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Articles 8761 - 8790 of 10791

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Co-Variation In Soil Biodiversity And Biogeochemistry In Northern And Southern Victoria Land, Antarctica, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall, S. C. Cary, A. L. Hacker, J. M. Aislabie Sep 2006

Co-Variation In Soil Biodiversity And Biogeochemistry In Northern And Southern Victoria Land, Antarctica, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall, S. C. Cary, A. L. Hacker, J. M. Aislabie

Faculty Publications

Data from six sites in Victoria Land (72-77degrees S) investigating co-variation in soil communities (microbial and invertebrate) with biogeochemical properties show the influence of soil properties on habitat suitability varied among local landscapes as well as across climate gradients. Species richness of metazoan invertebrates (Nematoda, Tardigrada and Rotifera) was similar to previous descriptions in this region, though identification of three cryptic nematode species of Eudorylaimus through DNA analysis contributed to the understanding of controls over habitat preferences for individual species. Denaturing Gradient Gel Electrophoresis profiles revealed unexpectedly high diversity of bacteria. Distribution of distinct bacterial communities was associated with specific …

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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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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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Dissolved Gallium In The Northwest Pacific And The South And Central Atlantic Oceans: Implications For Aeolian Fe Input And A Reconsideration Of Profiles, Alan M. Shiller, Gautam Raj Bairamadgi Aug 2006

Dissolved Gallium In The Northwest Pacific And The South And Central Atlantic Oceans: Implications For Aeolian Fe Input And A Reconsideration Of Profiles, Alan M. Shiller, Gautam Raj Bairamadgi

Faculty Publications

[1] The distribution of dissolved gallium, a less-reactive analogue of aluminum, has the potential to reveal information about the averaged dust input to the surface ocean and to complement studies using aluminum as a tracer. New data are presented here on the distribution of dissolved Ga, including six profiles in the south and central Atlantic as well as seven shallow and two deep profiles from the northwest Pacific. The Atlantic data allow for an estimate of Ga in Antarctic Bottom Water ( similar to 25 - 30 pmol kg(-1)) and show reasonably conservative behavior in deep waters. In the northwest …

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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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Interaction Of Ice Storms And Management Practices On Current Carbon Sequestration In Forests With Potential Mitigation Under Future Co2 Atmosphere, Heather R. Mccarthy, Ram Oren, Hyun-Seok Kim, Kurt H. Johnsen, Chris Maier, Seth G. Pritchard, Micheal Davis Aug 2006

Interaction Of Ice Storms And Management Practices On Current Carbon Sequestration In Forests With Potential Mitigation Under Future Co2 Atmosphere, Heather R. Mccarthy, Ram Oren, Hyun-Seok Kim, Kurt H. Johnsen, Chris Maier, Seth G. Pritchard, Micheal Davis

Faculty Publications

[1] Ice storms are disturbance events with potential impacts on carbon sequestration. Common forest management practices, such as fertilization and thinning, can change wood and stand properties and thus may change vulnerability to ice storm damage. At the same time, increasing atmospheric CO2 levels may also influence ice storm vulnerability. Here we show that a nonintensively managed pine plantation experienced a ∼250 g C m−2 reduction in living biomass during a single storm, equivalent to ∼30% of the annual net ecosystem carbon exchange of this ecosystem. Drawing on weather and damage survey data from the entire storm cell, …

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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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Empowered Through Labor And Buttressing Their Communities: Mayan Women And Coastal Migration, 1875 - 1965, David Carey Aug 2006

Empowered Through Labor And Buttressing Their Communities: Mayan Women And Coastal Migration, 1875 - 1965, David Carey

Faculty Publications

No abstract provided.

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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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The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie Jul 2006

The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie

Faculty Publications

Calcium-selective ion channels are known to have carboxylate-rich selectivity filters, a common motif that is primarily responsible for their high Ca2+ affinity. Different Ca2+ affinities ranging from micromolar (the L-type Ca channel) to millimolar (the ryanodine receptor channel) are closely related to the different physiological functions of these channels. To understand the physical mechanism for this range of affinities given similar amino acids in their selectivity filters, we use grand canonical Monte Carlo simulations to assess the binding of monovalent and divalent ions in the selectivity filter of a model Ca channel. We use a reduced model where the electrolyte …

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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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Reexamining Relational Youth Ministry: Implications From The Theology Of Bonhoeffer, Andrew Root Jul 2006

Reexamining Relational Youth Ministry: Implications From The Theology Of Bonhoeffer, Andrew Root

Faculty Publications

Youth ministry often focuses on building relationships between youth ministers and adolescents. But to what end? A relationship designed to influence the other is no relationship and is unworthy of Christ. In a true relationship Christians must be willing fully to share the place of another.

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Incorporating Policymaker Costs And Political Competition Into Rent-Seeking Games, R. Kenneth Godwin, Edward J. Lopez, Barry J. Seldon Jul 2006

Incorporating Policymaker Costs And Political Competition Into Rent-Seeking Games, R. Kenneth Godwin, Edward J. Lopez, Barry J. Seldon

Faculty Publications

We incorporate policymaker costs of supplying rents and variable intensities of competition among rent seekers into the standard rent-seeking game. By incorporating these aspects, the game has greater verisimilitude to the lobbying process. The first aspect captures the fact that in rent-seeking contests there is a positive probability that neither firm will obtain the rent. The second aspect captures the fact that firms seeking different rents still must compete for policymakers' resources. We find that lobbying expenditures, rent-seeking profits, and rent dissipation depend on the intensity of competition and the value of the rent relative to policymaker costs. For example, …

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Ecological Fitting As A Determinant Of The Community Structure Of Platyhelminth Parasites Of Anurans, Daniel R. Brooks, Virginia León-Règagnon, Deborah Mclennan, Derek Zelmer Jul 2006

Ecological Fitting As A Determinant Of The Community Structure Of Platyhelminth Parasites Of Anurans, Daniel R. Brooks, Virginia León-Règagnon, Deborah Mclennan, Derek Zelmer

Faculty Publications

Host–parasite associations are assumed to be ecologically specialized, tightly coevolved systems driven by mutual modification in which host switching is a rare phenomenon. Ecological fitting, however, increases the probability of host switching, creating incongruences between host and parasite phylogenies, when (1) specialization on a particular host resource is a shared characteristic of distantly related parasites, and (2) the resource being tracked by the parasite is widespread among many host species. We investigated the effect of ecological fitting on structuring the platyhelminth communities of anurans from a temperate forest and grassland in the United States and tropical dry and wet forests …

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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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