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Quantifying Sulfate Components And Their Variations In Soils Of The Mcmurdo Dry Valleys, Antarctica, Huiming Bao, David R. Marchant Aug 2006

Quantifying Sulfate Components And Their Variations In Soils Of The Mcmurdo Dry Valleys, Antarctica, Huiming Bao, David R. Marchant

Faculty Publications

Many soils of the McMurdo Dry Valleys (MDV), Antarctica, being old, hyperarid, and frigid, have accumulated abundant atmospheric salts over the last several million years. This salt repository offers an opportunity to study atmospheric chemistry (past and present), the origin and transport of ions in soils, the weathering activity of soils, and postdepositional soil-leaching processes within this unique environment. In particular, soil sulfate in the MDV is known to have multiple origins, but the precise proportions of different sulfate components remain elusive. Here we test a hypothesis that soil sulfate in the MDV is a predictable mixture of three major …

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Stereoselectivity Of 8-Oh-Dpat Toward The Serotonin 5-Ht1a Receptor: Biochemical And Molecular Modeling Study, Joanna Dabrowska, Michal Brylinski Aug 2006

Stereoselectivity Of 8-Oh-Dpat Toward The Serotonin 5-Ht1a Receptor: Biochemical And Molecular Modeling Study, Joanna Dabrowska, Michal Brylinski

Faculty Publications

The great majority of pharmacological investigations of 5-HT1A receptors' reactivity has been performed using racemic 8-OH-DPAT, therefore the biochemical as well as behavioral profiles of both 8-OH-DPAT enantiomers are not circumstantiated. In the biochemical study capability of racemic 8-OH-DPAT (0.05, 0.1 mg/kg s.c.) and its counterparts R-8-OH-DPAT (0.05, 0.1 mg/kg s.c.) and S-8-OH-DPAT (0.05, 0.1 mg/kg s.c.) to influence 5-HT synthesis rate in rats' prefrontal cortex, hypothalamus, hippocampus and brainstem was evaluated by HPLC/ED technique. Biochemical results are supported by the exhaustive computational study of possible differences between R- and S-enantiomer toward the 5-HT1A receptor. A reliable 3D model of …

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Exposure Of Neonates To Respiratory Syncytial Virus Is Critical In Determining Subsequent Airway Response In Adults, Dahui You, David Becnel, Kai Wang, Michael Ripple, Melissa Daly, Stephania A. Cormier Aug 2006

Exposure Of Neonates To Respiratory Syncytial Virus Is Critical In Determining Subsequent Airway Response In Adults, Dahui You, David Becnel, Kai Wang, Michael Ripple, Melissa Daly, Stephania A. Cormier

Faculty Publications

Background: Respiratory syncytial virus (RSV) is the most common cause of acute bronchiolitis in infants and the elderly. Furthermore, epidemiological data suggest that RSV infection during infancy is a potent trigger of subsequent wheeze and asthma development. However, the mechanism by which RSV contributes to asthma is complex and remains largely unknown. A recent study indicates that the age of initial RSV infection is a key factor in determining airway response to RSV rechallenge. We hypothesized that severe RSV infection during neonatal development significantly alters lung structure and the pulmonary immune micro-environment; and thus, neonatal RSV infection is crucial in …

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Crystal Structure Of Dps-1, A Functionally Distinct Dps Protein From Deinococcus Radiodurans, Song Gun Kim, Gargi Bhattacharyya, Anne Grove, Yong Hwan Lee Aug 2006

Crystal Structure Of Dps-1, A Functionally Distinct Dps Protein From Deinococcus Radiodurans, Song Gun Kim, Gargi Bhattacharyya, Anne Grove, Yong Hwan Lee

Faculty Publications

DNA protection during starvation (Dps) proteins play an important role in protecting cellular macromolecules from damage by reactive oxygen species (ROS). Unlike most orthologs that protect DNA by a combination of DNA binding and prevention of hydroxyl radical formation by ferroxidation and sequestration of iron, Dps-1 from the radiation-resistant Deinococcus radiodurans fails to protect DNA from hydroxyl radical-mediated cleavage through a mechanism inferred to involve continuous release of iron from the protein core. To address the structural basis for this unusual release of Fe2+, the crystal structure of D. radiodurans Dps-1 was determined to 2.0 Å resolution. Two of four …

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A Chemomechanical Polymer That Functions In Blood Plasma With High Glucose Selectivity, George K. Samoei, Weihua Wang, Jorge O. Escobedo, Xiangyang Xu, Hans Jörg Schneider, Robert L. Cook, Robert M. Strongin Aug 2006

A Chemomechanical Polymer That Functions In Blood Plasma With High Glucose Selectivity, George K. Samoei, Weihua Wang, Jorge O. Escobedo, Xiangyang Xu, Hans Jörg Schneider, Robert L. Cook, Robert M. Strongin

Faculty Publications

(Figure Presented) See the shrink: Systematic modification of poly(methyl methacrylate) leads to a chemomechanical polymer that selectively contracts in the presence of glucose at physiological levels in human blood plasma. The polymer also exhibits good reversibility allowing continuous expansion-contraction cycles. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.

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Thermalkalibacillus Uzonensis Gen. Nov. Sp. Nov, A Novel Aerobic Alkali-Tolerant Thermophilic Bacterium Isolated From A Hot Spring In Uzon Caldera, Kamchatka, Weidong Zhao, Carolyn Weber, Chuanlun L. Zhang, Christopher S. Romanek, Gary M. King, Gary Mills, Tatyana Sokolova, Juergen Wiegel Aug 2006

Thermalkalibacillus Uzonensis Gen. Nov. Sp. Nov, A Novel Aerobic Alkali-Tolerant Thermophilic Bacterium Isolated From A Hot Spring In Uzon Caldera, Kamchatka, Weidong Zhao, Carolyn Weber, Chuanlun L. Zhang, Christopher S. Romanek, Gary M. King, Gary Mills, Tatyana Sokolova, Juergen Wiegel

Faculty Publications

A novel thermophilic, alkali-tolerant, and CO-tolerant strain JW/WZ-YB58T was isolated from green mat samples obtained from the Zarvarzin II hot spring in the Uzon Caldera, Kamchatka (Far East Russia). Cells were Gram-type and Gram stain-positive, strictly aerobic, 0.7-0.8 μm in width and 5.5-12 μm in length and produced terminal spherical spores of 1.2-1.6 μm in diameter with the mother cell swelling around 2 μm in diameter (drumstick-type morphology). Cells grew optimally at pH25°C 8.2-8.4 and temperature 50-52°C and tolerated maximally 6% (w/v) NaCl. They were strict heterotrophs and could not use either CO or CO2 (both with or without H2) …

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Parasites In A Biodiversity Hotspot: A Survey Of Hematozoa And A Molecular Phylogenetic Analysis Of Plasmodium In New Guinea Skinks, Christopher C. Austin, Susan L. Perkins Aug 2006

Parasites In A Biodiversity Hotspot: A Survey Of Hematozoa And A Molecular Phylogenetic Analysis Of Plasmodium In New Guinea Skinks, Christopher C. Austin, Susan L. Perkins

Faculty Publications

A sample of 204 skinks (Squamata: Scincidae) from 10 genera representing 24 species were collected from 10 different localities in New Guinea and examined for blood parasites. Hemogregarines, trypanosomes, microfilarial worms, and 8 infections showing 2 distinct morphological types of malaria parasites (Plasmodium sp.) were observed. Molecular sequence data, in the form of mitochondrial cytochrome b sequences from the Plasmodium infections, showed 2 distinct clades of parasites, 1 in Sphenomorphus jobiense hosts and 1 in Emoia spp., which correspond to the 2 morphotypes. There was substantial genetic variation between the 2 clades, as well as within the clade of Emoia …

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Rickettsia Felis From Cat Fleas: Isolation And Culture In A Tick-Derived Cell Line, Walairat Pornwiroon, Susan S. Pourciau, Lane D. Foil, Kevin R. Macaluso Aug 2006

Rickettsia Felis From Cat Fleas: Isolation And Culture In A Tick-Derived Cell Line, Walairat Pornwiroon, Susan S. Pourciau, Lane D. Foil, Kevin R. Macaluso

Faculty Publications

Rickettsia felis, the etiologic agent of spotted fever, is maintained in cat fleas by vertical transmission and resembles other tick-borne spotted fever group rickettsiae. In the present study, we utilized an Ixodes scapularis-derived tick cell line, ISE6, to achieve isolation and propagation of R. felis. A cytopathic effect of increased vacuolization was commonly observed in R. felis-infected cells, while lysis of host cells was not evident despite large numbers of rickettsiae. Electron microscopy identified rickettsia-like organisms in ISE6 cells, and sequence analyses of portions of the citrate synthase (gltA), 16S rRNA, Rickettsia genus-specific 17-kDa antigen, and spotted fever group-specific outer …

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The Northeastern Black Sea Redox Zone: Hydrochemical Structure And Its Temporal Variability, E. V. Yakushev, V. K. Chasovnikov, E. I. Debolskaya, A. V. Egorov, P. N. Makkaveev, S. V. Pakhomova, O. I. Podymov, V. G. Yakubenko Aug 2006

The Northeastern Black Sea Redox Zone: Hydrochemical Structure And Its Temporal Variability, E. V. Yakushev, V. K. Chasovnikov, E. I. Debolskaya, A. V. Egorov, P. N. Makkaveev, S. V. Pakhomova, O. I. Podymov, V. G. Yakubenko

Faculty Publications

Detailed studies of the vertical structure of hydrochemical parameters in the northeastern Black Sea near Gelendzhik are presented and discussed. This work is based on a set of systematic observations carried out in this region during R/V "Akvanavt" and R/V "Ashamba" cruises from 1997 to 2005 and also on data from previous studies from 1984 to 1997. The Black Sea region near Gelendzhik is far from the influences of the Bosporus input and Danube River inflow. Therefore, the vertical structure in this region is more stable compared to the western Black Sea and reflects "integrated," rather than local, changes of …

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Modulation And Lack Of Cross-Talk Between Signal Transducer And Activator Of Transcription 5 And Suppressor Of Cytokine Signaling-3 In Insulin And Growth Hormone Signaling In 3t3-L1 Adipocytes, David J. Story, Jacqueline M. Stephens Aug 2006

Modulation And Lack Of Cross-Talk Between Signal Transducer And Activator Of Transcription 5 And Suppressor Of Cytokine Signaling-3 In Insulin And Growth Hormone Signaling In 3t3-L1 Adipocytes, David J. Story, Jacqueline M. Stephens

Faculty Publications

Objective: To examine the role of signal transducer and activator of transcription (STAT) 5 and suppressor of cytokine signaling (SOCS)-3 in the cross-talk between growth hormone and insulin (INS) signaling in fat cells. Research Methods and Procedures: Fully differentiated 3T3-L1 adipocytes were exposed to INS, growth hormone (GH), or both of these growth factors, and the activation of STAT5 proteins and mitogen-activated protein kinase was examined using phospho-specific antibodies. The induction of SOCS-3 mRNA was assessed by Northern blot analysis. INS-stimulated glucose transport was also measured. Results: We observed that GH, not INS, induced STAT5 activation in adipocytes in a …

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The Drosophila Boundary Element-Associated Factors Beaf-32a And Beaf-32b Affect Chromatin Structure, Matthew K. Gilbert, Yian Yee Tan, Craig M. Hart Aug 2006

The Drosophila Boundary Element-Associated Factors Beaf-32a And Beaf-32b Affect Chromatin Structure, Matthew K. Gilbert, Yian Yee Tan, Craig M. Hart

Faculty Publications

Binding sites for the Drosophila boundary element-associated factors BEAF-32A and -32B are required for the insulator activity of the scs' insulator. BEAF binds to hundreds of sites on polytene chromosomes, indicating that BEAF-utilizing insulators are an important class in Drosophila. To gain insight into the role of BEAF in flies, we designed a transgene encoding a dominant-negative form of BEAF under GAL4 UAS control. This BID protein encompasses the BEAF self-interaction domain. Evidence is provided that BID interacts with BEAF and interferes with scs' insulator activity and that BEAF is the major target of BID in vivo. BID expression during …

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Health In Cuba, Richard S. Cooper, Joan F. Kennelly, Pedro Orduñez-Garcia Aug 2006

Health In Cuba, Richard S. Cooper, Joan F. Kennelly, Pedro Orduñez-Garcia

Faculty Publications

The poorer countries of the world continue to struggle with an enormous health burden from diseases that we have long had the capacity to eliminate. Similarly, the health systems of some countries, rich and poor alike, are fragmented and inefficient, leaving many population groups underserved and often without health care access entirely. Cuba represents an important alternative example where modest infrastructure investments combined with a well-developed public health strategy have generated health status measures comparable with those of industrialized countries. Areas of success include control of infectious diseases, reduction in infant mortality, establishment of a research and biotechnology industry, and …

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Integrating Software Into Pra: A Software-Related Failure Mode Taxonomy, Bin Li, Ming Li, Ken Chen, Carol Smidts Aug 2006

Integrating Software Into Pra: A Software-Related Failure Mode Taxonomy, Bin Li, Ming Li, Ken Chen, Carol Smidts

Faculty Publications

Probabilistic risk assessment is a methodology to assess the probability of failure or success of a mission. Results provided by the risk assessment methodology are used to make decisions concerning choice of upgrades, scheduling of maintenance, decision to launch, etc. However, current PRA neglects the contribution of software to the risk of failure of the mission. Our research has developed a methodology to account for the impact of software to system failure. This article focuses on an element of the approach: a comprehensive taxonomy of software-related failure modes. Application of the taxonomy is discussed in this article. A validation of …

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Absence Of The Psbq Protein Results In Destabilization Of The Psbv Protein And Decreased Oxygen Evolution Activity In Cyanobacterial Photosystem Ii, Yasuhiro Kashino, Natsuko Inoue-Kashino, Johnna L. Roose, Himadri B. Pakrasi Jul 2006

Absence Of The Psbq Protein Results In Destabilization Of The Psbv Protein And Decreased Oxygen Evolution Activity In Cyanobacterial Photosystem Ii, Yasuhiro Kashino, Natsuko Inoue-Kashino, Johnna L. Roose, Himadri B. Pakrasi

Faculty Publications

We have previously reported that cyanobacterial photosystem II (PS II) contains a protein homologous to PsbQ, the extrinsic 17-kDa protein found in higher plant and green algal PS II (Kashino, Y., Lauber, W. M., Carroll, J. A., Wang, Q., Whitmarsh, J., Satoh, K., and Pakrasi, H. B. (2002) Biochemistry 41, 8004-8012) and that it has regulatory role(s) on the water oxidation machinery (Thornton, L. E., Ohkawa, H., Roose, J. L., Kashino, Y., Keren, N., and Pakrasi, H. B. (2004) Plant Cell 16, 2164-2175). In this work, the localization and the function of PsbQ were assessed using the cyanobacterium Synechocystis sp. …

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Phylogeny Of The Parasitic Plant Family Orobanchaceae Inferred From Phytochrome A, Jonathan R. Bennett, Sarah Mathews Jul 2006

Phylogeny Of The Parasitic Plant Family Orobanchaceae Inferred From Phytochrome A, Jonathan R. Bennett, Sarah Mathews

Faculty Publications

Partial sequences of the nuclear gene encoding the photoreceptor phytochrome A (PHYA) are used to reconstruct relationships within Orobanchaceae, the largest of the parasitic angiosperm families. The monophyly of Orobanchaceae, including nonphotosynthetic holoparasites, hemiparasites, and nonparasitic Lindenbergia is strongly supported. Phytochrome A data resolve six well-supported lineages that contain all of the sampled genera except Brandisia, which is sister to the major radiation of hemiparasites. In contrast to previous plastid and ITS trees, relationships among these major clades also are generally well supported. Thus, the robust phylogenetic hypothesis inferred from the PHYA data provides a much better context in which …

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Synthesis And Biological Evaluation Of Manzamine Analogues, Jeffrey D. Winkler, Allyn T. Londregan, Justin R. Ragains, Mark T. Hamann Jul 2006

Synthesis And Biological Evaluation Of Manzamine Analogues, Jeffrey D. Winkler, Allyn T. Londregan, Justin R. Ragains, Mark T. Hamann

Faculty Publications

The synthesis and biological evaluation of a series of analogues of manzamine A, representing partial structures of the pentacyclic ABCDE diamine core, is described. All new compounds were screened against Plasmodium falciparum and demonstrated attenuated antimalarial activity relative to that of manzamine A. © 2006 American Chemical Society.

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Classical Biological Control Of The Papaya Mealybug, Paracoccus Marginatus (Hemiptera: Pseudococcidae) In The Republic Of Palau, R. Muniappan, D. E. Meyerdirk, F. M. Sengebau, D. D. Berringer, G. V.P. Reddy Jul 2006

Classical Biological Control Of The Papaya Mealybug, Paracoccus Marginatus (Hemiptera: Pseudococcidae) In The Republic Of Palau, R. Muniappan, D. E. Meyerdirk, F. M. Sengebau, D. D. Berringer, G. V.P. Reddy

Faculty Publications

The papaya mealybug (PM), Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae), a pest in Central America and the Caribbean, was noted to have established on Palau in March 2003 and was causing serious damage to papaya, plumeria, hibiscus, and other plants. The parasitoids Anagyrus loecki Noyes, Pseudleptomastix mexicana Noyes and Schauff, and Acerophagus papayae Noyes and Schauff (Hymenoptera: Encyrtidae) totaling 24,586 were imported from Puerto Rico and field released in Palau from August 2003 to June 2004. Anagyrus loecki and A. papayae appear to be promising biological control agents of PM in Palau. No field recovery of P. …

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Identification Of Clustered Yy1 Binding Sites In Imprinting Control Regions, Jeong Do Kim, Angela K. Hinz, Anne Bergmann, Jennifer M. Huang, Ivan Ovcharenko, Lisa Stubbs, Joomyeong Kim Jul 2006

Identification Of Clustered Yy1 Binding Sites In Imprinting Control Regions, Jeong Do Kim, Angela K. Hinz, Anne Bergmann, Jennifer M. Huang, Ivan Ovcharenko, Lisa Stubbs, Joomyeong Kim

Faculty Publications

Mammalian genomic imprinting is regulated by imprinting control regions (ICRs) that are usually associated with tandem arrays of transcription factor binding sites. In this study, the sequence features derived from a tandem array of YY1 binding sites of Peg3-DMR (differentially methylated region) led us to identify three additional clustered YY1 binding sites, which are also localized within the DMRs of Xist, Tsix, and Nespas. These regions have been shown to play a critical role as ICRs for the regulation of surrounding genes. These ICRs have maintained a tandem array of YY1 binding sites during mammalian evolution. The in vivo binding …

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The Importance Of Demographic Niches To Tree Diversity, Richard Condit, Peter Ashton, Sarayudh Bunyavejchewin, H. S. Dattaraja, Stuart Davies, Shameema Esufali, Corneille Ewango, Robin Foster, I. A.U.N. Gunatilleke, C. V.S. Gunatilleke, Pamela Hall, Kyle E. Harms, Terese Hart, Consuelo Hernandez, Stephen Hubbell, Akira Itoh, Somboon Kiratiprayoon, James Lafrankie, Suzanne Loo De Lao, Jean Remy Makana, Md Nur Supardi Noor, Abdul Rahman Kassim, Sabrina Russo, Raman Sukumar, Cristián Samper, Hebbalalu S. Suresh, Sylvester Tan, Sean Thomas, Renato Valencia, Martha Vallejo, Gorky Villa, Tommaso Zillio Jul 2006

The Importance Of Demographic Niches To Tree Diversity, Richard Condit, Peter Ashton, Sarayudh Bunyavejchewin, H. S. Dattaraja, Stuart Davies, Shameema Esufali, Corneille Ewango, Robin Foster, I. A.U.N. Gunatilleke, C. V.S. Gunatilleke, Pamela Hall, Kyle E. Harms, Terese Hart, Consuelo Hernandez, Stephen Hubbell, Akira Itoh, Somboon Kiratiprayoon, James Lafrankie, Suzanne Loo De Lao, Jean Remy Makana, Md Nur Supardi Noor, Abdul Rahman Kassim, Sabrina Russo, Raman Sukumar, Cristián Samper, Hebbalalu S. Suresh, Sylvester Tan, Sean Thomas, Renato Valencia, Martha Vallejo, Gorky Villa, Tommaso Zillio

Faculty Publications

Most ecological hypotheses about species coexistence hinge on species differences, but quantifying trait differences across species in diverse communities is often unfeasible. We examined the variation of demographic traits using a global tropical forest data set covering 4500 species in 10 large-scale tree inventories. With a hierarchical Bayesian approach, we quantified the distribution Of mortality and growth rates of all tree species at each site. This allowed us to test the prediction that demographic differences facilitate species richness, as suggested by the theory that a tradeoff between high growth and high survival allows species to coexist. Contrary to the prediction, …

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Biocatalytic And Antimetastatic Studies Of The Marine Cembranoids Sarcophine And 2-Epi-16-Deoxysarcophine, Swapnali S. Sawant, Diaa T.A. Youssef, Jane Reiland, Melissa Ferniz, Dario Marchetti, Khalid A. El Sayed Jul 2006

Biocatalytic And Antimetastatic Studies Of The Marine Cembranoids Sarcophine And 2-Epi-16-Deoxysarcophine, Swapnali S. Sawant, Diaa T.A. Youssef, Jane Reiland, Melissa Ferniz, Dario Marchetti, Khalid A. El Sayed

Faculty Publications

The soft coral Sarcophyton glaucum is a rich resource of several bioactive cembranoids. Sarcophytol A (1) and sarcophine (2) are cembranoid diterpenes reported from this soft coral and extensively investigated for their cancer chemopreventive properties. This study aimed at investigating the antimetastatic potential of the major cembranoids, sarcophine (2) and 2-epi-16-deoxysarcophine (3), from the Red Sea soft coral S. glaucum. Biocatalytic transformation of 3 using Rhizopus stolonifer ATCC 6227a and Absidia spinosa ATCC 6648 afforded four new metabolites, 5-7 and 9, along with the known 9α-hydroxysarcophine (8). Sarcophine, 2-epi-16-deoxysarcophine, and metabolites 5-9 revealed significant antimetastatic activity against the highly metastatic …

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Reca And Rada Proteins Of Brucella Abortus Do Not Perform Overlapping Protective Dna Repair Functions Following Oxidative Burst, Christelle M. Roux, Natha J. Booth, Bryan H. Bellaire, Jason M. Gee, R. Martin Roop, Michael E. Kovach, Renée M. Tsolis, Philip H. Elzer, Don G. Ennis Jul 2006

Reca And Rada Proteins Of Brucella Abortus Do Not Perform Overlapping Protective Dna Repair Functions Following Oxidative Burst, Christelle M. Roux, Natha J. Booth, Bryan H. Bellaire, Jason M. Gee, R. Martin Roop, Michael E. Kovach, Renée M. Tsolis, Philip H. Elzer, Don G. Ennis

Faculty Publications

Very little is known about the role of DNA repair networks in Brucella abortus and its role in pathogenesis. We investigated the roles of RecA protein, DNA repair, and SOS regulation in B. abortus. While recA mutants in most bacterial species are hypersensitive to UV damage, surprisingly a B. abortus recA null mutant conferred only modest sensitivity. We considered the presence of a second RecA protein to account for this modest UV sensitivity. Analyses of the Brucella spp. genomes and our molecular studies documented the presence of only one recA gene, suggesting a RecA-independent repair process. Searches of the available …

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Louisiana Agriculture Summer, 2006, Lsu Agcenter Jul 2006

Louisiana Agriculture Summer, 2006, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

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Caliche As A Geological Repository For Atmospheric Sulfate, Katie J. Howell, Huiming Bao Jul 2006

Caliche As A Geological Repository For Atmospheric Sulfate, Katie J. Howell, Huiming Bao

Faculty Publications

Recent studies demonstrate that important information on sulfur source, oxidation pathway, transport pattern, and reaction kinetics of atmospheric oxidation of sulfur gases can be uncovered by measuring multiple isotope compositions of the oxidation product - secondary atmospheric sulfate (SAS). SAS from Earth's distant past, however, is rarely preserved in the rock records because of its high solubility and small quantity. We report here from the measurement of 47 modern and fossil caliche samples that caliches contain variable amounts of carbonate-associated sulfate (CAS), and the Δ17O values of the CAS range from -0.12 to +2.32‰ with most values higher than the …

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Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton Jul 2006

Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton

Faculty Publications

Forest structure and species distribution patterns were examined among eight topographically defined habitats for the 205 species with stems ≥ 1 cm dbh inhabiting a 25-ha plot in the Sinharaja rain forest, Sri Lanka. The habitats were steep spurs, less-steep spurs, steep gullies and less-steep gullies, all at either lower or upper elevations. Mean stem density was significantly greater on the upper spurs than in the lower, less-steep gullies. Stem density was also higher on spurs than in gullies within each elevation category and in each upper-elevation habitat than in its corresponding lower-elevation habitat. Basal area varied less among habitats, …

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A New Species Of Microlepia (Dennstaedtiaceae) From Mt. Micangshan, China, Xiao Si Guo, Bin Li Jul 2006

A New Species Of Microlepia (Dennstaedtiaceae) From Mt. Micangshan, China, Xiao Si Guo, Bin Li

Faculty Publications

A new species, Microlepia micangshanensis (Dennstaedtiaceae), is described and illustrated from the northern slope of Mt. Micangshan in Hanzhong City of Shaanxi Province, China.

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Caliche As A Geological Repository For Atmospheric Sulfate, Katie J. Howell, Huiming Bao Jul 2006

Caliche As A Geological Repository For Atmospheric Sulfate, Katie J. Howell, Huiming Bao

Faculty Publications

Recent studies demonstrate that important information on sulfur source, oxidation pathway, transport pattern, and reaction kinetics of atmospheric oxidation of sulfur gases can be uncovered by measuring multiple isotope compositions of the oxidation product - secondary atmospheric sulfate (SAS). SAS from Earth's distant past, however, is rarely preserved in the rock records because of its high solubility and small quantity. We report here from the measurement of 47 modern and fossil caliche samples that caliches contain variable amounts of carbonate-associated sulfate (CAS), and the Δ17O values of the CAS range from -0.12 to +2.32‰ with most values higher than the …

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The Crystal Structure Of The Transcriptional Regulator Hucr From Deinococcus Radiodurans Reveals A Repressor Preconfigured For Dna Binding, Tee Bordelon, Steven P. Wilkinson, Anne Grove, Marcia E. Newcomer Jun 2006

The Crystal Structure Of The Transcriptional Regulator Hucr From Deinococcus Radiodurans Reveals A Repressor Preconfigured For Dna Binding, Tee Bordelon, Steven P. Wilkinson, Anne Grove, Marcia E. Newcomer

Faculty Publications

We report here the 2.3 Å resolution structure of the hypothetical uricase regulator (HucR) from Deinococcus radiodurans R1. HucR, a member of the MarR family of DNA-binding proteins, was previously shown to repress its own expression as well as that of a uricase, a repression that is alleviated both in vivo and in vitro upon binding uric acid, the substrate for uricase. As uric acid is a potent scavenger of reactive oxygen species, and as D. radiodurans is known for its remarkable resistance to DNA-damaging agents, these observations indicate a novel oxidative stress response mechanism. The crystal structure of HucR …

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Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alptürk, Oleksandr Rusin, Sayo O. Fakayode, Weihua Wang, Jorge O. Escobedo, Isiah M. Warner, William E. Crowe, Vladimir Král, Jeff M. Pruet, Robert M. Strongin Jun 2006

Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alptürk, Oleksandr Rusin, Sayo O. Fakayode, Weihua Wang, Jorge O. Escobedo, Isiah M. Warner, William E. Crowe, Vladimir Král, Jeff M. Pruet, Robert M. Strongin

Faculty Publications

Simple water-soluble lanthanum and europium complexes are effective at detecting neutral sugars as well as glycolipids and phospholipids. In solutions at physiologically relevant pH the fluorescent lanthanum complex binds neutral sugars with apparent binding constants comparable to those of arylboronic acids. Interference from commonly occurring anions is minimal. The europium complex detects sialic acid-containing gangliosides at pH 7.0 over an asialoganglioside. This selectivity is attributed, in large part, to the cooperative complexation of the oligosaccharide and sialic acid residues to the metal center, based on analogous prior studies. In MeOH, lysophosphatidic acid (LPA), a biomarker for several pathological conditions including …

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Is A Shutdown Of The Thermohaline Circulation Irreversible?, Jianjun Yin, Michael E. Schlesinger, Natasha G. Andronova, Sergey Malyshev, Bin Li Jun 2006

Is A Shutdown Of The Thermohaline Circulation Irreversible?, Jianjun Yin, Michael E. Schlesinger, Natasha G. Andronova, Sergey Malyshev, Bin Li

Faculty Publications

The Atlantic thermohaline circulation (THC) plays a vital role in explaining past abrupt climate changes and in maintaining the current climate. Its remarkable nonlinear dynamics, first demonstrated by H. M. Stommel, have been supported by various types of climate models. This has led to severe concerns that global warming may shut down the THC irreversibly, with consequent catastrophic climate changes, particularly for Europe. Here we use an uncoupled ocean general circulation model (OGCM) and a coupled atmosphere-ocean general circulation model (AOGCM) to investigate the nonlinear response of the THC to freshwater perturbations in the northern North Atlantic. We find that …

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Stat5 Activators Modulate Acyl Coa Oxidase (Aox) Expression In Adipocytes And Stat5a Binds To The Aox Promoter In Vitro, Ann A. Coulter, Jacqueline M. Stephens Jun 2006

Stat5 Activators Modulate Acyl Coa Oxidase (Aox) Expression In Adipocytes And Stat5a Binds To The Aox Promoter In Vitro, Ann A. Coulter, Jacqueline M. Stephens

Faculty Publications

Growth hormone (GH) diminishes adipose tissue mass in vivo and prolactin (PRL) can also modulate adipocyte metabolism. Both GH and PRL are potent activators of STAT5 and exert a variety of effects on adipocyte gene expression. In this study, we have demonstrated that GH and PRL increase the mRNA of acyl CoA oxidase in 3T3-L1 adipocytes. We also identified seven putative STAT elements in the murine AOX promoter. We observed that GH modulates protein binding to the majority of these promoter elements. However, GH induced very potent binding to -1841 to -1825 of the murine AOX promoter. EMSA supershift analysis …

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