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Articles 451 - 480 of 3417

Full-Text Articles in Physical Sciences and Mathematics

Using Spatial Analysis And Machine Learning Techniques To Develop A Comprehensive Highway-Rail Grade Crossing Consolidation Model, Samira Soleimani Oct 2020

Using Spatial Analysis And Machine Learning Techniques To Develop A Comprehensive Highway-Rail Grade Crossing Consolidation Model, Samira Soleimani

LSU Doctoral Dissertations

The safety of highway-railroad grade crossings (HRGC) is still an issue in the United States of America (USA). The grade crossing is where a railroad crosses a road at the same level without any over or underpass. To improve the safety of crossings, the crossings’ condition should be explored from several aspects such as engineering design (speed limit, warning signs, etc.), road condition (number of lanes, surface markings, etc.), rail design (the type of track, ballast, etc.), temporal variables (weather, visibility, time of day, lightning, etc.), social variables (population, race, etc.), and last but not least, spatial variables (the type …

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The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson Oct 2020

The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson

LSU Master's Theses

Southern Flounder, Paralichthys lethostigma, are a coastal, estuarine-dependent flatfish species that inhabits the Southeastern US Atlantic Ocean and Gulf of Mexico. Throughout their range, Southern Flounder are exploited by both commercial and recreational fisheries. Recently, numerous sources have expressed concerns about Southern Flounder populations, with stock assessments indicating declines in spawning stock biomass and recruitment. To estimate life history traits needed for informed management, such as age, growth, and maturity, I collected 327 Southern Flounder from Louisiana and obtained 14,184 historical records from the Louisiana Department of Wildlife and Fisheries. Using a von Bertalanffy growth equation in a Bayesian …

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Ideas And Perspectives: The Same Carbon Behaves Like Different Elements - An Insight Into Position-Specific Isotope Distributions, Yuyang He, Xiaobin Cao, Huiming Bao Oct 2020

Ideas And Perspectives: The Same Carbon Behaves Like Different Elements - An Insight Into Position-Specific Isotope Distributions, Yuyang He, Xiaobin Cao, Huiming Bao

Faculty Publications

It is expected that information on the source, reaction pathway, and reaction kinetics of an organic compound can be obtained from its position-specific isotope compositions or intramolecular isotope distribution (Intra-ID). To retrieve the information, we could use its predicted equilibrium Intra-ID as a reference for understanding the observed Intra-IDs. Historically, observed, apparently close-to-equilibrium carbon Intra-ID has prompted an open debate on the nature of biosystems and specifically the pervasiveness of reversible biochemical reactions. Much of the debate remains unresolved, and the discussion has not clearly distinguished between two states of equilibrium: (1) the equilibrium among the corresponding bond-breaking and bond-forming …

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Preface For Article Collection "Evolution And Variability Of Asian Monsoon And Its Linkage With Cenozoic Global Cooling", Ryuji Tada, Christian Betzler, Peter D. Clift Oct 2020

Preface For Article Collection "Evolution And Variability Of Asian Monsoon And Its Linkage With Cenozoic Global Cooling", Ryuji Tada, Christian Betzler, Peter D. Clift

Faculty Publications

No abstract provided.

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Environmentally Clean Access To Antarctic Subglacial Aquatic Environments, Alexander B. Michaud, Trista (Vick-Majors, Amanda M. Achberger, Mark L. Skidmore, Brent C. Christner, Martyn Tranter, John C. Priscu Oct 2020

Environmentally Clean Access To Antarctic Subglacial Aquatic Environments, Alexander B. Michaud, Trista (Vick-Majors, Amanda M. Achberger, Mark L. Skidmore, Brent C. Christner, Martyn Tranter, John C. Priscu

Faculty Publications

Subglacial Antarctic aquatic environments are important targets for scientific exploration due to the unique ecosystems they support and their sediments containing palaeoenvironmental records. Directly accessing these environments while preventing forward contamination and demonstrating that it has not been introduced is logistically challenging. The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project designed, tested and implemented a microbiologically and chemically clean method of hot-water drilling that was subsequently used to access subglacial aquatic environments. We report microbiological and biogeochemical data collected from the drilling system and underlying water columns during sub-ice explorations beneath the McMurdo and Ross ice shelves and …

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Tidal And Storm Impacts On Hydrodynamics And Sediment Dynamics In An Energetic Ebb Tidal Delta, Kehui Xu, P. Ansley Wren, Yanxia Ma Oct 2020

Tidal And Storm Impacts On Hydrodynamics And Sediment Dynamics In An Energetic Ebb Tidal Delta, Kehui Xu, P. Ansley Wren, Yanxia Ma

Faculty Publications

Bottom-mounted instrumentation was deployed at two sites on a large sandy shoal of an ebb tidal delta offshore of the Port Royal Sound of South Carolina of USA to collect hydrodynamics and sediment dynamics data. One site ("borrow site") was 2 km offshore in a dredge pit for nearby beach nourishment and the other site ("reference site") was 10 km offshore. In situ time-series data were collected during two periods after the dredging: 15 March-12 June (spring) and 18 August-18 November (fall) of 2012. Data at the reference site indicated active migrating bedforms from centimeters to decimeters tall, and sediment …

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The Dynamic Trophic Niche Of An Island Bird Of Prey, Ulises Balza, Nicolas A. Lois, Michael J. Polito, Klemens Puetz, Amira Saalom, Andrea Raya Rey Oct 2020

The Dynamic Trophic Niche Of An Island Bird Of Prey, Ulises Balza, Nicolas A. Lois, Michael J. Polito, Klemens Puetz, Amira Saalom, Andrea Raya Rey

Faculty Publications

Optimal foraging theory predicts an inverse relationship between the availability of preferred prey and niche width in animals. Moreover, when individuals within a population have identical prey preferences and preferred prey is scarce, a nested pattern of trophic niche is expected if opportunistic and selective individuals can be identified. Here, we examined intraspecific variation in the trophic niche of a resident population of striated caracara (Phalcoboenus australis) on Isla de los Estados (Staten Island), Argentina, using pellet and stable isotope analyses. While this raptor specializes on seabird prey, we assessed this population's potential to forage on terrestrial prey, especially invasive …

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Fish Assemblages Associated With Artificial Reefs Assessed Using Multiple Gear Types In The Northwest Gulf Of Mexico, Jeffrey D. Plumlee, Kaylan M. Dance, Michael A. Dance, Hay R. Rooker, Thomas C. Tinhan, J. Brooke Shipley, R. J. David Wells Oct 2020

Fish Assemblages Associated With Artificial Reefs Assessed Using Multiple Gear Types In The Northwest Gulf Of Mexico, Jeffrey D. Plumlee, Kaylan M. Dance, Michael A. Dance, Hay R. Rooker, Thomas C. Tinhan, J. Brooke Shipley, R. J. David Wells

Faculty Publications

Quantitative surveys of fishes associated with artificial reefs in the northwest Gulf of Mexico were conducted over a 4-yr period (2014-2017). Artificial reefs surveyed were comprised of three types: concrete structures, rig jackets, and decommissioned ships. All reefs were surveyed using vertical long line ( VLL), fish traps, and Adaptive Resolution Imaging Sonar (ARIS 1800). Mean fish abundance did not significantly differ using VLL [1.7 ind set(-1) (SD 2.2)] among the three reef types. However, relative abundance among all fishes collected was significantly highest on rig reefs using traps [6.2 ind soak(-1) (SD 3.8)], while results from sonar surveys indicated …

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All-Atomic Molecular Dynamic Studies Of Human And Drosophila Cdk8: Insights Into Their Kinase Domains, The Lxxll Motifs, And Drug Binding Site, Wu Xu, Xiao-Jun Xie, Ali K. Faust, Mengmeng Liu, Xiao Li, Feng Chen, Ashlin A. Naquin, Avery C. Walton, Peter W. Kishbaugh, Jun-Yuan Ji Oct 2020

All-Atomic Molecular Dynamic Studies Of Human And Drosophila Cdk8: Insights Into Their Kinase Domains, The Lxxll Motifs, And Drug Binding Site, Wu Xu, Xiao-Jun Xie, Ali K. Faust, Mengmeng Liu, Xiao Li, Feng Chen, Ashlin A. Naquin, Avery C. Walton, Peter W. Kishbaugh, Jun-Yuan Ji

Faculty Publications

Cyclin-dependent kinase 8 (CDK8) and its regulatory partner Cyclin C (CycC) play conserved roles in modulating RNA polymerase II (Pol II)-dependent gene expression. To understand the structure and function relations of CDK8, we analyzed the structures of human and Drosophila CDK8 proteins using molecular dynamics simulations, combined with functional analyses in Drosophila. Specifically, we evaluated the structural differences between hCDK8 and dCDK8 to predict the effects of the LXXLL motif mutation (AQKAA), the P154L mutations, and drug binding on local structures of the CDK8 proteins. First, we have observed that both the LXXLL motif and the kinase activity of CDK8 …

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Quantum Backaction Cancellation In The Audio Band, Jonathan Cripe, Torrey Cullen, Yanbei Chen, Paula Heu, David Follman, Garrett D. Cole, Thomas Corbitt Sep 2020

Quantum Backaction Cancellation In The Audio Band, Jonathan Cripe, Torrey Cullen, Yanbei Chen, Paula Heu, David Follman, Garrett D. Cole, Thomas Corbitt

Faculty Publications

We report on the cancellation of quantum backaction noise in an optomechanical cavity. We perform measurements of the displacement of the microresonator, one in reflection of the cavity and one in transmission of the cavity. We show that measuring the amplitude quadrature of the light transmitted by the optomechanical cavity allows us to cancel the backaction noise between 2 and 50 kHz as a consequence of the strong optical spring present in the detuned cavity. This cancellation yields a more sensitive measurement of the microresonator's position with a 2 dB increase in sensitivity. To confirm that the backaction is eliminated, …

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Weather Derivatives And The Market Price Of Risk, Julius Esunge, James J. Njong Sep 2020

Weather Derivatives And The Market Price Of Risk, Julius Esunge, James J. Njong

Journal of Stochastic Analysis

No abstract provided.

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Effect Of Oxidation Level On The Interfacial Water At The Graphene Oxide-Water Interface: From Spectroscopic Signatures To Hydrogen-Bonding Environment, Rolf David, Aashish Tuladhar, Le Zhang, Christopher Arges, Revati Kumar Sep 2020

Effect Of Oxidation Level On The Interfacial Water At The Graphene Oxide-Water Interface: From Spectroscopic Signatures To Hydrogen-Bonding Environment, Rolf David, Aashish Tuladhar, Le Zhang, Christopher Arges, Revati Kumar

Faculty Publications

The interfacial region of the graphene oxide (GO)-water system is nonhomogenous due to the presence of two distinct domains: an oxygen-rich surface and a graphene-like region. The experimental vibrational sum-frequency generation (vSFG) spectra are distinctly different for the fully oxidized GO-water interface as compared to the reduced GO-water case. Computational investigations using ab initio molecular dynamics were performed to determine the molecular origins of the different spectroscopic features. The simulations were first validated by comparing the simulated vSFG spectra to those from the experiment, and the contributions to the spectra from different hydrogen bonding environments and interfacial water orientations were …

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Exchangeably Weighted Bootstraps Of Martingale Difference Arrays Under The Uniformly Integrable Entropy, Salim Bouzebda, Nikolaos Limnios Sep 2020

Exchangeably Weighted Bootstraps Of Martingale Difference Arrays Under The Uniformly Integrable Entropy, Salim Bouzebda, Nikolaos Limnios

Journal of Stochastic Analysis

No abstract provided.

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On An Asset Model Of Hobson-Rogers Type, Narn-Rueih Shieh Sep 2020

On An Asset Model Of Hobson-Rogers Type, Narn-Rueih Shieh

Journal of Stochastic Analysis

No abstract provided.

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The Life And Death And Consequences Of Canals And Spoil Banks In Salt Marshes, R. Eugene Turner, Erick M. Swenson Sep 2020

The Life And Death And Consequences Of Canals And Spoil Banks In Salt Marshes, R. Eugene Turner, Erick M. Swenson

Faculty Publications

We describe the consequence and demise of levees (spoil banks) built from dredging canals in Louisiana salt marshes using morphometric measurements made over 30 years, soil collections on the spoil bank and in the salt marshes behind, and complementary observations from other areas. These measurements were used to determine the temporal bounds of how long spoil banks last and if salt marsh soils remaining in salt marshes are affected. If the rates of changes in spoil bank morphology continue, then the estimated life time of the shrub-tree vegetation at a representative spoil bank is 81 years, the spoil bank width …

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Potential Pollen Evidence For The 1933 M 7.5 Diexi Earthquake And Implications For Post-Seismic Landscape Recovery, Hongyan Xu, Hanchao Jiang, Kam-Biu Liu, Ning Zhong Sep 2020

Potential Pollen Evidence For The 1933 M 7.5 Diexi Earthquake And Implications For Post-Seismic Landscape Recovery, Hongyan Xu, Hanchao Jiang, Kam-Biu Liu, Ning Zhong

Faculty Publications

The relationships between strong earthquakes, landslides, and vegetation destruction and the process of post-seismic recovery in tectonically active alpine valley areas have not been adequately documented. Here we show detailed pollen study results from a swamp located near the epicenter of the 1933 M 7.5 Diexi earthquake in eastern Qinghai-Tibetan Plateau (QTP) to reveal the impact of earthquake on vegetation, and the post-seismic recovery process. Based on(210)Pb-Cs-137 age model, the seismic event layer is well constrained. The earthquake event corresponds stratigraphically to a zone with the lowest pollen concentrations, the lowest pollen diversity, and a high frequency of non-arboreal pollen. …

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Optical Properties Using Adaptive Selection Of Nir/Swir Reflectance Correction And Quasi-Analytic Algorithms For The Modis-Aqua In Estuarine-Ocean Continuum: Application To The Northern Gulf Of Mexico, Ishan D. Joshi, Eurico J. D'Sa Sep 2020

Optical Properties Using Adaptive Selection Of Nir/Swir Reflectance Correction And Quasi-Analytic Algorithms For The Modis-Aqua In Estuarine-Ocean Continuum: Application To The Northern Gulf Of Mexico, Ishan D. Joshi, Eurico J. D'Sa

Faculty Publications

An adaptive selection of the near/shortwave infrared (NIR/SWIR) reflectance correction and the quasi-analytic algorithms (QAAs) is proposed for the Moderate Resolution Imaging Spectroradiometer (MODIS-Aqua) to utilize the strengths of different correction algorithms and QAAs in a single satellite scene with water types ranging from turbid coastal to clear open ocean waters. A blended satellite product is generated by merging three atmospheric-correction algorithms(AD-ATCOR): 1) iterative NIR correction; 2) management unit of the north sea mathematical models (MUMM); and 3) SWIR, using a spectral threshold-based selection for different water types. The validation analysis of a blended remote sensing reflectance product showed overall …

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Tropical Cyclone Landfall Frequency And Large-Scale Environmental Impacts Along Karstic Coastal Regions (Yucatan Peninsula, Mexico), Victor H. Rivera-Monroy, Luis M. Farfan, Luis Brito-Castillo, Jorge Cortes-Ramos, Eduardo Gonzalez-Rodriguez, Eurico D'Sa, Jorge I. Euan-Avila Sep 2020

Tropical Cyclone Landfall Frequency And Large-Scale Environmental Impacts Along Karstic Coastal Regions (Yucatan Peninsula, Mexico), Victor H. Rivera-Monroy, Luis M. Farfan, Luis Brito-Castillo, Jorge Cortes-Ramos, Eduardo Gonzalez-Rodriguez, Eurico D'Sa, Jorge I. Euan-Avila

Faculty Publications

Tropical cyclones (TCs) are natural systems that develop over ocean basins and are key components of the atmospheric activity during the warm season. However, there are still knowledge gaps about the combined positive and negative TC impacts on the structure and function of coastal socio-ecosystems. Using remote sensing tools, we analyzed the frequency, trajectory, and intensity of 1894 TCs from 1851-2019 to identify vulnerable "hotspots" across the Yucatan Peninsula (YP), Mexico. A total of 151 events hit the YP, with 96% of landings on the eastern coast. We focused on three major hurricanes (Emily and Wilma, 2005; Dean, 2007) and …

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Seasonal Infilling And Sedimentary Characteristics In Sandy Versus Muddy Coastal Borrow Areas On The Louisiana Continental Shelf, Usa, Matthew Barley Aug 2020

Seasonal Infilling And Sedimentary Characteristics In Sandy Versus Muddy Coastal Borrow Areas On The Louisiana Continental Shelf, Usa, Matthew Barley

LSU Master's Theses

Offshore sand deposits on the Louisiana Continental Shelf, such as inner shelf shoals and buried paleo-river channels, can be excavated to restore beaches and barrier islands that are rapidly deteriorating due to subsidence, sea-level rise and deficits in coastal sediment supply. Presented here is grain size, x-radiograph, and Beryllium-7 (7Be) derived sedimentation rates from multicores (~ 50 cm depth) retrieved from borrow areas (BAs) in contrasting depositional settings, all of which have implications for management of water quality, seafloor sedimentology, and biogeochemistry in proximal areas. Multicores were retrieved in fall 2018 at Caminada BA — a sandy energetic …

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Hydrodynamics, Sediment Transport, And Water Quality Of Two Contrasting Dredge Pits On The Louisiana Shelf, Robert Bales Aug 2020

Hydrodynamics, Sediment Transport, And Water Quality Of Two Contrasting Dredge Pits On The Louisiana Shelf, Robert Bales

LSU Master's Theses

Sediment is needed for coastal restoration in Louisiana and is often excavated offshore from both mud-capped and sandy dredge pits. The mined sand from mud-capped pits, like Sandy Point which is west of modern Mississippi Delta of Louisiana, was originally from a paleo river channel and later covered by mud from modern coastal processes. Sandy pits, like Caminada pit in eastern Ship Shoal on Louisiana shelf, generally experience higher energy conditions. To better understand the post-dredging effects on hydrodynamics, sediment transport, and water quality, two tripods were deployed at Caminada and Sandy Point pits in summer 2018 and 2019, respectively, …

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Protein Discrimination Using A Fluorescence-Based Sensor Array Of Thiacarbocyanine-Gumbos, Rocio L. Perez, Mingyan Cong, Stephanie R. Vaughan, Caitlan E. Ayala, Waduge Indika S. Galpothdeniya, John K. Mathaga, Isiah M. Warner Aug 2020

Protein Discrimination Using A Fluorescence-Based Sensor Array Of Thiacarbocyanine-Gumbos, Rocio L. Perez, Mingyan Cong, Stephanie R. Vaughan, Caitlan E. Ayala, Waduge Indika S. Galpothdeniya, John K. Mathaga, Isiah M. Warner

Faculty Publications

Sensitive and selective detection of proteins from complex samples has gained substantial interest within the scientific community. Early and precise detection of key proteins plays an important role in potential clinical diagnosis, treatment of different diseases, and proteomic research. In the study reported here, six different compounds belonging to a group of uniform materials based on organic salts (GUMBOS) have been synthesized using three thiacarbocyanine (TC) dyes and employed as fluorescent sensors. Fluorescence properties of micro- and nanoaggregates of these TC-based GUMBOS formed in phosphate buffer solutions are studied in the absence and presence of seven proteins. Fluorescence response patterns …

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Nonparametric Recursive Method For Kernel-Type Function Estimators For Censored Data, Salim Bouzebda, Yousri Slaoui Aug 2020

Nonparametric Recursive Method For Kernel-Type Function Estimators For Censored Data, Salim Bouzebda, Yousri Slaoui

Journal of Stochastic Analysis

No abstract provided.

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Modeling Anatomic Changes For Adaptive Radiotherapy In Locally Advanced Lung Cancer Patient Population, James Alexander Kavanaugh Aug 2020

Modeling Anatomic Changes For Adaptive Radiotherapy In Locally Advanced Lung Cancer Patient Population, James Alexander Kavanaugh

LSU Doctoral Dissertations

Anatomic changes occurring mid-treatment for patients undergoing radiation therapy for locally advanced lung cancer can degrade the quality of the intended treatment plan. These changes include tumor regression, geometric misalignment, and lung density changes (atelectasis and pleural effusion), and are visible on the daily 3D cone beam CT (CBCT). To maintain the intended treatment quality, adaptive radiotherapy (ART) can be employed to modify the treatment plan to account for these anatomic changes. However, the evaluation on when to adapt is currently completed manually by the treating clinicians, resulting in a subjective and inconsistent application. To address these limitations, a series …

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General Product Formula Of Multiple Integrals Of Lévy Process, Nishant Agrawal, Yaozhong Hu, Neha Sharma Aug 2020

General Product Formula Of Multiple Integrals Of Lévy Process, Nishant Agrawal, Yaozhong Hu, Neha Sharma

Journal of Stochastic Analysis

No abstract provided.

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Continuous Dependence On The Coefficients For Mean-Field Fractional Stochastic Delay Evolution Equations, Brahim Boufoussi, Salah Hajji Aug 2020

Continuous Dependence On The Coefficients For Mean-Field Fractional Stochastic Delay Evolution Equations, Brahim Boufoussi, Salah Hajji

Journal of Stochastic Analysis

No abstract provided.

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Transition Metal Complexes Of Pyridyltriazole And Bipyridine Ligands, Sen Gao Aug 2020

Transition Metal Complexes Of Pyridyltriazole And Bipyridine Ligands, Sen Gao

LSU Doctoral Dissertations

Four Ni(II) complexes have been obtained with the pyridyltriazole ligand, bpt, or the bis(pyridyltriazole) ligand, m-xpt, in chapter 2. This work was carried out as a comparison with the previously established coordination chemistry of copper(II) with bpt and m-xpt. Initially, the reaction between Ni(II) and bpt only produced one mononuclear compound, [Ni(bpt)2(H2O)2](NO3)2 (1). In order to study the formation of Ni-bpt and Ni-m-xpt complexes in solution, mixtures of Ni(NO3)2 and ligand (m-xpt or bpt) were prepared in different ratios and …

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Modifications To Gravitational Wave Equation From Canonical Quantum Gravity, Andrea Dapor, Klaus Liegener Aug 2020

Modifications To Gravitational Wave Equation From Canonical Quantum Gravity, Andrea Dapor, Klaus Liegener

Faculty Publications

It is expected that the quantum nature of spacetime leaves its imprint in all semiclassical gravitational systems, at least in certain regimes, including gravitational waves. In this paper we investigate such imprints on gravitational waves within a specific framework: space is assumed to be discrete (in the form of a regular cubic lattice), and this discrete geometry is quantised following Dirac's canonical quantisation scheme. The semiclassical behavior is then extracted by promoting the expectation value of the Hamiltonian operator on a semiclassical state to an effective Hamiltonian. Considering a family of semiclassical states representing small tensor perturbations to Minkowski background, …

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Second Harmonic Generation Spectroscopy And Microscopy Of Liposomes, Nanoparticles, And Cells, Prakash Hamal Aug 2020

Second Harmonic Generation Spectroscopy And Microscopy Of Liposomes, Nanoparticles, And Cells, Prakash Hamal

LSU Doctoral Dissertations

Second harmonic generation (SHG) is used to investigate the factors that impact nanoparticle-based drug-delivery applications. In the first study, molecular adsorption and transport kinetics of a positively-charged dye, malachite green isothiocyanate (MGITC), is characterized at the surface of different colloidal liposomes in water using SHG spectroscopy. The molecular interactions of MGITC is compared to our previous investigations with malachite green (MG). In comparison to MG, MGITC demonstrates stronger adsorption and faster transport through lipid membranes. Correspondingly, the SHG experimental results are in excellent agreement with the molecular dynamics (MD) simulations results. A key finding illustrates the importance of functional groups, …

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The Value Of Information Under Partial Information For Exponential Utility, Farai Julius Mhlanga, Mbakisi Dube Aug 2020

The Value Of Information Under Partial Information For Exponential Utility, Farai Julius Mhlanga, Mbakisi Dube

Journal of Stochastic Analysis

No abstract provided.

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Probing The Surface Acidity Of Supported Aluminum Bromide Catalysts, Md Ashraful Abedin, Swarom Kanitkar, Nitin Kumar, Zi Wang, Kunlun Ding, Graham Hutchings, James J. Spivey Aug 2020

Probing The Surface Acidity Of Supported Aluminum Bromide Catalysts, Md Ashraful Abedin, Swarom Kanitkar, Nitin Kumar, Zi Wang, Kunlun Ding, Graham Hutchings, James J. Spivey

Faculty Publications

Solid acid catalysis is an important class of reactions. The principal advantages of solid acid catalysts as compared to their corresponding fluid acids include minimal waste and ease of product separation. One type of these catalysts is based on aluminum bromide (Al2Br6), which is a stronger Lewis acid than Al2Cl6. In this report, Al(2)Br(6)is grafted on commercial mesoporous silica (CMS), SBA-15 and silica gel to create a solid catalyst similar to the silica-supported Al(2)Cl(6)superacid. These supported Al(2)Br(6)catalysts were characterized by NH3-Temperature Programmed Desorption (TPD), pyridine Diffuse Reflectance for Infrared Fourier Transform Spectroscopy (DRIFTS) and Magic Angle Spinning Nuclear Magnetic Resonance …

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