Digital Commons Network^™

Model Comparison From Ligo-Virgo Data On Gw170817'S Binary Components And Consequences For The Merger Remnant, B. P. Abbott, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, C. Adams, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, M. A. Aloy, P. A. Altin, A. Amato, S. Anand, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda, M. Arène, N. Arnaud

Faculty Publications

GW170817 is the very first observation of gravitational waves originating from the coalescence of two compact objects in the mass range of neutron stars, accompanied by electromagnetic counterparts, and offers an opportunity to directly probe the internal structure of neutron stars. We perform Bayesian model selection on a wide range of theoretical predictions for the neutron star equation of state. For the binary neutron star hypothesis, we find that we cannot rule out the majority of theoretical models considered. In addition, the gravitational-wave data alone does not rule out the possibility that one or both objects were low-mass black holes. …

Vibrational And Electronic Structure Of Environmentally Persistent Free Radicals Formed On Metal Oxide Nanoclusters And Single-Crystal Surfaces, Nadra Ibrahim Sakr

LSU Doctoral Dissertations

We have studied the morphology and electronic structure of transition metal oxides (TMOs) nanoparticles and single-crystal surfaces which are known to be active for the formation of environmentally persistent free radicals (EPFRs) from organic precursors. We have also investigated the effect of simulated solar irradiation on the formed EPFRs.

First, we examined the change in the vibrational and structural properties of TiO₂, ZnO, CuO, and Fe₂O₃ nanoparticles due to phenol adsorption at high temperature and thus EPFR formation on the surface of these TMOs. The paramagnetic signal observed by electron paramagnetic resonance (EPR) indicates the …

Influence Of Neighboring Clonal-Colonies On Aflatoxin Production By Aspergillus Flavus, Rebecca R. Sweany, Kenneth E. Damann

Faculty Publications

Aspergillus flavus is an ascomycete fungus that infects and contaminates corn, peanuts, cottonseed, and treenuts with acutely toxic and carcinogenic aflatoxins. The ecological function of aflatoxin production is not well understood; though not phytotoxic, aflatoxin may be involved in resisting oxidative stress responses from infection or drought stress in plants. Observation of aflatoxin stimulation in 48-well plates in response to increasing inoculated wells sparked an investigation to determine if A. flavus volatiles influence aflatoxin production in neighboring colonies. Experiments controlling several culture conditions demonstrated a stimulation of aflatoxin production with increased well occupancy independent of pH buffer, moisture, or isolate. …

A Robust Solver For A Second Order Mixed Finite Element Method For The Cahn–Hilliard Equation, Susanne C. Brenner, Amanda E. Diegel, Li Yeng Sung

Faculty Publications

We develop a robust solver for a second order mixed finite element splitting scheme for the Cahn–Hilliard equation. This work is an extension of our previous work in which we developed a robust solver for a first order mixed finite element splitting scheme for the Cahn–Hilliard equation. The key ingredient of the solver is a preconditioned minimal residual algorithm (with a multigrid preconditioner) whose performance is independent of the spatial mesh size and the time step size for a given interfacial width parameter. The dependence on the interfacial width parameter is also mild.

Spatial And Topological Analysis Of Urban Land Cover Structure In New Orleans Using Multispectral Aerial Image And Lidar Data, Shuxian Liu

LSU Master's Theses

Urban land use and land cover (LULC) mapping has been one of the major applications in remote sensing of the urban environment. Land cover refers to the biophysical materials at the surface of the earth (i.e. grass, trees, soils, concrete, water), while land use indicates the socio-economic function of the land (i.e., residential, industrial, commercial land uses). This study addresses the technical issue of how to computationally infer urban land use types based on the urban land cover structures from remote sensing data. In this research, a multispectral aerial image and high-resolution LiDAR topographic data have been integrated to investigate …

Synergetic Effect On Catalytic Activity And Charge Transfer In Pt-Pd Bimetallic Model Catalysts Prepared By Atomic Layer Deposition, Moon Hyung Jang, Orhan Kizilkaya, A. Jeremy Kropf, Richard L. Kurtz, Jeffrey W. Elam, Yu Lei

Faculty Publications

Pt-Pd bimetallic nanoparticles were synthesized on TiO2 support on the planar substrate as well as on high surface area SiO2 gel by atomic layer deposition to identify the catalytic performance improvement after the formation of Pt-Pd bimetallic nanoparticles by surface analysis techniques. From X-ray absorption near edge spectra of Pt-Pd bimetallic nanoparticles, d-orbital hybridization between Pt 5d and Pd 4d was observed, which is responsible for charge transfer from Pt to Pd. Moreover, it was found from the in situ grazing incidence X-ray absorption spectroscopy study that Pt-Pd nanoparticles have a Pd shell/Pt core structure with CO adsorption. Resonant photoemission …

Structural Analysis Of Ultrasoft Pdms- G-Pdms Shell-Only Particles, Karin J. Bichler, Bruno Jakobi, Stefan O. Huber, Elliot P. Gilbert, Gerald J. Schneider

Faculty Publications

Copyright © 2019 American Chemical Society. We have used anionic polymerization to synthesize polymers of linear and bottlebrush architecture each with a polydimethylsiloxane backbone. The blending of polymer architectures has the effect of changing material properties, e.g., the viscoelasticity, which are connected to the chain conformation. Thus, we explore the conformation of bottlebrush polymers in a linear host melt both as a function of the concentration and for various molecular weights of the linear host matrices. Our bottlebrush polymers are seen as shell-only particles with a negligible core size. We find a substantial influence of the molecular weight of the …

Interactions Among Amygdala Volume, Cortical Thickness, And Structural Connectivity In Youth: Relationship To Emotion Regulation, Peter James Castagna

LSU Doctoral Dissertations

Emotion regulation includes adaptive (e.g., reappraisal) and non-adaptive behaviors (e.g., avoidance) designed to alter ones’ affective responses. The central hypothesis is that emotional consciousness – being self-aware that you are currently in a particular emotional state – and emotion regulation share the same underlying brain mechanisms/networks. In addition, it is argued that the more appropriate dichotomy, in regard to non-adaptive and adaptive emotion regulation strategies, is dependent on whether they are unconscious or conscious (respectively), positing a two-system framework of emotion regulation. Evidence for the proposed framework draws and builds off of recent theories of higher-order emotional consciousness (LeDoux & …

General Purpose Molecular Processor For Precision Medicine, Steve A. Soper, Francis Bernie, Sanguk Park, Michael C. Murphy, Collin J. Mckinney, John William Evkavich, Matthaus Huppert

College of Science Patents

No abstract provided.

Communication - Electrocatalytic Coupling Of Methane At Platinum Oxide Electrodes In Superacids, Guangfang Li, Yuxin Fang, Christopher Arges, Craig Plaisance, John Flake

Faculty Publications

Electrochemical oxidation of methane in the absence of chemical oxidants offers the potential to directly synthesize high value hydrocarbons at low temperatures. Experimental results demonstrate methane oxidization at oxidized Pt electrodes in liquid superacid electrolytes. Ethane and ethylene are observed as products under chronoamperometric experiments at room temperature. Faradaic efficiencies for C2 products range from 5% to 25% at anodic potentials between 0.8 to 1.4 V vs RHE. A generalized Lewis-acid Pt2+ mechanism including methylidene coupling is proposed.

Stellar Nucleosynthesis: Direct Measurement Of The Neutron-Capture Cross Sections Of Stable Germanium Isotopes And Design Of A Next Generation Ion Trap For The Study Of Beta-Delayed Neutron Emission, Alexander Laminack

LSU Doctoral Dissertations

Knowledge of stellar nuclear reaction rates is critical to understanding the cosmic origins of the abundances of elements. In order to determine these reaction rates, accurate measurements of nuclear cross sections are needed. This thesis presents the results of an experiment to directly measure the neutron capture cross sections of 70-Ge, 72-Ge, 74-Ge, and 76-Ge. These measurements were performed at the Los Alamos Neutron Science CEnter (LANSCE) using the Detector for Advanced Neutron Capture Experiments (DANCE). This is the first direct measurement for many of these isotopes across the neutron energy spectrum of 10 eV to 1 MeV using the …

A Study Of Particle-Laden Flows From Meso And Micro-Scale Perspectives, Daniel Guedes De Oliveira

LSU Doctoral Dissertations

Particle-laden flows are investigated numerically from a meso-scale perspective using Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) and from a micro-scale perspective using Particle Resolved Direct Numerical Simulation (PR-DNS). For the former, the dynamics of a pseudo-2D pulsed fluidized bed (PFB) consisting of 400,000 to 800,000 particles was investigated (Chapters 2 and 3). The focus is on the capabilities of CFD-DEM to (1) reproduce pattern formation in these systems and (2) further the understanding of the dynamics of PFB's as a function of pulsation parameters. In Chapter 4, a two-spheres system is investigated with a recently implemented PR-DNS …

Automatic Shoreline Digitization And Mesh Element Sizing For Hydrodynamic Modeling, Henok Kefelegn

LSU Doctoral Dissertations

The first and most critical step in any coastal hydrodynamics and transport process modeling is identifying land-water boundaries. In a coastal wetland, this has always been a challenge due to the complexity of the wetland and lack of efficient methods, calling for efficient and effective methods to extract and digitize the shorelines. While coastline feature extraction has been increasingly researched, its application in hydrodynamic and environmental modeling, without morphological adjustment, remains limited and suboptimal. Further, there has been a paucity of cost-effective, contextually adaptive and high-quality methods to generate meshes, especially for coastal hydrodynamic modeling. This study has developed and …

Unprepared To Be Culturally Responsive: An Examination Of Secondary Esl Educators In Rural Louisiana, Danielle Marie Butcher

LSU Doctoral Dissertations

The purpose of this study was to examine the problem of instructing English learners in a rural Louisiana district. The following questions guided this study: (1) How do the teachers perceive their pre-service and in-service training for English learners?, (2) How do the teachers perceive their ability to implement culturally responsive pedagogical practices for English learners?, (3) How do the teachers perceive the district’s approach to tangible, informational, and emotional supports for English learners?, and (4) What are the teachers’ perceptions, if any, of sociocultural inequities faced by English learners? And how, if any, do these sociocultural inequities affect the …

A Role For Oncostatin M In The Impairment Of Glucose Homeostasis In Obesity, Irene Piquer-Garcia, Laura Campderros, Siri D. Taxerås, Aleix Gavaldà-Navarro, Rosario Pardo, María Vila, Silvia Pellitero, Eva Martínez, Jordi Tarascó, Pau Moreno, Joan Villarroya, Rubén Cereijo, Lorena González, Marjorie Reyes, Silvia Rodriguez-Fernández, Marta Vives-Pi, Carles Lerin, Carrie M. Elks, Jacqueline M. Stephens, Manel Puig-Domingo, Francesc Villarroya, Josep A. Villena, David Sánchez-Infantes

Faculty Publications

© 2019 Endocrine Society 2019. Context: Oncostatin M (OSM) plays a key role in inflammation, but its regulation and function during obesity is not fully understood. Objective: The aim of this study was to evaluate the relationship of OSM with the inflammatory state that leads to impaired glucose homeostasis in obesity. We also assessed whether OSM immunoneutralization could revert metabolic disturbances caused by a high-fat diet (HFD) in mice. Design: 28 patients with severe obesity were included and stratified into two groups: (1) glucose levels /dL and (2) glucose levels >100 mg/dL. White adipose tissue was obtained to examine OSM …

Reproductive Biology And Trophic Niche Of Hardhead Catfish In The Northern Gulf Of Mexico, Lucas G. Pensinger

LSU Master's Theses

Generally, marine fishes have very high fecundity with each female producing many small eggs which hatch into small larvae. However, Ariopsis felis, a species of marine catfish common to coastal Louisiana, has low fecundity and produces the largest eggs of the teleost fishes. Despite wide range and generally high abundance, we know very little of A. felis biology and population. The few existing studies of A. felis are older and often have questionable or unclear methodology.

I examined four aspects of A. felis reproductive biology: 1) reproductive timing,

2) fecundity, 3) length at first maturity, and 4) mouth brooding. …

Development And Validation Of A Simplified Transient Two-Phase Flow Model For Any Pipe Inclination, Ligia Tornisiello

LSU Master's Theses

This study describes the development and validation of an improved simplified model for transient two-phase flow for any pipe inclination. The simplified model proposed has been validated with field-scale test well and laboratorial data, and also compared to the state-of-the-art commercial simulator for transient two-phase flow in pipes. The results of the simplified model showed an agreement within the range of ±30% for the holdup predictions for 65% of the scenarios, and an agreement within the range of ±30% for the pressure predictions for 82% of the scenarios considered in this work.

In the oil and gas industry, transient two-phase …

Concentrations, Sources And Health Risks Of Particulate Matter In Southeast Us: Current Status And Future Changes, Fenglin Han

LSU Doctoral Dissertations

Evaluation of long-term air quality trends and prediction of future air quality may help to design and demonstrate effectiveness of control strategies and guide future air quality management. As one of the six criteria air pollutants (CAPs) regulated by the US Environmental Protection Agency (EPA), particulate matter with aerodynamic diameter of 2.5 µm or less (PM_2.5) is of great interests since it has adverse effects on human health, visibility and climate. This study aims to understand the current status and future changes in concentrations, sources, and health risks of PM_2.5 in Southeast US. Firstly, observations were analyzed …

Ageism And Embodied Stereotypes: A Study Of Adult Learners In Community College At Midlife, Marla Jane Erwin

LSU Doctoral Dissertations

Adult students are generally classified as a single group for study, yet developmental psychologists recognize separate developmental periods during adulthood that suggest adult students at midlife may experience development within higher education differently that younger adult students, in part due to ageism expressed at individual, institutional and internalized levels. This project applies the concept of lifespan developmental periods to distinguish students at midlife as a focus of inquiry using a mixed method design. Twenty-nine faculty and 205 students responded to the Relating to Older People Evalution (ROPE; Cherry & Palmore, 2008) to assess self-reports of both positive and negative ageist …

Liability Of The Structural Engineer: Establishing, Quantifying, And Managing Risks, Justin Thomas Ittmann

LSU Doctoral Dissertations

Liability is an important topic to all practicing professionals—including practicing engineers. However, the topic of liability does not receive the necessary attention required relative to other professions. Further, engineers that desire to learn more about liability in relation to their practice do not have many university options within an engineering curriculum or from outside materials available to a non-legally trained engineer. The goal of the study is to provide a comprehensive overview of liability directed towards an intelligent practicing engineer, while avoiding unnecessary over-simplification of the material. This study initially provides an in depth survey of the legal standard of …

The First Complete Mitochondrial Genomes Of Sawtail Surgeonfishes (Acanthuridae: Prionurus), William B. Ludt, Luiz A. Rocha, Prosanta Chakrabarty

Faculty Publications

© 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Surgeonfishes of the family Acanthuridae are primarily large-bodied herbivores that provide critical ecosystem services to coral reefs. Five out of the six genera that comprise the family have had mitochondrial genomes sequenced, with the exception of the genus Prionurus. Here, for the first time, we assemble and annotate the mitochondrial genomes of two sawtail surgeonfishes. The circular genomes of P. biafraensis and P. laticlavius are 16,552 bp and 16,531 bp in length, respectively, and contain 13 protein-coding genes, 22 transfer RNA genes, 2 …

Obesity Medications In Development, Candida J. Rebello, Frank L. Greenway

Clinical Research Faculty Publications

Introduction: Obesity is compounded by a neurobiology that is resistant to weight loss. Therefore, the development of pharmacotherapies to address the pathology underlying the dysregulation of energy homeostasis is critical. Areas covered: This review examines selected clinical trial evidence for the pharmacologic treatment of obesity and provides an expert opinion on anti-obesity drug development. The article includes the outcomes of anti-obesity medications that have been evaluated in clinical trials but have not yet received approval from the U.S. Food and Drug Administration. The mechanisms of action of glucagon-like peptide-1 agonists and co-agonists, diabetes medications being investigated for weight loss, and …

Anthropogenic, Direct Pressures On Coastal Wetlands, A Newton, J Icely, S Cristina, G M. Perillo, A Newton, D Ashan, S Cragg, Y M. Luo, C Tu, Y Li, H B. Zhang, R Ramesh, D L. Forbes, C Solidoro, B Bejaoui, S Gao, R Pastres, H Kelsey, D Taillie, N Nhan, A C. Brito, L I. De, K U. R, C

Faculty Publications

Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal wetlands are complex social-ecological systems that occur at all latitudes, from polar regions to the tropics. This overview covers wetlands in five continents. The wetlands are of varying size, catchment size, human population and stages of economic development. Economic sectors and activities in and around the coastal wetlands and their catchments exert multiple, direct pressures. These pressures affect the state of the wetland environment, ecology and valuable ecosystem services. All the coastal wetlands were found to be affected in some …

The Resilience Of Coastal Marshes To Hurricanes: The Potential Impact Of Excess Nutrients, Y Mo, M S. Kearney, R. Eugene Turner

Faculty Publications

Hurricanes pose an increasing threat to coastal environments as the intensity and severity of hurricanes are predicted to increase under the changing climate. Coastal wetlands are effective nature-based defenses of coastal cities against storms. However, the ecosystems themselves are also susceptible to the impacts of hurricanes, which are highly complex and not fully understood. Here we utilize multi-decadal satellite data archives (Landsat 1984-2014 and MODIS 2005-2015) and long-term coast-wide field-based environmental data (1978-2018) to investigate the impacts of hurricanes Katrina (2005), Gustav (2008), and Isaac (2012) on the coastal marshes in Louisiana, USA, where the hurricanes made landfall. While the …

Effects Of Mississippi River Water On Phytoplankton Growth And Composition In The Upper Barataria Estuary, Louisiana, Ling Ren, Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

Diversion of river waters to adjacent estuaries may occur during wetland restoration, navigation channel development, or storms. We proposed that diversions of nitrogen- and phosphorus-enriched waters from the river to estuarine waters would result in increased phytoplankton biomass and shifts to noxious or harmful algal blooms. We tested this hypothesis by conducting four seasonal microcosm experiments in which Mississippi River water was mixed at different volume ratios with ambient estuarine waters of three lakes in the upper Barataria Basin, Louisiana, USA. These lakes included two brackish lakes that were in the path of diverted Mississippi River water, and a freshwater …

Soil Shear Strength Losses In Two Fresh Marshes With Variable Increases In N And P Loading, R. Eugene Turner, Christopher Swarzenski, James E. Bodker

Faculty Publications

We measured soil shear strength (SSS) from 2009 to 2018 in two hydrologically distinct freshwater marshes dominated by Panicum hemitomon after nitrogen (N) and phosphorous (P) were applied to the surface in spring. The SSS averaged over 100-cm depth in the floating and anchored marshes declined up to 30% throughout the profiles and with no apparent differences in the effects of the low, medium, and high N + P dosing. Plots with only N or P additions exhibited significant changes in SSS at individual depths below 40 cm for the anchored marsh, but not the floating marsh. The average SSS …

Geometry And Topology Of Estuary And Braided River Channel Networks Automatically Extracted From Topographic Data, Matthew Hiatt

Faculty Publications

No abstract provided.

Historical Shifts In Benthic Infaunal Diversity In The Northern Gulf Of Mexico Since The Appearance Of Seasonally Severe Hypoxia, N.N. Rabalais, M.M. Baustian

Faculty Publications

No abstract provided.

Role Of Delta-Front Erosion In Sustaining Salt Marshes Under Sea-Level Rise And Fluvial Sediment Decline, S.L. Yang, X. Luo, S. Temmerman, M. Kirwan, T. Bouma, K. Xu, S. Zhang, J. Fan, B. Shi

Faculty Publications

No abstract provided.

Influence Of Macrobenthos (Meretrix Meretrix Linnaeus) On Erosion-Accretion Processes In Intertidal Flats: A Case Study From A Cultivation Zone, B. Shi, P.D. Pratolongo, Y. Du, J. Li, S.L. Yang, J. Wu, K. Xu, Y.P. Wang

Faculty Publications

No abstract provided.