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A Multi-Scale Investigation Of Nutrient Dynamics In The Lake Pontchartrain Estuary And Basin, Eric Daniel Roy Jan 2013

A Multi-Scale Investigation Of Nutrient Dynamics In The Lake Pontchartrain Estuary And Basin, Eric Daniel Roy

LSU Doctoral Dissertations

Humans are responsible for global-scale alteration of nitrogen (N) and phosphorus (P) biogeochemical cycles to support food production. Increases in N and P inputs into soils and waste-streams has resulted in excessive nutrient loading to surface waters, including the Mississippi River, leading to eutrophication. Here I investigated N and P dynamics occurring in the Lake Pontchartrain Estuary and Basin. I measured two biogeochemical processes using intact sediment core incubations and quantified their importance in the context of nutrient-rich Mississippi River flood diversions through the Bonnet Carré Spillway. I show that diffusion of nitrate-N into sediments accounts for a substantial magnitude …


Amplifying Conjugated Polymers For Fluorescent Chemosensing, Deepa Pangeni Jan 2013

Amplifying Conjugated Polymers For Fluorescent Chemosensing, Deepa Pangeni

LSU Doctoral Dissertations

Chemo- and biosensors based on fluorescent conjugated polymers benefit from greater detection sensitivity due to amplification of the electronic perturbations produced by analyte binding. This amplification stems from the exciton-transporting properties of conjugated polymers. In the conventional sensor design paradigm, excitons migrate from the bulk of the polymer to the analyte binding sites which can be either fluorescence quenching sites (turn-off sensors) or lower energy fluorophores (turn-on sensors). In this dissertation, we proposed an alternative design paradigm when analyte binding creates a higher energy gap site in the polymer backbone. In the case of isolated polymer chains in dilute solution, …


Scanning Probe Investigations Of The Surface Self-Assembly Of Organothiols And Organosilanes Using Nanoscale Lithography, Tian Tian Jan 2013

Scanning Probe Investigations Of The Surface Self-Assembly Of Organothiols And Organosilanes Using Nanoscale Lithography, Tian Tian

LSU Doctoral Dissertations

Particle lithography and scanning probe lithography were applied to study the kinetics and mechanisms of surface self-assembly processes. Organothiols on Au(111) and organosilane on Si(111) were chosen as model systems for investigations at the nanoscale using atomic force microscopy (AFM). Fundamental insight of structure/property interrelationships and understanding the properties of novel materials are critical for developments with molecular devices. Methods using an AFM probe for nanofabrication have been applied successfully to prepare sophisticated molecular architectures with high reproducibility and spatial precision. The established capabilities of AFM-based nanografting were reviewed for inscribing patterns of diverse composition, to generate complicated surface designs …


Taxonomy And Systematics Of New Zealand Faronitae (Coleoptera: Staphylinidae: Pselaphinae), Jong-Seok Park Jan 2013

Taxonomy And Systematics Of New Zealand Faronitae (Coleoptera: Staphylinidae: Pselaphinae), Jong-Seok Park

LSU Doctoral Dissertations

The New Zealand Faronitae was revised at the species level, and a phylogenetic study was performed based on morphological and molecular data. Eight new genera and 143 new species were discovered. Three new genera, “Brounea”, “Ahnea” and “Pseudoexeirarthra” were designated based on the species originally described in the genus Sagola. Five new genera, “Aucklandea”, “Chandlerea”, “Nunnea”, “Leschenea” and “Pseudostenosagola” were designated by new species. Three known genera, Exeirarthra, Stenosagola and Sagola were also revised at species level. Eighty four names were synonymized, two in Exeirarthra, four in Stenosagola and 78 in Sagola. Lectotypes of seven species, Sagola terricola Broun, S. …


Faced With Faces, Donald E. Watkins Jan 2013

Faced With Faces, Donald E. Watkins

LSU Master's Theses

FACED WITH FACES is a contemporary commentary on the male to female relationship. While I’m aware these are not the only relationships formed in our day in age I needed to find a scope and tackle one central theme. The addition of same sex relationships is very important in our society but I couldn’t find a way to weave it in without making it all about that or without it seeming to not fit into the over arcing story. Perhaps in the evolution of this process I can find a way to add more voices that speak to all. The …


The Shoulder Suspension Of Bipedal Humans And The Head Suspension Of Quadrupedal Cats : A Reconstruction Of Macroevolutionary Changes Of Complex Systems Based On Nautral Experiments, Comparative Anatomy, And Biomechanical Analyses Of Extant Organisms, Michelle L. Osborn Jan 2013

The Shoulder Suspension Of Bipedal Humans And The Head Suspension Of Quadrupedal Cats : A Reconstruction Of Macroevolutionary Changes Of Complex Systems Based On Nautral Experiments, Comparative Anatomy, And Biomechanical Analyses Of Extant Organisms, Michelle L. Osborn

LSU Doctoral Dissertations

The biological processes in macroevolutionary transformations, which result in the origin of new species and supraspecific taxa, are not directly observable in organisms with long reproductive generations and need to be extrapolated and reconstructed from physiological, anatomical, and microevolutionary processes. This dissertation reconstructs the anatomical and biomechanical changes that affected the head-neck-shoulder apparatus during the macroevolutionary transformation of a quadrupedal mammal to a bipedal one by studying two model organisms, namely the human and the cat. I hypothesize that the anatomical differences in the head-neck-shoulder apparatus of the two organisms are caused by different force regimes that act on them. …


New Orleans And Fazendeville (De) Segregated : Challenging A Narrative Of School Integration, April Antonellis Jan 2013

New Orleans And Fazendeville (De) Segregated : Challenging A Narrative Of School Integration, April Antonellis

LSU Master's Theses

Too often, “integration” is a word only associated with the 1960s. The dominant narrative of education and integration in the South is simple and linear: African Americans were oppressed, then there was integration, then there was equality. However, in the case of New Orleans, the narrative is not so linear and not nearly so succinct. The conversation on integration began in New Orleans immediately following the Civil War, a century earlier than this conventional starting date, and yet despite generations of successes and drawbacks, the public schools of New Orleans continue to exist segregated today. Examining the narrative of school …


Factors Affecting Teaching Efficacy Of Beginning Secondary Agricultural Education Teachers, Marshall Swafford Jan 2013

Factors Affecting Teaching Efficacy Of Beginning Secondary Agricultural Education Teachers, Marshall Swafford

LSU Doctoral Dissertations

Teacher efficacy studies in agricultural education have primarily focused on documenting the perceived teaching efficacy of agriculture teachers. A limited number of studies have focused upon the factors that may help shape those efficacy beliefs. Therefore, the primary purpose of this study was to investigate the factors that may contribute to the teaching efficacy beliefs of beginning agriculture education teachers. These factors included perceived collective efficacy, perceived principal support, and perceived teacher preparation program quality. The population for this study included all agriculture teachers in Missouri and Kansas (N=213) who had not completed more than five years teaching agricultural education …


International Adoption Discourse Analysis : Interdisciplinary Approaches To Media Discourse, Youngae Lee Jan 2013

International Adoption Discourse Analysis : Interdisciplinary Approaches To Media Discourse, Youngae Lee

LSU Doctoral Dissertations

This research is focused on media discourse analysis with interdisciplinary perspectives in language, culture, and gender studies. The purpose of this study is to analyze the media discourse of live interpreter-mediated events with distinctive perspectives involving socio-cultural, structural, and linguistic approaches. The discourse used as data is collected from a live Korean TV program called “I Miss That Person” (IMTP). From IMTP, I titled the first clip “Han, Youngwoong’s Discourse” as Data 1 and the second clip “Lee, ChunShik’s Discourse” as Data 2. Two clips of each data can be seen at www.youtube.com. The analysis of the media discourse is …


The Blessing Of The Fleet : Heritage And Identity In Three Gulf Coast Communities, Audriana Hubbard Jan 2013

The Blessing Of The Fleet : Heritage And Identity In Three Gulf Coast Communities, Audriana Hubbard

LSU Master's Theses

Annual Blessing of the Fleet festivals are held throughout communities all along the Gulf Coast; each year boats parade down local waters to receive the blessing of the priest before the opening of the shrimp season. The shrimping industry has a long history in the area and has become intrinsically tied to local individual and community identities. This thesis investigates three festivals held in Chauvin and Morgan City, Louisiana, and Biloxi, Mississippi to understand how the festival is used by participants as a way of negotiating their shrimping identities in a changing socio-economic environment. The tourism and the oil industries …


Investigation Of Best Practices For Maintenance Of Concrete Bridge Railings, Angel Luis Lence Jan 2013

Investigation Of Best Practices For Maintenance Of Concrete Bridge Railings, Angel Luis Lence

LSU Master's Theses

Biodeterioration on concrete surfaces of vertical elements of bridges represents a serious challenge to the highway infrastructure in Louisiana. This investigation aims to document the causes of biodeterioration of concrete surfaces and to document current conventional and state-of-the-art practices implemented to prevent and clean biofilm. A comprehensive literature review of previous research has been carried out in order to determine the cause and mechanisms of the biodeterioration as well as to identify current methods that state DOTs have implemented in order to maintain their bridges and allow them to function in optimal structural and performance conditions. A survey was developed …


Educating For Environmental Justice : Social/Environmental Marginality And The Significance Of Experiences For Environmental Activism And Proenvironmental Behavior, Donovon Keith Ceaser Jan 2013

Educating For Environmental Justice : Social/Environmental Marginality And The Significance Of Experiences For Environmental Activism And Proenvironmental Behavior, Donovon Keith Ceaser

LSU Doctoral Dissertations

Encouraging environmental action and greater proenvironmental behavior has been a main focus of environmental education since its inception. However, many scholars feel that environmental education has largely been unsuccessful at achieving these goals. To invigorate the potential of environmental education, researchers have become more socially critical and started questioning old stances such as addressing the role of action within environmental education and embraced new techniques like examining the role of personal experiences in shaping people sense of identification with the environment. This dissertation is four separate studies that examine how a socially critical environmental education can help produces students who …


Vibrio Parahaemolyticus Interactions With Chitin In Response To Environmental Factors, Vanessa Molina Jan 2013

Vibrio Parahaemolyticus Interactions With Chitin In Response To Environmental Factors, Vanessa Molina

LSU Doctoral Dissertations

Vibrio parahaemolyticus is a naturally occurring chitinoclastic human pathogen that adsorbs to substrates, including chitinous copepods and oysters, as part of its ecology, a phenomenon that is important in its responses to changes in environmental factors such as temperature and salinity. Little is known about acute responses of V. parahaemolyticus when subjected to abrupt environmental changes such as those encountered during postharvest oyster treatments such as icing, exposure to mammalian host conditions, and transport via ballast water. The following in vitro studies investigated V. parahaemolyticus adsorption and gene expression as a function of substrate, temperature, and salinity as a model …


The Baby And Infant Screen For Children With Autism Traits: Age-Based Scoring Procedures, Max Horovitz Jan 2013

The Baby And Infant Screen For Children With Autism Traits: Age-Based Scoring Procedures, Max Horovitz

LSU Doctoral Dissertations

As increasing interest and emphasis has been placed on early intervention for children with Autism Spectrum Disorders (ASD), the need for reliable and valid early assessment techniques has grown significantly. The Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT) is a three-part battery designed to comprehensively assess for ASD in infants and toddlers aged 17 to 37 months. While studies of the measure’s psychometric properties have been promising, the measure’s scoring procedures do not take the child’s age into account. Given the significant amount of development that occurs in the first three years of life, the current paper …


Physical Activity For African American Females : Salience Of Race, Gender-Role, And Exercise Identities, Jasmine M. Hamilton Jan 2013

Physical Activity For African American Females : Salience Of Race, Gender-Role, And Exercise Identities, Jasmine M. Hamilton

LSU Doctoral Dissertations

Social identity theory explores the process of self-identifications based upon perceived shared commonalities with others in order to positively affiliate with group membership and accounts for inter-group and intra-group behaviors (Deaux, 2001; Hogg & Abrams, 1999; Tajfel, 1982). Social identity is also dependent upon environment and situation dynamics (Turner, 1982). African American females are at risk for high levels of physical inactivity. Researchers have suggested the use of frameworks that move investigations beyond assessing social aggregates such as race and gender to understand why this is true. Racial identity, gender-role identity, and exercise identity (derived from social identity theory) provide …


Investigations On The Essentiality Of The Escherichia Coli Deda Membrane Protein Family, Lisa A. Boughner Jan 2013

Investigations On The Essentiality Of The Escherichia Coli Deda Membrane Protein Family, Lisa A. Boughner

LSU Doctoral Dissertations

The DedA protein family is a highly conserved family of membrane proteins, with members present throughout all domains of life: Bacteria, Archaea, and Eukarya. Investigation of the DedA membrane protein family began with the isolation of BC202, an Escherichia coli mutant with in-frame deletions of two DedA proteins of unknown function (YqjA and YghB) that share 61% amino acid identity. BC202 demonstrates temperature sensitivity, inefficient cell division, an altered phospholipid composition, increased expression of extracytoplasmic stress response pathways, as well as an inability to maintain the cell membrane proton motive force (PMF). Additionally, Borrelia burgdorferi has a single DedA homolog …


Characterization Of Epibenthic And Demersal Megafauan At Mississippi Canyon 252 Following The Deepwater Horizon Oil Spill, Marla Maxine Valentine Jan 2013

Characterization Of Epibenthic And Demersal Megafauan At Mississippi Canyon 252 Following The Deepwater Horizon Oil Spill, Marla Maxine Valentine

LSU Master's Theses

Increased demand for new sources of oil and gas has resulted in an expansion of drilling into deeper waters. With this exploratory drilling come increased risks, which were realized on April 20, 2010 when the blow out preventer on the Macondo Well failed, resulting in the release of a large quantity of oil and gas into the Northern Gulf of Mexico from a bathypelagic source. This unprecedented environmental disaster was coined the Deepwater Horizon Oil Spill by the popular news media. In the months that followed the spill, the lack of knowledge about the pre-spill condition of deep-sea communities in …


Gene Set Based Ensemble Methods For Cancer Classification, William Evans Duncan Jan 2013

Gene Set Based Ensemble Methods For Cancer Classification, William Evans Duncan

LSU Doctoral Dissertations

Diagnosis of cancer very often depends on conclusions drawn after both clinical and microscopic examinations of tissues to study the manifestation of the disease in order to place tumors in known categories. One factor which determines the categorization of cancer is the tissue from which the tumor originates. Information gathered from clinical exams may be partial or not completely predictive of a specific category of cancer. Further complicating the problem of categorizing various tumors is that the histological classification of the cancer tissue and description of its course of development may be atypical. Gene expression data gleaned from micro-array analysis …


Rnai-Mediated Antiviral Immunity In Caenorhabditis Elegans, Xunyang Guo Jan 2013

Rnai-Mediated Antiviral Immunity In Caenorhabditis Elegans, Xunyang Guo

LSU Doctoral Dissertations

Viruses are tiny intracellular parasites that often cause devastating diseases on cellular organisms. To suppress viral infection, cellular organisms have evolved a wide spectrum of antiviral defense mechanisms. Antiviral RNA interference (RNAi) is one of the antiviral mechanisms conserved in eukaryotes. During antiviral RNAi, the destruction of invading viral RNAs is mediated by small interfering RNAs derived from the viral replication complex, in the form of double-stranded RNA (dsRNA). Because of its sequence-specific nature, antiviral RNAi can also target host homologous transcripts, for instance leading to disease syndromes in plants. As a counter-defense mechanism, many viruses produce RNAi suppressors that …


Acoustic Biomass Of Fish Associated With An Oil And Gas Platform Before, During, And After "Reefing" It In The Northern Gulf Of Mexico, Grace Elizabeth Harwell Jan 2013

Acoustic Biomass Of Fish Associated With An Oil And Gas Platform Before, During, And After "Reefing" It In The Northern Gulf Of Mexico, Grace Elizabeth Harwell

LSU Master's Theses

With over ~2600 oil and gas platforms (platforms) remaining in the northern Gulf of Mexico (Gulf), the Gulf States have access to one of the most unique fisheries in the world. Because of high abundances of game fishes around platform legs and the popular belief that platforms enhance fish stocks, both Louisiana and Texas have created artificial reef programs based upon the decommissioning of platforms. As oil and gas fields continue to be retired, oil and gas companies may find that “reefing” or toppling a platform may be a more economically viable alternative to complete removal of material. Questions remain …


The Effects Of U.S. Shrimp Imports On The Gulf Of Mexico Dockside Price : A Source Differentiated Mixed Demand Model, Maryam Tabarestani Jan 2013

The Effects Of U.S. Shrimp Imports On The Gulf Of Mexico Dockside Price : A Source Differentiated Mixed Demand Model, Maryam Tabarestani

LSU Doctoral Dissertations

The ever increasing demand for the shrimp products in the 1980s and 1990s caused the volume of shrimp imports to increase. The import of shrimp has had an upward trend, from 847 million pounds in 1997 to 1,636 million pounds in 2010.The imports price has declined since 1997. Along with the decrease in imports price, the U.S. domestic shrimp price has also declined. However, the annual production of shrimp from the Gulf of Mexico has, in the long-run, remained relatively stable. These facts indicate that there is not the same quantity-price relation between the U.S. domestic shrimp market and shrimp …


Fabrication And Characterization Of A Polymeric Nanofluidic Device For Dna Analysis, Jiahao Wu Jan 2013

Fabrication And Characterization Of A Polymeric Nanofluidic Device For Dna Analysis, Jiahao Wu

LSU Doctoral Dissertations

The growing needs for cheaper and faster sequencing of long biopolymers such as DNA and RNA have prompted the development of new technologies. Among the novel techniques for analyzing these biopolymers, an approach using nanochannel based fluidic devices is attractive because it is a label-free, amplification-free, single-molecule method that can be scaled for high-throughput analysis. Despite recent demonstrations of nanochannel based fluidic devices for analyzing physical properties of such biopolymers, most of the devices have been fabricated in inorganic materials such as silicon, silicon nitride and glass using expensive high end nanofabrication techniques such as focused ion beam and electron …


New Strategies For The Synthesis Of Porphyrinoids, Moses Inyanje Ihachi Jan 2013

New Strategies For The Synthesis Of Porphyrinoids, Moses Inyanje Ihachi

LSU Doctoral Dissertations

ABSTRACT Chapter 1 describes the most stable isomer of porphyrin called porphycene. In this chapter photodynamic therapy (PDT) is explained, and the application of porphycenes in PDT is also described. Other biological applications and its uses in catalysis are also summarized here. The general chemical reactions of porphycenes are also explained. Chapter 2 involves the synthesis of pyrroles and bipyrroles. Functionalization of pyrrollic substituents is demonstrated using organometallic coupling reactions like Stille coupling and Grubbs olefin metathesis. The synthesis of divinyl bipyrroles is intended to provide an important precursor to porphycene synthesis via ring closing metathesis using Grubbs catalyst. Chapter …


Vitrification Of Equine Expanded Blastocysts, Fabian Andres Diaz Jan 2013

Vitrification Of Equine Expanded Blastocysts, Fabian Andres Diaz

LSU Master's Theses

The cryopreservation of equine expanded blastocysts (>300 um) has been largely unsuccessful primarily due to the low permeability to cryoprotectants and the large size of the equine embryo. Mechanical alternatives may provide means to overcome the capsule barrier and the relative large embryo size. In this regard, multiple experiments were performed in this study to evaluate different approaches of capsule puncture and blastocoele fluid extraction with the objective to develop a cryopreservation protocol for Day 8 equine expanded blastocysts. In the first experiment, twenty-four Day 8 expanded blastocysts were exposed to standard equine embryo vitrification solutions following one- or …


Dragged Into The Future : How Interent Communications And Media Legitimacy Facilitate Lagging Gender Norms, Skylar C. Gremillion Jan 2013

Dragged Into The Future : How Interent Communications And Media Legitimacy Facilitate Lagging Gender Norms, Skylar C. Gremillion

LSU Doctoral Dissertations

Social interaction is the driving force of human society and extends far beyond one-on-one conversations – it is how we learn about the behavioral expectations, beliefs and symbols of our culture. Sometimes these beliefs and expectations are related to celebrations and events that bring cultures together. Through interaction we learn that we are expected to bring a gift to a birthday party and why we even choose to celebrate birthdays at all. Yet that same framework – which is tied to the way humans categorize each other to make interaction easier – also allows cultures to share biases about different …


Complex Formation And Regulation Of Escherichia Coli Acetyl-Coa Carboxylase, Tyler Craig Broussard Jan 2013

Complex Formation And Regulation Of Escherichia Coli Acetyl-Coa Carboxylase, Tyler Craig Broussard

LSU Doctoral Dissertations

Acetyl-CoA carboxylase is a biotin-dependent, multifunctional enzyme that catalyzes the first committed step in fatty acid synthesis. The Escherichia coli enzyme is composed of a homodimeric biotin carboxylase, biotinylated biotin carboxyl carrier protein (BCCP), and an α2β2 heterotetrameric carboxyltransferase. Catalysis by acetyl-CoA carboxylase proceeds via two half-reactions. In the first half-reaction, biotin carboxylase catalyzes the ATP-dependent carboxylation of biotin, which is covalently attached to BCCP, to form carboxybiotin. In the second half-reaction, carboxyltransferase transfers the carboxyl group from carboxybiotin to acetyl-CoA to form malonyl-CoA. All biotin-dependent carboxylases are proposed to have a two-site ping-pong mechanism where the …


Effects Of Environmental Conditions On Characteristics Of Prescribed Fires And Resprouting Of Hardwoods In Shortleaf Pine-Oak-Hickory Ecosystems Of The United States, Tracy Lynn Hmielowski Jan 2013

Effects Of Environmental Conditions On Characteristics Of Prescribed Fires And Resprouting Of Hardwoods In Shortleaf Pine-Oak-Hickory Ecosystems Of The United States, Tracy Lynn Hmielowski

LSU Doctoral Dissertations

Fire is an essential process for maintaining pine-dominated ecosystems in the southeastern United States. Fire opens space for pine recruitment, consumes fine fuels, stimulates flowering of herbaceous plants, and topkills woody plants. Topkill is the death of the aboveground portion of the plant, which does not necessarily lead to mortality. Most of the woody species in these ecosystems are able to resprout following topkill, sprouting new shoots from meristems at the base of the plant. In the absence of fire, pine-dominated ecosystems transition to closed canopy hardwood forests. Prescribed fires can be applied to mimic the historical fire regime, but …


Social Connectedness Deficits In College Students With Schizotypy, Laura Brown Jan 2013

Social Connectedness Deficits In College Students With Schizotypy, Laura Brown

LSU Doctoral Dissertations

Schizophrenia is a devastating disorder characterized by a variety of bizarre behaviors as well as deficits in neurocognition, social cognition, and functioning. This study focuses on individuals with schizotypy—those with the purported genetic liability for schizophrenia that do not display the full disorder. Prior research has identified potential risk factors for schizophrenia by studying this population, including deficits in social cognition. Studies of social cognition in individuals with schizotypy, however, have yielded inconsistent findings that have failed to fully explain the range of functional deficits seen in these individuals. Social connectedness, in contrast, may be a more useful risk factor …


Microfluidics For The Analysis Of Integral Membrane Proteins: A Top-Down Approach, Katrina Nychole Battle Jan 2013

Microfluidics For The Analysis Of Integral Membrane Proteins: A Top-Down Approach, Katrina Nychole Battle

LSU Doctoral Dissertations

The development of fully automated and high-throughput systems for proteomics is now in demand because of the need to generate new protein-based disease biomarkers. Unfortunately, it is difficult to identify protein biomarkers that are low abundant when in the presence of highly abundant proteins, especially in complex biological samples like serum, cell lysates, and other biological fluids. Membrane proteins, which are in many cases of low abundance compared to cytosolic proteins, have various functions and can provide insight into the state of disease and serve as targets for new drugs making them attractive biomarker candidates. Traditionally, proteins are identified through …


Snap Use Among Older Adults, Jennifer R. Geiger Jan 2013

Snap Use Among Older Adults, Jennifer R. Geiger

LSU Master's Theses

Older adults participate in the Supplemental Nutrition Assistance Program (SNAP) at much lower rates than the general population. Possible explanations for this disparity include stigma, lack of information, and lack of transportation. However, past research focusing on SNAP use among older adults is limited and utilizes age cohorts in their analyses that may not accurately reflect actual age differences in SNAP participation. This study explored four different models of age categorizations as they relate to SNAP participation rates among older adults over 55. Using a sample of 10,116 from the nationally representative Health and Retirement Study (HRS), the research used …