Life Sciences Commons^™

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 …

Influence Of Nitrogen And Sprig Planting Rates On Surface Runoff Losses During 'Latitude 36' Bermudagrass Establishment, Lance A. Rice

LSU Master's Theses

The hybrid bermudagrass (Cynodon dactylon x C. transvaalensis) ‘Latitude 36’ is grown because of its quality, excellent wear tolerance and fast recuperation. Hybrid bermudagrasses are vegetatively propagated as sprigs with N applied to accelerate establishment. Since losses of soil and associated nutrients in runoff are relatively high when ground coverage is low, rapid establishment is desirable from an environmental besides aesthetic basis. However, neither the interactive effect of sprig density and N fertilization on the rate of bermudagrass expansion nor soil and nutrient loss during establishment has been carefully examined. The current work measured bermudagrass coverage, runoff volume …

Composition And Ecology Of Avian Communities Along Elevational Gradients In Borneo, Ryan Christian Burner

LSU Doctoral Dissertations

A primary goal of ecology is to explain the diversity and distribution of organisms. Species distributions can be a function of abiotic factors, species interactions, dispersal limitations, and history, but the relative importance of these factors is widely debated. Elevational gradients are useful systems for studying these effects because many of these factors vary predictably with elevation, and because elevational gradients are replicated many times across the earth. However, few quantitative surveys of Southeast Asian bird communities have been conducted along elevational gradients. In this study, I surveyed birds using point counts and measured habitat and temperature across primary forest …

High-Throughput Cultivation Of Bacterioplankton From The Gulf Of Mexico And Genomics Of The First Cultured Ld12 Representative, Michael Winslow Henson

LSU Doctoral Dissertations

Cultivation of microorganisms facilitates characterization of metabolism, interspecies dependencies, virus-host interactions, and other information necessary to resolve the functions and distribution of individual taxa. However, the metabolic and physiological capacities for the majority of microbes remains unresolved because of the lack of cultivated representatives for many groups limits our ability to test cultivation-independent observations. The Northern Gulf of Mexico offers a diversity of ecosystems under the continuous threat from natural and anthropogenic disturbances, yet little is known about its native bacterioplankton community. This dissertation sought to use high-throughput cultivation over three-years at six sites to isolate important coastal bacteria to …

Investigations Into Aspergillus Flavus Infection Of Corn And Regulation Of Aflatoxin Production By Volatiles And Biocontrol Strains, Rebecca R. Sweany

LSU Doctoral Dissertations

Aspergillus flavus is an ascomycete fungus impacting agriculture, public and environmental health due to production of acutely-toxic, carcinogenic aflatoxins in oil seed crops, especially corn in Louisiana, and lung infections of immunocompromised patients resulting in a leading cause of AIDS patients’ deaths globally. The most effective aflatoxin mitigation strategy, biocontrol by atoxigenic A. flavus presents several concerns including: dissemination of a human pathogen, possible sexual reproduction and reliance on precise environmental conditions. Several aspects of A. flavus biology were investigated to potentially improve treatments. Studies investigated how genotypically diverse members within the A. flavus population interact with other population members …

The Development Of A High-Throughput Screening Assay For Acetyl-Coa Carboxylase Using 1,3,6,8-Tetrahydroxynapthalene Synthase, Sarah Elayne Cohen

Honors Capstones

No abstract provided.

Louisiana Agriculture Winter, 2019, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

Dosage Compensation Of The X Chromosomes In Bovine Germline, Early Embryos, And Somatic Tissues, Zongliang Jiang

Faculty Publications

Dosage compensation of the mammalian X chromosome (X) was proposed by Susumu Ohno as a mechanism wherein the inactivation of one X in females would lead to doubling the expression of the other. This would resolve the dosage imbalance between eutherian females (XX) versus male (XY) and between a single active X versus autosome pairs (A). Expression ratio of X- and A-linked genes has been relatively well studied in humans and mice, despite controversial results over the existence of upregulation of X-linked genes. Here we report the first comprehensive test of Ohno's hypothesis in bovine preattachment embryos, germline, and somatic …

Intraguild Predation: Interactions Between Predators, Pathogens, And Their Shared Resources In Crop Pest Communities, Andrew Jason Flick

LSU Doctoral Dissertations

Crop pest management requires an understanding of the complex interactions among pest species that potentially damage crop yield and species that may be crucial for controlling pest species outbreaks. For example, predators, parasitoids, and pathogens are constantly interacting via their shared prey or hosts. Predators may prefer infected prey, which can be easier to catch; however, infected prey may be less nutritious or even lethal for predators. These interactions then dictate the short-term dynamics of host and pathogen as well as between prey and predator. "How these dynamics change as the species in the system change either empirically or theoretically?" …

Phenotypic And Transcriptomic Characterization Of Colonial Phase Variation In The Cholera Pathogen Reveals A Novel Smooth Biofilm-Defective Form, Bliss Nicole Lambert

LSU Doctoral Dissertations

Biofilm formation, through the production of Vibrio polysaccharide (VPS), greatly enhances the environmental fitness and pathogenic success of Vibrio cholerae. As a result of phase variation, V. cholerae can switch from a smooth form to rugose, whose cells produce excess VPS, resulting in highly structured biofilms and greater resistance to stress. To further characterize the reversible process of phase variation, we isolated three colonial lineages. Each lineage began with a smooth parent, N16961, and contained a rugose variant derived from the parent, N16961R, as well as a smooth revertant of the rugose, N16961SD. We found clear phenotypic and transcriptomic …

Physicochemical And Ecotoxicological Assessment Of Biochar For Environmental Application, Maria Guillermina Cantou

LSU Doctoral Dissertations

Multiple benefits of biochar conversion and utilization, including soil carbon sequestration and environmental remediation, have been proposed by researchers. Biochar may be produced from a wide array of feedstocks and pyrolytic process conditions. This influences the final biochar composition, which includes the presence of potential pollutants that could ultimately result in detrimental environmental impacts. The major purpose of this research was to improve our understanding of potential unintended effects of biochar addition to the environment either as a potential source of toxicity towards organisms or as a material influencing availabilities of other soil contaminants. Biochars were produced from ten different …

Changing Land-Use From Pinus Elliottii To Eucalyptus Bentamii In Southwest Louisiana Affects Understory Vegetation Richness, Diversity, And Functional Diversity Patterns, Andrea De Stefano

LSU Doctoral Dissertations

In the Western Gulf region of the United States cold-tolerant eucalyptus have been explored as pulpwood feedstock. However, non-native plantations may alter understory species diversity, modifying environmental conditions and soil characteristics. Few studies have compared eucalyptus plantations with other ecosystems to understand the impacts of converting these land uses on understory vegetation in the United States. Three plantations were selected: (1) slash pine (Pinus elliottii) established in 2008, (2) slash pine established in 2013, and (3) and Camden white gum (Eucalyptus benthamii) established in 2013. The objectives of this study were to: (1) investigate potential changes …

Men’S Jeans Fit Based On Body Shape Categorization, Elahe Saeidi

LSU Doctoral Dissertations

The purpose of this study was to categorize lower body shape in men and to investigate the interplay between body shape and fitting issues appearing in men’s jeans. More specifically, the goal of the study was to improve apparel fit based on body shape. The detailed objectives of the study were to: (1) Categorize male body shapes using statistical analysis; (2) use 3D virtual fitting technology to assess fit and develop a shape-driven pants block pattern for each body shape.

This quantitative study was conducted in three stages: (1) categorizing the body shape of 1420 male scans, aged 18-35, from …

Rats Fed Dietary Bioactive Components (Resistant Starch, Whole Grains, And Fat) Undergo Altered Biometrics And Gene Expression As A Result Of Gut Fermentation, Justin Lamont Guice

LSU Doctoral Dissertations

The whole grain and fat content of the diet have been previously shown to affect intestinal fermentation and phenotype conferred by high–amylose maize resistant starch (HAMRS), a form of fermentable dietary fiber. The current studies were designed to compare rodent gut health following consumption of whole grain and non–whole grain prebiotics on moderate fat (MF) and high fat (HF) diets, and to optimize health effect based on dosage of whole grain resistant starch prebiotics.

Study 1: Diets were prepared to contain the following factors RS (Present/Absent), WG (Present/Absent), and Fat (HF/MF). A three–way ANOVA was performed with statistical slice …

Speciation And Hybridization In Jamaican-Endemic Streamertail Hummingbirds (Trochilus Polytmus And T. Scitulus), Caroline D. Judy

LSU Doctoral Dissertations

Streamertails hummingbirds (Trochilus polytmus and T. scitulus) are recently diverged sister taxa that appear to have speciated in situ on the island of Jamaica. They are distinguished by male bill color, a secondary sexual trait that is coral red in T. polytmus and jet black in T. scitulus. They hybridize in a narrow zone where their ranges meet in eastern Jamaica. In Chapter 2, I performed a formal population survey of T. scitulus to determine the size of the population, which was unknown. I determined that the total population contains well over 100,000 individuals despite its limited …

Transforming Lives In Coastal Communities Through Economic Development: Breeding Crassostrea Virginica For Alternative Oyster Culture, Brian Randall Callam

LSU Doctoral Dissertations

This dissertation helped address the commercialization of triploid Crassostrea virginica production and develop tetraploid C. virginica broodstock in Louisiana by addressing triploid commercialization and tetraploid broodstock development. This was done by: 1) developing regional breeding plans for diploid and tetraploid C. virginica targeted at the Gulf Coastal Region, 2) assessing the effect of chromosome set manipulation on gonadal development in diploid, triploid, and tetraploid C. virginica, 3) quantifying the variation of commercially important hatchery traits in triploid C. virginica larvae from different tetraploid parents, 4) developing an up-to-date remote setting manual for the Gulf Coastal Region for industry use, …

Physiological And Genomic Characterization Of Novel Isolate From Om252 Clade Of The Gammaproteobacteria, Emily Nall

Honors Capstones

No abstract provided.

Intestinal Microbiome Composition Of An Acute In Vivo Alzheimer’S Disease Rat Model, Jimmy Saravia

Honors Capstones

No abstract provided.

Interactions Observed With Clomazone Plus Pendimethalin When Mixed With Postemergence Rice Herbicides, Matthew Osterholt

LSU Master's Theses

A study was conducted at the Louisiana State University Agricultural Center’s H. Rouse Caffey Rice Research Station (RRS) in 2017 and 2018 to evaluate whether the pre-packaged mixture of clomazone plus pendimethalin should be applied delayed preemergence (DPRE) or postemergence (POST) within a herbicide residual overlay with saflufenacil, clomazone, or quinclorac. POST applications also included penoxsulam or halosulfuron in combination with the second residual application. No differences were observed with barnyardgrass control at 14 DAT across all treatments with 92 to 98% control. At 42 DAT, barnyardgrass treated with either clomazone plus pendimethalin applied at either timingin combination with either …

Distribution And Incidence Of Mosaic And Evaluation Of Susceptibility In Louisiana's Current Sugarcane Germplasm, Jancee Rice

LSU Master's Theses

Mosaic is a viral disease of sugarcane caused primarily by Sorghum mosaic virus (SrMV) in Louisiana. Low mosaic incidence has resulted from successful breeding for resistance. However, mosaic was detected in breeding program experimental clones and a new cultivar, HoCP 09-804.Therefore, multiple research approaches were undertaken to assess the current status of mosaic in Louisiana sugarcane and prevent it from re-emerging as an important problem. Field surveys conducted during 2016-2018 of breeding program yield trials and experimental clone seed-cane increases determined disease incidence and distribution. Mosaic was detected in three of five sugarcane production areas and incidence ranged from 0 …

Analysis Of The Soil Health Of Pastures Over-Seeded With Winter Annuals, Kathleen M. Bridges

LSU Doctoral Dissertations

Utilizing winter annuals in livestock pastures reduces feed costs of hay, and provides additional vegetative cover that is beneficial to the soil. However, how this practice affects the soil microbial communities has not been well studied. Two sites were included in this study. Both were commercial cattle grazing operations that over-seeded a mixture of grasses, legumes, and brassicas into pastures dominated by bahiagrass (Paspalum notatum). Soil health was assessed using a suite of physical, chemical, and biological properties. Soil physical assessments included bulk density and aggregate stability. Soil chemical assessments included macronutrients, pH, soil organic matter (SOM), total …

Effect Of Heat Stress On Bovine Follicular Development And Epigenetic Changes, Fabian Andres Diaz

LSU Doctoral Dissertations

Climate is one of the most important limiting factors in animal production. Cattle under the effect of heat stress have reduced fertility. Negative effects during gamete maturation and embryo development have been observed at the morphological, biochemical, transcriptional and developmental levels. Epigenetic mechanisms play a fundamental role in the regulation of gamete and embryo development. Several genes activated during gamete maturation and early embryo development are controlled by epigenetic mechanisms. There are no studies evaluating the effect of heat-stress on the epigenetic profile of bovine oocytes and embryos. Similarly, there is no information on the effect of heat stress on …

Induced Resistance In Rice, Oryza Sativa, To Herbivores In The Southern United States, Emily Clare Kraus

LSU Doctoral Dissertations

The effects of herbivory and chemical applications as potential inducers of resistance to herbivores in rice, Oryza sativa L., were explored through a series of field, greenhouse, and laboratory experiments. Studies were conducted to investigate the preference and performance of several herbivore pests of rice with a focus on, Lissorhoptrus oryzophilus Kuschel, the rice water weevil (RWW), under conditions where rice plants had been stressed by previous herbivory or chemical applications. The effects of defoliation by Spodoptera frugiperda (J.E. Smith), the fall armyworm, on resistance and tolerance of rice to RWW under field conditions were examined. Herbivory by fall …

Synergistic Effects Of Temperature And Salinity On The Gene Expression And Physiology Of Crassostrea Virginica, Hollis Jones

LSU Master's Theses

Crassostrea virginica, the eastern oyster, forms reefs that provide critical services and benefits to the resiliency of the surrounding ecosystem. Changes in environmental conditions, including salinity and temperature, can dramatically alter the services oysters provide by affecting their population dynamics. Climate warming may further exacerbate the effects of salinity changes as precipitation events increase in frequency, intensity, and duration. Temperature and salinity independently and synergistically influence gene expression and physiology in marine organisms. We used comparative transcriptomics, physiology, and a field assessment experiment to investigate whether Louisianan oyster are changing their phenotypes to cope with increased temperature and salinity …

Genome Wide Association Studies For Identification Of Markers Linked To Sucrose Traits In Sugarcane, Nathanael Darrell Fickett

LSU Doctoral Dissertations

Sugarcane, being a complex aneu-polyploid, poses unique challenges to fine mapping of quantitative trait loci (QTL) controlling agronomic traits of interest. Genome-wide association studies (GWAS) could be a better alternative to identify molecular markers associated with specific traits due to high linkage disequilibrium in sugarcane. In the first study, marker-trait associations (MTAs) were evaluated for three sucrose traits, Brix, total recoverable sugar (TRS), and percent sucrose on 48 elite and historic Louisiana breeding clones using 1,062 alleles. These sucrose traits were highly correlated (P-value < 0.0001) at >0.96. TASSEL 5.1 and JMP Genomics 8.0 were compared with eight models run in each program. …

Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, Matthew Ryan Foster

LSU Doctoral Dissertations

In research conducted using indeterminate soybean [Glycine max (L.) Merr.], fourteen injury criteria observed following dicamba at 0.6 to 280 g ae ha^-1 (1/1000 to ½ of 560 g ha^-1 use rate) were rated using a scale of 0= no injury, 1= slight, 2= slight to moderate, 3= moderate, 4= moderate to severe, and 5= severe. Greatest crop injury 15 d after treatment (DAT) was observed following dicamba applied at 0.6 to 4.4 g ha^-1 at V3/V4 for upper canopy pale leaf margins (3.8 to 4.2) and at R1/R2 for terminal leaf cupping (4.1 to 5.0) …

An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn

LSU Master's Theses

Growth models estimate life history parameters that are used in the management of fisheries stocks. The most commonly used growth model in fisheries is the von Bertalanffy growth model (VBGM), yet it has been shown to provide a poor fit for length-at-age data of some species and other models exist. I reviewed 196 peer-reviewed age and growth studies and 50 NOAA stock assessments to examine temporal trends in the use of growth models and model selection in fisheries. I found that the use of multi-model frameworks has increased since the year 2000 and information theoretic approaches are replacing goodness-of-fit and …

Genome-Wide Screening Identifies Genes And Biological Processes Implicated In Chemoresistance And Oncogene-Induced Apoptosis, Tengyu Ko

LSU Doctoral Dissertations

Anti-proliferative responses such as senescence and apoptosis are often used by normal cells to combat oncogenic insults and to prevent tumorigenesis. However, oncogenic mutations are frequently found in cancers, suggesting that additional mutations may occur to facilitate the bypass of these anti-proliferative responses. It is believed that some of these additional mutations may also contribute to the chemoresistance of cancers. This dissertation focused on identifying novel genes and biological processes implicated in chemoresistance and tumorigenesis.

Cisplatin-based chemotherapeutic regimens are frequently used for treatments of solid tumors. However, tumor cells may have inherent or acquired resistance to cisplatin, and the underlying …

A Review Of Current Knowledge Concerning The Breeding And Summer Distribution Of The Cordilleran Flycatcher (Empidonax Occidentalis) In Mexico, Harold F. Greeney, Matthew J. Miller, Charles Van Riper Iii

Occasional Papers of the Museum of Natural Science, Louisiana State University

The Cordilleran Flycatcher (Empidonax occidentalis) is one of many North American birds whose distribution crosses the US–Mexican border and for which little is presently known about summer distribution and breeding biology south of this border. In addition, the Cordilleran Flycatcher presents ornithologists with a number of challenging questions surrounding its taxonomy, migration, distribution, population structure, and species limits. In particular, there remains a good deal of uncertainty concerning the species-level relationships, seasonal movements, and the wintering and breeding distributions of both recognized subspecies of Cordilleran Flycatcher in Mexico. Using field observations, a thorough review of the literature, and …

The Effect Of Acute, Static Stretching On The Gastrocnemius’ Plantarflexion Torque Across Selected Knee And Ankle Combinations, Emile Jeunesse

Honors Capstones

No abstract provided.