Digital Commons Network^™

Evaluation Of Aflatoxin-Related Products From Ozonated Corn, Alfredo Domingo Prudente, Jr.

LSU Doctoral Dissertations

This study assessed the efficacy of the ozonation process in degrading aflatoxin in corn, and investigated the chemical reaction between aflatoxin and gaseous ozone. Ozonation (12-13 wt%) totally degraded aflatoxin B1 in a model system. Conversion of aflatoxin into polar compounds was observed during ozonolysis of 100 µg aflatoxin B1 in an aqueous environment and in solid form. Seven intermediate reaction products were separated by two-dimensional thin layer chromatography. HPLC analysis of ozonated AFB1 revealed the presence of six major peaks. MALDI-MS analysis detected compounds that have higher molecular weights than AFB1. The dichloromethane fraction contained compounds with molecular ion …

Gas-Phase Formation Of Environmentally Persistent Free Radicals From Thermal Degradation Of Catechol, Hydroquinone, Phenols And Tobacco, Julien Gnonlonfoun Adounkpe

LSU Doctoral Dissertations

Catechol, hydroquinone and Phenol are major constituents of the mainstream tobacco smoke. The toxicity of tobacco has been attributed to the ability of catechol and hydroquinone to undergo endogenous or exogenous redox cycling to form semiquinone type radicals responsible of Reactive Oxygen Species (ROS) formation. ROS such as hydroxyl radicals can cause severe oxidative stress on biological tissues and can provoke severe signaling pathways leading to cardiovascular and pulmonary dysfunctions and carcinogenesis. Given that semiquinone type radicals are organic radicals, characterized by their high instability and reactivity; it is somewhat surprising that they can live long enough mostly when associated …

The Effects Of Cross-Age Mentoring In An Online Collaborative Environment, Gail Lorraine Johnson

LSU Doctoral Dissertations

This mixed method research was designed to examine the effects of cross-age mentoring in an inter-institutional online learning community. The research questions focused on the impact of mentoring on high school students’ confidence in their information seeking skills, perceptions of their information seeking standards, and the application of these standards to an information seeking task. Also of interest was the dialogic interaction between the students at the two sites, the impact of the facilitator on the process, and the university students’ perceptions about their experience. The participants included 26 students (mentees) enrolled in an American history class at a rural …

The Investigation Of Treatment Outcomes For Adults With Chronic Brain Injury Following Intensive Multidisciplinary Treatment, Donna Mineo Fitzgerald-Dejean

LSU Doctoral Dissertations

Although communication sciences and disorders (COMD) research supports intensive treatment for individuals with chronic brain injury, funding to provide these services is limited. This study explored the use of interdepartmental university resources to provide an intensive, multidisciplinary chronic brain injury program. Methodologically, treatment regimes were designed with clinical faculty as practicum experiences for COMD master’s degree students. Subjects with a single onset head injury or cerebral vascular accident greater than one year were recruited to participate in the Intensive Treatment, Weekly Treatment or Control Groups. Pre, Post, and Post-Post Testing were used to measure cognitive-linguistic, quality of life and physical …

Phonemic Awareness And Sight Word Reading In Toddlers, Alicia Tonya Mcinnis

LSU Doctoral Dissertations

This study investigated emerging phonemic awareness skills and printed sight word recognition abilities in two-year-old toddlers using plain text and MorphoPhonic Face words on flash cards. MorphoPhonic Face words were used to determine if this learning process is enhanced when words are iconically represented to show the first sound and the word's meaning (purposefully creating idiosyncratic cues) using pictures superimposed into the letters. Sixteen (16) age-matched toddlers were assigned to alternate treatment groups and received exposure to both printed and MorphoPhonic pictured words three times weekly for six weeks. During each session, children were taught 16 sight words (8 in …

An Investigation Into Fuel Cells And Flow Cytometers Optimal Design, Etim Sunday Udoetok

LSU Doctoral Dissertations

The aim of the fuel cells part of this project was to investigate the performance of Proton Exchange Membrane Fuel Cells and closely related fuel cell types like the Alkaline Fuel Cells and Phosphoric Acid Fuel Cells. The investigation involved understanding the performance of fuel cells, addressing the shortcomings of currently used designs, and finding new methods for improving the performance of fuel cells. CFD was used to study flow channels and information learned from the study was used to design a new and improved flow channel. A prototype of the new design was fabricated, tested and found to perform …

Performing Photographs: Memory, History, And Display, Melanie A. Kitchens

LSU Doctoral Dissertations

In my study, I place concepts and practices of photography and performance in dialogue to enable our understanding of how photographs perform and how performance contains or can contain elements we attribute to photographs. The connection between photography and performance that most intrigues me is how they make memories and when collected or restored in some socially shared way make histories too. My specific aim is to understand how photographs and performance might benefit from each other in how they make and transmit memories and histories. To activate the study, I select and focus on five specific events in which …

Neonatal Respiratory Virus Infection Shapes Pulmonary Function In Adult Mice, Dahui You

LSU Doctoral Dissertations

Respiratory syncytial virus (RSV) and influenza are the two most common causes of acute lower respiratory tract infections in infants. Epidemiological data suggest that both severe RSV and influenza infections during infancy are associated with long-term pulmonary function abnormalities. Despite of the severe burdens of RSV and influenza infections in infants, no efficacious vaccines are available for RSV and the current vaccine strategy for influenza is inconvenient due to the fact that vaccines are made annually based on the prediction of circulating strains in the next season. New strategies in vaccine development have been slow to arrive partly due to …

Fractionation Of The Rice Bran Layer And Quantification Of Vitamin E, Oryzanol, Protein, And Rice Bran Saccharide, Rebecca Schramm, Alicia Abadie, Na Hua, Zhimin Xu, Marybeth Lima

Faculty Publications

Value-added processing with respect to rice milling has traditionally treated the rice bran layer as a homogenous material that contains significant concentrations of high-value components of interest for pharmaceutical and nutraceutical applications. Investigators have shown that high-value components in the rice bran layer vary from differences in kernel-thickness, bran fraction, rice variety, and environmental conditions during the growing season. The objectives of this study were to quantify the amount of rice bran removed at pre-selected milling times and to correlate the amount of rice bran removed at each milling time with the concentration of vitamin E, gamma-oryzanol, rice bran saccharide, …

Shared Parasitoids In A Metacommunity: Indirect Interactions Inhibit Herbivore Membership In Local Communities, James T. Cronin

Faculty Publications

The interaction between species, mediated by a shared natural enemy (i.e., apparent competition), has been the subject of much theoretical and empirical investigation. However, we lack field experiments that assess the importance of apparent competition to metacommunity structure. Here, I conducted a series of field experiments to test whether apparent competition, mediated by shared egg parasitoids (Anagrus nigriventris and A. columbi), occurs between two abundant planthopper species (Delphacodes scolochloa and Prokelisia crocea) of the North American Great Plains. The two planthoppers feed on different plant species within prairie potholes (wet depressions) and, thus, do not interact directly. At the scale …

From Population Sources To Sieves: The Matrix Alters Host-Parasitoid Source-Sink Structure, James T. Cronin

Faculty Publications

Field experiments that examine the impact of immigration, emigration, or landscape structure (e.g., the composition of the matrix) on the source-sink dynamics of fragmented populations are scarce. Here, planthoppers (Prokelisia crocea) and egg parasitoids (Anagrus columbi) were released among host-plant patches that varied in structural (caged, isolated, or in a network of other patches) and functional (mudflat matrix that impedes dispersal vs. brome-grass matrix that facilitates dispersal) connectivity. Planthoppers and parasitoids on caged patches exhibited density-dependent growth rates, achieved high equilibrium densities, and rarely went extinct. Therefore, experimental cordgrass patches were classified as population sources. Because access to immigrants did …

Rediscovering Civil War Classics: Civil War Books Not Yet Written, David Madden

Civil War Book Review

Civil War Books Not Yet Written

A Recombinant Herpes Simplex Virus Type 1 Expressing Two Additional Copies Of Gk Is More Pathogenic Than Wild-Type Virus In Two Different Strains Of Mice, Kevin R. Mott, Guey Chuen Perng, Yanira Osorio, Konstantin G. Kousoulas, Homayon Ghiasi

Faculty Publications

The effect of glycoprotein K (gK) overexpression on herpes simplex virus type 1 (HSV-1) infection in two different strains of mice was evaluated using a recombinant HSV-1 virus that expresses two additional copies of the gK gene in place of the latency-associated transcript (LAT). This mutant virus (HSV-gK 3) expressed higher levels of gK than either the wild-type McKrae virus or the parental dLAT2903 virus both in vitro (in cultured cells) and in vivo (in infected mouse corneas and trigeminal ganglia [TG] of BALB/c and C57BL/6 mice). gK transcripts were detected in the TG of both HSV-gK 3-infected mouse strains …

The Herpes Simplex Virus Ul20 Protein Functions In Glycoprotein K (Gk) Intracellular Transport And Virus-Induced Cell Fusion Are Independent Of Ul20 Functions In Cytoplasmic Virion Envelopment, Jeffrey M. Melancon, Preston A. Fulmer, Konstantin G. Kousoulas

Faculty Publications

The HSV-1 UL20 protein (UL20p) and glycoprotein K (gK) are both important determinants of cytoplasmic virion morphogenesis and virus-induced cell fusion. In this manuscript, we examined the effect of UL20 mutations on the coordinate transport and Trans Golgi Network (TGN) localization of UL20p and gK, virus-induced cell fusion and infectious virus production. Deletion of 18 amino acids from the UL20p carboxyl terminus (UL20 mutant 204t) inhibited intracellular transport and cell-surface expression of both gK and UL20, resulting in accumulation of UL20p and gK in the endoplasmic reticulum (ER) in agreement with the inability of 204t to complement UL20-null virus replication …

Signature-Tagged Mutagenesis Of Edwardsiella Ictaluri Identifies Virulence-Related Genes, Including A Salmonella Pathogenicity Island 2 Class Of Type Iii Secretion Systems, Ronald L. Thune, Denise H. Fernandez, Jennifer L. Benoit, Maria Kelly-Smith, Matthew L. Rogge, Natha J. Booth, Christie A. Landry, Rachel A. Bologna

Faculty Publications

Edwardsieila ictaluri is the leading cause of mortality in channel catfish culture, but little is known about its pathogenesis. The use of signature-tagged mutagenesis in a waterborne infection model resulted in the identification of 50 mutants that were unable to infect/survive in catfish. Nineteen had minitransposon insertions in miscellaneous genes in the chromosome, 10 were in genes that matched to hypothetical proteins, and 13 were in genes that had no significant matches in the NCBI databases. Eight insertions were in genes encoding proteins associated with virulence in other pathogens, including three in genes involved in lipopolysaccharide biosynthesis, three in genes …

Elachista Saccharella (Lepidoptera: Elachistidae), A Leafminer Infesting Sugarcane In Louisiana, W. H. White, T. E. Reagan, C. Carlton, W. Akbar, J. M. Beuzelin

Faculty Publications

The leafminer, Elachista saccharella (Busck) (Lepidoptera: Elachistidae) was found in Louisiana on 12 Jul 2006 and documented as a new distribution record for Louisiana. The leafminer was found in 17 of 20 sugarcane producing parishes surveyed. Although distributed generally throughout the sugarcane growing region, only 11% of the stalks sampled (n = 1600) were infested and 69% of the samples collected were parasitized. The lesions made by the leafminer constituted only 3% of the total leaf area, and were usually detected on older leaves deep within the canopy. For these reasons, it does not appear that E. saccharella will be …

Impact Of Energy Intake, Physical Activity, And Population-Wide Weight Loss On Cardiovascular Disease And Diabetes Mortality In Cuba, 1980-2005, Manuel Franco, Pedro Orduñez, Benjamín Caballero, José A. Tapia Granados, Mariana Lazo, José Luís Bernal, Eliseo Guallar, Richard S. Cooper

Faculty Publications

Cuba's economic crisis of 1989-2000 resulted in reduced energy intake, increased physical activity, and sustained population-wide weight loss. The authors evaluated the possible association of these factors with mortality trends. Data on per capita daily energy intake, physical activity, weight loss, and smoking were systematically retrieved from national and local surveys. National vital statistics from 1980-2005 were used to assess trends in mortality from diabetes, coronary heart disease, stroke, cancer, and all causes. The crisis reduced per capita daily energy intake from 2,899 calories to 1,863 calories. During the crisis period, the proportion of physically active adults increased from 30% …

Cold Seeps And Associated Communities Of The Gulf Of Mexico, Charles Fisher, Harry Roberts, Erik Cordes, Bernie Bernard

Faculty Publications

No abstract provided.

The Barbarous Voice Of Democracy: American Captivity In Barbary And The Multicultural Specter, Jacob Rama Berman

Faculty Publications

No abstract provided.

Conferred Immunity Against The H1n1 Type A Influenza Virus In Madin-Darby Canine Kidney Cells Via Cecropin B Transfection Therapy., Tomasz P. Stryjewski

Honors Capstones

No abstract provided.

Improving Protein Crystal Quality By Selective Removal Of A Ca 2+-Dependent Membrane-Insertion Loop, David B. Neau, Nathaniel C. Gilbert, Sue G. Bartlett, Adam Dassey, Marcia E. Newcomer

Faculty Publications

Lipoxygenases (LOXs) catalyze the regiospecific and stereospecific dioxygenation of polyunsaturated membrane-embedded fatty acids. A Ca 2+-dependent membrane-binding function was localized to the amino-terminal C2-like domain of 8R-lipoxygenase (8R-LOX) from the soft coral Plexaura homomalla. The 3.2 Å crystal structure of 8R-LOX and spectroscopic data suggested that Ca2+ stabilizes two membrane-insertion loops. Analysis of the protein packing contacts in the crystal lattice indicated that the conformation of one of the two loops complicated efforts to improve the resolution of the X-ray data. A deletion mutant of 8R-LOX in which the corresponding membrane-insertion loop is absent (Δ41-45:GSLOX) was engineered. Removal of the …

Role Of Adiponectin And Inflammation In Insulin Resistance Of Mc3r And Mc4r Knockout Mice, James L. Trevaskis, Barbara Gawronska-Kozak, Gregory M. Sutton, Michele Mcneil, Jacqueline M. Stephens, Steven R. Smith, Andrew A. Butler

Faculty Publications

Objective: To investigate the involvement of hypoadiponectinemia and inflammation in coupling obesity to insulin resistance in melanocortin-3 receptor and melanocortin-4 receptor knockout (KO) mice (Mc3/4rKO). Research Methods and Procedures: Sera and tissue were collected from 6-month-old Mc3rKO, Mc4rKO, and wild-type C57BL6J litter mates maintained on low-fat diet or exposed to high-fat diet (HFD) for 1 or 3 months. Inflammation was assessed by both real-time polymerase chain reaction analysis of macrophage-specific gene expression and immunohistochemistry. Results: Mc4rKO exhibited hypoadiponectinemia, exacerbated by HFD and obesity, previously reported in murine models of obesity. Mc4r deficiency was also associated with high levels of macrophage …

Calcium-Dependent Fast Depolarizing Afterpotentials In Vasopressin Neurons In The Rat Supraoptic Nucleus, Ryoichi Teruyama, William E. Armstrong

Faculty Publications

Oxytocin (OT) and vasopressin (VP) synthesizing magnocellular cells (MNCs) in the supraoptic nucleus (SON) display distinct firing patterns during the physiological demands for these hormones. Depolarizing afterpotentials (DAPs) in these neurons are involved in controlling phasic bursting in VP neurons. Our whole cell recordings demonstrated a Cs+-resistant fast DAP (fDAP; decay tau = ∼200 ms), which has not been previously reported, in addition to the well-known Cs+-sensitive slower DAP (sDAP; decay tau = ∼2 s). Immunoidentification of recorded neurons revealed that all VP neurons, but only 20% of OT neurons, expressed the fDAP. The activation of the fDAP required influx …

Sound Production And Spectral Hearing Sensitivity In The Hawaiian Sergeant Damselfish, Abudefduf Abdominalis, Karen P. Maruska, Kelly S. Boyle, Laura R. Dewan, Timothy C. Tricas

Faculty Publications

Sounds provide important signals for inter- and intraspecific communication in fishes, but few studies examine fish acoustic behavior in the context of coevolution of sound production and hearing ability within a species. This study characterizes the acoustic behavior in a reproductive population of the Hawaiian sergeant fish, Abudefduf abdominalis, and compares acoustic features to hearing ability, measured by the auditory evoked potential (AEP) technique. Sergeant fish produce sounds at close distances to the intended receiver (≤1-2 body lengths), with different pulse characteristics that are associated primarily with aggression, nest preparation and courtship-female-visit behaviors. Energy peaks of all sounds were between …

Characterization Of Polymorphic Microsatellite Loci For The Invasive Monk Parakeet (Myiopsitta Monachus), M. A. Russello, V. Saranathan, S. Buhrman-Deever, J. Eberhard, A. Caccone

Faculty Publications

Microsatellite loci were characterized for the monk parakeet (Myiopsitta monachus) from a GTn-enriched genomic library. Twelve of 14 microsatellite loci were polymorphic, averaging 6.7 alleles per locus across the 20 individuals genotyped. Mean expected heterozygosity was 0.72, with locus-specific values ranging from 0.53 to 0.90. An equally high multilocus probability of identity (2.48 × 10-12) was revealed for this set of loci. In addition, all 12 loci were demonstrated to cross-amplify to varying extents within three additional parrot genera suggesting their potential utility for population-level studies in a broad range of Neotropical psittacines. © 2007 The Authors.

The Chlamydomonas Genome Reveals The Evolution Of Key Animal And Plant Functions, Sabeeha S. Merchant, Simon E. Prochnik, Olivier Vallon, Elizabeth H. Harris, Steven J. Karpowicz, George B. Witman, Astrid Terry, Asaf Salamov, Lillian K. Fritz-Laylin, Laurence Maréchal-Drouard, Wallace F. Marshall, Liang Hu Qu, David R. Nelson, Anton A. Sanderfoot, Martin H. Spalding, Vladimir V. Kapitonov, Qinghu Ren, Patrick Ferris, Erika Lindquist, Harris Shapiro, Susan M. Lucas, Jane Grimwood, Jeremy Schmutz, Igor V. Grigoriev, Daniel S. Rokhsar, Arthur R. Grossman, Pierre Cardol, Heriberto Cerutti, Guillaume Chanfreau, Chun Long Chen, Valérie Cognat, Martin T. Croft, Rachel Dent

Faculty Publications

Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, …

Habitat Fragmentation, Variable Edge Effects, And The Landscape-Divergence Hypothesis, William F. Laurance, Henrique E.M. Nascimento, Susan G. Laurance, Ana Andrade, Robert M. Ewers, Kyle E. Harms, Regina C.C. Luizão, José E. Ribeiro

Faculty Publications

Edge effects are major drivers of change in many fragmented landscapes, but are often highly variable in space and time. Here we assess variability in edge effects altering Amazon forest dynamics, plant community composition, invading species, and carbon storage, in the world's largest and longest-running experimental study of habitat fragmentation. Despite detailed knowledge of local landscape conditions, spatial variability in edge effects was only partially foreseeable: relatively predictable effects were caused by the differing proximity of plots to forest edge and varying matrix vegetation, but windstorms generated much random variability. Temporal variability in edge phenomena was also only partially predictable: …

Hypoxia In The Northern Gulf Of Mexico: Does The Science Support The Plan To Reduce, Mitigate, And Control Hypoxia?, Nancy N. Rabalais, R. Eugene Turner, B.K. Sen Gupta, D. F. Boesch, P. Chapman, M. C. Murrell

Faculty Publications

We update and reevaluate the scientific information on the distribution, history, and causes of continental shelf hypoxia that supports the 2001 Action Plan for Reducing, Mitigating, and Controlling Hypoxia in the Northern Gulf of Mexico (Mississippi River/Gulf of Mexico Watershed Nutrient Task Force 2001), incorporating data, publications, and research results produced since the 1999 integrated assessment. The metric of mid-summer hypoxic area on the Louisiana-Texas shelf is an adequate and suitable measure for continued efforts to reduce nutrients loads from the Mississippi River and hypoxia in the northern Gulf of Mexico as outlined in the Action Plan. More frequent measurements …

Louisiana Agriculture Fall, 2007, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

Split Luciferase Complementation Assay To Study Protein-Protein Interactions In Arabidopsis Protoplasts, Yukichi Fujikawa, Naohiro Kato

Faculty Publications

We developed a split luciferase complementation assay to study protein-protein interactions in Arabidopsis protoplasts. In this assay, the N- and C-terminal fragments of Renilla reniforms luciferase are translationally fused to bait and prey proteins, respectively. When the proteins interact, split luciferase becomes activated and emits luminescence that can be measured by a microplate luminometer. Split luciferase activity was measured by first transforming protoplasts with a DNA vector in a 96-well plate. DNA vector expressing both bait and prey genes was constructed through two independent in vitro DNA recombinant reactions, Gateway and Cre-loxP. As proof of concept, we detected the protein-protein …