Digital Commons Network^™

Effect Of Heat Treatments On Pore Morphology And Microstructure Of Laser Additive Manufactured Parts, Bin Zhang, Wen Jin Meng, Shuai Shao, Nam Phan, Nima Shamsaei

Faculty Publications

The slit-shaped, lack-of-fusion pores (LFPs) persistent in the additively manufactured (AM) metals are detrimental to their fatigue resistance due to the associated stress concentrations at the edges. Postbuild treatments, such as hot isostatic pressing (HIP), are routinely used to eliminate pores resulting in, however, inconsistent improvements in fatigue performance. This work critically examines the effectiveness of HIP to eliminate such pores in AM Ti-6Al-4V. In addition, conventional heat treatment (HT) is proposed as a candidate remedial process to alleviate the harmful effects of the LFPs. Specifically, the spheroidization effect of HT on the sharp edges of the LFPs is investigated. …

3d Macroporous Zinc Compound/Silicone Hybrid Foams For Amperometric Sensing Of Glucose Oxidase, Ye Wu, Hao Fu, Weiwei Xie, Yingcheng Lin, Orhan Kizilkaya, Jian Xu

Faculty Publications

A 3D porous matrix makes an intriguing sensing platform, which can integrate functional guest molecules. Here, the first demonstration of a zinc compound/silicone hybrid foam is reported for amperometric sensing of glucose oxidase. The silicone foam is fabricated by a self-developed solid-filling-melting method. Two zinc-based polymers, Zn-Compound-1 and Zn-Compound-2, are synthesized. Zn-Compound-1 and Zn-Compound-2 are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, and X-ray absorption nearedge structure spectroscopy of carbon K-edge, oxygen K-edge, and zinc L-edge. Effective amperometric sensing of glucose oxidase is achieved by introducing Zn-Compound-1 or Zn-Compound-2 into the silicone foam, i.e., an …

Constrained Vcg Auction With Multi-Level Channel Valuations For Spatial Spectrum Reuse In Non-Symmetric Networks, Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun

Faculty Publications

Spatial spectrum reuse enables better utilization of limited spectral resources to achieve higher system throughput. However, improving the system throughput or spectrum efficiency does not necessarily translate to the satisfaction of more secondary users (SUs) according to their demands. To improve user satisfaction, user characteristics involving the supply and demand relationship need to be considered and thus enable heterogeneous channel valuations in spatial spectrum reuse. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize user satisfaction in consideration of multi-level flexible channel valuations of the SUs. Specifically, we introduce a Vickrey-Clarke-Groves (VCG) auction, in which …

Quantum Oscillations And A Nontrivial Berry Phase In The Noncentrosymmetric Topological Superconductor Candidate Bipd, Mojammel A. Khan, D. E. Graf, I. Vekhter, D. A. Browne, J. F. Ditusa, W. Adam Phelan, D. P. Young

Faculty Publications

We report the measurements of de Haas-van Alphen (dHvA) oscillations in the noncentrosymmetric superconductor BiPd. Several pieces of a complex multisheet Fermi surface are identified, including a small pocket (α∼40 T) which is three dimensional and anisotropic. From the temperature dependence of the amplitude of the oscillations, the cyclotron effective mass is (0.18±0.02) me. Further analysis revealed a nontrivial π-Berry phase is associated with the 40 T pocket, which strongly supports the presence of topological states in bulk BiPd.

Unpinning The Skyrmion Lattice In Mnsi: Effect Of Substitutional Disorder, C. Dhital, L. Debeer-Schmitt, D. P. Young, J. F. Ditusa

Faculty Publications

By employing magnetization and small angle neutron scattering measurements, we have investigated the behavior of the skyrmion lattice (SKL) and the helical order in MnSi0.992Ga0.008 Our results indicate that the order of the SKL is sensitive to the orientation of an applied magnetic field with respect to the crystal lattice and to variations in the sequence of small temperature and applied magnetic field changes. The disorder caused by the substitution of the heavier element Ga for Si is sufficient to reduce the pinning of the SKL to the underlying crystalline lattice, reducing the propensity for the SKL to be aligned …

Conditional Knock-Out Of Mglur5 From Astrocytes During Epilepsy Development Impairs High-Frequency Glutamate Uptake, Anthony D. Umpierre, Peter J. West, John A. White, Karen S. Wilcox

Faculty Publications

No abstract provided.

Impact Of Psychological And Physical Stressors On The Exercise-Induced Immune Response In Collegiate Swimmers, Connor Alexander Kuremsky

LSU Master's Theses

Evidence suggests high-intensity exercise training increases incidence of upper respiratory infection in young-adult athletes (Spence et al. 2007). Collegiate athletes experience chronic stress, which has been shown to result in increased proportions of late-differentiated CD8+ T-cells of a dysfunctional phenotype (Bosch et al. 2009). However, many studies fail to consider possible moderators such as psychological stress and cytomegalovirus (CMV) infection. Purpose: To examine the impact of psychological stress, CMV infection, and exercise on proportions of early- and late-differentiated CD4+ and CD8+ T-cells in collegiate swimmers over a 7-month training period. Methods: Data were collected from NCAA …

Short Communication: The Topographic Analysis Kit (Tak) For Topotoolbox, Adam M. Fortes

Faculty Publications

Quantitative analysis of digital topographic data is an increasingly important part of many studies in the geosciences. Initially, performing these analyses was a niche endeavor, requiring detailed domain knowledge and programming skills, but increasingly broad, flexible, open-source code bases have been developed to increasingly democratize topographic analysis. However, many of these analyses still require specific computing environments and/or moderate levels of knowledge of both the relevant programming language and the correct way to take these fundamental building blocks and conduct an efficient and effective topographic analysis. To partially address this, we have written the Topographic Analysis Kit (TAK), which leverages …

Reduced Order Finite Time Observers For Time-Varying Nonlinear Systems, Frederic Mazenc, Saeed Ahmed, Michael Malisoff

Faculty Publications

We build reduced order finite time observers for a large class of nonlinear time-varying continuous-time systems. We illustrate our results using a tracking problem for nonholonomic systems in chained form.

Nitrogen Content In The Earth's Outer Core, Suraj K. Bajgain, Mainak Mookherjee, Rajdeep Dasgupta, Dipta B. Ghosh, Bijaya B. Karki

Faculty Publications

Using first principles molecular dynamic simulations, we explore the effects of nitrogen (N) on the density and sound velocity of liquid iron and evaluate its potential as a light element in the Earth's outer core. Our results suggest that Fe-N melt cannot simultaneously explain the density and seismic velocity of the Earth's outer core. Although ~2.0 wt.% N can explain the bulk sound velocity of the outer core, such N content only lowers the density of liquid Fe by ~3%. Matching both the velocity and density by the other light elements limits the N in the core to ≪2.0 wt.%. …

Quantification Of Swell Energy And Its Impact On Wetlands In A Deltaic Estuary, Thomas Everett, Qin Chen, Arash Karimpour, Robert Twilley

Faculty Publications

The extensive coastal wetlands in Mississippi River Delta represent the seventh largest deltaic floodplain in the world, contributing to many services that sustain the economies of the region. Subsidence, sea level rise, saltwater intrusion, wave action from storms, and sediment depletion have contributed to chronic wetland losses, converting vegetated lands into open waters and increasing wind fetch. Among these factors listed, wave energy plays the largest role in marsh edge erosion in an open bay environment. Degrading barrier islands along the shoreline of this delta allow swell energy to enter protected bay areas, contributing to marsh edge erosion. Locally generated …

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m³ (142 ft³) of marsh soil and 3.88 m³ (137 ft³) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These …

Diy In Early Live Electroacoustic Music: John Cage, Gordon Mumma, David Tudor, And The Migration Of Live Electronics From The Studio To Performance, Lindsey Elizabeth Hartman

LSU Doctoral Dissertations

This research examines early live electronic works by Gordon Mumma, David Tudor, and John Cage—three influential American experimental music composers who designed, built, and recontextualized electronics for live performance—and the Do-It-Yourself (DIY) aesthetic embodied by their instruments and the compositions written for them. This dissertation serves as a presentation of original research into the earliest composers of live electronic works and the necessary DIY approach used in building independent systems. Previous research on the DIY perspectives in music often touch on the grass-roots nature of contemporary electroacoustic systems but there is not yet research specific to the DIY approach taken …

Etoxpred: A Machine Learning-Based Approach To Estimate The Toxicity Of Drug Candidates 11 Medical And Health Sciences 1115 Pharmacology And Pharmaceutical Sciences 03 Chemical Sciences 0305 Organic Chemistry 03 Chemical Sciences 0304 Medicinal And Biomolecular Chemistry, Limeng Pu, Misagh Naderi, Tairan Liu, Hsiao Chun Wu, Supratik Mukhopadhyay, Michal Brylinski

Faculty Publications

© 2019 The Author(s). Background: The efficiency of drug development defined as a number of successfully launched new pharmaceuticals normalized by financial investments has significantly declined. Nonetheless, recent advances in high-throughput experimental techniques and computational modeling promise reductions in the costs and development times required to bring new drugs to market. The prediction of toxicity of drug candidates is one of the important components of modern drug discovery. Results: In this work, we describe eToxPred, a new approach to reliably estimate the toxicity and synthetic accessibility of small organic compounds. eToxPred employs machine learning algorithms trained on molecular fingerprints to …

Consistify: Preserving Correctness And Sla Under Weak Consistency, Subhajit Sidhanta, Supratik Mukhopadhyay, Wojciech Golab

Faculty Publications

While executing a client application, comprising a sequence of one or more storage operations (read, write, etc.), replicated datastores provide the option of tuning per-operation client-centric consistency settings, Weaker consistency settings allow client applications to execute with lower observed latency due to less coordination among the replica, improving throughput. To enable a client application running on a geo-replicated datastore to meet stringent SLA (Service Level Agreement) deadlines, i.e., latency thresholds provided in the SLA, users apply weak client-centric consistency settings. Strong consistency settings may result in higher latency due to coordination among greater number of replicas. However, since a weak …

A Critical Edition Of The Bachianas Brasileiras Nº2 For Piano And Cello By Heitor Villa-Lobos, Henrique Borges Gomes

LSU Doctoral Dissertations

The Brazilian composer Heitor Villa-Lobos (1887-1959) is one of the most prominent names in Twentieth century music. His compositional scope encompasses languages that often combine national elements of Brazilian music with traditions of European music. Villa-Lobos’s Bachianas Brasileiras is one of the most representative works that reflect the dialogue of those distinct worlds. With this series of distinct pieces, Villa-Lobos aimed to achieve musical universality through incorporating elements of Bach’s music with that of his own, which was already permeated by Brazilian popular traditions.

This research focusses on the four movements of the “reduced” version of the Bachianas Brasileiras no.2 …

Photo-Induced Remote C-H Functionalization And New Thioglycoside Donor Development For O-Glycosylation, Shaofu Du

LSU Doctoral Dissertations

This dissertation focuses on the method development of C-H functionalization using photo-redox catalysis and the synthesis of new thioglycoside donors towards O-glycosylation. Chapter 1 describes the remote Csp³-H functionalization using photo-redox catalysis. The site-selective and high-yielding conversion of unreactive aliphatic C-H bonds has been a challenge for organic chemists for many years. In this work, inert C-H bonds were successfully converted to more useful C-C, C-N, and C-O bonds via hydrogen atom transfer (HAT), radical translocation and polar crossover. This mechanistic manifold was enacted by visible-light irradiation of o-diazoniaphenyl alkyl sulfones in the presence of Ru(bpy) …

The Influence Of Selected Factors On The Perceived Work Readiness Of Undergraduate Program Completers At A Research University, Karen Lynne Goodridge

LSU Doctoral Dissertations

The primary purpose of this study was to determine the influence of selected personal, academic, and employment characteristics on the perceived work readiness of undergraduate program completers at a research university located in the Southern Region of the United States. The target population was undergraduate program completers at research universities in the United States. The accessible population was undergraduate program completers at one selected research university (RU/VH) located in the Southern Region of the United States. The sample comprised 100% of the defined accessible population who completed a graduating student survey administered by the Office of Career Services (OCS) at …

The Tensile Root Strength Of Spartina Patens Varies With Soil Texture And Atrazine Concentration, L O. Hollis, R. Eugene Turner

Faculty Publications

The widely used agricultural herbicide atrazine enters wetlands and may potentially affect wetland plants that provide critical reinforcement of soil strength and contribute to ecosystem stability in ways that may vary among soil types. We conducted greenhouse experiments using four levels of atrazine doses and three different soil textures to test for differences between control and experimental treatments and interactive effects of soil texture and atrazine exposure by using the tensile root strength of the coastal wetland emergent macrophyte Spartina patens as the response variable. The tensile root strength of S. patens was not affected after 50days of atrazine exposure …

Feedback Of Coastal Marshes To Climate Change: Long-Term Phenological Shifts, Y Mo, M S. Kearney, R. Eugene Turner

Faculty Publications

Coastal marshes are important carbon sinks facing serious threats from climatic stressors. Current research reveals that the growth of individual marsh plants is susceptible to a changing climate, but the responses of different marsh systems at a landscape scale are less clear. Here, we document the multi-decadal changes in the phenology and the area of the extensive coastal marshes in Louisiana, USA, a representative of coastal ecosystems around the world that currently experiencing sea-level rise, temperature warming, and atmospheric CO2 increase. The phenological records are constructed using the longest continuous satellite-based record of the Earth's ecosystems, the Landsat data, and …

Resuscitation Of Microalgae From Mississippi River Plume Sediments, Chase C. Chaplin, Marnie Tabor, Israel A. Marquez, Kanchan Maiti, Jeffrey W. Krause

Faculty Publications

No abstract provided.

Reduced Caco 3 Flux To The Seafloor And Weaker Bottom Current Speeds Curtail Benthic Caco 3 Dissolution Over The 21st Century, Olivier Sulpis, Carolina O. Dufour, David S. Trossman, Andrea J. Fassbender, Brian K. Arbic, Bernard P. Boudreau, John P. Dunne, Alfonso Mucci

Faculty Publications

No abstract provided.

Gumbo Yearbook, Class Of 2019, Louisiana State University And Agricultural And Mechanical College

Gumbo Yearbook

The Gumbo yearbook chronicles the entire academic year at LSU. In words and especially photos, the Gumbo shows the people, places, and events that make each year unique. In addition to formal portraits of schools and departments, the book contains hundreds of snapshots of students with their friends and dozens of pages showcasing organizations.

Two Isomers Of [1-Benzyl-4-(Pyridin-2-Yl-Jn)-1h-1,2,3-Triazole-Jn3]Dichloridobis(Dimethyl Sulfoxide-Js)Ruthenium(Ii), Fatemeh Khamespanah, Andrew W. Maverick

Faculty Publications

© 2019 International Union of Crystallography. All rights reserved. The structures of two isomers of the title compound, [RuCl2(C14H12N4)-(C2H6OS)2], 2 and 3, are reported. Isomers 2 and 3 are produced by reaction of the pyridyltriazole ligand 1-benzyl-4-(pyridin-2-yl)-1H-1,2,3-triazole (bpt) (1) with fac-[RuCl2(DMSO-S)3(DMSO-O)]. Reaction in acetone produces ca 95% 2, which is the OC-6-14 isomer, with cis DMSO and trans chlorido ligands, and 5% 3 (the OC-6-32 isomer, with cis DMSO and cis chlorido ligands, and the pyridyl moiety of bpt trans to DMSO). Reaction in refluxing toluene initially forms 2, which slowly isomerizes to 3.

Growth And Development Symposium: Stem And Progenitor Cells In Animal Growth: The Regulation Of Beef Quality By Resident Progenitor Cells, Xing Fu, Chaoyang Li, Qianglin Liu, Kenneth W. Mcmillin

Faculty Publications

© The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. The intramuscular adipose tissue deposition in the skeletal muscle of beef cattle is a highly desired trait essential for high-quality beef. In contrast, the excessive accumulation of crosslinked collagen in intramuscular connective tissue contributes to beef toughness. Recent studies revealed that adipose tissue and connective tissue share an embryonic origin in mice and may be derived from a common immediate bipotent precursor in mice and humans. Having the same linkages in the development of adipose tissue and connective tissue …

Church In The Wild: Evangelicals In Antebellum America, Spencer W. Mcbride

Civil War Book Review

Scholars have written extensively about this historic development in American religious culture. In Church in the Wild, Brett Malcolm Grainger builds upon that body of scholarship and offers a fresh view of the ways that praying in the woods altered evangelical Christianity in the United States and Americans’ understandings of the natural world. “Evangelicals participated in the most popular movement of nature spiritualism in nineteenth-century America,” Grainger argues, “a movement based upon the conviction that the natural world was enlivened by Christ, the alpha and omega of all created things” (p. 3).

Mitofusin 2 Plays A Role In Oocyte And Follicle Development, And Is Required To Maintain Ovarian Follicular Reserve During Reproductive Aging, Man Zhang, Muhammed Burak Bener, Zongliang Jiang, Tianren Wang, Ecem Esencan, Richard Scott, Tamas Horvath, Emre Seli

Faculty Publications

© Zhang et al. Mitochondria change their shape through fusion and fission in order to adapt to their metabolic milieu. Mitofusin-2 (MFN2) is a key regulatory protein in this process, mediating mitochondrial fusion and interaction with endoplasmic reticulum. Targeted deletion of Mfn2 in oocytes resulted in mitochondrial dysfunction and female subfertility associated with impaired oocyte maturation and follicle development. Oocytes lacking MFN2 showed shortened telomeres and increased apoptosis, resulting in compromised oocyte quality and accelerated follicular depletion, consistent with a reproductive aging phenotype.

Dosage Compensation And Gene Expression Of The X Chromosome In Sheep, Jingyue Duan, Kaleigh Flock, Nathanial Jue, Mingyuan Zhang, Amanda Jones, Sahar Al Seesi, Ion Mandoiu, Sambhu Pillai, Maria Hoffman, Rachel O'Neill, Steven Zinn, Kristen Govoni, Sarah Reed, Hesheng Jiang, Zongliang Jiang, Xiuchun Tian

Faculty Publications

© 2019 by the Genetics Society of America. Ohno's hypothesis predicts that the expression of the single X chromosome in males needs compensatory upregulation to balance its dosage with that of the diploid autosomes. Additionally, X chromosome inactivation ensures that quadruple expression of the two X chromosomes is avoided in females. These mechanisms have been actively studied in mice and humans but lag behind in domestic species. Using RNA sequencing data, we analyzed the X chromosome upregulation in sheep fetal tissues from day 135 of gestation under control, over or restricted maternal diets (100%, 140% and 60% of National Research …

A Highly Contiguous Reference Genome For Northern Bobwhite (Colinus Virginianus), Jessie F. Salter, Oscar Johnson, Norman J. Stafford, William F. Herrin, Darren Schilling, Cody Cedotal, Robb T. Brumfield, Brant C. Faircloth

Faculty Publications

Copyright © 2019 Salter et al. Northern bobwhites (Colinus virginianus) are small quails in the New World Quail family (Odontophoridae) and are one of the most phenotypically diverse avian species. Despite extensive research on bobwhite ecology, genomic studies investigating the evolution of phenotypic diversity in this species are lacking. Here, we present a new, highly contiguous assembly for bobwhites using tissue samples from a vouchered, wild, female bird collected in Louisiana. By performing a de novo assembly and scaffolding the assembly with Dovetail Chicago and HiC libraries and the HiRise pipeline, we produced an 866.8 Mb assembly including 1,512 scaffolds …

Quantum Channel Capacities Per Unit Cost, Dawei Ding, Dmitri S. Pavlichin, Mark M. Wilde

Faculty Publications

Communication over a noisy channel is often conducted in a setting in which different input symbols to the channel incur a certain cost. For example, for bosonic quantum channels, the cost associated with an input state is the number of photons, which is proportional to the energy consumed. In such a setting, it is often useful to know the maximum amount of information that can be reliably transmitted per cost incurred. This is known as the capacity per unit cost. In this paper, we generalize the capacity per unit cost to various communication tasks involving a quantum channel, such as …