Digital Commons Network^™

Sandy Dredge Pit Sedimentation – Characteristics And Processes In Caminada Borrow Area, Ship Shoal, Louisiana Shelf, Usa, Zehao Xue

LSU Master's Theses

Mississippi River Deltaic Plain’s barrier islands are undergoing rapid disintegration due to high rates of subsidence and a deficit in coastal sediment supply. To mitigate for barrier island land loss, Louisiana has implemented a restoration program that supplements coastal sediment deficits by introducing sand from outside of the active coastal system. Ship Shoal is an inner-shelf submarine shoal with large amounts of restoration quality sand that was dredged in 2013-2016 for the Caminada Headland Restoration Project in central Louisiana, USA.

Vibracore samples (1.5 - 3.5 m deep) collected in 2017 and 2018 in Caminada Borrow Area revealed new silts and …

Immune Gene Diversity And Populations Structure Of Reticulated Flatwoods Salamander (Ambystoma Bishopi), Steven Tyler Williams

LSU Master's Theses

Reticulated flatwoods salamander (Ambystoma bishopi) populations began decreasing dramatically in the late 1900s. Contemporary populations are small, isolated, and may be susceptible to inbreeding and reduced adaptive potential because of low genetic variation. Genetic variation at immune genes is especially important as it influences disease susceptibility and adaptation to emerging infectious pathogens, a central conservation concern for declining amphibians. Connectivity between isolated populations is also vital to maintain genetic diversity and avoid inbreeding. I collected tissue samples from across the extant range of this salamander to examine genetic variation and population structure in: immune genes broadly (immunome), the …

A Deda Family Membrane Protein Is Required For Burkholderia Thailandensis Colistin Resistance, Pradip R. Panta, Sujeet Kumar, Caroline F. Stafford, Caitlin E. Billiot, Martin V. Douglass, Carmen M. Herrera, M. Stephen Trent, William T. Doerrler

Faculty Publications

© Copyright © 2019 Panta, Kumar, Stafford, Billiot, Douglass, Herrera, Trent and Doerrler. Colistin is a “last resort” antibiotic for treatment of infections caused by some multidrug resistant Gram-negative bacterial pathogens. Resistance to colistin varies between bacterial species. Some Gram-negative bacteria such as Burkholderia spp. are intrinsically resistant to very high levels of colistin with minimal inhibitory concentrations (MIC) often above 0.5 mg/ml. We have previously shown DedA family proteins YqjA and YghB are conserved membrane transporters required for alkaline tolerance and resistance to several classes of dyes and antibiotics in Escherichia coli. Here, we show that a DedA family …

Making Decision Adaptive To Price Uncertainty And Risk Preference: A New Decision-Making Model For Forest Management, Fan Zhang

LSU Doctoral Dissertations

While the forest grows, the price of timber fluctuates. Price uncertainty plays a key role in forestry due to the extended rotation length of growing trees. Like double sides of the same coin, risk preference and uncertainties should be considered together. This is because risk preference represents people’s attitude toward that uncertainty when making management decisions. Risk preference is especially an important issue for forest management because forests are exposed to substantial uncertainties during their long growing period. However, most existing relevant studies either simply overlook the risk preference issue or fail to consider it together with a practical forest …

Using Poultry Litter Ash As A Fertilizer Source For Bermudagrass (Cynodon Dactylon) Establishment And Loblolly Pine (Pinus Taeda) Plantation, Crystal L. Vance

LSU Doctoral Dissertations

Lower solubility of P in poultry litter ash (PLA) than conventional phosphorus (P) fertilizers such as triple superphosphate (TSP) may reduce P losses in drainage and runoff; however, lower P solubility may reduce its efficacy as a P source. A laboratory experiment was conducted to examine the effect of acidity on P release and the effect of different combustion temperatures on P solubility as a prerequisite to the following studies. The first research objective was to determine the effect of soil pH on the efficiency of PLA relative to TSP for establishment of common bermudagrass (Cynodon dactylon L.) and …

The Impact Of Anthropogenic Noise On Fish Behavior, Communication, And Development, Julie Butler

LSU Doctoral Dissertations

Noise pollution is pervasive to nearly all aquatic and terrestrial ecosystems and was labeled a pollutant of global concern by the World Health Organization in 2011. In the past few decades, underwater ambient noise levels have risen almost 30 dB SPL re: 1 µPa in the frequency range that most fish produce and detect acoustic stimuli due to rises in shipping, oil exploration, and pile driving. Changes to the natural soundscape can impact almost all aspects of an animal’s life. My dissertation research takes an integrative, whole-animal approach to examining how increased background noise impacts fish behavior, physiology, development, and …

Gulf Of Mexico Hypoxia: Past, Present, And Future, Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

One of the largest human-caused areas of bottom-water oxygen deficiency in the coastal ocean is on the northern Gulf of Mexico continental shelf adjacent to the Mississippi River, which discharges nitrogen and phosphorus loads into its surface waters. The beginnings of seasonal hypoxia (≤2 mg l−1 dissolved oxygen) in this area was in the 1950s with an acceleration in the worsening of severity during the 1970s. Currently, the bottom area of hypoxic areas can approach 23,000 km2, and the volume, 140 km3. Ecosystems, people, and economies are now at risk within the Mississippi River watershed and in the northern Gulf …

Bta-Mir-24-3p Controls The Myogenic Differentiation And Proliferation Of Fetal, Bovine, Skeletal Muscle-Derived Progenitor Cells By Targeting Acvr1b, Xin Hu, Yishen Xing, Ling Ren, Yahui Wang, Qian Li, Xing Fu, Qiyuan Yang, Lingyang Xu, Luc Willems, Junya Li, Lupei Zhang

Faculty Publications

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. MicroRNAs modulate a variety of cellular events, including skeletal muscle development, but the molecular basis of their functions in fetal bovine skeletal muscle development is poorly understood. In this study, we report that bta-miR-24-3p promotes the myogenic differentiation of fetal bovine PDGFRα- progenitor cells. The expression of bta-miR-24-3p increased during myogenic differentiation. Overexpression of bta-miR-24-3p significantly promoted myogenic differentiation, but inhibited proliferation. A dual-luciferase assay identified ACVR1B as a direct target of bta-miR-24-3p. Similarly, knocking down ACVR1B by RNA interference also significantly inhibited proliferation and promoted the differentiation of bovine PDGFRα- …

Incubation Recess Behaviors Influence Nest Survival Of Wild Turkeys, Nicholas W. Bakner, Bret A. Collier, Landon R. Schofield

Faculty Publications

In ground nesting upland birds, reproductive activities contribute to elevated predation risk, so females presumably use multiple strategies to ensure nest success. Identification of drivers reducing predation risk has primarily focused on evaluating vegetative conditions at nest sites, but behavioral decisions manifested through movements during incubation may be additional drivers of nest survival. However, our understanding of how movements during incubation impact nest survival is limited for most ground nesting birds. Using GPS data collected from female Eastern Wild Turkeys (n = 206), we evaluated nest survival as it relates to movement behaviors during incubation, including recess frequency, distance traveled …

Detection Of Chalk In Single Kernels Of Long-Grain Milled Rice Using Imaging And Visible/Near-Infrared Instruments, Christopher K. Addison

Faculty Publications

Background and objectives To maintain the competitiveness of U.S. long-grain rice in U.S. and foreign markets, having translucent whole milled grain is critical. An objective technique to detect grain chalk, opaque areas in the grain, will provide breeders and industry with an effective tool for developing low-chalk varieties or agronomic practices that reduce chalk occurrence. Two instruments developed at the Center for Grain and Animal Health Research, U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), a single-kernel near-infrared (SKNIR) tube instrument and a silicon-based light-emitting diode (SiLED) high-speed sorter, were compared with two commercially available imaging instruments, WinSEEDLE and SeedCount used …

Electrospray Photochemical Oxidation Of Proteins, Remilekun O. Lawal, Fabrizio Donnarumma, Kermit K. Murray

Faculty Publications

© 2019, American Society for Mass Spectrometry. Photooxidation of peptides and proteins by pulsed ultraviolet laser irradiation of an electrospray in the ion source of a mass spectrometer was demonstrated. A 193-nm excimer laser at 1.5-mJ pulse energy was focused with a cylindrical lens at the exit of a nanoelectrospray capillary and ions were sampled into a quadrupole time-of-flight mass spectrometer. A solution containing a peptide or protein and hydrogen peroxide was infused into the spray at a flow rate of 1 μL/min using a syringe pump. The laser creates OH radicals directly in the spray which modify biomolecules within …

Ronald P. Kiene: Major League Pitching Prospect, Avid Sports Fisherman, And Biogeochemist Who Probed The Mysteries Of The Oceanic Organosulfur Cycle, Ronald S. Oremland, Gary King, Pieter Visscher, Douglas G. Capone

Faculty Publications

No abstract provided.

Testing Predictability Of Disease Outbreaks With A Simple Model Of Pathogen Biogeography, Tad A. Dallas, Colin J. Carlson, Timothée Poisot

Faculty Publications

© 2019 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited. Predicting disease emergence and outbreak events is a critical task for public health professionals and epidemiologists. Advances in global disease surveillance are increasingly generating datasets that are worth more than their component parts for prediction-oriented work. Here, we use a trait-free approach which leverages information on the global community of human infectious diseases to predict the biogeography of pathogens through time. Our approach takes pairwise dissimilarities between countries’ pathogen …

Binding Site Matching In Rational Drug Design: Algorithms And Applications, Misagh Naderi, Jeffrey Mitchell Lemoine, Rajiv Gandhi Govindaraj, Omar Zade Kana, Wei Pan Feinstein, Michal Brylinski

Faculty Publications

© 2018 The Author(s) 2018. Published by Oxford University Press. All rights reserved. Interactions between proteins and small molecules are critical for biological functions. These interactions often occur in small cavities within protein structures, known as ligand-binding pockets. Understanding the physicochemical qualities of binding pockets is essential to improve not only our basic knowledge of biological systems, but also drug development procedures. In order to quantify similarities among pockets in terms of their geometries and chemical properties, either bound ligands can be compared to one another or binding sites can be matched directly. Both perspectives routinely take advantage of computational …

A Bayesian Adaptive Phase Ii Clinical Trial Design Accounting For Spatial Variation, Beibei Guo, Yong Zang

Faculty Publications

Conventional phase II clinical trials evaluate the treatment effects under the assumption of patient homogeneity. However, due to inter-patient heterogeneity, the effect of a treatment may differ remarkably among subgroups of patients. Besides patient’s individual characteristics such as age, gender, and biomarker status, a substantial amount of this heterogeneity could be due to the spatial variation across geographic regions because of unmeasured or unknown spatially varying environmental and social exposures. In this article, we propose a hierarchical Bayesian adaptive design for two-arm randomized phase II clinical trials that accounts for the spatial variation as well as patient’s individual characteristics. We …

Emergent Functional Behaviour Of Humic Substances Perceived As Complex Labile Aggregates Of Small Organic Molecules And Oligomers, Robert L. Cook

Faculty Publications

The structural organisation of humic substances (HS) has been a central question of earth sciences for several decades. The latest experimental results have led to the recognition of HS as complex mixtures of small molecules and oligomers. We investigate the correlation between the chemical composition of HS, perceived as labile aggregates, and the emergent functions. Computational modelling was used to help to understand the processes and mechanisms on the molecular scale that occur in different fractions of the HS, fulvic acids (FA) and humic acids (HA), as they interact with metal ions and organic pollutants. The importance of non-covalent interactions …

Avian Ecological Succession In The Amazon: A Long-Term Case Study Following Experimental Deforestation, Cameron L. Rutt, Vitek Jirinec

Faculty Publications

Approximately 20% of the Brazilian Amazon has now been deforested, and the Amazon is currently experiencing the highest rates of deforestation in a decade, leading to large-scale land-use changes. Roads have consistently been implicated as drivers of ongoing Amazon deforestation and may act as corridors to facilitate species invasions. Long-term data, however, are necessary to determine how ecological succession alters avian communities following deforestation and whether established roads lead to a constant influx of new species. We used data across nearly 40 years from a large-scale deforestation experiment in the central Amazon to examine the avian colonization process in a …

Effect Of F1 And F2 Generations On Genetic Variability And Working Steps Of Doubled Haploid Production In Maize, Evellyn Giselly De Oliveira Couto, Mayara Neves Cury, Massaine Bandeira E Souza, Ítalo Stefanine Correia Granato, Miriam Suzane Vidotti, Deoclécio Domingos Garbuglio, José Crossa, Juan Burgueño, Roberto Fritsche-Neto

Faculty Publications

For doubled haploid (DH) production in maize, F1 generation has been the most frequently used for haploid induction due to facility in the process. However, using F2 generation would be a good alternative to increase genetic variability owing to the additional recombination in meiosis. Our goals were to compare the effect of F1 and F2 generations on DH production in tropical germplasm, evaluating the R1-navajo expression in seeds, the working steps of the methodology, and the genetic variability of the DH lines obtained. Sources germplasm in F1 and F2 generations were crossed with the tropicalized haploid inducer LI-ESALQ. After harvest, …

The Power Of Wording: An Evaluation Of Framing Effects, Chelsea Romph

Honors Capstones

No abstract provided.

Review Of Naturally Occurring Ammonia In Groundwater And Its Effect On Using Chloramines For Drinking Water Disinfection In Louisiana, Athena Lindsay

Honors Capstones

No abstract provided.

The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood

LSU Doctoral Dissertations

Lampreys (Petromyzontiformes) are jawless vertebrates with an evolutionary history lasting at least 360 million years and are often used in comparisons with jawed vertebrates because some of their morphological aspects, such as the segmented trunk musculature with curved myosepta and a non-mineralized skeleton fibrous skeleton, are thought to resemble the condition of early vertebrates before the evolution of jaws. Although earlier authors studied the morphology of the skeleto-muscular system of the trunk of lampreys, their studies are not detailed and complete enough to allow a functional and biomechanical analysis that is needed as a basis for modeling the mechanics of …

Prevalence And Control Of Salmonella Spp. And Sanitary Indicator Microorganisms In Wild Caught And Farm Raised Catfish (Ictalurus Punctatus), Bilan Costley Jessie

LSU Doctoral Dissertations

Catfish inspections have transitioned from the U.S. Food and Drug Administration (FDA) to the United States Department of Agriculture (USDA). The USDA Food Safety and Inspection Service (FSIS) and Food Emergency Response Network (FERN) consider it important to assess the food safety risk associated with consuming catfish in the United States. Surveillance of farm-raised and wild-caught catfish for pathogens is relevant as a public safety protocol. The purpose of this study was to detect the prevalence of Salmonella spp., identify and examine isolates for antibiotic resistance to clinical treatments, evaluate the effectiveness of antimicrobial chemical treatments against Salmonella enterica, and …

Investigations Of Thermal Treatment Of Softwood Kraft Lignin Under Fractional And Ablative Pyrolytic Conditions, Dideolu J. Daniel

LSU Master's Theses

Lignin is second to cellulose in abundance among polymers in nature. Research studies on the development of new products and material combinations in which lignin degradation/conversion products are involved are still in their infancy, because fundamental knowledge about its structure, reactivity, and material and polymer behavior, is still lacking.

The objective of this research study was to investigate the complex thermal deconstruction and mechanistic behavior of a type of technical lignin, known as Kraft lignin, under depolymerization and to develop operating conditions for parameters influencing resulting product yields and operation of pyrolysis reactors.

Softwood Kraft lignin (s-KL) and methanol-fractionated (ex-KL) …

Influence Of The Annual Flood Pulse Of The Atchafalaya River And Updates On The Ecology Of Floodplain Aquatic And Semi-Aquatic Hemiptera And Their Associates, Patricia Ls Wooden

LSU Master's Theses

Understanding the biodiversity of insects in an area provides key insights into the health and uniqueness of an ecosystem. Here we increase the breadth of knowledge of Louisiana aquatic Hemiptera through field and natural history collection research. The Atchafalaya River floodplain is variably inundated throughout the course of the year, peaking with the spring flood pulse, resulting in spatiotemporally dynamic habitats for aquatic organisms. Buffalo Cove Water Management Unit (BC) is within the river system, whereas Lake Fausse Pointe (LFP) has been leveed from the influence of the river for over 50 years. We collected aquatic macroinvertebrates with quatrefoil light …

Evaluating Feline Release Criteria Following Iodine-131 Therapy For Hyperthyroidism, Anthony Davila

LSU Master's Theses

Hyperthyroidism is a very common endocrine disorder in both humans and cats. Radioactive iodine ablation therapy is considered the gold standard; however, the patient becomes a radiation source and poses a potential radiological risk to others. The regulations governing when the patient can be released differ between human medicine and veterinary medicine. A human patient can receive up to 33 mCi of I-131 and be discharged the same day; yet a feline patient can receive a dose as low as 2 mCi and require multiple days of hospitalization. This discrepancy has not been satisfactorily addressed; and overly restrictive release criteria …

Characterizing The Roles Of Nuclear Proteins Dbc1, G9a, And Glp In Adipocyte Function And Metabolic Health, Ashley Ann Able

LSU Doctoral Dissertations

Obesity is a metabolic disorder characterized by excess energy storage in adipose tissue and it increases the risk for Type 2 diabetes. Impaired or altered adipocyte function during obesity can contribute to metabolic dysfunction. DBC1 (deleted in breast cancer 1) and EHMTs 1 and 2 (euchromatic histone lysine methyltransferases 1 and 2) have been shown to have a role in fat cell development and function. DBC1 is typically localized in the nucleus and can regulate a variety of epigenetic modifiers, transcription factors, and nuclear receptors. EHMTs 1 and 2, also known respectively as GLP and G9a, were initially classified as …

Oyster Reefs In Northern Gulf Of Mexico Estuaries Harbor Diverse Fish And Decapod Crustacean Assemblages: A Meta-Synthesis, Megan K. La Peyre, Danielle Aguilar Marshall, Lindsay S. Miller

Faculty Publications

Oyster reefs provide habitat for numerous fish and decapod crustacean species that mediate ecosystem functioning and support vibrant fisheries. Recent focus on the restoration of eastern oyster (Crassostrea virginica) reefs stems from this role as a critical ecosystem engineer. Within the shallow estuaries of the northern Gulf of Mexico (nGoM), the eastern oyster is the dominant reef building organism. This study synthesizes data on fish and decapod crustacean occupancy of oyster reefs across nGoM with the goal of providing management and restoration benchmarks, something that is currently lacking for the region. Relevant data from 23 studies were identified, representing data …

Genomic Selection In Rubber Tree Breeding: A Comparison Of Models And Methods For Managing G×E Interactions, Livia M. Souza, Felipe R. Francisco, Paulo S. Gonçalves, Erivaldo J. Scaloppi Junior, Vincent Le Guen, Roberto Fritsche-Neto, Anete P. Souza

Faculty Publications

Several genomic prediction models combining genotype × environment (G×E) interactions have recently been developed and used for genomic selection (GS) in plant breeding programs. G×E interactions reduce selection accuracy and limit genetic gains in plant breeding. Two data sets were used to compare the prediction abilities of multienvironment G×E genomic models and two kernel methods. Specifically, a linear kernel, or GB (genomic best linear unbiased predictor [GBLUP]), and a nonlinear kernel, or Gaussian kernel (GK), were used to compare the prediction accuracies (PAs) of four genomic prediction models: 1) a single-environment, main genotypic effect model (SM); 2) a multienvironment, main …

Intrusive Advising And Retention Practices In A College Of Agriculture: A Case Study Of First-Year Student Experiences, Amanda Martin

LSU Doctoral Dissertations

The purpose of this qualitative case study was to explore the perceptions of first-year students who experienced intrusive advising and retention initiatives in the College of Agriculture at Louisiana State University (LSU). Research participants consisted of 20 first-year students enrolled in the college in the fall of 2018. One-on-one, face-to-face interviews with first-year students were conducted to gain insight and understand student experiences with intrusive advising and retention initiatives within the College of Agriculture. College student retention and factors that contribute to understanding retention have been extensively studied (Astin, 1993; Braxton, Hirschy, & McClendon, 2004; Habley, Bloom, & Robbins, 2012; …

Equine Hoof Stratum Internum K14+Cd105+ Progenitor Cells: Culture, Characterization, And Model Of Epithelial To Mesenchymal Transition, Qingqiu Yang

LSU Doctoral Dissertations

For the potential benefit of progenitor cells to be realized in cell-based clinical therapies, it is vital to investigate the mechanism between progenitor cells and abnormal tissue formation. Laminitis is a fatal condition that is often presented by equine hoof inflammation and hoof tissue disarrangement. The persistence of abnormal tissue formation after the resolution of equine laminitis suggests there is progenitor cell compromise. So far, there is limited information about equine hoof progenitor cells and the effects of inflammation on hoof progenitor cells. To pursue a better understanding of both hoof progenitor cell and hoof growth as well as find …