Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Oyster Norovirus Outbreaks Along The U.S. Gulf Coast, Shima Shamkhali Chenar

LSU Doctoral Dissertations

Oyster norovirus outbreaks pose increasing risks to human health and seafood industry worldwide. This study presents an Artificial Intelligence (AI)-based approach to identifying the primary cause of oyster norovirus outbreaks, nowcasting and forecasting the growing risk of oyster norovirus outbreaks in coastal waters. AI models were developed using Artificial Neural Networks (ANNs) and Genetic Programming (GP) methods and time series of epidemiological and environmental data. Input variable selection techniques, including Random Forests (RF) and Forwards Binary Logistic Regression (FBLR), were used to identify the significant model input variables among six independent environmental predictors including water temperature, solar radiation, gage height, …

Incorporation Of Biorationals And Trap Crop For Stink Bug Management In Soybeans, Kukuh Hernowo

LSU Doctoral Dissertations

Stink bugs are one of the most important seed sucking pests impacting soybean production in Louisiana. Exploration of chemicals that exhibit attraction or repellent activities toward this major pest would be beneficial to develop a push-pull strategy against this pest complex. Spinosad and neem are two commercially available natural insecticides that were claimed to have attractant and repellent activities against stink bugs. To test the potential of these chemicals, a series of experiments was conducted to investigate the olfactory, tactile, feeding, and oviposition preference of stink bugs toward different commercial spinosad products and neem. Additionally, two years of field experiments …

Effects Of Soil Silicon Amendment And Nitrogen Levels On Rice Insect Pest Complex, James Michael P. Villegas

LSU Master's Theses

Rice plants are consistently subjected to various pressures by insect pests throughout the growing season. The main insect pest complex reported in Louisiana are the rice water weevil (major early-season insect pest), fall armyworm (sporadic early-season pest), sugarcane borer and rice stalk borer (long- established but sporadic stem boring pests), Mexican rice borer (an invasive stem-boring pest), and rice stink bug (major late-season pest). Soil silicon amendment has been shown to enhance plant resistance against herbivorous pests. Rice is a typical silicon-accumulating graminaceous crop. Field and greenhouse experiments were conducted from 2015 to 2017 to investigate the effects of soil …

Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda

LSU Master's Theses

Aspergillus flavus is a saprophytic ascomycete that can also actively invade the seed of crops and potentially contaminate them with harmful aflatoxins. Management of A. flavus currently relies mostly on biocontrol. However, there is still a lot to learn about its biology and ecology so the current approach can be improved. An A. flavus population survey was undertaken during the fall of 2014 across eight Mississippi River states to determine population diversity and geographic distribution of VCGs. Isolates from corn and soil were also characterized for VCG, sclerotial morphotype, mating type, cyclopiazonic acid, and aflatoxin production in order to determine …

Sweetpotato Virus C And Its Contribution To The Potyvirus Complex In Sweetpotato (Ipomoea Batatas), Favio E. Herrera Eguez

LSU Doctoral Dissertations

In Louisiana, sweetpotato (Ipomoea batatas) is infected in Louisiana by the four ubiquitous potyviruses: Sweetpotato feathery mottle virus (SPFMV), Sweetpotato virus G (SPVG), Sweetpotato virus 2 (SPV2) and the strain of SPFMV previously known as the common strain, recently renamed as Sweetpotato virus C (SPVC). These four viruses belong to the Potyviridae family, with single stranded RNA of ~11kb. In this group of plant viruses, a single polyprotein is coded entirely but later cleaved into ten mature proteins: P1, HC-pro, P3, 6K1, CI, 6K2, NIa-VPg, NIa-Pro Nib and Coat Protein (CP). In sweetpotato potyviruses, two additional open reading …

Nanopatterns Of Zinc Phthalocyanines, Gold Nanoparticles, And Porphyrins Prepared Using Particle Lithography: Characterization Of Patterning Steps With Scanning Probe Microscopy, Ashley Marie Taylor

LSU Doctoral Dissertations

The growth and self-assembly of molecules on surfaces can be directly visualized at the molecular level using studies which combine nanoscale lithography and high-resolution imaging. Nanopatterning provides a unique and practical approach for direct views of surface changes after the key chemical steps of nanopatterning, providing landmarks and baselines for measuring growth in vertical and lateral dimensions. Controlling the arrangement of materials on surfaces at the nanoscale can be achieved using particle lithography. Arrays of well-defined nanostructures can be prepared with reproducible geometries and arrangement. Results for the preparation of nanopatterns produced with particle lithography are presented using high resolution …

Alteration Of Gut Microbiota And Other Properties In Zucker Diabetic Fatty Rats After Antibiotics, Diet And Donor Transplant, Ryan Page

LSU Master's Theses

The compositions of bacterial communities inhabiting the human gut are associated with regulating energy balance, immune response, and neurological functions. Many of these benefits are attributed to byproducts of bacteria that feed on fermentable fibers. Research has shown that obese or lean host can transfer their phenotype to germ-free recipients, via microbiota transplant, without alteration in recipient diet. However, transfer may be attenuated by established microbial communities in conventionally-raised rodents or other species. A knockdown of recipient communities may be required before a transplant for microbiota of donors to populate gut of recipient. This study examined whether obese Zucker Diabetic …

Integrating The Effects Of Salinity On The Physiology Of The Eastern Oyster, Crassostrea Virginica, In The Northern Gulf Of Mexico Through A Dynamic Energy Budget Model, Romain Lavaud, Megan K. La Peyre, Sandra M. Casas, Cédric Bacher, Jérôme F. La Peyre

Faculty Publications

© 2017 We present a Dynamic Energy Budget (DEB) model for the eastern oyster, Crassostrea virginica, which enables the inclusion of salinity as a third environmental variable, on top of the standard foodr and temperature variables. Salinity changes have various effects on the physiology of oysters, potentially altering filtration and respiration rates, and ultimately impacting growth, reproduction and mortality. We tested different hypotheses as to how to include these effects in a DEB model for C. virginica. Specifically, we tested two potential mechanisms to explain changes in oyster shell growth (cm), tissue dry weight (g) and gonad dry weight (g) …

Teachers' Experience Of A Flood In Their School Community: Their Beliefs, Perceptions, And Thoughts About Practice, Caroline Tolentino

LSU Master's Theses

The increasing number of flooding incidences in Louisiana exposes a significant number of children to the possible traumatic effects of this natural disaster. Flooding takes a toll not only on families and children, but on teachers as well. While the effects of other types of disasters on children have been considered in previous studies, research has not thoroughly addressed the effects of flooding on children and on early childhood teachers. Teachers can be very instrumental in helping young children cope and making sure their needs are met after the experience of a traumatic event (Perry & Szalavitz, 2008; Le Brocque, …

Polynomial Regression Analyses Of Parental Desirable Responding, Megan Elizabeth Lilly

LSU Doctoral Dissertations

Child assessments have consistently yielded poor agreement between parent-child self-report measures and considerable research has failed to isolate the underlying source of the discrepancies. Validity testing has successfully been used to differentiate credible from non-credible performance, recognize feigned symptoms, and detect underestimates of ability in adults for decades (Sherman, 2015). Despite these potential benefits, attention to the importance of validity testing in the child assessment literature has been largely neglected. Many psychologists believe children are not capable of feigning or exaggerating their symptoms and lack the underlying motivations and incentives for deception found in adult assessments. Whereas, more research is …

A Role For The Cystic Fibrosis Transmembrane Conductance Regulator In The Nitric Oxide-Dependent Release Of Cl – From Acidic Organelles In Amacrine Cells, Vijai Krishnan, J. Wesley Maddox, Tyler Rodriguez, Evanna Gleason

Faculty Publications

© 2017 the American Physiological Society. γ-Amino butyric acid (GABA) and glycine typically mediate synaptic inhibition because their ligandgated ion channels support the influx of Cl – . However, the electrochemical gradient for Cl – across the postsynaptic plasma membrane determines the voltage response of the postsynaptic cell. Typically, low cytosolic Cl – levels support inhibition, whereas higher levels of cytosolic Cl – can suppress inhibition or promote depolarization. We previously reported that nitric oxide (NO) releases Cl – from acidic organelles and transiently elevates cytosolic Cl – , making the response to GABA and glycine excitatory. In this study, …

Ecology And Biology Of The Redbanded Stink Bug, Piezodorus Guildinii (Westwood) In Louisiana, Anup Bastola

LSU Doctoral Dissertations

The redbanded stink bug, Piezodorus guildinii (Westwood) is an invasive stink bug species that was first documented as a soybean pest in Louisiana during the year 2000. This species continues to expand northward in the MidSouth but information is lacking on its biology and ecology in the U.S. In order to determine P. guildinii’s northern range, studies were designed to investigate the cold tolerance ability of this species. The mean supercooling points of adult P. guildinii ranged from highest -8.3 ± 0.2°C in March to the lowest of -11.0 ± 0.2°C in January. Evaluation of lethal exposure time …

The Role Of Histone H2a.Z Abundance In Modulating Responses To Phosphorus Deficiency In Rice, Sara Zahraeifard

LSU Doctoral Dissertations

Histone variants contribute to chromatin complexity by creating specialized nucleosomes. Here, to investigate the pattern of H2A.Z histone variant distribution and its role in modulating gene expression in rice (Oryza sativa L.), we performed genome-wide profiling of ARP6-dependent H2A.Z deposition in rice seedlings. We demonstrated that under controlled conditions, the majority of H2A.Z deposition is within protein-coding genes (PCG), and the most highly expressed genes are enriched with H2A.Z at their 5’ ends near the transcription start site (TSS), whereas the medium- to low-expressed genes contain H2A.Z across the entire gene. Based on H2A.Z deposition, we categorized genes into …

Coupled Plasmon/Molecule Dynamics Near Core-Shell Nanoparticles: Synthesis, Ultrafast Characterization, And Quantum/Classical Modeling, Holden Tyler Smith

LSU Doctoral Dissertations

In this dissertation, the resonance coupling of chromaphoric dyes adsorbed on the surface of plasmonic nanoparticles (NPs) are investigated using a combined theoretical and experi- mental approach. Colloidal gold, gold-silver core-shell, silver-gold core-shell, and gold-silver- gold core-shell-shell NPs are considered. These NPs are thiolated with mercaptosuccinic acid, and malachite green dyes are adsorbed to the surface of the nanoparticle (NP) via elec- trostatic interactions. Second harmonic generation is used to determine the surface to the isotherm of the molecular dyes to the colloidal nanoparticle surface. Adsorption isotherms show that the SHG intensity increases as the concentration of dye increases, reaching …

Biased Genetic Screen Identifies Novel Genes Involved In Antiviral Defense, Tianyun Long

LSU Doctoral Dissertations

ABSTRACT

RNA interference (RNAi) mediates potent antiviral response across kingdoms. In Caenorhabditis elegans nematodes, antiviral RNAi requires a virus sensor that is conserved in mammals and is amplified by secondary small interfering RNAs that are produced in a Dicer-independent manner.

To better understand worm antiviral RNAi, I carried out a biased genetic screen, aiming to identify novel antiviral RNAi genes. To speed up the gene discovery process, the reporter worms used for this genetic screen were engineered to contain extra copies of 4 known antiviral RNAi genes. Therefore, genetic alleles derived from these 4 genes will be automatically rejected during …

Effect Of Hot Water Conditioning On Microbial Safety And Quality Of In-Shell Pecans, Karuna Kharel

LSU Master's Theses

Hot water conditioning of in-shell pecans is one common practice followed by industries to facilitate shelling. It also acts as a preventive control for potential microbiological contamination that might occur during pre- and post-harvest processes. However, heat treatment may have an effect on the eating quality of nuts. The main objectives of the study were to develop a post-harvest hot water treatment intervention as a kill step to destroy foodborne pathogens on in-shell pecans and evaluate the effect of treatments on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted pecans. The time (1-5 min) and temperature (70, …

The Characterization Of Alpha-Carbonic Anhydrases Through Mutagenesis And Subcellular Localization In Arabidopsis Thaliana, Lance E. Pounds

LSU Master's Theses

Carbonic anhydrases (CAs) are zinc metalloenzymes which catalyze the interconversion of carbon dioxide and bicarbonate. It is hypothesized that CA activity facilitates CO₂ flux in leaf mesophyll cells to maintain optimal rates of photosynthesis or to maintain a pool of inorganic carbon for other metabolic processes. There are three classes of CAs (α, β, and γ) in the model plant Arabidopsis thaliana. The βCAs and γCAs have been well studied, but the αCAs have received relatively little study. There are eight αCA genes in Arabidopsis. This study investigates which αCAs are expressed in shoots, their tissue-specific expression, their …

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …

Heat, Acid And Osmotic Stress Tolerance Of Leuconostoc Mesenteroides As Influenced By Prior Exposure To Various Mild Stress Conditions, Ingrid C. Osorio Rodriguez

LSU Master's Theses

The importance of Leuconostoc mesenteroides is recognized for its contribution to taste in cultured dairy products. It has been cited for its potential role as a probiotic. Consumer demand exists for new dairy products with health benefits. In the manufacture of probiotic-products survival of Leuconostoc mesenteroides would depend on its ability to tolerate challenging processing and storage conditions. Improved viability by prior exposure to mild stresses can increase stress tolerance toward a more severe stress. Furthermore, it can result in cross-protection due to connection of several proteins in response to stresses. Objective was to evaluate the effect of prior …

Virulence Phenotypes Of Rotylenchulus Reniformis: Evaluation Of Host Status Of Cotton And Utility Of Single Nucleotide Polymorphisms (Snps) For Identification, Churamani Khanal

LSU Doctoral Dissertations

Comparative reproduction and pathogenicity of reniform nematode (Rotylenchulus reniformis) populations derived from single-egg masses and collected form West Carroll (WC), Rapides (RAP), Morehouse (MOR), and Tensas (TEN) parishes in Louisiana were evaluated in microplot and greenhouse trials. Data from microplot trials showed significant differences among isolates of reniform nematode in both reproduction and pathogenicity on upland cotton (Gossypium hirsutum) cultivars Phytogen 499 WRF, Deltapine 1133 B2RF, and Phytogen 333 WRF. Across all cotton cultivars, MOR and RAP isolates had the greatest and the least reproduction values of 331.8 and 230.2, respectively. Reduction in plant dry weight, …

Faculty And Staff Knowledge And Perceptions Of African American College Students With Bipolar Disorder Experiences While Attending A Predominantly White Institution, Tiffany Sharell Zachery

LSU Doctoral Dissertations

There are few qualitative studies that document the knowledge and perceptions of faculty and staff about college students that has bipolar disorder. Previous studies of college students with mental health challenges have been found to focus only on a particular race, be outdated, largely quantified (Stein, 2014), or only focused on certain disorders such as: autism spectrum disorder, anxiety, or depression. This qualitative study responded to this gap in the literature by gaining an understanding of university faculty and staff knowledge and perceptions of African American college students with bipolar disorder experiences while attending a Predominantly White Institution, their perceptions …

Pathogenicity And Reproduction Of Isolates Of Reniform Nematode, Rotylenchulus Reniformis, From Louisiana On Soybean And Utility Of Single Nucleotide Polymorphisms To Evaluate Genetic Variability, Herath Mudiyanselage Kularathna

LSU Doctoral Dissertations

Experiments were conducted to evaluate soybean, Glycine max (L.) Merr., responses to indigenous isolates of the reniform nematode (Rotylenchulus reniformis) in Louisiana and to understand the genetic variability of these native isolates. Microplot and greenhouse experiments were conducted to evaluate the comparative reproduction and pathogenicity of single egg-mass populations of R. reniformis isolated from West Carroll (WC), Rapides, Tensas and Morehouse (MOR) parishes of Louisiana. Data from full-season microplot trials, displayed significant differences in reproduction and pathogenicity of the nematode with the commercial soybean cultivars REV 56R63, Pioneer P54T94R, and Dyna-Gro 39RY57. Significantly low population density was observed …

When, How, And Why Did The West Antarctic Ice Sheet Retreat In The Ross Sea Since The Last Glacial Maximum Using Foraminiferal And Porewater Geochemistry, Matthew Decesare

LSU Doctoral Dissertations

The Antarctic Ice Sheets (AIS) began to retreat from their Last Glacial Maximum (LGM) position sometime after 19,000 years ago. However, the corrosive waters circulating around Antarctica has prevented the recovery of radiocarbon-dateable material, hindering the development of deglacial chronologies. During Expedition NBP1502B to the eastern Ross Sea, an unprecedented quantity of fossil foraminifera and bivalves were recovered. Radiocarbon-dated specimens have been used to constrain the timing of West-AIS retreat from Whales Deep basin and Ross Bank. Whales Deep samples show that the WAIS retreated from its LGM position on the continental shelf edge by 14,700 ± 400 calibrated radiocarbon …

Evaluation Of Winter Management Methods To Enhance Survival Of The Giant Salvinia Weevil, Cyrtobagous Salviniae, Lori Robyn Moshman

LSU Master's Theses

Giant salvinia (Salvinia molesta Mitchell) is a noxious aquatic weed in the southeastern United States. Dense plant mats create ecological and economic consequences by displacing native species and impacting freshwater industries. Biological control programs using the salvinia weevil (Cyrtobagous salviniae Calder and Sands, Coleoptera: Curculionidae) have limited efficacy in giant salvinia’s northernmost range due to the weevil’s low cold tolerance and long-term establishment rates. Spunbonded polypropylene (SBP) fabrics and manipulation of plant density were evaluated as two strategies for managing giant salvinia mats during winter. Greenhouse, laboratory, and field experiments were conducted to determine the suitability of these …

Transcription-Driven Dna Methylation Setting On The Mouse Peg3 Locus, Corey L. Bretz, Joomyeong Kim

Faculty Publications

© 2017 Taylor & Francis Group, LLC. The imprinting of the mouse Peg3 domain is controlled through the Peg3-DMR, which obtains its maternal-specific DNA methylation during oogenesis. In the current study, we deleted an oocyte-specific alternative promoter, termed U1, which is localized 20 kb upstream of the Peg3-DMR. Deletion of this alternative promoter resulted in complete removal of the maternal-specific DNA methylation on the Peg3-DMR. Consequently, the imprinted genes in the Peg3 domain become biallelic in the mutants with maternal transmission of the deletion. Expression levels of the imprinted genes were also affected in the mutants: 2-fold upregulation of Peg3 …

Multigeneration Effects Of Chronic Exposure To Polycyclic Aromatic Hydrocarbons In Gulf Killifish (Fundulus Grandis), Andrea Yammine

LSU Master's Theses

The goal of this study was to examine potential adaptation within two generations of Gulf killifish exposed to polycyclic aromatic hydrocarbons (PAH) while also investigating the use of mucus as an effective and non-lethal alternative to determine concentrations of 11-ketotestosterone (11-KT) and vitellogenin (VTG) of F. grandis. Multiple biomarkers were used to assess adaptation within these fish, such as lysozyme (enzyme critical in innate immunity), and 11-ketotestosterone and vitellogenin (endocrine hormones often affected by PAHs).

Mucal concentrations of 11-KT and VTG were determined and evaluated for effectiveness through comparative assays with blood plasma. This method was then applied to …

A Study Of Application-Awareness In Software-Defined Data Center Networks, Chui-Hui Chiu

LSU Doctoral Dissertations

A data center (DC) has been a fundamental infrastructure for academia and industry for many years. Applications in DC have diverse requirements on communication. There are huge demands on data center network (DCN) control frameworks (CFs) for coordinating communication traffic. Simultaneously satisfying all demands is difficult and inefficient using existing traditional network devices and protocols. Recently, the agile software-defined Networking (SDN) is introduced to DCN for speeding up the development of the DCNCF. Application-awareness preserves the application semantics including the collective goals of communications. Previous works have illustrated that application-aware DCNCFs can much more efficiently allocate network resources by explicitly …

Structural Basis Of Antifreeze Activity Of A Bacterial Multi-Domain Antifreeze Protein, Chen Wang, Svetlana Pakhomova, Marcia E. Newcomer, Brent C. Christner, Bing Hao Luo

Faculty Publications

© 2017 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Antifreeze proteins (AFPs) enhance the survival of organisms inhabiting cold environments by affecting the formation and/or structure of ice. We report the crystal structure of the first multi-domain AFP that has been characterized. The two ice binding domains are structurally similar. Each consists of an irregular β-helix with a triangular cross-section and a long α-helix that runs parallel on one side …

Diversity Of Arthropods In Farmed Wetlands In The Gulf Of Mexico Coastal Plain And Effects Of Detrital Subsidies, Nathan Mercer, Michael D. Kaller, Michael J. Stout

Faculty Publications

© 2016 The Author(s). Wetland acreage has declined continentally in the USA. With the loss of natural wetlands, farmed wetlands may be a surrogate for natural wetlands. Seasonally, flooded rice fields are commonly managed wetlands on the Gulf of Mexico Coastal Plain. This study had two objectives: (1) catalog arthropod diversity in rice fields; (2) investigate if detrital subsidies could elicit trophic cascades that reduce nuisance organisms. In 2013 and 2014, experimental rice plots were established, and detritus was applied to half of the plots in each year. Floating pitfall traps, aquatic D-net sweeping, Gee crawfish traps and root/sediment corers …

Cysteines And N-Glycosylation Sites Conserved Among All Alphaherpesviruses Regulate Membrane Fusion In Herpes Simplex Virus 1 Infection, Paul J.F. Rider, Misagh Naderi, Scott Bergeron, Vladimir N. Chouljenko, Michal Brylinski, Konstantin G. Kousoulas

Faculty Publications

© 2017 American Society for Microbiology. Neurotropism is a defining characteristic of alphaherpesvirus pathogenicity. Glycoprotein K (gK) is a conserved virion glycoprotein of all alphaherpesviruses that is not found in other herpesvirus subfamilies. The extracellular amino terminus of gK has been shown to be important to the ability of the prototypic alphaherpesvirus herpes simplex virus 1 (HSV-1) to enter neurons via axonal termini. Here, we determined the role of the two conserved N-linked glycosylation (N48 and N58) sites of gK in virus-induced cell fusion and replication. We found that N-linked glycosylation is important to the regulation of HSV-1-induced membrane fusion …