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Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda Jan 2013

Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda

LSU Master's Theses

The main objective of this work is to study the liposomal uptake of silver and old nanoparticles. Liposomes were prepared in Heating Method. The phospholipids used to prepare liposomes are 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (16:0 PC); 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (16:0 PG); 1,2-distearoyl-sn-glycero-3-phosphocholine (18:0 PC); 1,2-distearoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (18:0 PG).Four different combinations of phospholipids were used to prepare liposomes. In all four combinations two types of phospholipids were used. The liposomes were incubated for 30 minute, 1 hour, 2 hour and 4 hour with silver and gold nanoparticles in streptavidin coated glass slide. All four liposomal formulations had a biotinylated lipid (1-oleoyl-2-[12-biotinyl(aminododecanoyl)]-sn-glycero-3-phosphocholine) which has a string …

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Biofilter Treatment Of Gas Phase Β-Caryophyllene At Elevated Temperature, Yiying Yue Jan 2013

Biofilter Treatment Of Gas Phase Β-Caryophyllene At Elevated Temperature, Yiying Yue

LSU Master's Theses

Industrial wood processing operations generate a variety of gaseous emissions containing volatile organic compounds (VOCs). One of the VOCs emitted from the processing of coniferous softwood tree species is β-caryophyllene, a naturally occurring sesquiterpene of environmental concern. One approach that may be attractive for treating gaseous emissions of β-caryophyllene from wood processing operations is the use of fixed-film processes commonly referred to as biofiltration. Previously, it was established that β-caryophyllene can be successfully treated via biofiltration at temperatures in the mesophilic range. Many gaseous emissions from industrial wood processing operations, however, are higher in temperature than those employed in the …

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Effect Of Atmospheric Boundary Layer Conditions On Agricultural Spray Drift, William Tollefson Jan 2013

Effect Of Atmospheric Boundary Layer Conditions On Agricultural Spray Drift, William Tollefson

LSU Master's Theses

Drift of pesticides can be a significant health hazard, particularly in areas where agricultural land is adjacent to a school, retirement home, or other populated area. Off-target drift of pesticides depends on many atmospheric variables, both mechanical and thermal. While non-atmospheric variables, such as applicator nozzle size, height of application, and particle size, can be controlled by the applicator to reduce drift potential, understanding how atmospheric conditions set a framework for drift potential enables applicators to choose to spray when the weather conditions would minimize drift. Specifically, atmospheric stability plays an important role in the near-ground concentration of sprays downwind …

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Metacognition And Its Effect On Learning High School Calculus, Bonnie Sue Bergstresser Jan 2013

Metacognition And Its Effect On Learning High School Calculus, Bonnie Sue Bergstresser

LSU Master's Theses

The following paper discusses the effect of metacognitive training sessions on students’ calculus retention. Students in two high school classes participated. The students in both classes were then given lessons on a chapter without metacognitive training and lessons on a subsequent chapter with training in a set of metacognitive skills. After the latter chapter students scored higher on a post-test and expressed desire to incorporate the skills they learned into their other classes.

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Oxidative Stress Based Response Of A Transcriptional Regulator, Ohrr, From Burkholderia Thailandensis, Anuja Pande Jan 2013

Oxidative Stress Based Response Of A Transcriptional Regulator, Ohrr, From Burkholderia Thailandensis, Anuja Pande

LSU Master's Theses

Being ubiquitous in nature, bacteria are often faced by environmental stresses. The predominant form of stress being the ‘oxidative’ one, prevalent during host invasion. As one of the host’s protective mechanisms, bacteria are bombarded by various kinds of organic and inorganic oxidants. Several bacterial antioxidant systems have been studied and characterized to be potent enough to scavenge such host-derived reactive oxygen species, aiding in bacterial survival within the host. Broadly, the antioxidant scavengers are categorized into those that are specific for inorganic or organic oxidants. Although a lot has been studied about the former, the latter still remains uncharacterized in …

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The Effects Of Chronic And Acute Exercise Modalities On Substrate Utilization And Plasma Adiponectin Concentration, Greggory Ryan Davis Jan 2013

The Effects Of Chronic And Acute Exercise Modalities On Substrate Utilization And Plasma Adiponectin Concentration, Greggory Ryan Davis

LSU Doctoral Dissertations

Impaired lipid metabolism at rest has been linked to the development of insulin resistance and an attenuation of plasma concentration of the hormone adiponectin. However, it has been suggested that increasing fatty acid oxidation at rest, via exercise or otherwise, may augment plasma adiponectin. The current literature addressing changes substrate utilization and possible direct effects on adiponectin during and following exercise is not well established. Therefore, the purpose of this dissertation was to examine concomitant changes in adiponectin and substrate utilization both at rest and during various exercise modalities, as this may provide implications for improving metabolic responses and in …

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Investigations Into Alkene Hydration And Alkene Oxidation Catalysis, William Schreiter Jan 2013

Investigations Into Alkene Hydration And Alkene Oxidation Catalysis, William Schreiter

LSU Doctoral Dissertations

Bimetallic Ni complexes Ni21M and Ni21R and monometallic transition metal complexes were investigated as possible alkene hydration catalysts under a multitude of different reaction conditions. All attempts at performing this catalytic reaction failed to give any alcohol products. Catalytic screening experiments were conducted using a mixture of racemic-et,ph-P4 and meso-et,ph-P4, 1M and 1R, and various transition metals. These experiments gave several different products including 1-phenylethanol from styrene. During the course of the hydration experiments, an aldehyde product was identified from experiments conducted with the bimetallic complexes in air. Experiments have shown that the aldehyde is produced from the oxidative cleavage …

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Potential Influence Of Blueberry And Black Raspberry Pomace Phenolics On Inflammatory Cytokines In Coronary Cells, Adriana Soto Rodriguez Gil Jan 2013

Potential Influence Of Blueberry And Black Raspberry Pomace Phenolics On Inflammatory Cytokines In Coronary Cells, Adriana Soto Rodriguez Gil

LSU Doctoral Dissertations

Elevated free fatty acids (FFAs) in obesity are known risk factors associated with chronic inflammatory conditions including cardiovascular inflammation and thus cardiovascular disease (CVD), the leading cause of death in the US. Anthocyanins from berries have the potential to provide protection against inflammation in various tissues; however they are poorly absorbed and undergo major transformations by the microbiome. The work presented in this dissertation involves the development and utilization of an in vitro model to characterize the products of colonic fermentation and absorption of blueberry and black raspberry pomace phenolics, and evaluate the potential efficacy of these products compared to …

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Dissection Of Quorum-Sensing Genes In Burkholderia Glumae Reveals Non-Canonical Regulation And The New Regulatory Gene Tofm For Toxoflavin Production, Ruoxi Chen, Inderjit K. Barphagha, Hari S. Karki, Jong Hyun Ham Dec 2012

Dissection Of Quorum-Sensing Genes In Burkholderia Glumae Reveals Non-Canonical Regulation And The New Regulatory Gene Tofm For Toxoflavin Production, Ruoxi Chen, Inderjit K. Barphagha, Hari S. Karki, Jong Hyun Ham

Faculty Publications

Burkholderia glumae causes bacterial panicle blight of rice and produces major virulence factors, including toxoflavin, under the control of the quorum-sensing (QS) system mediated by the luxI homolog, tofI, and the luxR homolog, tofR. In this study, a series of markerless deletion mutants of B. glumae for tofI and tofR were generated using the suicide vector system, pKKSacB, for comprehensive characterization of the QS system of this pathogen. Consistent with the previous studies by other research groups, ΔtofI and ΔtofR strains of B. glumae did not produce toxoflavin in Luria-Bertani (LB) broth. However, these mutants produced high levels of toxoflavin …

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Revision Of The Endemic Malagasy Cavefish Genus Typhleotris (Teleostei: Gobiiformes: Milyeringidae), With Discussion Of Its Phylogenetic Placement And Description Of A New Species, John S. Sparks, Prosanta Chakrabarty Dec 2012

Revision Of The Endemic Malagasy Cavefish Genus Typhleotris (Teleostei: Gobiiformes: Milyeringidae), With Discussion Of Its Phylogenetic Placement And Description Of A New Species, John S. Sparks, Prosanta Chakrabarty

Faculty Publications

Troglobitic cavefishes of the genus Typhleotris, endemic to coastal southwestern Madagascar, are taxonomically reviewed and a new darkly pigmented species, Typhleotris mararybe, is described from an isolated karst sinkhole on the coastal plain below the Mahafaly Plateau. The new species, known only from Grotte de Vitane (Vitany) near the town of Itampolo, is unique among blind cavefishes in being uniformly darkly pigmented, rather than fully depigmented or exceptionally light in coloration. In addition to its dark coloration (vs. depigmented, translucent white body in congeners), the new species can be distinguished from its two congeners, Typhleotris madagascariensis and T. pauliani, by …

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Genomic Impact Of Eukaryotic Transposable Elements, Irina R. Arkhipova, Mark A. Batzer, Juergen Brosius, Cédric Feschotte, John V. Moran, Jürgen Schmitz, Jerzy Jurka Dec 2012

Genomic Impact Of Eukaryotic Transposable Elements, Irina R. Arkhipova, Mark A. Batzer, Juergen Brosius, Cédric Feschotte, John V. Moran, Jürgen Schmitz, Jerzy Jurka

Faculty Publications

The third international conference on the genomic impact of eukaryotic transposable elements (TEs) was held 24 to 28 February 2012 at the Asilomar Conference Center, Pacific Grove, CA, USA. Sponsored in part by the National Institutes of Health grant 5 P41 LM006252, the goal of the conference was to bring together researchers from around the world who study the impact and mechanisms of TEs using multiple computational and experimental approaches. The meeting drew close to 170 attendees and included invited floor presentations on the biology of TEs and their genomic impact, as well as numerous talks contributed by young scientists. …

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Analysis Of Stomach And Gut Microbiomes Of The Eastern Oyster (Crassostrea Virginica) From Coastal Louisiana, Usa, Gary M. King, Craig Judd, Cheryl R. Kuske, Conor Smith Dec 2012

Analysis Of Stomach And Gut Microbiomes Of The Eastern Oyster (Crassostrea Virginica) From Coastal Louisiana, Usa, Gary M. King, Craig Judd, Cheryl R. Kuske, Conor Smith

Faculty Publications

We used high throughput pyrosequencing to characterize stomach and gut content microbiomes of Crassostrea virginica, the Easter oyster, obtained from two sites, one in Barataria Bay (Hackberry Bay) and the other in Terrebonne Bay (Lake Caillou), Louisiana, USA. Stomach microbiomes in oysters from Hackberry Bay were overwhelmingly dominated by Mollicutes most closely related to Mycoplasma; a more rich community dominated by Planctomyctes occurred in Lake Caillou oyster stomachs. Gut communities for oysters from both sites differed from stomach communities, and harbored a relatively diverse assemblage of phylotypes. Phylotypes most closely related to Shewanella and a Chloroflexi strain dominated the Lake …

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Genomic And Physiological Footprint Of The Deepwater Horizon Oil Spill On Resident Marsh Fishes, Andrew Whitehead, Benjamin Dubansky, Charlotte Bodinier, Tzintzuni I. Garcia, Scott Miles, Chet Pilley, Vandana Raghunathan, Jennifer L. Roach, Nan Walker, Ronald B. Walter, Charles D. Rice, Fernando Galvez Dec 2012

Genomic And Physiological Footprint Of The Deepwater Horizon Oil Spill On Resident Marsh Fishes, Andrew Whitehead, Benjamin Dubansky, Charlotte Bodinier, Tzintzuni I. Garcia, Scott Miles, Chet Pilley, Vandana Raghunathan, Jennifer L. Roach, Nan Walker, Ronald B. Walter, Charles D. Rice, Fernando Galvez

Faculty Publications

The biological consequences of the Deepwater Horizon oil spill are unknown, especially for resident organisms. Here, we report results from a field study tracking the effects of contaminating oil across space and time in resident killifish during the first 4 mo of the spill event. Remote sensing and analytical chemistry identified exposures, which were linked to effects in fish characterized by genome expression and associated gill immunohistochemistry, despite very low concentrations of hydrocarbons remaining in water and tissues. Divergence in genome expression coincides with contaminating oil and is consistent with genome responses that are predictive of exposure to hydrocarbon-like chemicals …

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Aggregation And Dynamics Of Oligocholate Transporters In Phospholipid Bilayers Revealed By Solid-State Nmr Spectroscopy, Tuo Wang, Lakmini Widanapathirana, Yan Zhao, Mei Hong Dec 2012

Aggregation And Dynamics Of Oligocholate Transporters In Phospholipid Bilayers Revealed By Solid-State Nmr Spectroscopy, Tuo Wang, Lakmini Widanapathirana, Yan Zhao, Mei Hong

Faculty Publications

Macrocycles made of cholate building blocks were previously found to transport glucose readily across lipid bilayers. In this study, an 15N, 13Cα-labeled glycine was inserted into a cyclic cholate trimer and attached at the end of a linear trimer, respectively. The isotopic labeling allowed us to use solid-state NMR spectroscopy to study the dynamics, aggregation, and depth of insertion of these compounds in lipid membranes. The cyclic compound was found to be mostly immobilized in DLPC, POPC/POPG, and POPC/POPG/cholesterol membranes, whereas the linear trimer displayed large-amplitude motion that depended on the membrane thickness and viscosity. 13C-detected 1H spin diffusion experiments …

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Protein Dynamics And Ion Traffic In Bacterioferritin, Huan Rui, Mario Rivera, Wonpil Im Dec 2012

Protein Dynamics And Ion Traffic In Bacterioferritin, Huan Rui, Mario Rivera, Wonpil Im

Faculty Publications

Bacterioferritin (Bfr) is a spherical protein composed of 24 subunits and 12 heme molecules. Bfrs contribute to regulate iron homeostasis in bacteria by capturing soluble but potentially toxic Fe2+ and by compartmentalizing it in the form of a bioavailable ferric mineral inside the protein's hollow cavity. When iron is needed, Fe3+ is reduced and mobilized into the cytosol as Fe2+. Hence, key to the function of Bfr is its ability to permeate iron ions in and out of its interior cavity, which is likely imparted by a flexible protein shell. To examine the conformational flexibility of Bfrs in a native-like …

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Impact Of The Deepwater Horizon Oil Spill On A Deep-Water Coral Community In The Gulf Of Mexico, Helen K. White, Pen Yuan Hsing, Walter Cho, Timothy M. Shank, Erik E. Cordes, Andrea M. Quattrini, Robert K. Nelson, Richard Camilli, Amanda W.J. Demopoulos, Christopher R. German, James M. Brooks, Harry H. Roberts, William Shedd, Christopher M. Reddy, Charles R. Fisher Dec 2012

Impact Of The Deepwater Horizon Oil Spill On A Deep-Water Coral Community In The Gulf Of Mexico, Helen K. White, Pen Yuan Hsing, Walter Cho, Timothy M. Shank, Erik E. Cordes, Andrea M. Quattrini, Robert K. Nelson, Richard Camilli, Amanda W.J. Demopoulos, Christopher R. German, James M. Brooks, Harry H. Roberts, William Shedd, Christopher M. Reddy, Charles R. Fisher

Faculty Publications

To assess the potential impact of the Deepwater Horizon oil spill on offshore ecosystems, 11 sites hosting deep-water coral communities were examined 3 to 4 mo after the well was capped. Healthy coral communities were observed at all sites >20 km from the Macondo well, including seven sites previously visited in September 2009, where the corals and communities appeared unchanged. However, at one site 11 km southwest of the Macondo well, coral colonies presented widespread signs of stress, including varying degrees of tissue loss, sclerite enlargement, excessmucous production, bleached commensal ophiuroids, and covering by brown flocculent material (floc). On the …

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Microbial Life At -13°C In The Brine Of An Ice-Sealed Antarctic Lake, Alison E. Murray, Fabien Kenig, Christian H. Fritsen, Christopher P. Mckay, Kaelin M. Cawley, Ross Edwards, Emanuele Kuhn, Diane M. Mcknight, Nathaniel E. Ostrom, Vivian Peng, Adrian Ponce, John C. Priscu, Vladimir Samarkin, Ashley T. Townsend, Protima Wagh, Seth A. Young, Pung To Yung, Peter T. Doran Dec 2012

Microbial Life At -13°C In The Brine Of An Ice-Sealed Antarctic Lake, Alison E. Murray, Fabien Kenig, Christian H. Fritsen, Christopher P. Mckay, Kaelin M. Cawley, Ross Edwards, Emanuele Kuhn, Diane M. Mcknight, Nathaniel E. Ostrom, Vivian Peng, Adrian Ponce, John C. Priscu, Vladimir Samarkin, Ashley T. Townsend, Protima Wagh, Seth A. Young, Pung To Yung, Peter T. Doran

Faculty Publications

The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (-13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida's brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol·L-1 …

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Impact Of Margin Size On The Predicted Risk Of Radiogenic Second Cancers Following Proton Arc Therapy And Volumetric Modulated Arc Therapy For Prostate Cancer, Laura A. Rechner, Rebecca M. Howell, Rui Zhang, Wayne D. Newhauser Dec 2012

Impact Of Margin Size On The Predicted Risk Of Radiogenic Second Cancers Following Proton Arc Therapy And Volumetric Modulated Arc Therapy For Prostate Cancer, Laura A. Rechner, Rebecca M. Howell, Rui Zhang, Wayne D. Newhauser

Faculty Publications

We previously determined that the predicted risk of radiogenic second cancer in the bladder and rectum after proton arc therapy (PAT) was less than or equal to that after volumetric modulated arc therapy (VMAT) with photons, but we did not consider the impact of margin size on that risk. The current study was thus conducted to evaluate margin size's effect on the predicted risks of second cancer for the two modalities and the relative risk between them. Seven treatment plans with margins ranging from 0 mm in all directions to 6 mm posteriorly and 8 mm in all other directions …

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O-Glcnac Transferase Invokes Nucleotide Sugar Pyrophosphate Participation In Catalysis, Marianne Schimpl, Xiaowei Zheng, Vladimir S. Borodkin, David E. Blair, Andrew T. Ferenbach, Alexander W. Schüttelkopf, Iva Navratilova, Tonia Aristotelous, Osama Albarbarawi, David A. Robinson, Megan A. Macnaughtan, Daan M.F. Van Aalten Dec 2012

O-Glcnac Transferase Invokes Nucleotide Sugar Pyrophosphate Participation In Catalysis, Marianne Schimpl, Xiaowei Zheng, Vladimir S. Borodkin, David E. Blair, Andrew T. Ferenbach, Alexander W. Schüttelkopf, Iva Navratilova, Tonia Aristotelous, Osama Albarbarawi, David A. Robinson, Megan A. Macnaughtan, Daan M.F. Van Aalten

Faculty Publications

Protein O-GlcNAcylation is an essential post-translational modification on hundreds of intracellular proteins in metazoa, catalyzed by O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT) using unknown mechanisms of transfer and substrate recognition. Through crystallographic snapshots and mechanism-inspired chemical probes, we define how human OGT recognizes the sugar donor and acceptor peptide and uses a new catalytic mechanism of glycosyl transfer, involving the sugar donor α-phosphate as the catalytic base as well as an essential lysine. This mechanism seems to be a unique evolutionary solution to the spatial constraints imposed by a bulky protein acceptor substrate and explains the unexpected specificity of a recently …

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Bose-Einstein Condensation: A Transition To Chaos Result, Stefania Ugolini Dec 2012

Bose-Einstein Condensation: A Transition To Chaos Result, Stefania Ugolini

Communications on Stochastic Analysis

No abstract provided.

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Jak/Stat3 Signaling Promotes Somatic Cell Reprogramming By Epigenetic Regulation, Yong Tang, Yan Luo, Zongliang Jiang, Yinghong Ma, Chih Jen Lin, Chul Kim, Mark G. Carter, Tomokazu Amano, Joonghong Park, Sharon Kish, Xiuchun Tian Dec 2012

Jak/Stat3 Signaling Promotes Somatic Cell Reprogramming By Epigenetic Regulation, Yong Tang, Yan Luo, Zongliang Jiang, Yinghong Ma, Chih Jen Lin, Chul Kim, Mark G. Carter, Tomokazu Amano, Joonghong Park, Sharon Kish, Xiuchun Tian

Faculty Publications

Although leukemia inhibitory factor (LIF) maintains the ground state pluripotency of mouse embryonic stem cells and induced pluripotent stem cells (iPSCs) by activating the Janus kinase/signal transducer and activator of transcription 3 (Jak/Stat3) pathway, the mechanism remained unclear. Stat3 has only been shown to promote complete reprogramming of epiblast and neural stem cells and partially reprogrammed cells (pre-iPSCs). We investigated if and how Jak/Stat3 activation promotes reprogramming of terminally differentiated mouse embryonic fibroblasts (MEFs). We demonstrated that activated Stat3 not only promotes but also is essential for the pluripotency establishment of MEFs during reprogramming. We further demonstrated that during this …

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Syntheses And Photodynamic Activity Of Pegylated Cationic Zn(Ii)-Phthalocyanines In Hep2 Cells, Benson G. Ongarora, Xiaoke Hu, Susan D. Verberne-Sutton, Jayne C. Garno, M. Graça H. Vicente Dec 2012

Syntheses And Photodynamic Activity Of Pegylated Cationic Zn(Ii)-Phthalocyanines In Hep2 Cells, Benson G. Ongarora, Xiaoke Hu, Susan D. Verberne-Sutton, Jayne C. Garno, M. Graça H. Vicente

Faculty Publications

Di-cationic Zn(II)-phthalocyanines (ZnPcs) are promising photosensitizers for the photody-namic therapy (PDT) of cancers and for photoinactivation of viruses and bacteria. Pegylation of photosensitizers in general enhances their water-solubility and tumor cell accumulation. A series of pegylated di-cationic ZnPcs were synthesized from conjugation of a low molecular weight PEG group to a pre-formed Pc macrocycle, or by mixed condensation involving a pegylated phthalonitrile. All pegylated ZnPcs were highly soluble in polar organic solvents but were insoluble in water; they have intense Q absorptions centered at 680 nm and fluores-cence quantum yields of ca. 0.2 in DMF. The non-pegylated di-cationic ZnPc 6a …

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Analysis Of Composition And Structure Of Coastal To Mesopelagic Bacterioplankton Communities In The Northern Gulf Of Mexico, Gary M. King, Conor B. Smith, Bradley Tolar, James T. Hollibaugh Dec 2012

Analysis Of Composition And Structure Of Coastal To Mesopelagic Bacterioplankton Communities In The Northern Gulf Of Mexico, Gary M. King, Conor B. Smith, Bradley Tolar, James T. Hollibaugh

Faculty Publications

16S rRNA gene amplicons were pyrosequenced to assess bacterioplankton community composition, diversity, and phylogenetic community structure for 17 stations in the northern Gulf of Mexico (nGoM) sampled in March 2010. Statistical analyses showed that sam ples from depths ≤100 m differed distinctly from deeper samples. SAR 11 α-Proteobacteria and Bacteroidetes dominated communities at depths ≤100 m, which were characterized by high α-Proteobacteria/γ-Proteobacteria ratios (α/γ > 1.7). Thaumarchaeota, Firmicutes, and δ-Proteobacteria were relatively abundant in deeper waters, and α/γ ratios were low (<1). Canonical correlation analysis indicated that δ- and γ-Proteobacteria,Thaumarchaeota, and Firmicutes correlated positively with depth; α-Proteobacteria and Bacteroidetes correlated positively with temperature and dissolved oxygen; Actinobacteria, β-Proteobacteria, and Verrucomicrobia correlated positively with a measure of suspended particles. Diversity indices did not vary with depth or other factors, which indicated that richness and evenness elements of bacterioplankton communities might develop independently of nGoM physical-chemical variables. Phylogenetic community structure as measured by the net relatedness (NRI) and nearest taxon (NTI) indices also did not vary with depth. NRI values indicated that most of the communities were comprised of OTUs more distantly related to each other in whole community comparisons than expected by chance. NTI values derived from phylogenetic distances of the closest neighbor for each OTU in a given community indicated that OTUs tended to occur in clusters to a greater extent than expected by chance. This indicates that "habitat filtering" might play an important role in nGoM bacterioplankton species assembly, and that such filtering occurs throughout the water column.© 2013 King, Smith, Tolar and Hollibaugh.

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Modeling The Influence Of Peromyscus Leucopus Body Mass, Sex, And Habitat On Immature Dermacentor Variabilis Burden, Tad A. Dallas, Stephanie A. Foré, Hyun Joo Kim Dec 2012

Modeling The Influence Of Peromyscus Leucopus Body Mass, Sex, And Habitat On Immature Dermacentor Variabilis Burden, Tad A. Dallas, Stephanie A. Foré, Hyun Joo Kim

Faculty Publications

mmature (larvae and nymph) tick burden on rodents is an important determinant of adult tick population size and understanding infectious disease dynamics. The objective of this research was to build a descriptive model for immature Dermacentor variabilis burden on Peromyscus leucopus. Mice were live-trapped on two permanent grids in an old field and an early successional forest every other month between April and October, 2006-2009. Negative binomial regression was used to examine the association between immature D. variabilis burden and the host related variables of host habitat, body mass, and/or sex. The model containing all three variables had the lowest …

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Competition Of Zinc Ion For The [2fe-2s] Cluster Binding Site In The Diabetes Drug Target Protein Mitoneet, Guoqiang Tan, Aaron P. Landry, Ruili Dai, Li Wang, Jianxin Lu, Huangen Ding Dec 2012

Competition Of Zinc Ion For The [2fe-2s] Cluster Binding Site In The Diabetes Drug Target Protein Mitoneet, Guoqiang Tan, Aaron P. Landry, Ruili Dai, Li Wang, Jianxin Lu, Huangen Ding

Faculty Publications

Human mitochondrial protein mitoNEET is a novel target of type II diabetes drug pioglitazone, and contains a redox active [2Fe-2S] cluster that is hosted by a unique ligand arrangement of three cysteine and one histidine residues. Here we report that zinc ion can compete for the [2Fe-2S] cluster binding site in human mitoNEET and potentially modulate the physiological function of mitoNEET. When recombinant mitoNEET is expressed in Escherichia coli cells grown in M9 minimal media, purified mitoNEET contains very little or no iron-sulfur clusters. Addition of exogenous iron or zinc ion in the media produces mitoNEET bound with a [2Fe-2S] …

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Efficacy Of Foliar Insecticides On Eggs Of Nezara Viridula (Hemiptera: Pentatomidae), Sebe A. Brown, Jeffrey A. Davis, Arthur R. Richter Dec 2012

Efficacy Of Foliar Insecticides On Eggs Of Nezara Viridula (Hemiptera: Pentatomidae), Sebe A. Brown, Jeffrey A. Davis, Arthur R. Richter

Faculty Publications

Stink bugs (Hemiptera: Pentatomidae) are important insect pests of crops. Stink bug feeding reduces yields, lowers crop quality, induces delayed maturity, and wounds tissues allowing for pathogen entry. Historically, effective adult and nymph control of stink bugs has been with insecticides. However, little insecticide efficacy against stink bug eggs is known. The objective of this study was to determine how foliar insecticides currently recommend for southern green stink bug, Nezara viridula (L.), control in soybean impact pre-emergence nymphal mortality using an egg dip bioassay. Eight formulate insecticides were tested. Differences in nymphal stink bug pre-emergence mortality were recorded. The lowest …

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Improved Chemical Control For The Mexican Rice Borer (Lepidoptera: Crambidae) In Sugarcane: Larval Exposure, A Novel Scouting Method, And Efficacy Of A Single Aerial Insecticide Application, B. E. Wilson, A. T. Showler, T. E. Reagan, J. M. Beuzelin Dec 2012

Improved Chemical Control For The Mexican Rice Borer (Lepidoptera: Crambidae) In Sugarcane: Larval Exposure, A Novel Scouting Method, And Efficacy Of A Single Aerial Insecticide Application, B. E. Wilson, A. T. Showler, T. E. Reagan, J. M. Beuzelin

Faculty Publications

A three-treatment aerial application insecticide experiment was conducted in five commercial sugarcane, Saccharum spp., fields in south Texas to evaluate the use of pheromone traps for improving chemical control of the Mexican rice borer, Eoreuma loftini (Dyar), in 2009 and 2010. A threshold of 20 moths/trap/wk was used to initiate monitoring for larval infestations. The percentage of stalks with larvae on plant surfaces was directly related to the number of moths trapped. Reductions in borer injury and adult emergence were detected when a threshold of >5% of stalks with larvae present on plant surfaces was used to trigger insecticide applications. …

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Bioactivity Of Selected Eco-Friendly Pesticides Against Cylas Formicarius (Coleoptera: Brentidae), Peter H. Leng, Gadi V.P. Reddy Dec 2012

Bioactivity Of Selected Eco-Friendly Pesticides Against Cylas Formicarius (Coleoptera: Brentidae), Peter H. Leng, Gadi V.P. Reddy

Faculty Publications

Seven low risk pesticides including 1.2% azadirachtin (Azadirachta indica), extracts from Morinda citrifolia, petroleum oil 97%, Beauveria bassiana strain GHA, mixed essential oils (rosemary oil: 0.25%, peppermint oil: 0.25%, thyme oil: 0.25%, clove oil: 0.25% and other ingredients: 99.00%), spinosad and malathion, were evaluated against adults of the sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae) to determine potential insecticidal, repellent and feeding deterrence effects. Among the pesticides tested, A. indica and spinosad showed high insecticidal, repellent and feeding deterrence activity against C. formicarius. Spinosad, A. indica and malathion showed significantly higher insecticidal activity against C. formicarius. Similarly, these pesticides showed …

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Development Of A Plant-Based Threshold For Tarnished Plant Bug (Hemiptera: Miridae) In Cotton, J. Gore, A. Catchot, F. Musser, J. Greene, B. R. Leonard, D. R. Cook, G. L. Snodgrass, R. Jackson Dec 2012

Development Of A Plant-Based Threshold For Tarnished Plant Bug (Hemiptera: Miridae) In Cotton, J. Gore, A. Catchot, F. Musser, J. Greene, B. R. Leonard, D. R. Cook, G. L. Snodgrass, R. Jackson

Faculty Publications

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important pest of cotton, Gossypium hirsutum L., in the mid-southern United States. It is exclusively controlled with foliar insecticide applications, and sampling methods and thresholds need to be revisited. The current experiment was designed to establish a plant-based threshold during the flowering period of cotton development. Experiments were conducted in Mississippi in 2005 and 2006, Arkansas in 2005, and Louisiana in 2005 through 2008. Treatments consisted of various combinations of thresholds based on the percentage of dirty squares that were compared with the current threshold with a drop cloth …

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Laboratory Study Of The Influence Of Substrate Type And Temperature On The Exploratory Tunneling By Formosan Subterranean Termite, Bal K. Gautam, Gregg Henderson Dec 2012

Laboratory Study Of The Influence Of Substrate Type And Temperature On The Exploratory Tunneling By Formosan Subterranean Termite, Bal K. Gautam, Gregg Henderson

Faculty Publications

Using two-dimensional foraging arenas, laboratory tests were conducted to investigate the effect of soil type, soil moisture level and ambient temperature on the exploratory tunneling by Coptotermes formosanus Shiraki. In choice arenas consisting of two substrate types having two moisture levels each, and conducted at a constant temperature of 22 °C, a significantly greater proportion of termites aggregated in sand than in sandy loam. Similarly, the length of excavated tunnels was also increased in sand. In a given substrate, termite aggregation or tunnel length did not differ between 5% and 15% moisture levels. In no-choice tests, where three different substrates …

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