Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 16 of 16

Full-Text Articles in Entire DC Network

Preliminary Multifactorial Analysis Of Parkinson's Disease, Max James Miller Jan 2014

Preliminary Multifactorial Analysis Of Parkinson's Disease, Max James Miller

LSU Master's Theses

Neurodegenerative disorders affect millions of Americans every year. Incidence increases as the human population ages. Parkinson’s Disease, a neurodegenerative disorder in the dopaminergic system of the basal ganglia, causes deterioration of movement as the disease progresses. Researchers have attempted to figure out what causes PD and are currently examining it as an environmental disease. This study examined PD as an environmental disease using a multifactorial approach. Methods included 1) utilization of hospital and mortality records in order to investigate a relationship between occupation and PD 2) using ArcGIS 10.2 technology to examine the spatial components of PD 3) conducting Chi-Square …


Prevalence Of Blue Crab (Callinectes Sapidus) Diseases, Parasites, And Symbionts In Louisiana, Holly Rogers Jan 2014

Prevalence Of Blue Crab (Callinectes Sapidus) Diseases, Parasites, And Symbionts In Louisiana, Holly Rogers

LSU Master's Theses

Research on blue crab diseases, parasites, and symbionts has been sporadic in the Gulf of Mexico. Understanding the prevalence of diseases, parasites, and symbionts is important for managers to set informed regulations for the commercial industry and to understand the impacts of environmental disasters on aquatic animal health. The objective of this research was to determine the prevalence of Lagenophrys callinectes, Urosporidium crescens, Hematodinium perezi, Loxothylacus texanus, reo-like virus (RLV), shell rot, and Vibrio spp. in crabs collected from four coastal locations and four shedding facilities in 2013 and the beginning of 2014. Additionally, I determined the prevalence of white …


A Comparison Of Capacity For Resilience Among Coastal Communities In The Northeast U.S. And The Northern Gulf Of Mexico Region, Emily Gootee Jan 2014

A Comparison Of Capacity For Resilience Among Coastal Communities In The Northeast U.S. And The Northern Gulf Of Mexico Region, Emily Gootee

LSU Master's Theses

Coastal communities face many threats from their surrounding environment, including floods and severe storms. These threats are exacerbated by climate change and sea level rise, which may cause increased frequency and severity of these events. Despite these hazards, population density along the coasts continues to rise. These areas of dense population and infrastructure are highly vulnerable to extreme weather events. Hurricane Sandy of 2012 was a powerful demonstration of the impact that severe storms can have on coastal populations. In the face of this reality, coastal communities must adapt and become more resilient to environmental changes. In order to assess …


Development Of An Alternative Bait For The Louisiana Commercial Blue Crab (Callinectes Sapidus) Fishery, Angelle Nicole Anderson Jan 2014

Development Of An Alternative Bait For The Louisiana Commercial Blue Crab (Callinectes Sapidus) Fishery, Angelle Nicole Anderson

LSU Master's Theses

The blue crab (Callinectes sapidus) is a commercially, recreationally, and ecologically important species in Louisiana coastal waters. Louisiana landings account for more than 80% of Gulf of Mexico hard crab landings. In 2012, over 24 thousand metric tons of blue crab were landed in Louisiana with an economic value over $52 million. The blue crab fishery in the northern Gulf of Mexico relies heavily on Atlantic menhaden (Brevoortia tyrannus) for bait, which is a species with stock concerns resulting in approximately a 20% decrease in total allowable catch beginning in 2013. Decreased landings results in increased cost of B. tyrannus …


Hydraulic Fracturing: A Look At Efficiency In The Haynesville Shale And The Environmental Effects Of Fracking, Emily Celeste Jackson Jan 2014

Hydraulic Fracturing: A Look At Efficiency In The Haynesville Shale And The Environmental Effects Of Fracking, Emily Celeste Jackson

LSU Master's Theses

Hydraulic fracturing has become a hot topic in America’s growing, domestic, oil and natural industry. This new technology has provided an economic way to extract resources from tight oil and gas shale formations found deep underground, but this new way of drilling does not come without environmental and human health effects. Among these health effects are water usage, water quality, and air quality. In this paper, data from Frac Focus.org was used to get the average amount of water used per well, and the average amount of chemicals, and what those chemicals are, for each well in the Haynesville Shale. …


Analysis Of Soil And Groundwater Microbial Population Dynamics At In Situ Bioremediation Sites In California And Texas, Farrar C. Stewart Jan 2014

Analysis Of Soil And Groundwater Microbial Population Dynamics At In Situ Bioremediation Sites In California And Texas, Farrar C. Stewart

LSU Master's Theses

Traditional methods for assessing in situ microbial communities often provide limited information on substrate utilization in bioremediation processes. The goal of this research was to assess new methods for describing the microbial communities found in the groundwater and affected contaminated soils documenting changes in community structure, population dynamics, substrate utilization and biodegradation of constituents of concern (CoC) during a site remediation. Two in situ bioremediation pilot studies using biological plugs are being conducted, one in the California San Francisco Bay Area (Sunnyvale) and one in the East Texas Piney Woods (Longhorn). The hypothesis is that changes in community structure, population …


Effects Of Salinity And Temperature On Bioelectrical Impedance Analysis Of Gulf Killifish, Fundulus Grandis, Shea A. Miller Jan 2014

Effects Of Salinity And Temperature On Bioelectrical Impedance Analysis Of Gulf Killifish, Fundulus Grandis, Shea A. Miller

LSU Master's Theses

Bioelectrical impedance analysis (BIA) has been proposed as an easy and accurate technique for a non-lethal index of condition in fish; however, factors affecting its accuracy have yet to be properly identified. The technique uses the resistance (R) and reactance (Xc) of water and lipids in contiguous tissues to estimate lipid content. Studies have investigated the use of BIA on fish, but with mixed results, possibly caused by unrecognized sources of influences. Our study explored possible sources of variance for BIA measurements in gulf killifish, Fundulus grandis, through laboratory feeding and fasting experiments, and experimental exposures to acute changes in …


Determination Of Predominant Species Of Oil-Degrading Bacteria In The Oiled Sediment In Barataria Bay, Louisiana, Lauren Nicole Navarre Jan 2014

Determination Of Predominant Species Of Oil-Degrading Bacteria In The Oiled Sediment In Barataria Bay, Louisiana, Lauren Nicole Navarre

LSU Master's Theses

The effects of the Deepwater Horizon (DWH) oil spill on the bacterial communities in coastal sediments are relatively known but few studies have been published evaluating the impacts of the spill on oil-degrading bacterial populations in the salt marsh sediments of Barataria Bay, Louisiana. The aims of this study were to determine the effects of the oil spill on the microbial community in Barataria Bay, Louisiana through the determination of predominate species of oil-degrading bacteria in marsh sediments, and to determine how well certain bacterial isolates can degrade crude oil in the region by taking samples from three areas of …


Sediment Patterns In Relation To Vegetative Community Shifts At Catahoula Lake, Louisiana, Karen Doerr Latuso Jan 2014

Sediment Patterns In Relation To Vegetative Community Shifts At Catahoula Lake, Louisiana, Karen Doerr Latuso

LSU Master's Theses

The processes that control species composition and structure in wetland ecosystems are complex and controlled by many factors including seasonality, depth and duration of flooding, and nutrient dynamics. Catahoula Lake is a floodplain lake that has existed with seasonally fluctuating water levels for at least 4,000 years. The herbaceous vegetation that attracts these waterfowl is slowly being outcompeted by woody vegetation, most notably water-elm (Planera aquatica). Our general goal is to understand the processes that cause this shift, focusing on the role of sediments. Our first objective was to use historical aerial imagery to detect historical changes in plant communities …


Effect Of Hydrologic, Geomorphic, And Vegetative Conditions On Avian Communities In The Middle Rio Grande Of New Mexico, Sarah G. Hamilton Jan 2014

Effect Of Hydrologic, Geomorphic, And Vegetative Conditions On Avian Communities In The Middle Rio Grande Of New Mexico, Sarah G. Hamilton

LSU Master's Theses

Anthropogenic regulation of the Middle Rio Grande (MRG) of New Mexico has altered the hydrogeomorphology of the system and led to a rapid decline in breeding riparian-obligate birds as native riparian forests are replaced by exotic tamarisk stands. In this study, I evaluated the relationships among hydrogeomorphology, vegetation structure and composition, and avian communities of the San Acacia Reach (SAR) of the MRG. I conducted avian point count surveys and collected habitat data to determine avian community structure and abundance, geomorphic feature, surface flooding, and vegetation structure and composition along 44 transects throughout the SAR. A total of 999 point …


Growth And Mortality Of Spat, Seed, And Market-Sized Oysters (Crassostrea Virginica) In Low Salinities And High Temperatures, Molly Marie Rybovich Jan 2014

Growth And Mortality Of Spat, Seed, And Market-Sized Oysters (Crassostrea Virginica) In Low Salinities And High Temperatures, Molly Marie Rybovich

LSU Master's Theses

Changes in the timing and interaction of seasonal high temperatures and low salinity as predicted by climate change models could dramatically alter oyster population dynamics. Little is known explicitly about how low salinity and high temperature combinations affect spat (<25 mm), seed (26-75 mm), and market (>75 mm) oyster growth and mortality. Using lab and field studies, this project quantified the combined effects of extremely low salinities (< 5) and high temperatures (>30 oC) on growth and survival of spat, seed, and market-sized oysters. In 2012 and 2013, hatchery-produced oysters were placed in open and closed bags at three sites in Breton Sound, LA, along a salinity gradient which typically …


Habitat Associations Of Lower Mississippi River Floodplain Fishes On St. Catherine Creek National Wildlife Refuge, Alonda Mccarty Jan 2014

Habitat Associations Of Lower Mississippi River Floodplain Fishes On St. Catherine Creek National Wildlife Refuge, Alonda Mccarty

LSU Master's Theses

Each year, floodplain habitats are inundated and dewatered throughout the lower Mississippi River during the flood pulse. Many organisms, particularly fishes, are facultative or obligate users of inundated floodplain habitats for foraging and reproduction. The abundance and distribution of these fishes are influenced by annual floods, ranging from weeks to months depending on intensity and duration of the pulse. One major consequence of anthropogenic alterations to the river has been the sequential loss of connectivity of floodplain habitats. In light of these changes, a concentrated effort has been made to restore the integrity of the LMR floodplain. An integral part …


Dgge Analysis Of Denitrifying Bacterial Diversity In Response To Nutrients And Oil Contamination In Salt Marshes, Catalina Restrepo Jan 2014

Dgge Analysis Of Denitrifying Bacterial Diversity In Response To Nutrients And Oil Contamination In Salt Marshes, Catalina Restrepo

LSU Master's Theses

Salt marsh ecosystems located at the Mississippi River delta are exposed to high levels of point and nonpoint sources of nutrients such as nitrate-based fertilizers and to oil spills in the Gulf of Mexico. However, there is little information on the effects of eutrophication and oil contamination on the bacterial diversity of denitrifying bacteria in salt marsh sediments of coastal Louisiana. The effects of excess nutrients on the bacterial diversity of denitrifiers were analyzed by injecting sediment cores with high concentrations of nitrate (100μM NO3- and 20,000μM NO3-) and carbon (0% and 20% C concentration from the original sample). After …


The Adoption Of State Wetland Policies: How Do Wetlands Fit Within The Theoretical Framework Of Environmental Policy Determinants?, Rachel Bogart Krech Jan 2014

The Adoption Of State Wetland Policies: How Do Wetlands Fit Within The Theoretical Framework Of Environmental Policy Determinants?, Rachel Bogart Krech

LSU Master's Theses

Wetlands are an extremely important natural resource in the United States. They offer storm surge protection, sediment stabilization, groundwater recharging, carbon sequestration, and habitat for many species. Despite their values, wetlands have a long history of being misunderstood. It was not until the mid-1970s that scientific understanding helped transform policy from that of rapid conversion to that of conservation. By this time, the lower 48 states had already lost 53 percent of its total wetlands. The nature of wetlands and federal limitations make the management of this natural resource a primarily state-based responsibility. However, the way that states construct their …


History, Nesting Population, Migration, Home Range And Habitats Used By Louisiana Bald Eagles, Nickolas Ryan Smith Jan 2014

History, Nesting Population, Migration, Home Range And Habitats Used By Louisiana Bald Eagles, Nickolas Ryan Smith

LSU Master's Theses

The population of Bald Eagles (Haliaeetus leucocephalus) nesting in Louisiana reached precariously low numbers in the early 1970’s, and although the population has since increased markedly, resident eagles remain a species of conservation concern in Louisiana. Using statewide aerial nest survey data from 1975–2008, I documented the history and quantified the recovery of the nesting population in Louisiana. Known active nests increased exponentially from 7 to 387 during this period, exhibiting a mean annual rate of increase of 11.1 ± 0.3% per year with no indications of slowing. By 1990, the nesting population in Louisiana had exceeded all goals of …


Dissolved Oxygen Dynamics And Modeling - A Case Study In A Subtropical Shallow Lake, Zhen Xu Jan 2014

Dissolved Oxygen Dynamics And Modeling - A Case Study In A Subtropical Shallow Lake, Zhen Xu

LSU Master's Theses

As one of the most valued and treasured natural resources, today many lakes in the world face degradation of their water quality due to nutrient enrichment, toxic contamination, and hydrological modification from their drainage areas. Among various water quality impairments, dissolved oxygen (DO) depletion is often a leading stressor in lake systems. Despite numerous studies on DO in deep water lakes in temperate regions, the knowledge of DO dynamics in eutrophic shallow lakes in subtropical regions is still limited. This thesis research conducted intensive DO monitoring in an eutrophic shallow lake in south Louisiana to characterize diel cycles of DO …