Digital Commons Network^™

Corrosion Management System Of Regional Reinforced Concrete (Rc) Bridges, Homero Castaneda, Ayman Okeil

Publications

Civil infrastructure assets, including buildings, transportation networks, energy grids and networks, and water-sewer systems, are critical functional components of day-to-day life activity in a modern society. The durability and reliability of these civil infrastructures are largely affected by corrosion-induced structural deterioration. In addition to continual use and increasing traffic demands, natural environmental conditions set degradation due to corrosion damage as a critical condition to durable and reliable infrastructures. Therefore, in order to improve the durability of the bridge infrastructures affected by corrosion in the most efficient manor, we propose a procedure/methodology to manage integrity of corroding RC bridges which is …

Development Of A Low Power, Low Cost Rural Railway Intersection Smart Detection And Warning System, Sara Ahmed, Samer Dessouky, Raymond Downing

Publications

This project explores a different approach to provide preemptive warning for train detection at grade-crossings to increase safety and reduce motor vehicle congestion. The development of a novel, low cost, low power, and off rail right-of-way (ROW) detection and warning system will be presented. A background of track circuits, which is the rail industries standard for train detection, will also be provided to highlight the benefits and challenges of the rail industry installing a system at every grade-crossings that lack any type of active warning. The benefits of using thermal imaging instead of traditional video for computer vision will also …

A Numerical Investigation Of Salinity Variations In The Barataria Estuary, Louisiana In Connection With The Mississippi River And Restoration Activities, Yanda Ou, Z. George Xue, Chunyan Li, Kehui Xu, John R. White, Samuel J. Bentley, Zhengchen Zang

Faculty Publications

© 2020 Elsevier Ltd A three-dimensional numerical model was applied to the Barataria Estuary in the Northern Gulf of Mexico to study its salinity variations as well as the impacts from the Mississippi River discharges and proposed river diversions. Model-observation comparison showed that the model was able to reproduce the hydrodynamic fields on subtidal to seasonal time scales. Salinity in the Barataria Estuary was high in fall and low in summer, with a greater variability in the lower estuary than the upper estuary. While salinity in the upper estuary was controlled by discharges from a local freshwater diversion, salinity in …

Simulating Hydrological Connectivity And Water Age Within A Coastal Deltaic Floodplain Of The Mississippi River Delta, Alexandra Christensen, Robert R. Twilley, Clinton S. Willson, Edward Castañeda-Moya

Faculty Publications

Located at the mouth of large rivers, coastal deltaic floodplains are important ecosystems for trapping sediment and removing excess nitrogen introduced to the river through agricultural and urban runoff. Hydrological connectivity (the percent of river channel water interacting with floodplain wetlands), water age (the time elapsed since water entered the system via the main river channel) and water temperature have strong impacts on the biogeochemical processes controlling the fate of sediment and nutrients at continental margins. A Delft3D hydrodynamic model was used to explore the role of river and tide forcings, hydrogeomorphology, and vegetation roughness on hydrological connectivity, water age, …

The Exemplary Spartacus: Reception, Adaptation, And Reconstruction, Benjamin Franklin Howland

LSU Doctoral Dissertations

My project, “The Exemplary Spartacus: Reception, Adaptation, and Reconstruction,” focusses on various representations of the gladiator Spartacus. I assert that Spartacus has almost exclusively been and continues to be an exemplary figure, with an extensive and connected literary tradition, working as an empty signifier in differing temporalities and localities. I draw specific attention to a core issue in the study of Spartacus, namely, the plethora of modern representations of Spartacus in various genres, and the continuing influence these representations exert through their blurring of the historical figure with local themes and ideologies. Each draw from the same ancient sources, infusing …

On The Stress Concentration At Sharp V-Notches Under Tension, Trent Mattieu Andrus

LSU Master's Theses

Accurately determining stresses at re-entrant corners using finite element analysis (FEA) is challenging due to the high stresses produced at the corner. Indeed, FEA is unable to obtain quantitatively accurate peak stresses at mathematically sharp re-entrant corners with traditional boundary conditions because these stresses are singular. Imposing a local corner radius by rounding the sharp corner to remove the singular result is an appropriate technique for large radii, but as the corner radius tends to zero and the notch is close to being sharp, we expect there are radii that yield quantitatively inaccurate results with traditional FEA. We seek to …

Indeterminate Sample Sequencing In Virtual Reality, Chase Mitchusson

LSU Doctoral Dissertations

The VR Sequencer is a tool for composing and performing music which takes advantage of spatial configuration of 3-D objects to generate looping sequences. This project combines dice-rolling with omnidirectional playheads and variable terrain to make a sequencer with indeterminate features in Virtual Reality (VR). A comparison of mapping systems for music games and digital instruments demonstrates a middle ground for interactive music making which the VR Sequencer applies. An inspection of current VR works exhibits a disconnect be- tween VR gamers and experimental musicians. In an attempt to give the gaming community access to experimental music making, the VR …

Molecular Motions Of Acetonitrile Molecules In The Solvation Shell Of Lithium Ions, Xiaobing Chen, Daniel G. Kuroda

Faculty Publications

© 2020 Author(s). Lithium ion solutions in organic solvents have become ubiquitous because of their use in energy storage technologies. The widespread use of lithium salts has prompted a large scientific interest in elucidating the molecular mechanisms, giving rise to their macroscopic properties. Due to the complexity of these molecular systems, only few studies have been able to unravel the molecular motions and underlying mechanisms of the lithium ion (Li+) solvation shell. Lately, the atomistic motions of these systems have become somewhat available via experiments using ultrafast laser spectroscopies, such as two-dimensional infrared spectroscopy. However, the molecular mechanism behind the …

Verbal Response Inhibition And Stuttering In Adults, Shanley Belle Treleaven

LSU Doctoral Dissertations

Many adults who stutter (AWS) attempt to modify or suppress their stuttered speech daily. The ability to effectively suppress motoric behavior after initiation relies on executive functions such as inhibition – specifically verbal inhibition – a challenging task regardless of clinical status. Minimal published data are available about verbal inhibition in non-stuttering adults, and no data are available for AWS. Researchers have reported slower inhibition for AWS during manual tasks, but inconsistent relationships have been found between manual and verbal inhibition. It is often presumed that inhibition differences in AWS, if detected, would be associated with greater difficulties suppressing the …

From Regulation Of Secondary Metabolites To Increased Virulence Under Sublethal Dosage Of Antibiotics: An Unprecedented Role Of Global Regulator, Mftr, In Burkholderia Thailandensis, Sudarshan Singh Thapa

LSU Doctoral Dissertations

The rise of multi-drug resistant bacteria combined with a decreasing pool of effective antibiotics has placed an increasing need for the development of novel antibiotics. Bacterial natural products or secondary metabolites have been the greatest source for development of novel antibiotics. The genus Burkholderia has recently emerged as a source of promising compounds with antibacterial, antifungal, and anti-cancer activities. Bacterial secondary metabolites provide added advantage to bacteria under stressful environments such as during host infection, evading predators or nutrient deficient conditions. However, genes involved in synthesis of these novel compounds remain silent under normal laboratory growth, creating a hurdle in …

Spherically Symmetric Loop Quantum Gravity: Analysis Of Improved Dynamics, Rodolfo Gambini, Javier Olmedo, Jorge Pullin

Faculty Publications

We study the 'improved dynamics' for the treatment of spherically symmetric space-times in loop quantum gravity introduced by Chiou et al in analogy with the one that has been constructed by Ashtekar, Pawlowski and Singh for the homogeneous space-times. In this dynamics the polymerization parameter is a well motivated function of the dynamical variables, reflecting the fact that the quantum of area depends on them. Contrary to the homogeneous case, its implementation does not trigger undesirable physical properties. We identify semiclassical physical states in the quantum theory and derive the corresponding effective semiclassical metrics. We then discuss some of their …

Demonstration Of Dynamic Thermal Compensation For Parametric Instability Suppression In Advanced Ligo, T. Hardwick, V. J. Hamedan, C. Blair, A. C. Green, D. Vander-Hyde

Faculty Publications

Advanced LIGO and other ground-based interferometric gravitational-wave detectors use high laser power to minimize shot noise and suspended optics to reduce seismic noise coupling. This can result in an opto-mechanical coupling which can become unstable and saturate the interferometer control systems. The severity of these parametric instabilities scales with circulating laser power and first hindered LIGO operations in 2014. Static thermal tuning and active electrostatic damping have previously been used to control parametric instabilities at lower powers but are insufficient as power is increased. Here we report the first demonstration of dynamic thermal compensation to avoid parametric instability in an …

A Vaccine Targeting The Rbd Of The S Protein Of Sars-Cov-2 Induces Protective Immunity, Jingyun Yang, Wei Wang, Zimin Chen, Shuaiyao Lu, Fanli Yang, Zhenfei Bi, Linlin Bao, Fei Mo, Xue Li, Yong Huang, Weiqi Hong, Yun Yang, Yuan Zhao, Fei Ye, Sheng Lin, Wei Deng, Hua Chen, Hong Lei, Ziqi Zhang, Min Luo, Hong Gao, Yue Zheng, Yanqiu Gong, Xiaohua Jiang, Yanfeng Xu, Qi Lv, Dan Li, Manni Wang, Fengdi Li, Shunyi Wang, Guanpeng Wang, Pin Yu, Yajin Qu, Li Yang

Division of Basic Science Faculty Publications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a respiratory disease called coronavirus disease 2019 (COVID-19), the spread of which has led to a pandemic. An effective preventive vaccine against this virus is urgently needed. As an essential step during infection, SARS-CoV-2 uses the receptor-binding domain (RBD) of the spike protein to engage with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells1,2. Here we show that a recombinant vaccine that comprises residues 319–545 of the RBD of the spike protein induces a potent functional antibody response in immunized mice, rabbits and non-human primates (Macaca mulatta) as early as 7 …

Parallel And Asynchronous Distributed Optimization For Power Systems Operation, Ali Mohammadi

LSU Doctoral Dissertations

Distributed optimization approaches are gaining more attention for solving power systems energy management functions, such as optimal power flow (OPF). Preserving information privacy of autonomous control entities and being more scalable than centralized approaches are two primary reasons for developing distributed algorithms. Moreover, distributed/ decentralized algorithms potentially increase power systems reliability against failures of components or communication links.

In this dissertation, we propose multiple distributed optimization algorithms and convergence performance enhancement techniques to solve the OPF problem. We present a multi-level optimization algorithm, based on analytical target cascading, to formulate and solve a collaborative transmission and distribution OPF problem. This …

Prdm16 Deficiency Leads To Age-Dependent Cardiac Hypertrophy, Adverse Remodeling, Mitochondrial Dysfunction, And Heart Failure, Dasan Mary Cibi, Kathleen Wung Bi-Lin, Shamini Guna Shekeran, Reddemma Sandireddy, Nicole Tee, Anamika Singh, Yajun Wu, Dinesh Kumar Srinivasan, Jean Paul Kovalik, Sujoy Ghosh, Patrick Seale, Manvendra K. Singh

Division of Basic Science Faculty Publications

Hypertrophic cardiomyopathy (HCM) is a well-established risk factor for cardiovascular mortality worldwide. Although hypertrophy is traditionally regarded as an adaptive response to physiological or pathological stress, prolonged hypertrophy can lead to heart failure. Here we demonstrate that Prdm16 is dispensable for cardiac development. However, it is required in the adult heart to preserve mitochondrial function and inhibit hypertrophy with advanced age. Cardiac-specific deletion of Prdm16 results in cardiac hypertrophy, excessive ventricular fibrosis, mitochondrial dysfunction, and impaired metabolic flexibility, leading to heart failure. We demonstrate that Prdm16 and euchromatic histone-lysine N-methyltransferase factors (Ehmts) act together to reduce expression of fetal genes …

Novel Information About The Kinetic Effects Of Equine Shoe Modifications And Kinematic Effects Of Human Digital Devices For Improved Performance In Both Species, Pengju Wang

LSU Master's Theses

Equine shoes are frequently modified to enhance traction for horses that travel on paved surfaces for work, pleasure, or entertainment. Little is known about other common shoe modifications used to enhance traction like calks, tungsten carbide granules, or plastic composition. This information is vital to shoe design to protect the safety and welfare of all service, working, and leisure horses. The objective of the first part of this thesis was to quantify the effect of shoes with and without traction adaptions on kinetic measures in non-lame, light breed horses at a trot. Kinetic data was collected with a force platform …

Comparison Of High-Tech Augmentative And Alternative Communication Interfaces: Do Age And Technology Experience Matter?, Surani Gopika Nakkawita

LSU Doctoral Dissertations

Previous research has demonstrated that individuals with stroke-induced aphasia can use augmentative and alternative communication (AAC) when they cannot meet their communication needs using spoken language (Dietz, Weissling, Griffith, McKelvey, & Macke, 2014; Purdy & Van Dyke, 2011). Of the various interfaces found in the different AAC systems, the grid display and the visual scene display (VSD) have been used by individuals with aphasia (Hough & Johnson, 2009; Dietz et al., 2018). However, there is a scarcity of research examining the comparative usefulness of these interfaces.

This prospective study attempted to understand how neurologically healthy individuals of different ages and …

Bruce Gates: A Career In Catalysis, Cawas Cooper, Kerry M. Dooley, Juan C. Fierro-Gonzalez, Javier Guzman, Rolf Jentoft, H. Henry Lamb, Isao Ogino, Ron C. Runnebaum, Ajit Sapre, Alper Uzun

Faculty Publications

On the occasion of his 80th birthday, we take stock of the remarkable and ongoing career of Professor Bruce C. Gates. This Account highlights his key scientific achievements in three areas of significance: supported metal clusters and atomically dispersed metal complexes, hydroprocessing reaction networks and catalysts, and strong acid catalysis. His contributions in all three areas are noteworthy and have been sustained over 50 years. The work of his group evolved from mainly catalyst synthesis and reaction studies to also incorporate sophisticated characterization techniques based on X-ray absorption spectroscopies and improved scanning transmission electron microscopic examination of catalytic surfaces. In …

Adaptive Data Migration In Load-Imbalanced Hpc Applications, Parsa Amini

LSU Doctoral Dissertations

Distributed parallel applications need to maximize and maintain computer resource utilization and be portable across different machines. Balanced execution of some applications requires more effort than others because their data distribution changes over time. Data re-distribution at runtime requires elaborate schemes that are expensive and may benefit particular applications.

This dissertation discusses a solution for HPX applications to monitor application execution with APEX and use AGAS migration to adaptively redistribute data and load balance applications at runtime to improve application performance and scaling behavior. This dissertation provides evidence for the practicality of using the Active Global Address Space as is …

Distribution Of Aromatase In The Brain Of The African Cichlid Fish Astatotilapia Burtoni: Aromatase Expression, But Not Estrogen Receptors, Varies With Female Reproductive-State, Karen P. Maruska, Julie M. Butler, Chase Anselmo, Ganga Tandukar

Faculty Publications

© 2020 Wiley Periodicals, Inc. Estrogen synthesis and signaling in the brains of vertebrates has pleotropic effects ranging from neurogenesis to modulation of behaviors. The majority of studies on brain-derived estrogens focus on males, but estrogenic signaling in females likely plays important roles in regulation of reproductive cycling and social behaviors. We used females of the mouth brooding African cichlid fish, Astatotilapia burtoni, to test for reproductive state-dependent changes in estrogenic signaling capacity within microdissected brain nuclei that are important for social behaviors. Expression levels of the rate-limiting enzyme aromatase, but not estrogen receptors, measured by qPCR changes across the …

Neural Activation Patterns Associated With Maternal Mouthbrooding And Energetic State In An African Cichlid Fish, Karen P. Maruska, Julie M. Butler, Karen E. Field, Christopher Forester, Ashley Augustus

Faculty Publications

© 2020 IBRO Parental care is widespread in the animal kingdom, but for many species, provisioning energetic resources must be balanced with trade-offs between self-promoting and offspring-promoting behaviors. However, little is known about the neural mechanisms underlying these motivational decisions. Mouthbrooding is an extreme form of parental care most common in fishes that provides an ideal opportunity to examine which brain regions are involved in parenting and energetics. The African cichlid fish Astatotilapia burtoni is a maternal mouthbrooder in which females hold developing young inside their mouths for 2 weeks. This brood care makes feeding impossible, so females undergo obligatory …

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 …

The Hellan-Herrmann-Johnson Method With Curved Elements, Douglas N. Arnold, Shawn W. Walker

Faculty Publications

We study the finite element approximation of the Kirchhoff plate equation on domains with curved boundaries using the Hellan-Herrmann-Johnson (HHJ) method. We prove optimal convergence on domains with piecewise C^k+1 boundary for k ≥ 1 when using a parametric (curved) HHJ space. Computational results are given that demonstrate optimal convergence and how convergence degrades when curved triangles of insufficient polynomial degree are used. Moreover, we show that the lowest order HHJ method on a polygonal approximation of the disk does not succumb to the classic Babuška paradox, highlighting the geometrically nonconforming aspect of the HHJ method.

Dynamics Of Pdms- G-Pdms Bottlebrush Polymers By Broadband Dielectric Spectroscopy, Bruno Jakobi, Karin J. Bichler, Anna Sokolova, Gerald J. Schneider

Faculty Publications

Copyright © 2020 American Chemical Society. Poly(dimethylsiloxane) (PDMS)-based bottlebrush polymers, PDMS-g-PDMS, have been synthesized by anionic polymerization in combination with a condensation-based grafting reaction. Bottlebrush polymers show intriguing features, e.g., extremely low viscosities. Hereby, studies of their dynamics are rare. Therefore, we focus on the segmental relaxation by broadband dielectric spectroscopy. An increasing cross-sectional radius proportional to the increasing side chain length has been observed by small-angle neutron scattering over three samples. A comparison of the segmental relaxation times of the bottlebrushes with the respective linear chains reveals slower dynamics in the former. For longer chains, this effect vanishes.

Almost Medium-Free Measurement Of The Hoyle State Direct-Decay Component With A Tpc, J. Bishop, G. V. Rogachev, S. Ahn, E. Aboud, M. Barbui, A. Bosh, C. Hunt, H. Jayatissa, E. Koshchiy, R. Malecek, S. T. Marley, E. C. Pollacco, C. D. Pruitt, B. T. Roeder, A. Saastamoinen, L. G. Sobotka, S. Upadhyayula

Faculty Publications

Background: The structure of the Hoyle state, a highly α-clustered state at 7.65 MeV in C12, has long been the subject of debate. Understanding if the system comprises of three weakly interacting α particles in the 0s orbital, known as an α-condensate state, is possible by studying the decay branches of the Hoyle state. Purpose: The direct decay of the Hoyle state into three α particles, rather than through the Be8 ground state, can be identified by studying the energy partition of the three α particles arising from the decay. This paper provides details on the breakup mechanism of the …

Clustering And Α -Capture Reaction Rate From Ab Initio Symmetry-Adapted Descriptions Of Ne 20, A. C. Dreyfuss, K. D. Launey, J. E. Escher, G. H. Sargsyan, R. B. Baker, T. Dytrych, J. P. Draayer

Faculty Publications

We introduce a new framework for studying clustering and for calculating α partial widths using ab initio wave functions. We demonstrate the formalism for Ne20, by calculating the overlap between the O16+α cluster configuration and states in Ne20 computed in the abinitio symmetry-adapted no-core shell model. We present spectroscopic amplitudes and spectroscopic factors, and compare those to no-core symplectic shell-model results in larger model spaces, to gain insight into the underlying physics that drives α clustering. Specifically, we report on the α partial width of the lowest 1- resonance in Ne20, which is found to be in good agreement with …

Higher Csf Strem2 Attenuates Apoe4-Related Risk For Cognitive Decline And Neurodegeneration, Nicolai Franzmeier, M. Suárez-Calvet, Lukas Frontzkowski, Annah Moore, Timothy J. Hohman, Estrella Morenas-Rodriguez, Brigitte Nuscher, Leslie Shaw, John Q. Trojanowski, Martin Dichgans, Gernot Kleinberger, Christian Haass, Michael Ewers, Michael Weiner, Paul Aisen, Gerald Novak, Robert C. Green, Tom Montine, Ronald Petersen, Anthony Gamst, Ronald G. Thomas, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Laurel Beckett, Danielle Harvey, John Kornak, Clifford R. Jack, Anders Dale, Matthew Bernstein, Joel Felmlee, Nick Fox, Paul Thompson

Clinical Research Faculty Publications

Background: The Apolipoprotein E ϵ4 allele (i.e. ApoE4) is the strongest genetic risk factor for sporadic Alzheimer's disease (AD). TREM2 (i.e. Triggering receptor expressed on myeloid cells 2) is a microglial transmembrane protein brain that plays a central role in microglia activation in response to AD brain pathologies. Whether higher TREM2-related microglia activity modulates the risk to develop clinical AD is an open question. Thus, the aim of the current study was to assess whether higher sTREM2 attenuates the effects of ApoE4-effects on future cognitive decline and neurodegeneration. Methods: We included 708 subjects ranging from cognitively normal (CN, n = …

Shelf-Stable Sustainable Shrimp Thermally Processed With Reciprocal Agitation, William R. Dixon, Evelyn G. Watts, John A. King, Xing Fu, Louise Wicker

Faculty Publications

Shelf-stable, ready-to-eat shrimp offer a convenient, portion-controlled option for a highly desirable seafood commodity. The perishability of shrimp requires tight cold-temperature control during distribution and handling. Thermal processing of shrimp was evaluated in a multimode retort with automated control of come-up, heat, and cool times and with addition of high-speed reciprocal agitation. Reciprocal agitation was compared with static retort for thermal process and quality parameters, including cook time, process time to achieve target lethality (F0), cook yield, texture, and appearance of shelf-stable shrimp. Total retort thermal processing times decreased from 30 min at 0 shakes per minute (SPM) to 17.1 …

A Reinforcement Learning Control Approach For Underwater Manipulation Under Position And Torque Constraints, Ignacio Carlucho, Mariano De Paula, Corina Barbalata, Gerardo G. Acosta

Faculty Publications

In marine operations underwater manipulators play a primordial role. However, due to uncertainties in the dynamic model and disturbances caused by the environment, low-level control methods require great capabilities to adapt to change. Furthermore, under position and torque constraints the requirements for the control system are greatly increased. Reinforcement learning is a data driven control technique that can learn complex control policies without the need of a model. The learning capabilities of these type of agents allow for great adaptability to changes in the operative conditions. In this article we present a novel reinforcement learning low-level controller for the position …

New Transitions And Levels For Tb 163 Obtained From Β -Decay Studies, C. J. Zachary, E. Wang, N. T. Brewer, J. C. Batchelder, J. H. Hamilton, J. M. Eldridge, B. M. Musangu, A. V. Ramayya, C. J. Gross, K. P. Rykaczewski, R. Grzywacz, A. C. Dai, F. R. Xu, M. Madurga, D. Miller, D. W. Stracener, C. Jost, E. F. Zganjar, J. A. Winger, M. Karny, S. V. Paulauskas, S. H. Liu, M. Wolińska-Cichocka, S. W. Padgett, A. J. Mendez, K. Miernik, A. Fijałkowska, S. V. Ilyushkin

Faculty Publications

Transitions in Tb163 following β decay of Gd163 were obtained as part of investigations of γ rays emitted following Eu163β decay to Gd163. Detailed analysis of the low-energy structure of Tb163 has been carried out with these data to expand previous β-decay studies and reactions studies of levels in Tb163. Data were collected at the LeRIBSS station of the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory with an array of four Clover HPGe detectors for γ rays and two plastic scintillators for β detection. The γ rays were identified as belonging to Gd163 and Tb163 via mass …