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Entropic Signatures Of The Skyrmion Lattice Phase In Mnsi1-Xalx And Fe1-Ycoysi, C. Dhital, J. F. Ditusa

Faculty Publications

The entropic signatures of magnetic phase transitions in the skyrmion lattice host compounds MnSi0.962Al0.038 and Fe0.7Co0.3Si were investigated through low field magnetization and ac susceptibility measurements. These data indicate that the conical to skyrmion transition that occurs with the application of magnetic field in MnSi0.962Al0.038 is characterized by clear discontinuity in the magnetic entropy as expected for first order topological phase transition. These same magnetoentropic features are negligibly small in isostructural Fe0.7Co0.3Si due to the level of chemical substitution related disorder and differences in the spin dynamics (range and timescales). Despite the obvious similarities in the magnetic structures of these …

Reinforcement Learning Approach For Inspect/Correct Tasks, Hoda Nasereddin

LSU Doctoral Dissertations

In this research, we focus on the application of reinforcement learning (RL) in automated agent tasks involving considerable target variability (i.e., characterized by stochastic distributions); in particular, learning of inspect/correct tasks. Examples include automated identification & correction of rivet failures in airplane maintenance procedures, and automated cleaning of surgical instruments in a hospital sterilization processing department. The location of defects and the corrective action to be taken for each varies from task episode. What needs to be learned are optimal stochastic strategies rather than optimization of any one single defect type and location. RL has been widely applied in robotics …

An Improved Foam Modeling Technique And Its Application To Petroleum Drilling And Production Practice, Yanfang Wang

LSU Doctoral Dissertations

Foam is one of the most common used multiphase fluid in Underbalanced Drilling (UBD) and Managed Pressure Drilling (MPD). Because of its low density, high capacity of lifting and carrying cuttings, low cost and compatibility with formations, foam has become more superior than the conventional drilling mud when depleted reservoir pressure, severe lost circulation, or unstable borehole are encountered. In general, the success of foam applications rely on the understanding of the fundamentals of foam rheology in downhole conditions.

Foam rheology has been studied for decades. Conventional foam rheological models such as Power Law, Bingham Plastic, Herschel-Bulkley to explain foam …

R(P,Q) Analogs Of Discrete Distributions: General Formalism And Applications, Mahouton Norbert Hounkonnou, Fridolin Melong

Journal of Stochastic Analysis

No abstract provided.

The Yang-Mills Heat Equation On Three-Manifolds With Boundary, Nelia Charalambous

Journal of Stochastic Analysis

No abstract provided.

Machine Learning Based Applications For Data Visualization, Modeling, Control, And Optimization For Chemical And Biological Systems, Yan Ma

LSU Doctoral Dissertations

This dissertation report covers Yan Ma’s Ph.D. research with applicational studies of machine learning in manufacturing and biological systems. The research work mainly focuses on reaction modeling, optimization, and control using a deep learning-based approaches, and the work mainly concentrates on deep reinforcement learning (DRL). Yan Ma’s research also involves with data mining with bioinformatics. Large-scale data obtained in RNA-seq is analyzed using non-linear dimensionality reduction with Principal Component Analysis (PCA), t-Distributed Stochastic Neighbor Embedding (t-SNE), and Uniform Manifold Approximation and Projection (UMAP), followed by clustering analysis using k-Means and Hierarchical Density-Based Spatial Clustering with Noise (HDBSCAN). This report focuses …

Emergence Of Quantum Theories From Classical Probability: Historical Origins, Developments, And Open Problems, Luigi Accardi, Yun-Gang Lu

Journal of Stochastic Analysis

No abstract provided.

Mixed Messages: Reading Contemporary U.S. Literature Of Biracial Girlhood, Candice Nicole Hale

LSU Doctoral Dissertations

The tragic mulatta character is no longer an accurate representation of biracial female characters in literature. This dissertation considers the vast history of the tragic mulatto genre and its tragic and mired representations of biracial women and how they are often portrayed in literature. Within a historical, legal, and political analysis, I highlight the ways perceptions, attitudes, and representations about biracial individuals have changed, so those same shifts should change in the literature. Because of the bourgeoning field of Critical Mixed Race Studies (CMRS), both scholars and authors are recasting and rewriting the narratives and discourses of mixed-race in the …

Comparing Multiple Comparisons: Practical Guidance For Choosing The Best Multiple Comparisons Test, Stephen Midway, Matthew Robertson, Shane Flinn, Michael Kaller

Faculty Publications

Multiple comparisons tests (MCTs) include the statistical tests used to compare groups (treatments) often following a significant effect reported in one of many types of linear models. Due to a variety of data and statistical considerations, several dozen MCTs have been developed over the decades, with tests ranging from very similar to each other to very different from each other. Many scientific disciplines use MCTs, including >40,000 reports of their use in ecological journals in the last 60 years. Despite the ubiquity and utility of MCTs, several issues remain in terms of their correct use and reporting. In this study, …

Publisher Correction: Exuberant Fibroblast Activity Compromises Lung Function Via Adamts4 (Nature, (2020), 587, 7834, (466-471), 10.1038/S41586-020-2877-5), David F. Boyd, E. Kaitlynn Allen, Adrienne G. Randolph, Xi Zhi J. Guo, Yunceng Weng, Catherine J. Sanders, Resha Bajracharya, Natalie K. Lee, Clifford S. Guy, Peter Vogel, Wenda Guan, Yimin Li, Xiaoqing Liu, Tanya Novak, Margaret M. Newhams, Thomas P. Fabrizio, Nicholas Wohlgemuth, Peter M. Mourani, Michele Kong, Ronald C. Sanders, Katherine Irby, Katri Typpo, Barry Markovitz, Natalie Cvijanovich, Heidi Flori, Adam Schwarz, Nick Anas, Peter Mourani, Angela Czaja, Gwenn Mclaughlin, Matthew Paden, Keiko Tarquinio, Bria M. Coates, Neethi Pinto

Faculty Publications

© 2020, The Author(s), under exclusive licence to Springer Nature Limited. An amendment to this paper has been published and can be accessed via a link at the top of the paper.

An Asymptotic Formula For Integrals Of Products Of Jacobi Polynomials, Maxim Derevyagin, Nicholas Juricic

Journal of Stochastic Analysis

No abstract provided.

Groundwater Production From Geothermal Heating On Early Mars And Implication For Early Martian Habitability, Lujendra Ojha, Jacob Buffo, Suniti Karunatillake, Matthew Siegler

Faculty Publications

Copyright © 2020 The Authors, In explaining extensive evidence for past liquid water, the debate on whether Mars was primarily warm and wet or cold and arid 4 billion years (Ga) ago has continued for decades. The Sun’s luminosity was ~30% lower 4 Ga ago; thus, most martian climate models struggle to elevate the mean surface temperature past the melting point of water. Basal melting of ice sheets may help resolve that paradox. We modeled the thermophysical evolution of ice and estimate the geothermal heat flux required to produce meltwater on a cold, arid Mars. We then analyzed geophysical and …

Yap/Taz Deficiency Reprograms Macrophage Phenotype And Improves Infarct Healing And Cardiac Function After Myocardial Infarction, Masum M. Mia, Dasan Mary Cibi, Siti Aishah Binte Abdul Ghani, Weihua Song, Nicole Tee, Sujoy Ghosh, Junhao Mao, Eric N. Olson, Manvendra K. Singh

Division of Basic Science Faculty Publications

Adverse cardiac remodeling after myocardial infarction (MI) causes structural and functional changes in the heart leading to heart failure. The initial post-MI pro-inflammatory response followed by reparative or anti-inflammatory response is essential for minimizing the myocardial damage, healing, and scar formation. Bone marrow-derived macrophages (BMDMs) are recruited to the injured myocardium and are essential for cardiac repair as they can adopt both pro-inflammatory or reparative phenotypes to modulate inflammatory and reparative responses, respectively. Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are the key mediators of the Hippo signaling pathway and are essential for cardiac regeneration and repair. …

Universal Molecular Processor For Precision Medicine, Steven A. Soper, Francis Barany, Sunggook Park, Michael Murphy, Collin J. Mckinney, John William Efcavitch, Mateusz L. Hupert

College of Science Patents

No abstract provided.

Rare Earth Element Distributions In Continental Shelf Sediment, Northern South China Sea, Qian Ge, Z. George Xue, Fengyou Chu

Faculty Publications

A total of 388 surface sediment samples taken from the northern South China Sea (SCS) continental shelf were analyzed to characterize the signature of their rare earth elements (REEs). The average REEs concentration was 192.94 µg/g, with a maximum of 349.07 µg/g, and a minimum of 32.97 µg/g. The chondrite-normalized REEs pattern exhibits a remarkably light REEs accumulation, a relatively flat heavy REEs pattern, and a negative Eu anomaly. We subdivided the study area into three zones using the characteristics of REEs and statistical characteristics. Zone I: continental shelf off western Guangdong Province. Here, the sediment provenance is mainly river-derived …

Principles Of Effective Data Visualization, Stephen R. Midway

Faculty Publications

No abstract provided.

Contrasting Hydrodynamic Responses To Atmospheric Systems With Different Scales: Impact Of Cold Fronts Vs. That Of A Hurricane, Wei Huang, Chunyan Li

Faculty Publications

In this paper, subtidal responses of Barataria Bay to an atmospheric cold front in 2014 and Hurricane Barry of 2019 are studied. The cold fronts had shorter influencing periods (1 to 3 days), while Hurricane Barry had a much longer influencing period (about 1 week). Wind direction usually changes from southern quadrants to northern quadrants before and after a cold front’s passage. For a hurricane making its landfall at the norther Gulf of Mexico coast, wind variation is dependent on the location relative to the location of landfall. Consequently, water level usually reaches a trough after the maximum cold front …

Waves On Louisiana Continental Shelf Influenced By Atmospheric Fronts, Biyun Guo, M. V. Subrahmanyam, C. Li

Faculty Publications

Ocean-atmospheric dynamical processes influence the wave characteristics, and sea surface temperature (SST). The processes that affect SST in the ocean area included surface heat fluxes, wind, and precipitation. In this study, we analyzed the wave data in response to the cold front passages over Louisiana continental shelf. The data examined in this research is mainly from WAVCIS (Wave-Current-surge Information System), Coastal Ocean Estuarine Dynamics Lab at Louisiana State University and Global Precipitation Climatology Project (GPCP). With respect to the wave response to the atmospheric forcing, here we consider: (1) the connection between wave variability and atmospheric frontal passages, and (2) …

Nationwide Hvac Energy-Saving Potential Quantification For Office Buildings With Occupant-Centric Controls In Various Climates, Zhihong Pang, Yan Chen, Jian Zhang, Zheng O'Neill, Hwakong Cheng, Bing Dong

Faculty Publications

The occupant-centric control (OCC) is receiving an increasing attention since it could reduce building heating ventilation and air-conditioning (HVAC) system energy consumptions while not affecting the occupant thermal comfort. This paper aims to quantify the nationwide energy-saving potential of implementing the occupant-centric HVAC controls in typical office buildings. First, the medium office and large office from the Department of Energy (DOE) Commercial Prototype Building Models (CPBM) were enhanced to have detailed layouts and dynamic occupancy schedules. Then, a comprehensive simulation plan was created by incorporating the multiple zone-level and system-level occupant-centric building HVAC controls recommended by the updated ASHRAE Standard …

Geographic Patterns And Environmental Correlates Of Phylogenetic Relatedness And Diversity For Freshwater Fish Assemblages In North America, Hong Qian, Yong Cao, Daijiang Li, Cindy Chu, Brody Sandel, Xianli Wang

Faculty Publications

© 2020 The Authors. Ecography published by John Wiley & Sons Ltd on behalf of Nordic Society Oikos The tropical niche conservatism hypothesis suggests that most groups should be most phylogenetically clustered in cold, dry environments. This idea has been well-tested in plants and some animal groups, but not for fishes. We assess the geographic patterns of freshwater fish phylogenetic structure and investigate the relationships between these patterns and environmental variables across North America and within two biogeographic realms. Phylogenetic relatedness and diversity of 360 freshwater fish assemblages across North America were quantified with three metrics based on a well-dated …

Fenugreek Counters The Effects Of High Fat Diet On Gut Microbiota In Mice: Links To Metabolic Benefit, Annadora J. Bruce-Keller, Allison J. Richard, Sun Ok Fernandez-Kim, David M. Ribnicky, J. Michael Salbaum, Susan Newman, Richard Carmouche, Jacqueline M. Stephens

Faculty Publications

© 2020, The Author(s). Fenugreek (Trigonella foenum-graecum) is an annual herbaceous plant and a staple of traditional health remedies for metabolic conditions including high cholesterol and diabetes. While the mechanisms of the beneficial actions of fenugreek remain unknown, a role for intestinal microbiota in metabolic homeostasis is likely. To determine if fenugreek utilizes intestinal bacteria to offset the adverse effects of high fat diets, C57BL/6J mice were fed control/low fat (CD) or high fat (HFD) diets each supplemented with or without 2% (w/w) fenugreek for 16 weeks. The effects of fenugreek and HFD on gut microbiota were comprehensively mapped and …

Reconstructing Genomes Of Carbon Monoxide Oxidisers In Volcanic Deposits Including Members Of The Class Ktedonobacteria, Marcela Hernández, Blanca Vera-Gargallo, Marcela Calabi-Floody, Gary M. King, Ralf Conrad, Christoph C. Tebbe

Faculty Publications

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Microorganisms can potentially colonise volcanic rocks using the chemical energy in reduced gases such as methane, hydrogen (H2) and carbon monoxide (CO). In this study, we analysed soil metagenomes from Chilean volcanic soils, representing three different successional stages with ages of 380, 269 and 63 years, respectively. A total of 19 metagenome-assembled genomes (MAGs) were retrieved from all stages with a higher number observed in the youngest soil (1640: 2 MAGs, 1751: 1 MAG, 1957: 16 MAGs). Genomic similarity indices showed that several MAGs had amino-acid identity (AAI) values >50% to …

Strengthening Spatial Reasoning: Elucidating The Attentional And Neural Mechanisms Associated With Mental Rotation Skill Development, Katherine C. Moen, Melissa R. Beck, Stephanie M. Saltzmann, Tovah M. Cowan, Lauryn M. Burleigh, Leslie G. Butler, Jagannathan Ramanujam, Alex S. Cohen, Steven G. Greening

Faculty Publications

© 2020, The Author(s). Spatial reasoning is a critical skill in many everyday tasks and in science, technology, engineering, and mathematics disciplines. The current study examined how training on mental rotation (a spatial reasoning task) impacts the completeness of an encoded representation and the ability to rotate the representation. We used a multisession, multimethod design with an active control group to determine how mental rotation ability impacts performance for a trained stimulus category and an untrained stimulus category. Participants in the experimental group (n = 18) showed greater improvement than the active control group (n = 18) on the mental …

Impact Of Local Stiffness On Entropy Driven Microscopic Dynamics Of Polythiophene, Sudipta Gupta, Sourav Chatterjee, Piotr Zolnierczuk, Evgueni E. Nesterov, Gerald J. Schneider

Faculty Publications

© 2020, The Author(s). We exploited the high temporal and spatial resolution of neutron spin echo spectroscopy to investigate the large-scale dynamics of semiflexible conjugated polymer chains in solutions. We used a generalized approach of the well-established Zimm model of flexible polymers to describe the relaxation mode spectra of locally stiff polythiophene chains. The Zimm mode analysis confirms the existence of beads with a finite length that corresponds to a reduced number of segmental modes in semiflexible chains. Irrespective of the temperature and the molecular weight of the conjugated polymer, we witness a universal behavior of the local chain stiffness …

Calorie Restriction For Enhanced Longevity: The Role Of Novel Dietary Strategies In The Present Obesogenic Environment, James L. Dorling, Corby K. Martin, Leanne M. Redman

Clinical Research Faculty Publications

Calorie restriction (CR) is a potent modulator of longevity in multiple species. A growing body of evidence shows that sustained periods of CR without malnutrition improves risk factors involved in the pathophysiology of type 2 diabetes, cardiovascular diseases, cancer, and neurological disorders in humans. Innovative dietary strategies such as intermittent fasting and protein restriction have recently emerged as alternative approaches that improve markers of aging. Some of these newer strategies might provide benefits for healthy aging with little to no CR and therefore, compared to traditional CR, may be easier to follow. Further to providing an update of CR studies …

Challenges And Opportunities With Causal Discovery Algorithms: Application To Alzheimer’S Pathophysiology, Xinpeng Shen, Sisi Ma, Prashanthi Vemuri, Gyorgy Simon, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, Andrew J. Saykin, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Adam Schwartz, Tom Montine, Ronald G. Thomas, Michael Donohue, Sarah Walter

Clinical Research Faculty Publications

Causal Structure Discovery (CSD) is the problem of identifying causal relationships from large quantities of data through computational methods. With the limited ability of traditional association-based computational methods to discover causal relationships, CSD methodologies are gaining popularity. The goal of the study was to systematically examine whether (i) CSD methods can discover the known causal relationships from observational clinical data and (ii) to offer guidance to accurately discover known causal relationships. We used Alzheimer’s disease (AD), a complex progressive disease, as a model because the well-established evidence provides a “gold-standard” causal graph for evaluation. We evaluated two CSD methods, Fast …

Comparison Of Conventional And Advanced Radiotherapy Techniques For Left-Sided Breast Cancer After Breast Conserving Surgery, Yibo Xie, Daniel Bourgeois, Beibei Guo, Rui Zhang

Faculty Publications

Whole breast radiotherapy (WBRT) after breast conserving surgery is the standard treatment to prevent recurrence and metastasis of early stage breast cancer. This study aims to compare seven WBRT techniques including conventional tangential, field-in-field (FIF), hybrid intensity-modulated radiotherapy (IMRT), IMRT, standard volumetric modulated arc therapy (STD-VMAT), noncoplanar VMAT (NC-VMAT), and multiple arc VMAT (MA-VMAT). Fifteen patients who were previously diagnosed with left-sided early stage breast cancer and treated in our clinic were selected for this study. WBRT plans were created for these patients and were evaluated based on target coverage and normal tissue toxicities. All techniques produced clinically acceptable WBRT …

Enhanced Hanbury Brown And Twiss Interferometry Using Parametric Amplification, Xiaoping Ma, Chenglong You, Sushovit Adhikari, Yongjian Gu, Omar S. Magaña-Loaiza, Jonathan P. Dowling, Hwang Lee

Faculty Publications

The Hanbury Brown and Twiss (HBT) interferometer was proposed to observe intensity correlations of starlight to measure a star’s angular diameter. As the intensity of light that reaches the detector from a star is very weak, one cannot usually get a workable signal-to-noise ratio. We propose an improved HBT interferometric scheme incorporating optical parametric amplifiers (OPA) into the system to amplify the correlation signal. Remarkably, for weak star light, the signal-to-noise ratio (SNR) in the new HBT interferometric scheme is much better than that of conventional HBT interferometer. Our work is valuable in measuring a star whose intensity at the …

Women Leaders And Policy Compliance During A Public Health Crisis, Nichole M. Bauer, Jeong Hyun Kim, Yesola Kweon

Faculty Publications

How does the gender of a political leader affect policy compliance of the public during a public health crisis? State and national leaders have taken a variety of policy measures to combat the COVID-19 pandemic, with varying levels of success. While many female leaders have been credited with containing the spread of COVID-19, often through implementing strict policy measures, there is little understanding of how individuals respond to public health policy recommendations made by female and male leaders. This article investigates whether citizens are more willing to comply with strict policy recommendations about a public health issue when those recommendations …

Enhanced Hanbury Brown And Twiss Interferometry Using Parametric Amplification, Xiaoping Ma, Chenglong You, Sushovit Adhikari, Yongjian Gu, Omar S. Magaña-Loaiza, Jonathan P. Dowling, Hwang Lee

Faculty Publications

The Hanbury Brown and Twiss (HBT) interferometer was proposed to observe intensity correlations of starlight to measure a star’s angular diameter. As the intensity of light that reaches the detector from a star is very weak, one cannot usually get a workable signal-to-noise ratio. We propose an improved HBT interferometric scheme incorporating optical parametric amplifiers (OPA) into the system to amplify the correlation signal. Remarkably, for weak star light, the signal-to-noise ratio (SNR) in the new HBT interferometric scheme is much better than that of conventional HBT interferometer. Our work is valuable in measuring a star whose intensity at the …