Digital Commons Network^™

Cationic Cobalt (Ii) Hydroformylation, Drew Michael Hood

LSU Doctoral Dissertations

While investigating a bimetallic cobalt hydroformylation catalyst a new class of monometallic cationic cobalt (II) hydroformylation catalyst were discovered. These newly discovered catalyst proved to be very unique with high hydroformylation activity under mild conditions. The pre-catalyst were characterized using various methods including NMR, EPR, MS, and X-ray crystallography. Similarly the active catalyst was also investigated using NMR, EPR, FTIR, and X-ray crystallography. Various catalyst modifications were investigated for their effects on hydroformylation activity. Likewise various reaction parameters were probed to determine their effect on hydroformylation activity. Finally the best cationic cobalt (II) catalyst were directly compared to industry standards …

Understanding Host-Fungus Interactions Between Soybean And Phakopsora Pachyrhizi To Enhance Soybean Resistance To Rust Disease, Dongfang Hu

LSU Doctoral Dissertations

Asian soybean rust (ASR) caused by Phakopsora pachyrhizi was first reported in Japan in 1902. In 2004, Asian soybean rust was first reported in Louisiana and other Southeastern US states. It is one of the most important soybean diseases worldwide. Even though fungicide application can offer some protection and prevent severe yield losses caused by ASR if applied promptly, it is not a viable option as a long-term disease control measure because it increases the growers’ operation costs and the risk of environmental pollution. In addition, it also increases the chances of developing fungicide resistance within a pathogen population. The …

Identification And Characterization Of Novel Transporters Involved In The Co2 Concentrating Mechanism Of Chlamydomonas Reinhardtii, Ananya Mukherjee

LSU Doctoral Dissertations

The green alga Chlamydomonas reinhardtii possesses a CO₂ concentrating mechanism (CCM) which helps in successful acclimation to low CO₂ conditions. One of the main aspects of the CCM is bringing in inorganic carbon (Ci) into the cell as bicarbonate using Ci transporters. Current models of the CCM postulate that a series of ion transporters bring HCO₃^- from outside the cell to the thylakoid lumen where the carbonic anhydrase, CAH3, dehydrates accumulated HCO₃^- to CO₂, raising the CO₂ concentration for Rubisco. Previously, HCO₃^- transporters have been identified at both the …

Improving Coupled Enzyme Assays With Capillary Electrophoresis, Thu Hoai Nguyen

LSU Doctoral Dissertations

The goal of this project is to address limitations of coupled enzyme assays using capillary electrophoresis (CE). In some enzyme assays, it is ineffective to directly detect products and substrates spectroscopically (absorption or fluorescence). Coupling the enzyme-catalyzed reaction of interest with another enzyme-catalyzed reaction allows for indirect detection of product formation or substrate depletion for the target enzyme. While conventional coupled enzyme assays are facile for kinetic measurements, they can be problematic for inhibition screening due to spectral and inhibitor interferences. To address these limitations of coupled assays, CE has been used to develop enzyme assays for acetyl-coenzyme A carboxylase …

An Archive Of Pain: In Queer Suicide's Cultural Wake, Evan Schares

LSU Doctoral Dissertations

In this dissertation, I argue that queer death is a chief site of political struggle over gender, race, and sexuality in contemporary culture. I consider myriad archives in the aftermath of three queer suicides, an aggregate of discourses I call cultural wakes, to examine how white affective investments circulate around the forces of racism, sexism, and citizenship. I place in situ the trauma of queer pain and loss against the global backdrop of public emotionality.

From Rationality To Relationality: Teacher-Student Relationship As Unknowing, Shaofei Han

LSU Doctoral Dissertations

This dissertation reimagines the teacher-student relationship through a philosophical approach that draws on Laozi, Karen Barad, Deleuze & Guattari, and Emmanuel Levinas. The teacher-student relationship is normally considered a relationship of the knower (teacher) and the unknower (student) based on the modern western tradition of episteme. This dissertation interrogates the modern binary of the teacher/student, subject/object relationship by bringing ontology and ethics into educational discourse. The problematic practices of modern schooling include the reduction of teaching to knowledge transmission, and the rigid dichotomy of a subject/object relation between teacher and student. Following a Taoist Way of philosophical thinking, this work …

Mechanisms To Regulate Genes Encoding Clinically Relevant Multidrug Transporters At The Crossroads Of Antibiotic Resistance And Oxidative Stress Detection, Afsana Sabrin

LSU Doctoral Dissertations

Multiple Antibiotic Resistance Regulators (MarRs) are DNA binding proteins involved in bacterial survival and pathogenesis. My PhD dissertation focuses on a MarR homolog, OstR, which regulates genes encoding major multidrug transporters, a resistance-nodulation-division (RND) and an E. coli multidrug resistance B (EmrB) efflux pump homolog in Burkholderia thailandensis. The ostR gene is divergently oriented from genes encoding a hypothetical protein (Hyp) and an RND transporter and adjacent to a gene encoding an EmrB transporter. OstR binds to the promoters of each gene (K_d = 64.9 ± 8.0 nM, K_d = 126.1 ± 10.9 nM and K …

Can Assisted Reproductive Technologies Help Conserve 300 Million Years Of Evolution? A First Attempt At Developing These Technologies For Male Reptiles, Sean M. Perry

LSU Doctoral Dissertations

Biodiversity loss is the most critical environmental problem threatening ecosystem, animal, and human health today. Increases in extinction rates have been observed over the past 50 years, with reptile losses occurring twelve times faster than traditional extinction rates. This demonstrated biodiversity loss is secondary to climate change, habitat destruction, infectious disease, invasive species, poaching, and unsustainable trade. Approximately 20% of all reptiles are threatened with extinction and population declines are approaching rates similar to the current amphibian extinction crisis. Preventing the extinction of reptiles will require humans to acknowledge these losses and develop plans to preserve these evolutionary sentinel species. …

Phylogeny And Evolution Of Swallows (Hirundinidae) With A Transcriptomic Perspective On Seasonal Migration, Clare Elisabeth Brown

LSU Doctoral Dissertations

Evolutionary biology seeks to understand the forces that have generated and shaped patterns of diversity. In this dissertation, I investigated phylogenetic relationships and the evolution of three traits—migration, nest-type, and geographic distribution—in the swallow family (Hirundinidae), a globally distributed group of about 85 species of aerial insectivorous birds. I first applied a dataset of several thousand ultraconserved element (UCE) loci to reconstructing the phylogeny of the New World genus Tachycineta. Three methods of phylogenetic inference produced topologically discordant trees, but post-inference analyses provided evidence that the tree produced by maximum likelihood analysis of a concatenated data matrix is the most …

Population Dynamics And Demographics Of Spotted Seatrout, Cynoscion Nebulosus, Through Spatial Analysis: Towards An Integrative Management Approach, Ashley Melancon Baer

LSU Doctoral Dissertations

Spotted seatrout (Cynoscion nebulosus) is one of the most highly prized sportfish along the Gulf of Mexico coast, particularly in Louisiana. Although spotted seatrout are considered to be well managed and sustainably fished according to the state’s most recent stock assessment, the spatial ecology of this species is largely understudied in Louisiana waters. Acoustic telemetry is an innovative technology that is commonly used to assess the movements and behavior of aquatic species, and can be used as a tool to address the paucity of information on the spatial dynamics of spotted seatrout. The focus of this study was …

"Moving One Seat Over": Division I Women's Basketball Female Assistant Coaches' Views Of Head Coaching, Caitlin Kriesel-Bigler

LSU Master's Theses

Abstract

At the time Title IX passed in 1972, over 90% of women’s athletic teams were coached by women. By 2014, that percentage had dropped to 43%. This study used in-depth interviews with four female Division I assistant basketball coaches with varying years of experience to explore their experiences and attitudes towards becoming head coaches. The interviews revealed five major themes: (a) The Power of Same-Sex Role Models; (b) Gender Differences and Whether They Matter; (c) Title IX Collateral Damage: “It’s Nothing but the Money”; (d) Gender-Related Obstacles; and (e) Preparation for “Moving Over One Seat.” The findings reveal that …

Understanding The Social Relationships Of Youth With Callous-Unemotional Traits Using Peer Nominations, Tatiana M. Matlasz

LSU Master's Theses

The current study investigated the social correlates of conduct problems (CP) and callous-unemotional (CU) traits using peer nominations. Participants (n = 289), drawn from a sample of 3^rd, 6^th, and 8^thgraders (M_age = 11.47 years; SD = 2.26), were asked to identify peers who they believed fit a number of different characteristics, in addition to individuals who they liked most and liked least. We also obtained self-, parent-, and teacher-reports of children’s behaviors. Analyses extracted three primary dimensions from peer nominations, including, indicators of being mean and cold (Mean/Cold), of being aloof and …

Determination Of Conversion Factors For Various Calibration Geometries Using Barium-133 In A Silver Zeolite Cartridge, Amin Hamideh

LSU Master's Theses

Iodine-131 (I-131) is a major fission product among other radionuclides released during a nuclear incident. This radioiodine has a half-life of 8.02 days and the primary organ of uptake through ingestion or inhalation is the thyroid gland. For these reasons, nuclear power plants must routinely monitor I-131 through air sampling. Currently, there are two adsorbing media to collect I-131: activated charcoal and silver zeolite cartridges. Silver zeolite cartridges are generally used during a post nuclear incident due to its affinity for iodine while not adsorbing noble gases such as krypton-85 and xenon-135. After an air sample is taken from a …

Distinct Fractions Of An Artemisia Scoparia Extract Contain Compounds With Novel Adipogenic Bioactivity, Anik Boudreau, Alexander Poulev, David M. Ribnicky, Ilya Raskin, Thirumurugan Rathinasabapathy, Allison J. Richard, Jacqueline M. Stephens

Faculty Publications

© 2019 Boudreau, Poulev, Ribnicky, Raskin, Rathinasabapathy, Richard and Stephens. Adipocytes are important players in metabolic health and disease, and disruption of adipocyte development or function contributes to metabolic dysregulation. Hence, adipocytes are significant targets for therapeutic intervention in obesity and metabolic syndrome. Plants have long been sources for bioactive compounds and drugs. In previous studies, we screened botanical extracts for effects on adipogenesis in vitro and discovered that an ethanolic extract of Artemisia scoparia (SCO) could promote adipocyte differentiation. To follow up on these studies, we have used various separation methods to identify the compound(s) responsible for SCO's adipogenic …

Putting It All Together: Adding Value To The Global Ocean And Climate Observing Systems With Complete Self-Consistent Ocean State And Parameter Estimates, David Trossman

Faculty Publications

No abstract provided.

Evaluating Seasonal Nutrient Fluxes In Emerging And Eroding Wetlands Of The Louisiana Delta Plain, Kiran Upreti

LSU Doctoral Dissertations

Deltaic wetlands can ameliorate high NO₃^- loads via denitrification, a dominant NO₃^- reduction pathway in inland and coastal habitats. Dissimilatory Nitrate Reduction to Ammonia (DNRA), in contrast to denitrification, conserves N within the system and has been found to be favored over denitrification with increase in salinity and temperature. There are no studies in the Louisiana Deltaic plain with simultaneous estimation of denitrification and DNRA. Increased P availability has been shown to increase denitrification so it is essential to understand P biogeochemistry when studying N cycle. Here, we evaluated net denitrification using N₂:Ar and …

Phase Estimation In Linear And Nonlinear Interferometers, Sushovit Adhikari

LSU Doctoral Dissertations

Phase estimation has a wide range of applications. Over the years, several strategies have been studied to improve precision in phase estimation. These strategies include using exotic quantum states to quantum detection schemes. This dissertation summarizes my effort in improving the precision of phase estimation with a linear and nonlinear interferometer.

Chapter 1 introduces quantum optics and quantum metrology. I introduce all relevant quantum states of light used. We also look into tools and terminologies of quantum metrology such as Fisher information, shot-noise limit, Heisenberg limit, etc., along with examples of phase estimation with a Mach-Zehnder interferometer.

In Chapter 2, …

Cross-Shelf Habitat Shifts By Red Snapper (Lutjanus Campechanus) In The Gulf Of Mexico, Michael A. Dance, Jay R. Rooker

Faculty Publications

Habitat shifts that occur during the life cycles of marine fishes influence population connectivity and structure. A generalized additive modeling approach was used to characterize relationships between environmental variables and the relative abundance of red snapper Lutjanus campechanus over unconsolidated substrate on the continental shelf (< 150 m) of the U.S. Gulf of Mexico (GoM) at three different life stages: juvenile (age-0, < 125 mm FL), sub-adult (age-1-2, 125–300 mm FL), and adult (age-2+, >300 mm FL). Fisheries independent data (2008–2014) were used to develop separate models for both the eastern and western GoM, and final models were used to predict the relative availability of suitable habitat for each life stage across the two regions. Predictor variables included in final models varied by age class and region, with …

Marr Family Transcription Factors From Burkholderia Species: Hidden Clues To Control Of Virulence-Associated Genes, Ashish Gupta, Anuja Pande, Afsana Sabrin, Sudarshan S. Thapa, Brennan W. Gioe, Anne Grove

Faculty Publications

Copyright © 2019 American Society for Microbiology. All Rights Reserved. Species within the genus Burkholderia exhibit remarkable phenotypic diversity. Genomic plasticity, including genome reduction and horizontal gene transfer, has been correlated with virulence traits in several species. However, the conservation of virulence genes in species otherwise considered to have limited potential for infection suggests that phenotypic diversity may not be explained solely on the basis of genetic diversity. Instead, differential organization and control of gene regulatory networks may underlie many phenotypic differences. In this review, we evaluate how regulation of gene expression by members of the multiple antibiotic resistance regulator …

Bioassay-Guided Isolation And Structure Elucidation Of Fungicidal And Herbicidal Compounds From Ambrosia Salsola (Asteraceae), Frank R. Fronczek

Faculty Publications

The discovery of potent natural and ecofriendly pesticides is one of the focuses of the agrochemical industry, and plant species are a source of many potentially active compounds. We describe the bioassay-guided isolation of antifungal and phytotoxic compounds from the ethyl acetate extract of Ambrosia salsola twigs and leaves. With this methodology, we isolated and identified twelve compounds (four chalcones, six flavonols and two pseudoguaianolide sesquiterpene lactones). Three new chalcones were elucidated as (S)-beta-Hydroxy-2,3,4,6'-tetrahydroxy-5-methoxydihydrochalcone (salsolol A), (S)-beta-Hydroxy-2',4,4',6'-tetrahydroxy-3-methoxydihydrochalcone (salsolol B), and (R)-alpha, (R)-beta-Dihydroxy-2,3,4,4,6'-pentahydroxydihydrochalcone (salsolol C) together with nine known compounds: balanochalcone, six quercetin derivatives, confertin, and neoambrosin. Chemical structures were determined …

The Aqueous Environment As An Active Participant In The Protein Folding Process, Michal Brylinski

Faculty Publications

Existing computational models applied in the protein structure prediction process do not sufficiently account for the presence of the aqueous solvent. The solvent is usually represented by a predetermined number of H2O molecules in the bounding box which contains the target chain. The fuzzy oil drop (FOD) model, presented in this paper, follows an alternative approach, with the solvent assuming the form of a continuous external hydrophobic force field, with a Gaussian distribution. The effect of this force field is to guide hydrophobic residues towards the center of the protein body, while promoting exposure of hydrophilic residues on its surface. …

Pyrethroid And Organophosphate Pesticide Resistance In Field Populations Of Horn Fly In Brazil, L. G. Brito, F. S. Barbieri, R. B. Rocha, A. P.L. Santos, R. R. Silva, E. S. Ribeiro, F. Guerrero, L. Foil, M. C.S. Oliveira

Faculty Publications

© 2018 The Royal Entomological Society Pesticides are used worldwide to control arthropod parasites in cattle herds. The indiscriminate and/or inappropriate use of pesticides without veterinary guidance is a reality in several countries of South America. Improper pesticide use increases the chances of contamination of food and the environment with chemical pesticides and their metabolites. Reduction of these contamination events is an increasing challenge for those involved in livestock production. The horn fly, Haematobia irritans (Linnaeus) (Diptera: Muscidae), is one of the most economically important parasites affecting cattle herds around the world. As such, horn fly control efforts are often …

Deep-Ultraviolet Laser Ablation Electrospray Ionization Mass Spectrometry, Remilekun O. Lawal, Fabrizio Donnarumma, Kermit K. Murray

Faculty Publications

© 2019 John Wiley & Sons, Ltd. A 193-nm wavelength deep ultraviolet laser was used for ambient laser ablation electrospray ionization mass spectrometry of biological samples. A pulsed ArF excimer laser was used to ablate solid samples, and the resulting plume of the desorbed material merged with charged electrospray droplets to form ions that were detected with a quadrupole time-of-flight mass spectrometer. Solutions containing peptide and protein standards up to 66-kDa molecular weight were deposited on a metal target, dried, and analyzed. No fragmentation was observed from peptides and proteins as well as from the more easily fragmented vitamin B …

Apoptosis Signal-Regulating Kinase-1 Promotes Inflammasome Priming In Macrophages, Camille N. Immanuel, Bin Teng, Brittany Dong, Elizabeth M. Gordon, Joseph A. Kennedy, Charlean Luellen, Andreas Schwingshackl, Stephania A. Cormier, Elizabeth A. Fitzpatrick, Christopher M. Waters

Faculty Publications

© 2019 the American Physiological Society. previously showed that mice deficient in apo-ptosis signal-regulating kinase-1 (ASK1) were partially protected against ventilator-induced lung injury. Because ASK1 can promote both cell death and inflammation, we hypothesized that ASK1 activation regulates inflammasome-mediated inflammation. Mice deficient in ASK1 expression (ASK1 +/+ ) exhibited significantly less inflammation and lung injury (as measured by neutrophil infiltration, IL-6, and IL-1β) in response to treatment with inhaled lipopolysaccharide (LPS) compared with wild-type (WT) mice. To determine whether this proinflammatory response was mediated by ASK1, we investigated inflammasome-mediated responses to LPS in primary macrophages and bone marrow-derived macrophages (BMDMs) …

The Effect Of The Oxford Movement On The Family And Eucharistic Symbolism In Victorian Literature, Elizabeth Vukovics

Honors Capstones

No abstract provided.

The Effects Of Natural Disasters On Subnational Economic Growth In Latin America And The Caribbean, Olevia Sharbaugh

Honors Capstones

No abstract provided.

Magnetic Properties Of Feni3 Nanoparticle Modified Pinus Radiata Wood Nanocomposites, Li Li Wang, Na Li, Tiqi Zhao, Bin Li, Yali Ji

Faculty Publications

Magnetic FeNi3 nanoparticles were synthesized in the internal structure of wood through an in situ fabrication approach. The morphology, crystalline phase and chemical composition of the FeNi3 modified wood was investigated by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) analysis and X-ray photoelectron spectroscopy (XPS). SEM confirmed that the magnetic nanoparticles were densely dispersed in the wood matrix. The magnetic hysteresis loops showed that the magnetism of composites is dependent on the amount of FeNi3 loading. The saturation magnetization of magnetic wood increases from 6.3 to 10.8 emu/g with an …

Rapid Daily Change In Surface Water Pco 2 And Co 2 Evasion: A Case Study In A Subtropical Eutrophic Lake In Southern Usa, Y. Jun Xu, Zhen Xu, Rongjie Yang

Faculty Publications

Evasion of carbon dioxide (CO 2 ) from lakes is a significant component in the continental carbon balance, but most current CO 2 evasion estimates ignore daily CO 2 fluctuations. To test the hypothesis that partial pressure of CO 2 (pCO 2 ) and CO 2 evasion vary throughout a day due to biological processes driven by solar radiation, we conducted in-situ pCO 2 and ambient water measurements over eleven 10-h periods in a subtropical, eutrophic shallow lake from November 2017 to May 2018. In-situ measurements were performed at 7:00, 10:00, 14:00, and 17:00 Central Standard Time of the United …

Applications Of Unmanned Aerial Vehicles To Survey Mesocarnivores, Jacob D. Bushaw, Kevin M. Ringelman, Frank C. Rohwer

Faculty Publications

With the widespread extirpation of top predators over the past two centuries, mesocarnivores play an increasingly important role in structuring terrestrial trophic webs. However, mesocarnivores are difficult to survey at a population level because their widely spaced territories and nocturnal behavior result in low detection probability. Existing field survey techniques such as track plates and motion-sensitive camera traps are time-consuming and expensive, and yet still yield data prone to systematic errors. Unmanned Aerial Vehicles (UAVs) have recently emerged as a new tool for conducting population surveys on a wide variety of wildlife, eclipsing the efficiency and even accuracy of traditional …

Application Of Steam Explosion In Oil Extraction Of Camellia Seed (Camellia Oleifera Abel.) And Evaluation Of Its Physicochemical Properties, Fatty Acid, And Antioxidant Activities, Shanying Zhang, Yong Gui Pan, Lili Zheng, Yang Yang, Xiaoyan Zheng, Binling Ai, Zhimin Xu, Zhanwu Sheng

Faculty Publications

This study evaluated the physicochemical properties of oils extracted from steam-exploded camellia seed (Camellia oleifera Abel.). Steam pressure, resident time, fatty acid composition, total phenolics, tocopherol, squalene, and sterol contents, and volatile compounds were determined. 1 H NMR and FTIR spectra were performed for the structure of camellia seed oil. This study has found the highest yield of oil was 86.56% and was obtained when steam explosion pretreatment was at 1.6 MPa 30 s. Oil extracted by steam explosion pretreatment exhibited favorable physicochemical properties and stronger antioxidant activities compared to untreated oil. The compositions of fatty acid were similar between …