Digital Commons Network^™

The Effects Of Stat Activators In The Crosstalk Of Gp130 Cytokines In Adipocytes, Ursula Antoinette White

LSU Doctoral Dissertations

Obesity is characterized by an overabundance of fat cells, or adipocytes, and is currently a global epidemic. Adipocytes store energy, respond to insulin, and participate in diverse endocrine signaling pathways by secreting adipokines. Obesity leads to the dysregulation of adipocyte function, which could lead to numerous metabolic diseases, such as Type II diabetes. Understanding the mechanisms that regulate adipocyte development and involvement in endocrine signaling will lead to a greater understanding of the importance of fat metabolism in full-body health. Many lines of evidence demonstrate the importance of various transcription factors in regulating adipogenic processes, and one of which is …

Nitric Oxide Cytotoxicity And Functions Of Iron-Sulfur Enzymes In Escherichia Coli, Binbin Ren

LSU Doctoral Dissertations

Iron-sulfur proteins are ubiquitous in biological processes. Here we report that NO, a physiological free radical, can effectively inhibit cell growth of Escherichia coli in minimal medium under anaerobic growth conditions. Fractionation of the cell extracts obtained from NO-exposed cells shows a broad distribution of the protein-bound dinitrosyl-iron complexes (DNICs) formed by NO. On the other hand, the cell growth of E. coli can be restored when NO-exposed cells are either supplemented with the branched-chain amino acids (BCAAs) anaerobically or returned to aerobic growth conditions. It turns out that dihydroxyacid dehydratase (IlvD), an iron-sulfur enzyme essential for the BCAAs biosynthesis, …

The Role Of Climate Variability And Riverine Pulsing In The Community Dynamics Of Estuarine Nekton In Breton Sound, Louisiana, Bryan Patrick Piazza

LSU Doctoral Dissertations

Climate controls biotic community composition at multiple spatiotemporal scales through variability in environmental control mechanisms (assembly filters). This research investigated the role of climate variability in the community dynamics of estuarine nekton in Breton Sound estuary, Louisiana, and, specifically the effects of El Niño Southern Oscillation (ENSO), freshwater discharge, and a tropical cyclone. A teleconnection was found between ENSO and juvenile brown shrimp (Farfantepenaeus aztecus) abundance in Breton Sound from 1988 – 2007. ENSO affected winter weather conditions (air pressure, temperature and precipitation), and spring brown shrimp abundance in Breton Sound. Juvenile brown shrimp abundance lagged ENSO by …

Apolipoprotein Status And Cognitive Functioning In Adulthood: Role Of Physical Health And Social Network Characteristics, Jennifer Lee Silva

LSU Doctoral Dissertations

This study examined the relationships among cognitive function, physical health, social network characteristics, and apolipoprotein (APOE) genotype in participants from the Louisiana Healthy Aging Study. Prior literature has shown that the ε4 allele of APOE is associated with cognitive deficits (Wisdom, Callahan, & Hawkins, 2009). This study failed to find any relation between APOE genotype (ε4 carrier vs. non-carrier) and cognitive ability after controlling for age and education level. Tests for physical health mediation and social network moderation did not alter the ε4/cognition null results. This finding conflicts with prior research suggesting that physical activity and health modify the association …

Intellectual Ability In Children With Anxiety: A Replication And Exploration Of The Differences, Melissa S. Munson

LSU Master's Theses

The purpose of this study was to examine the effect of anxiety on the intellectual functioning of children. Specifically, the current researchers sought to replicate previous findings that children with higher levels of anxiety have significantly lower scores on tests of intelligence. A second goal was to examine possible reasons for these deficits, including possible deficits in working memory and/or attention. Participants were divided into two groups with high and low anxiety, based on a self-report measure, though none of the children reported clinically problematic anxiety. The participants were 19 children (10 males, 9 females) who were recruited from the …

The Isolation And Characterization Of Bovine Adult Derived Adipose Stem Cells For The Use In Nuclear Transfer, Alicia A. Picou

LSU Master's Theses

Since the cloning of Dolly there has been little change in the efficiency of nuclear transfer (NT). Research is beginning to investigate the characteristics of donor cells. Adiposetissue is an abundant source of adult-derived cells that have displayed “stemness” in-vitro(Gimble et al., 2003). The overall goal of this research was to define the in-vitro characteristicsof bovine adipose-derived adult stem cells (ADAS) for the use in NT. Isolation methods weredetermined by a 3 x 3 factorial design. 1 g of subcutaneous fat was collected and subjected to0.10%, 0.25% or 0.50% collagenase type I solution for 1, 2 and 3 h. Nucleated …

Advocacy Groups In The Wake Of Hurricane Katrina: Who Shapes Coverage Of Wetlands Loss, Paul Harang

LSU Master's Theses

Louisiana’s coastal wetlands provide a habitat for diverse wildlife, recreational opportunities for Louisiana residents and tourists, and an important natural buffer between communities and powerful hurricanes. Because they are disappearing at a rapid rate, coastal wetlands issues have been prominent in south Louisiana for decades. The catastrophic hurricanes of 2005 and 2008 have given the discussion an increased sense of urgency. Through this paper, I explore coverage of wetlands loss in local south Louisiana daily newspapers. Specifically, I try to determine how these papers frame the issue and illuminate how sources present in these stories participate in the construction of …

Effects Of Network Capital And Social Support On Mental Health By Race And Class, Claire Norris

LSU Doctoral Dissertations

This study investigates race and class differences in the stress-support-distress process. Incorporating the social support strand of network analysis in the stress-support-distress model allows social support theorists to understand better what network sectors enhance/restrict access to such resources as social support and, in turn, affect such outcomes as mental health. I used data collected in a 2003 study of residents in Orleans Parish, Louisiana, to construct measures used in my analyses. Using independent samples t-test and ordinary least squares regressions, I addressed five general research questions: (1) whether and how there are variations in network capital forms – the structure …

Dispositional Influences On The Intent To Transfer Learning: A Test Of A Structural Equation Model, Bogdan Vladimirovich Yamkovenko

LSU Doctoral Dissertations

The transfer research has evolved to a significant body of works during the last two decades. Many relationships however remain unexplored and unexplained. Among these are dispositional characteristics, which are rarely studied in combination with transfer because of difficulties and inconsistencies in measurement. In addition dispositional characteristic are so numerous that it is often difficult to identify a set of such variable that explain the most variance in transfer of training. This study explores the hypothesized relationship between dimensions of the Five Factor model of personality, goal orientation, self-efficacy and intent to transfer training on the job. Most research articles …

Nestablishing Soil Compaction Thresholds For The M1a1 Abrams Tank At Camp Minden, Louisiana, Michael Ray Lindsey

LSU Doctoral Dissertations

Soil compaction is a primary impediment to vegetation regeneration on military land used for M1A1 Abrams tank training. As such, there is a need to identify soil compaction thresholds and develop guidelines with which military range managers can determine appropriate timing and intensity of training exercises using the 63-ton M1A1 tank. A study was initiated at the Camp Minden Louisiana Training Site (CMTS) to develop guidelines which will allow for maximum utilization of the land resource with minimum degradation. The study was designed to evaluate soil moisture content and traffic rates as experimental variables using a replicated 3 x 3 …

Bottom Boundary Layer Physics And Sediment Transport Along A Transgressive Sand Body, Ship Shoal, South-Central Louisiana: Implications For Fluvial Sediments And Winter Storms, Daijiro Kobashi

LSU Doctoral Dissertations

Ship Shoal, a shore-parallel sand body, was recently recognized as having a unique physical and biological environment and also as a potential sand resource for coastal restoration in coastal Louisiana. Little is known regarding such dynamics, in concert with fluvial sediments and winter storms, influenced in unique ecosystems, and likely in future potential sand mining. This dissertation addresses such the morphodynamics and sedimentary processes and their implications for the mining from the shoal using field measurements and numerical modeling studies. During the winter-spring season, fluvial sediment plumes shifted from the prevailing west to southeast during the post-frontal phases, resulted in …

Under Construction: Recollecting The Museum Of The Moving Image, Andr&Eacutee Elise Comiskey Betancourt

LSU Doctoral Dissertations

On February 27, 2008 the Museum of the Moving Image launched its $65 million renovation and expansion with a digital groundbreaking. Since opening its doors in Astoria, New York in 1988, the museum, originally devoted to film and television, has embraced digital media. From its “Hollywood East” Astoria Studio historic landmark site to its popular website, the Museum of the Moving Image provides a unique setting for studying the museumification of moving image culture, particularly the production and consumption of moving images. In response to the Museum of the Moving Image’s domestication of moving image culture in its core exhibition, …

Collpas As Activity Hotspots For Frugivorous Bats (Stenodermatinae) In The Peruvian Amazon: Underlying Mechanisms And Conservation Implications, Adriana Bravo Ordonez

LSU Doctoral Dissertations

In western Amazonia, large numbers of frugivorous bats regularly visit natural forest clearings known locally as collpas (also called clay licks or mineral licks). Bats arrive at collpas to drink water that has accumulated in depressions created by larger mammals that consume soil. Although collpa visitation by bats appears relatively common in western Amazonia, little is known about its causes and its ecological implications. In this dissertation I describe general and seasonal patterns of collpa visitation by frugivorous bats in the Peruvian Amazon, and I investigate potential explanations for this unique behavior. Regardless of season, collpas seem to be activity …

Amyloid Aggregation-Mitigating Peptides As Potential Alzheimer's Drugs, Cyrus Kipkurui Bett

LSU Doctoral Dissertations

Neuronal cytotoxicity observed in Alzheimer¡¦s disease (AD) is linked to the aggregation of £]-amyloid peptide (A£]) into toxic forms. Increasing evidence points to oligomeric species as the neurotoxic species compared to fibrils; disruption or inhibition of A£]ƒnself-assembly into oligomeric or fibrillar forms remains a viable therapeutic strategy to reduce A£] neurotoxicity. Amyloid aggregation mitigating peptides (AAMPs) were designed based on the A£]ƒn¡§hydrophobic core¡¨ A£]17-20, with C£\,£\-disubstituted amino acidsƒnƒv£\£\AAs) added into this core as disrupting agents. The number, distribution, and side chain functionality of £\£\AAs incorporated into the mitigator sequence was found influences the resultant aggregate morphology as indicated by ex-situ …

Multiple Dataset Visualization (Mdv) Framework For Scalar Volume Data, Gaurav Khanduja

LSU Doctoral Dissertations

Many applications require comparative analysis of multiple datasets representing different samples, conditions, time instants, or views in order to develop a better understanding of the scientific problem/system under consideration. One effective approach for such analysis is visualization of the data. In this PhD thesis, we propose an innovative multiple dataset visualization (MDV) approach in which two or more datasets of a given type are rendered concurrently in the same visualization. MDV is an important concept for the cases where it is not possible to make an inference based on one dataset, and comparisons between many datasets are required to reveal …

Achiral, Chiral, And Protein Separations With Molecular Micelles Using Chromatographic Techniques, Candace Ayanna Luces

LSU Doctoral Dissertations

In this dissertation, several chromatographic techniques were developed for separation of proteins as well as achiral and chiral compounds. Firstly, polyelectrolyte multilayer (PEM) coatings were used to separate chiral analytes and proteins of pharmaceutical and biomedical interests. Coating polymers used in PEM coatings are instrumental in analyte separation. Therefore, the effect of changing four different cationic polymers, (poly-L-lysine, poly-L-ornithine, poly-L-lysine-serine, and poly-L-glutamic acid-lysine) and three anionic polymers (sodium poly (N-undecanoyl-L-leucyl-alaninate) (poly-L-SULA), sodium poly (N-undecanoyl-L-leucyl-valinate) (poly-L-SULV) and sodium poly (undecylenic sulfate) (poly-SUS)) were investigated. The simultaneous effects of cationic polymer concentration, number of bilayers, temperature, applied voltage, and pH of the …

Computational Studies On Fatty Acid Synthesis: From Mechanisms To Drug Design, Matthew Edward Mckenzie

LSU Doctoral Dissertations

The first committed steps of the Fatty Acid synthesis pathway involves the de/carboxylation reactions of biotin. By understanding this step, potential novel antimicrobial agents could be discovered. The current tools of drug discovery can only help the research in finding and modifying potential hits. Finding a lead candidate from these programs are often equated to finding a needle in a haystack, which is due to the many assumptions used in molecular docking. The fundamental reaction kinetics can not be described by these techniques and a detailed study of the decarboxylation reaction is investigated using ab initio molecular dynamics. In this …

Matrix Metalloproteinases In The Equine Systemic Inflammatory Response: Implications For Equine Laminitis, Lee Ann Fugler

LSU Doctoral Dissertations

Laminitis is a crippling and often life-threatening disease of the equine foot. Soft tissue damage characteristic of this disease has been associated with increased MMP activity. Therefore, it seems likely that MMPIs could be potential therapeutic agents for laminitis. Further characterization of equine MMPs and evaluation of the effectiveness of MMPIs in the horse are needed. Equine MMP-9 was harvested from neutrophils, purified by affinity chromatography, and evaluated using western blotting and gelatin zymography. The Biotrak MMP-9 Activity Assay was evaluated for use with equine samples using equine neutrophil MMP-9 as a standard, and was determined to have insufficient sensitivity …

Particle-Chemical Interactions And Environmental Chemodynamics Of Fine And Ultrafine Particles In A Natural Disaster Scenario, Nicholas A. Ashley

LSU Doctoral Dissertations

The interactions of fine and ultrafine particles with chemicals play a dominant role in determining the mobility and availability of pollutants in the environment. Fine particles in sediments can sequester chemicals from the water column, and release volatile and semi-volatile organic compounds to the gas phase upon exposure to air. Ultrafine particles which are photoreactive can degrade these vapor-phase contaminants, and may transform the molecules into species which are more toxic or hazardous than the parent. As the widespread, commercial use of ultrafine particles becomes more common, understanding the chemodynamics of these particles and their interactions with chemicals in the …

Response Of Selected Warm-Season Turfgrasses And Ornamental Monocots To Short-Term, High Concentration, Ozone Fumigation, Lou Ann Mcknight

LSU Doctoral Dissertations

Ozone (O3), one of the most powerful oxidants known, is phytotoxic at high levels in the troposphere, or ground-level. Effects of acute ozone exposure for two consecutive days was examined on Bermudagrass (Cynodon dactylon), centipedegrass (Eremochloa ophiuroides), zoysiagrass (Zoysia japonica), St. Augustinegrass (Stenotaphrum secundatum), Liriope muscari ‘Big Blue’, Liriope muscari ‘Aztec’, and Ophiopogon japonicus. Zoysiagrass, St. Augustinegrass, Liriope muscari ‘Big Blue’ were used in the second study based on the differential responses found in the study. Ozone induced severe visual damage to St. Augustinegrass with symptoms appearing as chlorotic streaks. St. Augustinegrass and Liriope muscari had a significant reduction in …

Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, And Application To Catalysis, Hongyi Wu

LSU Doctoral Dissertations

The research in this dissertation focuses on the synthesis of size-controlled metal oxide nanoclusters (< 10 nm) on amorphous silica and their catalytic performance in thermal degradation of chlorinated benzenes with regard to the cluster size effect. Furthermore, with the concern that metal can condense as the nano-size nuclei core for particle growth in combustion process, a flow reactor was built to investigate the effect of metal oxide nanoparticles on the formation of soot in fuel-rich combustion. The synthesis of copper oxide nanoclusters was carried by calcination of silica impregnated with dendrimer-metal complexes. The 4th generation poly(propylene imine) dendrimer DAB-Am32 was used in this template-based method. The sizes of copper oxide nanoclusters were exquisitely controlled in the range of 1-5 nm with narrow size distribution by changing the stoichiometric ratio of metal ion to the terminal primary amines of dendrimer, the equivalent metal oxide loading on surface, and the impregnation procedure. XANES and XPS studies revealed that CuO was the dominant component of copper oxide nanoclusters. This method was also experimentally proven to be valid in the preparation of other metal oxide nanoparticles, e.g., Ni and Fe, and with other oxide substrates, e.g., titanium oxide. Chlorinated benzenes were selected as the model compound for studying the activity of metal (Cu and Fe) oxide catalysts with regard to their cluster sizes. Compared to the surrogate of coarse metal oxide samples, which was prepared by incipient wetness method, their nanosize analogues showed superior catalytic activity on the conversion of chlorinated benzenes under both pyrolytic and oxidative thermal condition. Furthermore, such catalytic size effect was also observed on the selectivity of products yields. Sooting combustion was performed using a two-zone flow reactor with precise control on experimental parameters. Gas suspended metal oxide nanoparticles were generated by burning off the organic backbone of the dendrimer-metal complexes in zone 1 and immediately transferred to zone 2, where the hydrocarbon combustion occurred. TEM results of the particulate sample collected at the outlet of reactor indicated that metal oxide nanoparticles promoted soot formation. GC/MS analysis of the extracted organic materials from soot samples suggested the formation of PAH was also promoted by metal addition as well.

The Effects Of Geomorphology And Primary Productivity On Neotropical Leaf Litter Herpetofauna: Implications For Amazonian Rainforest Conservation, Jessica L. Deichmann

LSU Doctoral Dissertations

The Amazon rainforest encompasses over one billion acres of South America and sustains remarkable biodiversity. Despite the large body of research stemming from this region, little is known about the effects of geomorphology and primary productivity on the fauna of Amazonia, and on reptiles and amphibians in particular. In my dissertation, I examine differences in the abundance, biomass and species richness of secondary consumers in the leaf litter herpetofauna communities on young and ancient soils. Herein, I develop methods to utilize existing data sets and museum collections in new studies involving community biomass. I found that, although the process of …

Studies On The Effect Of Natural Organic Matter And Hydration On The Sorption And Desorption Of Trifluorinated Pesticides, Charisma Vinarao Lattao

LSU Doctoral Dissertations

This work was done in order to deepen our molecular level understanding of how soil organic matter (SOM) is assembled in a whole soil and to provide further insight on the effect of SOM assembly on the uptake and release of hydrophobic organic compounds. Various techniques, including ultraviolet absorbance, fluorescence, and total carbon analysis, demonstrate that hydration/solvation of SOM is kinetically controlled. Initial wetting of a soil releases the hydrophobic moieties that are located at the outer surface of SOM, and longer wetting times exfoliate more hydrophobic quinone type moieties that are present in the middle layer, which in turn …

Phytochemical Analyses Of Bioactive Compounds In The Roots Of Cassia Alata Linn And The Anti-Angiogenic Evaluation Of Rhein As A Therapeutic Agent Against Breast Cancer Cells, Vivian Esther Fernand

LSU Doctoral Dissertations

The research presented in this dissertation includes the novel phytochemical analysis of root extracts of Cassia alata L. and the anti-angiogenic evaluation of rhein in the treatment of breast cancer. To conduct these studies a combination of analytical techniques were employed, namely, chromatographic, spectroscopic, and bioanalytical. The first part of this research is focused on the phytochemical analysis of C. alata root extracts. A high performance liquid chromatography method was developed and validated for the determination of six phenolic compounds in the root extracts. The investigated compounds were identified by their ultraviolet spectra. Additionally, the presence of these phenolics was …

Antiviral Chemotherapeutic Agents Against Equine Herpesvirus Type 1: The Mechanism Of Antiviral Effects Of Porphyrin Derivatives, Galena V. Rybachuk

LSU Doctoral Dissertations

Equine Herpesvirus-1 (EHV-1) is an important ubiquitous enzootic equine pathogen, causing significant economic losses to the horse industry. Despite extensive vaccination protocols, EHV-1 continues to be a major cause of epidemic abortion, perinatal mortality, respiratory disease and neurologic disease. EHV-1 infections are usually dealt with by using management practices that limit spread of the disease and secondary complications, providing symptomatic relief to infected horses, but no specific treatment is available. New therapeutic or virucidal agents could have great utility in slowing both the progression and spread of the disease in an epidemic situation. A number of porphyrins and their derivatives …

Investigations Of Chlamydomonas Reinhardtii Ergosterol Biosynthesis, Kristy Marie Brumfield

LSU Doctoral Dissertations

Ergosterol is the major sterol found in the membranes of Chlamydomonas reinhardtii. While past studies have identified some ergosterol mutants in C. reinhardtii, very little is known about sterol biosynthesis pathways in this species. With the elucidation of the Chlamydomonas genome, bioinformatics analysis has allowed us to determine potential genes involved in ergosterol biosynthesis. With this knowledge, a working model of the pathway was designed for future analysis. Several of the ergosterol biosynthetic genes were analyzed in respect to their role and involvement in flagellar regeneration. These genes were upregulated during the regrowth of the flagella. Also Chlamydomonas strains lacking …

Functional Implications Of The Neuromuscular Transform In Decapod Crustacean Locomotion, Richard Burkett Dewell

LSU Doctoral Dissertations

All animals face the same basic challenges in controling movement through their environment. The central nervous system must activate and effectively control muscle fibers capable of accomplishing the behavior. For multi functional muscles, an array of muscle fiber types must be selectively activated based on the behavioral task. In arthropods that have few motor neurons, it is not understod how the nervous system accomplishes this selective activation. If the selection cannot be achieved by recruitment of different motor neurons, then it most likely results from careful adjustment to the firing patterns of the motor neurons. I used the neuromuscular system …

Parallel Cloth Simulation Using Openmp And Cuda, Gillian David Sims

LSU Doctoral Dissertations

The widespread availability of parallel computing architectures has lead to research regarding algorithms and techniques that best exploit available parallelism. In addition to the CPU parallelism available; the GPU has emerged as a parallel computational device. The goal of this study was to explore the combined use of CPU and GPU parallelism by developing a hybrid parallel CPU/GPU cloth simulation application. In order to evaluate the benefits of the hybrid approach, the application was first developed in sequential CPU form, followed by a parallel CPU form. The application uses Backward Euler implicit time integration to solve the differential equations of …

Cbod₅ Treatment And Nitrogen Transformations Of The Marshland Upwelling System In Intermediate And Saltwater Marshes, Lorna Anne Putnam

LSU Doctoral Dissertations

The marshland upwelling system (MUS) was designed to treat domestic wastewater from coastal dwellings where conventional methods are inadequate due to high water tables, poor hydraulic soil conditions, anaerobic soils, and saline groundwater. Currently there is no adequate treatment system available and coastal dwellings are contributing to water quality problems. This study focused on determining the treatment effectiveness of the MUS for organic matter and understanding the specific processes involved in nitrogen treatment.

The treatment of organic matter, measured as five-day carbonaceous biological oxygen demand (CBOD₅), was effective in field tests for both saltwater and intermediate marshes. Global …

The Effects Of Visual Representations On Teacher Training Of Phonological Awareness Principles, Rachel Kennedy Powell

LSU Doctoral Dissertations

Teachers are now being held to high accountability standards in reading instruction, yet studies show that teachers lack adequate knowledge in reading and phonological awareness principles (Moats, 1994, 2009; Spencer, Schuele, Guillot, & Lee, 2008). The purpose of this study was to determine the effects of visual representations of letter/sound production (i.e., Phonic Faces, Norris, 2001) on improving teacher knowledge of phonological awareness principles, and to determine if there is a concomitant improvement in phonological awareness and reading acquisition for children in those classrooms. Seventeen kindergarten teachers from a Mississippi school were pretested on phonological awareness principles, then divided into …