

While the aromatic hydrocarbon toluene is widely regarded as a contaminant associated with discharges of crude oil and refined petroleum products (e.g., gasoline), the enzyme phenylacetate decarboxylase catalyzes the decarboxylation of phenylacetate to yield toluene. Research described in this thesis further investigated toluene biosynthesis by a microbial consortium originating from chlorinated solvent-contaminated groundwater near Baton Rouge, Louisiana. In anoxic growth media supplemented with phenylacetate as a precursor, toluene accumulation was found to be maximal at near-neutral to slightly acidic pHs (toluene accumulation greater than 1 mg/L at pH in the range of 5.6 to 7.6, but was not observed for …

Engineering The Lanthanide And Actinide Dopants Effects On The Local Environment Of Luminescent Complex Metal Oxide, Yuming Wang

LSU Doctoral Dissertations

Rare earth (RE) based phosphor materials are widely used as luminescent probes in high-temperature optical thermometry where standard methods are unsuitable. The current generation of luminescent thermometers lacks stability and energy transport within the operating temperature ranges. The challenge is developing an oxide-based material with high luminescence intensity and thermal sensitivity/stability, suitable for an optical temperature sensor/thermal barrier coating. This work aims to develop a fundamental understanding of the local environment surrounding RE or actinide dopants in metal oxide hosts to engineer their luminescence property. To maximize the luminescence, the local symmetry, doping concentration, and radiative/non-radiative relaxation pathways must be …

Effects Of Hypoxia And High Temperature On Eastern Oysters: Investigating Differential Tolerance In Populations And Ploidies, Nicholas C. Coxe

LSU Master's Theses

Increasing prevalence of hypoxia in estuarine waters can pose a serious threat to eastern oysters (Crassostrea virginica). While oysters are considered more tolerant to hypoxia than many other bivalves, their tolerance at temperatures of 28 °C and above, typical in northern Gulf of Mexico estuaries in the summer, is not well characterized. Moreover, it is unknown whether differences in hypoxia tolerance exist among oyster populations or between diploid and triploid oysters. To investigate population differences, wild oysters were collected from four estuaries in the northern and northwestern Gulf of Mexico and spawned. In a series of studies, the …

Optimizing The Performance Of Parallel And Concurrent Applications Based On Asynchronous Many-Task Runtimes, Weile Wei

LSU Doctoral Dissertations

Nowadays, High-performance Computing (HPC) scientific applications often face per- formance challenges when running on heterogeneous supercomputers, so do scalability, portability, and efficiency issues. For years, supercomputer architectures have been rapidly changing and becoming more complex, and this challenge will become even more com- plicated as we enter the exascale era, where computers will exceed one quintillion cal- culations per second. Software adaption and optimization are needed to address these challenges. Asynchronous many-task (AMT) systems show promise against the exascale challenge as they combine advantages of multi-core architectures with light-weight threads, asynchronous executions, smart scheduling, and portability across diverse architectures.

In …

Integration Of Solar + Storage Installation Upstream In Modular Construction, Ondrej Labik

LSU Master's Theses

High initial costs, mainly due to inefficient construction processes, remains the greatest barrier for residential adoption of solar+storage (SPS) system. Modular construction, having a factory-controlled environment and control over the home design, is well suited to address these issues (e.g., efficiencies, waste, inventory control, quality). Furthermore, these areas have great potential in modular construction to address the high initial cost issue. This study focuses on the integration of SPS installation upstream in modular housing. Although moving the SPS installation process into the factory has many barriers (e.g., including change of scope of work at some workstations without affecting the whole …

Hybrid Modulated-Phase-Grating For Phase Contrast X-Ray For A Varying Fringe Period Clinical Interferometry System, Elizabeth Jeong Park

LSU Master's Theses

Phase contrast x-rays are of use due to the range of imaging they can provide. Not only are they useful for attenuation they also can provide phase and small angle scatter X-ray (SAXS) information simultaneously which adds additional contrast and information to the original attention image. In prior work, a phase contrast system with Modulated Phase Grating was shown to eliminate the need for analyzer in standard Talbot Lau Xray Interferometers (TLXI). The system is clinically compatible in footprint due to its length being limited to

Accident Simulation Study For Nuclear Power Plants Impacting Louisiana, Michael D. Mcmahon

LSU Master's Theses

INTRODUCTION: Louisiana has aligned its radiological emergency program with the 2017 Environmental Protection Agency Protective Action Guides Manual, but has added a child thyroid dose evacuation threshold in lieu of distributing Potassium Iodide to the public. The nuclear power plants will continue to align with the 1992 manual for the foreseeable future, so that under some accident scenarios the state recommendations will differ from those of the utility.

OBJECTIVE: The objective of this study is to predict what accident and weather conditions will lead to a differing set of recommendations.

METHODS: More than 1000 simulations were performed of low-filtration nuclear …

Bloch Spectra For High Contrast Elastic Media, Jayasinghage Ruchira Nirmali Perera

LSU Doctoral Dissertations

The primary goal of this dissertation is to develop analytic representation formulas and power series to describe the band structure inside periodic elastic crystals made from high contrast inclusions. We use source free modes associated with structural spectra to represent the solution operator of the Lame' system inside phononic crystals. Then we obtain convergent power series for the Bloch wave spectrum using the representation formulas. An explicit bound on the convergence radius is given through the structural spectra of the inclusion array and the Dirichlet spectra of the inclusions. Sufficient conditions for the separation of spectral branches of the dispersion …

Self-Healing Composite Of Thermoset Polymer And Programmed Super Contraction Fibers, Guoqiang Li, Harper Meng

College of Engineering Patents

A composition comprising thermoset polymer, shape memory polymer to facilitate macro scale damage closure, and methods for molecular scale healing are provided. The composition can resolve structural defects by a bio-mimetic close-then heal process. In use, the shape memory polymer can provide molecular scale healing in a structural defect. The methods for molecular scale healing can include heating a composition including a thermoplastic such as fibers, particles or spheres to a level at or above the thermoplastic's melting point, then cooling of the composition below the melting temperature of the thermoplastic. The compositions have the ability to close macroscopic defects …

Self-Repelling Elastic Manifolds With Low Dimensional Range, Carl Mueller, Eyal Neumann

Journal of Stochastic Analysis

No abstract provided.

Induced Matrices: Recurrences And Markov Chains, Philip Feinsilver

Journal of Stochastic Analysis

No abstract provided.

From Equal-Mass To Extreme-Mass-Ratio Binary Inspirals: Simulation Tools For Next Generation Gravitational Wave Detectors, Samuel Douglas Cupp

LSU Doctoral Dissertations

Current numerical codes can successfully evolve similar-mass binary black holes systems, and these numerical waveforms contributed to the success of the LIGO Collaboration's detection of gravitational waves. LIGO requires high resolution numerical waveforms for detection and parameter estimation of the source. Great effort was expended over several decades to produce the numerical methods used today. However, future detectors will require further improvements to numerical techniques to take full advantage of their detection capabilities. For example, the Laser Interferometer Space Antenna (LISA) will require higher resolution simulations of similar-mass-ratio systems than LIGO. LISA will also be able to detect extreme-mass-ratio inspiral …

A Century-Long Trajectory Of Phosphorus Loading And Export From Mississippi River Basin To The Gulf Of Mexico: Contributions Of Multiple Environmental Changes, Zihao Bian, Shufen Pan, Zhuonan Wang, Yuanzhi Yao, Rongting Xu, Hao Shi, Latif Kalin, Christopher Anderson, Dubravko Justic, Steven Lohrenz, Hanqin Tian

Faculty Publications

Phosphorus (P) control is critical to mitigating eutrophication in aquatic ecosystems, but the effectiveness of controlling P export from soils has been limited by our poor understanding of P dynamics along the land-ocean aquatic continuum as well as the lack of well-developed process models that effectively couple terrestrial and aquatic biogeochemical P processes. Here, we coupled riverine P biogeochemical processes and water transport with terrestrial processes within the framework of the Dynamic Land Ecosystem Model to assess how multiple environmental changes, including fertilizer and manure P uses, land use, climate, and atmospheric CO2, have affected the long-term dynamics of P …

Phylogenetic Characterization And Genome Sequence Analysis Of Burkholderia Glumae Strains Isolated In Thailand As The Causal Agent Of Rice Bacterial Panicle Blight, Nootjarin Jungkhun, Antonio Roberto Gomes De Farias, Jutatape Watcharachaiyakup, Nuttima Kositcharoenkul, Jong Hyun Ham, Sujin Patarapuwadol

Faculty Publications

Burkholderia glumae is one of the most critical rice-pathogenic bacteria, and it causes bacterial panicle blight (BPB) in rice plants. In 2017, BPB symptoms were observed from rice fields in Chiang Rai, Northern Thailand. Sixty-one isolates obtained from the symptomatic panicles of rice were initially identified as B. glumae by polymerase chain reaction (PCR) using species-specific primers. Among them, six selected strains isolated from the susceptible japonica rice cultivar DOA2 were characterized in terms of morpho-physiology, pathology, phylogenetics, and genomics. Our genome sequence analysis of the six selected strains revealed the presence of multiple prophages, which may reflect the high …

Loss Of Function Of Renal Glut2 Reverses Hyperglycaemia And Normalises Body Weight In Mouse Models Of Diabetes And Obesity, Leticia Maria De Souza Cordeiro, Lauren Bainbridge, Nagavardhini Devisetty, David H. Mcdougal, Dorien J.M. Peters, Kavaljit H. Chhabra

Division of Basic Science Faculty Publications

Aims/hypothesis: Renal GLUT2 is increased in diabetes, thereby enhancing glucose reabsorption and worsening hyperglycaemia. Here, we determined whether loss of Glut2 (also known as Slc2a2) specifically in the kidneys would reverse hyperglycaemia and normalise body weight in mouse models of diabetes and obesity. Methods: We used the tamoxifen-inducible CreERT2-Lox system in mice to knockout Glut2 specifically in the kidneys (Ks-Glut2 KO) to establish the contribution of renal GLUT2 to systemic glucose homeostasis in health and in insulin-dependent as well as non-insulin-dependent diabetes. We measured circulating glucose and insulin levels in response to OGTT or IVGTT under different experimental conditions in …

Assessing The Initial Validity Of The Portionsize App To Estimate Dietary Intake Among Adults: Pilot And Feasibility App Validation Study, Sanjoy Saha, Chloe Panizza Lozano, Stephanie Broyles, Corby K. Martin, John W. Apolzan

Clinical Research Faculty Publications

Background: Accurately assessing dietary intake can promote improved nutrition. The PortionSize app (Pennington Biomedical Research Center) was designed to quantify and provide real-time feedback on the intake of energy, food groups, saturated fat, and added sugar. Objective: This study aimed to assess the preliminary feasibility and validity of estimating food intake via the PortionSize app among adults. Methods: A total of 15 adults (aged 18-65 years) were recruited and trained to quantify the food intake from a simulated meal by using PortionSize. Trained personnel prepared 15 simulated meals and covertly weighed (weigh back) the amount of food provided to participants …

Interindividual Variation In Maximum Aerobic Metabolism Varies With Gill Morphology And Myocardial Bioenergetics In Gulf Killifish, Bernard B. Rees, Jessica E. Reemeyer, Brian A. Irving

Faculty Publications

This study asked whether interindividual variation in maximum and standard aerobic metabolic rates of the Gulf killifish, Fundulus grandis, correlates with gill morphology and cardiac mitochondrial bioenergetics, traits reflecting critical steps in the O2 transport cascade from the environment to the tissues. Maximum metabolic rate (MMR) was positively related to body mass, total gill filament length and myocardial oxygen consumption during maximum oxidative phosphorylation (multiple R2=0.836). Standard metabolic rate (SMR) was positively related to body mass, total gill filament length and myocardial oxygen consumption during maximum electron transport system activity (multiple R2=0.717). After controlling for body mass, individuals with longer …

Comprehensive Analysis Of Epigenetic Clocks Reveals Associations Between Disproportionate Biological Ageing And Hippocampal Volume, Lidija Milicic, Michael Vacher, Tenielle Porter, Vincent Doré, Samantha C. Burnham, Pierrick Bourgeat, Rosita Shishegar, James Doecke, Nicola J. Armstrong, Rick Tankard, Paul Maruff, Colin L. Masters, Christopher C. Rowe, Victor L. Villemagne, Simon M. Laws, Balebail Ashok Raj, Kristin Fargher, Amanda Smith, Lisa Raudin, Gloria Chaing, Norman Relkin, Karen Elizabeth Smith, Hyungsub Shim, Laura L. Boles Ponto, Susan K. Schultz, Antero Sarrael, Raymundo Hernando, Nunzio Pomara, Dick Drost, Andrew Kertesz, John Rogers, Irina Rachinsky, Stephen Pasternak, Elizabether Finger

Clinical Research Faculty Publications

The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised measures of age acceleration, based on DNA methylation patterns (DNAm age), and cross-sectional and longitudinal cognition and AD-related neuroimaging phenotypes (volumetric MRI and Amyloid-β PET) in the Australian Imaging, Biomarkers and Lifestyle (AIBL) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Significant …

Novel Approaches To Environmental Monitoring And Control Of Listeria Monocytogenes In Food Production Facilities, Priyanka Gupta, Achyut Adhikari

Faculty Publications

Listeria monocytogenes is a serious public health hazard responsible for the foodborne illness listeriosis. L. monocytogenes is ubiquitous in nature and can become established in food production facilities, resulting in the contamination of a variety of food products, especially ready-to-eat foods. Effective and risk-based environmental monitoring programs and control strategies are essential to eliminate L. monocytogenes in food production environments. Key elements of the environmental monitoring program include (i) identifying the sources and prevalence of L. monocytogenes in the production environment, (ii) verifying the effectiveness of control measures to eliminate L. monocytogenes, and (iii) identifying the areas and activities to …

Passive Laser Power Stabilization Via An Optical Spring, Torrey Cullen, Scott Aronson, Ron Pagano, Marina Trad Nery, Henry Cain, Jonathon Cripe, Garrett D. Cole, Safura Sharifi, Nancy Aggarwal, Benno Willke, Thomas Corbitt

Faculty Publications

Metrology experiments can be limited by the noise produced by the laser involved via small fluctuations in the laser’s power or frequency. Typically, active power stabilization schemes consisting of an in-loop sensor and a feedback control loop are employed. Those schemes are fundamentally limited by shot noise coupling at the in-loop sensor. In this Letter, we propose to use the optical spring effect to passively stabilize the classical power fluctuations of a laser beam. In a proof of principle experiment, we show that the relative power noise of the laser is stabilized from approximately 2 × 10⁻⁵ Hz^{−1 …}

Thinking Outside The Box: Numerical Relativity With Particles, Stephan Rosswog, Peter Diener, Francesco Torsello

Faculty Publications

The observation of gravitational waves from compact objects has now become an active part of observational astronomy. For a sound interpretation, one needs to compare such observations against detailed Numerical Relativity simulations, which are essential tools to explore the dynamics and physics of compact binary mergers. To date, essentially all simulation codes that solve the full set of Einstein’s equations are performed in the framework of Eulerian hydrodynamics. The exception is our recently developed Numerical Relativity code SPHINCS_BSSN which solves the commonly used BSSN formulation of the Einstein equations on a structured mesh and the matter equations via Lagrangian particles. …

The Lsu Campus Mounds, With Construction Beginning At ~11,000 Bp, Are The Oldest Known Extant Man-Made Structures In The Americas, Brooks B. Ellwood, Sophie Warny, Rebecca A. Hackworth, Suzanne H. Ellwood, Jonathan H. Tomkin, Samuel J. Bentley, Dewitt H. Braud, Geoffrey C. Clayton

Faculty Publications

Radiocarbon dating of the two LSU Campus Mounds (16EBR6) indicates that the construction of one, Mound B, began at ~11,000 BP, making Mound B the oldest known and intact manmade structure in the Americas. The age analyses preesented here are based on thirty one 14C dates. The older (deeper) parts of both of the LSU Campus Mounds contain many thin, burned ash lenses, suggesting that the Mounds may have been used for ceremonial or cremation purposes. These ash layers are composed mainly of phytoliths, bio-silicate (SiO2) structural compounds in plants that remained after burning of these plants. Analysis of the …

Comparison Of Microstructure And Tensile Behavior Of Hydroxyapatite-Coated Peek Meshes And Cellulose-Based Fabrics And Mats, Armaghan Naderi, Genevieve Palardy

Faculty Publications

Polymeric biomaterials, such as polyether ether ketone (PEEK) and cellulose, have been explored as scaffolds for bone tissue engineering in the past decade. In this study, microstructure and mechanical behavior of uncoated and hydroxyapatite (HA)-coated polymeric meshes, fabrics, and mats were investigated. Commercially available monofilament PEEK meshes, and cellulose fabrics and mats were selected, then coated with a customized low temperature sol–gel method (≤ 150°C). Adhesive HA coating consisting of HA, β-TCP, and CaO with nanorod structure was derived. After HA coating, porosity of substrates (except filter-paper cellulose mats) decreased by up to 43%, indicating effective coating. Both uncoated and …

Nature Versus Humans In Coastal Environmental Change: Assessing The Impacts Of Hurricanes Zeta And Ida In The Context Of Beach Nourishment Projects In The Mississippi River Delta, Qiang Yao, Marcelo Cancela Lisboa Cohen, Kam-Biu Liu, Adriana Vivan De Souza, Erika Rodrigues

Faculty Publications

No abstract provided.

Dynamics Of Polymer Melts And Polymer Nanocomposites Studied By Broadband Dielectric Spectroscopy, Mengchun Wu

LSU Doctoral Dissertations

Materials based on polymers and polymeric nanocomposites have properties advantageous for many applications. In many cases, the physical behavior is connected to molecular motion. Polymers are macromolecules in which both fast local motions and slower chain relaxations may contribute to the material properties. Answering fundamental questions on the molecular dynamics is challenging, because of the existence of many different processes and the strong temperature dependence of the processes. An investigation covering a broad window over many orders of magnitude in the time scale is needed. Hence, dielectric spectroscopy is an appropriate tool to enhance fundamental understanding. This dissertation pays special …