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Sample records for plants iii distribution

  1. Comparative Studies on Plastoquinones. III. Distribution of Plastoquinones in Higher Plants 1

    PubMed Central

    Barr, Rita; Crane, F. L.

    1967-01-01

    The distribution of plastoquinones A 45, B and C was studied in representatives from 34 different plant families beginning with liverworts and mosses to higher plants. All of these species, including many monocots and dicots, contained significant amounts of the 3 quinones. Two species of Aesculus contained plastoquinone A 20 in addition to plastoquinone A 45, B, and C. Many dicots, such as Aesculus, watermelon, tobacco and tomato accumulated increasing quantities of plastoquinones A and C1-C4 during the growing season. The concentrations of plastoquinones B and C5-C6 tended to remain at a constant low level during the season (<0.01 μmole per mg chlorophyll). Preliminary studies with bean plants (Vicia faba and Phaseolus sp.) indicate that the levels of quinones varied little under different growth conditions (day length and temp.) although Vicia faba tended to have higher PQ A values with increased temperature. PMID:16656647

  2. Power plant III - Steam

    NASA Astrophysics Data System (ADS)

    Roche, M.

    The projected principal components, performance, and costs associated with a direct cycle steam generating solar thermal power plant producing over 10 MWe are examined. Calculations are given for a location in south France, using heliostat and heat exchanger technology developed for Themis. The heat exchanger would have vertical tubes on the side walls for natural circulation, with superheater channels at the top composed of austenitic steels. Temperature of the superheated steam could be regulated by injections of liquid water. Maintaining the pressure during the passage of clouds is taken to require the presence of an auxiliary boiler burning fossil fuels, since no method is presently known of storing latent heat at over 300 C. Approaching clouds would have to be detected in order to stop the heliostats and ignite the back-up systems.

  3. BES-III distributed computing status

    NASA Astrophysics Data System (ADS)

    Belov, S. D.; Deng, Z. Y.; Korenkov, V. V.; Li, W. D.; Lin, T.; Ma, Z. T.; Nicholson, C.; Pelevanyuk, I. S.; Suo, B.; Trofimov, V. V.; Tsaregorodtsev, A. U.; Uzhinskiy, A. V.; Yan, T.; Yan, X. F.; Zhang, X. M.; Zhemchugov, A. S.

    2016-09-01

    The BES-III experiment at the Institute of High Energy Physics (Beijing, China) is aimed at the precision measurements in e+e- annihilation in the energy range from 2.0 till 4.6 GeV. The world's largest samples of J/psi and psi' events and unique samples of XYZ data have been already collected. The expected increase of the data volume in the coming years required a significant evolution of the computing model, namely shift from a centralized data processing to a distributed one. This report summarizes a current design of the BES-III distributed computing system, some of key decisions and experience gained during 2 years of operations.

  4. Using a dual-stable isotope tracer method to study the uptake, xylem transport and distribution of Fe and its chelating agent from stereoisomers of an Fe(III)-chelate used as fertilizer in Fe-deficient Strategy I plants.

    PubMed

    Orera, Irene; Rodríguez-Castrillón, José A; Moldovan, Mariella; García-Alonso, José I; Abadía, Anunciación; Abadía, Javier; Alvarez-Fernández, Ana

    2010-09-01

    A dual-stable isotope tracer experiment was carried out with Fe-deficient sugar beet plants grown hydroponically and resupplied with differentially Fe labeled racemic and meso Fe(iii)-chelates of the ethylendiamine di(o-hydroxyphenylacetic) acid (o,oEDDHA). No short-term Fe isotope exchange reactions occurred in the nutrient solution and plants did not discriminate between (54)Fe and (57)Fe. After 3-6 h, stable Fe isotopes, chelating agents and chelates were analyzed in roots, xylem sap and leaves by ICP-MS and HPLC-ESI/TOFMS. Ferric chelate reductase rates, xylem transport and total uptake were 2-fold higher with the meso isomer than with the racemic one. Both chelating agent isomers were incorporated and distributed by plants at similar rates, in amounts one order of magnitude lower than those of Fe. After 6 h of Fe resupply, most of the Fe acquired was localized in roots, whereas most of the chelating agent was in leaves. In a separate experiment, Fe-deficient sugar beet and tomato plants were treated with different concentrations of Fe(iii)-o,oEDDHA (with a meso/racemic ratio of 1). The xylem sap Fe concentration at 24 h was unaffected by the chelate concentration, with xylem Fe(iii)-o,oEDDHA accounting for 1-18% of total Fe and xylem meso/racemic ratio close to 1. Although most of the Fe coming from Fe(iii)-o,oEDDHA was taken up through a reductive dissociative mechanism, a small part of the Fe may be taken up via non-dissociative mechanisms. PMID:21072356

  5. The NATO III 5 MHz Distribution System

    NASA Technical Reports Server (NTRS)

    Vulcan, A.; Bloch, M.

    1981-01-01

    A high performance 5 MHz distribution system is described which has extremely low phase noise and jitter characteristics and provides multiple buffered outputs. The system is completely redundant with automatic switchover and is self-testing. Since the 5 MHz reference signals distributed by the NATO III distribution system are used for up-conversion and multiplicative functions, a high degree of phase stability and isolation between outputs is necessary. Unique circuit design and packaging concepts insure that the isolation between outputs is sufficient to quarantee a phase perturbation of less than 0.0016 deg when other outputs are open circuited, short circuited or terminated in 50 ohms. Circuit design techniques include high isolation cascode amplifiers. Negative feedback stabilizes system gain and minimizes circuit phase noise contributions. Balanced lines, in lieu of single ended coaxial transmission media, minimize pickup.

  6. Acetylcholine as a signaling system to environmental stimuli in plants. III. Asymmetric solute distribution controlled by ACh in gravistimulated maize seedlings.

    PubMed

    Momonoki, Y S; Hineno, C; Noguchi, K

    1998-01-01

    Asymmetric distribution of acetylcholinesterase (AChE) activity has previously been demonstrated to occur in the lower side of the gravity-stimulated maize shoot. The localization of immunoreacted IAA-inositol synthase, AChE and safranin was detected in selected organs of gravistimulated dark grown maize seedlings using a light microscope. Immunoreacted IAA-inositol synthase was asymmetrically distributed in the lower side of the stele of coleoptile node and mesocotyl in maize seedlings placed horizontally. The positive AChE spots in the coleoptile node and mesocotyl were apparently localized in the lower half of the gravistimulated seedlings. Safranin was also asymmetrically distributed in the lower half of the endodermis and stele cells of coleoptile node and mesocotyl. Namely, transport of safranin in the upper half of the coleoptile node and mesocotyl was blocked by gravistimulation. Furthermore, the asymmetric distribution of immunoreacted IAA-inositol synthase was inhibited by neostigmine bromide, AChE inhibitor. These results show that an asymmetric environmental stimulus induces changes in AChE activity, affecting IAA-inositol synthase localization and safranin transport. PMID:12162322

  7. Plotting Formula for Pearson Type III Distribution Considering Historical Information.

    ERIC Educational Resources Information Center

    Nguyen, Van Thanh-Van; In-na, Nophadol

    1992-01-01

    Proposes a plotting position formula for the Pearson type III distribution in the analysis of historical flood information. Presents results of a numerical example using actual flood data to confirm the appropriateness of the plotting formula. (24 references) (MDH)

  8. 7 CFR 1000.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1000.5 Section 1000.5 Agriculture... Definitions § 1000.5 Distributing plant. Distributing plant means a plant that is approved by a duly... plants....

  9. 7 CFR 1000.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1000.5 Section 1000.5 Agriculture... Definitions § 1000.5 Distributing plant. Distributing plant means a plant that is approved by a duly... plants....

  10. 7 CFR 1000.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1000.5 Section 1000.5 Agriculture... Definitions § 1000.5 Distributing plant. Distributing plant means a plant that is approved by a duly... plants....

  11. 7 CFR 1000.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1000.5 Section 1000.5 Agriculture... Definitions § 1000.5 Distributing plant. Distributing plant means a plant that is approved by a duly... plants....

  12. 7 CFR 1000.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1000.5 Section 1000.5 Agriculture... Definitions § 1000.5 Distributing plant. Distributing plant means a plant that is approved by a duly... plants....

  13. Phytopathogen type III effector weaponry and their plant targets

    PubMed Central

    Block, Anna; Li, Guangyong; Fu, Zheng Qing; Alfano, James R.

    2008-01-01

    Summary Phytopathogenic bacteria suppress plant innate immunity and promote pathogenesis by injecting proteins called type III effectors into plant cells using a type III protein secretion system. These type III effectors use at least three major strategies to alter host responses. One strategy is to alter host protein turnover, either by direct cleavage or by modulating ubiquitination and targeting to the 26S proteasome. Another strategy involves alteration of RNA metabolism by transcriptional activation or ADP-ribosylation of RNA-binding proteins. A third major strategy is to inhibit the kinases involved in plant defence signalling, either by removing phosphates or by direct inhibition. The wide array of strategies bacterial pathogens employ to suppress innate immunity suggest that circumvention of innate immunity is critical for bacterial pathogenicity of plants. PMID:18657470

  14. PeroxiBase: a class III plant peroxidase database.

    PubMed

    Bakalovic, Nenad; Passardi, Filippo; Ioannidis, Vassilios; Cosio, Claudia; Penel, Claude; Falquet, Laurent; Dunand, Christophe

    2006-03-01

    Class III plant peroxidases (EC 1.11.1.7), which are encoded by multigenic families in land plants, are involved in several important physiological and developmental processes. Their varied functions are not yet clearly determined, but their characterization will certainly lead to a better understanding of plant growth, differentiation and interaction with the environment, and hence to many exciting applications. Since there is currently no central database for plant peroxidase sequences and many plant sequences are not deposited in the EMBL/GenBank/DDBJ repository or the UniProt KnowledgeBase, this prevents researchers from easily accessing all peroxidase sequences. Furthermore, gene expression data are poorly covered and annotations are inconsistent. In this rapidly moving field, there is a need for continual updating and correction of the peroxidase superfamily in plants. Moreover, consolidating information about peroxidases will allow for comparison of peroxidases between species and thus significantly help making correlations of function, structure or phylogeny. We report a new database (PeroxiBase) accessible through a web server with specific tools dedicated to facilitate query, classification and submission of peroxidase sequences. Recent developments in the field of plant peroxidase are also mentioned.

  15. 7 CFR 1126.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1126.5 Section 1126.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1126.5 Distributing plant. See § 1000.5....

  16. 7 CFR 1032.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1032.5 Section 1032.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1032.5 Distributing plant. See § 1000.5....

  17. 7 CFR 1131.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1131.5 Section 1131.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1131.5 Distributing plant. See § 1000.5....

  18. 7 CFR 1006.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1006.5 Section 1006.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1006.5 Distributing plant. See § 1000.5....

  19. 7 CFR 1005.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1005.5 Section 1005.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1005.5 Distributing plant. See § 1000.5....

  20. 7 CFR 1007.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1007.5 Section 1007.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.5 Distributing plant. See § 1000.5....

  1. 7 CFR 1131.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1131.5 Section 1131.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.5 Distributing plant. See § 1000.5....

  2. 7 CFR 1124.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1124.5 Section 1124.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Definitions § 1124.5 Distributing plant. See § 1000.5....

  3. 7 CFR 1124.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1124.5 Section 1124.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.5 Distributing plant. See § 1000.5....

  4. 7 CFR 1001.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1001.5 Section 1001.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1001.5 Distributing plant. See § 1000.5....

  5. 7 CFR 1131.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1131.5 Section 1131.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1131.5 Distributing plant. See § 1000.5....

  6. 7 CFR 1007.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1007.5 Section 1007.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1007.5 Distributing plant. See § 1000.5....

  7. 7 CFR 1032.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1032.5 Section 1032.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1032.5 Distributing plant. See § 1000.5....

  8. 7 CFR 1126.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1126.5 Section 1126.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.5 Distributing plant. See § 1000.5....

  9. 7 CFR 1033.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1033.5 Section 1033.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1033.5 Distributing plant. See § 1000.5....

  10. 7 CFR 1005.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1005.5 Section 1005.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1005.5 Distributing plant. See § 1000.5....

  11. 7 CFR 1124.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1124.5 Section 1124.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Definitions § 1124.5 Distributing plant. See § 1000.5....

  12. 7 CFR 1126.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1126.5 Section 1126.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1126.5 Distributing plant. See § 1000.5....

  13. 7 CFR 1033.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1033.5 Section 1033.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1033.5 Distributing plant. See § 1000.5....

  14. 7 CFR 1001.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1001.5 Section 1001.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.5 Distributing plant. See § 1000.5....

  15. 7 CFR 1030.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1030.5 Section 1030.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1030.5 Distributing plant. See § 1000.5....

  16. 7 CFR 1007.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1007.5 Section 1007.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1007.5 Distributing plant. See § 1000.5....

  17. 7 CFR 1006.5 - Distributing plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Distributing plant. 1006.5 Section 1006.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1006.5 Distributing plant. See § 1000.5....

  18. 7 CFR 1033.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1033.5 Section 1033.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.5 Distributing plant. See § 1000.5....

  19. 7 CFR 1030.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1030.5 Section 1030.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1030.5 Distributing plant. See § 1000.5....

  20. 7 CFR 1006.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1006.5 Section 1006.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.5 Distributing plant. See § 1000.5....

  1. 7 CFR 1001.5 - Distributing plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Distributing plant. 1001.5 Section 1001.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1001.5 Distributing plant. See § 1000.5....

  2. 7 CFR 1005.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1005.5 Section 1005.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.5 Distributing plant. See § 1000.5....

  3. 7 CFR 1032.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1032.5 Section 1032.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.5 Distributing plant. See § 1000.5....

  4. 7 CFR 1030.5 - Distributing plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Distributing plant. 1030.5 Section 1030.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.5 Distributing plant. See § 1000.5....

  5. 7 CFR 1131.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1131.5 Section 1131.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.5 Distributing plant. See § 1000.5....

  6. 7 CFR 1126.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1126.5 Section 1126.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.5 Distributing plant. See § 1000.5....

  7. 7 CFR 1124.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1124.5 Section 1124.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.5 Distributing plant. See § 1000.5....

  8. 7 CFR 1030.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1030.5 Section 1030.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.5 Distributing plant. See § 1000.5....

  9. 7 CFR 1007.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1007.5 Section 1007.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.5 Distributing plant. See § 1000.5....

  10. 7 CFR 1007.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1007.5 Section 1007.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.5 Distributing plant. See § 1000.5....

  11. 7 CFR 1032.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1032.5 Section 1032.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.5 Distributing plant. See § 1000.5....

  12. 7 CFR 1033.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1033.5 Section 1033.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.5 Distributing plant. See § 1000.5....

  13. 7 CFR 1001.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1001.5 Section 1001.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.5 Distributing plant. See § 1000.5....

  14. 7 CFR 1126.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1126.5 Section 1126.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.5 Distributing plant. See § 1000.5....

  15. 7 CFR 1006.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1006.5 Section 1006.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.5 Distributing plant. See § 1000.5....

  16. 7 CFR 1006.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1006.5 Section 1006.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.5 Distributing plant. See § 1000.5....

  17. 7 CFR 1032.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1032.5 Section 1032.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.5 Distributing plant. See § 1000.5....

  18. 7 CFR 1033.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1033.5 Section 1033.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.5 Distributing plant. See § 1000.5....

  19. 7 CFR 1124.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1124.5 Section 1124.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.5 Distributing plant. See § 1000.5....

  20. 7 CFR 1030.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1030.5 Section 1030.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.5 Distributing plant. See § 1000.5....

  1. 7 CFR 1001.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1001.5 Section 1001.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.5 Distributing plant. See § 1000.5....

  2. 7 CFR 1005.5 - Distributing plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Distributing plant. 1005.5 Section 1005.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.5 Distributing plant. See § 1000.5....

  3. 7 CFR 1005.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1005.5 Section 1005.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.5 Distributing plant. See § 1000.5....

  4. 7 CFR 1131.5 - Distributing plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Distributing plant. 1131.5 Section 1131.5 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.5 Distributing plant. See § 1000.5....

  5. Herbivory: effects on plant abundance, distribution and population growth

    PubMed Central

    Maron, John L; Crone, Elizabeth

    2006-01-01

    Plants are attacked by many different consumers. A critical question is how often, and under what conditions, common reductions in growth, fecundity or even survival that occur due to herbivory translate to meaningful impacts on abundance, distribution or dynamics of plant populations. Here, we review population-level studies of the effects of consumers on plant dynamics and evaluate: (i) whether particular consumers have predictably more or less influence on plant abundance, (ii) whether particular plant life-history types are predictably more vulnerable to herbivory at the population level, (iii) whether the strength of plant–consumer interactions shifts predictably across environmental gradients and (iv) the role of consumers in influencing plant distributional limits. Existing studies demonstrate numerous examples of consumers limiting local plant abundance and distribution. We found larger effects of consumers on grassland than woodland forbs, stronger effects of herbivory in areas with high versus low disturbance, but no systematic or unambiguous differences in the impact of consumers based on plant life-history or herbivore feeding mode. However, our ability to evaluate these and other patterns is limited by the small (but growing) number of studies in this area. As an impetus for further study, we review strengths and challenges of population-level studies, such as interpreting net impacts of consumers in the presence of density dependence and seed bank dynamics. PMID:17002942

  6. Behind the lines–actions of bacterial type III effector proteins in plant cells

    PubMed Central

    Büttner, Daniela

    2016-01-01

    Pathogenicity of most Gram-negative plant-pathogenic bacteria depends on the type III secretion (T3S) system, which translocates bacterial effector proteins into plant cells. Type III effectors modulate plant cellular pathways to the benefit of the pathogen and promote bacterial multiplication. One major virulence function of type III effectors is the suppression of plant innate immunity, which is triggered upon recognition of pathogen-derived molecular patterns by plant receptor proteins. Type III effectors also interfere with additional plant cellular processes including proteasome-dependent protein degradation, phytohormone signaling, the formation of the cytoskeleton, vesicle transport and gene expression. This review summarizes our current knowledge on the molecular functions of type III effector proteins with known plant target molecules. Furthermore, plant defense strategies for the detection of effector protein activities or effector-triggered alterations in plant targets are discussed. PMID:27526699

  7. Distribution Integrity Management Plant (DIMP)

    SciTech Connect

    Gonzales, Jerome F.

    2012-05-07

    This document is the distribution integrity management plan (Plan) for the Los Alamos National Laboratory (LANL) Natural Gas Distribution System. This Plan meets the requirements of 49 CFR Part 192, Subpart P Distribution Integrity Management Programs (DIMP) for the LANL Natural Gas Distribution System. This Plan was developed by reviewing records and interviewing LANL personnel. The records consist of the design, construction, operation and maintenance for the LANL Natural Gas Distribution System. The records system for the LANL Natural Gas Distribution System is limited, so the majority of information is based on the judgment of LANL employees; the maintenance crew, the Corrosion Specialist and the Utilities and Infrastructure (UI) Civil Team Leader. The records used in this report are: Pipeline and Hazardous Materials Safety Administration (PHMSA) 7100.1-1, Report of Main and Service Line Inspection, Natural Gas Leak Survey, Gas Leak Response Report, Gas Leak and Repair Report, and Pipe-to-Soil Recordings. The specific elements of knowledge of the infrastructure used to evaluate each threat and prioritize risks are listed in Sections 6 and 7, Threat Evaluation and Risk Prioritization respectively. This Plan addresses additional information needed and a method for gaining that data over time through normal activities. The processes used for the initial assessment of Threat Evaluation and Risk Prioritization are the methods found in the Simple, Handy Risk-based Integrity Management Plan (SHRIMP{trademark}) software package developed by the American Pipeline and Gas Agency (APGA) Security and Integrity Foundation (SIF). SHRIMP{trademark} uses an index model developed by the consultants and advisors of the SIF. Threat assessment is performed using questions developed by the Gas Piping Technology Company (GPTC) as modified and added to by the SHRIMP{trademark} advisors. This Plan is required to be reviewed every 5 years to be continually refined and improved. Records

  8. Microbial As(III) Oxidation in Water Treatment Plant Filters

    EPA Science Inventory

    Arsenic exists in two oxidation states in water - arsenite [As(III)] and arsenate [As(V)]. As(III) is relatively mobile in water and difficult to remove by arsenic-removal treatment processes. Source waters that contain As(III) must add a strong oxidant such as free chlorine or p...

  9. Diverse evolutionary mechanisms shape the type III effector virulence factor repertoire in the plant pathogen Pseudomonas syringae.

    PubMed Central

    Rohmer, Laurence; Guttman, David S; Dangl, Jeffery L

    2004-01-01

    Many gram-negative pathogenic bacteria directly translocate effector proteins into eukaryotic host cells via type III delivery systems. Type III effector proteins are determinants of virulence on susceptible plant hosts; they are also the proteins that trigger specific disease resistance in resistant plant hosts. Evolution of type III effectors is dominated by competing forces: the likely requirement for conservation of virulence function, the avoidance of host defenses, and possible adaptation to new hosts. To understand the evolutionary history of type III effectors in Pseudomonas syringae, we searched for homologs to 44 known or candidate P. syringae type III effectors and two effector chaperones. We examined 24 gene families for distribution among bacterial species, amino acid sequence diversity, and features indicative of horizontal transfer. We assessed the role of diversifying and purifying selection in the evolution of these gene families. While some P. syringae type III effectors were acquired recently, others have evolved predominantly by descent. The majority of codons in most of these genes were subjected to purifying selection, suggesting selective pressure to maintain presumed virulence function. However, members of 7 families had domains subject to diversifying selection. PMID:15280247

  10. EM algorithm in estimating the 2- and 3-parameter Burr Type III distributions

    NASA Astrophysics Data System (ADS)

    Ismail, Nor Hidayah Binti; Khalid, Zarina Binti Mohd

    2014-07-01

    The Burr Type III distribution has been applied in the study of income, wage and wealth. It is suitable to fit lifetime data since it has flexible shape and controllable scale parameters. The popularity of Burr Type III distribution increases because it has included the characteristics of other distributions such as logistic and exponential. Burr Type III distribution has two categories: First a two-parameter distribution which has two shape parameters and second a three-parameter distribution which has a scale and two shape parameters. Expectation-maximization (EM) algorithm method is selected in this paper to estimate the two- and three-parameter Burr Type III distributions. Complete and censored data are simulated based on the derivation of pdf and cdf in parametric form of Burr Type III distributions. Then, the EM estimates are compared with estimates from maximum likelihood estimation (MLE) approach through mean square error. The best approach results in estimates with a higher approximation to the true parameters are determined. The result shows that the EM algorithm estimates perform better than the MLE estimates for two- and three-parameter Burr Type III distributions in the presence of complete and censored data.

  11. ERTS-1 imagery and native plant distributions

    NASA Technical Reports Server (NTRS)

    Musick, H. B.; Mcginnies, W.; Haase, E.; Lepley, L. K.

    1974-01-01

    A method is developed for using ERTS spectral signature data to determine plant community distribution and phenology without resolving individual plants. An Exotech ERTS radiometer was used near ground level to obtain spectral signatures for a desert plant community, including two shrub species, ground covered with live annuals in April and dead ones in June, and bare ground. It is shown that comparisons of scene types can be made when spectral signatures are expressed as a ratio of red reflectivity to IR reflectivity or when they are plotted as red reflectivity vs. IR reflectivity, in which case the signature clusters of each component are more distinct. A method for correcting and converting the ERTS radiance values to reflectivity values for comparison with ground truth data is appended.

  12. Comparative physiology of elemental distributions in plants

    PubMed Central

    Conn, Simon; Gilliham, Matthew

    2010-01-01

    Background Plants contain relatively few cell types, each contributing a specialized role in shaping plant function. With respect to plant nutrition, different cell types accumulate certain elements in varying amounts within their storage vacuole. The role and mechanisms underlying cell-specific distribution of elements in plants is poorly understood. Scope The phenomenon of cell-specific elemental accumulation has been briefly reviewed previously, but recent technological advances with the potential to probe mechanisms underlying elemental compartmentation have warranted an updated evaluation. We have taken this opportunity to catalogue many of the studies, and techniques used for, recording cell-specific compartmentation of particular elements. More importantly, we use three case-study elements (Ca, Cd and Na) to highlight the basis of such phenomena in terms of their physiological implications and underpinning mechanisms; we also link such distributions to the expression of known ion or solute transporters. Conclusions Element accumulation patterns are clearly defined by expression of key ion or solute transporters. Although the location of element accumulation is fairly robust, alterations in expression of certain solute transporters, through genetic modifications or by growth under stress, result in perturbations to these patterns. However, redundancy or induced pleiotropic expression effects may complicate attempts to characterize the pathways that lead to cell-specific elemental distribution. Accumulation of one element often has consequences on the accumulation of others, which seems to be driven largely to maintain vacuolar and cytoplasmic osmolarity and charge balance, and also serves as a detoxification mechanism. Altered cell-specific transcriptomics can be shown, in part, to explain some of this compensation. PMID:20410048

  13. Presence of unique glyoxalase III proteins in plants indicates the existence of shorter route for methylglyoxal detoxification

    PubMed Central

    Ghosh, Ajit; Kushwaha, Hemant R; Hasan, Mohammad R; Pareek, Ashwani; Sopory, Sudhir K; Singla-Pareek, Sneh L

    2016-01-01

    Glyoxalase pathway, comprising glyoxalase I (GLY I) and glyoxalase II (GLY II) enzymes, is the major pathway for detoxification of methylglyoxal (MG) into D-lactate involving reduced glutathione (GSH). However, in bacteria, glyoxalase III (GLY III) with DJ-1/PfpI domain(s) can do the same conversion in a single step without GSH. Our investigations for the presence of DJ-1/PfpI domain containing proteins in plants have indicated the existence of GLY III-like proteins in monocots, dicots, lycopods, gymnosperm and bryophytes. A deeper in silico analysis of rice genome identified twelve DJ-1 proteins encoded by six genes. Detailed analysis has been carried out including their chromosomal distribution, genomic architecture and localization. Transcript profiling under multiple stress conditions indicated strong induction of OsDJ-1 in response to exogenous MG. A member of OsDJ-1 family, OsDJ-1C, showed high constitutive expression at all developmental stages and tissues of rice. MG depletion study complemented by simultaneous formation of D-lactate proved OsDJ-1C to be a GLY III enzyme that converts MG directly into D-lactate in a GSH-independent manner. Site directed mutagenesis of Cys-119 to Alanine significantly reduces its GLY III activity indicating towards the existence of functional GLY III enzyme in rice—a shorter route for MG detoxification. PMID:26732528

  14. Presence of unique glyoxalase III proteins in plants indicates the existence of shorter route for methylglyoxal detoxification.

    PubMed

    Ghosh, Ajit; Kushwaha, Hemant R; Hasan, Mohammad R; Pareek, Ashwani; Sopory, Sudhir K; Singla-Pareek, Sneh L

    2016-01-01

    Glyoxalase pathway, comprising glyoxalase I (GLY I) and glyoxalase II (GLY II) enzymes, is the major pathway for detoxification of methylglyoxal (MG) into D-lactate involving reduced glutathione (GSH). However, in bacteria, glyoxalase III (GLY III) with DJ-1/PfpI domain(s) can do the same conversion in a single step without GSH. Our investigations for the presence of DJ-1/PfpI domain containing proteins in plants have indicated the existence of GLY III-like proteins in monocots, dicots, lycopods, gymnosperm and bryophytes. A deeper in silico analysis of rice genome identified twelve DJ-1 proteins encoded by six genes. Detailed analysis has been carried out including their chromosomal distribution, genomic architecture and localization. Transcript profiling under multiple stress conditions indicated strong induction of OsDJ-1 in response to exogenous MG. A member of OsDJ-1 family, OsDJ-1C, showed high constitutive expression at all developmental stages and tissues of rice. MG depletion study complemented by simultaneous formation of D-lactate proved OsDJ-1C to be a GLY III enzyme that converts MG directly into D-lactate in a GSH-independent manner. Site directed mutagenesis of Cys-119 to Alanine significantly reduces its GLY III activity indicating towards the existence of functional GLY III enzyme in rice-a shorter route for MG detoxification. PMID:26732528

  15. Stability of Tl(III) in the context of speciation analysis of thallium in plants.

    PubMed

    Sadowska, Monika; Biaduń, Ewa; Krasnodębska-Ostręga, Beata

    2016-02-01

    The paper presents both "good" and "bad" results obtained during speciation analysis of thallium in plant tissues of a hyperaccumulator of this metal. The object was white mustard - Sinapis alba L. In this plant there were found traces of trivalent thallium. The crucial point of this study (especially in the case of so unstable thallium form as Tl(III)) was to prove that the presence of Tl(III) was not caused by the procedure of sample preparation itself, and that the whole analytical method provides reliable results. Choice of the method for conservation of the initial speciation, extraction with the highest efficiency and proving the correctness of the obtained data were the most difficult parts of the presented study. It was found that: both freezing and drying cause significant changes in the speciation of thallium; quantitative analysis could be performed only with fresh tissues of mustard plants; only short-term storage of an extract from fresh plant tissues is possible; the methodology is not the source of thallium (III); only the presence of DTPA can greatly limit the reduction of TI(III) to TI(I) (up to 1-3%); the UV irradiation results in disintegration of TI(III)DTPA in the presence of plant matrix (reduction up to 90%). PMID:26465967

  16. Stability of Tl(III) in the context of speciation analysis of thallium in plants.

    PubMed

    Sadowska, Monika; Biaduń, Ewa; Krasnodębska-Ostręga, Beata

    2016-02-01

    The paper presents both "good" and "bad" results obtained during speciation analysis of thallium in plant tissues of a hyperaccumulator of this metal. The object was white mustard - Sinapis alba L. In this plant there were found traces of trivalent thallium. The crucial point of this study (especially in the case of so unstable thallium form as Tl(III)) was to prove that the presence of Tl(III) was not caused by the procedure of sample preparation itself, and that the whole analytical method provides reliable results. Choice of the method for conservation of the initial speciation, extraction with the highest efficiency and proving the correctness of the obtained data were the most difficult parts of the presented study. It was found that: both freezing and drying cause significant changes in the speciation of thallium; quantitative analysis could be performed only with fresh tissues of mustard plants; only short-term storage of an extract from fresh plant tissues is possible; the methodology is not the source of thallium (III); only the presence of DTPA can greatly limit the reduction of TI(III) to TI(I) (up to 1-3%); the UV irradiation results in disintegration of TI(III)DTPA in the presence of plant matrix (reduction up to 90%).

  17. DOE-EPRI distributed wind Turbine Verification Program (TVP III)

    SciTech Connect

    McGowin, C.; DeMeo, E.; Calvert, S.

    1997-12-31

    In 1992, the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE) initiated the Utility Wind Turbine Verification Program (TVP). The goal of the program is to evaluate prototype advanced wind turbines at several sites developed by U.S. electric utility companies. Two six MW wind projects have been installed under the TVP program by Central and South West Services in Fort Davis, Texas and Green Mountain Power Corporation in Searsburg, Vermont. In early 1997, DOE and EPRI selected five more utility projects to evaluate distributed wind generation using smaller {open_quotes}clusters{close_quotes} of wind turbines connected directly to the electricity distribution system. This paper presents an overview of the objectives, scope, and status of the EPRI-DOE TVP program and the existing and planned TVP projects.

  18. Removal of arsenic(III) from aqueous solutions using fresh and immobilized plant biomass.

    PubMed

    Kamala, C T; Chu, K H; Chary, N S; Pandey, P K; Ramesh, S L; Sastry, A R K; Sekhar, K Chandra

    2005-08-01

    The ability of Garcinia cambogia, an indigenous plant found in many parts of India, to remove trivalent arsenic from solution was assessed. Batch experiments were carried out to characterize the As(III) removal capability of fresh and immobilized biomass of G. cambogia. It was found that the kinetic property and uptake capacity of fresh biomass were significantly enhanced by the immobilization procedure. The uptake of As(III) by fresh and immobilized biomass was not greatly affected by solution pH with optimal biosorption occurring at around pH 6--8. The presence of common ions such as Ca and Mg at concentrations up to 100mg/l had no effect on As(III) removal. However, the presence of Fe(III) at 100mg/l caused a noticeable drop in the extent of As(III) removal but the effect was minimal when Fe(III) was present at 10mg/l. The adsorption isotherms quantitatively predicted the extent of As(III) removal in groundwater samples collected from an arsenic-contaminated site in India. Immobilized biomass loaded with As(III) was amenable to efficient regeneration with NaOH solution. Column studies showed that immobilized biomass could be reused over five cycles of loading and elution. The excellent As(III) sequestering capability of fresh and immobilized G. cambogia biomass could lead to the development of a viable and cost-effective technology for arsenic removal in groundwater. PMID:15993920

  19. Part III: AFS - A Secure Distributed File System

    SciTech Connect

    Wachsmann, A.; /SLAC

    2005-06-29

    AFS is a secure distributed global file system providing location independence, scalability and transparent migration capabilities for data. AFS works across a multitude of Unix and non-Unix operating systems and is used at many large sites in production for many years. AFS still provides unique features that are not available with other distributed file systems even though AFS is almost 20 years old. This age might make it less appealing to some but with IBM making AFS available as open-source in 2000, new interest in use and development was sparked. When talking about AFS, people often mention other file systems as potential alternatives. Coda (http://www.coda.cs.cmu.edu/) with its disconnected mode will always be a research project and never have production quality. Intermezzo (http://www.inter-mezzo.org/) is now in the Linux kernel but not available for any other operating systems. NFSv4 (http://www.nfsv4.org/) which picked up many ideas from AFS and Coda is not mature enough yet to be used in serious production mode. This article presents the rich features of AFS and invites readers to play with it.

  20. Custom impression trays. Part III: A stress distribution model.

    PubMed

    Moseley, J P; Dixon, D L; Breeding, L C

    1994-05-01

    All resins used to make custom impression trays exhibit plastic deformation at some force value; therefore it is important to compare the physical property values of such materials with the stresses to which impression trays are subjected during dental procedures. A simple mathematical model of a custom tray was developed to predict stress distributions in this final part of a three-part investigation. Experimental stress analysis of such a tray confirmed the accuracy of the model, which was then used to predict the maximum stress experienced by the tray during removal of a completed impression from the oral cavity. The results of this analysis indicated that these stresses would be significantly lower than the yield stress for a commonly used polymethyl methacrylate resin or a light-polymerized resin. The stresses were also sufficiently low for us to conclude that thermoplastic resins would not permanently deform; however, the stresses encountered in the experimental confirmation procedure were close to the yield stress values for these materials.

  1. TYPE III RADIO BURSTS IN CORONAL PLASMAS WITH KAPPA PARTICLE DISTRIBUTIONS

    SciTech Connect

    Li, B.; Cairns, Iver H.

    2013-02-01

    We present the first simulations of type III bursts produced in the corona with suprathermal non-Maxwellian background particles, as inferred from solar wind data and proposed by theories for the corona and solar wind. The coronal background particles are assumed to follow kappa ({kappa}) distributions. The predicted f{sub p} emission of type III bursts is sensitive via the {kappa} index to the presence of suprathermal background particles, where f{sub p} is the local plasma frequency. The simulations show that (1) the speeds v{sub b} of type III beams are much larger (e.g., v{sub b} Almost-Equal-To 0.58c for {kappa} = 5) and so type III bursts drift much faster for low {kappa} ({<=}5) background plasmas than for Maxwellian backgrounds (producing v{sub b} < 0.3c), and (2) f{sub p} emission generated in a {kappa}-distributed background corona has a larger total bandwidth than in a Maxwellian background, for similar onset frequencies. Type III beams are thus more persistent, i.e., extending over larger distances, in {kappa}-distributed corona. Consequently, observations of fast-drifting coronal type III bursts and associated fast electron beams suggest that the ambient electrons in the corona are {kappa}-distributed, at least when such bursts are observed. These results support, from the new viewpoint of nonthermal radio emission, the occasional presence of suprathermal background electrons in the corona and the associated mechanisms (e.g., 'velocity filtration') for coronal heating and solar wind acceleration. The new results also help resolve longstanding issues regarding the speeds and persistence of type III beams, and the production of remotely observable levels of f{sub p} emission despite severe losses during propagation.

  2. Investigation of Containment Flooding Strategy for Mark-III Nuclear Power Plant with MAAP4

    SciTech Connect

    Su Weinian; Wang, S.-J.; Chiang, S.-C

    2005-06-15

    Containment flooding is an important strategy for severe accident management of a conventional boiling water reactor (BWR) system. The purpose of this work is to investigate the containment flooding strategy of the Mark-III system after a reactor pressure vessel (RPV) breach. The Kuosheng Power Plant is a typical BWR-6 nuclear power plant (NPP) with Mark-III containment. The Severe Accident Management Guideline (SAMG) of the Kuosheng NPP has been developed based on the BWR Owners Group (BWROG) Emergency Procedure and Severe Accident Guidelines, Rev. 2. Therefore, the Kuosheng NPP is selected as the plant for study, and the MAAP4 code is chosen as the tool for analysis. A postulated specific station blackout sequence for the Kuosheng NPP is cited as a reference case for this analysis. Because of the design features of Mark-III containment, the debris in the reactor cavity may not be submerged after an RPV breach when one follows the containment flooding strategy as suggested in the BWROG generic guideline, and the containment integrity could be challenged eventually. A more specific containment flooding strategy with drywell venting after an RPV breach is investigated, and a more stable plant condition is achieved with this strategy. Accordingly, the containment flooding strategy after an RPV breach will be modified for the Kuosheng SAMG, and these results are applicable to typical Mark-III plants with drywell vent path.

  3. Type III Protein Secretion Systems in Bacterial Pathogens of Animals and Plants

    PubMed Central

    Hueck, Christoph J.

    1998-01-01

    Various gram-negative animal and plant pathogens use a novel, sec-independent protein secretion system as a basic virulence mechanism. It is becoming increasingly clear that these so-called type III secretion systems inject (translocate) proteins into the cytosol of eukaryotic cells, where the translocated proteins facilitate bacterial pathogenesis by specifically interfering with host cell signal transduction and other cellular processes. Accordingly, some type III secretion systems are activated by bacterial contact with host cell surfaces. Individual type III secretion systems direct the secretion and translocation of a variety of unrelated proteins, which account for species-specific pathogenesis phenotypes. In contrast to the secreted virulence factors, most of the 15 to 20 membrane-associated proteins which constitute the type III secretion apparatus are conserved among different pathogens. Most of the inner membrane components of the type III secretion apparatus show additional homologies to flagellar biosynthetic proteins, while a conserved outer membrane factor is similar to secretins from type II and other secretion pathways. Structurally conserved chaperones which specifically bind to individual secreted proteins play an important role in type III protein secretion, apparently by preventing premature interactions of the secreted factors with other proteins. The genes encoding type III secretion systems are clustered, and various pieces of evidence suggest that these systems have been acquired by horizontal genetic transfer during evolution. Expression of type III secretion systems is coordinately regulated in response to host environmental stimuli by networks of transcription factors. This review comprises a comparison of the structure, function, regulation, and impact on host cells of the type III secretion systems in the animal pathogens Yersinia spp., Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhimurium, enteropathogenic Escherichia coli

  4. Insight into mechanism of lanthanum (III) induced damage to plant photosynthesis.

    PubMed

    Hu, Huiqing; Wang, Lihong; Li, Yueli; Sun, Jingwen; Zhou, Qing; Huang, Xiaohua

    2016-05-01

    A great deal of literature is available regarding the environmental and ecological effects of rare earth element pollution on plants. These studies have shown that excess lanthanum (La) (III) in the environment can inhibit plant growth and even cause plant death. Moreover, inhibition of plant photosynthesis is known to be one of the physiological bases of these damages. However, the mechanism responsible for these effects is still unclear. In this study, the mechanism of La(III)-induced damage to plant photosynthesis was clarified from the viewpoint of the chloroplast ultrastructure, the contents of chloroplast mineral elements and chlorophyll, the transcription of chloroplast ATPase subunits and chloroplast Mg(2+)-ATPase activity, in which rice was selected as a study object. Following treatment with low level of La(III), the chloroplast ultrastructure of rice was not changed, and the contents of chloroplast mineral elements (Mg, P, K, Ca, Mn, Fe, Ni, Cu, and Zn) increased, but the chlorophyll content did not change significantly. Moreover, the transcription of chloroplast ATPase subunits, chloroplast Mg(2+)-ATPase activity, the net photosynthetic rate and growth indices increased. Following treatment with high levels of La(III), the chloroplast ultrastructure was damaged, chloroplast mineral elements (except Cu and Zn) and chlorophyll contents decreased, and the transcription of chloroplast ATPase subunits, chloroplast Mg(2+)-ATPase activity, the net photosynthetic rate and growth indices decreased. Based on these results, a possible mechanism of La(III)-induced damage to plant photosynthesis was proposed to provide a reference for scientific evaluation of the potential ecological risk of rare earth elements in the environment.

  5. The distribution of lamprey GnRH-III in brains of adult sea lampreys (Petromyzon marinus).

    PubMed

    Nozaki, M; Ominato, K; Gorbman, A; Sower, S A

    2000-04-01

    In the sea lamprey, Petromyzon marinus, two forms of GnRH, lamprey GnRH-I and -III, have been demonstrated to be neurohormones regulating the pituitary-gonadal axis. The objective of the present study was to determine the distribution of lamprey GnRH-III in the brains of adult sea lampreys and to compare it to the distribution of lamprey GnRH-I. For this purpose, two kinds of immunostaining were employed: one was a single immunostaining by one of two GnRH antibodies using two successive sections; the other was double immunostaining of a single section. A dense accumulation of neuronal cells immunoreactive (ir) to antisera against either lamprey GnRH-I or -III was found in the arc-shaped preoptico-anterior hypothalamic area. Additional smaller numbers of irGnRH cells were found in the periventricular zone of the posterior hypothalamus. In the above-mentioned locations, the distribution of both irGnRH-I and -III cells was intermixed and very similar, but the cells exhibiting GnRH-III immunoreactivity were distinctly different from those exhibiting GnRH-I immunoreactivity. The relative numbers of irGnRH-III cells were larger than those of irGnRH-I cells in the preoptico-anterior hypothalamic area, and more than 90% of GnRH cells in the posterior hypothalamus were irGnRH-III cells. Both irGnRH-I and -III cells projected their fibers primarily into the neurohypophysis. The relative densities of the accumulated irGnRH-III fibers were similar to those of irGnRH-I fibers in the anterior neurohypophysis but higher than those of irGnRH-I fibers in the posterior neurohypophysis. The present study provides further immunocytochemical data to the already compelling physiological evidence that indicates that both lamprey GnRH-I and -III act through the hypothalamic-pituitary-gonadal axis to modulate reproductive processes in the sea lamprey.

  6. Working toward integrated models of alpine plant distribution

    PubMed Central

    Carlson, Bradley Z.; Randin, Christophe F.; Boulangeat, Isabelle; Lavergne, Sébastien; Thuiller, Wilfried; Choler, Philippe

    2014-01-01

    Species distribution models (SDMs) have been frequently employed to forecast the response of alpine plants to global changes. Efforts to model alpine plant distribution have thus far been primarily based on a correlative approach, in which ecological processes are implicitly addressed through a statistical relationship between observed species occurrences and environmental predictors. Recent evidence, however, highlights the shortcomings of correlative SDMs, especially in alpine landscapes where plant species tend to be decoupled from atmospheric conditions in micro-topographic habitats and are particularly exposed to geomorphic disturbances. While alpine plants respond to the same limiting factors as plants found at lower elevations, alpine environments impose a particular set of scale-dependent and hierarchical drivers that shape the realized niche of species and that require explicit consideration in a modelling context. Several recent studies in the European Alps have successfully integrated both correlative and process-based elements into distribution models of alpine plants, but for the time being a single integrative modelling framework that includes all key drivers remains elusive. As a first step in working toward a comprehensive integrated model applicable to alpine plant communities, we propose a conceptual framework that structures the primary mechanisms affecting alpine plant distributions. We group processes into four categories, including multi-scalar abiotic drivers, gradient dependent species interactions, dispersal and spatial–temporal plant responses to disturbance. Finally, we propose a methodological framework aimed at developing an integrated model to better predict alpine plant distribution. PMID:24790594

  7. The Arabidopsis Endosomal Sorting Complex Required for Transport III Regulates Internal Vesicle Formation of the Prevacuolar Compartment and Is Required for Plant Development1[C][W][OPEN

    PubMed Central

    Cai, Yi; Zhuang, Xiaohong; Gao, Caiji; Wang, Xiangfeng; Jiang, Liwen

    2014-01-01

    We have established an efficient transient expression system with several vacuolar reporters to study the roles of endosomal sorting complex required for transport (ESCRT)-III subunits in regulating the formation of intraluminal vesicles of prevacuolar compartments (PVCs)/multivesicular bodies (MVBs) in plant cells. By measuring the distributions of reporters on/within the membrane of PVC/MVB or tonoplast, we have identified dominant negative mutants of ESCRT-III subunits that affect membrane protein degradation from both secretory and endocytic pathways. In addition, induced expression of these mutants resulted in reduction in luminal vesicles of PVC/MVB, along with increased detection of membrane-attaching vesicles inside the PVC/MVB. Transgenic Arabidopsis (Arabidopsis thaliana) plants with induced expression of ESCRT-III dominant negative mutants also displayed severe cotyledon developmental defects with reduced cell size, loss of the central vacuole, and abnormal chloroplast development in mesophyll cells, pointing out an essential role of the ESCRT-III complex in postembryonic development in plants. Finally, membrane dissociation of ESCRT-III components is important for their biological functions and is regulated by direct interaction among Vacuolar Protein Sorting-Associated Protein20-1 (VPS20.1), Sucrose Nonfermenting7-1, VPS2.1, and the adenosine triphosphatase VPS4/SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1. PMID:24812106

  8. Of guards, decoys, baits and traps: pathogen perception in plants by type III effector sensors.

    PubMed

    Khan, Madiha; Subramaniam, Rajagopal; Desveaux, Darrell

    2016-02-01

    Effector-triggered immunity (ETI) is conferred by dominant plant resistance (R) genes, which encode predominantly nucleotide-binding and leucine-rich repeat domain proteins (NLRs), against cognate microbial avirulence (Avr) genes, which include bacterial type III secreted effectors (T3Es). The 'guard model' describes the mechanism of T3E perception by plants, whereby NLRs monitor host proteins ('sensors') for T3E-induced perturbations. This model has provided a molecular framework to understand T3E perception and has rationalized how plants can use a limited number of NLRs (∼160 in Arabidopsis) to contend with a potentially limitless number of evolving effectors. In this review we provide a characteristic overview of plant T3E sensors and discuss how these sensors convey the presence of T3Es to NLR proteins to activate ETI.

  9. Coal quality trends and distribution of Title III trace elements in Eastern Kentucky coals

    SciTech Connect

    Eble, C.F.; Hower, J.C.

    1995-12-31

    The quality characteristics of eastern Kentucky coal beds vary both spatially and stratigraphically. Average total sulfur contents are lowest, and calorific values highest, in the Big Sandy and Upper Cumberland Reserve Districts. Average coal thickness is greatest in these two districts as well. Conversely, the thinnest coal with the highest total sulfur content, and lowest calorific value, on average, occurs in the Princess and Southwest Reserve Districts. Several Title III trace elements, notably arsenic, cadmium, lead, mercury, and nickel, mirror this distribution (lower average concentrations in the Big Sandy and Upper Cumberland Districts, higher average concentrations in the Princess and Southwest Districts), probably because these elements are primarily associated with sulfide minerals in coal. Ash yields and total sulfur contents are observed to increase in a stratigraphically older to younger direction. Several Title III elements, notably cadmium, chromium, lead, and selenium follow this trend, with average concentrations being higher in younger coals. Average chlorine concentration shows a reciprocal distribution, being more abundant in older coals. Some elements, such as arsenic, manganese, mercury, cobalt, and, to a lesser extent, phosphorus show concentration spikes in coal beds directly above, or below, major marine zones. With a few exceptions, average Title III trace element concentrations for eastern Kentucky coals are comparable with element distributions in other Appalachian coal-producing states.

  10. The Distribution of Scaled Scores and Possible Floor Effects on the WISC-III and WAIS-III

    ERIC Educational Resources Information Center

    Whitaker, Simon; Wood, Christopher

    2008-01-01

    Objective: It has been suggested that, as the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) give a scaled score of one even if a client scores a raw score of zero, these assessments may have a hidden floor effect at low IQ levels. The study looked for…

  11. Accumulation and distribution of 137Cs in tropical plants

    NASA Astrophysics Data System (ADS)

    Anjos, R. M.; Carvalho, C.; Mosquera, B.; Veiga, R.; Sanches, N.; Bastos, J.; Macario, K.

    2007-02-01

    The accumulation and distribution of 40K and 137Cs in several tropical plant species were studied through measurements of gamma-ray spectra, focusing on establishing the suitability of using radiocesium to trace the plant uptake of nutrients such as potassium.

  12. Accumulation and distribution of 137Cs in tropical plants

    SciTech Connect

    Anjos, R. M.; Carvalho, C.; Mosquera, B.; Veiga, R.; Sanches, N.; Bastos, J.; Macario, K.

    2007-02-12

    The accumulation and distribution of 40K and 137Cs in several tropical plant species were studied through measurements of gamma-ray spectra, focusing on establishing the suitability of using radiocesium to trace the plant uptake of nutrients such as potassium.

  13. Optimality of nitrogen distribution among leaves in plant canopies.

    PubMed

    Hikosaka, Kouki

    2016-05-01

    The vertical gradient of the leaf nitrogen content in a plant canopy is one of the determinants of vegetation productivity. The ecological significance of the nitrogen distribution in plant canopies has been discussed in relation to its optimality; nitrogen distribution in actual plant canopies is close to but always less steep than the optimal distribution that maximizes canopy photosynthesis. In this paper, I review the optimality of nitrogen distribution within canopies focusing on recent advancements. Although the optimal nitrogen distribution has been believed to be proportional to the light gradient in the canopy, this rule holds only when diffuse light is considered; the optimal distribution is steeper when the direct light is considered. A recent meta-analysis has shown that the nitrogen gradient is similar between herbaceous and tree canopies when it is expressed as the function of the light gradient. Various hypotheses have been proposed to explain why nitrogen distribution is suboptimal. However, hypotheses explain patterns observed in some specific stands but not in others; there seems to be no general hypothesis that can explain the nitrogen distributions under different conditions. Therefore, how the nitrogen distribution in canopies is determined remains open for future studies; its understanding should contribute to the correct prediction and improvement of plant productivity under changing environments. PMID:27059755

  14. Accumulation and distribution of iron, cadmium, lead and nickel in cucumber plants grown in hydroponics containing two different chelated iron supplies.

    PubMed

    Csog, Árpád; Mihucz, Victor G; Tatár, Eniko; Fodor, Ferenc; Virág, István; Majdik, Cornelia; Záray, Gyula

    2011-07-01

    Cucumber plants grown in hydroponics containing 10 μM Cd(II), Ni(II) and Pb(II), and iron supplied as Fe(III) EDTA or Fe(III) citrate in identical concentrations, were investigated by total-reflection X-ray fluorescence spectrometry with special emphasis on the determination of iron accumulation and distribution within the different plant compartments (root, stem, cotyledon and leaves). The extent of Cd, Ni and Pb accumulation and distribution were also determined. Generally, iron and heavy-metal contaminant accumulation was higher when Fe(III) citrate was used. The accumulation of nickel and lead was higher by about 20% and 100%, respectively, if the iron supply was Fe(III) citrate. The accumulation of Cd was similar. In the case of Fe(III) citrate, the total amounts of Fe taken up were similar in the control and heavy-metal-treated plants (27-31 μmol/plant). Further, the amounts of iron transported from the root towards the shoot of the control, lead- and nickel-contaminated plants were independent of the iron(III) form. Although Fe mobility could be characterized as being low, its distribution within the shoot was not significantly affected by the heavy metals investigated.

  15. The signature of randomness in riparian plant root distributions

    NASA Astrophysics Data System (ADS)

    Tron, Stefania; Perona, Paolo; Gorla, Lorenzo; Schwarz, Massimiliano; Laio, Francesco; Ridolfi, Luca

    2015-09-01

    Known as "the hidden half", plant roots are fundamental contributors to the riparian ecosystem functioning. Roots show an extraordinary architectural complexity that recalls their remarkable ability to adapt to environmental heterogeneity, resources availability, and climate. In fluvial environments, phreatophytes and hydrophytes cope with flow and sediment processes, and hydrotropism and aerotropism are the main drivers for root growth. In this work, we show how the vertical root density distribution in riparian plants is the result of how plants respond to the random fluctuations of river flows. A root data set from field and controlled outdoor experiments is used in combination with a physically based analytical model to demonstrate that the root vertical density distribution can be ascribed to the interplay of randomness and determinism in a simple mathematical form. The shape of the distribution reflects the profitability of plant roots to grow in different soil layers depending on the soil moisture availability. For the first time, this model helps understanding in an analytical manner the adaptation strategy of plant roots to different scenarios, paving the way for the comprehension of the effects of future changes in climate and environmental conditions.

  16. Distribution of chromium species in a Cr-polluted soil: presence of Cr(III) in glomalin related protein fraction.

    PubMed

    Gil-Cardeza, María L; Ferri, Alejandro; Cornejo, Pablo; Gomez, Elena

    2014-09-15

    The accumulation of Cr in soil could be highly toxic to human health; therefore Cr soil distribution was studied in rhizosphere soils from Ricinus communis and Conium maculatum and bare soil (BS) from an industrial and urban area in Argentina. Total Cr, Cr(VI) and Cr(III) concentrations were determined in 3 soil fractions: total, extractable and associated to total-glomalin-related protein (T-GRSP). BS had the highest total Cr and total Cr(VI) concentrations. Total Cr(VI) concentration from both rhizosphere soils did not differ from the allowed value for residential area in Argentina (8 μg Cr(VI) g(-1) soil), while total Cr(VI) in BS was 1.8 times higher. Total Cr concentration in all the soils was higher than the allowed value (250 μg Cr g(-1) soil). Extractable and associated to T-GRSP Cr(VI) concentrations were below the detection limit. Cr(III) bound to T-GRSP was the highest in the BS. These findings are in agreement with a long term effect of glomalin in sequestrating Cr. In both plant species, total Cr was higher in root than in shoot and both species presented arbuscular mycorrhizal fungi (AMF). As far as we know, this is the first study that reports the presence of Cr in T-GRSP fraction of soil organic matter. These findings suggest that Cr mycorrhizostabilization could be a predominant mechanism used by R. communis and C. maculatum to diminish Cr soil concentration. Nevertheless, further research is needed to clarify the contribution of native AMF isolated from R. communis and C. maculatum rhizosphere to the Cr phytoremediation process.

  17. Distributions of exotic plants in eastern Asia and North America

    USGS Publications Warehouse

    Guo, Q.; Qian, H.; Ricklefs, R.E.; Xi, W.

    2006-01-01

    Although some plant traits have been linked to invasion success, the possible effects of regional factors, such as diversity, habitat suitability, and human activity are not well understood. Each of these mechanisms predicts a different pattern of distribution at the regional scale. Thus, where climate and soils are similar, predictions based on regional hypotheses for invasion success can be tested by comparisons of distributions in the source and receiving regions. Here, we analyse the native and alien geographic ranges of all 1567 plant species that have been introduced between eastern Asia and North America or have been introduced to both regions from elsewhere. The results reveal correlations between the spread of exotics and both the native species richness and transportation networks of recipient regions. This suggests that both species interactions and human-aided dispersal influence exotic distributions, although further work on the relative importance of these processes is needed. ?? 2006 Blackwell Publishing Ltd/CNRS.

  18. Factors driving distribution limits in an annual plant community.

    PubMed

    Emery, Nancy C; Stanton, Maureen L; Rice, Kevin J

    2009-01-01

    Studies examining plant distribution patterns across environmental gradients have generally focused on perennial-dominated systems, and we know relatively little about the processes structuring annual communities. Here, the ecological factors determining local distribution patterns of five dominant annual species distributed across micro-topographic gradients in ephemeral California wetlands are examined. Over two growing seasons in three vernal pools, patterns of inundation and above-ground biomass were characterized across the microtopographic gradient, population boundaries for five dominant species were documented and a reciprocal transplant experiment and neighbor removal treatment were conducted to test the relative effects of within-pool elevation, competition and seed dispersal on plant performance. Despite large differences in inundation time between growing seasons, above-ground biomass and the elevation of population boundaries remained consistent. The predicted 'optimal' depth for each species shifted between years, but competition and recruitment limitation restricted species' abilities to track these conditions. The distributions of the focal taxa are primarily driven by differential responses to environmental conditions associated with different microtopographic positions along pool inundation gradients, and are reinforced by competition and dispersal constraints. The relative importance of competition, other environmental factors and dispersal patterns appear to contrast with results obtained in systems dominated by perennial plants. PMID:19154319

  19. Type III Secretion System Genes of Dickeya dadantii 3937 Are Induced by Plant Phenolic Acids

    PubMed Central

    Yang, Shihui; Peng, Quan; San Francisco, Michael; Wang, Yongjun; Zeng, Quan; Yang, Ching-Hong

    2008-01-01

    Background Dickeya dadantii is a broad-host range phytopathogen. D. dadantii 3937 (Ech3937) possesses a type III secretion system (T3SS), a major virulence factor secretion system in many Gram-negative pathogens of plants and animals. In Ech3937, the T3SS is regulated by two major regulatory pathways, HrpX/HrpY-HrpS-HrpL and GacS/GacA-rsmB-RsmA pathways. Although the plant apoplast environment, low pH, low temperature, and absence of complex nitrogen sources in media have been associated with the induction of T3SS genes of phytobacteria, no specific inducer has yet been identified. Methodology/Principal Findings In this work, we identified two novel plant phenolic compounds, o-coumaric acid (OCA) and t-cinnamic acid (TCA), that induced the expression of T3SS genes dspE (a T3SS effector), hrpA (a structural protein of the T3SS pilus), and hrpN (a T3SS harpin) in vitro. Assays by qRT-PCR showed higher amounts of mRNA of hrpL (a T3SS alternative sigma factor) and rsmB (an untranslated regulatory RNA), but not hrpS (a σ54-enhancer binding protein) of Ech3937 when these two plant compounds were supplemented into minimal medium (MM). However, promoter activity assays using flow cytometry showed similar promoter activities of hrpN in rsmB mutant Ech148 grown in MM and MM supplemented with these phenolic compounds. Compared with MM alone, only slightly higher promoter activities of hrpL were observed in bacterial cells grown in MM supplemented with OCA/TCA. Conclusion/Significance The induction of T3SS expression by OCA and TCA is moderated through the rsmB-RsmA pathway. This is the first report of plant phenolic compounds that induce the expression T3SS genes of plant pathogenic bacteria. PMID:18698421

  20. Constitutive expression of the xylanase inhibitor TAXI-III delays Fusarium head blight symptoms in durum wheat transgenic plants.

    PubMed

    Moscetti, Ilaria; Tundo, Silvio; Janni, Michela; Sella, Luca; Gazzetti, Katia; Tauzin, Alexandra; Giardina, Thierry; Masci, Stefania; Favaron, Francesco; D'Ovidio, Renato

    2013-12-01

    Cereals contain xylanase inhibitor (XI) proteins which inhibit microbial xylanases and are considered part of the defense mechanisms to counteract microbial pathogens. Nevertheless, in planta evidence for this role has not been reported yet. Therefore, we produced a number of transgenic plants constitutively overexpressing TAXI-III, a member of the TAXI type XI that is induced by pathogen infection. Results showed that TAXI-III endows the transgenic wheat with new inhibition capacities. We also showed that TAXI-III is correctly secreted into the apoplast and possesses the expected inhibition parameters against microbial xylanases. The new inhibition properties of the transgenic plants correlate with a significant delay of Fusarium head blight disease symptoms caused by Fusarium graminearum but do not significantly influence leaf spot symptoms caused by Bipolaris sorokiniana. We showed that this contrasting result can be due to the different capacity of TAXI-III to inhibit the xylanase activity of these two fungal pathogens. These results provide, for the first time, clear evidence in planta that XI are involved in plant defense against fungal pathogens and show the potential to manipulate TAXI-III accumulation to improve wheat resistance against F. graminearum.

  1. User's guide for the BNW-III optimization code for modular dry/wet-cooled power plants

    SciTech Connect

    Braun, D.J.; Faletti, D.W.

    1984-09-01

    This user's guide describes BNW-III, a computer code developed by the Pacific Northwest Laboratory (PNL) as part of the Dry Cooling Enhancement Program sponsored by the US Department of Energy (DOE). The BNW-III code models a modular dry/wet cooling system for a nuclear or fossil fuel power plant. The purpose of this guide is to give the code user a brief description of what the BNW-III code is and how to use it. It describes the cooling system being modeled and the various models used. A detailed description of code input and code output is also included. The BNW-III code was developed to analyze a specific cooling system layout. However, there is a large degree of freedom in the type of cooling modules that can be selected and in the performance of those modules. The costs of the modules are input to the code, giving the user a great deal of flexibility.

  2. 76 FR 6812 - Proposed Shiloh III Wind Plant Project, Solano County, CA; Proposed Habitat Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ... Fish and Wildlife Service Proposed Shiloh III Wind Plant Project, Solano County, CA; Proposed Habitat... Area). The Plan Area is adjacent to existing energy-producing facilities, most notably wind turbine.../California Independent System Operator power grid. Up to 59 wind turbines would be built in the Plan...

  3. Draft Genome Sequence of 16SrIII-J Phytoplasma, a Plant Pathogenic Bacterium with a Broad Spectrum of Hosts

    PubMed Central

    Zamorano, Alan

    2016-01-01

    Phytoplasmas are bacterial plant pathogens that can affect different vegetal hosts. In South America, a phytoplasma belonging to ribosomal subgroup 16SrIII-J has been reported in many crops. Here we report its genomic draft sequence, showing a total length of 687,253 bp and a G+C content of 27.72%. PMID:27365349

  4. Draft Genome Sequence of 16SrIII-J Phytoplasma, a Plant Pathogenic Bacterium with a Broad Spectrum of Hosts.

    PubMed

    Zamorano, Alan; Fiore, Nicola

    2016-06-30

    Phytoplasmas are bacterial plant pathogens that can affect different vegetal hosts. In South America, a phytoplasma belonging to ribosomal subgroup 16SrIII-J has been reported in many crops. Here we report its genomic draft sequence, showing a total length of 687,253 bp and a G+C content of 27.72%.

  5. Suppression of RNAi by dsRNA-Degrading RNaseIII Enzymes of Viruses in Animals and Plants

    PubMed Central

    Matilainen, Olli; Kallijärvi, Jukka; Cuellar, Wilmer J.; Lu, Rui; Saarma, Mart; Holmberg, Carina I.; Jäntti, Jussi; Valkonen, Jari P. T.

    2015-01-01

    Certain RNA and DNA viruses that infect plants, insects, fish or poikilothermic animals encode Class 1 RNaseIII endoribonuclease-like proteins. dsRNA-specific endoribonuclease activity of the RNaseIII of rock bream iridovirus infecting fish and Sweet potato chlorotic stunt crinivirus (SPCSV) infecting plants has been shown. Suppression of the host antiviral RNA interference (RNAi) pathway has been documented with the RNaseIII of SPCSV and Heliothis virescens ascovirus infecting insects. Suppression of RNAi by the viral RNaseIIIs in non-host organisms of different kingdoms is not known. Here we expressed PPR3, the RNaseIII of Pike-perch iridovirus, in the non-hosts Nicotiana benthamiana (plant) and Caenorhabditis elegans (nematode) and found that it cleaves double-stranded small interfering RNA (ds-siRNA) molecules that are pivotal in the host RNA interference (RNAi) pathway and thereby suppresses RNAi in non-host tissues. In N. benthamiana, PPR3 enhanced accumulation of Tobacco rattle tobravirus RNA1 replicon lacking the 16K RNAi suppressor. Furthermore, PPR3 suppressed single-stranded RNA (ssRNA)—mediated RNAi and rescued replication of Flock House virus RNA1 replicon lacking the B2 RNAi suppressor in C. elegans. Suppression of RNAi was debilitated with the catalytically compromised mutant PPR3-Ala. However, the RNaseIII (CSR3) produced by SPCSV, which cleaves ds-siRNA and counteracts antiviral RNAi in plants, failed to suppress ssRNA-mediated RNAi in C. elegans. In leaves of N. benthamiana, PPR3 suppressed RNAi induced by ssRNA and dsRNA and reversed silencing; CSR3, however, suppressed only RNAi induced by ssRNA and was unable to reverse silencing. Neither PPR3 nor CSR3 suppressed antisense-mediated RNAi in Drosophila melanogaster. These results show that the RNaseIII enzymes of RNA and DNA viruses suppress RNAi, which requires catalytic activities of RNaseIII. In contrast to other viral silencing suppression proteins, the RNaseIII enzymes are homologous in

  6. Global distribution of plant-extractable water capacity of soil

    USGS Publications Warehouse

    Dunne, K.A.; Willmott, C.J.

    1996-01-01

    Plant-extractable water capacity of soil is the amount of water that can be extracted from the soil to fulfill evapotranspiration demands. It is often assumed to be spatially invariant in large-scale computations of the soil-water balance. Empirical evidence, however, suggests that this assumption is incorrect. In this paper, we estimate the global distribution of the plant-extractable water capacity of soil. A representative soil profile, characterized by horizon (layer) particle size data and thickness, was created for each soil unit mapped by FAO (Food and Agriculture Organization of the United Nations)/Unesco. Soil organic matter was estimated empirically from climate data. Plant rooting depths and ground coverages were obtained from a vegetation characteristic data set. At each 0.5?? ?? 0.5?? grid cell where vegetation is present, unit available water capacity (cm water per cm soil) was estimated from the sand, clay, and organic content of each profile horizon, and integrated over horizon thickness. Summation of the integrated values over the lesser of profile depth and root depth produced an estimate of the plant-extractable water capacity of soil. The global average of the estimated plant-extractable water capacities of soil is 8??6 cm (Greenland, Antarctica and bare soil areas excluded). Estimates are less than 5, 10 and 15 cm - over approximately 30, 60, and 89 per cent of the area, respectively. Estimates reflect the combined effects of soil texture, soil organic content, and plant root depth or profile depth. The most influential and uncertain parameter is the depth over which the plant-extractable water capacity of soil is computed, which is usually limited by root depth. Soil texture exerts a lesser, but still substantial, influence. Organic content, except where concentrations are very high, has relatively little effect.

  7. Global Distribution of Plant-Extractable Water Capacity of Soil

    NASA Astrophysics Data System (ADS)

    Dunne, K. A.; Willmott, Cort J.

    1996-08-01

    Plant-extractable water capacity of soil is the amount of water that can be extracted from the soil to fulfill evapotranspiration demands. It is often assumed to be spatially invariant in large-scale computations of the soil-water balance. Empirical evidence, however, suggests that this assumption is incorrect. In this paper, we estimate the global distribution of the plant-extractable water capacity of soil.A representative soil profile, characterized by horizon (layer) particle size data and thickness, was created for each soil unit mapped by FAO (Food and Agriculture Organization of the United Nations)/Unesco. Soil organic matter was estimated empirically from climate data. Plant rooting depths and ground coverages were obtained from a vegetation characteristic data set. At each 0.5°×0.5° grid cell where vegetation is present, unit available water capacity (cm water per cm soil) was estimated from the sand, clay, and organic content of each profile horizon, and integrated over horizon thickness. Summation of the integrated values over the lesser of profile depth and root depth produced an estimate of the plant-extractable water capacity of soil.The global average of the estimated plant-extractable water capacities of soil is 86cm (Greenland, Antarctica and bare soil areas excluded). Estimates are less than 5, 10 and 15 cm - over approximately 30, 60, and 89 per cent of the area, respectively. Estimates reflect the combined effects of soil texture, soil organic content, and plant root depth or profile depth. The most influential and uncertain parameter is the depth over which the plant- extractable water capacity of soil is computed, which is usually limited by root depth. Soil texture exerts a lesser, but still substantial, influence. Organic content, except where concentrations are very high, has relatively little effect.

  8. Distribution of polycyclic aromatic hydrocarbons in coke plant wastewater.

    PubMed

    Burmistrz, Piotr; Burmistrz, Michał

    2013-01-01

    The subject of examinations presented in this paper is the distribution of polycyclic aromatic hydrocarbons (PAHs) between solid and liquid phases in samples of raw wastewater and wastewater after treatment. The content of 16 PAHs according to the US EPA was determined in the samples of coke plant wastewater from the Zdzieszowice Coke Plant, Poland. The samples contained raw wastewater, wastewater after physico-chemical treatment as well as after biological treatment. The ΣPHA16 content varied between 255.050 μg L(-1) and 311.907 μg L(-1) in raw wastewater and between 0.940 and 4.465 μg L(-1) in wastewater after full treatment. Investigation of the distribution of PAHs showed that 71-84% of these compounds is adsorbed on the surface of suspended solids and 16-29% is dissolved in water. Distribution of individual PAHs and ΣPHA16 between solid phase and liquid phase was described with the use of statistically significant, linear equations. The calculated values of the partitioning coefficient Kp changed from 0.99 to 7.90 for naphthalene in samples containing mineral-organic suspension and acenaphthylene in samples with biological activated sludge, respectively.

  9. Using geomorphology to map plant community distribution in complex polygonal tundra landscapes

    NASA Astrophysics Data System (ADS)

    Sloan, V. L.; Gangodagamage, C.; Iversen, C. M.; Norby, R. J.; Wullschleger, S. D.

    2014-12-01

    Climate change over the next century is expected to substantially alter Arctic ecosystem structure and function, resulting in important feedbacks to global climate. Representing Arctic landscapes in the carbon cycle and climate models, however, is challenging because vegetation and soils vary over small spatial scales. Robust approaches are needed for identifying distinct plant communities for fine-scale model parameterizations, and for mapping the distribution of these communities to enable scaling from plot to grid-cell. Here, we demonstrate how a novel technique using LiDAR-derived metrics to delineate micro-topographic features can also be applied to mapping plant community distribution in a polygonal tundra landscape on the Barrow Environmental Observatory (BEO), Alaska. We recorded species composition in 48, 1 x 1 m plots located across contrasting ice-wedge polygon types on the BEO in July 2012. One-way cluster analysis and non-metric multidimensional scaling identified four major plant communities, namely i) tall Carex (sedge) dominated communities, ii) mixed tall graminoid-forb-moss communities, iii) dry graminoid-lichen communities and iv) low-stature, lichen dominated-communities. These communities were strongly linked to micro-topography, corresponding with i) low centers ii) troughs, iii) rims and transitional polygon centers, and iv) high centers. We therefore combined plant community type with geomorphological analyses using high-resolution LiDAR-derived metrics (e.g. slope, curvature, flowpath distances) to delineate micro-topographic features to produce a vegetation map. The map was verified using 24 field survey transects in which plant community boundaries were mapped using DGPS. The approach performed well, with only a small (5%) over-estimate of the extent of trough communities and a corresponding under-estimate of rim and transitional center communities. Overall, these analyses provide a framework which can be used for parameterizing fine

  10. Phylogeny and Expression Analyses Reveal Important Roles for Plant PKS III Family during the Conquest of Land by Plants and Angiosperm Diversification.

    PubMed

    Xie, Lulu; Liu, Pingli; Zhu, Zhixin; Zhang, Shifan; Zhang, Shujiang; Li, Fei; Zhang, Hui; Li, Guoliang; Wei, Yunxiao; Sun, Rifei

    2016-01-01

    Polyketide synthases (PKSs) utilize the products of primary metabolism to synthesize a wide array of secondary metabolites in both prokaryotic and eukaryotic organisms. PKSs can be grouped into three distinct classes, types I, II, and III, based on enzyme structure, substrate specificity, and catalytic mechanisms. The type III PKS enzymes function as homodimers, and are the only class of PKS that do not require acyl carrier protein. Plant type III PKS enzymes, also known as chalcone synthase (CHS)-like enzymes, are of particular interest due to their functional diversity. In this study, we mined type III PKS gene sequences from the genomes of six aquatic algae and 25 land plants (1 bryophyte, 1 lycophyte, 2 basal angiosperms, 16 core eudicots, and 5 monocots). PKS III sequences were found relatively conserved in all embryophytes, but not exist in algae. We also examined gene expression patterns by analyzing available transcriptome data, and identified potential cis-regulatory elements in upstream sequences. Phylogenetic trees of dicots angiosperms showed that plant type III PKS proteins fall into three clades. Clade A contains CHS/STS-type enzymes coding genes with diverse transcriptional expression patterns and enzymatic functions, while clade B is further divided into subclades b1 and b2, which consist of anther-specific CHS-like enzymes. Differentiation regions, such as amino acids 196-207 between clades A and B, and predicted positive selected sites within α-helixes in late appeared branches of clade A, account for the major diversification in substrate choice and catalytic reaction. The integrity and location of conserved cis-elements containing MYB and bHLH binding sites can affect transcription levels. Potential binding sites for transcription factors such as WRKY, SPL, or AP2/EREBP may contribute to tissue- or taxon-specific differences in gene expression. Our data shows that gene duplications and functional diversification of plant type III PKS enzymes

  11. Phylogeny and Expression Analyses Reveal Important Roles for Plant PKS III Family during the Conquest of Land by Plants and Angiosperm Diversification.

    PubMed

    Xie, Lulu; Liu, Pingli; Zhu, Zhixin; Zhang, Shifan; Zhang, Shujiang; Li, Fei; Zhang, Hui; Li, Guoliang; Wei, Yunxiao; Sun, Rifei

    2016-01-01

    Polyketide synthases (PKSs) utilize the products of primary metabolism to synthesize a wide array of secondary metabolites in both prokaryotic and eukaryotic organisms. PKSs can be grouped into three distinct classes, types I, II, and III, based on enzyme structure, substrate specificity, and catalytic mechanisms. The type III PKS enzymes function as homodimers, and are the only class of PKS that do not require acyl carrier protein. Plant type III PKS enzymes, also known as chalcone synthase (CHS)-like enzymes, are of particular interest due to their functional diversity. In this study, we mined type III PKS gene sequences from the genomes of six aquatic algae and 25 land plants (1 bryophyte, 1 lycophyte, 2 basal angiosperms, 16 core eudicots, and 5 monocots). PKS III sequences were found relatively conserved in all embryophytes, but not exist in algae. We also examined gene expression patterns by analyzing available transcriptome data, and identified potential cis-regulatory elements in upstream sequences. Phylogenetic trees of dicots angiosperms showed that plant type III PKS proteins fall into three clades. Clade A contains CHS/STS-type enzymes coding genes with diverse transcriptional expression patterns and enzymatic functions, while clade B is further divided into subclades b1 and b2, which consist of anther-specific CHS-like enzymes. Differentiation regions, such as amino acids 196-207 between clades A and B, and predicted positive selected sites within α-helixes in late appeared branches of clade A, account for the major diversification in substrate choice and catalytic reaction. The integrity and location of conserved cis-elements containing MYB and bHLH binding sites can affect transcription levels. Potential binding sites for transcription factors such as WRKY, SPL, or AP2/EREBP may contribute to tissue- or taxon-specific differences in gene expression. Our data shows that gene duplications and functional diversification of plant type III PKS enzymes

  12. Phylogeny and Expression Analyses Reveal Important Roles for Plant PKS III Family during the Conquest of Land by Plants and Angiosperm Diversification

    PubMed Central

    Xie, Lulu; Liu, Pingli; Zhu, Zhixin; Zhang, Shifan; Zhang, Shujiang; Li, Fei; Zhang, Hui; Li, Guoliang; Wei, Yunxiao; Sun, Rifei

    2016-01-01

    Polyketide synthases (PKSs) utilize the products of primary metabolism to synthesize a wide array of secondary metabolites in both prokaryotic and eukaryotic organisms. PKSs can be grouped into three distinct classes, types I, II, and III, based on enzyme structure, substrate specificity, and catalytic mechanisms. The type III PKS enzymes function as homodimers, and are the only class of PKS that do not require acyl carrier protein. Plant type III PKS enzymes, also known as chalcone synthase (CHS)-like enzymes, are of particular interest due to their functional diversity. In this study, we mined type III PKS gene sequences from the genomes of six aquatic algae and 25 land plants (1 bryophyte, 1 lycophyte, 2 basal angiosperms, 16 core eudicots, and 5 monocots). PKS III sequences were found relatively conserved in all embryophytes, but not exist in algae. We also examined gene expression patterns by analyzing available transcriptome data, and identified potential cis-regulatory elements in upstream sequences. Phylogenetic trees of dicots angiosperms showed that plant type III PKS proteins fall into three clades. Clade A contains CHS/STS-type enzymes coding genes with diverse transcriptional expression patterns and enzymatic functions, while clade B is further divided into subclades b1 and b2, which consist of anther-specific CHS-like enzymes. Differentiation regions, such as amino acids 196-207 between clades A and B, and predicted positive selected sites within α-helixes in late appeared branches of clade A, account for the major diversification in substrate choice and catalytic reaction. The integrity and location of conserved cis-elements containing MYB and bHLH binding sites can affect transcription levels. Potential binding sites for transcription factors such as WRKY, SPL, or AP2/EREBP may contribute to tissue- or taxon-specific differences in gene expression. Our data shows that gene duplications and functional diversification of plant type III PKS enzymes

  13. Phylogeny and Expression Analyses Reveal Important Roles for Plant PKS III Family during the Conquest of Land by Plants and Angiosperm Diversification

    PubMed Central

    Xie, Lulu; Liu, Pingli; Zhu, Zhixin; Zhang, Shifan; Zhang, Shujiang; Li, Fei; Zhang, Hui; Li, Guoliang; Wei, Yunxiao; Sun, Rifei

    2016-01-01

    Polyketide synthases (PKSs) utilize the products of primary metabolism to synthesize a wide array of secondary metabolites in both prokaryotic and eukaryotic organisms. PKSs can be grouped into three distinct classes, types I, II, and III, based on enzyme structure, substrate specificity, and catalytic mechanisms. The type III PKS enzymes function as homodimers, and are the only class of PKS that do not require acyl carrier protein. Plant type III PKS enzymes, also known as chalcone synthase (CHS)-like enzymes, are of particular interest due to their functional diversity. In this study, we mined type III PKS gene sequences from the genomes of six aquatic algae and 25 land plants (1 bryophyte, 1 lycophyte, 2 basal angiosperms, 16 core eudicots, and 5 monocots). PKS III sequences were found relatively conserved in all embryophytes, but not exist in algae. We also examined gene expression patterns by analyzing available transcriptome data, and identified potential cis-regulatory elements in upstream sequences. Phylogenetic trees of dicots angiosperms showed that plant type III PKS proteins fall into three clades. Clade A contains CHS/STS-type enzymes coding genes with diverse transcriptional expression patterns and enzymatic functions, while clade B is further divided into subclades b1 and b2, which consist of anther-specific CHS-like enzymes. Differentiation regions, such as amino acids 196-207 between clades A and B, and predicted positive selected sites within α-helixes in late appeared branches of clade A, account for the major diversification in substrate choice and catalytic reaction. The integrity and location of conserved cis-elements containing MYB and bHLH binding sites can affect transcription levels. Potential binding sites for transcription factors such as WRKY, SPL, or AP2/EREBP may contribute to tissue- or taxon-specific differences in gene expression. Our data shows that gene duplications and functional diversification of plant type III PKS enzymes

  14. Subcellular distribution and translocation of radionuclides in plants

    SciTech Connect

    Gouthu, S.; Weginwar, R.; Arie, Tsutomu; Ambe, Shizuko; Ozaki, Takuo; Enomoto, Shuichi; Ambe, Fumitoshi; Yamaguchi, Isamu

    1999-09-01

    The subcellular distribution of radionuclides in Glycine max Merr. (soybean) and Cucumis sativus L. (cucumber) and translocation of plant absorbed radionuclides with growth in soybean were studied. More than 60% of cellular incorporated Rb{sup {minus}83}, Sr{sup {minus}85}, Mn{sup {minus}54}, Nb{sup {minus}95}, and Se{sup {minus}75} remained in the supernatant fraction; 55% and 20% of Cr{sup {minus}51} was bound to soybean and cucumber cell wall fractions, respectively; 70% or more of Be{sup {minus}7}, Y{sup {minus}88}, and Fe{sup {minus}59} was fixed in the chloroplast fraction; and approx. 10% of Sc{sup {minus}46}, Fe{sup {minus}59}, V{sup {minus}48}, and As were fixed in the mitochondrial fraction. Translocation of nuclides within the soybean plant at different stages of growth has been determined. Vanadium, Y{sup {minus}88}, Be{sup {minus}7}, Se{sup {minus}75}, Nb{sup {minus}95}, Sc{sup {minus}46}, Cr{sup {minus}51}, and Zr{sup {minus}88} were predominantly accumulated in the root. Although the total percentage of plant uptake of Sc{sup {minus}46}, Zr{sup {minus}88}, Nb{sup {minus}95}, Sc{sup {minus}46}, and Cr{sup {minus}51} was high, because of low mobility and translocation to shoot, their accumulation in the fruit fraction was negligible. The translocation of mobile nuclides in plants was demonstrated clearly by Rb{sup {minus}83}, Zn{sup {minus}65}, and Fe{sup {minus}59}. Data on the nuclide fraction mobilized from vegetative parts into edible parts was used to assess the percentage of accumulated radionuclides in plants that may reach humans through beans.

  15. X-RAY AND CRYSTALLOGRAPHIC STUDIES OF PLANT VIRUS PREPARATIONS. III.

    PubMed

    Bernal, J D; Fankuchen, I

    1941-09-20

    These papers give an account of an optical and x-ray examination of preparations of plant virus substances isolated by Bawden and Pirie, in particular of those of tobacco mosaic disease. They open with a historical survey of the work, indicating the order in which new phenomena were discovered. The subsequent treatment is divided into three parts: I. Introduction and preparation of specimens. II. Modes of aggregation of virus particles. III. (1) The structure of the particles. (2) Biological implications. Part I, after an historical introduction, describes the method of preparation, from solutions of the virus, of optically oriented specimens of different concentrations. For their examination special x-ray apparatus was developed, in particular cameras working with very low angles and capable of indicating spacings up to 1000 A. In Part III, Section 1 deals with the x-ray evidence on the internal structure of the particles. Even in solution, they have an inner regularity like that of a crystal. Virus preparations are thus in a sense doubly crystalline. Closer analysis reveals that the x-ray patterns are not directly comparable to those of a crystal as many of the reflections do not obey Bragg's law, but can be understood on the theory of gratings of limited size. The structure seems to consist of sub-units of the dimensions of approximately 11 A cube, fitted together in a hexagonal or pseudohexagonal lattice of dimensions-a = 87 A, c = 68 A. Contrary to what earlier observations seemed to indicate, the particle seems to be virtually unchanged by drying and must therefore contain little water. There are marked resemblances with the structure of both crystalline and fibrous protein, but the virus structure does not belong to any of the classes hitherto studied. There are indications that the inner structure is of a simpler character than that of the molecules of crystalline proteins. Part III, Section 2 contains a comparative study of the optical and x

  16. X-RAY AND CRYSTALLOGRAPHIC STUDIES OF PLANT VIRUS PREPARATIONS. III

    PubMed Central

    Bernal, J. D.; Fankuchen, I.

    1941-01-01

    These papers give an account of an optical and x-ray examination of preparations of plant virus substances isolated by Bawden and Pirie, in particular of those of tobacco mosaic disease. They open with a historical survey of the work, indicating the order in which new phenomena were discovered. The subsequent treatment is divided into three parts: I. Introduction and preparation of specimens. II. Modes of aggregation of virus particles. III. (1) The structure of the particles. (2) Biological implications. Part I, after an historical introduction, describes the method of preparation, from solutions of the virus, of optically oriented specimens of different concentrations. For their examination special x-ray apparatus was developed, in particular cameras working with very low angles and capable of indicating spacings up to 1000 Å. In Part III, Section 1 deals with the x-ray evidence on the internal structure of the particles. Even in solution, they have an inner regularity like that of a crystal. Virus preparations are thus in a sense doubly crystalline. Closer analysis reveals that the x-ray patterns are not directly comparable to those of a crystal as many of the reflections do not obey Bragg's law, but can be understood on the theory of gratings of limited size. The structure seems to consist of sub-units of the dimensions of approximately 11 Å cube, fitted together in a hexagonal or pseudohexagonal lattice of dimensions—a = 87 Å, c = 68 Å. Contrary to what earlier observations seemed to indicate, the particle seems to be virtually unchanged by drying and must therefore contain little water. There are marked resemblances with the structure of both crystalline and fibrous protein, but the virus structure does not belong to any of the classes hitherto studied. There are indications that the inner structure is of a simpler character than that of the molecules of crystalline proteins. Part III, Section 2 contains a comparative study of the optical and x

  17. Beyond a climate-centric view of plant distribution: edaphic variables add value to distribution models.

    PubMed

    Beauregard, Frieda; de Blois, Sylvie

    2014-01-01

    Both climatic and edaphic conditions determine plant distribution, however many species distribution models do not include edaphic variables especially over large geographical extent. Using an exceptional database of vegetation plots (n = 4839) covering an extent of ∼55,000 km2, we tested whether the inclusion of fine scale edaphic variables would improve model predictions of plant distribution compared to models using only climate predictors. We also tested how well these edaphic variables could predict distribution on their own, to evaluate the assumption that at large extents, distribution is governed largely by climate. We also hypothesized that the relative contribution of edaphic and climatic data would vary among species depending on their growth forms and biogeographical attributes within the study area. We modelled 128 native plant species from diverse taxa using four statistical model types and three sets of abiotic predictors: climate, edaphic, and edaphic-climate. Model predictive accuracy and variable importance were compared among these models and for species' characteristics describing growth form, range boundaries within the study area, and prevalence. For many species both the climate-only and edaphic-only models performed well, however the edaphic-climate models generally performed best. The three sets of predictors differed in the spatial information provided about habitat suitability, with climate models able to distinguish range edges, but edaphic models able to better distinguish within-range variation. Model predictive accuracy was generally lower for species without a range boundary within the study area and for common species, but these effects were buffered by including both edaphic and climatic predictors. The relative importance of edaphic and climatic variables varied with growth forms, with trees being more related to climate whereas lower growth forms were more related to edaphic conditions. Our study identifies the potential

  18. Beyond a Climate-Centric View of Plant Distribution: Edaphic Variables Add Value to Distribution Models

    PubMed Central

    Beauregard, Frieda; de Blois, Sylvie

    2014-01-01

    Both climatic and edaphic conditions determine plant distribution, however many species distribution models do not include edaphic variables especially over large geographical extent. Using an exceptional database of vegetation plots (n = 4839) covering an extent of ∼55000 km2, we tested whether the inclusion of fine scale edaphic variables would improve model predictions of plant distribution compared to models using only climate predictors. We also tested how well these edaphic variables could predict distribution on their own, to evaluate the assumption that at large extents, distribution is governed largely by climate. We also hypothesized that the relative contribution of edaphic and climatic data would vary among species depending on their growth forms and biogeographical attributes within the study area. We modelled 128 native plant species from diverse taxa using four statistical model types and three sets of abiotic predictors: climate, edaphic, and edaphic-climate. Model predictive accuracy and variable importance were compared among these models and for species' characteristics describing growth form, range boundaries within the study area, and prevalence. For many species both the climate-only and edaphic-only models performed well, however the edaphic-climate models generally performed best. The three sets of predictors differed in the spatial information provided about habitat suitability, with climate models able to distinguish range edges, but edaphic models able to better distinguish within-range variation. Model predictive accuracy was generally lower for species without a range boundary within the study area and for common species, but these effects were buffered by including both edaphic and climatic predictors. The relative importance of edaphic and climatic variables varied with growth forms, with trees being more related to climate whereas lower growth forms were more related to edaphic conditions. Our study identifies the potential for

  19. Distribution, synthesis, and absorption of kynurenic acid in plants.

    PubMed

    Turski, Michal P; Turska, Monika; Zgrajka, Wojciech; Bartnik, Magdalena; Kocki, Tomasz; Turski, Waldemar A

    2011-05-01

    Kynurenic acid (KYNA) is an endogenous antagonist of the ionotropic glutamate receptors and the α7 nicotinic acetylcholine receptor as well as an agonist of the G-protein-coupled receptor GPR35. In this study, KYNA distribution and synthesis in plants as well as its absorption was researched. KYNA level was determined by means of the high-performance liquid chromatography with fluorescence detection. KYNA was found in leaves, flowers, and roots of tested medicinal herbs: dandelion (Taraxacum officinale), common nettle (Urtica dioica), and greater celandine (Chelidoniummajus). The highest concentration of this compound was detected in leaves of dandelion--a mean value of 0.49 µg/g wet weight. It was shown that KYNA can be synthesized enzymatically in plants from its precursor, L-kynurenine, or absorbed by plants from the soil. Finally, the content of KYNA was investigated in 21 herbal tablets, herbal tea, herbs in sachets, and single herbs in bags. The highest content of KYNA in a maximum daily dose of herbal medicines appeared in St. John's wort--33.75 µg (tablets) or 32.60 µg (sachets). The pharmacological properties of KYNA and its presence in high concentrations in medicinal herbs may suggest that it possesses therapeutic potential, especially in the digestive system and should be considered a new valuable dietary supplement. PMID:21157681

  20. Distributions of types I, II and III collagen by region in the human supraspinatus tendon.

    PubMed

    Buckley, Mark R; Evans, Elisabeth B; Matuszewski, Paul E; Chen, Yi-Ling; Satchel, Lauren N; Elliott, Dawn M; Soslowsky, Louis J; Dodge, George R

    2013-01-01

    The mechanical properties of the human supraspinatus tendon (SST) are highly heterogeneous and may reflect an important adaptive response to its complex, multiaxial loading environment. However, these functional properties are associated with a location-dependent structure and composition that have not been fully elucidated. Therefore, the objective of this study was to determine the concentrations of types I, II and III collagen in six distinct regions of the SST and compare changes in collagen concentration across regions with local changes in mechanical properties. We hypothesized that type I collagen content would be high throughout the tendon, type II collagen would be restricted to regions of compressive loading and type III collagen content would be high in regions associated with damage. We further hypothesized that regions of high type III collagen content would correspond to regions with low tensile modulus and a low degree of collagen alignment. Although type III collagen content was not significantly higher in regions that are frequently damaged, all other hypotheses were supported by our results. In particular, type II collagen content was highest near the insertion while type III collagen was inversely correlated with tendon modulus and collagen alignment. The measured increase in type II collagen under the coracoacromial arch provides evidence of adaptation to compressive loading in the SST. Moreover, the structure-function relationship between type III collagen content and tendon mechanics established in this study demonstrates a mechanism for altered mechanical properties in pathological tendons and provides a guideline for identifying therapeutic targets and pathology-specific biomarkers.

  1. Biological Oxidation of As (III) in a Full-Scale Iron Removal Plant

    EPA Science Inventory

    The effectiveness of arsenic removal from water is largely dependent on the oxidation state of the arsenic. As (III) is much more difficult to remove relative to the oxidized As (V) form. Arsenic in ground waters across the Midwest is typically in the form of As (III), and ther...

  2. ON THE BRIGHTNESS AND WAITING-TIME DISTRIBUTIONS OF A TYPE III RADIO STORM OBSERVED BY STEREO/WAVES

    SciTech Connect

    Eastwood, J. P.; Hudson, H. S.; Krucker, S.; Bale, S. D.; Wheatland, M. S.; Maksimovic, M.; Bougeret, J.-L.; Goetz, K.

    2010-01-10

    Type III solar radio storms, observed at frequencies below {approx}16 MHz by space-borne radio experiments, correspond to the quasi-continuous, bursty emission of electron beams onto open field lines above active regions. The mechanisms by which a storm can persist in some cases for more than a solar rotation whilst exhibiting considerable radio activity are poorly understood. To address this issue, the statistical properties of a type III storm observed by the STEREO/WAVES radio experiment are presented, examining both the brightness distribution and (for the first time) the waiting-time distribution (WTD). Single power-law behavior is observed in the number distribution as a function of brightness; the power-law index is {approx}2.1 and is largely independent of frequency. The WTD is found to be consistent with a piecewise-constant Poisson process. This indicates that during the storm individual type III bursts occur independently and suggests that the storm dynamics are consistent with avalanche-type behavior in the underlying active region.

  3. Unpreferred plants affect patch choice and spatial distribution of European brown hares

    NASA Astrophysics Data System (ADS)

    Kuijper, D. P. J.; Bakker, J. P.

    2008-11-01

    Many herbivore species prefer to forage on patches of intermediate biomass. Plant quality and forage efficiency are predicted to decrease with increasing plant standing crop which explains the lower preference of the herbivore. However, often is ignored that on the long-term, plant species composition is predicted to change with increasing plant standing crop. The amount of low-quality, unpreferred food plants increases with increasing plant standing crop. In the present study the effects of unpreferred plants on patch choice and distribution of European brown hare in a salt-marsh system were studied. In one experiment, unpreferred plants were removed from plots. In the second experiment, plots were planted with different densities of an unpreferred artificial plant. Removal of unpreferred plants increased hare-grazing pressure more than fivefold compared to unmanipulated plots. Planting of unpreferred plants reduced hare-grazing pressure, with a significant reduction of grazing already occurring at low unpreferred plant density. Spatial distribution of hares within this salt-marsh system was related to spatial arrangement of unpreferred plants. Hare-grazing intensity decreased strongly with increasing abundance of unpreferred plants despite a high abundance of principal food plants. The results of this study indicate that plant species replacement is an important factor determining patch choice and spatial distribution of hares next to changing plant quality. Increasing abundance of unpreferred plant species can strengthen the decreasing patch quality with increasing standing crop and can decrease grazing intensity when preferred food plants are still abundantly present.

  4. Interactome of the Plant-specific ESCRT-III Component AtVPS2.2 in Arabidopsis thaliana

    PubMed Central

    2011-01-01

    The endosomal sorting complexes required for transport (ESCRT) guides transmembrane proteins to domains that bud away from the cytoplasm. The ESCRT machinery consists of four complexes. ESCRT complexes 0–II are important for cargo recognition and concentration via ubiquitin binding. Most of the membrane bending function is mediated by the large multimeric ESCRT-III complex and associated proteins. Here we present the first in vivo proteome analysis of a member of the ESCRT-III complex which is unique to the plant kingdom. We show with LC–MS/MS, yeast-two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) that coimmunoprecipitated proteins from Arabidopsisthaliana roots expressing a functional GFP-tagged VACUOLAR PROTEIN SORTING 2.2 (AtVPS2.2) protein are members of the ESCRT-III complex and associated proteins. Therefore we propose that at least in plants the large ESCRT-III membrane scaffolding complex consists of a mixture of SNF7, VPS2 and the associated VPS46 and VPS60 proteins. Apart from transmembrane proteins, numerous membrane-associated but also nuclear and extracellular proteins have been identified, indicating that AtVPS2.2 might be involved in processes beyond the classical ESCRT role. This study is the first in vivo proteome analysis with a tagged ESCRT-III component demonstrating the feasibility of this approach and provides numerous starting points for the investigation of the biological process in which AtVPS2.2 is involved. PMID:22010978

  5. Abnormal collagen I to III distribution in the skin of patients with incisional hernia.

    PubMed

    Klinge, U; Si, Z Y; Zheng, H; Schumpelick, V; Bhardwaj, R S; Klosterhalfen, B

    2000-01-01

    The surgical mesh-free repair of incisional hernias has to face recurrence rates of up to 50%. Apart from technical faults this is probably due to collagen metabolic disorders, known to play an important role in the development of inguinal hernia. In particular an altered ratio of collagen types I and III with an increase in collagen type III has been claimed to reduce the mechanical strength of connective tissues. Therefore, we investigated the content of collagen types I and III in the skin of patients with incisional hernia (n = 7) and recurrent incisional hernia (n = 5) in comparison to controls with healthy skin (n = 7) and normal skin scar (n = 7) both by immunohistochemistry and Western blot analysis. Both immunohistochemistry and Western blot analysis revealed a decrease in the ratio of collagen I/III due to a concomitant increase in collagen III. The patients with incisional hernias and with recurrent incisional hernias showed a ratio of 1.0 +/- 0.1 and 0.8 +/- 0.1, respectively, whereas the controls exhibit a ratio of 2.1 +/- 0.2 in healthy skin and of 1.2 +/- 0.2 in normal skin scar, respectively. The decrease was highly significant (p < 0.01) between the patients with either primary or recurrent hernia and the controls or the normal scar, as well as between controls and normal scar, whereas there was not any significant difference between primary and recurrent hernia (p > 0.05). Our data for the first time confirmed that the presence of incisional hernia is accompanied by impaired collagen synthesis in the skin. The decreased tensile strength of collagen type III may play a key role in the development of incisional hernias. Furthermore, it might explain the high recurrence rates of hernia repair by simple closure, as a repetition of the primarily failing technique, and the improvement by the additional use of alloplastic material.

  6. Cadmium distribution and chemical fate in soybean plants

    SciTech Connect

    Cataldo, D.A.; Garland, T.R.; Wildung, R.E.

    1981-10-01

    The distribution and chemical behavior of Cd/sup 2+/ in tissues and its chemical form in xylem water of soybeam plants (cv. Williams) were investigated. Following root absorption, Cd is strongly retained by roots, with only 2% of the accumulated Cd being transported to leaves; as much as 8% was transported to seeds during seed filling. In vivo xylem exudates contained two anionic Cd complexes in addition to inorganic forms of Cd. Once accumulated in root and leaf tissues, Cd rapidly equilibrated between the insoluble, soluble, and organelle fractions. Of the solubles, which contain 50% of the Cd, >50% was associated with components of >10,000 molecular weight, and <8% was associated with <500 molecular weight components. Cadmium accumulated in soybean seeds was primarily associated with cotyledons. Fractionation of seeds showed the soy proteinate and soy whey to contain 32 and 50% of the accumulated Cd, respectively.

  7. Saguaro Power Plant Solar Repowering Project. Volume III. Appendices. Final technical report, September 1979-July 1980

    SciTech Connect

    Weber, E.R.

    1980-07-01

    The conceptual design of a central receiver power plant using a molten salt for repowering the No. One Unit of Arizona Public Service's Saguaro power plant is given. This volume of the report contains the appendices: (A) effect of Arizona Public Service Company's demand profile on the amount of storage; (B) receiver design drawings; (C) plant characteristics and performance data; (E) existing plant description; (F) economic data; (G) simulation models; (H) plant cost data; and (I) project control network. (WHK)

  8. A plant distribution shift: temperature, drought or past disturbance?

    USGS Publications Warehouse

    Schwilk, Dylan W.; Keeley, Jon E.

    2012-01-01

    Simple models of plant response to warming climates predict vegetation moving to cooler and/or wetter locations: in mountainous regions shifting upslope. However, species-specific responses to climate change are likely to be much more complex. We re-examined a recently reported vegetation shift in the Santa Rosa Mountains, California, to better understand the mechanisms behind the reported shift of a plant distribution upslope. We focused on five elevational zones near the center of the gradient that captured many of the reported shifts and which are dominated by fire-prone chaparral. Using growth rings, we determined that a major assumption of the previous work was wrong: past fire histories differed among elevations. To examine the potential effect that this difference might have on the reported upward shift, we focused on one species, Ceanothus greggii: a shrub that only recruits post-fire from a soil stored seedbank. For five elevations used in the prior study, we calculated time series of past per-capita mortality rates by counting growth rings on live and dead individuals. We tested three alternative hypotheses explaining the past patterns of mortality: 1) mortality increased over time consistent with climate warming, 2) mortality was correlated with drought indices, and 3) mortality peaked 40–50 years post fire at each site, consistent with self-thinning. We found that the sites were different ages since the last fire, and that the reported increase in the mean elevation of C. greggii was due to higher recent mortality at the lower elevations, which were younger sites. The time-series pattern of mortality was best explained by the self-thinning hypothesis and poorly explained by gradual warming or drought. At least for this species, the reported distribution shift appears to be an artifact of disturbance history and is not evidence of a climate warming effect.

  9. A plant distribution shift: temperature, drought or past disturbance?

    PubMed

    Schwilk, Dylan W; Keeley, Jon E

    2012-01-01

    Simple models of plant response to warming climates predict vegetation moving to cooler and/or wetter locations: in mountainous regions shifting upslope. However, species-specific responses to climate change are likely to be much more complex. We re-examined a recently reported vegetation shift in the Santa Rosa Mountains, California, to better understand the mechanisms behind the reported shift of a plant distribution upslope. We focused on five elevational zones near the center of the gradient that captured many of the reported shifts and which are dominated by fire-prone chaparral. Using growth rings, we determined that a major assumption of the previous work was wrong: past fire histories differed among elevations. To examine the potential effect that this difference might have on the reported upward shift, we focused on one species, Ceanothus greggii: a shrub that only recruits post-fire from a soil stored seedbank. For five elevations used in the prior study, we calculated time series of past per-capita mortality rates by counting growth rings on live and dead individuals. We tested three alternative hypotheses explaining the past patterns of mortality: 1) mortality increased over time consistent with climate warming, 2) mortality was correlated with drought indices, and 3) mortality peaked 40-50 years post fire at each site, consistent with self-thinning. We found that the sites were different ages since the last fire, and that the reported increase in the mean elevation of C. greggii was due to higher recent mortality at the lower elevations, which were younger sites. The time-series pattern of mortality was best explained by the self-thinning hypothesis and poorly explained by gradual warming or drought. At least for this species, the reported distribution shift appears to be an artifact of disturbance history and is not evidence of a climate warming effect.

  10. Modeling of the adsorptive removal of arsenic(III) using plant biomass: a bioremedial approach

    NASA Astrophysics Data System (ADS)

    Roy, Palas; Dey, Uttiya; Chattoraj, Soumya; Mukhopadhyay, Debasis; Mondal, Naba Kumar

    2015-09-01

    In the present work, the possibility of using a non-conventional finely ground (250 μm) Azadirachta indica (neem) bark powder [AiBP] has been tested as a low-cost biosorbent for the removal of arsenic(III) from water. The removal of As(III) was studied by performing a series of biosorption experiments (batch and column). The biosorption behavior of As(III) for batch and column operations were examined in the concentration ranges of 50-500 µg L-1 and 500.0-2000.0 µg L-1, respectively. Under optimized batch conditions, the AiBP could remove up to 89.96 % of As(III) in water system. The artificial neural network (ANN) model was developed from batch experimental data sets which provided reasonable predictive performance (R 2 = 0.961; 0.954) of As(III) biosorption. In batch operation, the initial As(III) concentration had the most significant impact on the biosorption process. For column operation, central composite design (CCD) was applied to investigate the influence on the breakthrough time for optimization of As(III) biosorption process and evaluation of interacting effects of different operating variables. The optimized result of CCD revealed that the AiBP was an effective and economically feasible biosorbent with maximum breakthrough time of 653.9 min, when the independent variables were retained at 2.0 g AiBP dose, 2000.0 µg L-1 initial As(III) concentrations, and 3.0 mL min-1 flow rate, at maximum desirability value of 0.969.

  11. Subcellular distribution and chemical form of cadmium in bean plants

    SciTech Connect

    Weigel, H.J.; Jaeger, H.J.

    1980-03-01

    The subcellular distribution and chemical form of Cd in bean plants grown in nutrient solutions containing Cd were investigated. Cd was accumulated mainly in roots and to a minor extent in leaves. Subcellular fractionation of Cd-containing tissues (pH 7.5) showed that more than 70% of the element was localized in the cytoplasmic fraction in roots as well as in leaves. Little Cd (8 to 14%) was bound either to the cell wall fraction or to the organelles. Gel filtration of the soluble fraction showed Cd to be associated mainly with 5000 to 10,000 molecular weight components in roots, and 700 to 5000 molecular weight components in leaves. Small amounts of Cd were found in the high molecular weight proteins (molecular weight 150,000). Only traces of Cd could be detected as a free ion. Chemical characterization of the low molecular weight components resulted in the identification of nine amino acids which were identical in roots and leaves. Cd in bean plants is assumed to be bound to peptides and/or proteins of low molecular weight.

  12. Fuel cell power plants in a distributed generator application

    SciTech Connect

    Smith, M.J.

    1996-12-31

    ONSI`s (a subsidiary of International Fuel Cells Corporation) world wide fleet of 200-kW PC25{trademark} phosphoric acid fuel cell power plants which began operation early in 1992 has shown excellent performance and reliability in over 1 million hours of operation. This experience has verified the clean, quiet, reliable operation of the PC25 and confirmed its application as a distributed generator. Continuing product development efforts have resulted in a one third reduction of weight and volume as well as improved installation and operating characteristics for the PC25 C model. Delivery of this unit began in 1995. International Fuel Cells (IFC) continues its efforts to improve product design and manufacturing processes. This progress has been sustained at a compounded rate of 10 percent per year since the late 1980`s. These improvements will permit further reductions in the initial cost of the power plant and place increased emphasis on market development as the pacing item in achieving business benefits from the PC25 fuel cell. Derivative product opportunities are evolving with maturation of the technologies in a commercial environment. The recent announcement of Praxair, Inc., and IFC introducing a non-cryogenic hydrogen supply system utilizing IFC`s steam reformer is an example. 11 figs.

  13. Alaska Melilotus invasions: Distribution, origin, and susceptibility of plant communities

    USGS Publications Warehouse

    Conn, J.S.; Beattie, K.L.; Shephard, M.A.; Carlson, M.L.; Lapina, I.; Hebert, M.; Gronquist, R.; Densmore, R.; Rasy, M.

    2008-01-01

    Melilotus alba and M. officinalis were introduced to Alaska in 1913 as potential forage crops. These species have become naturalized and are now invading large, exotic plant-free regions of Alaska. We determined distributions of M. alba and M. officinalis in Alaska from surveys conducted each summer from 2002 to 2005. Melilotus alba and M. officinalis occurred at 721 and 205 sites, respectively (39,756 total sites surveyed). The northward limit for M. alba and M. officinalis was 67.15??N and 64.87??N, respectively. Both species were strictly associated with soil disturbance. Melilotus alba extended no farther than 15 m from road edges except where M. alba on roadsides met river floodplains and dispersed downriver (Matanuska and Nenana Rivers). Melilotus has now reached the Tanana River, a tributary of the Yukon River. Populations on floodplains were most extensive on braided sections. On the Nenana River, soil characteristics did not differ between where M. alba was growing versus similar areas where it had not yet reached. The pH of river soils (7.9-8.3) was higher than highway soils (7.3). Upland taiga plant communities grow on acid soils which may protect them from invasion by Melilotus, which prefer alkaline soils; however, early succession communities on river floodplains are susceptible because soils are alkaline. ?? 2008 Regents of the University of Colorado.

  14. Properties of Higher Plant Mitochondria. III. Effects of Respiratory Inhibitors 1

    PubMed Central

    Ikuma, Hiroshi; Bonner, Walter D.

    1967-01-01

    The effects of representative respiratory inhibitors were investigated on the coupled respiration of mung bean mitochondria using succinate and l-malate as substrates. The inhibitors studied were: (I) malonate, (II) amytal and rotenone, (III) antimycin A and 2-n-nonyl-4-hydroxyquinoline N-oxide (NOQNO), and (IV) cyanide and azide. Malonate inhibition of succinate oxidation follows a classical type of competitive inhibition with an inhibitor dissociation constant of 0.13 mm. There is no inhibition detectable when malate is used as substrate. In contrast to animal mitochondria, amytal is capable of inhibiting 20 to 40% of succinate oxidation and 90 to 100% of malate oxidation, but inhibition due to rotenone amounts to only 0 to 20% of succinate oxidation and 40 to 50% of malate oxidation. The half-maximal inhibition caused by amytal occurs at 2 to 2.5 mm and that by rotenone at 3 mμmoles/mg protein. The maximal inhibition caused by either antimycin A or NOQNO is 70 to 80% of the state 3 respiration. Very little inhibition was observed on the state 4 respiration, and both inhibitors were capable of titrating stoichiometrically with mitochondrial protein with identical titers, 0.22 mμmoles/mg protein for half-maximal inhibition. They differ, however, in that NOQNO does uncouple oxidative phosphorylation in mung bean mitochondria, but antimycin A does not do so. Both cyanide and azide inhibit the state 3 rate 65 to 80%. Inhibition of state 4 respiration can be up to 50% by cyanide, while almost none by azide. Uncoupling action was noted with cyanide, but very little with azide. It is concluded that the second state 3 rate of succinate oxidation includes 80% succinoxidase, the remaining 20% being contributed by the NADH pathway. Malate oxidation apparently does not involve succinoxidase. Malate oxidation is completely sensitive to amytal, but only 50% inhibited by rotenone. A difference between animal and plant mitochondria appears to be in the flavoproteins associated

  15. Distribution of Groundwater Contaminants at the RCA Taoyuan Plant

    NASA Astrophysics Data System (ADS)

    Yao, I.; Wang, Y.; Chia, Y.

    2013-12-01

    The RCA Taoyuan plant is the first announced remediation site due to groundwater contamination in Taiwan in 2004. From 1970 through 1992, Radio Corporation of America (RCA) Taoyuan Plant in Taiwan operated as a television assembly plant producing related electronic equipment. In 1987, the soil and the groundwater of the site area were discovered with contamination of chlorinated Volatile Organic Compounds (VOCs). The primary contaminants are tetrachloroethene (PCE), trichloroethene (TCE), and 1, 1, 1- trichloroethane (1, 1, 1-TCA). The source of the contamination may be caused by improper dumping or leakage of the chemical solvents. The remediation of soil were finished in 1998 and qualified with Republic of China Environmental Protection Administration (ROCEPA) soil pollution control standards. On the other hand, after more detailed site investigations and many pilot tests, the remediation of groundwater has been started since 2005 and is still in progress. Because the chlorinated VOCs are Dense Non-Aqueous Phase Liquids (DNAPLs), they are hardly dissolved in groundwater and couldn't be cleaned up by extraction and treatment. In addition, the densities of DNAPLs are higher than water, so they would keep moving downward till aquitards or interval mud layers between aquifers. The movement was controlled by many complex factors, including the gravity, hydraulic gradient, capillary pressure, etc. Then DNAPLs would move along the surface of layers horizontally leaving slight remains on the paths. The remains would keep slowly dissolving in groundwater to become long-term contamination sources. The Enhanced Reductive Dechlorination (ERD) method has been conducted to remediate the groundwater in site area with successful effects, but some of the monitoring wells in off-site area are still detected with high concentrations of VOCs, exceeding the pollution standards. Furthermore, the concentration of primary contaminants was lowered by the remediation, but some secondary

  16. The xylanase inhibitor TAXI-III counteracts the necrotic activity of a Fusarium graminearum xylanase in vitro and in durum wheat transgenic plants.

    PubMed

    Moscetti, Ilaria; Faoro, Franco; Moro, Stefano; Sabbadin, Davide; Sella, Luca; Favaron, Francesco; D'Ovidio, Renato

    2015-08-01

    The xylanase inhibitor TAXI-III has been proven to delay Fusarium head blight (FHB) symptoms caused by Fusarium graminearum in transgenic durum wheat plants. To elucidate the molecular mechanism underlying the capacity of the TAXI-III transgenic plants to limit FHB symptoms, we treated wheat tissues with the xylanase FGSG_03624, hitherto shown to induce cell death and hydrogen peroxide accumulation. Experiments performed on lemmas of flowering wheat spikes and wheat cell suspension cultures demonstrated that pre-incubation of xylanase FGSG_03624 with TAXI-III significantly decreased cell death. Most interestingly, a reduced cell death relative to control non-transgenic plants was also obtained by treating, with the same xylanase, lemmas of TAXI-III transgenic plants. Molecular modelling studies predicted an interaction between the TAXI-III residue H395 and residues E122 and E214 belonging to the active site of xylanase FGSG_03624. These results provide, for the first time, clear indications in vitro and in planta that a xylanase inhibitor can prevent the necrotic activity of a xylanase, and suggest that the reduced FHB symptoms on transgenic TAXI-III plants may be a result not only of the direct inhibition of xylanase activity secreted by the pathogen, but also of the capacity of TAXI-III to avoid host cell death.

  17. Plant-derived juvenile hormone III analogues and other sesquiterpenes from the stem bark of Cananga latifolia.

    PubMed

    Yang, Heejung; Kim, Hye Seong; Jeong, Eun Ju; Khiev, Piseth; Chin, Young-Won; Sung, Sang Hyun

    2013-10-01

    Juvenile hormone III (JH III) is a larval metamorphosis-regulating hormone present in most insect species. JH III was first isolated from the plant, Cyperus iria L., but the presence of JH III has not been reported in other plant species. In the present study, proof of the existence of JH III and its analogues from Cananga latifolia was established. From an aqueous MeOH extract of C. latifolia stem bark, six compounds were isolated along with nine known compounds. These were identified by using spectroscopic analyses as: (2E,6E,10R)-11-butoxy-10-hydroxy-3,7,11-trimethyldodeca-2,6-dienoic acid methyl ester, (2E,6E)-3,7,11-trimethyl-10-oxododeca-2,6-dienoic acid methyl ester, (2E)-3-methyl-5-[(1S,2R,6R)-1,2,6-trimethyl-3-oxocyclohexyl]-pent-2-enoic acid methyl ester, 1β-hydroxy-3-oxo-4β, 5α,7α-H-eudesmane 11-O-α-l-rhamnopyranoside, 4-epi-aubergenone 11-O-2',3'-di-O-acetyl-α-l-rhamnopyranoside and 4-epi-aubergenone 11-O-2',4'-di-O-acetyl-α-l-rhamnopyranoside. Three of the previously known compounds, (2E,6E,10R)-10-hydroxy-3,7,11-trimethyldodeca-2,6,11-trienoaic acid methyl ester, (2E,6E,10R)-10,11-dihydroxy-3,7,11-trimethyldodeca-2,6-dienoic acid and (2E,6S)-3-methyl-6-hydroxy-6-[(2R,5R)-5-(2-hydroxypropan-2-yl)-2-methyltetrahydrofuran-2-yl]-hex-2-enoaic acid methyl ester have now been found in a plant species. Ultra performance liquid chromatography-quadruple time-of-flight mass spectroscopy (UPLC-QTOF/MS) analysis of the chemical constituents of C. latifolia showed that several were predominant in the sub-fractions of a C. latifolia stem bark extract.

  18. Plant-derived juvenile hormone III analogues and other sesquiterpenes from the stem bark of Cananga latifolia.

    PubMed

    Yang, Heejung; Kim, Hye Seong; Jeong, Eun Ju; Khiev, Piseth; Chin, Young-Won; Sung, Sang Hyun

    2013-10-01

    Juvenile hormone III (JH III) is a larval metamorphosis-regulating hormone present in most insect species. JH III was first isolated from the plant, Cyperus iria L., but the presence of JH III has not been reported in other plant species. In the present study, proof of the existence of JH III and its analogues from Cananga latifolia was established. From an aqueous MeOH extract of C. latifolia stem bark, six compounds were isolated along with nine known compounds. These were identified by using spectroscopic analyses as: (2E,6E,10R)-11-butoxy-10-hydroxy-3,7,11-trimethyldodeca-2,6-dienoic acid methyl ester, (2E,6E)-3,7,11-trimethyl-10-oxododeca-2,6-dienoic acid methyl ester, (2E)-3-methyl-5-[(1S,2R,6R)-1,2,6-trimethyl-3-oxocyclohexyl]-pent-2-enoic acid methyl ester, 1β-hydroxy-3-oxo-4β, 5α,7α-H-eudesmane 11-O-α-l-rhamnopyranoside, 4-epi-aubergenone 11-O-2',3'-di-O-acetyl-α-l-rhamnopyranoside and 4-epi-aubergenone 11-O-2',4'-di-O-acetyl-α-l-rhamnopyranoside. Three of the previously known compounds, (2E,6E,10R)-10-hydroxy-3,7,11-trimethyldodeca-2,6,11-trienoaic acid methyl ester, (2E,6E,10R)-10,11-dihydroxy-3,7,11-trimethyldodeca-2,6-dienoic acid and (2E,6S)-3-methyl-6-hydroxy-6-[(2R,5R)-5-(2-hydroxypropan-2-yl)-2-methyltetrahydrofuran-2-yl]-hex-2-enoaic acid methyl ester have now been found in a plant species. Ultra performance liquid chromatography-quadruple time-of-flight mass spectroscopy (UPLC-QTOF/MS) analysis of the chemical constituents of C. latifolia showed that several were predominant in the sub-fractions of a C. latifolia stem bark extract. PMID:23859262

  19. Soil, plant, and terrain effects on natural perchlorate distribution in a desert landscape

    USGS Publications Warehouse

    Andraski, Brian J.; Jackson, W.A.; Welborn, Toby L.; Böhlke, John Karl; Sevanthi, Ritesh; Stonestrom, David A.

    2014-01-01

    Perchlorate (ClO4−) is a contaminant that occurs naturally throughout the world, but little is known about its distribution and interactions in terrestrial ecosystems. The objectives of this Amargosa Desert, Nevada study were to determine (i) the local-scale distribution of shallow-soil (0–30 cm) ClO4− with respect to shrub proximity (far and near) in three geomorphic settings (shoulder slope, footslope, and valley floor); (ii) the importance of soil, plant, and terrain variables on the hillslope-distribution of shallow-soil and creosote bush [Larrea tridentata (Sessé & Moc. ex DC.) Coville] ClO4−; and (iii) atmospheric (wet plus dry, including dust) deposition of ClO4− in relation to soil and plant reservoirs and cycling. Soil ClO4− ranged from 0.3 to 5.0 μg kg−1. Within settings, valley floor ClO4− was 17× less near shrubs due in part to enhanced leaching, whereas shoulder and footslope values were ∼2× greater near shrubs. Hillslope regression models (soil, R2 = 0.42; leaf, R2 = 0.74) identified topographic and soil effects on ClO4− deposition, transport, and cycling. Selective plant uptake, bioaccumulation, and soil enrichment were evidenced by leaf ClO4− concentrations and Cl−/ClO4− molar ratios that were ∼8000× greater and 40× less, respectively, than soil values. Atmospheric deposition ClO4− flux was 343 mg ha−1 yr−1, ∼10× that for published southwestern wet-deposition fluxes. Creosote bush canopy ClO4− (1310 mg ha−1) was identified as a previously unrecognized but important and active reservoir. Nitrate δ18O analyses of atmospheric deposition and soil supported the leaf-cycled–ClO4− input hypothesis. This study provides basic data on ClO4− distribution and cycling that are pertinent to the assessment of environmental impacts in desert ecosystems and broadly transferable to anthropogenically contaminated systems.

  20. Distribution of Resistant Esophageal Adenocarcinoma in the Resected Specimens of Clinical Stage III Patients After Chemoradiation: Its Clinical Implications

    PubMed Central

    Neishaboori, Nastaran; Wadhwa, Roopma; Nogueras-González, Graciela M.; Elimova, Elena; Shiozaki, Hironori; Sudo, Kazuki; Charalampakis, Nikolaos; Hiremath, Adarsh; Lee, Jeffrey H.; Bhutani, Manoop S.; Weston, Brian; Blum, Mariela A.; Rogers, Jane E.; Garris, Jeana L.; Rice, David C.; Komaki, Ritsuko; Swisher, Stephen G.; Skinner, Heath D.; Hofstetter, Wayne L.; Ajani, Jaffer A.

    2015-01-01

    Background We have limited knowledge of the geographic distribution of resistant EAC in the resected specimen and its clinical importance can be enormous. Method We selected patients with baseline stage III EAC who had chemoradiation followed by surgery, and had residual EAC (resistant cases only). Outcomes were correlated with various endpoints (% of resistant EAC, anatomic distribution). Results 100 clinical stage III patients were studied. 90% had an R0 resection. 99% had either moderate or poorly differentiated EAC. 12% had >50% residual cancer, 31% had 11–50% residual cancer, 53% had 1–10% residual cancer, and 3% had positive nodes only. Each compartment was frequently involved: mucosa/submucosa=66%, muscularis propria=76%, serosa=62%, and all=35%. Lack of EAC (meaning response) was observed in mucosa/submucosa (34%), muscularis propria (24%), serosa (38%), and nodes (42%). Although the endoscopic biopsies prior to surgery had no EAC in 79% of patients, in the surgical specimen, however, resistant EAC was frequent (66%) in mucosa/submucosa. Conclusion Contrary to our belief that resistant EAC would be frequent in the nodes, our data show that its distribution is heterogeneous and unpredictable. Most importantly, the post-chemoradiation biopsies are misleading and a decision to delay/avoid surgery based on negative biopsies can be detrimental for the patients. PMID:25765719

  1. Fabrication and optical properties of non-polar III-nitride air-gap distributed Bragg reflector microcavities

    SciTech Connect

    Tao, Renchun Kako, Satoshi; Arita, Munetaka; Arakawa, Yasuhiko

    2013-11-11

    Using the thermal decomposition technique, non-polar III-nitride air-gap distributed Bragg reflector (DBR) microcavities (MCs) with a single quantum well have been fabricated. Atomic force microscopy reveals a locally smooth DBR surface, and room-temperature micro-photoluminescence measurements show cavity modes. There are two modes per cavity due to optical birefringence in the non-polar MCs, and a systematic cavity mode shift with cavity thickness was also observed. Although the structures consist of only 3 periods (top) and 4 periods (bottom), a quality factor of 1600 (very close to the theoretical value of 2100) reveals the high quality of the air-gap DBR MCs.

  2. Flight Performance of a Jet Power Plant. III; operating characteristics of a jet power plant as a function of altitude

    NASA Technical Reports Server (NTRS)

    Weinig, F.

    1951-01-01

    The performance of a jet power plant consisting of a compressor and a turbine is determined by the characteristic curves of these component parts and is controllable by the characteristics of the compressor and the turbine i n relation t o each other. The normal. output, overload, and throttled load of the Jet power plant are obtained on the basis of assumed straight-line characteristics.

  3. In-plant demonstration of optimization of energy utilization in beck dyeing of carpet. Proposed Part III, Phase III extension of DOE contract

    SciTech Connect

    1981-01-01

    A proposal to demonstrate on a commercial scale an optimized procedure for beck dyeing of carpet to improve energy utilization is discussed. The proposal is for Phase III. A number of energy conserving procedural and equipment modification including lower dyeing temperature, lower liquor ratio, lower air exhaust flows, and recycle of hot spent dyebaths will be demonstrated in the plant dyeings. Pilot-scale experiments suggest that these modifications will reduce direct energy consumption in carpet dyeing by 400 Btu per pound of carpet processed. Adoption of the modified process by only 50% of the carpet industry would yield an annual reduction in energy consumption of 1 x 10/sup 12/ Btu's (1.7 x 10/sup 5/ BOE). The pilot-scale experiments also indicate that a cost savings of approximately 2 cents per pound of carpet dyed can be achieved with the suggested modifications. The demonstrated technology will have application in other types of nylon and polyester fiber dyeing. The Salem Carpet Mills carpet dyeing facility at Chickamauga, Georgia, will be the site of the demonstration.

  4. Pantoea agglomerans: a mysterious bacterium of evil and good. Part III. Deleterious effects: infections of humans, animals and plants.

    PubMed

    Dutkiewicz, Jacek; Mackiewicz, Barbara; Kinga Lemieszek, Marta; Golec, Marcin; Milanowski, Janusz

    2016-06-01

    (Arrhenatherum elatius). Some plant-pathogenic strains of P. agglomerans are tumourigenic, inducing gall formation on table beet, an ornamental plant gypsophila (Gypsophila paniculata), wisteria, Douglas-fir and cranberry. Recently, a Pantoea species closely related to P. agglomerans has been identified as a cause of bacterial blight disease in the edible mushroom Pleurotus eryngii cultivated in China. The genetically governed determinants of plant pathogenicity in Pantoea agglomerans include such mechanisms as the hypersensitive response and pathogenicity (hrp) system, phytohormones, the quorum-sensing (QS) feedback system and type III secretion system (T3SS) injecting the effector proteins into the cytosol of a plant cell. PMID:27294620

  5. Ralstonia solanacearum Type III Effector RipAY Is a Glutathione-Degrading Enzyme That Is Activated by Plant Cytosolic Thioredoxins and Suppresses Plant Immunity

    PubMed Central

    Hatanaka, Tadashi; Nakano, Masahito; Oda, Kenji

    2016-01-01

    ABSTRACT The plant pathogen Ralstonia solanacearum uses a large repertoire of type III effector proteins to succeed in infection. To clarify the function of effector proteins in host eukaryote cells, we expressed effectors in yeast cells and identified seven effector proteins that interfere with yeast growth. One of the effector proteins, RipAY, was found to share homology with the ChaC family proteins that function as γ-glutamyl cyclotransferases, which degrade glutathione (GSH), a tripeptide that plays important roles in the plant immune system. RipAY significantly inhibited yeast growth and simultaneously induced rapid GSH depletion when expressed in yeast cells. The in vitro GSH degradation activity of RipAY is specifically activated by eukaryotic factors in the yeast and plant extracts. Biochemical purification of the yeast protein identified that RipAY is activated by thioredoxin TRX2. On the other hand, RipAY was not activated by bacterial thioredoxins. Interestingly, RipAY was activated by plant h-type thioredoxins that exist in large amounts in the plant cytosol, but not by chloroplastic m-, f-, x-, y- and z-type thioredoxins, in a thiol-independent manner. The transient expression of RipAY decreased the GSH level in plant cells and affected the flg22-triggered production of reactive oxygen species (ROS) and expression of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) marker genes in Nicotiana benthamiana leaves. These results indicate that RipAY is activated by host cytosolic thioredoxins and degrades GSH specifically in plant cells to suppress plant immunity. PMID:27073091

  6. Ab initio calculations of the Fe(II) and Fe(III) isotopic effects in citrates, nicotianamine, and phytosiderophore, and new Fe isotopic measurements in higher plants

    NASA Astrophysics Data System (ADS)

    Moynier, Frédéric; Fujii, Toshiyuki; Wang, Kun; Foriel, Julien

    2013-05-01

    Iron is one of the most abundant transition metal in higher plants and variations in its isotopic compositions can be used to trace its utilization. In order to better understand the effect of plant-induced isotopic fractionation on the global Fe cycling, we have estimated by quantum chemical calculations the magnitude of the isotopic fractionation between different Fe species relevant to the transport and storage of Fe in higher plants: Fe(II)-citrate, Fe(III)-citrate, Fe(II)-nicotianamine, and Fe(III)-phytosiderophore. The ab initio calculations show firstly, that Fe(II)-nicotianamine is ˜3‰ (56Fe/54Fe) isotopically lighter than Fe(III)-phytosiderophore; secondly, even in the absence of redox changes of Fe, change in the speciation alone can create up to ˜1.5‰ isotopic fractionation. For example, Fe(III)-phytosiderophore is up to 1.5‰ heavier than Fe(III)-citrate2 and Fe(II)-nicotianamine is up to 1‰ heavier than Fe(II)-citrate. In addition, in order to better understand the Fe isotopic fractionation between different plant components, we have analyzed the iron isotopic composition of different organs (roots, seeds, germinated seeds, leaves and stems) from six species of higher plants: the dicot lentil (Lens culinaris), and the graminaceous monocots Virginia wild rye (Elymus virginicus), Johnsongrass (Sorghum halepense), Kentucky bluegrass (Poa pratensis), river oat (Uniola latifolia), and Indian goosegrass (Eleusine indica). The calculations may explain that the roots of strategy-II plants (Fe(III)-phytosiderophore) are isotopically heavier (by about 1‰ for the δ56Fe) than the upper parts of the plants (Fe transported as Fe(III)-citrate in the xylem or Fe(II)-nicotianamine in the phloem). In addition, we suggest that the isotopic variations observed between younger and older leaves could be explained by mixing of Fe received from the xylem and the phloem.

  7. Subcellular distribution of small interfering RNA: directed delivery through RNA polymerase III expression cassettes and localization by in situ hybridization.

    PubMed

    Paul, Cynthia P

    2005-01-01

    Reduction in the expression of specific genes through small interfering RNAs (siRNAs) is dependent on the colocalization of siRNAs with other components of the RNA interference (RNAi) pathways within the cell. The expression of siRNAs within cells from cassettes that are derived from genes transcribed by RNA polymerase III (pol III) and provide for selective subcellular distribution of their products can be used to direct siRNAs to the cellular pathways. Expression from the human U6 promoter, resulting in siRNA accumulation in the nucleus, is effective in reducing gene expression, whereas cytoplasmic and nucleolar localization of the siRNA when expressed from the 5S or 7 SL promoters is not effective. The distribution of siRNA within the cell is determined by fluorescence in situ hybridization. Although the long uninterrupted duplex of siRNA makes it difficult to detect with DNA oligonucleotide probes, labeled oligonucleotide probes with 2'-O-methyl RNA backbones provide the stability needed for a strong signal. These methods contribute to studies of the interconnected cellular RNAi pathways and are useful in adapting RNAi as a tool to determine gene function and develop RNA-based therapeutics. PMID:15644179

  8. COSTING MODELS FOR WATER SUPPLY DISTRIBUTION: PART III- PUMPS, TANKS, AND RESERVOIRS

    EPA Science Inventory

    Distribution systems are generally designed to ensure hydraulic reliability. Storage tanks, reservoirs and pumps are critical in maintaining this reliability. Although storage tanks, reservoirs and pumps are necessary for maintaining adequate pressure, they may also have a negati...

  9. Exploring high throughput phenotyping, plant architecture and plant-boll distribution for improving drought tolerance in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a pressing need to identify and understand the effects of different irrigation regimes on plant-boll distribution, seed cotton yield, and plant architecture for improving yield and fiber quality under stress and/or drought tolerance of cotton (Gossypium spp.) cultivars. To identify the impa...

  10. Pseudomonas syringae type III effector HopAF1 suppresses plant immunity by targeting methionine recycling to block ethylene induction

    PubMed Central

    Washington, Erica J.; Mukhtar, M. Shahid; Finkel, Omri M.; Wan, Li; Kieber, Joseph J.; Dangl, Jeffery L.

    2016-01-01

    HopAF1 is a type III effector protein of unknown function encoded in the genomes of several strains of Pseudomonas syringae and other plant pathogens. Structural modeling predicted that HopAF1 is closely related to deamidase proteins. Deamidation is the irreversible substitution of an amide group with a carboxylate group. Several bacterial virulence factors are deamidases that manipulate the activity of specific host protein substrates. We identified Arabidopsis methylthioadenosine nucleosidase proteins MTN1 and MTN2 as putative targets of HopAF1 deamidation. MTNs are enzymes in the Yang cycle, which is essential for the high levels of ethylene biosynthesis in Arabidopsis. We hypothesized that HopAF1 inhibits the host defense response by manipulating MTN activity and consequently ethylene levels. We determined that bacterially delivered HopAF1 inhibits ethylene biosynthesis induced by pathogen-associated molecular patterns and that Arabidopsis mtn1 mtn2 mutant plants phenocopy the effect of HopAF1. Furthermore, we identified two conserved asparagines in MTN1 and MTN2 from Arabidopsis that confer loss of function phenotypes when deamidated via site-specific mutation. These residues are potential targets of HopAF1 deamidation. HopAF1-mediated manipulation of Yang cycle MTN proteins is likely an evolutionarily conserved mechanism whereby HopAF1 orthologs from multiple plant pathogens contribute to disease in a large variety of plant hosts. PMID:27274076

  11. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 3. Appendices, Part 1

    SciTech Connect

    Mouradian, E. M.

    1983-12-31

    Thermal analyses for the preliminary design phase of the Receiver of the Carrizo Plains Solar Power Plant are presented. The sodium reference operating conditions (T/sub in/ = 610/sup 0/F, T/sub out/ = 1050/sup 0/F) have been considered. Included are: Nominal flux distribution on receiver panal, Energy input to tubes, Axial temperature distribution; sodium and tubes, Sodium flow distribution, Sodium pressure drop, orifice calculations, Temperature distribution in tube cut (R-0), Backface structure, and Nonuniform sodium outlet temperature. Transient conditions and panel front face heat losses are not considered. These are to be addressed in a subsequent design phase. Also to be considered later are the design conditions as variations from the nominal reference (operating) condition. An addendum, designated Appendix C, has been included describing panel heat losses, panel temperature distribution, and tube-manifold joint thermal model.

  12. H-coal pilot plant. Phase II. Construction. Phase III. Operation. Annual report No. 3

    SciTech Connect

    Not Available

    1981-02-04

    At the request of DOE Oak Ridge, ASFI agreed to assume responsibility for completion of Plant construction in December, 1979, at which time Badger Plants' on-site work was ended. This construction effort consisted of electric heat tracing and insulation of piping and instrumentation. At the close of the reporting period the work was completed, or was projected to be completed, within the ASFI budgeted amounts and by dates that will not impact Plant operations. Engineering design solutions were completed for problems encountered with such equipment as the High Pressure Letdown Valves; Slurry Block Valves; Slurry Pumps; the Bowl Mill System; the Dowtherm System; and the Ebullating Pump. A Corrosion Monitoring Program was established. With the exception of Area 500, the Antisolvent Deashing Unit, all operating units were commissioned and operated during the reporting period. Coal was first introduced into the Plant on May 29, 1980, with coal operations continuing periodically through September 30, 1980. The longest continuous coal run was 119 hours. A total of 677 tons of Kentucky No. 11 Coal were processed during the reporting period. The problems encountered were mechanical, not process, in nature. Various Environmental and Health programs were implemented to assure worker safety and protection and to obtain data from Plant operations for scientific analysis. These comprehensive programs will contribute greatly in determining the acceptability of long term H-Coal Plant operations.

  13. Key steps in type III secretion system (T3SS) towards translocon assembly with potential sensor at plant plasma membrane.

    PubMed

    Ji, Hongtao; Dong, Hansong

    2015-09-01

    Many plant- and animal-pathogenic Gram-negative bacteria employ the type III secretion system (T3SS) to translocate effector proteins from bacterial cells into the cytosol of eukaryotic host cells. The effector translocation occurs through an integral component of T3SS, the channel-like translocon, assembled by hydrophilic and hydrophobic proteinaceous translocators in a two-step process. In the first, hydrophilic translocators localize to the tip of a proteinaceous needle in animal pathogens, or a proteinaceous pilus in plant pathogens, and associate with hydrophobic translocators, which insert into host plasma membranes in the second step. However, the pilus needs to penetrate plant cell walls in advance. All hydrophilic translocators so far identified in plant pathogens are characteristic of harpins: T3SS accessory proteins containing a unitary hydrophilic domain or an additional enzymatic domain. Two-domain harpins carrying a pectate lyase domain potentially target plant cell walls and facilitate the penetration of the pectin-rich middle lamella by the bacterial pilus. One-domain harpins target plant plasma membranes and may play a crucial role in translocon assembly, which may also involve contrapuntal associations of hydrophobic translocators. In all cases, sensory components in the target plasma membrane are indispensable for the membrane recognition of translocators and the functionality of the translocon. The conjectural sensors point to membrane lipids and proteins, and a phosphatidic acid and an aquaporin are able to interact with selected harpin-type translocators. Interactions between translocators and their sensors at the target plasma membrane are assumed to be critical for translocon assembly.

  14. THE NATURE OF STARBURSTS. III. THE SPATIAL DISTRIBUTION OF STAR FORMATION

    SciTech Connect

    McQuinn, Kristen B. W.; Skillman, Evan D.; Dalcanton, Julianne J.; Weisz, Daniel R.; Williams, Benjamin F.; Cannon, John M.; Dolphin, Andrew E.; Holtzman, Jon

    2012-11-01

    We map the spatial distribution of recent star formation over a few Multiplication-Sign 100 Myr timescales in 15 starburst dwarf galaxies using the location of young blue helium burning stars identified from optically resolved stellar populations in archival Hubble Space Telescope observations. By comparing the star formation histories from both the high surface brightness central regions and the diffuse outer regions, we measure the degree to which the star formation has been centrally concentrated during the galaxies' starbursts, using three different metrics for the spatial concentration. We find that the galaxies span a full range in spatial concentration, from highly centralized to broadly distributed star formation. Since most starbursts have historically been identified by relatively short timescale star formation tracers (e.g., H{alpha} emission), there could be a strong bias toward classifying only those galaxies with recent, centralized star formation as starbursts, while missing starbursts that are spatially distributed.

  15. Effects of microgravity on growth hormone concentration and distribution in plants

    NASA Technical Reports Server (NTRS)

    Schulze, Aga; Jensen, Philip; Desrosiers, Mark; Bandurski, Robert S.

    1989-01-01

    On earth, gravity affects the distribution of the plant growth hormone, indole-3-acetic acid (IAA), in a manner such that the plant grows into a normal vertical orientation (shoots up, roots down). How the plant controls the amount and distribution of IAA is only partially understood and is currently under investigation in this laboratory. The question to be answered in the flight experiment concerns the effect of gravity on the concentration, turn over, and distribution of the growth hormone. The answer to this question will aid in understanding the mechanism by which plants control the amount and distribution of growth hormone. Such knowledge of a plant's hormonal metabolism may aid in the growth of plants in space and will lead to agronomic advances.

  16. Atmospheric Test Models and Numerical Experiments for the Simulation of the Global Distributions of Weather Data Transponders III. Horizontal Distributions

    SciTech Connect

    Molenkamp, C.R.; Grossman, A.

    1999-12-20

    A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show that reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.

  17. Molecular signals required for type III secretion and translocation of the Xanthomonas campestris AvrBs2 protein to pepper plants.

    PubMed

    Mudgett, M B; Chesnokova, O; Dahlbeck, D; Clark, E T; Rossier, O; Bonas, U; Staskawicz, B J

    2000-11-21

    Strains of Xanthomonas campestris pv. vesicatoria (Xcv) carrying avrBs2 are specifically recognized by Bs2 pepper plants, resulting in localized cell death and plant resistance. Agrobacterium-mediated transient expression of the Xcv avrBs2 gene in plant cells results in Bs2-dependent cell death, indicating that the AvrBs2 protein alone is sufficient for the activation of disease resistance-mediated cell death in planta. We now provide evidence that AvrBs2 is secreted from Xcv and that secretion is type III (hrp) dependent. N- and C-terminal deletion analysis of AvrBs2 has identified the effector domain of AvrBs2 recognized by Bs2 pepper plants. By using a truncated Pseudomonas syringae AvrRpt2 effector reporter devoid of type III signal sequences, we have localized the minimal region of AvrBs2 required for type III secretion in Xcv. Furthermore, we have identified the region of AvrBs2 required for both type III secretion and translocation to host plants. The mapping of AvrBs2 sequences sufficient for type III delivery also revealed the presence of a potential mRNA secretion signal. PMID:11078519

  18. Manufacturing, Marketing and Distribution, Business and Office Occupations: Grade 8. Cluster III.

    ERIC Educational Resources Information Center

    Calhoun, Olivia H.

    A curriculum guide for grade 8, the document is divided into eleven units: marketing and distribution; food manufacturing; data processing and automation; administration, management, and labor; secretarial and clerical services; office machines; equipment; metal manufacturing and processing; prefabrication and prepackaging; textile and clothing…

  19. Anthocyanins: Analysis and Distribution in Selected Medicinal Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are water soluble plant secondary metabolites responsible for the blue, purple, and red color of many plant tissues. They have been shown to be strong antioxidants, and may exert a wide range of health benefits through antioxidant or other mechanisms. Anthocyanins occur primarily as gly...

  20. Anthocyanins: analysis and distribution in selected medicinal plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are water soluble plant secondary metabolites responsible for the blue, purple, and red color of many plant tissues. They have been shown to be strong antioxidants, and may exert a wide range of health benefits through antioxidant or other mechanisms. Anthocyanins occur primarily as g...

  1. Wanted: Information on the Distribution of Cultivated Plants

    ERIC Educational Resources Information Center

    Howard, Richard A.

    1970-01-01

    Lack of documentation makes it very difficult to discover where species of cultivated plants may be found in the United States. Plead for compilation of "campus floras and herbarium collections. Need for a rational locator file of available plant materials. Lists and reviews present sources of information. Bibliography of campus floras. (EB)

  2. Phylogenetic analysis of a gene cluster encoding an additional, rhizobial-like type III secretion system that is narrowly distributed among Pseudomonas syringae strains

    PubMed Central

    2012-01-01

    Background The central role of Type III secretion systems (T3SS) in bacteria-plant interactions is well established, yet unexpected findings are being uncovered through bacterial genome sequencing. Some Pseudomonas syringae strains possess an uncharacterized cluster of genes encoding putative components of a second T3SS (T3SS-2) in addition to the well characterized Hrc1 T3SS which is associated with disease lesions in host plants and with the triggering of hypersensitive response in non-host plants. The aim of this study is to perform an in silico analysis of T3SS-2, and to compare it with other known T3SSs. Results Based on phylogenetic analysis and gene organization comparisons, the T3SS-2 cluster of the P. syringae pv. phaseolicola strain is grouped with a second T3SS found in the pNGR234b plasmid of Rhizobium sp. These additional T3SS gene clusters define a subgroup within the Rhizobium T3SS family. Although, T3SS-2 is not distributed as widely as the Hrc1 T3SS in P. syringae strains, it was found to be constitutively expressed in P. syringae pv phaseolicola through RT-PCR experiments. Conclusions The relatedness of the P. syringae T3SS-2 to a second T3SS from the pNGR234b plasmid of Rhizobium sp., member of subgroup II of the rhizobial T3SS family, indicates common ancestry and/or possible horizontal transfer events between these species. Functional analysis and genome sequencing of more rhizobia and P. syringae pathovars may shed light into why these bacteria maintain a second T3SS gene cluster in their genome. PMID:22937899

  3. Biochemical characterization of a recombinant plant class III chitinase from the pitcher of the carnivorous plant Nepenthes alata.

    PubMed

    Ishisaki, Kana; Arai, Sachiko; Hamada, Tatsuro; Honda, Yuji

    2012-11-01

    A class III chitinase belonging to the GH18 family from Nepenthes alata (NaCHIT3) was expressed in Escherichia coli. The enzyme exhibited hydrolytic activity toward colloidal chitin, ethylene glycol chitin, and (GlcNAc)(n) (n=5 and 6). The enzyme hydrolyzed the fourth glycosidic linkage from the non-reducing end of (GlcNAc)(6). The anomeric form of the products indicated it was a retaining enzyme. The colloidal chitin hydrolytic reaction displayed high activity between pH 3.9 and 6.9, but the pH optimum of the (GlcNAc)(6) hydrolytic reaction was 3.9 at 37 °C. The optimal temperature for activity was 65 °C in 50 mM sodium acetate buffer (pH 3.9). The pH optima of NaCHIT3 and NaCHIT1 might be related to their roles in chitin degradation in the pitcher fluid.

  4. Financial Report of Ontario Universities 1990-91, Volume III: Physical Plant Operating Expenses.

    ERIC Educational Resources Information Center

    Council of Ontario Universities, Toronto.

    This report provides an analysis of the physical plant costs, by major functional area and object of expense, as reported in the operating fund of each university in Ontario, Canada. The report begins with a brief introduction; a description of the principles governing the reporting process; and definitions and explanatory comment on the physical…

  5. Financial Report of Ontario Universities 1991-92, Volume III-Physical Plant Operating Expenses.

    ERIC Educational Resources Information Center

    Council of Ontario Universities, Toronto.

    This report provides an analysis of the physical plant costs, by major functional area and object of expense, as reported in the operating fund of each university in Ontario, Canada. The report begins with a brief introduction; a description of the principles governing the reporting process; and definitions and explanatory comment on the physical…

  6. Abscisic acid and other plant hormones: Methods to visualize distribution and signaling.

    PubMed

    Waadt, Rainer; Hsu, Po-Kai; Schroeder, Julian I

    2015-12-01

    The exploration of plant behavior on a cellular scale in a minimal invasive manner is key to understanding plant adaptations to their environment. Plant hormones regulate multiple aspects of growth and development and mediate environmental responses to ensure a successful life cycle. To monitor the dynamics of plant hormone actions in intact tissue, we need qualitative and quantitative tools with high temporal and spatial resolution. Here, we describe a set of biological instruments (reporters) for the analysis of the distribution and signaling of various plant hormones. Furthermore, we provide examples of their utility for gaining novel insights into plant hormone action with a deeper focus on the drought hormone abscisic acid.

  7. Abscisic acid and other plant hormones: Methods to visualize distribution and signaling

    PubMed Central

    Waadt, Rainer; Hsu, Po-Kai; Schroeder, Julian I.

    2015-01-01

    The exploration of plant behavior on a cellular scale in a minimal invasive manner is key to understanding plant adaptations to their environment. Plant hormones regulate multiple aspects of growth and development and mediate environmental responses to ensure a successful life cycle. To monitor the dynamics of plant hormone actions in intact tissue, we need qualitative and quantitative tools with high temporal and spatial resolution. Here, we describe a set of biological instruments (reporters) for the analysis of the distribution and signaling of various plant hormones. Furthermore, we provide examples of their utility for gaining novel insights into plant hormone action with a deeper focus on the drought hormone abscisic acid. PMID:26577078

  8. Abscisic acid and other plant hormones: Methods to visualize distribution and signaling.

    PubMed

    Waadt, Rainer; Hsu, Po-Kai; Schroeder, Julian I

    2015-12-01

    The exploration of plant behavior on a cellular scale in a minimal invasive manner is key to understanding plant adaptations to their environment. Plant hormones regulate multiple aspects of growth and development and mediate environmental responses to ensure a successful life cycle. To monitor the dynamics of plant hormone actions in intact tissue, we need qualitative and quantitative tools with high temporal and spatial resolution. Here, we describe a set of biological instruments (reporters) for the analysis of the distribution and signaling of various plant hormones. Furthermore, we provide examples of their utility for gaining novel insights into plant hormone action with a deeper focus on the drought hormone abscisic acid. PMID:26577078

  9. Plant targets for Pseudomonas syringae type III effectors: virulence targets or guarded decoys?

    PubMed

    Block, Anna; Alfano, James R

    2011-02-01

    The phytopathogenic bacterium Pseudomonas syringae can suppress both pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) by the injection of type III effector (T3E) proteins into host cells. T3Es achieve immune suppression using a variety of strategies including interference with immune receptor signaling, blocking RNA pathways and vesicle trafficking, and altering organelle function. T3Es can be recognized indirectly by resistance proteins monitoring specific T3E targets resulting in ETI. It is presently unclear whether the monitored targets represent bona fide virulence targets or guarded decoys. Extensive overlap between PTI and ETI signaling suggests that T3Es may suppress both pathways through common targets and by possessing multiple activities. PMID:21227738

  10. Within-plant distribution of onion thrips (Thysanoptera: Thripidae) in onions.

    PubMed

    Mo, Jianhua; Munro, Scott; Boulton, Alan; Stevens, Mark

    2008-08-01

    Two aspects of the within-plant distribution of Thrips tabaci Lindeman (Thysanoptera: Thripidae) on onion, Allium cepa L., plants were investigated: 1) diurnal variations in the distribution of adults and larvae between basal and upper sections of onion leaves, and 2) between-leaf and within-leaf distribution of the eggs. The diurnal investigations showed that higher proportions of larvae than of adults congregated at the basal sections of plants, particularly when plants were young and thrips density was low. As plants matured and thrips density increased, the larvae became more dispersed. Regardless of plant size, there were always more adults in the upper than basal plant sections. There were no clear time-windows during the 24-h diurnal cycle when more thrips were in the upper plant parts. T. tabaci eggs were laid everywhere in the plant. Leaves of intermediate ages had more eggs than older or younger leaves. Within leaves, the white leaf sheath received the least eggs and leaf tips received slightly more eggs than leaf sheaths. The highest egg density was found between the green leaf base and the leaf tips. Regardless of plant size, more than half of all eggs were laid above the basal sections. The percentage increased to >95% in mature plants. Except when plants were small the outer leaves were preferred over inner leaves and upper leaf sections preferred over lower leaf sections as egg-laying sites by adults. Implications of the results in the management of T. tabaci are discussed.

  11. Within-plant distribution of onion thrips (Thysanoptera: Thripidae) in onions.

    PubMed

    Mo, Jianhua; Munro, Scott; Boulton, Alan; Stevens, Mark

    2008-08-01

    Two aspects of the within-plant distribution of Thrips tabaci Lindeman (Thysanoptera: Thripidae) on onion, Allium cepa L., plants were investigated: 1) diurnal variations in the distribution of adults and larvae between basal and upper sections of onion leaves, and 2) between-leaf and within-leaf distribution of the eggs. The diurnal investigations showed that higher proportions of larvae than of adults congregated at the basal sections of plants, particularly when plants were young and thrips density was low. As plants matured and thrips density increased, the larvae became more dispersed. Regardless of plant size, there were always more adults in the upper than basal plant sections. There were no clear time-windows during the 24-h diurnal cycle when more thrips were in the upper plant parts. T. tabaci eggs were laid everywhere in the plant. Leaves of intermediate ages had more eggs than older or younger leaves. Within leaves, the white leaf sheath received the least eggs and leaf tips received slightly more eggs than leaf sheaths. The highest egg density was found between the green leaf base and the leaf tips. Regardless of plant size, more than half of all eggs were laid above the basal sections. The percentage increased to >95% in mature plants. Except when plants were small the outer leaves were preferred over inner leaves and upper leaf sections preferred over lower leaf sections as egg-laying sites by adults. Implications of the results in the management of T. tabaci are discussed. PMID:18767744

  12. On the Distribution of Free Path Lengths for the Periodic Lorentz Gas III

    NASA Astrophysics Data System (ADS)

    Caglioti, Emanuele; Golse, François

    For r(0,1), let Zr={xR2|dist(x,Z2)>r/2} and define τr(x,v)=inf{t>0|x+tv∂Zr}. Let Φr(t) be the probability that τr(x,v)>=t for x and v uniformly distributed in Zr and §1 respectively. We prove in this paper that as t-->+∞. This result improves upon the bounds on Φr in Bourgain-Golse-Wennberg [Commun. Math. Phys. 190, 491-508 (1998)]. We also discuss the applications of this result in the context of kinetic theory.

  13. Community-Weighted Mean Plant Traits Predict Small Scale Distribution of Insect Root Herbivore Abundance.

    PubMed

    Sonnemann, Ilja; Pfestorf, Hans; Jeltsch, Florian; Wurst, Susanne

    2015-01-01

    Small scale distribution of insect root herbivores may promote plant species diversity by creating patches of different herbivore pressure. However, determinants of small scale distribution of insect root herbivores, and impact of land use intensity on their small scale distribution are largely unknown. We sampled insect root herbivores and measured vegetation parameters and soil water content along transects in grasslands of different management intensity in three regions in Germany. We calculated community-weighted mean plant traits to test whether the functional plant community composition determines the small scale distribution of insect root herbivores. To analyze spatial patterns in plant species and trait composition and insect root herbivore abundance we computed Mantel correlograms. Insect root herbivores mainly comprised click beetle (Coleoptera, Elateridae) larvae (43%) in the investigated grasslands. Total insect root herbivore numbers were positively related to community-weighted mean traits indicating high plant growth rates and biomass (specific leaf area, reproductive- and vegetative plant height), and negatively related to plant traits indicating poor tissue quality (leaf C/N ratio). Generalist Elaterid larvae, when analyzed independently, were also positively related to high plant growth rates and furthermore to root dry mass, but were not related to tissue quality. Insect root herbivore numbers were not related to plant cover, plant species richness and soil water content. Plant species composition and to a lesser extent plant trait composition displayed spatial autocorrelation, which was not influenced by land use intensity. Insect root herbivore abundance was not spatially autocorrelated. We conclude that in semi-natural grasslands with a high share of generalist insect root herbivores, insect root herbivores affiliate with large, fast growing plants, presumably because of availability of high quantities of food. Affiliation of insect root

  14. Community- Weighted Mean Plant Traits Predict Small Scale Distribution of Insect Root Herbivore Abundance

    PubMed Central

    Jeltsch, Florian; Wurst, Susanne

    2015-01-01

    Small scale distribution of insect root herbivores may promote plant species diversity by creating patches of different herbivore pressure. However, determinants of small scale distribution of insect root herbivores, and impact of land use intensity on their small scale distribution are largely unknown. We sampled insect root herbivores and measured vegetation parameters and soil water content along transects in grasslands of different management intensity in three regions in Germany. We calculated community-weighted mean plant traits to test whether the functional plant community composition determines the small scale distribution of insect root herbivores. To analyze spatial patterns in plant species and trait composition and insect root herbivore abundance we computed Mantel correlograms. Insect root herbivores mainly comprised click beetle (Coleoptera, Elateridae) larvae (43%) in the investigated grasslands. Total insect root herbivore numbers were positively related to community-weighted mean traits indicating high plant growth rates and biomass (specific leaf area, reproductive- and vegetative plant height), and negatively related to plant traits indicating poor tissue quality (leaf C/N ratio). Generalist Elaterid larvae, when analyzed independently, were also positively related to high plant growth rates and furthermore to root dry mass, but were not related to tissue quality. Insect root herbivore numbers were not related to plant cover, plant species richness and soil water content. Plant species composition and to a lesser extent plant trait composition displayed spatial autocorrelation, which was not influenced by land use intensity. Insect root herbivore abundance was not spatially autocorrelated. We conclude that in semi-natural grasslands with a high share of generalist insect root herbivores, insect root herbivores affiliate with large, fast growing plants, presumably because of availability of high quantities of food. Affiliation of insect root

  15. The Pressure Distribution over the Horizontal Tail Surfaces of an Airplane III

    NASA Technical Reports Server (NTRS)

    Norton, F H; Brown, W G

    1923-01-01

    This report contains the results of an investigation of the distribution of pressure over the tail surfaces of a full-sized airplane during accelerated flight for the purpose of determining the magnitude of the tail and fuselage stresses in maneuvering. As the pressures in accelerated flight change in value with great rapidity, it was found that the liquid manometer used in the first part of this investigation would not be at all suitable under these conditions; so it was necessary to design and construct a new manometer containing a large number of recording diaphragm gauges for these measurements. Sixty openings on the tail surfaces were connected to this manometer and continuous records of pressures for each pair of holes were taken during various maneuvers. There were also recorded, simultaneously with the pressures, the normal acceleration at the center of gravity and the angular position of all the controls. The present investigation consisted in measuring on a standard rigged JN4H airplane the distribution of pressure over the whole of the horizontal tail surfaces while the airplane was being put through maneuvers as violently as it was thought safe, including spinning and pulling out of dives.

  16. An evaluation of earthquake hazard parameters in the Iranian Plateau based on the Gumbel III distribution

    NASA Astrophysics Data System (ADS)

    Mohammadi, Hiwa; Bayrak, Yusuf

    2016-04-01

    The Gumbel's third asymptotic distribution (GIII) of the extreme value method is employed to evaluate the earthquake hazard parameters in the Iranian Plateau. This research quantifies spatial mapping of earthquake hazard parameters like annual and 100-year mode beside their 90 % probability of not being exceeded (NBE) in the Iranian Plateau. Therefore, we used a homogeneous and complete earthquake catalogue during the period 1900-2013 with magnitude M w ≥ 4.0, and the Iranian Plateau is separated into equal area mesh of 1° late × 1° long. The estimated result of annual mode with 90 % probability of NBE is expected to exceed the values of M w 6.0 in the Eastern part of Makran, most parts of Central and East Iran, Kopeh Dagh, Alborz, Azerbaijan, and SE Zagros. The 100-year mode with 90 % probability of NBE is expected to overpass the value of M w 7.0 in the Eastern part of Makran, Central and East Iran, Alborz, Kopeh Dagh, and Azerbaijan. The spatial distribution of 100-year mode with 90 % probability of NBE uncovers the high values of earthquake hazard parameters which are frequently connected with the main tectonic regimes of the studied area. It appears that there is a close communication among the seismicity and the tectonics of the region.

  17. Industrial Fuel Gas Demonstration Plant Program. Task III, Demonstration plant safety, industrial hygiene, and major disaster plan (Deliverable No. 35)

    SciTech Connect

    1980-03-01

    This Health and Safety Plan has been adopted by the IFG Demonstration Plant managed by Memphis Light, Gas and Water at Memphis, Tennessee. The plan encompasses the following areas of concern: Safety Plan Administration, Industrial Health, Industrial Safety, First Aid, Fire Protection (including fire prevention and control), and Control of Safety Related Losses. The primary objective of this plan is to achieve adequate control of all potentially hazardous activities to assure the health and safety of all employees and eliminate lost work time to both the employees and the company. The second objective is to achieve compliance with all Federal, state and local laws, regulations and codes. Some thirty specific safe practice instruction items are included.

  18. [Molecular aspects of allergy to plant products. Part III. Panallergens and breeding of hypoallergenic cultivars].

    PubMed

    Bokszczanin, Kamila Ł; Przybyła, Andrzej A

    2012-04-01

    In addition to major allergens, also minor allergens, i.e. panallergens have been shown to be responsible for many IgE cross-reactions even between unrelated pollen and plant food allergen sources. It can be explained also by cross-allergenicity underlying the T cell response to conserved regions of panallergens. In this article, we focus on known panallergens which presently comprise a few protein families, including non-specific lipid transfer proteins (nsLTP) (PR-14), thaumatin like proteins (TLP) (PR-5), profilins, and polcalcins. Food allergy has an impact on the quality of life of an allergic patient. The way of developing novel plant cultivars with decreased allergenicity and possibility of down-regulating the expression of an allergen by genetic modification are discussed.

  19. Energy Distribution among Reaction Products. III: The Method of Measured Relaxation Applied to H + Cl2

    NASA Technical Reports Server (NTRS)

    Pacey, P. D.; Polyani, J. C.

    1971-01-01

    The method of measured relaxation is described for the determination of initial vibrational energy distribution in the products of exothermic reaction. Hydrogen atoms coming from an orifice were diffused into flowing chlorine gas. Measurements were made of the resultant ir chemiluminescence at successive points along the line of flow. The concurrent processes of reaction, diffusion, flow, radiation, and deactivation were analyzed in some detail on a computer. A variety of relaxation models were used in an attempt to place limits on k(nu prime), the rate constant for reaction to form HCl in specified vibrational energy levels: H+Cl2 yields (sup K(nu prime) HCl(sub nu prime) + Cl. The set of k(?) obtained from this work is in satisfactory agreement with those obtained by another experimental method (the method of arrested relaxation described in Parts IV and V of the present series.

  20. Jamaica Bay studies III: Abiotic determinants of distribution and abundance of gulls ( Larus)

    NASA Astrophysics Data System (ADS)

    Burger, Joanna

    1983-02-01

    The distribution and abundance of gulls were examined at Jamaica Bay Wildlife Refuge (New York) from 31 May 1978 to 31 May 1979. Gulls were found to be affected by tidal, temporal and weather-related factors. The distribution of gulls was affected primarily by tidal factors on the bay, and by temporal (seasonal, circadian) and weather-related factors on the freshwater ponds. The most important weather-related factors were temperature, wind velocity and wind direction. Herring ( L. argentatus), great black-backed ( L. fuscus) and ring-billed gulls ( L. delawarensis) fed on the bay at low tides, and used the ponds at high tide. Laughing gulls ( L. atricilla) fed on the bay at low tide and on rising tides. Herring and great black-backed gulls were present all year, but were most abundant in the winter, ring-billed gulls were abundant in spring and early fall, and laughing gulls were present in the summer following the breeding season but were absent in winter. Gulls used the ponds during high velocity, north winds, when they usually rested or preened. Multiple regression models were used to determine the factors explaining the variability in the numbers of gulls. Temporal variables were important contributors to accounting for the variability in the numbers of great black-backed and herring gulls only; tidal variables were significant for great black-backed and herring gulls on the bay, and for ring-billed and laughing gulls on all areas; and weather variables were significant for all species.

  1. Within-plant distribution of Aulacorthum solani (Hemiptera: Aphididae), on various greenhouse plants with implications for control.

    PubMed

    Jandricic, S E; Mattson, N S; Wraight, S P; Sanderson, J P

    2014-04-01

    Foxglove aphid, Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae), has recently undergone a status change from an occasional pest to a serious pest in greenhouses of North America and the United Kingdom. Little nonanecdotal information exists on the ecology of this insect in greenhouse crops. To help improve integrated pest management decisions for A. solani, the within-plant distribution of this pest was explored on a variety of common greenhouse plants in both the vegetative and flowering stage. This aphid generally was found on lower leaves of vegetative plants, but was found higher in the canopy on reproductive plants (on flowers, flower buds, or upper leaves). Aphid numbers were not consistently positively correlated with total leaf surface areas within plant strata across plant species. Thus, the observed differences in preferred feeding sites on vegetative versus flowering plants are possibly a response to differences in nutritional quality of the various host-plant tissues. Despite being anecdotally described as a "stem-feeding aphid," A. solani was rarely found feeding on stems at the population densities established in our tests, with the exception of racemes of scarlet sage (Salvia splendans). Although some previous reports suggested that A. solani prefers to feed on new growth of plants, our results indicate that mature leaves are preferred over growing tips and young leaves. The implications of the within-plant feeding preferences of A. solani populations with respect to both biological and chemical control are discussed.

  2. Multi-component Erlang distribution of plant seed masses and sizes

    NASA Astrophysics Data System (ADS)

    Fan, San-Hong; Wei, Hua-Rong

    2012-12-01

    The mass and the size distributions of plant seeds are very similar to the multi-component Erlang distribution of final-state particle multiplicities in high-energy collisions. We study the mass, length, width, and thickness distributions of pumpkin and marrow squash seeds in this paper. The corresponding distribution curves are obtained and fitted by using the multi-component Erlang distribution. In the comparison, the method of χ2-testing is used. The mass and the size distributions of the mentioned seeds are shown to obey approximately the multi-component Erlang distribution with the component number being 1.

  3. Plant growth and metal distribution in tissues of Prosopis juliflora-velutina grown on chromium contaminated soil in the presence of Glomus deserticola.

    PubMed

    Arias, Jack A; Peralta-Videa, Jose R; Ellzey, Joanne T; Viveros, Marian N; Ren, Minghua; Mokgalaka-Matlala, Ntebogeng S; Castillo-Michel, Hiram; Gardea-Torresdey, Jorge L

    2010-10-01

    Arbuscular mycorrhizal fungi have been known to increase metal uptake in plants. In this study, mesquite (Prosopis juliflora-velutina) inoculated with Glomus deserticola or amended with EDTA were grown for 30 days in soil containing Cr(III) or Cr(VI) at 0, 40, 80, and 160 mg kg(-1). Total amylase activity (TAA) was monitored as a stress indicator. Element concentrations and distribution in tissue were determined using ICP-OES, electron scanning microprobe, and TEM. Inoculated Cr(VI) treated plants had 21% and 30% more Cr than uninoculated and EDTA treated roots, respectively, at 80 mg Cr kg(-1) treatment. In the case of Cr(III), EDTA produced the highest Cr accumulation in roots. TAA was higher in inoculated plants grown with Cr(III) at 80 and 160 mg kg(-1) and Cr(VI) at 40 and 160 mg kg(-1). The X-ray mapping showed higher metal concentrations in the vascular system of inoculated plants and the TEM micrographs demonstrated the presence of G. deserticola in roots.

  4. ASSESSMENT OF SUBSURFACE FATE OF MONOETHANOLAMINE AT SOUR GAS PROCESSING PLANT SITES-PHASE III

    SciTech Connect

    James A. Sorensen

    1999-02-01

    Alkanolamines are commonly used by the natural gas industry to remove hydrogen sulfide, carbon dioxide, and other acid gases from the natural gas in which they occur (''sour'' gas if hydrogen sulfide is present). At sour gas-processing plants, as at all plants that use alkanolamines for acid gas removal (AGR), spills and on-site management of wastes containing alkanolamines and associated reaction products have occasionally resulted in subsurface contamination that is presently the focus of some environmental concern. In 1994, the Energy and Environmental Research Center (EERC) initiated a three-phase program to investigate the natural attenuation processes that control the subsurface transport and fate of the most commonly used alkanolamine in Canada, monoethanolamine (MEA). Funding for the MEA research program was provided by the U.S. Department of Energy (DOE), Canadian Association of Petroleum Producers (CAPP), Canadian Occidental Petroleum Ltd. (CanOxy), Gas Research Institute (GRI), Environment Canada, and the National Energy Board of Canada. The MEA research program focused primarily on examining the biodegradability of MEA and MEA-related waste materials in soils and soil-slurries under a variety of environmentally relevant conditions, evaluating the mobility of MEA in soil and groundwater and the effectiveness of bioremediation techniques for removing contaminants and toxicity from MEA-contaminated soil. The presently inactive Okotoks sour gas-processing plant, owned by CanOxy in Alberta, Canada, was the source of samples and field data for much of the laboratory-based experimental work and was selected to be the location for the field-based efforts to evaluate remediation techniques. The objective of the research program is to provide the natural gas industry with ''real world'' data and insights developed under laboratory and field conditions regarding the effective and environmentally sound use of biological methods for the remediation of soil

  5. Understanding star formation in molecular clouds. III. Probability distribution functions of molecular lines in Cygnus X

    NASA Astrophysics Data System (ADS)

    Schneider, N.; Bontemps, S.; Motte, F.; Ossenkopf, V.; Klessen, R. S.; Simon, R.; Fechtenbaum, S.; Herpin, F.; Tremblin, P.; Csengeri, T.; Myers, P. C.; Hill, T.; Cunningham, M.; Federrath, C.

    2016-03-01

    The probability distribution function of column density (N-PDF) serves as a powerful tool to characterise the various physical processes that influence the structure of molecular clouds. Studies that use extinction maps or H2 column-density maps (N) that are derived from dust show that star-forming clouds can best be characterised by lognormal PDFs for the lower N range and a power-law tail for higher N, which is commonly attributed to turbulence and self-gravity and/or pressure, respectively. While PDFs from dust cover a large dynamic range (typically N ~ 1020-24 cm-2 or Av~ 0.1-1000), PDFs obtained from molecular lines - converted into H2 column density - potentially trace more selectively different regimes of (column) densities and temperatures. They also enable us to distinguish different clouds along the line of sight through using the velocity information. We report here on PDFs that were obtained from observations of 12CO, 13CO, C18O, CS, and N2H+ in the Cygnus X North region, and make a comparison to a PDF that was derived from dust observations with the Herschel satellite. The PDF of 12CO is lognormal for Av ~ 1-30, but is cut for higher Av because of optical depth effects. The PDFs of C18O and 13CO are mostly lognormal up to Av ~ 1-15, followed by excess up to Av ~ 40. Above that value, all CO PDFs drop, which is most likely due to depletion. The high density tracers CS and N2H+ exhibit only a power law distribution between Av ~ 15 and 400, respectively. The PDF from dust is lognormal for Av ~ 3-15 and has a power-law tail up to Av ~ 500. Absolute values for the molecular line column densities are, however, rather uncertain because of abundance and excitation temperature variations. If we take the dust PDF at face value, we "calibrate" the molecular line PDF of CS to that of the dust and determine an abundance [CS]/[H2] of 10-9. The slopes of the power-law tails of the CS, N2H+, and dust PDFs are -1.6, -1.4, and -2.3, respectively, and are thus consistent

  6. High reflectivity III-nitride UV-C distributed Bragg reflectors for vertical cavity emitting lasers

    NASA Astrophysics Data System (ADS)

    Franke, A.; Hoffmann, M. P.; Kirste, R.; Bobea, M.; Tweedie, J.; Kaess, F.; Gerhold, M.; Collazo, R.; Sitar, Z.

    2016-10-01

    UV-C distributed Bragg reflectors (DBRs) for vertical cavity surface emitting laser applications and polariton lasers are presented. The structural integrity of up to 25 layer pairs of AlN/Al0.65Ga0.35N DBRs is maintained by balancing the tensile and compressive strain present between the single layers of the multilayer stack grown on top of an Al0.85Ga0.35N template. By comparing the structural and optical properties for DBRs grown on low dislocation density AlN and AlGaN templates, the criteria for plastic relaxation by cracking thick nitride Bragg reflectors are deduced. The critical thickness is found to be limited mainly by the accumulated strain energy during the DBR growth and is only negligibly affected by the dislocations. A reflectance of 97.7% at 273 nm is demonstrated. The demonstrated optical quality and an ability to tune the resonance wavelength of our resonators and microcavity structures open new opportunities for UV-C vertical emitters.

  7. Functional characterization of a class III acid endochitinase from the traps of the carnivorous pitcher plant genus, Nepenthes.

    PubMed

    Rottloff, Sandy; Stieber, Regina; Maischak, Heiko; Turini, Florian G; Heubl, Günther; Mithöfer, Axel

    2011-08-01

    Carnivory in plants is an adaptation strategy to nutrient-poor environments and soils. Carnivorous plants obtain some additional mineral nutrients by trapping and digesting prey; the genus Nepenthes is helped by its specialized pitcher traps. To make the nutrients available, the caught prey needs to be digested, a process that requires the concerted activity of several hydrolytic enzymes. To identify and investigate the various enzymes involved in this process, fluid from Nepenthes traps has been analysed in detail. In this study, a novel type of Nepenthes endochitinase was identified in the digestion fluid of closed pitchers. The encoding endochitinase genes have been cloned from eight different Nepenthes species. Among these, the deduced amino acid sequence similarity was at least 94.9%. The corresponding cDNA from N. rafflesiana was heterologously expressed, and the purified protein, NrChit1, was biochemically characterized. The enzyme, classified as a class III acid endochitinase belonging to family 18 of the glycoside hydrolases, is secreted into the pitcher fluid very probably due to the presence of an N-terminal signal peptide. Transcriptome analyses using real-time PCR indicated that the presence of prey in the pitcher up-regulates the endochitinase gene not only in the glands, which are responsible for enzyme secretion, but at an even higher level, in the glands' surrounding tissue. These results suggest that in the pitchers' tissues, the endochitinase as well as other proteins from the pitcher fluid might fulfil a different, primary function as pathogenesis-related proteins.

  8. Membrane topology of conserved components of the type III secretion system from the plant pathogen Xanthomonas campestris pv. vesicatoria.

    PubMed

    Berger, Carolin; Robin, Guillaume P; Bonas, Ulla; Koebnik, Ralf

    2010-07-01

    Type III secretion (T3S) systems play key roles in the assembly of flagella and the translocation of bacterial effector proteins into eukaryotic host cells. Eleven proteins which are conserved among gram-negative plant and animal pathogenic bacteria have been proposed to build up the basal structure of the T3S system, which spans both inner and outer bacterial membranes. We studied six conserved proteins, termed Hrc, predicted to reside in the inner membrane of the plant pathogen Xanthomonas campestris pv. vesicatoria. The membrane topology of HrcD, HrcR, HrcS, HrcT, HrcU and HrcV was studied by translational fusions to a dual alkaline phosphatase-beta-galactosidase reporter protein. Two proteins, HrcU and HrcV, were found to have the same membrane topology as the Yersinia homologues YscU and YscV. For HrcR, the membrane topology differed from the model for the homologue from Yersinia, YscR. For our data on three other protein families, exemplified by HrcD, HrcS and HrcT, we derived the first topology models. Our results provide what is believed to be the first complete model of the inner membrane topology of any bacterial T3S system and will aid in elucidating the architecture of T3S systems by ultrastructural analysis. PMID:20378646

  9. Metal binding properties and structure of a type III metallothionein from the metal hyperaccumulator plant Noccaea caerulescens.

    PubMed

    Fernandez, Lucia Rubio; Vandenbussche, Guy; Roosens, Nancy; Govaerts, Cédric; Goormaghtigh, Erik; Verbruggen, Nathalie

    2012-09-01

    Metallothioneins (MT) are low molecular weight proteins with cysteine-rich sequences that bind heavy metals with remarkably high affinities. Plant MTs differ from animal ones by a peculiar amino acid sequence organization consisting of two short Cys-rich terminal domains (containing from 4 to 8 Cys each) linked by a Cys free region of about 30 residues. In contrast with the current knowledge on the 3D structure of animal MTs, there is a striking lack of structural data on plant MTs. We have expressed and purified a type III MT from Noccaea caerulescens (previously Thlaspi caerulescens). This protein is able to bind a variety of cations including Cd(2+), Cu(2+), Zn(2+) and Pb(2+), with different stoichiometries as shown by mass spectrometry. The protein displays a complete absence of periodic secondary structures as measured by far-UV circular dichroism, infrared spectroscopy and hydrogen/deuterium exchange kinetics. When attached onto a BIA-ATR biosensor, no significant structural change was observed upon removing the metal ions. PMID:22668884

  10. Distribution function approach to redshift space distortions. Part III: halos and galaxies

    SciTech Connect

    Okumura, Teppei; Seljak, Uroš; Desjacques, Vincent E-mail: useljak@berkeley.edu

    2012-11-01

    It was recently shown that the power spectrum in redshift space can be written as a sum of cross-power spectra between number weighted velocity moments, of which the lowest are density and momentum density. We investigate numerically the properties of these power spectra for simulated galaxies and dark matter halos and compare them to the dark matter power spectra, generalizing the concept of the bias in density-density power spectra. Because all of the quantities are number weighted this approach is well defined even for sparse systems such as massive halos. This contrasts to the previous approaches to RSD where velocity correlations have been explored, but velocity field is a poorly defined concept for sparse systems. We find that the number density weighting leads to a strong scale dependence of the bias terms for momentum density auto-correlation and cross-correlation with density. This trend becomes more significant for the more biased halos and leads to an enhancement of RSD power relative to the linear theory. Fingers-of-god effects, which in this formalism come from the correlations of the higher order moments beyond the momentum density, lead to smoothing of the power spectrum and can reduce this enhancement of power from the scale dependent bias, but are relatively small for halos with no small scale velocity dispersion. In comparison, for a more realistic galaxy sample with satellites the small scale velocity dispersion generated by satellite motions inside the halos leads to a larger power suppression on small scales, but this depends on the satellite fraction and on the details of how the satellites are distributed inside the halo. We investigate several statistics such as the two-dimensional power spectrum P(k,μ), where μ is the angle between the Fourier mode and line of sight, its multipole moments, its powers of μ{sup 2}, and configuration space statistics. Overall we find that the nonlinear effects in realistic galaxy samples such as luminous

  11. Turbulence-induced relative velocity of dust particles. III. The probability distribution

    SciTech Connect

    Pan, Liubin; Padoan, Paolo; Scalo, John E-mail: ppadoan@icc.ub.edu

    2014-09-01

    Motivated by its important role in the collisional growth of dust particles in protoplanetary disks, we investigate the probability distribution function (PDF) of the relative velocity of inertial particles suspended in turbulent flows. Using the simulation from our previous work, we compute the relative velocity PDF as a function of the friction timescales, τ{sub p1} and τ{sub p2}, of two particles of arbitrary sizes. The friction time of the particles included in the simulation ranges from 0.1τ{sub η} to 54T {sub L}, where τ{sub η} and T {sub L} are the Kolmogorov time and the Lagrangian correlation time of the flow, respectively. The relative velocity PDF is generically non-Gaussian, exhibiting fat tails. For a fixed value of τ{sub p1}, the PDF shape is the fattest for equal-size particles (τ{sub p2} = τ{sub p1}), and becomes thinner at both τ{sub p2} < τ{sub p1} and τ{sub p2} > τ{sub p1}. Defining f as the friction time ratio of the smaller particle to the larger one, we find that, at a given f in (1/2) ≲ f ≲ 1, the PDF fatness first increases with the friction time τ{sub p,h} of the larger particle, peaks at τ{sub p,h} ≅ τ{sub η}, and then decreases as τ{sub p,h} increases further. For 0 ≤ f ≲ (1/4), the PDF becomes continuously thinner with increasing τ{sub p,h}. The PDF is nearly Gaussian only if τ{sub p,h} is sufficiently large (>>T {sub L}). These features are successfully explained by the Pan and Padoan model. Using our simulation data and some simplifying assumptions, we estimated the fractions of collisions resulting in sticking, bouncing, and fragmentation as a function of the dust size in protoplanetary disks, and argued that accounting for non-Gaussianity of the collision velocity may help further alleviate the bouncing barrier problem.

  12. Spatial distribution of plant-parasitic nematodes in semi-arid Vitis vinifera vineyards in Washington

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards are Meloidogyne hapla, Mesocriconema xenoplax, Pratylenchus spp., Xiphinema americanum, and Paratylenchus sp.; however, little is known about their distribution in the soil profile. The vertical an...

  13. New host plant and distribution records for Peruvian Tephritinae (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Distribution and host plant records (all Asteraceae) are reported for 17 species of Tephritinae: Acinia reticulata (stem galls on Tessaria integrifolia); Dracontomyia footei (Baccharis salicifolia); Ensina hyalipennis (Argentina; flowerheads of Sonchus asper); E. longiceps (flowerheads of Hypochaeri...

  14. Pollution tolerance and distribution pattern of plants in surrounding area of coal-fired industries.

    PubMed

    Dwivedi, A K; Tripathi, B D

    2007-04-01

    Higher concentration of SO2 and particulate matters was reported in surrounding areas of coal-fired industries which influences the distribution pattern of plants. Sensitive plant species are abolished from such areas, however, only pollution tolerant species survive under stress conditions. The present study was designed to investigate the vegetation composition around coal-fired industries i.e. brick industries. To categorise plants as sensitive or resistant air pollution tolerance index (APTI) value was calculated. Out of 99 plants studied, Ricinus communis with APTI 81.10 was found to be the most resistant wild plant showing uniform distribution at all the polluted sites. On the other hand, Lepidium sativum with APTI 5.27 was recorded as the most sensitive plant and found to be present only at the less polluted sites.

  15. Integration of distributed plant process computer systems to nuclear power generation facilities

    SciTech Connect

    Bogard, T.; Finlay, K.

    1996-11-01

    Many operating nuclear power generation facilities are replacing their plant process computer. Such replacement projects are driven by equipment obsolescence issues and associated objectives to improve plant operability, increase plant information access, improve man machine interface characteristics, and reduce operation and maintenance costs. This paper describes a few recently completed and on-going replacement projects with emphasis upon the application integrated distributed plant process computer systems. By presenting a few recent projects, the variations of distributed systems design show how various configurations can address needs for flexibility, open architecture, and integration of technological advancements in instrumentation and control technology. Architectural considerations for optimal integration of the plant process computer and plant process instrumentation & control are evident from variations of design features.

  16. Content and distribution of flavonoids among 91 edible plant species.

    PubMed

    Yang, Ray-Yu; Lin, Shou; Kuo, George

    2008-01-01

    Flavonoid contents as aglycones (for quercetin, kaempherol, isorhamnetin, luteolin and apigenin) were reported for 115 edible plants (91 species). Plant materials mostly originated in tropical zones were grown and harvested from AVRDC, Taiwan. Acid extraction and HPLC were used as analytical methods. Total flavonoid contents ranged from 0 to 254 mg/100g fresh weight. About 75% of samples were found to contain flavonoids > 0.5 mg/100g with the group mean 33 +/- 48 mg/100g. Data for only 30 samples (20 species) in this study are also available (measured as raw vegetables) in the USDA flavonoid database. This study can expand the flavonoid database and contribute to measurement of flavonoid intake, especially for populations consuming tropical and underutilized vegetables. PMID:18296355

  17. Gravity-induced asymmetric distribution of a plant growth hormone

    NASA Technical Reports Server (NTRS)

    Bandurski, R. S.; Schulze, A.; Momonoki, Y.

    1984-01-01

    Dolk (1936) demonstrated that gravistimulation induced an asymmetric distribution of auxin in a horizontally-placed shoot. An attempt is made to determine where and how that asymmetry arises, and to demonstrate that the endogenous auxin, indole-3-acetic acid, becomes asymmetrically distributed in the cortical cells of the Zea mays mesocotyl during 3 min of geostimulation. Further, indole-3-acetic acid derived by hydrolysis of an applied transport form of the hormone, indole-3-acetyl-myo-inositol, becomes asymmetrically distributed within 15 min of geostimulus time. From these and prior data is developed a working theory that the gravitational stimulus induces a selective leakage, or secretion, of the hormone from the vascular tissue to the cortical cells of the mesocotyl.

  18. Controls on iron distributions in the deep water column of the North Pacific Ocean: Iron(III) hydroxide solubility and marine humic-type dissolved organic matter

    NASA Astrophysics Data System (ADS)

    Kitayama, Saori; Kuma, Kenshi; Manabe, Eri; Sugie, Koji; Takata, Hyoe; Isoda, Yutaka; Toya, Kenji; Saitoh, Sei-Ichi; Takagi, Shohgo; Kamei, Yoshihiko; Sakaoka, Keiichiro

    2009-08-01

    Dissolved Fe in the western and central North Pacific Ocean was characterized by surface depletion, middepth maxima and, below that, a slight decrease with depth similar to the vertical distributions of nutrients, apparent oxygen utilization, Fe(III) hydroxide solubility, and humic-type fluorescence (H-flu) intensity. Dissolved Fe concentrations ([D-Fe], <0.22-μm fraction) in the deep water column were one-half lower in the central region (0.3-0.6 nM) than the western region (0.5-1.2 nM) although the Fe(III) solubility ([Fe(III)sol], <0.025-μm fraction) levels and distributions in deep waters were almost the same between both regions with middepth maxima (˜0.6 nM) at 500-1500-m depth range and then a gradual decrease to ˜0.3 nM at 5000-m depth. Higher [D-Fe] than [Fe(III)sol] in the deep water column of the western region results from the higher production of dissolved Fe from the decomposition of sinking particulate organic matter in the western region than the central region because of the high atmospheric and/or lateral Fe inputs in the western region. Similarity between [D-Fe] level and [Fe(III)sol] value at each deep water depth in the central region may be attributed to [D-Fe] being nearly in the solubility equilibrium with Fe(III) hydroxide in seawater. Strong linear correlation between [D-Fe] and H-flu intensity in the central region and relatively similar linear relationships between [Fe(III)sol] and H-flu intensity in the western and central regions are the first confirmation that humic-type fluorescent dissolved organic matter may be responsible for [D-Fe] in the deep water column as natural organic ligands complexing with Fe(III).

  19. Arbuscular mycorrhizal fungi associations of vascular plants confined to river valleys: towards understanding the river corridor plant distribution.

    PubMed

    Nobis, Agnieszka; Błaszkowski, Janusz; Zubek, Szymon

    2015-01-01

    The group of river corridor plants (RCP) includes vascular plant species which grow mainly or exclusively in the valleys of large rivers. Despite the long recognized fact that some plant species display a corridor-like distribution pattern in Central Europe, there is still no exhaustive explanation of the mechanisms generating this peculiar distribution. The main goal of this study was therefore to investigate whether arbuscular mycorrhizal fungi (AMF) and fungal root endophytes influence the RCP distribution. Arbuscular mycorrhizae (AM) were observed in 19 out of 33 studied RCP. Dark septate endophytes (DSE) and Olpidium spp. were recorded with low abundance in 15 and 10 plant species, respectively. The spores of AMF were found only in 32% of trap cultures established from the soils collected in the river corridor habitats. In total, six widespread AMF species were identified. Because the percentage of non-mycorrhizal species in the group of RCP is significant and the sites in river corridors are characterized by low AMF species diversity, RCP can be outcompeted outside river valleys by the widespread species that are able to benefit from AM associations in more stable plant-AMF communities in non-river habitats.

  20. Relationship between plant vascular architecture and within-plant distribution of 'Candidatus Liberibacter solanacearum' in potato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    “Candidatus Liberibacter solanacearum” is an important pathogen of Solanaceous crops that causes zebra chip disease of potato. This pathogen is transmitted among plants by the potato psyllid Bactericera cockerelli. Within-plant variability in Liberibacter infection impedes the ability to detect Lib...

  1. Distribution of the fiddler crab (Uca minax) in relation to marsh plants within a Virginia estuary

    USGS Publications Warehouse

    Kerwin, J.A.

    1971-01-01

    The distribution and abundance of the red-jointed fiddler crab, Uca minax, was related to the distribution of marsh plants within a Virginia estuary. The crab was found in association with 15 species of marsh phanerogams, occurring with five plant species more than 20 percent of the time. These plants were Spartina alterniflora, Scirpus robustus, Distichlis spicata, Spartina patens, and Spartina cynosuroides. Densities ranged from 0-76 burrows per square meter, mean densities being 7.88 within the brackish-water marsh and 14.35 within the salt-water marsh. The crab was not obtained by sampling the freshwater marsh.

  2. Distribution, congruence, and hotspots of higher plants in China

    NASA Astrophysics Data System (ADS)

    Zhao, Lina; Li, Jinya; Liu, Huiyuan; Qin, Haining

    2016-01-01

    Identifying biodiversity hotspots has become a central issue in setting up priority protection areas, especially as financial resources for biological diversity conservation are limited. Taking China’s Higher Plants Red List (CHPRL), including Bryophytes, Ferns, Gymnosperms, Angiosperms, as the data source, we analyzed the geographic patterns of species richness, endemism, and endangerment via data processing at a fine grid-scale with an average edge length of 30 km based on three aspects of richness information: species richness, endemic species richness, and threatened species richness. We sought to test the accuracy of hotspots used in identifying conservation priorities with regard to higher plants. Next, we tested the congruence of the three aspects and made a comparison of the similarities and differences between the hotspots described in this paper and those in previous studies. We found that over 90% of threatened species in China are concentrated. While a high spatial congruence is observed among the three measures, there is a low congruence between two different sets of hotspots. Our results suggest that biodiversity information should be considered when identifying biological hotspots. Other factors, such as scales, should be included as well to develop biodiversity conservation plans in accordance with the region’s specific conditions.

  3. Distribution, congruence, and hotspots of higher plants in China.

    PubMed

    Zhao, Lina; Li, Jinya; Liu, Huiyuan; Qin, Haining

    2016-01-01

    Identifying biodiversity hotspots has become a central issue in setting up priority protection areas, especially as financial resources for biological diversity conservation are limited. Taking China's Higher Plants Red List (CHPRL), including Bryophytes, Ferns, Gymnosperms, Angiosperms, as the data source, we analyzed the geographic patterns of species richness, endemism, and endangerment via data processing at a fine grid-scale with an average edge length of 30 km based on three aspects of richness information: species richness, endemic species richness, and threatened species richness. We sought to test the accuracy of hotspots used in identifying conservation priorities with regard to higher plants. Next, we tested the congruence of the three aspects and made a comparison of the similarities and differences between the hotspots described in this paper and those in previous studies. We found that over 90% of threatened species in China are concentrated. While a high spatial congruence is observed among the three measures, there is a low congruence between two different sets of hotspots. Our results suggest that biodiversity information should be considered when identifying biological hotspots. Other factors, such as scales, should be included as well to develop biodiversity conservation plans in accordance with the region's specific conditions. PMID:26750244

  4. Distribution, congruence, and hotspots of higher plants in China

    PubMed Central

    Zhao, Lina; Li, Jinya; Liu, Huiyuan; Qin, Haining

    2016-01-01

    Identifying biodiversity hotspots has become a central issue in setting up priority protection areas, especially as financial resources for biological diversity conservation are limited. Taking China’s Higher Plants Red List (CHPRL), including Bryophytes, Ferns, Gymnosperms, Angiosperms, as the data source, we analyzed the geographic patterns of species richness, endemism, and endangerment via data processing at a fine grid-scale with an average edge length of 30 km based on three aspects of richness information: species richness, endemic species richness, and threatened species richness. We sought to test the accuracy of hotspots used in identifying conservation priorities with regard to higher plants. Next, we tested the congruence of the three aspects and made a comparison of the similarities and differences between the hotspots described in this paper and those in previous studies. We found that over 90% of threatened species in China are concentrated. While a high spatial congruence is observed among the three measures, there is a low congruence between two different sets of hotspots. Our results suggest that biodiversity information should be considered when identifying biological hotspots. Other factors, such as scales, should be included as well to develop biodiversity conservation plans in accordance with the region’s specific conditions. PMID:26750244

  5. Sub-Chronic Oral Exposure to Iridium (III) Chloride Hydrate in Female Wistar Rats: Distribution and Excretion of the Metal

    PubMed Central

    Iavicoli, Ivo; Fontana, Luca; Bergamaschi, Antonio; Conti, Marcelo Enrique; Pino, Anna; Mattei, Daniela; Bocca, Beatrice; Alimonti, Alessandro

    2012-01-01

    Iridium tissue distribution and excretion in female Wistar rats following oral exposure to iridium (III) chloride hydrate in drinking water (from 1 to 1000 ng/ml) in a sub-chronic oral study were determined. Samples of urine, feces, blood and organs (kidneys, liver, lung, spleen and brain) were collected at the end of exposure. The most prominent fractions of iridium were retained in kidney and spleen; smaller amounts were found in lungs, liver and brain. Iridium brain levels were lower than those observed in other tissues but this finding can support the hypothesis of iridium capability to cross the blood brain barrier. The iridium kidney levels rose significantly with the administered dose. At the highest dose, important amounts of the metal were found in serum, urine and feces. Iridium was predominantly excreted via feces with a significant linear correlation with the ingested dose, which is likely due to low intestinal absorption of the metal. However, at the higher doses iridium was also eliminated through urine. These findings may be useful to help in the understanding of the adverse health effects, particularly on the immune system, of iridium dispersed in the environment as well as in identifying appropriate biological indices of iridium exposure. PMID:22942873

  6. The binomial distribution of hydrogen and deuterium in arsanes, diarsanes, and triarsanes generated from As(III)/[BH(n)D(4-n)]- and the effect of trace amounts of Rh(III) ions.

    PubMed

    Pagliano, Enea; D'Ulivo, Alessandro; Mester, Zoltán; Sturgeon, Ralph E; Meija, Juris

    2012-12-01

    Recent studies of the formation of arsane in the borohydride/arsenate reaction demonstrate the occurrence of condensation cascades whereby small quantities of di- and triarsanes are formed. In this study, the isotopic composition of these di- and triarsanes was examined using deuterium labelled borohydrides. A statistical model was employed to construct the mass spectra of all diarsane and triarsane isotopologues (As(2)H(n)D(4-n) and As(3)H(n)D(5-n)) from the mass spectra of isotopically pure compounds (As(2)H(4), As(2)D(4), As(3)H(5), and As(3)D(5)). Subsequent deconvolution of the experimental mixed spectra shows that incorporation of hydrogen closely follows the binomial distribution, in accord with arsane formation. The H/D distribution in arsane, diarsane, and triarsane isotopologues is binomial in the absence of any interference. However, this is significantly altered by the presence of some transition metals; presented here, for the first time, are the effects of Rh(III). The presence of Rh(III) in the As(III)/[BD(4)](-) system entails the incorporation of hydrogen into the arsanes arising from the solvent, altering the expected binomial H/D distribution.

  7. Multiple Activities of the Plant Pathogen Type III Effector Proteins WtsE and AvrE1 require WxxxE Motifs

    PubMed Central

    Ham, Jong Hyun; Majerczak, Doris R.; Nomura, Kinya; Mecey, Christy; Uribe, Francisco; He, Sheng-Yang; Mackey, David; Coplin, David L.

    2009-01-01

    The broadly conserved AvrE-family of type III effectors from Gram-negative plant pathogenic bacteria includes important virulence factors, yet little is known about the mechanisms by which these effectors function inside plant cells to promote disease. We have identified two conserved motifs in AvrE-family effectors: a WxxxE motif and a putative C-terminal endoplasmic reticulum membrane retention/retrieval signal (ERMRS). The WxxxE and ERMRS motifs are both required for the virulence activities of WtsE and AvrE1, which are major virulence factors of the corn pathogen Pantoea stewartii subsp. stewartii and the tomato/Arabidopsis pathogen Pseudomonas syringae pv. tomato, respectively. The WxxxE and the predicted ERMRS motifs are also required for other biological activities of WtsE, including elicitation of the hypersensitive response in nonhost plants and suppression of defense responses in Arabidopsis. A family of type III effectors from mammalian bacterial pathogens requires WxxxE and sub-cellular targeting motifs for virulence functions that involve their ability to mimic activated G-proteins. The conservation of related motifs and their necessity for the function of type III effectors from plant pathogens indicates that disturbing host pathways by mimicking activated host G-proteins may be a virulence mechanism employed by plant pathogens as well. PMID:19445595

  8. Comparisons of two moments-based estimators that utilize historical and paleoflood data for the log Pearson type III distribution

    USGS Publications Warehouse

    England, J.F.; Salas, J.D.; Jarrett, R.D.

    2003-01-01

    The expected moments algorithm (EMA) [Cohn et al., 1997] and the Bulletin 17B [Interagency Committee on Water Data, 1982] historical weighting procedure (B17H) for the log Pearson type III distribution are compared by Monte Carlo computer simulation for cases in which historical and/or paleoflood data are available. The relative performance of the estimators was explored for three cases: fixed-threshold exceedances, a fixed number of large floods, and floods generated from a different parent distribution. EMA can effectively incorporate four types of historical and paleoflood data: floods where the discharge is explicitly known, unknown discharges below a single threshold, floods with unknown discharge that exceed some level, and floods with discharges described in a range. The B17H estimator can utilize only the first two types of historical information. Including historical/paleoflood data in the simulation experiments significantly improved the quantile estimates in terms of mean square error and bias relative to using gage data alone. EMA performed significantly better than B17H in nearly all cases considered. B17H performed as well as EMA for estimating X100 in some limited fixed-threshold exceedance cases. EMA performed comparatively much better in other fixed-threshold situations, for the single large flood case, and in cases when estimating extreme floods equal to or greater than X500. B17H did not fully utilize historical information when the historical period exceeded 200 years. Robustness studies using GEV-simulated data confirmed that EMA performed better than B17H. Overall, EMA is preferred to B17H when historical and paleoflood data are available for flood frequency analysis.

  9. Evaluation of the Environmental DNA Method for Estimating Distribution and Biomass of Submerged Aquatic Plants

    PubMed Central

    Matsuhashi, Saeko; Doi, Hideyuki; Fujiwara, Ayaka; Watanabe, Sonoko; Minamoto, Toshifumi

    2016-01-01

    The environmental DNA (eDNA) method has increasingly been recognized as a powerful tool for monitoring aquatic animal species; however, its application for monitoring aquatic plants is limited. To evaluate eDNA analysis for estimating the distribution of aquatic plants, we compared its estimated distributions with eDNA analysis, visual observation, and past distribution records for the submerged species Hydrilla verticillata. Moreover, we conducted aquarium experiments using H. verticillata and Egeria densa and analyzed the relationships between eDNA concentrations and plant biomass to investigate the potential for biomass estimation. The occurrences estimated by eDNA analysis closely corresponded to past distribution records, and eDNA detections were more frequent than visual observations, indicating that the method is potentially more sensitive. The results of the aquarium experiments showed a positive relationship between plant biomass and eDNA concentration; however, the relationship was not always significant. The eDNA concentration peaked within three days of the start of the experiment in most cases, suggesting that plants do not release constant amounts of DNA. These results showed that eDNA analysis can be used for distribution surveys, and has the potential to estimate the biomass of aquatic plants. PMID:27304876

  10. Evaluation of the Environmental DNA Method for Estimating Distribution and Biomass of Submerged Aquatic Plants.

    PubMed

    Matsuhashi, Saeko; Doi, Hideyuki; Fujiwara, Ayaka; Watanabe, Sonoko; Minamoto, Toshifumi

    2016-01-01

    The environmental DNA (eDNA) method has increasingly been recognized as a powerful tool for monitoring aquatic animal species; however, its application for monitoring aquatic plants is limited. To evaluate eDNA analysis for estimating the distribution of aquatic plants, we compared its estimated distributions with eDNA analysis, visual observation, and past distribution records for the submerged species Hydrilla verticillata. Moreover, we conducted aquarium experiments using H. verticillata and Egeria densa and analyzed the relationships between eDNA concentrations and plant biomass to investigate the potential for biomass estimation. The occurrences estimated by eDNA analysis closely corresponded to past distribution records, and eDNA detections were more frequent than visual observations, indicating that the method is potentially more sensitive. The results of the aquarium experiments showed a positive relationship between plant biomass and eDNA concentration; however, the relationship was not always significant. The eDNA concentration peaked within three days of the start of the experiment in most cases, suggesting that plants do not release constant amounts of DNA. These results showed that eDNA analysis can be used for distribution surveys, and has the potential to estimate the biomass of aquatic plants. PMID:27304876

  11. Plant Minders

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Indoor plants are automatically watered by the Aqua Trends watering system. System draws water from building outlets or from pump/reservoir module and distributes it to the plants via a network of tubes and adjustable nozzles. Key element of system is electronic controller programmed to dispense water according to the needs of various plants in an installation. Adjustable nozzle meters out exactly right amount of water at proper time to the plant it's serving. More than 100 Aqua/Trends systems are in service in the USA, from a simple residential system to a large Mirage III system integrated to water all greenery in a large office or apartment building.

  12. Defining the distribution of arsenic species and plant nutrients in rice ( Oryza sativa L.) from the root to the grain

    NASA Astrophysics Data System (ADS)

    Seyfferth, Angelia L.; Webb, Samuel M.; Andrews, Joy C.; Fendorf, Scott

    2011-11-01

    The transport mechanisms of As from contaminated soil or irrigation water into roots and subsequently into grain, and the As species distribution—a toxicity determinant, is critical for assessing health risks imposed by As. However, the commonly-employed extraction of plant material with trifluoroacetic acid (TFA) has not proven successful in preserving inorganic As species. Synchrotron-based spectroscopic techniques are useful for discerning elemental distributions and chemical speciation of elements in situ. Here, we both characterize the mineral phases of Fe coatings on rice roots, and quantify plant nutrients and As species in situ on roots and grain samples. Arsenic in rice grains was present in bran layers as oxidized As (69-88% as As(V) i and 12-31% as DMA) and in the germ as a mixture of As(V) i and As(III) i, but was non-detected from the endosperm, which is consistent with previous findings. The extent of Fe coatings on rice roots was variable and, when present, consisted of lepidocrocite (γ-FeOOH), goethite (α-FeOOH) and ferrihydrite (Fe(OH) 3· nH 2O). Arsenic was co-located with root Fe coatings, but our findings indicate that Fe is not a direct interceptor of As uptake, and is rather a bulk scavenger mostly near the air-water interface. On whole root mounts with Fe plaque, arsenic was present as mixed species of As(V) i (44-66%) and As(III) i (34-56%). Within a root cross-section, oxidized As species were dominant in the xylem (86% as As(V) i and 14% as DMA) whereas mostly reduced species (71% as As(III) i, 29% as AsGlu 3) resided within a vacuole adjacent to the xylem. This finding contrasts the prevailing view that As(V) i is rapidly reduced in roots and transported to shoots as As(III) i, and points to the importance of interspecies differences in As-uptake dynamics.

  13. Functional characterization of a class III acid endochitinase from the traps of the carnivorous pitcher plant genus, Nepenthes.

    PubMed

    Rottloff, Sandy; Stieber, Regina; Maischak, Heiko; Turini, Florian G; Heubl, Günther; Mithöfer, Axel

    2011-08-01

    Carnivory in plants is an adaptation strategy to nutrient-poor environments and soils. Carnivorous plants obtain some additional mineral nutrients by trapping and digesting prey; the genus Nepenthes is helped by its specialized pitcher traps. To make the nutrients available, the caught prey needs to be digested, a process that requires the concerted activity of several hydrolytic enzymes. To identify and investigate the various enzymes involved in this process, fluid from Nepenthes traps has been analysed in detail. In this study, a novel type of Nepenthes endochitinase was identified in the digestion fluid of closed pitchers. The encoding endochitinase genes have been cloned from eight different Nepenthes species. Among these, the deduced amino acid sequence similarity was at least 94.9%. The corresponding cDNA from N. rafflesiana was heterologously expressed, and the purified protein, NrChit1, was biochemically characterized. The enzyme, classified as a class III acid endochitinase belonging to family 18 of the glycoside hydrolases, is secreted into the pitcher fluid very probably due to the presence of an N-terminal signal peptide. Transcriptome analyses using real-time PCR indicated that the presence of prey in the pitcher up-regulates the endochitinase gene not only in the glands, which are responsible for enzyme secretion, but at an even higher level, in the glands' surrounding tissue. These results suggest that in the pitchers' tissues, the endochitinase as well as other proteins from the pitcher fluid might fulfil a different, primary function as pathogenesis-related proteins. PMID:21633084

  14. Sb(V) and Sb(III) distribution in human erythrocytes: speciation methodology and the influence of temperature, time and anticoagulants.

    PubMed

    Quiroz, Waldo; Aguilar, Luis; Barría, Macarena; Veneciano, Jocelyn; Martínez, Daniel; Bravo, Manuel; Lobos, María Gabriela; Mercado, Luis

    2013-10-15

    In this research a new method was developed and optimized for the determination of Sb(V) and Sb(III) in human erythrocytes fractions (plasma and cytoplasm) by high performance liquid chromatography with hydride generation atomic fluorescence spectrometry. The method considers the first step of samples cleaning by protein precipitation by salting out followed by C18 solid phase extraction, EDTA elution, and finally a chromatographic separation by using anion exchange PRPX-100 (100 mm × 4.1mm) and EDTA 20 mmol L(-1) as mobile phase. The method was optimized by experimental design with a recovery of 90% for Sb(V) and 55-75% for Sb(III) approximately. The analytical method was applied to study the distribution of Sb(V) and Sb(III) in human erythrocytes considering temperature and time of incubations and with special attention about the influence of the anticoagulant. Results showed that both Sb(V) and Sb(III) are capable to enter the red blood cell in a proportion of approximately 40-60%. On the other hand, both species are then excreted from the interior of the cell, where the percentage considerably decreased from approximately 60 to less than 30% within the cell. An increase in the culture temperature increases the capacity of Sb(V) and Sb(III) to penetrate the membrane barrier and reach the cytoplasm. In order to preserve the original distribution of Sb in blood, heparin seems to be the best anticoagulant for sample preservation.

  15. Distribution of radiocesium in the soil-plant systems of upland areas of Europe

    SciTech Connect

    Livens, F.R.; Horrill, A.D.; Singleton, D.L. )

    1991-04-01

    The distribution and behavior of Cs in the soil-plant systems at some upland sites in Northeastern Italy, Scotland, and Norway have been investigated. From the limited range of samples taken, there appears to be no dominant physicochemical control on the plant availability of Cs. The presence of micaceous minerals or illitic clays does not significantly inhibit Cs uptake, either because of recycling in the organic surface horizons or because of clay-organic complex formation. Lower plants (bryophytes and lichens) show the highest Cs accumulation. Of the higher plants, ericaceous species take up Cs more than the others.

  16. Plant distribution-altitude and landform relationships in karstic sinkholes of Mediterranean region of Turkey.

    PubMed

    Ozkan, Kürsad; Gulsoy, Serkan; Mert, Ahmet; Ozturk, Munir; Muys, Bart

    2010-01-01

    The purpose of this study was to investigate the relationships between the plant distribution and the altitude-shape-size characteristics of sinkholes, and the landform characteristics inside sinkholes in the Mediterranean region of Turkey. Block kriging, Factor analysis, Cluster Analysis and Detrended Correspondence Analysis were performed. The sinkhole type and altitudinal zone were found to be the significant factors affecting the plant distribution. However, the sinkhole type was more important than the altitudinal zone. Hence, the sinkholes were first subdivided into groups according to types and then the groups were divided into subgroups according to the altitudinal zones. Consequently, 4 groups were defined; A-type sinkholes [1400-1550 m (A1), 1550-1700 m (A2)] and B-type sinkholes [1400-1550 (B1), 1550-1700 m (B2)]. The B-type was wider vertically and shorter horizontally than A-type sinkholes. Significant differences were found between the plant distribution and slope position inside the sinkholes. Plant distribution in the lower slopes was different from that in the flats and ridges in the B1 sub-type of B-type. Plant distribution in B2 subtype was different among the slope positions (ridge, middle slope, lower slope, and flat). Although distribution of plants is different in different parts (ridges, upper slope, middle slope, lower slope and basal flats) of A sinkhole, the differences between the parts of intermediate slope position are not significant. A high plant variability along short distances in the sinkholes was observed in the study area. That is why the site of sinkholes have a big potential for the distribution of many species. Hence, the area must be separated as strictly protected zone.

  17. A continuous spectrophotometric assay for the activation of plant NAD kinase by calmodulin, calcium(II), and europium(III) ions.

    PubMed

    Amann, B T; Mulqueen, P; Horrocks, W D

    1992-12-01

    A continuous spectrophotometric assay has been developed to quantify the calmodulin, calcium(II) ion, and europium(III) ion dependence of the activation of NAD kinase from pea seedlings. Experimental enzyme activation data are compared with the theoretical curves for the binding of calcium(II) ions to the individual calcium binding sites of calmodulin. These results indicate that the binding of three calcium(II) ions is necessary for activation of plant NAD kinase. Further studies demonstrate that europium(III) ions can replace calcium(II) ions in calmodulin with retention of its ability to activate NAD kinase.

  18. The production of class III plant peroxidases in transgenic callus cultures transformed with the rolB gene of Agrobacterium rhizogenes.

    PubMed

    Shkryl, Y N; Veremeichik, G N; Bulgakov, V P; Avramenko, T V; Günter, E A; Ovodov, Y S; Muzarok, T I; Zhuravlev, Y N

    2013-10-10

    The production of plant peroxidases by plant cell cultures is of great interest because of the potential for industrial applications. We used plant cell cultures overexpressing the rolB gene to produce increased amounts of plant class III peroxidases. The rolB gene ensured the stable and permanent activation of peroxidase activity in the transformed callus cultures of different plants. In particular, the total peroxidase activity in transformed Rubia cordifolia cells was increased 23-86-fold, and the abundance of the major peroxidase gene transcripts was increased 17-125-fold (depending on the level of rolB expression) compared with non-transformed control calli. The peroxidase-activating effect of rolB was greater than that of other peroxidase inducers, such as external stresses and methyl jasmonate.

  19. Hyperspectral imaging for mapping of total nitrogen spatial distribution in pepper plant.

    PubMed

    Yu, Ke-Qiang; Zhao, Yan-Ru; Li, Xiao-Li; Shao, Yong-Ni; Liu, Fei; He, Yong

    2014-01-01

    Visible/near-infrared (Vis/NIR) hyperspectral imaging was employed to determine the spatial distribution of total nitrogen in pepper plant. Hyperspectral images of samples (leaves, stems, and roots of pepper plants) were acquired and their total nitrogen contents (TNCs) were measured using Dumas combustion method. Mean spectra of all samples were extracted from regions of interest (ROIs) in hyperspectral images. Random frog (RF) algorithm was implemented to select important wavelengths which carried effective information for predicting the TNCs in leaf, stem, root, and whole-plant (leaf-stem-root), respectively. Based on full spectra and the selected important wavelengths, the quantitative relationships between spectral data and the corresponding TNCs in organs (leaf, stem, and root) and whole-plant (leaf-stem-root) were separately developed using partial least-squares regression (PLSR). As a result, the PLSR model built by the important wavelengths for predicting TNCs in whole-plant (leaf-stem-root) offered a promising result of correlation coefficient (R) for prediction (RP = 0.876) and root mean square error (RMSE) for prediction (RMSEP = 0.426%). Finally, the TNC of each pixel within ROI of the sample was estimated to generate the spatial distribution map of TNC in pepper plant. The achievements of the research indicated that hyperspectral imaging is promising and presents a powerful potential to determine nitrogen contents spatial distribution in pepper plant.

  20. Distribution of Cenozoic plant relicts in China explained by drought in dry season.

    PubMed

    Huang, Yongjiang; Jacques, Frédéric M B; Su, Tao; Ferguson, David K; Tang, Hui; Chen, Wenyun; Zhou, Zhekun

    2015-01-01

    Cenozoic plant relicts are those groups that were once widespread in the Northern Hemisphere but are now restricted to some small isolated areas as a result of drastic climatic changes. They are good proxies to study how plants respond to climatic changes since their modern climatic requirements are known. Herein we look at the modern distribution of 65 palaeoendemic genera in China and compare it with the Chinese climatic pattern, in order to find a link between the plant distribution and climate. Central China and Taiwan Island are shown to be diversity centres of Cenozoic relict genera, consistent with the fact that these two regions have a shorter dry season with comparatively humid autumn and spring in China. Species distribution models indicate that the precipitation parameters are the most important variables to explain the distribution of relict genera. The Cenozoic wide-scale distribution of relict plants in the Northern Hemisphere is therefore considered to be linked to the widespread humid climate at that time, and the subsequent contraction of their distributional ranges was probably caused by the drying trend along with global cooling. PMID:26369980

  1. Distribution of Cenozoic plant relicts in China explained by drought in dry season.

    PubMed

    Huang, Yongjiang; Jacques, Frédéric M B; Su, Tao; Ferguson, David K; Tang, Hui; Chen, Wenyun; Zhou, Zhekun

    2015-09-15

    Cenozoic plant relicts are those groups that were once widespread in the Northern Hemisphere but are now restricted to some small isolated areas as a result of drastic climatic changes. They are good proxies to study how plants respond to climatic changes since their modern climatic requirements are known. Herein we look at the modern distribution of 65 palaeoendemic genera in China and compare it with the Chinese climatic pattern, in order to find a link between the plant distribution and climate. Central China and Taiwan Island are shown to be diversity centres of Cenozoic relict genera, consistent with the fact that these two regions have a shorter dry season with comparatively humid autumn and spring in China. Species distribution models indicate that the precipitation parameters are the most important variables to explain the distribution of relict genera. The Cenozoic wide-scale distribution of relict plants in the Northern Hemisphere is therefore considered to be linked to the widespread humid climate at that time, and the subsequent contraction of their distributional ranges was probably caused by the drying trend along with global cooling.

  2. Distribution of Cenozoic plant relicts in China explained by drought in dry season

    PubMed Central

    Huang, Yongjiang; Jacques, Frédéric M. B.; Su, Tao; Ferguson, David K.; Tang, Hui; Chen, Wenyun; Zhou, Zhekun

    2015-01-01

    Cenozoic plant relicts are those groups that were once widespread in the Northern Hemisphere but are now restricted to some small isolated areas as a result of drastic climatic changes. They are good proxies to study how plants respond to climatic changes since their modern climatic requirements are known. Herein we look at the modern distribution of 65 palaeoendemic genera in China and compare it with the Chinese climatic pattern, in order to find a link between the plant distribution and climate. Central China and Taiwan Island are shown to be diversity centres of Cenozoic relict genera, consistent with the fact that these two regions have a shorter dry season with comparatively humid autumn and spring in China. Species distribution models indicate that the precipitation parameters are the most important variables to explain the distribution of relict genera. The Cenozoic wide-scale distribution of relict plants in the Northern Hemisphere is therefore considered to be linked to the widespread humid climate at that time, and the subsequent contraction of their distributional ranges was probably caused by the drying trend along with global cooling. PMID:26369980

  3. [Distribution pattern of rare plants along riparian zone and its implication for conservation in Shennongjia area].

    PubMed

    Jiang, Mingxi; Deng, Hongbing; Cai, Qinghua

    2002-11-01

    Due to the importance of riparian zone in maintaining and protecting regional biodiversity, more and more ecologists paid their attentions to riparian zone, and had been aware of the important effects of riparian zone in basic study and practical management. In this study, forty sampling belts (10 m x 100 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia area were selected to investigate the riparian vegetation and rare plants. Fourteen species of rare plants were found in riparian zone, accounting for 42.4% of total rare plant species in Shennongjia area. The main distribution range of the fourteen rare plant species was the mixed evergreen and deciduous broadleaved forest at elevation of 1200-1800 m, where species diversity of plant community was the maximum at the moderate elevation. Fourteen rare plant species could be divided into three groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation group. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out the important function of riparian zone on rare plant species protection.

  4. Subcellular location of horseradish peroxidase in horseradish leaves treated with La(III), Ce(III) and Tb(III).

    PubMed

    Ye, Yaxin; Wang, Lihong; Huang, Xiaohua; Lu, Tianhong; Ding, Xiaolan; Zhou, Qing; Guo, Shaofen

    2008-11-01

    The agricultural application of rare-earth elements (REEs) would promote REEs inevitably to enter in the environment and then to threaten the environmental safety and human health. Therefore, the distribution of the REEs ion, (141)Ce(III) and effects of La(III), Ce(III) and Tb(III) on the distribution of horseradish peroxidase (HRP) in horseradish mesophyll cells were investigated with electron microscopic radioautography and transmission electron microscopic cytochemistry. It was found for the first time that REEs ions can enter into the mesophyll cells, deposit in both extra and intra-cellular. Compared to the normal condition, after the horseradish leaves treated with La(III) or Tb(III), HRP located on the tonoplast is decreased and HRP is mainly located on the cell wall, while HRP is mainly located on the plasma membrane after the horseradish leaves were treated with Ce(III). This also indicated that REEs ions may regulate the plant growth through changing the distribution of enzymes.

  5. Determination of microelement distribution in different components of soil-plant systems

    NASA Astrophysics Data System (ADS)

    Hung, Luu Viet; Maslov, O. D.; Gustova, M. V.; My, Trinh Thi Thu; Ho, Phung Khac Nam

    2011-07-01

    The leaves, stem, and roots of two types of shrubs (tea ( Camellia sinensis) and sweet leaf ( Sauropus androgynus)) and two types of herbs (vetiver grass ( Vetiveria zizanioides L. Nash) and maize ( Zea mays L)) and the Thucuc soil where the plants were growing were collected to be studied. The contents of 22 elements in the samples were determined by three methods: X-Ray fluorescence analysis (XRFA), gamma activation analysis (GAA), and the tracking method to study the distribution of these elements in plants and the soil-plant relationship. This study was carried out at the Flerov Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research (JINR), Dubna, Russia. The distribution of the elements in the soil-plant system was studied.

  6. Woody plant encroachment into grasslands: spatial patterns of functional group distribution and community development.

    PubMed

    Liu, Feng; Archer, Steven R; Gelwick, Frances; Bai, Edith; Boutton, Thomas W; Wu, Xinyuan Ben

    2013-01-01

    Woody plant encroachment into grasslands has been globally widespread. The woody species invading grasslands represent a variety of contrasting plant functional groups and growth forms. Are some woody plant functional types (PFTs) better suited to invade grasslands than others? To what extent do local patterns of distribution and abundance of woody PFTs invading grasslands reflect intrinsic topoedaphic properties versus plant-induced changes in soil properties? We addressed these questions in the Southern Great Plains, United States at a subtropical grassland known to have been encroached upon by woody species over the past 50-100 years. A total of 20 woody species (9 tree-statured; 11 shrub-statured) were encountered along a transect extending from an upland into a playa basin. About half of the encroaching woody plants were potential N2-fixers (55% of species), but they contributed only 7% to 16 % of the total basal area. Most species and the PFTs they represent were ubiquitously distributed along the topoedaphic gradient, but with varying abundances. Overstory-understory comparisons suggest that while future species composition of these woody communities is likely to change, PFT composition is not. Canonical correspondence analysis (CCA) ordination and variance partitioning (Partial CCA) indicated that woody species and PFT composition in developing woody communities was primarily influenced by intrinsic landscape location variables (e.g., soil texture) and secondarily by plant-induced changes in soil organic carbon and total nitrogen content. The ubiquitous distribution of species and PFTs suggests that woody plants are generally well-suited to a broad range of grassland topoedaphic settings. However, here we only examined categorical and non-quantitative functional traits. Although intrinsic soil properties exerted more control over the floristics of grassland-to-woodland succession did plant modifications of soil carbon and nitrogen concentrations, the latter

  7. Woody plant encroachment into grasslands: spatial patterns of functional group distribution and community development.

    PubMed

    Liu, Feng; Archer, Steven R; Gelwick, Frances; Bai, Edith; Boutton, Thomas W; Wu, Xinyuan Ben

    2013-01-01

    Woody plant encroachment into grasslands has been globally widespread. The woody species invading grasslands represent a variety of contrasting plant functional groups and growth forms. Are some woody plant functional types (PFTs) better suited to invade grasslands than others? To what extent do local patterns of distribution and abundance of woody PFTs invading grasslands reflect intrinsic topoedaphic properties versus plant-induced changes in soil properties? We addressed these questions in the Southern Great Plains, United States at a subtropical grassland known to have been encroached upon by woody species over the past 50-100 years. A total of 20 woody species (9 tree-statured; 11 shrub-statured) were encountered along a transect extending from an upland into a playa basin. About half of the encroaching woody plants were potential N2-fixers (55% of species), but they contributed only 7% to 16 % of the total basal area. Most species and the PFTs they represent were ubiquitously distributed along the topoedaphic gradient, but with varying abundances. Overstory-understory comparisons suggest that while future species composition of these woody communities is likely to change, PFT composition is not. Canonical correspondence analysis (CCA) ordination and variance partitioning (Partial CCA) indicated that woody species and PFT composition in developing woody communities was primarily influenced by intrinsic landscape location variables (e.g., soil texture) and secondarily by plant-induced changes in soil organic carbon and total nitrogen content. The ubiquitous distribution of species and PFTs suggests that woody plants are generally well-suited to a broad range of grassland topoedaphic settings. However, here we only examined categorical and non-quantitative functional traits. Although intrinsic soil properties exerted more control over the floristics of grassland-to-woodland succession did plant modifications of soil carbon and nitrogen concentrations, the latter

  8. Woody Plant Encroachment into Grasslands: Spatial Patterns of Functional Group Distribution and Community Development

    PubMed Central

    Liu, Feng; Archer, Steven R.; Gelwick, Frances; Bai, Edith; Boutton, Thomas W.; Wu, Xinyuan Ben

    2013-01-01

    Woody plant encroachment into grasslands has been globally widespread. The woody species invading grasslands represent a variety of contrasting plant functional groups and growth forms. Are some woody plant functional types (PFTs) better suited to invade grasslands than others? To what extent do local patterns of distribution and abundance of woody PFTs invading grasslands reflect intrinsic topoedaphic properties versus plant-induced changes in soil properties? We addressed these questions in the Southern Great Plains, United States at a subtropical grassland known to have been encroached upon by woody species over the past 50-100 years. A total of 20 woody species (9 tree-statured; 11 shrub-statured) were encountered along a transect extending from an upland into a playa basin. About half of the encroaching woody plants were potential N2-fixers (55% of species), but they contributed only 7% to 16 % of the total basal area. Most species and the PFTs they represent were ubiquitously distributed along the topoedaphic gradient, but with varying abundances. Overstory-understory comparisons suggest that while future species composition of these woody communities is likely to change, PFT composition is not. Canonical correspondence analysis (CCA) ordination and variance partitioning (Partial CCA) indicated that woody species and PFT composition in developing woody communities was primarily influenced by intrinsic landscape location variables (e.g., soil texture) and secondarily by plant-induced changes in soil organic carbon and total nitrogen content. The ubiquitous distribution of species and PFTs suggests that woody plants are generally well-suited to a broad range of grassland topoedaphic settings. However, here we only examined categorical and non-quantitative functional traits. Although intrinsic soil properties exerted more control over the floristics of grassland-to-woodland succession did plant modifications of soil carbon and nitrogen concentrations, the latter

  9. The Distribution of Plants on Habitable Planet around M-dwarfs

    NASA Astrophysics Data System (ADS)

    Cui, Duo

    2015-12-01

    Previous studies show that habitable exoplanets around M dwarfs may have two climate patterns, an eyeball climate pattern and a striped-ball climate pattern, depending on the spin-orbit period ratio. The two climate patterns are included into the DNDC (denitrification-decomposition) model, which is modified to accommodate the climate and stellar light conditions different than those on the Earth, to investigate the growth of plants on the corresponding planets. The pattern of plant distribution correlates well with the climate pattern, which is consistent with the close link between plant growth and climate.

  10. AgRISTARS: Supporting research. Spring small grains planting date distribution model

    NASA Technical Reports Server (NTRS)

    Hodges, T.; Artley, J. A. (Principal Investigator)

    1981-01-01

    A model was developed using 996 planting dates at 51 LANDSAT segments for spring wheat and spring barley in Minnesota, Montana, North Dakota, and South Dakota in 1979. Daily maximum and minimum temperatures and precipitation were obtained from the cooperative weather stations nearest to each segment. The model uses a growing degree day summation modified for daily temperature range to estimate the beginning of planting and uses a soil surface wetness variable to estimate how a fixed number of planting days are distributed after planting begins. For 1979, the model predicts first, median, and last planting dates with root mean square errors of 7.91, 6.61, and 7.09 days, respectively. The model also provides three or four dates to represent periods of planting activity within the planting season. Although the full model was not tested on an independent data set, it may be suitable in areas other than the U.S. Great Plains where spring small grains are planted as soon as soil and air temperatures become warm enough in the spring for plant growth.

  11. A brief review on anti diabetic plants: Global distribution, active ingredients, extraction techniques and acting mechanisms

    PubMed Central

    Chan, Chung-Hung; Ngoh, Gek-Cheng; Yusoff, Rozita

    2012-01-01

    A study has been conducted with the aim to provide researchers with general information on anti diabetic extracts based on relevant research articles collected from 34 reliable medical journals. The study showed that Asian and African continents have 56% and 17% share of the worldwide distribution of therapeutic herbal plants, respectively. In Asia, India and China are the leading countries in herbal plants research, and there has been an increase in medicinal research on plants extract for diabetes treatment since 1995 in these regions. The information collected shows that plant leaves are about 20% more favorable for storing active ingredients, as compared to other parts of herbal plants. A brief review on the extraction techniques for the mentioned parts is also included. Furthermore, the acting mechanisms for the anti diabetic activity were described, and the related active ingredients were identified. The findings reveal that most of the anti diabetic research is focused on the alteration of glucose metabolism to prevent diabetes. PMID:22654401

  12. Approaches in the Determination of Plant Nutrient Uptake and Distribution in Space Flight Conditions

    NASA Technical Reports Server (NTRS)

    Heyenga, A. G.; Forsman, A.; Stodieck, L. S.; Hoehn, A.; Kliss, Mark

    1998-01-01

    The effective growth and development of vascular plants rely on the adequate availability of water and nutrients. Inefficiency in either the initial absorption, transportation, or distribution of these elements are factors which may impinge on plant structure and metabolic integrity. The potential effect of space flight and microgravity conditions on the efficiency of these processes is unclear. Limitations in the available quantity of space-grown plant material and the sensitivity of routine analytical techniques have made an evaluation of these processes impractical. However, the recent introduction of new plant cultivating methodologies supporting the application of radionuclide elements and subsequent autoradiography techniques provides a highly sensitive investigative approach amenable to space flight studies. Experiments involving the use of gel based 'nutrient packs' and the nuclides Ca45 and Fe59 were conducted on the Shuttle mission STS-94. Uptake rates of the radionuclides between ground and flight plant material appeared comparable.

  13. Approaches in the determination of plant nutrient uptake and distribution in space flight conditions

    NASA Technical Reports Server (NTRS)

    Heyenga, A. G.; Forsman, A.; Stodieck, L. S.; Hoehn, A.; Kliss, M.

    2000-01-01

    The effective growth and development of vascular plants rely on the adequate availability of water and nutrients. Inefficiency in either the initial absorption, transportation, or distribution of these elements are factors which impinge on plant structure and metabolic integrity. The potential effect of space flight and microgravity conditions on the efficiency of these processes is unclear. Limitations in the available quantity of space-grown plant material and the sensitivity of routine analytical techniques have made an evaluation of these processes impractical. However, the recent introduction of new plant cultivating methodologies supporting the application of radionuclide elements and subsequent autoradiography techniques provides a highly sensitive investigative approach amenable to space flight studies. Experiments involving the use of gel based 'nutrient packs' and the radionuclides calcium-45 and iron-59 were conducted on the Shuttle mission STS-94. Uptake rates of the radionuclides between ground and flight plant material appeared comparable.

  14. Thallium speciation in plant tissues-Tl(III) found in Sinapis alba L. grown in soil polluted with tailing sediment containing thallium minerals.

    PubMed

    Krasnodębska-Ostręga, Beata; Sadowska, Monika; Ostrowska, Sylwia

    2012-05-15

    Besides the dominant species in plants-Tl(I), noticeable amounts of Tl(III) (about 10% of total Tl content) were found in extracts of plants cultivated in the presence of tailing sediments, which are the main source of anthropogenic thallium already present in the environment. It is an important step of gaining knowledge about the detoxification mechanisms developed by Sinapis alba. This plant species is highly tolerant to Tl and it is able to cumulate high amounts of Tl and transport it into the above-ground organs. For more adequate estimation of accumulating abilities of S. alba, the elements' bioavailability was taken into consideration. The obtained bioconcentration factors of Cd (AF=0.6) and Zn (AF=1-2) were significantly lower than of Tl (AF=100-200). The biomass production was similar to the biomass of control cultivation. The results were based on ICP MS measurements of total elements' content and HPLC ICP MS for speciation analysis. The quality of obtained results was evaluated based on the intermethod comparison with voltammetry as a reference method. Comparison of data obtained using ICP MS and electrochemical methods (after a proper chemical treatment) was also used for indication of Tl(III) presence and for proving that Tl(I) was not transferred into Tl(III) during analytical procedures.

  15. Distribution of four viruses in single and mixed infections within infected watermelon plants in Florida.

    PubMed

    Turechek, William W; Kousik, Chandrasekar S; Adkins, Scott

    2010-11-01

    Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV) and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in the past 5 years. Tissue-blot nucleic acid hybridization assays were developed for simple, high-throughput detection of these three viruses as well as Cucurbit yellow stunting disorder virus (CYSDV), which was first reported in Florida in 2008. To determine virus distribution within plants, we collected 80 entire plants just before or during the harvest period in a systematic sample, 20 each on 11 April, 18 April, 26 April, and 3 May 2007, from a fruiting commercial watermelon field near Immokalee, FL showing symptoms of infection by SqVYV, CuLCrV, and PRSV-W and, possibly, CYSDV. This was followed by a sampling of five plants collected at harvest showing symptoms of virus infection on 11 October 2007 in a different commercial planting located in Duette, FL. Tissue prints were made from cross sections of watermelon plants from the crowns through the tips at 0.6-m intervals on nylon membranes and nucleic acid hybridization assays were used for virus detection. Results from testing crown tissue showed that SqVYV, CuLCrV, and PRSV-W were present in ≈37, 44, and 54%, respectively, of the 80 plants collected over the four sampling dates from the first field. For individual vines diagnosed with SqVYV, the distribution of SqVYV in vine tissue decreased proportionately with distance from the crown. The probability of detecting SqVYV was 70% at the base of the vine compared with 23% at the tip of the vine. In contrast, CuLCrV tended to be more evenly distributed throughout the plant, with ≈10% higher probability of detection at the growing tip relative to the crown of the plant. The distribution of PRSV-W resembled that of SqVYV but with ≈20% higher probability of detection at the tip of the vine. Similar trends were

  16. Spatial Distribution and Sampling Plans for Grapevine Plant Canopy-Inhabiting Scaphoideus titanus (Hemiptera: Cicadellidae) Nymphs.

    PubMed

    Rigamonti, Ivo E; Brambilla, Carla; Colleoni, Emanuele; Jermini, Mauro; Trivellone, Valeria; Baumgärtner, Johann

    2016-04-01

    The paper deals with the study of the spatial distribution and the design of sampling plans for estimating nymph densities of the grape leafhopper Scaphoideus titanus Ball in vine plant canopies. In a reference vineyard sampled for model parameterization, leaf samples were repeatedly taken according to a multistage, stratified, random sampling procedure, and data were subjected to an ANOVA. There were no significant differences in density neither among the strata within the vineyard nor between the two strata with basal and apical leaves. The significant differences between densities on trunk and productive shoots led to the adoption of two-stage (leaves and plants) and three-stage (leaves, shoots, and plants) sampling plans for trunk shoots- and productive shoots-inhabiting individuals, respectively. The mean crowding to mean relationship used to analyze the nymphs spatial distribution revealed aggregated distributions. In both the enumerative and the sequential enumerative sampling plans, the number of leaves of trunk shoots, and of leaves and shoots of productive shoots, was kept constant while the number of plants varied. In additional vineyards data were collected and used to test the applicability of the distribution model and the sampling plans. The tests confirmed the applicability 1) of the mean crowding to mean regression model on the plant and leaf stages for representing trunk shoot-inhabiting distributions, and on the plant, shoot, and leaf stages for productive shoot-inhabiting nymphs, 2) of the enumerative sampling plan, and 3) of the sequential enumerative sampling plan. In general, sequential enumerative sampling was more cost efficient than enumerative sampling. PMID:26719593

  17. Spatial Distribution and Sampling Plans for Grapevine Plant Canopy-Inhabiting Scaphoideus titanus (Hemiptera: Cicadellidae) Nymphs.

    PubMed

    Rigamonti, Ivo E; Brambilla, Carla; Colleoni, Emanuele; Jermini, Mauro; Trivellone, Valeria; Baumgärtner, Johann

    2016-04-01

    The paper deals with the study of the spatial distribution and the design of sampling plans for estimating nymph densities of the grape leafhopper Scaphoideus titanus Ball in vine plant canopies. In a reference vineyard sampled for model parameterization, leaf samples were repeatedly taken according to a multistage, stratified, random sampling procedure, and data were subjected to an ANOVA. There were no significant differences in density neither among the strata within the vineyard nor between the two strata with basal and apical leaves. The significant differences between densities on trunk and productive shoots led to the adoption of two-stage (leaves and plants) and three-stage (leaves, shoots, and plants) sampling plans for trunk shoots- and productive shoots-inhabiting individuals, respectively. The mean crowding to mean relationship used to analyze the nymphs spatial distribution revealed aggregated distributions. In both the enumerative and the sequential enumerative sampling plans, the number of leaves of trunk shoots, and of leaves and shoots of productive shoots, was kept constant while the number of plants varied. In additional vineyards data were collected and used to test the applicability of the distribution model and the sampling plans. The tests confirmed the applicability 1) of the mean crowding to mean regression model on the plant and leaf stages for representing trunk shoot-inhabiting distributions, and on the plant, shoot, and leaf stages for productive shoot-inhabiting nymphs, 2) of the enumerative sampling plan, and 3) of the sequential enumerative sampling plan. In general, sequential enumerative sampling was more cost efficient than enumerative sampling.

  18. Remote sensing to inform Plant Functional Type (PFT) distributions in the Community Land Model

    NASA Astrophysics Data System (ADS)

    Kumar, J.; Langford, Z.; Yuan, F.; Hoffman, F. M.

    2014-12-01

    Sensitive Arctic ecosystems are vulnerable to change as warming climate impacts the hydrological, thermal, biogeochemical and plant physiological processes on the landscape, leading to geomorphic, biophysical and biogeochemical changes. In particular, Arctic vegetation is expected to exhibit significant shifts in community composition, phenology, distribution and productivity under a changing climate. Modeling of vegetation communities, often represented as Plant Functional Types (PFTs) in Earth System Models (ESMs), requires accurate characterization of their distributions on the landscape as input to ESMs. The unique spectral characteristics exhibited by vegetation can be sensed by remote sensing platforms and used to characterize and distinguish different vegetation types. In this study we employ multi-spectral remote sensing from WorldView--2 and LIDAR--derived digital elevation models to characterize the Arctic tundra vegetation communities near Barrow, Alaska. Using field vegetation surveys at a number of sites, we derived statistical relationships between vegetation distributions and spectral data, which were then employed to estimate the distributions of evergreen shrub, deciduous shrub, grass, sedge, forb, moss and lichen PFTs for the Barrow Environmental Observatory. Plant physiological parameters for these tundra-specific PFTs were implemented in the Community Land Model (CLM). We will present CLM results from simulations employing different distributions of these new PFTs, created using different subsets of remote sensing and in situ vegetation data, to test the sensitivity of the model to a range of predicted distributions.

  19. Leaf wax n-alkane distributions in and across modern plants: Implications for paleoecology and chemotaxonomy

    NASA Astrophysics Data System (ADS)

    Bush, Rosemary T.; McInerney, Francesca A.

    2013-09-01

    Long chain (C21 to C37) n-alkanes are among the most long-lived and widely utilized terrestrial plant biomarkers. Dozens of studies have examined the range and variation of n-alkane chain-length abundances in modern plants from around the world, and n-alkane distributions have been used for a variety of purposes in paleoclimatology and paleoecology as well as chemotaxonomy. However, most of the paleoecological applications of n-alkane distributions have been based on a narrow set of modern data that cannot address intra- and inter-plant variability. Here, we present the results of a study using trees from near Chicago, IL, USA, as well as a meta-analysis of published data on modern plant n-alkane distributions. First, we test the conformity of n-alkane distributions in mature leaves across the canopy of 38 individual plants from 24 species as well as across a single growing season and find no significant differences for either canopy position or time of leaf collection. Second, we compile 2093 observations from 86 sources, including the new data here, to examine the generalities of n-alkane parameters such as carbon preference index (CPI), average chain length (ACL), and chain-length ratios for different plant groups. We show that angiosperms generally produce more n-alkanes than do gymnosperms, supporting previous observations, and furthermore that CPI values show such variation in modern plants that it is prudent to discard the use of CPI as a quantitative indicator of n-alkane degradation in sediments. We also test the hypotheses that certain n-alkane chain lengths predominate in and therefore can be representative of particular plant groups, namely, C23 and C25 in Sphagnum mosses, C27 and C29 in woody plants, and C31 in graminoids (grasses). We find that chain-length distributions are highly variable within plant groups, such that chemotaxonomic distinctions between grasses and woody plants are difficult to make based on n-alkane abundances. In contrast

  20. Diversity distribution patterns of Chinese endemic seed plant species and their implications for conservation planning

    PubMed Central

    Huang, Jihong; Huang, Jianhua; Lu, Xinghui; Ma, Keping

    2016-01-01

    Endemism is an important concept in biogeography and biodiversity conservation. China is one of the richest countries in biodiversity, with very high levels of plant endemism. In this study, we analysed the distribution patterns of diversity, the degree of differentiation, and the endemicity of Chinese endemic seed plants using the floristic unit as a basic spatial analysis unit and 11 indices. The analysis was based on distribution data of 24,951 native seed plant species (excluding subspecies and varieties) and 12,980 Chinese endemic seed plant species, which were sourced from both specimen records and published references. The distribution patterns of Chinese endemic flora were generally consistent but disproportionate across China for diversity, degree of differentiation and endemicity. The South Hengduan Mountains Subregion had the highest values for all indices. At the regional level, both the Hengduan Mountains and the Central China regions were highest in diversity and degrees of differentiation. However, both the rate of local endemic to native species and the rate of local to Chinese endemic species were highest in the Taiwan Region and the South Taiwan Region. The Hengduan Mountains Region and the Central China Region are two key conservation priority areas for Chinese endemic seed plants. PMID:27658845

  1. Effects of amendments on the uptake and distribution of DDT in Cucurbita pepo ssp pepo plants.

    PubMed

    Whitfield Aslund, Melissa L; Lunney, Alissa I; Rutter, Allison; Zeeb, Barbara A

    2010-02-01

    The effects of soil amendments on the phytoextraction of summation operatorDDT (DDT + DDD + DDE) from soil ([ summation operatorDDT] approximately 1500 ng/g) by a pumpkin variety of Cucurbita pepo ssp pepo were tested and the patterns of summation operatorDDT storage throughout the plant shoot were examined. The soil amendments did not increase the total amount of summation operatorDDT extracted into plant shoots, but new information about summation operatorDDT distribution in the plants was obtained. As observed previously, the summation operatorDDT concentration in plant leaves (mean 290 ng/g) was significantly lower than in plant stems (mean 2600 ng/g). Further analysis revealed that summation operatorDDT composition was consistent throughout the plant shoot and that summation operatorDDT concentration in leaves and stems decreased exponentially as distance from the root increased, which was previously unknown. This new information about the patterns of summation operatorDDT uptake and translocation within pumpkin plants highlights the need for appropriate plant sampling strategies in future POPs phytoextraction research.

  2. Plant distributions along salinity and tidal gradients in Oregon tidal marshes

    EPA Science Inventory

    Accurately modeling climate change effects on tidal marshes in the Pacific Northwest requires understanding how plant assemblages and species are presently distributed along gradients of salinity and tidal inundation. We outline on-going field efforts by the EPA and USGS to dete...

  3. Industrial Electricity. In-Plant Distribution. Vocational Trade and Industrial Education.

    ERIC Educational Resources Information Center

    Teague, Cash; Pewewardy, Garner

    This curriculum guide, part of a series of industrial electricity curriculum guides, consists of materials for use in teaching a course on the in-plant distribution of electricity. Discussed in the introductory lessons are the National Electrical Code, power equipment, and blueprint reading. The next section, a series of units on branch-circuit…

  4. Description of the FORTRAN implementation of the spring small grains planting date distribution model

    NASA Technical Reports Server (NTRS)

    Artley, J. A. (Principal Investigator)

    1981-01-01

    The Hodges-Artley spring small grains planting date distribution model was coded in FORTRAN. The PLDRVR program, which implements the model, is described and a copy of the code is provided. The purpose, calling procedure, local variables, and input/output devices for each subroutine are explained to supplement the user's guide.

  5. Within-plant distribution of volatile compounds on the leaf surface of Flourensia cernua

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We are using Flourensia cernua as a shrub model to study the role of terpenes on intake by livestock. Two experiments were conducted to examine distribution of volatile chemicals within a plant in an effort to minimize sample variability. In Exp. 1, leaves (current year's growth) were collected from...

  6. Boll distribution and plant architecture of 14 commercial cultivars under five different irrigation regimes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a pressing need to identify and understand the effects of different irrigation regimes on the boll distribution, seed cotton yield, and plant architecture of commercial cultivars of cotton (Gossypium spp.). To identify the impact of different irrigation levels on the Texas High Plains 14 co...

  7. Effects of contrasting rooting distribution patterns on plant transpiration along a precipitation gradient

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding and predicting ecosystem functioning in water limited ecosystems requires a thorough assessment of the role plant root systems. Widespread ecological phenomena such as shrub encroachment may drastically change root distribution in the soil profile affecting the uptake of water and nutr...

  8. Spatial Distribution of Plant-Parasitic Nematodes in Semi-Arid Vitis vinifera Vineyards in Washington

    PubMed Central

    Howland, Amanda D.; Schreiner, R. Paul; Zasada, Inga A.

    2014-01-01

    The most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards are Meloidogyne hapla, Mesocriconema xenoplax, Pratylenchus spp., Xiphinema americanum, and Paratylenchus sp.; however, little is known about their distribution in the soil profile. The vertical and horizontal spatial distribution of plant-parasitic nematodes was determined in two Washington V. vinifera vineyards. Others variables measured in these vineyards included soil moisture content, fine root biomass, and root colonization by arbuscular mycorhizal fungi (AMF). Meloidogyne hapla and M. xenoplax were aggregated under irrigation emitters within the vine row and decreased with soil depth. Conversely, Pratylenchus spp. populations were primarily concentrated in vineyard alleyways and decreased with depth. Paratylenchus sp. and X. americanum were randomly distributed within the vineyards. Soil water content played a dominant role in the distribution of fine roots and plant-parasitic nematodes. Colonization of fine roots by AMF decreased directly under irrigation emitters; in addition, galled roots had lower levels of AMF colonization compared with healthy roots. These findings will help facilitate sampling and management decisions for plant-parasitic nematodes in Washington semi-arid vineyards. PMID:25580024

  9. Spatial Distribution of Plant-Parasitic Nematodes in Semi-Arid Vitis vinifera Vineyards in Washington.

    PubMed

    Howland, Amanda D; Schreiner, R Paul; Zasada, Inga A

    2014-12-01

    The most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards are Meloidogyne hapla, Mesocriconema xenoplax, Pratylenchus spp., Xiphinema americanum, and Paratylenchus sp.; however, little is known about their distribution in the soil profile. The vertical and horizontal spatial distribution of plant-parasitic nematodes was determined in two Washington V. vinifera vineyards. Others variables measured in these vineyards included soil moisture content, fine root biomass, and root colonization by arbuscular mycorhizal fungi (AMF). Meloidogyne hapla and M. xenoplax were aggregated under irrigation emitters within the vine row and decreased with soil depth. Conversely, Pratylenchus spp. populations were primarily concentrated in vineyard alleyways and decreased with depth. Paratylenchus sp. and X. americanum were randomly distributed within the vineyards. Soil water content played a dominant role in the distribution of fine roots and plant-parasitic nematodes. Colonization of fine roots by AMF decreased directly under irrigation emitters; in addition, galled roots had lower levels of AMF colonization compared with healthy roots. These findings will help facilitate sampling and management decisions for plant-parasitic nematodes in Washington semi-arid vineyards. PMID:25580024

  10. Distribution of vascular plants and macroalgae along salinity and elevation gradients in Oregon tidal marshes

    EPA Science Inventory

    Sea level rise due to global climate change may affect the spatial distribution of plants and macroalgae within tidal estuaries. We present preliminary results from on-going research in Oregon to determine how these potential abiotic drives correlate with the presence or absence...

  11. Spatial Distribution of Plant-Parasitic Nematodes in Semi-Arid Vitis vinifera Vineyards in Washington.

    PubMed

    Howland, Amanda D; Schreiner, R Paul; Zasada, Inga A

    2014-12-01

    The most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards are Meloidogyne hapla, Mesocriconema xenoplax, Pratylenchus spp., Xiphinema americanum, and Paratylenchus sp.; however, little is known about their distribution in the soil profile. The vertical and horizontal spatial distribution of plant-parasitic nematodes was determined in two Washington V. vinifera vineyards. Others variables measured in these vineyards included soil moisture content, fine root biomass, and root colonization by arbuscular mycorhizal fungi (AMF). Meloidogyne hapla and M. xenoplax were aggregated under irrigation emitters within the vine row and decreased with soil depth. Conversely, Pratylenchus spp. populations were primarily concentrated in vineyard alleyways and decreased with depth. Paratylenchus sp. and X. americanum were randomly distributed within the vineyards. Soil water content played a dominant role in the distribution of fine roots and plant-parasitic nematodes. Colonization of fine roots by AMF decreased directly under irrigation emitters; in addition, galled roots had lower levels of AMF colonization compared with healthy roots. These findings will help facilitate sampling and management decisions for plant-parasitic nematodes in Washington semi-arid vineyards.

  12. Predicting plant distribution in an heterogeneous Alpine landscape: does soil matter?

    NASA Astrophysics Data System (ADS)

    Buri, Aline; Cianfrani, Carmen; Pradervand, Jean-Nicolas; Guisan, Antoine

    2016-04-01

    Topographic and climatic factors are usually used to predict plant distribution because they are known to explain their presence or absence. Soil properties have been widely shown to influence plant growth and distributions. However, they are rarely taken into account as predictors of plant species distribution models (SDM) in an edaphically heterogeneous landscape. Or, when it happens, interpolation techniques are used to project soil factors in space. In heterogeneous landscape, such as in the Alps region, where soil properties change abruptly as a function of environmental conditions over short distances, interpolation techniques require a huge quantities of samples to be efficient. This is costly and time consuming, and bring more errors than predictive approach for an equivalent number of samples. In this study we aimed to assess whether soil proprieties may be generalized over entire mountainous geographic extents and can improve predictions of plant distributions over traditional topo-climatic predictors. First, we used a predictive approach to map two soil proprieties based on field measurements in the western Swiss Alps region; the soil pH and the ratio of stable isotopes 13C/12C (called δ13CSOM). We used ensemble forecasting techniques combining together several predictive algorithms to build models of the geographic variation in the values of both soil proprieties and projected them in the entire study area. As predictive factors, we employed very high resolution topo-climatic data. In a second step, output maps from the previous task were used as an input for vegetation regional models. We integrated the predicted soil proprieties to a set of basic topo-climatic predictors known to be important to model plants species. Then we modelled the distribution of 156 plant species inhabiting the study area. Finally, we compared the quality of the models having or not soil proprieties as predictors to evaluate their effect on the predictive power of our models

  13. DC-DC Converter Topology Assessment for Large Scale Distributed Photovoltaic Plant Architectures

    SciTech Connect

    Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Sabate, Juan A; Steigerwald, Robert L; Jiang, Yan; Essakiappan, Somasundaram

    2011-07-01

    Distributed photovoltaic (PV) plant architectures are emerging as a replacement for the classical central inverter based systems. However, power converters of smaller ratings may have a negative impact on system efficiency, reliability and cost. Therefore, it is necessary to design converters with very high efficiency and simpler topologies in order not to offset the benefits gained by using distributed PV systems. In this paper an evaluation of the selection criteria for dc-dc converters for distributed PV systems is performed; this evaluation includes efficiency, simplicity of design, reliability and cost. Based on this evaluation, recommendations can be made as to which class of converters is best fit for this application.

  14. Plant-soil distribution of potentially toxic elements in response to elevated atmospheric CO2.

    PubMed

    Duval, Benjamin D; Dijkstra, Paul; Natali, Susan M; Megonigal, J Patrick; Ketterer, Michael E; Drake, Bert G; Lerdau, Manuel T; Gordon, Gwyneth; Anbar, Ariel D; Hungate, Bruce A

    2011-04-01

    The distribution of contaminant elements within ecosystems is an environmental concern because of these elements' potential toxicity to animals and plants and their ability to hinder microbial ecosystem services. As with nutrients, contaminants are cycled within and through ecosystems. Elevated atmospheric CO2 generally increases plant productivity and alters nutrient element cycling, but whether CO2 causes similar effects on the cycling of contaminant elements is unknown. Here we show that 11 years of experimental CO2 enrichment in a sandy soil with low organic matter content causes plants to accumulate contaminants in plant biomass, with declines in the extractable contaminant element pools in surface soils. These results indicate that CO2 alters the distribution of contaminant elements in ecosystems, with plant element accumulation and declining soil availability both likely explained by the CO2 stimulation of plant biomass. Our results highlight the interdependence of element cycles and the importance of taking a broad view of the periodic table when the effects of global environmental change on ecosystem biogeochemistry are considered.

  15. Concentration and distribution of cobalt in higher plants: The use of micro-PIXE spectroscopy

    NASA Astrophysics Data System (ADS)

    Bakkaus, E.; Gouget, B.; Gallien, J.-P.; Khodja, H.; Carrot, F.; Morel, J. L.; Collins, R.

    2005-04-01

    Cobalt is not classified as an essential element for plants, however, it is usually described as "beneficial". This trace element can be a contaminant in soils due to agricultural additives or metal refineries. Certain plants species have the ability to extract metals (such as Co) from soils, thus, cleaning the environment. Therefore, knowledge of the physiological mechanisms of metal absorption is required to improve these phytoremediation technologies. Patterns of cobalt accumulation and storage were determined in tomato (Lycopersicon esculentum) and wheat (Triticum aestivum) species. Plants were grown in nutrient solutions, with different Co treatments, using controlled environmental conditions. The spatial distributions of K, Ca, Fe and Co in whole plants, and in leaf and stem sections, were examined by micro-PIXE. In conjunction, total Co concentrations were determined by ICP-MS. Micro-PIXE spectroscopy proved to be a convenient technique for indicating Co concentrations and distribution patterns in these plants. This knowledge aids in the identification of vegetal Co sequestration and, thus, helps to unravel how Co is transported in higher plants.

  16. Improved Predictions of the Geographic Distribution of Invasive Plants Using Climatic Niche Models.

    PubMed

    Ramírez-Albores, Jorge E; Bustamante, Ramiro O; Badano, Ernesto I

    2016-01-01

    Climatic niche models for invasive plants are usually constructed with occurrence records taken from literature and collections. Because these data neither discriminate among life-cycle stages of plants (adult or juvenile) nor the origin of individuals (naturally established or man-planted), the resulting models may mispredict the distribution ranges of these species. We propose that more accurate predictions could be obtained by modelling climatic niches with data of naturally established individuals, particularly with occurrence records of juvenile plants because this would restrict the predictions of models to those sites where climatic conditions allow the recruitment of the species. To test this proposal, we focused on the Peruvian peppertree (Schinus molle), a South American species that has largely invaded Mexico. Three climatic niche models were constructed for this species using high-resolution dataset gathered in the field. The first model included all occurrence records, irrespective of the life-cycle stage or origin of peppertrees (generalized niche model). The second model only included occurrence records of naturally established mature individuals (adult niche model), while the third model was constructed with occurrence records of naturally established juvenile plants (regeneration niche model). When models were compared, the generalized climatic niche model predicted the presence of peppertrees in sites located farther beyond the climatic thresholds that naturally established individuals can tolerate, suggesting that human activities influence the distribution of this invasive species. The adult and regeneration climatic niche models concurred in their predictions about the distribution of peppertrees, suggesting that naturally established adult trees only occur in sites where climatic conditions allow the recruitment of juvenile stages. These results support the proposal that climatic niches of invasive plants should be modelled with data of

  17. Improved Predictions of the Geographic Distribution of Invasive Plants Using Climatic Niche Models

    PubMed Central

    Ramírez-Albores, Jorge E.; Bustamante, Ramiro O.

    2016-01-01

    Climatic niche models for invasive plants are usually constructed with occurrence records taken from literature and collections. Because these data neither discriminate among life-cycle stages of plants (adult or juvenile) nor the origin of individuals (naturally established or man-planted), the resulting models may mispredict the distribution ranges of these species. We propose that more accurate predictions could be obtained by modelling climatic niches with data of naturally established individuals, particularly with occurrence records of juvenile plants because this would restrict the predictions of models to those sites where climatic conditions allow the recruitment of the species. To test this proposal, we focused on the Peruvian peppertree (Schinus molle), a South American species that has largely invaded Mexico. Three climatic niche models were constructed for this species using high-resolution dataset gathered in the field. The first model included all occurrence records, irrespective of the life-cycle stage or origin of peppertrees (generalized niche model). The second model only included occurrence records of naturally established mature individuals (adult niche model), while the third model was constructed with occurrence records of naturally established juvenile plants (regeneration niche model). When models were compared, the generalized climatic niche model predicted the presence of peppertrees in sites located farther beyond the climatic thresholds that naturally established individuals can tolerate, suggesting that human activities influence the distribution of this invasive species. The adult and regeneration climatic niche models concurred in their predictions about the distribution of peppertrees, suggesting that naturally established adult trees only occur in sites where climatic conditions allow the recruitment of juvenile stages. These results support the proposal that climatic niches of invasive plants should be modelled with data of

  18. Improved Predictions of the Geographic Distribution of Invasive Plants Using Climatic Niche Models.

    PubMed

    Ramírez-Albores, Jorge E; Bustamante, Ramiro O; Badano, Ernesto I

    2016-01-01

    Climatic niche models for invasive plants are usually constructed with occurrence records taken from literature and collections. Because these data neither discriminate among life-cycle stages of plants (adult or juvenile) nor the origin of individuals (naturally established or man-planted), the resulting models may mispredict the distribution ranges of these species. We propose that more accurate predictions could be obtained by modelling climatic niches with data of naturally established individuals, particularly with occurrence records of juvenile plants because this would restrict the predictions of models to those sites where climatic conditions allow the recruitment of the species. To test this proposal, we focused on the Peruvian peppertree (Schinus molle), a South American species that has largely invaded Mexico. Three climatic niche models were constructed for this species using high-resolution dataset gathered in the field. The first model included all occurrence records, irrespective of the life-cycle stage or origin of peppertrees (generalized niche model). The second model only included occurrence records of naturally established mature individuals (adult niche model), while the third model was constructed with occurrence records of naturally established juvenile plants (regeneration niche model). When models were compared, the generalized climatic niche model predicted the presence of peppertrees in sites located farther beyond the climatic thresholds that naturally established individuals can tolerate, suggesting that human activities influence the distribution of this invasive species. The adult and regeneration climatic niche models concurred in their predictions about the distribution of peppertrees, suggesting that naturally established adult trees only occur in sites where climatic conditions allow the recruitment of juvenile stages. These results support the proposal that climatic niches of invasive plants should be modelled with data of

  19. Analysis of new type III effectors from Xanthomonas uncovers XopB and XopS as suppressors of plant immunity.

    PubMed

    Schulze, Sebastian; Kay, Sabine; Büttner, Daniela; Egler, Monique; Eschen-Lippold, Lennart; Hause, Gerd; Krüger, Antje; Lee, Justin; Müller, Oliver; Scheel, Dierk; Szczesny, Robert; Thieme, Frank; Bonas, Ulla

    2012-09-01

    The pathogenicity of the Gram-negative plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria (Xcv) is dependent on type III effectors (T3Es) that are injected into plant cells by a type III secretion system and interfere with cellular processes to the benefit of the pathogen. In this study, we analyzed eight T3Es from Xcv strain 85-10, six of which were newly identified effectors. Genetic studies and protoplast expression assays revealed that XopB and XopS contribute to disease symptoms and bacterial growth, and suppress pathogen-associated molecular pattern (PAMP)-triggered plant defense gene expression. In addition, XopB inhibits cell death reactions induced by different T3Es, thus suppressing defense responses related to both PAMP-triggered immunity (PTI) and effector-triggered immunity (ETI). XopB localizes to the Golgi apparatus and cytoplasm of the plant cell and interferes with eukaryotic vesicle trafficking. Interestingly, a XopB point mutant derivative was defective in the suppression of ETI-related responses, but still interfered with vesicle trafficking and was only slightly affected with regard to the suppression of defense gene induction. This suggests that XopB-mediated suppression of PTI and ETI is dependent on different mechanisms that can be functionally separated. PMID:22738163

  20. Host-plant genotypic diversity mediates the distribution of an ecosystem engineer.

    PubMed

    Crawford, Kerri M; Crutsinger, Gregory M; Sanders, Nathan J

    2007-08-01

    Ecosystem engineers affect ecological communities by physically modifying the environment. Understanding the factors determining the distribution of engineers offers a powerful predictive tool for community ecology. In this study, we examine whether the goldenrod bunch gall midge (Rhopalomyia solidaginis) functions as an ecosystem engineer in an old-field ecosystem by altering the composition of arthropod species associated with a dominant host plant, Solidago altissima. We also examine the suite of factors that could affect the distribution and abundance of this ecosystem engineer. The presence of bunch galls increased species richness and altered the structure of associated arthropod communities. The best predictors of gall abundance were host-plant genotype and plot-level genotypic diversity. We found positive, nonadditive effects of genotypic diversity on gall abundance. Our results indicate that incorporating a genetic component in studies of ecosystem engineers can help predict their distribution and abundance, and ultimately their effects on biodiversity.

  1. Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

    SciTech Connect

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2005-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic expression, we first develop an analytic description and then extend that model along a single axis. Extrapolation

  2. The node, a hub for mineral nutrient distribution in graminaceous plants.

    PubMed

    Yamaji, Naoki; Ma, Jian Feng

    2014-09-01

    Mineral elements, including both essential and toxic elements, are delivered to different tissues after they are taken up from the roots, but the mechanism (or mechanisms) underlying the distribution remains poorly understood. In graminaceous plants, this distribution occurs in nodes, which have a complex, well-organized vascular system. A transfer of mineral elements between different vascular bundles is required, especially for preferential distribution to developing tissues that have low transpiration but high nutrient requirements. This intervascular transfer is mediated by various transporters localized at different cells in the node. In this opinion article, we propose four modes of distribution for different mineral elements: xylem-switch, phloem-tropic, phloem-kickback, and minimum-shift, based on specific molecular transport processes identified in the nodes mainly of rice (Oryza sativa). We also discuss the prospects for future studies on mineral nutrient distribution in the nodes.

  3. Predictive distribution modeling for rare Himalayan medicinal plant Berberis aristata DC.

    PubMed

    Ray, Rajasri; Gururaja, K V; Ramchandra, T V

    2011-11-01

    Predictive distribution modelling of Berberis aristata DC, a rare threatened plant with high medicinal values has been done with an aim to understand its potential distribution zones in Indian Himalayan region. Bioclimatic and topographic variables were used to develop the distribution model with the help of three different algorithms viz. Genetic Algorithm for Rule-set Production (GARP), Bioclim and Maximum entropy (MaxEnt). Maximum entropy has predicted wider potential distribution (10.36%) compared to GARP (4.63%) and Bioclim (2.44%). Validation confirms that these outputs are comparable to the present distribution pattern of the B. aristata. This exercise highlights that this species favours Western Himalaya. However, GARP and MaxEnt's prediction of Eastern Himalayan states (i. e. Arunachal Pradesh, Nagaland and Manipur) are also identified as potential occurrence places require further exploration.

  4. [Distribution of Mercury in Plants at Water-Level-Fluctuating Zone in the Three Gorges Reservoir].

    PubMed

    Liang, Li; Wang, Yong-min; Li, Xian-yuan; Tang, Zhen-ya; Zhang, Xiang; Zhang, Cheng; WANG, Ding-yong

    2015-11-01

    The mercury (Hg) distribution and storage in plants at water-level-fluctuating zone (WLFZ) in the Three Gorges Reservoir were investigated by analyzing the total mercury(THg) and methylmercury ( MeHg) levels in different parts of plants collected from three typical sites including Shibaozhai, Zhenxi and Hanfeng Lake in WLFZ. The results indicated that THg and MeHg concentrations in plants ranged from (1.62 ± 0.57) to (49.42 ± 3.93) μg x kg(-1) and from (15.27 ± 7.09) to (1 974.67 ± 946.10) ng x kg(-1), respectively. In addition, THg levels in different plant parts followed the trend: root > leaf > stem, and similar trend for MeHg was observed with the highest level in root. An obvious spatial distribution was also found with the THg and MeHg levels in plants in Hanfeng higher than those in the same plants in the other two sampling sites (Shibaozhai and Zhenxi), and there was a difference of THg and MeHg storage in plants in various attitudes. The corresponding THg and MeHg storages were 145.3, 166.4, 124.3 and 88.2 mg x hm(-2), and 1.9, 2.7, 3.6 and 3.2 mg x hm(-2) in 145-150, 150-160, 160-170 and 170-175 m attitudes. The accumulation ability of dominant plants in WLFZ for THg (bioaccumulation factor, BAF < 1) was weaker than that for MeHg (BAF > 1).

  5. Escherichia coli type III secretion system 2 (ETT2) is widely distributed in avian pathogenic Escherichia coli isolates from Eastern China.

    PubMed

    Wang, S; Liu, X; Xu, X; Zhao, Y; Yang, D; Han, X; Tian, M; Ding, C; Peng, D; Yu, S

    2016-10-01

    Pathogens utilize type III secretion systems to deliver effector proteins, which facilitate bacterial infections. The Escherichia coli type III secretion system 2 (ETT2) which plays a crucial role in bacterial virulence, is present in the majority of E. coli strains, although ETT2 has undergone widespread mutational attrition. We investigated the distribution and characteristics of ETT2 in avian pathogenic E. coli (APEC) isolates and identified five different ETT2 isoforms, including intact ETT2, in 57·6% (141/245) of the isolates. The ETT2 locus was present in the predominant APEC serotypes O78, O2 and O1. All of the ETT2 loci in the serotype O78 isolates were degenerate, whereas an intact ETT2 locus was mostly present in O1 and O2 serotype strains, which belong to phylogenetic groups B2 and D, respectively. Interestingly, a putative second type III secretion-associated locus (eip locus) was present only in the isolates with an intact ETT2. Moreover, ETT2 was more widely distributed in APEC isolates and exhibited more isoforms compared to ETT2 in human extraintestinal pathogenic E. coli, suggesting that APEC might be a potential risk to human health. However, there was no distinct correlation between ETT2 and other virulence factors in APEC.

  6. Final Report for DOE Project: Climate Effects on Plant Range Distributions and Community Structure of Pacific Northwest Prairies

    SciTech Connect

    Bridgham, Scott D.; Johnson, Bart

    2013-09-26

    Pacific Northwest (PNW) prairies are an imperiled ecosystem that contain a large number of plant species with high fidelity to this habitat. The few remaining high-quality PNW prairies harbor a number of sensitive, rare, and endangered plant species that may be further at-risk with climate change. Thus, PNW prairies are an excellent model system to examine how climate change will affect the distribution of native plant species in grassland sites. Our experimental objectives were to determine: (i) how climate change will affect the range distribution of native plant species; (ii) what life history stages are most sensitive to climate change in a group of key indicator native species; (iii) the robustness of current restoration techniques and suites of species to changing climate, and in particular, the relative competitiveness of native species versus exotic invasive species; and (iv) the effects of climate change on carbon and nutrient cycling and soil-microbial-plant feedbacks. We addressed these objectives by experimentally increasing temperature 2.5 to 3.0 ºC above ambient with overhead infrared lamps and increasing wet-season precipitation by 20% above ambient in three upland prairie sites in central-western Washington, central-western Oregon, and southwestern Oregon from fall 2010 through 2012. Additional precipitation was applied within 2 weeks of when it fell so precipitation intensity was increased, particularly during the winter rainy season but with minimal additions during the summer dry season. These three sites also represent a 520-km natural climate gradient of increasing degree of severity of Mediterranean climate from north to south. After removing the extant vegetation, we planted a diverse suite of 12 native species that have their northern range limit someplace within the PNW in each experimental plot. An additional 20 more wide-spread native species were also planted into each plot. We found that recruitment of plant species within their ranges

  7. Silicon modifies root anatomy, and uptake and subcellular distribution of cadmium in young maize plants

    PubMed Central

    Vaculík, Marek; Landberg, Tommy; Greger, Maria; Luxová, Miroslava; Stoláriková, Miroslava; Lux, Alexander

    2012-01-01

    Background and Aims Silicon (Si) has been shown to ameliorate the negative influence of cadmium (Cd) on plant growth and development. However, the mechanism of this phenomenon is not fully understood. Here we describe the effect of Si on growth, and uptake and subcellular distribution of Cd in maize plants in relation to the development of root tissues. Methods Young maize plants (Zea mays) were cultivated for 10 d hydroponically with 5 or 50 µm Cd and/or 5 mm Si. Growth parameters and the concentrations of Cd and Si were determined in root and shoot by atomic absorption spectrometry or inductively coupled plasma mass spectroscopy. The development of apoplasmic barriers (Casparian bands and suberin lamellae) and vascular tissues in roots were analysed, and the influence of Si on apoplasmic and symplasmic distribution of 109Cd applied at 34 nm was investigated between root and shoot. Key Results Si stimulated the growth of young maize plants exposed to Cd and influenced the development of Casparian bands and suberin lamellae as well as vascular tissues in root. Si did not affect the distribution of apoplasmic and symplasmic Cd in maize roots, but considerably decreased symplasmic and increased apoplasmic concentration of Cd in maize shoots. Conclusions Differences in Cd uptake of roots and shoots are probably related to the development of apoplasmic barriers and maturation of vascular tissues in roots. Alleviation of Cd toxicity by Si might be attributed to enhanced binding of Cd to the apoplasmic fraction in maize shoots. PMID:22455991

  8. Climate-driven C4 plant distributions in China: divergence in C4 taxa

    PubMed Central

    Wang, Renzhong; Ma, Linna

    2016-01-01

    There have been debates on the driving factors of C4 plant expansion, such as PCO2 decline in the late Micocene and warmer climate and precipitation at large-scale modern ecosystems. These disputes are mainly due to the lack of direct evidence and extensive data analysis. Here we use mass flora data to explore the driving factors of C4 distribution and divergent patterns for different C4 taxa at continental scale in China. The results display that it is mean annual climate variables driving C4 distribution at present-day vegetation. Mean annual temperature is the critical restriction of total C4 plants and the precipitation gradients seem to have much less impact. Grass and sedge C4 plants are largely restricted to mean annual temperature and precipitation respectively, while Chenopod C4 plants are strongly restricted by aridity in China. Separate regression analysis can succeed to detect divergences of climate distribution patterns of C4 taxa at global scale. PMID:27302686

  9. Areas of Increasing Agricultural Abandonment Overlap the Distribution of Previously Common, Currently Threatened Plant Species

    PubMed Central

    Osawa, Takeshi; Kohyama, Kazunori; Mitsuhashi, Hiromune

    2013-01-01

    Human-driven land-use changes increasingly threaten biodiversity. In agricultural ecosystems, abandonment of former farmlands constitutes a major land-use shift. We examined the relationships between areas in which agriculture has been abandoned and the distribution records of threatened plant species across Japan. We selected 23 plant species that are currently identified as threatened but were previously common in the country as indicators of threatened plant species. The areas of abandoned farmlands within the distribution ranges of the indicator species were significantly larger than the proportion of abandoned farmland area across the whole country. Also, abandoned farmland areas were positively correlated with the occurrence of indicator species. Therefore, sections of agricultural landscape that are increasingly becoming abandoned and the distribution ranges of indicator species overlapped. These results suggest that abandoned farmland areas contain degraded or preferred habitats of threatened plant species. We propose that areas experiencing increased abandonment of farmland can be divided into at least two categories: those that threaten the existence of threatened species and those that provide habitats for these threatened species. PMID:24260328

  10. [Relationship between ephemeral plants distribution and soil moisture on longitudinal dune surface in Gurbantonggut desert].

    PubMed

    Wang, Xueqin; Jiang, Jin; Lei, Jiaqiang; Zhao, Congju

    2004-04-01

    Ephemeral plant is a particular group of desert flora only distributed in northern Xinjiang, China. In this study, field surveys of vegetation and soil moisture were conducted in the southern area of the Gurbantonggut desert from March to August 2002. The species number, coverage and growth of ephemerals and soil moisture were measured in 7 quadrats at different geomorphic positions on the longitudinal dune surface. The results showed that soil moisture in a depth of 0-30 cm affected ephemeral plants distribution significantly. In early spring, the soil moisture was 4.62% on the intredune, 3.98% on the plinth, and 2.01% on the crest. Consequently, the average coverage of ephemeral plants reached 51.8%, 38.2% and 4.4%, respectively. The existence of ephemeral plants distribution influenced soil moisture as well. In later May, there was an increase of surface soil moisture from the interdune to the crest. The soil moisture was 1.00% on the intredune, 1.90% on the plinth, and 2.45% on the crest.

  11. Visualizing metabolite distribution and enzymatic conversion in plant tissues by desorption electrospray ionization mass spectrometry imaging.

    PubMed

    Li, Bin; Knudsen, Camilla; Hansen, Natascha Krahl; Jørgensen, Kirsten; Kannangara, Rubini; Bak, Søren; Takos, Adam; Rook, Fred; Hansen, Steen H; Møller, Birger Lindberg; Janfelt, Christian; Bjarnholt, Nanna

    2013-06-01

    In comparison with the technology platforms developed to localize transcripts and proteins, imaging tools for visualization of metabolite distributions in plant tissues are less well developed and lack versatility. This hampers our understanding of plant metabolism and dynamics. In this study, we demonstrate that desorption electrospray ionization mass spectrometry imaging (DESI-MSI) of tissue imprints on porous Teflon may be used to accurately image the distribution of even labile plant metabolites such as hydroxynitrile glucosides, which normally undergo enzymatic hydrolysis by specific β-glucosidases upon cell disruption. This fast and simple sample preparation resulted in no substantial differences in the distribution and ratios of all hydroxynitrile glucosides between leaves from wild-type Lotus japonicus and a β-glucosidase mutant plant that lacks the ability to hydrolyze certain hydroxynitrile glucosides. In wild-type, the enzymatic conversion of hydroxynitrile glucosides and the concomitant release of glucose were easily visualized when a restricted area of the leaf tissue was damaged prior to sample preparation. The gene encoding the first enzyme in hydroxynitrile glucoside biosynthesis in L. japonicus leaves, CYP79D3, was found to be highly expressed during the early stages of leaf development, and the hydroxynitrile glucoside distribution in mature leaves reflected this early expression pattern. The utility of direct DESI-MSI of plant tissue was demonstrated using cryo-sections of cassava (Manihot esculenta) tubers. The hydroxynitrile glucoside levels were highest in the outer cell layers, as verified by LC-MS analyses. The unexpected discovery of a hydroxynitrile-derived di-glycoside shows the potential of DESI-MSI to discover and guide investigations into new metabolic routes.

  12. Cadmium distribution within corn plants as a function of cadmium loading of the soil

    SciTech Connect

    Re, M.; Garagiola, M.G.; Crovato, E.

    1983-02-01

    Corn is a widespread crop in some industrialized areas of Northern Italy and Europe where it serves for both animal and human nutrition. In the present paper we examined the distribution of Cd within corn plants grown under both hydroponic and field conditions. The results obtained show that Cd accumulation by different plant tissues may reach saturation without signs of phytotoxicity. Thus cadmium pollution can go undetected even when corn tissue is responsible for the entry of the metal into the food chain. Implications for human and animal nutrition are discussed.

  13. Distribution of photosynthetically fixed /sup 14/C in perennial plant species of the northern Mojave Desert

    SciTech Connect

    Wallace, A.; Cha, J.W.; Romney, E.M.

    1980-01-01

    The distribution of photosynthate among plant parts subsequent to its production is needed to fully understand behavior of vegetation in any ecosystem. The present study, undertaken primarily to obtain information on transport of assimilates into roots of desert vegetation, was conducted in the northern Mojave Desert, where the mean annual rainfall is about 10 cm. Shoots of Ambrosia dumosa (A. Gray) Payne plants were exposed to /sup 14/CO/sub 2/ in 1971, and the distribution of /sup 14/C in roots, stems, and leaves was subsequently measured at 1 week, 2 months, and 5 months. Only about 12 percent of the /sup 14/C photosynthate was stored in the root. Much of that stored in stems was available for new leaf growth. Photosynthate was labeled with /sup 14/C for 24 plants representing eight species in 1972. Results showed that after 127 days the mean percentage of /sup 14/C in roots as compared with the estimate of that originally fixed was 11.8; the percentage in stems was 43.8. To check the validity of the /sup 14/C data, root growth of eight perennial desert plants grown in the glasshouse was followed as plants increased in size. The mean percent of the whole plant that was root for eight species was 17.7 percent. The mean proportion of the increase in plant weights that went below ground for the eight species was 19.5 percent. This value is higher than the fraction of /sup 14/C found below ground, and therefore the /sup 14/C technique underestimates the movement of C to roots. Results of an experiment designed to test the value of the /sup 14/C-pulse technique for determining current root growth for some perennial species from the desert indicated that the transition part of roots where root growth continued after exposure to /sup 14/C was highly labeled. Old growth contained less /sup 14/C than new growth.

  14. Spatial Distribution of Adults of Triozoida limbata (Enderlein) (Hemiptera: Triozidae) in Guava Plants.

    PubMed

    Marcelino, M C S; Barbosa, J C

    2016-04-01

    The psyllid Triozoida limbata (Enderlein) (Hemiptera: Triozidae) is a major pest in guava, feeding primarily on new shoots. Despite its importance, there are no studies on the spatial distribution of T. limbata on guava. Such studies are needed to establish sequential sampling plans for decision making in pest control. Thus, an experiment was carried out in a 9-year-old commercial guava orchard divided into 100 sampling units or plots. Double-sided yellow sticky traps were placed on one plant per plot (sample unit) to capture and monitor T. limbata adults from April 2011 to May 2012. To determine the insect distribution in the area, we calculated the variance-to-mean ratio index (I), the Morisita index (I δ ), Green's coefficient (Cx), and the k exponent of the negative binomial distribution. Most of the samples showed that the adults had a moderate to highly aggregated distribution. Statistical models were also used to study the pest spatial distribution by fitting the number of adults captured to the Poisson and negative binomial distributions. The negative binomial distribution model best fitted the data of the number of adult psyllids captured by the traps, which is consistent with an aggregated distribution. PMID:26597967

  15. Spatial Distribution of Adults of Triozoida limbata (Enderlein) (Hemiptera: Triozidae) in Guava Plants.

    PubMed

    Marcelino, M C S; Barbosa, J C

    2016-04-01

    The psyllid Triozoida limbata (Enderlein) (Hemiptera: Triozidae) is a major pest in guava, feeding primarily on new shoots. Despite its importance, there are no studies on the spatial distribution of T. limbata on guava. Such studies are needed to establish sequential sampling plans for decision making in pest control. Thus, an experiment was carried out in a 9-year-old commercial guava orchard divided into 100 sampling units or plots. Double-sided yellow sticky traps were placed on one plant per plot (sample unit) to capture and monitor T. limbata adults from April 2011 to May 2012. To determine the insect distribution in the area, we calculated the variance-to-mean ratio index (I), the Morisita index (I δ ), Green's coefficient (Cx), and the k exponent of the negative binomial distribution. Most of the samples showed that the adults had a moderate to highly aggregated distribution. Statistical models were also used to study the pest spatial distribution by fitting the number of adults captured to the Poisson and negative binomial distributions. The negative binomial distribution model best fitted the data of the number of adult psyllids captured by the traps, which is consistent with an aggregated distribution.

  16. Dominant and novel clades of Candidatus Accumulibacter phosphatis in 18 globally distributed full-scale wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Mao, Yanping; Graham, David W.; Tamaki, Hideyuki; Zhang, Tong

    2015-07-01

    Here we employed quantitative real-time PCR (qPCR) assays for polyphosphate kinase 1 (ppk1) and 16S rRNA genes to assess relative abundances of dominant clades of Candidatus Accumulibacter phosphatis (referred to Accumulibacter) in 18 globally distributed full-scale wastewater treatment plants (WWTPs) from six countries. Accumulibacter were not only detected in the 6 WWTPs performing biological phosphorus removal, but also inhabited in the other 11 WWTPs employing conventional activated sludge (AS) with abundances ranging from 0.02% to 7.0%. Among the AS samples, clades IIC and IID were found to be dominant among the five Accumulibacter clades. The relative abundance of each clade in the Accumulibacter lineage significantly correlated (p < 0.05) with the influent total phosphorus and chemical oxygen demand instead of geographical factors (e.g. latitude), which showed that the local wastewater characteristics and WWTPs configurations could be more significant to determine the proliferation of Accumulibacter clades in full-scale WWTPs rather than the geographical location. Moreover, two novel Accumulibacter clades (IIH and II-I) which had not been previously detected were discovered in two enhanced biological phosphorus removal (EBPR) WWTPs. The results deepened our understanding of the Accumulibacter diversity in environmental samples.

  17. Dominant and novel clades of Candidatus Accumulibacter phosphatis in 18 globally distributed full-scale wastewater treatment plants

    PubMed Central

    Mao, Yanping; Graham, David W.; Tamaki, Hideyuki; Zhang, Tong

    2015-01-01

    Here we employed quantitative real-time PCR (qPCR) assays for polyphosphate kinase 1 (ppk1) and 16S rRNA genes to assess relative abundances of dominant clades of Candidatus Accumulibacter phosphatis (referred to Accumulibacter) in 18 globally distributed full-scale wastewater treatment plants (WWTPs) from six countries. Accumulibacter were not only detected in the 6 WWTPs performing biological phosphorus removal, but also inhabited in the other 11 WWTPs employing conventional activated sludge (AS) with abundances ranging from 0.02% to 7.0%. Among the AS samples, clades IIC and IID were found to be dominant among the five Accumulibacter clades. The relative abundance of each clade in the Accumulibacter lineage significantly correlated (p < 0.05) with the influent total phosphorus and chemical oxygen demand instead of geographical factors (e.g. latitude), which showed that the local wastewater characteristics and WWTPs configurations could be more significant to determine the proliferation of Accumulibacter clades in full-scale WWTPs rather than the geographical location. Moreover, two novel Accumulibacter clades (IIH and II-I) which had not been previously detected were discovered in two enhanced biological phosphorus removal (EBPR) WWTPs. The results deepened our understanding of the Accumulibacter diversity in environmental samples. PMID:26138542

  18. Dominant and novel clades of Candidatus Accumulibacter phosphatis in 18 globally distributed full-scale wastewater treatment plants.

    PubMed

    Mao, Yanping; Graham, David W; Tamaki, Hideyuki; Zhang, Tong

    2015-01-01

    Here we employed quantitative real-time PCR (qPCR) assays for polyphosphate kinase 1 (ppk1) and 16S rRNA genes to assess relative abundances of dominant clades of Candidatus Accumulibacter phosphatis (referred to Accumulibacter) in 18 globally distributed full-scale wastewater treatment plants (WWTPs) from six countries. Accumulibacter were not only detected in the 6 WWTPs performing biological phosphorus removal, but also inhabited in the other 11 WWTPs employing conventional activated sludge (AS) with abundances ranging from 0.02% to 7.0%. Among the AS samples, clades IIC and IID were found to be dominant among the five Accumulibacter clades. The relative abundance of each clade in the Accumulibacter lineage significantly correlated (p < 0.05) with the influent total phosphorus and chemical oxygen demand instead of geographical factors (e.g. latitude), which showed that the local wastewater characteristics and WWTPs configurations could be more significant to determine the proliferation of Accumulibacter clades in full-scale WWTPs rather than the geographical location. Moreover, two novel Accumulibacter clades (IIH and II-I) which had not been previously detected were discovered in two enhanced biological phosphorus removal (EBPR) WWTPs. The results deepened our understanding of the Accumulibacter diversity in environmental samples. PMID:26138542

  19. Accumulation of contaminants of emerging concern in food crops-part 2: Plant distribution.

    PubMed

    Hyland, Katherine C; Blaine, Andrea C; Higgins, Christopher P

    2015-10-01

    Arid agricultural regions often turn to using treated wastewater (reclaimed water) to irrigate food crops. Concerns arise, however, when considering the potential for persistent contaminants of emerging concern to accumulate into plants intended for human consumption. The present study examined the accumulation of a suite of 9 contaminants of emerging concern into 2 representative food crops, lettuce and strawberry, following uptake via the roots and subsequent distribution to other plant tissues. Calculating accumulation metrics (concentration factors) allowed for comparison of the compartmental affinity of each chemical for each plant tissue compartment. The root concentration factor was found to exhibit a positive linear correlation with the pH-adjusted octanol-water partition coefficient (DOW ) for the target contaminants of emerging concern. Coupled with the concentration-dependent accumulation observed in the roots, this result implies that accumulation of these contaminants of emerging concern into plant roots is driven by passive partitioning. Of the contaminants of emerging concern examined, nonionizable contaminants, such as triclocarban, carbamazepine, and organophosphate flame retardants displayed the greatest potential for translocation from the roots to above-ground plant compartments. In particular, the organophosphate flame retardants displayed increasing affinity for shoots and fruits with decreasing size/octanol-water partition coefficient (KOW ). Cationic diphenhydramine and anionic sulfamethoxazole, once transported to the shoots of the strawberry plant, demonstrated the greatest potential of the contaminants examined to be then carried to the edible fruit portion. PMID:25988579

  20. Intelligent Monitoring System with High Temperature Distributed Fiberoptic Sensor for Power Plant Combustion Processes

    SciTech Connect

    Kwang Y. Lee; Stuart S. Yin; Andre Boehman

    2006-09-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we have set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors have been completed. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we have investigated a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. Given a set of empirical data with no analytic expression, we first developed an analytic description and then extended that model along a single axis.

  1. INTELLIGENT MONITORING SYSTEM WITH HIGH TEMPERATURE DISTRIBUTED FIBEROPTIC SENSOR FOR POWER PLANT COMBUSTION PROCESSES

    SciTech Connect

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2004-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, improvement was made on the performance of in-fiber grating fabricated in single crystal sapphire fibers, test was performed on the grating performance of single crystal sapphire fiber with new fabrication methods, and the fabricated grating was applied to high temperature sensor. Under Task 2, models obtained from 3-D modeling of the Demonstration Boiler were used to study relationships between temperature and NOx, as the multi-dimensionality of such systems are most comparable with real-life boiler systems. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic

  2. Genes Encoding Plant-Specific Class III Peroxidases Are Responsible for Increased Cold Tolerance of the brassinosteroid-insensitive 1 Mutant

    PubMed Central

    Kim, Beg Hab; Kim, Sun Young; Nam, Kyoung Hee

    2012-01-01

    We previously reported that one of the brassinosteroid-insensitive mutants, bri1-9, showed increased cold tolerance compared with both wild type and BRI1-overexpressing transgenic plants, despite its severe growth retardation. This increased tolerance in bri1-9 resulted from the constitutively high expression of stress-inducible genes under normal conditions. In this report, we focused on the genes encoding class III plant peroxidases (AtPrxs) because we found that, compared with wild type, bri1-9 plants contain higher levels of reactive oxygen species (ROS) that are not involved with the activation of NADPH oxidase and show an increased level of expression of a subset of genes encoding class III plant peroxidases. Treatment with a peroxidase inhibitor, salicylhydroxamic acid (SHAM), led to the reduction of cold resistance in bri1-9. Among 73 genes that encode AtPrxs in Arabidopsis, we selected four (AtPrx1, AtPrx22, AtPrx39, and AtPrx69) for further functional analyses in response to cold temperatures. T-DNA insertional knockout mutants showed increased sensitivity to cold stress as measured by leaf damage and ion leakage. In contrast, the overexpression of AtPrx22, AtPrx39, and AtPrx69 increased cold tolerance in the BRI1-GFP plants. Taken together, these results indicate that the appropriate expression of a particular subset of AtPrx genes and the resulting higher levels of ROS production are required for the cold tolerance. PMID:23180292

  3. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    DOEpatents

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  4. Risk analysis of highly combustible gas storage, supply, and distribution systems in PWR plants

    SciTech Connect

    Simion, G.P.; VanHorn, R.L.; Smith, C.L.; Bickel, J.H.; Sattison, M.B.; Bulmahn, K.D.

    1993-06-01

    This report presents the evaluation of the potential safety concerns for pressurized water reactors (PWRs) identified in Generic Safety Issue 106, Piping and the Use of Highly Combustible Gases in Vital Areas. A Westinghouse four-loop PWR plant was analyzed for the risk due to the use of combustible gases (predominantly hydrogen) within the plant. The analysis evaluated an actual hydrogen distribution configuration and conducted several sensitivity studies to determine the potential variability among PWRs. The sensitivity studies were based on hydrogen and safety-related equipment configurations observed at other PWRs within the United States. Several options for improving the hydrogen distribution system design were identified and evaluated for their effect on risk and core damage frequency. A cost/benefit analysis was performed to determine whether alternatives considered were justifiable based on the safety improvement and economics of each possible improvement.

  5. Silica distribution in various bamboos species and its effects on plant growth

    NASA Astrophysics Data System (ADS)

    Collin, B.; Meunier, J.; Keller, C.; Doelsch, E.; Panfili, F.

    2010-12-01

    Bamboos are distributed throughout the world’s temperate, tropical and subtropical regions. They are widely used in industry, as fresh edible shoots, paper maker, building and even in medicine. Bamboos also play multiple ecologic functions such as soil and water conservation and erosion control. Bamboos have generally high silicon (Si) content. Silicon is known to have beneficial effects on plants and alleviate various stresses. The aim of this study is to quantify the Si uptake and distribution in various bamboos species and to investigate the effects of Si on the plant growth. Two complementary studies were carried out, one under natural conditions and one under controlled conditions. First of all, we performed an inventory of Si tissue content in 16 bamboos species growing in a non-polluted tropical soil at the Reunion Island (France, Indian ocean). We determined Si content in leaf and in stem tissues sampled at several heights for each plant. One of these species Gigantocloa sp « Malay Dwarf » was grown for 3 months in nutrient solution at five Si concentrations (0, 0.25, 0.75, 1.15, 1.5 mM Si). Silica deposition was examined in leaves using a cryo-SEM equipped with EDS. The Si concentration varies significantly between species, depending on rhizome morphology. Bamboos having leptomorph rhizomes show significantly higher leaf and stem Si content than that of species having pachymorph rhizomes. The distribution of Si in the plant has the same trends for all species. Leaves are the most concentrated organs (10.9 %), and within the stem Si concentration significantly increases from the bottom (0.32%) to the top of the plant (2.1%). Plant Si content increases with the Si supply. Leaves of Gigantocloa sp « Malay Dwarf » accumulate 15.2 % of Si under natural conditions and up to 24 % when exposed to the highest Si treatment. Unlike previous studies, our experiment shows that the concentration of Si had no significant effect on nutrient uptake and biomass

  6. [Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

    PubMed

    Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

    2016-02-15

    Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower.

  7. [Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

    PubMed

    Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

    2016-02-15

    Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower. PMID:27363131

  8. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers

    SciTech Connect

    Toman, G.; Gazdzinski, R.

    1994-05-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in power and distribution transformers important to license renewal in commercial nuclear power plants. The intent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  9. [The distribution and viability changes of the Agrobacteria in the vacuum infiltrated plants of Chinese cabbage].

    PubMed

    Xu, Heng-Jian; Liu, Fan; Wang, Xiu-Feng; Zhao, Hong

    2005-08-01

    To understand further the mechanism of agrobacteria transformation by vacuum infiltration, the distribution and viability changes of the agrobacteria in infiltrated Chinese cabbage( B. rapa ssp. chinesis) plants were investigated by histochemical staining and bacteria plating techniques. Results revealed that there were different quantities of Agrobacteria in different organs, among which the most quantity occurred in flowers, especially in ovules. The Agrobacteria lied in the space between cells and concentrated in the vascular bundle no matter the type of the organs examined. The CFUs (colony forming unit) of the Agrobacteria derived from the flowers were always the most in every experiment. The viabilities of the agrobacteria in the plants declined dramatically along with the elongation of the time after plant infiltration in all organs, but there were still 10(3) CFUs per gram fresh tissue in the flowers after 15 days of infiltration. These results may explain the fact that the ovules were the targets for the Agrobacteria mediated vacuum infiltration transformation.

  10. Analysis of Nuclear Mitochondrial DNA Segments of Nine Plant Species: Size, Distribution, and Insertion Loci

    PubMed Central

    Ko, Young-Joon

    2016-01-01

    Nuclear mitochondrial DNA segment (Numt) insertion describes a well-known phenomenon of mitochondrial DNA transfer into a eukaryotic nuclear genome. However, it has not been well understood, especially in plants. Numt insertion patterns vary from species to species in different kingdoms. In this study, the patterns were surveyed in nine plant species, and we found some tip-offs. First, when the mitochondrial genome size is relatively large, the portion of the longer Numt is also larger than the short one. Second, the whole genome duplication event increases the ratio of the shorter Numt portion in the size distribution. Third, Numt insertions are enriched in exon regions. This analysis may be helpful for understanding plant evolution. PMID:27729838

  11. Spatial distribution of iron oxidation in the aerobic cells of the Wheal Jane Pilot Passive Treatment Plant.

    PubMed

    Hall, G H; Puhlmann, T

    2005-02-01

    The wetland cells of the Wheal Jane Pilot Passive Treatment Plant (PPTP) were designed to promote aerobic oxidation and precipitation of iron which could exceed a concentration of 100 mg l-1 in the raw mine water. The largest investment of land area was to the wetland (also called aerobic) cells and it was important to understand the processes of oxidation and precipitation of iron so that the performance of this part of the pilot passive treatment plant (PPTP) could be managed efficiently. The results of a high-resolution sampling programme on the distribution of Fe(II) within the first wetland cell of each treatment system are described. Comparison of inflow and outflow concentrations of iron adequately described the performance of the lime-dosed (LD) system. However, precipitation of iron in the anoxic limestone drain (ALD) and lime-free systems (LFS) was more efficient. On average, about 90% of the iron present in the inflow was removed using only 50% and 33% of the first aerobic cells of the ALD and LFS systems, respectively. As the concentration of iron approached 20 mg l-1, the rate of oxidation slowed considerably. This was probably due to be due to low pH levels caused by hydrolysis of Fe(III). With the introduction of passive pH control mechanisms, there was capacity to increase the volume of mine water treated by the ALD and LDS systems by 10 and 15 times, respectively, but it is uncertain as to whether or not other aspects of the passive treatment system would have sufficient capacity to deal with the increased volumes of mine water. PMID:15680628

  12. Highly tunable heterogeneously integrated III-V on silicon sampled-grating distributed Bragg reflector lasers operating in the O-band.

    PubMed

    Duprez, Helene; Jany, Christophe; Seassal, Christian; Ben Bakir, Badhise

    2016-09-01

    We report on the design, fabrication and performance of the first hetero-integrated III-V on silicon sampled-grating distributed Bragg reflector lasers (SGDBR) operating in the O-band and based on direct bonding and adiabatic coupling. Two devices with different geometric parameters are presented both showing an output power in the Si waveguide as high as 7.5 mW and a continuous tuning range of 27 and 35 nm respectively with a side mode suppression ration higher than 35 dB. PMID:27607693

  13. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 3. Appendices. Part 2

    SciTech Connect

    Lee, S. K.

    1983-12-31

    The auxiliary heat transport systems of the Carrisa Plains Solar Power Plant (CPSPP) comprise facilities which are used to support plant operation and provide plant safety and maintenance. The facilities are the sodium purification system, argon cover gas system, sodium receiving and filling system, sodium-water reaction product receiving system, and safety and maintenance equipment. The functions of the facilities of the auxiliary system are described. Design requirements are established based on plant operating parameters. Descriptions are given on the system which will be adequate to perform the function and satisfy the requirements. Valve and equipment lists are included in the appendix.

  14. Speciation and mass distribution of mercury in a bituminous coal-fired power plant

    NASA Astrophysics Data System (ADS)

    Lee, Sung Jun; Seo, Yong-Chil; Jang, Ha-Na; Park, Kyu-Shik; Baek, Jeom-In; An, Hi-Soo; Song, Kwang-Chul

    Characterization and mass balance of mercury in a coal-fired power plant were carried out in a 500 MW, bituminous coal consuming electric utility boiler. This facility is equipped with a cold-side electrostatic precipitator (ESP) and a wet flue gas desulfurization (FGD) in series as air pollution control devices (APCDs). Mercury sampling points were selected at both the up and down streams of the ESP and outlet of the FGD, which is at stack. Two different types of sampling methods were employed, one is the Ontario Hydro (OH) method (ASTM D6784) and the other is US EPA101A. Various samples were collected from the coal-fired power plant such as fuel coals, fly ash in hopper, lime/lime stone, gypsum, and effluent water from FGD. These samples were analyzed by US EPA 7470A and 7471A to understand the behavior and mass balance of mercury in the process of a coal-fired power plant. There are no significant differences between the two sampling methods, but the OH method seems to have more advantages for Hg sampling from a coal-fired power plant because mercury speciation is quite an important factor to estimate the mercury emission and control efficiency from combustion flue gas. Approximate Hg mass balance could be obtained from various samples in the study; however, a series of long-term and comprehensive study is required to evaluate the reliable Hg mass distribution and behavior in a coal-fired power plant.

  15. Distribution of Vitamin E, squalene, epicatechin, and rutin in common buckwheat plants (Fagopyrum esculentum Moench).

    PubMed

    Kalinova, Jana; Triska, Jan; Vrchotova, Nadezda

    2006-07-26

    Buckwheat leaves and young parts of the plant are consumed in some countries as a vegetable. Green flour, obtained by milling of the dried plants, is used as a natural food colorant. The distribution of vitamin E, squalene, epicatechin, and rutin (as the most important antioxidants) within buckwheat plants, as well as changes of their content within leaves during the growing season, were determined by GC-MS and HPLC analyses. alpha-Tocopherol was found as the main component of vitamin E in all parts of the plant; epicatechin and squalene were also detected. For the use of buckwheat as an antioxidant source in the human diet, the most suitable part of the plants seems to be the leaves and the flowers at the stage of full flowering due to the considerable amounts of rutin and epicatechin. alpha-Tocopherol content correlates positively with temperature, drought, and duration of solar radiation. Certain differences appear among varieties of buckwheat, especially in their squalene and rutin contents.

  16. Relationship between Particle Size Distribution of Low-Rank Pulverized Coal and Power Plant Performance

    DOE PAGES

    Ganguli, Rajive; Bandopadhyay, Sukumar

    2012-01-01

    Tmore » he impact of particle size distribution (PSD) of pulverized, low rank high volatile content Alaska coal on combustion related power plant performance was studied in a series of field scale tests. Performance was gauged through efficiency (ratio of megawatt generated to energy consumed as coal), emissions (SO 2 , NO x , CO), and carbon content of ash (fly ash and bottom ash).he study revealed that the tested coal could be burned at a grind as coarse as 50% passing 76 microns, with no deleterious impact on power generation and emissions.he PSD’s tested in this study were in the range of 41 to 81 percent passing 76 microns.here was negligible correlation between PSD and the followings factors: efficiency, SO 2 , NO x , and CO. Additionally, two tests where stack mercury (Hg) data was collected, did not demonstrate any real difference in Hg emissions with PSD.he results from the field tests positively impacts pulverized coal power plants that burn low rank high volatile content coals (such as Powder River Basin coal).hese plants can potentially reduce in-plant load by grinding the coal less (without impacting plant performance on emissions and efficiency) and thereby, increasing their marketability.« less

  17. A systematic approach to document cyclotide distribution in plant species from genomic, transcriptomic, and peptidomic analysis.

    PubMed

    Gerlach, Samantha L; Göransson, Ulf; Kaas, Quentin; Craik, David J; Mondal, Debasis; Gruber, Christian W

    2013-09-01

    Cyclotides are a large family of plant peptides characterized by their cyclic cystine knot composed of a circular backbone and three disulfide bonds that impart exceptional stability. They, and several acyclic variants, have been isolated from plants within the Rubiaceae, Violaceae, Cucurbitaceae, Fabaceae, Solanaceae, and Poaceae families. A variety of chemical and genetic approaches have been applied for the discovery and characterization of cyclotides. As investigations of cyclotide expression, distribution, and phylogeny rapidly increase, the authors have proposed the inclusion of information pertaining to plant species that have been analyzed but do not appear to express cyclotides into the CyBase database. CyBase is dedicated to providing web tools and information about cyclic peptides and proteins to the scientific community. Including detailed information about sampling and analysis parameters of plant species that have been investigated but not published elsewhere should assist in the process of selecting species for establishing new cyclotide discovery projects, as well as for detailed reanalysis using alternative technical approaches. In summary, the collection and deposition of all plant species that have been examined (whether cyclotides have been found or not) would help to impart a deeper understanding of cyclotide discovery, evolution, and physiological function.

  18. Developing and Testing Simulated Occupational Experiences for Distributive Education Students in Rural Communities: Volume III: Training Plans: Final Report.

    ERIC Educational Resources Information Center

    Virginia Polytechnic Inst. and State Univ., Blacksburg.

    Volume 3 of a three volume final report presents prototype job training plans developed as part of a research project which pilot tested a distributive education program for rural schools utilizing a retail store simulation plan. The plans are for 15 entry-level and 15 career-level jobs in seven categories of distributive business (department…

  19. Intramolecular stable isotope distributions detect plant metabolic responses on century time scales

    NASA Astrophysics Data System (ADS)

    Schleucher, Jürgen; Ehlers, Ina; Augusti, Angela; Betson, Tatiana

    2014-05-01

    Plants respond to environmental changes on a vast range of time scales, and plant gas exchanges constitute important feedback mechanisms in the global C cycle. Responses on time scales of decades to centuries are most important for climate models, for prediction of crop productivity, and for adaptation to climate change. Unfortunately, responses on these timescale are least understood. We argue that the knowledge gap on intermediate time scales is due to a lack of adequate methods that can bridge between short-term manipulative experiments (e.g. FACE) and paleo research. Manipulative experiments in plant ecophysiology give information on metabolism on time scales up to years. However, this information cannot be linked to results from retrospective studies in paleo research, because little metabolic information can be derived from paleo archives. Stable isotopes are prominent tools in plant ecophysiology, biogeochemistry and in paleo research, but in all applications to date, isotope ratios of whole molecules are measured. However, it is well established that stable isotope abundance varies among intramolecular groups of biochemical metabolites, that is each so-called "isotopomer" has a distinct abundance. This intramolecular variation carries information on metabolic regulation, which can even be traced to individual enzymes (Schleucher et al., Plant, Cell Environ 1999). Here, we apply intramolecular isotope distributions to study the metabolic response of plants to increasing atmospheric [CO2] during the past century. Greenhouse experiments show that the deuterium abundance among the two positions in the C6H2 group of photosynthetic glucose depends on [CO2] during growth. This is observed for all plants using C3 photosynthesis, and reflects the metabolic flux ratio between photorespiration and photosynthesis. Photorespiration is a major C flux that limits assimilation in C3 plants, which encompass the overwhelming fraction of terrestrial photosynthesis and the

  20. Providing more informative projections of climate change impact on plant distribution in a mountain environment

    NASA Astrophysics Data System (ADS)

    Randin, C.; Engler, R.; Pearman, P.; Vittoz, P.; Guisan, A.

    2007-12-01

    Due to their conic shape and the reduction of area with increasing elevation, mountain ecosystems were early identified as potentially very sensitive to global warming. Moreover, mountain systems may experience unprecedented rates of warming during the next century, two or three times higher than that records of the 20th century. In this context, species distribution models (SDM) have become important tools for rapid assessment of the impact of accelerated land use and climate change on the distribution plant species. In this study, we developed and tested new predictor variables for species distribution models (SDM), specific to current and future geographic projections of plant species in a mountain system, using the Western Swiss Alps as model region. Since meso- and micro-topography are relevant to explain geographic patterns of plant species in mountain environments, we assessed the effect of scale on predictor variables and geographic projections of SDM. We also developed a methodological framework of space-for-time evaluation to test the robustness of SDM when projected in a future changing climate. Finally, we used a cellular automaton to run dynamic simulations of plant migration under climate change in a mountain landscape, including realistic distance of seed dispersal. Results of future projections for the 21st century were also discussed in perspective of vegetation changes monitored during the 20th century. Overall, we showed in this study that, based on the most severe A1 climate change scenario and realistic dispersal simulations of plant dispersal, species extinctions in the Western Swiss Alps could affect nearly one third (28.5%) of the 284 species modeled by 2100. With the less severe B1 scenario, only 4.6% of species are predicted to become extinct. However, even with B1, 54% (153 species) may still loose more than 80% of their initial surface. Results of monitoring of past vegetation changes suggested that plant species can react quickly to the

  1. Remote sensing-based characterization, 2-m, Plant Functional Type Distributions, Barrow Environmental Observatory, 2010

    DOE Data Explorer

    Zachary Langford; Forrest Hoffman; Jitendra Kumar

    2014-01-01

    Arctic ecosystems have been observed to be warming faster than the global average and are predicted to experience accelerated changes in climate due to global warming. Arctic vegetation is particularly sensitive to warming conditions and likely to exhibit shifts in species composition, phenology and productivity under changing climate. Mapping and monitoring of changes in vegetation is essential to understand the effect of climate change on the ecosystem functions. Vegetation exhibits unique spectral characteristics which can be harnessed to discriminate plant types and develop quantitative vegetation indices. We have combined high resolution multi-spectral remote sensing from the WorldView 2 satellite with LIDAR-derived digital elevation models to characterize the tundra landscape on the North Slope of Alaska. Classification of landscape using spectral and topographic characteristics yields spatial regions with expectedly similar vegetation characteristics. A field campaign was conducted during peak growing season to collect vegetation harvests from a number of 1m x 1m plots in the study region, which were then analyzed for distribution of vegetation types in the plots. Statistical relationships were developed between spectral and topographic characteristics and vegetation type distributions at the vegetation plots. These derived relationships were employed to statistically upscale the vegetation distributions for the landscape based on spectral characteristics. Vegetation distributions developed are being used to provide Plant Functional Type (PFT) maps for use in the Community Land Model (CLM).

  2. Vertical distribution of radiocesium in coniferous forest soil after the Fukushima nuclear power plant accident.

    PubMed

    Teramage, Mengistu T; Onda, Yuichi; Patin, Jeremy; Kato, Hiroaki; Gomi, Takashi; Nam, Sooyoun

    2014-11-01

    This study deals with the description of the vertical distribution of radiocaesium ((137)Cs and (134)Cs) in a representative coniferous forest soil, investigated 10 months after the Fukushima radioactive fallout. During soil sampling, the forest floor components (understory plants, litter (Ol-) and fermented layers (Of)) were collected and treated separately. The results indicate that radiocesium is concentrated in the forest floor, and high radiocesium transfer factor observed in the undergrowth plants (3.3). This made the forest floor an active exchanging interphase for radiocesium. The raw organic layer (Ol + Of) holds 52% (5.3 kBq m(-2)) of the Fukushima-derived and 25% (0.7 kBq m(-2)) of the pre-Fukushima (137)Cs at the time of the soil sampling. Including the pre-Fukushima (137)Cs, 99% of the total soil inventory was in the upper 10 cm, in which the organic matter (OM) content was greater than 10%, suggesting the subsequent distribution most likely depends on the OM turnover. However, the small fraction of the Fukushima-derived (137)Cs at a depth of 16 cm is most likely due to the infiltration of radiocesium-circumscribed rainwater during the fallout before that selective adsorption prevails and reduces the migration of soluble (137)Cs. The values of the depth distribution parameters revealed that the distribution of the Fukushima-derived (137)Cs was somewhat rapid.

  3. Sex ratio and spatial distribution of male and female Antennaria dioica (Asteraceae) plants

    NASA Astrophysics Data System (ADS)

    Varga, Sandra; Kytöviita, Minna-Maarit

    2011-09-01

    Sex ratio, sex spatial distribution and sexual dimorphism in reproduction and arbuscular mycorrhizal colonisation were investigated in the dioecious clonal plant Antennaria dioica (Asteraceae). Plants were monitored for five consecutive years in six study plots in Oulanka, northern Finland. Sex ratio, spatial distribution of sexes, flowering frequency, number of floral shoots and the number and weight of inflorescences were recorded. In addition, intensity of mycorrhizal fungi in the roots was assessed. Both sexes flowered each year with a similar frequency, but the overall genet sex ratio was strongly female-biased. The bivariate Ripley's analysis of the sex distribution showed that within most plots sexes were randomly distributed except for one plot. Sexual dimorphism was expressed as larger floral and inflorescence production and heavier inflorescences in males. In addition, the roots of both sexes were colonised to a similar extent by arbuscular mycorrhizal fungi. The female sex-biased flowering ratios reported are not consistent among years and cannot be explained in terms of spatial segregation of the sexes or sex lability. The possible reasons for the female-biased sex ratio are discussed.

  4. Economic optimization of the energy transport component of a large distributed solar power plant

    NASA Technical Reports Server (NTRS)

    Turner, R. H.

    1976-01-01

    A solar thermal power plant with a field of collectors, each locally heating some transport fluid, requires a pipe network system for eventual delivery of energy power generation equipment. For a given collector distribution and pipe network geometry, a technique is herein developed which manipulates basic cost information and physical data in order to design an energy transport system consistent with minimized cost constrained by a calculated technical performance. For a given transport fluid and collector conditions, the method determines the network pipe diameter and pipe thickness distribution and also insulation thickness distribution associated with minimum system cost; these relative distributions are unique. Transport losses, including pump work and heat leak, are calculated operating expenses and impact the total system cost. The minimum cost system is readily selected. The technique is demonstrated on six candidate transport fluids to emphasize which parameters dominate the system cost and to provide basic decision data. Three different power plant output sizes are evaluated in each case to determine severity of diseconomy of scale.

  5. Abundance, Distribution, and Activity of Fe(II)-Oxidizing and Fe(III)-Reducing Microorganisms in Hypersaline Sediments of Lake Kasin, Southern Russia

    PubMed Central

    Emmerich, Maren; Bhansali, Ankita; Lösekann-Behrens, Tina; Schröder, Christian; Kappler, Andreas

    2012-01-01

    The extreme osmotic conditions prevailing in hypersaline environments result in decreasing metabolic diversity with increasing salinity. Various microbial metabolisms have been shown to occur even at high salinity, including photosynthesis as well as sulfate and nitrate reduction. However, information about anaerobic microbial iron metabolism in hypersaline environments is scarce. We studied the phylogenetic diversity, distribution, and metabolic activity of iron(II)-oxidizing and iron(III)-reducing Bacteria and Archaea in pH-neutral, iron-rich salt lake sediments (Lake Kasin, southern Russia; salinity, 348.6 g liter−1) using a combination of culture-dependent and -independent techniques. 16S rRNA gene clone libraries for Bacteria and Archaea revealed a microbial community composition typical for hypersaline sediments. Most-probable-number counts confirmed the presence of 4.26 × 102 to 8.32 × 103 iron(II)-oxidizing Bacteria and 4.16 × 102 to 2.13 × 103 iron(III)-reducing microorganisms per gram dry sediment. Microbial iron(III) reduction was detected in the presence of 5 M NaCl, extending the natural habitat boundaries for this important microbial process. Quantitative real-time PCR showed that 16S rRNA gene copy numbers of total Bacteria, total Archaea, and species dominating the iron(III)-reducing enrichment cultures (relatives of Halobaculum gomorrense, Desulfosporosinus lacus, and members of the Bacilli) were highest in an iron oxide-rich sediment layer. Combined with the presented geochemical and mineralogical data, our findings suggest the presence of an active microbial iron cycle at salt concentrations close to the solubility limit of NaCl. PMID:22504804

  6. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    PubMed

    Choe, Hyeyeong; Thorne, James H; Seo, Changwan

    2016-01-01

    Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS) multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD) calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the threshold and scale

  7. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model

    PubMed Central

    Choe, Hyeyeong; Thorne, James H.; Seo, Changwan

    2016-01-01

    Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS) multi-response species distribution model to overcome species’ data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species’ ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species’ presence points, and the mean, median, and one standard deviation (SD) calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the threshold and scale

  8. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    PubMed

    Choe, Hyeyeong; Thorne, James H; Seo, Changwan

    2016-01-01

    Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS) multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD) calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the threshold and scale

  9. Novel NAD+-Farnesal Dehydrogenase from Polygonum minus Leaves. Purification and Characterization of Enzyme in Juvenile Hormone III Biosynthetic Pathway in Plant

    PubMed Central

    Mohamed-Hussein, Zeti-Azura; Ng, Chyan Leong

    2016-01-01

    Juvenile Hormone III is of great concern due to negative effects on major developmental and reproductive maturation in insect pests. Thus, the elucidation of enzymes involved JH III biosynthetic pathway has become increasing important in recent years. One of the enzymes in the JH III biosynthetic pathway that remains to be isolated and characterized is farnesal dehydrogenase, an enzyme responsible to catalyze the oxidation of farnesal into farnesoic acid. A novel NAD+-farnesal dehydrogenase of Polygonum minus was purified (315-fold) to apparent homogeneity in five chromatographic steps. The purification procedures included Gigacap S-Toyopearl 650M, Gigacap Q-Toyopearl 650M, and AF-Blue Toyopearl 650ML, followed by TSK Gel G3000SW chromatographies. The enzyme, with isoelectric point of 6.6 is a monomeric enzyme with a molecular mass of 70 kDa. The enzyme was relatively active at 40°C, but was rapidly inactivated above 45°C. The optimal temperature and pH of the enzyme were found to be 35°C and 9.5, respectively. The enzyme activity was inhibited by sulfhydryl agent, chelating agent, and metal ion. The enzyme was highly specific for farnesal and NAD+. Other terpene aldehydes such as trans- cinnamaldehyde, citral and α- methyl cinnamaldehyde were also oxidized but in lower activity. The Km values for farnesal, citral, trans- cinnamaldehyde, α- methyl cinnamaldehyde and NAD+ were 0.13, 0.69, 0.86, 1.28 and 0.31 mM, respectively. The putative P. minus farnesal dehydrogenase that’s highly specific towards farnesal but not to aliphatic aldehydes substrates suggested that the enzyme is significantly different from other aldehyde dehydrogenases that have been reported. The MALDI-TOF/TOF-MS/MS spectrometry further identified two peptides that share similarity to those of previously reported aldehyde dehydrogenases. In conclusion, the P. minus farnesal dehydrogenase may represent a novel plant farnesal dehydrogenase that exhibits distinctive substrate specificity

  10. Novel NAD+-Farnesal Dehydrogenase from Polygonum minus Leaves. Purification and Characterization of Enzyme in Juvenile Hormone III Biosynthetic Pathway in Plant.

    PubMed

    Seman-Kamarulzaman, Ahmad-Faris; Mohamed-Hussein, Zeti-Azura; Ng, Chyan Leong; Hassan, Maizom

    2016-01-01

    Juvenile Hormone III is of great concern due to negative effects on major developmental and reproductive maturation in insect pests. Thus, the elucidation of enzymes involved JH III biosynthetic pathway has become increasing important in recent years. One of the enzymes in the JH III biosynthetic pathway that remains to be isolated and characterized is farnesal dehydrogenase, an enzyme responsible to catalyze the oxidation of farnesal into farnesoic acid. A novel NAD+-farnesal dehydrogenase of Polygonum minus was purified (315-fold) to apparent homogeneity in five chromatographic steps. The purification procedures included Gigacap S-Toyopearl 650M, Gigacap Q-Toyopearl 650M, and AF-Blue Toyopearl 650ML, followed by TSK Gel G3000SW chromatographies. The enzyme, with isoelectric point of 6.6 is a monomeric enzyme with a molecular mass of 70 kDa. The enzyme was relatively active at 40°C, but was rapidly inactivated above 45°C. The optimal temperature and pH of the enzyme were found to be 35°C and 9.5, respectively. The enzyme activity was inhibited by sulfhydryl agent, chelating agent, and metal ion. The enzyme was highly specific for farnesal and NAD+. Other terpene aldehydes such as trans- cinnamaldehyde, citral and α- methyl cinnamaldehyde were also oxidized but in lower activity. The Km values for farnesal, citral, trans- cinnamaldehyde, α- methyl cinnamaldehyde and NAD+ were 0.13, 0.69, 0.86, 1.28 and 0.31 mM, respectively. The putative P. minus farnesal dehydrogenase that's highly specific towards farnesal but not to aliphatic aldehydes substrates suggested that the enzyme is significantly different from other aldehyde dehydrogenases that have been reported. The MALDI-TOF/TOF-MS/MS spectrometry further identified two peptides that share similarity to those of previously reported aldehyde dehydrogenases. In conclusion, the P. minus farnesal dehydrogenase may represent a novel plant farnesal dehydrogenase that exhibits distinctive substrate specificity towards

  11. Within-plant distribution of cotton aphids, Aphis gossypii Glover (Hemiptera: Aphididae), in Bt and non-Bt cotton fields.

    PubMed

    Fernandes, F S; Ramalho, F S; Nascimento, J L; Malaquias, J B; Nascimento, A R B; Silva, C A D; Zanuncio, J C

    2012-02-01

    Knowledge of the vertical and horizontal distribution of Aphis gossypii Glover (Hemiptera: Aphididae) on genetically modified cotton plants over time could help optimize decision-making in integrated cotton aphid management programs. Therefore, the aim of the present study was to determine the vertical and horizontal distribution of A. gossypii in non-transgenic Bt cotton and transgenic Bt-cotton over time during two cotton seasons by examining plants throughout the seasons. There was no significant interaction between years and cotton cultivar treatments for apterous or alate aphids. Considering year-to-year data, analyses on season-long averages of apterous or alate aphids showed that aphid densities per plant did not differ among years. The number of apterous aphids found per plant for the Bt transgenic cultivar (2427 apterous aphids per plant) was lower than for its isoline (3335 apterous aphids per plant). The number of alate aphids found per plant on the Bt transgenic cultivar (12.28 alate aphids per plant) was lower than for the isoline (140.56 alate aphids per plant). With regard to the vertical distribution of apterous aphids or alate aphids, there were interactions between cotton cultivar, plant age and plant region. We conclude that in comparison to non-Bt cotton (DP 4049), Bt cotton (DP 404 BG (Bollgard)) has significant effects on the vertical, horizontal, spatial and temporal distribution patterns of A. gossypii, showing changes in its distribution behaviour inside the plant as the cotton crop develops. The results of our study are relevant for understanding the vertical and horizontal distribution of A. gossypii on Bt cotton cultivar (DP 404 BG (Bollgard)) and on its isoline (DP 4049), and could be useful in decision-making, implementing controls and determining the timing of population peaks of this insect.

  12. Invasive giant hogweeds in Poland: Risk of burns among forestry workers and plant distribution.

    PubMed

    Rzymski, Piotr; Klimaszyk, Piotr; Poniedziałek, Barbara

    2015-12-01

    The Caucasian giant hogweeds (Heracleum sosnowskyi Manden. and Heracleum mantegazzianum Sommier et Lever) are aggressive invaders that are successfully spreading in different parts of the world. Exposure of human skin to these plants may lead to phototoxicity and even chemical burns manifested by cutaneous, full-thickness, and long-lasting dermatitis, and in extreme cases, massive skin necrosis. Forestry workers are a group with potentially increased risk of exposure to these plants because of the outdoor nature of their work and their active involvement in managing invasive species. Therefore, in this study, we aimed at investigating their level of awareness with regard to the giant hogweeds in Poland. The morphology of the plants, health threats, treatment, and control methods were all considered. We also evaluated the distribution of these plants within forest districts in Poland. For this reason, we surveyed 1563 employees (forest rangers, manual workers, and administration staff) of the State Forests National Forest Holding in Poland "State Forests," working in 367 different forest districts. It was initially found that the forestry workers were generally aware of the giant hogweeds' morphology and phototoxicity. More than 20% of the surveyed individuals had been exposed to these plants at least once in their lives, but only less than half of them were aware of proceeding afterward. At the same time, <35% of those surveyed had any knowledge of the control and management of these giant hogweeds. As demonstrated by our study, stands of these species are widely distributed within the Polish forest districts (reported in over 50%). Therefore, there is an urgent need to implement an efficient, multistrategic, and long-term approach to both control their spread and protect human health.

  13. Native Australian plant extracts differentially induce Collagen I and Collagen III in vitro and could be important targets for the development of new wound healing therapies.

    PubMed

    Adams, Damian H; Shou, Qingyao; Wohlmuth, Hans; Cowin, Allison J

    2016-03-01

    Australian native plants have a long history of therapeutic use in indigenous cultures, however, they have been poorly studied scientifically. We analysed the effects of 14 plant derived compounds from the species Pilidiostigma glabrum, Myoporum montanum, Geijera parviflora, and Rhodomyrtus psidioides for their potential wound healing properties by assessing their ability to induce or suppress Collagen I and Collagen III expression in human skin fibroblasts in culture. The compound 7-geranyloxycoumarin was able to significantly increase Collagen I (23.7%, p<0.0002) expression in comparison to control. Significant suppression of Collagen III was observed for the compounds flindersine (11.1%, p<0.02), and (N-acetoxymethyl) flindersine (27%, p<0.00005). The implications of these finding is that these compounds could potentially alter the expression of different collagens in the skin allowing for the potential development of new wound healing therapies and new approaches for treating various skin diseases as well as photo (sun) damaged, and aged skin.

  14. The spatial distribution of threats to plant species with extremely small populations

    NASA Astrophysics Data System (ADS)

    Wang, Chunjing; Zhang, Jing; Wan, Jizhong; Qu, Hong; Mu, Xianyun; Zhang, Zhixiang

    2016-04-01

    Many biological conservationists take actions to conserve plant species with extremely small populations (PSESP) in China; however, there have been few studies on the spatial distribution of threats to PSESP. Hence, we selected distribution data of PSESP and made a map of the spatial distribution of threats to PSESP in China. First, we used the weight assignment method to evaluate the threat risk to PSESP at both country and county scales. Second, we used a geographic information system to map the spatial distribution of threats to PSESP, and explored the threat factors based on linear regression analysis. Finally, we suggested some effective conservation options. We found that the PSESP with high values of protection, such as the plants with high scientific research values and ornamental plants, were threatened by over-exploitation and utilization, habitat fragmentation, and a small sized wild population in broad-leaved forests and bush fallows. We also identified some risk hotspots for PSESP in China. Regions with low elevation should be given priority for ex- and in-situ conservation. Moreover, climate change should be considered for conservation of PSESP. To avoid intensive over-exploitation or utilization and habitat fragmentation, in-situ conservation should be practiced in regions with high temperatures and low temperature seasonality, particularly in the high risk hotspots for PSESP that we proposed. Ex-situ conservation should be applied in these same regions, and over-exploitation and utilization of natural resources should be prevented. It is our goal to apply the concept of PSESP to the global scale in the future.

  15. Cellular distribution of transforming growth factor-beta 1 and procollagen types I, III, and IV transcripts in carbon tetrachloride-induced rat liver fibrosis.

    PubMed Central

    Nakatsukasa, H; Nagy, P; Evarts, R P; Hsia, C C; Marsden, E; Thorgeirsson, S S

    1990-01-01

    The cellular distribution and temporal expression of transcripts from transforming growth factor-beta 1 (TGF-beta 1) and procollagen alpha 1(I), alpha 1(III), and alpha 1(IV) genes were studied in carbon tetrachloride (CCl4)-induced rat liver fibrosis by using in situ hybridization technique. During the fibrotic process, TGF-beta 1 and procollagen genes were similarly and predominantly expressed in Desmin-positive perisinusoidal cells (e.g., fat-storing cells and myofibroblasts) and fibroblasts and their expression continued to be higher than those observed in control rats. These transcripts were also observed in inflammatory cells mainly granulocytes and macrophage-like cells at the early stages of liver fibrosis. The production of extracellular matrix along small blood vessels and fibrous septa coincided with the expression of these genes. Expression of TGF-beta 1 and procollagen genes were not detected in hepatocytes throughout the experiment. No significant differences in cellular distribution or time course of gene expression among procollagen alpha 1(I), alpha 1(III), and alpha 1(IV) were observed. Desmin-positive perisinusoidal cells and fibroblasts appeared to play the principal role in synthesis of collagens in CCl4-induced hepatic fibrosis. The simultaneous expression of TGF-beta 1 and procollagen genes in mesenchymal cells, including Desmin-positive perisinusoidal cells, during hepatic fibrosis suggests the possibility that TGF-beta 1 may have an important role in the production of fibrosis. Images PMID:1693377

  16. Flight Investigation of the Cooling Characteristics of a Two-row Radial Engine Installation III : Engine Temperature Distribution

    NASA Technical Reports Server (NTRS)

    Rennak, Robert M; Messing, Wesley E; Morgan, James E

    1946-01-01

    The temperature distribution of a two-row radial engine in a twin-engine airplane has been investigated in a series of flight tests. The test engine was operated over a wide range of conditions at density altitudes of 5000 and 20,000 feet; quantitative results are presented showing the effects of flight and engine variables upon average engine temperature and over-all temperature spread. Discussions of the effect of the variables on the shape of the temperature patterns and on the temperature distribution of individual cylinders are also included. The results indicate that, for the tests conducted, the temperature distribution patterns were chiefly determined by the fuel-air ratio and cooling-air distributions. It was possible to calculate individual cylinder temperature, on the assumption of equal power distribution among cylinders, to within an average of plus or minus 14 degrees F. of the actual temperature. A considerable change occurred in either the spread or the thrust axis, the average engine fuel-air ratio, the engine speed, the power, or the blower ratio. Smaller effects on the temperature pattern were noticed with a change in cowl-flap opening and altitude. In most of the tests, a change in conditions affected the temperature of the barrels less than that of the heads. The variation of flight and engine variables had a negligible effect on the temperature distributions of the individual cylinders. (author)

  17. Uptake and reduction of Cr(VI) to Cr(III) by mesquite (Prosopis spp.): chromate-plant interaction in hydroponics and solid media studied using XAS.

    PubMed

    Aldrich, M V; Gardea-Torresdey, J L; Peralta-Videa, J R; Parsons, J G

    2003-05-01

    Chromium (Cr) is a well-established carcinogen that is a contaminant at half of the EPA Superfund sites in the United States. Two separate studies were performed to investigate the possibility that mesquite (Prosopis spp.), which is an indigenous desert plant species, can remove Cr from the environment via active transport systems to the aerial portions of the plant. The first study was performed by growing mesquite on solid media (agar) at Cr(VI) concentrations of 75 and 125 ppm. The accumulation found in the leaves under the present conditions indicated that mesquite could be classified as a hyperaccumulator of chromium. The second study was conducted to investigate the differences between the type of Cr ligand involved in Cr uptake with agar and hydroponic cultures. We used X-ray absorption spectroscopy (XAS) to determine the mechanisms involved in the uptake and binding of Cr(VI) in live mesquite tissue. The XAS results for this study showed that some of the supplied Cr(VI) was uptaken by the mesquite roots; however, the data analyses of the plant tissues demonstrated that it was fully reduced to Cr(III) in the leaf tissues. Experiments are currently being performed to evaluate the behavior of the Mesquite plant using lower Cr concentrations.

  18. The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions

    USGS Publications Warehouse

    DeJager, Nathan R.; Rohweder, Jason J.; Yin, Yao; Hoy, Erin E.

    2016-01-01

    Questions How is the distribution of different plant communities associated with patterns of flood inundation across a large floodplain landscape? Location Thirty-eight thousand nine hundred and seventy hectare of floodplain, spanning 320 km of the Upper Mississippi River (UMR). Methods High-resolution elevation data (Lidar) and 30 yr of daily river stage data were integrated to produce a ‘floodscape’ map of growing season flood inundation duration. The distributions of 16 different remotely sensed plant communities were quantified along the gradient of flood duration. Results Models fitted to the cumulative frequency of occurrence of different vegetation types as a function of flood duration showed that most types exist along a continuum of flood-related occurrence. The diversity of community types was greatest at high elevations (0–10 d of flooding), where both upland and lowland community types were found, as well as at very low elevations (70–180 d of flooding), where a variety of lowland herbaceous communities were found. Intermediate elevations (20–60 d of flooding) tended to be dominated by floodplain forest and had the lowest diversity of community types. Conclusions Although variation in flood inundation is often considered to be the main driver of spatial patterns in floodplain plant communities, few studies have quantified flood–vegetation relationships at broad scales. Our results can be used to identify targets for restoration of historical hydrological regimes or better anticipate hydro-ecological effects of climate change at broad scales.

  19. Distribution and seasonal occurrence of UV filters in rivers and wastewater treatment plants in Korea.

    PubMed

    Ekpeghere, Kalu Ibe; Kim, Un-Jung; O, Sung-Hee; Kim, Hee-Young; Oh, Jeong-Eun

    2016-01-15

    The occurrence and distribution of eight UV filters benzophenone (BP), benzophenone-3 (BP-3), ethylhexyl methoxy cinnamate (EHMC), 4-methylbenzylidene camphor (4-MBC), 2-ethylhexyl 4-dimethylaminobenzoate (OD-PABA), 2-ethylhexyl salicylate (EHS), isoamyl benzoate, and benzyl cinnamate in eleven sites among three rivers, five sewage treatment plants (STPs), and four wastewater treatment plants (WWTPs) located in different parts of Korea was investigated. The total concentrations of UV filters in the three sampled seasons were 62.9-412 ng L(-1) (river), 417-5055 ng L(-1) (STP influent), 108-2201 ng L(-1) (STP effluent), 122-4154 ng L(-1) (WWTP influent), and 120-849 ng L(-1) (WWTP effluent). The concentration of the target pollutants in the influent of the treatment systems was directly proportional to the resident population density. A seasonal increase of >27% was observed in the total concentration of the UV filters in the rivers and influents of the treatment plants (TPs) during summer. BP, BP-3, EHMC, 4-MBC, and EHS were the most dominant, showing a distinct distribution pattern that was dependent on the effectiveness of the treatment process and properties of each compound. The concentrations of the UV filters were higher in the TPs influents than in the rivers, and the most dominant UV filters in the rivers were those with low removal rate. Although biological treatment processes favored the removal of the UV filter compounds in the TPs, complete removal was not achieved before discharge into the rivers.

  20. Distribution and seasonal occurrence of UV filters in rivers and wastewater treatment plants in Korea.

    PubMed

    Ekpeghere, Kalu Ibe; Kim, Un-Jung; O, Sung-Hee; Kim, Hee-Young; Oh, Jeong-Eun

    2016-01-15

    The occurrence and distribution of eight UV filters benzophenone (BP), benzophenone-3 (BP-3), ethylhexyl methoxy cinnamate (EHMC), 4-methylbenzylidene camphor (4-MBC), 2-ethylhexyl 4-dimethylaminobenzoate (OD-PABA), 2-ethylhexyl salicylate (EHS), isoamyl benzoate, and benzyl cinnamate in eleven sites among three rivers, five sewage treatment plants (STPs), and four wastewater treatment plants (WWTPs) located in different parts of Korea was investigated. The total concentrations of UV filters in the three sampled seasons were 62.9-412 ng L(-1) (river), 417-5055 ng L(-1) (STP influent), 108-2201 ng L(-1) (STP effluent), 122-4154 ng L(-1) (WWTP influent), and 120-849 ng L(-1) (WWTP effluent). The concentration of the target pollutants in the influent of the treatment systems was directly proportional to the resident population density. A seasonal increase of >27% was observed in the total concentration of the UV filters in the rivers and influents of the treatment plants (TPs) during summer. BP, BP-3, EHMC, 4-MBC, and EHS were the most dominant, showing a distinct distribution pattern that was dependent on the effectiveness of the treatment process and properties of each compound. The concentrations of the UV filters were higher in the TPs influents than in the rivers, and the most dominant UV filters in the rivers were those with low removal rate. Although biological treatment processes favored the removal of the UV filter compounds in the TPs, complete removal was not achieved before discharge into the rivers. PMID:26519573

  1. Leaf gas films, underwater photosynthesis and plant species distributions in a flood gradient.

    PubMed

    Winkel, Anders; Visser, Eric J W; Colmer, Timothy D; Brodersen, Klaus P; Voesenek, Laurentius A C J; Sand-Jensen, Kaj; Pedersen, Ole

    2016-07-01

    Traits for survival during flooding of terrestrial plants include stimulation or inhibition of shoot elongation, aerenchyma formation and efficient gas exchange. Leaf gas films form on superhydrophobic cuticles during submergence and enhance underwater gas exchange. The main hypothesis tested was that the presence of leaf gas films influences the distribution of plant species along a natural flood gradient. We conducted laboratory experiments and field observations on species distributed along a natural flood gradient. We measured presence or absence of leaf gas films and specific leaf area of 95 species. We also measured, gas film retention time during submergence and underwater net photosynthesis and dark respiration of 25 target species. The presence of a leaf gas film was inversely correlated to flood frequency and duration and reached a maximum value of 80% of the species in the rarely flooded locations. This relationship was primarily driven by grasses that all, independently of their field location along the flood gradient, possess gas films when submerged. Although the present study and earlier experiments have shown that leaf gas films enhance gas exchange of submerged plants, the ability of species to form leaf gas films did not show the hypothesized relationship with species composition along the flood gradient.

  2. Leaf gas films, underwater photosynthesis and plant species distributions in a flood gradient.

    PubMed

    Winkel, Anders; Visser, Eric J W; Colmer, Timothy D; Brodersen, Klaus P; Voesenek, Laurentius A C J; Sand-Jensen, Kaj; Pedersen, Ole

    2016-07-01

    Traits for survival during flooding of terrestrial plants include stimulation or inhibition of shoot elongation, aerenchyma formation and efficient gas exchange. Leaf gas films form on superhydrophobic cuticles during submergence and enhance underwater gas exchange. The main hypothesis tested was that the presence of leaf gas films influences the distribution of plant species along a natural flood gradient. We conducted laboratory experiments and field observations on species distributed along a natural flood gradient. We measured presence or absence of leaf gas films and specific leaf area of 95 species. We also measured, gas film retention time during submergence and underwater net photosynthesis and dark respiration of 25 target species. The presence of a leaf gas film was inversely correlated to flood frequency and duration and reached a maximum value of 80% of the species in the rarely flooded locations. This relationship was primarily driven by grasses that all, independently of their field location along the flood gradient, possess gas films when submerged. Although the present study and earlier experiments have shown that leaf gas films enhance gas exchange of submerged plants, the ability of species to form leaf gas films did not show the hypothesized relationship with species composition along the flood gradient. PMID:26846194

  3. Measurement of the Flux and Zenith-Angle Distribution of Upward Through-Going Muons in Kamiokande II+III

    NASA Astrophysics Data System (ADS)

    Hatakeyama, S.; Hara, T.; Fukuda, Y.; Hayakawa, T.; Inoue, K.; Ishihara, K.; Ishino, H.; Joukou, S.; Kajita, T.; Kasuga, S.; Koshio, Y.; Kumita, T.; Matsumoto, K.; Nakahata, M.; Nakamura, K.; Okumura, K.; Sakai, A.; Shiozawa, M.; Suzuki, J.; Suzuki, Y.; Tomoeda, T.; Totsuka, Y.; Hirata, K. S.; Kihara, K.; Oyama, Y.; Koshiba, M.; Nishijima, K.; Horiuchi, T.; Fujita, K.; Koga, M.; Maruyama, T.; Suzuki, A.; Mori, M.; Suda, T.; Suzuki, A. T.; Ishizuka, T.; Miyano, K.; Okazawa, H.; Nagashima, Y.; Takita, M.; Yamaguchi, T.; Hayato, Y.; Kaneyuki, K.; Suzuki, T.; Takeuchi, Y.; Tanimori, T.; Tasaka, S.; Ichihara, E.; Miyamoto, S.; Nishikawa, K.

    1998-09-01

    The flux of upward through-going muons of minimum (mean) threshold energy >1.6 (3.0) GeV is measured, based on a total of 372 events observed by the Kamiokande II+III detector during 2456 detector live days. The observed muon flux was Φobs = [1.94+/-0.10\\(stat.\\)+0.07-0.06sys.\\)]×10-13 cm-2 s-1 sr-1, which is compared to an expected value of Φtheo = [2.46+/-0.54\\(theo.\\)]×10-13 cm-2 s-1 sr-1. The observation is in agreement with the prediction within the errors. The zenith-angle dependence of the observed upward through-going muons supports the previous indication of neutrino oscillations made by Kamiokande using sub- and multi-GeV atmospheric neutrino events.

  4. Distribution and antimicrobial potential of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L.

    PubMed

    Mishra, Vineet Kumar; Singh, Garima; Passari, Ajit Kumar; Yadav, Mukesh Kumar; Gupta, Vijai Kumar; Singh, Bhim Pratap

    2016-03-01

    Distributions of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L. was studied and 91 isolates belonging to 18 genera were recovered. The isolates were distributed to sordariomycetes (62.63%), dothideomycetes (19.78%), eurotiomycetes (7.69%), zygomycetes (4.19%), agaricomycetes (1.09%), and mycelia sterilia (4.39%). Based on colony morphology and examination of spores, the isolates were classified into 18 taxa, of which Colletotrichum, Phomopsis and Phoma were dominant, their relative frequencies were 23.07%, 17.58% and 12.08% respectively. The colonization rate of endophytic fungi was determined and found to be significantly higher in leaf segments (50.76%), followed by root (41.53%) and stem tissues (27.69%). All the isolates were screened for antimicrobial activity and revealed that 26.37% endophytic fungi were active against one or more pathogens. Twenty four isolates showing significant antimicrobial activity were identified by sequencing the ITS1-5.8S-ITS2 region of rRNA gene. Results indicated that endophytic fungi associated with leaf were functionally versatile as they showed antimicrobial activity against most of the tested pathogens. The endophytic fungi Diaporthe phaseolorum var. meridionalis (KF193982) inhibited all the tested bacterial pathogens, whereas, Penicillium chermesinum (KM405640) displayed most significant antifungal activity. This seems to be the first hand report to understand the distribution and antimicrobial ability of endophytic fungi from ethno-medicinal plant M. malabathricum.

  5. [Soil Heavy Metal Spatial Distribution and Source Analysis Around an Aluminum Plant in Baotou].

    PubMed

    Zhang, Lian-ke; Li, Hai-peng; Huang, Xue-min; Li, Yu-mei; Jiao, Kun-ling; Sun, Peng; Wang, Wei-da

    2016-03-15

    The soil with 500 m distance from an aluminum plant in Baotou was studied. A total of 64 soil samples were taken from the 0-5 cm, 5-20 cm, 20-40 cm and 40-60 cm layers, and the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn were tested, respectively. The correlation analysis and principal component analysis were used to identify the sources of these heavy metals in soils. The results suggested that the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn in study area were 32.9, 50.35, 69.92, 43.78, 0.54, 554.42 and 36.65 mg · kg⁻¹ respectively. All seven heavy metals tested were overweight compared with the background values of soil in Inner Mongolia. The spatial distribution of heavy metals showed that the horizontal distribution of heavy metals was obviously enriched in the southwest, while in vertical distribution, the heavy metal content (0 to 5 cm) was highest in the surface soil, and the heavy metal content decreased with increasing depth and tended to be stabilized when the depth was over 20 cm. Source analysis showed that the source of Cu, Zn, Cr and Mn might be influenced by the aluminum plant and the surrounding industrial activity. The source of Pb and Cd might be mainly related to road transportation. The source of Ni may be affected by agricultural activities and soil parent material together. PMID:27337911

  6. [Soil Heavy Metal Spatial Distribution and Source Analysis Around an Aluminum Plant in Baotou].

    PubMed

    Zhang, Lian-ke; Li, Hai-peng; Huang, Xue-min; Li, Yu-mei; Jiao, Kun-ling; Sun, Peng; Wang, Wei-da

    2016-03-15

    The soil with 500 m distance from an aluminum plant in Baotou was studied. A total of 64 soil samples were taken from the 0-5 cm, 5-20 cm, 20-40 cm and 40-60 cm layers, and the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn were tested, respectively. The correlation analysis and principal component analysis were used to identify the sources of these heavy metals in soils. The results suggested that the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn in study area were 32.9, 50.35, 69.92, 43.78, 0.54, 554.42 and 36.65 mg · kg⁻¹ respectively. All seven heavy metals tested were overweight compared with the background values of soil in Inner Mongolia. The spatial distribution of heavy metals showed that the horizontal distribution of heavy metals was obviously enriched in the southwest, while in vertical distribution, the heavy metal content (0 to 5 cm) was highest in the surface soil, and the heavy metal content decreased with increasing depth and tended to be stabilized when the depth was over 20 cm. Source analysis showed that the source of Cu, Zn, Cr and Mn might be influenced by the aluminum plant and the surrounding industrial activity. The source of Pb and Cd might be mainly related to road transportation. The source of Ni may be affected by agricultural activities and soil parent material together.

  7. Distribution and antimicrobial potential of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L.

    PubMed

    Mishra, Vineet Kumar; Singh, Garima; Passari, Ajit Kumar; Yadav, Mukesh Kumar; Gupta, Vijai Kumar; Singh, Bhim Pratap

    2016-03-01

    Distributions of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L. was studied and 91 isolates belonging to 18 genera were recovered. The isolates were distributed to sordariomycetes (62.63%), dothideomycetes (19.78%), eurotiomycetes (7.69%), zygomycetes (4.19%), agaricomycetes (1.09%), and mycelia sterilia (4.39%). Based on colony morphology and examination of spores, the isolates were classified into 18 taxa, of which Colletotrichum, Phomopsis and Phoma were dominant, their relative frequencies were 23.07%, 17.58% and 12.08% respectively. The colonization rate of endophytic fungi was determined and found to be significantly higher in leaf segments (50.76%), followed by root (41.53%) and stem tissues (27.69%). All the isolates were screened for antimicrobial activity and revealed that 26.37% endophytic fungi were active against one or more pathogens. Twenty four isolates showing significant antimicrobial activity were identified by sequencing the ITS1-5.8S-ITS2 region of rRNA gene. Results indicated that endophytic fungi associated with leaf were functionally versatile as they showed antimicrobial activity against most of the tested pathogens. The endophytic fungi Diaporthe phaseolorum var. meridionalis (KF193982) inhibited all the tested bacterial pathogens, whereas, Penicillium chermesinum (KM405640) displayed most significant antifungal activity. This seems to be the first hand report to understand the distribution and antimicrobial ability of endophytic fungi from ethno-medicinal plant M. malabathricum. PMID:27097442

  8. Computer simulation of PPF distribution under blue and red LED light source for plant growth.

    PubMed

    Takita, S; Okamoto, K; Yanagi, T

    1996-12-01

    The superimposed pattern of "luminescence spectrum of blue light emitting diode (LED)" and "that of red LED", corresponds well to light absorption spectrum of chlorophyll. If these two kinds of LED are used as a light source, various plant cultivation experiments are possible. The cultivation experiments which use such light sources are becoming increasingly active, and in such experiments, it is very important to know the distribution of the photosynthetic photon flux (PPF) which exerts an important influence on photosynthesis. Therefore, we have developed a computer simulation system which can visualize the PPF distribution under a light source equipped with blue and red LEDs. In this system, an LED is assumed to be a point light source, and only the photons which are emitted directly from LED are considered. This simulation system can display a perspective view of the PPF distribution, a transverse and a longitudinal section of the distribution, and a contour map of the distribution. Moreover, a contour map of the ratio of the value of the PPF emitted by blue LEDs to that by blue and red LEDs can be displayed. As the representation is achieved by colored lines according to the magnitudes of the PPF in our system, a user can understand and evaluate the state of the PPF well.

  9. Within-plant distribution and binomial sampling of Pentalonia nigronervosa (Hemiptera: Aphididae) on banana.

    PubMed

    Robson, Jacqueline D; Wright, Mark G; Almeida, Rodrigo P P

    2006-12-01

    The banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae), infests banana (Musa spp.) worldwide. Pentalonia nigronervosa is the vector of Banana bunchy top virus (family Nanoviridae, genus Babuvirus) the etiological agent of Banana bunchy top disease (BBTD). BBTD is currently the most serious problem affecting banana in Hawaii. Despite the importance of this vector species, little is known about its biology or ecology. There are also no sampling plans available for P. nigronervosa. We conducted field surveys to develop a sampling plan for this pest. Ten plots were surveyed on seven commercial banana farms on the island of Oahu, HI, for the presence of P. nigronervosa on banana plantlets. We found aphids more frequently near the base of plants, followed by the newest unfurled leaf at the top of the plant. Aphids were least likely to be located on leaves in between the top and bottom of the plant. Aphid infestation on surveyed plots ranged from 8 to 95%. We developed a sequential binomial sampling plan based on our surveys. We also discovered that the within-plant distribution of P. nigronervosa is an important factor to consider when sampling for this pest. Our sampling plan will assist in the development of sustainable management practices for banana production.

  10. Distribution of 152Eu and 154Eu in the 'alluvial soil-rhizosphere-plant roots' system.

    PubMed

    Kropatcheva, Marya; Chuguevsky, Alexei; Melgunov, Mikhail

    2012-04-01

    Accumulation of (152)Eu and (15)(4)Eu isotopes in bulk soil and rhizosphere soil in the near-field zone of influence of the Krasnoyarsk Mining and Chemical Combine was studied. An uneven distribution of specific activity of Eu isotopes was observed, with the gross specific activities of the isotopes in the bulk soil exceeding those of the rhizosphere. In the most contaminated locations the fine and the coarse granulometric fractions are enriched with the isotopes. A laboratory experiment indicated potential removal of soluble Eu isotopes by river flood waters may amount to 3% of the total Eu in both bulk and rhizosphere soils. The root system of plants growing in the contaminated territory accumulates (152)Eu and (154)Eu, although the isotopes were not discovered in aboveground parts of plants. Root-hairs were found to be the most contaminated.

  11. Insights Into the Dynamics of Planetary Interiors Obtained Through the Study of Global Distribution of Volcanoes III: Lessons From Io.

    NASA Astrophysics Data System (ADS)

    Canon-Tapia, E.; Hamilton, C.; Lopes, R. M. C.

    2015-12-01

    Clues concerning dynamic aspects of planetary interiors can be obtained through the characterization of volcano distribution at a global scale. On past years, results obtained from global distribution of volcanism on Earth and Venus have been presented, and compared with each other. In this work, the global distribution of volcanism on Io (the innermost of Jupiter's Galilean satellites and the most volcanically active body in the Solar System) is explored using the same tools. Volcanic centers on Io can be divided in two groups: The first including positive thermal anomalies, or hotspots, and the second formed by volcano-tectonic depressions called paterae. Approximately 20% of the documented patera coincide with hotspots, but not all of Io's current volcanic activity is directly associated to paterae. It is uncertain whether hotspots located outside paterae represent volcanic systems still lacking a caldera-like structure, or they represent an entirely different type of volcanism. To account for this source of uncertainty, the analysis reported here was completed on different databases (hotspots, paterae, patera floor units and a combination of hotspots and paterae referred to as volcanic systems). In addition, the distribution of Io's mountains also was studied. As a result, we show that the main clusters of volcanism on Io support the existence of mantle convection patterns that include a combined heating between the astenosphere and the deep mantle (with the former source being more important, but not necessarily on a 2:1 proportion), takes place at moderate to high Reynolds numbers, and includes some degree of impermeability between the astenosphere and the mantle. We also show that although the long-wavelength volcano distribution is controlled by the patterns of mantle convection, the astenosphere serves as a buffer zone where magma is distributed laterally giving place to volcanic activity away from the zones of influence of the hot mantle isotherms. The

  12. Risks of nuclear waste disposal in space. III - Long-term orbital evolution of small particle distribution

    NASA Technical Reports Server (NTRS)

    Friedlander, A. L.; Wells, W. C.

    1980-01-01

    A study of long term risks is presented that treats an additional pathway that could result in earth reentry, namely, small radioactive particles released in solar orbit due to payload fragmentation by accidental explosion or meteoroid impact. A characterization of such an event and of the initial mass size distribution of particles is given for two extremes of waste form strength. Attention is given to numerical results showing the mass-time distribution of material and the fraction of initial mass intercepted by earth. It is concluded that it appears that program planners need not be to concerned about the risks of this particular failure mechanism and return pathway.

  13. Studies in Hawaiian Diptera III: New Distributional Records for Canacidae and a New Endemic Species of Procanace

    PubMed Central

    2016-01-01

    Abstract The distributions of Hawaiian Canacidae, comprising nearly 800 individual collection events, are reviewed and a total of four new island records are reported. These include Canaceoides angulatus from Kahoolawae and Procanace bifurcata from Molokai and Maui, and Procanace constricta from Oahu. A new species from Kauai, Procanace hardyi O'Grady and Pak, is described. This species is closely related to P. constricta from Oahu, Maui, Molokai and Hawaii and shares a similar constriction of the abdomen between tergites four and five but differs in the configuration of the seventh abdominal tergite. Detailed distribution maps for all species are included. PMID:27226743

  14. X-ray absorption spectroscopy of an investigational anticancer gallium(III) drug: interaction with serum proteins, elemental distribution pattern, and coordination of the compound in tissue.

    PubMed

    Hummer, Alfred A; Bartel, Caroline; Arion, Vladimir B; Jakupec, Michael A; Meyer-Klaucke, Wolfram; Geraki, Tina; Quinn, Paul D; Mijovilovich, Ana; Keppler, Bernhard K; Rompel, Annette

    2012-06-14

    Tris(8-quinolinolato)gallium(III) (1, KP46) is a very promising investigational anticancer drug. Its interaction with serum proteins, elemental distribution, and coordination in tissue were investigated with X-ray absorption (XAS) methods. Model compounds with mixed O, N, and/or S donor atoms are reported. The coordination and structure of 1 in cell culture medium (minimum essential medium, MEM) and fetal calf serum (FCS) were probed by XANES and EXAFS. The interaction of 1 with the serum proteins apotransferrin (apoTf) and human serum albumin (HSA) was addressed as well. By application of micro-XAS to tissue samples from mice treated with 1, the gallium distribution pattern was analyzed and compared to those of physiological trace elements. The complex 1 turned out to be very stable under physiological conditions, in cell culture media and in tissue samples. The coordination environment of the metal center remains intact in the presence of apoTf and HSA. The gallium distribution pattern in tumor and liver tissue revealed high similarities to the distribution patterns of Zn and Fe, minor similarities to Cu and Ni, and no similarity to Ca.

  15. Swan foraging shapes spatial distribution of two submerged plants, favouring the preferred prey species

    PubMed Central

    Sandsten, Håkan

    2008-01-01

    Compared to terrestrial environments, grazing intensity on belowground plant parts may be particularly strong in aquatic environments, which may have great effects on plant-community structure. We observed that the submerged macrophyte, Potamogeton pectinatus, which mainly reproduces with tubers, often grows at intermediate water depth and that P. perfoliatus, which mainly reproduces with rhizomes and turions, grows in either shallow or deep water. One mechanism behind this distributional pattern may be that swans prefer to feed on P. pectinatus tubers at intermediate water depths. We hypothesised that when swans feed on tubers in the sediment, P. perfoliatus rhizomes and turions may be damaged by the uprooting, whereas the small round tubers of P. pectinatus that escaped herbivory may be more tolerant to this bioturbation. In spring 2000, we transplanted P. perfoliatus rhizomes into a P. pectinatus stand and followed growth in plots protected and unprotected, respectively, from bird foraging. Although swan foraging reduced tuber biomass in unprotected plots, leading to lower P. pectinatus density in spring 2001, this species grew well both in protected and unprotected plots later that summer. In contrast, swan grazing had a dramatic negative effect on P. perfoliatus that persisted throughout the summer of 2001, with close to no plants in the unprotected plots and high densities in the protected plots. Our results demonstrate that herbivorous waterbirds may play a crucial role in the distribution and prevalence of specific plant species. Furthermore, since their grazing benefitted their preferred food source, the interaction between swans and P. pectinatus may be classified as ecologically mutualistic. PMID:18335250

  16. Burkholderia, a genus rich in plant-associated nitrogen fixers with wide environmental and geographic distribution.

    PubMed

    Estrada-De Los Santos, P; Bustillos-Cristales, R; Caballero-Mellado, J

    2001-06-01

    The genus Burkholderia comprises 19 species, including Burkholderia vietnamiensis which is the only known N(2)-fixing species of this bacterial genus. The first isolates of B. vietnamiensis were recovered from the rhizosphere of rice plants grown in a phytotron, but its existence in natural environments and its geographic distribution were not reported. In the present study, most N(2)-fixing isolates recovered from the environment of field-grown maize and coffee plants cultivated in widely separated regions of Mexico were phenotypically identified as B. cepacia using the API 20NE system. Nevertheless, a number of these isolates recovered from inside of maize roots, as well as from the rhizosphere and rhizoplane of maize and coffee plants, showed similar or identical features to those of B. vietnamiensis TVV75(T). These features include nitrogenase activity with 10 different carbon sources, identical or very similar nifHDK hybridization patterns, very similar protein electrophoregrams, identical amplified 16S rDNA restriction (ARDRA) profiles, and levels of DNA-DNA reassociation higher than 70% with total DNA from strain TVV75(T). Although the ability to fix N(2) is not reported to be a common feature among the known species of the genus Burkholderia, the results obtained show that many diazotrophic Burkholderia isolates analyzed showed phenotypic and genotypic features different from those of the known N(2)-fixing species B. vietnamiensis as well as from those of B. kururiensis, a bacterium identified in the present study as a diazotrophic species. DNA-DNA reassociation assays confirmed the existence of N(2)-fixing Burkholderia species different from B. vietnamiensis. In addition, this study shows the wide geographic distribution and substantial capability of N(2)-fixing Burkholderia spp. for colonizing diverse host plants in distantly separated environments. PMID:11375196

  17. Power plant waste heat utilization in aquaculture. Volume III. Final report, 1 November 1976-1 November 1979

    SciTech Connect

    Farmanfarmaian, A.

    1980-03-01

    This report is part of a three year research study on the constructive use of electric generating station waste heat in cooling water effluents for fish production. It describes procedures and methods for the commercial culture of the giant fresh water shrimp, Macrobrachium rosenbergii, and the rainbow trout, Salmo gairdneri, in the thermal discharge water of the Mercer Power Plant in Trenton, New Jersey. Discharge water from this plant was used in a preliminary assessment of the survival, growth, and food conversion ratio of these species. It was shown that acute or chronic exposure to power plant intake and discharge water; discharge with or without coal particles; and discharge with or without slurry overflow mix does not significantly affect metabolism, short-term survival, growth, or conversion efficiency of shrimp or trout.

  18. Distributed microprocessor control of the heliostat field for the THEMIS power plant

    NASA Astrophysics Data System (ADS)

    Barani-Cabanne, M.-D.

    1984-06-01

    A distributed control system implemented for the heliostats directing sunlight to the power tower aperture of the THEMIS solar electric power plant is detailed. Microprocessors were installed in each heliostat, with operations guided by safety and maximized power delivery requirements, constant communications with a central control computer, and accommodation to experimental operating conditions. THEMIS was operated in parallel with the French electric grid. The microprocessors were programmed to ensure maximized solar energy capture at the tower aperture and to remove the flux during shutdowns. Attention was also given to controlling the flux distribution within the receiver aperture. Fully automated operations could not be realized, so a three-level optimized control hierarchy was defined: the central control computer, a microcomputer controlling groups of heliostats, and individual heliostat microprocessors. Individual heliostats could be taken off-line for maintenance. A bus-based system was devised to route the message traffic among the hierarchical components along paths designed as a Petri grid.

  19. Distribution of tritium in water vapour and precipitation around Wolsung nuclear power plant.

    PubMed

    Chae, Jung-Seok; Lee, Sang-Kuk; Kim, Yongjae; Lee, Jung-Min; Cho, Heung-Joon; Cho, Yong-Woo; Yun, Ju-Yong

    2011-07-01

    The distribution of tritium in water vapour and precipitation with discharge of tritiated water vapour and meteorological factors was studied around the Wolsung nuclear power plant (NPP) site during the period 2004-2008. The tritium concentrations in atmospheric water vapour and precipitation had a temporal variation with relatively high values in the early summer. Spatial distribution of tritium concentrations was affected by various factors such as distance from the NPP site, wind direction, tritium discharge into the atmosphere and atmospheric dispersion factor. The annual mean concentrations of atmospheric HTO and precipitation were correlated with the amount of gaseous tritium released from the Wolsung NPP. The tritium concentrations in precipitation decrease exponentially with an increase of the distance from the Wolsung NPP site.

  20. Spatial distribution of enzyme activities along the root and in the rhizosphere of different plants

    NASA Astrophysics Data System (ADS)

    Razavi, Bahar S.; Zarebanadkouki, Mohsen; Blagodatskaya, Evgenia; Kuzyakov, Yakov

    2015-04-01

    Extracellular enzymes are important for decomposition of many biological macromolecules abundant in soil such as cellulose, hemicelluloses and proteins. Activities of enzymes produced by both plant roots and microbes are the primary biological drivers of organic matter decomposition and nutrient cycling. So far acquisition of in situ data about local activity of different enzymes in soil has been challenged. That is why there is an urgent need in spatially explicit methods such as 2-D zymography to determine the variation of enzymes along the roots in different plants. Here, we developed further the zymography technique in order to quantitatively visualize the enzyme activities (Spohn and Kuzyakov, 2013), with a better spatial resolution We grew Maize (Zea mays L.) and Lentil (Lens culinaris) in rhizoboxes under optimum conditions for 21 days to study spatial distribution of enzyme activity in soil and along roots. We visualized the 2D distribution of the activity of three enzymes:β-glucosidase, leucine amino peptidase and phosphatase, using fluorogenically labelled substrates. Spatial resolution of fluorescent images was improved by direct application of a substrate saturated membrane to the soil-root system. The newly-developed direct zymography shows different pattern of spatial distribution of enzyme activity along roots and soil of different plants. We observed a uniform distribution of enzyme activities along the root system of Lentil. However, root system of Maize demonstrated inhomogeneity of enzyme activities. The apical part of an individual root (root tip) in maize showed the highest activity. The activity of all enzymes was the highest at vicinity of the roots and it decreased towards the bulk soil. Spatial patterns of enzyme activities as a function of distance from the root surface were enzyme specific, with highest extension for phosphatase. We conclude that improved zymography is promising in situ technique to analyze, visualize and quantify

  1. Characteristics of inhalable particulate matter concentration and size distribution from power plants in China

    SciTech Connect

    Honghong Yi; Jiming Hao; Lei Duan; Xinghua Li; Xingming Guo

    2006-09-15

    The collection efficiency of particulate emission control devices (PECDs), particulate matter (PM) emissions, and PM size distribution were determined experimentally at the inlet and outlet of PECDs at five coal-fired power plants. Different boilers, coals, and PECDs are used in these power plants. Measurement in situ was performed by an electrical low-pressure impactor with a sampling system, which consisted of an isokinetic sampler probe, precut cyclone, and two- stage dilution system with a sample line to the instruments. The size distribution was measured over a range from 0.03 to 10 {mu}m. Before and after all of the PECDs, the particle number size distributions display a bimodal distribution. The PM2.5 fraction emitted to atmosphere includes a significant amount of the mass from the coarse particle mode. The controlled and uncontrolled emission factors of total PM, inhalable PM (PM10), and fine PM (PM2.5) were obtained. Electrostatic precipitator (ESP) and baghouse total collection efficiencies are 96.38 99.89% and 99.94%, respectively. The minimum collection efficiency of the ESP and the baghouse both appear in the particle size range of 0.1 1 0 {mu}m. In this size range, ESP and baghouse collection efficiencies are 85.79 98.6% and 99.54%. Real- time measurement shows that the mass and number concentration of PM10 will be greatly affected by the operating conditions of the PECDs. The number of emitted particles increases with increasing boiler load level because of higher combustion temperature. During test run periods, the data reproducibility is satisfactory. 19 refs., 11 figs., 6 tabs.

  2. The mechanism by which an asymmetric distribution of plant growth hormone is attained

    NASA Astrophysics Data System (ADS)

    Bandurski, Robert S.; Schulze, Aga; Jensen, Philip; Desrosiers, Mark; Epel, Bernard; Kowalczyk, Stanley

    Zea mays (sweet corn) seedlings attain an asymmetric distribution of the growth hormone indole-3-acetic acid (IAA) within 3 minutes following a gravity stimulus. Both free and esterified IAA (that is total IAA) accumulate to a greater extent in the lower half of the mesocotyl cortex of a horizontally placed seedling than in the upper half. Thus, changes in the ratio of free IAA to ester IAA cannot account for the asymmetric distribution. Our studies demonstrate there is no de novo synthesis of IAA in young seedlings. We conclude that asymmetric IAA distribution is attained by a gravity-induced, potential-regulated gating of the movement of IAA from kernel to shoot and from stele to cortex. As a working theory, which we call the Potential Gating Theory, we propose that perturbation of the plant's bioelectric field, induced by gravity, causes opening and closing of transport channels in the plasmodesmata connecting the vascular stele to the surrounding cortical tissues. This results in asymmetric growth hormone distribution which results in the asymmetric growth characteristic of the gravitropic response.

  3. Type III extended pilot-plant evaluation of molten H-Coal liquefaction residue. Gasification of residual-materials from coal liquefaction

    SciTech Connect

    Wu, C.M.; Robin, A.M.

    1982-12-01

    A Type III extended pilot plant evaluation of molten H-Coal liquefaction residue, which was obtained from the liquefaction of Illinois No. 6 coal at the H-Coal liquefaction process pilot plant at Catlettsburg, Kentucky, was successfully completed at Texaco's Montebello Research Laboratory. Approximately 55 tons of residue were gasified during five runs which were carried out at 750 to 790 psig in the Texaco pilot plant residue gasifier. The steam-to-residue ratio and the gasifier temperature were varied to determine optimum operating conditions. The runs lasted from 3.5 hours to 64 hours, and a total 138 hours of on-stream time was accumulated. This work was authorized by DOE Deliver Order Number 7 under DOE contract EX-76-C-01-2247 and amendment DEAC-01-76ET-10137. It is part of a continuing project to evaluate residual materials from various DOE sponsored coal liquefaction projects to determine their suitability for conversion to hydrogen using one of the Texaco gasification processes.

  4. Distribution of 45S rDNA sites in chromosomes of plants: Structural and evolutionary implications

    PubMed Central

    2012-01-01

    Background 45S rDNA sites are the most widely documented chromosomal regions in eukaryotes. The analysis of the distribution of these sites along the chromosome in several genera has suggested some bias in their distribution. In order to evaluate if these loci are in fact non-randomly distributed and what is the influence of some chromosomal and karyotypic features on the distribution of these sites, a database was built with the position and number of 45S rDNA sites obtained by FISH together with other karyotypic data from 846 plant species. Results In angiosperms the most frequent numbers of sites per diploid karyotype were two and four, suggesting that in spite of the wide dispersion capacity of these sequences the number of rDNA sites tends to be restricted. The sites showed a preferential distribution on the short arms, mainly in the terminal regions. Curiously, these sites were frequently found on the short arms of acrocentric chromosomes where they usually occupy the whole arm. The trend to occupy the terminal region is especially evident in holokinetic chromosomes, where all of them were terminally located. In polyploids there is a trend towards reduction in the number of sites per monoploid complement. In gymnosperms, however, the distribution of rDNA sites varied strongly among the sampled families. Conclusions The location of 45S rDNA sites do not vary randomly, occurring preferentially on the short arm and in the terminal region of chromosomes in angiosperms. The meaning of this preferential location is not known, but some hypotheses are considered and the observed trends are discussed. PMID:23181612

  5. Failure mode analysis for lime/limestone FGD system. Volume III. Plant profiles. Part 1 of 3

    SciTech Connect

    Kenney, S.M.; Rosenberg, H.S.; Nilsson, L.I.O.; Oxley, J.H.

    1984-08-01

    This volume contains plant profiles for: Petersburg 3; Hawthorn 3, 4; La Cygne 1; Jeffry 1, 2; Lawrence 4, 5; Green River 1-3; Cane Run 4, 5; Mill Creek 1, 3; Paddy's Run 6; Clay Boswell 4; Milton R. Young 2; Pleasants 1, 2; and Colstrip 1, 2. (DLC)

  6. Waste Isolation Pilot Plant. Ecosystem studies at the Los Medanos Site Eddy County, New Mexico. Volume I of III

    SciTech Connect

    Braswell, J.; Hart, J.S.

    1982-03-01

    This document summarizes the results of biological studies conducted at the Los Medanos site in southeastern New Mexico during 1981. Complete study reports prepared by the principal investigators are included as an appendix to this document. Biological studies have been underway at the Los Medanos site since 1975; this work constitutes a portion of the site characterization effort the US Department of energy (DOE) is pursuing in preparation for the development of the Waste Isolation Pilot Plant (WIPP). WIPP is to be a research and development facility to demonstrate the safe disposal of radioactive waste material produced through national defense activities. The appendix contains the following: Avifauna Baseline Studies at the Los Medanos Site, Southeastern New Mexico; Aquatic Ecosystems of the Lower Pecos Drainage in New Mexico; Floristic Studies at the Los Medanos Site; Los Medanos Project - Soil Studies; Arthropod and Decomposition Studies at the WIPP Site; Ecology of Amphibians, Reptiles, and Mammals at the Los Medanos Waste Isolation Pilot Plant (WIPP) Project Area of New Mexico; Vertebrate Ecology at the Los Medanos Waste Isolation Pilot Plant, New Mexico; and Statistical Evaluation of Plant Density Data Collected at the Los Medanos Site, New Mexico (1978-1980).

  7. Statistical Studies on Protein Polymorphism in Natural Populations. III. Distribution of Allele Frequencies and the Number of Alleles per Locus

    PubMed Central

    Chakraborty, Ranajit; Fuerst, Paul A.; Nei, Masatoshi

    1980-01-01

    With the aim of understanding the mechanism of maintenance of protein polymorphism, we have studied the properties of allele frequency distribution and the number of alleles per locus, using gene-frequency data from a wide range of organisms (mammals, birds, reptiles, amphibians, Drosophila and non-Drosophila invertebrates) in which 20 or more loci with at least 100 genes were sampled. The observed distribution of allele frequencies was U-shaped in all of the 138 populations (mostly species or subspecies) examined and generally agreed with the theoretical distribution expected under the mutation-drift hypothesis, though there was a significant excess of rare alleles (gene frequency, 0 ∼ 0.05) in about a quarter of the populations. The agreement between the mutation-drift theory and observed data was quite satisfactory for the numbers of polymorphic (gene frequency, 0.05 ∼ 0.95) and monomorphic (0.95 ∼ 1.0) alleles.—The observed pattern of allele-frequency distribution was incompatible with the prediction from the overdominance hypothesis. The observed correlations of the numbers of rare alleles, polymorphic alleles and monomorphic alleles with heterozygosity were of the order of magnitude that was expected under the mutation-drift hypothesis. Our results did not support the view that intracistronic recombination is an important source of genetic variation. The total number of alleles per locus was positively correlated with molecular weight in most of the species examined, and the magnitude of the correlation was consistent with the theoretical prediction from mutation-drift hypothesis. The correlation between molecular weight and the number of alleles was generally higher than the correlation between molecular weight and heterozygosity, as expected. PMID:17249018

  8. Tracing subsoil organic matter compositional changes by radiocarbon and plant leaf wax distributional changes

    NASA Astrophysics Data System (ADS)

    John, Stephan; Angst, Gerrit; Mueller, Carsten W.; Heinze, Stefanie; Marschner, Bernd; Rethemeyer, Janet

    2014-05-01

    The carbon pool in subsoils is thought to be considerably larger than in the upper 30 cm. However, factors like turnover, stabilization and distribution of organic matter (OM) are less well understood than in topsoils. The investigation of changes in OM composition with depth enables a better understanding of the peculiarity of subsoil OM in contrast to the already extensively studied topsoil OM. Analysis of long chained n-alkanes and n-fatty acids in soil profiles sampled in high resolution, combined with radiocarbon data of bulk soil, is a tool to demonstrate spatial distribution and the degradation of plant leaf wax-derived material as a defined source of soil organic. We analysed the OM in 3.15 m long soil transects under an even aged European beech (Fagus sylvatica L.) forest in Northern Germany (Grinderwald, Lower Saxony) for lipid and radiocarbon analysis. Samples were taken from a grid raster with eight sampling points increasing in distance to the main tree (45cm grid dimension) and from five depths (10, 35, 60, 85, 110 cm) resulting 40 samples per transect. Organic carbon contents in the podzolic Cambisol decrease from 1.69 % in the A-horizon to 0.02 % in the C-horizon at 110 cm depth. The distribution of organic carbon contents shows no significant trend with increasing distance to the beeches in all transects. We compare the distribution of long-chain n-alkanes (C27, C29 and C31) and n-fatty acids (>C20), known as components mainly derived from leaf waxes of higher plants, in the different transect/depth intervals. Distributional and quantitative changes in the transects, combined with bulk soil 14C-analyses, reflecting apparent mean residence time of OM, are used to identify how fast OM is degraded from surface to subsoil horizons. Furthermore, spatial OM heterogeneity in the transects is investigated. We expect a more significant heterogeneity in the lipid distribution and nearly similar decreasing contents for n-alkanes as well as n-fatty acids

  9. Saline or plant-incorporated methylmercury effects on distribution, demethylation, and blood parameters in rats

    SciTech Connect

    Czuba, M.; Komsta-Szumska, E.; Mortimer, D.C.; Champagne, C.

    1987-03-01

    The influence of diet is recognized as a significant factor in the expression of toxicity. This applies particularly to toxins like methylmercury (MeHg) which are metabolically incorporated into growing food plants and biotransformed within the plant before ingestion. Methylmercury in this form may influence the early physiological and biochemical events which lead to development of toxicity. In a previous study, a single dose of plant-incorporated methylmercury (MeHg) had a different route of distribution and accumulation in rat organs after 48 h than an equivalent dose of saline MeHg with the greatest accumulation being in red blood cells. Creatine, an important storage form of high energy phosphate in muscles is a primary indicator of erythropoietic dynamics under hypoxia, a sensitive indicator of hemolytic disease, red blood cell aging and impaired marrow efficiency. Since changes in creatine levels occur sooner than changes in other blood parameters, itself being neither synthesized nor metabolized by red blood cells, it can be used as a sensitive indicator of toxicity. The present work investigates the difference in a longer term, multiple-dose regime of saline or bean-incorporated MeHg ingestion with special attention being given to various blood parameters.

  10. Treating Stormwater with Green Infrastructure: Plants, Residence Time Distributions, and the Removal of Fecal Indicator Bacteria

    NASA Astrophysics Data System (ADS)

    Parker, E.; Grant, S. B.; Rippy, M.; Winfrey, B.; Mehring, A.

    2015-12-01

    In many cities, green infrastructure is increasingly used to capture and treat stormwater runoff, due to the many opportunities these systems afford for protecting receiving water quality and ecology while mitigating water scarcity. Here, we focus on how plants affect the removal of fecal indicator bacteria (FIB) in newly-constructed stormwater biofilters, a type of green infrastructure consisting of unconsolidated granular media containing one or more plant species. Input-response experiments were carried out using both non-reactive (salt) and reactive (sewage) tracers on six laboratory-scale (~1m long by 24 cm diameter) biofilters, half of which were planted with the sedge Carex appressa (treatment replicates) and half of which were unplanted (control replicates). C. appressa modifies the residence time distribution (RTD) in a biofilter by creating preferential flow paths along which water and mass can move quickly, but does not appear to alter the intrinsic rate at which FIB are removed. Thus, the "green" component of green infrastructure can alter pollutant removal by changing the RTD, with or without a concomitant change in pollutant reactivity.

  11. Geographic distribution and host plants of Raoiella indica and associated mite species in northern Venezuela.

    PubMed

    Vásquez, Carlos; de Moraes, Gilberto J

    2013-05-01

    The red palm mite (RPM), Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive pest in the New World, where it is currently considered a serious threat to coconut and banana crops. It was first reported from northern Venezuela in 2007. To determine its current distribution in this country, surveys were carried out from October 2008 to April 2010 on coconut (Cocos nucifera L.), banana (Musa spp.), ornamental plants and weeds in northern Venezuela. Higher population levels of RPM were registered on commercial coconut farms in Falcón and Sucre states but also on other plant species naturally growing along the coastal line in Anzoategui, Aragua, Carabobo, Monagas and Nueva Esparta states. Out of 34 botanical species evaluated, all RPM stages were observed only on eight arecaceous, one musaceous and one streliziaceous species, indicating that the pest developed and reproduced only on these plants. Mite specimens found on weeds were considered spurious events, as immature stages of the pest were never found on these. Amblyseius largoensis (Muma) (Acari: Phytoseiidae) was the most frequent predatory mite associated with RPM in all sampling sites. The results indicate that RPM has spread to extensive areas of northern Venezuela since its initial detection in Güiria, Sucre state. Considering the report of this pest mite in northern Brazil in the late 2009, additional samplings in southern Venezuela should be carried out, to evaluate the possible presence of RPM also in that region. PMID:23065034

  12. Distribution of circular proteins in plants: large-scale mapping of cyclotides in the Violaceae

    PubMed Central

    Burman, Robert; Yeshak, Mariamawit Y.; Larsson, Sonny; Craik, David J.; Rosengren, K. Johan; Göransson, Ulf

    2015-01-01

    During the last decade there has been increasing interest in small circular proteins found in plants of the violet family (Violaceae). These so-called cyclotides consist of a circular chain of approximately 30 amino acids, including six cysteines forming three disulfide bonds, arranged in a cyclic cystine knot (CCK) motif. In this study we map the occurrence and distribution of cyclotides throughout the Violaceae. Plant material was obtained from herbarium sheets containing samples up to 200 years of age. Even the oldest specimens contained cyclotides in the preserved leaves, with no degradation products observable, confirming their place as one of the most stable proteins in nature. Over 200 samples covering 17 of the 23–31 genera in Violaceae were analyzed, and cyclotides were positively identified in 150 species. Each species contained a unique set of between one and 25 cyclotides, with many exclusive to individual plant species. We estimate the number of different cyclotides in the Violaceae to be 5000–25,000, and propose that cyclotides are ubiquitous among all Violaceae species. Twelve new cyclotides from six phylogenetically dispersed genera were sequenced. Furthermore, the first glycosylated derivatives of cyclotides were identified and characterized, further increasing the diversity and complexity of this unique protein family. PMID:26579135

  13. Virulence of Erwinia amylovora, a prevalent apple pathogen: Outer membrane proteins and type III secreted effectors increase fitness and compromise plant defenses.

    PubMed

    Holtappels, Michelle; Noben, Jean-Paul; Valcke, Roland

    2016-09-01

    Until now, no data are available on the outer membrane (OM) proteome of Erwinia amylovora, a Gram-negative plant pathogen, causing fire blight in most of the members of the Rosaceae family. Since the OM forms the interface between the bacterial cell and its environment it is in direct contact with the host. Additionally, the type III secretion system, embedded in the OM, is a pathogenicity factor of E. amylovora. To assess the influence of the OM composition and the secretion behavior on virulence, a 2D-DIGE analysis and gene expression profiling were performed on a high and lower virulent strain, both in vitro and in planta. Proteome data showed an increase in flagellin for the lower virulent strain in vitro, whereas, in planta several interesting proteins were identified as being differently expressed between both the strains. Further, gene expression of nearly all type III secreted effectors was elevated for the higher virulent strain, both in vitro and in planta. As a first, we report that several characteristics of virulence can be assigned to the OM proteome. Moreover, we demonstrate that secreted proteins prove to be the important factors determining differences in virulence between the strains, otherwise regarded as homogeneous on a genome level. PMID:27345300

  14. Removal of As(III) and As(V) using iron-rich sludge produced from coal mine drainage treatment plant.

    PubMed

    Yang, Jung-Seok; Kim, Young-Soo; Park, Sang-Min; Baek, Kitae

    2014-09-01

    To test the feasibility of the reuse of iron-rich sludge (IRS) produced from a coal mine drainage treatment plant for removing As(III) and As(V) from aqueous solutions, we investigated various parameters, such as contact time, pH, initial As concentration, and competing ions, based on the IRS characterization. The IRS consisted of goethite and calcite, and had large surface area and small particles. According to energy dispersive X-ray spectroscopy mapping results, As was mainly removed by adsorption onto iron oxides. The adsorption kinetic studies showed that nearly 70 % adsorption of As was achieved within 1 h, and the pseudo-second-order model well explained As sorption on the IRS. The adsorption isotherm results agreed with the Freundlich isotherm model, and the maximum adsorption capacities for As(III) and As(V) were 66.9 and 21.5 mg/g, respectively, at 293 K. In addition, the adsorption showed the endothermic character. At high pH or in the presence of phosphate, the adsorption of As was decreased. When the desorption experiment was conducted to reuse the IRS, 85 % As was desorbed with 1.0 N NaOH. In the column experiment, adsorbed As in real acid mine drainage was 43 % of the maximum adsorbed amount of As in the batch test. These results suggested that the IRS is an effective adsorbent for As and can be effectively applied for the removal of As in water and wastewater.

  15. A Novel Class of Plant Type III Polyketide Synthase Involved in Orsellinic Acid Biosynthesis from Rhododendron dauricum

    PubMed Central

    Taura, Futoshi; Iijima, Miu; Yamanaka, Eriko; Takahashi, Hironobu; Kenmoku, Hiromichi; Saeki, Haruna; Morimoto, Satoshi; Asakawa, Yoshinori; Kurosaki, Fumiya; Morita, Hiroyuki

    2016-01-01

    Rhododendron dauricum L. produces daurichromenic acid, the anti-HIV meroterpenoid consisting of sesquiterpene and orsellinic acid (OSA) moieties. To characterize the enzyme responsible for OSA biosynthesis, a cDNA encoding a novel polyketide synthase (PKS), orcinol synthase (ORS), was cloned from young leaves of R. dauricum. The primary structure of ORS shared relatively low identities to those of PKSs from other plants, and the active site of ORS had a unique amino acid composition. The bacterially expressed, recombinant ORS accepted acetyl-CoA as the preferable starter substrate, and produced orcinol as the major reaction product, along with four minor products including OSA. The ORS identified in this study is the first plant PKS that generates acetate-derived aromatic tetraketides, such as orcinol and OSA. Interestingly, OSA production was clearly enhanced in the presence of Cannabis sativa olivetolic acid cyclase, suggesting that the ORS is involved in OSA biosynthesis together with an unidentified cyclase in R. dauricum. PMID:27729920

  16. Preliminary design of the Carrisa Plains solar central receiver power plant. Volume III, Book 1. Design description

    SciTech Connect

    Not Available

    1983-12-31

    The design of the 30 MWe central receiver solar power plant to be located at Carrisa Plains, San Luis Obispo County, California, is summarized. The plant uses a vertical flat-panel (billboard solar receiver located at the top of a tower to collect solar energy redirected by approximately 1900 heliostats located to the north of the tower. The solar energy is used to heat liquid sodium pumped from ground level from 610 to 1050/sup 0/F. The power conversion system is a non-reheat system, cost-effective at this size level, and designed for high-efficiency performance in an application requiring daily startup. Successful completion of this project will lead to power generation starting in 1986. This report discusses in detail the design of the collector system, heat transport system, thermal storage subsystem, heat transport loop, steam generation subsystem, electrical, instrumentation, and control systems, power conversion system, master control system, and balance of plant. The performance, facility cost estimate and economic analysis, and development plan are also discussed.

  17. INTELLIGENT MONITORING SYSTEM WITH HIGH TEMPERATURE DISTRIBUTED FIBEROPTIC SENSOR FOR POWER PLANT COMBUSTION PROCESSES

    SciTech Connect

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2003-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, the efforts focused on developing an innovative high temperature distributed fiber optic sensor by fabricating in-fiber gratings in single crystal sapphire fibers. So far, our major accomplishments include: Successfully grown alumina cladding layers on single crystal sapphire fibers, successfully fabricated in-fiber gratings in single crystal sapphire fibers, and successfully developed a high temperature distributed fiber optic sensor. Under Task 2, the emphasis has been on putting into place a computational capability for simulation of combustors. A PC workstation was acquired with dual Xeon processors and sufficient memory to support 3-D calculations. An existing license for Fluent software was expanded to include two PC processes, where the existing license was for a Unix workstation. Under Task 3, intelligent state estimation theory is being developed which will map the set of 1D (located judiciously within a 3D environment) measurement data into a 3D temperature profile. This theory presents a semigroup

  18. Climate change may alter breeding ground distributions of eastern migratory monarchs (Danaus plexippus) via range expansion of Asclepias host plants.

    PubMed

    Lemoine, Nathan P

    2015-01-01

    Climate change can profoundly alter species' distributions due to changes in temperature, precipitation, or seasonality. Migratory monarch butterflies (Danaus plexippus) may be particularly susceptible to climate-driven changes in host plant abundance or reduced overwintering habitat. For example, climate change may significantly reduce the availability of overwintering habitat by restricting the amount of area with suitable microclimate conditions. However, potential effects of climate change on monarch northward migrations remain largely unknown, particularly with respect to their milkweed (Asclepias spp.) host plants. Given that monarchs largely depend on the genus Asclepias as larval host plants, the effects of climate change on monarch northward migrations will most likely be mediated by climate change effects on Asclepias. Here, I used MaxEnt species distribution modeling to assess potential changes in Asclepias and monarch distributions under moderate and severe climate change scenarios. First, Asclepias distributions were projected to extend northward throughout much of Canada despite considerable variability in the environmental drivers of each individual species. Second, Asclepias distributions were an important predictor of current monarch distributions, indicating that monarchs may be constrained as much by the availability of Asclepias host plants as environmental variables per se. Accordingly, modeling future distributions of monarchs, and indeed any tightly coupled plant-insect system, should incorporate the effects of climate change on host plant distributions. Finally, MaxEnt predictions of Asclepias and monarch distributions were remarkably consistent among general circulation models. Nearly all models predicted that the current monarch summer breeding range will become slightly less suitable for Asclepias and monarchs in the future. Asclepias, and consequently monarchs, should therefore undergo expanded northern range limits in summer months

  19. Climate change may alter breeding ground distributions of eastern migratory monarchs (Danaus plexippus) via range expansion of Asclepias host plants.

    PubMed

    Lemoine, Nathan P

    2015-01-01

    Climate change can profoundly alter species' distributions due to changes in temperature, precipitation, or seasonality. Migratory monarch butterflies (Danaus plexippus) may be particularly susceptible to climate-driven changes in host plant abundance or reduced overwintering habitat. For example, climate change may significantly reduce the availability of overwintering habitat by restricting the amount of area with suitable microclimate conditions. However, potential effects of climate change on monarch northward migrations remain largely unknown, particularly with respect to their milkweed (Asclepias spp.) host plants. Given that monarchs largely depend on the genus Asclepias as larval host plants, the effects of climate change on monarch northward migrations will most likely be mediated by climate change effects on Asclepias. Here, I used MaxEnt species distribution modeling to assess potential changes in Asclepias and monarch distributions under moderate and severe climate change scenarios. First, Asclepias distributions were projected to extend northward throughout much of Canada despite considerable variability in the environmental drivers of each individual species. Second, Asclepias distributions were an important predictor of current monarch distributions, indicating that monarchs may be constrained as much by the availability of Asclepias host plants as environmental variables per se. Accordingly, modeling future distributions of monarchs, and indeed any tightly coupled plant-insect system, should incorporate the effects of climate change on host plant distributions. Finally, MaxEnt predictions of Asclepias and monarch distributions were remarkably consistent among general circulation models. Nearly all models predicted that the current monarch summer breeding range will become slightly less suitable for Asclepias and monarchs in the future. Asclepias, and consequently monarchs, should therefore undergo expanded northern range limits in summer months

  20. The human red cell voltage-dependent cation channel. Part III: Distribution homogeneity and pH dependence.

    PubMed

    Bennekou, P; Barksmann, T L; Christophersen, P; Kristensen, B I

    2006-01-01

    The homogeneity of the distribution of the non-selective voltage-dependent cation channel (the NSVDC channel) in the human erythrocyte, and the pH dependence was investigated. Activation of this channel caused a uniform cellular dehydration, which was characterized by the changes in the erythrocyte osmotic resistance profiles: after 1/2 h of activation, the osmolarity at 50% hemolysis changed from 73 mM (control) to 34 mM NaCl, corresponding to 0.48% and 0.21% NaCl respectively. Unchanging standard deviations show participation of the entire erythrocyte population, which implies an even distribution of the NSVDC channel among the cells. Inactivation of the NSVDC channel with N-ethyl-maleimide (NEM) or blocking of the Cl(-) conductance with NS1652 retarded the migration of the resistance profiles towards lower osmolarities. The NSVDC channel activation was blocked by a decrease of the intracellular -- but not the extracellular -- pH. The apparent pK(A) value for the effect was estimated to be 6.5, and the specific histidine reagent 2.4'-dibromoacetophenone (DBAB) inactivated the NSVDC channel. PMID:16376587

  1. Charge distribution as a tool to investigate structural details. III. Extension to description in terms of anion-centred polyhedra.

    PubMed

    Eon, Jean-Guillaume; Nespolo, Massimo

    2015-02-01

    The charge distribution (CHARDI) method is a self-consistent generalization of Pauling's concept of bond strength which does not make use of empirical parameters but exploits the experimental geometry of the coordination polyhedra building a crystal structure. In the two previous articles of this series [Nespolo et al. (1999). Acta Cryst. B55, 902-916; Nespolo et al. (2001). Acta Cryst. B57, 652-664], we have presented the features and advantages of this approach and its extension to distorted and heterovalent polyhedra and to hydrogen bonds. In this third article we generalize CHARDI to structures based on anion-centred polyhedra, which have drawn attention in recent years, and we show that computations based on both descriptions can be useful to obtain a deeper insight into the structural details, in particular for mixed-valence compounds where CHARDI is able to give precise indications on the statistical distribution of atoms with different oxidation number. A graph-theoretical description of the structures rationalizes and gives further support to the conclusions obtained via the CHARDI approach.

  2. Fate and distribution of nitrogen in soil and plants irrigated with landfill leachate.

    PubMed

    Cheng, C Y; Chu, L M

    2011-06-01

    Landfill leachate contains a high concentration of ammoniacal substances which can be a potential supply of N for plants. A bioassay was conducted using seeds of Brassica chinensis and Lolium perenne to evaluate the phytotoxicity of the leachate sample. A soil column experiment was then carried out in a greenhouse to study the effect of leachate on plant growth. Two grasses (Paspalum notatum and Vetiver zizanioides) and two trees (Hibiscus tiliaceus and Litsea glutinosa) were irrigated with leachate at the EC50 levels for 12 weeks. Their growth performance and the distribution of N were examined and compared with columns applied with chemical fertilizer. With the exception of P. notatum, plants receiving leachate and fertilizer grew better than those receiving water alone. The growth of L. glutinosa and V. zizanioides with leachate irrigation did not differ significantly from plants treated with fertilizer. Leachate irrigation significantly increased the levels of NH(x)-N in soil. Although NO(x)-N was below 1 mg NL(-1) in the leachate sample, the soil NO(x)-N content increased by 9-fold after leachate irrigation, possibly as a result of nitrification. Leachate irrigation at EC50 provided an N input of 1920 kg N ha(-1) over the experimental period, during which up to 1050 kg N ha(-1) was retained in the soil and biomass, depending on the type of vegetation. The amount of nutrient added seems to exceed beyond the assimilative capability. Practitioners should be aware of the possible consequence of N saturation when deciding the application rate if leachate irrigation is aimed for water reuse.

  3. Invasiveness of plant pathogens depends on the spatial scale of host distribution.

    PubMed

    Mikaberidze, Alexey; Mundt, Christopher C; Bonhoeffer, Sebastian

    2016-06-01

    Plant diseases often cause serious yield losses in agriculture. A pathogen's invasiveness can be quantified by the basic reproductive number, R₀. Since pathogen transmission between host plants depends on the spatial separation between them, R₀ is strongly influenced by the spatial scale of the host distribution. We present a proof of principle of a novel approach to estimate the basic reproductivenumber, R₀, of plant pathogens as a function of the size of a field planted with crops and its aspect ratio. This general approach is based on a spatially explicit population dynamical model. The basic reproductive number was found to increase with the field size at small field sizes and to saturate to a constant value at large field sizes. It reaches amaximum in square fields and decreases as the field becomes elongated. This pattern appears to be quite general: it holds for dispersal kernels that decrease exponentially or faster, as well as for fat-tailed dispersal kernels that decrease slower than exponential (i.e., power-law kernels). We used this approach to estimate R₀ in wheat stripe rust(an important disease caused by Puccinia striiformis), where we inferred both the transmission rates and the dispersal kernels from the measurements of disease gradients. For the two largest datasets, we estimated R₀ of P. striiformis in the limit of large fields to be of the order of 30. We found that the spatial extent over which R₀ changes strongly is quite fine-scaled (about 30 m of the linear extension of the field). Our results indicate that in order to optimize the spatial scale of deployment of fungicides or host resistances, the adjustments should be made at a fine spatial scale. We also demonstrated how the knowledge of the spatial dependence of R₀ can improve recommendations with regard to fungicide treatment. PMID:27509761

  4. Type III secretion system and virulence markers highlight similarities and differences between human- and plant-associated pseudomonads related to Pseudomonas fluorescens and P. putida.

    PubMed

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick; Lemanceau, Philippe; Latour, Xavier

    2015-04-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens.

  5. Type III secretion system and virulence markers highlight similarities and differences between human- and plant-associated pseudomonads related to Pseudomonas fluorescens and P. putida.

    PubMed

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick; Lemanceau, Philippe; Latour, Xavier

    2015-04-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens. PMID:25636837

  6. Type III Secretion System and Virulence Markers Highlight Similarities and Differences between Human- and Plant-Associated Pseudomonads Related to Pseudomonas fluorescens and P. putida

    PubMed Central

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick

    2015-01-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens. PMID:25636837

  7. Back to Gondwanaland: can ancient vicariance explain (some) Indian Ocean disjunct plant distributions?

    PubMed

    Pirie, Michael D; Litsios, Glenn; Bellstedt, Dirk U; Salamin, Nicolas; Kissling, Jonathan

    2015-06-01

    Oceans, or other wide expanses of inhospitable environment, interrupt present day distributions of many plant groups. Using molecular dating techniques, generally incorporating fossil evidence, we can estimate when such distributions originated. Numerous dating analyses have recently precipitated a paradigm shift in the general explanations for the phenomenon, away from older geological causes, such as continental drift, in favour of more recent, long-distance dispersal (LDD). For example, the 'Gondwanan vicariance' scenario has been dismissed in various studies of Indian Ocean disjunct distributions. We used the gentian tribe Exaceae to reassess this scenario using molecular dating with minimum (fossil), maximum (geological), secondary (from wider analyses) and hypothesis-driven age constraints. Our results indicate that ancient vicariance cannot be ruled out as an explanation for the early origins of Exaceae across Africa, Madagascar and the Indian subcontinent unless a strong assumption is made about the maximum age of Gentianales. However, both the Gondwanan scenario and the available evidence suggest that there were also several, more recent, intercontinental dispersals during the diversification of the group.

  8. Back to Gondwanaland: can ancient vicariance explain (some) Indian Ocean disjunct plant distributions?

    PubMed

    Pirie, Michael D; Litsios, Glenn; Bellstedt, Dirk U; Salamin, Nicolas; Kissling, Jonathan

    2015-06-01

    Oceans, or other wide expanses of inhospitable environment, interrupt present day distributions of many plant groups. Using molecular dating techniques, generally incorporating fossil evidence, we can estimate when such distributions originated. Numerous dating analyses have recently precipitated a paradigm shift in the general explanations for the phenomenon, away from older geological causes, such as continental drift, in favour of more recent, long-distance dispersal (LDD). For example, the 'Gondwanan vicariance' scenario has been dismissed in various studies of Indian Ocean disjunct distributions. We used the gentian tribe Exaceae to reassess this scenario using molecular dating with minimum (fossil), maximum (geological), secondary (from wider analyses) and hypothesis-driven age constraints. Our results indicate that ancient vicariance cannot be ruled out as an explanation for the early origins of Exaceae across Africa, Madagascar and the Indian subcontinent unless a strong assumption is made about the maximum age of Gentianales. However, both the Gondwanan scenario and the available evidence suggest that there were also several, more recent, intercontinental dispersals during the diversification of the group. PMID:26063747

  9. Back to Gondwanaland: can ancient vicariance explain (some) Indian Ocean disjunct plant distributions?

    PubMed Central

    Pirie, Michael D.; Litsios, Glenn; Bellstedt, Dirk U.; Salamin, Nicolas; Kissling, Jonathan

    2015-01-01

    Oceans, or other wide expanses of inhospitable environment, interrupt present day distributions of many plant groups. Using molecular dating techniques, generally incorporating fossil evidence, we can estimate when such distributions originated. Numerous dating analyses have recently precipitated a paradigm shift in the general explanations for the phenomenon, away from older geological causes, such as continental drift, in favour of more recent, long-distance dispersal (LDD). For example, the ‘Gondwanan vicariance’ scenario has been dismissed in various studies of Indian Ocean disjunct distributions. We used the gentian tribe Exaceae to reassess this scenario using molecular dating with minimum (fossil), maximum (geological), secondary (from wider analyses) and hypothesis-driven age constraints. Our results indicate that ancient vicariance cannot be ruled out as an explanation for the early origins of Exaceae across Africa, Madagascar and the Indian subcontinent unless a strong assumption is made about the maximum age of Gentianales. However, both the Gondwanan scenario and the available evidence suggest that there were also several, more recent, intercontinental dispersals during the diversification of the group. PMID:26063747

  10. Colloidal organic matter from wastewater treatment plant effluents: Characterization and role in metal distribution.

    PubMed

    Worms, Isabelle A M; Al-Gorani Szigeti, Zsofia; Dubascoux, Stephane; Lespes, Gaetane; Traber, Jacqueline; Sigg, Laura; Slaveykova, Vera I

    2010-01-01

    Colloidal organic matter from wastewater treatment plants was characterized and examined with respect to its role in metal distribution by using tangential flow ultrafiltration, liquid chromatography coupled with organic carbon and UV detectors, and an asymmetrical flow field-flow fractionation (AFlFFF) multidetection platform. Results revealed that a humic-like fraction of low aromaticity with an average molar mass ranging from 1600 to 2600Da was the main colloidal component. High molar mass fractions (HMM), with molar mass ranges between 20 and 200kDa, were present in lower proportions. Ag, Cd, Cu, Cr, Mn and Zn were found mainly in the dissolved phase (<0.45microm) and their distribution between colloidal and truly dissolved fractions was strongly influenced by the distribution of dissolved organic carbon. AFlFFF coupled to ICP-MS showed that Ag, Cd, Cu, Cr, Mn and Zn associate to the low molar mass fraction of the colloidal pool, whereas Al, Fe and Pb were equally bound to low and high molar mass fractions. PMID:19836819

  11. Predictors, spatial distribution, and occurrence of woody invasive plants in subtropical urban ecosystems.

    PubMed

    Staudhammer, Christina L; Escobedo, Francisco J; Holt, Nathan; Young, Linda J; Brandeis, Thomas J; Zipperer, Wayne

    2015-05-15

    We examined the spatial distribution, occurrence, and socioecological predictors of woody invasive plants (WIP) in two subtropical, coastal urban ecosystems: San Juan, Puerto Rico and Miami-Dade, United States. These two cities have similar climates and ecosystems typical of subtropical regions but differ in socioeconomics, topography, and urbanization processes. Using permanent plot data, available forest inventory protocols and statistical analyses of geographic and socioeconomic spatial predictors, we found that landscape level distribution and occurrence of WIPs was not clustered. We also characterized WIP composition and occurrence using logistic models, and found they were strongly related to the proportional area of residential land uses. However, the magnitude and trend of increase depended on median household income and grass cover. In San Juan, WIP occurrence was higher in areas of high residential cover when incomes were low or grass cover was low, whereas the opposite was true in Miami-Dade. Although Miami-Dade had greater invasive shrub cover and numbers of WIP species, San Juan had far greater invasive tree density, basal area and crown cover. This study provides an approach for incorporating field and available census data in geospatial distribution models of WIPs in cities throughout the globe. Findings indicate that identifying spatial predictors of WIPs depends on site-specific factors and the ecological scale of the predictor. Thus, mapping protocols and policies to eradicate urban WIPs should target indicators of a relevant scale specific to the area of interest for their improved and proactive management.

  12. A meteoroid stream survey using the Canadian Meteor Orbit Radar - III. Mass distribution indices of six major meteor showers

    NASA Astrophysics Data System (ADS)

    Blaauw, R. C.; Campbell-Brown, M. D.; Weryk, R. J.

    2011-07-01

    The mass distribution index of the Geminid, Quadrantid, Arietid, Eta Aquariid, Orionid and South Delta Aquariid meteor showers have been measured using data from 2007 to 2010 from the Canadian Meteor Orbit Radar (CMOR). Single-station data from the 29.85-MHz system were used to find mass index as a function of solar longitude, and to compare separate years of showers. The variation in mass index with solar longitude can provide information on the structure of the stream and how the structure changes with time. The Geminids and Quadrantids were the most prominent showers seen by CMOR, and had peak mass indices of 1.65 and 1.55, respectively. They had clear, strong peaks and little year-to-year variation. The other showers had slightly higher peak mass indices and a greater variability, even though a more sporadic contamination, which might have affected the results.

  13. [Effect of polychlorinated biphenyls in the rat. III - PCB distribution, storage and elimination relation time (author's transl)].

    PubMed

    Narbonne, J F; Gillet, G; Daubeze, M

    1978-07-01

    The study of accumulation and elimination of Phenoclor DP6 (a commercial PCB mixture) was carried out in three experiments : 1) Rats were fed diet containing 100 ppm of DP6 and were sacrificed after 1, 3, 8, 15 and 30 days. 2) Rats fed DP6 diet during 15 days were subsequently fed with a control diet and sacrificed 8, 15, 52 and 78 days after removal DP6 diet. 3) Bile was collected from surgically treated rats fed DP6 diet during 15 days. Polychlorobiphenyls were spotted in fat carcasses, liver, brain, kidney, muscle, feces and urine to determine absorption, distribution in the animal organism and the clearence rates in urine and feces. We found a very hight DP6 absorption and retention. The low excretion and metabolisation of DP6 result in low decrease after removal DP6 diet. PMID:105428

  14. IGM CONSTRAINTS FROM THE SDSS-III/BOSS DR9 Lyα FOREST TRANSMISSION PROBABILITY DISTRIBUTION FUNCTION

    SciTech Connect

    Lee, Khee-Gan; Hennawi, Joseph F.; Spergel, David N.; Weinberg, David H.; Hogg, David W.; Viel, Matteo; Bolton, James S.; Bailey, Stephen; Carithers, William; Schlegel, David J.; Pieri, Matthew M.; Lundgren, Britt; Palanque-Delabrouille, Nathalie; Yèche, Christophe; Schneider, Donald P.

    2015-02-01

    The Lyα forest transmission probability distribution function (PDF) is an established probe of the intergalactic medium (IGM) astrophysics, especially the temperature-density relationship of the IGM. We measure the transmission PDF from 3393 Baryon Oscillations Spectroscopic Survey (BOSS) quasars from Sloan Digital Sky Survey Data Release 9, and compare with mock spectra that include careful modeling of the noise, continuum, and astrophysical uncertainties. The BOSS transmission PDFs, measured at (z) = [2.3, 2.6, 3.0], are compared with PDFs created from mock spectra drawn from a suite of hydrodynamical simulations that sample the IGM temperature-density relationship, γ, and temperature at mean density, T {sub 0}, where T(Δ) = T {sub 0}Δ{sup γ} {sup –} {sup 1}. We find that a significant population of partial Lyman-limit systems (LLSs) with a column-density distribution slope of β{sub pLLS} ∼ – 2 are required to explain the data at the low-transmission end of transmission PDF, while uncertainties in the mean Lyα forest transmission affect the high-transmission end. After modeling the LLSs and marginalizing over mean transmission uncertainties, we find that γ = 1.6 best describes the data over our entire redshift range, although constraints on T {sub 0} are affected by systematic uncertainties. Within our model framework, isothermal or inverted temperature-density relationships (γ ≤ 1) are disfavored at a significance of over 4σ, although this could be somewhat weakened by cosmological and astrophysical uncertainties that we did not model.

  15. Predicting the impacts of climate change on the potential distribution of major native non-food bioenergy plants in China.

    PubMed

    Wang, Wenguo; Tang, Xiaoyu; Zhu, Qili; Pan, Ke; Hu, Qichun; He, Mingxiong; Li, Jiatang

    2014-01-01

    Planting non-food bioenergy crops on marginal lands is an alternative bioenergy development solution in China. Native non-food bioenergy plants are also considered to be a wise choice to reduce the threat of invasive plants. In this study, the impacts of climate change (a consensus of IPCC scenarios A2a for 2080) on the potential distribution of nine non-food bioenergy plants native to China (viz., Pistacia chinensis, Cornus wilsoniana, Xanthoceras sorbifolia, Vernicia fordii, Sapium sebiferum, Miscanthus sinensis, M. floridulus, M. sacchariflorus and Arundo donax) were analyzed using a MaxEnt species distribution model. The suitable habitats of the nine non-food plants were distributed in the regions east of the Mongolian Plateau and the Tibetan Plateau, where the arable land is primarily used for food production. Thus, the large-scale cultivation of those plants for energy production will have to rely on the marginal lands. The variables of "precipitation of the warmest quarter" and "annual mean temperature" were the most important bioclimatic variables for most of the nine plants according to the MaxEnt modeling results. Global warming in coming decades may result in a decrease in the extent of suitable habitat in the tropics but will have little effect on the total distribution area of each plant. The results indicated that it will be possible to grow these plants on marginal lands within these areas in the future. This work should be beneficial for the domestication and cultivation of those bioenergy plants and should facilitate land-use planning for bioenergy crops in China.

  16. Predicting the Impacts of Climate Change on the Potential Distribution of Major Native Non-Food Bioenergy Plants in China

    PubMed Central

    Wang, Wenguo; Tang, Xiaoyu; Zhu, Qili; Pan, Ke; Hu, Qichun; He, Mingxiong; Li, Jiatang

    2014-01-01

    Planting non-food bioenergy crops on marginal lands is an alternative bioenergy development solution in China. Native non-food bioenergy plants are also considered to be a wise choice to reduce the threat of invasive plants. In this study, the impacts of climate change (a consensus of IPCC scenarios A2a for 2080) on the potential distribution of nine non-food bioenergy plants native to China (viz., Pistacia chinensis, Cornus wilsoniana, Xanthoceras sorbifolia, Vernicia fordii, Sapium sebiferum, Miscanthus sinensis, M. floridulus, M. sacchariflorus and Arundo donax) were analyzed using a MaxEnt species distribution model. The suitable habitats of the nine non-food plants were distributed in the regions east of the Mongolian Plateau and the Tibetan Plateau, where the arable land is primarily used for food production. Thus, the large-scale cultivation of those plants for energy production will have to rely on the marginal lands. The variables of “precipitation of the warmest quarter” and “annual mean temperature” were the most important bioclimatic variables for most of the nine plants according to the MaxEnt modeling results. Global warming in coming decades may result in a decrease in the extent of suitable habitat in the tropics but will have little effect on the total distribution area of each plant. The results indicated that it will be possible to grow these plants on marginal lands within these areas in the future. This work should be beneficial for the domestication and cultivation of those bioenergy plants and should facilitate land-use planning for bioenergy crops in China. PMID:25365425

  17. Combining local- and large-scale models to predict the distributions of invasive plant species.

    PubMed

    Jones, Chad C; Acker, Steven A; Halpern, Charles B

    2010-03-01

    Habitat distribution models are increasingly used to predict the potential distributions of invasive species and to inform monitoring. However, these models assume that species are in equilibrium with the environment, which is clearly not true for most invasive species. Although this assumption is frequently acknowledged, solutions have not been adequately addressed. There are several potential methods for improving habitat distribution models. Models that require only presence data may be more effective for invasive species, but this assumption has rarely been tested. In addition, combining modeling types to form "ensemble" models may improve the accuracy of predictions. However, even with these improvements, models developed for recently invaded areas are greatly influenced by the current distributions of species and thus reflect near- rather than long-term potential for invasion. Larger scale models from species' native and invaded ranges may better reflect long-term invasion potential, but they lack finer scale resolution. We compared logistic regression (which uses presence/absence data) and two presence-only methods for modeling the potential distributions of three invasive plant species on the Olympic Peninsula in Washington, USA. We then combined the three methods to create ensemble models. We also developed climate envelope models for the same species based on larger scale distributions and combined models from multiple scales to create an index of near- and long-term invasion risk to inform monitoring in Olympic National Park (ONP). Neither presence-only nor ensemble models were more accurate than logistic regression for any of the species. Larger scale models predicted much greater areas at risk of invasion. Our index of near- and long-term invasion risk indicates that < 4% of ONP is at high near-term risk of invasion while 67-99% of the Park is at moderate or high long-term risk of invasion. We demonstrate how modeling results can be used to guide the

  18. Derivatives of Plant Phenolic Compound Affect the Type III Secretion System of Pseudomonas aeruginosa via a GacS-GacA Two-Component Signal Transduction System

    PubMed Central

    Yamazaki, Akihiro; Li, Jin; Zeng, Quan; Khokhani, Devanshi; Hutchins, William C.; Yost, Angela C.; Biddle, Eulandria; Toone, Eric J.

    2012-01-01

    Antibiotic therapy is the most commonly used strategy to control pathogenic infections; however, it has contributed to the generation of antibiotic-resistant bacteria. To circumvent this emerging problem, we are searching for compounds that target bacterial virulence factors rather than their viability. Pseudomonas aeruginosa, an opportunistic human pathogen, possesses a type III secretion system (T3SS) as one of the major virulence factors by which it secretes and translocates T3 effector proteins into human host cells. The fact that this human pathogen also is able to infect several plant species led us to screen a library of phenolic compounds involved in plant defense signaling and their derivatives for novel T3 inhibitors. Promoter activity screening of exoS, which encodes a T3-secreted toxin, identified two T3 inhibitors and two T3 inducers of P. aeruginosa PAO1. These compounds alter exoS transcription by affecting the expression levels of the regulatory small RNAs RsmY and RsmZ. These two small RNAs are known to control the activity of carbon storage regulator RsmA, which is responsible for the regulation of the key T3SS regulator ExsA. As RsmY and RsmZ are the only targets directly regulated by GacA, our results suggest that these phenolic compounds affect the expression of exoS through the GacSA-RsmYZ-RsmA-ExsA regulatory pathway. PMID:21968370

  19. Protein Export According to Schedule: Architecture, Assembly, and Regulation of Type III Secretion Systems from Plant- and Animal-Pathogenic Bacteria

    PubMed Central

    2012-01-01

    Summary: Flagellar and translocation-associated type III secretion (T3S) systems are present in most Gram-negative plant- and animal-pathogenic bacteria and are often essential for bacterial motility or pathogenicity. The architectures of the complex membrane-spanning secretion apparatuses of both systems are similar, but they are associated with different extracellular appendages, including the flagellar hook and filament or the needle/pilus structures of translocation-associated T3S systems. The needle/pilus is connected to a bacterial translocon that is inserted into the host plasma membrane and mediates the transkingdom transport of bacterial effector proteins into eukaryotic cells. During the last 3 to 5 years, significant progress has been made in the characterization of membrane-associated core components and extracellular structures of T3S systems. Furthermore, transcriptional and posttranscriptional regulators that control T3S gene expression and substrate specificity have been described. Given the architecture of the T3S system, it is assumed that extracellular components of the secretion apparatus are secreted prior to effector proteins, suggesting that there is a hierarchy in T3S. The aim of this review is to summarize our current knowledge of T3S system components and associated control proteins from both plant- and animal-pathogenic bacteria. PMID:22688814

  20. Involvement of a class III peroxidase and the mitochondrial protein TSPO in oxidative burst upon treatment of moss plants with a fungal elicitor.

    PubMed

    Lehtonen, Mikko T; Akita, Motomu; Frank, Wolfgang; Reski, Ralf; Valkonen, Jari P T

    2012-03-01

    Production of apoplastic reactive oxygen species (ROS), or oxidative burst, is among the first responses of plants upon recognition of microorganisms. It requires peroxidase or NADPH oxidase (NOX) activity and factors maintaining cellular redox homeostasis. Here, PpTSPO1 involved in mitochondrial tetrapyrrole transport and abiotic (salt) stress tolerance was tested for its role in biotic stress in Physcomitrella patens, a nonvascular plant (moss). The fungal elicitor chitin caused an immediate oxidative burst in wild-type P. patens but not in the previously described ΔPrx34 mutants lacking the chitin-responsive secreted class III peroxidase (Prx34). Oxidative burst in P. patens was associated with induction of the oxidative stress-related genes AOX, LOX7, and NOX, and also PpTSPO1. The available ΔPpTSPO1 knockout mutants overexpressed AOX and LOX7 constitutively, produced 2.6-fold more ROS than wild-type P. patens, and exhibited increased sensitivity to a fungal necrotrophic pathogen and a saprophyte. These results indicate that Prx34, which is pivotal for antifungal resistance, catalyzes ROS production in P. patens, while PpTSPO1 controls redox homeostasis. The capacity of TSPO to bind harmful free heme and porphyrins and scavenge them through autophagy, as shown in Arabidopsis under abiotic stress, seems important to maintenance of the homeostasis required for efficient pathogen defense. PMID:22112216

  1. Strong and Weak Lensing United III: Measuring the Mass Distribution of the Merging Galaxy Cluster 1E0657-56

    SciTech Connect

    Bradac, Marusa; Clowe, Douglas; Gonzalez, Anthony H.; Marshall, Phil; Forman, William; Jones, Christine; Markevitch, Maxim; Randall, Scott; Schrabback, Tim; Zaritsky, Dennis; /KIPAC, Menlo Park /Bonn, Inst. Astrophys. /Arizona U., Astron. Dept. - Steward Observ. /Florida U. /Harvard-Smithsonian Ctr. Astrophys.

    2006-09-27

    The galaxy cluster 1E0657-56 (z = 0.296) is remarkably well-suited for addressing outstanding issues in both galaxy evolution and fundamental physics. We present a reconstruction of the mass distribution from both strong and weak gravitational lensing data. Multi-color, high-resolution HST ACS images allow detection of many more arc candidates than were previously known, especially around the subcluster. Using the known redshift of one of the multiply imaged systems, we determine the remaining source redshifts using the predictive power of the strong lens model. Combining this information with shape measurements of ''weakly'' lensed sources, we derive a high-resolution, absolutely-calibrated mass map, using no assumptions regarding the physical properties of the underlying cluster potential. This map provides the best available quantification of the total mass of the central part of the cluster. We also confirm the result from Clowe et al. (2004, 2006a) that the total mass does not trace the baryonic mass.

  2. THE INFLUENCE OF SHORT-RANGE INTERACTIONS ON PROTEIN CONFORMATION, III. DIPEPTIDE DISTRIBUTIONS IN PROTEINS OF KNOWN SEQUENCE AND STRUCTURE*

    PubMed Central

    Kotelchuck, D.; Dygert, M.; Scheraga, H. A.

    1969-01-01

    A statistical analysis is made of the distribution into α-helical and non-α-helical regions of the various dipeptide types appearing in a sample of seven proteins of known sequence and structure. By considering as a group all dipeptide types occurring at a given location relative to the reported helix-coil boundaries and examining the percentage of cases in which these appear in non-α-helical regions throughout the protein sample, we find a sharp change in the nature of the observed dipeptide types when the helix-coil boundary is crossed. Furthermore, we find that dipeptide types which occur in the coil region near the C-terminal end of helical segments are non-α-helical in almost 90 per cent of the cases in which they appear throughout the sample. No similar effect is found in the coil region near the N-terminal end of helical segments. These results give evidence for the importance of short-range interactions in determining protein conformation. They are also consistent with predictions based on a model for helix formation given in the second paper of this series.1 PMID:5259754

  3. THE MOST METAL-POOR STARS. III. THE METALLICITY DISTRIBUTION FUNCTION AND CARBON-ENHANCED METAL-POOR FRACTION , ,

    SciTech Connect

    Yong, David; Norris, John E.; Bessell, M. S.; Asplund, M.; Christlieb, N.; Beers, Timothy C.; Barklem, P. S.; Frebel, Anna; Ryan, S. G. E-mail: jen@mso.anu.edu.au E-mail: martin@mso.anu.edu.au E-mail: beers@pa.msu.edu E-mail: afrebel@mit.edu

    2013-01-01

    We examine the metallicity distribution function (MDF) and fraction of carbon-enhanced metal-poor (CEMP) stars in a sample that includes 86 stars with [Fe/H] {<=} -3.0, based on high-resolution, high signal-to-noise spectroscopy, of which some 32 objects lie below [Fe/H] = -3.5. After accounting for the completeness function, the 'corrected' MDF does not exhibit the sudden drop at [Fe/H] = -3.6 that was found in recent samples of dwarfs and giants from the Hamburg/ESO survey. Rather, the MDF decreases smoothly down to [Fe/H] = -4.1. Similar results are obtained from the 'raw' MDF. We find that the fraction of CEMP objects below [Fe/H] = -3.0 is 23% {+-} 6% and 32% {+-} 8% when adopting the Beers and Christlieb and Aoki et al. CEMP definitions, respectively. The former value is in fair agreement with some previous measurements, which adopt the Beers and Christlieb criterion.

  4. Association of Eu(III) and Cm(III) With Halophiles

    NASA Astrophysics Data System (ADS)

    Ozaki, T.; Takenaka, Y.; Ohnuki, T.; Gillow, J. B.; Francis, A. J.

    2003-12-01

    Halophiles live in high ionic strength brine. The mechanisms of metal association with these microorganisms are poorly understood. In this study, we determined the distribution of Eu(III) and Cm(III) on halophiles, Halomonas sp. (WIPP1A) which was isolated from the Waste Isolation Pilot Plant (WIPP) repository in Carlsbad, US., Halomonas elongata (ATCC33173), Halobacterium salinarum (ATCC19700), and Halobacterium halobium (ATCC43214) and examined the coordination environment of Eu(III) adsorbed on the cells by time-resolved laser-induced fluorescence spectroscopy (TRLFS). The cells of Halomonas sp. and H. elongata were grown in media containing 10 - 15 w/v% and 3.5 - 30 w/v% NaCl, respectively. Halobacterium salinarum and H. halobium were grown in media containing 25 w/v% NaCl. The logarithmic distribution coefficient (log Kd) was measured by using the cells at the late exponential phase. After washing the cells with the same concentrations of NaCl, the cells were mixed with 1x10-6 mol dm-3 Eu(III) and 1x10-8 mol dm-3 Cm(III) at pH 5 in the same concentrations of NaCl and log Kd of Eu(III) and Cm(III) was determined. For Halomonas sp. and H. elongata, log Kd was determined as a function of NaCl concentrations. The coordination environment of Eu(III) adsorbed on the cells was estimated by TRLFS. For TRLFS measurements, samples were prepared by adding cells to a solution of 1x10-3 mol dm-3 Eu(III) with the same concentrations of NaCl as the culture media. For Halomonas sp. and H. elongata, log Kd of Cm(III) was apparently larger than that of Eu(III) at all the NaCl concentrations examined. On the other hand, log Kd of Eu(III) and Cm(III) for H. salinarum and H. halobium was almost identical. Our previous study demonstrated that non-halophiles, Chlorella vulgaris, Bacillus subtilis, and Pseudomonas fluorescens show no preferences between these elements. Chemical properties of Eu(III) and Cm(III) are almost identical. Our findings suggest that the difference in log Kd

  5. Distributed Modeling Reveals the Ecohydrological Dynamics Linked with Woody Plant Encroachment in the Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Pierini, N. A.; Vivoni, E. R.; Anderson, C.; Saripalli, S.; Robles-Morua, A.

    2012-12-01

    Woody plant encroachment is an important issue facing semiarid ecosystems in the southwestern United States that is associated with grazing pressures, fire suppression, and the invasion of shrub species into historical grasslands. In this study, we present observational and distributed modeling activities conducted in two small rangeland watersheds of the Santa Rita Experimental Range, Arizona. This Sonoran Desert landscape is representative of the vegetation shift from grasslands to a woody savanna due to the encroachment of velvet mesquite (Prosopis velutina). The paired basins are similar in size and in close proximity, leading to equivalent meteorological and soil conditions. Nevertheless, they vary substantially in mesquite cover, with one basin having undergone a removal treatment several decades ago, while the other watershed represents the regional encroachment process. This distinction presents an excellent case study for analyzing the effects of mesquite encroachment on dryland ecohydrological dynamics. Observational datasets are obtained from a high-resolution environmental sensor network consisting of six rain gauges, twenty-one soil moisture and temperature profiles, five channel runoff flumes and an eddy covariance tower with a complete set of radiation, energy, carbon and water fluxes. In addition, high-resolution digital terrain models and image orthomosaics were obtained from a piloted aircraft with Light Detection and Ranging (LiDAR) measurements and an Unmanned Aerial Vehicle (UAV) with a digital camera. These two remote sensing platforms allowed characterizing the topography, stream network and plant species distributions at a high resolution (<1 m) in both basins. Using the sensor network, we present comparative analyses of watershed rainfall-runoff transformation in the paired basins, illustrating the role that mesquite trees have in runoff generation at the two outlet flumes. We further explore the impact of mesquite trees on the soil

  6. Research and development on a distributed type solar thermal power generation plant

    NASA Astrophysics Data System (ADS)

    Sumida, I.; Tsukamoto, M.; Sakamoto, T.; Taki, T.; Sato, S.

    1983-12-01

    The R&D on a solar thermal power generation system of the plane parabolic type within the framework of the Japanese Sunshine Project is described. This system realizes high concentration of solar energy with a special concentrator module which combines 100 flat plate mirror heliostats of the central tower system with 5 parabolic troughs of the distributed system. A molten salt (KCl-LiCl) type thermal storage unit is used to superheat saturated steam supplied by accumulators to 300-350 C for 90 minutes after 5 hours of heat storage. Specifications and hydrodynamic characteristics for a 1000 kWe pilot plant in Nio, Kagawa, Japan, constructed in 1980 are given.

  7. Root and foliar uptake, translocation, and distribution of [14C] fluoranthene in pea plants (Pisum sativum).

    PubMed

    Zezulka, Stěpán; Klemš, Marek; Kummerová, Marie

    2014-10-01

    Uptake of (14)C-labeled fluoranthene ([(14)C]FLT) via both roots and leaves of Pisum sativum seedlings and distribution of [(14) C] in plants by both acropetal and basipetal transport was evaluated. The highest [(14)C] level was found in the root base (≈270 × 10(4) dpm/g dry wt) and the lowest level in the stem apex (<2 × 10(4) dpm/g dry wt) after just 2 h of root exposure. For foliar uptake, the highest level of [(14)C] was found in the stem and root apex (both ≈2 × 10(4) dpm/g dry wt) (except for treated leaves), while the lowest level was found in the root base (<0.6 × 10(4) dpm/g dry wt).

  8. Proconiini Sharpshooters of Argentina, with Notes on Its Distribution, Host Plants, and Natural Enemies

    PubMed Central

    Paradell, Susana L.; Virla, Eduardo G.; Logarzo, Guillermo A.; Dellapé, Gimena

    2012-01-01

    The American tribe Proconiini (Hemiptera: Cicadellidae: Cicadellinae) is one of the largest groups of xylem-feeding insects and includes the majority of the known vectors of xylem-born phytopathogenic organisms. The significance of the pathogens that this group transmits gives them an important role as pests, mostly for citrus fruit, grapes, and almonds. Knowledge of these Hemiptera in Argentina is insufficient and fragmentary. Thus one of the aims of this paper is to summarize the available information of the Proconiini sharpshooters in Argentina. In addition, 14 species are mentioned for the first time in the country, and new distributional data are given for 18 species. Thirty-four new associations between sharpshooters and host plants are recorded. New records of egg parasitoids are given for Dechacona missionum, Molomea consolida, M. lineiceps, and Tapajosa similis. PMID:23445207

  9. Lidar Investigation of Aerosol Pollution Distribution near a Coal Power Plant

    NASA Technical Reports Server (NTRS)

    Mitsev, TS.; Kolarov, G.

    1992-01-01

    Using aerosol lidars with high spatial and temporal resolution with the possibility of real-time data interpretation can solve a large number of ecological problems related to the aerosol-field distribution and variation and the structure of convective flows. Significantly less expensive specialized lidars are used in studying anthropogenic aerosols in the planetary boundary layer. Here, we present results of lidar measurements of the mass-concentration field around a coal-fired power plant with intensive local aerosol sources. We studied the pollution evolution as a function of the emission dynamics and the presence of retaining layers. The technique used incorporates complex analysis of three types of lidar mapping: horizontal map of the aerosol field, vertical cross-section map, and a series of profiles along a selected path. The lidar-sounding cycle was performed for the time of atmosphere's quasi-stationarity.

  10. Predicting climate change effects on wetland ecosystem services using species distribution modeling and plant functional traits.

    PubMed

    Moor, Helen; Hylander, Kristoffer; Norberg, Jon

    2015-01-01

    Wetlands provide multiple ecosystem services, the sustainable use of which requires knowledge of the underlying ecological mechanisms. Functional traits, particularly the community-weighted mean trait (CWMT), provide a strong link between species communities and ecosystem functioning. We here combine species distribution modeling and plant functional traits to estimate the direction of change of ecosystem processes under climate change. We model changes in CWMT values for traits relevant to three key services, focusing on the regional species pool in the Norrström area (central Sweden) and three main wetland types. Our method predicts proportional shifts toward faster growing, more productive and taller species, which tend to increase CWMT values of specific leaf area and canopy height, whereas changes in root depth vary. The predicted changes in CWMT values suggest a potential increase in flood attenuation services, a potential increase in short (but not long)-term nutrient retention, and ambiguous outcomes for carbon sequestration.

  11. Relationships of salt-marsh plant distributions to tidal levels in Connecticut, USA

    SciTech Connect

    Lefor, M.W.; Kennard, W.C.; Civco, D.L.

    1987-01-01

    A three-year study of Connecticut, USA, salt-marsh vegetation was undertaken to determine the relationship of its distribution on the marsh surface to tidal levels, particularly mean high water (MHW) as measured on each of three sites representing different tidal amplitudes. Elevations and species present were measured on 1-m/sup 2/ grids in 10 x 70-m belt transects at each site. After the data were subjected to discriminant analysis and other standard statistical procedures, the results showed that 98.4% of all observations of Spartina alterniflora Loisel. occurred at or below MHW. The data can aid in salt-marsh restoration by offering a reliable indicator of what species should be planted when restored elevations and on-site MHW are known.

  12. Effects of phylogeny, leaf traits, and the altitudinal distribution of host plants on herbivore assemblages on congeneric Acer species.

    PubMed

    Nakadai, Ryosuke; Murakami, Masashi; Hirao, Toshihide

    2014-08-01

    Historical, niche-based, and stochastic processes have been proposed as the mechanisms that drive community assembly. In plant-herbivore systems, these processes can correspond to phylogeny, leaf traits, and the distribution of host plants, respectively. Although patterns of herbivore assemblages among plant species have been repeatedly examined, the effects of these factors among co-occurring congeneric host plant species have rarely been studied. Our aim was to reveal the process of community assembly for herbivores by investigating the effects of phylogeny, leaf traits, and the altitudinal distribution of closely related host plants of the genus Acer. We sampled leaf functional traits for 30 Acer species in Japan. Using a newly constructed phylogeny, we determined that three of the six measured leaf traits (leaf thickness, C/N ratio, and condensed tannin content) showed a phylogenetic signal. In a field study, we sampled herbivore communities on 14 Acer species within an elevation gradient and examined relationships between herbivore assemblages and host plants. We found that herbivore assemblages were significantly correlated with phylogeny, leaf traits, phylogenetic signals, and the altitudinal distribution of host plants. Our results indicate that the interaction between historical and current ecological processes shapes herbivore community assemblages.

  13. Arsenic distribution in soils and rye plants of a cropland located in an abandoned mining area.

    PubMed

    Álvarez-Ayuso, Esther; Abad-Valle, Patricia; Murciego, Ascensión; Villar-Alonso, Pedro

    2016-01-15

    A mining impacted cropland was studied in order to assess its As pollution level and the derived environmental and health risks. Profile soil samples (0-50 cm) and rye plant samples were collected at different distances (0-150 m) from the near mine dump and analyzed for their As content and distribution. These cropland soils were sandy, acidic and poor in organic matter and Fe/Al oxides. The soil total As concentrations (38-177 mg kg(-1)) and, especially, the soil soluble As concentrations (0.48-4.1 mg kg(-1)) importantly exceeded their safe limits for agricultural use of soils. Moreover, the soil As contents more prone to be mobilized could rise up to 25-69% of total As levels as determined using (NH4)2SO4, NH4H2PO4 and (NH4)2C2O4·H2O as sequential extractants. Arsenic in rye plants was primarily distributed in roots (3.4-18.8 mg kg(-1)), with restricted translocation to shoots (TF=0.05-0.26) and grains (TF=<0.02-0.14). The mechanism for this excluder behavior should be likely related to arsenate reduction to arsenite in roots, followed by its complexation with thiols, as suggested by the high arsenite level in rye roots (up to 95% of the total As content) and the negative correlation between thiol concentrations in rye roots and As concentrations in rye shoots (|R|=0.770; p<0.01). Accordingly, in spite of the high mobile and mobilizable As contents in soils, As concentrations in rye above-ground tissues comply with the European regulation on undesirable substances in animal feed. Likewise, rye grain As concentrations were below its maximum tolerable concentration in cereals established by international legislation. PMID:26519583

  14. Arsenic distribution in soils and rye plants of a cropland located in an abandoned mining area.

    PubMed

    Álvarez-Ayuso, Esther; Abad-Valle, Patricia; Murciego, Ascensión; Villar-Alonso, Pedro

    2016-01-15

    A mining impacted cropland was studied in order to assess its As pollution level and the derived environmental and health risks. Profile soil samples (0-50 cm) and rye plant samples were collected at different distances (0-150 m) from the near mine dump and analyzed for their As content and distribution. These cropland soils were sandy, acidic and poor in organic matter and Fe/Al oxides. The soil total As concentrations (38-177 mg kg(-1)) and, especially, the soil soluble As concentrations (0.48-4.1 mg kg(-1)) importantly exceeded their safe limits for agricultural use of soils. Moreover, the soil As contents more prone to be mobilized could rise up to 25-69% of total As levels as determined using (NH4)2SO4, NH4H2PO4 and (NH4)2C2O4·H2O as sequential extractants. Arsenic in rye plants was primarily distributed in roots (3.4-18.8 mg kg(-1)), with restricted translocation to shoots (TF=0.05-0.26) and grains (TF=<0.02-0.14). The mechanism for this excluder behavior should be likely related to arsenate reduction to arsenite in roots, followed by its complexation with thiols, as suggested by the high arsenite level in rye roots (up to 95% of the total As content) and the negative correlation between thiol concentrations in rye roots and As concentrations in rye shoots (|R|=0.770; p<0.01). Accordingly, in spite of the high mobile and mobilizable As contents in soils, As concentrations in rye above-ground tissues comply with the European regulation on undesirable substances in animal feed. Likewise, rye grain As concentrations were below its maximum tolerable concentration in cereals established by international legislation.

  15. Central heating plant modernization study for defense distribution Region East. Final report

    SciTech Connect

    Savoie, M.J.; Durbin, T.E.; McCammon, T.; Carroll, R.

    1996-08-01

    Due to the age of its central heating plant (CHP) equipment and changes in energy industry environmental regulations, the Defense Distribution Region East (DDRE), New Cumberland, PA, began investigating modernization opportunities for its CHP. The U.S. Army Construction Engineering Research Laboratories (USACERL) was tasked with performing a central heating plant modernization study to determine viable options to provide energy for the coming years. Energy use patterns and the condition of existing equipment were determined, and five major potential energy supply alternatives were identified and evaluated on the basis of energy consumption and economics, including initial capital costs, annual fuel consumption, and annual Operations and Maintenance (OM) costs. For economy, it was recommended that boiler replacement be delayed until the year 2009, and that natural gas be used as fuel both before and after replacement, provided that funding for a natural gas pipeline can be obtained. If funding to replace the boilers does become available, the small difference in Life Cycle Cost should not delay DDRE from an immediate equipment upgrade.

  16. Distribution of heavy metals in plants and fish of the Yamuna river (India).

    PubMed

    Ajmal, M; Khan, M A; Nomani, A A

    1985-12-01

    The distribution of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in the plants and fish of Yamuna river from Delhi to Allahabad, a distance of about 840 km, at five sampling stations was determined in the year 1981. The results have shown wide variations in the heavy metal levels from one sampling station to the other. The concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn in the plants (Eicchornia crassipes) were found to be 0.02-0.12, 2.7-21.3, 4.6-64.8, 9.8-114.0, 193.0-1835.0, 380.0-1443.0, 4.4-83.0, 4.8-30.2, and 22.1-356.5 μg g(-1) respectively whereas in the fish (Heteropnuestes fossilis) were found to be ND-0.40, 2.3-13.7, 3.7-26.9, 8.33-58.1, 278.3-1108.0, 81.3-213.8, 2.8-32.7, 1.4-12.8 and 101.8-364.8 μgg(-1) respectively on dry weight basis. PMID:24258102

  17. Distribution of pollutants from a new paper plant in southern Lake Champlain, Vermont and New York

    USGS Publications Warehouse

    Mason, D.L.; Folger, D.W.; Haupt, R.S.; McGirr, R.R.; Hoyt, W.H.

    1977-01-01

    From November of 1973 to May of 1974, 15 arrays of sediment traps were placed along 33 km of southern Lake Champlain to sample the distribution of effluent from a large paper plant located on the western shore which had commenced operation in 1971. In the arrays located near the effluent diffuser pipeline as much as 2.3 cm of sediment accumulated, whereas elsewhere in the lake less than 1 cm accumulated. In the area of accelerated accumulation, sediments contained high concentrations of several components used in or derived from paper manufacturing. Values for kaolinite, expressed as the ratio of kaolinite to chlorite, for example, were as high as 1.4, anatase (TiO2) concentrations were as high as 0.8%, organic carbon 8.7%, and phosphorus 254 ??g/g; all were more abundant than in sediments collected in traps to the south or north. In surficial bottom sediments collected near each array organic carbon and phosphorus were also higher (4.2% and 127 ??g/g respectively) near the diffuser than elsewhere. Thus, the new plant after three years of production measurably affected the composition of suspended sediment and surficial bottom sediment despite the construction and use of extensive facilities to reduce the flow of pollutants to the lake. ?? 1977 Springer-Verlag New York Inc.

  18. Spatial distribution of understory plants along gradients of water and light availability

    SciTech Connect

    Holmgren, M.; Huston, M.A.; Quiles, J.; Warner, S. )

    1994-06-01

    We measured the percent cover, stem densities, and heights of understory plant species in 72 3 [times] 3m plots on a southeast-facing slope of mature mixed oak forest. The 80 [times] 240 m site is intensively instrumented for monitoring soil water content using the Time Domain Reflectometry method as part of the Throughfall Displacement Experiment on Walker Branch Watershed. We estimated canopy openness in each of the plots using hemispherical photographs. The goal of the research was to determined if the spatial distribution of understory community structure was consistent with hypothesized limitations imposed by water availability on plant responses to light. We measured the natural patterns of size, abundance, and survival of seedlings of fourteen tree species under a range of light and soil water availability. Seedling densities ranged from 4 individuals per meter square under dry, low light conditions, to 27 per meter square under the high light, high moisture conditions. Red maple comprised about two thirds of the total number of seedlings. Several distinct types of responses can be identified from three-dimensional graphs of size, abundance, or survival in relation to light and water.

  19. Distribution of heavy metals in plants and fish of the Yamuna river (India).

    PubMed

    Ajmal, M; Khan, M A; Nomani, A A

    1985-12-01

    The distribution of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in the plants and fish of Yamuna river from Delhi to Allahabad, a distance of about 840 km, at five sampling stations was determined in the year 1981. The results have shown wide variations in the heavy metal levels from one sampling station to the other. The concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn in the plants (Eicchornia crassipes) were found to be 0.02-0.12, 2.7-21.3, 4.6-64.8, 9.8-114.0, 193.0-1835.0, 380.0-1443.0, 4.4-83.0, 4.8-30.2, and 22.1-356.5 μg g(-1) respectively whereas in the fish (Heteropnuestes fossilis) were found to be ND-0.40, 2.3-13.7, 3.7-26.9, 8.33-58.1, 278.3-1108.0, 81.3-213.8, 2.8-32.7, 1.4-12.8 and 101.8-364.8 μgg(-1) respectively on dry weight basis.

  20. The Xanthomonas campestris Type III Effector XopJ Targets the Host Cell Proteasome to Suppress Salicylic-Acid Mediated Plant Defence

    PubMed Central

    Börnke, Frederik

    2013-01-01

    The phytopathogenic bacterium Xanthomonas campestris pv. vesicatoria (Xcv) requires type III effector proteins (T3Es) for virulence. After translocation into the host cell, T3Es are thought to interact with components of host immunity to suppress defence responses. XopJ is a T3E protein from Xcv that interferes with plant immune responses; however, its host cellular target is unknown. Here we show that XopJ interacts with the proteasomal subunit RPT6 in yeast and in planta to inhibit proteasome activity. A C235A mutation within the catalytic triad of XopJ as well as a G2A exchange within the N-terminal myristoylation motif abolishes the ability of XopJ to inhibit the proteasome. Xcv ΔxopJ mutants are impaired in growth and display accelerated symptom development including tissue necrosis on susceptible pepper leaves. Application of the proteasome inhibitor MG132 restored the ability of the Xcv ΔxopJ to attenuate the development of leaf necrosis. The XopJ dependent delay of tissue degeneration correlates with reduced levels of salicylic acid (SA) and changes in defence- and senescence-associated gene expression. Necrosis upon infection with Xcv ΔxopJ was greatly reduced in pepper plants with reduced expression of NPR1, a central regulator of SA responses, demonstrating the involvement of SA-signalling in the development of XopJ dependent phenotypes. Our results suggest that XopJ-mediated inhibition of the proteasome interferes with SA-dependent defence response to attenuate onset of necrosis and to alter host transcription. A central role of the proteasome in plant defence is discussed. PMID:23785289

  1. Measurements of LET-distribution, dose equivalent and quality factor with the RRMD-III on the Space Shuttle Missions STS-84, -89 and -91.

    PubMed

    Doke, T; Hayashi, T; Kikuchi, J; Sakaguchi, T; Terasawa, K; Yoshihira, E; Nagaoka, S; Nakano, T; Takahashi, S

    2001-06-01

    Dosimetric measurements on the Space Shuttle Missions STS-84, -89 and -91 have been made by the real-time radiation monitoring device III (RRMD-III). Simultaneously, another dosimetry measurement was made by the Dosimetry Telescope (DOSTEL) on STS-84 and by the tissue-equivalent proportional counter (TEPC) on STS-91. First, the RRMD-III instrument is described in detail and its results summarized. Then, the results of DOSTEL and TEPC are compared with those of the RRMD-III. Also, the absorbed doses obtained by TLD (Mg2SiO4) and by RRMD-III on board STS-84 and -91 are compared.

  2. Accumulation and distribution characteristics of zinc and cadmium in the hyperaccumulator plant Sedum plumbizincicola.

    PubMed

    Cao, Dong; Zhang, Hongzheng; Wang, Yaodong; Zheng, Leina

    2014-08-01

    Accumulation and distribution of Zn and Cd in the hyperaccumulator plant Sedum plumbizincicola were investigated in a hydroponic experiment. Mean Cd and Zn concentrations in shoots (7,010 and 18,400 mg kg(-1)) were about sevenfold and fivefold higher than those in roots (840 and 3,000 mg kg(-1)) after exposure to 100 μM CdSO4 and 600 μM ZnSO4, respectively. Cd and Zn concentrations in young leaves (4,330 and 9,820 mg kg(-1)) were about sixfold and twofold higher than those in mature leaves (636 and 2,620 mg kg(-1)), respectively. MicroPIXE analysis showed that Zn was predominantly localized in epidermal cells in both young and mature leaves, but large amounts of Zn occurred in mesophyll cells in young leaves. Leaf tissue fractionation showed that soluble and cell wall fractions were different at the two stages of leaf growth. Young and mature leaves of S. plumbizincicola also showed different accumulation and distribution characteristics for Zn and Cd. PMID:24789526

  3. Evaluation of population density and distribution criteria in nuclear power plant siting

    SciTech Connect

    Young, M.

    1994-06-01

    The NRC has proposed revisions to 10 CFR 100 which include the codification of nuclear reactor site population density limits to 500 people per square mile, at the siting stage, averaged over any radial distance out to 30 miles, and 1,000 people per square mile within the 40-year lifetime of a nuclear plant. This study examined whether there are less restrictive alternative population density and/or distribution criteria which would provide equivalent or better protection to human health in the unlikely event of a nuclear accident. This study did not attempt to directly address the issue of actual population density limits because there are no US risk standards established for the evaluation of population density limits. Calculations were performed using source terms for both a current generation light water reactor (LWR) and an advanced light water reactor (ALWR) design. The results of this study suggest that measures which address the distribution of the population density, including emergency response conditions, could result in lower average individual risks to the public than the proposed guidelines that require controlling average population density. Studies also indicate that an exclusion zone size, determined by emergency response conditions and reactor design (power level and safety features), would better serve to protect public health than a rigid standard applied to all sites.

  4. Problems in Assessment of Wind Energy Potential and Acoustic Noise Distribution when Designing Wind Power Plants

    NASA Astrophysics Data System (ADS)

    Bezrukovs, Valerijs; Bezrukovs, Vladislavs; Levins, Nikolajs

    2011-01-01

    Interest in the use of renewable energy in Latvia is increasing every year. Government support and availability of large unpopulated areas on the coast makes the use of these lands for the placement of large wind power plants (WPP) attractive. The key factors that determine the choice of the location of WPP are reliable information about distribution of the resource of wind energy in this area and the influence of wind turbines on the environment. The paper presents the results of years-long observations on the density fluctuations of wind energy at heights of 10 to 60 m in the area in the Baltic Sea coast in Ventspils and Ainaži. The velocity observations since 2007 have been gathered by measurements complex of the LOGGER 9200 Symphonie type. The results are presented in the form of tables, bar charts and graphs. Extrapolation results of wind velocity and density mean values on heights up to 150 m for the two areas with different terrain types were shown. The distribution of acoustic noise in the vicinity of the WPP was studied and an assessment of its impact on the environment in accordance with the Latvian government requirements was conducted.

  5. Global hotspots in the present-day distribution of ancient animal and plant lineages

    PubMed Central

    Procheş, Şerban; Ramdhani, Syd; Perera, Sandun J.; Ali, Jason R.; Gairola, Sanjay

    2015-01-01

    The current distribution of biotic lineages that emerged in the deep time has both theoretical and practical implications, in particular for understanding the processes that have forged present-day biodiversity and informing local and regional-scale conservation efforts. To date however, there has been no examination of such patterns globally across taxa and geological time. Here we map the diversity of selected extant seed plant and tetrapod vertebrate lineages that were already in existence either in the latest Triassic or latest Cretaceous. For Triassic-age linages, we find concentrations in several regions – both tropical and temperate – parts of North America, Europe, East and South-east Asia, northern South America, and New Zealand. With Cretaceous-age lineages, high values are relatively uniformly distributed across the tropics, with peak the values along the Andes, in South-east Asia and Queensland, but also in the temperate Cape Mountains. These patterns result from a combination of factors, including land area, geographic isolation, climate stability and mass extinction survival ability. While the need to protect many of these lineages has been long recognised, a spatially-explicit approach is critical for understanding and maintaining the factors responsible for their persistence, and this will need to be taken forward across finer scales. PMID:26498226

  6. Aromatic amine contents, component distributions and risk assessment in sludge from 10 textile-dyeing plants.

    PubMed

    Ning, Xun-An; Liang, Jie-Ying; Li, Rui-Jing; Hong, Zhen; Wang, Yu-Jie; Chang, Ken-Lin; Zhang, Ya-Ping; Yang, Zuo-Yi

    2015-09-01

    Aromatic amines (AAs), which are components of synthetic dyes, are recalcitrant to the wastewater treatment process and can accumulate in sludge produced by textile-dyeing, which may pose a threat to the environment. A comprehensive investigation of 10 textile-dyeing plants was undertaken in Guangdong Province in China. The contents and component distributions of AAs were evaluated in this study, and a risk assessment was performed. The total concentrations of 14 AAs (Σ14 AAs) varied from 11 μg g(-1)dw to 82.5 μg g(-1)dw, with a mean value of 25 μg g(-1)dw. The component distributions of AAs were characterized by monocyclic anilines, of which 2-methoxy-5-methylaniline and 5-nitro-o-toluidine were the most dominant components. The risk quotient (RQ) value was used to numerically evaluate the ecological risk of 14 AAs in the environment. The result showed that the 14 AAs contents in textile-dyeing sludge may pose a high risk to the soil ecosystem after being discarded on soil or in a landfill.

  7. Pepper Heat Shock Protein 70a Interacts with the Type III Effector AvrBsT and Triggers Plant Cell Death and Immunity1[OPEN

    PubMed Central

    Kim, Nak Hyun; Hwang, Byung Kook

    2015-01-01

    Heat shock proteins (HSPs) function as molecular chaperones and are essential for the maintenance and/or restoration of protein homeostasis. The genus Xanthomonas type III effector protein AvrBsT induces hypersensitive cell death in pepper (Capsicum annuum). Here, we report the identification of the pepper CaHSP70a as an AvrBsT-interacting protein. Bimolecular fluorescence complementation and coimmunoprecipitation assays confirm the specific interaction between CaHSP70a and AvrBsT in planta. The CaHSP70a peptide-binding domain is essential for its interaction with AvrBsT. Heat stress (37°C) and Xanthomonas campestris pv vesicatoria (Xcv) infection distinctly induce CaHSP70a in pepper leaves. Cytoplasmic CaHSP70a proteins significantly accumulate in pepper leaves to induce the hypersensitive cell death response by Xcv (avrBsT) infection. Transient CaHSP70a overexpression induces hypersensitive cell death under heat stress, which is accompanied by strong induction of defense- and cell death-related genes. The CaHSP70a peptide-binding domain and ATPase-binding domain are required to trigger cell death under heat stress. Transient coexpression of CaHSP70a and avrBsT leads to cytoplasmic localization of the CaHSP70a-AvrBsT complex and significantly enhances avrBsT-triggered cell death in Nicotiana benthamiana. CaHSP70a silencing in pepper enhances Xcv growth but disrupts the reactive oxygen species burst and cell death response during Xcv infection. Expression of some defense marker genes is significantly reduced in CaHSP70a-silenced leaves, with lower levels of the defense hormones salicylic acid and jasmonic acid. Together, these results suggest that CaHSP70a interacts with the type III effector AvrBsT and is required for cell death and immunity in plants. PMID:25491184

  8. OsPIN5b modulates rice (Oryza sativa) plant architecture and yield by changing auxin homeostasis, transport and distribution.

    PubMed

    Lu, Guangwen; Coneva, Viktoriya; Casaretto, José A; Ying, Shan; Mahmood, Kashif; Liu, Fang; Nambara, Eiji; Bi, Yong-Mei; Rothstein, Steven J

    2015-09-01

    Plant architecture attributes such as tillering, plant height and panicle size are important agronomic traits that determine rice (Oryza sativa) productivity. Here, we report that altered auxin content, transport and distribution affect these traits, and hence rice yield. Overexpression of the auxin efflux carrier-like gene OsPIN5b causes pleiotropic effects, mainly reducing plant height, leaf and tiller number, shoot and root biomass, seed-setting rate, panicle length and yield parameters. Conversely, reduced expression of OsPIN5b results in higher tiller number, more vigorous root system, longer panicles and increased yield. We show that OsPIN5b is an endoplasmic reticulum (ER) -localized protein that participates in auxin homeostasis, transport and distribution in vivo. This work describes an example of an auxin-related gene where modulating its expression can simultaneously improve plant architecture and yield potential in rice, and reveals an important effect of hormonal signaling on these traits.

  9. Citizen science contributes to our knowledge of invasive plant species distributions

    USGS Publications Warehouse

    Crall, Alycia W.; Jarnevich, Catherine S.; Young, Nicholas E.; Panke, Brendon; Renz, Mark; Stohlgren, Thomas

    2015-01-01

    Citizen science is commonly cited as an effective approach to expand the scale of invasive species data collection and monitoring. However, researchers often hesitate to use these data due to concerns over data quality. In light of recent research on the quality of data collected by volunteers, we aimed to demonstrate the extent to which citizen science data can increase sampling coverage, fill gaps in species distributions, and improve habitat suitability models compared to professionally generated data sets used in isolation. We combined data sets from professionals and volunteers for five invasive plant species (Alliaria petiolata, Berberis thunbergii, Cirsium palustre, Pastinaca sativa, Polygonum cuspidatum) in portions of Wisconsin. Volunteers sampled counties not sampled by professionals for three of the five species. Volunteers also added presence locations within counties not included in professional data sets, especially in southern portions of the state where professional monitoring activities had been minimal. Volunteers made a significant contribution to the known distribution, environmental gradients sampled, and the habitat suitability of P. cuspidatum. Models generated with professional data sets for the other four species performed reasonably well according to AUC values (>0.76). The addition of volunteer data did not greatly change model performance (AUC > 0.79) but did change the suitability surface generated by the models, making them more realistic. Our findings underscore the need to merge data from multiple sources to improve knowledge of current species distributions, and to predict their movement under present and future environmental conditions. The efficiency and success of these approaches require that monitoring efforts involve multiple stakeholders in continuous collaboration via established monitoring networks.

  10. Predicting plant invasions under climate change: are species distribution models validated by field trials?

    PubMed

    Sheppard, Christine S; Burns, Bruce R; Stanley, Margaret C

    2014-09-01

    Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk. Three recently naturalized alien plants in New Zealand were used as study species (Archontophoenix cunninghamiana, Psidium guajava and Schefflera actinophylla): they originate from warm native ranges, are woody bird-dispersed species and of concern as potential weeds. Seedlings were grown in six sites across the country, differing both in climate and suitability (as predicted by the species distribution models). Seedling growth and survival were recorded over two summers and one or two winter seasons, and temperature and precipitation were monitored hourly at each site. Additionally, alien seedling performances were compared to those of closely related native species (Rhopalostylis sapida, Lophomyrtus bullata and Schefflera digitata). Furthermore, half of the seedlings were sprayed with pesticide, to investigate whether enemy release may influence performance. The results showed large differences in growth and survival of the alien species among the six sites. In the more suitable sites, performance was frequently higher compared to the native species. Leaf damage from invertebrate herbivory was low for both alien and native seedlings, with little evidence that the alien species should have an advantage over the native species because of enemy release. Correlations between performance in the field and predicted suitability of species distribution models were generally high. The projected increase in minimum temperature and reduced

  11. Predicting plant invasions under climate change: are species distribution models validated by field trials?

    PubMed

    Sheppard, Christine S; Burns, Bruce R; Stanley, Margaret C

    2014-09-01

    Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk. Three recently naturalized alien plants in New Zealand were used as study species (Archontophoenix cunninghamiana, Psidium guajava and Schefflera actinophylla): they originate from warm native ranges, are woody bird-dispersed species and of concern as potential weeds. Seedlings were grown in six sites across the country, differing both in climate and suitability (as predicted by the species distribution models). Seedling growth and survival were recorded over two summers and one or two winter seasons, and temperature and precipitation were monitored hourly at each site. Additionally, alien seedling performances were compared to those of closely related native species (Rhopalostylis sapida, Lophomyrtus bullata and Schefflera digitata). Furthermore, half of the seedlings were sprayed with pesticide, to investigate whether enemy release may influence performance. The results showed large differences in growth and survival of the alien species among the six sites. In the more suitable sites, performance was frequently higher compared to the native species. Leaf damage from invertebrate herbivory was low for both alien and native seedlings, with little evidence that the alien species should have an advantage over the native species because of enemy release. Correlations between performance in the field and predicted suitability of species distribution models were generally high. The projected increase in minimum temperature and reduced

  12. Time series changes in radiocaesium distribution in tea plants (Camellia sinensis (L.)) after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Hirono, Yuhei; Nonaka, Kunihiko

    2016-02-01

    Radiocaesium ((134)Cs and (137)Cs) release following the accident at the Fukushima Dai-ichi Nuclear Power Plant, belonging to the Tokyo Electric Power Company caused severe contamination of new tea plant (Camellia sinensis (L.)) shoots by radiocaesium in many prefectures in eastern Japan. Because tea plants are perennial crops, there is the fear that the contamination might last for a long time. The objectives of this study were to reveal time series changes in the distribution of radiocaesium in tea plants after radioactive fallout and to evaluate the effect of pruning on reduction of radiocaesium concentrations in new shoots growing next year. The experimental tea field was located in Shizuoka, Japan, approximately 400 km away from the Fukushima Dai-ichi Nuclear Power Plant in a southwest direction. Time series changes in radiocaesium concentrations in unrefined tea, a tea product primarily produced for making Japanese green tea, from May 2011 to June 2013 and distribution of radiocaesium in tea plants from May 2011 to May 2012 were monitored. The radiocaesium concentrations in unrefined tea exponentially decreased; the effective half-lives for (134)Cs and (137)Cs were 0.30 and 0.36 y during the first 2 y after the accident, respectively. With time, the highest concentrations of (137)Cs moved from the upper to the lower parts of plants. Medium pruning 2-3 months after the accident reduced the concentration of (137)Cs in new shoots harvested in the first crop season of the following year by 56% compared with unpruned tea plants; thus, pruning is an effective measure for reducing radiocaesium concentration in tea. PMID:26695880

  13. Time series changes in radiocaesium distribution in tea plants (Camellia sinensis (L.)) after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Hirono, Yuhei; Nonaka, Kunihiko

    2016-02-01

    Radiocaesium ((134)Cs and (137)Cs) release following the accident at the Fukushima Dai-ichi Nuclear Power Plant, belonging to the Tokyo Electric Power Company caused severe contamination of new tea plant (Camellia sinensis (L.)) shoots by radiocaesium in many prefectures in eastern Japan. Because tea plants are perennial crops, there is the fear that the contamination might last for a long time. The objectives of this study were to reveal time series changes in the distribution of radiocaesium in tea plants after radioactive fallout and to evaluate the effect of pruning on reduction of radiocaesium concentrations in new shoots growing next year. The experimental tea field was located in Shizuoka, Japan, approximately 400 km away from the Fukushima Dai-ichi Nuclear Power Plant in a southwest direction. Time series changes in radiocaesium concentrations in unrefined tea, a tea product primarily produced for making Japanese green tea, from May 2011 to June 2013 and distribution of radiocaesium in tea plants from May 2011 to May 2012 were monitored. The radiocaesium concentrations in unrefined tea exponentially decreased; the effective half-lives for (134)Cs and (137)Cs were 0.30 and 0.36 y during the first 2 y after the accident, respectively. With time, the highest concentrations of (137)Cs moved from the upper to the lower parts of plants. Medium pruning 2-3 months after the accident reduced the concentration of (137)Cs in new shoots harvested in the first crop season of the following year by 56% compared with unpruned tea plants; thus, pruning is an effective measure for reducing radiocaesium concentration in tea.

  14. How does biomass distribution change with size and differ among species? An analysis for 1200 plant species from five continents.

    PubMed

    Poorter, Hendrik; Jagodzinski, Andrzej M; Ruiz-Peinado, Ricardo; Kuyah, Shem; Luo, Yunjian; Oleksyn, Jacek; Usoltsev, Vladimir A; Buckley, Thomas N; Reich, Peter B; Sack, Lawren

    2015-11-01

    We compiled a global database for leaf, stem and root biomass representing c. 11 000 records for c. 1200 herbaceous and woody species grown under either controlled or field conditions. We used this data set to analyse allometric relationships and fractional biomass distribution to leaves, stems and roots. We tested whether allometric scaling exponents are generally constant across plant sizes as predicted by metabolic scaling theory, or whether instead they change dynamically with plant size. We also quantified interspecific variation in biomass distribution among plant families and functional groups. Across all species combined, leaf vs stem and leaf vs root scaling exponents decreased from c. 1.00 for small plants to c. 0.60 for the largest trees considered. Evergreens had substantially higher leaf mass fractions (LMFs) than deciduous species, whereas graminoids maintained higher root mass fractions (RMFs) than eudicotyledonous herbs. These patterns do not support the hypothesis of fixed allometric exponents. Rather, continuous shifts in allometric exponents with plant size during ontogeny and evolution are the norm. Across seed plants, variation in biomass distribution among species is related more to function than phylogeny. We propose that the higher LMF of evergreens at least partly compensates for their relatively low leaf area : leaf mass ratio.

  15. Flowers as islands: spatial distribution of nectar-inhabiting microfungi among plants of Mimulus aurantiacus, a hummingbird-pollinated shrub

    PubMed Central

    Belisle, Melinda; Peay, Kabir G.; Fukami, Tadashi

    2014-01-01

    Microfungi inhabiting floral nectar offer unique opportunities for the study of microbial distribution and the role that dispersal limitation may play in generating distribution patterns. Flowers are well-replicated habitat islands, among which the microbes disperse via pollinators. This metapopulation system allows for investigation of microbial distribution at multiple spatial scales. We examined the distribution of the yeast, Metschnikowia reukaufii, and other fungal species found in the floral nectar of the sticky monkey flower, Mimulus aurantiacus, a hummingbird-pollinated shrub, at a California site. We found that the frequency of nectar-inhabiting microfungi on a given host plant was not significantly correlated with light availability, nectar volume or the percent cover of M. aurantiacus around the plant, but was significantly correlated with the location of the host plant and loosely correlated with the density of flowers on the plant. These results suggest that dispersal limitation caused by spatially non-random foraging by pollinators may be a primary factor driving the observed distribution pattern. PMID:22080257

  16. Invasive alien plants in Croatia as a threat to biodiversity of South-Eastern Europe: distributional patterns and range size.

    PubMed

    Nikolić, Toni; Mitić, Božena; Milašinović, Boris; Jelaska, Sven D

    2013-02-01

    During the analysis of alien and invasive flora of Europe, as a threat to biodiversity, data for Croatia were missing. The aim of our research was to analyse distributional patterns and range size of all invasive alien plants (64) for the state area (57,000 km(2)). They were detected on 49% of the state territory, averaging five taxa per 35 km(2). The greatest number of invasive plants (>30 per grid cell) was recorded in the major urban centres, increasing in the south-east direction and reflecting positive correlation with temperature and negative with altitude. The most endangered areas are in the Mediterranean region, especially on islands. The number of invasive plants increased with habitat diversity and almost 75% of all sites with invasive plants are located within a few habitats with direct anthropogenic influence. The results should provide a reliable regional and global basis for strategic planning regarding invasive alien plants management.

  17. Occurrence and distribution of special status plant species on the Naval Petroleum Reserves in California

    SciTech Connect

    Anderson, D.C.; Cypher, B.L.; Holmstead, G.L.; Hammer, K.L.; Frost, N.

    1994-10-01

    Several special status plant species occur or potentially occur at the Naval Petroleum Reserves in California (NPRC). Special status species are defined as those species that are either federally listed as endangered or threatened, or candidate taxa. Candidate species are classified as Category 1 or Category 2. Category 1 taxa are those species for which there is sufficient evidence to support listing, while Category 2 taxa are those species for which listing may possibly be appropriate, but for which sufficient data are lacking to warrant immediate listing. Determining the presence and distribution of these species on NPRC is necessary so that appropriate conservation or protection measures can be implemented. In the spring of 1988, a survey of Naval Petroleum Reserve No. 1 (NPR-1) was conducted to determine the occurrence of Hoover`s wooly-star (Eriastrum hooveri), Kern Mallow (Eremalche kemensis), San Joaquin wooly-threads (Lembertia congdonii), and California jewelflower (Caulanthus califonicus), all listed by the US Fish and Wildlife Service (FWS) as Category 2 species at that time. Of the four species, only Hoover`s wooly-star was found. It was concluded that Kern mallow and San Joaquin wooly-threads could potentially be found on NPR-1, but habitat for California jewelflower did not occur on NPR-1 and its occurrence was unlikely. As part of an ongoing effort to document the presence or absence of sensitive plant species on NPRC, surveys for species other than Hoover`s wooly-star were conducted in the spring of 1993. Abundant spring rains in 1993 created favorable growing conditions for annual forbs. Surveys in 1993 focused on potential habitat of several endangered and candidate species. The results of those surveys are presented in this report.

  18. Molecular Analysis of Terminalia spp. Distributed in Thailand and Authentication of Crude Drugs from Terminalia Plants.

    PubMed

    Intharuksa, Aekkhaluck; Ando, Hirokazu; Miyake, Katsunori; Sirisa-Ard, Panee; Mikage, Masayuki; Sasaki, Yohei

    2016-01-01

    Terminalia, a large genus of Combretaceae, is distributed in Tropical Asia, Africa, and America. Some Terminalia plants are used in folk medicine because they possess powerful medicinal properties. Dried fruits of Terminalia bellirica and Terminalia chebula are used as the main ingredient in Triphala, a famous polyherbal formulation in Ayurvedic medicine and Thai folk medicine, because of their laxative, detoxifying, and rejuvenating effects. To clarify the phylogenetic relationships of medicinal Terminalia species (T. bellirica, T. chebula, and T. catappa) and authenticate their crude drugs, "Samo" and Triphala, nucleotide sequencing alignments in the internal transcribed spacer one-two (ITS 1-2) regions of Terminalia plants collected in Thailand were performed. The amplified fragments of Terminalia species were approximately 800 bp in length. To compare these sequences and DDBJ registered data, a molecular phylogenetic tree was constructed. Phylogenetic analysis clearly separated the sequences into two groups: Asian Terminalia and African Terminalia with some exceptions. In the analyzed sequences, the length of the ITS1-5.8S-ITS2 region was 674 bp in T. chebula, and 677 bp in T. bellirica and T. catappa. Eighty-one single nucleotide polymorphisms (SNPs) and nine insertion-deletions (indels) were observed, and the nucleotide sequences of this region showed species-specific sequences. Based on these differences, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and amplification refractory mutation system (ARMS) were applied to identify medicinal Terminalia species. Moreover, the ARMS method was chosen for fingerprinting analysis of Samo crude drugs and Triphala formulations because it was a fast, cost-effective, and reproducible approach. PMID:27040622

  19. Distribution of Pseudomonas Species in a Dairy Plant Affected by Occasional Blue Discoloration

    PubMed Central

    Lomonaco, Sara; Nucera, Daniele; Garoglio, Davide; Dalmasso, Alessandra; Civera, Tiziana

    2014-01-01

    During 2010 many cases of discoloration in mozzarella, popularly termed as blue mozzarella, have been reported to the attention of public opinion. Causes of the alteration were bacteria belonging to the genus Pseudomonas. The strong media impact of such cases has created confusion, not only among consumers, but also among experts. In order to help improving the knowledge on microbial ecology of this microorganism a study has been set up with the collaboration of a medium-sized dairy plant producing fresh mozzarella cheese, with occasional blue discoloration, conducting surveys and sampling in the pre-operational, operational and post-operational process phase, milk before and after pasteurization, water (n=12), environmental surfaces (n=22) and the air (n=27). A shelf life test was conducted on finished products stored at different temperatures (4-8°C). Among the isolates obtained from the microbiological analysis of the samples, 60 were subjected to biomolecular tests in order to confirm the belonging to Pseudomonas genus and to get an identification at species level by the amplification and sequencing of the gyrB gene. The results of microbiological tests demonstrated the presence of microorganisms belonging to the genus Pseudomonas along the entire production lane; molecular tests showed 7 different species among the 40 isolates identified. One particular species (Pseudomonas koreensis) was isolated from blue discolored mozzarella cheese and was indicated as the most relevant for the production plant, both for the distribution along the processing chain and for the consequences on the finished product. PMID:27800364

  20. Climate and host plant availability impact the future distribution of the bean leaf beetle (Cerotoma trifurcata).

    PubMed

    Berzitis, Emily A; Minigan, Jordan N; Hallett, Rebecca H; Newman, Jonathan A

    2014-09-01

    The bean leaf beetle, Cerotoma trifurcata, has become a major pest of soybean throughout its North American range. With a changing climate, there is the potential for this pest to further expand its distribution and become an increasingly severe pest in certain regions. To examine this possibility, we developed bioclimatic envelope models for both the bean leaf beetle, and its most important agronomic host plant, soybean (Glycine max). These two models were combined to examine the potential future pest status of the beetle using climate change projections from multiple general circulation models (GCMs) and climate change scenarios. Despite the broad tolerances of soybean, incorporation of host plant availability substantially decreased the suitable and favourable areas for the bean leaf beetle as compared to an evaluation based solely on the climate envelope of the beetle, demonstrating the importance of incorporating biotic interactions in these predictions. The use of multiple GCM-scenario combinations also revealed differences in predictions depending on the choice of GCM, with scenario choice having less of an impact. While the Norwegian model predicted little northward expansion of the beetle from its current northern range limit of southern Ontario and overall decreases in suitable and favourable areas over time, the Canadian and Russian models predict that much of Ontario and Quebec will become suitable for the beetle in the future, as well as Manitoba under the Russian model. The Russian model also predicts expansion of the suitable and favourable areas for the beetle over time. Two predictions that do not depend on our choice of GCM include a decrease in suitability of the Mississippi Delta region and continued favourability of the southeastern United States.

  1. Variation in n-Alkane Distributions of Modern Plants: Questioning Applications of n-Alkanes in Chemotaxonomy and Paleoecology

    NASA Astrophysics Data System (ADS)

    Bush, R. T.; McInerney, F. A.

    2010-12-01

    Long chain n-alkanes (n-C21 to n-C37) are synthesized as part of the epicuticular leaf wax of terrestrial plants and are among the most recognizable and widely used plant biomarkers. n-Alkane distributions have been utilized in previous studies on modern plant chemotaxonomy, testing whether taxa can be identified based on characteristic n-alkane profiles. Dominant n-alkanes (e.g. n-C27 or n-C31) have also been ascribed to major plant groups (e.g. trees or grasses respectively) and have been used in paleoecology studies to reconstruct fluctuations in plant functional types. However, many of these studies have been based on relatively few modern plant data; with the wealth of modern n-alkane studies, a more comprehensive analysis of n-alkanes in modern plants is now possible and can inform the usefulness of n-alkane distributions as paleoecological indicators. The work presented here is a combination of measurements made using plant leaves collected from the Chicago Botanic Garden and a compilation of published literature data from six continents. We categorized plants by type: angiosperms, gymnosperms, woody plants, forbs, grasses, ferns and pteridophytes, and mosses. We then quantified n-alkane distribution parameters such as carbon preference index (CPI), average chain length (ACL), and dispersion (a measure of the spread of the profile over multiple chain lengths) and used these to compare plant groups. Among all plants, one of the emergent correlations is a decrease in dispersion with increasing CPI. Within and among plant groups, n-alkane distributions show a very large range of variation, and the results show little or no correspondence between broad plant groups and a single dominant n-alkane or a ratio of n-alkanes. These findings are true both when data from six continents are combined and when plants from a given region are compared (North America). We also compared the n-alkane distributions of woody angiosperms, woody gymnosperms, and grasses with one

  2. SAGE III

    Atmospheric Science Data Center

    2016-06-15

    SAGE III Data and Information The Stratospheric Aerosol and Gas ... on the spacecraft. SAGE III produced L1 and L2 scientific data from 5/07/2002 until 12/31/2005. The flight of the second instrument is as ... Guide Documents:  Project Guide Data Products User's Guide  (PDF) Relevant Documents:  ...

  3. Discovery of Plant Phenolic Compounds That Act as Type III Secretion System Inhibitors or Inducers of the Fire Blight Pathogen, Erwinia amylovora

    PubMed Central

    Khokhani, Devanshi; Zhang, Chengfang; Li, Yan; Wang, Qi; Zeng, Quan; Yamazaki, Akihiro; Hutchins, William; Zhou, Shan-Shan

    2013-01-01

    Erwinia amylovora causes a devastating disease called fire blight in rosaceous plants. The type III secretion system (T3SS) is one of the important virulence factors utilized by E. amylovora in order to successfully infect its hosts. By using a green fluorescent protein (GFP) reporter construct combined with a high-throughput flow cytometry assay, a library of phenolic compounds and their derivatives was studied for their ability to alter the expression of the T3SS. Based on the effectiveness of the compounds on the expression of the T3SS pilus, the T3SS inhibitors 4-methoxy-cinnamic acid (TMCA) and benzoic acid (BA) and one T3SS inducer, trans-2-(4-hydroxyphenyl)-ethenylsulfonate (EHPES), were chosen for further study. Both the T3SS inhibitors (TMCA and BA) and the T3SS inducer (EHPES) were found to alter the expression of T3SS through the HrpS-HrpL pathway. Additionally, TMCA altered T3SS expression through the rsmBEa-RsmAEa system. Finally, we found that TMCA and BA weakened the hypersensitive response (HR) in tobacco by suppressing the T3SS of E. amylovora. In our study, we identified phenolic compounds that specifically targeted the T3SS. The T3SS inhibitor may offer an alternative approach to antimicrobial therapy by targeting virulence factors of bacterial pathogens. PMID:23770912

  4. Discovery of plant phenolic compounds that act as type III secretion system inhibitors or inducers of the fire blight pathogen, Erwinia amylovora.

    PubMed

    Khokhani, Devanshi; Zhang, Chengfang; Li, Yan; Wang, Qi; Zeng, Quan; Yamazaki, Akihiro; Hutchins, William; Zhou, Shan-Shan; Chen, Xin; Yang, Ching-Hong

    2013-09-01

    Erwinia amylovora causes a devastating disease called fire blight in rosaceous plants. The type III secretion system (T3SS) is one of the important virulence factors utilized by E. amylovora in order to successfully infect its hosts. By using a green fluorescent protein (GFP) reporter construct combined with a high-throughput flow cytometry assay, a library of phenolic compounds and their derivatives was studied for their ability to alter the expression of the T3SS. Based on the effectiveness of the compounds on the expression of the T3SS pilus, the T3SS inhibitors 4-methoxy-cinnamic acid (TMCA) and benzoic acid (BA) and one T3SS inducer, trans-2-(4-hydroxyphenyl)-ethenylsulfonate (EHPES), were chosen for further study. Both the T3SS inhibitors (TMCA and BA) and the T3SS inducer (EHPES) were found to alter the expression of T3SS through the HrpS-HrpL pathway. Additionally, TMCA altered T3SS expression through the rsmBEa-RsmAEa system. Finally, we found that TMCA and BA weakened the hypersensitive response (HR) in tobacco by suppressing the T3SS of E. amylovora. In our study, we identified phenolic compounds that specifically targeted the T3SS. The T3SS inhibitor may offer an alternative approach to antimicrobial therapy by targeting virulence factors of bacterial pathogens.

  5. High-throughput profiling of antibiotic resistance genes in drinking water treatment plants and distribution systems.

    PubMed

    Xu, Like; Ouyang, Weiying; Qian, Yanyun; Su, Chao; Su, Jianqiang; Chen, Hong

    2016-06-01

    Antibiotic resistance genes (ARGs) are present in surface water and often cannot be completely eliminated by drinking water treatment plants (DWTPs). Improper elimination of the ARG-harboring microorganisms contaminates the water supply and would lead to animal and human disease. Therefore, it is of utmost importance to determine the most effective ways by which DWTPs can eliminate ARGs. Here, we tested water samples from two DWTPs and distribution systems and detected the presence of 285 ARGs, 8 transposases, and intI-1 by utilizing high-throughput qPCR. The prevalence of ARGs differed in the two DWTPs, one of which employed conventional water treatments while the other had advanced treatment processes. The relative abundance of ARGs increased significantly after the treatment with biological activated carbon (BAC), raising the number of detected ARGs from 76 to 150. Furthermore, the final chlorination step enhanced the relative abundance of ARGs in the finished water generated from both DWTPs. The total enrichment of ARGs varied from 6.4-to 109.2-fold in tap water compared to finished water, among which beta-lactam resistance genes displayed the highest enrichment. Six transposase genes were detected in tap water samples, with the transposase gene TnpA-04 showing the greatest enrichment (up to 124.9-fold). We observed significant positive correlations between ARGs and mobile genetic elements (MGEs) during the distribution systems, indicating that transposases and intI-1 may contribute to antibiotic resistance in drinking water. To our knowledge, this is the first study to investigate the diversity and abundance of ARGs in drinking water treatment systems utilizing high-throughput qPCR techniques in China.

  6. High-throughput profiling of antibiotic resistance genes in drinking water treatment plants and distribution systems.

    PubMed

    Xu, Like; Ouyang, Weiying; Qian, Yanyun; Su, Chao; Su, Jianqiang; Chen, Hong

    2016-06-01

    Antibiotic resistance genes (ARGs) are present in surface water and often cannot be completely eliminated by drinking water treatment plants (DWTPs). Improper elimination of the ARG-harboring microorganisms contaminates the water supply and would lead to animal and human disease. Therefore, it is of utmost importance to determine the most effective ways by which DWTPs can eliminate ARGs. Here, we tested water samples from two DWTPs and distribution systems and detected the presence of 285 ARGs, 8 transposases, and intI-1 by utilizing high-throughput qPCR. The prevalence of ARGs differed in the two DWTPs, one of which employed conventional water treatments while the other had advanced treatment processes. The relative abundance of ARGs increased significantly after the treatment with biological activated carbon (BAC), raising the number of detected ARGs from 76 to 150. Furthermore, the final chlorination step enhanced the relative abundance of ARGs in the finished water generated from both DWTPs. The total enrichment of ARGs varied from 6.4-to 109.2-fold in tap water compared to finished water, among which beta-lactam resistance genes displayed the highest enrichment. Six transposase genes were detected in tap water samples, with the transposase gene TnpA-04 showing the greatest enrichment (up to 124.9-fold). We observed significant positive correlations between ARGs and mobile genetic elements (MGEs) during the distribution systems, indicating that transposases and intI-1 may contribute to antibiotic resistance in drinking water. To our knowledge, this is the first study to investigate the diversity and abundance of ARGs in drinking water treatment systems utilizing high-throughput qPCR techniques in China. PMID:26890482

  7. Frequency and Geographical Distribution of Plant-Parasitic Nematodes on Cotton in Georgia

    PubMed Central

    Baird, R. E.; Davis, R. F.; Alt, P. J.; Mullinix, B. G.; Padgett, G. B.

    1996-01-01

    A survey was conducted to examine the geographical distribution of plant-parasitic nematodes in Georgia cotton fields. A total of 778 fields in 11 Georgia counties were sampled from 1 September through 15 December 1995. Four nematode genera parasitic on cotton were found in this survey: Meloidogyne spp., Rotylenchulus sp., Hoplolaimus sp., and Belonolaimus sp. Meloidogyne spp. was present in 9% to 56% of the fields in individual counties. Rotylenchulus sp. was found in 10 counties, Hoplolaimus sp. was found in 6 counties, and Belonolaimus sp. was found in 2 counties. From all of the samples collected for this survey, Meloidogyne spp. were found in 31% of the samples, Rotylenchulus sp. was found in 14%, Hoplolaimus sp. was found in 7%, and Belonolaimus sp. was found in 0.3%. Burke County had the greatest number of fields infested by at least one of these genera (67%) and the greatest number of fields above Georgia's action thresholds (38%). Laurens County had the fewest fields where these genera were present (13%), and only 3% of fields had nematode populations above threshold levels. Data from samples collected from cotton fields and submitted by county agents from 1993 through 1994 were compiled to provide historical information about nematode distribution and population density. The results from this survey show that the major nematodes damaging to cotton are not present in all counties in Georgia. Counties in which cotton has historically been a major crop are likely to have higher levels of Meloidogyne spp., Hoplolaimus sp., and Rotylenchulus sp. in current cotton crops. Counties in which soybean has historically been a major crop are likely to have higher levels of Hoplolaimus sp. and Rotylenchulus sp. in current cotton crops. PMID:19277192

  8. Phenotypic plasticity influences the size, shape and dynamics of the geographic distribution of an invasive plant.

    PubMed

    Pichancourt, Jean-Baptiste; van Klinken, Rieks D

    2012-01-01

    Phenotypic plasticity has long been suspected to allow invasive species to expand their geographic range across large-scale environmental gradients. We tested this possibility in Australia using a continental scale survey of the invasive tree Parkinsonia aculeata (Fabaceae) in twenty-three sites distributed across four climate regions and three habitat types. Using tree-level responses, we detected a trade-off between seed mass and seed number across the moisture gradient. Individual trees plastically and reversibly produced many small seeds at dry sites or years, and few big seeds at wet sites and years. Bigger seeds were positively correlated with higher seed and seedling survival rates. The trade-off, the relation between seed mass, seed and seedling survival, and other fitness components of the plant life-cycle were integrated within a matrix population model. The model confirms that the plastic response resulted in average fitness benefits across the life-cycle. Plasticity resulted in average fitness being positively maintained at the wet and dry range margins where extinction risks would otherwise have been high ("Jack-of-all-Trades" strategy JT), and fitness being maximized at the species range centre where extinction risks were already low ("Master-of-Some" strategy MS). The resulting hybrid "Jack-and-Master" strategy (JM) broadened the geographic range and amplified average fitness in the range centre. Our study provides the first empirical evidence for a JM species. It also confirms mechanistically the importance of phenotypic plasticity in determining the size, the shape and the dynamic of a species distribution. The JM allows rapid and reversible phenotypic responses to new or changing moisture conditions at different scales, providing the species with definite advantages over genetic adaptation when invading diverse and variable environments. Furthermore, natural selection pressure acting on phenotypic plasticity is predicted to result in maintenance

  9. Phenotypic Plasticity Influences the Size, Shape and Dynamics of the Geographic Distribution of an Invasive Plant

    PubMed Central

    Pichancourt, Jean-Baptiste; van Klinken, Rieks D.

    2012-01-01

    Phenotypic plasticity has long been suspected to allow invasive species to expand their geographic range across large-scale environmental gradients. We tested this possibility in Australia using a continental scale survey of the invasive tree Parkinsonia aculeata (Fabaceae) in twenty-three sites distributed across four climate regions and three habitat types. Using tree-level responses, we detected a trade-off between seed mass and seed number across the moisture gradient. Individual trees plastically and reversibly produced many small seeds at dry sites or years, and few big seeds at wet sites and years. Bigger seeds were positively correlated with higher seed and seedling survival rates. The trade-off, the relation between seed mass, seed and seedling survival, and other fitness components of the plant life-cycle were integrated within a matrix population model. The model confirms that the plastic response resulted in average fitness benefits across the life-cycle. Plasticity resulted in average fitness being positively maintained at the wet and dry range margins where extinction risks would otherwise have been high (“Jack-of-all-Trades” strategy JT), and fitness being maximized at the species range centre where extinction risks were already low (“Master-of-Some” strategy MS). The resulting hybrid “Jack-and-Master” strategy (JM) broadened the geographic range and amplified average fitness in the range centre. Our study provides the first empirical evidence for a JM species. It also confirms mechanistically the importance of phenotypic plasticity in determining the size, the shape and the dynamic of a species distribution. The JM allows rapid and reversible phenotypic responses to new or changing moisture conditions at different scales, providing the species with definite advantages over genetic adaptation when invading diverse and variable environments. Furthermore, natural selection pressure acting on phenotypic plasticity is predicted to result in

  10. Distribution pathways of hexachlorocyclohexane isomers in a soil-plant-air system. A case study with Cynara scolymus L. and Erica sp. plants grown in a contaminated site.

    PubMed

    Pereira, R Calvelo; Monterroso, C; Macías, F; Camps-Arbestain, M

    2008-09-01

    This study focuses on the main routes of distribution and accumulation of different hexachlorocyclohexane (HCH) isomers (mainly alpha-, beta-, gamma- and delta-HCH) in a soil-plant-air system. A field assay was carried out with two plant species, Cynara scolymus L. and Erica sp., which were planted either: (i) directly in the HCH-contaminated soil; or (ii) in pots filled with uncontaminated soil, which were placed in the HCH-contaminated soil. Both plant species accumulated HCH in their tissues, with relatively higher accumulation in above-ground biomass than in roots. The beta-HCH isomer was the main isomer in all plant tissues. Adsorption of HCH by the roots from contaminated soil (soil-->root pathway) and adsorption through the aerial biomass from either the surrounding air, following volatilization of the contaminant (soil-->air-->shoot pathway), and/or contact with air-suspended particles contaminated with HCH (soil particles-->shoot pathway) were the main mechanisms of accumulation. These results may have important implications for the use of plants for reducing the transfer of contaminants via the atmosphere.

  11. Circular distribution pattern of plant modulars and endophagous herbivory within tree crowns: the impact of roadside light conditions.

    PubMed

    Dai, Xiao-Hua; Xu, Jia-Sheng; Ding, Xing-Lu

    2013-01-01

    The circular distributions of plant modulars (branches, leaves) and endophagous herbivory (mines, galls) were investigated within the crowns of four dominant Fagaceae trees in a subtropical evergreen broadleaf forest at Jiulianshan National Nature Reserve, Jiangxi, China. The hypothesis is that more plant modulars and more endophagous herbivory should occur in the crown area perpendicular to the roads. Circular statistical techniques were used to verify new patterns of the impact of roads on plants and insects. The results confirmed that the roadside light environments had larger impacts on the circular distribution patterns of plant modulars than those of leaf herbivores. For herbivores, the impact of light was larger on mine distribution than on gall distribution. The branches of all four tree species were concentrated in the direction perpendicular to the roads. In the preferred direction, branches were longer and higher. More leaves, more mines, and more galls were found surrounding the preferred branch direction. In general, leaf miners and leaf gallers preferred leaves in the sun over those in the shade; however, leaf gallers had a lower degree of preference for sun than leaf miners. Different endphagous insects also showed clear interspecific differences in sun/shade leaf selection. PMID:24794427

  12. Distribution and population structure of the anther smut Microbotryum silenes-acaulis parasitizing an arctic-alpine plant.

    PubMed

    Bueker, Britta; Eberlein, Chris; Gladieux, Pierre; Schaefer, Angela; Snirc, Alodie; Bennett, Dominic J; Begerow, Dominik; Hood, Michael E; Giraud, Tatiana

    2016-02-01

    Cold-adapted organisms with current arctic-alpine distributions have persisted during the last glaciation in multiple ice-free refugia, leaving footprints in their population structure that contrast with temperate plants and animals. However, pathogens that live within hosts having arctic-alpine distributions have been little studied. Here, we therefore investigated the geographical range and population structure of a fungus parasitizing an arctic-alpine plant. A total of 1437 herbarium specimens of the plant Silene acaulis were examined, and the anther smut pathogen Microbotryum silenes-acaulis was present throughout the host's geographical range. There was significantly greater incidence of anther smut disease in more northern latitudes and where the host locations were less dense, indicating a major influence of environmental factors and/or host demographic structure on the pathogen distribution. Genetic analyses with seven microsatellite markers on recent collections of 195 M. silenes-acaulis individuals revealed three main genetic clusters, in North America, northern Europe and southern Europe, likely corresponding to differentiation in distinct refugia during the last glaciation. The lower genetic diversity in northern Europe indicates postglacial recolonization northwards from southern refugia. This study combining herbarium surveys and population genetics thus uniquely reveals the effects of climate and environmental factors on a plant pathogen species with an arctic-alpine distribution. PMID:26671732

  13. Fractal Features of Soil Particle Size Distribution Under Different Plant Communities in the Forested Region of Mountain Yimeng, China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to explore the effect of changes in plant communities and land use on soil properties, as a result of anthropogenic disturbances, we apply the theory of fractals and soil physics as a means to better quantify changes in particle-size distribution (PSD) and soil porosity. Fractal dimension a...

  14. [Effects of topography on the diversity and distribution pattern of ground plants in karst montane forests in Southwest Guangxi, China].

    PubMed

    Yuan, Tie-Xiang; Zhang, He-Ping; Ou, Zhi-Yang; Tan, Yi-Bo

    2014-10-01

    Covariance analysis, curve-fitting, and canonical correspondence analysis (CCA) were used to explore the effects of topographic factors on the plant diversity and distribution patterns of ground flora with different growth forms in the karst mountains of Southwest Guangxi, China. A total of 152 ground plants were recorded. Among them, 37 species were ferns, 44 species herbs, 9 species lianas, and 62 species shrubs. Covariance analysis revealed that altitude significantly correlated with the individual number and richness of ground plants, and slope aspect had a significant effect on richness. Statistical analyses showed a highly significant nonlinear correlation between the individual number or richness of ground plants and altitude. Results of CCA revealed that slope aspect had a significant effect on the distribution pattern of ferns, and slope had a significant effect on the distribution patterns of herbs, lianas and shrubs. Ferns were more sensitive than herbs, lianas and shrubs to changes in heat and soil water caused by aspect. The effect of slope was stronger than that of elevation on soil water and nutrients, and it was the most important topographic factor that affected the distribution patterns of herbs, lianas and shrubs in this region.

  15. Distribution and population structure of the anther smut Microbotryum silenes-acaulis parasitizing an arctic-alpine plant.

    PubMed

    Bueker, Britta; Eberlein, Chris; Gladieux, Pierre; Schaefer, Angela; Snirc, Alodie; Bennett, Dominic J; Begerow, Dominik; Hood, Michael E; Giraud, Tatiana

    2016-02-01

    Cold-adapted organisms with current arctic-alpine distributions have persisted during the last glaciation in multiple ice-free refugia, leaving footprints in their population structure that contrast with temperate plants and animals. However, pathogens that live within hosts having arctic-alpine distributions have been little studied. Here, we therefore investigated the geographical range and population structure of a fungus parasitizing an arctic-alpine plant. A total of 1437 herbarium specimens of the plant Silene acaulis were examined, and the anther smut pathogen Microbotryum silenes-acaulis was present throughout the host's geographical range. There was significantly greater incidence of anther smut disease in more northern latitudes and where the host locations were less dense, indicating a major influence of environmental factors and/or host demographic structure on the pathogen distribution. Genetic analyses with seven microsatellite markers on recent collections of 195 M. silenes-acaulis individuals revealed three main genetic clusters, in North America, northern Europe and southern Europe, likely corresponding to differentiation in distinct refugia during the last glaciation. The lower genetic diversity in northern Europe indicates postglacial recolonization northwards from southern refugia. This study combining herbarium surveys and population genetics thus uniquely reveals the effects of climate and environmental factors on a plant pathogen species with an arctic-alpine distribution.

  16. Ecophysiology of wetland plant roots: A modelling comparison of aeration in relation to species distribution

    USGS Publications Warehouse

    Sorrell, B.K.; Mendelssohn, I.A.; McKee, K.L.; Woods, R.A.

    2000-01-01

    This study examined the potential for inter-specific differences in root aeration to determine wetland plant distribution in nature. We compared aeration in species that differ in the type of sediment and depth of water they colonize. Differences in root anatomy, structure and physiology were applied to aeration models that predicted the maximum possible aerobic lengths and development of anoxic zones in primary adventitious roots. Differences in anatomy and metabolism that provided higher axial fluxes of oxygen allowed deeper root growth in species that favour more reducing sediments and deeper water. Modelling identified factors that affected growth in anoxic soils through their effects on aeration. These included lateral root formation, which occurred at the expense of extension of the primary root because of the additional respiratory demand they imposed, reducing oxygen fluxes to the tip and stele, and the development of stelar anoxia. However, changes in sediment oxygen demand had little detectable effect on aeration in the primary roots due to their low wall permeability and high surface impedance, but appeared to reduce internal oxygen availability by accelerating loss from laterals. The development of pressurized convective gas flow in shoots and rhizomes was also found to be important in assisting root aeration, as it maintained higher basal oxygen concentrations at the rhizome-root junctions in species growing into deep water. (C) 2000 Annals of Botany Company.

  17. Numerical modelling of distribution the discharged heat water from thermal power plant on the aquatic environment

    NASA Astrophysics Data System (ADS)

    Issakhov, Alibek

    2016-06-01

    The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler.

  18. Radiation dose distribution for workers in South Korean nuclear power plants.

    PubMed

    Lee, Byoung-il; Kim, So-i; Suh, Dong-hee; Jin, Young-woo; Kim, Jeong-in; Choi, Hoon; Lim, Young-khi

    2010-07-01

    A total of 33 680 nuclear power plants (NPPs) workers were monitored and recorded from 1990 to 2007. According to the record, the average individual radiation dose has been decreasing continually from 3.20 mSv man(-1) in 1990 to 1.12 mSv man(-1) at the end of 2007. After the International Commission on Radiological Protection 60 recommendation was generalised in South Korea, no NPP workers received >20 mSv radiation, and the numbers of relatively highly exposed workers have been decreasing continuously. The age distribution of radiation workers in NPPs was composed mainly of 20-30 y olds (83 %) for 1990-1994 and 30-40 y olds (75 %) for 2003-2007. The difference in individual average dose by age was not significant. Most (77 %) of the NPP radiation exposures from 1990 to 2007 occurred mostly during the refueling period. With regard to exposure type, the majority of exposures was external exposures, representing 95 % of the total exposures, whereas internal exposures represented only 5 %. External effective dose was affected mainly by gamma radiation exposure, with an insignificant amount of neutron exposure. As for internal effective dose, tritium in the pressurised heavy water reactor was the biggest cause of exposure.

  19. The distribution of acetylcholine in the Malayan jack-fruit plant, Artocarpus integra.

    PubMed

    LIN, R C

    1957-09-01

    The distribution of acetylcholine in the seeds and leaves of the Malayan Jack-fruit plant, Artocarpus integra, has been studied with the view to obtaining evidence for the site of its formation. The terminal growing leaves on the side branches had a very high concentration of acetylcholine (770 mug./g.), while the acetylcholine content of the other leaves on the same branch progressively decreased with age. The total amount of acetylcholine stored in the terminal growing leaves was only 42 mug., but in the second leaves which had grown nearly to their full size it was 540 mug. From the third leaves, the amount of acetylcholine stored gradually decreased. The midribs and the secondary veins of the leaves when combined had a higher concentration of acetylcholine than had the blades. The acetylcholine concentration of the pith of the stem was 4.2 times higher than that of the cortex-phloem layer while that of the xylem layer was the lowest; in the root the pith had a value only one-seventh of the cortex. The younger part of the pith and the cortex-phloem layers of the stem contained more acetylcholine than the older parts. These findings support the view that the acetylcholine is synthesized in the growing leaves. An unusual lenticel-like structure in the cortex layer of the root contained more acetylcholine than the surrounding tissue.

  20. Distribution and diversity of biosurfactant-producing bacteria in a wastewater treatment plant.

    PubMed

    Ndlovu, Thando; Khan, Sehaam; Khan, Wesaal

    2016-05-01

    The distribution and diversity of culturable biosurfactant-producing bacteria were investigated in a wastewater treatment plant (WWTP) using the Shannon and Simpson's indices. Twenty wastewater samples were analysed, and from 667 isolates obtained, 32 were classified as biosurfactant producers as they reduced the surface tension of the culture medium (71.1 mN/m), with the lowest value of 32.1 mN/m observed. Certain isolates also formed stable emulsions with diesel, kerosene and mineral oils. The 16S ribosomal RNA (rRNA) analysis classified the biosurfactant producers into the Aeromonadaceae, Bacillaceae, Enterobacteriaceae, Gordoniaceae and the Pseudomonadaceae families. In addition, numerous isolates carried the surfactin 4'-phosphopantetheinyl transferase (sfp), rhamnosyltransferase subunit B (rhlB) and bacillomycin C (bamC) genes involved in the biosynthesis of surfactin, rhamnolipid and bacillomycin, respectively. While, biosurfactant-producing bacteria were found at all sampling points in the WWTP, the Simpson's diversity (1 - D) and the Shannon-Weaver (H) indices revealed an increase in bacterial diversity in the influent samples (0.8356 and 2.08), followed by the effluent (0.8 and 1.6094) and then the biological trickling filter (0.7901 and 1.6770) samples. Numerous biosurfactant-producing bacteria belonging to diverse genera are thus present throughout a WWTP.

  1. DISTRIBUTION OF SELECTED INVASIVE PLANTS IN RIPARIAN ECOSYSTEMS OF THE WESTERN UNITED STATES

    EPA Science Inventory

    Riparian ecosystems typically exhibit high levels of plant species richness, physical disturbance, and interconnectedness; characteristics that may favor establishment and spread of invasive plant species. To assess the magnitude of this invasion, we organized an extensive surve...

  2. Effect of plant cover on distribution of soil organic matter pools

    NASA Astrophysics Data System (ADS)

    Gunina, Anna; Kuzyakov, Yakov; Ryzhova, Irina

    2013-04-01

    Numerous studies reported that quality and quantity of primary production and also the rate of litter decomposition determine the carbon (C) content and its distribution in soils. Our objective was to examine how the type of plant cover affects C sequestration in the following pools: unprotected, spatial inaccessible, interacting with silt and clay, and biochemically protected SOM. The large lysimeters of Moscow State University allowed quantification of C stocks under broadleaf forest (Acer platanoides and Quercus robur), coniferous forest (Picea abies) and agricultural crops (9-field rotation), while other soil forming factors affecting SOC content were identical. In 1965 the lysimeters (S=9 m2, depth=1.5 m) were filled with carbonate free clay loam taken in Moscow region, originated from the Valday glaciation, and plant communities listed above were planted. We collected soil samples from the mineral horizons, from 0-5 cm depth, in spring 2012. The soils were physically separated by combination of the particle size and density fractionations (8 fractions in total), and C and N contents were analyzed. The total C and N contents in non-fractionated soil were higher under broadleaf forest (66 and 3.1 g kg-1), than under coniferous forest (34.5 and 1.23 g kg-1) and agricultural crops (13.7 and 0.9 g kg-1). Under forests 45-50% of Ctotal and 30% of Ntotal were in the unprotected pool, in agricultural soil these percentages were in 3 times less. The greatest portions of protected C were in spatial inaccessible pool: 28, 32 and 40% of the Ctotal for broadleaf forest, coniferous forest and agricultural crops, respectively. However, the total C amount in this pool under agricultural crops was in 3 times less, than under forests. This is indicative for the loss of C-rich macroaggregates and an increase of C-depleted microaggregates in agricultural soils due to the plowing. The amounts of C, stabilized by interactions with silt and clay, were nearly the same (3-6 g kg-1

  3. Ce(III) and Ce(IV) (re)distribution and fractionation in a laterite profile from Madagascar: Insights from in situ XANES spectroscopy at the Ce LIII-edge

    NASA Astrophysics Data System (ADS)

    Janots, Emilie; Bernier, Felix; Brunet, Fabrice; Muñoz, Manuel; Trcera, Nicolas; Berger, Alfons; Lanson, Martine

    2015-03-01

    The distribution of trivalent and tetravalent cerium, Ce(III) and Ce(IV) respectively, in a lateritic profile from Madagascar, has been characterized by X-ray-absorption near-edge structure (XANES) spectroscopy at the Ce LIII-edge on the LUCIA beamline (SOLEIL synchrotron, France). XANES spectra were acquired on bulk-rock samples as well as on specific lateritic minerals or polymineral zones (in-situ measurements) of the tonalite bedrock and the three overlying weathered horizons (C-, B- and A-horizons). Geochemically, the bedrock, and the A- and C-horizons show similar rare earth element content (REE = 363-405 mg/kg). They also display the same positive Ce-anomaly (CeCN/Ce∗ = 1.12-1.45), which is therefore likely to be inherited from the bedrock. In the B-horizon, the higher REE content (REE = 2194 mg/kg) and the larger Ce-anomaly (CeCN/Ce∗ = 4.26) are consistent with an accumulation zone caused by the evaporation of groundwater during the dry season. There is a good agreement between the Ce(III)/Cetotal ratio (XCe(III)) deduced from the positive Ce-anomaly (bulk-rock geochemical data) and that derived from XANES spectroscopy on the same bulk-rock samples (BR-XCe(III)-XANES) in the bedrock, and the C- and B-horizons. In the A-horizon, XANES measurements on bulk rock and minerals revealed a higher BR-XCe(III)-XANES (up to 100%) compared to the XCe(III) deduced from geochemical data (XCe(III) = 79%). The preservation of a positive Ce-anomaly in the A-horizon suggests that the Ce mobilization and redistribution during weathering occurred with no significant Ce fractionation from other trivalent REE. Remarkably, the only investigated sample where cerianite is observed belongs to the B-horizon. Within this horizon, Ce oxidation state varies depending on the microstructural position (porosity, cracks, clay-rich groundmass). The highest Ce(IV) concentrations are measured in cerianite (and aluminophosphates) localized in pores at the vicinity of Mn-rich domains (XCe(III

  4. Ecological niche modeling of coastal dune plants and future potential distribution in response to climate change and sea level rise.

    PubMed

    Mendoza-González, Gabriela; Martínez, M Luisa; Rojas-Soto, Octavio R; Vázquez, Gabriela; Gallego-Fernández, Juan B

    2013-08-01

    Climate change (CC) and sea level rise (SLR) are phenomena that could have severe impacts on the distribution of coastal dune vegetation. To explore this we modeled the climatic niches of six coastal dunes plant species that grow along the shoreline of the Gulf of Mexico and the Yucatan Peninsula, and projected climatic niches to future potential distributions based on two CC scenarios and SLR projections. Our analyses suggest that distribution of coastal plants will be severely limited, and more so in the case of local endemics (Chamaecrista chamaecristoides, Palafoxia lindenii, Cakile edentula). The possibilities of inland migration to the potential 'new shoreline' will be limited by human infrastructure and ecosystem alteration that will lead to a 'coastal squeeze' of the coastal habitats. Finally, we identified areas as future potential refuges for the six species in central Gulf of Mexico, and northern Yucatán Peninsula especially under CC and SLR scenarios. PMID:23625760

  5. Ecological niche modeling of coastal dune plants and future potential distribution in response to climate change and sea level rise.

    PubMed

    Mendoza-González, Gabriela; Martínez, M Luisa; Rojas-Soto, Octavio R; Vázquez, Gabriela; Gallego-Fernández, Juan B

    2013-08-01

    Climate change (CC) and sea level rise (SLR) are phenomena that could have severe impacts on the distribution of coastal dune vegetation. To explore this we modeled the climatic niches of six coastal dunes plant species that grow along the shoreline of the Gulf of Mexico and the Yucatan Peninsula, and projected climatic niches to future potential distributions based on two CC scenarios and SLR projections. Our analyses suggest that distribution of coastal plants will be severely limited, and more so in the case of local endemics (Chamaecrista chamaecristoides, Palafoxia lindenii, Cakile edentula). The possibilities of inland migration to the potential 'new shoreline' will be limited by human infrastructure and ecosystem alteration that will lead to a 'coastal squeeze' of the coastal habitats. Finally, we identified areas as future potential refuges for the six species in central Gulf of Mexico, and northern Yucatán Peninsula especially under CC and SLR scenarios.

  6. Distribution and Transmission of Medicinal Plant Knowledge in the Andean Highlands: A Case Study from Peru and Bolivia

    PubMed Central

    Mathez-Stiefel, Sarah-Lan; Vandebroek, Ina

    2012-01-01

    This paper presents a study of patterns in the distribution and transmission of medicinal plant knowledge in rural Andean communities in Peru and Bolivia. Interviews and freelisting exercises were conducted with 18 households at each study site. The amount of medicinal plant knowledge of households was compared in relation to their socioeconomic characteristics. Cluster analysis was applied to identify households that possessed similar knowledge. The different modes of knowledge transmission were also assessed. Our study shows that while the amount of plant knowledge is determined by individual motivation and experience, the type of knowledge is influenced by the community of residence, age, migratory activity, and market integration. Plant knowledge was equally transmitted vertically and horizontally, which indicates that it is first acquired within the family but then undergoes transformations as a result of subsequent contacts with other knowledge sources, including age peers. PMID:22203885

  7. Response of Potato Tuber Number and Spatial Distribution to Plant Density in Different Growing Seasons in Southwest China.

    PubMed

    Zheng, Shun-Lin; Wang, Liang-Jun; Wan, Nian-Xin; Zhong, Lei; Zhou, Shao-Meng; He, Wei; Yuan, Ji-Chao

    2016-01-01

    The aim of this study was to explore the effects of different density treatments on potato spatial distribution and yield in spring and fall. Plant density influenced yield and composition, horizontal, and vertical distribution distances between potato tubers, and spatial distribution position of tuber weights. The results indicated that: (1) Spring potato yield had a convex quadratic curve relationship with density, and the highest value was observed at 15.75 × 10(4) tubers per hectare. However, the yield of fall potatoes showed a linear relationship with plant density, and the highest value was observed at 18 × 10(4) tubers per hectare; (2) Density had a greater influence on the tuber weight of spring potatoes and fruit number of single fall potatoes; (3) The number of potato tubers in the longitudinal concentration exhibited a negative linear relationship with density, whereas the average vertical distribution distance of tubers exhibited a positive incremental hyperbolic relationship. For spring and fall potato tubers, the maximum distances were 8.4152 and 6.3316 cm, and the minimum distances 8.7666 and 6.9366 cm, respectively; and (4) Based on the artificial neural network model of the spatial distribution of tuber weight, density mainly affected the number and spatial distribution of tubers over 80 g. Tubers over 80 g were mainly distributed longitudinally (6-10 cm) and transversely (12-20 cm) within the high density treatment, and the transverse distribution scope and number of tubers over 80 g were reduced significantly. Spring potato tubers over 80 g grown at the lowest density were mainly distributed between 12 and 20 cm, whereas those at the highest density were primarily distributed between 10 and 15 cm.

  8. Response of Potato Tuber Number and Spatial Distribution to Plant Density in Different Growing Seasons in Southwest China.

    PubMed

    Zheng, Shun-Lin; Wang, Liang-Jun; Wan, Nian-Xin; Zhong, Lei; Zhou, Shao-Meng; He, Wei; Yuan, Ji-Chao

    2016-01-01

    The aim of this study was to explore the effects of different density treatments on potato spatial distribution and yield in spring and fall. Plant density influenced yield and composition, horizontal, and vertical distribution distances between potato tubers, and spatial distribution position of tuber weights. The results indicated that: (1) Spring potato yield had a convex quadratic curve relationship with density, and the highest value was observed at 15.75 × 10(4) tubers per hectare. However, the yield of fall potatoes showed a linear relationship with plant density, and the highest value was observed at 18 × 10(4) tubers per hectare; (2) Density had a greater influence on the tuber weight of spring potatoes and fruit number of single fall potatoes; (3) The number of potato tubers in the longitudinal concentration exhibited a negative linear relationship with density, whereas the average vertical distribution distance of tubers exhibited a positive incremental hyperbolic relationship. For spring and fall potato tubers, the maximum distances were 8.4152 and 6.3316 cm, and the minimum distances 8.7666 and 6.9366 cm, respectively; and (4) Based on the artificial neural network model of the spatial distribution of tuber weight, density mainly affected the number and spatial distribution of tubers over 80 g. Tubers over 80 g were mainly distributed longitudinally (6-10 cm) and transversely (12-20 cm) within the high density treatment, and the transverse distribution scope and number of tubers over 80 g were reduced significantly. Spring potato tubers over 80 g grown at the lowest density were mainly distributed between 12 and 20 cm, whereas those at the highest density were primarily distributed between 10 and 15 cm. PMID:27092146

  9. Response of Potato Tuber Number and Spatial Distribution to Plant Density in Different Growing Seasons in Southwest China

    PubMed Central

    Zheng, Shun-Lin; Wang, Liang-Jun; Wan, Nian-Xin; Zhong, Lei; Zhou, Shao-Meng; He, Wei; Yuan, Ji-Chao

    2016-01-01

    The aim of this study was to explore the effects of different density treatments on potato spatial distribution and yield in spring and fall. Plant density influenced yield and composition, horizontal, and vertical distribution distances between potato tubers, and spatial distribution position of tuber weights. The results indicated that: (1) Spring potato yield had a convex quadratic curve relationship with density, and the highest value was observed at 15.75 × 104 tubers per hectare. However, the yield of fall potatoes showed a linear relationship with plant density, and the highest value was observed at 18 × 104 tubers per hectare; (2) Density had a greater influence on the tuber weight of spring potatoes and fruit number of single fall potatoes; (3) The number of potato tubers in the longitudinal concentration exhibited a negative linear relationship with density, whereas the average vertical distribution distance of tubers exhibited a positive incremental hyperbolic relationship. For spring and fall potato tubers, the maximum distances were 8.4152 and 6.3316 cm, and the minimum distances 8.7666 and 6.9366 cm, respectively; and (4) Based on the artificial neural network model of the spatial distribution of tuber weight, density mainly affected the number and spatial distribution of tubers over 80 g. Tubers over 80 g were mainly distributed longitudinally (6–10 cm) and transversely (12–20 cm) within the high density treatment, and the transverse distribution scope and number of tubers over 80 g were reduced significantly. Spring potato tubers over 80 g grown at the lowest density were mainly distributed between 12 and 20 cm, whereas those at the highest density were primarily distributed between 10 and 15 cm. PMID:27092146

  10. Discovery of cyclotides in the fabaceae plant family provides new insights into the cyclization, evolution, and distribution of circular proteins.

    PubMed

    Poth, Aaron G; Colgrave, Michelle L; Philip, Reynold; Kerenga, Bomai; Daly, Norelle L; Anderson, Marilyn A; Craik, David J

    2011-04-15

    Cyclotides are plant proteins whose defining structural features are a head-to-tail cyclized backbone and three interlocking disulfide bonds, which in combination are known as a cyclic cystine knot. This unique structural motif confers cyclotides with exceptional resistance to proteolysis. Their endogenous function is thought to be as plant defense agents, associated with their insecticidal and larval growth-inhibitory properties. However, in addition, an array of pharmaceutically relevant biological activities has been ascribed to cyclotides, including anti-HIV, anthelmintic, uterotonic, and antimicrobial effects. So far, >150 cyclotides have been elucidated from members of the Rubiaceae, Violaceae, and Cucurbitaceae plant families, but their wider distribution among other plant families remains unclear. Clitoria ternatea (Butterfly pea) is a member of plant family Fabaceae and through its usage in traditional medicine to aid childbirth bears similarity to Oldenlandia affinis, from which many cyclotides have been isolated. Using a combination of nanospray and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) analyses, we examined seed extracts of C. ternatea and discovered cyclotides in the Fabaceae, the third-largest family of flowering plants. We characterized 12 novel cyclotides, thus expanding knowledge of cyclotide distribution and evolution within the plant kingdom. The discovery of cyclotides containing novel sequence motifs near the in planta cyclization site has provided new insights into cyclotide biosynthesis. In particular, MS analyses of the novel cyclotides from C. ternatea suggest that Asn to Asp variants at the cyclization site are more common than previously recognized. Moreover, this study provides impetus for the examination of other economically and agriculturally significant species within Fabaceae, now the largest plant family from which cyclotides have been described. PMID:21194241

  11. Discovery of cyclotides in the fabaceae plant family provides new insights into the cyclization, evolution, and distribution of circular proteins.

    PubMed

    Poth, Aaron G; Colgrave, Michelle L; Philip, Reynold; Kerenga, Bomai; Daly, Norelle L; Anderson, Marilyn A; Craik, David J

    2011-04-15

    Cyclotides are plant proteins whose defining structural features are a head-to-tail cyclized backbone and three interlocking disulfide bonds, which in combination are known as a cyclic cystine knot. This unique structural motif confers cyclotides with exceptional resistance to proteolysis. Their endogenous function is thought to be as plant defense agents, associated with their insecticidal and larval growth-inhibitory properties. However, in addition, an array of pharmaceutically relevant biological activities has been ascribed to cyclotides, including anti-HIV, anthelmintic, uterotonic, and antimicrobial effects. So far, >150 cyclotides have been elucidated from members of the Rubiaceae, Violaceae, and Cucurbitaceae plant families, but their wider distribution among other plant families remains unclear. Clitoria ternatea (Butterfly pea) is a member of plant family Fabaceae and through its usage in traditional medicine to aid childbirth bears similarity to Oldenlandia affinis, from which many cyclotides have been isolated. Using a combination of nanospray and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) analyses, we examined seed extracts of C. ternatea and discovered cyclotides in the Fabaceae, the third-largest family of flowering plants. We characterized 12 novel cyclotides, thus expanding knowledge of cyclotide distribution and evolution within the plant kingdom. The discovery of cyclotides containing novel sequence motifs near the in planta cyclization site has provided new insights into cyclotide biosynthesis. In particular, MS analyses of the novel cyclotides from C. ternatea suggest that Asn to Asp variants at the cyclization site are more common than previously recognized. Moreover, this study provides impetus for the examination of other economically and agriculturally significant species within Fabaceae, now the largest plant family from which cyclotides have been described.

  12. [Aerosol size distribution of organic carbon and elemental carbon on the top of coke oven and in the plant area].

    PubMed

    Liu, Xiao-Feng; Peng, Lin; Bai, Hui-Ling; Mu, Ling; Song, Chong-Fang

    2013-08-01

    In order to investigate the characteristic of organic carbon (OC) and elemental carbon (EC) in particles on the top of coke oven and in the plant area, the particle matter samples of five size fraction including < or = 1.4 microm, 1.4-2.1 microm, 2.1-4.2 microm, 4.2-10.2 microm and > or = 10.2 microm were collected using Staplex234 cascade impactor, and OC and EC were analyzed by Elementar Analysensysteme GmbH vario EL cube. The mass concentrations of OC and EC associated with TSP on the top of coke oven were 291.6 microg x m(-3) and 255.1 microg x m(-3), while those in the plant area were 377.8 microg x m(-3) and 151.7 microg x m(-3). The mass concentration of secondary organic carbon (SOC) in particles with size of < or = 1.4 microm was 147.3 microg x m(-3) in the plant area. The value of OC/EC in particles less than 2.1 microm was 1.3 on the top of coke oven. The mass concentration of EC in TSP in the plant area was lower than that on the top of coke oven, while the mass concentration of OC in the plant area was significantly higher than that on the top of coke oven. The mass concentrations of OC and EC associated with particles less than 10.2 microm in the plant area were far higher than those in the atmosphere of area where the coke plant is located. The OC and EC in particles, which were collected both on the top of coke oven and in the plant area, were mainly enriched in fine particles. The size distribution of OC showed a clear distinction between the coke oven top and the plant area, which revealed that OC in the plant area was more preferably enriched in fine particles than that on the top of coke oven, and the same size distribution of EC was found on the top of coke oven and in the plant area. In the plant area, the mass concentration of SOC and the contribution of SOC to OC increased with the decreasing diameter in particles with diameter of less than 10.2 microm.

  13. SPECIES COMPOSITION, DISTRIBUTION, LIFE FORMS AND FOLK NOMENCLATURE OF FOREST AND COMMON LAND PLANTS OF WESTERN CHITWAN, NEPAL

    PubMed Central

    Dangol, D. R.

    2012-01-01

    This paper enumerates 349 plant species belonging to 77 families of vascular plants collected in the winter seasons of 1996 and 2000 by the flora teams of the Population and Ecology Research Laboratory, Nepal. Of the total species, 249 species belong to dicotyledons, 87 species to monocotyledons and 13 species to pteridophytes. Among the families, dicotyledons contributed the highest number of families (55 in number) followed by monocotyledons and pteridophytes. In the study areas, species composition varies with the type of habitats in the study plots. Some species are unique in distribution. The highest unique species are contributed by common lands (87 spp.), followed by the Chitwan National Park forest (36 spp.) and Tikauli forest (32 spp.). Ageratum houstonianum Mill., Cynodon dactylon (L.) Pers., Imperata cylindrica (L.) Beauv., Rungia parviflora (Retz.) Nees, Saccharum spontaneum L. and Thelypteris auriculata (J. Sm.) K. Iwats are the most common species across all the research blocks. Of the listed plants, many plants have local names either in Nepalese or other tribal languages. Plants are named in different ways on the basis of habit, habitat, smell, taste, and morphological characters of the plants, which are also the basis of nomenclature in plant taxonomy. PMID:22962539

  14. The uptake and distribution of cadmium in tomato plants as affected by ethylenediaminetetraacetic acid and 2,4-dinitrophenol.

    PubMed

    Wolterbeek, H T; van der Meer, A; de Bruin, M

    1988-01-01

    The uptake and distribution of cadmium in tomato plants (Lycopersicon esculentum, Mill, cv. Tiny Tim) were examined with and without the presence of ethylenediaminetetraacetic acid (EDTA) as chelating agent and 2,4-dinitrophenol (DNP) as metabolic inhibitor. Eight-week-old intact and derooted tomato seedlings were used in hydroculture experiments with cadmium applied as (115)Cd(NO(3))(2) in a range of concentrations. Measurements of the (115)Cd content of roots, stems and leaves were carried out by gamma-ray spectroscopy. The data showed that applications of both EDTA and DNP resulted in reduced total Cd accumulation in the plants, but relatively enhanced Cd transport into the above-ground plant parts. The Cd mobility in the transport channels in the shoots was increased by EDTA in both intact and derooted plants. Application of DNP leads to increased relative Cd import to leaves in derooted plants, but a reduced import into leaves of intact plants. These results suggest that Cd-complexes are formed in root cells before root-to-shoot transport. Furthermore, initial Cd uptake may be associated with adsorption on the negative charges of the cell walls of the root system. The high Cd mobility in shoots, in experiments with intact plants and Cd-EDTA application, indicates the possibility of simultaneous uptake of Cd and EDTA, possibly as a Cd-EDTA complex. PMID:15092498

  15. The distribution of gamma-emitting radionuclides in surface subtidal sediments near the Sellafield plant

    NASA Astrophysics Data System (ADS)

    Jones, D. G.; Roberts, P. D.; Miller, J. M.

    1988-08-01

    Detailed distributions of total gamma activity, 137Cs, 106Ru and 95Zr + 95Nb in surface seabed sediments near the Sellafield plant are presented. The results are derived from a towed seabed gamma-ray spectrometer survey in September, 1982. All the distributions are similar, with contours of equal activity parallel to the coast defining a 'ridge' of higher activity which is displaced northwards relative to the outfall. This pattern appears to be largely a response to the transport of particle-associated radioeffluent modified in places by the type of seabed sediment present. At greater distance from Sellafield, the uptake of nuclides from solution seems to be more important. Nuclide concentrations decrease with increasing distance from Sellafield; rates of decrease being in the order Zr + Nb > Ru > Cs. This can be related to the levels of the nuclides discharged, their sorption characteristics and their half lives. The pattern of seabed activity seems to have been fairly stable over the period 1978 - 1985, but there is evidence of a small northward shift. Concentrations of 137Cs and 106Ru in 1985 were considerably lower than in 1978 or 1982. This is explicable in terms of the fall in discharge levels allied, in the case of Ru, to its short half life and, for Cs, the desorption observed in laboratory experiments. Nuclide ratios in sediment samples yield apparent transit times for the transport of nuclides in the survey area of 1·7 - 3·7 years. These times are generally greater than those obtained from sediments in the more distant Solway Firth and Ravenglass Estuary. It is suggested that they reflect fairly intense bioturbation causing mixing of relatively recent effluent with that from earlier discharges. This is supported by structures observed in X-radiographs of box cores, an abundant burrowing benthos and by interpretations of nuclide profiles and radiocarbon dating of sediment cores by other workers. A lag effect, of up to two years across the survey area

  16. Modeling Spatial Distribution of a Rare and Endangered Plant Species (Brainea insignis) in Central Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, W.-C.; Lo, N.-J.; Chang, W.-I.; Huang, K.-Y.

    2012-07-01

    With an increase in the rate of species extinction, we should choose right methods that are sustainable on the basis of appropriate science and human needs to conserve ecosystems and rare species. Species distribution modeling (SDM) uses 3S technology and statistics and becomes increasingly important in ecology. Brainea insignis (cycad-fern, CF) has been categorized a rare, endangered plant species, and thus was chosen as a target for the study. Five sampling schemes were created with different combinations of CF samples collected from three sites in Huisun forest station and one site, 10 km farther north from Huisun. Four models, MAXENT, GARP, generalized linear models (GLM), and discriminant analysis (DA), were developed based on topographic variables, and were evaluated by five sampling schemes. The accuracy of MAXENT was the highest, followed by GLM and GARP, and DA was the lowest. More importantly, they can identify the potential habitat less than 10% of the study area in the first round of SDM, thereby prioritizing either the field-survey area where microclimatic, edaphic or biotic data can be collected for refining predictions of potential habitat in the later rounds of SDM or search areas for new population discovery. However, it was shown unlikely to extend spatial patterns of CFs from one area to another with a big separation or to a larger area by predictive models merely based on topographic variables. Follow-up studies will attempt to incorporate proxy indicators that can be extracted from hyperspectral images or LIDAR DEM and substitute for direct parameters to make predictive models applicable on a broader scale.

  17. Distribution and fate of perfluoroalkyl substances in Mediterranean Spanish sewage treatment plants.

    PubMed

    Campo, Julian; Masiá, Ana; Picó, Yolanda; Farré, Marinella; Barceló, Damià

    2014-02-15

    The concentrations of 21 perfluoroalkyl substances (PFASs: C4-C14, C16, C18 carboxylates, C4, C6-C8 and C10 sulfonates and C8 sulfonamide) were determined in influent, effluent and sludge from 16 different sewage treatment plants (STPs) located in the Ebro (6), Guadalquivir (5), Jucar (2) and Llobregat (3) Rivers, in two consecutive years (2010 and 2011). The analytes were extracted by solid phase extraction (SPE) and determined by Liquid Chromatography triple Quadrupole Mass Spectrometer (LC-QqQ-MS). All samples, except two sludges from Guadalquivir River STPs, were contaminated with at least one PFAS. Perfluorobutanoate (PFBA), perfluoropentanoate (PFPeA) and perfluorooctane sulfonate (L-PFOS) were the most frequently detected. The highest concentration in water was determined in 2010 in a Guadalquivir River STP (perfluorohexanoate, PFHxA: 5.60μgL(-1)) and, in 2011, in an Ebro River STP (perfluorobutane sulfonate, L-PFBS: 0.31μgL(-1)). In sludge samples, the maximum concentration in 2010 was 1.79μgg(-1)dry weight (dw) (L-PFOS, in a Llobregat River STP), and in 2011, 1.88μgg(-1)dw (PFBA, in one Guadalquivir River STP). High PFAS values in sludge could be related to positive removal efficiencies, and can be attributed to their adsorption. Distribution coefficients (Kd) were determined ranging between 0.32Lkg(-1) (perfluorohexane sulfonate, L-PFHxS) and 36.6 10(3)Lkg(-1) (PFBA). The total PFAS loads discharged into the basins showed high values for the Ebro River STPs (66.9gday(-1)) while in the others, the loads were between 3.97gday(-1), in the Jucar STPs, and 32.2gday(-1), in the Guadalquivir STPs. PMID:24342098

  18. Spatial distribution of heavy metals in surface soil, plant and mushroom beside high-frequency road

    NASA Astrophysics Data System (ADS)

    Krbić, Biljana Å.; Milovac, Snežana; Stošić, Dušan; Zorić, Miroslav; Matavulj, Milan

    2010-05-01

    One of the undesirable aspects of urbanization process is the introduction of potentially harmful pollutants into environment. Urban soils are often contaminated by metals deriving from industry, transportation and other human activities. In this study, concentration of heavy metals were investigated in roadside surface soil, linden tree bark (Tilia sp.), mushroom Schizophyllum commune and dust samples collected at different distances (0.2 - 200 m) from main high-frequency road. The samples were microwave digested in accordance to US EPA 3051 method and analyzed by flame (Cd, Cu, Co, Fe, Ni, Mn, Pb and Zn), graphite furnace (Cr) and cold vapor (Hg) atomic absorption spectrometry. The results of the analysis were used to determine major sources and distribution of heavy metals pollution. The obtained results showed significant decrease of traffic-related metals (Fe, Zn, Pb, Ni, Cu and Cd) in soil samples with increasing distance from road edge. In order to assess possible pollution, heavy metal contents in soil were compared with the National legislation and Netherlands soil quality standards. Also, elevated concentrations of traffic-related metals, especially Pb and Cr in analyzed tree bark, mushroom and dust samples, indicate the obvious roadside contamination whose primary contributors appear to be vehicular local traffic. In addition, Index of Bioaccumulation (IBA) was calculated in order to estimate plant and mushroom ability of heavy metals accumulation. Assessment of statistical differences among samples was performed by one-way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) test. Moreover, Principal Component Analysis (PCA) was performed on the heavy metals content allowed a meaningful classification of the samples according to the main sources of pollution.

  19. Rooting depth and distributions of deep-rooted plants in the 200 Area control zone of the Hanford Site

    SciTech Connect

    Klepper, E.L.; Gano, K.A.; Cadwell, L.L.

    1985-01-01

    This study was conducted to document rooting depths and distributions of deep-rooted plants common to the Hanford Site 200-Area plateau. The effort concentrated on excavating plant species suspected of having deep root systems, and species that have been reported in previous studies to contain radionuclides in above ground parts. The information obtained in this study will be useful in modeling radionuclide transport by plants and in designing covers and barriers for decommissioning low-level radioactive waste burial sites. Fourteen species including 58 individual plants were excavated to measure maximum rooting depth and root density distribution (g dry root/dm/sup 3/) through the root zone. Age and canopy volumes of shrubs were also determined. Eight of the 14 species excavated had average rooting depths of 150 cm or more. The two deepest rooted plants were antelope bitterbrush and sagebrush with average depths of 296 and 200 cm, respectively. Gray rabbitbrush had an average rooting depth of 183 cm. Summer annuals, Russian thistle and bursage, had average rooting depths of 172 and 162 cm, respectively. 7 references, 4 figures, 5 tables.

  20. [Characterization of Pb2+ adsorption on the surface of birnessite treatment with Na4P2O7 at different pH and the study on the distribution of Mn(III) in the birnessite].

    PubMed

    Zhao, Wei; Yin, Hui; Liu, Fan; Feng, Xiong-Han; Tan, Wen-Feng

    2011-08-01

    Acid birnessite was treated with Na4P2O7 at pH 2, 4, 5 respectively. After the treatments, the species and content of manganese ion in the complex solution, and the variation of average oxidation state (AOS) of Mn in birnessite, and the amount of adsorbed Pb2+ and released Mn2+, H+ during the Pb2+ adsorption were investigated. The results indicate that after acid birnessite, the AOS of Mn is 3.670 which is treated by Na4P2O7 at different pH, Mn( III) located in the layer edge and part of Mn(III) located in the interlayer are released to the solution through complexation with Na4P2O7. The content of Mn(III) in the structure of original birnessite is very low. Small amount of Mn(II), which accounts for 4.70%-7.46% in the molar percentage of total released Mn, is also released simultaneously. The AOS of Mn of birnessites after treatment increases to 3.783 (pH 2), 3.786 (pH 4), 3.824 (pH 5) respectively. While the crystal structure of birnessite does not change after treatment, the amount of Mn(III) located above or below vacant cation sites decreases, and the amount of H+ located above or below vacant cation sites goes up in the structure of birnessites. The amount of vacant cation sites responsible for Pb2+ adsorption increases, which lead to the increase of the maximum amount of adsorbed Pb2+. Additionally, the distribution of Mn(III) in the structure of acid birnessite is deduced. About one sixth of Mn(III) locates in the layer edge, and five sixths of Mn(III) locates in the interlayer and the non layer edge.

  1. Development of prediction models for radioactive caesium distribution within the 80-km radius of the Fukushima Daiichi nuclear power plant.

    PubMed

    Kinase, Sakae; Takahashi, Tomoyuki; Sato, Satoshi; Sakamoto, Ryuichi; Saito, Kimiaki

    2014-08-01

    Preliminary prediction models have been studied for the radioactive caesium distribution within the 80-km radius of the Fukushima Daiichi nuclear power plant. The models were represented by exponential functions using ecological half-life of radioactive caesium in the environment. The ecological half-lives were derived from the changes in ambient dose equivalent rates through vehicle-borne surveys. It was found that the ecological half-lives of radioactive caesium were not constant within the 80-km radius of the Fukushima Daiichi nuclear power plant. The ecological half-life of radioactive caesium in forest areas was found to be much larger than that in urban and water areas.

  2. Distribution of flavone glycoside diosmin in Hyssopus officinalis plants: changes during growth.

    PubMed

    Marin, F R; Ortuño, A; Benavente-Garcia, O; Del Rio, J A

    1998-03-01

    A study of the flavonoid composition of Hyssopus officinalis L. (Lamiaceae) plants using high-performance liquid chromatography and NMR spectroscopy revealed the presence of diosmin as the major flavone. The maximum levels of this secondary compound are located in sepals and leaves, which represent 51 and 40.5%, respectively, of the total content of diosmin in whole plant. The presence of isoferulyl D-glucose ester in this plant material was also revealed.

  3. Distribution of flavone glycoside diosmin in Hyssopus officinalis plants: changes during growth.

    PubMed

    Marin, F R; Ortuño, A; Benavente-Garcia, O; Del Rio, J A

    1998-03-01

    A study of the flavonoid composition of Hyssopus officinalis L. (Lamiaceae) plants using high-performance liquid chromatography and NMR spectroscopy revealed the presence of diosmin as the major flavone. The maximum levels of this secondary compound are located in sepals and leaves, which represent 51 and 40.5%, respectively, of the total content of diosmin in whole plant. The presence of isoferulyl D-glucose ester in this plant material was also revealed. PMID:17253233

  4. Scaling the effects of moose browsing on forage distribution, from the geometry of plant canopies to landscapes

    USGS Publications Warehouse

    De Jager, N. R.; Pastor, J.; Hodgson, A.L.

    2009-01-01

    Landscape heterogeneity influences large herbivores by altering their feeding rates, but as herbivores attempt to maximize feeding rates they also create spatial heterogeneity by altering plant growth. Herbivore feeding rates thus provide a quantitative link between the causes and consequences of spatial heterogeneity in herbivore-dominated ecosystems. The fractal geometry of plant canopies determines both the density and mass of twigs available to foraging herbivores. These properties determine a threshold distance between plants (d*) that distinguishes the mechanisms regulating herbivore intake rates. When d* is greater than the actual distance between plants (d), intake is regulated by the rate of food processing in the mouth. But when d* < d, intake is regulated by the rate at which the herbivore encounters new plants. Alterations to plant geometry due to past browsing could change the rate at which herbivores encounter and process bites of plant tissue, modify d* relative to d, and thus change intake rates and the distribution of mechanisms regulating it across landscapes. We measured changes in the geometry of aspen (Populus tremuloides) and balsam fir (Abies balsamea) saplings along gradients of moose browsing from 2001 to 2005 at Isle Royale National Park, Michigan, USA. For aspen saplings, fractal dimension of bite density, bite mass, and forage biomass responded quadratically to increasing moose browsing and were greatest at -3-4 g-g.m-2.yr"1 consumption. For balsam fir, in contrast, these same measures declined steadily with increasing moose browsing. The different responses of plant canopies to increased browsing altered d* around plants. In summer, d* > d for aspen saplings at all prior consumption levels. Food processing therefore regulated summer moose feeding rates across our landscapes. In winter, changes in bite mass due to past browsing were sufficient to cause d* < d for aspen and balsam fir. Therefore, travel velocity and food processing

  5. Variation in plant traits explains much of the global biogeographic patterns of distribution of major forest functional types

    NASA Astrophysics Data System (ADS)

    Lu, Xingjie; Wang, Ying-Ping; Reich, Peter; Wright, Ian; Dai, Yongjiu

    2015-04-01

    biogeographic pattern that evergreen needle leaf forests dominate in boreal region, evergreen broad leaf forests in tropical region, and that deciduous forests are distributed quite widely across a broad range of environmental conditions, which agrees broadly with the estimated global pattern from remote sensing. Variations and co-variations of four key plant traits can explain significant fractions of global variations of relative abundance of different forest functional types, and should be taken into account in simulating global vegetation dynamics.

  6. Dynamics of distribution and density of phreatophytes and other arid-land plant communities

    NASA Technical Reports Server (NTRS)

    Turner, R. M. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Six ERTS-1 images of the Tucson area, Arizona were analyzed to detect seasonal flushes of plant growth. Paired MSS-6 and MSS-5 bulk images were analyzed, using a ratioing technique, on the Electronic Satellite Image Analysis Console at Stanford Research Institute. Because of unique phenology, desert areas, covered only briefly by dense growths of ephemeral plants, are readily discerned. Grassland, evergreen forest, and riparian communities are also uniquely defined by their phenologies. Relatively sterile areas with little or no plant growth are easily discerned as are areas with varying degrees of plant productivity. The ratioing procedure detects plant coverage in excess of a threshold lying between 25% and 50%. The method is flexible and other coverage thresholds can be used.

  7. Heavy metal content in tea soils and their distribution in different parts of tea plants, Camellia sinensis (L). O. Kuntze.

    PubMed

    Seenivasan, Subbiah; Anderson, Todd Alan; Muraleedharan, Narayanannair

    2016-07-01

    Soils contaminated with heavy metals may pose a threat to environment and human health if metals enter the food chain over and above threshold levels. In general, there is a lack of information on the presence of heavy metals in tea [Camellia sinensis (L). O. Kuntze] plants and the soils in which they are grown. Therefore, an attempt was made to establish a database on the important heavy metals: cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb). For an initial survey on heavy metals, soil samples were collected randomly from tea-growing areas of Tamil Nadu, Kerala, and Karnataka, India. Parallel studies were conducted in the greenhouse on uptake of Pb, Cd, and Ni from soils supplemented with these metals at different concentrations. Finally, metal distribution in the tea plants under field conditions was also documented to assess the accumulation potential and critical limit of uptake by plants. PMID:27334344

  8. Contrasting nurse plants and nurse rocks: The spatial distribution of seedlings of two sub-Antarctic species

    NASA Astrophysics Data System (ADS)

    Haussmann, N. S.; McGeoch, M. A.; Boelhouwers, J. C.

    2010-05-01

    Positive plant interactions, such as those associated with nurse plants, have been suggested to dominate over negative interactions in environments with high abiotic stress. Here we demonstrate that the sub-Antarctic cushion plant species, Azorella selago (Apiaceae), positively affects the distribution of both its own seedlings and those of the perennial grass, Agrostis magellanica (Poaceae). As a result of the light weight and small size of seeds of both species, coupled with strong winds experienced in the study area, we consider it unlikely that these patterns are the result of very localized seed dispersal from the study cushions themselves. Instead, we suggest that both cushions and rocks act as seed traps, trapping seeds dispersed by wind, runoff and/or downslope sediment transport through frost creep. In addition, increased A. selago seedling numbers around cushions, but not around rocks, suggest that cushions provide a biological nurse effect, such as improving soil nutrient status or providing mychorrizae, to seedlings of their own kind.

  9. Fractionation and speciation of arsenic in three tea gardens soil profiles and distribution of As in different parts of tea plant (Camellia sinensis L.).

    PubMed

    Karak, Tanmoy; Abollino, Ornella; Bhattacharyya, Pradip; Das, Kishore K; Paul, Ranjit K

    2011-10-01

    The distribution pattern and fractionation of arsenic (As) in three soil profiles from tea (Camellia sinensis L.) gardens located in Karbi-Anglong (KA), Cachar (CA) and Karimganj (KG) districts in the state of Assam, India, were investigated depth-wise (0-10, 10-30, 30-60 and 60-100 cm). DTPA-extractable As was primarily restricted to surface horizons. Arsenic speciation study showed the presence of higher As(V) concentrations in the upper horizon and its gradual decrease with the increase in soil depths, following a decrease of Eh. As fractionation by sequential extraction in all the soil profiles showed that arsenic concentrations in the three most labile fractions (i.e., water-soluble, exchangeable and carbonate-bound fractions) were generally low. Most arsenic in soils was nominally associated with the organic and Fe-Mn oxide fractions, being extractable in oxidizing or reducing conditions. DTPA-extractable As (assumed to represent plant-available As) was found to be strongly correlated to the labile pool of As (i.e. the sum of the first three fractions). The statistical comparison of means (two-sample t-test) showed the presence of significant differences between the concentrations of As(III) and As(V) for different soil locations, depths and fractions. The risk assessment code (RAC) was found to be below the pollution level for all soils. The measurement of arsenic uptake by different parts of tea plants corroborated the hypothesis that roots act as a buffer and hold back contamination from the aerial parts. PMID:21752421

  10. Modeling the bidirectional reflectance distribution function of mixed finite plant canopies and soil

    NASA Technical Reports Server (NTRS)

    Schluessel, G.; Dickinson, R. E.; Privette, J. L.; Emery, W. J.; Kokaly, R.

    1994-01-01

    An analytical model of the bidirectional reflectance for optically semi-infinite plant canopies has been extended to describe the reflectance of finite depth canopies contributions from the underlying soil. The model depends on 10 independent parameters describing vegetation and soil optical and structural properties. The model is inverted with a nonlinear minimization routine using directional reflectance data for lawn (leaf area index (LAI) is equal to 9.9), soybeans (LAI, 2.9) and simulated reflectance data (LAI, 1.0) from a numerical bidirectional reflectance distribution function (BRDF) model (Myneni et al., 1988). While the ten-parameter model results in relatively low rms differences for the BRDF, most of the retrieved parameters exhibit poor stability. The most stable parameter was the single-scattering albedo of the vegetation. Canopy albedo could be derived with an accuracy of less than 5% relative error in the visible and less than 1% in the near-infrared. Sensitivity were performed to determine which of the 10 parameters were most important and to assess the effects of Gaussian noise on the parameter retrievals. Out of the 10 parameters, three were identified which described most of the BRDF variability. At low LAI values the most influential parameters were the single-scattering albedos (both soil and vegetation) and LAI, while at higher LAI values (greater than 2.5) these shifted to the two scattering phase function parameters for vegetation and the single-scattering albedo of the vegetation. The three-parameter model, formed by fixing the seven least significant parameters, gave higher rms values but was less sensitive to noise in the BRDF than the full ten-parameter model. A full hemispherical reflectance data set for lawn was then interpolated to yield BRDF values corresponding to advanced very high resolution radiometer (AVHRR) scan geometries collected over a period of nine days. The resulting parameters and BRDFs are similar to those for the

  11. Impacts of Photovoltaic Power Plant Sitings and Distributed Solar Panels on Meteorology and Air Quality in Central California

    NASA Astrophysics Data System (ADS)

    Bastien, L. A.; Jin, L.; Brown, N. J.

    2012-12-01

    California's electric utility companies are required to use renewable energy to produce 20% of their power by 2010 and 33% by 2020. A main source of the power will be solar energy because photovoltaic technologies have advanced so much that large scale installations are being built and will be built in the future with even greater capacity. Rather than being a large emission source, these plants affect the ambient environment through albedo changes and by emission reductions associated with not burning fossil fuels to generate the same amount of electricity. Like conventional power plants, their impact on local meteorology and air quality depends on the specific technology, ambient atmospheric conditions, and the spatial location of the plant. Also, as solar panels on commercial and residential rooftops become even more common, the effect of distributed photovoltaic panels on meteorology and air quality is likely to become significant. In this study, we use the Weather Research and Forecasting (WRF) model and the Community Multiscale Air Quality (CMAQ) model at high resolution of 4 km x 4 km over several 5-day high-ozone episodes of the summer 2000 to assess the impact of photovoltaic panels on meteorology and air quality in Central California. We investigate the effect of locating a 1.0 Giga watt solar plant in different locations and the effect of distributed rooftop photovoltaic panels in major Californian cities, with a focus on peak and 8-hour average ozone and 24-hour average PM2.5.

  12. Dispersal limitation does not control high elevational distribution of alien plant species in the southern Sierra Nevada, California

    USGS Publications Warehouse

    Rundel, Philip W.; Keeley, Jon E.

    2016-01-01

    Patterns of elevational distribution of alien plant species in the southern Sierra Nevada of California were used to test the hypothesis that alien plant species invading high elevations around the world are typically climate generalists capable of growing across a wide elevational range. The Sierra Nevada has been heavily impacted for more than a century and a half, first by heavy grazing up into high elevation meadows, followed by major logging, and finally, by impacts associated with recreational use. The comparative elevational patterns of distribution and growth form were compared for native and alien plant species in the four families (Asteraceae, Brassicaceae, Fabaceae, and Poaceae) that contribute the majority of naturalized aliens in the study area. The distribution of realized climatic niche breadth, as measured by elevational range of occurrence, was virtually identical for alien and native species, with both groups showing a roughly Gaussian distribution peaking with species whose range covers a span of 1500–1999 m. In contrast to alien species, which only rarely occurred at higher elevations, native species showed a distribution of upper elevation limits peaking at 3000–3499 m, an elevation that corresponds to the zone of upper montane and subalpine forests. Consistent with a hypothesis of abiotic limitations, only a few alien species have been ecologically successful invaders at subalpine and alpine elevations above 2500 m. The low diversity of aliens able to become established in these habitats is unlikely due to dispersal limitations, given the long history of heavy grazing pressure at high elevations across this region. Instead, this low diversity is hypothesized to be a function of life history traits and multiple abiotic stresses that include extremes of cold air and soil temperature, heavy snowfall, short growing seasons, and low resource availability. These findings have significant implications for resource managers.

  13. Exploring the spatial distribution of light interception and photosynthesis of canopies by means of a functional–structural plant model

    PubMed Central

    Sarlikioti, V.; de Visser, P. H. B.; Marcelis, L. F. M.

    2011-01-01

    Background and Aims At present most process-based models and the majority of three-dimensional models include simplifications of plant architecture that can compromise the accuracy of light interception simulations and, accordingly, canopy photosynthesis. The aim of this paper is to analyse canopy heterogeneity of an explicitly described tomato canopy in relation to temporal dynamics of horizontal and vertical light distribution and photosynthesis under direct- and diffuse-light conditions. Methods Detailed measurements of canopy architecture, light interception and leaf photosynthesis were carried out on a tomato crop. These data were used for the development and calibration of a functional–structural tomato model. The model consisted of an architectural static virtual plant coupled with a nested radiosity model for light calculations and a leaf photosynthesis module. Different scenarios of horizontal and vertical distribution of light interception, incident light and photosynthesis were investigated under diffuse and direct light conditions. Key Results Simulated light interception showed a good correspondence to the measured values. Explicitly described leaf angles resulted in higher light interception in the middle of the plant canopy compared with fixed and ellipsoidal leaf-angle distribution models, although the total light interception remained the same. The fraction of light intercepted at a north–south orientation of rows differed from east–west orientation by 10 % on winter and 23 % on summer days. The horizontal distribution of photosynthesis differed significantly between the top, middle and lower canopy layer. Taking into account the vertical variation of leaf photosynthetic parameters in the canopy, led to approx. 8 % increase on simulated canopy photosynthesis. Conclusions Leaf angles of heterogeneous canopies should be explicitly described as they have a big impact both on light distribution and photosynthesis. Especially, the vertical

  14. A rule-based model for mapping potential exotic plant distribution

    USGS Publications Warehouse

    Despain, D.G.; Weaver, T.; Aspinall, R.J.

    2001-01-01

    Wildland managers need a method to predict which portions of the lands under their stewardship are susceptible to invasion by exotic plants. We combined a database listing exotic plant species known to occur in major environmental types (habitat types) throughout the northern Rocky Mountains with a digital vegetation map of environmental types for a major national park in the region (Yellowstone National Park) to produce maps of areas potentially threatened by major exotic species. Such maps should be helpful to managers concerned with monitoring and controlling exotic plants.

  15. Computer program for afterheat temperature distribution for mobile nuclear power plant

    NASA Technical Reports Server (NTRS)

    Parker, W. G.; Vanbibber, L. E.

    1972-01-01

    ESATA computer program was developed to analyze thermal safety aspects of post-impacted mobile nuclear power plants. Program is written in FORTRAN 4 and designed for IBM 7094/7044 direct coupled system.

  16. Pseudomonas syringae lytic transglycosylases coregulated with the type III secretion system contribute to the translocation of effector proteins into plant cells.

    PubMed

    Oh, Hye-Sook; Kvitko, Brian H; Morello, Joanne E; Collmer, Alan

    2007-11-01

    Pseudomonas syringae translocates virulence effector proteins into plant cells via a type III secretion system (T3SS) encoded by hrp (for hypersensitive response and pathogenicity) genes. Three genes coregulated with the Hrp T3SS system in P. syringae pv. tomato DC3000 have predicted lytic transglycosylase domains: PSPTO1378 (here designated hrpH), PSPTO2678 (hopP1), and PSPTO852 (hopAJ1). hrpH is located between hrpR and avrE1 in the Hrp pathogenicity island and is carried in the functional cluster of P. syringae pv. syringae 61 hrp genes cloned in cosmid pHIR11. Strong expression of DC3000 hrpH in Escherichia coli inhibits bacterial growth unless the predicted catalytic glutamate at position 148 is mutated. Translocation tests involving C-terminal fusions with a Cya (Bordetella pertussis adenylate cyclase) reporter indicate that HrpH and HopP1, but not HopAJ1, are T3SS substrates. Pseudomonas fluorescens carrying a pHIR11 derivative lacking hrpH is poorly able to translocate effector HopA1, and this deficiency can be restored by HopP1 and HopAJ1, but not by HrpH(E148A) or HrpH(1-241). DC3000 mutants lacking hrpH or hrpH, hopP1, and hopAJ1 combined are variously reduced in effector translocation, elicitation of the hypersensitive response, and virulence. However, the mutants are not reduced in secretion of T3SS substrates in culture. When produced in wild-type DC3000, the HrpH(E148A) and HrpH(1-241) variants have a dominant-negative effect on the ability of DC3000 to elicit the hypersensitive response in nonhost tobacco and to grow and cause disease in host tomato. The three Hrp-associated lytic transglycosylases in DC3000 appear to have overlapping functions in contributing to T3SS functions during infection.

  17. Brominated flame retardants in the surrounding soil of two manufacturing plants in China: Occurrence, composition profiles and spatial distribution.

    PubMed

    Li, Wen-Long; Liu, Li-Yan; Zhang, Zi-Feng; Song, Wei-Wei; Huo, Chun-Yan; Qiao, Li-Na; Ma, Wan-Li; Li, Yi-Fan

    2016-06-01

    Surface soil samples were collected surrounding two brominated flame retardants (BFRs) manufacturing plants in China in August 2014 and analyzed for 23 polybrominated diphenyl ethers (PBDEs) and 8 novel brominated flame retardants (NBFRs). BDE209 and decabromodiphenylethane (DBDPE) were the predominant compounds in soil with the median levels of 1600 and 560 ng/g dw, respectively. The PBDEs profiles in soil samples were consistent with that of commercial product (comDecaBDE). The percentage contributions to total PBDEs decreased from higher to lower brominated homologues. Lower concentrations of NBFRs (excluding DBDPE) were detected in soil surrounding the two plants, suggesting they are byproducts or degradation products of the manufacturing activities. The concentrations of most BFRs dropped exponentially within 3-5 km of the manufacturing plants, suggesting recent deposition of these compounds to the soil. Directional distribution indicated that PBDEs and DBDPE concentrations were highest in the north direction of Plants 1. Three-day air parcel forward trajectories confirmed that the air parcel was responsible for the higher concentration of BFRs in the soil of north direction of the plant.

  18. Effect of different plant species on nutrient removal and rhizospheric microorganisms distribution in horizontal-flow constructed wetlands.

    PubMed

    Meng, Panpan; Hu, Wenrong; Pei, Haiyan; Hou, Qingjie; Ji, Yan

    2014-01-01

    Three macrophyte species, Phragmites australis, Arundo donax L., and Typha latifolia L. have been separately grown in a horizontal-flow (HF) constructed wetland (CW) fed with domestic wastewater to investigate effects of plant species on nutrient removal and rhizospheric microorganisms. All the three mesocosms have been in operation for eight months under the loading rates of 1.14 g Nm(-2) d(-1) and 0.014gP m(-2) d(-1). Appropriately 34-43% phosphorus (P) was removed in HF CWs, and no distinct difference was found among the plants. In the growing season, A. donax L. removed 31.19 gm(-2) of nitrogen (N), followed by P. australis (29.96 g m(-2)), both of which were significantly higher than T. latifolia L. (7.21 g m(-2). Depending on the species, plants absorbed 1.73-7.15% of the overall N, and 0.06-0.56% of the P input. At least 10 common dominant microorganisms were found in the rhizosphere of all the three plants, and 6 of the 10 kinds of bacteria had close relationship with denitrifying bacteria, implying that denitrifiers were dominant microorganism distributed in rhizosphere of wetland plants.

  19. Brominated flame retardants in the surrounding soil of two manufacturing plants in China: Occurrence, composition profiles and spatial distribution.

    PubMed

    Li, Wen-Long; Liu, Li-Yan; Zhang, Zi-Feng; Song, Wei-Wei; Huo, Chun-Yan; Qiao, Li-Na; Ma, Wan-Li; Li, Yi-Fan

    2016-06-01

    Surface soil samples were collected surrounding two brominated flame retardants (BFRs) manufacturing plants in China in August 2014 and analyzed for 23 polybrominated diphenyl ethers (PBDEs) and 8 novel brominated flame retardants (NBFRs). BDE209 and decabromodiphenylethane (DBDPE) were the predominant compounds in soil with the median levels of 1600 and 560 ng/g dw, respectively. The PBDEs profiles in soil samples were consistent with that of commercial product (comDecaBDE). The percentage contributions to total PBDEs decreased from higher to lower brominated homologues. Lower concentrations of NBFRs (excluding DBDPE) were detected in soil surrounding the two plants, suggesting they are byproducts or degradation products of the manufacturing activities. The concentrations of most BFRs dropped exponentially within 3-5 km of the manufacturing plants, suggesting recent deposition of these compounds to the soil. Directional distribution indicated that PBDEs and DBDPE concentrations were highest in the north direction of Plants 1. Three-day air parcel forward trajectories confirmed that the air parcel was responsible for the higher concentration of BFRs in the soil of north direction of the plant. PMID:26874313

  20. Cell layer-specific distribution of transiently expressed barley ESCRT-III component HvVPS60 in developing barley endosperm.

    PubMed

    Hilscher, Julia; Kapusi, Eszter; Stoger, Eva; Ibl, Verena

    2016-01-01

    The significance of the endosomal sorting complexes required for transport (ESCRT)-III in cereal endosperm has been shown by the identification of the recessive mutant supernumerary aleurone layer1 (SAL1) in maize. ESCRT-III is indispensable in the final membrane fission step during biogenesis of multivesicular bodies (MVBs), responsible for protein sorting to vacuoles and to the cell surface. Here, we annotated barley ESCRT-III members in the (model) crop Hordeum vulgare and show that all identified members are expressed in developing barley endosperm. We used fluorescently tagged core ESCRT-III members HvSNF7a/CHMP4 and HvVPS24/CHMP3 and the associated ESCRT-III component HvVPS60a/CHMP5 for transient localization studies in barley endosperm. In vivo confocal microscopic analyses show that the localization of recombinantly expressed HvSNF7a, HvVPS24 and HvVPS60a differs within barley endosperm. Whereas HvSNF7a induces large agglomerations, HvVPS24 shows mainly cytosolic localization in aleurone and subaleurone. In contrast, HvVPS60a localizes strongly at the plasma membrane in aleurone. In subaleurone, HvVPS60a was found to a lesser extent at the plasma membrane and at vacuolar membranes. These results indicate that the steady-state association of ESCRT-III may be influenced by cell layer-specific protein deposition or trafficking and remodelling of the endomembrane system in endosperm. We show that sorting of an artificially mono-ubiquitinated Arabidopsis plasma membrane protein is inhibited by HvVPS60a in aleurone. The involvement of HvVPS60a in different cell layer-specific trafficking pathways, reflected by localization of HvVPS60a at the plasma membrane in aleurone and at the PSV membrane in subaleurone, is discussed.

  1. Welding III.

    ERIC Educational Resources Information Center

    Allegheny County Community Coll., Pittsburgh, PA.

    Instructional objectives and performance requirements are outlined in this course guide for Welding III, an advanced course in arc welding offered at the Community College of Allegheny County to provide students with the proficiency necessary for industrial certification. The course objectives, which are outlined first, specify that students will…

  2. Arctic plant origins and early formation of circumarctic distributions: a case study of the mountain sorrel, Oxyria digyna.

    PubMed

    Wang, Qian; Liu, Jianquan; Allen, Geraldine A; Ma, Yazhen; Yue, Wei; Marr, Kendrick L; Abbott, Richard J

    2016-01-01

    Many plant species comprising the present-day Arctic flora are thought to have originated in the high mountains of North America and Eurasia, migrated northwards as global temperatures fell during the late Tertiary period, and thereafter attained a circumarctic distribution. However, supporting evidence for this hypothesis that provides a temporal framework for the origin, spread and initial attainment of a circumarctic distribution by an arctic plant is currently lacking. Here we examined the origin and initial formation of a circumarctic distribution of the arctic mountain sorrel (Oxyria digyna) by conducting a phylogeographic analysis of plastid and nuclear gene DNA variation. We provide evidence for an origin of this species in the Qinghai-Tibet Plateau of southwestern China, followed by migration into Russia c. 11 million yr ago (Ma), eastwards into North America by c. 4 Ma, and westwards into Western Europe by c. 1.96 Ma. Thereafter, the species attained a circumarctic distribution by colonizing Greenland from both sides of the Atlantic Ocean. Following the arrival of the species in North America and Europe, population sizes appear to have increased and then stabilized there over the last 1 million yr. However, in Greenland a marked reduction followed by an expansion in population size is indicated to have occurred during the Pleistocene. PMID:26197783

  3. Arctic plant origins and early formation of circumarctic distributions: a case study of the mountain sorrel, Oxyria digyna.

    PubMed

    Wang, Qian; Liu, Jianquan; Allen, Geraldine A; Ma, Yazhen; Yue, Wei; Marr, Kendrick L; Abbott, Richard J

    2016-01-01

    Many plant species comprising the present-day Arctic flora are thought to have originated in the high mountains of North America and Eurasia, migrated northwards as global temperatures fell during the late Tertiary period, and thereafter attained a circumarctic distribution. However, supporting evidence for this hypothesis that provides a temporal framework for the origin, spread and initial attainment of a circumarctic distribution by an arctic plant is currently lacking. Here we examined the origin and initial formation of a circumarctic distribution of the arctic mountain sorrel (Oxyria digyna) by conducting a phylogeographic analysis of plastid and nuclear gene DNA variation. We provide evidence for an origin of this species in the Qinghai-Tibet Plateau of southwestern China, followed by migration into Russia c. 11 million yr ago (Ma), eastwards into North America by c. 4 Ma, and westwards into Western Europe by c. 1.96 Ma. Thereafter, the species attained a circumarctic distribution by colonizing Greenland from both sides of the Atlantic Ocean. Following the arrival of the species in North America and Europe, population sizes appear to have increased and then stabilized there over the last 1 million yr. However, in Greenland a marked reduction followed by an expansion in population size is indicated to have occurred during the Pleistocene.

  4. Patchy distributions of competitors affect the growth of a clonal plant when the competitor density is high.

    PubMed

    Xue, Wei; Huang, Lin; Dong, Bi-Cheng; Zhang, Ming-Xiang; Yu, Fei-Hai

    2013-01-01

    Environments are patchy in not only abiotic factors but also biotic ones. Many studies have examined effects of spatial heterogeneity in abiotic factors such as light, water and nutrients on the growth of clonal plants, but few have tested those in biotic factors. We conducted a greenhouse experiment to examine how patchy distributions of competitors affect the growth of a rhizomatous wetland plant Bolboschoenus planiculmis and whether such effects depend on the density of the competitors. We grew one ramet of B. planiculmis in the center of each of the experimental boxes without competitors (Schoenoplectus triqueter), with a homogeneous distribution of the competitors of low or high density, and with a patchy distribution of the competitors of low or high density. The presence of competitors markedly decreased the growth (biomass, number of ramets, number of tubers and rhizome length) of the B. planiculmis clones. When the density of the competitors was low, the growth of B. planiculmis did not differ significantly between the competitor patches and competitor-free patches. However, when the density of the competitors was high, the growth of B. planiculmis was significantly higher in the competitor-free patches than in the competitor patches. Therefore, B. planiculmis can respond to patchy distributions of competitors by placing more ramets in competition-free patches when the density of competitors is high, but cannot do so when the density of competitors is low.

  5. Distribution of local 137Cs anomalies on the seafloor near the Fukushima Dai-ichi Nuclear Power Plant.

    PubMed

    Thornton, Blair; Ohnishi, Seiki; Ura, Tamaki; Odano, Naoteru; Sasaki, Shun; Fujita, Tsuneo; Watanabe, Tomowo; Nakata, Kaoru; Ono, Tsuneo; Ambe, Daisuke

    2013-09-15

    An estimated 3.5±0.7×10(15) Bq of (137)Cs is thought to have been discharged into the ocean following the melt down at Fukushima Dai-ichi Nuclear Power Plant (F1NPP). While efforts have been made to monitor seafloor radiation levels, the sampling techniques used cannot capture the continuous distribution of radionuclides. In this work, we apply in situ measurement techniques using a towed gamma ray spectrometer to map the continuous distribution of (137)Cs on the seafloor within 20 km of the F1NPP. The results reveal the existence of local (137)Cs anomalies, with levels of (137)Cs an order of magnitude higher than the surrounding seafloors. The sizes of the anomalies mapped in this work range from a few meters to a few hundreds of meters in length, and it is demonstrated that the distribution of these anomalies is strongly influenced by meter scale features of the terrain.

  6. Remote-Sensed Monitoring of Dominant Plant Species Distribution and Dynamics at Jiuduansha Wetland in Shanghai, China

    DOE PAGES

    Lin, Wenpeng; Chen, Guangsheng; Guo, Pupu; Zhu, Wenquan; Zhang, Donghai

    2015-08-11

    Spartina alterniflora is one of the most hazardous invasive plant species in China. Monitoring the changes in dominant plant species can help identify the invasion mechanisms of S. alterniflora, thereby providing scientific guidelines on managing or controlling the spreading of this invasive species at Jiuduansha Wetland in Shanghai, China. However, because of the complex terrain and the inaccessibility of tidal wetlands, it is very difficult to conduct field experiments on a large scale in this wetland. Hence, remote sensing plays an important role in monitoring the dynamics of plant species and its distribution on both spatial and temporal scales. Inmore » this paper, based on multi-spectral and high resolution (<10 m) remote sensing images and field observational data, we analyzed spectral characteristics of four dominant plant species at different green-up phenophases. Based on the difference in spectral characteristics, a decision tree classification was built for identifying the distribution of these plant species. The results indicated that the overall classification accuracy for plant species was 87.17%, and the Kappa Coefficient was 0.81, implying that our classification method could effectively identify the four plant species. We found that the area of Phragmites australi showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 33.77% and 31.92%, respectively. The area of Scirpus mariqueter displayed an increasing trend from 1997 to 2004 (12.16% per year) and a decreasing trend from 2004 to 2012 (-7.05% per year). S. alterniflora has the biggest area (3302.20 ha) as compared to other species, accounting for 51% of total vegetated area at the study region in 2012. It showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 130.63% and 28.11%, respectively. As a result, the native species P. australi was surrounded and the habitats of S. mariqueter were occupied by S

  7. Remote-Sensed Monitoring of Dominant Plant Species Distribution and Dynamics at Jiuduansha Wetland in Shanghai, China

    SciTech Connect

    Lin, Wenpeng; Chen, Guangsheng; Guo, Pupu; Zhu, Wenquan; Zhang, Donghai

    2015-08-11

    Spartina alterniflora is one of the most hazardous invasive plant species in China. Monitoring the changes in dominant plant species can help identify the invasion mechanisms of S. alterniflora, thereby providing scientific guidelines on managing or controlling the spreading of this invasive species at Jiuduansha Wetland in Shanghai, China. However, because of the complex terrain and the inaccessibility of tidal wetlands, it is very difficult to conduct field experiments on a large scale in this wetland. Hence, remote sensing plays an important role in monitoring the dynamics of plant species and its distribution on both spatial and temporal scales. In this paper, based on multi-spectral and high resolution (<10 m) remote sensing images and field observational data, we analyzed spectral characteristics of four dominant plant species at different green-up phenophases. Based on the difference in spectral characteristics, a decision tree classification was built for identifying the distribution of these plant species. The results indicated that the overall classification accuracy for plant species was 87.17%, and the Kappa Coefficient was 0.81, implying that our classification method could effectively identify the four plant species. We found that the area of Phragmites australi showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 33.77% and 31.92%, respectively. The area of Scirpus mariqueter displayed an increasing trend from 1997 to 2004 (12.16% per year) and a decreasing trend from 2004 to 2012 (-7.05% per year). S. alterniflora has the biggest area (3302.20 ha) as compared to other species, accounting for 51% of total vegetated area at the study region in 2012. It showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 130.63% and 28.11%, respectively. As a result, the native species P. australi was surrounded and the habitats of S. mariqueter were occupied by S

  8. Tree cover at fine and coarse spatial grains interacts with shade tolerance to shape plant species distributions across the Alps

    PubMed Central

    Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain; Aeschimann, David; Dullinger, Stefan; Gégout, Jean-Claude; Guisan, Antoine; Pauli, Harald; Renaud, Julien; Theurillat, Jean-Paul; Thuiller, Wilfried; Van Es, Jérémie; Vittoz, Pascal; Willner, Wolfgang; Wohlgemuth, Thomas; Zimmermann, Niklaus E.; Svenning, Jens-Christian

    2015-01-01

    The role of competition for light among plants has long been recognised at local scales, but its importance for plant species distributions at larger spatial scales has generally been ignored. Tree cover modifies the local abiotic conditions below the canopy, notably by reducing light availability, and thus, also the performance of species that are not adapted to low-light conditions. However, this local effect may propagate to coarser spatial grains, by affecting colonisation probabilities and local extinction risks of herbs and shrubs. To assess the effect of tree cover at both the plot- and landscape-grain sizes (approximately 10-m and 1-km), we fit Generalised Linear Models (GLMs) for the plot-level distributions of 960 species of herbs and shrubs using 6,935 vegetation plots across the European Alps. We ran four models with different combinations of variables (climate, soil and tree cover) at both spatial grains for each species. We used partial regressions to evaluate the independent effects of plot- and landscape-grain tree cover on plot-level plant communities. Finally, the effects on species-specific elevational range limits were assessed by simulating a removal experiment comparing the species distributions under high and low tree cover. Accounting for tree cover improved the model performance, with the probability of the presence of shade-tolerant species increasing with increasing tree cover, whereas shade-intolerant species showed the opposite pattern. The tree cover effect occurred consistently at both the plot and landscape spatial grains, albeit most strongly at the former. Importantly, tree cover at the two grain sizes had partially independent effects on plot-level plant communities. With high tree cover, shade-intolerant species exhibited narrower elevational ranges than with low tree cover whereas shade-tolerant species showed wider elevational ranges at both limits. These findings suggest that forecasts of climate-related range shifts for herb

  9. Why are most aquatic plants widely distributed? Dispersal, clonal growth and small-scale heterogeneity in a stressful environment

    NASA Astrophysics Data System (ADS)

    Santamaría, Luis

    2002-06-01

    Non-marine aquatic vascular plants generally show broad distributional ranges. Climatic factors seem to have limited effects on their distributions, besides the determination of major disjunctions (tropical-temperate-subarctic). Dispersal should have been frequent enough to assure the quick colonisation of extensive areas following glacial retreat, but dispersal limitation is still apparent in areas separated by geographic barriers. Aquatic vascular plants also show limited taxonomic differentiation and low within-species genetic variation. Variation within populations is particularly low, but variation among populations seems to be relatively high, mainly due to the persistence of long-lived clones. Ecotypic differentiation is often related to factors that constrain clonal reproduction (salinity and ephemeral inundation). Inland aquatic habitats are heterogeneous environments, but this heterogeneity largely occurs at relatively small scales (within waterbodies and among neighbouring ones). They also represent a stressful environment for plants, characterised by low carbon availability, shaded conditions, sediment anoxia, mechanical damage by currents and waves, significant restrictions to sexual reproduction, and sometimes also osmotic stress and limited nutrient supply. I propose that the generality of broad distributions and low differentiation among the inland aquatic flora is best explained by a combination of: (1) selection for stress-tolerant taxa with broad tolerance ranges. (2) The selective advantages provided by clonal growth and multiplication, which increases plant tolerance to stress, genet survivorship and population viability. (3) Long-distance dispersal of sexual propagules and high local dispersal of asexual clones. (4) The generality of broad plastic responses, promoted by the combination of clonal growth, high local dispersal, small-scale spatial heterogeneity and temporal variability.

  10. Low persistence of a monocarpic invasive plant in historical sites biases our perception of its actual distribution

    PubMed Central

    Pergl, Jan; Pyšek, Petr; Perglová, Irena; Jarošík, Vojtěch; Procheş, Şerban

    2012-01-01

    Aim As accurate and up-to-date distribution data for plant species are rarely available, cumulative records over long periods of time are frequently used for mapping distributions, without taking into account that species do not persist in their historical localities forever. However, persistence is highly relevant in changing modern landscapes, especially for invasive species that dynamically spread in unstable human-made habitats. We studied how an invasive species, Heracleum mantegazzianum, persists at sites once colonized and how its ability to persist affects its distribution. Location The Czech Republic. Methods We visited 521 localities of H. mantegazzianum occurrence reported in the literature and herbaria to determine whether the species still occurs at these sites. By using G-tests and classification trees, we explored the roles of various factors affecting its persistence at a site. Results Of the total number of 521 historical sites at which the species has occurred since the end of the 19th century, it persists at only 124 (23.8%). The persistence rate differs with respect to habitat type and is highest in meadows and forest margins. Analysis using classification trees indicated that the factors that best explain persistence are: type of habitat (with meadow and forest margins over-represented); urbanity (with a higher persistence outside urban areas); proximity to the place of the species’ introduction into the country; metapopulation connectivity; and distance to the nearest neighbouring population. Main conclusions The use of cumulative historical records as a measure of species distribution, which is common in invasion literature, can seriously overestimate the actual distribution of alien plant species with low persistence. In the case of alien species such as H. mantegazzanium, which is non-clonal and reproduces only by seed, estimates of distribution and spread based on historical data are informative about potentially suitable habitat but may

  11. Mass and number size distributions of emitted particulates at five important operation units in a hazardous industrial waste incineration plant.

    PubMed

    Lin, Chi-Chi; Huang, Hsiao-Lin; Hsiao, Wen-Yuan

    2016-01-01

    Past studies indicated particulates generated by waste incineration contain various hazardous compounds. The aerosol characteristics are very important for particulate hazard control and workers' protection. This study explores the detailed characteristics of emitted particulates from each important operation unit in a rotary kiln-based hazardous industrial waste incineration plant. A dust size analyzer (Grimm 1.109) and a scanning mobility particle sizer (SMPS) were used to measure the aerosol mass concentration, mass size distribution, and number size distribution at five operation units (S1-S5) during periods of normal operation, furnace shutdown, and annual maintenance. The place with the highest measured PM10 concentration was located at the area of fly ash discharge from air pollution control equipment (S5) during the period of normal operation. Fine particles (PM2.5) constituted the majority of the emitted particles from the incineration plant. The mass size distributions (elucidated) made it clear that the size of aerosols caused by the increased particulate mass, resulting from work activities, were mostly greater than 1.5 μm. Whereas the number size distributions showed that the major diameters of particulates that caused the increase of particulate number concentrations, from work activities, were distributed in the sub micrometer range. The process of discharging fly ash from air pollution control equipment can significantly increase the emission of nanoparticles. The mass concentrations and size distributions of emitted particulates were different at each operation unit. This information is valuable for managers to take appropriate strategy to reduce the particulate emission and associated worker exposure.

  12. Mass and number size distributions of emitted particulates at five important operation units in a hazardous industrial waste incineration plant.

    PubMed

    Lin, Chi-Chi; Huang, Hsiao-Lin; Hsiao, Wen-Yuan

    2016-01-01

    Past studies indicated particulates generated by waste incineration contain various hazardous compounds. The aerosol characteristics are very important for particulate hazard control and workers' protection. This study explores the detailed characteristics of emitted particulates from each important operation unit in a rotary kiln-based hazardous industrial waste incineration plant. A dust size analyzer (Grimm 1.109) and a scanning mobility particle sizer (SMPS) were used to measure the aerosol mass concentration, mass size distribution, and number size distribution at five operation units (S1-S5) during periods of normal operation, furnace shutdown, and annual maintenance. The place with the highest measured PM10 concentration was located at the area of fly ash discharge from air pollution control equipment (S5) during the period of normal operation. Fine particles (PM2.5) constituted the majority of the emitted particles from the incineration plant. The mass size distributions (elucidated) made it clear that the size of aerosols caused by the increased particulate mass, resulting from work activities, were mostly greater than 1.5 μm. Whereas the number size distributions showed that the major diameters of particulates that caused the increase of particulate number concentrations, from work activities, were distributed in the sub micrometer range. The process of discharging fly ash from air pollution control equipment can significantly increase the emission of nanoparticles. The mass concentrations and size distributions of emitted particulates were different at each operation unit. This information is valuable for managers to take appropriate strategy to reduce the particulate emission and associated worker exposure. PMID:26771771

  13. Alkane distribution and carbon isotope composition in fossil leaves: An interpretation of plant physiology in the geologic past

    NASA Astrophysics Data System (ADS)

    Graham, H. V.; Freeman, K. H.

    2014-12-01

    The relative chain-length distribution and carbon-isotope composition of n-alkanes extracted from sedimentary rocks are important geochemical tools for investigating past terrestrial ecosystems. Alkanes preserved in ancient sediments are assumed to be contemporaneous, derived from the same ecosystem, and integrated from the biomass present on the landscape at the time of deposition. Further, there is an underlying assumption that ancient plants exhibited the same metabolic and physiological responses to climate conditions that are observed for modern plants. Interpretations of alkane abundances and isotopic signatures are complicated by the strong influence of phylogenetic affiliation and ecological factors, such as canopy structure. A better understanding of how ecosystem and taxa influence alkane properties, including homologue abundance patterns and leaf-lipid carbon isotope fractionation would help strengthen paleoecological interpretations based on these widely employed plant biomarkers. In this study, we analyze the alkane chain-length distribution and carbon-isotope composition of phytoleim and alkanes (d13Cleaf and d13Clipid) extracted from a selection of Cretaceous and Paleocene fossil leaves from the Guaduas and Cerrejon Formations of Colombia. These data were compared with data for the same families in a modern analogue biome. Photosynthetic and biosynthetic fractionation (∆leaf and elipid) values determined from the fossil material indicate carbon metabolism patterns were similar to modern plants. Fossil data were incorporated in a biomass-weighted mixing model to represent the expected lipid complement of sediment arising from this ecosystem and compared with alkane measurements from the rock matrix. Modeled and observed isotopic and abundance patterns match well for alkane homologs most abundant in plants (i.e., n-C27 to n-C33). The model illustrates the importance of understanding biases in litter flux and taphonomic pressures inherent in the

  14. Climatic variability and plant food distribution in Pleistocene Europe: Implications for Neanderthal diet and subsistence

    NASA Astrophysics Data System (ADS)

    Hardy, Bruce L.

    2010-03-01

    Contrary to their cold-adapted image, Neanderthals inhabited Pleistocene Europe during a time of great climatic fluctuation with temperatures ranging from as warm as present-day during the last interglacial to as cold as those of the last glacial maximum. Cold-adapted Neanderthals are similarly most often associated with the exploitation of large mammals who are themselves cold-adapted (mammoth, bison, reindeer, etc.). Cold, high-latitude environments are typically seen as lacking in plants generally and in plant foods in particular. Plant foods are therefore usually ignored and Neanderthals are increasingly being viewed as top carnivores who derived the vast majority of their diet from meat. Support for this hypothesis comes largely from stable isotope analysis which tracks only the protein portion of the diet. Diets high in lean meat largely fulfill micronutrient needs but can pose a problem at the macronutrient level. Lean meat can compose no more than 35% of dietary energy before a protein ceiling is reached. Exceeding the protein ceiling can have detrimental physiological effects on the individual. Neanderthals would have needed energy from alternative sources, particularly when animals are fat-depleted and lean meat intake is high. Underground storage organs (USOs) of plants offer one such source, concentrating carbohydrates and energy. USOs could also provide an important seasonal energy source since they are at their maximum energy storage in late fall/winter. Although Paleolithic sites are increasingly yielding plant remains, their presence is rare and they are often given only passing mention in Neanderthal dietary reconstructions. The complexity and number of potential wild plant foods, however, defies easy discussion. Native European wild edible plants with starchy USOs would have been potentially available throughout the Neanderthal range, even during the coldest periods of the Late Pleistocene.

  15. TRAMIL Ethnopharmacological Survey: Knowledge Distribution of Medicinal Plant Use in the Southeast Region of Puerto Rico

    PubMed Central

    ALVARADO-GUZMÁN, JOSÉ A.; GAVILLÁN-SUÁREZ, JANNETTE; GERMOSÉN-ROBINEAU, LIONEL

    2014-01-01

    Background TRAMIL network aims to understand, validate and expand health practices based on the use of medicinal plants in the Caribbean, a “biodiversity hotspot” due to high species endemism, intense development pressure and habitat loss. Objectives The purpose of this study was to document both the medicinal plants that are frequently used to treat health conditions prevalent in the southeastern region of the archipelago of Puerto Rico and the trends in their use among the study population. Methods An ethnopharmacological survey was conducted in the study region. The results were analyzed using univariate and multivariate statistical analyses. Results Overall, 118 medicinal plants were recorded as being used to treat depression, nervousness, chronic sinusitis, gastritis, gastroesophageal reflux disease, allergic rhinitis, rhinofaryngitis, asthma, arthritis and migraine. The plant species with significant use were Citrus aurantium L., Citrus aurantifolia (Christm.) Swingle, Pluchea carolinensis (Jacq.) G. Don in Sweet, and Mentha piperita L. The use of medicinal plants is more frequent among single women with a high educational level, a trend similar to the use of CAM in the US. Conclusion Ethnopharmacological knowledge and the use of medicinal plants is decreasing in the study region due to an increase in the use of conventional medical care and to self-medication with over-the-counter pharmaceutical products. Four botanical species with significant uses that were not previously recorded in the Caribbean Herbal Pharmacopoeia have been identified. This report will be followed by the scientific validation and toxicity studies of these plant species and the TRADIF activities in the study region. PMID:19999241

  16. Potential link between plant and fungal distributions in a dipterocarp rainforest: community and phylogenetic structure of tropical ectomycorrhizal fungi across a plant and soil ecotone.

    PubMed

    Peay, Kabir G; Kennedy, Peter G; Davies, Stuart J; Tan, Sylvester; Bruns, Thomas D

    2010-01-01

    *Relatively little is known about diversity or structure of tropical ectomycorrhizal communities or their roles in tropical ecosystem dynamics. In this study, we present one of the largest molecular studies to date of an ectomycorrhizal community in lowland dipterocarp rainforest. *We sampled roots from two 0.4 ha sites located across an ecotone within a 52 ha forest dynamics plot. Our plots contained > 500 tree species and > 40 species of ectomycorrhizal host plants. Fungi were identified by sequencing ribosomal RNA genes. *The community was dominated by the Russulales (30 species), Boletales (17), Agaricales (18), Thelephorales (13) and Cantharellales (12). Total species richness appeared comparable to molecular studies of temperate forests. Community structure changed across the ecotone, although it was not possible to separate the role of environmental factors vs host plant preferences. Phylogenetic analyses were consistent with a model of community assembly where habitat associations are influenced by evolutionary conservatism of functional traits within ectomycorrhizal lineages. *Because changes in the ectomycorrhizal fungal community parallel those of the tree community at this site, this study demonstrates the potential link between the distribution of tropical tree diversity and the distribution of tropical ectomycorrhizal diversity in relation to local-scale edaphic variation.

  17. Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation.

    PubMed

    Han, Shuping; Naito, Wataru; Masunaga, Shigeki

    2016-01-01

    To assess the effects of Fe(III) and anthropogenic ligands on the bioavailability of Ni, Cu, Zn, and Pb, concentrations of bioavailable metals were measured by the DGT (diffusive gradients in thin films) method in some urban rivers, and were compared with concentrations calculated by a chemical equilibrium model (WHAM 7.0). Assuming that dissolved Fe(III) (<0.45 μm membrane filtered) was in equilibrium with colloidal iron oxide, the WHAM 7.0 model estimated that bioavailable concentrations of Ni, Cu, and Zn were slightly higher than the corresponding values estimated assuming that dissolved Fe(III) was absent. In contrast, lower levels of free Pb were predicted by the WHAM 7.0 model when dissolved Fe(III) was included. Estimates showed that most of the dissolved Pb was present as colloidal iron-Pb complex. Ethylene-diamine-tetra-acetic acid (EDTA) concentrations at sampling sites were predicted from the relationship between EDTA and the calculated bioavailable concentration of Zn. When both colloidal iron and predicted EDTA concentrations were included in the WHAM 7.0 calculations, dissolved metals showed a strong tendency to form EDTA complexes, in the order Ni > Cu > Zn > Pb. With the inclusion of EDTA, bioavailable concentrations of Ni, Cu, and Zn predicted by WHAM 7.0 were different from those predicted considering only humic substances and colloidal iron. PMID:27533864

  18. The movement and distribution of Helicoverpa armigera (Hübner) larvae on pea plants is affected by egg placement and flowering.

    PubMed

    Perkins, L E; Cribb, B W; Hanan, J; Zalucki, M P

    2010-10-01

    The distribution and movement of 1st instar Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae on whole garden pea (Pisum sativum L.) plants were determined in glasshouse trials. This economically-important herbivore attacks a wide variety of agricultural, horticultural and indigenous plants. To investigate the mechanisms underlying larval intra-plant movement, we used early-flowering and wild-type plant genotypes and placed eggs at different vertical heights within the plants, one egg per plant. Leaf water and nitrogen content and cuticle hardness were measured at the different plant heights. Of 92 individual larvae, 41% did not move from the node of eclosion, 49% moved upwards and 10% moved downwards with the distance moved being between zero and ten plant nodes. Larvae from eggs placed on the lower third of the plant left the natal leaf more often and moved further than larvae from eggs placed in the middle or upper thirds. The low nutritive value of leaves was the most likely explanation for more movement away from lower plant regions. Although larvae on flowering plants did not move further up or down than larvae on non-flowering plants, they more often departed the leaflet (within a leaf) where they eclosed. The final distribution of larvae was affected by plant genotype, with larvae on flowering plants found less often on leaflets and more often on stipules, tendrils and reproductive structures. Understanding intra-plant movement by herbivorous insects under natural conditions is important because such movement determines the value of economic loss to host crops. Knowing the behaviour underlying the spatial distribution of herbivores on plants will assist us to interpret field data and should lead to better informed pest management decisions.

  19. Analysis of links between groundwater recharge and discharge areas and wetland plant communities distribution in Middle Biebrza Basin, Poland

    NASA Astrophysics Data System (ADS)

    Grygoruk, Mateusz; Batelaan, Okke; Okruszko, Tomasz; Kotowski, Wiktor; Rycharski, Marek; Chormanski, Jaroslaw; Miroslaw-Swiatek, Dorota

    2010-05-01

    Natural evolution of wetlands is strongly dependent on groundwater dynamics, soil aeration and climate. These environmental factors determine the constant development of wetland plant communities and peat forming processes. Depending on spatial distribution of groundwater flow systems and recharge and discharge conditions, shallow groundwater can also be influenced by phreatophytic plants. Such feedback plays an important role in wetland development, especially when landuse or climate changes occur. Thus, understanding the links between dynamics of biotopic and biocenotic relations is crucial for wetland management aimed at the comprehensive set of conservation strategies. Main aim of this study was to review links between valuable wetland plant communities and the groundwater recharge/discharge conditions of particular habitats of Middle Biebrza Basin, Poland. The study area consists of various types of wetland landscapes, of which the dominant are fens. Organogenic top layer is intersected locally by sandy dunes and glaci-fluvial residual plateaus. The northern boundary of the study area is covered with an outwash plateau. A three-dimensional regional groundwater flow model was set up to quantify groundwater system and flow paths. Model calibration involved measured heads of the unconfined organogenic top layer and the underlaying, confined sandy aquifer. Measured thickness of unsaturated zone as well as physical parameters of organogenic layer were taken into account in interpretation of shallow groundwater dynamics. Recharge to groundwater was spatially distributed in accordance to analysis of measured precipitation-groundwater level relationships. Cell-by-cell flow analysis and groundwater exfiltration analysis were applied to map groundwater recharge and discharge areas within the modelled area. Results of groundwater modelling were validated with phytosociologic research combined with remote-sensing based spatial analysis of wetland habitats distribution

  20. Distribution and status of Vicia menziesii Spreng. (Leguminosae): Hawaii's first officially listed endangered plant species