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Sample records for distancia entre plantas

  1. In planta gene targeting

    PubMed Central

    Fauser, Friedrich; Roth, Nadine; Pacher, Michael; Ilg, Gabriele; Sánchez-Fernández, Rocío; Biesgen, Christian; Puchta, Holger

    2012-01-01

    The development of designed site-specific endonucleases boosted the establishment of gene targeting (GT) techniques in a row of different species. However, the methods described in plants require a highly efficient transformation and regeneration procedure and, therefore, can be applied to very few species. Here, we describe a highly efficient GT system that is suitable for all transformable plants regardless of transformation efficiency. Efficient in planta GT was achieved in Arabidopsis thaliana by expression of a site-specific endonuclease that not only cuts within the target but also the chromosomal transgenic donor, leading to an excised targeting vector. Progeny clonal for the targeted allele could be obtained directly by harvesting seeds. Targeted events could be identified up to approximately once per 100 seeds depending on the target donor combination. Molecular analysis demonstrated that, in almost all events, homologous recombination occurred at both ends of the break. No ectopic integration of the GT vector was found. PMID:22529367

  2. PREJUICIO Y DISTANCIA SOCIAL HACIA PERSONAS HOMOSEXUALES POR PARTE DE JÓVENES UNIVERSITARIOS

    PubMed Central

    Fernández Rodríguez, María del C.; Squiabro, José Calderón

    2014-01-01

    Se realizó un estudio descriptivo transversal con el propósito de explorar actitudes de rechazo y distancia social hacia las personas gays y lesbianas (GL) en 565 universitarios. Se utilizó una escala para medir Prejuicio y otra escala para medir Distancia Social. Los participantes reflejaron niveles moderados de prejuicio y distancia social (DS) hacia las personas gays y lesbianas. Los varones (M=104.5, DT= 27.47) mostraron significativamente más prejuicio que las mujeres (M=98.8, DT= 23.41). Los hombres (M=22.7, DT= 7.00) mostraron significativamente mayor DS que las mujeres (M=21.1, DT= 5.41). Las personas que asisten con regularidad a la iglesia mostraron más prejuicio y DS que los que no asisten. Se analiza importancia de incluir el tema de la diversidad sexual a través del currículo para desmontar prejuicios hacia la comunidad homosexual. PMID:25606066

  3. Exploring Strategies of Assessment and Results in the Spanish Universidad Nacional de Educacion a Distancia and the United Kingdom Open University.

    ERIC Educational Resources Information Center

    James, Arthur

    The strategies of student evaluation and the patterns of results are compared for The Universidad Nacional de Educacion a Distancia (UNED) in Spain and The Open University of The United Kingdom. Both universities operate a system of undergraduate subject credits leading to a degree, but the length of the courses of the two systems differ. UNED…

  4. Comparisons in the Organisation, Methods, and Results of the Universidad Nacional de Educacion a Distancia (Spain) and The Open University of The United Kingdom.

    ERIC Educational Resources Information Center

    James, Arthur

    The organization, methods, and outcomes of the distance education systems at the Universidad Nacional de Educacion a Distancia (UNED) in Spain and The Open University of the United Kingdom are compared. The following topics are covered: higher education in Spain, UNED's ideology, student characteristics in both universities, organization,…

  5. Hyperthermophilic endoglucanase for in planta lignocellulose conversion

    PubMed Central

    2012-01-01

    Background The enzymatic conversion of lignocellulosic plant biomass into fermentable sugars is a crucial step in the sustainable and environmentally friendly production of biofuels. However, a major drawback of enzymes from mesophilic sources is their suboptimal activity under established pretreatment conditions, e.g. high temperatures, extreme pH values and high salt concentrations. Enzymes from extremophiles are better adapted to these conditions and could be produced by heterologous expression in microbes, or even directly in the plant biomass. Results Here we show that a cellulase gene (sso1354) isolated from the hyperthermophilic archaeon Sulfolobus solfataricus can be expressed in plants, and that the recombinant enzyme is biologically active and exhibits the same properties as the wild type form. Since the enzyme is inactive under normal plant growth conditions, this potentially allows its expression in plants without negative effects on growth and development, and subsequent heat-inducible activation. Furthermore we demonstrate that the recombinant enzyme acts in high concentrations of ionic liquids and can therefore degrade α-cellulose or even complex cell wall preparations under those pretreatment conditions. Conclusion The hyperthermophilic endoglucanase SSO1354 with its unique features is an excellent tool for advanced biomass conversion. Here we demonstrate its expression in planta and the possibility for post harvest activation. Moreover the enzyme is suitable for combined pretreatment and hydrolysis applications. PMID:22928996

  6. In planta passive sampling devices for assessing subsurface chlorinated solvents.

    PubMed

    Shetty, Mikhil K; Limmer, Matt A; Waltermire, Kendra; Morrison, Glenn C; Burken, Joel G

    2014-06-01

    Contaminant concentrations in trees have been used to delineate groundwater contaminant plumes (i.e., phytoscreening); however, variability in tree composition hinders accurate measurement of contaminant concentrations in planta, particularly for long-term monitoring. This study investigated in planta passive sampling devices (PSDs), termed solid phase samplers (SPSs) to be used as a surrogate tree core. Characteristics studied for five materials included material-air partitioning coefficients (Kma) for chlorinated solvents, sampler equilibration time and field suitability. The materials investigated were polydimethylsiloxane (PDMS), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), polyoxymethylene (POM) and plasticized polyvinyl chloride (PVC). Both PDMS and LLDPE samplers demonstrated high partitioning coefficients and diffusivities and were further tested in greenhouse experiments and field trials. While most of the materials could be used for passive sampling, the PDMS SPSs performed best as an in planta sampler. Such a sampler was able to accurately measure trichloroethylene (TCE) and tetrachloroethylene (PCE) concentrations while simultaneously incorporating simple operation and minimal impact to the surrounding property and environment. PMID:24268175

  7. Plantas crucíferas y la prevención del cáncer

    Cancer.gov

    Hoja informativa que resume los resultados de estudios sobre las plantas crucíferas y el cáncer. Incluye una lista de plantas crucíferas y las guías alimentarias recomendadas para el consumo de verduras.

  8. Accidentes en plantas nucleares de electricidad y el riesgo de cáncer

    Cancer.gov

    Hoja informativa acerca de los riesgos del cáncer asociados con accidentes en plantas nucleares de electricidad. Incluye información para pacientes con cáncer que viven en una zona que puede haber sido afectada por un accidente en una planta nuclear.

  9. In planta Agrobacterium-mediated transformation by vacuum infiltration.

    PubMed

    Tague, Brian W; Mantis, Joanna

    2006-01-01

    In planta Agrobacterium-mediated transformation using vacuum infiltration results in transgenic Arabidopsis thaliana without the use of sterile conditions or plant regeneration. Plants are grown in pots, in standard potting mix. Agrobacterium tumefaciens, carrying an appropriate plant transformation vector, is suspended in an infiltration medium that contains, at a minimum, sucrose and the surfactant Silwet L-77. Flower buds are immersed in the suspension of A. tumefaciens. The application of a vacuum drives the bacteria into the intercellular air spaces. A portion of the Agrobacterium Ti plasmid known as the T-DNA region, which has been engineered to carry a selectable marker, becomes integrated into the plant genomic DNA. Plants are allowed to set seed. Seeds are germinated in selective conditions to recover transformants. PMID:16739579

  10. Effets Josephson generalises entre antiferroaimants et entre supraconducteurs antiferromagnetiques

    NASA Astrophysics Data System (ADS)

    Chasse, Dominique

    L'effet Josephson est generalement presente comme le resultat de l'effet tunnel coherent de paires de Cooper a travers une jonction tunnel entre deux supraconducteurs, mais il est possible de l'expliquer dans un contexte plus general. Par exemple, Esposito & al. ont recemment demontre que l'effet Josephson DC peut etre decrit a l'aide du boson pseudo-Goldstone de deux systemes couples brisant chacun la symetrie abelienne U(1). Puisque cette description se generalise de facon naturelle a des brisures de symetries continues non-abeliennes, l'equivalent de l'effet Josephson devrait donc exister pour des types d'ordre a longue portee differents de la supraconductivite. Le cas de deux ferroaimants itinerants (brisure de symetrie 0(3)) couples a travers une jonction tunnel a deja ete traite dans la litterature Afin de mettre en evidence la generalite du phenomene et dans le but de faire des predictions a partir d'un modele realiste, nous etudions le cas d'une jonction tunnel entre deux antiferroaimants itinerants. En adoptant une approche Similaire a celle d'Ambegaokar & Baratoff pour une jonction Josephson, nous trouvons un courant d'aimantation alternee a travers la jonction qui est proportionnel a sG x sD ou fG et sD sont les vecteurs de Neel de part et d'autre de la jonction. La fonction sinus caracteristique du courant Josephson standard est donc remplacee.ici par un produit vectoriel. Nous montrons que, d'un point de vue microscopique, ce phenomene resulte de l'effet tunnel coherent de paires particule-trou de spin 1 et de vecteur d'onde net egal au vecteur d'onde antiferromagnetique Q. Nous trouvons egalement la dependance en temperature de l'analogue du courant critique. En presence d'un champ magnetique externe, nous obtenons l'analogue de l'effet Josephson AC et la description complete que nous en donnons s'applique aussi au cas d'une jonction tunnel entre ferroaimants (dans ce dernier cas, les traitements anterieurs de cet effet AC s'averent incomplets). Nous considerons ensuite le cas d'une jonction tunnel entre deux materiaux au sein desquels l'antiferromagnetisme itinerant et la supraconductivite de type d coexistent de facon homogene. Nous obtenons a nouveau un courant d'aimantation alternee proportionnel a sG x sD, mais l'amplitude de l'analogue du courant critique est modulee par l'energie Josephson de la jonction E oc cos Acp, ou Acp est la difference de phase entre les deux parametres d'ordre supraconducteurs. Symetriquement, le courant Josephson supraconducteur est proportionnel a sin Acp, mais le courant critique est module par l'energie de couplage entre les moments magnetiques alternes ES cx SG· SD.

  11. Time Gating of Chloroplast Autofluorescence Allows Clearer Fluorescence Imaging In Planta

    PubMed Central

    Kodama, Yutaka

    2016-01-01

    Chloroplast, an organelle facilitating photosynthesis, exhibits strong autofluorescence, which is an undesired background signal that restricts imaging experiments with exogenous fluorophore in plants. In this study, the autofluorescence was characterized in planta under confocal laser microscopy, and it was found that the time-gated imaging technique completely eliminates the autofluorescence. As a demonstration of the technique, a clearer signal of fluorescent protein-tagged phototropin, a blue-light photoreceptor localized at the chloroplast periphery, was visualized in planta. PMID:27027881

  12. Antifreeze Proteins Modify the Freezing Process In Planta12

    PubMed Central

    Griffith, Marilyn; Lumb, Chelsey; Wiseman, Steven B.; Wisniewski, Michael; Johnson, Robert W.; Marangoni, Alejandro G.

    2005-01-01

    During cold acclimation, winter rye (Secale cereale L. cv Musketeer) plants accumulate antifreeze proteins (AFPs) in the apoplast of leaves and crowns. The goal of this study was to determine whether these AFPs influence survival at subzero temperatures by modifying the freezing process or by acting as cryoprotectants. In order to inhibit the growth of ice, AFPs must be mobile so that they can bind to specific sites on the ice crystal lattice. Guttate obtained from cold-acclimated winter rye leaves exhibited antifreeze activity, indicating that the AFPs are free in solution. Infrared video thermography was used to observe freezing in winter rye leaves. In the absence of an ice nucleator, AFPs had no effect on the supercooling temperature of the leaves. However, in the presence of an ice nucleator, AFPs lowered the temperature at which the leaves froze by 0.3°C to 1.2°C. In vitro studies showed that apoplastic proteins extracted from cold-acclimated winter rye leaves inhibited the recrystallization of ice and also slowed the rate of migration of ice through solution-saturated filter paper. When we examined the possible role of winter rye AFPs in cryoprotection, we found that lactate dehydrogenase activity was higher after freezing in the presence of AFPs compared with buffer, but the same effect was obtained by adding bovine serum albumin. AFPs had no effect on unstacked thylakoid volume after freezing, but did inhibit stacking of the thylakoids, thus indicating a loss of thylakoid function. We conclude that rye AFPs have no specific cryoprotective activity; rather, they interact directly with ice in planta and reduce freezing injury by slowing the growth and recrystallization of ice. PMID:15805474

  13. Secretome analysis of the rice bacterium Xanthomonas oryzae (Xoo) using in vitro and in planta systems.

    PubMed

    Wang, Yiming; Kim, Sang Gon; Wu, Jingni; Huh, Hyun-Hye; Lee, Su-Ji; Rakwal, Randeep; Agrawal, Ganesh Kumar; Park, Zee-Yong; Young Kang, Kyu; Kim, Sun Tae

    2013-06-01

    Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight disease in rice, and that severely affects yield loss (upto 50%) of total rice production. Here, we report a proteomics investigation of Xoo (compatible race K3)-secreted proteins, isolated from its in vitro culture and in planta infected rice leaves. 2DE coupled with MALDI-TOF-MS and/or nLC-ESI-MS/MS approaches identified 139 protein spots (out of 153 differential spots), encoding 109 unique proteins. Identified proteins belonged to multiple biological and molecular functions. Metabolic and nutrient uptake proteins were common up to both in vitro and in planta secretomes. However, pathogenicity, protease/peptidase, and host defense-related proteins were highly or specifically expressed during in planta infection. A good correlation was observed between protein and transcript abundances for nine proteins secreted in planta as per semiquantitative RT-PCR analysis. Transgenic rice leaf sheath (carrying PBZ1 promoter::GFP cell death reporter), when used to express a few of the identified secretory proteins, showed a direct activation of cell death signaling, suggesting their involvement in pathogenicity related with secretion effectors. This work furthers our understanding of rice bacterial blight disease, and serves as a resource for possible translation in generating disease resistant rice plants for improved seed yield. PMID:23512849

  14. IN PLANTA AGRIONFECTION BY CANADIAN AND GERMAN POTATO LEAFROLL VIRUS FULL-LENGTH CDNAS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Full-length infectious cDNA clones of Canadain (PLRV-flc)and German (PLRV-flg) Potato leafroll virus isolates were constructed and their biological activities examined in planta. For both constructs, agroinfection by PLRV cDNA resulted in virus mulitplication in the primary leaf followed by systemi...

  15. Chlamydiae Has Contributed at Least 55 Genes to Plantae with Predominantly Plastid Functions

    PubMed Central

    Bhattacharya, Debashish

    2008-01-01

    Background The photosynthetic organelle (plastid) originated via primary endosymbiosis in which a phagotrophic protist captured and harnessed a cyanobacterium. The plastid was inherited by the common ancestor of the red, green (including land plants), and glaucophyte algae (together, the Plantae). Despite the critical importance of primary plastid endosymbiosis, its ancient derivation has left behind very few “footprints” of early key events in organelle genesis. Methodology/Principal Findings To gain insights into this process, we conducted an in-depth phylogenomic analysis of genomic data (nuclear proteins) from 17 Plantae species to identify genes of a surprising provenance in these taxa, Chlamydiae bacteria. Previous studies show that Chlamydiae contributed many genes (at least 21 in one study) to Plantae that primarily have plastid functions and were postulated to have played a fundamental role in organelle evolution. Using our comprehensive approach, we identify at least 55 Chlamydiae-derived genes in algae and plants, of which 67% (37/55) are putatively plastid targeted and at least 3 have mitochondrial functions. The remainder of the proteins does not contain a bioinformatically predicted organelle import signal although one has an N-terminal extension in comparison to the Chlamydiae homolog. Our data suggest that environmental Chlamydiae were significant contributors to early Plantae genomes that extend beyond plastid metabolism. The chlamydial gene distribution and protein tree topologies provide evidence for both endosymbiotic gene transfer and a horizontal gene transfer ratchet driven by recurrent endoparasitism as explanations for gene origin. Conclusions/Significance Our findings paint a more complex picture of gene origin than can easily be explained by endosymbiotic gene transfer from an organelle-like point source. These data significantly extend the genomic impact of Chlamydiae on Plantae and show that about one-half (30/55) of the transferred genes are most closely related to sequences emanating from the genome of the only environmental isolate that is currently available. This strain, Candidatus Protochlamydia amoebophila UWE25 is an endosymbiont of Acanthamoeba and likely represents the type of endoparasite that contributed the genes to Plantae. PMID:18493612

  16. Time-weighted average SPME analysis for in planta determination of cVOCs.

    PubMed

    Sheehan, Emily M; Limmer, Matt A; Mayer, Philipp; Karlson, Ulrich Gosewinkel; Burken, Joel G

    2012-03-20

    The potential of phytoscreening for plume delineation at contaminated sites has promoted interest in innovative, sensitive contaminant sampling techniques. Solid-phase microextraction (SPME) methods have been developed, offering quick, undemanding, noninvasive sampling without the use of solvents. In this study, time-weighted average SPME (TWA-SPME) sampling was evaluated for in planta quantification of chlorinated solvents. TWA-SPME was found to have increased sensitivity over headspace and equilibrium SPME sampling. Using a variety of chlorinated solvents and a polydimethylsiloxane/carboxen (PDMS/CAR) SPME fiber, most compounds exhibited near linear or linear uptake over the sampling period. Smaller, less hydrophobic compounds exhibited more nonlinearity than larger, more hydrophobic molecules. Using a specifically designed in planta sampler, field sampling was conducted at a site contaminated with chlorinated solvents. Sampling with TWA-SPME produced instrument responses ranging from 5 to over 200 times higher than headspace tree core sampling. This work demonstrates that TWA-SPME can be used for in planta detection of a broad range of chlorinated solvents and methods can likely be applied to other volatile and semivolatile organic compounds. PMID:22332592

  17. In planta anthocyanin degradation by a vacuolar class III peroxidase in Brunfelsia calycina flowers.

    PubMed

    Zipor, Gadi; Duarte, Patrícia; Carqueijeiro, Inês; Shahar, Liat; Ovadia, Rinat; Teper-Bamnolker, Paula; Eshel, Dani; Levin, Yishai; Doron-Faigenboim, Adi; Sottomayor, Mariana; Oren-Shamir, Michal

    2015-01-01

    In contrast to detailed knowledge regarding the biosynthesis of anthocyanins, the largest group of plant pigments, little is known about their in planta degradation. It has been suggested that anthocyanin degradation is enzymatically controlled and induced when beneficial to the plant. Here we investigated the enzymatic process in Brunfelsia calycina flowers, as they changed color from purple to white. We characterized the enzymatic process by which B. calycina protein extracts degrade anthocyanins. A candidate peroxidase was partially purified and characterized and its intracellular localization was determined. The transcript sequence of this peroxidase was fully identified. A basic peroxidase, BcPrx01, is responsible for the in planta degradation of anthocyanins in B. calycina flowers. BcPrx01 has the ability to degrade complex anthocyanins, it co-localizes with these pigments in the vacuoles of petals, and both the mRNA and protein levels of BcPrx01 are greatly induced parallel to the degradation of anthocyanins. Both isoelectric focusing (IEF) gel analysis and 3D structure prediction indicated that BcPrx01 is cationic. Identification of BcPrx01 is a significant breakthrough both in the understanding of anthocyanin catabolism in plants and in the field of peroxidases, where such a consistent relationship between expression levels, in planta subcellular localization and activity has seldom been demonstrated. PMID:25256351

  18. Screening for in planta protein-protein interactions combining bimolecular fluorescence complementation with flow cytometry

    PubMed Central

    2012-01-01

    Understanding protein and gene function requires identifying interaction partners using biochemical, molecular or genetic tools. In plants, searching for novel protein-protein interactions is limited to protein purification assays, heterologous in vivo systems such as the yeast-two-hybrid or mutant screens. Ideally one would be able to search for novel protein partners in living plant cells. We demonstrate that it is possible to screen for novel protein-protein interactions from a random library in protoplasted Arabidopsis plant cells and recover some of the interacting partners. Our screen is based on capturing the bi-molecular complementation of mYFP between an YN-bait fusion partner and a completely random prey YC-cDNA library with FACS. The candidate interactions were confirmed using in planta BiFC assays and in planta FRET-FLIM assays. From this work, we show that the well characterized protein Calcium Dependent Protein Kinase 3 (CPK3) interacts with APX3, HMGB5, ORP2A and a ricin B-related lectin domain containing protein At2g39050. This is one of the first randomin planta screens to be successfully employed. PMID:22789293

  19. Highly Efficient Agrobacterium-Mediated Transformation of Wheat Via In Planta Inoculation

    NASA Astrophysics Data System (ADS)

    Risacher, Thierry; Craze, Melanie; Bowden, Sarah; Paul, Wyatt; Barsby, Tina

    This chapter details a reproducible method for the transformation of spring wheat using Agrobacterium tumefaciens via the direct inoculation of bacteria into immature seeds in planta as described in patent WO 00/63398(1. Transformation efficiencies from 1 to 30% have been obtained and average efficiencies of at least 5% are routinely achieved. Regenerated plants are phenotypically normal with 30-50% of transformation events carrying introduced genes at single insertion sites, a higher rate than is typically reported for transgenic plants produced using biolistic transformation methods.

  20. i Planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This application was designed for farmers, agriculture researchers, and gardeners. The application includes a calculator, a data logger, and a GPS mapping function. It was designed for vegetable farming but can be used for open field applications. The calculator solves for the amount of pesticide,...

  1. Comparative analysis of the in vitro and in planta secretomes from Mycosphaerella fijiensis isolates.

    PubMed

    Escobar-Tovar, Lina; Guzmán-Quesada, Mauricio; Sandoval-Fernández, Jorge A; Gómez-Lim, Miguel A

    2015-06-01

    Black Sigatoka, a devastating disease of bananas and plantains worldwide, is caused by the fungus Mycosphaerella fijiensis. Several banana cultivars such as 'Yangambi Km 5' and Calcutta IV, have been known to be resistant to the fungus, but the resistance has been broken in 'Yangambi Km 5' in Costa Rica. Since the resistance of this variety still persists in Mexico, the aim of this study was to compare the in vitro and in planta secretomes from two avirulent and virulent M. fijiensis isolates using proteomics and bioinformatics approaches. We aimed to identify differentially expressed proteins in fungal isolates that differ in pathogenicity and that might be responsible for breaking the resistance in 'Yangambi Km 5'. We were able to identify 90 protein spots in the secretomes of fungal isolates encoding 42 unique proteins and 35 differential spots between them. Proteins involved in carbohydrate transport and metabolism were more prevalent. Several proteases, pathogenicity-related, ROS detoxification and unknown proteins were also highly or specifically expressed by the virulent isolate in vitro or during in planta infection. An unknown protein representing a virulence factor candidate was also identified. These results demonstrated that the secretome reflects major differences between both M. fijiensis isolates. PMID:25986542

  2. Bcmimp1, a Botrytis cinerea Gene Transiently Expressed in planta, Encodes a Mitochondrial Protein

    PubMed Central

    Benito-Pescador, David; Santander, Daniela; Arranz, M.; Díaz-Mínguez, José M.; Eslava, Arturo P.; van Kan, Jan A. L.; Benito, Ernesto P.

    2016-01-01

    Botrytis cinerea is a widespread necrotrophic fungus which infects more than 200 plant species. In an attempt to characterize the physiological status of the fungus in planta and to identify genetic factors contributing to its ability to infect the host cells, a differential gene expression analysis during the interaction B. cinerea-tomato was carried out. Gene Bcmimp1 codes for a mRNA detected by differential display in the course of this analysis. During the interaction with the host, it shows a transient expression pattern with maximal expression levels during the colonization and maceration of the infected tissues. Bioinformatic analysis suggested that BCMIMP1 is an integral membrane protein located in the mitochondrial inner membrane. Co-localization experiments with a BCMIMP1-GFP fusion protein confirmed that the protein is targeted to the mitochondria. ΔBcmimp1 mutants do not show obvious phenotypic differences during saprophytic growth and their infection ability was unaltered as compared to the wild-type. Interestingly, the mutants produced increased levels of reactive oxygen species, likely as a consequence of disturbed mitochondrial function. Although Bcmimp1 expression is enhanced in planta it cannot be considered a pathogenicity factor. PMID:26952144

  3. In-planta Sporulation Capacity Enhances Infectivity and Rhizospheric Competitiveness of Frankia Strains

    PubMed Central

    Cotin-Galvan, Laetitia; Pozzi, Adrien C.; Schwob, Guillaume; Fournier, Pascale; Fernandez, Maria P.; Herrera-Belaroussi, Aude

    2016-01-01

    Frankia Sp+ strains maintain their ability to sporulate in symbiosis with actinorhizal plants, producing abundant sporangia inside host plant cells, in contrast to Sp− strains, which are unable to perform in-planta sporulation. We herein examined the role of in-planta sporulation in Frankia infectivity and competitiveness for root infection. Fifteen strains belonging to different Sp+ and Sp− phylogenetic lineages were inoculated on seedlings of Alnus glutinosa (Ag) and A. incana (Ai). Strain competitiveness was investigated by performing Sp−/Sp+ co-inoculations. Plant inoculations were standardized using crushed nodules obtained under laboratory-controlled conditions (same plant species, age, and environmental factors). Specific oligonucleotide primers were developed to identify Frankia Sp+ and/or Sp− strains in the resulting nodules. Single inoculation experiments showed that (i) infectivity by Sp+ strains was significantly greater than that by Sp− strains, (ii) genetically divergent Sp+ strains exhibited different infective abilities, and (iii) Sp+ and Sp− strains showed different host preferences according to the origin (host species) of the inocula. Co-inoculations of Sp+ and Sp− strains revealed the greater competitiveness of Sp+ strains (98.3 to 100% of Sp+ nodules, with up to 15.6% nodules containing both Sp+ and Sp− strains). The results of the present study highlight differences in Sp+/Sp− strain ecological behaviors and provide new insights to strengthen the obligate symbiont hypothesis for Sp+ strains. PMID:26726131

  4. Bcmimp1, a Botrytis cinerea Gene Transiently Expressed in planta, Encodes a Mitochondrial Protein.

    PubMed

    Benito-Pescador, David; Santander, Daniela; Arranz, M; Díaz-Mínguez, José M; Eslava, Arturo P; van Kan, Jan A L; Benito, Ernesto P

    2016-01-01

    Botrytis cinerea is a widespread necrotrophic fungus which infects more than 200 plant species. In an attempt to characterize the physiological status of the fungus in planta and to identify genetic factors contributing to its ability to infect the host cells, a differential gene expression analysis during the interaction B. cinerea-tomato was carried out. Gene Bcmimp1 codes for a mRNA detected by differential display in the course of this analysis. During the interaction with the host, it shows a transient expression pattern with maximal expression levels during the colonization and maceration of the infected tissues. Bioinformatic analysis suggested that BCMIMP1 is an integral membrane protein located in the mitochondrial inner membrane. Co-localization experiments with a BCMIMP1-GFP fusion protein confirmed that the protein is targeted to the mitochondria. ΔBcmimp1 mutants do not show obvious phenotypic differences during saprophytic growth and their infection ability was unaltered as compared to the wild-type. Interestingly, the mutants produced increased levels of reactive oxygen species, likely as a consequence of disturbed mitochondrial function. Although Bcmimp1 expression is enhanced in planta it cannot be considered a pathogenicity factor. PMID:26952144

  5. Simultaneous specific in planta visualization of root-colonizing fungi using fluorescence in situ hybridization (FISH).

    PubMed

    Vági, Pál; Knapp, Dániel G; Kósa, Annamária; Seress, Diána; Horváth, Áron N; Kovács, Gábor M

    2014-05-01

    In planta detection of mutualistic, endophytic, and pathogenic fungi commonly colonizing roots and other plant organs is not a routine task. We aimed to use fluorescence in situ hybridization (FISH) for simultaneous specific detection of different fungi colonizing the same tissue. We have adapted ribosomal RNA (rRNA) FISH for visualization of common mycorrhizal (arbuscular- and ectomycorrhiza) and endophytic fungi within roots of different plant species. Beside general probes, we designed and used specific ones hybridizing to the large subunit of rRNA with fluorescent dyes chosen to avoid or reduce the interference with the autofluorescence of plant tissues. We report here an optimized efficient protocol of rRNA FISH and the use of both epifluorescence and confocal laser scanning microscopy for simultaneous specific differential detection of those fungi colonizing the same root. The method could be applied for the characterization of other plant-fungal interactions, too. In planta FISH with specific probes labeled with appropriate fluorescent dyes could be used not only in basic research but to detect plant colonizing pathogenic fungi in their latent life-period. PMID:24221902

  6. In-planta Sporulation Capacity Enhances Infectivity and Rhizospheric Competitiveness of Frankia Strains.

    PubMed

    Cotin-Galvan, Laetitia; Pozzi, Adrien C; Schwob, Guillaume; Fournier, Pascale; Fernandez, Maria P; Herrera-Belaroussi, Aude

    2016-03-26

    Frankia Sp+ strains maintain their ability to sporulate in symbiosis with actinorhizal plants, producing abundant sporangia inside host plant cells, in contrast to Sp- strains, which are unable to perform in-planta sporulation. We herein examined the role of in-planta sporulation in Frankia infectivity and competitiveness for root infection. Fifteen strains belonging to different Sp+ and Sp- phylogenetic lineages were inoculated on seedlings of Alnus glutinosa (Ag) and A. incana (Ai). Strain competitiveness was investigated by performing Sp-/Sp+ co-inoculations. Plant inoculations were standardized using crushed nodules obtained under laboratory-controlled conditions (same plant species, age, and environmental factors). Specific oligonucleotide primers were developed to identify Frankia Sp+ and/or Sp- strains in the resulting nodules. Single inoculation experiments showed that (i) infectivity by Sp+ strains was significantly greater than that by Sp- strains, (ii) genetically divergent Sp+ strains exhibited different infective abilities, and (iii) Sp+ and Sp- strains showed different host preferences according to the origin (host species) of the inocula. Co-inoculations of Sp+ and Sp- strains revealed the greater competitiveness of Sp+ strains (98.3 to 100% of Sp+ nodules, with up to 15.6% nodules containing both Sp+ and Sp- strains). The results of the present study highlight differences in Sp+/Sp- strain ecological behaviors and provide new insights to strengthen the obligate symbiont hypothesis for Sp+ strains. PMID:26726131

  7. Inhibition of Fungal and Bacterial Plant Pathogens In Vitro and In Planta with Ultrashort Cationic Lipopeptides?

    PubMed Central

    Makovitzki, Arik; Viterbo, Ada; Brotman, Yariv; Chet, Ilan; Shai, Yechiel

    2007-01-01

    Plant diseases constitute an emerging threat to global food security. Many of the currently available antimicrobial agents for agriculture are highly toxic and nonbiodegradable and cause extended environmental pollution. Moreover, an increasing number of phytopathogens develop resistance to them. Recently, we have reported on a new family of ultrashort antimicrobial lipopeptides which are composed of only four amino acids linked to fatty acids (A. Makovitzki, D. Avrahami, and Y. Shai, Proc. Natl. Acad. Sci. USA 103:15997-16002, 2006). Here, we investigated the activities in vitro and in planta and the modes of action of these short lipopeptides against plant-pathogenic bacteria and fungi. They act rapidly, at low micromolar concentrations, on the membranes of the microorganisms via a lytic mechanism. In vitro microscopic analysis revealed wide-scale damage to the microorganism's membrane, in addition to inhibition of pathogen growth. In planta potent antifungal activity was demonstrated on cucumber fruits and leaves infected with the pathogen Botrytis cinerea as well as on corn leaves infected with Cochliobolus heterostrophus. Similarly, treatment with the lipopeptides of Arabidopsis leaves infected with the bacterial leaf pathogen Pseudomonas syringae efficiently and rapidly reduced the number of bacteria. Importantly, in contrast to what occurred with many native lipopeptides, no toxicity was observed on the plant tissues. These data suggest that the ultrashort lipopeptides could serve as native-like antimicrobial agents economically feasible for use in plant protection. PMID:17720828

  8. Mexican papita viroid and tomato planta macho viroid belong to a single species in the genus Pospiviroid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato planta macho viroid (TPMVd) and Mexican papita viroid (MPVd) are two closely-related (>90% sequence identity) members of the genus Pospiviroid. Their current status as separate species is based upon the reported ability of TPMVd to replicate in Gomphrena globosa and the inability of this viro...

  9. In Planta Response of Arabidopsis to Photothermal Impact Mediated by Gold Nanoparticles.

    PubMed

    Koo, Yeonjong; Lukianova-Hleb, Ekaterina Y; Pan, Joann; Thompson, Sean M; Lapotko, Dmitri O; Braam, Janet

    2016-02-01

    Biological responses to photothermal effects of gold nanoparticles (GNPs) have been demonstrated and employed for various applications in diverse systems except for one important class - plants. Here, the uptake of GNPs through Arabidopsis thaliana roots and translocation to leaves are reported. Successful plasmonic nanobubble generation and acoustic signal detection in planta is demonstrated. Furthermore, Arabidopsis leaves harboring GNPs and exposed to continuous laser or noncoherent light show elevated temperatures across the leaf surface and induced expression of heat-shock regulated genes. Overall, these results demonstrate that Arabidopsis can readily take up GNPs through the roots and translocate the particles to leaf tissues. Once within leaves, GNPs can act as photothermal agents for on-demand remote activation of localized biological processes in plants. PMID:26662357

  10. In planta transformation method for T-DNA transfer in orchids

    NASA Astrophysics Data System (ADS)

    Semiarti, Endang; Purwantoro, Aziz; Mercuriani, Ixora S.; Anggriasari, Anida M.; Jang, Seonghoe; Suhandono, Sony; Machida, Yasunori; Machida, Chiyoko

    2014-03-01

    Transgenic plant technology is an efficient tool to study the function of gene(s) in plant. The most popular and widely used technique is Agrobacterium-mediated transformation in which cocultivation was done by immersing the plant tissues/organ in overnight bacterial cultured for about 30 minutes to one hour under in vitro condition. In this experiment, we developed more easier technique that omitted the in vitro step during cocultivation with Agrobacterium, namely in planta transformation method. Pollinaria (compact pollen mass of orchid) of Phalaenopsis amabilis and Spathoglottis plicata orchids were used as target explants that were immersed into bacterial culture for 30 minutes, then dried up the pollinaria, the transformed pollinaria was used to pollinate orchid flowers. The T-DNA used for this experiments were Ubipro∷PaFT/A. tumefaciens GV3101 for P. amabilis and MeEF1α2 pro∷GUS/ A. tumefaciens LBA 4404 for S.plicata. Seeds that were produced from pollinated flowers were grown onto 10 mg/l hygromicin containing NP (New Phalaenopsis) medium. The existance of transgene in putative transformant protocorm (developing orchid embryo) genome was confirmed using PCR with specific primers of either PaFT or GUS genes. Histochemical GUS assay was also performed to the putative transformants. The result showed that transformation frequencies were 2.1 % in P. amabilis, and 0,53% in S. plicata. These results indicates that in planta transformation method could be used for Agrobacterium-mediated genetic transformation, with advantage easier and more secure work from contaminants than that of the in vitro method.

  11. Transformation of the ryegrass endophyte Neotyphodium lolii can alter its in planta mycelial morphology.

    PubMed

    Zhang, Ningxin; Scott, Vicki; Al-Samarrai, Taha H; Tan, Yong Y; Spiering, Martin J; McMillan, Lisa K; Lane, Geoffrey A; Scott, D Barry; Christensen, Michael J; Schmid, Jan

    2006-05-01

    The fungus Neotyphodium lolii grows in the intercellular spaces of perennial ryegrass as a mutualistic endosymbiont. One of the benefits it conveys to the plant is the production of alkaloids toxic to herbivores. We wanted to determine in planta expression patterns of the N. lolii 3-hydroxy-3-methylglutaryl-CoA reductase (HMG CoA reductase) gene, believed to be involved in the synthesis of two of these alkaloid toxins, lolitrem B and ergovaline. We transformed the N. lolii strain Lp19 with plasmids, in which DNA fragments upstream of the open reading frame of the N. lolii HMG CoA reductase gene controlled expression of the GUS (gusA; Escherichia coli beta-glucuronidase) reporter gene. In exponentially growing cultures, the GUS gene was not expressed if the length of upstream sequence was less than 400 bp, and >1100 bp were required for maximum expression. When reintroduced into ryegrass plants, transformants often showed highly increased hyphal branching compared to the wild-type parent strain, although in culture their growth kinetics and morphology were indistinguishable from that of the wild-type. Deterioration of hyphae and the hypha-plant interface occurred and in one transformant reduced tillering (formation of new plants, referred to in agronomy as tillers) and death of infected plants. We found no evidence that these abnormalities were caused by interference of the construct with the function of the native gene, as judged by analysis of the site of integration of the promoter-GUS cassette, expression of the native gene and lolitrem B and ergovaline levels in infected plants. However, there was some correlation between GUS expression and the degree of hyphal branching, suggesting that high levels of beta-glucuronidase may disturb the symbiotic interaction. Levels of another alkaloid, peramine, were also not significantly affected by transformation. In previous studies increased in planta branching of the endophyte has been shown to be associated with a severe reduction of alkaloid production. Our results show that a plant-endophyte association in which increased branching occurs is still able to produce alkaloids. PMID:16769511

  12. Phytomonitoring of chlorinated ethenes in trees: a four-year study of seasonal chemodynamics in planta.

    PubMed

    Limmer, Matt A; Holmes, Amanda J; Burken, Joel G

    2014-09-16

    Long-term monitoring (LTM) of groundwater remedial projects is costly and time-consuming, particularly when using phytoremediation, a long-term remedial approach. The use of trees as sensors of groundwater contamination (i.e., phytoscreening) has been widely described, although the use of trees to provide long-term monitoring of such plumes (phytomonitoring) has been more limited due to unexplained variability of contaminant concentrations in trees. To assess this variability, we developed an in planta sampling method to obtain high-frequency measurements of chlorinated ethenes in oak (Quercus rubra) and baldcypress (Taxodium distichum) trees growing above a contaminated plume during a 4-year trial. The data set revealed that contaminant concentrations increased rapidly with transpiration in the spring and decreased in the fall, resulting in perchloroethene (PCE) and trichloroethene (TCE) sapwood concentrations an order of magnitude higher in late summer as compared to winter. Heartwood PCE and TCE concentrations were more buffered against seasonal effects. Rainfall events caused negligible dilution of contaminant concentrations in trees after precipitation events. Modeling evapotranspiration potential from meteorological data and comparing the modeled uptake and transport with the 4 years of high frequency data provides a foundation to advance the implementation of phytomonitoring and improved understanding of plant contaminant interactions. PMID:25140854

  13. Analysis of in planta Expressed Orphan Genes in the Rice Blast Fungus Magnaporthe oryzae

    PubMed Central

    Sadat, Abu; Jeon, Junhyun; Mir, Albely Afifa; Kim, Seongbeom; Choi, Jaeyoung; Lee, Yong-Hwan

    2014-01-01

    Genomes contain a large number of unique genes which have not been found in other species. Although the origin of such “orphan” genes remains unclear, they are thought to be involved in species-specific adaptive processes. Here, we analyzed seven orphan genes (MoSPC1 to MoSPC7) prioritized based on in planta expressed sequence tag data in the rice blast fungus, Magnaporthe oryzae. Expression analysis using qRT-PCR confirmed the expression of four genes (MoSPC1, MoSPC2, MoSPC3 and MoSPC7) during plant infection. However, individual deletion mutants of these four genes did not differ from the wild-type strain for all phenotypes examined, including pathogenicity. The length, GC contents, codon adaptation index and expression during mycelial growth of the four genes suggest that these genes formed during the evolutionary history of M. oryzae. Synteny analyses using closely related fungal species corroborated the notion that these genes evolved de novo in the M. oryzae genome. In this report, we discuss our inability to detect phenotypic changes in the four deletion mutants. Based on these results, the four orphan genes may be products of de novo gene birth processes, and their adaptive potential is in the course of being tested for retention or extinction through natural selection. PMID:25506301

  14. TYLCV-Is movement in planta does not require V2 protein

    SciTech Connect

    Hak, Hagit; Levy, Yael; Chandran, Sam A.; Belausov, Eduard; Loyter, Abraham; Lapidot, Moshe; Gafni, Yedidya

    2015-03-15

    Tomato yellow leaf curl virus (TYLCV), a major tomato pathogen causing extensive crop losses, is a whitefly-transmitted geminivirus. V2 mutants of TYLCV-Is and related viruses tend to induce symptomless infection with attenuated viral DNA levels, while accumulating close to wild-type DNA levels in protoplasts, suggesting V2 as a movement protein. The discovery of plant-silencing mechanisms and viral silencing suppressors, V2 included, led us to reconsider V2's involvement in viral movement. We studied two mutant versions of the virus, one impaired in V2 silencing-suppression activity, and another carrying a non-translatable V2. While both mutant viruses spread in the infected plant to newly emerged leaves at the same rate as the wild-type virus, their DNA-accumulation levels were tenfold lower than in the wild-type virus. Thus, we suggest that the setback in virus proliferation, previously ascribed to a movement impediment, is due to lack of silencing-suppression activity. - Highlights: • TYLCV-Is V2 protein is localized in distinct microbodies throughout the cell cytoplasm, around the nucleus and in association with cytoplasmic strands but is not associated with the plasmodesmata. • Disruption of RNA-silencing suppression activity of TYLCV-Is V2 protein causes low titer of the virus in the infected plants. • The movement of TYLCV-Is in planta does not require a functional V2 protein.

  15. Cytorhabdovirus P protein suppresses RISC-mediated cleavage and RNA silencing amplification in planta.

    PubMed

    Mann, Krin S; Johnson, Karyn N; Carroll, Bernard J; Dietzgen, Ralf G

    2016-03-01

    Plant viruses have evolved to undermine the RNA silencing pathway by expressing suppressor protein(s) that interfere with one or more key components of this antiviral defense. Here we show that the recently identified RNA silencing suppressor (RSS) of lettuce necrotic yellows virus (LNYV), phosphoprotein P, binds to RNA silencing machinery proteins AGO1, AGO2, AGO4, RDR6 and SGS3 in protein-protein interaction assays when transiently expressed. In planta, we demonstrate that LNYV P inhibits miRNA-guided AGO1 cleavage and translational repression, and RDR6/SGS3-dependent amplification of silencing. Analysis of LNYV P deletion mutants identified a C-terminal protein domain essential for both local RNA silencing suppression and interaction with AGO1, AGO2, AGO4, RDR6 and SGS3. In contrast to other viral RSS known to disrupt AGO activity, LNYV P sequence does not contain any recognizable GW/WG or F-box motifs. This suggests that LNYV P may represent a new class of AGO binding proteins. PMID:26808923

  16. Endophytic Colonization and In Planta Nitrogen Fixation by a Herbaspirillum sp. Isolated from Wild Rice Species

    PubMed Central

    Elbeltagy, Adel; Nishioka, Kiyo; Sato, Tadashi; Suzuki, Hisa; Ye, Bin; Hamada, Toru; Isawa, Tsuyoshi; Mitsui, Hisayuki; Minamisawa, Kiwamu

    2001-01-01

    Nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified Rennie medium. Based on 16S ribosomal DNA (rDNA) sequences, the diazotrophic isolates were phylogenetically close to four genera: Herbaspirillum, Ideonella, Enterobacter, and Azospirillum. Phenotypic properties and signature sequences of 16S rDNA indicated that three isolates (B65, B501, and B512) belong to the Herbaspirillum genus. To examine whether Herbaspirillum sp. strain B501 isolated from wild rice, Oryza officinalis, endophytically colonizes rice plants, the gfp gene encoding green fluorescent protein (GFP) was introduced into the bacteria. Observations by fluorescence stereomicroscopy showed that the GFP-tagged bacteria colonized shoots and seeds of aseptically grown seedlings of the original wild rice after inoculation of the seeds. Conversely, for cultivated rice Oryza sativa, no GFP fluorescence was observed for shoots and only weak signals were observed for seeds. Observations by fluorescence and electron microscopy revealed that Herbaspirillum sp. strain B501 colonized mainly intercellular spaces in the leaves of wild rice. Colony counts of surface-sterilized rice seedlings inoculated with the GFP-tagged bacteria indicated significantly more bacterial populations inside the original wild rice than in cultivated rice varieties. Moreover, after bacterial inoculation, in planta nitrogen fixation in young seedlings of wild rice, O. officinalis, was detected by the acetylene reduction and 15N2 gas incorporation assays. Therefore, we conclude that Herbaspirillum sp. strain B501 is a diazotrophic endophyte compatible with wild rice, particularly O. officinalis. PMID:11679357

  17. Advances in alfalfa mosaic virus-mediated expression of anthrax antigen in planta

    SciTech Connect

    Brodzik, R.; Bandurska, K.; Deka, D.; Golovkin, M.; Koprowski, H. . E-mail: h_koprowski@jefferson.edu

    2005-12-16

    Plant viruses show great potential for production of pharmaceuticals in plants. Such viruses can harbor a small antigenic peptide(s) as a part of their coat proteins (CP) and elicit an antigen-specific immune response. Here, we report the high yield and consistency in production of recombinant alfalfa mosaic virus (AlMV) particles for specific presentation of the small loop 15 amino acid epitope from domain-4 of the Bacillus anthracis protective antigen (PA-D4s). The epitope was inserted immediately after the first 25 N-terminal amino acids of AlMV CP to retain genome activation and binding of CP to viral RNAs. Recombinant AlMV particles were efficiently produced in tobacco, easily purified for immunological analysis, and exhibited extended stability and systemic proliferation in planta. Intraperitional injections of mice with recombinant plant virus particles harboring the PA-D4s epitope elicited a distinct immune response. Western blotting and ELISA analysis showed that sera from immunized mice recognized both native PA antigen and the AlMV CP.

  18. Development of 4-methoxy-7-nitroindolinyl (MNI)-caged auxins which are extremely stable in planta.

    PubMed

    Hayashi, Ken-Ichiro; Kusaka, Naoyuki; Yamasaki, Soma; Zhao, Yunde; Nozaki, Hiroshi

    2015-10-15

    Phytohormone auxin is a master regulator in plant growth and development. Regulation of cellular auxin level plays a central role in plant development. Auxin polar transport system modulates an auxin gradient that determines plant developmental process in response to environmental conditions and developmental programs. Photolabile caged auxins allow optical control of artificial auxin gradients at cellular resolution. Especially, two-photon uncaging system achieves high spatiotemporal control of photolysis reaction at two-photon cross-section. However, the development of caged versions of auxin has been limited by the instability of the caged auxins to higher plant metabolic activities. Here, we describe the synthesis and application of highly stable caged auxins, 4-methoxy-7-nitroindolinyl (MNI)-caged auxins. Natural auxin, indole 3-acetic acid, and two synthetic auxins, 1-NAA and 2,4-D were caged by MNI caging group. MNI-caged auxins showed a high stability in planta and a rapid release the original auxin when photolyzed. We demonstrated that optical control of auxin-responsive gene expression and auxin-related physiological responses by using MNI-caged auxins. We anticipate that MNI-caged auxins will be an effective tool for high-resolution control of endogenous auxin level. PMID:26364943

  19. Development of 4-methoxy-7-nitroindolinyl (MNI)-caged auxins which are extremely stable in planta

    PubMed Central

    Hayashi, Ken-ichiro; Kusaka, Naoyuki; Yamasaki, Soma; Zhao, Yunde; Nozaki, Hiroshi

    2015-01-01

    Phytohormone auxin is a master regulator in plant growth and development. Regulation of cellular auxin level plays a central role in plant development. Auxin polar transport system modulates an auxin gradient that determines plant developmental process in response to environmental conditions and developmental programs. Photolabile caged auxins allow optical control of artificial auxin gradients at cellular resolution. Especially, two-photon uncaging system achieves high spatiotemporal control of photolysis reaction at two-photon cross-section. However, the development of caged versions of auxin has been limited by the instability of the caged auxins to higher plant metabolic activities. Here, we describe the synthesis and application of highly stable caged auxins, 4-methoxy-7-nitroindolinyl (MNI)-caged auxins. Natural auxin, indole 3-acetic acid, and two synthetic auxins, 1-NAA and 2,4-D were caged by MNI caging group. MNI-caged auxins showed a high stability in planta and a rapid release the original auxin when photolyzed. We demonstrated that optical control of auxin-responsive gene expression and auxin-related physiological responses by using MNI-caged auxins. We anticipate that MNI-caged auxins will be an effective tool for high-resolution control of endogenous auxin level. PMID:26364943

  20. In planta selfing and oospore production of Phytophthora cinnamomi in the presence of Acacia pulchella.

    PubMed

    Jayasekera, Arunodini U; McComb, Jen A; Shearer, Bryan L; Hardy, Giles E St J

    2007-03-01

    This paper provides the first evidence of A2 type 1 and type 2 isolates of Phytophthora cinnamomi producing selfed oospores in planta in an Australian soil and in a potting mix. Oospores were observed in infected lupin (Lupinus angustifolius) roots incubated for 7d either in the substrate under potted Acacia pulchella plants, or in soils collected from under and near varieties of A. pulchella in jarrah (Eucalyptus marginata) forest. The A2 type isolates varied in their ability to produce selfed oospores and none were produced by A1 isolates. The gametangial association was amphigynous and spores were predominantly spherical with diameters from 13-40 microm. The oospores were viable but dormant. Two A2 type isolates produced small numbers of selfed oospores with amphigynous antheridia axenically in Ribeiro's liquid medium within 30 d, and one A2 type 2 isolate produced oospores after mating with an A1 strain. Evidence is presented that the presence of roots of Acacia pulchella, and particularly A. pulchella var. glaberrima and var. goadbyi, enhances the production of oospores. PMID:17350243

  1. Floral benzenoid carboxyl methyltransferases: From in vitro to in planta function

    PubMed Central

    Effmert, Uta; Saschenbrecker, Sandra; Ross, Jeannine; Negre, Florence; Fraser, Chris M.; Noel, Joseph P.; Dudareva, Natalia; Piechulla, Birgit

    2010-01-01

    Benzenoid carboxyl methyltransferases synthesize methyl esters (e.g., methyl benzoate and methyl salicylate), which are constituents of aromas and scents of many plant species and play important roles in plant communication with the surrounding environment. Within the past five years, eleven such carboxyl methyltransferases were isolated and most of them were comprehensively investigated at the biochemical, molecular and structural level. Two types of enzymes can be distinguished according to their substrate preferences: the SAMT-type enzymes isolated from Clarkia breweri, Stephanotis floribunda, Antirrhinum majus, Hoya carnosa, and Petunia hybrida, which have a higher catalytic efficiency and preference for salicylic acid, while BAMT-type enzymes from A. majus, Arabidopsis thaliana, Arabidopsis lyrata, and Nicotiana suaveolens prefer benzoic acid. The elucidation of C. breweri SAMT’s three-dimensional structure allowed a detailed modelling of the active sites of the carboxyl methyltransferases and revealed that the SAM binding pocket is highly conserved among these enzymes while the methyl acceptor binding site exhibits some variability, allowing a classification into SAMT-type and BAMT-type enzymes. The analysis of expression patterns coupled with biochemical characterization showed that these carboxyl methyltransferases are involved either in floral scent biosynthesis or in plant defense responses. While the latter can be induced by biotic or abiotic stress, the genes responsible for floral scent synthesis exhibit developmental and rhythmic expression pattern. The nature of the product and efficiency of its formation in planta depend on the availability of substrates, the catalytic efficiency of the enzyme toward benzoic acid and/or salicylic acid, and the transcriptional, translational, and post-translational regulation at the enzyme level. The biochemical properties of benzenoid carboxyl methyltransferases suggest that the genes involved in plant defenses might represent the ancestor for the presently existing floral genes which during evolution gained different expression profiles and encoded enzymes with the ability to accept structurally similar substrates. PMID:15946712

  2. 3D Domain Swapping Causes Extensive Multimerisation of Human Interleukin-10 When Expressed In Planta

    PubMed Central

    Roosien, Jan; van de Velde, Jan; Goverse, Aska; Bakker, Jaap; Schots, Arjen

    2012-01-01

    Heterologous expression platforms of biopharmaceutical proteins have been significantly improved over the last decade. Further improvement can be established by examining the intrinsic properties of proteins. Interleukin-10 (IL-10) is an anti-inflammatory cytokine with a short half-life that plays an important role in re-establishing immune homeostasis. This homodimeric protein of 36 kDa has significant therapeutic potential to treat inflammatory and autoimmune diseases. In this study we show that the major production bottleneck of human IL-10 is not protein instability as previously suggested, but extensive multimerisation due to its intrinsic 3D domain swapping characteristic. Extensive multimerisation of human IL-10 could be visualised as granules in planta. On the other hand, mouse IL-10 hardly multimerised, which could be largely attributed to its glycosylation. By introducing a short glycine-serine-linker between the fourth and fifth alpha helix of human IL-10 a stable monomeric form of IL-10 (hIL-10mono) was created that no longer multimerised and increased yield up to 20-fold. However, hIL-10mono no longer had the ability to reduce pro-inflammatory cytokine secretion from lipopolysaccharide-stimulated macrophages. Forcing dimerisation restored biological activity. This was achieved by fusing human IL-10mono to the C-terminal end of constant domains 2 and 3 of human immunoglobulin A (Fcα), a natural dimer. Stable dimeric forms of IL-10, like Fcα-IL-10, may not only be a better format for improved production, but also a more suitable format for medical applications. PMID:23049703

  3. In planta comparative transcriptomics of host-adapted strains of Ralstonia solanacearum

    PubMed Central

    Ailloud, Florent; Lowe, Tiffany M.; Robène, Isabelle; Cruveiller, Stéphane; Allen, Caitilyn

    2016-01-01

    Background. Ralstonia solanacearum is an economically important plant pathogen with an unusually large host range. The Moko (banana) and NPB (not pathogenic to banana) strain groups are closely related but are adapted to distinct hosts. Previous comparative genomics studies uncovered very few differences that could account for the host range difference between these pathotypes. To better understand the basis of this host specificity, we used RNAseq to profile the transcriptomes of an R. solanacearum Moko strain and an NPB strain under in vitro and in planta conditions. Results. RNAs were sequenced from bacteria grown in rich and minimal media, and from bacteria extracted from mid-stage infected tomato, banana and melon plants. We computed differential expression between each pair of conditions to identify constitutive and host-specific gene expression differences between Moko and NPB. We found that type III secreted effectors were globally up-regulated upon plant cell contact in the NPB strain compared with the Moko strain. Genes encoding siderophore biosynthesis and nitrogen assimilation genes were highly up-regulated in the NPB strain during melon pathogenesis, while denitrification genes were up-regulated in the Moko strain during banana pathogenesis. The relatively lower expression of oxidases and the denitrification pathway during banana pathogenesis suggests that R. solanacearum experiences higher oxygen levels in banana pseudostems than in tomato or melon xylem. Conclusions. This study provides the first report of differential gene expression associated with host range variation. Despite minimal genomic divergence, the pathogenesis of Moko and NPB strains is characterized by striking differences in expression of virulence- and metabolism-related genes. PMID:26788428

  4. Barley RIC171 interacts with RACB in planta and supports entry of the powdery mildew fungus.

    PubMed

    Schultheiss, Holger; Preuss, Jutta; Pircher, Thomas; Eichmann, Ruth; Hückelhoven, Ralph

    2008-09-01

    RHO-like GTPases of plants (ROPs, also called RACs) are involved in plant development and interaction with the environment. The barley ROP protein RACB is involved in susceptibility to the fungal pathogen Blumeria graminis f.sp. hordei (Bgh). By screening barley sequence databases for potential protein interactors of plant RHO-like proteins, we identified a ROP-interactive CRIB (CDC42/RAC interactive binding) motif containing protein of 171 amino acids (RIC171). The protein interacted with constitutively activated RACB in a targeted yeast two-hybrid assay. By use of split yellow fluorescing protein fusions, we demonstrated that RIC171 interacts with constitutively activated (CA) RACB-G15V but not with dominant negative RACB-T20N in planta. Transient overexpression of RIC171, similar to overexpression of CA RACB-G15V, rendered epidermal cells more susceptible to penetration by Bgh. In contrast, expression of a 46-amino-acid RIC171-CRIB peptide, which was sufficient to interact with CA RACB-G15V, had a dominant negative effect and reduced susceptibility to Bgh. A red fluorescing DsRED-RIC171 fusion protein colocalized with green fluorescing GFP-RACB-G15V at the cell periphery. Coexpression with CA RACB-G15V but not with RACB-T20N increased peripheral localization of DsRED-RIC171. Additionally, DsRED-RIC171 accumulated at sites of fungal attack, suggesting enhanced ROP activity at sites of attempted fungal penetration. PMID:18466344

  5. Bioinspired engineering study of Plantae vascules for self-healing composite structures

    PubMed Central

    Trask, R. S.; Bond, I. P.

    2010-01-01

    This paper presents the first conceptual study into creating a Plantae-inspired vascular network within a fibre-reinforced polymer composite laminate, which provides an ongoing self-healing functionality without incurring a mass penalty. Through the application of a ‘lost-wax’ technique, orthogonal hollow vascules, inspired by the ‘ray cell’ structures found in ring porous hardwoods, were successfully introduced within a carbon fibre-reinforced epoxy polymer composite laminate. The influence on fibre architecture and mechanical behaviour of single vascules (located on the laminate centreline) when aligned parallel and transverse to the local host ply was characterized experimentally using a compression-after-impact test methodology. Ultrasonic C-scanning and high-resolution micro-CT X-ray was undertaken to identify the influence of and interaction between the internal vasculature and impact damage. The results clearly show that damage morphology is influenced by vascule orientation and that a 10 J low-velocity impact damage event is sufficient to breach the vasculature; a prerequisite for any subsequent self-healing function. The residual compressive strength after a 10 J impact was found to be dependent upon vascule orientation. In general, residual compressive strength decreased to 70 per cent of undamaged strength when vasculature was aligned parallel to the local host ply and a value of 63 per cent when aligned transverse. This bioinspired engineering study has illustrated the potential that a vasculature concept has to offer in terms of providing a self-healing function with minimum mass penalty, without initiating premature failure within a composite structure. PMID:19955122

  6. The In Planta Transcriptome of Ralstonia solanacearum: Conserved Physiological and Virulence Strategies during Bacterial Wilt of Tomato

    PubMed Central

    Jacobs, Jonathan M.; Babujee, Lavanya; Meng, Fanhong; Milling, Annett; Allen, Caitilyn

    2012-01-01

    ABSTRACT Plant xylem fluid is considered a nutrient-poor environment, but the bacterial wilt pathogen Ralstonia solanacearum is well adapted to it, growing to 108 to 109 CFU/g tomato stem. To better understand how R. solanacearum succeeds in this habitat, we analyzed the transcriptomes of two phylogenetically distinct R. solanacearum strains that both wilt tomato, strains UW551 (phylotype II) and GMI1000 (phylotype I). We profiled bacterial gene expression at ~6 × 108 CFU/ml in culture or in plant xylem during early tomato bacterial wilt pathogenesis. Despite phylogenetic differences, these two strains expressed their 3,477 common orthologous genes in generally similar patterns, with about 12% of their transcriptomes significantly altered in planta versus in rich medium. Several primary metabolic pathways were highly expressed during pathogenesis. These pathways included sucrose uptake and catabolism, and components of these pathways were encoded by genes in the scrABY cluster. A UW551 scrA mutant was significantly reduced in virulence on resistant and susceptible tomato as well as on potato and the epidemiologically important weed host Solanum dulcamara. Functional scrA contributed to pathogen competitive fitness during colonization of tomato xylem, which contained ~300 µM sucrose. scrA expression was induced by sucrose, but to a much greater degree by growth in planta. Unexpectedly, 45% of the genes directly regulated by HrpB, the transcriptional activator of the type 3 secretion system (T3SS), were upregulated in planta at high cell densities. This result modifies a regulatory model based on bacterial behavior in culture, where this key virulence factor is repressed at high cell densities. The active transcription of these genes in wilting plants suggests that T3SS has a biological role throughout the disease cycle. PMID:22807564

  7. Nodularin, a cyanobacterial toxin, is synthesized in planta by symbiotic Nostoc sp.

    PubMed Central

    Gehringer, Michelle M; Adler, Lewis; Roberts, Alexandra A; Moffitt, Michelle C; Mihali, Troco K; Mills, Toby J T; Fieker, Claus; Neilan, Brett A

    2012-01-01

    The nitrogen-fixing bacterium, Nostoc, is a commonly occurring cyanobacterium often found in symbiotic associations. We investigated the potential of cycad cyanobacterial endosymbionts to synthesize microcystin/nodularin. Endosymbiont DNA was screened for the aminotransferase domain of the toxin biosynthesis gene clusters. Five endosymbionts carrying the gene were screened for bioactivity. Extracts of two isolates inhibited protein phosphatase 2A and were further analyzed using electrospray ionization mass spectrometry (ESI-MS)/MS. Nostoc sp. ‘Macrozamia riedlei 65.1' and Nostoc sp. ‘Macrozamia serpentina 73.1' both contained nodularin. High performance liquid chromatography (HPLC) HESI-MS/MS analysis confirmed the presence of nodularin at 9.55±2.4 ng μg−1 chlorophyll a in Nostoc sp. ‘Macrozamia riedlei 65.1' and 12.5±8.4 ng μg−1 Chl a in Nostoc sp. ‘Macrozamia serpentina 73.1' extracts. Further scans indicated the presence of the rare isoform [L-Har2] nodularin, which contains ℒ-homoarginine instead of ℒ-arginine. Nodularin was also present at 1.34±0.74 ng ml−1 (approximately 3 pmol per g plant ww) in the methanol root extracts of M. riedlei MZ65, while the presence of [L-Har2] nodularin in the roots of M. serpentina MZ73 was suggested by HPLC HESI-MS/MS analysis. The ndaA-B and ndaF genomic regions were sequenced to confirm the presence of the hybrid polyketide/non-ribosomal gene cluster. A seven amino-acid insertion into the NdaA-C1 domain of N. spumigena NSOR10 protein was observed in all endosymbiont-derived sequences, suggesting the transfer of the nda cluster from N. spumigena to terrestrial Nostoc species. This study demonstrates the synthesis of nodularin and [L-Har2] nodularin in a non-Nodularia species and the production of cyanobacterial hepatotoxin by a symbiont in planta. PMID:22456448

  8. Nodularin, a cyanobacterial toxin, is synthesized in planta by symbiotic Nostoc sp.

    PubMed

    Gehringer, Michelle M; Adler, Lewis; Roberts, Alexandra A; Moffitt, Michelle C; Mihali, Troco K; Mills, Toby J T; Fieker, Claus; Neilan, Brett A

    2012-10-01

    The nitrogen-fixing bacterium, Nostoc, is a commonly occurring cyanobacterium often found in symbiotic associations. We investigated the potential of cycad cyanobacterial endosymbionts to synthesize microcystin/nodularin. Endosymbiont DNA was screened for the aminotransferase domain of the toxin biosynthesis gene clusters. Five endosymbionts carrying the gene were screened for bioactivity. Extracts of two isolates inhibited protein phosphatase 2A and were further analyzed using electrospray ionization mass spectrometry (ESI-MS)/MS. Nostoc sp. 'Macrozamia riedlei 65.1' and Nostoc sp. 'Macrozamia serpentina 73.1' both contained nodularin. High performance liquid chromatography (HPLC) HESI-MS/MS analysis confirmed the presence of nodularin at 9.55±2.4 ng μg-1 chlorophyll a in Nostoc sp. 'Macrozamia riedlei 65.1' and 12.5±8.4 ng μg-1 Chl a in Nostoc sp. 'Macrozamia serpentina 73.1' extracts. Further scans indicated the presence of the rare isoform [L-Har(2)] nodularin, which contains L-homoarginine instead of L-arginine. Nodularin was also present at 1.34±0.74 ng ml(-1) (approximately 3 pmol per g plant ww) in the methanol root extracts of M. riedlei MZ65, while the presence of [L-Har(2)] nodularin in the roots of M. serpentina MZ73 was suggested by HPLC HESI-MS/MS analysis. The ndaA-B and ndaF genomic regions were sequenced to confirm the presence of the hybrid polyketide/non-ribosomal gene cluster. A seven amino-acid insertion into the NdaA-C1 domain of N. spumigena NSOR10 protein was observed in all endosymbiont-derived sequences, suggesting the transfer of the nda cluster from N. spumigena to terrestrial Nostoc species. This study demonstrates the synthesis of nodularin and [L-Har(2)] nodularin in a non-Nodularia species and the production of cyanobacterial hepatotoxin by a symbiont in planta. PMID:22456448

  9. In planta gene expression analysis of Xanthomonas oryzae pathovar oryzae, African strain MAI1

    PubMed Central

    2010-01-01

    Background Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo), induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc). Results Changes in gene expression of the African Xoo strain MAI1 in the susceptible rice cultivar Nipponbare were profiled, using an SSH Xoo DNA microarray. Microarray hybridization was performed comparing bacteria recovered from plant tissues at 1, 3, and 6 days after inoculation (dai) with bacteria grown in vitro. A total of 710 bacterial genes were found to be differentially expressed, with 407 up-regulated and 303 down-regulated. Expression profiling indicated that less than 20% of the 710 bacterial transcripts were induced in the first 24 h after inoculation, whereas 63% were differentially expressed at 6 dai. The 710 differentially expressed genes were one-end sequenced. 535 sequences were obtained from which 147 non-redundant sequences were identified. Differentially expressed genes were related to metabolism, secretion and transport, pathogen adherence to plant tissues, plant cell-wall degradation, IS elements, and virulence. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. The Xoo MAI1 non-redundant set of sequences was compared against several X. oryzae genomes, revealing a specific group of genes that was present only in MAI1. Numerous IS elements were also found to be differentially expressed. Quantitative real-time PCR confirmed 86% of the identified profile on a set of 14 genes selected according to the microarray analysis. Conclusions This is the first report to compare the expression of Xoo genes in planta across different time points during infection. This work shows that as-yet-unidentified and potentially new virulence factors are appearing in an emerging African pathogen. It also confirms that African Xoo strains do differ from their Asian counterparts, even at the transcriptional level. PMID:20540733

  10. In-planta sporulation phenotype: a major life history trait to understand the evolution of Alnus-infective Frankia strains.

    PubMed

    Pozzi, Adrien C; Bautista-Guerrero, Hector H; Nouioui, Imen; Cotin-Galvan, Laëtitia; Pepin, Régis; Fournier, Pascale; Menu, Frédéric; Fernandez, Maria P; Herrera-Belaroussi, Aude

    2015-09-01

    Two major types of Frankia strains are usually recognized, based on the ability to sporulate in-planta: spore-positive (Sp+) and spore-negative (Sp-). We carried out a study of Sp+ and Sp- Frankia strains based on nodules collected on Alnus glutinosa, Alnus incana and Alnus viridis. The nodules were phenotyped using improved histology methods, and endophytic Frankia strain genotype was determined using a multilocus sequence analysis approach. An additional sampling was done to assess the relation between Sp+ phenotype frequency and genetic diversity of Frankia strains at the alder stand scale. Our results revealed that (i) Sp+ and Sp- Alnus-infective Frankia strains are genetically different even when sampled from the same alder stand and the same host-plant species; (ii) there are at least two distinct phylogenetic lineages of Sp+ Frankia that cluster according to the host-plant species and without regard of geographic distance and (iii) genetic diversity of Sp+ strains is very low at the alder stand scale compared with Sp- strains. Difference in evolutionary history and genetic diversity between Sp+ and Sp- Frankia allows us to discuss the possible ecological role of in-planta sporulation. PMID:25335453

  11. Comparaison entre deux logiciels d'analyse optique

    NASA Astrophysics Data System (ADS)

    Le Gall, J. Y.; Iorio-Fili, D.; Bertani, D.; Cetica, M.; Lusito, A.

    Les auteurs prsentent une tude comparative entre les deux logiciels d'analyse optique qui ont t dvelopps l'INO (Florence) et au LAS (Marseille). Les objectifs, les techniques utilises et les caractristiques sont exposs. On conclue en montrant la complmentarit de ces travaux.

  12. Unfolding of in planta activity of anti-rep ribozyme in presence of a RNA silencing suppressor.

    PubMed

    Mishra, Sumona Karjee; Chilakamarthi, Ushasri; Deb, J K; Mukherjee, Sunil Kumar

    2014-05-21

    Antisense RNA ribozymes have intrinsic endonucleolytic activity to effect cleavage of the target RNA. However, this activity in vivo is often controlled by the dominance of antisense or other double-stranded RNA mechanism. In this work, we demonstrate the in planta activity of a hammerhead ribozyme designed to target rep-mRNA of a phytopathogen Mungbean Yellow Mosaic India virus (MYMIV) as an antiviral agent. We also found RNA-silencing is induced on introduction of catalytically active as well as inactive ribozymes. Using RNA-silencing suppressors (RSS), we demonstrate that the endonucleolytic activity of ribozymes is a true phenomenon, even while a mutated version may demonstrate a similar down-regulation of the target RNA. This helps to ease the confusion over the action mechanism of ribozymes in vivo. PMID:24735726

  13. In planta expression of A. cellulolyticus Cel5A endocellulase reduces cell wall recalcitrance in tobacco and maize

    PubMed Central

    2011-01-01

    The glycoside hydrolase family 5 endocellulase, E1 (Cel5A), from Acidothermus cellulolyticus was transformed into both Nicotiana tabacum and Zea mays with expression targeted to the cell wall under a constitutive promoter. Here we explore the possibility that in planta expression of endocellulases will allow these enzymes to access their substrates during cell wall construction, rendering cellulose more amenable to pretreatment and enzyme digestion. Tobacco and maize plants were healthy and developed normally compared with the wild type (WT). After thermochemical pretreatment and enzyme digestion, transformed plants were clearly more digestible than WT, requiring lower pretreatment severity to achieve comparable conversion levels. Furthermore, the decreased recalcitrance was not due to post-pretreatment residual E1 activity and could not be reproduced by the addition of exogenous E1 to the biomass prior to pretreatment, indicating that the expression of E1 during cell wall construction altered the inherent recalcitrance of the cell wall. PMID:21269444

  14. The small subunit of snapdragon geranyl diphosphate synthase modifies the chain length specificity of tobacco geranylgeranyl diphosphate synthase in planta.

    PubMed

    Orlova, Irina; Nagegowda, Dinesh A; Kish, Christine M; Gutensohn, Michael; Maeda, Hiroshi; Varbanova, Marina; Fridman, Eyal; Yamaguchi, Shinjiro; Hanada, Atsushi; Kamiya, Yuji; Krichevsky, Alexander; Citovsky, Vitaly; Pichersky, Eran; Dudareva, Natalia

    2009-12-01

    Geranyl diphosphate (GPP), the precursor of many monoterpene end products, is synthesized in plastids by a condensation of dimethylallyl diphosphate and isopentenyl diphosphate (IPP) in a reaction catalyzed by homodimeric or heterodimeric GPP synthase (GPPS). In the heterodimeric enzymes, a noncatalytic small subunit (GPPS.SSU) determines the product specificity of the catalytic large subunit, which may be either an active geranylgeranyl diphosphate synthase (GGPPS) or an inactive GGPPS-like protein. Here, we show that expression of snapdragon (Antirrhinum majus) GPPS.SSU in tobacco (Nicotiana tabacum) plants increased the total GPPS activity and monoterpene emission from leaves and flowers, indicating that the introduced catalytically inactive GPPS.SSU found endogenous large subunit partner(s) and formed an active snapdragon/tobacco GPPS in planta. Bimolecular fluorescence complementation and in vitro enzyme analysis of individual and hybrid proteins revealed that two of four GGPPS-like candidates from tobacco EST databases encode bona fide GGPPS that can interact with snapdragon GPPS.SSU and form a functional GPPS enzyme in plastids. The formation of chimeric GPPS in transgenic plants also resulted in leaf chlorosis, increased light sensitivity, and dwarfism due to decreased levels of chlorophylls, carotenoids, and gibberellins. In addition, these transgenic plants had reduced levels of sesquiterpene emission, suggesting that the export of isoprenoid intermediates from the plastids into the cytosol was decreased. These results provide genetic evidence that GPPS.SSU modifies the chain length specificity of phylogenetically distant GGPPS and can modulate IPP flux distribution between GPP and GGPP synthesis in planta. PMID:20028839

  15. Development of fiber optic spectroscopy for in-vitro and in-planta detection of fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Liew, Oi Wah; Chen, Jun-Wei; Asundi, Anand K.

    2001-10-01

    The objective of this project is to apply photonics technology to bio-safety management of genetically modified (GM) plants. The conventional method for screening GM plants is through selection using antibiotic resistance markers. There is public concern with such approaches and these are associated with food safety issues, escape of antibiotic resistance genes to pathogenic microorganisms and interference with antibiotic therapy. Thus, the strategy taken in this project is to replace antibiotic resistance markers with fluorescent protein markers that allow for rapid and non-invasive optical screening of genetically modified plants. In this paper, fibre optic spectroscopy was developed to detect and quantify recombinant green (EGFP) and red (DsRED) fluorescent proteins in vitro and in planta. In vitro detection was first carried out to optimize the sensitivity of the optical system. The bacterial expression vectors carrying the coding regions of EGFP and DsRED were introduced into Escherichia coli host cells and fluorescent proteins were produced following induction with IPTG. Soluble EGFP and DsRED proteins were isolated from lysed bacterial cells and serially diluted for quantitative analysis by fibre optic spectroscopy using different light sources, namely, blue LED (475 nm), tungsten halogen (350 - 1000 nm) and double frequency Nd:YAG green laser (532 nm). Fluorescence near the expected emission wavelengths could be detected up to 320X dilution for EGFP and DsRED with blue LED and 532 nm green laser, respectively, as the excitation source. Tungsten halogen was found to be unsuitable for excitation of both EGFP and DsRED. EGFP was successfully purified by size separation under non-denaturing electrophoretic conditions and quantified. The minimum concentration of EGFP detectable with blue LED excitation was 5 mg/ml. To determine the capability of spectroscopy detection in planta, transgenic potato hairy roots and whole modified plant lines expressing the fluorescent markers were regenerated. T

  16. Phytohormonal Networks Promote Differentiation of Fiber Initials on Pre-Anthesis Cotton Ovules Grown In Vitro and In Planta

    PubMed Central

    Kim, Hee Jin; Hinchliffe, Doug J.; Triplett, Barbara A.; Chen, Z. Jeffrey; Stelly, David M.; Yeater, Kathleen M.; Moon, Hong S.; Gilbert, Matthew K.; Thyssen, Gregory N.; Turley, Rickie B.; Fang, David D.

    2015-01-01

    The number of cotton (Gossypium sp.) ovule epidermal cells differentiating into fiber initials is an important factor affecting cotton yield and fiber quality. Despite extensive efforts in determining the molecular mechanisms regulating fiber initial differentiation, only a few genes responsible for fiber initial differentiation have been discovered. To identify putative genes directly involved in the fiber initiation process, we used a cotton ovule culture technique that controls the timing of fiber initial differentiation by exogenous phytohormone application in combination with comparative expression analyses between wild type and three fiberless mutants. The addition of exogenous auxin and gibberellins to pre-anthesis wild type ovules that did not have visible fiber initials increased the expression of genes affecting auxin, ethylene, ABA and jasmonic acid signaling pathways within 1 h after treatment. Most transcripts expressed differentially by the phytohormone treatment in vitro were also differentially expressed in the ovules of wild type and fiberless mutants that were grown in planta. In addition to MYB25-like, a gene that was previously shown to be associated with the differentiation of fiber initials, several other differentially expressed genes, including auxin/indole-3-acetic acid (AUX/IAA) involved in auxin signaling, ACC oxidase involved in ethylene biosynthesis, and abscisic acid (ABA) 8'-hydroxylase an enzyme that controls the rate of ABA catabolism, were co-regulated in the pre-anthesis ovules of both wild type and fiberless mutants. These results support the hypothesis that phytohormonal signaling networks regulate the temporal expression of genes responsible for differentiation of cotton fiber initials in vitro and in planta. PMID:25927364

  17. Astronomy at School: Measurements of the Earth-Moon Distance. (Spanish Title: Astronomía en la Escuela: Medición de la Distancia Tierra-Luna.) Astronomia na Escola: Medida da Distância Terra-Lua

    NASA Astrophysics Data System (ADS)

    Paolantonio, Santiago; Pintado, Olga I.

    2006-12-01

    The aim of this project is to approach High School students to Science. We propose to measure the Earth-Moon distance using the parallax. The observation and measurements techniques and all the calculations needed are described in this paper. The results obtained in a test experience realized during 2003 are presented. This test shows that this is a feasible project and also shows which things needed to be improved. Se plantea la propuesta de un proyecto educativo dirigido al Nivel Medio de enseñanza, consistente en la determinación de la distancia Tierra - Luna por paralaje. Se describen las técnicas de observación, mediciones y cálculos. Se proporcionan a continuación los resultados obtenidos en la experiencia piloto realizada en el 2003, la que permitió comprobar la factibilidad de llevar a cabo la propuesta, así como perfeccionar los diferentes aspectos involucrados en la misma. Propomos neste trabalho um projeto educativo dirigido ao Ensino Médio que consiste na determinação da distância Terra-Lua pelo efeito da paralaxe. As técnicas de observação, medidas e cálculos auxiliares são descritos, e os resultados obtidos numa experiência-teste realizada no ano de 2003 apresentados. Este último teste permitiu comprovar a viabilidade de execução da proposta e aperfeiçoar diversos aspectos da mesma.

  18. Functional characterisation of metal(loid) processes in planta through the integration of synchrotron techniques and plant molecular biology

    PubMed Central

    Donner, Erica; Punshon, Tracy; Guerinot, Mary Lou; Lombi, Enzo

    2013-01-01

    Functional characterisation of the genes regulating metal(loid) homeostasis in plants is a major focus of crop biofortification, phytoremediation, and food security research. This paper focuses on the potential for advancing plant metal(loid) research by combining molecular biology and synchrotron-based techniques. Recent advances in x-ray focussing optics and fluorescence detection have greatly improved the potential of synchrotron techniques for plant science research, allowing metal(loids) to be imaged in vivo in hydrated plant tissues at sub-micron resolution. Laterally resolved metal(loid) speciation can also be determined. By using molecular techniques to probe the location of gene expression and protein localisation and combining it with this synchrotron-derived data, functional information can be effectively and efficiently assigned to specific genes. This paper provides a review of the state of the art in this field, and provides examples as to how synchrotron-based methods can be combined with molecular techniques to facilitate functional characterisation of genes in planta. PMID:22200921

  19. Monitoring in planta bacterial infection at both cellular and whole-plant levels using the green fluorescent protein variant GFPuv.

    PubMed

    Wang, Keri; Kang, Li; Anand, Ajith; Lazarovits, George; Mysore, Kirankumar S

    2007-01-01

    * Green fluorescent protein (GFP) labeling of bacteria has been used to study their infection of and localization in plants, but strong autofluorescence from leaves and the relatively weak green fluorescence of GFP-labeled bacteria restrict its broader application to investigations of plant-bacterial interactions. * A stable and broad-host-range plasmid vector (pDSK-GFPuv) that strongly expresses GFPuv protein was constructed not only for in vivo monitoring of bacterial infection, localization, activity, and movement at the cellular level under fluorescence microscopy, but also for monitoring bacterial disease development at the whole-plant level under long-wavelength ultraviolet (UV) light. * The presence of pDSK-GFPuv did not have significant impact on the in vitro or in planta growth and virulence of phytobacteria. A good correlation between bacterial cell number and fluorescence intensity was observed, which allowed us to rapidly estimate the bacterial population in plant leaf tissue. We demonstrated that GFPuv-expressing bacteria can be used to screen plants that are compromised for nonhost disease resistance and Agrobacterium attachment. * The use of GFPuv-labeled bacteria has a wide range of applications in host-bacterial interaction studies and bacterial ecology-related research. PMID:17335510

  20. A toolset of aequorin expression vectors for in planta studies of subcellular calcium concentrations in Arabidopsis thaliana.

    PubMed

    Mehlmer, Norbert; Parvin, Nargis; Hurst, Charlotte H; Knight, Marc R; Teige, Markus; Vothknecht, Ute C

    2012-02-01

    Calcium has long been acknowledged as one of the most important signalling components in plants. Many abiotic and biotic stimuli are transduced into a cellular response by temporal and spatial changes in cellular calcium concentration and the calcium-sensitive protein aequorin has been exploited as a genetically encoded calcium indicator for the measurement of calcium in planta. The objective of this work was to generate a compatible set of aequorin expression plasmids for the generation of transgenic plant lines to measure changes in calcium levels in different cellular subcompartments. Aequorin was fused to different targeting peptides or organellar proteins as a means to localize it to the cytosol, the nucleus, the plasma membrane, and the mitochondria. Furthermore, constructs were designed to localize aequorin in the stroma as well as the inner and outer surface of the chloroplast envelope membranes. The modular set-up of the plasmids also allows the easy replacement of targeting sequences to include other compartments. An additional YFP-fusion was included to verify the correct subcellular localization of all constructs by laser scanning confocal microscopy. For each construct, pBin19-based binary expression vectors driven by the 35S or UBI10 promoter were made for Agrobacterium-mediated transformation. Stable Arabidopsis lines were generated and initial tests of several lines confirmed their feasibility to measure calcium signals in vivo. PMID:22213817

  1. A toolset of aequorin expression vectors for in planta studies of subcellular calcium concentrations in Arabidopsis thaliana

    PubMed Central

    Mehlmer, Norbert; Parvin, Nargis; Hurst, Charlotte H.; Knight, Marc R.; Teige, Markus; Vothknecht, Ute C.

    2014-01-01

    Calcium has long been acknowledged as one of the most important signalling components in plants. Many abiotic and biotic stimuli are transduced into a cellular response by temporal and spatial changes in cellular calcium concentration and the calcium-sensitive protein aequorin has been exploited as a genetically encoded calcium indicator for the measurement of calcium in planta. The objective of this work was to generate a compatible set of aequorin expression plasmids for the generation of transgenic plant lines to measure changes in calcium levels in different cellular subcompartments. Aequorin was fused to different targeting peptides or organellar proteins as a means to localize it to the cytosol, the nucleus, the plasma membrane, and the mitochondria. Furthermore, constructs were designed to localize aequorin in the stroma as well as the inner and outer surface of the chloroplast envelope membranes. The modular set-up of the plasmids also allows the easy replacement of targeting sequences to include other compartments. An additional YFP-fusion was included to verify the correct subcellular localization of all constructs by laser scanning confocal microscopy. For each construct, pBin19-based binary expression vectors driven by the 35S or UBI10 promoter were made for Agrobacterium-mediated transformation. Stable Arabidopsis lines were generated and initial tests of several lines confirmed their feasibility to measure calcium signals in vivo. PMID:22213817

  2. Sucrose phosphate synthase and sucrose phosphate phosphatase interact in planta and promote plant growth and biomass accumulation.

    PubMed

    Maloney, Victoria J; Park, Ji-Young; Unda, Faride; Mansfield, Shawn D

    2015-07-01

    Bioinformatic analysis indicates that sucrose phosphate synthase (SPS) contains a putative C-terminal sucrose phosphate phosphatase (SPP)-like domain that may facilitates the binding of SPP. If an SPS-SPP enzyme complex exists, it may provide sucrose biosynthesis with an additional level of regulation, forming a direct metabolic channel for sucrose-6-phosphate between these two enzymes. Herein, the formation of an enzyme complex between SPS and SPP was examined, and the results from yeast two-hybrid experiments suggest that there is indeed an association between these proteins. In addition, in planta bioluminescence resonance energy transfer (BRET) was observed in Arabidopsis seedlings, providing physical evidence for a protein interaction in live cells and in real time. Finally, bimolecular fluorescence complementation (BiFC) was employed in an attempt to detect SPS-SPP interactions visually. The findings clearly demonstrated that SPS interacts with SPP and that this interaction impacts soluble carbohydrate pools and affects carbon partitioning to starch. Moreover, a fusion construct between the two genes promotes plant growth in both transgenic Arabidopsis and hybrid poplar. PMID:25873678

  3. In planta mechanism of action of leptospermone: impact of its physico-chemical properties on uptake, translocation, and metabolism.

    PubMed

    Owens, Daniel K; Nanayakkara, N P Dhammika; Dayan, Franck E

    2013-02-01

    Leptospermone is a natural β-triketone that specifically inhibits the enzyme p-hydrophyphenylpyruvate dioxygenase, the same molecular target site as that of the commercial herbicide mesotrione. The β-triketone-rich essential oil of Leptospermum scoparium has both preemergence and postemergence herbicidal activity, resulting in bleaching of treated plants and dramatic growth reduction. Radiolabeled leptospermone was synthesized to investigate the in planta mechanism of action of this natural herbicide. Approximately 50 % of the absorbed leptospermone was translocated to the foliage suggesting rapid acropetal movement of the molecule. On the other hand, very little leptospermone was translocated away from the point of application on the foliage, indicating poor phloem mobility. These observations are consistent with the physico-chemical properties of leptospermone, such as its experimentally measured logP and pK a values, and molecular mass, number of hydrogen donors and acceptors, and number of rotatable bonds. Consequently, leptospermone is taken up readily by roots and translocated to reach its molecular target site. This provides additional evidence that the anecdotal observation of allelopathic suppression of plant growth under β-triketone-producing species may be due to the release of these phytotoxins in soils. PMID:23314892

  4. In planta transformation of sorghum (Sorghum bicolor (L.) Moench) using TPS1 gene for enhancing tolerance to abiotic stresses.

    PubMed

    Yellisetty, Varalaxmi; Reddy, L A; Mandapaka, Maheswari

    2015-09-01

    An in planta transformation protocol for sorghum (Sorghum bicolor (L.) Moench) using shoot apical meristem of germinating seedlings is reported in this study. Agrobacterium tumefaciens strain, LBA4404 with pCAMBIA1303 vector and construct pCAMBIA1303TPS1 were individually used for transformation. Since, the transgene is integrated into the cells of already differentiated tissues, the T 0 plants were chimeric and stable integration was observed in T1 generation. β-Glucuronidase (GUS) expression in the seedlings and spikelets of emerging cob was the first indication of transformability in T0 generation which was further confirmed by PCR analysis using hpt and TPS1 gene-specific primers. Screening on 25 mg/L hygromycin combined with PCR analysis was used for selection of transformants in the T1 generation. Transformation efficiencies ranged between 34-38% and 26-34% using pCAMBIA1303 vector and construct pCAMBIA1303TPS1, respectively. Molecular characterization of the T2 transgenics using PCR, RT-PCR and Southern blot analyses further revealed the integration, expression and inheritance of the transgene. These results indicate the feasibility of the method to generate transgenics with pCAM-BIA1303 vector and construct pCAMBIA1303TPS1. The abiotic stress tolerance of TPS1 transgenics developed in the present study was evident by the ability of the transformants to tolerate 200 mM NaCl as well as higher root growth and biomass. PMID:26440081

  5. Agrobacterium tumefaciens Deploys a Superfamily of Type VI Secretion DNase Effectors as Weapons for Interbacterial Competition In Planta

    PubMed Central

    Ma, Lay-Sun; Hachani, Abderrahman; Lin, Jer-Sheng; Filloux, Alain; Lai, Erh-Min

    2014-01-01

    Summary The type VI secretion system (T6SS) is a widespread molecular weapon deployed by many Proteobacteria to target effectors/toxins into both eukaryotic and prokaryotic cells. We report that Agrobacterium tumefaciens, a soil bacterium that triggers tumorigenesis in plants, produces a family of type VI DNase effectors (Tde) that are distinct from previously known polymorphic toxins and nucleases. Tde exhibits an antibacterial DNase activity that relies on a conserved HxxD motif and can be counteracted by a cognate immunity protein, Tdi. In vitro, A. tumefaciens T6SS could kill Escherichia coli but triggered a lethal counterattack by Pseudomonas aeruginosa upon injection of the Tde toxins. However, in an in planta coinfection assay, A. tumefaciens used Tde effectors to attack both siblings cells and P. aeruginosa to ultimately gain a competitive advantage. Such acquired T6SS-dependent fitness in vivo and conservation of Tde-Tdi couples in bacteria highlights a widespread antibacterial weapon beneficial for niche colonization. PMID:24981331

  6. Sucrose phosphate synthase and sucrose phosphate phosphatase interact in planta and promote plant growth and biomass accumulation

    PubMed Central

    Maloney, Victoria J.; Park, Ji-Young; Unda, Faride; Mansfield, Shawn D.

    2015-01-01

    Bioinformatic analysis indicates that sucrose phosphate synthase (SPS) contains a putative C-terminal sucrose phosphate phosphatase (SPP)-like domain that may facilitates the binding of SPP. If an SPS–SPP enzyme complex exists, it may provide sucrose biosynthesis with an additional level of regulation, forming a direct metabolic channel for sucrose-6-phosphate between these two enzymes. Herein, the formation of an enzyme complex between SPS and SPP was examined, and the results from yeast two-hybrid experiments suggest that there is indeed an association between these proteins. In addition, in planta bioluminescence resonance energy transfer (BRET) was observed in Arabidopsis seedlings, providing physical evidence for a protein interaction in live cells and in real time. Finally, bimolecular fluorescence complementation (BiFC) was employed in an attempt to detect SPS–SPP interactions visually. The findings clearly demonstrated that SPS interacts with SPP and that this interaction impacts soluble carbohydrate pools and affects carbon partitioning to starch. Moreover, a fusion construct between the two genes promotes plant growth in both transgenic Arabidopsis and hybrid poplar. PMID:25873678

  7. The maternal chromosome set is the target of the T-DNA in the in planta transformation of Arabidopsis thaliana.

    PubMed Central

    Bechtold, N; Jaudeau, B; Jolivet, S; Maba, B; Vezon, D; Voisin, R; Pelletier, G

    2000-01-01

    In planta transformation methods are now commonly used to transform Arabidopsis thaliana by Agrobacterium tumefaciens. The origin of transformants obtained by these methods has been studied by inoculating different floral stages and examining gametophytic expression of an introduced beta-glucuronidase marker gene encoding GUS. We observed that transformation can still occur after treating flowers where embryo sacs have reached the stage of the third division. No GUS expression was observed in embryo sacs or pollen of plants infiltrated with an Agrobacterium strain bearing a GUS gene under the control of a gametophyte-specific promoter. To identify the genetic target we used an insertion mutant in which a gene essential for male gametophytic development has been disrupted by a T-DNA bearing a Basta resistance gene (B(R)). In this mutant the B(R) marker is transferred to the progeny only by the female gametes. This mutant was retransformed with a hygromycin resistance marker and doubly resistant plants were selected. The study of 193 progeny of these transformants revealed 25 plants in which the two resistance markers were linked in coupling and only one plant where they were linked in repulsion. These results point to the chromosome set of the female gametophyte as the main target for the T-DNA. PMID:10924482

  8. A Rapid, Highly Efficient and Economical Method of Agrobacterium-Mediated In planta Transient Transformation in Living Onion Epidermis

    PubMed Central

    Xu, Kedong; Huang, Xiaohui; Wu, Manman; Wang, Yan; Chang, Yunxia; Liu, Kun; Zhang, Ju; Zhang, Yi; Zhang, Fuli; Yi, Liming; Li, Tingting; Wang, Ruiyue; Tan, Guangxuan; Li, Chengwei

    2014-01-01

    Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale. PMID:24416168

  9. Barcoding the kingdom Plantae: new PCR primers for ITS regions of plants with improved universality and specificity.

    PubMed

    Cheng, Tao; Xu, Chao; Lei, Li; Li, Changhao; Zhang, Yu; Zhou, Shiliang

    2016-01-01

    The internal transcribed spacer (ITS) of nuclear ribosomal DNA is one of the most commonly used DNA markers in plant phylogenetic and DNA barcoding analyses, and it has been recommended as a core plant DNA barcode. Despite this popularity, the universality and specificity of PCR primers for the ITS region are not satisfactory, resulting in amplification and sequencing difficulties. By thoroughly surveying and analysing the 18S, 5.8S and 26S sequences of Plantae and Fungi from GenBank, we designed new universal and plant-specific PCR primers for amplifying the whole ITS region and a part of it (ITS1 or ITS2) of plants. In silico analyses of the new and the existing ITS primers based on these highly representative data sets indicated that (i) the newly designed universal primers are suitable for over 95% of plants in most groups; and (ii) the plant-specific primers are suitable for over 85% of plants in most groups without amplification of fungi. A total of 335 samples from 219 angiosperm families, 11 gymnosperm families, 24 fern and lycophyte families, 16 moss families and 17 fungus families were used to test the performances of these primers. In vitro PCR produced similar results to those from the in silico analyses. Our new primer pairs gave PCR improvements up to 30% compared with common-used ones. The new universal ITS primers will find wide application in both plant and fungal biology, and the new plant-specific ITS primers will, by eliminating PCR amplification of nonplant templates, significantly improve the quality of ITS sequence information collections in plant molecular systematics and DNA barcoding. PMID:26084789

  10. Bikinin-like inhibitors targeting GSK3/Shaggy-like kinases: characterisation of novel compounds and elucidation of their catabolism in planta

    PubMed Central

    2014-01-01

    Background Plant GSK-3/Shaggy-like kinases are key players in brassinosteroid (BR) signalling which impact on plant development and participate in response to wounding, pathogens and salt stress. Bikinin was previously identified in a chemical genetics screen as an inhibitor targeting these kinases. To dissect the structural elements crucial for inhibition of GSK-3/Shaggy-like kinases by bikinin and to isolate more potent compounds we synthesised a number of related substances and tested their inhibitory activity in vitro and in vivo using Arabidopsis thaliana. Results A pyridine ring with an amido succinic acid residue in position 2 and a halogen in position 5 were crucial for inhibitory activity. The compound with an iodine substituent in position 5, denoted iodobikinin, was most active in inhibiting BIN2 activity in vitro and efficiently induced brassinosteroid-like responses in vivo. Its methyl ester, methyliodobikinin, showed improved cell permeability, making it highly potent in vivo although it had lower activity in vitro. HPLC analysis revealed that the methyl residue was rapidly cleaved off in planta liberating active iodobikinin. In addition, we provide evidence that iodobikinin and bikinin are inactivated in planta by conjugation with glutamic acid or malic acid and that the latter process is catalysed by the malate transferase SNG1. Conclusion Brassinosteroids participate in regulation of many aspects of plant development and in responses to environmental cues. Thus compounds modulating their action are valuable tools to study such processes and may be an interesting opportunity to modify plant growth and performance in horticulture and agronomy. Here we report the development of bikinin derivatives with increased potency that can activate BR signalling and mimic BR action. Methyliodobikinin was 3.4 times more active in vivo than bikinin. The main reason for the superior activity of methyliodobikinin, the most potent compound, is its enhanced plant tissue permeability. Inactivation of bikinin and its derivatives in planta involves SNG1, which constitutes a novel pathway for modification of xenobiotic compounds. PMID:24947596

  11. Mobilization of horizontally acquired island 2 is induced in planta in the phytopathogen Pectobacterium atrosepticum SCRI1043 and involves the putative relaxase ECA0613 and quorum sensing.

    PubMed

    Vanga, Bhanupratap R; Ramakrishnan, Pavithra; Butler, Ruth C; Toth, Ian K; Ronson, Clive W; Jacobs, Jeanne M E; Pitman, Andrew R

    2015-11-01

    Integrative and conjugative elements (ICEs) contribute to the rapid evolution of bacterial pathogens via horizontal gene transfer of virulence determinants. ICEs have common mechanisms for transmission, yet the cues triggering this process under natural environmental or physiological conditions are largely unknown. In this study, mobilization of the putative ICE horizontally acquired island 2 (HAI2), present in the chromosome of the phytopathogen Pectobacterium atrosepticum SCRI1043, was examined during infection of the host plant potato. Under these conditions, mobilization of HAI2 increased markedly compared with in vitro cultures. In planta-induced mobilization of HAI2 was regulated by quorum sensing and involved the putative ICE-encoded relaxase ECA0613. Disruption of ECA0613 also reduced transcription of genes involved in production of coronafacic acid (Cfa), the major virulence factor harboured on HAI2, whereas their expression was unaffected in the quorum-sensing (expI) mutant. Thus, suppression of cfa gene expression was not regulated by the mobilization of the ICE per se, but was due directly to inactivation of the relaxase. The identification of genetic factors associated solely with in planta mobilization of an ICE demonstrates that this process is highly adapted to the natural environment of the bacterial host and can influence the expression of virulence determinants. PMID:26271942

  12. Use of attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy in direct, non-destructive, and rapid assessment of developmental cotton fibers grown in planta and in culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton fibers are routinely harvested from cotton plants (in planta), and their end-use qualities depend on their development stages. Cotton fibers are also cultured at controlled laboratory environments, so that cotton researchers can investigate many aspects of experimental protocols in cotton bre...

  13. Characterization of a highly repeated DNA sequence (SC1) from the arbuscular mycorrhizal fungus Scutellospora castanea and its detection in planta.

    PubMed Central

    Zeze, A; Hosny, M; Gianinazzi-Pearson, V; Dulieu, H

    1996-01-01

    A highly repeated DNA sequence from the genome of an arbuscular mycorrhizal fungus has been isolated and characterized. This 1,202-bp sequence (SC1) represents about 0.24% of the Scutellospora castanea genome, estimated to be 1 pg by flow cytometry. The sequence was shown to be a Scutellospora-specific probe in Southern blots and dot blot hybridizations. After complete sequencing of SC1, PCR primers were generated and used to amplify a 907-bp fragment from spores of S. castanea or from colonized Allium porrum roots. No amplification products were obtained with DNA from either spores or mycorrhizal root of other species of arbuscular mycorrhizal fungi. These primers were sufficiently specific for unequivocal detection of S. castanea in planta. PMID:8779584

  14. Forward Genetic In Planta Screen for Identification of Plant-Protective Traits of Sphingomonas sp. Strain Fr1 against Pseudomonas syringae DC3000

    PubMed Central

    Vogel, Christine; Innerebner, Gerd; Zingg, Judith; Guder, Jan

    2012-01-01

    Sphingomonas sp. strain Fr1 has recently been shown to protect Arabidopsis thaliana against the bacterial leaf pathogen Pseudomonas syringae DC3000. Here, we describe a forward genetic in planta screen to identify genes in Sphingomonas sp. Fr1 necessary for this effect. About 5,000 Sphingomonas sp. Fr1 mini-Tn5 mutants were assayed for a defect in plant protection against a luxCDABE-tagged P. syringae DC3000 derivative in a space-saving 24-well plate system. The bioluminescence of the pathogen was used as the indicator of pathogen proliferation and allowed for the identification of Sphingomonas sp. Fr1 mutants that had lost the ability to restrict pathogen growth before disease symptoms were visible. Potential candidates were validated using the same miniaturized experimental system. Of these mutants, 10 were confirmed as plant protection defective yet colonization competent. The mutants were subsequently evaluated in a previously described standard microbox system, and plants showed enhanced disease phenotypes after pathogen infection relative to those inoculated with the parental strain as a control. However, the disease severities were lower than those observed for control plants that were grown axenically prior to pathogen challenge, which suggests that several traits may contribute to plant protection. Transposon insertion sites of validated mutants with defects in plant protection were determined and mapped to 7 distinct genomic regions. In conclusion, the established screening protocol allowed us to identify mutations that affect plant protection, and it opens the possibility to uncover traits important for in planta microbe-microbe interactions. PMID:22660707

  15. Transient Expression of Secretory IgA In Planta is Optimal Using a Multi-Gene Vector and may be Further Enhanced by Improving Joining Chain Incorporation

    PubMed Central

    Westerhof, Lotte B.; Wilbers, Ruud H. P.; van Raaij, Debbie R.; van Wijk, Christina Z.; Goverse, Aska; Bakker, Jaap; Schots, Arjen

    2016-01-01

    Secretory IgA (sIgA) is a crucial antibody in host defense at mucosal surfaces. It is a promising antibody isotype in a variety of therapeutic settings such as passive vaccination and treatment of inflammatory disorders. However, heterologous production of this heteromultimeric protein complex is still suboptimal. The challenge is the coordinate expression of the four required polypeptides; the alpha heavy chain, the light chain, the joining chain, and part of the polymeric-Ig-receptor called the secretory component, in a 4:4:1:1 ratio. We evaluated the transient expression of three sIgAκ variants, harboring the heavy chain isotype α1, α2m1, or α2m2, of the clinical antibody Ustekinumab in planta. Ustekinumab is directed against the p40 subunit that is shared by the pro-inflammatory cytokines interleukin (IL)-12 and IL-23. A sIgA variant of this antibody may enable localized treatment of inflammatory bowel disease. Of the three different sIgA variants we obtained the highest yield with sIgA1κ reaching up to 373 μg sIgA/mg total soluble protein. The use of a multi-cassette vector containing all four expression cassettes was most efficient. However, not the expression strategy, but the incorporation of the joining chain turned out to be the limiting step for sIgA production. Our data demonstrate that transient expression in planta is suitable for the economic production of heteromultimeric protein complexes such as sIgA. PMID:26793201

  16. The Small Subunit of Snapdragon Geranyl Diphosphate Synthase Modifies the Chain Length Specificity of Tobacco Geranylgeranyl Diphosphate Synthase in Planta[W

    PubMed Central

    Orlova, Irina; Nagegowda, Dinesh A.; Kish, Christine M.; Gutensohn, Michael; Maeda, Hiroshi; Varbanova, Marina; Fridman, Eyal; Yamaguchi, Shinjiro; Hanada, Atsushi; Kamiya, Yuji; Krichevsky, Alexander; Citovsky, Vitaly; Pichersky, Eran; Dudareva, Natalia

    2009-01-01

    Geranyl diphosphate (GPP), the precursor of many monoterpene end products, is synthesized in plastids by a condensation of dimethylallyl diphosphate and isopentenyl diphosphate (IPP) in a reaction catalyzed by homodimeric or heterodimeric GPP synthase (GPPS). In the heterodimeric enzymes, a noncatalytic small subunit (GPPS.SSU) determines the product specificity of the catalytic large subunit, which may be either an active geranylgeranyl diphosphate synthase (GGPPS) or an inactive GGPPS-like protein. Here, we show that expression of snapdragon (Antirrhinum majus) GPPS.SSU in tobacco (Nicotiana tabacum) plants increased the total GPPS activity and monoterpene emission from leaves and flowers, indicating that the introduced catalytically inactive GPPS.SSU found endogenous large subunit partner(s) and formed an active snapdragon/tobacco GPPS in planta. Bimolecular fluorescence complementation and in vitro enzyme analysis of individual and hybrid proteins revealed that two of four GGPPS-like candidates from tobacco EST databases encode bona fide GGPPS that can interact with snapdragon GPPS.SSU and form a functional GPPS enzyme in plastids. The formation of chimeric GPPS in transgenic plants also resulted in leaf chlorosis, increased light sensitivity, and dwarfism due to decreased levels of chlorophylls, carotenoids, and gibberellins. In addition, these transgenic plants had reduced levels of sesquiterpene emission, suggesting that the export of isoprenoid intermediates from the plastids into the cytosol was decreased. These results provide genetic evidence that GPPS.SSU modifies the chain length specificity of phylogenetically distant GGPPS and can modulate IPP flux distribution between GPP and GGPP synthesis in planta. PMID:20028839

  17. In planta production of two peptides of the Classical Swine Fever Virus (CSFV) E2 glycoprotein fused to the coat protein of potato virus X

    PubMed Central

    Marconi, Gianpiero; Albertini, Emidio; Barone, Pierluigi; De Marchis, Francesca; Lico, Chiara; Marusic, Carla; Rutili, Domenico; Veronesi, Fabio; Porceddu, Andrea

    2006-01-01

    Background Classical Swine Fever (CSFV) is one of the most important viral infectious diseases affecting wild boars and domestic pigs. The etiological agent of the disease is the CSF virus, a single stranded RNA virus belonging to the family Flaviviridae. All preventive measures in domestic pigs have been focused in interrupting the chain of infection and in avoiding the spread of CSFV within wild boars as well as interrupting transmission from wild boars to domestic pigs. The use of plant based vaccine against CSFV would be advantageous as plant organs can be distributed without the need of particular treatments such as refrigeration and therefore large areas, populated by wild animals, could be easily covered. Results We report the in planta production of peptides of the classical swine fever (CSF) E2 glycoprotein fused to the coat protein of potato virus X. RT-PCR studies demonstrated that the peptide encoding sequences are correctly retained in the PVX construct after three sequential passage in Nicotiana benthamiana plants. Sequence analysis of RT-PCR products confirmed that the epitope coding sequences are replicated with high fidelity during PVX infection. Partially purified virions were able to induce an immune response in rabbits. Conclusion Previous reports have demonstrated that E2 synthetic peptides can efficiently induce an immunoprotective response in immunogenized animals. In this work we have showed that E2 peptides can be expressed in planta by using a modified PVX vector. These results are particularly promising for designing strategies for disease containment in areas inhabited by wild boars. PMID:16792815

  18. La problematica de la demarcacion entre ciencia y pseudociencia y sus implicaciones en la educacion cientifica

    NASA Astrophysics Data System (ADS)

    Jimenez Tolentino, Dinorah

    2011-12-01

    En la sociedad prevalece una tendencia generalizada hacia la inclusion de creencias y practicas pseudocientificas. Esta investigacion responde a la necesidad de analizar como la proliferacion de las pseudociencias afecta la vision que tienen los estudiantes universitarios sobre las ciencias naturales. A tales efectos, la investigadora describe las concepciones epistemologicas que tienen los estudiantes sobre las ciencias y las pseudociencias e identifica los criterios de demarcacion, entre un area y otra, que se derivan de estas concepciones. De igual modo, esta identifica las creencias y practicas pseudocientificas de mayor arraigo entre los estudiantes, destacando, a su vez, la razon de ser de las mismas. Por ultimo, la investigadora analiza las implicaciones educativas de la problematica de la demarcacion entre ciencia y pseudociencia. La investigacion es de naturaleza mixta, enmarcada en los paradigmas empirico- analitico y cualitativo. El proceso investigativo se llevo a cabo mediante la administracion del cuestionario Criterios para la demarcacion entre ciencia y pseudociencia. La parte cualitativa estuvo enmarcada en el diseno de estudio de caso, recopilando informacion mediante entrevistas semiestructuradas en dos grupos focales. La poblacion de estudio estuvo constituida por estudiantes universitarios del nivel subgraduado de la Universidad Central de Bayamon. Los resultados del estudio reflejaron las concepciones erroneas de los estudiantes sobre la naturaleza de las ciencias y las pseudociencias. Con respecto a la demarcacion entre ciencia y pseudociencia, el criterio imperante entre los universitarios es el de la verificabilidad, considerando la aplicacion del metodo cientifico como el metodo para demostrar la veracidad de las teorias cientificas. Las creencias y practicas pseudocientificas no son muy frecuentes entre los universitarios. Estos atribuyen las mismas a la prevalencia de elementos supersticiosos y al engano a que es sometida la poblacion por quienes promueven estas practicas. A partir de los resultados, la investigadora concluye que la problematica sobre la demarcacion entre ciencia y pseudociencia esta influenciada por unos procesos de ensenanza enfocados en una vision distorsionada de la ciencia, producto de la no integracion de los aspectos filosoficos, historicos y sociales de la misma.

  19. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  20. Activation of an Arabidopsis resistance protein is specified by the in planta association of its leucine-rich repeat domain with the cognate oomycete effector.

    PubMed

    Krasileva, Ksenia V; Dahlbeck, Douglas; Staskawicz, Brian J

    2010-07-01

    Activation of plant immunity relies on recognition of pathogen effectors by several classes of plant resistance proteins. To discover the underlying molecular mechanisms of effector recognition by the Arabidopsis thaliana RECOGNITION OF PERONOSPORA PARASITICA1 (RPP1) resistance protein, we adopted an Agrobacterium tumefaciens-mediated transient protein expression system in tobacco (Nicotiana tabacum), which allowed us to perform coimmunoprecipitation experiments and mutational analyses. Herein, we demonstrate that RPP1 associates with its cognate effector ARABIDOPSIS THALIANA RECOGNIZED1 (ATR1) in a recognition-specific manner and that this association is a prerequisite step in the induction of the hypersensitive cell death response of host tissue. The leucine-rich repeat (LRR) domain of RPP1 mediates the interaction with ATR1, while the Toll/Interleukin1 Receptor (TIR) domain facilitates the induction of the hypersensitive cell death response. Additionally, we demonstrate that mutations in the TIR and nucleotide binding site domains, which exhibit loss of function for the induction of the hypersensitive response, are still able to associate with the effector in planta. Thus, our data suggest molecular epistasis between signaling activity of the TIR domain and the recognition function of the LRR and allow us to propose a model for ATR1 recognition by RPP1. PMID:20601497

  1. Colonization process of olive tissues by Verticillium dahliae and its in planta interaction with the biocontrol root endophyte Pseudomonas fluorescens PICF7

    PubMed Central

    Prieto, Pilar; Navarro‐Raya, Carmen; Valverde‐Corredor, Antonio; Amyotte, Stefan G.; Dobinson, Katherine F.; Mercado‐Blanco, Jesús

    2009-01-01

    Summary The colonization process of Olea europaea by the defoliating pathotype of Verticillium dahliae, and the in planta interaction with the endophytic, biocontrol strain Pseudomonas fluorescens PICF7 were determined. Differential fluorescent protein tagging was used for the simultaneous visualization of P. fluorescens PICF7 and V. dahliae in olive tissues. Olive plants were bacterized with PICF7 and then transferred to V. dahliae‐infested soil. Monitoring olive colonization events by V. dahliae and its interaction with PICF7 was conducted using a non‐gnotobiotic system, confocal laser scanner microscopy and tissue vibratoming sections. A yellow fluorescently tagged V. dahliae derivative (VDAT‐36I) was obtained by Agrobacterium tumefaciens‐mediated transformation. Isolate VDAT‐36I quickly colonized olive root surface, successfully invaded root cortex and vascular tissues via macro‐ and micro‐breakages, and progressed to the aerial parts of the plant through xylem vessel cells. Strain PICF7 used root hairs as preferred penetration site, and once established on/in root tissues, hindered pathogen colonization. For the first time using this approach, the entire colonization process of a woody plant by V. dahliae is reported. Early and localized root surface and root endophytic colonization by P. fluorescens PICF7 is needed to impair full progress of verticillium wilt epidemics in olive. PMID:21255281

  2. Mutations in the capsid protein of Brome mosaic virus affecting encapsidation eliminate vesicle induction in planta: implications for virus cell-to-cell spread.

    PubMed

    Bamunusinghe, Devinka; Chaturvedi, Sonali; Seo, Jang-Kyun; Rao, A L N

    2013-08-01

    Positive-strand RNA viruses are known to rearrange the endomembrane network to make it more conducive for replication, maturation, or egress. Our previous transmission electron microscopic (TEM) analysis showed that ectopic expression of wild-type (wt) capsid protein (CP) of Brome mosaic virus (BMV) has an intrinsic property of modifying the endoplasmic reticulum (ER) to induce vesicles similar to those present in wt BMV infection. In this study, we evaluated the functional significance of CP-mediated vesicle induction to the BMV infection cycle in planta. Consequently, the cytopathologic changes induced by wt CP or its mutants defective in virion assembly due to mutations engineered in either N- or C-proximal domains were comparatively analyzed by TEM in two susceptible (Nicotiana benthamiana and Chenopodium quinoa) and one nonhost (N. clevelandii) plant species. The results showed that in susceptible hosts, CP-mediated ER-derived vesicle induction is contingent on the expression of encapsidation-competent CP. In contrast, unlike in N. benthamiana and C. quinoa, transient expression of wt CP in nonhost N. clevelandii plants eliminated vesicle induction. Additionally, comparative source-to-sink analysis of virus spread in leaves of N. benthamiana and N. clevelandii coexpressing wt BMV and Cucumber mosaic virus (CMV) showed that despite trans-encapsidation, CMV failed to complement the defective cell-to-cell movement of BMV. The significance and relation of CP-mediated vesicle induction to virus cell-to-cell movement are discussed. PMID:23741003

  3. In Planta Biocontrol of Pectobacterium atrosepticum by Rhodococcus erythropolis Involves Silencing of Pathogen Communication by the Rhodococcal Gamma-Lactone Catabolic Pathway

    PubMed Central

    Barbey, Corinne; Crépin, Alexandre; Bergeau, Dorian; Ouchiha, Asma; Mijouin, Lily; Taupin, Laure; Orange, Nicole; Feuilloley, Marc; Dufour, Alain; Burini, Jean-François; Latour, Xavier

    2013-01-01

    The virulence of numerous Gram-negative bacteria is under the control of a quorum sensing process based on synthesis and perception of N-acyl homoserine lactones. Rhodococcus erythropolis, a Gram-positive bacterium, has recently been proposed as a biocontrol agent for plant protection against soft-rot bacteria, including Pectobacterium. Here, we show that the γ-lactone catabolic pathway of R. erythropolis disrupts Pectobacterium communication and prevents plant soft-rot. We report the first characterization and demonstration of N-acyl homoserine lactone quenching in planta. In particular, we describe the transcription of the R. erythropolis lactonase gene, encoding the key enzyme of this pathway, and the subsequent lactone breakdown. The role of this catabolic pathway in biocontrol activity was confirmed by deletion of the lactonase gene from R. erythropolis and also its heterologous expression in Escherichia coli. The γ-lactone catabolic pathway is induced by pathogen communication rather than by pathogen invasion. This is thus a novel and unusual biocontrol pathway, differing from those previously described as protecting plants from phytopathogens. These findings also suggest the existence of an additional pathway contributing to plant protection. PMID:23805254

  4. In Planta Biocontrol of Pectobacterium atrosepticum by Rhodococcus erythropolis Involves Silencing of Pathogen Communication by the Rhodococcal Gamma-Lactone Catabolic Pathway.

    PubMed

    Barbey, Corinne; Crépin, Alexandre; Bergeau, Dorian; Ouchiha, Asma; Mijouin, Lily; Taupin, Laure; Orange, Nicole; Feuilloley, Marc; Dufour, Alain; Burini, Jean-François; Latour, Xavier

    2013-01-01

    The virulence of numerous Gram-negative bacteria is under the control of a quorum sensing process based on synthesis and perception of N-acyl homoserine lactones. Rhodococcus erythropolis, a Gram-positive bacterium, has recently been proposed as a biocontrol agent for plant protection against soft-rot bacteria, including Pectobacterium. Here, we show that the γ-lactone catabolic pathway of R. erythropolis disrupts Pectobacterium communication and prevents plant soft-rot. We report the first characterization and demonstration of N-acyl homoserine lactone quenching in planta. In particular, we describe the transcription of the R. erythropolis lactonase gene, encoding the key enzyme of this pathway, and the subsequent lactone breakdown. The role of this catabolic pathway in biocontrol activity was confirmed by deletion of the lactonase gene from R. erythropolis and also its heterologous expression in Escherichia coli. The γ-lactone catabolic pathway is induced by pathogen communication rather than by pathogen invasion. This is thus a novel and unusual biocontrol pathway, differing from those previously described as protecting plants from phytopathogens. These findings also suggest the existence of an additional pathway contributing to plant protection. PMID:23805254

  5. In Planta Stage-Specific Fungal Gene Profiling Elucidates the Molecular Strategies of Fusarium graminearum Growing inside Wheat Coleoptiles[W][OA

    PubMed Central

    Zhang, Xiao-Wei; Jia, Lei-Jie; Zhang, Yan; Jiang, Gang; Li, Xuan; Zhang, Dong; Tang, Wei-Hua

    2012-01-01

    The ascomycete Fusarium graminearum is a destructive fungal pathogen of wheat (Triticum aestivum). To better understand how this pathogen proliferates within the host plant, we tracked pathogen growth inside wheat coleoptiles and then examined pathogen gene expression inside wheat coleoptiles at 16, 40, and 64 h after inoculation (HAI) using laser capture microdissection and microarray analysis. We identified 344 genes that were preferentially expressed during invasive growth in planta. Gene expression profiles for 134 putative plant cell wall–degrading enzyme genes suggest that there was limited cell wall degradation at 16 HAI and extensive degradation at 64 HAI. Expression profiles for genes encoding reactive oxygen species (ROS)–related enzymes suggest that F. graminearum primarily scavenges extracellular ROS before a later burst of extracellular ROS is produced by F. graminearum enzymes. Expression patterns of genes involved in primary metabolic pathways suggest that F. graminearum relies on the glyoxylate cycle at an early stage of plant infection. A secondary metabolite biosynthesis gene cluster was specifically induced at 64 HAI and was required for virulence. Our results indicate that F. graminearum initiates infection of coleoptiles using covert penetration strategies and switches to overt cellular destruction of tissues at an advanced stage of infection. PMID:23266949

  6. Pea lectin receptor-like kinase promotes high salinity stress tolerance in bacteria and expresses in response to stress in planta.

    PubMed

    Joshi, Amita; Dang, Hung Quang; Vaid, Neha; Tuteja, Narendra

    2010-01-01

    The plant lectin receptor-like kinases (LecRLKs) are involved in various signaling pathways but their role in salinity stress tolerance has not heretofore been well described. Salinity stress negatively affects plant growth/productivity and threatens food security worldwide. Based on functional gene-mining assay, we have isolated 34 salinity tolerant genes out of one million Escherichia coli (SOLR) transformants containing pea cDNAs grown in 0.8 M NaCl. Sequence analysis of one of these revealed homology to LecRLK, which possesses N-myristilation and N-glycosylation sites thus corroborating the protein to be a glycoconjugate. The homology based computational modeling of the kinase domain suggested high degree of conservation with the protein already known to be stress responsive in plants. The NaCl tolerance provided by PsLecRLK to the above bacteria was further confirmed in E. coli (DH5alpha). In planta studies showed that the expression of PsLecRLK cDNA was significantly upregulated in response to NaCl as compared to K(+) and Li(+) ions, suggesting the Na(+) ion specific response. Transcript of the PsLecRLK gene accumulates mainly in roots and shoots. The purified 47 kDa recombinant PsLecRLK-KD (kinase domain) protein has been shown to phosphorylate general substrates like MBP and casein. This study not only suggests the conservation of the cellular response to high salinity stress across prokaryotes and plant kingdom but also provides impetus to develop novel concepts for better understanding of mechanism of stress tolerance in bacteria and plants. It also opens up new avenues for studying practical aspects of plant salinity tolerance for enhanced agricultural productivity. PMID:19898933

  7. In planta assessment of the role of thioredoxin h proteins in the regulation of S-locus receptor kinase signaling in transgenic Arabidopsis.

    PubMed

    Yamamoto, Masaya; Nasrallah, June B

    2013-11-01

    The self-incompatibility (SI) response of the Brassicaceae is mediated by allele-specific interaction between the stigma-localized S-locus receptor kinase (SRK) and its ligand, the pollen coat-localized S-locus cysteine-rich protein (SCR). Based on work in Brassica spp., the thioredoxin h-like proteins THL1 and THL2, which interact with SRK, have been proposed to function as oxidoreductases that negatively regulate SRK catalytic activity. By preventing the spontaneous activation of SRK in the absence of SCR ligand, these thioredoxins are thought to be essential for the success of cross pollinations in self-incompatible plants. However, the in planta role of thioredoxins in the regulation of SI signaling has not been conclusively demonstrated. Here, we addressed this issue using Arabidopsis thaliana plants transformed with the SRKb-SCRb gene pair isolated from self-incompatible Arabidopsis lyrata. These plants express an intense SI response, allowing us to exploit the extensive tools and resources available in A. thaliana for analysis of SI signaling. To test the hypothesis that SRK is redox regulated by thioredoxin h, we expressed a mutant form of SRKb lacking a transmembrane-localized cysteine residue thought to be essential for the SRK-thioredoxin h interaction. We also analyzed transfer DNA insertion mutants in the A. thaliana orthologs of THL1 and THL2. In neither case did we observe an effect on the pollination responses of SRKb-expressing stigmas toward incompatible or compatible pollen. Our results are consistent with the conclusion that, contrary to their proposed role, thioredoxin h proteins are not required to prevent the spontaneous activation of SRK in the A. thaliana stigma. PMID:24077073

  8. Virulence and in planta movement of Xanthomonas hortorum pv. pelargonii are affected by the diffusible signal factor (DSF)-dependent quorum sensing system.

    PubMed

    Barel, Victoria; Chalupowicz, Laura; Barash, Isaac; Sharabani, Galit; Reuven, Michal; Dror, Orit; Burdman, Saul; Manulis-Sasson, Shulamit

    2015-09-01

    Xanthomonas hortorum pv. pelargonii (Xhp), the causal agent of bacterial blight in pelargonium, is the most threatening bacterial disease of this ornamental worldwide. To gain an insight into the regulation of virulence in Xhp, we have disrupted the quorum sensing (QS) genes, which mediate the biosynthesis and sensing of the diffusible signal factor (DSF). Mutations in rpfF (encoding the DSF synthase) and rpfC (encoding the histidine sensor kinase of the two-component system RfpC/RpfG) and overexpression of rpfF showed a significant reduction in incidence and severity of the disease on pelargonium. Confocal laser scanning microscopy images of inoculated plants with a green fluorescent protein (GFP)-labelled wild-type strain showed that the pathogen is homogeneously dispersed in the lumen of xylem vessels, reaching the apex and invading the intercellular spaces of the leaf mesophyll tissue within 21 days. In contrast, the rpfF and rpfC knockout mutants, as well as the rpfF-overexpressing strain, remained confined to the vicinity of the inoculation site. The rpfF and rpfC mutants formed large incoherent aggregates in the xylem vessels that might interfere with upward movement of the bacterium within the plant. Both mutants also formed extended aggregates under in vitro conditions, whereas the wild-type strain formed microcolonies. Expression levels of putative virulence genes in planta were substantially reduced within 48 h after inoculation with the QS mutants when compared with the wild-type. The results presented indicate that an optimal DSF concentration is crucial for successful colonization and virulence of Xhp in pelargonium. PMID:25530086

  9. Boosting In Planta Production of Antigens Derived from the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and Subsequent Evaluation of Their Immunogenicity

    PubMed Central

    Piron, Robin; De Koker, Stefaan; De Paepe, Annelies; Goossens, Julie; Grooten, Johan; Nauwynck, Hans; Depicker, Ann

    2014-01-01

    Porcine reproductive and respiratory syndrome (PRRS) is a disease of swine, caused by an arterivirus, the PRRS virus (PRRSV). This virus infects pigs worldwide and causes huge economic losses. Due to genetic drift, current vaccines are losing their power. Adaptable vaccines could provide a solution to this problem. This study aims at producing in planta a set of antigens derived from the PRRSV glycoproteins (GPs) to be included in a subunit vaccine. We selected the GP3, GP4 and GP5 and optimized these for production in an Arabidopsis seed platform by removing transmembrane domains (Tm) and/or adding stabilizing protein domains, such as the green fluorescent protein (GFP) and immunoglobulin (IgG) ‘Fragment crystallizable’ (Fc) chains. Accumulation of the GPs with and without Tm was low, reaching no more than 0.10% of total soluble protein (TSP) in homozygous seed. However, addition of stabilizing domains boosted accumulation up to a maximum of 2.74% of TSP when GFP was used, and albeit less effectively, also the Fc chains of the porcine IgG3 and murine IgG2a increased antigen accumulation, to 0.96% and 1.81% of TSP respectively, while the murine IgG3 Fc chain did not. Antigens with Tm were less susceptible to these manipulations to increase yield. All antigens were produced in the endoplasmic reticulum and accordingly, they carried high-mannose N-glycans. The immunogenicity of several of those antigens was assessed and we show that vaccination with purified antigens did elicit the production of antibodies with virus neutralizing activity in mice but not in pigs. PMID:24614617

  10. ESTIGMA Y VIH/SIDA ENTRE PADRES/MADRES Y ADOLESCENTES PUERTORRIQUEÑOS/AS

    PubMed Central

    Pérez, Grace Rosado; Reyes, Glendalys Rivera; Villanueva, Victoria Larrieux; Torres, Gilliam J. Torres; Díaz, Elba Betancourt; Varas-Díaz, Nelson; Villaruel, Antonia

    2016-01-01

    La comunicación entre padres/madres y adolescentes sobre el tema de la sexualidad es importante para el desarrollo de la salud de personas jóvenes. Dicha comunicación puede verse negativamente impactada por actitudes estigmatizantes hacia el tema del VIH/SIDA. El objetivo de este estudio fue identificar actitudes estigmatizantes hacia el VIH/SIDA entre padres/madres y adolescentes puertorriqueños/as. Este esfuerzo es parte del Proyecto Cuídalos, dirigido a probar una intervención en formato electrónico que busca aumentar la comunicación sobre sexualidad y salud entre padres/madres y adolescentes mediante un diseño experimental con 458 diadas de padres/madres y adolescentes de 13 a 17 años. Para propósitos de este artículo reportamos estadísticas descriptivas sobre estigma hacia el VIH/SIDA con la información recopilada en la medición basal. Tanto adultos/as como adolescentes mostraron actitudes estigmatizantes hacia el VIH/SIDA. A la luz de los resultados es necesario continuar desarrollando intervenciones para la reducción de estigma en esta población. Los/as padres/madres pueden ser un recurso invaluable para reducir el estigma en los/as jóvenes, y prevenir conductas sexuales de riesgo e infecciones. PMID:27099649

  11. Estudo comparativo entre estrelas centrais de nebulosas planetárias deficientes em hidrogênio

    NASA Astrophysics Data System (ADS)

    Marcolino, W. L. F.; de Araújo, F. X.

    2003-08-01

    Apresentamos neste trabalho o resultado de um estudo das principais características espectrais das estrelas centrais de nebulosas planetárias (ECNP) deficientes em hidrogênio. A origem e a evolução dessas estrelas ainda constitui um problema em aberto na evolução estelar. Geralmente esses objetos são divididos em [WCE], [WCL] e [WELS]. Os tipos [WCE] e [WCL] apresentam um espectro típico de uma estrela Wolf-Rayet carbonada de população I e as [WELS] apresentam linhas fracas de carbono e oxigênio em emissão. Existem evidências que apontam a seguinte sequência evolutiva : [WCL] = > [WCE] = > [WELS] = > PG 1159 (pré anã-branca). No entanto, tal cenário apresenta falhas como por exemplo a falta de ECNP entre os tipos [WCL] e [WCE]. Baseados em uma amostra de 24 objetos obtida no telescópio de 1.52m em La Silla, Chile (acordo ESO/ON), ao longo do ano 2000, apresentamos os resultados da comparação das larguras equivalentes de diversas linhas relevantes entre os tipos [WCL], [WCE] e [WELS]. Verificamos que nossos dados estão de acordo com a sequência evolutiva. Baseado nas linhas de C IV, conseguimos dividir pela primeira vez as [WELS] em dois grupos principais. Além disso, os dados reforçam a afirmação de que as [WCE] são as estrelas que possuem a maior temperatura entre as ECNP deficientes em hidrogênio. Discutimos ainda, a escassez de dados disponíveis na literatura e a necessidade da obtenção de parametros físicos para estes objetos.

  12. Differential subcellular targeting of recombinant human α₁-proteinase inhibitor influences yield, biological activity and in planta stability of the protein in transgenic tomato plants.

    PubMed

    Jha, Shweta; Agarwal, Saurabh; Sanyal, Indraneel; Jain, G K; Amla, D V

    2012-11-01

    The response of protein accumulation site on yield, biological activity and in planta stability of therapeutic recombinant human proteinase inhibitor (α₁-PI) was analyzed via targeting to different subcellular locations, like endoplasmic reticulum (ER), apoplast, vacuole and cytosol in leaves of transgenic tomato plants. In situ localization of the recombinant α₁-PI protein in transgenic plant cells was monitored by immunohistochemical staining. Maximum accumulation of recombinant α₁-PI in T₀ and T₁ transgenic tomato plants was achieved from 1.5 to 3.2% of total soluble protein (TSP) by retention in ER lumen, followed by vacuole and apoplast, whereas cytosolic targeting resulted into degradation of the protein. The plant-derived recombinant α₁-PI showed biological activity for elastase inhibition, as monitored by residual porcine pancreatic elastase (PPE) activity assay and band-shift assay. Recombinant α₁-PI was purified from transgenic tomato plants with high yield, homogeneity and biological activity. Purified protein appeared as a single band of ∼48-50 kDa on SDS-PAGE with pI value ranging between 5.1 and 5.3. Results of mass spectrometry and optical spectroscopy of purified recombinant α₁-PI revealed the structural integrity of the recombinant protein comparable to native serum α₁-PI. Enzymatic deglycosylation and lectin-binding assays with the purified recombinant α₁-PI showed compartment-specific N-glycosylation of the protein targeted to ER, apoplast and vacuole. Conformational studies based on urea-induced denaturation and circular dichroism (CD) spectroscopy revealed relatively lower stability of the recombinant α₁-PI protein, compared to its serum counterpart. Pharmacokinetic evaluation of plant derived recombinant and human plasma-purified α₁-PI in rat, by intravenous route, revealed significantly faster plasma clearance and lower area under curve (AUC) of recombinant protein. Our data suggested significance of protein sorting sequences and feasibility to use transgenic plants for the production of stable, glycosylated and biologically active recombinant α₁-PI for further therapeutic applications. PMID:23017899

  13. Genomic homologous recombination in planta.

    PubMed Central

    Gal, S; Pisan, B; Hohn, T; Grimsley, N; Hohn, B

    1991-01-01

    A system for monitoring intrachromosomal homologous recombination in whole plants is described. A multimer of cauliflower mosaic virus (CaMV) sequences, arranged such that CaMV could only be produced by recombination, was integrated into Brassica napus nuclear DNA. This set-up allowed scoring of recombination events by the appearance of viral symptoms. The repeated homologous regions were derived from two different strains of CaMV so that different recombinant viruses (i.e. different recombination events) could be distinguished. In most of the transgenic plants, a single major virus species was detected. About half of the transgenic plants contained viruses of the same type, suggesting a hotspot for recombination. The remainder of the plants contained viruses with cross-over sites distributed throughout the rest of the homologous sequence. Sequence analysis of two recombinant molecules suggest that mismatch repair is linked to the recombination process. Images PMID:2026150

  14. Transfert radiatif entre une petite particule et un diélectrique: application au chauffage local

    NASA Astrophysics Data System (ADS)

    Mulet, J.-P.; Joulain, K.; Carminati, R.; Greffet, J. J.

    2002-06-01

    nous montrons dans cette étude que le transfert radiatif entre une particule de taille nanométrique et un diélectrique petit être très important lorsque les distances mises en jeu sont petites devant la longueur d'onde caractéristique du rayonnement thermique. Ce transfert peut devenir dominant lorsque les matériaux utilisés sont polaires. Nous discuterons de la possibilité d'appliquer ces résultats au chauffage local dans les nano-structures.

  15. An Environmental Management Model of Thermal Waters in Entre Ríos Province, Argentina

    NASA Astrophysics Data System (ADS)

    Pablo, Mársico Daniel; Luís, Díaz Eduardo; Ivana, Zecca; Oscar, Dallacosta; Antonio, Paz-González

    2015-04-01

    Deep exploratory drillings, i.e. those with more than 500 meters depth, have been performed in the Entre Ríos province, Argentina, in order to ascertain the presence of thermal water. Drilling began in 1994, and until now there have been 18 polls with very variable results in terms of mineralization, resource flow, and temperature. The aim of this study was to present a management model, which should allow operators of thermal complexes to further develop procedures for safeguarding the biodiversity of the ecosystems involved, both during exploration and exploitation activities. The environmental management Plan proposed is constituted by a set of technical procedures that are formulated and should be performed during the stages of exploration and exploitation of the resource, and consists of: environmental monitoring, environmental audit, public information and contingency programs. This Plan describes the measures and proposals aimed at protecting environmental quality in the area of influence of a thermal complex project, ensuring that its execution remains environmentally responsibly, and allowing implementation of specific actions to prevent or correct environmental impacts, as predicted in the evaluation of the Environmental Program. The audit of environmental impact includes and takes into account natural factors, such as water, soil, atmosphere, flora and fauna, and also cultural factors. The technical audit Plan was prepared in order to get a systematic structure and organization of the verification process, and also with regard to document the degree of implementation of the proposed mitigation measures. Finally, an environmental contingency program was implemented, and its objective was to consider the safeguarding of life and its natural environment. Thus, a guide has been developed with the main actions to be taken on a contingency, since forecast increases the efficiency of the response. The methodology developed here was adopted as the procedure required by the authority for the application and regulation of the hydro-geo-thermal resources of the province of Entre Ríos, and it is also useful for the control and protection of the resource.

  16. No Financial Disincentive for Choosing More Healthful Entrées on Children’s Menus in Full-Service Restaurants

    PubMed Central

    West, Delia

    2013-01-01

    Children are eating restaurant foods more than ever before, and price is among the top considerations for food choices. We categorized and enumerated entrées on children’s menus from 75 full-service restaurant chains to compare prices of more healthful and less healthful entrées to test the assumption that more healthful food is more expensive. The mean (standard deviation) price of more healthful entrées ($5.38 [$2.01]) was not significantly different from the price of less healthful entrées ($5.27 [$2.04]). In contrast to research demonstrating that more healthful foods tend to be more expensive in grocery stores, more healthful entrées on children’s menus in restaurants were not more expensive than less healthful entrées. PMID:23742942

  17. A full-length infectious clone of beet soil-borne virus indicates the dispensability of the RNA-2 for virus survival in planta and symptom expression on Chenopodium quinoa leaves.

    PubMed

    Crutzen, François; Mehrvar, Mohsen; Gilmer, David; Bragard, Claude

    2009-12-01

    For a better understanding of the functionality and pathogenicity of beet soil-borne virus (BSBV), full-length cDNA clones have been constructed for the three genomic RNAs. With the aim of assessing their effectiveness and relative contribution to the virus housekeeping functions, transcripts were inoculated on Chenopodium quinoa and Beta macrocarpa leaves using five genome combinations. Both RNAs-1 (putative replicase) and -3 (putative movement proteins) proved to be essential for virus replication in planta and symptom production on C. quinoa, whereas RNA-2 (putative coat protein, CP, and a read-through domain, RT) was not. No symptoms were recorded on B. macrocarpa, but viral RNAs were detected. In both host plants, the 19 kDa CP was detected by Western blotting as well as a 115 kDa protein corresponding to the CP-RT. PMID:19726609

  18. Religiosidade, juventude e sexualidade: entre a autonomia e a rigidez1

    PubMed Central

    Silva, Cristiane Gonçalves da; Santos, Alessandro Oliveira; Licciardi, Daniele Carli; Paiva, Vera; Parker, Richard

    2009-01-01

    Esse artigo descreve como jovens religiosos e autoridades religiosas de sua comunidade compreendem a sexualidade, considerando suas experiências pessoais e como membros de comunidades religiosas. A análise pretende contribuir para que políticas públicas dedicadas à promoção da saúde sexual da juventude considerem a religiosidade, no contexto de um estado laico e da promoção do direito à prevenção. Foram realizadas 26 entrevistas abertas e semidirigidas em diferentes comunidades da região metropolitana da cidade de São Paulo (comunidades católicas, da umbanda, do candomblé e de diferentes denominações evangélicas) sobre iniciação sexual, casamento, gravidez, contracepção e prevenção das DST/Aids, homossexualidade, aborto e direitos humanos. Observou-se como jovens e autoridades religiosas convivem com a tensão entre tradição e modernidade e os distintos discursos sobre a sexualidade. Como sujeitos religiosos (do discurso religioso) e sujeitos sexuais (de discursos sobre sexualidade), devem ser incorporados pelos programas como sujeitos de direito nos termos de sua religiosidade. PMID:21886456

  19. El espanol...! A distancia!: Developing a Technology-based Distance Education Course for Intermediate Spanish.

    ERIC Educational Resources Information Center

    Rogers, Donna M.; Wolff, Andrew B.

    2000-01-01

    Describes the development and implementation of a pilot technology-driven intermediate Spanish course at Pennsylvania State University. Looks at the use of four technologies--synchronous chat, Web and multimedia training, computer-based grammar practice, and asynchronous (E-mail) conferencing--in this foreign language course. Summarizes some…

  20. El espectro de KX TrA entre 1990 y 1996

    NASA Astrophysics Data System (ADS)

    Brandi, E.; García, L.; Ferrer, O.; Barbá, R.

    La estrella simbiótica KX TrA = He2-177 fue observada espectroscópicamente con el telescopio de 2.15 m del CASLEO entre los años 1990 y 1996, utilizándose resoluciones intermedia y alta. El rango espectral estudiado se extiende desde 4400 Åa 7200 Å. La historia fotométrica de KX TrA presenta explosiones del mismo tipo que las mostradas por la nova lenta RR Tel y su espectro de alta excitación, muy rico en líneas de emisión, es también similar al de RR Tel. Por lo tanto, es importante analizar la evolución espectral de KX TrA en el tiempo, prestando especial atención a los posibles cambios en los niveles de excitación. Las emisiones presentes corresponden a transiciones permitidas y prohibidas con un amplio rango de ionización, incluyéndose las anchas e intensas líneas originadas por scattering Raman de O VI en λλ 6825 y 7082 Å. En el período cubierto por nuestras observaciones se estudia la variación de la intensidad relativa de las emisiones, el comportamiento de las velocidades radiales y los cambios de perfiles de las líneas, especialmente en Hα y Hβ. El contínuo de la región roja observada indica un tipo espectral no más tardío que M3 para la componente gigante fría del sistema.

  1. Analyse des interactions energetiques entre un arena et son systeme de refrigeration

    NASA Astrophysics Data System (ADS)

    Seghouani, Lotfi

    La presente these s'inscrit dans le cadre d'un projet strategique sur les arenas finance par le CRSNG (Conseil de Recherche en Sciences Naturelles et en Genie du Canada) qui a pour but principal le developpement d'un outil numerique capable d'estimer et d'optimiser la consommation d'energie dans les arenas et curlings. Notre travail s'inscrit comme une suite a un travail deja realise par DAOUD et coll. (2006, 2007) qui a developpe un modele 3D (AIM) en regime transitoire de l'arena Camilien Houde a Montreal et qui calcule les flux de chaleur a travers l'enveloppe du batiment ainsi que les distributions de temperatures et d'humidite durant une annee meteorologique typique. En particulier, il calcule les flux de chaleur a travers la couche de glace dus a la convection, la radiation et la condensation. Dans un premier temps nous avons developpe un modele de la structure sous la glace (BIM) qui tient compte de sa geometrie 3D, des differentes couches, de l'effet transitoire, des gains de chaleur du sol en dessous et autour de l'arena etudie ainsi que de la temperature d'entree de la saumure dans la dalle de beton. Par la suite le BIM a ete couple le AIM. Dans la deuxieme etape, nous avons developpe un modele du systeme de refrigeration (REFSYS) en regime quasi-permanent pour l'arena etudie sur la base d'une combinaison de relations thermodynamiques, de correlations de transfert de chaleur et de relations elaborees a partir de donnees disponibles dans le catalogue du manufacturier. Enfin le couplage final entre l'AIM +BIM et le REFSYS a ete effectue sous l'interface du logiciel TRNSYS. Plusieurs etudes parametriques on ete entreprises pour evaluer les effets du climat, de la temperature de la saumure, de l'epaisseur de la glace, etc. sur la consommation energetique de l'arena. Aussi, quelques strategies pour diminuer cette consommation ont ete etudiees. Le considerable potentiel de recuperation de chaleur au niveau des condenseurs qui peut reduire l'energie requise par le systeme de ventilation de l'arena a ete mis en evidence. Mots cles. Arena, Systeme de refrigeration, Consommation d'energie, Efficacite energetique, Conduction au sol, Performance annuelle.

  2. An updated model for nitrate uptake modelling in plants. I. Functional component: cross-combination of flowforce interpretation of nitrate uptake isotherms, and environmental and in planta regulation of nitrate influx

    PubMed Central

    Le Deunff, Erwan; Malagoli, Philippe

    2014-01-01

    Background and Aims In spite of major breakthroughs in the last three decades in the identification of root nitrate uptake transporters in plants and the associated regulation of nitrate transport activities, a simplified and operational modelling approach for nitrate uptake is still lacking. This is due mainly to the difficulty in linking the various regulations of nitrate transport that act at different levels of time and on different spatial scales. Methods A cross-combination of a FlowForce approach applied to nitrate influx isotherms and experimentally determined environmental and in planta regulation is used to model nitrate in oilseed rape, Brassica napus. In contrast to EnzymeSubstrate interpretations, a FlowForce modelling approach considers the root as a single catalytic structure and does not infer hypothetical cellular processes among nitrate transporter activities across cellular layers in the mature roots. In addition, this approach accounts for the driving force on ion transport based on the gradient of electrochemical potential, which is more appropriate from a thermodynamic viewpoint. Key Results and Conclusions Use of a FlowForce formalism on nitrate influx isotherms leads to the development of a new conceptual mechanistic basis to model more accurately N uptake by a winter oilseed rape crop under field conditions during the whole growth cycle. This forms the functional component of a proposed new structurefunction mechanistic model of N uptake. PMID:24638820

  3. Seroprevalence of Salmonella and Mycoplasma infection in backyard chickens in the state of Entre Rios in Argentina.

    PubMed

    Xavier, J; Pascal, D; Crespo, E; Schell, H L; Trinidad, J A; Bueno, D J

    2011-04-01

    The present work was conducted to study the seroprevalence of Salmonella, Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS) infection in backyard chickens located in Entre Ríos, Argentina, over 3 periods of time. A total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of Entre Ríos from January to May 2003 (first period), December 2004 to April 2005 (second period), and October 2006 to May 2007 (third period). The prevalence of family farms testing seropositive for Salmonella averaged 23.9, 15.9, and 28.6% during the first, second, and third period, respectively. The highest prevalence of Salmonella-seropositive farms recorded (66.7%) was on farms from Concordia county, and the lowest prevalence (0%) was on farms from La Paz county. In contrast, the prevalence of family farms seropositive for MG averaged 32.8, 55.1, and 76.2% during the first, second, and third periods, respectively. The highest prevalence of MG-seropositive farms (100%) was found in the counties of Victoria and Tala, and the lowest prevalence (8.7%) was found on farms on Colón county. The prevalence of family farms seropositive for MS averaged 68.6 and 100% during the first and second periods, respectively. The highest prevalence of MS-seropositive farms (100%) was on farms in 85% of the counties tested, and the lowest prevalence (21.7%) was on farms from Colón county. Salmonella, MG, and MS infection are present at high levels in backyard chicken farms, and this presents a high risk to commercial poultry production in Entre Ríos, the state with the highest chicken population and density in Argentina. PMID:21406358

  4. In planta processing and glycosylation of a nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-like effector and its interaction with a host CLAVATA2-like receptor to promote parasitism.

    PubMed

    Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S; Mitchum, Melissa G; Wang, Xiaohong

    2015-01-01

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. PMID:25416475

  5. In Planta Processing and Glycosylation of a Nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-Like Effector and Its Interaction with a Host CLAVATA2-Like Receptor to Promote Parasitism1[OPEN

    PubMed Central

    Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S.; Mitchum, Melissa G.

    2015-01-01

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. PMID:25416475

  6. Etude de la transition tribologique entre le fretting et le meso-fretting pour des materiaux de contact electrique

    NASA Astrophysics Data System (ADS)

    Gagnon, Daniel

    Dans les installations electriques, les contacts sont toujours soumis a des contraintes alternees ou a des micro-deplacements. Il en resulte une corrosion par fretting, phenomene defini comme un type de deterioration de la surface qui se produit lorsque deux materiaux en contact sont soumis a des mouvements microscopiques d'oscillations de tres faible amplitude (0 a 100 mum). Ceci a pour effet de provoquer une degradation de la resistance de contact et une interruption du passage du courant. Ce phenomene a des repercussions considerables sur le plan pratique puisque les micro-deplacements de pieces en contact peuvent etre causes par la dilatation thermique differentielle des metaux, par des vibrations mecaniques, par la relaxation des contraintes ou par l'echauffement des contacts lorsqu'on interrompt et retablit le courant. Nous avons donc dans le cadre de cette these etudie plusieurs aspects du fretting (0--100 mum) et du meso-fretting (100 a 1000 mum) pour differents materiaux de contact electrique. Des travaux experimentaux ont ete realises a partir de deux montages reproduisant divers aspects de la degradation par le fretting. Un premier montage de fretting de type bille-plaque a ete entierement developpe a l'ETS et un second montage, de type fil-plaque a ete utilise en collaboration avec Hydro Quebec IREQ a Varennes. Plusieurs techniques de mesures et d'analyse relevant tant du domaine de la mecanique du contact que de la metallurgie ont ete utilisees pour traiter les resultats. L'influence du courant sur le taux d'usure et la force de friction a ete examinee pour divers materiaux de contacts. Des essais de fatigue thermique et electrique ont ete realises sur divers materiaux et lubrifiants de contact. Il a ete demontre que pour le domaine entre 100 mum et 1000 mum, le taux d'usure n'est pas le meme de 0 a 100 mum et au dela de 1000 mum. La plupart des materiaux evalues montrent un stade de comportement intermediaire dont le debut se situe entre 100 mum et 300 mum. Lorsque l'on substitut le courant CC a un courant CA de 60 Hz ou 400 HZ, la morphologie des debris aux abords de la zone de contact est differente. De plus, lors de la comparaison du vieillissement thermique par conduction versus par chauffage electrique de certains alliages sans plomb, il a ete montre qu'il pourrait y avoir une difference entre les deux en ce qui concerne le taux de croissance des phases intermetalliques.

  7. Clostridium perfringens growth from spore inocula in sous-vide processed pork-based Mexican entrée.

    PubMed

    Miguel-Garcia, Denise Y; Juneja, Vijay K; Valenzuela-Melendrez, Martin; Díaz-Cinco, Martha E; Thippareddi, H; Aida Peña-Ramos, E

    2009-01-01

    The combined effect of Citricidal wih irradiation on Clostridium perfringens growth from spores in a sous-vide processed marinated pork meat Mexican entrée was investigated. Citricidal was added at 200 or 800 ppm after mixing pork meat with tomatillo sauce and inoculated with 3 log(10) CFU/g of C. perfringens spores. Samples were irradiated at either 0 or 2 kGy, heated to an internal temperature of 71 degrees C, and stored at 4 degrees C for 28 d, 15 degrees C for 45 d, and 25 degrees C for 26 h. To simulate the conditions that may occur during transportation, distribution, storage, or handling in supermarkets or by consumers, the effect of static temperature abuse on C. perfringens growth was assessed by transferring samples stored at 4 to 25 degrees C for 13 and 15 h. Total C. perfringens populations were determined by plating diluted samples on tryptose-sulfite-cycloserine agar. Growth was not observed up to 45 d of storage at 15 degrees C in samples supplemented with 800 ppm of Citricidal. At 25 degrees C, no significant differences (P > 0.05) on the lag phase duration due to antimicrobial treatments was observed. The temperature abuse of refrigerated products for up to 15 h did not lead to C. perfringens growth to high infective dose levels of 1 million cells required to cause food poisoning. The results suggest that 800 ppm Citricidal can have significant bacteriostatic activity against C. perfringens and may provide a degree of protection against this pathogen in sous-vide processed marinated pork meat Mexican entrée, under mild temperature abuse (

  8. Characterization of copy numbers of 16S rDNA and 16S rRNA of Candidatus Liberibacter asiaticus and the implication in detection in planta using quantitative PCR

    PubMed Central

    Kim, Jeong-soon; Wang, Nian

    2009-01-01

    Background Citrus Huanglongbing (HLB) is one of the most devastating diseases on citrus and is associated with Candidatus Liberibacter spp.. The pathogens are phloem limited and have not been cultured in vitro. The current management strategy of HLB is to remove infected citrus trees and reduce psyllid populations with insecticides to prevent the spreading. This strategy requires sensitive and reliable diagnostic methods for early detection. Results We investigated the copy numbers of the 16S rDNA and 16S rRNA of the HLB pathogen and the implication of improving the diagnosis of HLB for early detection using Quantitative PCR. We compared the detection of HLB with different Quantitative PCR based methods with primers/probe targeting either 16S rDNA, beta-operon DNA, 16S rRNA, or beta-operon RNA. The 16S rDNA copy number of Ca. Liberibacter asiaticus was estimated to be three times of that of the beta-operon region, thus allowing detection of lower titer of Ca. L. asiaticus. Quantitative reverse transcriptional PCR (QRT-PCR) indicated that the 16S rRNA averaged 7.83 times more than that of 16S rDNA for the same samples. Dilution analysis also indicates that QRT-PCR targeting 16S rRNA is 10 time more sensitive than QPCR targeting 16S rDNA. Thus QRT-PCR was able to increase the sensitivity of detection by targeting 16S rRNA. Conclusion Our result indicates that Candidatus Liberibacter asiaticus contains three copies of 16S rDNA. The copy number of 16S rRNA of Ca. L. asiaticus in planta averaged about 7.8 times of 16S rDNA for the same set of samples tested in this study. Detection sensitivity of HLB could be improved through the following approaches: using 16S rDNA based primers/probe in the QPCR assays; and using QRT-PCR assays targeting 16S rRNA. PMID:19284534

  9. Soil Quality Indicators to Define Land Use in the Area of Native Forest of Entre Ríos, Argentina

    NASA Astrophysics Data System (ADS)

    Wilson, M. G.; Tasi, H. A.; Paz González, A.; Díaz, E. L.; Sasal, M. C.

    2012-04-01

    The main economic activity in the area of native forest of the province of Entre Ríos (Argentina) has long been the agricultural and/or livestock production, especially cattle breeding. In recent years, the proportion of agricultural crops in the rotations, especially that of soybean, has increased, thus leading to an increase in the need for land clearing to incorporate new lands for agricultural use. Most of these lands are considered marginal for agricultural use. In addition rice farming with irrigation is a critical part of the Entre Ríos economy. Defining and assessing soil quality indicators (SQI) that show the evolution of the soil with different uses and management systems is a way to contribute to the knowledge of soil quality. The aims of this study were to characterize the current land use and land tenure in the area of native forest of Entre Ríos, as well as to identify and select variables sensitive to agricultural and/or livestock use of the most representative soils of this area (indicators of the dynamic quality of the soil) and define the most appropriate land use according to land suitability and behavior of these indicators. We identified the most representative soil subgroups (corresponding to the orders Vertisols, Mollisols and Alfisols) and defined the production systems livestock-agricultural, agricultural-livestock, agricultural without irrigation, and rice crop irrigated with water from groundwater and surface reservoirs. We also determined the physical, physico-chemical, chemical and microbiological variables of the soil, and characterized the quality of the water for irrigation. We selected the SQI using Principal Components Analysis, to form a minimum data set (MDS). The change in the use of the land responded to a favorable economic situation for agriculture that started in the 1990's. The leasing and sharecropping schemes and the incidental contracts have become increasingly important, predominating over the undivided property. We obtained the MDS for twelve combinations of soil subgroups and production systems. The MDS for each of them presented between six and nine SQI. The indicators showed greater variation in the MDS by production system than by unit of land. Total organic carbon content (TOC) and the structural stability index (Is) were included in all the MDS. The rice systems showed high dependence on the quality of the irrigation water. We also found high fragility of some soil subgroups. The results suggest that rotations including pastures in a high proportion should be considered, especially in Alfisols and Vertisols. The native forest is considered as the basis of sustainable production systems for the study area. Thus, the land that has already been cleared or is about to be cleared should consider an agricultural and/or livestock use according to its productive capacity and its limitations.

  10. Competition entre les phases ferromagnetique metallique et ordre de charges a l'interface de manganites a magnetoresistance colossale

    NASA Astrophysics Data System (ADS)

    Laverdiere, Jonathan

    Dans la these qui suit, l'interaction entre deux manganites a magnetoresistance colossale domines par des phases antagonistes est etudiee a l'interface de bicouches. Un manganite isolant anti-ferromagnetique presentant une phase d'ordre de charges a basse temperature et un manganite metallique domine par les interactions ferromagnetiques. L'objectif est de verifier si l'interaction entre ces deux manganites est susceptible de soit 1) affaiblir la stabilite de l'ordre de charges ou soit 2) de rendre la phase metallique plus resistive afin d'ameliorer les proprietes de magnetoresistance colossale. Deux series de bicouches ont ete preparees par depot par ablation laser pulse et analysees avec une combinaison de plusieurs methodes experimentales telles que la mesure de resistance electrique, la spectroscopie Raman, la mesure d'aimantation et la diffraction des rayons X. Dans la premiere serie de bicouches, la configuration utilisee consiste en une couche tampon ferromagnetique sur laquelle une couche de manganite a ordre de charges est deposee. Il s'est avere que la phase d'ordre de charges n'est pas destabilisee par la phase ferromagnetique metallique dans une couche d'ordre de charges aussi mince que 10 nm. Les mesures de resistance montrent que la phase isolante demeure difficile a rendre metallique sous l'application d'un champ magnetique. La spectroscopie Raman montre egar lement une phase d'ordre de charges tres stable et suggere que les contraintes mecaniques appliquees par la couche tampon sont responsables de cette stabilite, malgre la presence de la phase ferromagnetique a proximite. Dans la deuxieme serie de bicouches, la configuration utilisee consiste en une couche tampon presentant de l'ordre de charges sur laquelle une couche ferromagnetique metallique est deposee. La diminution de l'epaisseur de la couche ferromagnetique metallique se repercute sur une diminution de la temperature de Curie et de la transition metal-isolant. Entre 4 et 5 nm, la transition metal-isolant est supprimee et la bicouche demeure isolante a toutes les temperatures. Dans la bicouche ayant une couche ferromagnetique de 4 nm, la transition metal-isolant est retrouvee sous l'application d'un champ magnetique de 1.5 T et une magnetoresistance de 50% est obtenue a 75K sous l'application d'un champ magnetique de 0.5 T. Un changement dans le champ magnetique necessaire a l'aimantation de la couche d'ordre de charges est egalement mesure, suggerant que la couche ferromagnetique induit des domaines ferromagnetiques dans la couche tampon. Ces resultats sont expliques par l'interaction mecanique dominant l'interface et favorisant la localisation des charges. L'anisotropie de la contrainte mecanique semble jouer un role supplementaire comparativement aux contraintes procurees par un substrat cubique. La rotation des octaedres ou la distorsion de Jahn-Teller, deux distorsions locales, pourraient contribuer a la tendance a localiser les charges. De plus, la phase isolante mesuree dans le Nd2/3Sr 1/3O3, normalement metallique, demeure plus sensible au champ magnetique que la phase isolante induite dans ce meme materiau par un substrat cubique isolant. La domination des contraintes mecaniques sur les influences ferromagnetiques suggere que cette influence soit le vecteur principal pour le controle de la separation de phases electroniques des manganites.

  11. State of Conservation of the Native Forests in Entre Ríos (Argentina) and Changes in Land Use

    NASA Astrophysics Data System (ADS)

    Sabattini, R. A.; Sione, S. M.; Ledesma, S. G.; Sabattini, J. A.; Wilson, M. G.

    2012-04-01

    The native forest area of Entre Ríos province (Argentina) is associated with a constant change in land use, with an increase in recent years in agricultural use, especially for soybean crop. In addition, since its inadequate management has triggered degradation processes of the natural forest structure, the implementation of strategies for the restoration and conservation of native forests has become a priority. The aim of this study was to diagnose the conservation state of the native forest in the basin of the Estacas Stream (Entre Ríos, Argentina) after the change in land use, to help design guidelines for the restoration and sustainable management of these ecosystems. The field study was conducted in October 2010, in a representative area of the native forest of 73,000 ha. Using Landsat 5-TM images (INPE), environments were separated by manual vectorization, identifying and classifying native forests and other lands (agricultural, urban). Using a field exploratory survey (58 geo-referenced sampling points), we developed patterns corresponding to the different types of forests, contrasting this information with the digital data of the images. The native forests were classified according to type (high/low forest, open/closed forest, savanna), successional stage (climax, successional or regeneration forest) and degree of disturbance (weed growth, erosion, fire), and their frequency determined. Each classification was assessed by a contingency matrix, and global reliability index and the Kappa index. The information obtained generated a classification map of native forests in the basin scale. We found that the native forest covered an area of 42,726.91 ha, accounting for 58.52% of the total basin area, and that the rest corresponded to other land uses. The most frequent native forests (59.09%) were climax forest, but accounted for only 8.2% of the basin area. Within this group, the most important were the low and open forest, with Prosopis affinis and Prosopis nigra as the dominant tree species. Although the successional forests were not the most frequent, they occupied the greater area of the basin (30.8%), being low and open forest the dominant type. The regeneration forest dominated by Acacia caven, represents 18.71% of the basin area. Weed shrub species growth was the most frequent disturbance. We determined a severe weed shrub growth in 41% of the sampling points, with Baccharis punctulata and Eupatorium buniifolium as the dominant species. According to state of conservation of native forest, 7,797.03 ha have a high conservation value, while 21,272.17 ha and 13,657.71 ha have a medium and low conservation value, respectively.

  12. A Process Evaluation of an Efficacious Family-Based Intervention to Promote Healthy Eating: The "Entre Familia: Reflejos de Salud" Study

    ERIC Educational Resources Information Center

    Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe

    2015-01-01

    "Entre Familia: Reflejos de Salud" was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker ("promotora") model with an entertainment-education…

  13. A Process Evaluation of an Efficacious Family-Based Intervention to Promote Healthy Eating: The "Entre Familia: Reflejos de Salud" Study

    ERIC Educational Resources Information Center

    Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe

    2015-01-01

    "Entre Familia: Reflejos de Salud" was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker ("promotora") model with an entertainment-education

  14. Natural co-occurrence of fungi and mycotoxins in poultry feeds from Entre Ríos, Argentina.

    PubMed

    Monge, M P; Dalcero, A M; Magnoli, C E; Chiacchiera, S M

    2013-01-01

    A total of 120 pelleted poultry feed samples from Entre Ríos Province, Argentina, were evaluated. The aims were to investigate (1) the presence of relevant toxigenic fungi, as well as to determine the ability to produce aflatoxins (AFs) by Aspergillus section Flavi isolated strains; and (2) the natural co-occurrence of AFs, fumonisins (FBs), gliotoxin, diacetoxyscirpenol (DAS), HT-2 and T-2 toxin by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Total fungal counts were below the established value (1 × 10⁴ CFU g⁻¹). Aspergillus flavus and A. parasiticus were the only aflatoxigenic species isolated. Co-occurrence of fumonisin B₁ (FB₁), HT-2 and T-2 toxin was detected in 100% of the feeds, with mean levels from 4502 to 5813; 6.7 to 21.6 and 19.6 to 30.3 µg kg⁻¹, respectively. A large number of starter samples were co-contaminated with aflatoxin B₁ (AFB₁), FB₁, HT-2 and T-2 toxins. Gliotoxin and DAS were not found in this survey. PMID:24779900

  15. Análisis de la correlación espacio-temporal entre ondas EIT y ondas Moreton

    NASA Astrophysics Data System (ADS)

    Borgazzi, A.; Rovira, M.; Stenborg, G.

    Observaciones de la atmósfera solar en distintas longitudes de onda han demostrado la presencia de fenómenos ondulatorios, tanto a nivel cromosférico como coronal. En el primero de los casos a las ondas observadas se las dió por llamar ondas Moreton, mientras que en el segundo ondas EIT. En el presente trabajo se abordará el estudio de la posible relación causal entre ambos fenómenos ondulatorios. Para concretar dicha meta se hará uso de un conjunto de observaciones del disco solar en Hα (para la determinación y análisis de las ondas Moreton) y en Fe XII (para la determinación y análisis de las ondas EIT). Los observables que se midan serán luego usados para la interpretación física del fenómeno en base a modelos teóricos existentes.

  16. On acoplamento mecânico entre a antena e o transdutor no detector de ondas gravitacionais Mario Schenberg

    NASA Astrophysics Data System (ADS)

    Melo, J. L.; Aguiar, O. D.; Velloso, W. F., Jr.; Lucena, A. U.

    2003-08-01

    O detector de ondas gravitacionais MARIO SCHENBERG consistirá de uma massa esférica de cobre-alumínio de 1150kg resfriada a 4K, sobre a qual serão instalados 6 transdutores de nióbio. Com estes trandutores pretende-se converter um possível sinal de onda gravitacional detectado em sinal elétrico, para tanto é necessário que o acoplamento mecânico entre os transdutores e a massa ressonante seja o maior possível. Isto significa que o transdutor deve ser ressonante na mesma freqüência que a antena (aproximadamente 3200Hz). Neste trabalho foi desenvolvida uma geometria para a estrutura mecânica do trandutor. Isto foi feito criando-se modelos em elementos finitos usando-se o "software" MSC/Nastran. Estes modelos criados foram analisados estaticamente (cálculo de tensões) e dinamicamente (cálculo das freqüências de ressonâncias e seus respectivos modos normais) de maneira a se obter o primeiro modo normal do transdutor em 3200Hz. A partir destes cálculos escolheu-se a melhor geometria para o transdutor. Os próximos passos do trabalho serão: usinar este transdutor em uma barra de nióbio e testá-lo à temperatura ambiente e à baixa temperatura. Após isto, pretende-se testá-lo na própria antena resfriada.

  17. Cristallisation, syncristallisation, et alliages moléculaires entre le lorazépam et l'oxazépam

    NASA Astrophysics Data System (ADS)

    Mascherpa-Corral, D.; Mascherpa, G.; Chauvet, A.

    1993-04-01

    Le polymorphisme et pseudopolymorphisme du lorazépam et oxazépam ont été étudiés par analyse thermique, calorimétrie différentielle à balayage et diffraction de rayons X. Deux formes polymorphes du lorazépam et plusieurs mono et hemisolvates ont été isolés à partir de recristallisation dans divers soivants. Aucun polymorphisme ni solvate n'a été mis en évidence avec l'oxazépam. Les paramètres cristallographiques des phases isolées ont été déterminées. A 160 et 203°C, le lorazépam et l'oxazépam perdent respectivement une molécule d'eau pour donner après réarrangement la quinazolinecarboxaldéhyde correspondante. La syncristallisation des deux benzodiazépines dans le benzène conduit à des alliages moléculaires à miscibilité totale à l'état solide dans tout le domaine de concentration entre l'exazépam el la forme α du lorazépam, elle n'est que partielle avec la forme β. Thermal analysis, differential scanning calorimetry, and X-ray diffraction were carried out to study the polymorphism and pseudopolymorphism of lorazepam and oxazepam. Two polymorphic forms of lorazepam and several mono- or hemisolvates were obtained after recrystallization from various solvents. No polymorphic form or solvate has been found for oxazepam. The crystallographic parameters of these new phases were determined. Lorazepam and oxazepam can lose a molecule of water at 160 and 203°C, respectively, and rearrange to quinazolinecarboxaldehyde. Mixed crystals of the two benzodiazepines, after recrystallization from benzene, lead to molecular alloys with complete solid solubility between oxazepam and the α-form of lorazepam over the whole range of composition but only to partial solubility with the β-form of lorazepam.

  18. L’expression verbale de la douleur chez l’enfant : Comparaison intermodale entre sensation de douleur et manipulation tactile

    PubMed Central

    Bienvenu, Margaux; Jacquet, Denis; Michelutti, Marjolaine; Wood, Chantal

    2011-01-01

    HISTORIQUE: La présente étude se situe dans le contexte de l’expression verbale de la douleur chez l’enfant. Elle porte plus particulièrement sur la dimension qualitative de la sensation de douleur. OBJECTIF: Nous cherchons à repérer les particularités de l’expression verbale relativement à l’aspect qualitatif de la douleur. MÉTHODOLOGIE: La recherche a été menée auprès de 60 patients de quatre à 18 ans ressentant de la douleur, rencontrés dans un hôpital universitaire pédiatrique. Elle confirme en premier lieu l’origine des descripteurs sensoriels de la douleur, qui renvoient aux expériences perceptives passées de l’enfant, non nécessairement liées à la douleur. Ces expériences sont qualifiées de prototypiques, dans la mesure où, bien qu’elles soient liées à des contextes de vie variés, le type de rapport au monde qu’elles provoquent ne varie pas. RÉSULTATS: Dans ce cadre, le pincement, le tiraillement, le tapement, l’écrasement et l’appuiement, le picotement et le serrement constituent chacune des expériences sensorielles et motrices particulières dont la structure de base ne varie pas d’un contexte à l’autre. En second lieu, les résultats obtenus montrent que dès quatre ans, l’enfant est en mesure de comparer, puis de reconnaître une analogie entre une expérience exclusivement tactile et sa sensation de douleur. CONCLUSION: Ces résultats mettent en lumière le rôle primordial du raisonnement analogique dans l’expression verbale de la douleur, ce qui amène à affirmer que le niveau de développement cognitif de l’enfant n’est pas une variable a priori déterminante lorsqu’il s’agit de qualifier sa douleur. PMID:21766069

  19. Half-size me? How calorie and price information influence ordering on restaurant menus with both half and full entrée portion sizes.

    PubMed

    Haws, Kelly L; Liu, Peggy J

    2016-02-01

    Many restaurants are increasingly required to display calorie information on their menus. We present a study examining how consumers' food choices are affected by the presence of calorie information on restaurant menus. However, unlike prior research on this topic, we focus on the effect of calorie information on food choices made from a menu that contains both full size portions and half size portions of entrées. This different focus is important because many restaurants increasingly provide more than one portion size option per entrée. Additionally, we examine whether the impact of calorie information differs depending on whether full portions are cheaper per unit than half portions (non-linear pricing) or whether they have a similar per unit price (linear pricing). We find that when linear pricing is used, calorie information leads people to order fewer calories. This decrease occurs as people switch from unhealthy full sized portions to healthy full sized portions, not to unhealthy half sized portions. In contrast, when non-linear pricing is used, calorie information has no impact on calories selected. Considering the impact of calorie information on consumers' choices from menus with more than one entrée portion size option is increasingly important given restaurant and legislative trends, and the present research demonstrates that calorie information and pricing scheme may interact to affect choices from such menus. PMID:26654889

  20. Relation entre les caractéristiques des table-bancs et les mesures anthropométriques des écoliers au Benin

    PubMed Central

    Falola, Stève Marjelin; Gouthon, Polycarpe; Falola, Jean-Marie; Fiogbe, Michel Armand; Nigan, Issiako Bio

    2014-01-01

    Introduction Le mobilier scolaire et la posture assise en classe sont souvent impliqués dans l'apparition des douleurs rachidiennes, influant de fait sur la qualité des tâches réalisées par les apprenants. Aucune étude n'a encore vérifié le degré d'adéquation entre les caractéristiques du mobilier et celles des écoliers au Bénin. L'objectif de cette étude transversale est donc de déterminer la relation entre les dimensions des table-bancs utilisées en classe et les mesures anthropométriques des écoliers au Bénin. Methods Elle a été réalisée avec un échantillon probabiliste de 678 écoliers, âgés de 4 à 17 ans. Les mesures anthropométriques des écoliers et les mensurations relatives aux longueurs, largeurs et hauteurs des table-bancs ont été mesurées, puis intégrées aux équations proposées dans la littérature. Les pourcentages des valeurs situées hors des limitesacceptables, dérivées de l'application des équations ont été calculés. Results La largeur et la hauteur des table-bancs utilisées par les écoliers étaient plus élevées (p < 0,05) que les valeurs de référence recommandées par les structures officielles de contrôle et de production des mobiliers scolaires au Bénin. Quel que soit le sexe, il y avait une inadéquation entre la largeur du banc et la longueur fesse-poplité, puis entre la hauteur de la table et la distance coude-bancdes écoliers. Conclusion Les résultats suggèrent de prendre en compte l’évolution des mesures anthropométriques des écoliers dans la confection des table-bancs, afin de promouvoir de bonnes postures assises en classe et de réduire le risque de troubles du rachis. PMID:25317232

  1. Amorçage d'une décharge dans le vide entre deux electrodes d'argent ou des alliages argent-nickel

    NASA Astrophysics Data System (ADS)

    Zouache, N.; Lefort, A.

    1997-03-01

    Comparison of the characteristics of an electric are breakdown in vacuum between two silver or silver-nickel alloy electrodes prompted us to study the evolution of the breakdown voltage with electrode separation, with resistance value placed between the anode and the high voltage supply used for the breakdown, and with the effect of conditionning by heating in vacuum. The measurement of the commutation time and delay time, and the observations by a metallographic microscope of the electrodes surfaces after one breakdown, enabled us to evidence the origin of the electric arc for each of the studied materials. La comparaison des caractéristiques de l'amorçage d'un arc électrique dans le vide entre deux électrodes bombées de 8mm de diamètre et de rayon de courbure en surface de 16mm, constituées d'argent ou de son alliage avec le nickel, nous a amené à étudier l'évolution de la tension d'amorçage avec plusieurs paramètres : la distance inter-électrodes, les valeurs de la résistance intercalée entre la source haute tension servant au claquage et les électrodes et le conditionnement par chauffage sous vide des électrodes. La mesure du temps de commutation, du temps de retard et les observations au microscope métallographique de la surface des électrodes après un amorçage donnent des informations sur l'origine de l'arc électrique concernant chaque matériau étudié.

  2. A Process Evaluation of an Efficacious Family-Based Intervention to Promote Healthy Eating: The Entre Familia: Reflejos de Salud Study.

    PubMed

    Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe

    2015-10-01

    Entre Familia: Reflejos de Salud was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker (promotora) model with an entertainment-education component. This process evaluation examined intervention implementation and assessed relationships between implementation factors and dietary change. Participants included 180 mothers randomized to an intervention condition. Process evaluation measures were obtained from participant interviews and promotora notes and included fidelity, dose delivered (i.e., minutes of promotora in-person contact with families, number of promotora home visits), and dose received (i.e., participant use of and satisfaction with intervention materials). Outcome variables included changes in vegetable intake and the use of behavioral strategies to increase dietary fiber and decrease dietary fat intake. Participant satisfaction was high, and fidelity was achieved; 87.5% of families received the planned number of promotora home visits. In the multivariable model, satisfaction with intervention materials predicted more frequent use of strategies to increase dietary fiber (p ≤ .01). Trends suggested that keeping families in the prescribed intervention timeline and obtaining support from other social network members through sharing of program materials may improve changes. Study findings elucidate the relationship between specific intervention processes and dietary changes. PMID:25810469

  3. In Planta mutagenesis determines the functional regions of puroindoline proteins.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    PINA and PINB functionally comprise the wheat (Triticum aestivum L.) Ha locus which controls grain texture and many wheat end-use properties. PINs in their functional forms impart soft texture and a mutation in either PIN is found in all hard wheats. Studies of the PINs mode of action is limited ...

  4. Métastases cutanées vues au laboratoire d'anatomie pathologique à Lomé, Togo entre 2005 et 2014

    PubMed Central

    Darre, Tchin; Saka, Bayaki; Landoh, Dadja Essoya; Mouhari-Toure, Abas; Amegbor, Koffi; Pitché, Palokinam; Napo-Koura, Gado

    2015-01-01

    Introduction L'objectif de cette étude était de documenter le profil épidémiologique et histologique des métastases cutanées vues au laboratoire d'anatomie pathologique (LAP) de Lomé. Méthodes Il s'agissait d'une étude descriptive et transversale portant sur des cas de métastases cutanées observées au LAP du CHU Sylvanus Olympio entre 2005 et 2014. Résultats Au cours de cette période d’étude, nous avons recensé 32 cas de métastases cutanées représentant 3,2% (1005 cas) de l'ensemble des cas de métastases enregistrées au LAP. L’âge moyen des patients atteints de ces métastases cutanées était de 42,6 ans et le sex-ratio (F/H) de 2,2. Sur le plan macroscopique, ces métastases étaient nodulaires dans 15 cas, bourgeonnantes dans 12 cas, ulcéré dans 3 cas et ulcéro-bourgeonnant dans 2 cas. Les types histologiques étaient représentés par les adénocarcinomes (19 cas, 59,4%), les carcinomes épidermoïdes (8 cas, 25%), la maladie de Paget (3 cas, 9,4%), le carcinome à petites cellules du type neuroendocrine (un cas, 3,1%) et le mélanome (un cas, 3,1%). Selon le degré de différenciation, les métastases cutanées étaient bien différenciées dans 14 cas (56%). Les principales localisations de ces métastases cutanées étaient le thorax (11 cas, 34,4%) suivi de l'abdomen (10 cas, 31,3%). Les cancers primitifs étaient surtout d'origine mammaire (14 cas, 43,7%). Conclusion Cette étude montre que les métastases cutanées sont relativement rares et les tumeurs malignes d'origine mammaire sont les tumeurs primitives prédominantes. Avec un pourcentage élevé des formes peu différenciées et celles indifférenciées, l'amélioration du plateau technique du LAP (immunohistochimie) permettra d'accroitre ses capacités diagnostiques. PMID:27047627

  5. A Reappraising of Cosmography: the Interface Between Astronomical and Geographic Studies. (Breton Title: Releitura do Conceito de Cosmografia: a Interface Entre os Estudos Astronômicos e Geográficos.) Una Relectura del Concepto de Cosmografía: la Interfase Entre los Estudios Astronómicos y Geográficos

    NASA Astrophysics Data System (ADS)

    Azevedo Sobreira, Paulo Henrique

    2012-12-01

    The concept of "Cosmography" is in disuse since the 80s of the last century, but the astronomical themes previously discussed in the school subjects of Geography and Cosmography remain in current textbooks. The use of term "Cosmography" was rescued in this research, and the study of its re-signification prompted the appearance of the term Geographic Cosmography. The Geographic Cosmography is a field of studies of the Geography, whose set of knowledge and skills is predominantly scholar. It studies the interface between terrestrial and celestial knowledge, and assigns a geographic significance to them. It examines human and natural relationships with Sidereal Space and its consequences for society and nature. O conceito de "Cosmografia" está em desuso desde os anos 80 do século XX, mas os temas astronômicos anteriormente abordados nas disciplinas escolares de Cosmografia e de Geografia permanecem nos atuais livros didáticos. O uso do termo "Cosmografia" foi resgatado nesta pesquisa e o estudo de sua ressignificação proporcionou o surgimento do termo Cosmografia Geográfica. A Cosmografia Geográfica é um campo de estudos da Geografia, cujo conjunto de conhecimentos e habilidades é predominantemente escolar. Estuda a interface entre os conhecimentos terrestres e os celestes e lhes atribui significância geográfica. Analisa as relações humanas e naturais com o Espaço Sideral e suas consequências para a sociedade e a natureza.

    Aunque el concepto de "Cosmografía" no se usa desde la década de los '80 del siglo pasado, los temas astronómicos que se enseñaban anteriormente en las asignaturas escolares de Cosmografía y de Geografía permanecen en los actuales libros didácticos. El uso del término "Cosmografía" fue rescatado en esta investigación y el estudio de su resignificación proporcionó el surgimiento del término Cosmografía Geográfica. La Cosmografía Geográfica es un campo de estudio de la Geografía, donde el conjunto de conocimientos y habilidades es predominantemente escolar. Estudia la interfase entre los conocimientos terrestres y los celestes, dándoles un significado geográfico. Analiza las relaciones humanas y naturales con el Espacio Sideral y sus consecuencias para la sociedad y la naturaleza.

  6. Etude des phenomenes chimiques au contact entre le bloc cathodique et la barre collectrice d'une cellule d'electrolyse d'aluminium

    NASA Astrophysics Data System (ADS)

    Lebeuf, Martin

    La production d'aluminium est une industrie importante au Québec. Les propriétés de ce métal le vouent à de multiples usages présents et futurs dans le cadre d'une économie moderne durable. Toutefois, le procédé Hall-Héroult est très énergivore et des progrès demeurent donc nécessaires pour en diminuer les coûts financiers et environnementaux. Parmi les améliorations envisageables de la cellule d'électrolyse se trouve le contact entre la cathode et la barre collectrice, qui doit offrir une faible résistivité au passage du courant électrique. En cours d'opération de la cellule, ce contact a tendance à se dégrader, générant des pertes énergétiques significatives. Les causes de cette dégradation, pouvant provenir de phénomènes chimiques, thermiques, mécaniques et/ou électriques, demeurent mal comprises. Le but du présent projet était donc d'étudier les phénomènes chimiques se produisant au contact bloc-barre de la cellule d'électrolyse Hall-Héroult. En premier lieu, un aspect crucial à considérer est la pénétration du bain électrolytique dans la cathode, car des composés de bain atteignent éventuellement la barre collectrice et peuvent y réagir. A cet effet, une méthode novatrice a été développée afin d'étudier les cathodes et la pénétration du bain dans celles-ci à l'aide de la microtomographie à rayons X. Cette méthode rapide et efficace s'est avérée fort utile dans le projet et a un potentiel important pour l'étude future des cathodes et des phénomènes qui s'y produisent. Ensuite, une cellule d'électrolyse rectangulaire à petite échelle a été développée. Plusieurs phénomènes observés 'en industrie sur des autopsies de cellules post-opération et rapportés dans la littérature ont été reproduis avec succès à l'aide de cette cellule expérimentale. Puis, des tests sans électrolyse, ciblant l'effet du bain électrolytique sur l'acier, ont aussi été conçus et complétés afin de ségréger l'influence des différents paramètres en jeu. L'analyse des résultats de l'ensemble de ces tests a permis de constater différents phénomènes au contact bloc-barre, dont la présence systématique de NaF et, surtout, de β-Al 2O3. Outre la carburation inévitable de la barre collectrice, la formation d'une couche Fe-Al a aussi été observée, favorisée par une pénétration rapide du bain électrolytique dans la cathode ainsi que par une composition de bain acide en surface de la barre. Cette couche comportait par ailleurs des cristaux de β-Al 2O3 pouvant nuire à sa conductivité électrique. Ensuite, à des ratios de bain entre 2.5 et 4.9, une mince couche contenant les éléments Al et N peut se former en surface de la barre. Pour un bain très basique (> 6.0), c'est plutôt une couche Na 2O qui a été observée. En conditions d'électrolyse mais sans une pénétration rapide du bain dans la cathode, du Na a pu carrément pénétrer dans la barre collectrice, préférentiellement avec le carbone. De plus, de la corrosion ainsi que des couches de fer et d'oxyde de fer peuvent se former sur la barre et potentiellement dégrader la qualité du contact électrique. Pour la suite des travaux, des mesures de résistivité ainsi que l'analyse des échantillons industriels permettraient d'évaluer l'impact de ces phénomènes sur la qualité du contact. Mots-clés : Électrolyse, aluminium, Hall-Héroult, interface barre-cathode, bain électrolytique.

  7. Un modelo para el control de calidad academica de los textos de instruccion a distancia (A Model for Controlling the Academic Quality of Distance Education Texts).

    ERIC Educational Resources Information Center

    Bolanos-Mora, Guiselle; And Others

    1992-01-01

    In response to the need for a system of control over the academic quality of distance education texts, this article proposes a methodological model based on criteria that evaluate written materials based on their instructional quality, design, and production. A discussion and figures evaluate educational aspects of content, communication,

  8. La efectividad de la educacion a distancia como metodologia en la desarrollo de destrezas de pensamiento (Effectiveness of Distance Education as a Methodology for Developing Thinking Skills).

    ERIC Educational Resources Information Center

    Melendez Alicea, Juan

    1992-01-01

    Presents steps taken in designing, justifying, and implementing an experimental study designed to investigate the effectiveness of distance education as a methodology for developing thinking skills. A discussion reviews major findings of the study by comparing student experiences from multimedia distance education and student experiences from…

  9. El Programa de Educacion a Distancia de la Universidad Nacional Autonoma de Mexico (UNAM) (The Distance Education Program at the National Autonomous University of Mexico (UNAM)).

    ERIC Educational Resources Information Center

    Manilla, Jose Manuel Alvarez

    1996-01-01

    Describes the development of a distance education program at the National Autonomous University of Mexico (UNAM) which will meet several needs: lifelong learning; adult education; service to remote populations; and continuing education for faculty in remote campuses. Provision of large-scale education depends on addressing issues dealing with…

  10. Un modelo para el control de calidad academica de los textos de instruccion a distancia (A Model for Controlling the Academic Quality of Distance Education Texts).

    ERIC Educational Resources Information Center

    Bolanos-Mora, Guiselle; And Others

    1992-01-01

    In response to the need for a system of control over the academic quality of distance education texts, this article proposes a methodological model based on criteria that evaluate written materials based on their instructional quality, design, and production. A discussion and figures evaluate educational aspects of content, communication,…

  11. Pincharse sin infectarse: estrategias para prevenir la infección por el VIH y el VHC entre usuarios de drogas inyectables

    PubMed Central

    MATEU-GELABERT, P.; FRIEDMAN, S.; SANDOVAL, M.

    2011-01-01

    Resumen Objetivo Desde principios de los noventa, en la ciudad de Nueva York se han implementado con éxito programas para reducir la incidencia del virus de la inmunodeficiencia humana (VIH) y, en menor medida, del virus de la hepatitis C (VHC). A pesar de ello, aproximadamente el 70% de los usuario de drogas inyectables (UDI) están infectados por el VHC. Queremos investigar cómo el 30% restante se las ha arreglado para no infectarse. El Staying safe (nombre original del estudio) explora los comportamientos y mecanismos que ayudan a evitar la infección por el VHC y el VIH a largo plazo. Material y métodos Hemos utilizado el concepto de «desviación positiva» aplicado en otros campos de salud pública. Estudiamos las estrategias, prácticas y tácticas de prevención de aquellos UDI que, viviendo en contextos de alta prevalencia, se mantienen sin infectar por VIH y el VHC, a pesar de haberse inyectado heroína durante años. Los resultados preliminares presentados en este artículo incluyen el análisis de las entrevistas realizadas a 25 UDI (17 doble negativos, 3 doble positivos y 5 con infección por el VHC y sin infección por el VIH). Se usaron entrevistas semiestructuradas que exploraban con detalle la historia de vida de los sujetos, incluyendo su consumo de drogas, redes sociales, contacto con instituciones, relaciones sexuales y estrategias de protección y vigilancia. Resultados La intencionalidad es importante para no infectarse, especialmente durante períodos de involución (períodos donde hay un deterioro económico y/o social que llevan al que se inyecta a situaciones de mayor riesgo). Presentamos tres dimensiones independientes de intencionalidad que conllevan comportamientos que pueden ayudar a prevenir la infección: a) evitar «el mono» (síntomas de abstención) asegurando el acceso a la droga; b) «llevarlo bien» para no convertirse en un junkie y así evitar la «muerte social» y la falta de acceso a los recursos, y c) seguir sin infectarse por el VIH (sólo un doble negativo tuvo un amplio conocimiento sobre la hepatitis C). Estas intencionalidades no son mutuamente excluyentes. La presencia de varias refuerza la puesta en práctica a diario de comportamientos que pueden ayudar al que se inyecta a mantenerse libre de infecciones durante años. Algunas prácticas que hemos identificado se implementan en grupo y se comunican de UDI a UDI, de esta manera se extienden entre algunas redes sociales de UDI. Conclusiones Los UDI que permanecen sin infectarse planean e implementan estrategias de prevención en circunstancias donde otros UDI aplican prácticas de riesgo. El mantenimiento de la no infección no es, por lo tanto, un resultado del azar, sino más bien el resultado del esfuerzo (agencia) de los UDI. Investigar y extender estas estrategias y tácticas a través de programas de prevención podría contribuir a la prevención del VIH y el VHC. PMID:21915175

  12. Le renforcement de l'interface entre les services de santé publique et de première ligne : enjeux et pistes de solution

    PubMed Central

    Paquette, Daniel; Reinharz, Daniel

    2009-01-01

    Le développement de liens étroits entre la santé publique et les services cliniques, notamment ceux offerts par les médecins de famille œuvrant en première ligne, est prôné dans tous systèmes de santé occidentaux. On suppose que les collaborations formant une telle interface ont des impacts positifs à la fois sur la qualité des soins, sur le fardeau des maladies et sur l'équité dans le système de santé. Si les acteurs des deux domaines admettent le bien-fondé de l'interface et favorisent en principe son développement, plusieurs barrières nuisent aux collaborations dans la réalité. Or, peu est connu sur ces barrières dans le système de santé québécois. Cette étude vise à répondre à ce manque d'information en étudiant l'interface à partir d'une perspective organisationnelle. Deux cadres conceptuels ont été utilisés, soit la typologie de Lasker (1997) et les archétypes de Hinings et Greenwood (1988). L'analyse met en évidence deux des six formes de collaboration proposées par la typologie utilisée, soit la coordination des services aux individus et la mise à profit des rencontres cliniques pour les fins de la santé publique. Les activités associées à ces formes de collaboration, qui sont importantes eu égard au mandat de la santé publique, comportent un intérêt essentiellement pour la santé publique et sont déterminées en pratique unilatéralement par cette dernière. En outre, le manque de coordination des activités qui impliquent une collaboration avec les médecins constitue un obstacle au développement de telles activités en créant des irritants pour les médecins. Il y a donc, dans le système de santé québécois, des possibilités de développement de l'interface là où la collaboration se fait également au profit du travail clinique et là où elle tient compte des contraintes du milieu clinique. PMID:20436801

  13. Le transfert de connaissances entre les mathematiques et les sciences. Une etude exploratoire aupres d'eleves de 4e secondaire

    NASA Astrophysics Data System (ADS)

    Samson, Ghislain

    2003-06-01

    Au moment ou dans plusieurs pays on travaille a refondre les programmes d'etudes, tant au primaire qu'au secondaire, l'interet pour le transfert renait. Un des concepts fondamentaux en apprentissage consiste en l'habilete a reutiliser de facon consciente et efficace un acquis d'une situation a une autre situation. Cette recherche emane de preoccupations professionnelles au moment ou le chercheur etait enseignant au secondaire. Au cours de ces annees, il lui a ete possible de constater que plusieurs eleves percevaient difficilement les liens presents entre les disciplines mathematiques et scientifiques. Des travaux en psychologie cognitive et plus particulierement selon une perspective du traitement de l'information ont servi de cadre de reference pour evaluer et analyser les capacites de transfert aupres d'eleves de 4e secondaire. Ce cadre de reference permet de formuler le principal objectif qui est de mieux comprendre le processus de transfert chez des eleves en situation de resolution de problemes scientifiques. Cette these s'interesse donc au transfert en tant que phenomene important du processus d'apprentissage au sens de l'integration. La methode de recherche choisie, de nature qualitative, est principalement axee sur l'evaluation de la capacite a transferer des connaissances lors d'une epreuve et d'un entretien. Pour evaluer ce potentiel de transfert, nous avons elabore deux outils: une epreuve en mathematiques et en sciences et un guide d'entretien. Pour la passation de l'epreuve, le chercheur a pu compter sur la collaboration de 130 sujets provenant de deux ecoles. L'entretien complete la prise de donnees avec 13 sujets ayant accepte de poursuivre l'etude. Les donnees recueillies par ces instruments font ensuite l'objet d'une analyse de contenu. En premier lieu, les verbatims de l'epreuve et de l'entretien ont ete transcrits, puis codifies. La correction des reponses fournies pour les problemes resolus s'est faite a partir d'une grille d'analyse qualitative et adaptee de la litterature (Thouin, 1995). Une seconde serie d'analyses permettant de categoriser les reponses selon la typologie des connaissances declaratives, procedurales et conditionnelles complete la prise de donnees. Nos resultats indiquent que les sujets sont tres influences par des elements de surface, principalement lorsqu'il s'agit de problemes auxquels ils ne sont pas habitues. En l'absence de connaissances de base, plusieurs sujets vont tendre vers des propositions de solution "pratico-pratique" provenant de leur vecu: cela nous apparait d'importance d'un point de vue didactique et en matiere de transfert. Lors des entretiens realises un mois plus tard, les sujets ont eprouve de la difficulte a se rappeler le contenu de l'epreuve. Et lorsqu'il y avait un rappel, celui-ci etait superficiel et surtout axe sur le contenu ou le contexte d'un probleme. La plupart des sujets ne pouvait nommer que deux ou trois elements (des problemes en mathematiques, en sciences physiques, le probleme de la fenetre, le probleme du laser, etc.). Nos resultats confirment ce que plusieurs chercheurs (Julo, 1995, Jonnaert et Vander Borght, 1999; Richard et al., 1990) qui s'interessent aux questions de l'apprentissage admettent aujourd'hui: l'eleve ne travaille jamais sur la situation proposee par l'enseignant, mais bien sur la representation qu'il s'en est construite. Au plan methodologique, cette recherche est interessante par la variete des sources de collecte de donnees utilisees, par l'application d'outils methodologiques et d'analyses originaux tires de la recherche et de la pratique. Du cote theorique, il resulte de cette etude une meilleure comprehension du processus de transfert des connaissances mathematiques vers les sciences physiques. Finalement, aux plans didactique et pedagogique, cette recherche alimente la reflexion sur l'apprentissage et l'enseignement des sciences au secondaire. Elle fait ressortir que les mathematiques sont importantes dans la mobilisation de certaines connaissances scientifiques et que l'enseignant peut et devrait jouer un role pour favoriser le transfert.

  14. Association entre les hormones sexuelles, les marqueurs de remodelage osseux et la densité minérale osseuse chez des femmes ménopausées d'origine marocaine (étude transversale)

    PubMed Central

    El Maataoui, Aissam; Biaz, Asmae; El Boukhrissi, Fatima; El Machtani, Si; Dami, Abdellah; Bouhsain, Sanae; Bamou, Youssef; El Maghraoui, Abdellah; Ouzzif, Zhor

    2015-01-01

    Introduction Le présent travail se propose d’étudier la relation entre les hormones sexuelles, notamment l’œstradiol et l'indice de l’œstradiol libre, le sulfate de déhydroépiandrosterone et la sex hormone binding globulin, les marqueurs de remodelage osseux et la densité minérale osseuse chez une population de femmes marocaine ménopausées. Méthodes Il s'agit d'une étude transversale, menée sur une période de 6 mois d'octobre 2012 à fin avril 2013 et ayant fait participer deux cent deux (202). Résultats L’œstradiol et l'indice d’œstradiol libre (IEL) ont montré une corrélation négative respectivement à l'ostéocalcine (OC), à la crosslaps (β-CTX) et l'OC (p<0.001). La sulfate de déhydroepiandrosterone S-DHEA a été corrélée positivement à l'OC (p<0.001), alors que e taux sérique de la sex hormone binding globulin (SHBG) l'a été corrélé à la β-CTX et l'OC (p<0.001). Par ailleurs, une corrélation positive a été établie entre la densité minérale osseuse (DMO) au col de fémur et le poids, l'indice de masse corporelle (IMC), l'IEL et la S-DHEA. Une corrélation négative a été retrouvée entre la DMO au col de fémur d'une part et l’âge, la DDR, la SHBG, la β-CTX et l'OC d'une autre part. Conclusion Le présent travail montre que l'augmentation de l’âge et la diminution de l’œstradiol libre expliquent la diminution de la DMO au niveau du col du fémur, alors que l'augmentation du taux sérique de la SHBG et la diminution du poids expliquent la diminution de la DMO au rachis lombaire. PMID:26848353

  15. Competition entre supraconductivite et magnetisme au voisinage de la transition de Mott dans le conducteur organique quasi-bidimensionnel k-(BEDT-TTF)2copper[N(CN)2]bromine

    NASA Astrophysics Data System (ADS)

    Fournier, David

    Les conducteurs organiques quasi-bidimensionnels kappa-ET2X presentent d'importantes similitudes avec les SCHT telles qu'une phase isolant de Mott, un regime de pseudogap et un etat supraconducteur. L'etude de leurs proprietes apparait donc complementaire. Parmi les interrogations persistantes concernant la physique de ces systemes, l'origine du (ou des) processus exotique d'appariement, responsable de la supraconductivite est le sujet suscitant l'interet le plus marque dans la communaute. L'hypothese d'un mecanisme lie a la proximite d'un etat antiferromagnetique est privilegiee. Une etape importante dans la resolution de cette problematique est l'identification de la symetrie du parametre d'ordre. D'apres de nombreux travaux sur les systemes fortement correles, la sonde ultrasonore, de par sa sensibilite aux excitations de quasiparticule a basse temperature, est consideree comme particulierement adaptee a l'etude de cette propriete. Cependant, son emploi necessite l'utilisation d'un compose metallique a basse temperature et completement supraconducteur. Le compose metallique organique kappa-ET 2Cu[N(CN)2]Br presente toutes les caracteristiques necessaires a l'etude de cette propriete. En effet, il est situe loin de la transition du premier ordre de Mott et est completement supraconducteur. De facon surprenante, ce systeme semble se coupler fortement avec le reseau ce qui augmente significativement la sensibilite de cette sonde aux proprietes du gaz electronique. Cependant, des difficultes techniques importantes, liees a la nature intrinseque de ce materiau, doivent etre surmontees pour proceder a des mesures suivant differentes polarisations. La presente etude a profondement modifie notre comprehension de ce systeme. En effet, ces mesures ont permis de constater que le kappa-ET2Cu[N(CN)2]Br est un compose qui est situe en bordure de la zone de coexistence entre la supraconductivite et le magnetisme, ce qui constitue un resultat totalement inattendu. De plus, la variation judicieuse du cycle thermique s'est averee etre equivalente a une modification de la pression chimique. Cette derniere est modifiee par l'intermediaire d'une relaxation structurale autour de 85 K appelee la transition de verre d'ethylenes. Cela nous a permis de suivre l'evolution de cette coexistence en s'approchant de la transition de premier ordre, et ainsi de statuer sur la competition entre la supraconductivite et le magnetisme ainsi que sur l'existence d'une separation de phase d'ordre macroscopique. De plus, nous avons observe une anisotropie similaire sur les mesures de vitesse ultrasonore entre le regime de pseudogap et la supraconductivite. Ce resultat tend a confirmer l'existence d'une physique commune entre le regime de pseudogap et l'etat supraconducteur. Le regime de pseudogap, encore meconnu a ce jour, est probablement relie a des fluctuations antiferromagnetiques, dont l'origine pourrait etre un emboitement de la surface de Fermi quasi-unidimensionnelle de ce compose, ou bien relie a la proximite de la physique de Mott. Enfin, l'analyse de la symetrie du parametre d'ordre supraconducteur, qui est probablement de type s+d, tend a demontrer que les processus de couplage interplan sont d'une importance cruciale. L'approche theorique de Hubbard purement 2D dans le plan conducteur semble donc insuffisante pour la recherche du mecanisme d'appariement.

  16. Factores socio-económicos asociados a la percepción de situación socioeconómica entre adultos mayores de dos países latinoamericanos

    PubMed Central

    Brenes-Camacho, Gilbert

    2014-01-01

    El objetivo principal del artículo es estudiar la asociación entre la percepción subjetiva sobre la situación económica propia y una serie de medidas objetivas de bienestar socioeconómico –fuentes de ingresos, tenencia de vivienda, nivel educativo y transferencias familiares informales de dinero- entre adultos mayores de dos países Latinoamericanos: México y Costa Rica. Los datos se obtienen de las primeras rondas de dos encuestas sobre envejecimiento: CRELES para Costa Rica y ENASEM para México. La variable dependiente más importante se obtiene de las respuestas a las pregunta “¿Cómo califica su situación económica actual?” en Costa Rica y “¿Diría usted que su situación económica es…?” en México. Para ambas encuestas, las respuestas se codificaron en forma binaria; el código 0 representa las categorías Excelente, Muy buena y Buena, y el código 1 representa a las categorías Regular y Mala. Se encontró que el ingreso por jubilación es un importante determinante de la percepción de bienestar en ambos países. En Costa Rica, el ingreso del cónyuge y la tenencia de vivienda son importantes predictores de la percepción de bienestar, mientras que en México, los ingresos por transferencias están fuertemente asociados con dicha percepción. PMID:25360057

  17. Medicin de los parmetros cosmolgicos q0, ?M, y ??, usando supernovas de Tipo Ia distantes

    NASA Astrophysics Data System (ADS)

    Clocchiatti, A.; High-Z Sne Search Team

    Las supernovas de tipo Ia son una herramienta de gran precisin para la medicin de distancias de inters cosmolgico. Los mtodos recientes de calibracin de su luminosidad intrnseca, que hacen uso de la forma de las curvas de luz en varios colores y permiten diferenciar entre supernovas distantes, intrnsecamente dbiles, u oscurecidas por extincin, reducen la dispersin del mtodo que las asume de magnitud absoluta constante de 0.50 mag a 0.15 mag, e incrementa el valor de la constante de Hubble de ~55 km s-1 Mpc-1, a 65 km s-1 Mpc-1. A partir de la calibracin de las supernovas cercanas, con redshifts menores que 0.1, se pueden obtener distancias precisas a supernovas que explotan a alto redshift. Hemos aplicado estos mtodos a 16 supernovas con 0.16 < Z < 0.97, encontrando que sus distancias son, en promedio, entre 10% y 13% (dependiendo del mtodo empleado) mayores que las que uno esperara en un universo con poca masa (? = 0.2), sin una constante cosmolgica. Todos los mtodos de ajuste de curvas de luz, y seleccin de subgrupos de la muestra de supernovas observadas, favorecen consistentemente modelos del universo que se expanden eternamente y que tienen una constante cosmolgica positiva (?? > 0), y una aceleracin de la expansin al presente (q0 < 0). Hay distintas fuentes de posibles errores sistemticos que merecen ser analizadas, entre ellas: evolucin de la metalicidad y estrellas progenitoras, extincin, bias en la eleccin de la muestra, amplificacin por gravitational lensing, y contaminacin de la muestra. Ninguno de estos efectos alcanza para reconciliar los datos con ?? = 0, o q0 > 0.

  18. Determinação de elementos próprios dos asteróides troianos: comparação entre as teorias semi-analítica e sintética

    NASA Astrophysics Data System (ADS)

    Roig, F.; Beaugé, C.

    2003-08-01

    Além do cálculo semi-analítico de elementos próprios dos asteróides Troianos (Beaugé & Roig 2001, Icarus 153, 391), recentemente foi apresentado um novo conjunto destes elementos próprios determinado através de uma teoria sintética (Knenezevic & Milani 2003, comunicação pessoal). As bases de dados contendo estas determinações estão disponiveis na pagina web do Asteroid Dynamical Site (http://hamilton.dm.unipi.it/cgi-bin/astdys/astibo). Nesta comunicação apresentamos os primeiros resultados de um estudo comparativo entre ambos conjuntos de elementos próprios, analisando suas vantagens e desvantagens, assim como os limites de precisão de cada conjunto. Mostramos que os elementos próprios sintéticos são mais precisos que os smi-analíticos para grandes amplitudes de libração do ângulo s = l-lJup, embora acontece o contrario para os corpos cuja amplitude de libração é muito pequena. Finalmente discutimos a influencia destes erros na determinação de familias de asteroides e da estrutura resonante em torno dos pontos Lagrangeanos L4 e L5.

  19. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires.

    PubMed

    Balán, Iván C; Carballo-Diéguez, Alex; Marone, Rubén O; Pando, María A; Barreda, Victoria; Avila, María M

    2011-03-01

    El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  20. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires

    PubMed Central

    Balán, Iván C.; Carballo-Diéguez, Alex; Marone, Rubén O.; Pando, María A.; Barreda, Victoria; Ávila, María M.

    2011-01-01

    Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  1. Étude physico-chimique des réactions entre oxydes d'azote Application à l'analyse de ces gaz en sortie de systèmes de combustion

    NASA Astrophysics Data System (ADS)

    Leblanc, E.; Jokela, K.; Perier-Camby, L.; Thomas, G.

    1999-05-01

    Analysing gaseous nitrogen oxides emissions at the combustion system outlet (exhaust pipe, central heating, glass kiln,...) are a current environmental topic. Yet, studying these pollutant involves two difficulties : first a great number of NOx do exist, and secondly the system can shift quickly. The objective of this work consists of examining results of literature and studying more specially NO/NO2/O2 system to clarify these problems. For this purpose theoretical and experimental works concerning kinetics and thermodynamics of NOx transformations have been carried out. The NOx maximum starting concentration reaches 1000 ppm in an oxygen-containing atmosphere and with temperature comprised between 25 circC and 1000 circC. These parameters are representative of real combustion conditions. An apparatus has been built to determine both experimental equilibrium and kinetic constants for the reaction 2 NO + O2 = 2 NO2. Rate constants have been measured for temperature lower than 300 circC. Above 300 circC, the catalytic influence of the reactor walls has been clearly established. For each temperature, NOx concentrations at equilibrium give experimental thermodynamic data, in agreement with the theoretical approach. Analyser les émanations d'oxydes d'azote gazeux issus des systèmes de combustion (moteurs automobiles, chauffage urbain, fours de verreries,...) constitue un objectif actuel de recherche concernant l'environnement. L'étude de ces polluants présente une double difficulté. D'une part, ils existent sous de multiples formes, d'autre part de nombreux facteurs viennent influer sur la vitesse de transformation de ces gaz (température, géométrie et nature du réacteur, temps,...). Ce travail a été mené pour effectuer une mise au point des recherches sur le sujet et étudier plus particulièrement aux niveaux thermodynamique et cinétique le mélange gazeux NO/NO2/O2. Un dispositif a été mis au point afin de mesurer expérimentalement les vitesses de réaction pour des paramètres expérimentaux représentatifs des atmosphères générées par les systèmes de combustion (teneur en NOx : 1000 ppm, présence d'oxygène, température comprise entre 25 circC et 1000 circC). Les constantes cinétiques ont ainsi été déterminées pour des températures inférieures à 300 circC. L'influence catalytique de la paroi du réacteur a été mise en évidence au delà de cette température. Les valeurs concernant les équilibres thermodynamiques entre les NOx ont également pu être validées expérimentalement.

  2. L’annonce d’une déficience motrice cérébrale : Une relation de confiance à construire entre les parents, le personnel paramédical et les médecins

    PubMed Central

    Pelchat, Diane; Lefebvre, Hélène; Bouchard, Jean-Marie

    2001-01-01

    RÉSUMÉ : L’annonce d’une déficience motrice cérébrale et des incapacités qui en découlent est une situation difficile à vivre pour les parents et les dispensateurs de soins (personnel paramédical et médecins). Un examen de la documentation médicale démontre que depuis vingt ans, le nombre de parents insatisfaits n’a pas changé. L’étude de type qualitatif et exploratoire, effectuée à la demande de milieux de réadaptation, vise à décrire le processus d’annonce d’un diagnostic de déficience motrice cérébrale (DMC) à partir de l’expérience des différents acteurs en cause et à déterminer les facteurs qui facilitent ou compliquent la relation de confiance. Les résultats indiquent que les parents et les dispensateurs de soins vivent dans deux mondes de perception différents au moment de l’annonce, lesquels se rejoignent difficilement. Les parents sont envahis par le drame qu’ils vivent, tandis que les médecins sont concentrés sur le contenu à transmettre aux parents. Cette annonce provoque une importante incertitude qui bloque la communication entre les partenaires, mais elle pourrait devenir un stimulant à de nouvelles stratégies d’adaptation. PMID:20084263

  3. Distinción Empírica Entre Engagement y Trabajolismo en Enfermeras Hospitalarias de Japón: Efecto Sobre la Calidad del Sueño y el Desempeño Laboral

    PubMed Central

    Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B.

    2016-01-01

    Objetivo El objetivo de este estudio es demostrar la distinción entre engagement y trabajolismo, estudiando su relación con la calidad del sueño y el desempeño laboral. Método Un total de 447 enfermeras de 3 hospitales de Japón fueron entrevistadas mediante un cuestionario autoadministrado que incluía la escala Utrecht (UWES, Utrecht Work Engagement Scale), la Escala de Adicción al Trabajo Holandesa (DUWAS, Dutch Workaholism Scale), preguntas sobre la calidad del sueño (7 ítems) con respecto a (1) dificultad para conciliar el sueño, (2) dificultad para mantener el sueño, (3) despertar temprano por la mañana, (4) dormirse o tomar siestas durante el día, (5) somnolencia diurna excesiva en el trabajo, (6) dificultad para despertarse por la mañana, y (7) despertar cansado en la mañana, y el Cuestionario sobre Salud y Desempeño (CSD) de la Organización Mundial de la Salud. Resultados Los modelos de ecuaciones estructurales demostraron que el engagement se relaciona positivamente con la calidad del sueño y el rendimiento laboral, mientras que el trabajolismo tiene una relación negativa con la calidad del sueño y el desempeño laboral. Conclusión Los resultados indican que el engagement y el trabajolismo son conceptualmente diferentes. El primero tiene una connotación positiva, mientras que el segundo se asocia de manera negativa al bienestar (buena calidad del sueño y buen rendimiento en el trabajo). PMID:26752805

  4. Establishing the Empirical Relationship Between Non-Science Majoring Undergraduate Learners' Spatial Thinking Skills and Their Conceptual Astronomy Knowledge. (Spanish Title: Estableciendo Una Relación Empírica Entre el Razonamiento Espacial de los Estudiantes de Graduación de Carreras no Científicas y su Conocimento Conceptual de la Astronomía.) Estabelecendo Uma Relação Empírica Entre o RacioCínio Espacial dos Estudantes de Graduação EM Carreiras Não Científicas e Seu Conhecimento Conceitual da Astronomia

    NASA Astrophysics Data System (ADS)

    Heyer, Inge; Slater, Stephanie J.; Slater, Timothy F.

    2013-12-01

    The astronomy education community has tacitly assumed that learning astronomy is a conceptual domain resting upon spatial thinking skills. As a first step to formally identify an empirical relationship, undergraduate students in a non-major introductory astronomy survey class at a mediumsized, Ph.D. granting, mid-western US university were given pre- and post-astronomy conceptual diagnostics and spatial reasoning diagnostics, Instruments used were the "Test Of Astronomy Standards" and "What Do You Know?" Using only fully matched data for analysis, our sample consisted of 86 undergraduate non-science majors. Students' normalized gains for astronomy surveys were low at .26 and .13 respectively. Students' spatial thinking was measured using an instrument designed specifically for this study. Correlations between the astronomy instruments' pre- to post-course gain scores and the spatial assessment instrument show moderate to strong relationships suggesting the relationship between spatial reasoning and astronomy ability can explain about 25% of the variation in student achievement. La comunidad de educación en astronomía ha supuesto de forma tácita que el aprendizaje de la astronomía consiste en un dominio conceptual fundamentado en el razonamiento espacial. Como un primer paso para identificar formalmente una relación empírica entre estas dos cosas, utilizamos como muestra los estudantes de graduación de carreras no científicas de un curso experimental en una universidad norteamericana del medioeste de porte mediano con programa de Doctorado em curso, en el cual estos estudiantes se sometieron a un diagnóstico de razonamiento espacial y conceptos astronómicos antes e después del mismo. Las herramientas utilizadas fueron el Test Of Astronomy Standards (TOAST) y el cuestionario What do you know? Utilizando solo los datos completamente consistentes para este análisis, nuestra muestra consistió en 86 estudantes de graduación. Las mejoras, depués de normalizadas, en el desempeño de los estudiantes en estos dos asuntos foram pequenas, 0.26 e 0.13 respectivamente. El razonamiento espacial de los estudiantes fue medido utilizando un instrumento específico desarrollado para este trabaljo. Las correlaciones entre los resultados de los tests astronómicos y este instrumento específico, antes y después del curso mostraron una relación entre moderada y fuerte, sugiriendo que la relación entre el razonamiento espacial y el conocimiento astronómico puede explicar hasta un 25% de la variación em el desempeño de los estudiantes. A comunidade da educação em astronomia tem suposto de forma implícita que o aprendizado da astronomia consiste em um domínio conceitual fundamentado no raciocínio espacial. Como um primeiro passo para identificar formalmente uma relação empírica entre estas duas coisas, utilizamos como amostra os estudantes de graduação de carreiras não científicas de um curso exploratório em uma universidade norte-americana do meio-oeste de médio porte com programa de Doutorado em andamento, onde estes estudantes foram submetidos a um diagnóstico de raciocino espacial e conceitos astronômicos antes e depois do mesmo. As ferramentas utilizadas foram o Test Of Astronomy Standards (TOAST) e o questionário What do you know? Utilizando somente dados completamente consistentes para esta análise, nossa amostra consistiu de 86 estudantes de graduação. As melhoras, depois de normalizadas, do desempenho dos estudantes nos dois quesitos foram pequenas, 0.26 e 0.13 respectivamente. O raciocínio espacial dos estudantes foi medido utilizando um instrumento específico desenhado para este trabalho. As correlações entre os resultados dos testes astronômicos e este instrumento específico antes e depois do curso mostraram uma relação entre moderada e forte, sugerindo que a relação entre o raciocínio espacial e o conhecimento astronômico pode explicar até um 25% na variação no desempenho dos estudantes.

  5. DIMED 86: Discurso dos Media e Ensino a Distancia = Discours des Media et Enseignement a Distance = Media Speech and Distance Teaching. Papers Presented at a Seminar (21st, Algarve, Portugal, March 10-15, 1986).

    ERIC Educational Resources Information Center

    Coelho, Maria Eduarda Leal

    Presentations at this seminar on distance education focused on the different types of speech in multimedia presentations which contribute to the elaboration (simulated or substituted) of a situation involving different relationships. In addition to opening and closing remarks by Marcel de Greve and a final report by the Scientific Committee of…

  6. DIMED 86: Discurso dos Media e Ensino a Distancia = Discours des Media et Enseignement a Distance = Media Speech and Distance Teaching. Papers Presented at a Seminar (21st, Algarve, Portugal, March 10-15, 1986).

    ERIC Educational Resources Information Center

    Coelho, Maria Eduarda Leal

    Presentations at this seminar on distance education focused on the different types of speech in multimedia presentations which contribute to the elaboration (simulated or substituted) of a situation involving different relationships. In addition to opening and closing remarks by Marcel de Greve and a final report by the Scientific Committee of

  7. Chemical compounds effective against the citrus huanglongbing bacterium 'Candidatus Liberibacter asiaticus' in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide, and is threatening the survival of the Floridian citrus industry. Currently, there is no established cure for this century-old and emerging disease. The new antibiotic combination of penicillin and streptomycin (...

  8. In Planta visual monitoring of green fluorescent protein in transgenic rice plants.

    PubMed

    Chung, B C; Kim, J K; Nahm, B H; Lee, C H

    2000-08-31

    The green fluorescent protein (GFP) from the jellyfish Aequorea victoria is a widely used reporter that can be directly visualized in the living cells in both animals and plants. We inserted a synthetic gene (sgfp) encoding a modified form of the GFP into expression vector, Act1-sgfp for the direct expression of GFP which is easily detectable in rice plants. Green fluorescence emitted from GFP could be visualized in calli, dry seeds, roots and seedlings with green shoots of transgenic rice plants. In our visualization system with a charge-coupled device camera, band-pass filters and a light source, the presence of red chlorophyll autofluorescence from chloroplasts did not alter the green fluorescence of GFP. These results demonstrate that GFP could be used as a non-destructive visual selection marker for examining gene expression in transformed calli, dry seeds and young plants. PMID:10987138

  9. IN PLANTA FUNCTIONAL SCREENING OF PHYTOPLASMA GENES: TOWARD IDENTIFICATION OF EFFECTOR PROTEINS INVOLVED IN PATHOGENESIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Candidatus Phytoplasma asteris' and related phytoplasmas are a group of phloem-restricted, cell wall-less bacteria that cause numerous plant diseases worldwide. Despite the recent accomplishments in genome sequencing of two aster yellows phytoplasma strains, knowledge about genes involved in phyto...

  10. Screening a cDNA Library for Protein–Protein Interactions Directly in Planta[W

    PubMed Central

    Lee, Lan-Ying; Wu, Fu-Hui; Hsu, Chen-Tran; Shen, Shu-Chen; Yeh, Hsuan-Yu; Liao, De-Chih; Fang, Mei-Jane; Liu, Nien-Tze; Yen, Yu-Chen; Dokládal, Ladislav; Sýkorová, Eva; Gelvin, Stanton B.; Lin, Choun-Sea

    2012-01-01

    Screening cDNA libraries for genes encoding proteins that interact with a bait protein is usually performed in yeast. However, subcellular compartmentation and protein modification may differ in yeast and plant cells, resulting in misidentification of protein partners. We used bimolecular fluorescence complementation technology to screen a plant cDNA library against a bait protein directly in plants. As proof of concept, we used the N-terminal fragment of yellow fluorescent protein– or nVenus-tagged Agrobacterium tumefaciens VirE2 and VirD2 proteins and the C-terminal extension (CTE) domain of Arabidopsis thaliana telomerase reverse transcriptase as baits to screen an Arabidopsis cDNA library encoding proteins tagged with the C-terminal fragment of yellow fluorescent protein. A library of colonies representing ∼2 × 105 cDNAs was arrayed in 384-well plates. DNA was isolated from pools of 10 plates, individual plates, and individual rows and columns of the plates. Sequential screening of subsets of cDNAs in Arabidopsis leaf or tobacco (Nicotiana tabacum) Bright Yellow-2 protoplasts identified single cDNA clones encoding proteins that interact with either, or both, of the Agrobacterium bait proteins, or with CTE. T-DNA insertions in the genes represented by some cDNAs revealed five novel Arabidopsis proteins important for Agrobacterium-mediated plant transformation. We also used this cDNA library to confirm VirE2-interacting proteins in orchid (Phalaenopsis amabilis) flowers. Thus, this technology can be applied to several plant species. PMID:22623495

  11. The DNA damage response signaling cascade regulates proliferation of the phytopathogenic fungus Ustilago maydis in planta.

    PubMed

    de Sena-Tomás, Carmen; Fernández-Álvarez, Alfonso; Holloman, William K; Pérez-Martín, José

    2011-04-01

    In the phytopathogenic fungus Ustilago maydis, the dikaryotic state dominates the period of growth occurring during the infectious phase. Dikaryons are cells in which two nuclei, one from each parent cell, share a single cytoplasm for a period of time without undergoing nuclear fusion. In fungal cells, maintenance of the dikaryotic state requires an intricate cell division process that often involves the formation of a structure known as the clamp connection as well as the sorting of one of the nuclei to this structure to ensure that each daughter dikaryon inherits a balance of each parental genome. Here, we describe an atypical role of the DNA damage checkpoint kinases Chk1 and Atr1 during pathogenic growth of U. maydis. We found that Chk1 and Atr1 collaborate to control cell cycle arrest during the induction of the virulence program in U. maydis and that Chk1 and Atr1 work together to control the dikaryon formation. These findings uncover a link between a widely conserved signaling cascade and the virulence program in a phytopathogen. We propose a model in which adjustment of the cell cycle by the Atr1-Chk1 axis controls fidelity in dikaryon formation. Therefore, Chk1 and Atr1 emerge as critical cell type regulators in addition to their roles in the DNA damage response. PMID:21478441

  12. In planta changes in protein phosphorylation induced by the plant hormone abscisic acid.

    PubMed

    Kline, Kelli G; Barrett-Wilt, Gregory A; Sussman, Michael R

    2010-09-01

    Abscisic acid (ABA) is a hormone that controls seed dormancy and germination as well as the overall plant response to important environmental stresses such as drought. Recent studies have demonstrated that the ABA-bound receptor binds to and inhibits a class of protein phosphatases. To identify more broadly the phosphoproteins affected by this hormone in vivo, we used (14)N/(15)N metabolic labeling to perform a quantitative untargeted mass spectrometric analysis of the Arabidopsis thaliana phosphoproteome following ABA treatment. We found that 50 different phosphopeptides had their phosphorylation state significantly altered by ABA over a treatment period lasting 5-30 min. Among these changes were increases in phosphorylation of subfamily 2 SNF1-related kinases and ABA-responsive basic leucine zipper transcription factors implicated in ABA signaling by previous in vitro studies. Furthermore, four members of the aquaporin family showed decreased phosphorylation at a carboxy-terminal serine which is predicted to cause closure of the water-transporting aquaporin gate, consistent with ABA's role in ameliorating the effect of drought. Finally, more than 20 proteins not previously known to be involved with ABA were found to have significantly altered phosphorylation levels. Many of these changes are phosphorylation decreases, indicating that an expanded model of ABA signaling, beyond simple phosphatase inhibition, may be necessary. This quantitative proteomics dataset provides a more comprehensive, albeit incomplete, view both of the protein targets whose biochemical activities are likely to be controlled by ABA and of the nature of the emerging phosphorylation and dephosphorylation cascades triggered by this hormone. PMID:20733066

  13. "In planta" regulation of the "Arabidopsis" Ca(2+)/H(+) antiporter CAX1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vacuolar localized Ca(2+)/H(+) exchangers such as "Arabidopsis thaliana" cation exchanger 1 (CAX1) play important roles in Ca(2+) homeostasis. When expressed in yeast, CAX1 is regulated via an N-terminal autoinhibitory domain. In yeast expression assays, a 36 amino acid N-terminal truncation of CAX1...

  14. In Planta Somatic Homologous Recombination Assay Revisited: A Successful and Versatile, but Delicate Tool

    PubMed Central

    Puchta, Holger; Hohn, Barbara

    2012-01-01

    Marker-transgene–dependent lines of Arabidopsis thaliana measuring somatic homologous recombination (SHR) have been available for almost two decades. Here we discuss mechanisms of marker-gene restoration, comment on results obtained using the reporter lines, and stress how caution must be applied to avoid experimental problems or false interpretation in the use of SHR reporter lines. Although theoretically possible, we conclude that explanations other than SHR are unlikely to account for restoration of marker gene expression in the SHR lines when used with appropriate controls. We provide an overview of some of the most important achievements obtained with the SHR lines, give our view of the limitations of the system, and supply the reader with suggestions on the proper handling of the SHR lines. We are convinced that SHR lines are and will remain in the near future a valuable tool to explore the mechanism and influence of external and internal factors on genome stability and DNA repair in plants. PMID:23144182

  15. Regulation and mechanism of potassium release from barley roots: an in planta 42K+ analysis.

    PubMed

    Coskun, Devrim; Britto, Dev T; Kronzucker, Herbert J

    2010-12-01

    Potassium (K(+) ) flux into plant cells is a well-characterized ion transport phenomenon. By contrast, little is known about the mechanisms and regulation of K(+) flux from the cell. Here, we present a radioisotopic analysis of K(+) fluxes from roots of intact barley (Hordeum vulgare), in the context of recent discoveries in the molecular biology and electrophysiology of this process. Plants were labelled with (42)K(+), and kinetics of its release from roots were monitored at low (0.1 mM) or high (1.0 mM) external K concentration, [K(+)](ext), and with the application of channel modulators and nutrient shifts. At 0.1 (but not 1.0) mM [K(+)], where K(+) efflux is thought to be mediated by K(+)-outward-rectifying channels, (42)K(+) efflux was inhibited by the channel blockers barium (Ba(2+)), caesium (Cs(+)), tetraethylammonium (TEA(+)), and lanthanum (La(3+)). Ammonium and nitrate (10 mM) stimulated and inhibited (42)K(+) efflux, respectively, while 10 mM [K(+)](ext) or [Rb(+) ](ext) decreased it. No evidence for the involvement of ATP-binding cassettes, nonselective cation channels, or active K(+)-efflux pumps was found. Our study provides new evidence for the thermodynamic transition between high- and low-affinity transport, from the efflux perspective, identifying the operation of channels at low [K(+)], and the cessation of transmembrane efflux at high [K(+)]. PMID:20731780

  16. Floral Benzenoid Carboxyl Methyltransferases: From in Vitro to in Planta Function

    SciTech Connect

    Effmert,U.; Saschenbrecker, S.; Ross, J.; Negre, F.; Fraser, C.; Noel, J.; Dudareva, N.; Piechulla, B.

    2005-01-01

    Benzenoid carboxyl methyltransferases synthesize methyl esters (e.g., methyl benzoate and methyl salicylate), which are constituents of aromas and scents of many plant species and play important roles in plant communication with the surrounding environment. Within the past five years, eleven such carboxyl methyltransferases were isolated and most of them were comprehensively investigated at the biochemical, molecular and structural level. Two types of enzymes can be distinguished according to their substrate preferences: the SAMT-type enzymes isolated from Clarkia breweri, Stephanotis floribunda, Antirrhinum majus, Hoya carnosa, and Petunia hybrida, which have a higher catalytic efficiency and preference for salicylic acid, while BAMT-type enzymes from A. majus, Arabidopsis thaliana, Arabidopsis lyrata, and Nicotiana suaveolens prefer benzoic acid. The elucidation of C. breweri SAMT's three-dimensional structure allowed a detailed modelling of the active sites of the carboxyl methyltransferases and revealed that the SAM binding pocket is highly conserved among these enzymes while the methyl acceptor binding site exhibits some variability, allowing a classification into SAMT-type and BAMT-type enzymes. The analysis of expression patterns coupled with biochemical characterization showed that these carboxyl methyltransferases are involved either in floral scent biosynthesis or in plant defense responses. While the latter can be induced by biotic or abiotic stress, the genes responsible for floral scent synthesis exhibit developmental and rhythmic expression pattern. The nature of the product and efficiency of its formation in plants depend on the availability of substrates, the catalytic efficiency of the enzyme toward benzoic acid and/or salicylic acid, and the transcriptional, translational, and post-translational regulation at the enzyme level. The biochemical properties of benzenoid carboxyl methyltransferases suggest that the genes involved in plant defenses might represent the ancestor for the presently existing floral genes which during evolution gained different expression profiles and encoded enzymes with the ability to accept structurally similar substrates.

  17. Gene Expression Biomarkers Provide Sensitive Indicators of in Planta Nitrogen Status in Maize[W][OA

    PubMed Central

    Yang, Xiaofeng S.; Wu, Jingrui; Ziegler, Todd E.; Yang, Xiao; Zayed, Adel; Rajani, M.S.; Zhou, Dafeng; Basra, Amarjit S.; Schachtman, Daniel P.; Peng, Mingsheng; Armstrong, Charles L.; Caldo, Rico A.; Morrell, James A.; Lacy, Michelle; Staub, Jeffrey M.

    2011-01-01

    Over the last several decades, increased agricultural production has been driven by improved agronomic practices and a dramatic increase in the use of nitrogen-containing fertilizers to maximize the yield potential of crops. To reduce input costs and to minimize the potential environmental impacts of nitrogen fertilizer that has been used to optimize yield, an increased understanding of the molecular responses to nitrogen under field conditions is critical for our ability to further improve agricultural sustainability. Using maize (Zea mays) as a model, we have characterized the transcriptional response of plants grown under limiting and sufficient nitrogen conditions and during the recovery of nitrogen-starved plants. We show that a large percentage (approximately 7%) of the maize transcriptome is nitrogen responsive, similar to previous observations in other plant species. Furthermore, we have used statistical approaches to identify a small set of genes whose expression profiles can quantitatively assess the response of plants to varying nitrogen conditions. Using a composite gene expression scoring system, this single set of biomarker genes can accurately assess nitrogen responses independently of genotype, developmental stage, tissue type, or environment, including in plants grown under controlled environments or in the field. Importantly, the biomarker composite expression response is much more rapid and quantitative than phenotypic observations. Consequently, we have successfully used these biomarkers to monitor nitrogen status in real-time assays of field-grown maize plants under typical production conditions. Our results suggest that biomarkers have the potential to be used as agronomic tools to monitor and optimize nitrogen fertilizer usage to help achieve maximal crop yields. PMID:21980173

  18. Neonicotinoid insecticides: oxidative stress in planta and metallo-oxidase inhibition.

    PubMed

    Ford, Kevin A; Gulevich, Alexander G; Swenson, Tami L; Casida, John E

    2011-05-11

    Neonicotinoids not only control insect pests but also sometimes independently alter plant growth and response to stress. We find that imidacloprid, thiacloprid, acetamiprid, thiamethoxam, and clothianidin but not nitenpyram and dinotefuran induce foliar lesions and peroxidative damage in soybean ( Glycine max ) seedlings assayed with the 3,3'-diaminobenzidine stain. The chloropyridinyl-carboxylic acid (COOH) but not the -carboxaldehyde (CHO) metabolites induce peroxidative damage but in a different pattern. Surprisingly, the chlorothiazolyl -CHO and -COOH metabolites induce chlorosis but no clear superimposable peroxidative damage or cell death. Four metallo-oxidases known to modulate reactive oxygen species were not sensitive in vitro to the parent neonicotinoid itself but were to several CHO and COOH metabolites and related compounds, with a sensitivity order of CHO > COOH and tyrosinase > xanthine oxidase and aldehyde oxidase > catalase. Although metallo-oxidase inhibition does not correlate overall with lesion formation, it may play an as yet unknown role in plant response to neonicotinoids. PMID:21476569

  19. In planta proteomics and proteogenomics of the biotrophic barley fungal pathogen Blumeria graminis f. sp. hordei.

    PubMed

    Bindschedler, Laurence V; Burgis, Timothy A; Mills, Davinia J S; Ho, Jenny T C; Cramer, Rainer; Spanu, Pietro D

    2009-10-01

    To further our understanding of powdery mildew biology during infection, we undertook a systematic shotgun proteomics analysis of the obligate biotroph Blumeria graminis f. sp. hordei at different stages of development in the host. Moreover we used a proteogenomics approach to feed information into the annotation of the newly sequenced genome. We analyzed and compared the proteomes from three stages of development representing different functions during the plant-dependent vegetative life cycle of this fungus. We identified 441 proteins in ungerminated spores, 775 proteins in epiphytic sporulating hyphae, and 47 proteins from haustoria inside barley leaf epidermal cells and used the data to aid annotation of the B. graminis f. sp. hordei genome. We also compared the differences in the protein complement of these key stages. Although confirming some of the previously reported findings and models derived from the analysis of transcriptome dynamics, our results also suggest that the intracellular haustoria are subject to stress possibly as a result of the plant defense strategy, including the production of reactive oxygen species. In addition, a number of small haustorial proteins with a predicted N-terminal signal peptide for secretion were identified in infected tissues: these represent candidate effector proteins that may play a role in controlling host metabolism and immunity. PMID:19602707

  20. Wide Screening of Phage-Displayed Libraries Identifies Immune Targets in Planta

    PubMed Central

    Rioja, Cristina; Van Wees, Saskia C.; Charlton, Keith A.; Pieterse, Corné M. J.; Lorenzo, Oscar; García-Sánchez, Susana

    2013-01-01

    Microbe-Associated Molecular Patterns and virulence effectors are recognized by plants as a first step to mount a defence response against potential pathogens. This recognition involves a large family of extracellular membrane receptors and other immune proteins located in different sub-cellular compartments. We have used phage-display technology to express and select for Arabidopsis proteins able to bind bacterial pathogens. To rapidly identify microbe-bound phage, we developed a monitoring method based on microarrays. This combined strategy allowed for a genome-wide screening of plant proteins involved in pathogen perception. Two phage libraries for high-throughput selection were constructed from cDNA of plants infected with Pseudomonas aeruginosa PA14, or from combined samples of the virulent isolate DC3000 of Pseudomonas syringae pv. tomato and its avirulent variant avrRpt2. These three pathosystems represent different degrees in the specificity of plant-microbe interactions. Libraries cover up to 2×107 different plant transcripts that can be displayed as functional proteins on the surface of T7 bacteriophage. A number of these were selected in a bio-panning assay for binding to Pseudomonas cells. Among the selected clones we isolated the ethylene response factor ATERF-1, which was able to bind the three bacterial strains in competition assays. ATERF-1 was rapidly exported from the nucleus upon infiltration of either alive or heat-killed Pseudomonas. Moreover, aterf-1 mutants exhibited enhanced susceptibility to infection. These findings suggest that ATERF-1 contains a microbe-recognition domain with a role in plant defence. To identify other putative pathogen-binding proteins on a genome-wide scale, the copy number of selected-vs.-total clones was compared by hybridizing phage cDNAs with Arabidopsis microarrays. Microarray analysis revealed a set of 472 candidates with significant fold change. Within this set defence-related genes, including well-known targets of bacterial effectors, are over-represented. Other genes non-previously related to defence can be associated through this study with general or strain-specific recognition of Pseudomonas. PMID:23372747

  1. In Planta Proteomics and Proteogenomics of the Biotrophic Barley Fungal Pathogen Blumeria graminis f. sp. hordei*

    PubMed Central

    Bindschedler, Laurence V.; Burgis, Timothy A.; Mills, Davinia J. S.; Ho, Jenny T. C.; Cramer, Rainer; Spanu, Pietro D.

    2009-01-01

    To further our understanding of powdery mildew biology during infection, we undertook a systematic shotgun proteomics analysis of the obligate biotroph Blumeria graminis f. sp. hordei at different stages of development in the host. Moreover we used a proteogenomics approach to feed information into the annotation of the newly sequenced genome. We analyzed and compared the proteomes from three stages of development representing different functions during the plant-dependent vegetative life cycle of this fungus. We identified 441 proteins in ungerminated spores, 775 proteins in epiphytic sporulating hyphae, and 47 proteins from haustoria inside barley leaf epidermal cells and used the data to aid annotation of the B. graminis f. sp. hordei genome. We also compared the differences in the protein complement of these key stages. Although confirming some of the previously reported findings and models derived from the analysis of transcriptome dynamics, our results also suggest that the intracellular haustoria are subject to stress possibly as a result of the plant defense strategy, including the production of reactive oxygen species. In addition, a number of small haustorial proteins with a predicted N-terminal signal peptide for secretion were identified in infected tissues: these represent candidate effector proteins that may play a role in controlling host metabolism and immunity. PMID:19602707

  2. Quantification of Sclerotinia homoeocarpa overwintering in planta and detection in commercial seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dollar spot is the most economically important disease of amenity turf grasses in the United States, yet little is known about the source of primary inoculum for this disease. With the exception of a few isolates from the United Kingdom, Sclerotinia homoeocarpa, the causal agent of dollar spot, does...

  3. Chrysanthemyl Diphosphate Synthase Operates in Planta as a Bifunctional Enzyme with Chrysanthemol Synthase Activity*

    PubMed Central

    Yang, Ting; Gao, Liping; Hu, Hao; Stoopen, Geert; Wang, Caiyun; Jongsma, Maarten A.

    2014-01-01

    Chrysanthemyl diphosphate synthase (CDS) is the first pathway-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1′-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate (CPP). Three proteins are known to catalyze this cyclopropanation reaction of terpene precursors. Two of them, phytoene and squalene synthase, are bifunctional enzymes with both prenyltransferase and terpene synthase activity. CDS, the other member, has been reported to perform only the prenyltransferase step. Here we show that the NDXXD catalytic motif of CDS, under the lower substrate conditions prevalent in plants, also catalyzes the next step, converting CPP into chrysanthemol by hydrolyzing the diphosphate moiety. The enzymatic hydrolysis reaction followed conventional Michaelis-Menten kinetics, with a Km value for CPP of 196 μm. For the chrysanthemol synthase activity, DMAPP competed with CPP as substrate. The DMAPP concentration required for half-maximal activity to produce chrysanthemol was ∼100 μm, and significant substrate inhibition was observed at elevated DMAPP concentrations. The N-terminal peptide of CDS was identified as a plastid-targeting peptide. Transgenic tobacco plants overexpressing CDS emitted chrysanthemol at a rate of 0.12–0.16 μg h−1 g−1 fresh weight. We propose that CDS should be renamed a chrysanthemol synthase utilizing DMAPP as substrate. PMID:25378387

  4. Chrysanthemyl diphosphate synthase operates in planta as a bifunctional enzyme with chrysanthemol synthase activity.

    PubMed

    Yang, Ting; Gao, Liping; Hu, Hao; Stoopen, Geert; Wang, Caiyun; Jongsma, Maarten A

    2014-12-26

    Chrysanthemyl diphosphate synthase (CDS) is the first pathway-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1'-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate (CPP). Three proteins are known to catalyze this cyclopropanation reaction of terpene precursors. Two of them, phytoene and squalene synthase, are bifunctional enzymes with both prenyltransferase and terpene synthase activity. CDS, the other member, has been reported to perform only the prenyltransferase step. Here we show that the NDXXD catalytic motif of CDS, under the lower substrate conditions prevalent in plants, also catalyzes the next step, converting CPP into chrysanthemol by hydrolyzing the diphosphate moiety. The enzymatic hydrolysis reaction followed conventional Michaelis-Menten kinetics, with a Km value for CPP of 196 μm. For the chrysanthemol synthase activity, DMAPP competed with CPP as substrate. The DMAPP concentration required for half-maximal activity to produce chrysanthemol was ∼100 μm, and significant substrate inhibition was observed at elevated DMAPP concentrations. The N-terminal peptide of CDS was identified as a plastid-targeting peptide. Transgenic tobacco plants overexpressing CDS emitted chrysanthemol at a rate of 0.12-0.16 μg h(-1) g(-1) fresh weight. We propose that CDS should be renamed a chrysanthemol synthase utilizing DMAPP as substrate. PMID:25378387

  5. Origin and evolution of metal P-type ATPases in Plantae (Archaeplastida)

    PubMed Central

    Hanikenne, Marc; Baurain, Denis

    2013-01-01

    Metal ATPases are a subfamily of P-type ATPases involved in the transport of metal cations across biological membranes. They all share an architecture featuring eight transmembrane domains in pairs of two and are found in prokaryotes as well as in a variety of Eukaryotes. In Arabidopsis thaliana, eight metal P-type ATPases have been described, four being specific to copper transport and four displaying a broader metal specificity, including zinc, cadmium, and possibly copper and calcium. So far, few efforts have been devoted to elucidating the origin and evolution of these proteins in Eukaryotes. In this work, we use large-scale phylogenetics to show that metal P-type ATPases form a homogenous group among P-type ATPases and that their specialization into either monovalent (Cu) or divalent (Zn, Cd…) metal transport stems from a gene duplication that took place early in the evolution of Life. Then, we demonstrate that the four subgroups of plant metal ATPases all have a different evolutionary origin and a specific taxonomic distribution, only one tracing back to the cyanobacterial progenitor of the chloroplast. Finally, we examine the subsequent evolution of these proteins in green plants and conclude that the genes thoroughly characterized in model organisms are often the result of lineage-specific gene duplications, which calls for caution when attempting to infer function from sequence similarity alone in non-model organisms. PMID:24575101

  6. In planta localisation patterns of MADS domain proteins during floral development in Arabidopsis thaliana

    PubMed Central

    Urbanus, Susan L; de Folter, Stefan; Shchennikova, Anna V; Kaufmann, Kerstin; Immink, Richard GH; Angenent, Gerco C

    2009-01-01

    Background MADS domain transcription factors play important roles in various developmental processes in flowering plants. Members of this family play a prominent role in the transition to flowering and the specification of floral organ identity. Several studies reported mRNA expression patterns of the genes encoding these MADS domain proteins, however, these studies do not provide the necessary information on the temporal and spatial localisation of the proteins. We have made GREEN FLUORESCENT PROTEIN (GFP) translational fusions with the four MADS domain proteins SEPALLATA3, AGAMOUS, FRUITFULL and APETALA1 from the model plant Arabidopsis thaliana and analysed the protein localisation patterns in living plant tissues by confocal laser scanning microscopy (CLSM). Results We unravelled the protein localisation patterns of the four MADS domain proteins at a cellular and subcellular level in inflorescence and floral meristems, during development of the early flower bud stages, and during further differentiation of the floral organs. The protein localisation patterns revealed a few deviations from known mRNA expression patterns, suggesting a non-cell autonomous action of these factors or alternative control mechanisms. In addition, we observed a change in the subcellular localisation of SEPALLATA3 from a predominantly nuclear localisation to a more cytoplasmic localisation, occurring specifically during petal and stamen development. Furthermore, we show that the down-regulation of the homeodomain transcription factor WUSCHEL in ovular tissues is preceded by the occurrence of both AGAMOUS and SEPALLATA3 proteins, supporting the hypothesis that both proteins together suppress WUSCHEL expression in the ovule. Conclusion This approach provides a highly detailed in situ map of MADS domain protein presence during early and later stages of floral development. The subcellular localisation of the transcription factors in the cytoplasm, as observed at certain stages during development, points to mechanisms other than transcriptional control. Together this information is essential to understand the role of these proteins in the regulatory processes that drive floral development and leads to new hypotheses. PMID:19138429

  7. In planta reduction of maize seedling stalk lesions by the bacterial endophyte Bacillus mojavensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to autoinfection and alloinfection, maize is susceptible to infection by Fusarium verticillioides resulting in diseases and contamination of maize kernels with the fumonisin mycotoxins. Attempts at controlling this fungus are currently being done with biocontrol agents such as bacteria and this...

  8. In planta distribution and quantification of Asiatic strain of citrus Huanglongbing pathogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing is one of the most devastating diseases caused by an uncultured phloem limited bacterium, Candidatus Liberibacter spp. In this study, a combination of traditional and real-time PCR targeting the putative DNA polymerase and 16S rDNA sequence, respectively, were used to examine the distr...

  9. Stable plasmid vectors for complementation of Xylella fastidiosa mutants in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current understanding of the mechanisms of Pierce’s Disease development has been significantly advanced by molecular genetic studies of the causal agent, Xylella fastidiosa (Xf). Plasmid vectors are an essential tool for studies of bacterial genetics and pathogenesis. However, most commonly used pla...

  10. Auxin transport sites are visualized in planta using fluorescent auxin analogs.

    PubMed

    Hayashi, Ken-ichiro; Nakamura, Shouichi; Fukunaga, Shiho; Nishimura, Takeshi; Jenness, Mark K; Murphy, Angus S; Motose, Hiroyasu; Nozaki, Hiroshi; Furutani, Masahiko; Aoyama, Takashi

    2014-08-01

    The plant hormone auxin is a key morphogenetic signal that controls many aspects of plant growth and development. Cellular auxin levels are coordinately regulated by multiple processes, including auxin biosynthesis and the polar transport and metabolic pathways. The auxin concentration gradient determines plant organ positioning and growth responses to environmental cues. Auxin transport systems play crucial roles in the spatiotemporal regulation of the auxin gradient. This auxin gradient has been analyzed using SCF-type E3 ubiquitin-ligase complex-based auxin biosensors in synthetic auxin-responsive reporter lines. However, the contributions of auxin biosynthesis and metabolism to the auxin gradient have been largely elusive. Additionally, the available information on subcellular auxin localization is still limited. Here we designed fluorescently labeled auxin analogs that remain active for auxin transport but are inactive for auxin signaling and metabolism. Fluorescent auxin analogs enable the selective visualization of the distribution of auxin by the auxin transport system. Together with auxin biosynthesis inhibitors and an auxin biosensor, these analogs indicated a substantial contribution of local auxin biosynthesis to the formation of auxin maxima at the root apex. Moreover, fluorescent auxin analogs mainly localized to the endoplasmic reticulum in cultured cells and roots, implying the presence of a subcellular auxin gradient in the cells. Our work not only provides a useful tool for the plant chemical biology field but also demonstrates a new strategy for imaging the distribution of small-molecule hormones. PMID:25049419

  11. The Papaver rhoeas S determinants confer self-incompatibility to Arabidopsis thaliana in planta.

    PubMed

    Lin, Zongcheng; Eaves, Deborah J; Sanchez-Moran, Eugenio; Franklin, F Christopher H; Franklin-Tong, Vernonica E

    2015-11-01

    Self-incompatibility (SI) is a major genetically controlled system used to prevent inbreeding in higher plants. S determinants regulate allele-specific rejection of "self" pollen by the pistil. SI is an important model system for cell-to-cell recognition and signaling and could be potentially useful for first-generation (F1) hybrid breeding. To date, the transfer of S determinants has used the complementation of orthologs to "restore" SI in close relatives. We expressed the Papaver rhoeas S determinants PrsS and PrpS in Arabidopsis thaliana. This enabled pistils to reject pollen expressing cognate PrpS. Moreover, plants coexpressing cognate PrpS and PrsS exhibit robust SI. This demonstrates that PrsS and PrpS are sufficient for a functional synthetic S locus in vivo. This transfer of novel S determinants into a highly divergent species (>140 million years apart) with no orthologs suggests their potential utility in crop production. PMID:26542572

  12. Heterologous Expression of Glycosyl Hydrolases in planta: A New Departure for Biofuels

    SciTech Connect

    Taylor II, L. E.; Dai, Z.; Decker, S. R.; Brunecky, R.; Adney, W. S.; Ding, S. Y.; Himmel M. E.

    2008-01-01

    The concept of expressing non-plant glycosyl hydrolase genes in plant tissue is nearly two decades old, yet relatively little work in this field has been reported. However, resurgent interest in technologies aimed at enabling processes that convert biomass to sugars and fuels has turned attention toward this intuitive solution. There are several challenges facing researchers in this field, including the development of better and more specifically targeted delivery systems for hydrolytic genes, the successful folding and post-translational modification of heterologous proteins and the development of cost-effective process strategies utilizing these transformed plants. The integration of these concepts, from the improvement of biomass production and conversion characteristics to the heterologous production of glycosyl hydrolases in a high yielding bioenergy crop, holds considerable promise for improving the lignocellulosic conversion of biomass to ethanol and subsequently to fuels.

  13. Heterologous Expression of Glycosyl Hydrolases in planta: A New Departure for Biofuels

    SciTech Connect

    Taylor, Larry E.; Dai, Ziyu; Decker, Stephen R.; Brunecky, Roman; Adney, William S.; Ding, Shi-You; Himmel, Michael E.

    2008-08-01

    The concept of expressing non-plant glycosyl hydrolase genes in plant tissue is less than two decades old, and yet little work in this field has been reported. However, the resurgent interest in technologies aimed at enabling biomass to sugars/fuels processes have again pointed to this intuitive solution. Research challenges in this regard include developing better and more specifically targeted delivery systems for hydrolytic genes, achieving successful folding and post-translational modification of heterologous proteins, and developing cost effective process strategies utilizing these transformed plants. Integration of these concepts, from the improvement of biomass production and conversion characteristics to heterologous production of glycosyl hydrolases in a high yielding bioenergy crop, holds considerable promise for improving the lignocellulosic biomass to ethanol/fuels process.

  14. RT real-time PCR-based quantification of Uromyces fabae in planta.

    PubMed

    Voegele, Ralf T; Schmid, Annette

    2011-09-01

    Quantification of obligate biotrophic parasites has been a long-standing problem in plant pathology. Many attempts have been made to determine how much of a pathogen is present in infected plant tissue. Methods of quantification included scoring disease symptoms, microscopic evaluation, determination of specific compounds like Ergosterol, and lately nucleic acid-based technologies. All of these methods have their drawbacks, and even real-time PCR may not be quantitative if for example the organism of interest has specific and differing numbers of nuclei in different infection structures. We applied reverse transcription (RT) real-time PCR to quantify Uromyces fabae within its host plant Vicia faba. We used three different genes, which have been shown to be constitutively expressed. Our analyses show an exponential increase of fungal material between 4 and 9 days post inoculation and thereafter reaching a steady state of around 45% of total RNA. We also used haustorium-specific genes to determine the amount of haustoria present at each time point. These analyses parallel the development of the whole fungus with the exception of the steady-state level, which is only around 5% of the total RNA. This indicates that RT real-time PCR is a suitable method for quantification of obligate biotrophic parasites, and also for the differentiation of developmental stages. PMID:21707731

  15. Angiogenic activity of latex from Euphorbia tirucalliLinnaeus 1753 (Plantae, Euphorbiaceae).

    PubMed

    Bessa, G; Melo-Reis, P R; Araújo, L A; Mrué, F; Freitas, G B; Brandão, M L; Silva Júnior, N J

    2015-08-01

    To assess the pro-angiogenic activity of Euphorbia tirucalli, commonly known as "avelós" plant, we performed a series of tests by applying an aqueous E. tirucalli latex solution (10 mg/mL) to the chorioallantoic membranes (CAMs) of 80 fertilized chicken eggs incubated in a temperature- and humidity-controlled automatic incubator. The results indicated that the aqueous latex solution increased vascular network formation compared to that with the negative control (p < 0.05) and the inhibitor control (p < 0.05). This suggests that under the experimental conditions tested, the aqueous latex solution induced an inflammatory response leading to neoangiogenesis. PMID:26465734

  16. Dynamic Root Exudation of Sorgoleone and Its in Planta Mechanism of Action

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The oily droplets exuding from the root hairs of sorghum are composed of a 1:1 ratio of sorgoleone and its lipid resorcinol analog. The production and release appear to be suppressed when 15 to 20 µg/mg dry weight accumulates at the tip of the root hairs. However, more exudate is produced followin...

  17. Sistema Planeta-Satélite. Simulación orbital y potenciales gravitatorios

    NASA Astrophysics Data System (ADS)

    Medina, C.; Carrillo, M.

    Se presenta un programa (desarrollado en Quick Basic 4.5) que simula, en tres dimensiones, el movimiento orbital de un satélite (o luna) alrededor de un planeta, al tiempo que calcula y grafica, en un plano, el potencial gravitatorio del sistema en función de la distancia al planeta. Para la simulación orbital, se emplea la matriz de transformación entre el sistema del planeta y el plano orbital. Para el cálculo y graficación del potencial se aplica un desarrollo en serie hasta el segundo orden, que da cuenta del efecto de achatamiento de los polos, en caso de que éste exista. Las longitudes de los ejes del planeta, la masa de éste y del satélite, sus tamaños aparentes, y los parámetros orbitales son introducidos por el usuario.

  18. A Astronomia no Ensino Superior Brasileiro entre 1808 e 1889

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo S.; Videira, Antonio A. P.

    2003-05-01

    Este artigo apresenta os principais eventos ocorridos na história do ensino de astronomia nos cursos superiores que existiram no Brasil desde a chegada da Família Real portuguesa em 1808 até o final do período monárquico. Para compor esse esboço histórico, utilizamos, principalmente, livros didáticos, regulamentos, decretos e leis responsáveis pelas organizações dos conteúdos oferecidos e das carreiras dos responsáveis pela disciplina. Na análise do material empregado, investigamos a presença de concepções filosóficas e científicas, que podem ter norteado os conteúdos disciplinares. Não realizamos nenhuma comparação com o ensino de astronomia em outros países. Concluímos mostrando que o estudo de astronomia, durante o período monárquico, foi mais direcionado para a formação d engenheiros do que astrônomos. Gostaríamos de observar que o presente artigo não tem a pretensão de abordar o assunto de maneira completa e detalhada.

  19. Evaluacion entre colegas profesores (Peer Review of Teachers). ERIC Digest.

    ERIC Educational Resources Information Center

    Hertling, Elizabeth

    This digest in Spanish examines peer review, focusing on how these types of reviews can improve teacher competence. Peer review is often linked to peer assistance, which helps new and veteran teachers improve their knowledge and skills. In peer-review programs, consulting teachers conduct formal evaluations and recommend whether the participating…

  20. Transition quantique entre tats lectroniques de systmes bi-couche

    NASA Astrophysics Data System (ADS)

    Pasquier, Vincent

    The possible phase transitions when two layers at filling factor ?t=1 are gradually separated are studied in this article. In the bosonic case the system should undergo a pairing transition from a Fermi liquid to an incompressible state. In the Fermionic case, the state evolves from an incompressible (1,1,1) state to a Fermi liquid. It is speculated that there is an intermediate phase involving charge two quasiparticles. To cite this article: V. Pasquier, C. R. Physique 3 (2002) 709-715.

  1. Toxicité sérotoninergique résultant d’une interaction médicamenteuse entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine

    PubMed Central

    Charbonneau, Annie

    2013-01-01

    RÉSUMÉ Contexte : Le bleu de méthylène est employé en pratique pour diverses raisons médicales. Des données récentes ont évoqué une interaction potentielle avec les inhibiteurs de la recapture de la sérotonine, pouvant conduire à une toxicité sérotoninergique. Objectif : Décrire le risque de toxicité sérotoninergique associé à l’interaction entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine. Sources de l’information : Les publications pertinentes ont été ciblées systématiquement au moyen des moteurs de recherche MEDLINE (1946 au 21 mars 2013) et Embase (1974 à 2013, semaine 11) en utilisant les mots clés suivants : methylene blue, methylthioninium, monoamine oxidase inhibitors, serotonin reuptake inhibitors et serotonin syndrome. Aucune restriction touchant l’indication du bleu de méthylène ou la langue n’a été appliquée. Les références des publications ont également été analysées. Sélection des études et extraction des données : Dix-huit études de cas et deux séries de cas systématiques ont été sélectionnées. Aucune étude clinique aléatoire n’a encore été publiée. Synthèse des résultats : La première étude de cas à avoir soupçonné une interaction entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine est parue en 2003. Dix-sept autres études de cas décrivant le même type d’interaction ont par la suite été rapportées. Les deux séries de cas ont regroupé les données de quelques 325 parathyroïdectomies où le bleu de méthylène avait été employé comme agent colorant. Les 17 patients qui ont présenté une toxicité du système nerveux central prenaient tous en période préopératoire des inhibiteurs de recapture de la sérotonine. Conclusion : Lorsqu’il est administré en concomitance avec des inhibiteurs de recapture de la sérotonine, le bleu de méthylène peut conduire à une toxicité sérotoninergique à une dose aussi faible que 0,7 mg/kg. En effet, il posséderait des propriétés inhibitrices de la monoamine oxidase A. Des précautions doivent être prises pour éviter cette interaction. PMID:23950608

  2. Etude de la flore bactérienne contaminant les téléphones mobiles avant et après la désinfection: comparaison entre les professionnels soignants de l'hôpital militaire d'instruction Mohammed V de Rabat et les témoins

    PubMed Central

    Uwingabiye, Jean; Moustanfii, Wafaa; Chadli, Meryem; Sekhsokh, Yassine

    2015-01-01

    Introduction L'objectif de notre travail était évaluer la contamination microbienne des téléphones mobiles utilisés par les personnels soignants des différents services de l'hôpital militaire d'instructions Mohammed V de Rabat et la comparer à celui d'une population témoin et aussi démontrer l'efficacité des solutions hydroalcoolique dans la désinfection de ces téléphones mobiles. Méthodes Il s'agit d'une étude descriptive transversale réalisée sur une période de 9 mois entre septembre 2010 et juin 2011, dans le service de bactériologie de l'hôpital militaire d'Instruction Mohammed V. Résultats L’étude bactériologique a été faite sur 240 téléphones mobiles dont 50% provenaient de personnels de sante. Le taux de contamination bactérienne de tous les téléphones mobiles était de 100%. Les cultures des bactéries isolées au niveau des téléphones mobiles du personnel médical étaient plus polymorphes que celles de la population témoin (p=0,028). Parmi 437 bactéries isolées: 223(51%) provenaient de téléphones de personnels de santé et 214(49%) de téléphones de la population témoin avec une différence qui n’était pas statistiquement significative(p>0,05) sauf pour les isolats de Staphylocoque à coagulase négative et Staphylococcus aureus. Les bactéries isolées étaient représentées par: Staphylocoque à coagulase (57,7%), Staphylococcus aureus (18,1%), Corynebacterium sp (18,8%), Bacillus sp (2,3%) et autres (2,2%). La différence entre la prévalence des bactéries isolées selon les services et les fonctions des personnels de santé n’était pas statistiquement significative (p>0,05). La désinfection des téléphones portables par la solution hydroalcoolique a réduit à 99,5% le nombre des colonies. Conclusion Ce travail montre que les téléphones portables pourraient jouer un rôle dans la transmission des infections nosocomiales et communautaires. Dans le cadre de prévention de ces risques, il faut sensibiliser les utilisateurs des téléphones mobiles l'importance du lavage des mains et l'utilisation des solutions hydro alcoolique pour désinfecter aussi bien les téléphones portables que les mains. PMID:26977234

  3. Mutations in the Arabidopsis peroxisomal ABC transporter COMATOSE allow differentiation between multiple functions in planta: insights from an allelic series.

    PubMed

    Dietrich, Daniela; Schmuths, Heike; De Marcos Lousa, Carine; Baldwin, Jocelyn M; Baldwin, Stephen A; Baker, Alison; Theodoulou, Frederica L; Holdsworth, Michael J

    2009-01-01

    COMATOSE (CTS), the Arabidopsis homologue of human Adrenoleukodystrophy protein (ALDP), is required for import of substrates for peroxisomal beta-oxidation. A new allelic series and a homology model based on the bacterial ABC transporter, Sav1866, provide novel insights into structure-function relations of ABC subfamily D proteins. In contrast to ALDP, where the majority of mutations result in protein absence from the peroxisomal membrane, all CTS mutants produced stable protein. Mutation of conserved residues in the Walker A and B motifs in CTS nucleotide-binding domain (NBD) 1 resulted in a null phenotype but had little effect in NBD2, indicating that the NBDs are functionally distinct in vivo. Two alleles containing mutations in NBD1 outside the Walker motifs (E617K and C631Y) exhibited resistance to auxin precursors 2,4-dichlorophenoxybutyric acid (2,4-DB) and indole butyric acid (IBA) but were wild type in all other tests. The homology model predicted that the transmission interfaces are domain-swapped in CTS, and the differential effects of mutations in the conserved "EAA motif" of coupling helix 2 supported this prediction, consistent with distinct roles for each NBD. Our findings demonstrate that CTS functions can be separated by mutagenesis and the structural model provides a framework for interpretation of phenotypic data. PMID:19019987

  4. Health risk assessment of air emissions from a municipal solid waste incineration plant--a case study.

    PubMed

    Cangialosi, Federico; Intini, Gianluca; Liberti, Lorenzo; Notarnicola, Michele; Stellacci, Paolo

    2008-01-01

    A health risk assessment of long-term emissions of carcinogenic and non-carcinogenic air pollutants has been carried out for the municipal solid waste incinerator (MSWI) of the city of Taranto, Italy. Ground level air concentrations and soil deposition of carcinogenic (Polychlorinated Dibenzo-p-Dioxins/Furans and Cd) and non-carcinogenic (Pb and Hg) pollutants have been estimated using a well documented atmospheric dispersion model. Health risk values for air inhalation, dermal contact, soil and food ingestion have been calculated based on a combination of these concentrations and a matrix of environmental exposure factors. Exposure of the surrounding population has been addressed for different release scenarios based on four pollutants, four exposure pathways and two receptor groups (children and adults). Spatial risk distribution and cancer excess cases projected from plant emissions have been compared with background mortality records. Estimated results based on the MSWI emissions show: (1) individual risks well below maximum acceptable levels, (2) very small incremental cancer risk compared with background level. PMID:17611096

  5. In planta expression or delivery of potato aphid Macrosiphum euphorbiae effectors Me10 and Me23 enhances aphid fecundity.

    PubMed

    Atamian, Hagop S; Chaudhary, Ritu; Cin, Valeriano Dal; Bao, Ergude; Girke, Thomas; Kaloshian, Isgouhi

    2013-01-01

    The interactions between aphids and their host plants seem to be analogous to those of plant-microbial pathogens. Unlike microbial pathogen effectors, little is known about aphid effectors and their ability to interfere with host immunity. To date, only three functional aphid effectors have been reported. To identify potato aphid (Macrosiphum euphorbiae) effectors, we developed a salivary gland transcriptome using Illumina technology. We generated 85 million Illumina reads from salivary glands and assembled them into 646 contigs. Ab initio sequence analysis predicted secretion signal peptides in 24% of these sequences, suggesting that they might be secreted into the plant during aphid feeding. Eight of these candidate effectors with secretion signal peptides were functionally characterized using Agrobacterium tumefaciens-mediated transient overexpression in Nicotiana benthamiana. Two candidate effectors, Me10 and Me23, increased aphid fecundity, suggesting their ability to suppress N. benthamiana defenses. Five of these candidate effectors, including Me10 and Me23, were also analyzed in tomato by delivering them through the Pseudomonas syringae type three secretion system. In tomato, only Me10 increased aphid fecundity. This work identified two additional aphid effectors with ability to manipulate the host for their advantage. PMID:23194342

  6. Establishing and fine-tuning an in planta system for potato zebra chip disease research in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have acquired an APHIS-PPQ permit to work on “Candidatus Liberibacter solanacearum” at the USDA-ARS San Joaquin Valley Agricultural Sciences Center in Parlier, California. “Ca. L. solanacearum”, associated with Zebra chip disease (ZCD) of potato. This bacterium is currently unculturable in vitro....

  7. Inhibitory effect of Xenorhabdus nematophila TB on plant pathogens Phytophthora capsici and Botrytis cinerea in vitro and in planta

    PubMed Central

    Fang, Xiangling; Zhang, Manrang; Tang, Qian; Wang, Yonghong; Zhang, Xing

    2014-01-01

    Entomopathogenic bacteria Xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. This study evaluated the inhibitory effect of X. nematophila TB culture on plant pathogens Botrytis cinerea and Phytophthora capsici. The cell-free filtrate of TB culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. The methanol-extracted bioactive compounds (methanol extract) of TB culture also had strong inhibitory effects on mycelial growth and spore germinations of both pathogens. The methanol extract (1000 μg/mL) and cell-free filtrate both showed strong therapeutic and protective effects (>70%) on grey mold both in detached tomato fruits and plants, and leaf scorch in pepper plants. This study demonstrates X. nematophila TB produces antimicrobial metabolites of strong activity on plant pathogens, with great potential for controlling tomato grey mold and pepper leaf scorch and being used in integrated disease control to reduce chemical application. PMID:24599183

  8. A robust and sensitive synthetic sensor to monitor the transcriptional output of the cytokinin signaling network in planta.

    PubMed

    Zürcher, Evelyne; Tavor-Deslex, Deborah; Lituiev, Dmytro; Enkerli, Katalin; Tarr, Paul T; Müller, Bruno

    2013-03-01

    Cytokinins are classic plant hormones that orchestrate plant growth, development, and physiology. They affect gene expression in target cells by activating a multistep phosphorelay network. Type-B response regulators, acting as transcriptional activators, mediate the final step in the signaling cascade. Previously, we have introduced a synthetic reporter, Two Component signaling Sensor (TCS)::green fluorescent protein (GFP), which reflects the transcriptional activity of type-B response regulators. TCS::GFP was instrumental in uncovering roles of cytokinin and deepening our understanding of existing functions. However, TCS-mediated expression of reporters is weak in some developmental contexts where cytokinin signaling has a documented role, such as in the shoot apical meristem or in the vasculature of Arabidopsis (Arabidopsis thaliana). We also observed that GFP expression becomes rapidly silenced in TCS::GFP transgenic plants. Here, we present an improved version of the reporter, TCS new (TCSn), which, compared with TCS, is more sensitive to phosphorelay signaling in Arabidopsis and maize (Zea mays) cellular assays while retaining its specificity. Transgenic Arabidopsis TCSn::GFP plants exhibit strong and dynamic GFP expression patterns consistent with known cytokinin functions. In addition, GFP expression has been stable over generations, allowing for crosses with different genetic backgrounds. Thus, TCSn represents a significant improvement to report the transcriptional output profile of phosphorelay signaling networks in Arabidopsis, maize, and likely other plants that display common response regulator DNA-binding specificities. PMID:23355633

  9. Inhibitory effect of Xenorhabdus nematophila TB on plant pathogens Phytophthora capsici and Botrytis cinerea in vitro and in planta.

    PubMed

    Fang, Xiangling; Zhang, Manrang; Tang, Qian; Wang, Yonghong; Zhang, Xing

    2014-01-01

    Entomopathogenic bacteria Xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. This study evaluated the inhibitory effect of X. nematophila TB culture on plant pathogens Botrytis cinerea and Phytophthora capsici. The cell-free filtrate of TB culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. The methanol-extracted bioactive compounds (methanol extract) of TB culture also had strong inhibitory effects on mycelial growth and spore germinations of both pathogens. The methanol extract (1000 μg/mL) and cell-free filtrate both showed strong therapeutic and protective effects (>70%) on grey mold both in detached tomato fruits and plants, and leaf scorch in pepper plants. This study demonstrates X. nematophila TB produces antimicrobial metabolites of strong activity on plant pathogens, with great potential for controlling tomato grey mold and pepper leaf scorch and being used in integrated disease control to reduce chemical application. PMID:24599183

  10. Phytohormonal networks promote differentiation of fiber initials on pre-anthesis cotton ovules grown in vitro and in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The number of cotton (Gossypium sp.) ovule epidermal cells differentiating into fiber initials is an important factor affecting cotton yield and fiber quality. Despite extensive efforts in determining the molecular mechanisms regulating fiber initial differentiation, only a few genes responsible for...

  11. In planta detection of Xanthomonas axonopodis pv. commiphorae using fyuA and rpoD genes.

    PubMed

    Samanta, Jatindra Nath; Mandal, Kunal

    2013-06-01

    Guggal is tapped for extraction of medicinally important oleo-gum-resin (guggul) by inoculating the stem bark with natural gum suspension containing pathogenic bacterium Xanthomonas axonopodis pv. commiphorae (Xac). The tree dies in the process. In absence of any specific medium for isolation of Xac, it is difficult to assess spread of the pathogen within the plant. A PCR based molecular detection technique usingfyuA and rpoD gene specific primers is described here. The primers amplified products only from Xac and not from host tissues or common saprophytes. The method was sensitive enough to produce positive signals for up to 4.4 bacterial cells or 2 pg target DNA per reaction mixture. However, PCR inhibitors present in plant tissues drastically reduced the limit of detection. A simple overnight incubation of surface sterilised plant tissues in nutrient medium was introduced to increase pathogen titre and to overcome this problem. This technique was successfully used to measure spread of Xac in plant tissues away from the site of inoculation. The pathogen showed preference for acropetal movement and did not spread to 7-8 cm below the site of inoculation till 15 days after inoculation. This suggests possibility to manage the disease through plant surgery. PMID:23926696

  12. Remote sensing of gene expression in Planta: transgenic plants as monitors of exogenous stress perception in extraterrestrial environments

    NASA Technical Reports Server (NTRS)

    Manak, Michael S.; Paul, Anna-Lisa; Sehnke, Paul C.; Ferl, Robert J.

    2002-01-01

    Transgenic arabidopsis plants containing the alcohol dehydrogenase (Adh) gene promoter fused to the green fluorescent protein (GFP) reporter gene were developed as biological sensors for monitoring physiological responses to unique environments. Plants were monitored in vivo during exposure to hypoxia, high salt, cold, and abcissic acid in experiments designed to characterize the utility and responses of the Adh/GFP biosensors. Plants in the presence of environmental stimuli that induced the Adh promoter responded by expressing GFP, which in turn generated a detectable fluorescent signal. The GFP signal degraded when the inducing stimulus was removed. Digital imaging of the Adh/GFP plants exposed to each of the exogenous stresses demonstrated that the stress-induced gene expression could be followed in real time. The experimental results established the feasibility of using a digital monitoring system for collecting gene expression data in real time from Transgenic Arabidopsis Gene Expression System (TAGES) biosensor plants during space exploration experiments.

  13. Proteins with high turnover rate in barley leaves estimated by proteome analysis combined with in planta isotope labeling.

    PubMed

    Nelson, Clark J; Alexova, Ralitza; Jacoby, Richard P; Millar, A Harvey

    2014-09-01

    Protein turnover is a key component in cellular homeostasis; however, there is little quantitative information on degradation kinetics for individual plant proteins. We have used (15)N labeling of barley (Hordeum vulgare) plants and gas chromatography-mass spectrometry analysis of free amino acids and liquid chromatography-mass spectrometry analysis of proteins to track the enrichment of (15)N into the amino acid pools in barley leaves and then into tryptic peptides derived from newly synthesized proteins. Using information on the rate of growth of barley leaves combined with the rate of degradation of (14)N-labeled proteins, we calculate the turnover rates of 508 different proteins in barley and show that they vary by more than 100-fold. There was approximately a 9-h lag from label application until (15)N incorporation could be reliably quantified in extracted peptides. Using this information and assuming constant translation rates for proteins during the time course, we were able to quantify degradation rates for several proteins that exhibit half-lives on the order of hours. Our workflow, involving a stringent series of mass spectrometry filtering steps, demonstrates that (15)N labeling can be used for large-scale liquid chromatography-mass spectrometry studies of protein turnover in plants. We identify a series of abundant proteins in photosynthesis, photorespiration, and specific subunits of chlorophyll biosynthesis that turn over significantly more rapidly than the average protein involved in these processes. We also highlight a series of proteins that turn over as rapidly as the well-known D1 subunit of photosystem II. While these proteins need further verification for rapid degradation in vivo, they cluster in chlorophyll and thiamine biosynthesis. PMID:25082890

  14. In planta production of the highly potent resveratrol analogue pterostilbene via stilbene synthase and O-methyltransferase co-expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stilbenoid phytoalexins such as resveratrol, play an important defense role in several plant species against pathogens such as Botrytis cinerea. In addition to their antimicrobial properties, resveratrol and related stilbenes have also generated considerable interest as nutraceuticals, due to their...

  15. In planta production of the highly potent resveratrol analogue pterostilbene via stilbene synthase and O-methyltransferase co-expression

    SciTech Connect

    Rimando A. M.; Liu C.; Pan, Z.; Polashock, J. J.; Dayan, F. E., Mizuno, C. S.; Snook, M. E.; Baerson, S. R.

    2012-04-01

    Resveratrol and related stilbenes are thought to play important roles in defence responses in several plant species and have also generated considerable interest as nutraceuticals owing to their diverse health-promoting properties. Pterostilbene, a 3,5-dimethylether derivative of resveratrol, possesses properties similar to its parent compound and, additionally, exhibits significantly higher fungicidal activity in vitro and superior pharmacokinetic properties in vivo. Recombinant enzyme studies carried out using a previously characterized O-methyltransferase sequence from Sorghum bicolor (SbOMT3) demonstrated its ability to catalyse the A ring-specific 3,5-bis-O-methylation of resveratrol, yielding pterostilbene. A binary vector was constructed for the constitutive co-expression of SbOMT3 with a stilbene synthase sequence from peanut (AhSTS3) and used for the generation of stably transformed tobacco and Arabidopsis plants, resulting in the accumulation of pterostilbene in both species. A reduced floral pigmentation phenotype observed in multiple tobacco transformants was further investigated by reversed-phase HPLC analysis, revealing substantial decreases in both dihydroquercetin-derived flavonoids and phenylpropanoid-conjugated polyamines in pterostilbene-producing SbOMT3/AhSTS3 events. These results demonstrate the potential utility of this strategy for the generation of pterostilbene-producing crops and also underscore the need for the development of additional approaches for minimizing concomitant reductions in key phenylpropanoid-derived metabolites.

  16. An in planta-expressed polyketide synthase produces (R)-mellein in the wheat pathogen Parastagonospora nodorum.

    PubMed

    Chooi, Yit-Heng; Krill, Christian; Barrow, Russell A; Chen, Shasha; Trengove, Robert; Oliver, Richard P; Solomon, Peter S

    2015-01-01

    Parastagonospora nodorum is a pathogen of wheat that affects yields globally. Previous transcriptional analysis identified a partially reducing polyketide synthase (PR-PKS) gene, SNOG_00477 (SN477), in P. nodorum that is highly upregulated during infection of wheat leaves. Disruption of the corresponding SN477 gene resulted in the loss of production of two compounds, which we identified as (R)-mellein and (R)-O-methylmellein. Using a Saccharomyces cerevisiae yeast heterologous expression system, we successfully demonstrated that SN477 is the only enzyme required for the production of (R)-mellein. This is the first identification of a fungal PKS that is responsible for the synthesis of (R)-mellein. The P. nodorum ΔSN477 mutant did not show any significant difference from the wild-type strain in its virulence against wheat. However, (R)-mellein at 200 μg/ml inhibited the germination of wheat (Triticum aestivum) and barrel medic (Medicago truncatula) seeds. Comparative sequence analysis identified the presence of mellein synthase (MLNS) homologues in several Dothideomycetes and two sodariomycete genera. Phylogenetic analysis suggests that the MLNSs in fungi and bacteria evolved convergently from fungal and bacterial 6-methylsalicylic acid synthases. PMID:25326302

  17. Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta.

    PubMed

    Hu, Sin-Fen; Huang, Yu-Hsin; Lin, Chan-Pin; Liu, Li-Yu Daisy; Hong, Syuan-Fei; Yang, Chiao-Yin; Lo, Hsiao-Feng; Tseng, Ting-Yu; Chen, Wei-Yao; Lin, Shih-Shun

    2015-01-01

    PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches'-broom (AYWB) phytoplasma and Peanut witches'-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies. PMID:26076458

  18. In planta mechanism of action of leptospermone: impact of its physico-chemical properties on uptake, translocation, and metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leptospermone is a natural ß-triketone that specifically inhibits the enzyme p-hydrophyphenylpyruvate dioxygenase, the same molecular target site as that of the commercial herbicide mesotrione. The ß-triketone-rich essential oil of Leptospermum scoparium has both preemergence or postemergence herbi...

  19. An In Planta-Expressed Polyketide Synthase Produces (R)-Mellein in the Wheat Pathogen Parastagonospora nodorum

    PubMed Central

    Krill, Christian; Barrow, Russell A.; Chen, Shasha; Trengove, Robert; Oliver, Richard P.; Solomon, Peter S.

    2014-01-01

    Parastagonospora nodorum is a pathogen of wheat that affects yields globally. Previous transcriptional analysis identified a partially reducing polyketide synthase (PR-PKS) gene, SNOG_00477 (SN477), in P. nodorum that is highly upregulated during infection of wheat leaves. Disruption of the corresponding SN477 gene resulted in the loss of production of two compounds, which we identified as (R)-mellein and (R)-O-methylmellein. Using a Saccharomyces cerevisiae yeast heterologous expression system, we successfully demonstrated that SN477 is the only enzyme required for the production of (R)-mellein. This is the first identification of a fungal PKS that is responsible for the synthesis of (R)-mellein. The P. nodorum ΔSN477 mutant did not show any significant difference from the wild-type strain in its virulence against wheat. However, (R)-mellein at 200 μg/ml inhibited the germination of wheat (Triticum aestivum) and barrel medic (Medicago truncatula) seeds. Comparative sequence analysis identified the presence of mellein synthase (MLNS) homologues in several Dothideomycetes and two sodariomycete genera. Phylogenetic analysis suggests that the MLNSs in fungi and bacteria evolved convergently from fungal and bacterial 6-methylsalicylic acid synthases. PMID:25326302

  20. Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta

    PubMed Central

    Liu, Li-Yu Daisy; Hong, Syuan-Fei; Yang, Chiao-Yin; Lo, Hsiao-Feng; Tseng, Ting-Yu; Chen, Wei-Yao; Lin, Shih-Shun

    2015-01-01

    PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches’-broom (AYWB) phytoplasma and Peanut witches’-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies. PMID:26076458

  1. A straightforward and reliable method for bacterial in planta transcriptomics: application to the Dickeya dadantii/Arabidopsis thaliana pathosystem.

    PubMed

    Chapelle, Emilie; Alunni, Benoît; Malfatti, Pierrette; Solier, Lucie; Pédron, Jacques; Kraepiel, Yvan; Van Gijsegem, Frédérique

    2015-04-01

    Transcriptome analysis of bacterial pathogens is a powerful approach to identify and study the expression patterns of genes during host infection. However, analysis of the early stages of bacterial virulence at the genome scale is lacking with respect to understanding of plant-pathogen interactions and diseases, especially during foliar infection. This is mainly due to both the low ratio of bacterial cells to plant material at the beginning of infection, and the high contamination by chloroplastic material. Here we describe a reliable and straightforward method for bacterial cell purification from infected leaf tissues, effective even if only a small amount of bacteria is present relative to plant material. The efficiency of this method for transcriptomic analysis was validated by analysing the expression profiles of the phytopathogenic enterobacterium Dickeya dadantii, a soft rot disease-causing agent, during the first hours of infection of the model host plant Arabidopsis thaliana. Transcriptome profiles of epiphytic bacteria and bacteria colonizing host tissues were compared, allowing identification of approximately 100 differentially expressed genes. Requiring no specific equipment, cost-friendly and easily transferable to other pathosystems, this method should be of great interest for many other plant-bacteria interaction studies. PMID:25740271

  2. Production and characterization of in planta transiently produced polygalacturanase from Aspergillus niger and its fusions with hydrophobin or ELP tags

    PubMed Central

    2014-01-01

    Background Pectinases play an important role in plant cell wall deconstruction and have potential in diverse industries such as food, wine, animal feed, textile, paper, fuel, and others. The demand for such enzymes is increasing exponentially, as are the efforts to improve their production and to implement their use in several industrial processes. The goal of this study was to examine the potential of producing polygalacturonase I from Aspergillus niger in plants and to investigate the effects of subcellular compartmentalization and protein fusions on its accumulation and activity. Results Polygalacturonase I from Aspergillus niger (AnPGI) was transiently produced in Nicotiana benthamiana by targeting it to five different cellular compartments: apoplast, endoplasmic reticulum (ER), vacuole, chloroplast and cytosol. Accumulation levels of 2.5%, 3.0%, and 1.9% of total soluble protein (TSP) were observed in the apoplast, ER, and vacuole, respectively, and specific activity was significantly higher in vacuole-targeted AnPGI compared to the same enzyme targeted to the ER or apoplast. No accumulation was found for AnPGI when targeted to the chloroplast or cytosol. Analysis of AnPGI fused with elastin-like polypeptide (ELP) revealed a significant increase in the protein accumulation level, especially when targeted to the vacuole where the protein doubles its accumulation to 3.6% of TSP, while the hydrophobin (HFBI) fusion impaired AnPGI accumulation and both tags impaired activity, albeit to different extents. The recombinant protein showed activity against polygalacturonic acid with optimum conditions at pH 5.0 and temperature from 30 to 50°C, depending on its fusion. In vivo analysis of reducing sugar content revealed a higher release of reducing sugars in plant tissue expressing recombinant AnPGI compared to wild type N. benthamiana leaves. Conclusion Our results demonstrate that subcellular compartmentalization of enzymes has an impact on both the target protein accumulation and its activity, especially in the case of proteins that undergo post-translational modifications, and should be taken into consideration when protein production strategies are designed. Using plants to produce heterologous enzymes for the degradation of a key component of the plant cell wall could reduce the cost of biomass pretreatment for the production of cellulosic biofuels. PMID:24970673

  3. The DNA Damage Response Signaling Cascade Regulates Proliferation of the Phytopathogenic Fungus Ustilago maydis in Planta[W

    PubMed Central

    de Sena-Tomás, Carmen; Fernández-Álvarez, Alfonso; Holloman, William K.; Pérez-Martín, José

    2011-01-01

    In the phytopathogenic fungus Ustilago maydis, the dikaryotic state dominates the period of growth occurring during the infectious phase. Dikaryons are cells in which two nuclei, one from each parent cell, share a single cytoplasm for a period of time without undergoing nuclear fusion. In fungal cells, maintenance of the dikaryotic state requires an intricate cell division process that often involves the formation of a structure known as the clamp connection as well as the sorting of one of the nuclei to this structure to ensure that each daughter dikaryon inherits a balance of each parental genome. Here, we describe an atypical role of the DNA damage checkpoint kinases Chk1 and Atr1 during pathogenic growth of U. maydis. We found that Chk1 and Atr1 collaborate to control cell cycle arrest during the induction of the virulence program in U. maydis and that Chk1 and Atr1 work together to control the dikaryon formation. These findings uncover a link between a widely conserved signaling cascade and the virulence program in a phytopathogen. We propose a model in which adjustment of the cell cycle by the Atr1-Chk1 axis controls fidelity in dikaryon formation. Therefore, Chk1 and Atr1 emerge as critical cell type regulators in addition to their roles in the DNA damage response. PMID:21478441

  4. Production of recombinant single chain antibodies (scFv) in vegetatively reproductive Kalanchoe pinnata by in planta transformation.

    PubMed

    Jung, Yuchul; Rhee, Yong; Auh, Chung-Kyoon; Shim, Hyekyung; Choi, Jung-Jin; Kwon, Suk-Tae; Yang, Joo-Sung; Kim, Donggiun; Kwon, Myung-Hee; Kim, Yong-Sung; Lee, Sukchan

    2009-10-01

    We developed an asexual reproductive plant, Kalanchoe pinnata, as a new bioreactor for plant-based molecular farming using a newly developed transformation method. Leaf crenate margins were pin-pricked to infect the plant with the Agrobacterium strain LBA4404 and vacuum infiltration was also applied to introduce the target gene into the plants. Subsequently, the young mother leaf produced new clones at the leaf crenate margins without the need for time- and labor-consuming tissue culture procedures. The average transformation rates were approximately 77 and 84% for pin-prickling and vacuum-infiltration methods, respectively. To functionally characterize an introduced target protein, a nucleic acid hydrolyzing recombinant 3D8 scFv was selected and the plant based 3D8 scFv proteins were purified and analyzed. Based on abzyme analysis, the purified protein expressed with this system had catalytic activity and exhibited all of properties of the protein produced in an E. coli system. This result suggested that vegetatively reproductive K. pinnata can be a novel and potent bioreactor for bio-pharmaceutical proteins. PMID:19688214

  5. A RAPID INFECTION ASSAY FOR ARMILLARIA AND REAL-TIME PCR QUANTITATION OF THE FUNGAL BIOMASS IN PLANTA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Slow and unreliable infection in the greenhouse has been a barrier to research on Armillaria root disease. The existing infection assay takes 7-18 months for detectable infection, during which time the inoculum often dies, resulting in unequal challenge among plants. As symptom expression and mort...

  6. Vascular Streak Dieback of cacao in Southeast Asia and Melanesia: in planta detection of the pathogen and a new taxonomy.

    PubMed

    Samuels, Gary J; Ismaiel, Adnan; Rosmana, Ade; Junaid, Muhammad; Guest, David; McMahon, Peter; Keane, Philip; Purwantara, Agus; Lambert, Smilja; Rodriguez-Carres, Marianela; Cubeta, Marc A

    2012-01-01

    Vascular Streak Dieback (VSD) disease of cacao (Theobroma cacao) in Southeast Asia and Melanesia is caused by a basidiomycete (Ceratobasidiales) fungus Oncobasidium theobromae (syn. =Thanatephorus theobromae). The most characteristic symptoms of the disease are green-spotted leaf chlorosis or, commonly since about 2004, necrotic blotches, followed by senescence of leaves beginning on the second or third flush behind the shoot apex, and blackening of infected xylem in the vascular traces at the leaf scars resulting from the abscission of infected leaves. Eventually the shoot apex is killed and infected branches die. In susceptible cacao the fungus may grow through the xylem down into the main stem and kill a mature cacao tree. Infections in the stem of young plants prior to the formation of the first 3-4 lateral branches usually kill the plant. Basidiospores released from corticioid basidiomata developed on leaf scars or along cracks in the main vein of infected leaves infect young leaves. The pathogen commonly infects cacao but there are rare reports from avocado. As both crops are introduced to the region, the pathogen is suspected to occur asymptomatically in native vegetation. The pathogen is readily isolated but cultures cannot be maintained. In this study, DNA was extracted from pure cultures of O. theobromae obtained from infected cacao plants sampled from Indonesia. The internal transcribed spacer region (ITS), consisting of ITS1, 5.8S ribosomal RNA and ITS2, and a portion of nuclear large subunit (LSU) were sequenced. Phylogenetic analysis of ITS sequences placed O. theobromae sister to Ceratobasidium anastomosis groups AG-A, AG-Bo, and AG-K with high posterior probability. Therefore the new combination Ceratobasidium theobromae is proposed. A PCR-based protocol was developed to detect and identify C. theobromae in plant tissue of cacao enabling early detection of the pathogen in plants. A second species of Ceratobasidium, Ceratobasidium ramicola, identified through ITS sequence analysis, was isolated from VSD-affected cacao plants in Java, and is widespread in diseased cacao collected from Indonesia. PMID:22208598

  7. Development of simple and efficient in planta transformation method for rice (Oryza sativa L.) using Agrobacterium tumefaciens.

    PubMed

    Supartana, Putu; Shimizu, Tsutomu; Shioiri, Hidenari; Nogawa, Masahiro; Nozue, Masayuki; Kojima, Mineo

    2005-10-01

    Seeds of rice (Oryza sativa L. var. Koshihikari) were soaked in water for 2 d. Thereafter, the embryo containing an apical meristem was inoculated with Agrobacterium tumefaciens by piercing a site of the husk overlying the embryonic apical meristem with a needle that had been dipped in an A. tumefaciens inoculum. The inoculated seeds were then grown to maturation (T0 plants) and allowed to pollinate naturally to set seeds (T1 plants) in pots under nonsterile conditions. To examine the transformation by various means, three different strains of A. tumefaciens were used for transformation: an M-21 mutant, which is an avirulent mutant with a Tn5 insertion in the iaaM gene, and two LBA4404 strains each with a different binary vector. Five different lines of evidence were demonstrated the transformation: the altered phenotype and its inheritance by the next generation, histochemical detection of beta-glucuronidase, resistance to hygromycin B, detection of the transgene by PCR and rescue of a plasmid consisting of the integrated T-DNA and the flanking rice genome DNA. Transformation efficiency of T1 plants was estimated to be 40% and 43% by PCR and a histochemical assay of beta-glucuronidase, respectively. PMID:16310727

  8. A visual identification key utilizing both gestalt and analytic approaches to identification of Carices present in North America (Plantae, Cyperaceae)

    PubMed Central

    2013-01-01

    Abstract Images are a critical part of the identification process because they enable direct, immediate and relatively unmediated comparisons between a specimen being identified and one or more reference specimens. The Carices Interactive Visual Identification Key (CIVIK) is a novel tool for identification of North American Carex species, the largest vascular plant genus in North America, and two less numerous closely-related genera, Cymophyllus and Kobresia. CIVIK incorporates 1288 high-resolution tiled image sets that allow users to zoom in to view minute structures that are crucial at times for identification in these genera. Morphological data are derived from the earlier Carex Interactive Identification Key (CIIK) which in turn used data from the Flora of North America treatments. In this new iteration, images can be viewed in a grid or histogram format, allowing multiple representations of data. In both formats the images are fully zoomable. PMID:24723777

  9. Binary 2in1 Vectors Improve in Planta (Co)localization and Dynamic Protein Interaction Studies1[OPEN

    PubMed Central

    Hecker, Andreas; Wallmeroth, Niklas; Peter, Sébastien; Blatt, Michael R.

    2015-01-01

    Fluorescence-based protein-protein interaction techniques are vital tools for understanding in vivo cellular functions on a mechanistic level. However, only under the condition of highly efficient (co)transformation and accumulation can techniques such as Förster resonance energy transfer (FRET) realize their potential for providing highly accurate and quantitative interaction data. FRET as a fluorescence-based method unifies several advantages, such as measuring in an in vivo environment, real-time context, and the ability to include transient interactions as well as detecting the mere proximity of proteins. Here, we introduce a novel vector set that incorporates the benefit of the recombination-based 2in1 cloning system with the latest state-of-the-art fluorescent proteins for optimal coaccumulation and FRET output studies. We demonstrate its utility across a range of methods. Merging the 2in1 cloning system with new-generation FRET fluorophore pairs allows for enhanced detection, speeds up the preparation of clones, and enables colocalization studies and the identification of meaningful protein-protein interactions in vivo. PMID:25971551

  10. [In Process Citation].

    PubMed

    Daponte Codina, A; Bolivar Muñoz, J; Sánchez-Cantalejo, E; Mateo-Rodríguez, I; Babio, G; Romo-Avilés, N; Rosell-Ortiz, F; Grupo de Estudio de Género Y Enfermedades Cardiovasculares, G

    2016-01-01

     RESUMEN              Fundamento. Identificar factores asociados a la demora prehospitalaria en personas que han tenido un síndrome coronario agudo             Método. Se estudiaron mediante encuesta pacientes ingresados por síndrome coronario agudo en los 33 hospitales públicos andaluces, obteniéndose información sobre diferentes tipos de variables: socio-demográficas, contextuales, clínicas, percepción, actuaciones, y transporte. Se aplicaron modelos de regresión logística multivariante para calcular las odds ratio para la demora.             Resultados. De los 1.416 pacientes en total, más de la mitad tuvieron una demora superior a la hora. Se asocia a la distancia al hospital y al medio de transporte: cuando el evento ocurre en la misma ciudad del hospital, utilizar medios propios aumenta la demora, odds ratio= 1,51 (1,02-2,23);  si la distancia es entre 1-25 kilómetros, no hay una diferencia entre medios propios y ambulancia, odds ratio = 1,41 y odds ratio = 1,43 respectivamente; y cuando supera los25 kilómetros la ambulancia implica mayor demora, odds ratio = 3,13 y odds ratio = 2,20 respectivamente. Además, la sintomatología típica reduce la demora entre los hombres, pero la aumenta entre las mujeres. Asimismo, no darle importancia, esperar a la resolución de los síntomas, buscar atención sanitaria diferente a urgencias hospitalarias o al 061, tener antecedentes, encontrarse fuera de la vivienda habitual, y tener ingresos menores de 1.500 euros aumentan la demora. Tener síntomas respiratorios la reduce.             Conclusiones. La demora prehospitalaria no se ajusta a las recomendaciones sanitarias, asociándose al  entorno físico y social, a factores clínicos, y de percepción y actitudinales de los sujetos.              Palabras clave. Síndrome coronario agudo. Demora prehospitalaria. Género. Servicios de emergencias sanitarias. Desigualdades. PMID:27125609

  11. Motivation Conditions in a Foreign Language Reading Comprehension Course Offering Both a Web-Based Modality and a Face-to-Face Modality (Las condiciones de motivación en un curso de comprensión de lectura en lengua extranjera (LE) ofrecido tanto en la modalidad presencial como en la modalidad a distancia en la web)

    ERIC Educational Resources Information Center

    Lopera Medina, Sergio

    2014-01-01

    Motivation plays an important in role in education. Based on the ten macro-strategies proposed by Dörnyei and Csizér (1998), this article analyzes the motivation conditions in a foreign language reading comprehension course using both a web-based modality and a face-to-face modality. A case study was implemented as the primary research method, and…

  12. Teaching Reading Comprehension in English in a Distance Web-Based Course: New Roles for Teachers (La enseñanza de la comprensión de lectura en inglés en un curso a distancia en la red: nuevos roles para los docentes)

    ERIC Educational Resources Information Center

    Muñoz Marín, Jorge Hugo; González Moncada, Adriana

    2010-01-01

    Distance web-based learning is a popular strategy in ELT teaching in Colombia. Despite of the growth of experiences, there are very few studies regarding teachers' participation in these courses. This paper reports preliminary findings of an on-going study aiming at exploring the roles that a teach er plays in an EFL reading comprehension…

  13. Courtship behavior of different wild strains of Ceratitis Capitata (Diptera: Tephritidae)

    SciTech Connect

    Briceno, D.; Eberhard, W.; Vilardi, J.; Cayol, J.-P.; Shelly, T.

    2007-03-15

    This study documents differences in the courtship behavior of wild strains of Ceratitis capitata (Wiedemann) from Madeira (Portugal), Hawaii (U.S.A.), Costa Rica, and Patagonia (Argentina). Some traits showed large variations and others substantial overlaps. The angle at which the male faced toward the female at the moment of transition from continuous wing vibration and intermittent buzzing changed very little during the course of courtship in all strains, but males from Madeira tended to face more directly toward the female than other males. Females tended to look more, and more directly, toward the males as courtship progressed in all strains. The distance between male and female tended to decrease as courtship proceeded in all strains, but the distances at which males initiated continuous vibration, intermittent buzzing, and jumped onto the female were relatively less variable between strains, except for the strain from Costa Rica. Flies of Madeira courted for longer and the male moved his head and buzzed his wings longer than the other strains. (author) [Spanish] Este estudio documenta diferencias en el comportamiento de cortejo de cepas silvestres de Ceratitis capitata (Wied.) provenientes de Madeira (Portugal), Hawaii (Estados Unidos de Norte America), Costa Rica y Patagonia (Argentina). Algunas caracteristicas mostraron grandes variaciones y traslape substancial. Los angulos a los cuales los machos miraron hacia las hembras cambiaron muy poco en el momento de la transicion de la vibracion continua al zumbido intermitente durante el curso del cortejo en todo las cepas, pero los machos de Madeira tendieron a enfrentar mas directamente a la hembra que otros machos. Los angulos de las hembras disminuyeron claramente durante el cortejo en todas las cepas. La distancia entre el macho y la hembra tendio a disminuir conforme el cortejo continuaba en todas las cepas, pero las distancias a las cuales los machos iniciaron la vibracion continua, el zumbido intermitente, y el salto sobre la hembra eran relativamente menos variables entre cepas excepto la cepa de Costa Rica. Moscas de Madeira cortejaron mas tiempo y el macho moviosu cabeza y zumbaba sus alas mas prolongadamente que las otras cepas. (author)

  14. Overview of Spanish and Latin American Distance Higher Education.

    ERIC Educational Resources Information Center

    Garcia Garrido, Jose Luis

    1991-01-01

    Provides a brief overview of Spanish and Latin American distance education programs for higher education and describes the three most important institutions: (1) the Spanish UNED (Universidad Nacional de Educacion a Distancia); (2) the Costa Rican UNED (Universidad Estatal a Distancia); and (3) the Venezuelan UNA (Universidad Nacional Abierta).…

  15. Overview of Spanish and Latin American Distance Higher Education.

    ERIC Educational Resources Information Center

    Garcia Garrido, Jose Luis

    1991-01-01

    Provides a brief overview of Spanish and Latin American distance education programs for higher education and describes the three most important institutions: (1) the Spanish UNED (Universidad Nacional de Educacion a Distancia); (2) the Costa Rican UNED (Universidad Estatal a Distancia); and (3) the Venezuelan UNA (Universidad Nacional Abierta).

  16. Transient Co-Expression of Post-Transcriptional Gene Silencing Suppressors for Increased in Planta Expression of a Recombinant Anthrax Receptor Fusion Protein

    PubMed Central

    Arzola, Lucas; Chen, Junxing; Rattanaporn, Kittipong; Maclean, James M.; McDonald, Karen A.

    2011-01-01

    Potential epidemics of infectious diseases and the constant threat of bioterrorism demand rapid, scalable, and cost-efficient manufacturing of therapeutic proteins. Molecular farming of tobacco plants provides an alternative for the recombinant production of therapeutics. We have developed a transient production platform that uses Agrobacterium infiltration of Nicotiana benthamiana plants to express a novel anthrax receptor decoy protein (immunoadhesin), CMG2-Fc. This chimeric fusion protein, designed to protect against the deadly anthrax toxins, is composed of the von Willebrand factor A (VWA) domain of human capillary morphogenesis 2 (CMG2), an effective anthrax toxin receptor, and the Fc region of human immunoglobulin G (IgG). We evaluated, in N. benthamiana intact plants and detached leaves, the expression of CMG2-Fc under the control of the constitutive CaMV 35S promoter, and the co-expression of CMG2-Fc with nine different viral suppressors of post-transcriptional gene silencing (PTGS): p1, p10, p19, p21, p24, p25, p38, 2b, and HCPro. Overall, transient CMG2-Fc expression was higher on intact plants than detached leaves. Maximum expression was observed with p1 co-expression at 3.5 days post-infiltration (DPI), with a level of 0.56 g CMG2-Fc per kg of leaf fresh weight and 1.5% of the total soluble protein, a ten-fold increase in expression when compared to absence of suppression. Co-expression with the p25 PTGS suppressor also significantly increased the CMG2-Fc expression level after just 3.5 DPI. PMID:21954339

  17. Artemisinin production in Artemisia annua: studies in planta and results of a novel delivery method for treating malaria and other neglected diseases

    PubMed Central

    Arsenault, Patrick R.; Covello, Patrick S.; McMickle, Anthony; Teoh, Keat H.; Reed, Darwin W.

    2010-01-01

    Artemisia annua L. produces the sesquiterpene lactone, artemisinin, a potent antimalarial drug that is also effective in treating other parasitic diseases, some viral infections and various neoplasms. Artemisinin is also an allelopathic herbicide that can inhibit the growth of other plants. Unfortunately, the compound is in short supply and thus, studies on its production in the plant are of interest as are low cost methods for drug delivery. Here we review our recent studies on artemisinin production in A. annua during development of the plant as it moves from the vegetative to reproductive stage (flower budding and full flower formation), in response to sugars, and in concert with the production of the ROS, hydrogen peroxide. We also provide new data from animal experiments that measured the potential of using the dried plant directly as a therapeutic. Together these results provide a synopsis of a more global view of regulation of artemisinin biosynthesis in A. annua than previously available. We further suggest an alternative low cost method of drug delivery to treat malaria and other neglected tropical diseases. PMID:21643453

  18. Phylogenetic Analysis of Downy Mildew Pathogens of Opium Poppy and PCR-Based In Planta and Seed Detection of Peronospora arborescens.

    PubMed

    Landa, Blanca B; Montes-Borrego, Miguel; Muñoz-Ledesma, Francisco J; Jiménez-Díaz, Rafael M

    2007-11-01

    ABSTRACT Severe downy mildew diseases of opium poppy (Papaver somniferum) can be caused by Peronospora arborescens and P. cristata, but differentiating between the two pathogens is difficult because they share morphological features and a similar host range. In Spain, where severe epidemics of downy mildew of opium poppy have occurred recently, the pathogen was identified as P. arborescens on the basis of morphological traits. In this current study, sequence homology and phylogenetic analyses of the internal transcribed spacer regions (ITS) of the ribosomal DNA (rDNA) were carried out with DNA from P. arborescens and P. cristata from diverse geographic origins, which suggested that only P. arborescens occurs in cultivated Papaver somniferum in Spain. Moreover, analyses of the rDNA ITS region from 27 samples of downy-mildew-affected tissues from all opium-poppy-growing regions in Spain showed that genetic diversity exists within P. arborescens populations in Spain and that these are phylogenetically distinct from P. cristata. P. cristata instead shares a more recent, common ancestor with a range of Peronospora species that includes those found on host plants that are not members of the Papaveraceae. Species-specific primers and a PCR assay protocol were developed that differentiated P. arborescens and P. cristata and proved useful for the detection of P. arborescens in symptomatic and asymptomatic opium poppy plant parts. Use of these primers demonstrated that P. arborescens can be transmitted in seeds and that commercial seed stocks collected from crops with high incidence of the disease were frequently infected. Field experiments conducted in microplots free from P. arborescens using seed stocks harvested from infected capsules further demonstrated that transmission from seedborne P. arborescens to opium poppy plants can occur. Therefore, the specific-PCR detection protocol developed in this study can be of use for epidemiological studies and diagnosing the pathogen in commercial seed stocks; thus facilitating the sanitary control of the disease and avoidance of the pathogen distribution in seeds. PMID:18943506

  19. The Pratylenchus penetrans Transcriptome as a Source for the Development of Alternative Control Strategies: Mining for Putative Genes Involved in Parasitism and Evaluation of in planta RNAi

    PubMed Central

    Vieira, Paulo; Eves-van den Akker, Sebastian; Verma, Ruchi; Wantoch, Sarah; Eisenback, Jonathan D.; Kamo, Kathryn

    2015-01-01

    The root lesion nematode Pratylenchus penetrans is considered one of the most economically important species within the genus. Host range studies have shown that nearly 400 plant species can be parasitized by this species. To obtain insight into the transcriptome of this migratory plant-parasitic nematode, we used Illumina mRNA sequencing analysis of a mixed population, as well as nematode reads detected in infected soybean roots 3 and 7 days after nematode infection. Over 140 million paired end reads were obtained for this species, and de novo assembly resulted in a total of 23,715 transcripts. Homology searches showed significant hit matches to 58% of the total number of transcripts using different protein and EST databases. In general, the transcriptome of P. penetrans follows common features reported for other root lesion nematode species. We also explored the efficacy of RNAi, delivered from the host, as a strategy to control P. penetrans, by targeted knock-down of selected nematode genes. Different comparisons were performed to identify putative nematode genes with a role in parasitism, resulting in the identification of transcripts with similarities to other nematode parasitism genes. Focusing on the predicted nematode secreted proteins found in this transcriptome, we observed specific members to be up-regulated at the early time points of infection. In the present study, we observed an enrichment of predicted secreted proteins along the early time points of parasitism by this species, with a significant number being pioneer candidate genes. A representative set of genes examined using RT-PCR confirms their expression during the host infection. The expression patterns of the different candidate genes raise the possibility that they might be involved in critical steps of P. penetrans parasitism. This analysis sheds light on the transcriptional changes that accompany plant infection by P. penetrans, and will aid in identifying potential gene targets for selection and use to design effective control strategies against root lesion nematodes. PMID:26658731

  20. SECONDARY METABOLITE PRODUCTION BY THE FUNGAL PATHOGEN EUTYPA LATA: ANALYSIS OF EXTRACTS FROM GRAPEVINE CULTURES AND DETECTION OF THOSE METABOLITES IN PLANTA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutypa dieback of grapevines is caused by the fungal pathogen Eutypa lata and reduces vineyard longevity worldwide. Early detection could reduce losses due to this disease, so our aim was to identify acetylenic phenol metabolites of E. lata that could prove suitable as chemical markers in an early d...

  1. Species-specific ITS primers for the identification of Picoa juniperi and Picoa lefebvrei and using nested-PCR for detection of P. juniperi in planta.

    PubMed

    Jamali, Samad; Banihashemi, Zia

    2013-10-01

    Desert truffles, hypogeous Pezizales (Ascomycota), are difficult to identify due to evolutionary convergence of morphological characters among taxa that share a similar habitat and mode of spore dispersal. Also, during their symbiotic phase, these are barely distinguishable morphologically, and molecular probes are needed for their identification. We have developed a PCR-based method for the identification of Picoa juniperi and Picoa lefebvrei based on internal transcribed spacers of rDNA. Two PCR primers specific for P. lefebvrei (FLE/RLE) and two specific for P. juniperi (FJU/RJU) were designed. A collection of samples from different geographical areas representing diversity of these species were examined for unique regions of internal transcribed spacers 1, 2 and 5.8S gene of rDNA (ITS) compared to other closely related species. Annealing temperatures and extension times were optimized for each set of primers for maximum specificity and efficiency. They proved to be efficient to specifically detect the presence of P. juniperi and P. lefebvrei by PCR and neither set amplified purified DNA from other truffle species as well as some ascomycetous fungi. The partial small subunit of ribosomal DNA genes of P. juniperi were amplified with the genomic DNA extracted from Helianthemum ledifolium var. ledifolium roots by nested polymerase chain reaction (PCR) using the universal fungal primer pair ITS1/ITS4 and specific primer pair FTC/RTC, which was designed based on internal transcribed spacer 1, 2 and 5.8S gene of rDNA sequences of P juniperi. The nested-PCR was sensitive enough to re-amplify the direct-PCR product, resulting in a DNA fragment of 426 bp. The efficacy of nested-PCR showed that it could re-amplify the direct-PCR product and detect 200 fg genomic DNA. PMID:24065525

  2. A GFP-based assay to quantify the impact of effectors on the ex planta development of the slowly growing barley pathogen Rhynchosporium commune.

    PubMed

    Kirsten, S; Siersleben, S; Knogge, W

    2011-01-01

    A growth assay was established for the barley pathogen Rhynchosporium commune with EGFP-tagged fungal mutants. This assay was used to study the effect of four antibiotics (hygromycin B, nourseothricin, kanamycin, phleomycin) and a herbicide (phosphinothricin) on fungal development. Fitting the growth curves to the modified Gompertz model allowed calculating growth parameters, such as lag periods of fungal colony formation and mycelial growth rates as well as EC(50) values. Except kanamycin all compounds were efficient inhibitors so that the corresponding resistance-conferring genes can be used as markers for selection of fungal transformation-based mutants. In addition the assay was used to quantify the inhibitory activity of a barley secondary metabolite, the indole alkaloid gramine. PMID:21498556

  3. Investigations of the in Planta Expression of Active Cellobiohydrolase I: Cooperative Research and Development Final Report, CRADA Number CRD-07-219

    SciTech Connect

    Himmel, M.

    2011-02-01

    It was the purpose of this project to determine if cellulases produced in transgenic plants could effectively be utilized in the production of ethanol and other feedstock chemicals from lignocellulosic substrates.

  4. Beetle and plant arrow poisons of the Ju|’hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae)

    PubMed Central

    Chaboo, Caroline S.; Biesele, Megan; Hitchcock, Robert K.; Weeks, Andrea

    2016-01-01

    Abstract The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San (“Bushmen”) arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called ‘click languages’ in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|’hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|’hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|’hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  5. Heterologous overexpression and biochemical characterization of the (galactophospho)lipase from Fusarium solani in Pichia pastoris that is expressed in planta.

    PubMed

    Jallouli, Raida; Ali, Madiha Bou; Charfeddine, Mariam; Gargouri-Bouzid, Radhia; Gargouri, Youssef; Bezzine, Sofiane

    2016-03-01

    High-level extracellular production of Fusarium solani (galactophospho)lipase, named FSL, was achieved using a Pichia pastoris X33 expression system. The (galactophospho) lipase encoding gene was cloned into pGAPZαA with the Saccharomyces cerevisiae α-factor signal sequence by two different ways. The two constructs consist of an additional sequence of a (His)6-tag of the vector fused to the N-terminus of this enzyme (tFSL) while the other expression vector was constructed without any additional sequence (rFSL). Compared to the native enzyme (nFSL) (18.75mg/L), a high level secretion of rFSL (310mg/L) and tFSL (240mg/L) was achieved providing an important improvement in enzyme production. Biochemical characterization showed that pure recombinant proteins (rFSL and tFSL) presented similar behaviour towards triglycerides, phospholipid and galactolipid. Like the nFSL, rFSL and tFSL are active at high concentration of bile salts (4mM) and calcium ions enhanced lipase activity. During plant infection, transcripts of this fungal lipase gene were detected 3, 7 and 10 days post infection. PMID:26675137

  6. Seed development and maturation in early spring-flowering Galanthus nivalis and Narcissus pseudonarcissus continues post-shedding with little evidence of maturation in planta

    PubMed Central

    Newton, Rosemary J.; Hay, Fiona R.; Ellis, Richard H.

    2013-01-01

    Background and Aims Seeds of the moist temperate woodland species Galanthus nivalis and Narcissus pseudonarcissus, dispersed during spring or early summer, germinated poorly in laboratory tests. Seed development and maturation were studied to better understand the progression from developmental to germinable mode in order to improve seed collection and germination practices in these and similar species. Methods Phenology, seed mass, moisture content and ability to germinate and tolerate desiccation were monitored during seed development until shedding. Embryo elongation within seeds was investigated during seed development and under several temperature regimes after shedding. Key Results Seeds were shed at high moisture content (>59 %) with little evidence that dry mass accumulation or embryo elongation were complete. Ability to germinate developed prior to the ability of some seeds to tolerate enforced desiccation. Germination was sporadic and slow. Embryo elongation occurred post-shedding in moist environments, most rapidly at 20 °C in G. nivalis and 15 °C in N. pseudonarcissus. The greatest germination also occurred in these regimes, 78 and 48 %, respectively, after 700 d. Conclusions Seeds of G. nivalis and N. pseudonarcissus were comparatively immature at shedding and substantial embryo elongation occurred post-shedding. Seeds showed limited desiccation tolerance at dispersal. PMID:23478943

  7. In Planta Recognition of a Double-Stranded RNA Synthesis Protein Complex by a Potexviral RNA Silencing Suppressor[C][W][OPEN

    PubMed Central

    Okano, Yukari; Senshu, Hiroko; Hashimoto, Masayoshi; Neriya, Yutaro; Netsu, Osamu; Minato, Nami; Yoshida, Tetsuya; Maejima, Kensaku; Oshima, Kenro; Komatsu, Ken; Yamaji, Yasuyuki; Namba, Shigetou

    2014-01-01

    RNA silencing plays an important antiviral role in plants and invertebrates. To counteract antiviral RNA silencing, most plant viruses have evolved viral suppressors of RNA silencing (VSRs). TRIPLE GENE BLOCK PROTEIN1 (TGBp1) of potexviruses is a well-characterized VSR, but the detailed mechanism by which it suppresses RNA silencing remains unclear. We demonstrate that transgenic expression of TGBp1 of plantago asiatica mosaic virus (PlAMV) induced developmental abnormalities in Arabidopsis thaliana similar to those observed in mutants of SUPPRESSOR OF GENE SILENCING3 (SGS3) and RNA-DEPENDENT RNA POLYMERASE6 (RDR6) required for the trans-acting small interfering RNA synthesis pathway. PlAMV-TGBp1 inhibits SGS3/RDR6-dependent double-stranded RNA synthesis in the trans-acting small interfering RNA pathway. TGBp1 interacts with SGS3 and RDR6 and coaggregates with SGS3/RDR6 bodies, which are normally dispersed in the cytoplasm. In addition, TGBp1 forms homooligomers, whose formation coincides with TGBp1 aggregation with SGS3/RDR6 bodies. These results reveal the detailed molecular function of TGBp1 as a VSR and shed new light on the SGS3/RDR6-dependent double-stranded RNA synthesis pathway as another general target of VSRs. PMID:24879427

  8. In planta processing and glycosylation of a nematode CLE effector and its interaction with a CLV2-like receptor to promote parasitism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ESR (CLE)-like proteins have been identified in several cyst nematodes including the potato cyst nematode (PCN); however, th...

  9. Regulon Studies and In Planta Role of the BraI/R Quorum-Sensing System in the Plant-Beneficial Burkholderia Cluster

    PubMed Central

    Coutinho, Bruna G.; Mitter, Birgit; Talbi, Chouhra; Sessitsch, Angela; Bedmar, Eulogio J.; Halliday, Nigel; James, Euan K.; Cámara, Miguel

    2013-01-01

    The genus Burkholderia is composed of functionally diverse species, and it can be divided into several clusters. One of these, designated the plant-beneficial-environmental (PBE) Burkholderia cluster, is formed by nonpathogenic species, which in most cases have been found to be associated with plants. It was previously established that members of the PBE group share an N-acyl-homoserine lactone (AHL) quorum-sensing (QS) system, designated BraI/R, that produces and responds to 3-oxo-C14-HSL (OC14-HSL). Moreover, some of them also possess a second AHL QS system, designated XenI2/R2, producing and responding to 3-hydroxy-C8-HSL (OHC8-HSL). In the present study, we performed liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis to determine which AHL molecules are produced by each QS system of this group of bacteria. The results showed that XenI2/R2 is mainly responsible for the production of OHC8-HSL and that the BraI/R system is involved in the production of several different AHLs. This analysis also revealed that Burkholderia phymatum STM815 produces greater amounts of AHLs than the other species tested. Further studies showed that the BraR protein of B. phymatum is more promiscuous than other BraR proteins, responding equally well to several different AHL molecules, even at low concentrations. Transcriptome studies with Burkholderia xenovorans LB400 and B. phymatum STM815 revealed that the BraI/R regulon is species specific, with exopolysaccharide production being the only common phenotype regulated by this system in the PBE cluster. In addition, BraI/R was shown not to be important for plant nodulation by B. phymatum strains or for endophytic colonization and growth promotion of maize by B. phytofirmans PsJN. PMID:23686262

  10. Analysis of two in planta expressed LysM effector homologs from the fungus Mycosphaerella graminicola reveals novel functional properties and varying contributions to virulence on wheat.

    PubMed

    Marshall, Rosalind; Kombrink, Anja; Motteram, Juliet; Loza-Reyes, Elisa; Lucas, John; Hammond-Kosack, Kim E; Thomma, Bart P H J; Rudd, Jason J

    2011-06-01

    Secreted effector proteins enable plant pathogenic fungi to manipulate host defenses for successful infection. Mycosphaerella graminicola causes Septoria tritici blotch disease of wheat (Triticum aestivum) leaves. Leaf infection involves a long (approximately 7 d) period of symptomless intercellular colonization prior to the appearance of necrotic disease lesions. Therefore, M. graminicola is considered as a hemibiotrophic (or necrotrophic) pathogen. Here, we describe the molecular and functional characterization of M. graminicola homologs of Ecp6 (for extracellular protein 6), the Lysin (LysM) domain-containing effector from the biotrophic tomato (Solanum lycopersicum) leaf mold fungus Cladosporium fulvum, which interferes with chitin-triggered immunity in plants. Three LysM effector homologs are present in the M. graminicola genome, referred to as Mg3LysM, Mg1LysM, and MgxLysM. Mg3LysM and Mg1LysM genes were strongly transcriptionally up-regulated specifically during symptomless leaf infection. Both proteins bind chitin; however, only Mg3LysM blocked the elicitation of chitin-induced plant defenses. In contrast to C. fulvum Ecp6, both Mg1LysM and Mg3LysM also protected fungal hyphae against plant-derived hydrolytic enzymes, and both genes show significantly more nucleotide polymorphism giving rise to nonsynonymous amino acid changes. While Mg1LysM deletion mutant strains of M. graminicola were fully pathogenic toward wheat leaves, Mg3LysM mutant strains were severely impaired in leaf colonization, did not trigger lesion formation, and were unable to undergo asexual sporulation. This virulence defect correlated with more rapid and pronounced expression of wheat defense genes during the symptomless phase of leaf colonization. These data highlight different functions for MgLysM effector homologs during plant infection, including novel activities that distinguish these proteins from C. fulvum Ecp6. PMID:21467214

  11. Taxonomic Treatment of Solanum Section Petota (Wild Potatoes) in Catálogo de Plantas Vasculares del Cono Sur (Argentina, Chile, Paraguay, Uruguay, y sur del Brasil)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solanum section Petota (Solanaceae), which includes the cultivated potato (Solanum tuberosum) and its wild relatives, contains over 150 wild species distributed from the southwestern U.S.A. (38°N) to central Argentina and adjacent Chile (41°S). This catalog includes all species from the Southern Con...

  12. CHARACTERIZATION, PHYLOGENY AND IN PLANTA EXPRESSION OF A PUTATIVE LIPASE GENE FROM MALAYSIAN PERIWINKLE YELLOWS (MPY) PHYTOPLASMA, A MEMBER OF SUBGROUP 16SRI-B

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent work revealed gene clusters occurring as multiple, sequence-variable mosaics in the genomes of several phytoplasmas (Jomantiene and Davis. 2006. FEMS Microbiol Letters 255:59-65.) Analysis of such a region, termed genomic sequence-variable mosaic (GSVM), in the genome of MPY phytoplasma reve...

  13. In planta imaging of Δ9-tetrahydrocannabinolic acid in Cannabis sativa L. with hyperspectral coherent anti-Stokes Raman scattering microscopy

    NASA Astrophysics Data System (ADS)

    Garbacik, Erik T.; Korai, Roza P.; Frater, Eric H.; Korterik, Jeroen P.; Otto, Cees; Offerhaus, Herman L.

    2013-04-01

    Nature has developed many pathways to produce medicinal products of extraordinary potency and specificity with significantly higher efficiencies than current synthetic methods can achieve. Identification of these mechanisms and their precise locations within plants could substantially increase the yield of a number of natural pharmaceutics. We report label-free imaging of Δ9-tetrahydrocannabinolic acid (THCa) in Cannabis sativa L. using coherent anti-Stokes Raman scattering microscopy. In line with previous observations we find high concentrations of THCa in pistillate flowering bodies and relatively low amounts within flowering bracts. Surprisingly, we find differences in the local morphologies of the THCa-containing bodies: organelles within bracts are large, diffuse, and spheroidal, whereas in pistillate flowers they are generally compact, dense, and have heterogeneous structures. We have also identified two distinct vibrational signatures associated with THCa, both in pure crystalline form and within Cannabis plants; at present the exact natures of these spectra remain an open question.

  14. Proteins with High Turnover Rate in Barley Leaves Estimated by Proteome Analysis Combined with in Planta Isotope Labeling1[W][OPEN

    PubMed Central

    Nelson, Clark J.; Alexova, Ralitza; Jacoby, Richard P.; Millar, A. Harvey

    2014-01-01

    Protein turnover is a key component in cellular homeostasis; however, there is little quantitative information on degradation kinetics for individual plant proteins. We have used 15N labeling of barley (Hordeum vulgare) plants and gas chromatography-mass spectrometry analysis of free amino acids and liquid chromatography-mass spectrometry analysis of proteins to track the enrichment of 15N into the amino acid pools in barley leaves and then into tryptic peptides derived from newly synthesized proteins. Using information on the rate of growth of barley leaves combined with the rate of degradation of 14N-labeled proteins, we calculate the turnover rates of 508 different proteins in barley and show that they vary by more than 100-fold. There was approximately a 9-h lag from label application until 15N incorporation could be reliably quantified in extracted peptides. Using this information and assuming constant translation rates for proteins during the time course, we were able to quantify degradation rates for several proteins that exhibit half-lives on the order of hours. Our workflow, involving a stringent series of mass spectrometry filtering steps, demonstrates that 15N labeling can be used for large-scale liquid chromatography-mass spectrometry studies of protein turnover in plants. We identify a series of abundant proteins in photosynthesis, photorespiration, and specific subunits of chlorophyll biosynthesis that turn over significantly more rapidly than the average protein involved in these processes. We also highlight a series of proteins that turn over as rapidly as the well-known D1 subunit of photosystem II. While these proteins need further verification for rapid degradation in vivo, they cluster in chlorophyll and thiamine biosynthesis. PMID:25082890

  15. Vascular Streak Dieback of cacao in Southeast Asia detection and Melanesia: in planta detection of the pathogen and a new taxonomy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular Streak Dieback (VSD) disease of cacao (Theobroma cacao) in Southeast Asia and Melanesia is caused by a basidiomycete (Ceratobasidiales) fungus described in a monotypic genus as Oncobasidium theobromae (syn. =Thanatephorus theobromae). The symptoms of the disease include green-spotted chloro...

  16. Development and Use of a Reverse Transcription-PCR Assay To Study Expression of Tri5 by Fusarium Species In Vitro and In Planta

    PubMed Central

    Doohan, F. M.; Weston, G.; Rezanoor, H. N.; Parry, D. W.; Nicholson, P.

    1999-01-01

    The Tri5 gene encodes trichodiene synthase, which catalyzes the first reaction in the trichothecene biosynthetic pathway. In vitro, a direct relationship was observed between Tri5 expression and the increase in deoxynivalenol production over time. We developed a reverse transcription (RT)-PCR assay to quantify Tri5 gene expression in trichothecene-producing strains of Fusarium species. We observed an increase in Tri5 expression following treatment of Fusarium culmorum with fungicides, and we also observed an inverse relationship between Tri5 expression and biomass, as measured by β-d-glucuronidase activity, during colonization of wheat (cv. Avalon) seedlings by F. culmorum. RT-PCR analysis also showed that for ears of wheat cv. Avalon inoculated with F. culmorum, there were different levels of Tri5 expression in grain and chaff at later growth stages. We used the Tri5-specific primers to develop a PCR assay to detect trichothecene-producing Fusarium species in infected plant material. PMID:10473385

  17. In Planta Variation of Volatile Biosynthesis: An Alternative Biosynthetic Route to the Formation of the Pathogen-Induced Volatile Homoterpene DMNT via Triterpene Degradation in Arabidopsis Roots

    PubMed Central

    Sohrabi, Reza; Huh, Jung-Hyun; Badieyan, Somayesadat; Rakotondraibe, Liva Harinantenaina; Kliebenstein, Daniel J.; Sobrado, Pablo; Tholl, Dorothea

    2015-01-01

    Plant-derived volatile compounds such as terpenes exhibit substantial structural variation and serve multiple ecological functions. Despite their structural diversity, volatile terpenes are generally produced from a small number of core 5- to 20-carbon intermediates. Here, we present unexpected plasticity in volatile terpene biosynthesis by showing that irregular homo/norterpenes can arise from different biosynthetic routes in a tissue specific manner. While Arabidopsis thaliana and other angiosperms are known to produce the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) or its C16-analog (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene by the breakdown of sesquiterpene and diterpene tertiary alcohols in aboveground tissues, we demonstrate that Arabidopsis roots biosynthesize DMNT by the degradation of the C30 triterpene diol, arabidiol. The reaction is catalyzed by the Brassicaceae-specific cytochrome P450 monooxygenase CYP705A1 and is transiently induced in a jasmonate-dependent manner by infection with the root-rot pathogen Pythium irregulare. CYP705A1 clusters with the arabidiol synthase gene ABDS, and both genes are coexpressed constitutively in the root stele and meristematic tissue. We further provide in vitro and in vivo evidence for the role of the DMNT biosynthetic pathway in resistance against P. irregulare. Our results show biosynthetic plasticity in DMNT biosynthesis in land plants via the assembly of triterpene gene clusters and present biochemical and genetic evidence for volatile compound formation via triterpene degradation in plants. PMID:25724638

  18. Beetle and plant arrow poisons of the Ju|'hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae).

    PubMed

    Chaboo, Caroline S; Biesele, Megan; Hitchcock, Robert K; Weeks, Andrea

    2016-01-01

    The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San ("Bushmen") arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called 'click languages' in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|'hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|'hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|'hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  19. The Pratylenchus penetrans Transcriptome as a Source for the Development of Alternative Control Strategies: Mining for Putative Genes Involved in Parasitism and Evaluation of in planta RNAi.

    PubMed

    Vieira, Paulo; Eves-van den Akker, Sebastian; Verma, Ruchi; Wantoch, Sarah; Eisenback, Jonathan D; Kamo, Kathryn

    2015-01-01

    The root lesion nematode Pratylenchus penetrans is considered one of the most economically important species within the genus. Host range studies have shown that nearly 400 plant species can be parasitized by this species. To obtain insight into the transcriptome of this migratory plant-parasitic nematode, we used Illumina mRNA sequencing analysis of a mixed population, as well as nematode reads detected in infected soybean roots 3 and 7 days after nematode infection. Over 140 million paired end reads were obtained for this species, and de novo assembly resulted in a total of 23,715 transcripts. Homology searches showed significant hit matches to 58% of the total number of transcripts using different protein and EST databases. In general, the transcriptome of P. penetrans follows common features reported for other root lesion nematode species. We also explored the efficacy of RNAi, delivered from the host, as a strategy to control P. penetrans, by targeted knock-down of selected nematode genes. Different comparisons were performed to identify putative nematode genes with a role in parasitism, resulting in the identification of transcripts with similarities to other nematode parasitism genes. Focusing on the predicted nematode secreted proteins found in this transcriptome, we observed specific members to be up-regulated at the early time points of infection. In the present study, we observed an enrichment of predicted secreted proteins along the early time points of parasitism by this species, with a significant number being pioneer candidate genes. A representative set of genes examined using RT-PCR confirms their expression during the host infection. The expression patterns of the different candidate genes raise the possibility that they might be involved in critical steps of P. penetrans parasitism. This analysis sheds light on the transcriptional changes that accompany plant infection by P. penetrans, and will aid in identifying potential gene targets for selection and use to design effective control strategies against root lesion nematodes. PMID:26658731

  20. INCIDENCE, AGRESSIVENESS AND IN PLANTA INTERACTIONS OF BOTRYTIS CINEREA ANDOTHER FILAMENTOUS FUNGI QUIESCENT IN GRAPE BERRIES AND DORMANT BUDS IN CENTRAL WASHINGTON STATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recovery of quiescent filamentous fungi from non-symptomatic grape berries and dormant buds demonstrated dominance of Alternaria, Aureobasidium, Cladosporium, Ulocladium and other dematiaceous hyphomycetes. Up to 78% of berries contained fungi prior to harvest. Botrytis cinerea was recovered from 0...

  1. Monomeric IgA can be produced in planta as efficient as IgG, yet receives different N-glycans.

    PubMed

    Westerhof, Lotte B; Wilbers, Ruud H P; van Raaij, Debbie R; Nguyen, Dieu-Linh; Goverse, Aska; Henquet, Maurice G L; Hokke, Cornelis H; Bosch, Dirk; Bakker, Jaap; Schots, Arjen

    2014-12-01

    The unique features of IgA, such as the ability to recruit neutrophils and suppress the inflammatory responses mediated by IgG and IgE, make it a promising antibody isotype for several therapeutic applications. However, in contrast to IgG, reports on plant production of IgA are scarce. We produced IgA1κ and IgG1κ versions of three therapeutic antibodies directed against pro-inflammatory cytokines in Nicotiana benthamiana: Infliximab and Adalimumab, directed against TNF-α, and Ustekinumab, directed against the interleukin-12p40 subunit. We evaluated antibody yield, quality and N-glycosylation. All six antibodies had comparable levels of expression between 3.5 and 9% of total soluble protein content and were shown to have neutralizing activity in a cell-based assay. However, IgA1κ-based Adalimumab and Ustekinumab were poorly secreted compared to their IgG counterparts. Infliximab was poorly secreted regardless of isotype backbone. This corresponded with the observation that both IgA1κ- and IgG1κ-based Infliximab were enriched in oligomannose-type N-glycan structures. For IgG1κ-based Ustekinumab and Adalimumab, the major N-glycan type was the typical plant complex N-glycan, biantennary with terminal N-acetylglucosamine, β1,2-xylose and core α1,3-fucose. In contrast, the major N-glycan on the IgA-based antibodies was xylosylated, but lacked core α1,3-fucose and one terminal N-acetylglucosamine. This type of N-glycan occurs usually in marginal percentages in plants and was never shown to be the main fraction of a plant-produced recombinant protein. Our data demonstrate that the antibody isotype may have a profound influence on the type of N-glycan an antibody receives. PMID:25196296

  2. Velocidades radiales en Collinder 121

    NASA Astrophysics Data System (ADS)

    Arnal, M.; Morrell, N.

    Se han llevado a cabo observaciones espectroscópicas de unas treinta estrellas que son posibles miembros del cúmulo abierto Collinder 121. Las mismas fueron realizadas con el telescopio de 2.15m del Complejo Astronómico El Leoncito (CASLEO). El análisis de las velocidades radiales derivadas del material obtenido, confirma la realidad de Collinder 121, al menos desde el punto de vista cinemático. La velocidad radial baricentral (LSR) del cúmulo es de +17 ± 3 km.s-1. Esta velocidad coincide, dentro de los errores, con la velocidad radial (LSR) de la nebulosa anillo S308, la cual es de ~20 ± 10 km.s-1. Como S308 se encuentra físicamente asociada a la estrella Wolf-Rayet HD~50896, es muy probable que esta última sea un miembro de Collinder 121. Desde un punto de vista cinemático, la supergigante roja HD~50877 (K3Iab) también pertenecería a Collinder 121. Basándonos en la pertenencia de HD~50896 a Collinder 121, y en la interacción encontrada entre el viento de esta estrella y el medio interestelar circundante a la misma, se estima para este cúmulo una distancia del orden de 1 kpc.

  3. L'Harmonisation des langues maliennes: entre l'Integration nationale et régionale

    NASA Astrophysics Data System (ADS)

    Ouane, Adama

    1991-03-01

    The standardization of Malian languages, which began in the period after independence, has been an educational reform guided more by linguists than by any institutional framework laid down by the political authorities of the country. This situation has permitted the technical application of a scientific strategy, but it has not led to widespread and general acceptance of the formulas which have been worked out. The consequent opposition between technical and political considerations, which have admittedly not always been in conflict, has been complicated by a set of additional factors which have made it difficult to reconcile internal (national) harmonization, dictated by local tendencies and balances between languages, and the need to respect the (regional) ecolinguistics of the country, whose linguistic and sociocultural divisions frequently extend well into other countries of the sub-region. This conflict is illustrated by the example of Malian languages with a wide regional distribution — Bamanan (Bambara) and Fulfulde (Fulani) — and by that of languages with a narrower distribution such as Bomu and Syenara-Mamara. The standardization of orthography and the creation of terminology in the MAPE (Mandingo-Peul) Project are the manifestation of a general acceptance of regionalism, while the choice of central, standard languages has often been made without regard for regional factors.

  4. La formation a Bukavu au Zaire: une course entre l'education et la catastrophe

    NASA Astrophysics Data System (ADS)

    Balegamire, Bazilashe Juvénal

    1996-11-01

    A description of the socio-educational situation in Bukavu since the colonial era clearly shows why the population has sought means of overcoming the gradual abandonment by the Zairean State of its responsibilities, which has been aggravated by the large-scale influx into Kivu, in Eastern Zaire, of refugees from Rwanda and Burundi and of Zaireans who has been living in those countries for some years. These means are principally trade occupations, small-time selling, short-term vocational training and higher and university education at private institutions which are financed locally and/or by funds from the North. A new approach has been deveoped, that of training the trainers working for non-governmental development organisations. Trainers of trainers have been recruited locally among the many graduates of the Higher Institutes of Education and Rural Development, which have been affected by unemployment and the miserable salaries which the State offers to its employees. The trainers of trainers could be trained by the Higher Institute of Rural Development, making the largest possible use of local skills. However, such training should be one of a set of reforms of the Zairean education system. All of this only makes sense if Zaire and its neighbours urgently defuse present socio-political tensions so that all of our populations can peacefully and resolutely engage in the healthy transformation of our societies.

  5. La Communicacion entre los Centros de Investigacion en Educacion (Communication among Educational Research Centers).

    ERIC Educational Resources Information Center

    Schiefelbein, Ernesto

    1972-01-01

    In Latin America there is a lack of communication concerning educational research. This lack has been underlined in many regional meetings, but no action has been taken. Possible steps that would lead to improvement include circulation of research summaries, both for completed and current works, efforts by research centers to organize meetings,…

  6. L' upwelling de la côte atlantique du Maroc entre 1994 et 1998

    NASA Astrophysics Data System (ADS)

    Makaoui, Ahmed; Orbi, Abdelattif; Hilmi, Karim; Zizah, Soukaina; Larissi, Jamila; Talbi, Mohammed

    2005-12-01

    The pelagic ecosystem of the Moroccan Atlantic coast is influenced by the spatiotemporal variability of upwelling. The changes in the physicochemical and biological parameters as well as their interrelationship and regrouping by the principal components analysis allowed us to subdivide the Atlantic coast in four active areas: two areas located at the north of Cape Juby (28°N), characterised by a summery activity and two areas located at the south, active permanently, with a variable intensity. To cite this article: A. Makaoui et al., C. R. Geoscience 337 (2005).

  7. GPS, punto de contacto entre la Astronomía y otras disciplinas

    NASA Astrophysics Data System (ADS)

    Perdomo, R.

    En los primeros años de la pasada década, un grupo de Astrónomos de La Plata iniciaron trabajos de investigación en Geodesia Satelital. En esta presentación se propone repasar sus principales logros y situarlos en el contexto del desarrollo de la disciplina a nivel mundial. Por entonces las aplicaciones prácticas de la disciplina eran indirectas y solo evidentes para los especialistas. Los errores del Posicionamiento Satelital eran de varios metros y en posicionamiento relativo, del orden de medio metro. Estos resultados se lograban al cabo de varios días de medición continuada. En los años siguientes, el sistema GPS alcanzó su nivel operacional y produjo una revolución tanto en lo relacionado con los tiempos de medición como con las precisiones. El grupo de La Plata se desarrolló simultáneamente con GPS, lo que posibilitó su participación actual en diversos temas vigentes: aplicaciones de alta precisión para la materialización de sistemas terrestres de referencia, monitoreo de movimientos de la corteza, contribución con servicios internacionales para la determinación de movimientos tectónicos globales y regionales, monitoreo de la ionósfera a partir de la propagación de las señales, determinación de la ondulación del geoide a escala local, etc. También se generaron muchas aplicaciones prácticas algunas en tiempo real: navegación, apoyo a imágenes aéreas o satelitales, aplicaciones a la agricultura, catastro y ordenamiento territorial, apoyo a relevamientos geofísicos, etc.

  8. Entre Reproduction et Mobilisation: les Rapports de Genre EN Formation Continue EN France et AU Canada

    NASA Astrophysics Data System (ADS)

    Fourner, Christine; Béret, Pierre; Doray, Pierre; Bélanger, Paul

    2009-01-01

    REPRODUCTION OR MOBILISATION? GENDER PROPORTIONS IN CONTINUING EDUCATION IN FRANCE AND CANADA - Initial education provisions for women have evolved greatly over the past 40 years. But what about their situation within adult education and training? This article, comparing Canada and France, shows that, while it is well known that more women than men participate in adult education, their greater presence in professional training courses is a new development. The analysis highlights certain particular findings, such as the growing demand for continuing education in Canada and the increased rate of participation by full-time employees in France. In both countries, a number of social factors continue to influence women's participation.

  9. Let's Talk About Water: Film Screenings as an Entrée to Water Science

    NASA Astrophysics Data System (ADS)

    Hooper, R. P.; Lilienfeld, L.; Arrigo, J.

    2011-12-01

    "Let's Talk about Water" is a film symposium designed to bring together experts and the public to talk about the complex water issues facing society. The format of the event is quite simple: a panel of experts and the audience view a water documentary (such as "FLOW", "Liquid Assets", or "Gasland") together and there is an extended moderated discussion period following the film between the panel and the audience. Properly handled, this simple format can be very effective. A film creates a context of subject and language for the discussion--it gets the audience and the panel on the same page. The moderators must actively manage the discussion, both challenging the panelists with follow up questions, asking questions to simplify the language the expert is using, and passing a question among panelists to bring out different points of view. The panelists are provided with the film in advance to view and, most importantly, meet the day before the event to discuss the film. This makes for a much more convivial discussion at the event. We have found that these discussions can easily be sustained for 90 to 120 minutes with active audience participation. This format has been applied at college campuses with a target audience of lower-level undergraduates. Student clubs are engaged to help with publicity before the event and to assist with registration and ushering during the event. Appropriate classes offer extra credit for student attendance to ensure a strong turnout. A Hollywood film ("Chinatown" in southern California, "A Civil Action" in Boston) is shown on campus during the week preceding the event to help advertise the event. The event itself is typically held on a Saturday with a morning screening of the film. The audience is provided with index cards and pencils to write down questions they have about the film. A lunch is provided during which the questions are organized and used to initiate different discussion themes. The discussion begins with points raised by the movie (are these issues real? Do they apply here? What are the scientific, engineering, and policy solutions to these problems?) and then segues into a discussion about career opportunities in the water sector. Our past events at UC Irvine and at UMass Boston have been successful in attracting large audiences and have been viewed positively by attendees.

  10. Vinculación entre varios cúmulos estelares y estructuras del medio interestelar

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Baume, G. L.; Panei, J. A.; Suad, L. A.; Testori, J. C.; Borissova, J.; Kurtev, R.; Chené, A. N.; Ramirez Alegría, S.

    2015-08-01

    We study the embedded clusters DBS77, 78, 102, 160, and 161 located in the Galactic plane in the fourth quadrant of the Milky Way and the surrounding interstellar medium (ISM). We analyzed UBVIc photometry (SOAR) and infrared spectroscopy (NTT, ESO). We complemented these data with JHK (VVV2MASS), HI 21 cm bands (SGPS), 1.4 GHz (ATCA), and 4.85 GHz (PMN). We did multiband analysis and spectral classification of the brightest stars in each area. We also identified the ISM structures possibly related to the clusters. Finally, we obtained the main parameters of the studied clusters, the structures of the ISM and the link between them.

  11. Entre Nous: A Tutorial Approach to the Teaching of Business French.

    ERIC Educational Resources Information Center

    Chaisson, Arthur P.

    Suffolk University (Massachusetts) has developed a degree program in international marketing in French and Spanish that links curricula in the economics department and the department of humanities and modern languages. Language tutorials are mandatory for students in the international economics major. The tutorials are taught by native French- and…

  12. New York: Les ecoles entre SURR et STAR (New York: Schools between SURR and STAR).

    ERIC Educational Resources Information Center

    Ueberschlag, Roger

    1994-01-01

    Three problems of New York City (New York) schools--overpopulation, low academic standards, violence--are examined, and an effort led by parent and teacher organizations to improve conditions is described. Threatened closings (schools under registration review, SURR) and a program of violence reduction (Straight Talk about Risks, STAR) are noted.

  13. New York: Les ecoles entre SURR et STAR (New York: Schools between SURR and STAR).

    ERIC Educational Resources Information Center

    Ueberschlag, Roger

    1994-01-01

    Three problems of New York City (New York) schools--overpopulation, low academic standards, violence--are examined, and an effort led by parent and teacher organizations to improve conditions is described. Threatened closings (schools under registration review, SURR) and a program of violence reduction (Straight Talk about Risks, STAR) are noted.…

  14. Dominicanas entre La Gran Manzana y Quisqueya: Family, Schooling, and Language Learning in a Transnational Context

    ERIC Educational Resources Information Center

    Rodriguez, Tracy

    2009-01-01

    Drawing from a one-year qualitative research study, this article explores the transnational lives and experiences of three young women and their little sisters in New York with close ties to the Dominican Republic. Using ethnographic research methods--life history interviews, focus groups, participant observation, and document analysis, I examine…

  15. "Entre Familia": Immigrant Parents' Strategies for Involvement in Children's Schooling

    ERIC Educational Resources Information Center

    Poza, Luis; Brooks, Maneka Deanna; Valdés, Guadalupe

    2014-01-01

    Teachers and administrators in schools with large, working-class Latino populations often complain of parents' indifference or lack of involvement in children's schooling because of their low visibility at school events and relatively little face-to-face communication with teachers and school administration. In a series of…

  16. Apoyo a Estudios Geodinamicos con GPS en Guatemala

    NASA Astrophysics Data System (ADS)

    Robles, V. R.

    2013-05-01

    El Instituto Geografico Nacional de Guatemala implemento 17 estaciones GNSS en el año 2009, como un proyecto de credito mixto de donacion de equipamiento del Gobierno de Suiza, el cual, este equipamiento de estaciones CORS GNSS es un sistema de recepción y transmisión de datos crudos GPS RInex que utiliza la tecnologia Spider Web de Leica, asi mismo este sistema esta sirviendo para el espablecimiento de un marco geodesico nacional de coordenadas geodesicas oficiales, el cual se calculan u obtienen las velocidades en tiempos temporales programados de las 17 Estaciones CORS. La infraestructura del marco geodesico de Guatemala esta sirviendo de base para las aplicaciones de estudios geodinamicos como el monitoreo de del desplazamiento de las placas tectonicas por medio de un estudio que se inicio en el año de 1999, llamado medicion con GPS el sistema de Fallas de los rios Polochic Motagua de Guatemala, tambien para un estudio que se implemento para deformación de corteza terrestre local en un Volcan Activo de Guatemala llamado Pacaya. Para el estudio de medicion con GPS en el sistema de falla de los Rios del polochic Motagua se implementaron 16 puntos para medir con GPS de dos frecuencias en el año de 1999, el cual, tres puntos son estaciones geodesicas CORS IGS llamados GUAT, ELEN y HUEH, despues en el año de 2003 se hizo otra medicion en un total de 20 puntos, que permitió calcular las velocidades de desplazamieinto de los puntos en mención, usando como referencia el modelo NUVEL 1A de DeMets de la placa de Norteamerica. Este estudio fue en cooperación internacional por la universidad de Nice de Francia y el IGNde Francia. Para el estudio del monitoreo con GPS del volcan activo de Guatemala, se implementaron cuatro puntos al rededor del volcan, el cual, se realizan cuatro mediciones al año, que permiten determinar axialmente la distancias entre los puntos, y rebisar estadisticamente cual es el comportamiento de las distancias en funcion del tiempo, si existen diferencias graduales crecientes o decrecientes, que nos da un indicativo del desplazamiento de la corteza terrestre al rededor del volcan.

  17. Estudio comparativo de cúmulos abiertos ricos en estrellas masivas

    NASA Astrophysics Data System (ADS)

    Baume, G.; Feinstein, A.; Vázquez, R. A.

    Los cúmulos abiertos muy jóvenes proveen valiosa información sobre las teorías de evolución estelar. No obstante, no se conoce mucho sobre los miembros mas débiles de estos objetos. Se llevaron a cabo entonces, estudios detallados (fotometría CCD-UBVI y polarimetría) en los cúmulos abiertos: Tr 14, Cr 272, Stok 16, NGC 6231, NGC 3293 y HM 1. Se realizó entonces un análisis comparativo entre ellos y con los objetos Pismis 20 (Vázquez et al. 1995) y NGC 5606 (Vázquez et al. 1994). En particular, se analizó la secuencia principal inferior de los distintos cúmulos, se estudió la extinción interestelar y las propiedades del polvo, se determinaron las correspondientes IMF, y se estudió la forma en que se distribuyen las estrellas menos masivas en relación con las más masivas. Como conclusiones del trabajo se puede decir que se han redeterminado con mayor precisión las distancias y las edades de los objetos bajo estudio, se han hallado varias estrellas con alta probabilidad de estar en fase de contracción y se ha notado una dispersión de edad entre las estrellas más brillantes y las menos brillantes (confirmando la idea de que la formación estelar no es simultánea ni independiente de la masa). Además, se han encontrado que las pendientes de las IMFs de estos objetos son más planas que la de las estrellas de campo y las de cúmulos más evolucionados, siendo comparable con las halladas en objetos jóvenes de la Nube Mayor de Magallanes (Will et al. 1996).

  18. Movimientos peculiares de galaxias en el Universo cercano

    NASA Astrophysics Data System (ADS)

    Alonso, M. V.

    Se presenta un resumen de los resultados más importantes obtenidos en los últimos años sobre movimientos peculiares en el Universo Cercano. En el escenario de inestabilidad gravitacional, el campo de velocidades peculiares es una herramienta muy útil para estimar las fluctuaciones en la distribución de masa que generan los movimientos observados. Esta aproximación puede, además, ser utilizada para poner restricciones al espectro de potencia de la masa, a la relación entre las distribuciones de galaxias y de materia y al valor del parámetro de densidad cosmológico, Ω, a grandes escalas. Son además presentados una reconstrucción preliminar de los campos de densidad de masa y velocidades peculiares en el universo cercano usando nuevas medidas de distancias obtenidas con la relación Dn - σ, para una muestra de galaxias elípticas y lenticulares. Dos subestructuras prominentes son encontradas en la región del Gran Atractor, que corresponden a los complejos de Centaurus y Pavo--Indus. Estos últimos, junto a los complejos de Perseus--Piscis y Cetus parecen ser importantes estructuras que determinan el flujo global. El patrón obtenido a través de una muestra de galaxias elípticas muestra variaciones con respecto al obtenido por galaxias espirales. Estos nuevos resultados muestran una coherencia menor en el flujo global, cuando son comparados con resultados obtenidos anteriormente.

  19. Relación entre distribuciones de colisiones de baja energía y trayectorias de escape

    NASA Astrophysics Data System (ADS)

    Zoppetti, F. A.; Leiva, A. M.; Briozzo, C. B.

    In the restricted three-body problem; the impact distributions on the secondary mass originated by low-energy trajectories exhibit peculiar properties concerning the positions and directions of the impacts. In particular; for low energies there are regions on the surface of the secondary mass where no collisions happen. On the other hand; similar surface distributions can be obtained when only considering those test particles whose low-energy trajectories satisfy the escape condition. In this work; taking into account the Earth-Moon problem; we analyze the relations between these two distributions and discuss their possible applications. FULL TEXT IN SPANISH

  20. Astronomie in Stein. Archäologen und Astronomen enträtseln alte Bauwerke und Kultstätten.

    NASA Astrophysics Data System (ADS)

    Drößler, R.

    Contents: 1. Archäoastronomie - eine moderne Wissenschaft. 2. Der Blick zur Sonne. 3. Streit um die Geometrie der Steinzeit. 4. Erdwerke, Henges und steinzeitlicher Sonnenkalender. 5. Fakten und Spekulationen. 6. Von Scharrbildern und Medizinrädern.

  1. Interactivite, relations entre interlocuteurs et constitution d'unites conversationnelles (Interaction Processes, Participants' Relationships and Definition of Conversation Units).

    ERIC Educational Resources Information Center

    Zenone, Anna

    1981-01-01

    Analyzes a type of conversational exchange where the participants focus on a given subject or theme contributing personal views to the discussion. Characterizes the relationship among the participants as a "cooperative conflict," examining the internal structure of speech acts and their illocutory functions, particularly the initiatory and…

  2. Neuropatía persistente aumenta el riesgo de caídas entre supervivientes de cáncer

    Cancer.gov

    Muchas mujeres supervivientes de cáncer tienen problemas de movilidad y de otras funciones físicas como resultado de la neuropatía periférica persistente causada por el tratamiento de quimioterapia, según un estudio nuevo.

  3. Metonymie dans la presse ecrite: entre discours et langue (Metonymies in the Press: Between Discourse and Language).

    ERIC Educational Resources Information Center

    Lecolle, Michelle

    2001-01-01

    This paper describes certain metonymies that are often employed in the daily French press. In such metonymies, a human being or a set of individuals are referred to by means of the name of an institutional location (i.e., a capital city, a ministry in a western country, the name of a country). These metonymic patterns do not seem to be used by…

  4. Entre el Renacimiento y el Nuevo Mundo: Vida y obras de Hernan Perez de Oliva (1494?-1531)

    ERIC Educational Resources Information Center

    Pellus Perez, Elena

    2012-01-01

    Hernan Perez de Oliva (1494?-1531) was a learned Spanish humanist who wrote his major works in the decades following the discovery of America. By articulating events of his career and literary life, my goal is to comprehend his contributions to the early literary production regarding the newly-found Americas. The thesis consists of three parts.

  5. Detection of PhIP in grilled chicken entrées at popular chain restaurants throughout California.

    PubMed

    Sullivan, Kristie M; Erickson, Michael A; Sandusky, Chad B; Barnard, Neal D

    2008-01-01

    Heterocyclic amines (HCAs), compounds formed when meat is cooked at high temperatures particularly through pan frying, grilling, or barbequing, pose a potential carcinogenic risk to the public. It is unclear whether there is any level at which consumption of HCAs can be considered safe. Efforts to measure these compounds mainly include cooking studies under laboratory conditions and some measurement of home-cooked foods, but analysis of commercially cooked foods has been minimal. Attempts to estimate exposure of the public to these compounds must take into consideration dining outside the home, which could result in significant exposure for some individuals. We surveyed at least 9 locations each of 7 popular chain restaurants (McDonald's, Burger King, Chick-fil-A, Chili's, TGI Friday's, Outback Steakhouse, and Applebee's) in California, collecting one or two entrees from each location. Entrees were analyzed for 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) using high-performance liquid chromatography tandem mass spectrometry. All 100 samples contained PhIP. Concentrations were variable within and between entrees and ranged from 0.08 to 43.2 ng/g. When factoring in the weight of the entrees, absolute levels of PhIP reached over 1,000 ng for some entrees. Potential strategies for reducing exposure include the avoidance of meats cooked using methods that are known to form PhIP. PMID:18791922

  6. Detection of PhIP in grilled chicken entrées at popular chain restaurants throughout California.

    TOXLINE Toxicology Bibliographic Information

    Sullivan KM; Erickson MA; Sandusky CB; Barnard ND

    2008-01-01

    Heterocyclic amines (HCAs), compounds formed when meat is cooked at high temperatures particularly through pan frying, grilling, or barbequing, pose a potential carcinogenic risk to the public. It is unclear whether there is any level at which consumption of HCAs can be considered safe. Efforts to measure these compounds mainly include cooking studies under laboratory conditions and some measurement of home-cooked foods, but analysis of commercially cooked foods has been minimal. Attempts to estimate exposure of the public to these compounds must take into consideration dining outside the home, which could result in significant exposure for some individuals. We surveyed at least 9 locations each of 7 popular chain restaurants (McDonald's, Burger King, Chick-fil-A, Chili's, TGI Friday's, Outback Steakhouse, and Applebee's) in California, collecting one or two entrees from each location. Entrees were analyzed for 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) using high-performance liquid chromatography tandem mass spectrometry. All 100 samples contained PhIP. Concentrations were variable within and between entrees and ranged from 0.08 to 43.2 ng/g. When factoring in the weight of the entrees, absolute levels of PhIP reached over 1,000 ng for some entrees. Potential strategies for reducing exposure include the avoidance of meats cooked using methods that are known to form PhIP.

  7. Alternancia entre el estado de emisión de Rayos-X y Pulsar en Sistemas Binarios Interactuantes

    NASA Astrophysics Data System (ADS)

    De Vito, M. A.; Benvenuto, O. G.; Horvath, J. E.

    2015-08-01

    Redbacks belong to the family of binary systems in which one of the components is a pulsar. Recent observations show redbacks that have switched their state from pulsar - low mass companion (where the accretion of material over the pulsar has ceased) to low mass X-ray binary system (where emission is produced by the mass accretion on the pulsar), or inversely. The irradiation effect included in our models leads to cyclic mass transfer episodes, which allow close binary systems to switch between one state to other. We apply our results to the case of PSR J1723-2837, and discuss the need to include new ingredients in our code of binary evolution to describe the observed state transitions.

  8. Entre el Renacimiento y el Nuevo Mundo: Vida y obras de Hernan Perez de Oliva (1494?-1531)

    ERIC Educational Resources Information Center

    Pellus Perez, Elena

    2012-01-01

    Hernan Perez de Oliva (1494?-1531) was a learned Spanish humanist who wrote his major works in the decades following the discovery of America. By articulating events of his career and literary life, my goal is to comprehend his contributions to the early literary production regarding the newly-found Americas. The thesis consists of three parts.…

  9. In planta Identification of Putative Pathogenicity Factors from the Chickpea Pathogen Ascochyta rabiei by De novo Transcriptome Sequencing Using RNA-Seq and Massive Analysis of cDNA Ends

    PubMed Central

    Fondevilla, Sara; Krezdorn, Nicolas; Rotter, Björn; Kahl, Guenter; Winter, Peter

    2015-01-01

    The most important foliar diseases in legumes worldwide are ascochyta blights. Up to now, in the Ascochyta-legume pathosystem most studies focused on the identification of resistance genes in the host, while very little is known about the pathogenicity factors of the fungal pathogen. Moreover, available data were often obtained from fungi growing under artificial conditions. Therefore, in this study we aimed at the identification of the pathogenicity factors of Ascochyta rabiei, causing ascochyta blight in chickpea. To identify potential fungal pathogenicity factors, we employed RNA-seq and Massive Analysis of cDNA Ends (MACE) to produce comprehensive expression profiles of A. rabiei genes isolated either from the fungus growing in absence of its host or from fungi infecting chickpea leaves. We further provide a comprehensive de novo assembly of the A. rabiei transcriptome comprising 22,725 contigs with an average length of 1178 bp. Since pathogenicity factors are usually secreted, we predicted the A. rabiei secretome, yielding 550 putatively secreted proteins. MACE identified 596 transcripts that were up-regulated during infection. An analysis of these genes identified a collection of candidate pathogenicity factors and unraveled the pathogen's strategy for infecting its host. PMID:26648917

  10. Arabidopsis SHR and SCR transcription factors and AUX1 auxin influx carrier control the switch between adventitious rooting and xylogenesis in planta and in in vitro cultured thin cell layers

    PubMed Central

    Della Rovere, F.; Fattorini, L.; D’Angeli, S.; Veloccia, A.; Del Duca, S.; Cai, G.; Falasca, G.; Altamura, M. M.

    2015-01-01

    Background and Aims Adventitious roots (ARs) are essential for vegetative propagation. The Arabidopsis thaliana transcription factors SHORT ROOT (SHR) and SCARECROW (SCR) affect primary/lateral root development, but their involvement in AR formation is uncertain. LAX3 and AUX1 auxin influx carriers contribute to primary/lateral root development. LAX3 expression is regulated by SHR, and LAX3 contributes to AR tip auxin maximum. In contrast, AUX1 involvement in AR development is unknown. Xylogenesis is induced by auxin plus cytokinin as is AR formation, but the genes involved are largely unknown. Stem thin cell layers (TCLs) form ARs and undergo xylogenesis under the same auxin plus cytokinin input. The aim of this research was to investigate SHR, SCR, AUX1 and LAX3 involvement in AR formation and xylogenesis in intact hypocotyls and stem TCLs in arabidopsis. Methods Hypocotyls of scr-1, shr-1, lax3, aux1-21 and lax3/aux1-21 Arabidopsis thaliana null mutant seedlings grown with or without auxin plus cytokinin were examined histologically, as were stem TCLs cultured with auxin plus cytokinin. SCR and AUX1 expression was monitored using pSCR::GFP and AUX1::GUS lines, and LAX3 expression and auxin localization during xylogenesis were monitored by using LAX3::GUS and DR5::GUS lines. Key Results AR formation was inhibited in all mutants, except lax3. SCR was expressed in pericycle anticlinally derived AR-forming cells of intact hypocotyls, and in cell clumps forming AR meristemoids of TCLs. The apex was anomalous in shr and scr ARs. In all mutant hypocotyls, the pericycle divided periclinally to produce xylogenesis. Xylary element maturation was favoured by auxin plus cytokinin in shr and aux1-21. Xylogenesis was enhanced in TCLs, and in aux1-21 and shr in particular. AUX1 was expressed before LAX3, i.e. in the early derivatives leading to either ARs or xylogenesis. Conclusions AR formation and xylogenesis are developmental programmes that are inversely related, but they involve fine-tuning by the same proteins, namely SHR, SCR and AUX1. Pericycle activity is central for the equilibrium between xylary development and AR formation in the hypocotyl, with a role for AUX1 in switching between, and balancing of, the two developmental programmes. PMID:25617411

  11. Methodology for producing 100 tons of fuel peat for a cement plant test burn. Metodologia para producir 100 toneladas de turba combustible para una prueba de quema en uns planta de cemento

    SciTech Connect

    Allen, A.B.; Malavassi, L.; Ramirez, O.; Thayer, G. , Plymouth, NC; RECOPE, San Jose; Los Alamos National Lab., NM )

    1989-05-01

    As a part of the Agency for International Development-funded cooperative project between Los Alamos and Costa Rica, the burning characteristics of Costa Rican peat were to be tested in an application. The cement plant owned by Industria National de Cemento in Cartago has a capability to handle solid fuel and was chosen for the burn demonstration. The Jungle No. 1 Peat Deposit near El Cairo was chosen as the site of the peat excavation. This peat production methodology study covers project site selection, installation of an access road and clearing of the jungle vegetation, removal of an upper layer of organic peat, excavation of fuel-grade peat, transport of the peat to the drying site, and drying and stockpiling of the finished product. As of this date the peat removal for the demonstration project has been started, and a description of the operation is included as an appendix to this paper. 10 figs.

  12. Prediction uncertainty of plume characteristics derived from a small number of measuring points

    NASA Astrophysics Data System (ADS)

    French, H. K.; van der Zee, S. E. A. T. M.; Leijnse, A.

    A small number of measuring points may inflict a bias on the characterisation of flow and transport based on field experiments in the unsaturated zone. Simulation of pure advective transport of a Gaussian plume through a setup of 30 regularly placed measuring points revealed regular temporal fluctuations about the real spatial moments. An irregular setup predicted both irregular fluctuations and larger discrepancies from the real value. From these considerations, a regular setup is recommended. Spatial moments were sensitive to the plume size relative to the distance between individual measuring points. To reduce prediction errors of the variance, the distance between the measuring points should be less than twice the standard deviation of the examined plume. The total size of the setup should cover several standard deviations of the plume to avoid mass being lost from the monitored area. Numerical simulations of a dispersing plume (comparing calculations based on 9000 nodes with 30 measuring points) revealed that vertical and horizontal centres of mass were predicted well at all degrees of heterogeneity, and the same was the case for horizontal variances. Vertical variances were more susceptible to prediction errors, but estimates were of the same order of magnitude as the real values. Résumé Lorsque l'on cherche à caractériser l'écoulement et le transport à partir d'expériences de terrain dans la zone saturée, il arrive qu'un petit nombre de points introduisent un biais. La simulation d'un transport purement advectif d'un panache gaussien au travers d'un ensemble de 30 points de mesures espacés régulièrement fait apparaître des variations temporelles régulières autour des moments spatiaux réels. Un ensemble irrégulier conduit à prédire à la fois des variations irrégulières et de plus grandes divergences par rapport à la valeur réelle. A partir de ces constations, un ensemble régulier est recommandé. Les moments spatiaux sont apparus sensibles à la dimension du panache en fonction de la distance entre les différents points de mesure. Afin de réduire les erreurs de prédiction de la variance, la distance entre les points de mesure doit être inférieure au double de l'écart-type du panache examiné. La dimension totale de l'ensemble doit couvrir une étendue de plusieurs écarts-types du panache pour éviter qu'une partie de la matière échappe à la zone surveillée. Des simulations numériques du panache en dispersion (les calculs de comparaison sont basés sur 9000 nœuds avec 30 points de mesure) montrent que le centre vertical et le centre horizontal de la matière dispersée ont été bien prédits à tous les degrés d'hétérogénéité, de même que pour les variances horizontales. Les variances verticales ont été plus sensibles aux erreurs de prédiction, mais les estimations étaient du même ordre de grandeur que les valeurs réelles. Resumen Un número pequeño de puntos de medida puede producir un sesgo en la caracterización en campo del flujo y transporte de solutos en la zona no saturada. La simulación de transporte advectivo (no difusivo) de un penacho Gaussiano a travs de un conjunto de 30 puntos de medida regularmente distribuidos revelan fluctuaciones temporales regulares de los momentos espaciales del penacho. Una distribución irregular de puntos de medida predijo a su vez fluctuaciones irregulares, más alejadas de la realidad, por lo que se recomienda el uso de esquemas de muestreo regulares. Los momentos espaciales fueron sensibles a la relación entre tamaño del penacho y distancia entre puntos de medida. Para reducir los errores en la predicción de la varianza, la distancia entre puntos de observación debe ser menor que dos veces la desviación estándar del penacho. El tamaño del área muestreada debe cubrir varias desviaciones estándar del penacho para evitar perder parte de la masa. Las simulaciones numricas en un penacho dispersivo, comparando los cálculos basados en 9000 nudos con las 30 medidas, mostraron que las posiciones de los centros de masa y las varianzas en dirección horizontal se predijeron bien independientemente del grado de heterogeneidad. Las varianzas verticales, sin embargo, fueron más susceptibles a errores de predicción, pero las estimaciones eran del mismo orden de magnitud que los valores reales.

  13. Diet of a sigmodontine rodent assemblage in a Peruvian montane forest

    PubMed Central

    Sahley, Catherine Teresa; Cervantes, Klauss; Pacheco, Victor; Salas, Edith; Paredes, Diego; Alonso, Alfonso

    2015-01-01

    Knowledge of feeding habits of small rodents is necessary for understanding food webs, trophic structure, and plant–animal interactions in Neotropical forests. Despite several studies that have investigated community structure and feeding behavior of rodents, large gaps remain in our understanding of their guild occupancy. Our objective was to investigate the diets of 7 species of small (< 100g) sympatric sigmodontine rodents in a high (3,500 m) Andean montane rainforest in Peru. We qualitatively and quantitatively assessed diet items in fecal samples from livetrapped rodents from 2009 to 2012. Frequency data for 4 diet categories indicated that all 7 species of rodents contained 4 diet categories in fecal samples: arthropods (88%), remains of leaves and fibers from plants (61%), intact seeds (with or without fruit pulp; 50%), and mycorrhizal spores (45%). Omnivory was found to be a strategy used by all species, although contingency table analysis revealed significant differences among and within species in diet categories. Cluster analysis showed 2 main groupings: that of the Thomasomys spp. plus Calomys sorellus group which included high amounts of intact seeds and plant parts in their fecal samples, and those of the genera Akodon, Microryzomys, Oligoryzomys, which included a greater proportion of arthropods in their fecal samples, but still consumed substantial amounts of fruit and plant parts. Intact seed remains from at least 17 plant species (9 families) were found in fecal samples. We concluded that this assemblage of sigmodontine rodents is omnivorous but that they likely play an important role as frugivores and in seed dispersal in tropical montane forests in Peru. El conocimiento de los hábitos alimenticios de roedores pequeños es necesario para comprender cadenas alimenticias, estructura trófica, e interacciones planta-animal en los bosques neotropicales. A pesar de que numerosos estudios han investigado la estructura de comunidades y el comportamiento de forrajeo en roedores, aún existen grandes vacíos en nuestra comprensión de sus gremios tróficos. Nuestro objetivo fue investigar las dietas de siete especies de pequeños (< 100 g) roedores sigmodontinos simpátricos en un bosque montano andino a 3.500] m en Perú. Cualitativamente y cuantitativamente evaluamos la dieta en muestras fecales de roedores capturados entre el 2009 y el 2012. Datos de frecuencia para cuatro categorías de dieta indicaron que las siete especies de roedores consumieron cuatro categorías de dieta: artrópodos (88%), pedazos de hojas y fibras de plantas (61%), semillas intactas (con o sin pulpa de frutos; 50%), y esporas de micorrizas (45%). Omnivoría fue la estrategia utilizada por todas las especies, aunque el análisis con tablas de contingencia reveló diferencias significativas entre y dentro de especies en categorías de dieta. El análisis de agrupación presentó 2 grupos principales: el grupo Thomasomys spp. y Calomys sorellus, que incluye una gran proporción de semillas intactas, y partes de plantas en las muestras fecales y el grupo que incluye los géneros Akodon, Microryzomys y Oligoryzomys, el cual incluyó una proporción mayor de artrópodos en sus muestras fecales, pero con niveles altos de semillas intactas. Semillas intactas de al menos 17 especies de plantas (9 familias) fueron encontradas en las muestras fecales. Concluimos que este ensamble de roedores sigmodontinos es omnívoro y que probablemente las especies juegan un rol importante como frugívoros y en la dispersión de semillas en los bosques montanos tropicales en el Perú. PMID:26937050

  14. Medicinal ethnobotany in Huacareta (Chuquisaca, Bolivia)

    PubMed Central

    2012-01-01

    Background The aim of this study was to document the types of diseases treated by the use of medicinal plants, their main applications and also to have a report of the major diseases treated at the Hospital of San Pablo de Huacareta (Chuquisaca Bolivia). Methods We conducted semi-structured interviews on the use medicinal plants with 10 local informants, and categorized the kinds of diseases treated by traditional medicine. We obtained reports of cases treated at the Hospital of Huacareta in order to compare the use frequency of traditional medicine and allopathic medicine for the treatment of recurrent diseases in the area. Results Our survey identified 258 traditional medicine uses, spanning a total of 13 diseases categories and including 91 native and exotic plant species and one unidentified sample plant type. Gastrointestinal disorders (55%) were most frequently treated with medicinal plants, followed by afflictions of the musculoskeletal system (25%) and dermatological disorders (24%). Hospital information indicates that the most common diseases are acute respiratory infections (47%) and acute diarrheal diseases (37%). The herbal remedies were mostly used in the form of teas and decoctions. The informants used mainly native plant species, although exotic species has been introduced to the pharmacopoeia. Conclusions The treatment of gastrointestinal disorders is the primary objective of the medical ethnobotany of the inhabitants of Huacareta, while respiratory system diseases are mostly treated in the hospital. Looking at the data from the Hospital records we can infer that gastrointestinal disorders are among the most common diseases in the study area. For most respondents, traditional medicine is a reliable choice for the care of their illnesses. However, the preference of the population for either traditional medicine or allopathic medicine needs to be clarified in future comparative studies to obtain more convincing results. The results presented can be used as a base for subsequent work related to traditional medicine and its contribution to allopathic medicine in San Pablo de Huacareta. Resumen Introducción El objetivo del presente estudio fue documentar los tipos de enfermedades tratadas mediante el uso de plantas medicinales, sus aplicaciones principales y también tener un reporte de las enfermedades mayormente atendidas en el Hospital de San Pablo de Huacareta (Chuquisaca, Bolivia). Métodos Se realizaron encuestas semiestructuradas a 10 informantes locales anotando los usos atribuidos a sus plantas medicinales, se agruparon las plantas por categorías de enfermedades tratadas en la medicina tradicional. Se obtuvieron reportes de casos tratados en el Hospital de Huacareta para poder relacionar el tratamiento de enfermedades recurrentes en la zona entre la medicina tradicional y la medicina occidental. Resultados Se reportaron 91 especies nativas y exóticas, además de un espécimen indeterminado exótico que intervienen en un total de 258 aplicaciones medicinales, las cuales son empleadas en un total de 13 categorías de enfermedades. Los desórdenes gastrointestinales (55%) son mayormente tratados mediante plantas medicinales, seguidas de las afecciones al sistema esqueleto-muscular (25%) y enfermedades dermatológicas (24%). La información del Hospital indica que las enfermedades más frecuentes son Infecciones Respiratorias Agudas (47%) y Enfermedades Diarreicas Agudas (37%). Los remedios vegetales se emplean en forma de infusiones y cocciones principalmente. Se emplean mayormente plantas nativas, también se introdujo en la farmacopea médica el uso de plantas exóticas al lugar. Conclusiones El tratamiento de trastornos gastrointestinales constituye el objetivo primordial de la etnobotánica médica de los habitantes de Huacareta, las enfermedades del sistema respiratorio, son mayormente tratadas en el Hospital. Observando los datos del libro de consultas del Hospital, se puede inferir que los desórdenes gastrointestinales están entre las enfermedades más frecuentes en el área estudiada. Para la mayoría de los entrevistados, la medicina tradicional es una opción confiable para la atención de sus enfermedades. Sin embargo, la preferencia de los habitantes entre la medicina tradicional y la medicina alopática podría ser clarificada a partir de futuros estudios comparativos que permitan obtener resultados más convincentes. Los resultados expuestos pueden ser usados como una base de datos para posteriores trabajos relacionados a la medicina tradicional y su contribución con la medicina alopática en San Pablo de Huacareta. PMID:22856877

  15. Parent-adolescent communication in foster, inter-country adoptive, and biological Italian families: Gender and generational differences.

    PubMed

    Rosnati, Rosa; Iafrate, Raffaella; Scabini, Eugenia

    2007-02-01

    There is a paucity of studies aimed at comparing how parents and children in different family structures cope with the challenges posed by the adolescence transition; in particular, there are few studies aimed at comparing adoptive and foster families. In order to partially fill this gap, the principal aims of the present study were to verify whether there are differences in parent-child communication among foster, intercountry adoptive, and biological families according to the adolescents' gender, and to compare the perceptions of parents and adolescents concerning parent-child communication. Data were elaborated on two levels: a generational level (adolescent's and his/her parents' perceptions among the three family groups) and a dyadic level (mother-child and father-child perceptions). The sample was composed of 276 Italian families with adolescents aged between 11 and 17 (81 foster, 98 international adoptive, and 97 biological families). Subjects (mothers, fathers, and children) filled out a questionnaire including the Parent-Adolescent Communication Scale (Barnes & Olson, 1985 ). Results highlighted that in foster families, parent-child communication showed more difficulties from both the adolescent's and the parents' point of view. Adoptive adolescents, however, reported a more positive communication with both their parents than did their peers living in biological and foster families. At a dyadic level, some differences emerged among the three groups. In biological families, a more pronounced distance emerged between parents and children. In adoptive families, father and adolescent shared more similar perceptions, whereas a significant discrepancy emerged between mother and child. A higher level of perceptual congruence between adolescents and parents was found in foster families. Gender differences were also seen: Mothers experienced a more open communication with their children than did fathers, and adolescents, and above all females, communicated better with their mothers than with their fathers in all three family groups. Il existe peu d'études qui visent à comparer comment les parents et les enfants, dans différentes structures familiales, composent avec les défis amenés par la transition à l'adolescence; en particulier, il existe peu d'études qui visent à comparer les familles adoptives et les familles d'accueil. Dans le but de combler en partie cette lacune, les principaux buts de la présente étude étaient de vérifier s'il existe des différences dans la communication parent-enfant entre les familles d'accueil, les familles adoptives (adoption entre pays) et les familles biologiques en fonction du sexe des adolescents et de comparer les perceptions des parents et des adolescents au sujet de la communication parent-enfant. Les données ont été élaborées à deux niveaux: un niveau générationnel (les perceptions de l'adolescent et de son parent parmi les trois groupes familiaux) et un niveau dyadique (perceptions mère-enfant et père-enfant). L'échantillon était composé de 276 familles italiennes avec adolescents entre 11 et 17 ans (81 familles d'accueil, 98 familles adoptives internationales et 97 familles biologiques). Les participants (mères, pères et enfants) ont complété un questionnaire incluant le «Parent-Adolescent Communication Scale (Barnes & Olson, 1985 ). Les résultats ont souligné que, dans les familles d'accueil, la communication parent-enfant a montré plus de difficultés à la fois du point de vue de l'adolescent et du point du parent. Cependant, les adolescents adoptifs ont évalué leur communication avec leurs mères et pères comme étant plus positive en comparaison à leurs pairs vivant dans des familles d'accueil et dans des familles biologiques. A un niveau dyadique, quelques différences ont émergé entre les trois groupes. Dans les familles biologiques, une distance plus prononcée a émergé entre les parents et les enfants. Dans les familles adoptives, le père et l'adolescent partageaient des perceptions similaires, tandis qu'une différence significative a émergé entre la mère et l'enfant. Un plus grand niveau de congruence perceptuelle entre les adolescents et les parents a été trouvé dans les familles d'accueil. Des différences entre les sexes ont aussi apparu: en comparaison aux pères, les mères ont expérimenté une communication plus ouverte avec leurs enfants et les adolescents, surtout les filles, communiquaient mieux avec leurs mères qu'avec leurs pères dans les trois groupes familiaux. Son escasos los estudios que se han propuesto comparar cómo los padres e hijos pertenecientes a diferentes estructuras familiares afrontan los retos que impone la transición a la adolescencia; en particular, pocos estudios comparan las familias adoptivas y las que ejercen el cuidado temporal. Para subsanar parcialmente esta deficiencia, los propósitos principales de el presente estudio fueron verificar si difiere la comunicación padres-hijos entre familias que ejercen cuidado temporal, aquéllas adoptivas entre países, y biológicas de acuerdo con el sexo del adolescente, y comparar las percepciones de los padres y de los adolescentes en cuanto a la comunicación padres-hijo. Los datos se analizaron en dos niveles: un nivel de generaciones (las percepciones del adolescente y de sus padres entre los tres grupos de familias) y un nivel de díadas (las percepciones madre-hijo y padre-hijo). Doscientas setenta y seis familias italianas con adolescentes entre 11 y 17 años de edad (81 familias de cuidado temporal, 98 adoptivas internacionalmente y 97 biológicas) constituyeron la muestra. Los participantes (madres, padres e hijos) respondieron a un cuestionario que incluía la Escala de Comunicación Padre-Adolescente (Barnes & Olson, 1985 ). Los resultados resaltan más dificultades en la comunicación padres-hijo en las familias que ejercen cuidado temporal, tanto desde la perspectiva del adolescente como de los padres. En tanto que los adolescentes adoptados perciben una comunicación más positiva que la de sus compañeros que viven en familias biológicas y de cuidado temporal. En el nivel de díadas, surgieron algunas diferencias entre los tres grupos. En las familias biológicas, se observó una distancia más pronunciada entre padres e hijos. En las familias adoptivas, el padre y el adolescente comparten percepciones más similares, mientras que discrepan significativamente madre e hijo. Se encontró un nivel mayor de congruencia perceptual entre los adolescentes y sus padres en las familias de cuidado temporal. En cuanto a diferencias de género, las madres experimentan una comunicación más abierta con sus hijos en comparación con los padres, y los adolescentes, sobretodo las mujeres, se comunican mejor con sus madres que con sus padres en los tres grupos de familias. PMID:24274778

  16. Planificación Neuroquirúrgica con Software Osirix

    PubMed Central

    Jaimovich, Sebastián Gastón; Guevara, Martin; Pampin, Sergio; Jaimovich, Roberto; Gardella, Javier Luis

    2014-01-01

    Introducción: La individualidad anatómica es clave para reducir el trauma quirúrgico y obtener un mejor resultado. Actualmente, el avance en las neuroimágenes ha permitido objetivar esa individualidad anatómica, permitiendo planificar la intervención quirúrgica. Con este objetivo, presentamos nuestra experiencia con el software Osirix. Descripción de la técnica: Se presentan 3 casos ejemplificadores de 40 realizados. Caso 1: Paciente con meningioma de la convexidad parasagital izquierda en área premotora; Caso 2: Paciente con macroadenoma hipofisario, operada previamente por vía transeptoesfenoidal en otra institución con una resección parcial; Caso 3: Paciente con lesiones en pedúnculo cerebeloso medio bilateral. Se realizó la planificación prequirúrgica con el software OsiriX, fusionando y reconstruyendo en 3D las imágenes de TC e IRM, para analizar relaciones anatómicas, medir distancias, coordenadas y trayectorias, entre otras funciones. Discusión: El software OsiriX de acceso libre y gratuito permite al cirujano, mediante la fusión y reconstrucción en 3D de imágenes, analizar la anatomía individual del paciente y planificar de forma rápida, simple, segura y económica cirugías de alta complejidad. En el Caso 1 se pudo analizar las relaciones del tumor con las estructuras adyacentes para minimizar el abordaje. En el Caso 2 permitió comprender la anatomía post-operatoria previa del paciente, para determinar la trayectoria del abordaje transnasal endoscópico y la necesidad de ampliar su exposición, logrando la resección tumoral completa. En el Caso 3 permitió obtener las coordenadas estereotáxicas y trayectoria de una lesión sin representación tomográfica. Conclusión: En casos de no contar con costosos sistemas de neuronavegación o estereotáxia el software OsiriX es una alternativa a la hora de planificar la cirugía, con el objetivo de disminuir el trauma y la morbilidad operatoria. PMID:25165617

  17. Revista Interamericana de Educacion de Adultos, 2003 (Interamerican Review of Adult Education, 2003).

    ERIC Educational Resources Information Center

    Guerra, Alfonso Rangel, Ed.

    2003-01-01

    This journal offers a collection of Spanish-language articles, including: "Educacion a Distancia y Uso de las Tecnologias: Experiencias Desafios y Oportunidades Educativas para Jovenes y Adultos" (Ma. Mercedes Ruiz); "Volver a a Educacion Fundamental? Notas para una Arquelogia de los Mandatos Fundacionales del CREFAL" (Jorge Rivas Diaz); "Una…

  18. Internet, Multimedia and Virtual Laboratories in a 'Third World' Environment.

    ERIC Educational Resources Information Center

    Monge-Najera, Julian Antonio; Rivas Rossi, Marta; Mendez-Estrada, Victor Hugo

    2001-01-01

    Describes the development of low-cost multimedia courses and materials for use on the Internet, as well as virtual laboratories, at the Universidad Estatal a Distancia (Costa Rica). Explains how simultaneous production of traditional printed materials and online courses, outsourcing, and the use of HTML and Java can reduce costs for developing…

  19. Analysis of the Use of Twitter as a Learning Strategy in Master's Studies

    ERIC Educational Resources Information Center

    Feliz, Tiberio; Ricoy, Carmen; Feliz, Slvora

    2013-01-01

    The present study analyses the use of Twitter in the course Social Media and Digital Learning, taught as part of a master's programme at Universidad Nacional de Educacion a Distancia (Spain). The main purpose of the use of this resource was to develop a learning community. This was implemented through the micro design of activities. A mixed

  20. Analysis of the Use of Twitter as a Learning Strategy in Master's Studies

    ERIC Educational Resources Information Center

    Feliz, Tiberio; Ricoy, Carmen; Feliz, Sálvora

    2013-01-01

    The present study analyses the use of Twitter in the course Social Media and Digital Learning, taught as part of a master's programme at Universidad Nacional de Educacion a Distancia (Spain). The main purpose of the use of this resource was to develop a learning community. This was implemented through the micro design of activities. A mixed…

  1. Estatuto del Docente: Modificaciones Introducidas entre el Mes de Junio de 1967 y Setiembre de 1970 (Teacher Regulations: Changes Made between June 1967 and September 1970).

    ERIC Educational Resources Information Center

    Ministerio de Cultura y Educacion, Buenos Aires (Argentina). Centro National de Documentacion e Informacion Educativa.

    This booklet contains the modifications made in the regulations governing the teaching profession in Argentina between June 1967 and September 1970. Regulations cover the qualifications and requirements for certification, promotion, and retirement and the mechanics for classification and advancement. (VM)

  2. Católicos, fidelidade conjugal e AIDS: entre a cruz da doutrina moral e as espadas do cotidiano sexual dos adeptos1

    PubMed Central

    Rios, Luis Felipe; de Aquino, Francisca Luciana; Muñoz-Laboy, Miguel; Oliveira, Cinthia; Parker, Richard

    2009-01-01

    Neste artigo discutimos a visão da Igreja Católica sobre sexualidade na interface com a epidemia do HIV/AIDS. Nossa reflexão está embasada em pesquisa etnográfica que envolveu dois meses de observação participante do cotidiano de católicos de um bairro popular da Região Metropolitana do Recife, além de contar com entrevistas a onze dos leigos engajados nos serviços religiosos da igreja do bairro e a oito sacerdotes que realizam seus trabalhos religiosos em outras localidades. Nelas abordamos diferentes temáticas relacionadas ao enfrentamento da epidemia da AIDS. Nesse contexto, conjugalidade e fidelidade se afiguram como importantes analisadores de como aqueles lidam com a epidemia, em uma variedade de re-descrições práticas e de re-interpretações conceptuais das assertivas do discurso moral religioso – ainda que, muitos impasses permaneçam em aberto em termos das prerrogativas da Igreja e seus possíveis rebatimentos na saúde sexual dos adeptos. PMID:21765650

  3. Transitioning to new child-care nutrition policies: nutrient content of preschool menus differs by presence of vegetarian main entrée.

    PubMed

    Turner-McGrievy, Gabrielle M; Hales, Sarah B; Baum, Angela C

    2014-01-01

    Children who attend child care outside the home may be at increased risk for developing obesity. In 2012, the South Carolina ABC Child Care program issued new standards for food and nutrition. The goal of our study (conducted June to December 2012) was to examine changes that occurred at a large, Columbia, SC, preschool during the implementation of the South Carolina ABC Child Care program standards using an observational design, including a survey of parents and nutrient analysis of menus. The nutrition content of menu items before (n=15 days; six of which were vegetarian) and after (n=15 days; six of which were vegetarian) implementation of the new standards was compared. In addition, parents (N=75) were surveyed to examine opinions and support for the changes. Independent samples t tests were used to compare nutrient values before and after menu changes and analysis of variance was used to compare pre- and post-change vegetarian menus and pre- and post-change nonvegetarian menus. There were no significant differences between before and after menus with the exception of a 0.3 cup/day increase in vegetables (P<0.05). Vegetarian menus after the revisions were significantly higher in fiber (13 ± 3 g) than postrevision nonvegetarian menus (11 ± 3 g; P<0.05) and lower in sodium (1,068 ± 207 mg) than postrevision nonvegetarian menus (1,656 ± 488 mg; P<0.05). Standards that received the most parental support were serving at least two vegetables (score of 8.7 on a scale of one to nine) and two fruits per day (score of 8.6) and implementing policies against staff using food as a reward or punishment (score of 8.6). The center-specific policy of only bringing healthy foods for celebrations received the lowest support (score of 5.8). Adding more vegetarian menu items has the potential to improve the nutrient content of menus while keeping energy intake, saturated fat, sodium, and cholesterol levels at a more optimum level. PMID:24144990

  4. Associação entre lipid accumulation product (LAP) e hirsutismo na síndrome do ovário policístico.

    PubMed

    Oliveira, Flávia Ribeiro de; Rezende, Mariana Bicalho; Faria, Nícolas Figueiredo; Dias, Tomás Ribeiro Gonçalves; Oliveira, Walter Carlos Santos de; Rocha, Ana Luiza Lunardi; Cândido, Ana Lúcia

    2016-02-01

    Objective Polycystic ovary syndrome (PCOS) is the most common endocrine metabolic disorder in women between menarche and menopause. Clinical hyperandrogenism is the most important diagnostic criterion of the syndrome, which manifests as hirsutism in 70% of cases. Hirsute carriers of PCOS have high cardiovascular risk. Lipid accumulation product (LAP) is an index for the evaluation of lipid accumulation in adults and the prediction of cardiovascular risk. The aim of this study was to evaluate the association between LAP and hirsutism in women with PCOS. Methods This was a cross-sectional observational study of a secondary database, which included 263 patients who had visited the Hyperandrogenism Outpatient Clinic from November 2009 to July 2014. The exclusion criteria were patients without Ferriman-Gallwey index (FGI) and/or LAP data. We used the Rotterdam criteria for the diagnosis of PCOS. All patients underwent medical assessment followed by measurement and recording of anthropometric data and the laboratory tests for measurement of the following: thyroid-stimulating hormone, follicle-stimulating hormone, prolactin, total testosterone, sex hormone binding globulin, 17-α-hydroxyprogesterone (follicular phase), glycohemoglobin A1c, and basal insulin. In addition, the subjects underwent lipid profiling and oral glucose tolerance tests. Other laboratory measurements were determined according to clinical criteria. LAP and the homeostatic model assessment index (HOMA-IR) were calculated using the data obtained. We divided patients into two groups: the PCOS group with normal LAP (< 34.5) and the PCOS group with altered LAP (> 34.5) to compare the occurrence of hirsutism. For statistical analysis, we used SPSS Statistics for Windows® and Microsoft Excel programs, with descriptive (frequencies, percentages, means, and standard deviations) and comparative analyses (Student's t-test and Chi-square test). We considered relations significant when the p-value was ≤ 0.05. Results LAP was high in most patients (n = 177; 67.3%) and the FGI indicated that 58.5% of the patients (n = 154) had hirsutism. The analysis by LAP quartiles showed a positive correlation (p = 0.04) among patients with a high FGI and an upper quartile LAP (> 79.5) when compared with those with LAP < 29.0 (lower quartile). Conclusion This study demonstrated an association between high LAP and hirsutism. The FGI could represent a simple and low-cost tool to infer an increased cardiovascular risk in women with PCOS. PMID:26909772

  5. The Effect of Low Dose Irradiation and Grapefruit Extract on C. perfringens Growth from Spores in sous vide Processed Pork-Based Mexican Entrée

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sous vide, a common cooking method for meat and poultry products is widely used for providing ready-to-eat meals. Traditionally, these products have limited shelf life, ranging from 2 to 3 weeks. However, similar products may be stored for longer periods in the U.S. and other countries, requiring ad...

  6. Optimisation de l'émission du continuum femtoseconde de lumière blanche entre 600 nm et 800 nm

    NASA Astrophysics Data System (ADS)

    Ramstein, S.; Mottin, S.

    2005-06-01

    Un dispositif de spectroscopie avec résolution du temps de vol des photons en milieu diffus a été développé. Celui-ci repose sur l'utilisation d'un continuum de lumière blanche généré par focalisation d'un laser amplifié (830 nm, 1 kHz, 0.5 W, 170 fs) dans de l'eau déminéralisée. Afin d'optimiser spectralement et en puissance la source blanche sur la fenêtre spectrale 600 800 nm, une étude de la mise en forme spatio-temporelle avant autofocalisation de l'impulsion laser par le milieu a été menée. Cette mise en forme est effectuée de manière spatiale en changeant la focale de la lentille de focalisation et de manière temporelle en changeant le taux de compression de l'impulsion. L'étude montre que le cône de lumière émise possède plus de puissance dans la fenêtre spectrale d'intérêt pour des focales longues. Sur la fenêtre 600-800 nm, le rendement énergétique intégré varie de 5%, avec une focalef=6cm, à 15%, avec une focale f = 30 cm. La mise en forme temporelle montre des effets similaires avec les mêmes ordres de grandeur.

  7. La Linguistica Aplicada a la Relacion Paradigmatica entre los Verbos "Ser" y "Estar" (Linguistics Applied to the Paradigmatic Relationship between the Verbs "Ser" and "Estar")

    ERIC Educational Resources Information Center

    Marchetti, Magda Ruggeri

    1977-01-01

    Speakers of Italian often have problems mastering Spanish because they erroneously believe its great similiarity to Italian makes it easy to learn. One of the fundamental problems is the lack of ability to choose the correct verb, "ser" or "estar," both equivalents of the Italian "essere." (Text is in Spanish.) (CFM)

  8. Make the Reading-Writing Connection: Tips for Parents of Young Learners = Haga el enlace entre lectura y escrita: Consejos para padres de jovenes que estan aprendiendo.

    ERIC Educational Resources Information Center

    International Reading Association, Newark, DE.

    This brochure offers parents tips on helping their children connect writing with reading. It begins by noting that preschool children often want to scribble on paper, scribbles which sometimes represent a story. It suggests making space in the home for literacy, and encouraging early efforts. The brochure then offers four brief activities for…

  9. Psychological Correlates of the Transmission and Acceptance of Rumors about AIDS = Correlates Psychologiques Entre la Transmission et l'Acceptation des Rumeurs sur le SIDA.

    ERIC Educational Resources Information Center

    Kimmel, Allan J.

    Public reactions to the Acquired Immune Deficiency Syndrome (AIDS) crisis are accompanied by the sorts of emotional and cognitive factors that have been identified by researchers as predictors of rumor generation and transmission. The present investigation attempted to ascertain the extent that various subjective factors (including anxiety,…

  10. Relación física entre el cúmulo abierto Hogg 15 y la estrella Wolf-Rayet WR 47

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Bica, E.; Santos, J. F. C., Jr.; Clariá, J. J.

    We revise the fundamental parameters of the faint open cluster Hogg 15, for which two recent colour-magnitude diagram (CMD) studies have obtained significantly different ages (Sagar et al. 2001, MNRAS, 327, 23; Piatti & Clariá 2001, A&A, 370, 931). In the present study, we combine a series of methods trying to constrain age, together with other fundamental parameters. We employ spatial extractions to construct the CMDs, and the cluster integrated spectrum to compare the latter with those of templates of known age. For Hogg 15 we derive an age of (20 ± 10) Myr, a reddening of (1.10 ± 0.05) mag, and a distance of (3.1 ± 0.5) kpc. We conclude that the estimation of an older age in the study of Piatti & Clariá can be accounted for in terms of main sequence/turnoff curvature being blurred in the CMDs, an effect mainly caused by field contamination. To clarify the issue of whether the Wolf-Rayet star HDE 311884 (WR 47), known to be a WN6 + O5V binary system, is associated or not with Hogg 15, we discuss its fundamental parameters, particularly its distance. Based on the WR 47 spectrum and available photometry, we assume that the underestimated distance implied by the Hipparcos parallax (216 pc) is affected by its binary character. By comparing the WR 47 spectrum with those of WR stars of a similar type, we conclude that WR 47 is not affected by a E(B-V) colour excess much higher than that associated with Hogg 15, namely E(B-V) = 1.10. On the basis of the WR 47's resulting distance of (5.2 ± 0.9) kpc, which largely surpasses that of the cluster, we conclude that WR 47 is not related to Hogg 15 from the point of view of origin, since the cluster and the star do not belong to the same formation event.

  11. Vinculación Física entre Super Cáscaras de Hidrógeno Neutro y Formación Estelar Reciente

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Arnal, E. M.

    Many of the known galactic HI supershells (SCHI) may have been formed by the combined effects of stellar winds and supernovae explotions. Having most of them dynamic lifetimes of a few times 10^7 yr, these huge structures are likely to outlive the stars that gave rise to them. Hence, these SCHI may be used as fossil records of the Milky Way star formation history. Furthermore, along their evolution SCHI may trigger star formation. In this paper we analyze the genetic link put forward by McClure-Griffiths et al. (2002) between the OB association Cen OB1 and the SCHI GSH305+01-24. From our study we conclude that GSH305+01-24 may not represent a real physical structure. Instead, we believe that this structure is best represented by two unrelated huge HI shells. The role played by Cen OB1 in powering one of these HI shells is unclear for the time being. FULL TEXT IN SPANISH.

  12. Contribution à l'analyse des inter-relations entre activités humaines et variabilité climatique : cas du Sud forestier ivoirien

    NASA Astrophysics Data System (ADS)

    Yao, Télésphore Brou; Servat, Eric; Paturel, Jean-Emmanuel

    1998-12-01

    The South Ivorian Forest has suffered a large rainfall deficit for 25 years. At the same time, it has been noticed that the movement of the coffee and cocoa production seems concomitant with that of the isohyets during recent decades. The variations in albedo and rainfall gradient seem to be linked to the significant changes to the forest cover. These could affect precipitation locally.

  13. Psychological Correlates of the Transmission and Acceptance of Rumors about AIDS = Correlates Psychologiques Entre la Transmission et l'Acceptation des Rumeurs sur le SIDA.

    ERIC Educational Resources Information Center

    Kimmel, Allan J.

    Public reactions to the Acquired Immune Deficiency Syndrome (AIDS) crisis are accompanied by the sorts of emotional and cognitive factors that have been identified by researchers as predictors of rumor generation and transmission. The present investigation attempted to ascertain the extent that various subjective factors (including anxiety,

  14. Etude comparative entre l'astrolabe dit "carolingien" et l'astrolabe d'Abù-Bakr ibn Yusuf de Toulouse.

    NASA Astrophysics Data System (ADS)

    D'Hollander, R.

    This article is a comparative study that is essentially technical. It is based on very careful measurements of an accuracy of up to one tenth of a millimetre carried out on the plates and retes of the two astrolabes examined by the writer. Abù-Bakr ibn Yusuf's astrolabe is in the Musée Paul Dupuy in Toulouse. It was made in 1216-17 in Marrakech.

  15. Etude, par principes premiers, des effets de la correlation entre electrons sur les proprietes electroniques et magnetiques de polymeres pontes et de supraconducteurs a haute temperature critique

    NASA Astrophysics Data System (ADS)

    Pesant, Simon

    Description of complex systems by Density functional theory is treated in this thesis. First, the Density functional theory and a few functionals used to simulate cristals are presented. Specifically, the LDA and GGA functionnals are described and their limits are exposed. Furthermore, the Hubbard model as well as the LDA+U functionnal are addressed in this chapter. These methods enable the study of highly correlated materials. Then, results obtained on polymers are summarized in two articles. The first one treats the band gap variation of ladder-type polymers compared to non ladder type ones. The second article considers small band gap polymers. In this case, it will be shown that an hybrid functional, which contains exact exchange, is required to describe the electronic properties of the polymers under study. Finally, the last chapter address the study of cuprates superconductors. The LDA+U can account for the localization of electrons in copper orbitals. Consequently, a study of the impact of this functionnal on electronic properties of cuprates is conducted. The chapter is ended by an article treating magnetic orders in doped La 2CuO4. Supplementary materials of the second article and a description of the theory of superconductivity of Bardeen, Cooper and Schrieffer are put in annex. Keywords : Electronic correlation, DFT, LDA+U, cuprates, polymers, magnetic orders

  16. Thriving Together: Connecting Rural School Improvement and Community Development = Prosperando juntos: La conexion entre el mejoramiento de la escuela rural y el desarrollo comunitario.

    ERIC Educational Resources Information Center

    Boethel, Martha

    Available in English or Spanish, this resource guide aims to help rural schools and communities learn ways of supporting each other so that both can thrive. Background information and basic tools are provided for starting a joint school-community development effort. Chapters contain: (1) outline of the guide and statement of beliefs about…

  17. Entrée atmosphérique de micrométéorites poreuses chargées en matière organique.

    NASA Astrophysics Data System (ADS)

    Bonny, P.; Balageas, D.; Devezeaux, D.; Maurette, M.

    A high ratio (≡20 - 30%) of unmelted to melted chondritic micrometeorites has been observed in new collections of Greenland and Antartica micrometeorites. The constant value of this ratio in the size range 100 μm - 1000 μm cannot be predicted from previous models, describing the ablation of "inert" micrometeorites in the atmosphere. These micrometeorites cannot be related to known classes of meteorites.

  18. Previniendo el Uso de Drogas entre Ninos y Adolescentes: Una Guia Basada en Investigaciones (Preventing Drug Use among Children and Adolescents: A Research-Based Guide).

    ERIC Educational Resources Information Center

    Sloboda, Zili; David, Susan L.

    This question and answer guide provides an overview of the research on the origins and pathways of drug abuse, the basic principles derived from effective drug abuse prevention research, and the application of research results to the prevention of drug use among young people. The basic principles derived from drug abuse prevention research are…

  19. Modelo Crosscultural de Pasantias para Lideres de la Educacion: Cooperacion entre Estados Unidos y Venezuela (Designing an Effective School Administrator Internship Program: United States and Venezuela Cooperation).

    ERIC Educational Resources Information Center

    Serafin, Ana Gil; Thompson, Eugene W.

    A model was developed of an internship program designed to give valuable cross-cultural experience to school administrators in training at universities in the United States and Venezuela. A naturalistic approach was used to develop the model. Leading school administrators and educational leadership theorists in both countries were interviewed by…

  20. Entre dois mundos: vida quotidiana de criancas portuguesas na america [Between Two Worlds: The Daily Life of Portuguese Children in America].

    ERIC Educational Resources Information Center

    de Meneses, Fernando

    This Portuguese reader with accompanying teacher's guide describes the culture shock that Portuguese children and their families face when they immigrate to North America. The reader is divided into 75 short stories about the families that come from the rural areas of Portugal where there has been little industrialization. The purpose of the…

  1. En la búsqueda de características en eyecciones coronales de masa que discriminen entre dos paradigmas físicos en modelos de ECMs

    NASA Astrophysics Data System (ADS)

    Paissan, G.; Stenborg, G.; Rovira, M.

    Se conocen tres diferentes fenómenos de gran escala que ocurren en la atmósfera solar, denominados eyecciones coronales de masa (ECMs), protuberancias eruptivas y grandes fulguraciones de dos bandas. Estos fenómenos están estrechamente relacionados y podrían ser distintas manifestaciones de un único proceso físico. Las ECMs son definidas como eyecciones de gran escala de masa y flujo magnético desde la baja corona al espacio interplanetario. Desde su descubrimiento en los '70, muchos modelos han sido propuestos para explicar su origen y evolución. La explicación física de las ECMs es un tema de debate intenso. No obstante, los modelos pueden sintetizarse en dos grandes grupos: 1) los modelos de inyección de flujo y 2) los modelos de almacenamiento y liberación. En este trabajo, se presentan los estudios realizados con una serie de eventos observados con el coronógrafo MICA (Mirror Coronograph for Argentina), el telescopio en H-alfa HASTA (H-alpha Solar Telescope for Argentina) y los coronógrafos C2 y C3 de la sonda SOHO (Solar and Heliospheric Observatory). Los eventos que pudieron ser identificados como ECMs son contrastados dentro del esquema de los dos paradigmas teóricos propuestos.

  2. Relación entre la orientación de Nebulosas Planetarias y el campo magnético galáctico

    NASA Astrophysics Data System (ADS)

    Weidmann, W.; Díaz, R. J.; Carranza, G.

    Un estudio detallado de las orientaciones diferenciales de nebulosas planetarias en todo el cielo sugiere fuertemente una relación con la dirección de los campos magnéticos de origen galáctico, determinados en la polarización de estrellas de campo. Esto da consistencia a la hipótesis de que la orientación de las nebulosas planetarias ovaladas es inducida, al menos parcialmente, por el campo magnético general de la Vía Láctea.

  3. L'espace du mouvement: Une analyse des conflits dans les interactions entre institutrice et eleves d'une ecole maternelle

    NASA Astrophysics Data System (ADS)

    Galvão, Izabel

    1995-01-01

    The research described in this article, winner of the Gottfried Hausmann Prize for 1994, was carried out in a kindergarten in São Paolo, Brazil, using the theory developed by Henri Wallon. The aim was to examine how primary school children are affected in their development by: (a) unnecessary restrictions placed on their physical movements during lessons; and (b) failure to organize the classroom space in a way that assists the learning process. The author concludes that these factors lead to tensions in the classroom which could be avoided through a different approach to movement and space.

  4. La Littérature De Jeunesse Entre Normes Pédagogiques Et Littéraires : Le Cas Des Pays Francophones D'afrique

    NASA Astrophysics Data System (ADS)

    Attikpoé, Kodjo

    2007-01-01

    YOUTH LITERATURE IN THE CONTEXT OF PEDAGOGIC AND LITERARY NORMS: THE FRENCH-SPEAKING COUNTRIES OF AFRICA - There are two approaches to children's and youth literature, one didactic, the other aesthetic. This gives rise to the following question: taking into account the fact that children's literature aspires to be a literary form in its own right, should more weight be attibuted to its aesthetic value when evaluating it? This paper examines this question - which has in the past been the subject of highly controversial discussions in the German-speaking regions - by focusing on youth literature in the French-speaking coutries of Africa. The pedagogic dimension cannot be ignored when considering this literary context because it is so much a part of the post-colonial dynamic. Youth literature in the French-speaking countries of Africa echoes current realities. Examples are used to demonstrate how literature can deal with vital questions without neglecting the literary aspect.

  5. Tools for evaluating Lipolexis oregmae (Hymenoptera: Aphidiidae) in the field: Effects of host aphid and host plant on mummy location and color plus improved methods for obtaining adults

    SciTech Connect

    Singh, R.; Hoy, M.A.

    2007-03-15

    Lipolexis oregmae Gahan was introduced into Florida in a classical biological control program directed against the brown citrus aphid, Toxoptera citricida (Kirkaldy), on citrus. Prior to evaluating distribution, host range, and potential nontarget effects of L. oregmae in Florida, we evaluated the role of other potential host aphids and host plants on mummy production and location. Under laboratory conditions, this parasitoid produced the most progeny on the target pest, the brown citrus aphid on citrus. This parasitoid, unlike the majority of aphidiids, did not produce mummies on any of the host plants tested when reared in black citrus aphid T. aurantii (Boyer de Fonscolombe) on grapefruit, spirea aphid Aphis spiraecola Patch on grapefruit and pittosporum, cowpea aphid A. craccivora Koch on grapefruit and cowpeas, or melon aphid A. gossypii Glover on grapefruit and cucumber. Thus, sampling for L. oregmae mummies of these host aphids and host plants must involve holding foliage in the laboratory until mummies are produced. This parasitoid requires high relative humidity to produce adults because no adults emerged when mummies were held in gelatin capsules, but high rates of emergence were observed when mummies were held on 1.5% agar plates. In addition, we compared the color of 6 aphid hosts and the color of mummies produced by L. oregmae when reared in them to determine if color of mummies could be used to identify L. oregmae . Mummy color varied between aphid hosts and tested host plants, and is not a useful tool for identifying L. oregmae for nontarget effects. (author) [Spanish] Lipolexis oregmae Gahan fue introducida en Florida por medio de un programa de control biologico clasico dirigido contra el afido pardo de los citricos, Toxoptera citricida (Kirkaldy), sobre Citrus. Prioritario a la evaluacion de la distribucion, el rango de los hospederos y los efectos potenciales de L. oregmae sobre los organismos que no son el enfoque de control en la Florida, nosotros evaluamos el papel de otras especies de afidos y plantas hospederas potenciales sobre la produccion y ubicacion de las momias. Bajo condiciones de laboratorio, este parasitoide produjo el mayor numero de progenies sobre la especie de plaga enfocada, el afido pardo de los citricos sobre Citrus . Este parasitoide, no como la mayoria de los afidiidos (Hymenoptera), no produjo momias sobre cualquiera de las plantas hospederas probadas cuando fue criado sobre el afido negro de los citricos, ( T. aurantii (Boyer de Fonscolombe)) en toronja, el afido spirea (Aphis spiraecola Patch) en toronja y pittosporum, el afido del caupi (A. craccivora Koch) en toronja y caupi o el afido del melon (A. gossypii Glover) en toronja y pepino. Asi, el muestreo para momias de L. oregmae de estas especies de afidos hospederos y plantas hospederas tiene que incluir el mantenimiento de follaje en el laboratorio hasta que se produzcan las momias. Este parasitoide requiere una alta humedad relativa para producir los adultos por que ningun adulto emergio cuando las momias fueron mantenidas en capsulas de gelatina, pero una tasa alta de emergencia de adultos fue observada cuando se mantuvo las momias en platos con agar al 1.5%. Ademas de esto, nosotros comparamos el color de 6 especies de afidos hospederos, asi como el color de las momias producidos por L. oregmae cuando fue criado sobre ellos para determinar si se puede usar el color de las momias para la identificacion de L. oregmae . El color de las momias varia entre las especies de afidos hospederos y las plantas hospederas probadas, por lo que no es una herramienta util para la identificacion de L. oregmae o para la evaluacion de su efecto sobre los organismos que no son el enfoque del control. (author)

  6. Trait differences between naturalized and invasive plant species independent of residence time and phylogeny

    PubMed Central

    Gallagher, R V; Randall, R P; Leishman, M R

    2015-01-01

    The ability to predict which alien plants will transition from naturalized to invasive prior to their introduction to novel regions is a key goal for conservation and has the potential to increase the efficacy of weed risk assessment (WRA). However, multiple factors contribute to plant invasion success (e.g., functional traits, range characteristics, residence time, phylogeny), and they all must be taken into account simultaneously in order to identify meaningful correlates of invasion success. We compiled 146 pairs of phylogenetically paired (congeneric) naturalized and invasive plant species in Australia with similar minimum residence times (i.e., time since introduction in years). These pairs were used to test for differences in 5 functional traits (flowering duration, leaf size, maximum height, specific leaf area [SLA], seed mass) and 3 characteristics of species’ native ranges (biome occupancy, mean annual temperature, and rainfall breadth) between naturalized and invasive species. Invasive species, on average, had larger SLA, longer flowering periods, and were taller than their congeneric naturalized relatives. Invaders also exhibited greater tolerance for different environmental conditions in the native range, where they occupied more biomes and a wider breadth of rainfall and temperature conditions than naturalized congeners. However, neither seed mass nor leaf size differed between pairs of naturalized and invasive species. A key finding was the role of SLA in distinguishing between naturalized and invasive pairs. Species with high SLA values were typically associated with faster growth rates, more rapid turnover of leaf material, and shorter lifespans than those species with low SLA. This suite of characteristics may contribute to the ability of a species to transition from naturalized to invasive across a wide range of environmental contexts and disturbance regimes. Our findings will help in the refinement of WRA protocols, and we advocate the inclusion of quantitative traits, in particular SLA, into the WRA schemes. Diferencia de Características entre Especies de Plantas Naturalizadas e Invasoras Independientes del Tiempo de Residencia y de la Filogenia Resumen La habilidad para predecir cuáles plantas exóticas harán la transición de naturalizadas a invasoras antes de su introducción a regiones nuevas es un objetivo clave para la conservación y tiene el potencial de incrementar la eficiencia de la evaluación de riesgo de hierbas (ERH). Sin embargo, múltiples factores contribuyen al éxito invasor de las plantas (p. ej.: características funcionales, características de cobertura, tiempo de residencia, filogenia) y todos deben considerarse simultáneamente para poder identificar correlaciones significativas del éxito invasor. Recopilamos en Australia 146 parejas de especies de plantas invasoras y naturalizadas emparejadas filogenéticamente (congéneres) y con tiempos de residencia mínima similares (es decir, el tiempo transcurrido desde su introducción en años). Estas parejas se usaron para probar diferencias en cinco características funcionales (duración de la floración, tamaño de la hoja, altura máxima, área específica de la hoja [AEH], masa de la semilla) y en tres características de cobertura nativa de las especies (ocupación de bioma, temperatura media anual y amplitud de pluviosidad) entre especies invasoras y naturalizadas. Las especies invasoras, en promedio, tuvieron una mayor AEH, periodos de floración más largos y fueron más altas que sus parientes congéneres naturalizadas. Las invasoras también exhibieron una mayor tolerancia a diferentes condiciones ambientales en su cobertura nativa, donde ocuparon más biomas y una mayor amplitud de pluviosidad y condiciones de temperatura que sus congéneres naturalizadas. Sin embargo, ni la masa de la semilla ni el tamaño de hoja difirieron entre las parejas de especies naturalizadas e invasoras. Un hallazgo relevante fue el papel de la AEH en la distinción entre las parejas naturalizadas e invasoras. Las especies con valores altos de AEH estuvieron asociadas típicamente con tasas mayores de crecimiento, pérdida rápida de volumen de material de hojas y periodos de vida más cortos que aquellas especies con AEH baja. Este conjunto de características puede contribuir a la habilidad de las especies para llevar a cabo la transición de naturalizada a invasora a lo largo de una amplia cobertura de contextos ambientales y regímenes de perturbación. Nuestros hallazgos ayudarán en la mejora de los protocolos de ERH, y abogamos por la inclusión de las características cuantitativas, en particular la AEH, en los esquemas de ERH. PMID:25369762

  7. When Did the Swahili Become Maritime?

    PubMed Central

    Fleisher, Jeffrey; Lane, Paul; LaViolette, Adria; Horton, Mark; Pollard, Edward; Quintana Morales, Eréndira; Vernet, Thomas; Christie, Annalisa; Wynne-Jones, Stephanie

    2015-01-01

    In this article, we examine an assumption about the historic Swahili of the eastern African coast: that they were a maritime society from their beginnings in the first millennium C.E. Based on historical and archaeological data, we suggest that, despite their proximity to and use of the sea, the level of maritimity of Swahili society increased greatly over time and was only fully realized in the early second millennium C.E. Drawing on recent theorizing from other areas of the world about maritimity as well as research on the Swahili, we discuss three arenas that distinguish first- and second-millennium coastal society in terms of their maritime orientation. These are variability and discontinuity in settlement location and permanence; evidence of increased engagement with the sea through fishing and sailing technology; and specialized architectural developments involving port facilities, mosques, and houses. The implications of this study are that we must move beyond coastal location in determining maritimity; consider how the sea and its products were part of social life; and assess whether the marine environment actively influences and is influenced by broader patterns of sociocultural organization, practice, and belief within Swahili and other societies. [maritime, fishing and sailing, long-distance trade, Swahili, eastern Africa] RESUMEN En este artículo, evaluamos la hipótesis de que los pueblos Swahili de la costa oriental africana fueron una sociedad marítima a partir del primer milenio E.C. Basados en información histórica y arqueológica, proponemos que la asociación de la sociedad Swahili con el mar incrementó considerablemente con el tiempo y se manifestó de una forma significativa particularmente desde principios del segundo milenio E.C. Utilizando teorías recientes sobre maritimidad en otras áreas del mundo, así como investigaciones sobre los Swahili, discutimos tres temas que marcan las diferencias del nivel de orientación marítima de esta sociedad costera entre el primer y segundo milenio. Éstas son la variabilidad y discontinuidad en la localización y permanencia de los asentamientos; evidencia de una conexión mayor con el mar a través de la tecnología de pesca y navegación; y desarrollos arquitectónicos especializados que incluyen instalaciones portuarias, mezquitas, y casas. Las implicaciones de este estudio indican que debemos considerar otros aspectos de una sociedad aparte de su localización costera para determinar su maritimidad. Hay que considerar cómo el mar y sus productos son parte de la vida social y evaluar si existe una influencia recíproca entre el ambiente marítimo y los patrones de organización sociocultural, las prácticas, y las creencias de los Swahili y otras sociedades. [marítimo, pesca y navegación, comercio a larga distancia, Swahili, África Oriental] PMID:25821235

  8. Potencial de Seqüestro de Carbono Atmosférico entre Diferentes Cultivares de Milho (Zea mays L.) sob Condiç o de Déficit Hídrico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a question concerning the role of agricultural practices on carbon sequestration enhancement. By producing biomass with agricultural crops and adding this residue to soil, it should act on the mitigation process of the greenhouse effect, especially CO2. The objectives of this study were to ...

  9. Le « Harcèlement Entre Pairs » À L'école élémentaire Tchèque: Une Question D'interprétation

    NASA Astrophysics Data System (ADS)

    Kohout-Diaz, Magdalena

    2008-07-01

    "PEER BULLYING" IN CZECH PRIMARY SCHOOLS: A QUESTION OF INTERPRETATION—This article questions adults' reports of an alleged increase in peer bullying at Czech primary schools. A survey on the school climate revealed that the pupils see it as a generally positive one and consider their relationships to be good. However, compared to France, their behaviour towards the adults is aggressive and rude. This apparent contradiction is linked to a conflict between the educational norms carried over from the old regime (behavioural control and conformism) and the new socio-economic paradigms (critical thinking and free enterprise). Public opinion, the media and a number of scientifically-questionable studies have drawn attention to the phenomenon of peer bullying ( šikana), and applied an imported concept to describe it ( school bullying). This makes it possible to avoid questioning the part played by the adults, the school and the researchers; justify segregating pupils from socially, culturally or economically disadvantaged backgrounds (Roma); and facilitate the country's socio-economic inclusion in the European Union by highlighting educational problems about whose nature there is general agreement.

  10. A Comparison of Chinese and Colombian University EFL Students Regarding Learner Autonomy (Comparación entre estudiantes universitarios de inglés chinos y colombianos con respecto a su autonomía como aprendices)

    ERIC Educational Resources Information Center

    Buendía Arias, Ximena Paola

    2015-01-01

    This research seeks to gain deeper understanding of learner autonomy in English as a Foreign Language students from different cultures through the identification and analysis of similarities and differences between Chinese and Colombian students from two public universities: Tianjin Foreign Studies University in China and Universidad Surcolombiana…

  11. Online Peer Feedback between Colombian and New Zealand FL Beginners: A Comparison and Lessons Learned (Retroalimentación virtual de pares entre aprendices principiantes de lengua de Colombia y Nueva Zelanda: una comparación y lecciones aprendidas)

    ERIC Educational Resources Information Center

    Tolosa, Constanza; Ordóñez, Claudia Lucía; Alfonso, Tania

    2015-01-01

    We report on an exploratory study comparing the performance as online tutors of two groups of beginner eleven-year-old students of English in Colombia and Spanish in New Zealand. The native speaker students of the foreign language the others were learning corrected paragraphs written by their peers. The feedback provided by each group of tutors…

  12. Exploring Elementary Students' Power and Solidarity Relations in an EFL Classroom (Exploración de las relaciones de poder y solidaridad entre estudiantes de primaria en la clase de inglés como lengua extranjera)

    ERIC Educational Resources Information Center

    Méndez, Tatiana; García, Andrea

    2012-01-01

    This article derives from a critical discourse analysis study that reports the characteristics of elementary school students' power and solidarity relations in English as a foreign language classroom in Bogotá, Colombia, while we were doing our teaching English as a foreign language practicum. The study was based on theories of power and…

  13. Como ayudar a su hijo durante los primeros anos de la adolescencia: Para los padres con ninos entre las edades de 10 a 14 anos (Helping Your Child through Early Adolescence: For Parents of Children from 10 through 14).

    ERIC Educational Resources Information Center

    Paulu, Nancy

    Recognizing that parents and families can greatly influence the development of their 10- through 14-year-olds, this Spanish-language booklet is part of a national effort to provide parents with the latest research and practical information to help them support their children both at home and in school. The booklet is organized in 13 sections…

  14. Adequation between environmental shifts and human speciations during the Plio-PleistoceneAdéquation entre changements environnementaux et spéciations humaines au Plio-Pléistocène

    NASA Astrophysics Data System (ADS)

    Zeitoun, Valery

    2000-01-01

    Several synthetic studies provide evidence of faunistic and floristic shifts as consequences of global climatic events around 2.5 and 1.8 Ma. Some authors are more confident in the role played by local tectonic events to explain such a change in terms of vicariance. It is possible that astronomic, tectonic and climatic variations are linked, as the lithosphere is a catalyst for biosphere more or less strong according to the period. The purpose of this paper is to confront independent environmental and anatomical data to try to understand the evolutionary process in hominids, with particular emphasis on species of the genus Homo in East Africa during the Plio-Pleistocene period. Thus the result of a cladistic analysis based on 35 Otus and 468 features of the calvaria is showing the onset of at least four species to describe the grade of Homo habilis, living in East Africa. The radiation is congruent with the contemporaneous environmental shifts around 2.5 Ma, as is also the case for bovids or cercopithecids. Some Homo erectus left Africa when another climatic pulse happened around 1.8 Ma.

  15. Relaciones hidrogeologicas y medioambientales entre el mar mediterraneo, El saladar y el acuifero de agua amarga (provincia de alicante). Incidencia de las explotaciones de las desaladoras de alicante I Y II Y medidas correctoras

    NASA Astrophysics Data System (ADS)

    Manteca, Ivan Alhama

    The Agua Amarga coastal aquifer, located in the south of Alicante province, has been subjected to successive anthropogenic actions: salt works activity (1925-1975) and water withdrawal to supply the Alicante I and II desalination plants (since 2003). These interventions have influenced the salinity and the flow regime. Due to the existence of a salt marsh of ecological interest linked to the aquifer, the 'Mancomunidad de los Canales del Taibilla' (agency responsible for the desalination plants) designed a piezometric network for monitoring piezometry and electrical conductivity (in operation since May 2008). Soil humidity and piezometrics levels have been recovered by means of a seawater pouring programme over the salt marsh (since December 2009),which represents the third anthropic intervention. In this memoria, we investigate the Agua Amarga coastal aquifer to develop a physical conceptual model. Firstly, the study area is characterized in relation to climatology, geology, geomorphology and hydrogeology, using published information, describing, in addition, the desalination plants catchment system. Next, based on hydrogeological studies prior to the start up of the desalination plants, the aquifer is characterized: type, lithology, hydraulic parameters, thickness, surface extension, etc. Water quantity relating to rainfall, water withdrawal and pourings over the salt marsh, have been integrated in conjunction with data from monthly piezometric campaigns. In adittion, in order to gain insight into the groundwater mixing processes, chemical and isotope analyses were carried out on meteoric water and groundwater samples taken at different locations. The results were used to elaborate a conceptual physical model and a water budget. As an extension tool to understand processes and assess aquifer management, a 3-D fluid-flow and solute-transport model is designed with SEAWAT. Also, the 2-D physical characterization of scenarios with seawater intrusion and salt flats is presented. Finally, after describing ecological values of the salt marsh, the effect of the seawater pouring programme on aquifer piezometry and salinity is studied, assessing the possibility of applying this pilot scheme to other scenarios.

  16. The Differences between Spoken and Written Grammar in English, in Comparison with Vietnamese (Las Diferencias entre la Gramática Oral y Escrita del Idioma Inglés en Comparación con el Idioma Vietnamita)

    ERIC Educational Resources Information Center

    Thanh, Nguyen Cao

    2015-01-01

    The fundamental point of this paper is to describe and evaluate some differences between spoken and written grammar in English, and compare some of the points with Vietnamese. This paper illustrates that spoken grammar is less rigid than written grammar. Moreover, it highlights the distinction between speaking and writing in terms of subordination…

  17. Vinculos Entre la Capacitacion de Docentes y el Desarrollo de Materiales Educativos Impresos--Anotaciones para Una Discusion (Links between In-service Teacher Training and the Development of Printed Educational Aids).

    ERIC Educational Resources Information Center

    Valle, Victor M.

    Textbooks and other printed materials will be ever present, in the foreseeable future, as major aids for teaching and learning processes. New textbooks imply new guidelines for teachers, and the ways to handle such guidelines demand teacher training. This paper explains some links between inservice teacher training programs and the development of…

  18. Parámetros astrofísicos fundamentales de 6 cúmulos de la Nube Mayor de Magallanes en el rango de transición entre 200 y 700 millones de años

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Bica, E.; Geisler, D.; Clariá, J. J.

    Complementing our recent Washington photometric studies on intermediate age and young Large Magellanic Cloud (LMC) clusters, we present in this work new results for 6 previously unstudied star clusters in the transition range 200-700 Myr. We study NGC 1836, NGC 1860 and NGC 1865, which are projected on the LMC bar; SL 444, also located in the central disc but outside the bar, and LW 224 and SL 548, both located in the outer disc. We derive ages and metallicities from extracted T1 versus C-T1 colour-magnitude diagrams (CMDs), using theoretical isochrones recently computed for the Washington system. For the metallicity determinations, these CMDs are particularly sensitive. We also estimate ages and metallicities of the surrounding fields of NGC 1860 and NGC 1865 by employing the δT1 index and theoretical isochrones.

  19. Solution analytique pour le transfert de masse entre puits en milieu poreux hétérogèneAnalytical solution for mass transfer between wells in heterogeneous porous media

    NASA Astrophysics Data System (ADS)

    Carlier, Jean-Philippe; Ackerer, Philippe

    2003-10-01

    The analytical solution developed by Dagan and Indelman (Water Resources Res. 35 (12) (1999) 3639-3647) for modelling the transport of a tracer in an infinite heterogeneous porous media in a dipole flow is extended by accounting for the presence of no flow finite boundaries. The results obtained are compared to those corresponding to the infinite domain, emphasizing the important influence of the boundaries on the elution at the pumping well and the effect of the medium's heterogeneity. The analytical results are then compared to experimental data and provide good matching. To cite this article: J.-P. Carlier, P. Ackerer, C. R. Mecanique 331 (2003).

  20. Highlighting the Impacts of North-South Research Collaboration among Canadian and Southern Higher Education Partners (Principaux impacts des collaborations de recherche Nord-Sud entre les partenaires des etablissements d'enseignement superieur du Canada et du Sud)

    ERIC Educational Resources Information Center

    Association of Universities and Colleges of Canada, 2006

    2006-01-01

    The Association of Universities and Colleges of Canada (AUCC) felt it was timely to create an academic forum in which university researchers have the opportunity to engage with their peers and relevant stakeholders and document the impacts of their North-South research collaboration in a peer-reviewed publication. The Association achieved this by…

  1. New Information Technologies in Schools: Teacher Training, Research and the Role of Universities. Illustrative Examples of Co-operative Projects between Universities and Schools = Exemples significatifs de projets de cooperation entres les universites et les ecoles.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France). Centre for Educational Research and Innovation.

    This guide contains examples of cooperative projects between universities and schools currently in existence in 22 countries in which the institutions of higher education are promoting or assisting with the implementation of new information technologies in elementary and/or secondary schools. Information given for each project includes the title

  2. O Imperio como Argumento: Um Contraponto entre Joaquim Nabuco e o Bispo D. Jose Mauricio da Rocha (The Empire as Argument: A Counterpoint between Joaquim Nabuco and the Bishop Dom Jose Mauricio da Rocha).

    ERIC Educational Resources Information Center

    Marson, Izabel Andrade

    1998-01-01

    Dialogs with the previous article establishing a comparative analysis between the political acceptance present in the reactionary speech of Dom Jose Mauricio da Rocha and in the monarchist words of Joaquim Nabuco. (PA)

  3. Pushing Too Little, Praising Too Much? Intercultural Misunderstandings between a Chinese Doctoral Student and a Dutch Supervisor (¿Empujando muy poco, felicitando demasiado? Malentendidos interculturales entre un estudiante de doctorado Chino y un supervisor Holandés)

    ERIC Educational Resources Information Center

    Hu, Yanjuan; van Veen, Klaas; Corda, Alessandra

    2016-01-01

    To understand the challenges and their causes in interactions between Western supervisors and international doctoral students, we conducted a self-study of our experiences as a Chinese international student and her Dutch supervisor during her doctoral research project. We found the supervisor and the student to differ in their expectations of the…

  4. Vinculacion Entre La Educacion Y El Mundo Del Trabajo: Informe Final. (Coloquio Regional Caracas, Venezuela, Septiembre 2-6, 1985) = The Linkage Between Education and Employment: Final Report of the Regional Colloquium (Caracas, Venezuela, September 2-6, 1985).

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.

    At this regional colloquium 13 papers were presented concerning the relationship between education and employment. Themes addressed were: (1) the transformation of the workplace by technology and science; (2) the future of the disadvantaged population as a consequence of the technological revolution; and (3) the resulting changes in the education…

  5. Relations entre production organique et apports terrigènes dans les sédiments fluviatiles holocènes : observations et conclusions hétérodoxes

    NASA Astrophysics Data System (ADS)

    Macaire, Jean-Jacques; Di-Giovanni, Christian; Hinschberger, Florent

    2005-06-01

    Accumulation of organic matter in fens of fluvial valleys is often related to a low terrigenous matter delivery and to palaeoenvironmental conditions inducing low mechanical erosion. These assumptions come from the interpretation of contents in organic (MO) and mineral (MM) matters in sediments, expressed in percents, and then exactly anticorrelated. Calculation of mass accumulation rates of MO (Ta_MO) and MM (Ta_MM), expressed in g m -2 yr -1, shows that Ta_MO and Ta_MM generally are not anticorrelated and that high values of Ta_MO and Ta_MM could appear simultaneously. That expression of MO and MM accumulation makes it possible to precise the climatic and human impact on sedimentation. To cite this article: J.-J. Macaire et al., C. R. Geoscience 337 (2005).

  6. Relation entre évolution de la matière organique et caractéristiques géostructurales : exemple du bassin yprésien en Tunisie centro-septentrionale

    NASA Astrophysics Data System (ADS)

    Arfaoui, Adel; Montacer, Mabrouk

    2006-08-01

    The geochemical analysis of the organic-rich facies from the Ypresian basin in central-northern Tunisia shows that the organic matter is marine originated (type II) and displays a low thermal maturity level in outcropping samples. This study proves that the distribution, conservation and, therefore, the composition of the organic matter have been controlled by the dynamic of the Ypresian basin. The Ypresian period corresponds to an anoxic event, which led to the accumulation and preservation of good quantities of organic matter derived from a high primary production. To cite this article: A. Arfaoui, M. Montacer, C. R. Geoscience 338 (2006).

  7. Positive Prevention: Successful Approaches To Preventing Youthful Drug and Alcohol Use [and] La Prevencion Positiva: Metodos que han tenido exito en la prevencion del uso de drogas y alcohol entre la juventud.

    ERIC Educational Resources Information Center

    American Association of School Administrators, Arlington, VA.

    The United States has the highest rate of youthful drug abuse of any industrialized country in the world. There is a growing awareness that drug and alcohol use are closely connected to other problems such as teenage suicide, adolescent pregnancy, traffic fatalities, juvenile delinquency, poor school performance, runaways, and dropouts. Youthful…

  8. Vinculacion Entre La Educacion Y El Mundo Del Trabajo: Informe Final. (Coloquio Regional Caracas, Venezuela, Septiembre 2-6, 1985) = The Linkage Between Education and Employment: Final Report of the Regional Colloquium (Caracas, Venezuela, September 2-6, 1985).

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.

    At this regional colloquium 13 papers were presented concerning the relationship between education and employment. Themes addressed were: (1) the transformation of the workplace by technology and science; (2) the future of the disadvantaged population as a consequence of the technological revolution; and (3) the resulting changes in the education

  9. Teacher Collaboration Praxis: Conflicts, Borders, and Ideologies from a Micropolitical Perspective (La práctica colaborativa entre docentes: conflictos, fronteras e ideologías desde una perspectiva micropolítica)

    ERIC Educational Resources Information Center

    Keranen, Nancy; Encinas Prudencio, Fátima

    2014-01-01

    This paper looks at a feature of teacher collaboration within Achinstein's (2002) micropolitics of collaboration but from an intrapersonal perspective. Results discussed feature issues of conflict, borders, and ideologies within each participating teacher rather than between teachers. Unresolved or unacknowledged intrapersonal conflict might lead…

  10. Etude theorique et experimentale de la correlation entre la resistance aux chocs thermiques et aux chocs mecaniques des materiaux refractaires utilises dans les fours de traitement de l'aluminium

    NASA Astrophysics Data System (ADS)

    Sebbani, Mohamed Jamal Eddine

    2001-07-01

    This work is a theoretical and experimental study of the correlation between the resistance to thermal shock and mechanical shock of refractory materials. The study of thermal shock showed that the Bahr and Hasselman approaches are alike and that they can be combined into a single, more general approach. This generalisation allowed the division of the theoretical models into two groups: the Hasselman model and the Harmuth model. However, neither of these approaches can predict the behaviour of all refractory materials submitted to thermal shock. Therefore, the generalisation of the Hasselman approach is more appropriate for more dense materials while the Hartmuth approach is more appropriate for less dense materials. The influence of porosity on the energy of rupture helped to explain the behaviour of the less dense material. The absence of generalisation in this case allows those parameters that could be correlated with thermal shock resistance to be dependent on the type of refractory. The study of mechanical shock provided a better understanding of this mechanism. The work performed showed, theoretically and experimentally, that the resistance of the refractory materials could be correlated with the parameter s20 Egwof n-22 . This new parameter helped to explain the statistical correlation between the resistance to mechanical impact and the soxRst parameter established in earlier work. The sintering influence, which makes the refractories more resistant to this type of demand, notably by reducing the "n" coefficient, was shown. This part of the study allowed the establishment of equivalence between thermal fatigue and fatigue by mechanical impact. An evaluation of the correlation between the two mechanisms demonstrated, theoretically and experimentally, that the mechanical and thermal demands could only be exceptionally correlated. In the case of thermal shock, which are imposed deformation demands, it is the shorter cracks which are the most dangerous. However, in the case of mechanical shock, which is constraint imposed, it is the longer cracks that are the most harmful. (Abstract shortened by UMI.)

  11. [The EMECAM project: a discussion of the results in the participating cities. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica y la Mortalidad].

    PubMed

    Ballester Díez, F; Sáez Zafra, M; Pérez-Hoyos, S; Daponte Codina, A; Bellido Blasco, J B; Cañada Martínez, A; Abad Díez, J M; Pérez Boíllos, M J; Alonso Fustel, M E; Taracido Trunk, M; Aguinaga Ontoso, I; Guillén Pérez, J J; Ordóñez Iriarte, J M; Saurina Canals, C; Tenías Burillo, J M

    1999-01-01

    This article draws a comparison and provides a discussion of the findings resulting from the local analyses of the 14 cities participating in the EMECAM Project. An analysis is made of the time series related to mortality, pollutants (particles in suspension, SO2, NO2, O3 and CO), temperature and other factors taken from records of public institutions. By using Poisson autoregressive regression, an estimate has been made of the short-term relationship between the number of deaths and the air pollution indicators in each one of the following cities: Barcelona, metropolitan area of Bilbao, Cartagena, Castellón, Gijón, Huelva, Madrid, Pamplona, Seville, Oviedo, Valencia, Vigo, Vitoria and Saragossa. The findings reveal the air pollution figures in our country to be similar to those of other European cities. The levels of the different pollutants point toward road traffic as being the main source of most of this pollution. A relationship has been found between the mortality and different pollutants in most cities, although the results are not homogeneous among the cities and show variability in the different causes under study. In some cities, especially in those having smaller populations, there have been no findings providing any evidence of a relationship, or the findings themselves are not highly consistent. The meta-analysis will provide estimates for all of the cities as a whole and will allow the possibility of making a more clear-cut assessment of the time lag impact of air pollution on the mortality. Worthy of special mention is the participation in this project of public health officers as actively involved researchers. PMID:10410614

  12. Repertoire de didacticiels de francais langue seconde ou etrangere publies entre 1980 et 1988 (List of Courseware for French as a Second or Foreign Language Published between 1980 and 1988). Publication K-11.

    ERIC Educational Resources Information Center

    H.-Lemonnier, France; And Others

    A listing of 97 items of courseware includes programs in seven categories, pertaining to: (1) vocabulary; (2) grammar; (3) verb conjugation; (4) syntax and/or morphosyntax; (5) reading and/or writing; (6) oral language; and (7) other areas of French second language instruction. Each citation includes the title, program type (e.g. drill, game),…

  13. Como ayudar a su hijo a tener exito en la escuela, con actividades para ninos entre las edades de 5 a 11 anos (Helping Your Child Succeed in School, with Activities for Children Ages 5 through 11).

    ERIC Educational Resources Information Center

    Paulu, Nancy

    At the heart of the No Child Left Behind Act of 2001 is a promise to raise standards for all children and to help all children meet those standards. This Spanish-language booklet provides information that parents can use to help their child succeed in school. Following an introduction, the second section of the booklet, "The Basics," offers…

  14. Peer Interaction: A Social Perspective towards the Development of Foreign Language Learning (Interacción entre pares: una perspectiva social hacia el desarrollo del aprendizaje en una lengua extranjera)

    ERIC Educational Resources Information Center

    Gómez Lobatón, July Carolina

    2011-01-01

    This pedagogical innovation aims at discovering new ways of interaction that go beyond the unidirectional relationship that is presented in the classrooms most of the times. The innovation considers peers to be active agents in the construction of knowledge and proposes new ways to arrange groups in the classroom so that the arrangement can…

  15. La Desercion Escolar en los Niveles de Sexto y Noveno Grado: Una Comparacion Entre Zonas Rurales y Urbanas. Boletin 219 (The Educational Desertion in the 6th and 9th Grades: A Comparison Between Rural and Urban Zones. Bulletin 219).

    ERIC Educational Resources Information Center

    Lopez, Maria I. Hernandez; And Others

    In 1962 and again in 1965, a group of sixth and ninth grade students in selected schools in four Puerto Rican communities were interviewed to investigate the factors influencing students' decision to withdraw from school before completing twelfth grade and to identify some characteristics of dropouts. Of 616 students interviewed in 1962, 20.9% of…

  16. CONTAMINACIÓN AMBIENTAL, VARIABILIDAD CLIMÁTICA Y CAMBIO CLIMÁTICO: UNA REVISIÓN DEL IMPACTO EN LA SALUD DE LA POBLACIÓN PERUANA

    PubMed Central

    Gonzales, Gustavo F.; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

    2015-01-01

    RESUMEN El presente artículo es una revisión sobre la contaminación del agua, el aire y el efecto del cambio climático en la salud de la población peruana. Uno de los principales contaminantes del aire es el material particulado menor de 2,5 μ (PM 2,5), en la ciudad de Lima, anualmente 2300 muertes prematuras son atribuibles a este contaminante. Otro problema es la contaminación del aire domiciliario por el uso de cocinas con combustible de biomasa, donde la exposición excesiva a PM 2,5 dentro de las casas es responsable de aproximadamente 3000 muertes prematuras anuales entre adultos, con otro número desconocido de muertes entre niños debido a infecciones respiratorias. La contaminación del agua tiene como principales causas los desagües vertidos directamente a los ríos, minerales (arsénico) de varias fuentes, y fallas de las plantas de tratamiento. En el Perú, el cambio climático puede impactar en la frecuencia y severidad del fenómeno de El Niño oscilación del sur (ENSO) que se ha asociado con un incremento en los casos de enfermedades como cólera, malaria y dengue. El cambio climático incrementa la temperatura y puede extender las áreas afectadas por enfermedades transmitidas por vectores, además de tener efecto en la disponibilidad del agua y en la contaminación del aire. En conclusión, el Perú, pasa por una transición de factores de riesgo ambientales, donde coexisten riesgos tradicionales y modernos, y persisten los problemas infecciosos y crónicos, algunos de los cuales se asocian con problemas de contaminación de agua y de aire. PMID:25418656

  17. Farmyard Manure and Fertilizer Effects on Seed Potato (Solanum tuberosum L.) Yield in Green House Production

    NASA Astrophysics Data System (ADS)

    László, M.

    2009-04-01

    Nowadays is widely well know that the potato is an important vegetable crop at Brazíl. It is grown on about 173.000 ha, with total yield of 2.6 million tons year-1. The average yield is 15 t ha-1. This level is very low because degeneration of crop is rapid under high temperature and high viruses pressure. Therefore seed potato propagation and production is principal on consumption potato production. This is why we found it necessary to develop it. The latossolo vermelho soil-farmyard manure- burnt rice straw-fertilizer 4N:14P:8K greenhouse pot trial was set up at the National Vegetable Crops Research Center, Brasília-DF, Brazíl in 1990. The methods of the experiments were soil x farmyard manure x burnt rice straw, soil x 4N:14P:8K fertilizer and soil x farmyard manure x burnt rice straw x 4N:14P:8K fertilizer on randomized block design in total 29 combination of treatments in 5, 5 and 3 repetitions with in a total parcel of 116. According to chemical analysis of the a., soil, b., farmyard manure and c., burnt rice straw the agrochemistry parameters were as follows (estimated datas): a., latossolo vermelho soil: CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1, b., farmyard manure: N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., burnt rice straw: N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. The experimental datas were estimated by analysis of variance, ANOVA and MANOVA. The main conclusions were as follows: 1. Mixture of 80% latossolo vermelho, 10% burnt rice straw and 10% farmyard manure were shown best performance on seed potato productivity. The piece of tubers with a 0-20 mm (consumption seeds) was increased by 77%. 2. Total seed potato number was reached maximum at 10.8 g pot-1 4N:14P:8K fertilizer regarding to average of treatments with a 33%. 3. Dry biomassa production plant-1 was decreased by high dose of 4N:14P:8K fertilizer (18.0 g pot-1) with a hard effect (57%). Our results are shown that it was possible developing of the seed potato production under tropical greenhouse conditions by optimalised soil-organic matter-fertilizer system. This datas should be as indicators to sustainable field potato advisory systems. Keywords: potato (Solanum tuberosum L.), greenhouse, latossolo vermelho soil, farmyard manure, burnt rice straw, 4N:14P:8K fertilizer, sustainability, yield Introducáo: Importância e situação actual em produção da batata no Brazíl A batata é atualmente uma das hortaliças de maior importância no Brasíl (Márton 2000a., 2000b.) com um cultivo annual médio de 173.000 ha e uma produção de 2600000 t. A produtividade médio nacional é de 15 t ha-1, muito baixa se considerar que é possivel a obtenção de rendimentos acima de 40 t ha-1. Observa- se também, que existe variação no produtividade entre regiões e estados. E importante como fonte de alimento pelo seu alto valor nutricional a quantidade produzida muito superior por unidade de área a tempo, se comparada com diversas outras culturas (László 2000b., 2000c.). Os estados que tradicionalmente produzem batata em maior ou menor escala são indicados em seguente: Pernambuco, Ceará, Sergipe, Goiás, Mato Grosso, Mato Grosso do Sul, Rondonia e Acre. Os plantios predominantes são o das águas e das secas, sendo o de inverno bem menos expressivo, pois poucas áreas permitem o seu cultivo, na maioria dos casos necessitando- se de irrigação. Considerando as três épocas de plantio e diferentes condições climaticas brasileiras, podemos definir de um modo geral o plantio de batata no Brasíl da seguinte maneira: Nordeste e Centro- Oeste- plantio de inverno, Sudeste- plantio das águas, secas e inverno, Sul- plantio das aguas, secas e inverno. Sendo este último em áreas muito limitadas. Dentre as hortaliças a batata é uma das culturas mais estudadas actualmente. Os principais problemas que afetam a cultura da batata podem ser de ordem agronómica, economica e comercial. Como exemplos destes podem ser citados: o uso racional de matérias orgânicos, esterco de curral e inorgânico fertilizantes. Efeito de materias orgnicânicos e N, P, K elementos minerais para produção da batata As necessidades em N, P, e K elementos minerais da batata são superidas pela aplicação apropriada de matérias orgânicos, esterco de currals, fertilizantes ao solo, combinada com a ambiente (Márton 2001a., 2001b.), época adequada e posição ideal de aplicá- lo. Efeito da materias orgânicos O suprimento de N á batateira provém principalmente da matéria orgânica do solo e do fertilizante aplicado (László 2000a., Márton et all. 2000.). Embora não seja muito praticado no Brasíl, a incorporação de esterco ao solo é fator de aumento da produção de tuberculos. Este resultado favorável poderia ser atribuído ao melhoramento da estrutura do solo, á maior retenção de água pelo e mesmo favorecendo o melhor desenvolvimento do sistema radicular da planta. A batata pode ser cultivada em todo tipo de solo desde que tenha boa drenagem e seja bem estruturado. Isto é tem que ser bem aerado e permitir o bom desenvolvimento dos órgãos subterráneos da batateira. Sem de matéria orgânicos e esterco de curral a tendencia de determinados solos formar crosta, oferecendo uma alta resisténcia mecánica á emergéncia das plantas, pode ser um determinante de stands desuniformes. A cause primaria da formação de crostas é a destruição dos agregados do solo pela excessiva manipulação mecánica resultando em aeração reduzida e aumento da densidade e coesão das particulas do solo. O encrostamento do solo pode ser reduzido através com matérias orgânicos. De maneira geral, a produção de tuberculos em solo de baixa potencialidade (aqueles em que a penetração das raizes é dificultada pela compactação, textura argilosa ou com camadas no solo) será menor do que nagueles com alta potencialidade (boa textura e adequada retenção de agua). Efeito do nitrogênio No Brazíl em todas regiões onde se cultiva batata é raro encontrar solos com elevado teor de nitrogênio e que não precisam de quantidades desta elemento. É o elemento que governa o padrão de desenvolvimento da planta, estimulando principalmente o crescimento da parte aérea (Kádár et all. 2000., László 2000.). Para se obter rendimento de tubérculos é necessário um rápido e curto periodo de desenvolvimento da parte aérea e uma fase de acúmulo maior possível. Para tanto, devem ser evitadas doses muito altas de nitrogênio e, principalmente, se aplicadas tardiamente, pois haverá demasiado desenvolvimento de folhas que demorarão mais a finalizar seu crescimento e maturação. Isto implicará na redução do periodo de intenso desenvolvimento dos tubérculos e armazenagem do amido, resultando em menor produção. Há risco para a saúde na ingestão de alimentos com altos teores de nitrato e nitrito, havendo preocupação com o efeito de doses mais altas de nitrogênio sobre os teores dos mesmos nos tuberculos. Embora haja diferenças entre cultivares, localidades e períodos de armazenamento, há estudos mostrando que a fertilização com até 150 kg ha-1 de nitrogênio não foi suficiente para propiciar niveis preocupantes de nitrato nos tuberculos colhidos. Efeito do fósforo A grande maioria dos solos brasileiros cultivados com batata apresentam limitações ao bom desenvolvimento e produção da cultura em função dos baixos níveis de fósforo. Isto significa que aumentos de produção quase sempre ocorrem quando o solo recebe adubação fosfatada (László 2001a.). Estes aumentos são mais marcantes em solos nunca antes adubados ou com baixo teor de fósforo. Nestes, dificilmente alcanca- se a produção máxima com níveis reduzidos de fósforo. Não seria exagerado supor níveis de 600 a 800 kg ha-1 de P2O5, como sendo aqueles que iriam proporcionar produção máximas, principalmente em solos mais ácidos e pobres em matéria orgânico. A adubação fosfatada é muito importante no crescimento inicial da planta e, além de aumentar a produção de tuberculos em peso e números, aumenta também a quantidade e qualidade do amido neles contidos e reduz perdas durante o armazenamento dos mesmos. A quantidade de fósforo a aplicar dependerá da análise do solo considerando- se principalmente o nível de P existente e a textura do solo. Solos de textura média e arenosa necessitam maior conteúdo de fósforo do que os de textura argilosa para serem considerandos solos de baixo, médio ou alto teor de fósfato. Efeito da potássica Embora seja o elemento mais absorbido pela batateira, nem sempre há resposta positiva da aduba potássica sobre o rendimento da cultura. Provavelmente isto esteja relacionado com níveis elevados deste elemento no solo (Kurnik et all. 2001.). Entretanto, em solos com médios e baixos teores de potássio, aumentos significativos são conseguidos. Por isto, as recomendações de adubação com potássio, nas diversas regiões do mundo, variam de 50-300 kg ha-1 de K2O. Resultados de trabalhos em brasiléiros têm demonstrado que a aduba potássica pode ser substituída pela aplicação de 150 m3 ha-1 de vinhaça de cana de açúcar. Ao elevar- se a dose de fertilização potássica deverá haver precaução para que a adubação magnesiana seja suficiente. O K além de aumentar a produção, em solos deficientes, aumenta também o tamanho dos tubérculos produzidos, e a proporção de tubérculos grandes. Deficiência no suprimento de potássio á planta pode acarretar produção de tubérculos com elevada susceptibilidade aos danos mecánicos pós-colheita. Os tubérculos injuriados enegrecem facilmente e este enegrecimento é inversamente proporcional á quantidade de potássio nos tuberculos. Ademais, quando fritos dão origem a um produto escuro, de baixa valor comercial. Manejo de adubação Diversos fatores como potencial de produção do solo, modo de aplicação do fertilizante dentre outro fatores afetam a resposta da batateira á aplicação de fertilizantes (Refschneider 1987.). Depreende- se pois que no estabelecimento de um nivel ideal de fertilização as variáveis planta, solo e condições climaticas devem ser visualizadas como um sistema pouco provável de ser homogeneo mesmo em nivel de fazenda. Como tal, generalizações a respeito de doses ou niveis de fertlização são difíceis de serem feitas, recomendações exigem julgamento hábil por parte do fazendeiro ou do tecnico responsavel pela cultura (Márton 2001a., 2001b.). Este julgamento será mais preciso conhecendo- se pontos que serão rápidamente discutidos a seguir. A taxa de absorção de nutrientes é governada pela concentração externa ou suprimento de nutrientes pelo solo e a demanda do nutriente criada pelo desenvolvimento e funcinamento normal dos diversos órgãos das plantas. O nivel de nutrientes na solução do solo deve ser suficiamente alto para que suas taxas de absorção não sejam limitantes ao crescimento. Por outro lado, não deve ser demasiado para causar excessiva absorção de outros nutrientes. Forte associação existe entre a absorção de nutrientes e o desenvolvimento da planta. De maneira geral, a fase de rapido desenvolvimento da cultura é acompanhada por um grande aumento na absorção de nutrientes com a taxa de absorção declinado quando a taxa de crescimento diminuiu. Normalmente todos os fertilizantes potássicos e fosfatados são adicionados ao solo na época do plantio. O nitrogênio normalmente é parcelado. Cerca de 2 por 3 do nível recomendado é colocado no sulco de plantio e o restante adicionado por ocasião da amontoa. É uma prática tradicinal e com pouco suporte experimental no condiõces brasileiras. Espera -se que a aplicação parcelada do nitrogênio e mesmo do potássio possem ser benéficas quando houver chuva excessiva ou irrigações mal executadas principalmente em solos mais arenosos onde poderá ocorrer a lixiviacão dos mesmos (Márton 2001a., 2001b.). O parcelamento poderá também ser benéfico quando elevados níveis de fertilizantes porém recomendandos e a aplicação por feita nos sulcos de plantio, pois evitar-se ia assim, elevada concentração salina em torno dos tubérculos plantados, embora a aplicação á lanco, em toda área, possa ser opção vantajosa. Quantidades corretas de fertilizantes, posição ideal e época certa de aplicação, combinadas adequadamente, definem o programa de adubação da batata. Esse programa é variável de acordo com o solo, a batata e condisões ambientais (Márton 2001a.). A dose de um elemento a ser aplicada em batata, é função da quantidade desse elemento suprida pelo solo e da percentagem de recuperação do elemento adicionado ao solo como fertilizante. Resultados experimentais comparando a aplicação de fertilizante á lanco ou localizado mostram respostas variadas sobre a produção. E possivel encontrar resultados iguais em ambos os métodos, de supremacia da aplicação á lanco ou da aplicação localizada (Kurnik et all. 2001.). Parece que baixas quantidades de fertilizantes são mais eficiemente utilizadas quando aplicação nos sulcos de plantios. Entretanto o potancial de produção pode ser aumentando com alta ou mesmo moderada quantidade de fertilizantes aplicados á lanço. A recomendação geral de colocar o adubo no sulco de plantio da batata merece ser questionada. É uma recomendação válida ao entender- se que a batata responde bastante á aplicação de fósforo, que os solos brasileiros tem alta capacidade de absorção de fósforo e que haverá maior proliferação de raízes na área fertilizada. Uma indagação aparece: um solo com baxa disponibilidade de fósforo fora da zona fertilizada permitiria o desenvolvimento ótimo da planta. Algumas evidéncias mostram, para outras espécies, que grande parte do sistema radicular, deve estar exposta ao fósforo para suprir as necessidades das plantas. Ademais, há um determinado valor de concentração de fósforo, na solução do solo, acima da qual a taxa de absorção não é aumentada. Essas considerações suscitam a possibilidade de questionar se a aplicação de fósforo em sulcos seria a forma mais eficiente de usá-lo quando se pretende alcancar elevadas produções. Deve-se lembrar entretanto, que solos tropicais, ainda com baixos teores fósforo e alta capacidade de adsorção, seria necessária dose muito elevada de P, quando aplicada á lanço, em todo o terreno. Se a aplicação localizada do fósforo pode, em parte, ser explicada, a do nitrogênio e potássio não são facilmente justificadas sob o aspecto de eficiéncia de utilização. Pelo contrário, ela pode ser questionada, principalmente pelas suas caracteristicas de difusão, pelo efeito que altas concentração de amónio e cloreto podem ter sobre a pressão osmotica da solução do solo junto aos tubérculos plantados, pelo efeito negativo do cloreto sobre a absorção de fósforo e também sobre a capacidade produtiva das plantas. Portanto, existe a possibilidade de ocorrer toxidez de amónio e de cloreto ao se aplicar doses altas dos fertilizantes nos sulcos de plantios. Isto pode determinar uma menor eficiéncia no uso dos fertilizantes. Materiais e Metodos: Nos desenvolverémos os três experimentos (i.e.: 1., 2., 3.) para aumentár-se do produção e produtividade da batata (Solanum tuberosum L.) semente pré- básica no casa de vegetação com diferentes doságens do latossolo vermelho novo, do esterco de curral e do adubo fórmula 4N:14P:8K no Empresa Brasileira de Pesquisa Agropecuaria- Centro Nacional de Pesquisas de Hortaliças, da Brazília-DF no 1990. Caracteristicas agroquímicas do solo em faixa arado (dados estimados), e conteudos N, P2O5, K2O do esterco de curral e palha de arroz queimado (dados estimados): a., caracteristicas agroquímicas do solo latossolo vermelho (solo novo: nunca foi usado para produção da batata semente): CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1 com abastecer fraco destes elementos, b., conteudos N, P2O5, K2O do esterco de curral (qualidade médio): N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., conteudos N, P2O5, K2O do palha de arroz queimado (palha de arroz foi queimado em um especial forno): N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. Nestas provas usarémos para controle a *mistura padrão. O este tratamento é a composição usual neste programa i.e.: 150 l de solo novo, 50 l de palha de arroz queimado, 50 l de esterco de curral, 350 gramas de cal e 300 gramas de adubo da fórmula 4N:14P:8K. Experimento 1. Efeito de diferentes misturas para produção da batata semente pré- básica em casa de vegetação O experimento foi instalado considerando-se sete misturas de substrato (latossolo vermelho novo, esterco de curral, palha de arroz queimado) em 3000 cm3 volume de capacidade de vasos preto com cinco repetições, no delineamento experimental de blocos ao acaso, na mésas experimentais em caso de vegetação. A cultivar foi a Achat, com plãntulas provenientes de cultura de tecidos. A data de plantio foi 18.04.1990. Plantarémos em cada vaso 3-3 "in vitro" plantulas com raiz embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado com ventilação automatizado. Temperatura médio foi 22 0C e humidade médio foi 68% durante de experimento. A data de colheta foi 04.07.1990. As pesagens foram feitos como peso fresco. Os resultados foram submetidos a analise de variáncia, ANOVA. As misturas do substrato utilizadas foram como a seguir no Tabela 1. Experimento 2. Efeito de adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação O experimento foi instalado considerando-se 9 dosagens de adubo da fórmula 4N:14P:8K com latossolo vermelho novo em 3000 cm3 volume de capacidade de vasos preto com cinco repetições, no delineamento experimental de blocos ao acaso na mésas experimentais em casa de vegetação. O adubo foi posicionando no solo de 4 cm abaixo de superficie do solo. A cultivar foi a Achat, com plãntulas provenientes de cultura de tecidos. A data de plantio foi 18.04.1990. Plantarémos em cada vaso 3-3 "in vitro" plantulas com raiz embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado com ventilação automatizado. Temperatura médio foi 22 0C e humidade médio foi 68% durante de experimento. A data de colheta foi 04.07.1990. As pesagens foram feitos como peso fresco. Os resultados foram submetidos a analise de variáncia, ANOVA. As doságens de adubo foram como a seguir no Tabela 2. Experimento 3. Efeito de latossolo vermelho novo, palha de arroz queimado e adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Para pesquisar estes efeitos o experimento tipo de (2 x 6) foi instalado considerando-se as combinações entre duas misturas (i.e.: 1., 2.) e seis doságens de adubo complexo 4N:14P:8K, com três repetições, no delineamento experimental de bloco ao acaso, sendo 1 vaso (3000 cm3 volume de capacidade de vasos preto) por parcela na mésas experimentais em casa de vegetação. O adubo foi posicionando no solo de 4 cm abaixo de superficie do solo. A cultivar utilizada foi Baraka e o tamanho de tuberculos foi com 0-20 mm. A data de plantio foi 25.09.1990. Plantarémos em cada vaso 3-3 tuberculos com embaixo de 4cm de superficie da mistura no vasos. Irrigarémos com 12 mm quantidade da augua 2 vezes por semana. Para produção aplicarémos sistema de proteção de plantas como usados no Brasíl. Ambiente foi controlado ventilação automatizado. Temperatura médio foi 21 0C é humidade médio foi 66% durante de experimento. A data de colheta foi 14.12.1990. As pesagens foram feitos como peso fresco e matéria seca. Os resultados foram submetidos a analise de variáncia, MANOVA. Os manejos foram como a seguir no Tabela 3. Resultados e Discuscáo Experimento 1. Efeito de diferentes misturas para produção da batata semente pré- básica em casa de vegetação O tratamento 3. i.e.: mistura de 80% latossolo vermelho novo, 10% palha de arroz queimado e 10% esterco de curral, apresentou os maiores valores para numero de tuberculos com 0-20 mm (tamanho de comercial), peso de tuberculos com 0-20 mm e peso total de tuberculos por vaso. Porém, não houve diferencas significativas para o numero tuberculos comerciais, i.e.: com 0-20 mm, para os tratamentos 2., 3., 4., e 5. Portanto, a mistura poderá ter uma composição entre 60 a 90% de latossolo vermelho novo, 6 a 24% de palha de arroz queimado e de 4 a 16% de esterco de curral. Não houve diferenca significativa entre a mistura padrão utilizada e as misturas incluidas nos extremos indicados anteriormente. Porém, a mistura padrão recebeu adubação quimica de 4N:14P:8K (3.6 grama vaso-1) e calcário na dosagem de 4.2 grama vaso-1, o que não aconteceu com as parcelas das misturas em analise. Experimento 2. Efeito de adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Há um efeito crescente das dóses de 4N:14P:8K nos caracteres observados. Porém, a maior dóse não chegou a ultrapassar a mistura padrão. Experimento 3. Efeito de latossolo vermelho novo, palha de arroz queimado e adubo 4N:14P:8K para produção da batata semente pré- básica em casa de vegetação Efeitos de misturas As duas misturas (i.e.: 1 e 2) deram resultados significativos mais alto que a mistura padrão, em média 54 %. Entre as misturas 1 e 2, foi melhor a 2. (80% latossolo vermelho novo, 10% palha de arroz queimado, 10% esterco de curral). Examinando-se 15 fatores, entre 11 casos afirmou-se a mistura como para melhor que a mistura 1. (70% latossolo vermelho novo, 20% palha de arroz queimado, 10% esterco de curral). Em caso de número de tuberculos 0-20 mm com a mistura 2. foi possivel aumentar geralmente os números de tuberculos em 77% que a mistura padrão. Efeitos de adubação 1. Área da folhas por planta entre manejo foi melhor de modo significativo a doságem de 3.6 grama vaso-1 adubo complexo (3103 cm2 plantas-1). 2. Peso fresco da folhas e de hastes por plantas as tendencias foram parecidos com o da área de folhas. 3. Peso fresco de raizis por planta até 7.2 grama vaso-1 diminuiu depois aumentou. 4. Peso fresco total de tuberculos por planta as crescentes doságens de um modo forte diminuiram a produção de tuberculos de 0 e 18.0 grama vaso-1 em 160% em os dois caso da mistura. 5. Peso de fitomassa fresco por planta foi melhor a 3.6 g vaso-1 (239 grama planta-1 em médio da dois mistura), depois os dados diminuirám. 6. Produção de biomassa fresco por planta a maxima produção (188 grama planta-1) foi obtida com 3.6 grama vaso-1. Deste ponto de modo forte caiu a produção. 7. Peso da matéria seca de folhas, hastes e raizis por planta somente em caso de mistura padrão o resultado foi significativo em relação aos outros tratamentos. 8. Péso da matéria seca de tuberculos total por planta modo significativo diminuiu a produção (0 e 18.0 grama vaso-1 = 360%) em médio da duas misturas. 9. Biomassa produção de materia seca por planta modo significativo diminuiu para efeito de alta dosagens de adubo complexo (0 e 18.0 grama vaso-1 = 158%) em médio da duas misturas. 10. Peso fresco de tuberculos com 0-20 mm as crescentes dosagens de 0 e 18.0 grama vaso-1 diminuiram a produção em 213% em médio da duas misturas. 11. Peso fresco de tuberculos com 20 mm-1 as crescentes dosagens de 0 e 18.0 grama vaso-1 diminuiram a produção assima de 250% em médio da duas misturas. 12. Numero de tuberculos 0-20 mm e 20 mm- por planta com os manejos de 0 e 18.0 grama vaso-1 foi possível aumentar em media 200% sobre a mistura padrão. Os manejo de 18.0 grama de adubo vaso-1 já causaram importante diminuição em relação caso a absoluto controle. 13. Numero total de tuberculos por planta entre manejos foi melhor a dosagem de 7.2 grama vaso-1 adubo complexo 4N:14P:8K comparando da mistura padrão. Nos verificamos-se que a mistura padrão sempre deu menor rasultados do que as outras misturas (i.e.: 1 e 2). Entre as misturas 1 e 2 a melhor foi a número 2. (80% latossolo vermelho novo, 10% palha de arroz queimado, 10% esterco de curral). Com esta mistura e com relação a mistura padrão, foi possível aumentar o número de tuberculos 0-20 mm com 77%. No caso do adubação, verificamos que grande quantidades de adubo acima de 7.2 grama vaso-1, de modo rigoroso diminuiu a produção de batata-semente pré- básica. Este fato deve ser considerado para a eleição das dosagens de adubos. Deve-se indicar o caso de número de tuberculos acima 20 mm-, onde em relação mistura padrão foi possivel aumentar em média 73% os resultados. Reconhecimento: Esta pesquisa foi apoio da Empresa Brasileira de Pesquisa Agropecuaria- Centro Nacional de Pesquisas de Hortaliças, Brasília-DF e Centro Pesquisa de Solo e Agroquímica do Academia Húngara de Ciências, Budapest References Kádár I-Márton L.-Horváth S. 2000. Mineral fertilisation of potato (Solanum tuberosum L.) on calcareous chernozem soil. Plant Production. 49: 291-306. Kurnik E.-Németh T.-Márton L.-Radimszki L. 2001. Effects of a new environment friendly deep fertilization system on a limy chernozem soil parameters. Agrochemistry and Soil Science. Budapest. In press László M. 2000. Nutrition of potato (Solanum tuberosum L.) on Hungary on a chernozem soil. Acta Agronomica Óváriensis. 42: 81-93. László M. 2001a. Climate change and N, P, K, Mg fertilization effects on potato (Solanum tuberosum L.) yield and quality. EAPR. Hamburg. In press László M. 2001b. Year and fertilization effect analysis in long field term experiments. XLIII. Georgikon Days. University of Veszprém. Keszthely László M.-Imre K.-Jose E.M. 2000a. Effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH. on soil fertility and soil conservation in Hungary. Acta Agronomica Óváriensis. 42: 99-106. László M.-Silva J.C.-Jose A.B. 2000b. Ecological friendly dragée technics on different crops and vegetables seeds. Acta Agronomica Óváriensis. 42: 107-111. László M.-Silva J.B.C.-Jose A.B. 2000c. Ecological friendly dragée technics to sustainable precision agriculture. Fertilization in the Third Millenium. CASISCF. Beijing Márton L. 2000a. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Dissertation. University of Veszprém, Keszthely Márton L. 2000b. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Thesis. University of Veszprém, Keszthely Márton L. 2001a. Climete change effets on rye (Secale cereale L.) yield. Agrochemistry and Soil Science. Budapest. In press Márton L. 2001b. Climate change and fertilization effect analysis at the Tisza- river basin on rye yield. SZINET. University of Szent István. Gödöllő Márton L.-Kádár I.-Estáquio M.J. 2000. Effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH on soil fertility and soil conservation. ESSC. Man and Soil at the Third Millennium. Abstract Book. 195. Valencia Reifschneider F.J.B. 1987. Produção de batata. Linha Gráfica e Editora. Brasília. p. 239. Tabela 1. Tratamentos do experimento 1. (Brasília-DF, 1990) ------------------------------------------------------------------ Numero de Composição em % Tratamento Solo novo Palha de arroz queimado Esterco de curral ------------------------------------------------------------------ 1. 100 0 0 2. 90 6 4 3. 80 10 10 4. 70 18 12 5. 60 24 16 6. 50 30 20 7. 40 36 24 ----------------------------------------------------------------- Tabela 2. Tratamentos do experimento 2. (Brasília-DF, 1990) ------------------------------------------------------- Numero de Adubo 4:14:8 N P2O5 K2O Tratamento Grama vaso-1 ------------------------------------------------------- 1. 0.0 0.000 0.000 0.000 2. 1.8 0.072 0.252 0.144 3. 3.6 0.144 0.504 0.288 4. 5.4 0.216 0.756 0.432 5. 7.2 0.288 1.008 0.576 6. 9.0 0.360 1.260 0.720 7. 10.8 0.432 1.512 0.864 8. 12.6 0.504 1.764 1.008 9. 14.4 0.576 2.016 1.152 ------------------------------------------------------- Tabela 3. Tratamentos do experimento 3. (Brasília-DF, 1990) ------------------------------------------------------------------------ Num. de Mistura % Trat. Solo novo Palea de arr. Q Esterco de curral 4N:14P:8K g vaso-1 ------------------------------------------------------------------------ 1. 70 20 10 0.0 2 70 20 10 3.6 3. 70 20 10 7.2 4. 70 20 10 10.8 5. 70 20 10 14.4 6. 70 20 10 18.0 7. 80 10 10 0.0 8. 80 10 10 3.6 9. 80 10 10 7.2 10. 80 10 10 10.8 11. 80 10 10 14.4 12. 80 10 10 18.0 ------------------------------------------------------------------------

  18. Eco-hydrology: Groundwater flow and site factors in plant ecology

    NASA Astrophysics Data System (ADS)

    Klijn, Frans; Witte, Jan-Philip M.

    Résumé En écologie végétale, le site est un concept central. Un site, c'est l'endroit où une espèce végétale ou une communauté de plantes se développe le site assure un ensemble de conditions dans lesquelles elles vivent. Dans un matériau homogène à l'origine, l'écoulement gravitaire d'une nappe influence les conditions du site par l'intermédiaire de la distribution spatiale des nutriments et d'autres composés chimiques associés. Les remontées d'eau peuvent tout spécialement produire et maintenir les conditions du site essentielles pour différentes espèces et communautés de plantes relativement rares. Les écologues ont porté une attention accrue à ces remontées d'eau, en sorte qu'une coopération avec les hydrologues en a résulté, avec l'émergence d'une discipline propre, l'éco-hydrologie, à la limite des deux domaines scientifiques et liée au concept de site. Aux Pays-Bas, une classification des types d'eau, basée sur l'histoire de l'eau souterraine à proximité de la surface, a été mise en oeuvre pour constituer une base nationale de données géographiques sur les remontées d'eau d'intérêt écologique. Des analyses des correspondances des données de cette base, portant sur l'existence de certaines espèces de plantes, montrent que dans les sols sableux pauvres du Pléistocène la remontée d'eau explique très bien la présence de certaines espèces et communautés, alors que, dans les plaines fluviales et les régions de polders à sols argileux riches, l'influence de la remontée d'eau est masquée par l'importance des caractéristiques des sols. En conclusion donc, certaines espèces de plantes peuvent être utilisées comme des indicateurs de la remontée d'eau dans des diagnostiques et des levés de terrain rapides, mais à condition de prendre en permanence des précautions sur les limites de l'approche. Resumen En ecología botánica un concepto de gran importancia es el de emplazamiento, definido como el lugar que proporciona unas condiciones de vida adecuadas que permiten el crecimiento de una especie o una comunidad botánica. En un material inicialmente homogéneo, el flujo subterráneo gravífico influencia las condiciones del emplazamiento variando la distribución espacial de los nutrientes y de otros agentes químicos relevantes. En especial, el flujo ascendente puede producir y mantener una serie de condiciones que son esenciales para algunas especies y comunidades de plantas relativamente raras. La especial atención hacia este fenómeno ha dado lugar a una cooperación entre ecologistas e hidrogeólogos y a la aparición de una nueva disciplina - eco-hidrología -, en la frontera de los dos campos científicos. En Holanda, se ha usado una clasificación sencilla de tipos de agua para crear una base de datos, a nivel nacional, de lugares donde la presencia de flujos ascendentes pueda ser de interés ecológico. El análisis de correspondencias entre esta base de datos y los tipos de plantas existentes muestra que en los suelos arenosos pobres del Pleistoceno los flujos ascendentes explican la presencia de algunas especies y comunidades de plantas. Por el contrario, en las llanuras fluviales y pólders, con suelos más arcillosos, la influencia de estos flujos es despreciable frente a la relativa a las propias características de los suelos. Se concluye que las especies botánicas se pueden usar como indicadores de la presencia de flujo ascendente sólo en campañas preliminares, pero que el método presenta grandes limitaciones para su extensión a casos generales.

  19. Uvby-B Photometry of High Velocity Stars. Photometric Parallaxes and Preliminary Kinematic Results

    NASA Astrophysics Data System (ADS)

    Schuster, W. J.

    1990-11-01

    RESUMEN. Se han explorado dos metodos para la determinaci6n de paralajes fotometricos usando fotometrfa uv - . Estos metodos dependen de las relaciones estandar de Crawford (1975) y de Olsen (1984) y de colores y magnitudes sinteticas de VandenBerg y Bell (1985). Ambos metodos incluyen una correcci6n evolucionaria de forma f6c0. Se calculan las distancias para las 711 estrellas de alta velocidad y pobres en metales en el catalogo uvby-p de Schuster y Nissen (1988). Se comparan estas con las distancias de Sandage y Fouts (1987) y Laird, Carney y Latham (1988) para las estrellas en comtfin. Tambien son aplicables nuestros metodos a estrellas de paralaje. En general las comparaciones son satisfactorias y las sistematicas son despreciables o pequefias. Las distancias finales de nuestras 711 estrellas se aplican a un numero de problemas cinematicos. Se estudian algunos diagramas interesantes, tales como el diagrama de energia de Toomre y el diagrama V(rot) versus [Fe/H]. ABSTRACT Two methods for the determination of parallaxes using uvbyP photometry are being explored. These methods depend upon the standard relations of Crawford (1975) and of Olsen (1984) and upon synthetic colors and magnitudes of VandenBerg and Bell (1985). Both include an evolutionary correction of the form f6c0. Distances are calculated for the 711 high-velocity and metal-poor stars in the uvby-P catalogue of Schuster and Nissen (1988). These are compared to the distances of Sandage and Fouts (1987) and Laird, Carney, and Lathain (1988) for stars in common. Also our methods are applied to parallax stars. In general the comparisons are good with negligible or small systematic differences. The final distances of our 711 stars are applied to a number of kinematical problems. Several interesting diagrams are studied, sucl as Toomre energy diagram and the plot of V(rot) versus [Fe/H]. Key words: DISTANCES - PHOTOMETRY - STARS-POPULATION II

  20. Black Cohosh

    MedlinePlus

    ... of cells from columnar to squamous ) in ovariectomized rats [ 17 ]. What is the regulatory status of black ... on gonadotropin release in menopausal women and ovariectomized rats. Planta Medica 57: 420-424, 1991. [ PubMed abstract ] ...

  1. Trazando el brazo de Vela-Puppis

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Vzquez, R. A.; Baume, G. L.; Seggewiss, W.; Feinstein, A.

    Presentamos resultados preliminares basados en anlisis fotomtricos UBVI para 9 cmulos abiertos ubicados en la zona de Vela-Puppis (? =7h58m y 9h54m, ? =- 28o a -59o) sobre un total de 15 cmulos previstos. Estos cmulos no han sido observados previamente, excepto en algunos pocos casos que se cuenta con fotometra y espectroscospa de algunas estrellas. Se han determinado membrecias, excesos de color, distancias y edades. En el futuro, la muestra global permitir definir mas claramente este brazo y ser utilizada para estudiar las funciones iniciales de masa individuales e integradas y compararlas con las obtenidas en observaciones intensivas realizadas en otras zonas de la Galaxia.

  2. La distribucin de objetos en el Cinturn de Kuiper y la posible existencia de un nuevo planeta en el Sistema Solar

    NASA Astrophysics Data System (ADS)

    Brunini, A.

    A pesar de que la capacidad observacional no lo limita, no se han descubierto objetos en el Cinturn de Kuiper ms all de las 50 AU. Recientemente, hemos propuesto que un embrin planetario originalmente formado en la regin de Urano-Neptuno, y posteriormente migrado hacia distancias mayores a 50-60 AU, puede explicar este hecho. Presentamos simulaciones numricas de acrecin del Sistema Solar exterior que muestran cmo, naturalmente, podriamos esperar que un planeta de este tipo se encuentre actualmente en regiones distantes del sistema solar. Analizamos adems la posibilidad de detectarlo con instrumentos actuales.

  3. Hydraulic properties and scale effects investigation in regional rock aquifers, south-western Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Nastev, M.; Savard, M. M.; Lapcevic, P.; Lefebvre, R.; Martel, R.

    This paper reports on the characterization of hydraulic properties of regional rock aquifers carried out within a groundwater resources assessment project in the St. Lawrence Lowlands of south-western Quebec. To understand the aquifer behavior at both the fracture level and at field scale, hydraulic investigations were carried out using various aquifer tests. The groundwater flow at the local scale is controlled mostly by the fracture system. Results of the constant-head injection tests show a weak decreasing trend of hydraulic conductivity with depth indicating that a major part of the groundwater flow occurs in the first meters of the rock sequence. At the regional scale, the equivalent porous media approach is applicable. The hydraulic conductivity measurements were correlated to the scale of the aquifer tests expressed with the investigated aquifer volume. A simple interpolation procedure for the hydraulic conductivity field was developed based on the distance between field measurements and the tested aquifer volumes. The regional distribution of the hydraulic conductivity for the major fractured aquifer units indicates that dolostone is the most permeable whereas sandstone and crystalline rocks are the least permeable units. Este artículo trata de la caracterización de las propiedades hidráulicas en acuíferos regionales rocosos, la cual se llevó a cabo dentro del proyecto de evaluación de los recursos de agua subterránea en St. Lawrence Lowlands al suroeste de Quebec. Para entender el comportamiento del acuífero tanto a nivel de fractura como a escala del campo, se ejecutaron investigaciones hidráulicas usando varias pruebas de acuífero. El flujo del agua subterránea a escala local está controlado principalmente por el sistema de fracturas. Los resultados de las pruebas de inyección con cabeza constante muestran una tendencia decreciente débil de la conductividad hidráulica con la profundidad, indicando que la mayor parte del flujo de agua subterránea sucede en los primeros metros de la secuencia rocosa. A escala regional se puede aplicar la aproximación equivalente de medios porosos. Las medidas de la conductividad hidrálica fueron comparadas con la escala de las pruebas del acuífero, expresadas con el volumen investigado del acuífero. Se desarrolló un proceso de interpolación simple para la conductividad hidráulica de campo, con base en la distancia entre las medidas de campo y los volúmenes probados del acuífero. La distribución regional de la conductividad hidráulica, para las unidades acuíferas fracturadas mayores, indica que la dolomita es más permeable mientras que la arenisca y las rocas cristalinas son las unidades menos permeables. L'article présente les propriétés hydrauliques d'un aquifère régional rocheux qui ont été mesurées dans le cadre d'un projet concernant l'estimation de la ressource en eau de la plaine de St. Lawrence située dans la partie sud-ouest de Quebec. Affin de comprendre le comportement de l'aquifère tant à l'échelle de fracture qu'à l'échelle régionale on a mené des investigations hydrauliques en utilisant des essais differents. À l'échelle locale l'écoulement est déterminé en principal par le système des fractures. Les résultats des essais d'injection au niveau constant ont montré une tendence de décroissance de la conductivité hydraulique avec la profondeur ce qui indique que l'écoulement ait lieu en principal dans les premiers mètres de la structure rocheuse. À l'échelle règionale on peut appliquer l'approche de milieux poreux equivalent. Les mesures de conductivité hydraulique ont été corrélées avec l'échelle des essais de pompage exprimée en termes de volume investigué de l'aquifère. On a mis au point une méthode simple d'interpolation pour le champ de la conductivité hydraulique basée sur la distance entre les essais in situ et les volume investigués de l'aquifère. La distribution règionale de la conductivité hydraulique montre que pour la majorité des unités de roche fracturé les plus perméable sont les roches dolomitiques alors que les grés et les roches cristalines presentent la plus faible perméabilité.

  4. Estudio de la influencia de la refrigeracion con aire de forma natural e inducida en el comportamiento de instalaciones fotovoltaicas

    NASA Astrophysics Data System (ADS)

    Mazon Hernandez, Rocio

    The aim is to analyse the negative influence of high panel temperatures on electrical production when they are placed on steel roofs of industrial buildings and greenhouse roofs. Different configurations have been tested in order to allow cooling of photovoltaic panels to decrease panel temperature and improve electrical performance. To research this problem two experimental facilities have been built. The first facility includes two panels fixed on a structure. A panel is integrated on a parallel steel plate which does not allow sufficient cooling. Between both surfaces, there is an open air channel in which an air flow is created by the chimney effect thus cooling the panel by natural convection or inducing air, using a fan, by forced convection. The other panel has not any plate underneath it and is used as a referent. The electrical behaviour of the integrated panel has been studied for different air gaps and induced velocities, being also compared with the reference panel. An experimental model was developed to establish correlations which allow determine the panel temperature depending on the influential variables on the cooling ability. This research also analyses the data of a working solar plant, with the same panel model, obtaining the correlations between electrical variables and panel temperature. A comparison with the electrical behaviour in the experimental facility and the solar plant is also presented. The second experimental facility is a replica of a photovoltaic greenhouse. It consists of four photovoltaic panels placed on the plastic roof, providing an open and divergent channel between both surfaces thus creating an air flow by natural convection. This research studies the effect of high temperatures within the greenhouse which is transferred by the roof and thus affects the electrical production. In addition, two air gaps were used and the effect of adding insulating material to the plastic roof was studied. The electrical variables of the panels are analysed to compare and select the best configuration. The presented research provides a deep knowledge of how they work as well as information and results for an improvement in future designs of building integrated photovoltaic systems. Este estudio se centra en analizar la influencia negativa de la temperatura en la produccion electrica de paneles fotovoltaicos al estar emplazados sobre cubierta de acero, como sucede en naves industriales y sobre un invernadero. Se estudian diferentes configuraciones que permitan refrigerar los paneles, reduciendo su temperatura y mejorar su rendimiento. Para abordar este problema, se han construido dos instalaciones experimentales, fieles a plantas solares en funcionamiento. Una instalacion engloba dos paneles fotovoltaicos sobre estructura fija al suelo. Uno de los paneles esta integrado sobre una superficie paralela y metalica. Entre ambas superficies existe un espacio que posibilita circular aire, permitiendo refrigerar el panel por conveccion natural, o conveccion forzada impulsando el aire con un ventilador. El otro panel, libre por su cara posterior y se ha considerado de referencia. Se ha estudiado el comportamiento del panel integrado sobre cubierta para diferentes secciones de aire y velocidades inducidas, comparandolo con el panel de referencia. Se ha desarrollado un modelo experimental que nos permite determinar la temperatura del panel en funcion de las variables que influyen en su refrigeracion. Adicionalmente, se han analizado los datos de una planta solar en funcionamiento, con paneles de igual caracteristicas, obteniendo correlaciones entre la temperatura del panel y las variables electricas y comparandolos con las obtenidas en la instalacion experimental. La segunda instalacion experimental reproduce parte de una instalacion solar sobre un invernadero, formada por cuatro paneles fotovoltaicos colocados sobre el plastico del invernadero, existiendo un canal divergente entre ambas superficies. Se estudia la influencia de las altas temperaturas en el interior del invernadero sobre la produccion electrica de los paneles, decido a la transferencia de calor del interior del invernadero. Ademas, se han ensayado dos separaciones diferentes y para cada una se ha comparado con la misma, utilizando un aislante sobre la cubierta. El estudio realizado sobre ambas instalaciones ha proporcionado un conocimiento profundo del funcionamiento de cada una de ellas, asi como informacion valida para una mejora de futuros disenos de instalaciones fotovoltaicas sobre cubiertas.

  5. Phytoreovirus-like sequences isolated from salivary glands of the glassy-winged sharpshooter Homolodisca vitripennis (Hemiptera: Cicadellidae)

    SciTech Connect

    Katsar, C.S.; Hunter, W.B. . E-mail: Whunter@ushrl.ars.usda.gov; Sinisterra, X.H.

    2007-03-15

    The salivary glands of the Glassy-winged sharpshooter (GWSS), Homalodisca vitripennis Germar 1821, (syn. H. coagulata, Hemiptera: Cicadellidae) were collected and used to produce a cDNA library. Examination by BLASTX analyses identified 2 viral sequences, one a 610-base pair fragment and a second 839-base pair fragment, both of which had significant homology to viruses within the genus Phytoreovirus. Resequencing of the fragments confirmed sequence validities. These sequences were used for in silico protein translation and BLASTP analysis confirming the established homology. While the GWSS is the primary vector of Pierce's disease of grapes, this is the first report that GWSS may be a vector of a phytoreoviruses. Phylogenetic and homology comparisons with BLASTX, BLASTP, and PAUP analyses indicated that the viral sequences isolated from GWSS were closely related to the viruses in the Family Reoviridae, Genus Phytoreovirus, specifically Rice Dwarf Phytoreovirus (RDV). RDV is the only plant reovirus that is not limited to the phloem. Phytoreoviruses are transmitted in a propagative manner by cicadellid leafhoppers (Hemiptera: Cicadellidae), which acquire and transmit them during feeding. Phytoreoviruses have been reported from Agallian, Agalliopsis, Nephotettix, and Recilia, genera of leafhoppers, with evidence for transovarial transmission. The GWSS, although considered to feed primarily from the xylem, ingests from other plant tissues, such as the phloem and mesophyll during probing similar to other leafhoppers. The feeding behavior and wide host range of the GWSS provides an overlapping condition for these two organisms, leafhopper and virus. GWSS will feed from grasses as a transitory host, and on herbaceous and woody plants as primary hosts, which may favor the acquisition and transmission of Phytoreovirus by this leafhopper. Monitoring for an increase of Phytoreovirus spread in graminaceous crops that are in proximity to vineyards or tree crop orchards, where GWSS occurs, such as in southern California, will provide a better understanding of the potential role of the GWSS as a disease vector in the spread of phytoreoviruses and other plant pathogens. The sequences have been deposited in NCBI database under the accession numbers (EF058280) for GWSS-V1, WHSg013C11 and (EF058281) for GWSS-V2, WHSg024H02. (author) [Spanish] Dos fragmentos de 610 y 839 pares de bases fueron aislados apartir de una genoteca de expresion derivada de las glandulas salivales del cucarron de las alas cristalinas (GWSS), Homalodisca vitripennis, Germar 1821 (syn. H. coagulata) el cual es vector de la enfermedad de Pierce de las uvas. Los resultados de alineamiento utilizando BLASTX, BLASTP y el analisis filogenetico utilizando PAUP indicaron que los fragmentos de DNA estaban relacionado de manera mas cercana a viruses en la familia Reoviridae, genero Phytoreovirus, y especificamente a los virus del enanismo del arroz (RDV) y al virus del tumor de las grietas (WTV). El cucarron de las alas cristalinas es un saltahoja que se alimenta no solo del xilema sino tambien del floema y del mesofilo. Saltahojas del genero Agallian, son los principales vectores de WTV, el cual infecta el floema de plantas dicotiledoneas tumoraciones en las hojas y en las raices. WTV es transmitido por saltahojas y es el unico reovirus que es capaz de infectar tanto tejidos del xilema como del floema. El comportamiento alimentario del GWSS y su amplio rango de hospederos que incluye pastos y plantas herbaceas y lenosas podria proveer la interaccion entre estos dos organismos facilitando la adquisicion y tranmision de fitoreovirus por el GWSS. Un adecuado monitoreo de el incremento en la expansion de reoviruses en cultivos de gramineas asociados al los vinedos en donde GWSS ocurre en regiones tales como el sur de California, y en general el sur de los Estados Unidos, podria proveer un mejor entendimiento del papel del GWSS como vector de fitoreovirus y otros patogenos de plantas. Las sequencias se depositaron en la base de datos NCBI con los siguientes numeros de identificacion: (EF058280) para GWSS-V1, WHSg013C11 y (EF058281) para GWSSV2, WHSg024H02. (author)

  6. Geostatistical mapping of leakance in a regional aquitard, Oak Ridges Moraine area, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Desbarats, A. J.; Hinton, M. J.; Logan, C. E.; Sharpe, D. R.

    2001-01-01

    The Newmarket Till forms a regionally extensive aquitard separating two major aquifer systems in the Greater Toronto area, Canada. The till is incised, and sometimes eroded entirely, by a network of sand- and gravel-filled channels forming productive aquifers and, locally, high-conductivity windows between aquifer systems. Leakage through the till may also be substantial in places. This study investigates the spatial variability of aquitard leakance in order to assess the relative importance of recharge processes to the lower aquifers. With a large database derived from water-well records and containing both hard and soft information, the Sequential Indicator Simulation method is used to generate maps of aquitard thickness and window probability. These can be used for targeting channel aquifers and for identifying potential areas of recharge to the lower aquifers. Conductivities are modeled from sparse data assuming that their correlation range is much smaller than the grid spacing. Block-scale leakances are obtained by upscaling nodal values based on simulated conductivity and thickness fields. Under the "aquifer-flow'' assumption, upscaling is performed by arithmetic spatial averaging. Histograms and maps of upscaled leakances show that heterogeneities associated with aquitard windows have the largest effect on regional groundwater flow patterns. Résumé. La moraine glaciaire de Newmarket constitue un imperméable d'extension régionale séparant deux systèmes aquifères dans la région du Grand Toronto (Canada). La moraine est entaillée, et parfois entièrement érodée, par un réseau de chenaux comblés de sables et de graviers formant des aquifères productifs et, localement, des «fenêtres», zones à forte conductivité hydraulique reliant les systèmes aquifères. Une drainance au travers de la moraine peut également être significative par endroits. Cette étude s'intéresse à la variabilité spatiale de la drainance au travers de l'imperméable, dans le but d'évaluer l'importance relative des processus d'alimentation des aquifères inférieurs. À partir d'une vaste base de données constituée par les mesures faites dans les puits et contenant des informations à la fois certaines et incertaines, la méthode de simulation par indicateur séquentiel est utilisée pour créer des cartes d'épaisseur de l'imperméable et de probabilité d'existence des fenêtres. Ces cartes peuvent être utilisées pour mettre en évidence les aquifères de chenaux et pour identifier les zones potentielles de recharge des aquifères inférieurs. Les conductivités hydrauliques sont modélisées à partir de données clairsemées en supposant que leur gamme de corrélation est beaucoup plus faible que le pas de la grille. La drainance à l'échelle des blocs est obtenue par accroissement du niveau d'échelle des valeurs nodales basé sur les champs de conductivité simulée et des épaisseurs. À partir de l'hypothèse d'écoulement dans l'aquifère, l'accroissement d'échelle est réalisé en faisant une moyenne arithmétique spatiale. Des histogrammes et des cartes de drainance avec accroissement d'échelle montrent que les hétérogénéités associées aux fenêtres dans l'imperméable constituent l'effet le plus important dans l'organisation des écoulements souterrains régionaux. Resumen. El Till de Newmarket forma un acuitardo de extensión regional que separa dos sistemas acuíferos principales en la zona de Greater Toronto (Canadá). El till está horadado, y a veces completamente erosionado, por una red de canales rellenos de arena y grava. Estos constituyen acuíferos productivos y, localmente, conexiones de alta permeabilidad entre sistemas acuíferos. El goteo a través del till puede ser fundamental en ciertos lugares. Este estudio investiga la variabilidad espacial del goteo desde el acuitardo con el fin de establecer la importancia relativa de los procesos de recarga hacia los acuíferos inferiores. Se ha utilizado el método de la Simulación Indicadora Secuencial, soportado por una gran base de datos que contiene registros de sondeos e incluye información blanda y dura, para generar mapas de espesor del acuitardo y mapas de probabilidad de discontinuidades laterales en el acuitardo. Estos resultados se pueden emplear para identificar canales y las zonas de recarga potencial a los acuíferos inferiores. Se han modelado las conductividades a partir de datos dispersos, suponiendo que la distancia de correlación es mucho menor que el espaciado de la malla. Se han calculado valores de goteo a escala de bloque por medio del escalado de los valores nodales, basándose en los campos simulados de conductividad y espesor. El escalado se calcula mediante un promedio aritmético espacial, bajo la hipótesis de "flujo en el acuífero". Los histogramas y mapas de goteos escalados muestran que las heterogeneidades asociadas a las discontinuidades en el acuitardo producen el efecto más notable en la distribución regional del flujo de aguas subterráneas.

  7. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    We present the results obtained in a research on the comprehension of basic astronomical concepts, in which 561 students from fifth grade middle school to third grade high school of a public school of the city of Foz do Iguaçu (Brazil) took part. A test with 20 multiple-choice questions was applied to indentify the most common conceptions expressed by the students. This test was elaborated based on the literature about misconceptions and covered the following topics: the day-night cycle; the time zones; the seasons of the year; the phases of the Moon; the movement of the Moon; the apparent movement of the Sun in the celestial sphere; the eclipses; the dimensions and distances in the Universe; the brightness of the stars and its observation from Earth. Though a small progress was verified in the proportion of scientifically acceptable answers when comparing the eighth grade of middle school to the fifth, and the third grade of high school to the first, there was an overall predominance of alternative conceptions regarding most of the explored subjects, which persisted up to the last year of secondary school. The comparison to data found in this research made in other socio-cultural contexts revealed, in many aspects, similar notions and difficulties revealed by the students. Se presentan los resultados de una investigación sobre la comprensión de conceptos astronómicos básicos, en la cual participaron 561 estudiantes que cursaban entre el quinto grado de la enseñanza primaria y el tercer año de la enseñanza secundaria de una escuela pública de la ciudad de Foz do Iguaçu (Brasil). Se utilizó un test de 20 preguntas de opción múltiple para identificar las concepciones más comunes expresadas por los estudiantes. Este instrumento de recolección de datos se desarrolló en base a la literatura sobre las concepciones alternativas y trató los siguientes temas: el ciclo día-noche, los husos horarios, las estaciones del año, las fases de la Luna, el movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com dados encontrados em investigações realizadas em outros contextos socioculturais revelaram, em muitos aspectos, noções e dificuldades similares manifestadas pelos estudantes.

  8. Human Relations Activities for the Single Parent To Develop More Effective Parent/Child Relations. Bilingual Guide = Actividades sobre relaciones humanas para ayudar al padre-soltero o madre-soltera a desarrollar una relacion efectiva entre padre e hijo Guia bilingue.

    ERIC Educational Resources Information Center

    Peterson, Susan

    Written in English and Spanish, this bilingual guide offers 10 activities which single parents can use to improve their relationships with their children. Objectives of activities include: (1) developing children's responsibility for work tasks in the home; (2) improving sibling relationships; (3) discussing emergencies with children; (4)

  9. Executive Summary of The Use of Educational Software in Adult Literacy Programs: A Comparison of Integrated Learning Systems and Stand-Alone Software=Resume du Rapport Intitule: L'Utilisation de Didacticiels dans les Programmes d'Alphabetisation des Adultes: Une Comparaison Entre les Systemes Integres d'Apprentissage et les Logiciels Autonomes.

    ERIC Educational Resources Information Center

    Millar, Diane

    The pros and cons of integrated learning systems (ILS) and stand-alone software for adult literacy instruction were examined in a comparative analysis that focused on their use in adult literacy programs in Canada. The comparison focused on the following variables: achievement gains in reading; changes in students' attitudes toward computers;

  10. L'impact de l'enseignement de la biologie sur la construction de la distinction entre normal et pathologique chez les eleves du secondaire Marocain (The Impact of Teaching Biology on the Way Moroccan High School Students Construe the Difference between Normal and Pathological).

    ERIC Educational Resources Information Center

    Khzami, Salah-Eddine; Favre, Daniel

    2002-01-01

    Study of the distinction between the notions of the normal and the pathological among Moroccan high school students and their teachers of biology found that students confused the registers of the normal/abnormal with the healthy/pathological, a fact that is at odds with current teaching in biology. It also found a possible link to the values held…

  11. How To Talk to Your Doctor (and Get Your Doctor To Talk to You!). An Educational Workshop on Doctor Patient Communication = Como Hablarle a su Doctor (iY que su doctor le hable a usted!). Un seminario educativo sobre la comunicacion entre el doctor y el paciente.

    ERIC Educational Resources Information Center

    Baylor Coll. of Medicine, Houston, TX.

    This workshop, written in both English and Spanish, focuses on improving communication between physician and patient. In the workshop, the trainers will talk about "building bridges" between patient and doctor by understanding the doctor's role and his/her duty to the patient. According to the workshop, a person's doctor should communicate…

  12. Global Professional Identity in Deterretorialized Spaces: A Case Study of a Critical Dialogue between Expert and Novice Nonnative English Speaker Teachers (Identidad profesional global en espacios desterritorializados: un estudio de caso de los diálogos críticos entre profesores de inglés no nativos)

    ERIC Educational Resources Information Center

    Guerrero Nieto, Carmen Helena; Meadows, Bryan

    2015-01-01

    This study analyzes the online, peer-peer dialogue between two groups of nonnative English-speaking teachers who are attending graduate programs in Colombia and the United States. Framed by the theoretical concepts of critical pedagogy and global professional identity, a qualitative analysis of the data shows that their expert vs. novice roles…

  13. Human Relations Activities for the Single Parent To Develop More Effective Parent/Child Relations. Bilingual Guide = Actividades sobre relaciones humanas para ayudar al padre-soltero o madre-soltera a desarrollar una relacion efectiva entre padre e hijo Guia bilingue.

    ERIC Educational Resources Information Center

    Peterson, Susan

    Written in English and Spanish, this bilingual guide offers 10 activities which single parents can use to improve their relationships with their children. Objectives of activities include: (1) developing children's responsibility for work tasks in the home; (2) improving sibling relationships; (3) discussing emergencies with children; (4)…

  14. Efectos Especiales de Anclaje (Estudio sobre Regresiones de Juicios Condicionales). Parte 1: Distincion entre Efectos Aditivos y Efectos Multiplicativos en el Fenomeno de Anclaje (Special Effects of Anchoring (Study on Regression of Conditional Judgements) Part 1: Distinction Between Additive Effects and Multiplicative Effects in the Phenomenon of Anchoring). Publication No. 17.

    ERIC Educational Resources Information Center

    Lopez Alonso, A. O.

    A linear relationship was found between judgements given by 160 subjects to 7 objects presented as single stimuli (alpha judgements) and judgements given to the same objects presented with a condition (gamma judgements). This relationship holds for alpha judgements and the gamma judgements that belong to a family of constant stimulus and varying…

  15. El juego entre el nacimiento y los 7 anos: Un manual para ludotecarias. Investigacion-accion sobre la Familia y la Primera Infancia. UNESCO Sector de Educacion Monografia (Play between Birth and 7 Years: A Manual for Preschool Teachers. Action Research in Family and Early Childhood. UNESCO Education Sector Monograph).

    ERIC Educational Resources Information Center

    Grellet, Carolina

    The purpose of this Spanish-language manual is to help preschool teachers better understand theoretical concepts related to children's play. Following a preface that discusses UNESCO's activities related to early childhood education, the two main sections of the manual discuss children's play between 0-2 years and 2-7 years. Each section includes…

  16. Construyendo un Puente entre la Educacion del Dotado y el Mejoramiento Escolar Integral. Resumen. La Serie de Decision Basada en la Investigacion (Building a Bridge between Gifted Education and Total School Improvement. Summary. Talent Development Research-Based Decision Making Series).

    ERIC Educational Resources Information Center

    Renzulli, Joseph S.

    This monograph addresses the role of gifted education in total school improvement by describing three service delivery components (the Total Talent Portfolio, Curriculum Modification Techniques, and Enrichment Learning and Teaching) and several organizational components of the Schoolwide Enrichment Model (SEM). The report describes how the SEM can…

  17. En sus marcas--Listos--A leer! Para los cuidadores de ninos pequenos: Actividades de lenguaje para la primera infancia y ninez entre el nacimiento y los 5 anos. El reto: A leer, America! (Ready--Set--Read! For Caregivers: Early Childhood Language Activities for Children from Birth through Age Five. America Reads Challenge).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This Ready--Set--Read Kit includes an activity guide for caregivers, a 1997-98 early childhood activity calendar, and an early childhood growth chart. The activity guide presents activities and ideas that caregivers (family child care providers and the teachers, staff, and volunteers in child development programs) can use to help young children…

  18. En sus marcas--Listos--A leer! Para las familias: Actividades de lenguaje para la primera infancia y ninez entre el nacimiento y los 5 anos. El reto: A leer, America! (Ready--Set--Read! For Families: Early Childhood Language Activities for Children from Birth through Age Five. America Reads Challenge).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This Ready--Set--Read Kit includes an activity guide for families, a 1997-98 early childhood activity calendar, and an early childhood growth wallchart. The activity guide presents activities and ideas that families (adults who have nurturing relationships with a child--a mother, father, grandparent, other relative, or close friend) can use to…

  19. Apports des phyllosilicates dans la différenciation entre altération hypogène et altération supergène dans le basalte triasique du Moyen Atlas (Maroc)Contribution of phyllosilicates to distinguish between hypogene alteration and weathering in Triassic basalt from Middle Atlas (Morocco)

    NASA Astrophysics Data System (ADS)

    Dekayir, Abdelilah; Danot, Michel; Allali, Nabil

    2002-09-01

    Triassic basalt of the Middle Atlas has been subject to metamorphic transformation then weathering. Occurrence in both metabasalt and saprolite of ubiquitous clay minerals, such as smectite and mixed layers chlorite-smectite, makes it difficult to distinguish between the two alteration facies and explains the interest of complementary sources of information. In the Bhallil weathering profile, petrographical and mineralogical analyses of primary igneous minerals and their alteration products coupled with Fe oxidation state determination in clay fractions allow to identify three alteration facies: ( i) metamorphic basalt, where iron occurs mainly as the ferrous form; ( ii) the lower part of saprolite, where iron is partially oxidized to its ferric form; ( iii) the upper part of saprolite, where iron is completely oxidized. To cite this article: A. Dekayir et al., C. R. Geoscience 334 (2002) 877-884.

  20. Synergie entre la télédétection multispectrale et les données de terrain pour la conception d'un nouveau modèle géodynamique d'ouverture du bassin paléozoîque des Jebilet centrales (Maroc)

    NASA Astrophysics Data System (ADS)

    El Harti, Abderrazak; Bannari, Abderrazak; Bachaoui, El Mostafa; Aarab, El Mostafa; Girouard, Guillaume; El Ghmari, Abderrahmen

    2004-11-01

    The geodynamic model of the Palaeozoic basin opening of central Jebilet has been unknown before this study in spite of the abundance in the geological studies carried out in the studied sector using conventional methods. This is due to the scarcity of the key beds and synsedimentary structures. Using the synergy between the image data of the Landsat satellite TM sensor and the ground data, we have highlighted, herein, new structural data allowing the design of a new model of the Palaeozoic basin opening of central Jebilet. This opening could have been made according to dextral submeridian transverse faults with the individualization of subequatorial normal faults. To cite this article: A. El Harti et al., C. R. Geoscience 336 (2004).

  1. Resumes de texte en langue maternelle et en langue seconde: Differences dans l'application des macroregles entre experts et etudiants de differents niveaux universitaires (Test Summaries in the Mother Tongue and in a Second Language: Differences in the Application of Macrorules between Experts and University Students of Various Levels).

    ERIC Educational Resources Information Center

    Corbeil, Giselle

    2001-01-01

    Analyzes differences between experts and university students of various academic levels in the application of the macrorules of deletion, generalization, and construction of text summaries. Learners of French as a second language wrote summaries of a French text in French as well as in English, their mother tongue, while professors of French and…

  2. Le complexe annulaire d'âge Oligocène de l'Achkal (hoggar Central, Sud Algérie) : témoin de la transition au Cénozoïque entre les magmatismes tholéitique et alcalin. Évidences par les isotopes du Sr, Nd et Pb

    NASA Astrophysics Data System (ADS)

    Maza, Mustapha; Briqueu, Louis; Dautria, Jean-Marie; Bosch, Delphine

    1998-08-01

    The Achkal Oligocene ring complex cross-cuts the Upper Eocene tholeiitic traps located on the top of the Hoggar swell. The plutonic rocks range from tholeiitic gabbros to alkali essexites, monzonites and syenites, whereas the volcanites are restricted to late peralkaline rhyolites. The affinity change linked to the large isotopic heterogeneities (from EM1 to HIMU) suggests that the parental magmas are issued from two distinct mantle sources, first lithospheric then deeper. The Achkal has recorded the magmatic evolution of the Hoggar hot spot, between Eocene and Miocene.

  3. Linking: Today's Libraries, Tomorrow's Technologies. Report of the Bibliographic and Communications Network Pilot Project. Canadian Network Papers Number 7 = Le Lien entre les Bibliotheques d'Aujourd'hui et les Technologies de Demain. Rapport du Projet Pilote du Reseau de Services Bibliographiques et de Communications. Documents sur les Reseaux Canadiens Numero 7.

    ERIC Educational Resources Information Center

    National Library of Canada, Ottawa (Ontario).

    A pilot project was conducted from May 1980 to November 1983 to test the application of iNet--a decentralized, packet-switched telecommunications network--to bibliographic data interchange in Canada. The principal components of the project were participation of the Bibliographic Common Interest Group (BCIP), a group of libraries with stand-alone,

  4. Contamination par le nickel et d'autres métaux lors de la manipulation des pièces de monnaie comparaison entre francs français et eurosContamination by nickel and other metals resulting from the manipulation of coins comparison between French francs and euros

    NASA Astrophysics Data System (ADS)

    Fournier, P.-G.; Govers, T. R.; Fournier, J.; Abani, M.

    The introduction of the euro has revived the interest for potential nickel allergies. We show that the handling of a single used nickel coin releases an average of 0.45 μg of nickel, 0.26 μg of copper and 0.08 μg of zinc, whereas a euro coin composed of nickel alloys releases 0.25 μg of nickel, 1.3 μg of copper and 0.17 μg of zinc. These levels of contamination, favored by friction during handling, differ from those obtained on the basis of the EN 1811 test applicable to solubilisation in artificial sweat. The evaluation of allergy risks following the introduction of the euro may require the consideration of potential synergies between the metals mentioned above. To cite this article: P.-G. Fournier et al., C. R. Physique 3 (2002) 749-758.

  5. Linking: Today's Libraries, Tomorrow's Technologies. Report of the Bibliographic and Communications Network Pilot Project. Canadian Network Papers Number 7 = Le Lien entre les Bibliotheques d'Aujourd'hui et les Technologies de Demain. Rapport du Projet Pilote du Reseau de Services Bibliographiques et de Communications. Documents sur les Reseaux Canadiens Numero 7.

    ERIC Educational Resources Information Center

    National Library of Canada, Ottawa (Ontario).

    A pilot project was conducted from May 1980 to November 1983 to test the application of iNet--a decentralized, packet-switched telecommunications network--to bibliographic data interchange in Canada. The principal components of the project were participation of the Bibliographic Common Interest Group (BCIP), a group of libraries with stand-alone,…

  6. Mitigation of Disagreement in Peer Review among L2 Learners and Native Speakers in a College Writing Class (Mitigación del Impacto de las Opiniones de Desacuerdo en el Proceso de Revisión por Pares entre Estudiantes de una Segunda Lengua y Hablantes Nativos en una Clase de Escritura a Nivel Universitario)

    ERIC Educational Resources Information Center

    Christoffersen, Katherine O'Donnell

    2015-01-01

    Peer review is now a commonplace practice in process-oriented writing instruction. A crucial aspect of peer review is assessing another classmate's work, which encompasses the act of disagreement. Given its prevalence in the classroom, it is necessary to analyze how L2 learners mitigate disagreement in the context of peer review with other L2…

  7. Executive Summary of The Use of Educational Software in Adult Literacy Programs: A Comparison of Integrated Learning Systems and Stand-Alone Software=Resume du Rapport Intitule: L'Utilisation de Didacticiels dans les Programmes d'Alphabetisation des Adultes: Une Comparaison Entre les Systemes Integres d'Apprentissage et les Logiciels Autonomes.

    ERIC Educational Resources Information Center

    Millar, Diane

    The pros and cons of integrated learning systems (ILS) and stand-alone software for adult literacy instruction were examined in a comparative analysis that focused on their use in adult literacy programs in Canada. The comparison focused on the following variables: achievement gains in reading; changes in students' attitudes toward computers;…

  8. [The EMECAM protocol: an analysis of the short-term effect of air pollution on mortality. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica u la Mortalidad].

    PubMed

    Pérez-Hoyos, S; Sáez Zafra, M; Barceló, M A; Cambra, C; Figueiras Guzmán, A; Ordóñez, J M; Guillén Grima, F; Ocaña, R; Bellido, J; Cirera Suárez, L; López, A A; Rodríguez, V; Alcalá Nalvaiz, T; Ballester Díez, F

    1999-01-01

    The aim of this study is to Mortality show the protocol of analysis which was set out as part of the EMECAM Project, illustrating the application thereof to the effect of pollution has on the mortality in the city of Valencia. The response variables considered will be the daily deaths rate resulting from all causes, except external ones. The explicative variables are the daily series of different pollutants (black smoke, SO2, NO2, CO, O3). As possible confusion variables, weather factors, structural factors and weekly cases of flu are taken into account. A Poisson regression model is built up for each one of the four deaths series in two stages. In the first stage, a baseline model is fitted using the possible confusion variables. In the second stage, the pollution variables or the time legs thereof are included, controlling the residual autocorrelation by including mortality time lags. The process of fitting the baseline model is as follows: 1) Include the significant sinusoidal terms up to the sixth order. 2) Include the significant temperature or temperature squared terms with the time lags thereof up to the 7th order. 3) Repeat this process with the relative humidity. 4) Add in the significant terms of calendar years, daily tendency and tendency squared. 5) The days of the week as dummy variables are always included in the model. 6) Include the holidays and the significant time lags of up to two weeks of flu. Following the reassessment of the model, each one of the pollutants and the time lags thereof up to the fifth order are proven out. The impact is analyzed by six-month periods, including interaction terms. PMID:10410600

  9. Tensions entre rationalité technique et intérêts politiques : l’exemple de la mise en œuvre de la Loi sur les agences de développement de réseaux locaux de services de santé et de services sociaux au Québec

    PubMed Central

    Contandriopoulos, D.; Hudon, Raymond; Martin, Elisabeth; Thompson, Daniel

    2013-01-01

    Sommaire L’objet de cet article est constitué par les processus décisionnels entourant la mise en œuvre de la Loi sur les agences de développement de réseaux locaux de services de santé et de services sociaux (Loi 25). Nous entendons mettre en lumière les stratégies des groupes ou institutions de diverses natures qui ont fait valoir leurs préférences et ont tenté, avec un succès inégal, d’influencer les décisions relatives à cette réforme majeure de la structure du système de santé québécois. Au plan théorique, nous nous appuyons principalement sur les modèles d’analyse du lobbying qui, depuis les travaux fondateurs de Milbrath (1960, 1963), présentent cette pratique comme un processus fondamental d’échange d’information. Selon les données colligées dans les retranscriptions d’entrevues, les stratégies observées correspondent effectivement aux caractéristiques constitutives du lobbying et, dans quelques situations, à celles du patronage. La combinaison de ces divers éléments révèle que la mise en œuvre de la Loi 25 s’avère être avant tout un processus proprement politique. Ainsi, furent relégués au second plan les arguments techniques qui composaient initialement les objectifs de la Loi. PMID:23509412

  10. Spatial patterns of carbon, biodiversity, deforestation threat, and REDD+ projects in Indonesia

    PubMed Central

    Murray, Josil P; Grenyer, Richard; Wunder, Sven; Raes, Niels; Jones, Julia PG

    2015-01-01

    There are concerns that Reduced Emissions from Deforestation and forest Degradation (REDD+) may fail to deliver potential biodiversity cobenefits if it is focused on high carbon areas. We explored the spatial overlaps between carbon stocks, biodiversity, projected deforestation threats, and the location of REDD+ projects in Indonesia, a tropical country at the forefront of REDD+ development. For biodiversity, we assembled data on the distribution of terrestrial vertebrates (ranges of amphibians, mammals, birds, reptiles) and plants (species distribution models for 8 families). We then investigated congruence between different measures of biodiversity richness and carbon stocks at the national and subnational scales. Finally, we mapped active REDD+ projects and investigated the carbon density and potential biodiversity richness and modeled deforestation pressures within these forests relative to protected areas and unprotected forests. There was little internal overlap among the different hotspots (richest 10% of cells) of species richness. There was also no consistent spatial congruence between carbon stocks and the biodiversity measures: a weak negative correlation at the national scale masked highly variable and nonlinear relationships island by island. Current REDD+ projects were preferentially located in areas with higher total species richness and threatened species richness but lower carbon densities than protected areas and unprotected forests. Although a quarter of the total area of these REDD+ projects is under relatively high deforestation pressure, the majority of the REDD+ area is not. In Indonesia at least, first-generation REDD+ projects are located where they are likely to deliver biodiversity benefits. However, if REDD+ is to deliver additional gains for climate and biodiversity, projects will need to focus on forests with the highest threat to deforestation, which will have cost implications for future REDD+ implementation. Los Patrones Espaciales del Carbono, la Biodiversidad, la Amenaza de Deforestación y los Proyectos REDD+ en Indonesia Resumen Actualmente hay preocupación por que las Emisiones Reducidas de la Deforestación y Degradación del Bosque (REDD+, en inglés) puedan fallar en la entrega de co–beneficios potenciales de la biodiversidad si se enfocan en áreas de alto carbono. Exploramos los traslapes espaciales entre los stocks de carbono, la biodiversidad, las amenazas proyectadas de deforestación y la ubicación de proyectos REDD+ en Indonesia, un país tropical a la vanguardia del desarrollo REDD+. Para la biodiversidad, reunimos datos sobre la distribución de vertebrados terrestres (hábitats de anfibios, mamíferos, aves y reptiles) y plantas (modelos de distribución de especies para ocho familia). Después investigamos la congruencia entre las diferentes medidas de la riqueza de la biodiversidad y los stocks de carbono en la escala nacional y sub–nacional. Finalmente mapeamos proyectos REDD+ activos e investigamos la densidad de carbono y la riqueza potencial de la biodiversidad y modelamos presiones de deforestación dentro de estos bosques en relación con áreas protegidas y no protegidas. Hubo poco traslape interno entre los diferentes hotspots (el 10% más rico de las celdas) de riqueza de especies. Tampoco hubo congruencia espacial consecuente entre los stocks de carbono y las medidas de la biodiversidad: una correlación negativa débil en la escala nacional enmascaró las relaciones altamente variables y no-lineales isla por isla. Los proyectos REDD+ actuales estuvieron ubicados preferencialmente en áreas con una riqueza total de especies y con una riqueza de especies amenazadas más altas pero con densidades de carbono más bajas que en las áreas protegidas y los bosques sin protección. Aunque un cuarto del área total de estos proyectos REDD+ está bajo una presión de deforestación relativamente alta, la mayoría del área REDD+ no lo está. Por lo menos en Indonesia, los proyectos REDD+ de primera generación están ubicados en donde tengan probabilidad de entregar beneficios para la biodiversidad. Sin embargo, si se espera que REDD+ entregue beneficios adicionales para el clima y la biodiversidad, los proyectos necesitarán enfocarse en los bosques con la mayor amenaza de deforestación, lo que tendrá implicaciones de costo para la implementación futura de REDD+. PMID:25864538

  11. Nuevos fenómenos en erupciones cometarias

    NASA Astrophysics Data System (ADS)

    Silva, A.

    Se discuten aquí tres procesos físicos novedosos encontrados en la actividad de cometas: 1) El rol de una distribución de granos de hielo como fuente extendida de H2O en la coma, 2) El efecto de una discontinuidad en el plasma cometario, llamada Cometopausa, sobre la excitación del radical OH , y 3) La actividad por erupciones a grandes distancias heliocéntricas (r > 5 AU). Con respecto a 1) y 2), se presentan modelos que ajustan bien con las observaciones. En cuanto a 3), se presentan explicaciones posibles al fenómeno, y se trata el interesante caso de Chirón 2060, basándose en observaciones propias tomadas desde el CASLEO y datos anteriores.

  12. Fotometría CCD en el campo del cúmulo abierto Ruprecht 58

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Vázquez, R. A.; Seggewiss, W.; Ostrov, P.; Solivella, G. R.

    La región de Vela-Puppis contiene varios cúmulos cuyo estudio puede brindarnos información acerca de la cinemática y el estado evolutivo de la población estelar en las zonas externas del disco galáctico. A través de observaciones CCD en los filtros UBV en el campo del cúmulo abierto Ruprecht 58 (α2000= 8h 14m 41s, δ2000=-31o 57'), se han determinado por primera vez los parámetros fundamentales de este cúmulo tales como distancia, enrojecimiento y edad. Se analiza también la estructura de su secuencia principal y la presencia de gigantes y binarias.

  13. Formación estelar y AGNs en los entornos de quasars

    NASA Astrophysics Data System (ADS)

    Coldwell, G.; García Lambas, D.

    En este trabajo utilizamos las galaxias del catálogo 2dF (2dF public 100K data release) y muestras de quasars tomados del catálogo Verón-Cetty & Verón (2001) para estudiar la naturaleza de estas galaxias en los entornos de quasars con redshift en el rango 0.1< z < 0.2. Estudiamos la distribución de índices espectrales, η, de galaxias a distintas distancias proyectadas de quasars y con diferencias de velocidad radial Δ V <= 500 km s-1. Por comparación, realizamos el mismo análisis en una muestra de galaxias random del catálogo 2dF y en una muestra de cúmulos Abell con similar distribución de redshift que los quasars. Los resultados indican que existe una gran fracción de galaxias con fuertes líneas de emisión, eta > 3.5, en los entornos de quasars comparado con la fracción presente en las vecindades de galaxias típicas del 2dF. Analizamos las distribuciones de luminosidad para estas galaxias (eta > 3.5) encontrando un exceso de galaxias mas luminosas que M ˜ -19.5 en las vecindades de quasars, indicativo de la posible presencia de AGNs. Por otro lado, estimamos la tasa de formación estelar promedio para objetos a distintas distancias de quasars, galaxias y cúmulos de galaxias detectando una actividad de formacion estelar significativamente alta dentro de 1.5 Mpc h-1 de quasars con respecto a las galaxias del 2dF. Estos resultados proveen evidencia de un particular entorno de galaxias alrededor de Quasars.

  14. There's No Such Thing as a One-Celled Plant or Animal.

    ERIC Educational Resources Information Center

    Kaveski, Sharon; And Others

    1983-01-01

    Considers the classification of organisms into five kingdoms based on evidence from molecular biology and microscopic techniques. Divides organisms into Protoctista, Monera, Fungi, Plantae, and Animalia, discussing characteristics of prokaryotes and eukaryotes as related to division of the kingdoms--prokaryotes in kingdom Monera and eukaryotes in

  15. Extracellular Genomic DNA Mediates Enhancement of Xylella fastidiosa Biofilm Formation in Vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xylella fastidiosa (Xf) produces extracellular DNA in PD3 liquid medium. This extracellular DNA could enhance biofilm formation, a factor in successful establishment of Xf in planta. The relative amounts of extracellular DNA were positively correlated with planktonic growth and biofilm formation in ...

  16. Draft Genome Sequence of Burkholderia cenocepacia Strain 869T2, a Plant-Beneficial Endophytic Bacterium.

    PubMed

    Ho, Ying-Ning; Huang, Chieh-Chen

    2015-01-01

    An endophytic bacterium, Burkholderia cenocepacia 869T2, isolated from vetiver grass, has shown its abilities for both in planta biocontrol and plant growth promotion. Its draft genome sequence was determined to provide insights into those metabolic pathways involved in plant-beneficial activity. This is the first genome report for endophytic B. cenocepacia. PMID:26564046

  17. Infection of Helicoverpa armigera by endophytic Beauveria bassiana colonizing tomato plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel endophytic strain of Beauveria bassiana was isolated from leaf tissue of a wild tomato plant. This strain and two B. bassiana strains previously isolated from soil were evaluated for their ability to endophytically colonize tomatoes and subsequent in planta efficacy against Helicoverpa armig...

  18. Characterizing resistance to infection by the root pathogen Armillaria mellea in tolerant and susceptible grapevine rootstocks.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapevine rootstocks that are resistant to the basidiomycete fungus Armillaria mellea have not been identified, mainly due to lack of a rapid and reliable inoculation technique. The aim of our research was to develop an in planta assay for inoculating grapevines and tracking root infection. We pro...

  19. Functional, structural and phylogenetic analysis of domains underlying the Al-sensitivity of the aluminium-activated malate/anion transporter, TaALMT1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    TaALMT1 (Triticum aestivum Aluminum Activated Malate Transporter) is the founding member of a novel gene family of anion transporters (ALMTs) that mediate the efflux of organic acids. A small subgroup of root-localized ALMTs, including TaALMT1, is physiologically associated with in planta aluminum (...

  20. Genome Plasticity in the Genus Mycosphaerella

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most members of the genus Mycosphaerella grow very slowly in culture and have long latent periods in planta. Until recently, very little was known about their genetics or host-pathogen interactions. Genomes of two species have been sequenced: the septoria tritici blotch pathogen of wheat, M. grami...

  1. Comparison of Ergot Alkaloid Biosynthesis Gene Clusters in Claviceps Species Indicates Loss of Late Pathway Steps in Evolution of C. fusiformis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The grass parasites Claviceps purpurea and Claviceps fusiformis produce ergot alkaloids (EA) in planta and in submerged culture. Whereas EA synthesis (EAS) in C. purpurea proceeds via clavine intermediates to lysergic acid and the complex ergopeptines, C. fusiformis produces only agroclavine and ely...

  2. Identification of microdomains involved in association of "Arabidopsis" Ca(2+)/H(+) exchangers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In planta, high capacity tonoplast Ca2+/H+ antiport is mediated in part by a family of CAtion Exchangers (CAX). Each CAX can be divided into two weakly homologous halves (N- and C-) at the negatively charged loop between transmembrane (TM) 6 and TM7. Some CAX halves (N+C) co-expressed in yeast cells...

  3. Molecular characterization of an endornavirus from Cucumis spp

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endornaviruses infect hosts in the kingdoms Plantae, Fungi and Chromista. They are efficiently transmitted vertically and generally do not induce visible symptoms. In this investigation high molecular weight dsRNA, representing the genome of an endornavirus, was isolated from an unknown melon (Cucum...

  4. Maize seedling blight induced by Fusarium verticillioides: accumulation of fumonisin B1 in leaves without colonization of the leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides produces fumonisin mycotoxins during the colonization of maize, and fumonisin B1 (FB1) production is necessary for manifestation of maize seedling blight disease. The objective of this study was to assess the in planta occurrence of fumonisin, fungal colonization, and disea...

  5. Chemical inhibition of potato ABA 8'-hydroxylase activity alters in vitro and in vivo ABA metabolism and endogenous ABA levels but does not affect potato microtuber dormancy duration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of azole-type P450 inhibitors and two metabolism-resistant ABA analogs on in vitro ABA 8'-hydroxylase activity, in planta ABA metabolism, endogenous ABA content, and tuber meristem dormancy duration were examined in potato (Solanum tuberosum L. cv. Russet Burbank). When functionally expr...

  6. Chemical inhibition of ABA-8'-hydroxylase alters in vivo ABA metabolism, increases endogenous ABA content but does not affect microtuber dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of azole-type P450 inhibitors on in vitro ABA 8'-hydroxylase activity, in planta ABA metabolism, endogenous ABA content, and tuber meristem dormancy duration were examined in potato (Solanum tuberosum L. cv. Russet Burbank). When functionally expressed in yeast, three potato CYP707A gene...

  7. Molecular Characterization of Citrus Tristeza Virus Isolates from Mild Strain Cross Protection Experiments in Peru

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven isolates of Citrus tristeza virus (CTV) collected from the Topara Nursery, Lima, Peru were established as in planta cultures in Madam Vinous sweet orange in the Exotic Citrus Pathogen Quarantine Greenhouse, Beltsville, MD. Two of the isolates were collected from non-cross protected plants; Pe...

  8. The Irish Potato Famine Pathogen Phytophthora infestans Translocates the CRN8 Kinase into Host Plant Cells

    PubMed Central

    van Damme, Mireille; Bozkurt, Tolga O.; Cakir, Cahid; Schornack, Sebastian; Sklenar, Jan; Jones, Alexandra M. E.; Kamoun, Sophien

    2012-01-01

    Phytopathogenic oomycetes, such as Phytophthora infestans, secrete an arsenal of effector proteins that modulate plant innate immunity to enable infection. We describe CRN8, a host-translocated effector of P. infestans that has kinase activity in planta. CRN8 is a modular protein of the CRN effector family. The C-terminus of CRN8 localizes to the host nucleus and triggers cell death when the protein is expressed in planta. Cell death induction by CRN8 is dependent on its localization to the plant nucleus, which requires a functional nuclear localization signal (NLS). The C-terminal sequence of CRN8 has similarity to a serine/threonine RD kinase domain. We demonstrated that CRN8 is a functional RD kinase and that its auto-phosphorylation is dependent on an intact catalytic site. Co-immunoprecipitation experiments revealed that CRN8 forms a dimer or multimer. Heterologous expression of CRN8 in planta resulted in enhanced virulence by P. infestans. In contrast, in planta expression of the dominant-negative CRN8R469A;D470A resulted in reduced P. infestans infection, further implicating CRN8 in virulence. Overall, our results indicate that similar to animal parasites, plant pathogens also translocate biochemically active kinase effectors inside host cells. PMID:22927814

  9. The HDF1 histone deacetylase gene is important for conidiation, sexual reproduction, and pathogenesis in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head blight caused by Fusarium graminearum is an important disease of wheat and barley. Its genome contains chromosomal regions with higher genetic variation and enriched for genes expressed in planta, suggesting a role of chromatin modification in the regulation of infection-related genes. In a pre...

  10. Advances in flavanoid glycosyltransferase research: integrating recent findings with long-term citrus studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonoid glycosides are required for a number of crucial roles in planta and have the potential for development in a variety of agricultural, medicinal, and biotechnological applications. A number of recent advancements have been made in characterizing glycosyltransferases, the enzymes that are res...

  11. Aspergillus oryzae NRRL 35191 from coffee, a non-toxigenic endophyte with the ability to synthesize kojic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus oryzae was isolated as an endophyte from coffee leaves and found to produce kojic acid in culture. When inoculated in cacao seedlings (Theobroma cacao L.), A. oryzae grew endophytically and synthesize kojic acid in planta. Cacao seedlings inoculated with A. oryzae produced higher levels...

  12. Cigarrillos de mentol | Smokefree Espaol

    Cancer.gov

    Qu es el mentol? El mentol es una sustancia encontrada naturalmente en las plantas de menta, tales como la menta fresca y la hierbabuena. Deja una sensacin refrescante y se usa frecuentemente para aliviar el dolor y la irritacin leve, y para prevenir infecciones [1].

  13. Cigarrillos de mentol | Smokefree Español

    Cancer.gov

    ¿Qué es el mentol? El mentol es una sustancia encontrada naturalmente en las plantas de menta, tales como la menta fresca y la hierbabuena. Deja una sensación refrescante y se usa frecuentemente para aliviar el dolor y la irritación leve, y para prevenir infecciones [1].

  14. ALGINATE GENE EXPRESSION BY PSEUDOMONAS SYRINGAE PV. TOMATO DC3000 IN HOST AND NONHOST PLANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas syringae produces the exopolysaccharide alginate, a copolymer of mannuronic and guluronic acid. Although alginate has been isolated from plants infected by P. syringae, the signals and timing of alginate gene expression in planta have not been described. In this study, an algD::uidA tr...

  15. Variation in the TonB-dependent Outer-Membrane Proteins in Plant-Associated Strains of Pseudomonas fluorescens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient acquisition is key to the ecological fitness of environmental bacteria such as Pseudomonas fluorescens and TonB-dependent outer-membrane proteins are important components of the cellular machinery for the uptake of substrates from the environment. Genomic sequences of ten strains of plant-a...

  16. SITE-SPECIFIC RECOMBINATION FOR PLANT GENETIC ENGINEERING: STRATEGY FOR AGRO-MEDIATED GENE STACKING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The precise rearrangement of DNA in planta can be achieved through site-specific recombination. For the past decade and a half, laboratory experiments have shown that site-specific recombination can delete genomic DNA, regulate gene expression, recombine chromosomes, and target new DNA into designat...

  17. The parA resolvase performs site-specific genomic excision in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have designed a site-specific excision detection system in Arabidopsis to study the in planta activity of the small serine recombinase ParA. Using a transient expression assay as well as stable transgenic plant lines, we show that the ParA recombinase is catalytically active and capable of perfo...

  18. Transformation of Bacillus mojavensis with GFP and its endophytic localization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current studies on the use of bacterial endophytes for disease control and mycotoxin reduction in maize require the in planta localization and interaction of the intended biocontrol agent. Bacillus mojavensis, an endophytic species that has a phenotypic similarity to B. subtilis, has the potential...

  19. There's No Such Thing as a One-Celled Plant or Animal.

    ERIC Educational Resources Information Center

    Kaveski, Sharon; And Others

    1983-01-01

    Considers the classification of organisms into five kingdoms based on evidence from molecular biology and microscopic techniques. Divides organisms into Protoctista, Monera, Fungi, Plantae, and Animalia, discussing characteristics of prokaryotes and eukaryotes as related to division of the kingdoms--prokaryotes in kingdom Monera and eukaryotes in…

  20. Cell-cell signalling promotes ferric iron uptake in Xanthomonas oryzae pv. oryzicola that contribute to its virulence and growth inside rice.

    PubMed

    Rai, Rikky; Javvadi, Sreegowrinadh; Chatterjee, Subhadeep

    2015-05-01

    Cell-cell communication mediated by diffusible signal factor (DSF) plays an important role in virulence of several Xanthomonas group of plant pathogens. In the bacterial pathogen of rice, Xanthomonas oryzae pv. oryzicola, DSF is required for virulence and in planta growth. In order to understand the role of DSF in promoting in planta growth and virulence, we have characterized the DSF deficient mutant of X. oryzae pv. oryzicola. Mutant analysis by expression analysis, radiolabelled iron uptake studies and growth under low-iron conditions indicated that DSF positively regulates ferric iron uptake. Further, the DSF deficient mutant of X. oryzae pv. oryzicola exhibited a reduced capacity to use ferric form of iron for growth under low-iron conditions. Exogenous iron supplementation in the rice leaves rescued the in planta growth deficiency of the DSF deficient mutant. These data suggest that DSF promotes in planta growth of X. oryzae pv. oryzicola by positively regulating functions involved in ferric iron uptake which is important for its virulence. Our results also indicate that requirement of iron uptake strategies to utilize either Fe(3+) or Fe(2+) form of iron for colonization may vary substantially among closely related members of the Xanthomonas group of plant pathogens. PMID:25656587

  1. Herbarium of the University of Malaga (Spain): Vascular Plants Collection

    PubMed Central

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    Abstract The herbarium of University of Málaga (MGC Herbarium) is formed by four biological collections. The vascular plants collection (MGC-Cormof) is the main collection of the herbarium. MGC-Cormof dataset aims to digitize and publish data associated with over 76.000 specimens deposited in the collection, of which 97.2% of the specimens are identified at species level. Since 2011, the University of Malaga’s Central Research Service (SCAI) has been responsible for maintaining the herbariums and the dataset. The collection is growing continuously, with an annual intake of about 1.500 specimens. Nearly 96% of the collection is digitized, by Herbar v3.7.1 software (F. Pando et al. 1996–2011), making over 73.000 specimens accessible through the GBIF network (http://data.gbif.org/datasets/resource/8105/). At present, 247 families and 8.110 taxa, distributed in angiosperms (93.97%), ferns and fern allies (4.89%) and gymnosperms (1.14%), constitute the MGC-Cormof collection. The families and genera best represented in the collection are Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria and Quercus. Most of the specimens are from the Western Mediterranean Region, fundamentally Southern Spain (Andalusia: 82% of specimens) and Northern Morocco (2.17%). Approximately, 63% of the specimens are georeferenced. The identification of the specimens in the collection has been carried out by the plant biology department at the University of Malaga and plus 40% of the specimens has been reviewed by experts. The MGC-Cormof dataset has been revised by DarwinTest v3.2 tool (Ortega-Maqueda and Pando 2008) before being published in GBIF. The data included in this database are important for conservation works, taxonomy, flora, cartography, phenology, palynology, among others. El Herbario de la Universidad de Málaga (Herbario MGC) está constituido por cuatro colecciones biológicas. La colección de plantas vasculares (MGC Cormof) es la colección principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996–2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  2. Herbarium of the university of malaga (Spain): vascular plants collection.

    PubMed

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    The herbarium of University of Málaga (MGC Herbarium) is formed by four biological collections. The vascular plants collection (MGC-Cormof) is the main collection of the herbarium. MGC-Cormof dataset aims to digitize and publish data associated with over 76.000 specimens deposited in the collection, of which 97.2% of the specimens are identified at species level. Since 2011, the University of Malaga's Central Research Service (SCAI) has been responsible for maintaining the herbariums and the dataset. The collection is growing continuously, with an annual intake of about 1.500 specimens. Nearly 96% of the collection is digitized, by Herbar v3.7.1 software (F. Pando et al. 1996-2011), making over 73.000 specimens accessible through the GBIF network (http://data.gbif.org/datasets/resource/8105/). At present, 247 families and 8.110 taxa, distributed in angiosperms (93.97%), ferns and fern allies (4.89%) and gymnosperms (1.14%), constitute the MGC-Cormof collection. The families and genera best represented in the collection are Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria and Quercus. Most of the specimens are from the Western Mediterranean Region, fundamentally Southern Spain (Andalusia: 82% of specimens) and Northern Morocco (2.17%). Approximately, 63% of the specimens are georeferenced. The identification of the specimens in the collection has been carried out by the plant biology department at the University of Malaga and plus 40% of the specimens has been reviewed by experts. The MGC-Cormof dataset has been revised by DarwinTest v3.2 tool (Ortega-Maqueda and Pando 2008) before being published in GBIF. The data included in this database are important for conservation works, taxonomy, flora, cartography, phenology, palynology, among others. El Herbario de la Universidad de Málaga (Herbario MGC) está constituido por cuatro colecciones biológicas. La colección de plantas vasculares (MGC Cormof) es la colección principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996-2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  3. Algal endosymbionts as vectors of horizontal gene transfer in photosynthetic eukaryotes.

    PubMed

    Qiu, Huan; Yoon, Hwan Su; Bhattacharya, Debashish

    2013-01-01

    Photosynthesis in eukaryotes occurs in the plastid, an organelle that is derived from a single cyanobacterial primary endosymbiosis in the common ancestor of the supergroup Plantae (or Archaeplastida) that includes green, red, and glaucophyte algae and plants. However a variety of other phytoplankton such as the chlorophyll c-containing diatoms, dinoflagellates, and haptophytes contain a red alga-derived plastid that traces its origin to secondary or tertiary (eukaryote engulfs eukaryote) endosymbiosis. The hypothesis of Plantae monophyly has only recently been substantiated, however the extent and role of endosymbiotic and horizontal gene transfer (EGT and HGT) in algal genome evolution still remain to be fully understood. What is becoming clear from analysis of complete genome data is that algal gene complements can no longer be considered essentially eukaryotic in provenance; i.e., with the expected addition of several hundred cyanobacterial genes derived from EGT and a similar number derived from the mitochondrial ancestor. For example, we now know that foreign cells such as Chlamydiae and other prokaryotes have made significant contributions to plastid functions in Plantae. Perhaps more surprising is the recent finding of extensive bacterium-derived HGT in the nuclear genome of the unicellular red alga Porphyridium purpureum that does not relate to plastid functions. These non-endosymbiont gene transfers not only shaped the evolutionary history of Plantae but also were propagated via secondary endosymbiosis to a multitude of other phytoplankton. Here we discuss the idea that Plantae (in particular red algae) are one of the major players in eukaryote genome evolution by virtue of their ability to act as "sinks" and "sources" of foreign genes through HGT and endosymbiosis, respectively. This hypothesis recognizes the often under-appreciated Rhodophyta as major sources of genetic novelty among photosynthetic eukaryotes. PMID:24065973

  4. Algal endosymbionts as vectors of horizontal gene transfer in photosynthetic eukaryotes

    PubMed Central

    Qiu, Huan; Yoon, Hwan Su; Bhattacharya, Debashish

    2013-01-01

    Photosynthesis in eukaryotes occurs in the plastid, an organelle that is derived from a single cyanobacterial primary endosymbiosis in the common ancestor of the supergroup Plantae (or Archaeplastida) that includes green, red, and glaucophyte algae and plants. However a variety of other phytoplankton such as the chlorophyll c-containing diatoms, dinoflagellates, and haptophytes contain a red alga-derived plastid that traces its origin to secondary or tertiary (eukaryote engulfs eukaryote) endosymbiosis. The hypothesis of Plantae monophyly has only recently been substantiated, however the extent and role of endosymbiotic and horizontal gene transfer (EGT and HGT) in algal genome evolution still remain to be fully understood. What is becoming clear from analysis of complete genome data is that algal gene complements can no longer be considered essentially eukaryotic in provenance; i.e., with the expected addition of several hundred cyanobacterial genes derived from EGT and a similar number derived from the mitochondrial ancestor. For example, we now know that foreign cells such as Chlamydiae and other prokaryotes have made significant contributions to plastid functions in Plantae. Perhaps more surprising is the recent finding of extensive bacterium-derived HGT in the nuclear genome of the unicellular red alga Porphyridium purpureum that does not relate to plastid functions. These non-endosymbiont gene transfers not only shaped the evolutionary history of Plantae but also were propagated via secondary endosymbiosis to a multitude of other phytoplankton. Here we discuss the idea that Plantae (in particular red algae) are one of the major players in eukaryote genome evolution by virtue of their ability to act as “sinks” and “sources” of foreign genes through HGT and endosymbiosis, respectively. This hypothesis recognizes the often under-appreciated Rhodophyta as major sources of genetic novelty among photosynthetic eukaryotes. PMID:24065973

  5. Auxin and cytokinin control formation of the quiescent centre in the adventitious root apex of arabidopsis

    PubMed Central

    Della Rovere, F.; Fattorini, L.; D'Angeli, S.; Veloccia, A.; Falasca, G.; Altamura, M. M.

    2013-01-01

    Background and Aims Adventitious roots (ARs) are part of the root system in numerous plants, and are required for successful micropropagation. In the Arabidopsis thaliana primary root (PR) and lateral roots (LRs), the quiescent centre (QC) in the stem cell niche of the meristem controls apical growth with the involvement of auxin and cytokinin. In arabidopsis, ARs emerge in planta from the hypocotyl pericycle, and from different tissues in in vitro cultured explants, e.g. from the stem endodermis in thin cell layer (TCL) explants. The aim of this study was to investigate the establishment and maintenance of the QC in arabidopsis ARs, in planta and in TCL explants, because information about this process is still lacking, and it has potential use for biotechnological applications. Methods Expression of PR/LR QC markers and auxin influx (LAX3)/efflux (PIN1) genes was investigated in the presence/absence of exogenous auxin and cytokinin. Auxin was monitored by the DR5::GUS system and cytokinin by immunolocalization. The expression of the auxin-biosynthetic YUCCA6 gene was also investigated by in situ hybridization in planta and in AR-forming TCLs from the indole acetic acid (IAA)-overproducing superroot2-1 mutant and its wild type. Key Results The accumulation of auxin and the expression of the QC marker WOX5 characterized the early derivatives of the AR founder cells, in planta and in in vitro cultured TCLs. By determination of PIN1 auxin efflux carrier and LAX3 auxin influx carrier activities, an auxin maximum was determined to occur at the AR tip, to which WOX5 expression was restricted, establishing the positioning of the QC. Cytokinin caused a restriction of LAX3 and PIN1 expression domains, and concomitantly the auxin biosynthesis YUCCA6 gene was expressed in the apex. Conclusions In ARs formed in planta and TCLs, the QC is established in a similar way, and auxin transport and biosynthesis are involved through cytokinin tuning. PMID:24061489

  6. Three-dimensional mathematical model to simulate groundwater flow in the lower Palar River basin, southern India

    NASA Astrophysics Data System (ADS)

    Senthilkumar, M.; Elango, L.

    A three-dimensional mathematical model to simulate regional groundwater flow was used in the lower Palar River basin, in southern India. The study area is characterised by heavy ion of groundwater for agricultural, industrial and drinking water supplies. There are three major pumping stations on the riverbed apart from a number of wells distributed over the area. The model simulates groundwater flow over an area of about 392 km2 with 70 rows, 40 columns, and two layers. The model simulated a transient-state condition for the period 1991-2001. The model was calibrated for steady- and transient-state conditions. There was a reasonable match between the computed and observed heads. The transient model was run until the year 2010 to forecast groundwater flow under various scenarios of overpumping and less recharge. Based on the modelling results, it is shown that the aquifer system is stable at the present rate of pumping, excepting for a few locations along the coast where the groundwater head drops from 0.4 to 1.81 m below sea level during the dry seasons. Further, there was a decline in the groundwater head by 0.9 to 2.4 m below sea level in the eastern part of the area when the aquifer system was subjected to an additional groundwater withdrawal of 2 million gallons per day (MGD) at a major pumping station. Les modèles mathématiques en trois dimensions de l'écoulement souterrain régional sont très utiles pour la gestion des ressources en eau souterraine, car ils permettent une évaluation des composantes des processus hydrologiques et fournissent une description physique de l'écoulement de l'eau dans un aquifère. Une telle modélisation a été entreprise sur une partie du bassin inférieur de la rivière Palar, dans le sud de l'Inde. La zone d'étude est caractérisée par des prélèvements importants d'eau souterraine pour l'agriculture, l'industrie et l'eau potable. Il existe trois grandes stations de pompage sur la rivière en plus d'un certain nombre de puits répartis dans cette région. Le modèle simule l'écoulement souterrain dans une région d'environ 392 km2 avec 70 rangs, 40 colonnes et deux couches. Le modèle a fonctionné en régime transitoire en utilisant une approximation aux différences finies d'une équation différentielle partielle en trois dimensions de l'écoulement souterrain dans cet aquifère pour la période 1991-2001. Le modèle a été calibré pour des conditions de régime permanent et transitoire. Les charges hydrauliques calculées étaient en bon accord avec celles observées. Sur la base des résultats du modèle, il est apparu que le système aquifère est stable pour ce taux de pompage, excepté en quelques sites le long de la côte où l'eau marine a pénétré 50-100 m dans les terres. Le modèle transitoire a tourné jusqu'en 2010 afin de prévoir l'écoulement souterrain dynamique pour différents scénarios de pompage excessif et de recharge réduite. Il se produit un abaissement de la piézométrie de la nappe de 0.6 à 0.8 m dans la partie orientale, alors que l'aquifère est soumis à un prélèvement supplémentaire de 8,000 m3/jour à l'une des stations principales de pompage. Même avec le niveau actuel de pompage, la piézométrie de la nappe descendrait sous le niveau de la mer au cours des saisons sèches. Le modèle prédit le fonctionnement du système aquifère sous différentes conditions de stress hydrologique. Los modelos tridimensionales de flujo de aguas subterráneas son útiles para gestionar los recursos hídricos subterráneos, ya que proporcionan una aproximación a los diversos procesos hidrológicos y una descripción cuantitativa del flujo de agua en el acuífero. Se ha desarrollado un estudio de modelación de este tipo en una parte de la cuenca baja del río Palar, en el Sur de la India. Esta zona se caracteriza por las intensas extracciones de aguas subterráneas para usos agrícolas, industriales y domésticos. Hay tres estaciones de bombeo principales en el río, además de numerosos pozos distribuidos por la zona. El modelo simula el flujo de las aguas subterráneas en una superficie de 392 km2 por medio de 70 filas, 40 columnas y 2 capas. El modelo ha sido empleado en condiciones transitorias, por medio de la aproximación en diferencias finitas de las ecuaciones diferenciales parciales en tres dimensiones del flujo en el acuífero durante el período 1991-2001. Se ha calibrado el modelo en condiciones permanentes y transitorias. El ajuste entre los niveles calculados y medidos es razonable. A partir de los resultados de la modelación, se ha obtenido que el sistema acuífero es estable con la tasa de bombeo utilizada, exceptuando unos pocos emplazamientos a lo largo de la costa, donde se ha dado lugar a fenómenos de intrusión marina en una distancia de 50-100 m. El modelo transitorio ha sido ejecutado hasta el año 2010 para predecir el flujo dinámico bajo diversos escenarios de sobreexplotación y de reducción de la recarga. Se produce una disminución en los niveles piezométricos de 0.6 a 0.8 m en la zona oriental, donde el sistema acuífero está sometido a una extracción adicional de 2 millones de galones por día en la estación principal de bombeo. Incluso con las extracciones actuales, los niveles piezométricos se sitúan bajo el nivel del mar durante las épocas secas. El modelo predice el comportamiento de este sistema acuífero bajo varias condiciones de presión hidrológica.

  7. Restriction des communications entre l'Atlantique et la Méditerranée au Messinien : apport de la téphrochronologie dans la plate-forme carbonatée et le bassin de Melilla Nador (Rif nord-oriental, Maroc)Restriction of the seawater exchanges between the Atlantic and the Mediterranean during the Messinian: contribution of the tephrochronology of the Melilla Nador area (north-eastern Rif, Morocco)

    NASA Astrophysics Data System (ADS)

    Münch, Philippe; Roger, Stephan; Cornée, Jean-Jacques; Saint Martin, Jean-Paul; Féraud, Gilbert; Moussa, Abdelkhalak Ben

    2001-05-01

    Thirty-eight volcanic layers have been found, from the littoral carbonate platform to the basin, interbedded within the Neogene deposits of the Melilla-Nador area. Ten of them, whose stratigraphic location and geographic extension have been established, were petrographically and mineralogically studied. They have been used as markers to establish an overall platform/basin correlation sketch. Together with these correlations and a synthesis of available ages, we show that the sedimentation areas, and thus the oceanic circulations, progressively restricted in this region between 6.5 and 5.77 Ma as a consequence of tectono-magmatic activity of the Gourougou magmatic field.

  8. Establishment of Lipolexis oregmae (Hymenoptera: Aphidiidae) in a classical biological control program directed against the brown citrus aphid (Homoptera: Aphididae) in Florida

    SciTech Connect

    Persad, A.B.; Hoy, M.A.; Ru Nguyen

    2007-03-15

    The parasitoid Lipolexis oregmae Gahan (introduced as L. scutellaris Mackauer) was imported from Guam, evaluated in quarantine, mass reared, and released into citrus groves in Florida in a classical biological control program directed against the brown citrus aphid, Toxoptera citricida Kirkaldy. Releases of 20,200, 12,100, and 1,260 adults of L. oregmae were made throughout Florida during 2000, 2001, and 2002, respectively. To determine if L. oregmae had successfully established, surveys were conducted throughout the state beginning in the summer of 2001 and continuing through the summer of 2003. Parasitism during 2001 and 2002 was evaluated by holding brown citrus aphids in the laboratory until parasitoid adults emerged. Lipolexis oregmae was found in 10 sites in 7 counties and 4 sites in 3 counties with parasitism rates ranging from 0.7 to 3.3% in 2001 and 2002, respectively. Laboratory tests indicated that high rates of mortality occurred if field-collected parasitized aphids were held in plastic bags, so a molecular assay was used that allowed immature L. oregmae to be detected within aphid hosts immediately after collection. The molecular assay was used in 2003 with the brown citrus aphids and with other aphid species collected from citrus, weeds, and vegetables near former release sites; immatures of L. oregmae were detected in black citrus aphids, cowpea aphids, spirea aphids, and melon aphids, as well as in the brown citrus aphid, in 4 of 8 counties sampled, with parasitism ranging from 2.0 to 12.9%, indicating that L. oregmae is established and widely distributed. Samples taken in Polk County during Oct 2005 indicated that L. oregmae has persisted. The ability of L. oregmae to parasitize other aphid species on citrus, and aphids on other host plants, enhances the ability of L. oregmae to persist when brown citrus aphid populations are low. (author) [Spanish] El parasitoide Lipolexis oregmae Gahan (introducido como L. scutellaris Mackauer) fue importado de Guam, evaluado en cuarentena, criado en masa y liberado en huertos de citricos en un programa de control biologico clasico dirigido contra el afido pardo de citricos, Toxoptera citricida Kirkaldy. Se hicieron liberaciones de 20,200, 12,100, y 1,260 adultos de L. oregmae a traves de la Florida durante los anos de 2000, 2001, y 2002, respectivamente. Para determinar si L. oregmae ha logrado en establecer, se realizaron sondeos a traves del estado empezando en el verano del 2001 y continuando hasta el final del verano del 2003. El parasitismo durante 2001 y 2002 fue evaluado con el mantenimiento de individuos del afido pardo de los citricos en el laboratorio hasta que los adultos emergieron. Lipolexis oregmae fue encontrado en 10 sitios en 7 condados y con tasas de parasitismo en 4 sitios en 3 condados entre 0.7 a 3.3% en el 2001 y 2002, respectivamente. Las pruebas del laboratorio indicaron que las tasas altas de mortalidad fueron posibles si los afidos con parasitos recolectados en el campo fueron mantenidos en bolsas plasticas, entonces un ensayo molecular fue usado con lo que permitio la deteccion de inmaduros de L. oregmae dentro de los hospederos de afidos inmediatamente despues de la recoleccion. El ensayo molecular fue usado en el 2003 con individuos del afido pardo de los citricos y con otras especies de afidos recolectados sobre citricos, malezas y hortalizas cerca de los sitios donde los parasitoides fueron liberados anteriormente; inmaduros de L. oregmae fueron detectados en individuos del afido negro de los citricos, el afido del caupi, el afido spirea y el afido del melon, ademas del afido pardo de los citricos en 4 de los 8 condados muestreados, con la tasa del parasitismo entre 2.0 a12.9%, indicando que L. oregmae estaba estabecido y ampliamente distribuido. Las muestras tomadas en el Condado de Polk durante octobre del 2005 indicaron que L. oregmae ha persistido. La capacidad de L. oregmae para parasitar otras especies de afidos sobre citricos y otros afidos sobre otras plantas hospederas, incrementa la capacidad de L. oregmae para persistir cuando las poblaciones del afido pardo de los citricos estan bajas. (author)

  9. Cyanophora paradoxa genome elucidates origin of photosynthesis in algae and plants.

    PubMed

    Price, Dana C; Chan, Cheong Xin; Yoon, Hwan Su; Yang, Eun Chan; Qiu, Huan; Weber, Andreas P M; Schwacke, Rainer; Gross, Jeferson; Blouin, Nicolas A; Lane, Chris; Reyes-Prieto, Adrián; Durnford, Dion G; Neilson, Jonathan A D; Lang, B Franz; Burger, Gertraud; Steiner, Jürgen M; Löffelhardt, Wolfgang; Meuser, Jonathan E; Posewitz, Matthew C; Ball, Steven; Arias, Maria Cecilia; Henrissat, Bernard; Coutinho, Pedro M; Rensing, Stefan A; Symeonidi, Aikaterini; Doddapaneni, Harshavardhan; Green, Beverley R; Rajah, Veeran D; Boore, Jeffrey; Bhattacharya, Debashish

    2012-02-17

    The primary endosymbiotic origin of the plastid in eukaryotes more than 1 billion years ago led to the evolution of algae and plants. We analyzed draft genome and transcriptome data from the basally diverging alga Cyanophora paradoxa and provide evidence for a single origin of the primary plastid in the eukaryote supergroup Plantae. C. paradoxa retains ancestral features of starch biosynthesis, fermentation, and plastid protein translocation common to plants and algae but lacks typical eukaryotic light-harvesting complex proteins. Traces of an ancient link to parasites such as Chlamydiae were found in the genomes of C. paradoxa and other Plantae. Apparently, Chlamydia-like bacteria donated genes that allow export of photosynthate from the plastid and its polymerization into storage polysaccharide in the cytosol. PMID:22344442

  10. Carnosic acid.

    PubMed

    Birtić, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc

    2015-07-01

    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (∼70 years ago) and its identification (∼50 years ago), numerous articles and patents (∼400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. PMID:25639596

  11. Protein fragment bimolecular fluorescence complementation analyses for the in vivo study of protein-protein interactions and cellular protein complex localizations

    PubMed Central

    Waadt, Rainer; Schlücking, Kathrin; Schroeder, Julian I.; Kudla, Jörg

    2014-01-01

    Summary The analyses of protein-protein interactions is crucial for understanding cellular processes including signal transduction, protein trafficking and movement. Protein fragment complementation assays are based on the reconstitution of protein function when non-active protein fragments are brought together by interacting proteins that were genetically fused to these protein fragments. Bimolecular fluorescence complementation (BiFC) relies on the reconstitution of fluorescent proteins and enables both the analysis of protein-protein interactions and the visualization of protein complex formations in vivo. Transient expression of proteins is a convenient approach to study protein functions in planta or in other organisms, and minimizes the need for time-consuming generation of stably expressing transgenic organisms. Here we describe protocols for BiFC analyses in Nicotiana benthamiana and Arabidopsis thaliana leaves transiently transformed by Agrobacterium infiltration. Further we discuss different BiFC applications and provide examples for proper BiFC analyses in planta. PMID:24057390

  12. The ybiT Gene of Erwinia chrysanthemi Codes for a Putative ABC Transporter and Is Involved in Competitiveness against Endophytic Bacteria during Infection

    PubMed Central

    Llama-Palacios, Arancha; López-Solanilla, Emilia; Rodríguez-Palenzuela, Pablo

    2002-01-01

    We investigated the role in bacterial infection of a putative ABC transporter, designated ybiT, of Erwinia chrysanthemi AC4150. The deduced sequence of this gene showed amino acid sequence similarity with other putative ABC transporters of gram-negative bacteria, such as Escherichia coli and Pseudomonas aeruginosa, as well as structural similarity with proteins of Streptomyces spp. involved in resistance to macrolide antibiotics. The gene contiguous to ybiT, designated as pab (putative antibiotic biosynthesis) showed sequence similarity with Pseudomonas and Streptomyces genes involved in the biosynthesis of antibiotics. A ybiT mutant (BT117) was constructed by marker exchange. It retained full virulence in potato tubers and chicory leaves, but it showed reduced ability to compete in planta against the wild-type strain or against selected saprophytic bacteria. These results indicate that the ybiT gene plays a role in the in planta fitness of the bacteria. PMID:11916677

  13. A new type of relief condenser for the study of microorganisms.

    PubMed

    Zizka, Z

    2009-09-01

    A new type of relief condenser mounted on a current laboratory microscope produced by Lambda Praha was used for the study of microorganisms of two kingdoms, Chromista and Plantae. The pictures obtained by the use of this device had a better resolving power and remarkable contrast, and a well visible 3D effect. Because of the absence of an aperture diaphragm the use was much simpler, compared to relief condensers whose construction was different. PMID:19937221

  14. RT-PCR DETECTION OF CITRUS LEPROSIS VIRUS IN SHRUBS AND WEED PLANTS INFECTED THROUGH Brevipalpus phoenicis (ACARI: TENUIPALPIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    No Brasil são gastos anualmente cerca de US$ 80 milhões para controle de Brevipalpus phoenicis, vetor do vírus leprose dos citros (CiLV). Este ácaro possui comportamento polífago e cosmopolita, presente em inúmeras espécies de plantas junto aos pomares cítricos. Neste trabalho foi investigada a poss...

  15. Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses

    PubMed Central

    2011-01-01

    Background Rice blast is the most threatening disease to cultivated rice. Magnaporthe oryzae, its causal agent, is likely to encounter environmental challenges during invasive growth in its host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that gene expression patterns during in planta invasive growth are similar to in vitro stress conditions, such as nutrient limitation, temperature up shift and oxidative stress, and determined which condition most closely mimicked that of in planta invasive growth. Gene expression data were collected from these in vitro experiments and compared to fungal gene expression during the invasive growth phase at 72 hours post-inoculation in compatible interactions on two grass hosts, rice and barley. Results We identified 4,973 genes that were differentially expressed in at least one of the in planta and in vitro stress conditions when compared to fungal mycelia grown in complete medium, which was used as reference. From those genes, 1,909 showed similar expression patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which in planta conditions closely grouped with the nutrient starvation conditions. Out of these 1,909 genes, 55 genes and 129 genes were induced and repressed in all treatments, respectively. Functional categorization of the 55 induced genes revealed that most were either related to carbon metabolism, membrane proteins, or were involved in oxidoreduction reactions. The 129 repressed genes showed putative roles in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport. Conclusions These findings suggest that M. oryzae is likely primarily coping with nutrient-limited environments at the invasive growth stage 72 hours post-inoculation, and not with oxidative or temperature stresses. PMID:21247492

  16. Biosynthesis of the antimetabolite 6-thioguanine in Erwinia amylovora plays a key role in fire blight pathogenesis.

    PubMed

    Coyne, Sébastien; Chizzali, Cornelia; Khalil, Mohammed N A; Litomska, Agnieszka; Richter, Klaus; Beerhues, Ludger; Hertweck, Christian

    2013-09-27

    Sulfur for fire: The molecular basis for the biosynthesis of the antimetabolite 6-thioguanine (6TG) was unveiled in Erwinia amylovora, the causative agent of fire blight. Bioinformatics, heterologous pathway reconstitution in E. coli, and mutational analyses indicate that the protein YcfA mediates guanine thionation in analogy to 2-thiouridylase. Assays in planta and in cell cultures reveal for the first time a crucial role of 6TG in fire blight pathogenesis. PMID:24038828

  17. Plant and animal glycolate oxidases have a common eukaryotic ancestor and convergently duplicated to evolve long-chain 2-hydroxy acid oxidases.

    PubMed

    Esser, Christian; Kuhn, Anke; Groth, Georg; Lercher, Martin J; Maurino, Veronica G

    2014-05-01

    Glycolate oxidase (GOX) is a crucial enzyme of plant photorespiration. The encoding gene is thought to have originated from endosymbiotic gene transfer between the eukaryotic host and the cyanobacterial endosymbiont at the base of plantae. However, animals also possess GOX activities. Plant and animal GOX belong to the gene family of (L)-2-hydroxyacid-oxidases ((L)-2-HAOX). We find that all (L)-2-HAOX proteins in animals and archaeplastida go back to one ancestral eukaryotic sequence; the sole exceptions are green algae of the chlorophyta lineage. Chlorophyta replaced the ancestral eukaryotic (L)-2-HAOX with a bacterial ortholog, a lactate oxidase that may have been obtained through the primary endosymbiosis at the base of plantae; independent losses of this gene may explain its absence in other algal lineages (glaucophyta, rhodophyta, and charophyta). We also show that in addition to GOX, plants possess (L)-2-HAOX proteins with different specificities for medium- and long-chain hydroxyacids (lHAOX), likely involved in fatty acid and protein catabolism. Vertebrates possess lHAOX proteins acting on similar substrates as plant lHAOX; however, the existence of GOX and lHAOX subfamilies in both plants and animals is not due to shared ancestry but is the result of convergent evolution in the two most complex eukaryotic lineages. On the basis of targeting sequences and predicted substrate specificities, we conclude that the biological role of plantae (L)-2-HAOX in photorespiration evolved by co-opting an existing peroxisomal protein. PMID:24408912

  18. Paracercomonas kinetid ultrastructure, origins of the body plan of Cercomonadida, and cytoskeleton evolution in Cercozoa.

    PubMed

    Cavalier-Smith, Thomas; Karpov, Sergey A

    2012-01-01

    Serial section reconstruction shows that kinetid ultrastructure in two genetically divergent Paracercomonas (P. virgaria, P. metabolica) is basically similar, differing somewhat from clade A cercomonads. Paracercomonas (Paracercomonadidae fam. n.) have a posterior root (dp1) attached to the posterior centriole, unlike Cercomonadidae (here revised to include only Eocercomonas, Cercomonas, Filomonas gen. n., and Neocercomonas), which belong in clade A (new suborder Cercomonadina) with Cavernomonas (Cavernomonadidae fam. n.). Whether dp1 is serially homologous to anterior root da is unclear. The common ancestor of Cercomonadida probably had five microtubular roots, two fibrillar microtubule-nucleating centres generating microtubular cones, and striated connectors between obtusely angled centrioles. Our new data leave the question of holophyly versus polyphyly of Cercomonadida unresolved, but clarify cercozoan root diversity and homologies. Ventral root vp1 is throughout Cercozoa; vp2 might be restricted to the new superclass Ventrifilosa plus Sarcomonadea. Though cercozoan microtubular arrangements differ substantially from others within the kingdom Chromista, the microtubular root numbering system used for other chromists and Plantae is applicable to them; in doing this we found that the single anterior root of excavates (probably ancestral to Chromista, Plantae and unikonts) and Euglenozoa corresponds with R3 (not R4 as previously thought) of corticate eukaryotes (Chromista plus Plantae). PMID:21839678

  19. Elicitin genes expressed in vitro by certain tobacco isolates of Phytophthora parasitica are down regulated during compatible interactions.

    PubMed

    Colas, V; Conrod, S; Venard, P; Keller, H; Ricci, P; Panabières, F

    2001-03-01

    Phytophthora spp. secrete proteins called elicitins in vitro that can specifically induce hypersensitive response and systemic acquired resistance in tobacco. In Phytophthora parasitica, the causal agent of black shank, most isolates virulent on tobacco are unable to produce elicitins in vitro. Recently, however, a few elicitin-producing P. parasitica strains virulent on tobacco have been isolated. We investigated the potential diversity of elicitin genes in P. parasitica isolates belonging to different genotypes and with various virulence levels toward tobacco as well as elicitin expression pattern in vitro and in planta. Although elicitins are encoded by a multigene family, parAl is the main elicitin gene expressed. This gene is highly conserved among isolates, regardless of the elicitin production and virulence levels toward tobacco. Moreover, we show that elicitin-producing P. parasitica isolates virulent on tobacco down regulate parAl expression during compatible interactions, whichever host plant is tested. Conversely, one elicitin-producing P. parasitica isolate that is pathogenic on tomato and avirulent on tobacco still expresses parAl in the compatible interaction. Therefore, some P. parasitica isolates may evade tobacco recognition by down regulating parA1 in planta. The in planta down regulation of parA1 may constitute a suitable mechanism for P. parasitica to infect tobacco without deleterious consequences for the pathogen. PMID:11277430

  20. Using environmental isotopes in the study of the recharge-discharge mechanisms of the Yarmouk catchment area in Jordan

    NASA Astrophysics Data System (ADS)

    Salameh, Elias

    The recharge sources, the flow mechanisms and discharge areas of the different groundwater bodies underlying the Yarmouk River catchment area in Jordan, have, until now, not been adequately explained, although a wide range of hydrological, hydrogeological, and hydrochemical studies have been done. Along the Jordanian part of the catchment area of the Yarmouk River, groundwater issues from different aquifers with a variety of chemistries and types within the same aquifer and in between the different aquifers. Conventional recharge/discharge mechanisms, water balances and chemical analyses did not adequately explain the chemical variations and the different water types found in the area. Applying environmental isotopic tools combined with their altitude effects due to topographic variations (250-1,300 m a.s.l. within a distance of 20 km), and taking into consideration re-evaporation effects on the isotopic depletion and enrichment of rainwater, has greatly helped in understanding the recharge discharge mechanisms of the different aquifers. Precipitation along the highlands of an average of 600 mm/year is found to be depleted in its isotopic content of δO18 = -7.0 to -7.26 and δD = -32.2 to -33.28, whereas that of the Jordan Valley of 350 mm/year is highly enriched in isotopes with δO18 = -4.06 and δD = -14.5. The groundwater recharged along the highlands is depleted in isotopes (δO18 = -6, δD = -30), groundwater at the intermediate elevations is enriched (δO18 = -5, δD = -23) and that of the Jordan Valley aquifers containing meteoric water is highly enriched (δO18 -3.8, δD = -18). The deep aquifers in the Jordan Valley foothills are depleted in isotopes (δO18 -18 = -6, δD = -30) and resemble those of the highland aquifers. Only through using isotopes as a tool, were the sources of the different groundwater bodies and recharge and discharge mechanisms unambiguously explained. It was found that recharge takes place all over the study area and produces groundwater, which, from the highlands towards the Jordan Valley, shows increasing enrichment in isotopes. The highlands aquifer, with its groundwater depleted in isotopes, becomes confined towards the Jordan Valley; and, due to its confining pressure, leaks water upwards into the overlying aquifers causing their water to become less enriched in isotopes. Water depleted in its isotopic composition also seeps upward to the ground surface at the mountain foothills through faults and fissures. Les zones de recharge, les mécanismes d'écoulement et les zones de décharges des différentes masses d'eau souterraine sous le bassin versant de la rivière Yarmouk en Jordanie, étaient expliquées de manière ambiguë par les seuls outils isotopiques. Le long de la parti Jordanienne du bassin versant de la rivière Yarmouk l'eau souterraine provient de différents aquifères et se distinguent par leur type et leur composition chimique, selon que l'eau provient du même ou des différents aquifères. Les mécanismes conventionnels de recharge et de décharge, bilan hydrologique ne donnaient pas d'explications satisfaisantes concernant les variations chimiques et les différents types d'eau. En appliquant les isotopes environnementaux combinés aux effets de l'altitude sur les variations des teneurs isotopiques (l'altitude varie de 250 à 1,300 m sur une distance de 20 km.) et en prenant en considération les effets de ré-évaporation sur l'appauvrissement et l'enrichissement isotopique des eaux pluviales ont fortement contribués à une meilleure compréhension des mécanismes de recharge des différents aquifères. Les précipitations annuelles sont comprises entre 600 mm dans les zones en altitude et 350 mm dans la vallée de la Jordanie. Les écoulements de l'eau souterraine sont dirigés des zones en altitude vers la vallée de la Jordanie. Les eaux souterraines des zones en altitude sont isotopiquement appauvries (δO18 = -6, δD = -30), les eaux souterraines des zones de moyenne altitude sont enrichies (δO18 = -5, δD = -23) et les eaux de la vallée très enrichies (δO18 -3.8, δD = -18). Les aquifers profonds dans la vallée de la Jordanie sont appauvris (δO18 -18 = -6, δD = -30) et se confondent avec les eaux des zones situées en altitude. En appliquant uniquement les isotopes environnementaux comme des outils de compréhension des phénomènes hydrogéologiques, la source des différentes masses d'eau souterraines, les mécanismes de la recharge et de la décharge pourraient être expliqués de manière ambiguë. Las fuentes de recarga, los mecanismos de flujo y las áreas de descarga de los diferentes cuerpos de agua subterránea que subyacen el área de la cuenca del Río Yarmouk en Jordania, se han explicado de manera no ambigua únicamente mediante la aplicación de los isótopos como herramienta. A lo largo de la parte Jordana del área de la cuenca del Río Yarmouk el agua subterránea emerge de diferentes acuíferos con una variedad de tipos y composiciones, ya sea que provengan del mismo acuífero o de diferentes acuíferos. Los mecanismos convencionales de recarga/descarga, balances hídricos y variaciones químicas no han podido explicar las variaciones químicas y los diferentes tipos de aguas. La aplicación de herramientas de isótopos ambientales combinadas con los efectos de altitud derivados de variaciones topográficas (250 hasta 1,300 m s.n.m. en una distancia de 20 km) y tomando en consideración los efectos de re-evaporación en el empobrecimiento de isótopos y enriquecimiento del agua de lluvia han ayudado fuertemente en el entendimiento de los mecanismos de recarga/descarga de los diferentes acuíferos. La precipitación en el área varía de 600 mm/año, a lo largo de las tierras altas, a 350 mm/año en el área del Valle Jordán. El flujo de agua subterránea ocurre de las tierras altas hacia el Valle Jordán. El agua subterránea de las tierras altas está empobrecida en isótopos (δO18 = -6, δD = -30), el agua subterránea de elevaciones intermedias está enriquecida (δO18 = -5, δD = -23), y el agua de los acuíferos del Valle Jordan contiene agua meteórica que se encuentra altamente enriquecida (δO18 = -3.8, δD = -18). Los acuíferos profundos que se localizan al pie de las tierras altas del Valle Jordán están empobrecidos en isótopos (δO18 = -6, δD = -30) y son similares a los acuíferos de las tierras altas. Solo al aplicar los isótopos ambientales como herramienta pudo explicarse de manera inequívoca las fuentes de los diferentes cuerpos de agua subterránea y los mecanismos de recarga y descarga.

  1. Social identity, passion and well-being in university students, the mediating effect of passion.

    PubMed

    Bernabé, Miguel; Lisbona, Ana; Palací, Francisco José; Martín-Aragón, Maite

    2014-01-01

    Research on positive emotions associated with the performance of an activity, such as work or study, has increased exponentially in recent years. Passion is understood as an attitude and intense emotion in the performance of an activity, and it has shown both positive and negative consequences for well-being. A link between social identity and positive emotions through social category membership has been described. The aim of this work is to study the relationship between social identity, the dimensions of passion and the positive impact on university responses. A quasi-experimental design was used on a sample of 266 university students from different Spanish universities (Universidad Nacional de Educación a Distancia, Universidad Miguel Hernández and Universidad de Alicante). Descriptive analyzes were performed on the study's variables using SPSS 18. Structural equation modeling was carried out with AMOS 18 and the mediational analysis with MODMED macro developed by Preacher, Rucker, and Hayes (2007). The results show that the identity of the studies had an indirect effect on positive responses mediated by passion for the studies (RMSEA = .07; CFI = .97; NFI = .96; TLI = .92). It is observed that the harmonious and obsessive dimensions of passion differ in the mediating effect on happiness and satisfaction with studies. Practical and theoretical implications for well-being are discussed. PMID:26054919

  2. Telescopio Solar en Hα (HASTA)

    NASA Astrophysics Data System (ADS)

    Fernández Borda, R.; Francile, C.; Bagala, G.; Bauer, O.; Haerendel, G.; Rieger, E.; Rovira, M.

    El Telescopio Solar en Hα (Hα Solar Telescope for Argentina (-HASTA-) fue recientemente instalado en la Estación Astronómica de Altura Carlos Ulrrico Cesco (OAFA) en El Leoncito. Este instrumento estudiará la evolución de las fulguraciones solares desde tierra con alta resolución temporal y espacial. HASTA es un telescopio refractor de 110 mm con una distancia focal de 165 cm, un filtro Lyot sintonizable (±1Å) con un ancho de banda de 0.3 Å y una cámara CCD de alta resolución (1280×1024 pixels). Todo el conjunto es controlado en forma remota por una PC, la cual además adquiere datos del Sistema de Posicionamiento Global (GPS) y de la estación meteorológica. Diseñado para detectar fulguraciones, el instrumento trabaja en dos modos (patrullaje y fulguración) con una resolución espacial de 1.5 arcseg por pixel y una resolución temporal de 2 seg. HASTA comenzó a operar en Mayo de 1998 y, junto con otros tres instrumentos solares, que se están instalando o se instalaron, harán de El Leoncito un polo de observación solar importante en el Hemisferio Sur.

  3. Teleconferences and Audiovisual Materials in Earth Science Education

    NASA Astrophysics Data System (ADS)

    Cortina, L. M.

    2007-05-01

    Unidad de Educacion Continua y a Distancia, Universidad Nacional Autonoma de Mexico, Coyoaca 04510 Mexico, MEXICO As stated in the special session description, 21st century undergraduate education has access to resources/experiences that go beyond university classrooms. However in some cases, resources may go largely unused and a number of factors may be cited such as logistic problems, restricted internet and telecommunication service access, miss-information, etc. We present and comment on our efforts and experiences at the National University of Mexico in a new unit dedicated to teleconferences and audio-visual materials. The unit forms part of the geosciences institutes, located in the central UNAM campus and campuses in other States. The use of teleconference in formal graduate and undergraduate education allows teachers and lecturers to distribute course material as in classrooms. Course by teleconference requires learning and student and teacher effort without physical contact, but they have access to multimedia available to support their exhibition. Well selected multimedia material allows the students to identify and recognize digital information to aid understanding natural phenomena integral to Earth Sciences. Cooperation with international partnerships providing access to new materials and experiences and to field practices will greatly add to our efforts. We will present specific examples of the experiences that we have at the Earth Sciences Postgraduate Program of UNAM with the use of technology in the education in geosciences.

  4. Foco Nasmyth para el telescopio 2,15mts. de CASLEO

    NASA Astrophysics Data System (ADS)

    Casagrande, A. R.

    En principio, este proyecto intenta lograr el mayor aprovechamiento posible del instrumental que se dispone, buscando la manera de optimizar y hacer más eficiente el servicio que brinda el CASLEO a la comunidad astronómica. El mismo consiste en utilizar dispositivos ya existentes en el telescopio, y darle una utilidad. Tal es el caso del camino óptico destinado al foco Coude. Si tenemos en cuenta que disponemos de un tercer espejo Coude, con todos sus mecanismos automatizados, (actualmente sin uso), una distancia apropiada del plano focal, el espacio y el lugar físico necesario para instalar un periférico, es posible la habilitación de un foco Nasmyth en el telescopio 2,15mts. El hecho de contar con este nuevo foco, redundará en importantes beneficios. En primer lugar, posibilitará la observación, casi simultánea, con dos instrumentos. Otro aspecto a tener en cuenta, es que disminuirá el frecuente cambio del instrumental periférico, motivo este que degrada su ideal puesta a punto. Por último, también de interés, es de destacar su escaso costo de ejecución.

  5. Dispersión de velocidades en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Muriel, H.; García Lambas, D.; Quintana, H.; Infante, L.

    Se ha estudiado la dinámica de galaxias en cúmulos en base a una muestra de aproximadamente 4000 galaxias con estimas de velocidad radial pertenecientes a 40 cúmulos. Se desarrolló un algoritmo para identificar sub-estructuras del tipo ``grupos de galaxias". Una vez eliminada este tipo de sub-estructura se computaron los perfiles radiales de dispersión de velocidades (VDP) para los 40 cúmulos de galaxias. Dada las características de la muestra, fue posible estimar el VDP hasta grandes distancias del centro del cúmulo llegando en algunos casos hasta 7 Mpc-1. Los resultados indican que el 65% de los cúmulos presentan un VDP plano a grandes radios consistente con el modelo isotermo. Estos resultados son discutidos en el marco de las recientes controversias suscitadas respecto de la dinámica de los cúmulos vía los perfiles de temperaturas de cúmulos derivados de la emisión en rayos-X.

  6. Informe Anual a la Nación sobre el Cáncer de 1975 a 2008: preguntas y respuestas

    Cancer.gov

    Los índices generales de mortalidad por cáncer han seguido disminuyendo desde principios de los noventa entre hombres, mujeres y niños. Los índices de mortalidad disminuyeron en promedio 1,6% por año entre 2004 y 2008.

  7. Vegetable Purée: A Pilot Study to Increase Vegetable Consumption among School Lunch Participants in US Elementary Schools

    ERIC Educational Resources Information Center

    Vale, Angela; Schumacher, Julie Raeder; Cullen, Robert W.; Gam, Hae Jin

    2014-01-01

    Purpose/Objectives: Recent US Department of Agriculture regulations increased the amount and variety of vegetables required for school lunches. Vegetables are the most wasted components of lunch while entrées are selected and consumed by the majority of children. This study examined how adding vegetable purée to an elementary school lunch entrée…

  8. Reductions in entree energy density increase children's vegetable intake and reduce energy intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The energy density (ED; kcal/g) of an entrée influences children's energy intake (EI), but the effect of simultaneously changing both ED and portion size of an entrée on preschool children's EI is unknown. In this within-subject crossover study, 3- to 5-year-old children (30 boys, 31 girls) in a day...

  9. Healing war wounds and perfuming exile: the use of vegetal, animal, and mineral products for perfumes, cosmetics, and skin healing among Sahrawi refugees of Western Sahara

    PubMed Central

    2012-01-01

    Background Over the past decade, there has been growing interest within ethnobiology in the knowledge and practices of migrating people. Within this, scholars have given relatively less attention to displaced people and refugees: to the loss, maintenance, and adaptation of refugees’ ethnobiological knowledge, and to its significance for refugees’ wellbeing. This study focuses on cosmetics and remedies used to heal skin afflictions that are traditionally used by Sahrawi refugees displaced in South Western Algerian refugee camps. Methods The research methods included a structured survey carried out with 37 refugee households, semi-structured interviews with 77 refugees, 24 retrospective interviews with refugees and other knowledgeable informants, and a voucher specimen collection of the plants and products cited. Results We recorded the use of 55 plant species, nine animal species, and six mineral products used within the three main use categories discussed in this paper: 1) Remedies for health issues that are typical of the desert environment where the Sahrawi once lived as nomads and now live as refugees (e.g. eye afflictions); 2) Remedies for wounds that are influenced by the Sahrawi’s recent history of guerrilla warfare; and 3) Cosmetics and products used for body care, decoration and perfuming (e.g. hair care, teeth cleansing, henna use) and for aromatizing the air inside of tents and which are widely used in everyday life and social practices. Conclusions We discuss the changes that have occurred in the patterns of use and procurement of these products with exile and sedentarization in refugee camps, and conclude that refugees are not simply passive recipients of national and international aid, but rather struggle to maintain and recover their traditional ethnobiological practices in exile. Finally, we suggest further research into the ethnobiological practices and knowledge of displaced populations. Resumen Sanando las heridas de guerra y perfumando el exilio: el uso de productos vegetales, animales y minerales con fines de perfumería, cosmética y curativos de la piel entre los refugiados saharauis del Sáhara Occidental. Antecedentes Durante la última década ha habido un creciente interés en los estudios etnobiológicos de los conocimientos y prácticas de las personas que migran. Dentro de esta tendencia, los estudiosos han prestado relativamente menor atención a las personas desplazadas y a los refugiados: a la pérdida, el mantenimiento y la adaptación de sus conocimientos etnobiológicos, y su importancia para el bienestar de los refugiados. Este estudio se centra en los cosméticos y remedios para curar problemas de la piel tradicionalmente utilizados por los refugiados saharauis en los campamentos de desplazados al sudoeste de Argelia. Métodos Los métodos de investigación que se utilizaron son: una encuesta estructurada con 37 familias de refugiados, entrevistas semi-estructuradas con 77 refugiados, 24 entrevistas retrospectivas con refugiados e informantes conocedores, y una colección de muestra de las plantas y productos citados. Resultados Se registró el uso de 55 especies vegetales, nueve especies animales, y seis productos minerales utilizados en tres principales categorías de usos: 1) Recursos contra los problemas de salud característicos del entorno desértico donde una vez vivieron los saharauis como nómadas y donde ahora viven como refugiados (por ejemplo problemas en los ojos); 2) Remedios para heridas que reflejan la historia reciente de guerra de guerrilla de los nómadas saharauis; y 3) Cosméticos y productos utilizados para el cuidado del cuerpo, decoración y perfumes (por ejemplo, atención al cabello, limpieza de dientes, uso del henna) y como aromatizantes del aire al interior de las tiendas, que son ampliamente utilizados en la vida y las prácticas sociales cotidianas de los refugiados. Conclusiones En la discusión, se analizan los cambios que se han producido en los patrones de uso y en la adquisición de estos productos durante el exilio. Llegamos a la conclusión de que los refugiados no son recipientes pasivos de la ayuda nacional e internacional, sino más bien luchan para mantener y recuperar sus prácticas tradicionales etnobiológicas en el exilio. Finalmente, sugerimos nuevas direcciones para la investigación de las prácticas y los conocimientos etnobiológicos de las poblaciones desplazadas. PMID:23270531

  10. Cathepsin B Cysteine Proteinase is Essential for the Development and Pathogenesis of the Plant Parasitic Nematode Radopholus similis.

    PubMed

    Li, Yu; Wang, Ke; Xie, Hui; Wang, Dong-Wei; Xu, Chun-Ling; Huang, Xin; Wu, Wen-Jia; Li, Dan-Lei

    2015-01-01

    Radopholus similis is an important plant parasitic nematode which severely harms many crops. Cathepsin B is present in a wide variety of organisms, and plays an important role in many parasites. Understanding cathepsin B of R. similis would allow us to find new targets and approaches for its control. In this study, we found that Rs-cb-1 mRNA was expressed in esophageal glands, intestines and gonads of females, testes of males, juveniles and eggs in R. similis. Rs-cb-1 expression was the highest in females, followed by juveniles and eggs, and was the lowest in males. The maximal enzyme activity of Rs-CB-1 was detected at pH 6.0 and 40 °C. Silencing of Rs-cb-1 using in vitro RNAi (Soaking with dsRNA in vitro) not only significantly inhibited the development and hatching of R. similis, but also greatly reduced its pathogenicity. Using in planta RNAi, we confirmed that Rs-cb-1 expression in nematodes were significantly suppressed and the resistance to R. similis was significantly improved in T2 generation transgenic tobacco plants expressing Rs-cb-1 dsRNA. The genetic effects of in planta RNAi-induced gene silencing could be maintained in the absence of dsRNA for at least two generations before being lost, which was not the case for the effects induced by in vitro RNAi. Overall, our results first indicate that Rs-cb-1 plays key roles in the development, hatching and pathogenesis of R. similis, and that in planta RNAi is an effective tool in studying gene function and genetic engineering of plant resistance to migratory plant parasitic nematodes. PMID:26221074

  11. Evidence for widespread exonic small RNAs in the glaucophyte alga Cyanophora paradoxa.

    PubMed

    Gross, Jeferson; Wajid, Sana; Price, Dana C; Zelzion, Ehud; Li, Junyi; Chan, Cheong Xin; Bhattacharya, Debashish

    2013-01-01

    RNAi (RNA interference) relies on the production of small RNAs (sRNAs) from double-stranded RNA and comprises a major pathway in eukaryotes to restrict the propagation of selfish genetic elements. Amplification of the initial RNAi signal by generation of multiple secondary sRNAs from a targeted mRNA is catalyzed by RNA-dependent RNA polymerases (RdRPs). This phenomenon is known as transitivity and is particularly important in plants to limit the spread of viruses. Here we describe, using a genome-wide approach, the distribution of sRNAs in the glaucophyte alga Cyanophora paradoxa. C. paradoxa is a member of the supergroup Plantae (also known as Archaeplastida) that includes red algae, green algae, and plants. The ancient (>1 billion years ago) split of glaucophytes within Plantae suggests that C. paradoxa may be a useful model to learn about the early evolution of RNAi in the supergroup that ultimately gave rise to plants. Using next-generation sequencing and bioinformatic analyses we find that sRNAs in C. paradoxa are preferentially associated with mRNAs, including a large number of transcripts that encode proteins arising from different functional categories. This pattern of exonic sRNAs appears to be a general trend that affects a large fraction of mRNAs in the cell. In several cases we observe that sRNAs have a bias for a specific strand of the mRNA, including many instances of antisense predominance. The genome of C. paradoxa encodes four sequences that are homologous to RdRPs in Arabidopsis thaliana. We discuss the possibility that exonic sRNAs in the glaucophyte may be secondarily derived from mRNAs by the action of RdRPs. If this hypothesis is confirmed, then transitivity may have had an ancient origin in Plantae. PMID:23844054

  12. Cathepsin B Cysteine Proteinase is Essential for the Development and Pathogenesis of the Plant Parasitic Nematode Radopholus similis

    PubMed Central

    Li, Yu; Wang, Ke; Xie, Hui; Wang, Dong-Wei; Xu, Chun-Ling; Huang, Xin; Wu, Wen-Jia; Li, Dan-Lei

    2015-01-01

    Radopholus similis is an important plant parasitic nematode which severely harms many crops. Cathepsin B is present in a wide variety of organisms, and plays an important role in many parasites. Understanding cathepsin B of R. similis would allow us to find new targets and approaches for its control. In this study, we found that Rs-cb-1 mRNA was expressed in esophageal glands, intestines and gonads of females, testes of males, juveniles and eggs in R. similis. Rs-cb-1 expression was the highest in females, followed by juveniles and eggs, and was the lowest in males. The maximal enzyme activity of Rs-CB-1 was detected at pH 6.0 and 40 °C. Silencing of Rs-cb-1 using in vitro RNAi (Soaking with dsRNA in vitro) not only significantly inhibited the development and hatching of R. similis, but also greatly reduced its pathogenicity. Using in planta RNAi, we confirmed that Rs-cb-1 expression in nematodes were significantly suppressed and the resistance to R. similis was significantly improved in T2 generation transgenic tobacco plants expressing Rs-cb-1 dsRNA. The genetic effects of in planta RNAi-induced gene silencing could be maintained in the absence of dsRNA for at least two generations before being lost, which was not the case for the effects induced by in vitro RNAi. Overall, our results first indicate that Rs-cb-1 plays key roles in the development, hatching and pathogenesis of R. similis, and that in planta RNAi is an effective tool in studying gene function and genetic engineering of plant resistance to migratory plant parasitic nematodes. PMID:26221074

  13. Expression and glycoengineering of functionally active heteromultimeric IgM in plants

    PubMed Central

    Loos, Andreas; Gruber, Clemens; Altmann, Friedrich; Mehofer, Ulrich; Hensel, Frank; Grandits, Melanie; Oostenbrink, Chris; Stadlmayr, Gerhard; Furtmüller, Paul G.; Steinkellner, Herta

    2014-01-01

    IgM antibodies are an important player of the human’s innate defense mechanisms and increasingly have gained interest as therapeutics. Although the expression of IgM antibodies in mammalian cell culture is established, this approach remains costly and alternative methods have not been developed yet. Plants have a proven record for the production of therapeutically relevant recombinant proteins. However, whether they are able to express proteins like IgM antibodies, which range among the most complex human proteins, remains unknown so far. Here we report the in planta generation of the functionally active monoclonal antitumor IgM PAT-SM6 (SM6). SM6 efficiently accumulates in plant leaves and assembles correctly into heterooligomers (pentamers and hexamers). Detailed glycosylation analysis exhibited complex and oligomannosidic N-glycans in a site-specific manner on human-serum IgM and on plant- and human-cell-line–produced SM6. Moreover, extensive in planta glycoengineering allowed the generation of SM6 decorated with sialylated human-type oligosaccharides, comparable to plasma-derived IgM. A glycosylated model of pentameric IgM exhibits different accessibility of the glycosylation sites, explaining site-specific glycosylation. Biochemical and biophysical properties and importantly biological activities of plant-derived SM6 glycoforms are comparable to the human-cell–derived counterparts. The in planta generation of one of the most complex human proteins opens new pathways toward the production of difficult-to-express proteins for pharmaceutical applications. Moreover, the generation of IgMs with a controlled glycosylation pattern allows the study of the so far unknown contribution of sugar moieties to the function of IgMs. PMID:24706782

  14. Revised Phylogeny and Novel Horizontally Acquired Virulence Determinants of the Model Soft Rot Phytopathogen Pectobacterium wasabiae SCC3193

    PubMed Central

    Koskinen, Patrik; Nokso-Koivisto, Jussi; Pasanen, Miia; Broberg, Martin; Plyusnin, Ilja; Trnen, Petri; Holm, Liisa; Pirhonen, Minna; Palva, E. Tapio

    2012-01-01

    Soft rot disease is economically one of the most devastating bacterial diseases affecting plants worldwide. In this study, we present novel insights into the phylogeny and virulence of the soft rot model Pectobacterium sp. SCC3193, which was isolated from a diseased potato stem in Finland in the early 1980s. Genomic approaches, including proteome and genome comparisons of all sequenced soft rot bacteria, revealed that SCC3193, previously included in the species Pectobacterium carotovorum, can now be more accurately classified as Pectobacterium wasabiae. Together with the recently revised phylogeny of a few P. carotovorum strains and an increasing number of studies on P. wasabiae, our work indicates that P. wasabiae has been unnoticed but present in potato fields worldwide. A combination of genomic approaches and in planta experiments identified features that separate SCC3193 and other P. wasabiae strains from the rest of soft rot bacteria, such as the absence of a type III secretion system that contributes to virulence of other soft rot species. Experimentally established virulence determinants include the putative transcriptional regulator SirB, two partially redundant type VI secretion systems and two horizontally acquired clusters (Vic1 and Vic2), which contain predicted virulence genes. Genome comparison also revealed other interesting traits that may be related to life in planta or other specific environmental conditions. These traits include a predicted benzoic acid/salicylic acid carboxyl methyltransferase of eukaryotic origin. The novelties found in this work indicate that soft rot bacteria have a reservoir of unknown traits that may be utilized in the poorly understood latent stage in planta. The genomic approaches and the comparison of the model strain SCC3193 to other sequenced Pectobacterium strains, including the type strain of P. wasabiae, provides a solid basis for further investigation of the virulence, distribution and phylogeny of soft rot bacteria and, potentially, other bacteria as well. PMID:23133391

  15. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life

    NASA Technical Reports Server (NTRS)

    Margulis, L.

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae.

  16. Dual Effect of the Cubic Ag3PO4 Crystal on Pseudomonas syringae Growth and Plant Immunity

    PubMed Central

    Kim, Mi Kyung; Yeo, Byul-Ee; Park, Heonyong; Huh, Young-Duk; Kwon, Chian; Yun, Hye Sup

    2016-01-01

    We previously found that the antibacterial activity of silver phosphate crystals on Escherichia coli depends on their structure. We here show that the cubic form of silver phosphate crystal (SPC) can also be applied to inhibit the growth of a plant-pathogenic Pseudomonas syringae bacterium. SPC pretreatment resulted in reduced in planta multiplication of P. syringae. Induced expression of a plant defense marker gene PR1 by SPC alone is suggestive of its additional plant immunity-stimulating activity. Since SPC can simultaneously inhibit P. syringae growth and induce plant defense responses, it might be used as a more effective plant disease-controlling agent. PMID:27147937

  17. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life.

    PubMed

    Margulis, L

    1996-02-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae. PMID:8577716

  18. Nonlinear ribosome migration on cauliflower mosaic virus 35S RNA in transgenic tobacco plants.

    PubMed

    Schärer-Hernández, N; Hohn, T

    1998-03-15

    Cauliflower mosaic virus (CaMV) uses a specialised translation mechanism to bypass the long leader sequence of the 35S RNA. The effect of the CaMV 35S RNA leader sequence on the expression of a downstream beta-glucuronidase (GUS) reporter gene was studied in transgenic tobacco plants. Enzymatic GUS assays of these transgenic plants show that a shunt mechanism of translation indeed occurs in planta with an average efficiency of 5% compared with the leaderless construct. Histological GUS analyses indicate that the shunt mechanism occurs throughout the whole plant and at all developmental stages. PMID:9514980

  19. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life.

    PubMed Central

    Margulis, L

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae. Images Fig. 1 PMID:8577716

  20. PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

    PubMed

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frédéric; Nicolè, Florence; Raymond, Olivier; Huguet, Stéphanie; Baltenweck, Raymonde; Meyer, Sophie; Claudel, Patricia; Jeauffre, Julien; Rohmer, Michel; Foucher, Fabrice; Hugueney, Philippe; Bendahmane, Mohammed; Baudino, Sylvie

    2015-07-01

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta. PMID:26138978

  1. A High-Throughput Forward Genetic Screen Identifies Genes Required for Virulence of Pseudomonas syringae pv. maculicola ES4326 on Arabidopsis

    PubMed Central

    Schreiber, Karl J.; Ye, David; Fich, Eric; Jian, Allen; Lo, Timothy; Desveaux, Darrell

    2012-01-01

    Successful pathogenesis requires a number of coordinated processes whose genetic bases remain to be fully characterized. We utilized a high-throughput, liquid media-based assay to screen transposon disruptants of the phytopathogen Pseudomonas syringae pv. maculicola ES4326 to identify genes required for virulence on Arabidopsis. Many genes identified through this screen were involved in processes such as type III secretion, periplasmic glucan biosynthesis, flagellar motility, and amino acid biosynthesis. A small set of genes did not fall into any of these functional groups, and their disruption resulted in context-specific effects on in planta bacterial growth. PMID:22870224

  2. Sobrevivendo a un tsunami: lecciones de Chile, Hawai y Japon

    USGS Publications Warehouse

    Compilado por Atwater, Brian F.; Cisternas V., Marco; Bourgeois, Joanne; Dudley, Walter C.; Hendley, James W., II; Stauffer, Peter H.

    1999-01-01

    Este folleto contiene historias veridicas que ilustran como sobrevivir, y como no sobrevivir, a un tsunami. Esta publicacion esta dirigida a las personas que viven, trabajan o, simplemente, se divierten a lo largo de las costas que pueden ser afectadas por un tsunami. Tales costas rodean la mayor parte del Oceano Pacifico pero tambien incluyen algunas areas costeras de los Oceanos Atlantico e Indico. Aunque mucha gente llama a los tsunamis 'olas de marea', estos no estan relacionados a las mareas, sino son una serie de olas, o 'tren de olas', generalmente causadas por cambios en el nivel del fondo marino durante los terremotos. Los tsunamis tambien pueden ser generados por la erupcion de volcanes costeros, islas volconicas, deslizamientos submarinos e impactos de grandes meteoritos en el mar. Como sucedio en Sumatra en el 2004, los tsunamis pueden alcanzar alturas de 15 metros, no tan solo en la costa sino tambien kilometros tierra adentro. Los relatos presentados en este folleto fueron seleccionados de entrevistas realizadas a personas que sobrevivieron al tsunami del Oceano Pacifico de 1960. Muchas de estas personas, incluyendo a la enfermera de la foto, se enfrento a las olas generadas a poca distancia, en la costa chilena. En cambio, otros debieron hacer frente al tsunami muchas horas despues, en Hawai y Japon. La mayoria de las entrevistas fueron realizadas a fines de los anos ochenta y en los noventa. Las historias ofrecen una mezcla de lecciones de supervivencia a un tsunami. En algunos casos se presentan las acciones que confiablemente salvaron vidas: poner atencion a los avisos de la naturaleza, abandonar los bienes, dirigirse rapidamente a un sector alto y permanecer alli hasta que el tsunami realmente haya terminado. Otras historias describen como se encontro refugio al subir a construcciones y arboles o flotar sobre desechos, tacticas que tuvieron diferentes resultados y que pueden ser recomendadas solo como actos desesperados de personas atrapadas en sectores bajos.

  3. Agregación de para-H2 en chorros supersónicos: del dímero al sólido

    NASA Astrophysics Data System (ADS)

    María Fernández, José

    En este trabajo se mostrarán los estudios de expansiones supersónicas de para-H2 desde toberas criogénicas, realizados en el laboratorio de Fluidodinámica Molecular del IEM. Hemos registrado los espectros Raman de dichas expansiones en el intervalo de frecuencias de 4145 a 4162 cm-1, próximo a la línea Q(0) del monómero no rotante H2, a 4161.18 cm-1. En el espectro Raman, además de la línea Q(0) del monómero, se observan unos picos débiles, que, por su comportamiento con la temperatura de la tobera y la distancia a la misma, asignamos a la transición homóloga en agregados de p-H2. Dependiendo de las condiciones, se observan agregados pequeños (de 2 a 13 moléculas de p-H2), agregados medios y masivos, y se llega incluso al líquido y al sólido. Las asignaciones se apoyan en un modelo sencillo, basado en la perturbación, debida al potencial intermolecular, de los estados vibracionales v=0 y v=1 en los agregados de p-H2. Se mostrarán detalles de la instalación experimental, ejemplos de los espectros obtenidos en diversas condiciones, y detalles de la interpretación cuantitativa.

  4. Mecanismos cinéticos y distribuciones energéticas de iones (H3+, N2H+, CH3+...) en plasmas fríos de H2/N2/CH4

    NASA Astrophysics Data System (ADS)

    Tanarro, I.; Herrero, V. J.; Islyaikin, A.; Tabarés, F. L.; Tafalla, D.

    En este trabajo se presenta el estudio espectrométrico de los plasmas levemente ionizados generados en una descarga continua a baja presión de H2 con trazas de N2 y CH4, orientado principalmente a identificar la naturaleza y distribución energética de los iones que en ella se producen, y a asignar algunos de los mecanismos cinéticos elementales de formación y destrucción de tales especies. Alguno de los iones mayoritarios de estos plasmas, como el H3+, presenta gran interés desde el punto de vista de la Astrofísica por su prevista intervención en la química de las ionosferas planetarias y del medio interestelar, al actuar como sustancia intermedia en la formación de gran variedad de especies moleculares; si bien, dada su pequeña concentración, su observación real en el espacio se demoró hasta la pasada década de los años 90, cuando fue detectado por primera vez en la atmósfera de Júpiter y en otros objetos estelares. Del mismo modo que los trabajos espectroscópicos de laboratorio resultan indispensables para la posterior identificación de las especies observadas en el espacio, es de esperar que la asignación de los procesos cinéticos más importantes que tienen lugar en los plasmas generados en reactores de descarga, como los aquí presentados, permitan extrapolar los resultados así obtenidos al esclarecimiento de los mecanismos fisico-químicos participantes en otros medios observables únicamente a larga distancia.

  5. Root Uptake of Pharmaceuticals and Personal Care Product Ingredients.

    PubMed

    Miller, Elizabeth L; Nason, Sara L; Karthikeyan, K G; Pedersen, Joel A

    2016-01-19

    Crops irrigated with reclaimed wastewater or grown in biosolids-amended soils may take up pharmaceuticals and personal care product ingredients (PPCPs) through their roots. The uptake pathways followed by PPCPs and the propensity for these compounds to bioaccumulate in food crops are still not well understood. In this critical review, we discuss processes expected to influence root uptake of PPCPs, evaluate current literature on uptake of PPCPs, assess models for predicting plant uptake of these compounds, and provide recommendations for future research, highlighting processes warranting study that hold promise for improving mechanistic understanding of plant uptake of PPCPs. We find that many processes that are expected to influence PPCP uptake and accumulation have received little study, particularly rhizosphere interactions, in planta transformations, and physicochemical properties beyond lipophilicity (as measured by Kow). Data gaps and discrepancies in methodology and reporting have so far hindered development of models that accurately predict plant uptake of PPCPs. Topics warranting investigation in future research include the influence of rhizosphere processes on uptake, determining mechanisms of uptake and accumulation, in planta transformations, the effects of PPCPs on plants, and the development of predictive models. PMID:26619126

  6. Mining secreted proteins that function in pepper fruit development and ripening using a yeast secretion trap (YST)

    SciTech Connect

    Lee, Je Min; Lee, Sang-Jik; Rose, Jocelyn K.C.; Yeam, Inhwa; Kim, Byung-Dong

    2014-04-18

    Highlights: • Yeast secretion trap (YST) is a valuable tool for mining secretome. • A total of 80 secreted proteins are newly identified via YST in pepper fruits. • The secreted proteins are differentially regulated during pepper development and ripening. • Transient GFP-fusion assay and in planta secretion trap can effectively validate the secretion of proteins. - Abstract: Plant cells secrete diverse sets of constitutively- and conditionally-expressed proteins under various environmental and developmental states. Secreted protein populations, or secretomes have multiple functions, including defense responses, signaling, metabolic processes, and developmental regulation. To identify genes encoding secreted proteins that function in fruit development and ripening, a yeast secretion trap (YST) screen was employed using pepper (Capsicum annuum) fruit cDNAs. The YST screen revealed 80 pepper fruit-related genes (CaPFRs) encoding secreted proteins including cell wall proteins, several of which have not been previously described. Transient GFP-fusion assay and an in planta secretion trap were used to validate the secretion of proteins encoded by selected YST clones. In addition, RNA gel blot analyses provided further insights into their expression and regulation during fruit development and ripening. Integrating our data, we conclude that the YST provides a valuable functional genomics tool for the identification of substantial numbers of novel secreted plant proteins that are associated with biological processes, including fruit development and ripening.

  7. Holophytochrome-Interacting Proteins in Physcomitrella: Putative Actors in Phytochrome Cytoplasmic Signaling

    PubMed Central

    Ermert, Anna Lena; Mailliet, Katharina; Hughes, Jon

    2016-01-01

    Phytochromes are the principle photoreceptors in light-regulated plant development, primarily acting via translocation of the light-activated photoreceptor into the nucleus and subsequent gene regulation. However, several independent lines of evidence indicate unambiguously that an additional cytoplasmic signaling mechanism must exist. Directional responses in filament tip cells of the moss Physcomitrella patens are steered by phy4 which has been shown to interact physically with the blue light receptor phototropin at the plasma membrane. This complex might perceive and transduce vectorial information leading to cytoskeleton reorganization and finally a directional growth response. We developed yeast two-hybrid procedures using photochemically functional, full-length phy4 as bait in Physcomitrella cDNA library screens and growth assays under different light conditions, revealing Pfr-dependent interactions possibly associated with phytochrome cytoplasmic signaling. Candidate proteins were then expressed in planta with fluorescent protein tags to determine their intracellular localization in darkness and red light. Of 14 candidates, 12 were confirmed to interact with phy4 in planta using bimolecular fluorescence complementation. We also used database information to study their expression patterns relative to those of phy4. We discuss the likely functional characteristics of these holophytochrome-interacting proteins (HIP’s) and their possible roles in signaling.

  8. A Phytophthora infestans RXLR effector targets plant PP1c isoforms that promote late blight disease

    PubMed Central

    Boevink, Petra C.; Wang, Xiaodan; McLellan, Hazel; He, Qin; Naqvi, Shaista; Armstrong, Miles R.; Zhang, Wei; Hein, Ingo; Gilroy, Eleanor M.; Tian, Zhendong; Birch, Paul R. J.

    2016-01-01

    Plant pathogens deliver effectors to alter host processes. Knowledge of how effectors target and manipulate host proteins is critical to understand crop disease. Here, we show that in planta expression of the RXLR effector Pi04314 enhances leaf colonization by Phytophthora infestans via activity in the host nucleus and attenuates induction of jasmonic and salicylic acid-responsive genes. Pi04314 interacts with three host protein phosphatase 1 catalytic (PP1c) isoforms, causing their re-localization from the nucleolus to the nucleoplasm. Re-localization of PP1c-1 also occurs during infection and is dependent on an R/KVxF motif in the effector. Silencing the PP1c isoforms or overexpression of a phosphatase-dead PP1c-1 mutant attenuates infection, demonstrating that host PP1c activity is required for disease. Moreover, expression of PP1c–1mut abolishes enhanced leaf colonization mediated by in planta Pi04314 expression. We argue that PP1c isoforms are susceptibility factors forming holoenzymes with Pi04314 to promote late blight disease. PMID:26822079

  9. Polar Localizing Class V Myosin Chitin Synthases Are Essential during Early Plant Infection in the Plant Pathogenic Fungus Ustilago maydisW⃞

    PubMed Central

    Weber, Isabella; Aßmann, Daniela; Thines, Eckhard; Steinberg, Gero

    2006-01-01

    Fungal chitin synthases (CHSs) form fibers of the cell wall and are crucial for substrate invasion and pathogenicity. Filamentous fungi contain up to 10 CHSs, which might reflect redundant functions or the complex biology of these fungi. Here, we investigate the complete repertoire of eight CHSs in the dimorphic plant pathogen Ustilago maydis. We demonstrate that all CHSs are expressed in yeast cells and hyphae. Green fluorescent protein (GFP) fusions to all CHSs localize to septa, whereas Chs5-GFP, Chs6-GFP, Chs7-yellow fluorescent protein (YFP), and Myosin chitin synthase1 (Mcs1)-YFP were found at growth regions of yeast-like cells and hyphae, indicating that they participate in tip growth. However, only the class IV CHS genes chs7 and chs5 are crucial for shaping yeast cells and hyphae ex planta. Although most CHS mutants were attenuated in plant pathogenicity, Δchs6, Δchs7, and Δmcs1 mutants were drastically reduced in virulence. Δmcs1 showed no morphological defects in hyphae, but Mcs1 became essential during invasion of the plant epidermis. Δmcs1 hyphae entered the plant but immediately lost growth polarity and formed large aggregates of spherical cells. Our data show that the polar class IV CHSs are essential for morphogenesis ex planta, whereas the class V myosin-CHS is essential during plant infection. PMID:16314447

  10. Characterization of VuMATE1 Expression in Response to Iron Nutrition and Aluminum Stress Reveals Adaptation of Rice Bean (Vigna umbellata) to Acid Soils through Cis Regulation.

    PubMed

    Liu, Meiya; Xu, Jiameng; Lou, Heqiang; Fan, Wei; Yang, Jianli; Zheng, Shaojian

    2016-01-01

    Rice bean (Vigna umbellata) VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acid soils where Al stress imposed but Fe deficiency pressure released. PMID:27148333

  11. Loss of the nodule-specific cysteine rich peptide, NCR169, abolishes symbiotic nitrogen fixation in the Medicago truncatula dnf7 mutant.

    PubMed

    Horvth, Beatrix; Domonkos, gota; Kereszt, Attila; Sz?cs, Attila; brahm, Edit; Ayaydin, Ferhan; Bka, Kroly; Chen, Yuhui; Chen, Rujin; Murray, Jeremy D; Udvardi, Michael K; Kondorosi, va; Kal, Pter

    2015-12-01

    Host compatible rhizobia induce the formation of legume root nodules, symbiotic organs within which intracellular bacteria are present in plant-derived membrane compartments termed symbiosomes. In Medicago truncatula nodules, the Sinorhizobium microsymbionts undergo an irreversible differentiation process leading to the development of elongated polyploid noncultivable nitrogen fixing bacteroids that convert atmospheric dinitrogen into ammonia. This terminal differentiation is directed by the host plant and involves hundreds of nodule specific cysteine-rich peptides (NCRs). Except for certain in vitro activities of cationic peptides, the functional roles of individual NCR peptides in planta are not known. In this study, we demonstrate that the inability of M. truncatula dnf7 mutants to fix nitrogen is due to inactivation of a single NCR peptide, NCR169. In the absence of NCR169, bacterial differentiation was impaired and was associated with early senescence of the symbiotic cells. Introduction of the NCR169 gene into the dnf7-2/NCR169 deletion mutant restored symbiotic nitrogen fixation. Replacement of any of the cysteine residues in the NCR169 peptide with serine rendered it incapable of complementation, demonstrating an absolute requirement for all cysteines in planta. NCR169 was induced in the cell layers in which bacteroid elongation was most pronounced, and high expression persisted throughout the nitrogen-fixing nodule zone. Our results provide evidence for an essential role of NCR169 in the differentiation and persistence of nitrogen fixing bacteroids in M. truncatula. PMID:26401023

  12. Austrian pine phenolics are likely contributors to systemic induced resistance against Diplodia pinea.

    PubMed

    Sherwood, Patrick; Bonello, Pierluigi

    2013-08-01

    The molecular basis of the systemic induced resistance (SIR) phenotype known to occur in Austrian pine (Pinus nigra J.F. Arnold) in response to the tip blight and canker pathogen Diplodia pinea (Desm.) remains unclear. Specialized metabolites such as phenolics are considered to be an important component of plant defense, including SIR, but the antimicrobial activity of many of these putative defensive chemicals remains untested at realistic concentrations and in conjunction with each other. Here, we examined the anti-Diplodia activity of several previously identified Austrian pine phenolics associated with SIR by comparing the diameters of fungal colonies grown on media amended with ferulic acid, coumaric acid, taxifolin, pinosylvin, pinosylvin monomethyl ether and lignin. All of the compounds were tested both individually and as clusters (combinations) previously determined to occur in planta in a co-regulated fashion. Both the individual compounds and clusters were tested at constitutive concentrations and pathogen-induced concentrations linked to an SIR phenotype. Lignin possessed the strongest antifungal activity individually, and clusters at the SIR concentrations had the greatest antifungal effects, achieving fungistasis. This study exemplifies the value of evaluating potential biomarkers of resistance at in planta concentrations that are associated with the systemically resistant phenotype, and provides strong evidence that co-regulation of chemical defenses potentiates such a phenotype. PMID:23999139

  13. Molecular characterization and functional analyses of ZtWor1, a transcriptional regulator of the fungal wheat pathogen Zymoseptoria tritici.

    PubMed

    Mirzadi Gohari, Amir; Mehrabi, Rahim; Robert, Olivier; Ince, Ikbal Agah; Boeren, Sjef; Schuster, Martin; Steinberg, Gero; de Wit, Pierre J G M; Kema, Gert H J

    2014-05-01

    Zymoseptoria tritici causes the major fungal wheat disease septoria tritici blotch, and is increasingly being used as a model for transmission and population genetics, as well as host-pathogen interactions. Here, we study the biological function of ZtWor1, the orthologue of Wor1 in the fungal human pathogen Candida albicans, as a representative of a superfamily of regulatory proteins involved in dimorphic switching. In Z. tritici, this gene is pivotal for pathogenesis, as ZtWor1 mutants were nonpathogenic and complementation restored the wild-type phenotypes. In planta expression analyses showed that ZtWor1 is up-regulated during the initiation of colonization and fructification, and regulates candidate effector genes, including one that was discovered after comparative proteome analysis of the Z. tritici wild-type strain and the ZtWor1 mutant, which was particularly expressed in planta. Cell fusion and anastomosis occur frequently in ZtWor1 mutants, reminiscent of mutants of MgGpb1, the β-subunit of the heterotrimeric G protein. Comparative expression of ZtWor1 in knock-out strains of MgGpb1 and MgTpk2, the catalytic subunit of protein kinase A, suggests that ZtWor1 is downstream of the cyclic adenosine monophosphate (cAMP) pathway that is crucial for pathogenesis in many fungal plant pathogens. PMID:24341593

  14. The future of starch bioengineering: GM microorganisms or GM plants?

    PubMed

    Hebelstrup, Kim H; Sagnelli, Domenico; Blennow, Andreas

    2015-01-01

    Plant starches regularly require extensive modification to permit subsequent applications. Such processing is usually done by the use of chemical and/or physical treatments. The use of recombinant enzymes produced by large-scale fermentation of GM microorganisms is increasingly used in starch processing and modification, sometimes as an alternative to chemical or physical treatments. However, as a means to impart the modifications as early as possible in the starch production chain, similar recombinant enzymes may also be expressed in planta in the developing starch storage organ such as in roots, tubers and cereal grains to provide a GM crop as an alternative to the use of enzymes from GM microorganisms. We here discuss these techniques in relation to important structural features and modifications of starches such as: starch phosphorylation, starch hydrolysis, chain transfer/branching and novel concepts of hybrid starch-based polysaccharides. In planta starch bioengineering is generally challenged by yield penalties and inefficient production of the desired product. However, in some situations, GM crops for starch bioengineering without deleterious effects have been achieved. PMID:25954284

  15. Acetylation of woody lignocellulose: significance and regulation

    PubMed Central

    Pawar, Prashant Mohan-Anupama; Koutaniemi, Sanna; Tenkanen, Maija; Mellerowicz, Ewa J.

    2013-01-01

    Non-cellulosic cell wall polysaccharides constitute approximately one quarter of usable biomass for human exploitation. In contrast to cellulose, these components are usually substituted by O-acetyl groups, which affect their properties and interactions with other polymers, thus affecting their solubility and extractability. However, details of these interactions are still largely obscure. Moreover, polysaccharide hydrolysis to constituent monosaccharides is hampered by the presence of O-acetyl groups, necessitating either enzymatic (esterase) or chemical de-acetylation, increasing the costs and chemical consumption. Reduction of polysaccharide acetyl content in planta is a way to modify lignocellulose toward improved saccharification. In this review we: (1) summarize literature on lignocellulose acetylation in different tree species, (2) present data and current hypotheses concerning the role of O-acetylation in determining woody lignocellulose properties, (3) describe plant proteins involved in lignocellulose O-acetylation, (4) give examples of microbial enzymes capable to de-acetylate lignocellulose, and (5) discuss prospects for exploiting these enzymes in planta to modify xylan acetylation. PMID:23734153

  16. Precursor feeding studies and molecular characterization of geraniol synthase establish the limiting role of geraniol in monoterpene indole alkaloid biosynthesis in Catharanthus roseus leaves.

    PubMed

    Kumar, Krishna; Kumar, Sarma Rajeev; Dwivedi, Varun; Rai, Avanish; Shukla, Ashutosh K; Shanker, Karuna; Nagegowda, Dinesh A

    2015-10-01

    The monoterpene indole alkaloids (MIAs) are generally derived from strictosidine, which is formed by condensation of the terpene moiety secologanin and the indole moiety tryptamine. There are conflicting reports on the limitation of either terpene or indole moiety in the production of MIAs in Catharanthus roseus cell cultures. Formation of geraniol by geraniol synthase (GES) is the first step in secologanin biosynthesis. In this study, feeding of C. roseus leaves with geraniol, but not tryptophan (precursor for tryptamine), increased the accumulation of the MIAs catharanthine and vindoline, indicating the limitation of geraniol in MIA biosynthesis. This was further validated by molecular and in planta characterization of C. roseus GES (CrGES). CrGES transcripts exhibited leaf and shoot specific expression and were induced by methyl jasmonate. Virus-induced gene silencing (VIGS) of CrGES significantly reduced the MIA content, which was restored to near-WT levels upon geraniol feeding. Moreover, over-expression of CrGES in C. roseus leaves increased MIA content. Further, CrGES exhibited correlation with MIA levels in leaves of different C. roseus cultivars and has significantly lower expression relative to other pathway genes. These results demonstrated that the transcriptional regulation of CrGES and thus, the in planta geraniol availability plays crucial role in MIA biosynthesis. PMID:26398791

  17. Analysis of the interaction of Clavibacter michiganensis subsp. michiganensis with its host plant tomato by genome-wide expression profiling.

    PubMed

    Flügel, Monika; Becker, Anke; Gartemann, Karl-Heinz; Eichenlaub, Rudolf

    2012-07-31

    Genome-wide expression profiles of the phytopathogenic actinomycete Clavibacter michiganensis subsp. michiganensis (Cmm) strain NCPPB382 were analyzed using a 70mer oligonucleotide microarray. Cmm causes bacterial wilt and canker of tomato, a systemic disease leading to substantial economic losses worldwide. Global gene expression was monitored in vitro after long- and short-term incubation with tomato homogenate to simulate conditions in planta and in vivo ten days after inoculation of tomatoes. Surprisingly, both in the presence of tomato homogenate and in planta known virulence genes (celA, chpC, ppaA/C) were down-regulated indicating that the encoded extracellular enzymes are dispensable in late infection stages where plant tissue has already been heavily destroyed. In contrast, some genes of the tomA-region which are involved in sugar metabolism showed an enhanced RNA-level after permanent growth in supplemented medium. Therefore, these genes may be important for utilization of plant derived nutrients. In the plant Cmm exhibited an expression profile completely different from that in vitro. Especially, the strong expression of genes of the wco-cluster (extracellular polysaccharide II), 10 genes encoding surface or pilus assembly proteins, and CMM_2382, coding for a putative perforin suggest a possible role of these genes in the plant-pathogenic interaction. PMID:22326627

  18. Production of DAPG and HCN by Pseudomonas sp. LBUM300 contributes to the biological control of bacterial canker of tomato.

    PubMed

    Lanteigne, Carine; Gadkar, Vijay J; Wallon, Thrse; Novinscak, Amy; Filion, Martin

    2012-10-01

    Bacterial canker caused by Clavibacter michiganensis subsp. michiganensis is known to cause significant economic losses to tomato production worldwide. Biological control has been proposed as an alternative to current chemical containment methods, which are often inefficient and may leave adverse effects on the environment. However, only little headway has so far been made in developing biocontrol strategies against C. michiganensis subsp. michiganensis. To address this knowledge gap, we investigated the antagonistic capacity of PCA, produced by Pseudomonas sp. LBUM223, and DAPG and HCN, both produced by Pseudomonas sp. LBUM300, on C. michiganensis subsp. michiganensis under in vitro and in planta conditions. Nonsynthesizing isogenic mutants of the producer strains were also developed to further dissect the role of each individual metabolite on C. michiganensis subsp. michiganensis biological control. Novel specific quantitative polymerase chain reaction TaqMan assays allowed quantification of C. michiganensis subsp. michiganensis in tomato plants and rhizospheric soil. Pseudomonas spp. LBUM223 and LBUM300 significantly repressed C. michiganensis subsp. michiganensis growth in vitro, while their respective nonproducing mutants showed less or no significant antagonistic activity. In planta, only Pseudomonas sp. LBUM300 was capable of significantly reducing disease development and C. michiganensis subsp. michiganensis rhizospheric population, suggesting that the production of both DAPG and HCN was involved. In summary, simultaneous DAPG/HCN production by Pseudomonas sp. LBUM300 shows great potential for controlling bacterial canker of tomato. PMID:22713078

  19. Kelps feature systemic defense responses: insights into the evolution of innate immunity in multicellular eukaryotes.

    PubMed

    Thomas, François; Cosse, Audrey; Le Panse, Sophie; Kloareg, Bernard; Potin, Philippe; Leblanc, Catherine

    2014-11-01

    Brown algae are one of the few eukaryotic lineages that have evolved complex multicellularity, together with Opisthokonts (animals, fungi) and Plantae (land plants, green and red algae). In these three lineages, biotic stresses induce similar local defense reactions. Animals and land plants also feature a systemic immune response, protecting the whole organism after an attack on one of its parts. However, the occurrence of systemic defenses has never been investigated in brown algae. We elicited selected parts of the kelp Laminaria digitata and monitored distant, nonchallenged areas of the same individual for subsequent defense reactions. A systemic reaction was detected following elicitation on a distant area, including an oxidative response, an increase in haloperoxidase activities and a stronger resistance against herbivory. Based on experiments with pharmacological inhibitors, the liberation of free fatty acids is proposed to play a key role in systemic signaling, reminiscent of what is known in land plants. This study is the first report, outside the phyla of Opisthokonts and Plantae, of an intraorganism communication leading to defense reactions. These findings indicate that systemic immunity emerged independently at least three times, as a consequence of convergent evolution in multicellular eukaryotic lineages. PMID:25041157

  20. Phenylcoumaran benzylic ether reductase prevents accumulation of compounds formed under oxidative conditions in poplar xylem.

    PubMed

    Niculaes, Claudiu; Morreel, Kris; Kim, Hoon; Lu, Fachuang; McKee, Lauren S; Ivens, Bart; Haustraete, Jurgen; Vanholme, Bartel; Rycke, Riet De; Hertzberg, Magnus; Fromm, Jorg; Bulone, Vincent; Polle, Andrea; Ralph, John; Boerjan, Wout

    2014-09-01

    Phenylcoumaran benzylic ether reductase (PCBER) is one of the most abundant proteins in poplar (Populus spp) xylem, but its biological role has remained obscure. In this work, metabolite profiling of transgenic poplar trees downregulated in PCBER revealed both the in vivo substrate and product of PCBER. Based on mass spectrometry and NMR data, the substrate was identified as a hexosylated 8-5-coupling product between sinapyl alcohol and guaiacylglycerol, and the product was identified as its benzyl-reduced form. This activity was confirmed in vitro using a purified recombinant PCBER expressed in Escherichia coli. Assays performed on 20 synthetic substrate analogs revealed the enzyme specificity. In addition, the xylem of PCBER-downregulated trees accumulated over 2000-fold higher levels of cysteine adducts of monolignol dimers. These compounds could be generated in vitro by simple oxidative coupling assays involving monolignols and cysteine. Altogether, our data suggest that the function of PCBER is to reduce phenylpropanoid dimers in planta to form antioxidants that protect the plant against oxidative damage. In addition to describing the catalytic activity of one of the most abundant enzymes in wood, we provide experimental evidence for the antioxidant role of a phenylpropanoid coupling product in planta. PMID:25238751

  1. Combining metabolomics and gene expression analysis reveals that propionyl- and butyryl-carnitines are involved in late stages of arbuscular mycorrhizal symbiosis.

    PubMed

    Laparre, Jérôme; Malbreil, Mathilde; Letisse, Fabien; Portais, Jean Charles; Roux, Christophe; Bécard, Guillaume; Puech-Pagès, Virginie

    2014-03-01

    The arbuscular mycorrhizal (AM) symbiosis is a widespread mutualistic association between soil fungi (Glomeromycota) and the roots of most plant species. AM fungi are obligate biotrophs whose development is partially under the control of their plant host. We explored the possibility to combine metabolomic and transcriptomic approaches to find putative mycorrhiza-associated metabolites regulating AM fungal development. Methanol extracts of Medicago truncatula roots colonized or not with the AM fungus Rhizophagus irregularis were analyzed and compared by ultra-high-performance liquid chromatography (UHPLC), high-resolution mass spectrometry (Q-TOF), and multivariate statistical discrimination. We detected 71 mycorrhiza-associated analytes exclusively present or at least 10-fold more abundant in mycorrhizal roots. To identify among these analytes those that could regulate AM fungal development, we fractionated by preparative and semi-preparative HPLC the mycorrhizal and non-mycorrhizal root extracts and established how the 71 analytes were distributed among the fractions. Then we tested the activity of the fractions on germinating spores of R. irregularis by quantifying the expression of 96 genes known for their diverse in planta expression patterns. These investigations reveal that propionyl- and butyryl-carnitines accumulated in mycorrhizal roots. The results suggest that these two molecules regulate fungal gene expression in planta and represent interesting candidates for further biological characterization. PMID:24121293

  2. Global and grain-specific accumulation of glycoside hydrolase family 10 xylanases in transgenic maize (Zea mays).

    PubMed

    Gray, Benjamin N; Bougri, Oleg; Carlson, Alvar R; Meissner, Judy; Pan, Shihao; Parker, Matthew H; Zhang, Dongcheng; Samoylov, Vladimir; Ekborg, Nathan A; Michael Raab, R

    2011-12-01

    In planta expression of cell wall degrading enzymes is a promising approach for developing optimized biomass feedstocks that enable low-cost cellulosic biofuels production. Transgenic plants could serve as either an enzyme source for the hydrolysis of pretreated biomass or as the primary biomass feedstock in an autohydrolysis process. In this study, two xylanase genes, Bacillus sp. NG-27 bsx and Clostridium stercorarium xynB, were expressed in maize (Zea mays) under the control of two different promoters. Severe phenotypic effects were associated with xylanase accumulation in maize, including stunted plants and sterile grains. Global expression of these xylanases from the rice ubiquitin 3 promoter (rubi3) resulted in enzyme accumulation of approximately 0.01 mg enzyme per gram dry weight, or approximately 0.1% of total soluble protein (TSP). Grain-specific expression of these enzymes from the rice glutelin 4 promoter (GluB-4) resulted in higher-level accumulation of active enzyme, with BSX and XynB accumulating up to 4.0% TSP and 16.4% TSP, respectively, in shriveled grains from selected T0 plants. These results demonstrate the potential utility of the GluB-4 promoter for biotechnological applications. The phenotypic effects of xylanase expression in maize presented here demonstrate the difficulties of hemicellulase expression in an important crop for cellulosic biofuels production. Potential alternate approaches to achieve xylanase accumulation in planta without the accompanying negative phenotypes are discussed. PMID:21689368

  3. Expansive Phenotypic Landscape of Botrytis cinerea Shows Differential Contribution of Genetic Diversity and Plasticity.

    PubMed

    Corwin, Jason A; Subedy, Anushriya; Eshbaugh, Robert; Kliebenstein, Daniel J

    2016-04-01

    The modern evolutionary synthesis suggests that both environmental variation and genetic diversity are critical determinants of pathogen success. However, the relative contribution of these two sources of variation is not routinely measured. To estimate the relative contribution of plasticity and genetic diversity for virulence-associated phenotypes in a generalist plant pathogen, we grew a population of 15 isolates of Botrytis cinerea from throughout the world, under a variety of in vitro and in planta conditions. Under in planta conditions, phenotypic differences between the isolates were determined by the combination of genotypic variation within the pathogen and environmental variation. In contrast, phenotypic differences between the isolates under in vitro conditions were predominantly determined by genetic variation in the pathogen. Using a correlation network approach, we link the phenotypic variation under in vitro experimental conditions to phenotypic variation during plant infection. This study indicates that there is a high level of phenotypic variation within B. cinerea that is controlled by a mixture of genetic variation, environment, and genotype × environment. This argues that future experiments into the pathogenicity of B. cinerea must account for the genetic and environmental variation within the pathogen to better sample the potential phenotypic space of the pathogen. PMID:26828401

  4. Purification and serological analyses of tospoviral nucleocapsid proteins expressed by Zucchini yellow mosaic virus vector in squash.

    PubMed

    Chen, Tsung-Chi; Hsu, Hei-Ti; Jain, Rekesh K; Huang, Ching-Wen; Lin, Chen-Hsuan; Liu, Fang-Lin; Yeh, Shyi-Dong

    2005-11-01

    A plant viral vector engineered from an in vivo infectious clone of Zucchini yellow mosaic virus (ZYMV) was used to express the nucleocapsid proteins (NPs) of tospoviruses in planta. The open reading frames (ORFs) of NPs of different serogroups of tospoviruses, including Tomato spotted wilt virus, Impatiens necrotic spot virus, Watermelon silver mottle virus, Peanut bud necrosis virus, and Watermelon bud necrosis virus (WBNV), were in frame inserted in between the P1 and HC-Pro genes of the ZYMV vector. Six histidine residues and an NIa protease cleavage site were added at the C-terminal region of the inserts to facilitate purification and process of free form of the expressed NPs, respectively. Approximately 1.2-2.5 mg/NPs 100 g tissues were purified from leaf extracts of zucchini squash. The expressed WBNV NP was used as an immunogen for the production of highly specific polyclonal antisera and monoclonal antibodies. The procedure provides a convenient and fast way for production of large quantities of pure NPs of tospoviruses in planta. The system also has a potential for production of any proteins of interest in cucurbits. PMID:15992936

  5. Mutations in the NB-ARC Domain of I-2 That Impair ATP Hydrolysis Cause Autoactivation1[OA

    PubMed Central

    Tameling, Wladimir I.L.; Vossen, Jack H.; Albrecht, Mario; Lengauer, Thomas; Berden, Jan A.; Haring, Michel A.; Cornelissen, Ben J.C.; Takken, Frank L.W.

    2006-01-01

    Resistance (R) proteins in plants confer specificity to the innate immune system. Most R proteins have a centrally located NB-ARC (nucleotide-binding adaptor shared by APAF-1, R proteins, and CED-4) domain. For two tomato (Lycopersicon esculentum) R proteins, I-2 and Mi-1, we have previously shown that this domain acts as an ATPase module that can hydrolyze ATP in vitro. To investigate the role of nucleotide binding and hydrolysis for the function of I-2 in planta, specific mutations were introduced in conserved motifs of the NB-ARC domain. Two mutations resulted in autoactivating proteins that induce a pathogen-independent hypersensitive response upon expression in planta. These mutant forms of I-2 were found to be impaired in ATP hydrolysis, but not in ATP binding, suggesting that the ATP- rather than the ADP-bound state of I-2 is the active form that triggers defense signaling. In addition, upon ADP binding, the protein displayed an increased affinity for ADP suggestive of a change of conformation. Based on these data, we propose that the NB-ARC domain of I-2, and likely of related R proteins, functions as a molecular switch whose state (on/off) depends on the nucleotide bound (ATP/ADP). PMID:16489136

  6. Phenylcoumaran Benzylic Ether Reductase Prevents Accumulation of Compounds Formed under Oxidative Conditions in Poplar Xylem[W

    PubMed Central

    Niculaes, Claudiu; Morreel, Kris; Kim, Hoon; Lu, Fachuang; McKee, Lauren S.; Ivens, Bart; Haustraete, Jurgen; Vanholme, Bartel; Rycke, Riet De; Hertzberg, Magnus; Fromm, Jorg; Bulone, Vincent; Polle, Andrea; Ralph, John; Boerjan, Wout

    2014-01-01

    Phenylcoumaran benzylic ether reductase (PCBER) is one of the most abundant proteins in poplar (Populus spp) xylem, but its biological role has remained obscure. In this work, metabolite profiling of transgenic poplar trees downregulated in PCBER revealed both the in vivo substrate and product of PCBER. Based on mass spectrometry and NMR data, the substrate was identified as a hexosylated 8–5-coupling product between sinapyl alcohol and guaiacylglycerol, and the product was identified as its benzyl-reduced form. This activity was confirmed in vitro using a purified recombinant PCBER expressed in Escherichia coli. Assays performed on 20 synthetic substrate analogs revealed the enzyme specificity. In addition, the xylem of PCBER-downregulated trees accumulated over 2000-fold higher levels of cysteine adducts of monolignol dimers. These compounds could be generated in vitro by simple oxidative coupling assays involving monolignols and cysteine. Altogether, our data suggest that the function of PCBER is to reduce phenylpropanoid dimers in planta to form antioxidants that protect the plant against oxidative damage. In addition to describing the catalytic activity of one of the most abundant enzymes in wood, we provide experimental evidence for the antioxidant role of a phenylpropanoid coupling product in planta. PMID:25238751

  7. Root growth regulation and gravitropism in maize roots does not require the epidermis

    NASA Technical Reports Server (NTRS)

    Bjorkman, T.; Cleland, R. E.

    1991-01-01

    We have earlier published observations showing that endogenous alterations in growth rate during gravitropism in maize roots (Zea mays L.) are unaffected by the orientation of cuts which remove epidermal and cortical tissue in the growing zone (Bjorkman and Cleland, 1988, Planta 176, 513-518). We concluded that the epidermis and cortex are not essential for transporting a growth-regulating signal in gravitropism or straight growth, nor for regulating the rate of tissue expansion. This conclusion has been challenged by Yang et al. (1990, Planta 180, 530-536), who contend that a shallow girdle around the entire perimeter of the root blocks gravitropic curvature and that this inhibition is the result of a requirement for epidermal cells to transport the growth-regulating signal. In this paper we demonstrate that the entire epidermis can be removed without blocking gravitropic curvature and show that the position of narrow girdles does not affect the location of curvature. We therefore conclude that the epidermis is not required for transport of a growth-regulating substance from the root cap to the growing zone, nor does it regulate the growth rate of the elongating zone of roots.

  8. Characterization of Coffee ringspot virus-Lavras: A model for an emerging threat to coffee production and quality

    SciTech Connect

    Ramalho, T.O.; Figueira, A.R.; Sotero, A.J.; Wang, R.; Geraldino Duarte, P.S.; Farman, M.; Goodin, M.M.

    2014-09-15

    The emergence of viruses in Coffee (Coffea arabica and Coffea canephora), the most widely traded agricultural commodity in the world, is of critical concern. The RNA1 (6552 nt) of Coffee ringspot virus is organized into five open reading frames (ORFs) capable of encoding the viral nucleocapsid (ORF1p), phosphoprotein (ORF2p), putative cell-to-cell movement protein (ORF3p), matrix protein (ORF4p) and glycoprotein (ORF5p). Each ORF is separated by a conserved intergenic junction. RNA2 (5945 nt), which completes the bipartite genome, encodes a single protein (ORF6p) with homology to RNA-dependent RNA polymerases. Phylogenetic analysis of L protein sequences firmly establishes CoRSV as a member of the recently proposed Dichorhavirus genus. Predictive algorithms, in planta protein expression, and a yeast-based nuclear import assay were used to determine the nucleophillic character of five CoRSV proteins. Finally, the temperature-dependent ability of CoRSV to establish systemic infections in an initially local lesion host was quantified. - Highlights: • We report genome sequence determination for Coffee ringspot virus (CoRSV). • CoRSV should be considered a member of the proposed Dichorhavirus genus. • We report temperature-dependent systemic infection of an initially local lesion host. • We report in planta protein and localization data for five CoRSV proteins. • In silico predictions of the CoRSV proteins were validated using in vivo assays.

  9. The Azorhizobium caulinodans nifA gene: identification of upstream-activating sequences including a new element, the 'anaerobox'.

    PubMed Central

    Nees, D W; Stein, P A; Ludwig, R A

    1988-01-01

    From nucleotide sequencing analyses, the A. caulinodans nifA gene seems to be under dual control by the Ntr (in response to available N) and Fnr (in response to available O2) transcriptional activation/repression systems. Because it fixes N2 in two contexts, the Ntr system might regulate A. caulinodans nif gene expression ex planta, while the Fnr system might similarly regulate in planta. As nifA upstream-activating elements, we have identified: (i) a gpNifA binding site allowing autogenous nifA regulation, (ii) an Ntr-dependent transcription start, presumably the target of gpNifA activation, and (iii) an "anaerobox" tetradecameric nucleotide sequence that is precisely conserved among O2 regulated enteric bacterial genes controlled by the gpFnr transcriptional activator. Because it is precisely positioned upstream of enteric bacterial transcriptional starts, the "anaerobox" sequence may constitute the gpFnr DNA binding site. If so, then a second, Ntr-independent nifA transcription start may exist. We have also deduced the A. caulinodans nifA open reading frame and have compared the gene product (gpNifA) with those of other N2-fixing organisms. These proteins exhibit strongly conserved motifs: (i) sites conserved among ATP-binding proteins, (ii) an interdomain linker region, and (iii) a C-terminal alpha-helix-turn-alpha-helix DNA binding site. PMID:3186446

  10. Overexpression of antimicrobial lytic peptides protects grapevine from Pierce's disease under greenhouse but not field conditions.

    PubMed

    Li, Zhijian T; Hopkins, Donald L; Gray, Dennis J

    2015-10-01

    Pierce's disease (PD) caused by Xylella fastidiosa prevents cultivation of grapevine (Vitis vinifera) and susceptible hybrids in the southeastern United States and poses a major threat to the grape industry of California and Texas. Genetic resistance is the only proven control of X. fastidiosa. Genetic engineering offers an alternative to heretofore ineffective conventional breeding in order to transfer only PD resistance traits into elite cultivars. A synthetic gene encoding lytic peptide LIMA-A was introduced into V. vinifera and a Vitis hybrid to assess in planta inhibition of X. fastidiosa. Over 1050 independent transgenic plant lines were evaluated in the greenhouse, among which nine lines were selected and tested under naturally-inoculated field conditions. These selected plant lines in the greenhouse remain disease-free for 10 years, to date, even with multiple manual pathogen inoculations. However, all these lines in the field, including a grafted transgenic rootstock, succumbed to PD within 7 years. We conclude that in planta production of antimicrobial lytic peptides does not provide durable PD resistance to grapevine under field conditions. PMID:25894660

  11. The C-glycosylation of flavonoids in cereals.

    PubMed

    Brazier-Hicks, Melissa; Evans, Kathryn M; Gershater, Markus C; Puschmann, Horst; Steel, Patrick G; Edwards, Robert

    2009-07-01

    Flavonoids normally accumulate in plants as O-glycosylated derivatives, but several species, including major cereal crops, predominantly synthesize flavone-C-glycosides, which are stable to hydrolysis and are biologically active both in planta and as dietary components. An enzyme (OsCGT) catalyzing the UDP-glucose-dependent C-glucosylation of 2-hydroxyflavanone precursors of flavonoids has been identified and cloned from rice (Oryza sativa ssp. indica), with a similar protein characterized in wheat (Triticum aestivum L.). OsCGT is a 49-kDa family 1 glycosyltransferase related to known O-glucosyltransferases. The recombinant enzyme C-glucosylated 2-hydroxyflavanones but had negligible O-glucosyltransferase activity with flavonoid acceptors. Enzyme chemistry studies suggested that OsCGT preferentially C-glucosylated the dibenzoylmethane tautomers formed in equilibrium with 2-hydroxyflavanones. The resulting 2-hydroxyflavanone-C-glucosides were unstable and spontaneously dehydrated in vitro to yield a mixture of 6C- and 8C-glucosyl derivatives of the respective flavones. In contrast, in planta, only the respective 6C-glucosides accumulated. Consistent with this selectivity in glycosylation product, a dehydratase activity that preferentially converted 2-hydroxyflavanone-C-glucosides to the corresponding flavone-6C-glucosides was identified in both rice and wheat. Our results demonstrate that cereal crops synthesize C-glucosylated flavones through the concerted action of a CGT and dehydratase acting on activated 2-hydroxyflavanones, as an alternative means of generating flavonoid metabolites. PMID:19411659

  12. The Anti-Phytophthora Effect of Selected Potato-Associated Pseudomonas Strains: From the Laboratory to the Field.

    PubMed

    Guyer, Anouk; De Vrieze, Mout; Bönisch, Denise; Gloor, Ramona; Musa, Tomke; Bodenhausen, Natacha; Bailly, Aurélien; Weisskopf, Laure

    2015-01-01

    Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late blight is controlled by repeated applications of copper-based products, which negatively impact the environment. To find alternative solutions for late blight management, we have previously isolated a large collection of bacteria from the phyllosphere and the rhizosphere of potatoes. Here we report the antagonistic potential of these strains when co-cultivated with P. infestans as well as with other potato pathogens. We then focused on three Pseudomonas strains and compared their protective impact against late blight to that of well-known biocontrol strains in planta using a high-throughput leaf disk assay with automated picture analysis. When sprayed on the leaves of potatoes in the greenhouse, the strains were able to survive for at least 15 days. Under field conditions, populations decreased faster but all tested strains could still be retrieved after 8 days. The most active strain in vitro, P. chlororaphis R47, was also the best protectant on leaf disks from plants grown in the greenhouse experiment, but its protection potential could not be verified in the field due to unfavorable infection conditions. However, its protective effect against P. infestans in planta, its survival in the phyllosphere as well as its ability to colonize the potato rhizosphere in very high population densities, suggest a potential for field application, e.g., in the form of tuber treatment or leaf spray. PMID:26640460

  13. Arabidopsis ABCG14 protein controls the acropetal translocation of root-synthesized cytokinins

    NASA Astrophysics Data System (ADS)

    Zhang, Kewei; Novak, Ondrej; Wei, Zhaoyang; Gou, Mingyue; Zhang, Xuebin; Yu, Yong; Yang, Huijun; Cai, Yuanheng; Strnad, Miroslav; Liu, Chang-Jun

    2014-02-01

    Cytokinins are a major group of phytohormones regulating plant growth, development and stress responses. However, in contrast to the well-defined polar transport of auxins, the molecular basis of cytokinin transport is poorly understood. Here we show that an ATP-binding cassette transporter in Arabidopsis, AtABCG14, is essential for the acropetal (root to shoot) translocation of the root-synthesized cytokinins. AtABCG14 is expressed primarily in the pericycle and stelar cells of roots. Knocking out AtABCG14 strongly impairs the translocation of trans-zeatin (tZ)-type cytokinins from roots to shoots, thereby affecting the plant’s growth and development. AtABCG14 localizes to the plasma membrane of transformed cells. In planta feeding of C14 or C13-labelled tZ suggests that it acts as an efflux pump and its presence in the cells directly correlates with the transport of the fed cytokinin. Therefore, AtABCG14 is a transporter likely involved in the long-distance translocation of cytokinins in planta.

  14. Mitogen-activated protein kinase signal transduction and DNA repair network are involved in aluminum-induced DNA damage and adaptive response in root cells of Allium cepa L.

    PubMed Central

    Panda, Brahma B.; Achary, V. Mohan M.

    2014-01-01

    In the current study, we studied the role of signal transduction in aluminum (Al3+)-induced DNA damage and adaptive response in root cells of Allium cepa L. The root cells in planta were treated with Al3+ (800 μM) for 3 h without or with 2 h pre-treatment of inhibitors of mitogen-activated protein kinase (MAPK), and protein phosphatase. Also, root cells in planta were conditioned with Al3+ (10 μM) for 2 h and then subjected to genotoxic challenge of ethyl methane sulfonate (EMS; 5 mM) for 3 h without or with the pre-treatment of the aforementioned inhibitors as well as the inhibitors of translation, transcription, DNA replication and repair. At the end of treatments, roots cells were assayed for cell death and/or DNA damage. The results revealed that Al3+ (800 μM)-induced significant DNA damage and cell death. On the other hand, conditioning with low dose of Al3+ induced adaptive response conferring protection of root cells from genotoxic stress caused by EMS-challenge. Pre-treatment of roots cells with the chosen inhibitors prior to Al3+-conditioning prevented or reduced the adaptive response to EMS genotoxicity. The results of this study suggested the involvement of MAPK and DNA repair network underlying Al-induced DNA damage and adaptive response to genotoxic stress in root cells of A. cepa. PMID:24926302

  15. Characterization of IRE1 ribonuclease-mediated mRNA decay in plants using transient expression analyses in rice protoplasts.

    PubMed

    Hayashi, Shimpei; Wakasa, Yuhya; Ozawa, Kenjirou; Takaiwa, Fumio

    2016-06-01

    In some eukaryotes, endoplasmic reticulum (ER) stress induces regulated inositol-requiring enzyme 1 (IRE1)-dependent decay (RIDD) of mRNAs. Recently, the expression levels of the mRNAs encoding some secretory proteins were reported to be downregulated by RIDD in the vegetative tissues of plants. However, the characteristics of plant RIDD have been insufficiently investigated due to difficulty of in planta analyses. Here, the RIDD susceptibilities of various mRNAs that are difficult to analyze in planta were examined using transient expression analyses of rice protoplasts. In this system, the mRNAs encoding three rice seed storage proteins (SSPs) - namely α-globulin, 16-kDa prolamin and 10-kDa prolamin - were downregulated in response to ER stress. The rapid ER stress-induced degradation of these mRNAs was repressed in cells in which the ribonuclease activity of IRE1 was specifically abolished by genome editing, suggesting that the mRNAs encoding certain SSPs are strong targets of RIDD. Furthermore, we investigated whether these RIDD targets are substrates of the IRE1 ribonuclease using a recombinant IRE1 protein, and identified candidate IRE1-mediated cleavage sites. Overall, the results demonstrate the existence of a post-transcriptional mechanism of regulation of SSPs, and illustrate the basic and multifaceted characteristics of RIDD in higher plants. PMID:26831622

  16. The Anti-Phytophthora Effect of Selected Potato-Associated Pseudomonas Strains: From the Laboratory to the Field

    PubMed Central

    Guyer, Anouk; De Vrieze, Mout; Bönisch, Denise; Gloor, Ramona; Musa, Tomke; Bodenhausen, Natacha; Bailly, Aurélien; Weisskopf, Laure

    2015-01-01

    Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late blight is controlled by repeated applications of copper-based products, which negatively impact the environment. To find alternative solutions for late blight management, we have previously isolated a large collection of bacteria from the phyllosphere and the rhizosphere of potatoes. Here we report the antagonistic potential of these strains when co-cultivated with P. infestans as well as with other potato pathogens. We then focused on three Pseudomonas strains and compared their protective impact against late blight to that of well-known biocontrol strains in planta using a high-throughput leaf disk assay with automated picture analysis. When sprayed on the leaves of potatoes in the greenhouse, the strains were able to survive for at least 15 days. Under field conditions, populations decreased faster but all tested strains could still be retrieved after 8 days. The most active strain in vitro, P. chlororaphis R47, was also the best protectant on leaf disks from plants grown in the greenhouse experiment, but its protection potential could not be verified in the field due to unfavorable infection conditions. However, its protective effect against P. infestans in planta, its survival in the phyllosphere as well as its ability to colonize the potato rhizosphere in very high population densities, suggest a potential for field application, e.g., in the form of tuber treatment or leaf spray. PMID:26640460

  17. Sugars as hydroxyl radical scavengers: proof-of-concept by studying the fate of sucralose in Arabidopsis.

    PubMed

    Matros, Andrea; Peshev, Darin; Peukert, Manuela; Mock, Hans-Peter; Van den Ende, Wim

    2015-06-01

    Substantial formation of reactive oxygen species (ROS) is inevitable in aerobic life forms. Due to their extremely high reactivity and short lifetime, hydroxyl radicals are a special case, because cells have not developed enzymes to detoxify these most dangerous ROS. Thus, scavenging of hydroxyl radicals may only occur by accumulation of higher levels of simple organic compounds. Previous studies have demonstrated that plant-derived sugars show hydroxyl radical scavenging capabilities during Fenton reactions with Fe(2+) and hydrogen peroxide in vitro, leading to formation of less detrimental sugar radicals that may be subject of regeneration to non-radical carbohydrates in vivo. Here, we provide further evidence for the occurrence of such radical reactions with sugars in planta, by following the fate of sucralose, an artificial analog of sucrose, in Arabidopsis tissues. The expected sucralose recombination and degradation products were detected in both normal and stressed plant tissues. Oxidation products of endogenous sugars were also assessed in planta for Arabidopsis and barley, and were shown to increase in abundance relative to the non-oxidized precursor during oxidative stress conditions. We concluded that such non-enzymatic reactions with hydroxyl radicals form an integral part of plant antioxidant mechanisms contributing to cellular ROS homeostasis, and may be more important than generally assumed. This is discussed in relation to the recently proposed roles for Fe(2+) and hydrogen peroxide in processes leading to the origin of metabolism and the origin of life. PMID:25891826

  18. A Phytophthora infestans RXLR effector targets plant PP1c isoforms that promote late blight disease.

    PubMed

    Boevink, Petra C; Wang, Xiaodan; McLellan, Hazel; He, Qin; Naqvi, Shaista; Armstrong, Miles R; Zhang, Wei; Hein, Ingo; Gilroy, Eleanor M; Tian, Zhendong; Birch, Paul R J

    2016-01-01

    Plant pathogens deliver effectors to alter host processes. Knowledge of how effectors target and manipulate host proteins is critical to understand crop disease. Here, we show that in planta expression of the RXLR effector Pi04314 enhances leaf colonization by Phytophthora infestans via activity in the host nucleus and attenuates induction of jasmonic and salicylic acid-responsive genes. Pi04314 interacts with three host protein phosphatase 1 catalytic (PP1c) isoforms, causing their re-localization from the nucleolus to the nucleoplasm. Re-localization of PP1c-1 also occurs during infection and is dependent on an R/KVxF motif in the effector. Silencing the PP1c isoforms or overexpression of a phosphatase-dead PP1c-1 mutant attenuates infection, demonstrating that host PP1c activity is required for disease. Moreover, expression of PP1c-1mut abolishes enhanced leaf colonization mediated by in planta Pi04314 expression. We argue that PP1c isoforms are susceptibility factors forming holoenzymes with Pi04314 to promote late blight disease. PMID:26822079

  19. Cellulose binding domains of a Phytophthora cell wall protein are novel pathogen-associated molecular patterns.

    PubMed

    Gaulin, Elodie; Dram, Nani; Lafitte, Claude; Torto-Alalibo, Trudy; Martinez, Yves; Ameline-Torregrosa, Carine; Khatib, Moustafa; Mazarguil, Honor; Villalba-Mateos, Franois; Kamoun, Sophien; Mazars, Christian; Dumas, Bernard; Bottin, Arnaud; Esquerr-Tugay, Marie-Thrse; Rickauer, Martina

    2006-07-01

    The cellulose binding elicitor lectin (CBEL) from Phytophthora parasitica nicotianae contains two cellulose binding domains (CBDs) belonging to the Carbohydrate Binding Module1 family, which is found almost exclusively in fungi. The mechanism by which CBEL is perceived by the host plant remains unknown. The role of CBDs in eliciting activity was investigated using modified versions of the protein produced in Escherichia coli or synthesized in planta through the potato virus X expression system. Recombinant CBEL produced by E. coli elicited necrotic lesions and defense gene expression when injected into tobacco (Nicotiana tabacum) leaves. CBEL production in planta induced necrosis. Site-directed mutagenesis on aromatic amino acid residues located within the CBDs as well as leaf infiltration assays using mutated and truncated recombinant proteins confirmed the importance of intact CBDs to induce defense responses. Tobacco and Arabidopsis thaliana leaf infiltration assays using synthetic peptides showed that the CBDs of CBEL are essential and sufficient to stimulate defense responses. Moreover, CBEL elicits a transient variation of cytosolic calcium levels in tobacco cells but not in protoplasts. These results define CBDs as a novel class of molecular patterns in oomycetes that are targeted by the innate immune system of plants and might act through interaction with the cell wall. PMID:16766692

  20. A mutation in the tomato DDB1 gene affects cell and chloroplast compartment size and CDT1 transcript

    PubMed Central

    Caspi, Nili; Levin, Ilan; Chamovitz, Daniel A

    2008-01-01

    Fruits harvested from tomato (Solanum lycopersicum) plants carrying mutations at the DAMAGED DNA BINDING PROTEIN 1 gene (SlDDB1; hp-1 and hp-1w) are characterized by significantly elevated levels of lycopene and several other phytonutrients. We hypothesize that the pleotropic effect on mutant Slddb1 are some general function of DDB1 protein on cell growth. The main objective of this research was to carry out functional analysis of the mutant SlDDB1 alleles both in-planta and ex-planta in comparison to their normal counterparts. Our major results indicate that: mutant Slddb1 seedlings exhibited delayed growth and smaller cell size, greater chloroplast density, smaller chloroplasts and higher concentration of chlorophyll. Cotyledons cells of Slddb1 mutant also displayed abnormal stomatal pattern, reduced content of CDT1 transcript and altered response to cytokinin. Some of these observations were previously described to be connected to defects in cell cycle control. Our results, coupled with former studies, also suggest that the CDD complex (composed of DDB1, DET1 and COP10) mediate the effect of light and cytokinin activity by possibly regulating the replication licensing factor CDT1 thus affecting both cell size and plastid multiplication. PMID:19513255

  1. Inhibition of Phytophthora parasitica and P. capsici by Silver Nanoparticles Synthesized Using Aqueous Extract of Artemisia absinthium.

    PubMed

    Ali, Mohammad; Kim, Bosung; Belfield, Kevin D; Norman, David; Brennan, Mary; Ali, Gul Shad

    2015-09-01

    Application of nanoparticles for controlling plant pathogens is a rapidly emerging area in plant disease management, and nanoparticles synthesis methods that are economical and ecofriendly are extensively investigated. In this project, we investigated the potential of silver nanoparticles (AgNPs) synthesized with aqueous extract of Artemisia absinthium against several Phytophthora spp., which cause many economically important crop diseases. In in vitro dose-response tests conducted in microtiter plates, 10 µg ml⁻¹ of AgNPs inhibited mycelial growth of P. parasitica, P. infestans, P. palmivora, P. cinnamomi, P. tropicalis, P. capsici, and P. katsurae. Detailed in vitro dose-response analyses conducted with P. parasitica and P. capsici revealed that AgNPs synthesized with A. absinthium extract were highly potent (IC50: 2.1 to 8.3 µg ml⁻¹) and efficacious (100%) in inhibiting mycelial growth, zoospore germination, germ tube elongation, and zoospore production. Interestingly, AgNP treatment accelerated encystment of zoospores. Consistent with in vitro results, in planta experiments conducted in a greenhouse revealed that AgNP treatments prevented Phytophthora infection and improved plant survival. Moreover, AgNP in in planta experiments did not produce any adverse effects on plant growth. These investigations provide a simple and economical method for controlling Phytophthora with AgNP without affecting normal plant physiology. PMID:25871856

  2. Hyaloperonospora arabidopsidis ATR1 effector is a repeat protein with distributed recognition surfaces

    PubMed Central

    Chou, Seemay; Krasileva, Ksenia V.; Holton, James M.; Steinbrenner, Adam D.; Alber, Tom; Staskawicz, Brian J.

    2011-01-01

    The in planta association of the Hyaloperonospora arabidopsidis effector ATR1 with the cognate Arabidopsis thaliana RPP1 immune receptor activates a disease-resistance signaling pathway that inhibits pathogen growth. To define the molecular events specifying effector recognition by RPP1, we determined the crystal structure of ATR1 and assayed in planta the effects of surface polymorphisms that are critical to activating plant immunity. ATR1 adopts an elongated, all-helical, two-domain, seahorse-like structure with an overall architecture unlike any previously described fold. Structural comparisons highlight a tandemly duplicated, five-helix motif in the C-terminal domain that creates a structural framework for rapid diversification. Identification and mapping of critical recognition sites suggest that ATR1 detection by the RPP1 resistance protein is mediated by several distinct protein surfaces that allow the effectors to escape recognition through diverse surface polymorphisms. ATR1 gain-of-recognition mutants demonstrate that multiple amino acid substitutions are necessary for recognition and that surface polymorphisms exert additive effects. These results suggest that ATR1 is a modular repeat protein belonging to an ancient family of oomycete effectors that rapidly evolves to escape host detection and adopt diverse virulence functions. PMID:21788488

  3. Shaping bacterial symbiosis with legumes by experimental evolution.

    PubMed

    Marchetti, Marta; Jauneau, Alain; Capela, Delphine; Remigi, Philippe; Gris, Carine; Batut, Jacques; Masson-Boivin, Catherine

    2014-09-01

    Nitrogen-fixing symbionts of legumes have appeared after the emergence of legumes on earth, approximately 70 to 130 million years ago. Since then, symbiotic proficiency has spread to distant genera of α- and β-proteobacteria, via horizontal transfer of essential symbiotic genes and subsequent recipient genome remodeling under plant selection pressure. To tentatively replay rhizobium evolution in laboratory conditions, we previously transferred the symbiotic plasmid of the Mimosa symbiont Cupriavidus taiwanensis in the plant pathogen Ralstonia solanacearum, and selected spontaneous nodulating variants of the chimeric Ralstonia sp. using Mimosa pudica as a trap. Here, we pursued the evolution experiment by submitting two of the rhizobial drafts to serial ex planta-in planta (M. pudica) passages that may mimic alternating of saprophytic and symbiotic lives of rhizobia. Phenotyping 16 cycle-evolved clones showed strong and parallel evolution of several symbiotic traits (i.e., nodulation competitiveness, intracellular infection, and bacteroid persistence). Simultaneously, plant defense reactions decreased within nodules, suggesting that the expression of symbiotic competence requires the capacity to limit plant immunity. Nitrogen fixation was not acquired in the frame of this evolutionarily short experiment, likely due to the still poor persistence of final clones within nodules compared with the reference rhizobium C. taiwanensis. Our results highlight the potential of experimental evolution in improving symbiotic proficiency and for the elucidation of relationship between symbiotic capacities and elicitation of immune responses. PMID:25105803

  4. Characterization of VuMATE1 Expression in Response to Iron Nutrition and Aluminum Stress Reveals Adaptation of Rice Bean (Vigna umbellata) to Acid Soils through Cis Regulation

    PubMed Central

    Liu, Meiya; Xu, Jiameng; Lou, Heqiang; Fan, Wei; Yang, Jianli; Zheng, Shaojian

    2016-01-01

    Rice bean (Vigna umbellata) VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acid soils where Al stress imposed but Fe deficiency pressure released. PMID:27148333

  5. Extracellular peptidases of the cereal pathogen Fusarium graminearum

    PubMed Central

    Lowe, Rohan G. T.; McCorkelle, Owen; Bleackley, Mark; Collins, Christine; Faou, Pierre; Mathivanan, Suresh; Anderson, Marilyn

    2015-01-01

    The plant pathogenic fungus Fusarium graminearum (Fgr) creates economic and health risks in cereals agriculture. Fgr causes head blight (or scab) of wheat and stalk rot of corn, reducing yield, degrading grain quality, and polluting downstream food products with mycotoxins. Fungal plant pathogens must secrete proteases to access nutrition and to breakdown the structural protein component of the plant cell wall. Research into the proteolytic activity of Fgr is hindered by the complex nature of the suite of proteases secreted. We used a systems biology approach comprising genome analysis, transcriptomics and label-free quantitative proteomics to characterize the peptidases deployed by Fgr during growth. A combined analysis of published microarray transcriptome datasets revealed seven transcriptional groupings of peptidases based on in vitro growth, in planta growth, and sporulation behaviors. A high resolution mass spectrometry-based proteomics analysis defined the extracellular proteases secreted by F. graminearum. A meta-classification based on sequence characters and transcriptional/translational activity in planta and in vitro provides a platform to develop control strategies that target Fgr peptidases. PMID:26635820

  6. Mechanosensitive channels: feeling tension in a world under pressure

    PubMed Central

    Peyronnet, Rémi; Tran, Daniel; Girault, Tiffanie; Frachisse, Jean-Marie

    2014-01-01

    Plants, like other organisms, are facing multiple mechanical constraints generated both in their tissues and by the surrounding environments. They need to sense and adapt to these forces throughout their lifetimes. To do so, different mechanisms devoted to force transduction have emerged. Here we focus on fascinating proteins: the mechanosensitive (MS) channels. Mechanosensing in plants has been described for centuries but the molecular identification of MS channels occurred only recently. This review is aimed at plant biologists and plant biomechanists who want to be introduced to MS channel identity, how they work and what they might do in planta? In this review, electrophysiological properties, regulations, and functions of well-characterized MS channels belonging to bacteria and animals are compared with those of plants. Common and specific properties are discussed. We deduce which tools and concepts from animal and bacterial fields could be helpful for improving our understanding of plant mechanotransduction. MS channels embedded in their plasma membrane are sandwiched between the cell wall and the cytoskeleton. The consequences of this peculiar situation are analyzed and discussed. We also stress how important it is to probe mechanical forces at cellular and subcellular levels in planta in order to reveal the intimate relationship linking the membrane with MS channel activity. Finally we will propose new tracks to help to reveal their physiological functions at tissue and plant levels. PMID:25374575

  7. Functional Characterization and Substrate Promiscuity of UGT71 Glycosyltransferases from Strawberry (Fragaria × ananassa).

    PubMed

    Song, Chuankui; Gu, Le; Liu, Jingyi; Zhao, Shuai; Hong, Xiaotong; Schulenburg, Katja; Schwab, Wilfried

    2015-12-01

    Glycosylation determines the complexity and diversity of plant natural products. To characterize fruit ripening-related UDP-dependent glycosyltransferases (UGTs) functionally in strawberry, we mined the publicly available Fragaria vesca genome sequence and found 199 putative UGT genes. Candidate UGTs whose expression levels were strongly up-regulated during fruit ripening were cloned from F.×ananassa and six were successfully expressed in Escherichia coli and biochemically characterized. UGT75T1 showed very strict substrate specificity and glucosylated only galangin out of 33 compounds. The other recombinant enzymes exhibited broad substrate tolerance, accepting numerous flavonoids, hydroxycoumarins, naphthols and the plant hormone, (+)-S-abscisic acid (ABA). UGT71W2 showed the highest activity towards 1-naphthol, while UGT71A33, UGT71A34a/b and UGT71A35 preferred 3-hydroxycoumarin and formed 3- and 7-O-glucosides as well as a diglucoside from flavonols. Screening of a strawberry physiological aglycone library identified kaempferol, quercetin, ABA and three unknown natural compounds as putative in planta substrates of UGT71A33, UGT71A34a and UGT71W2. Metabolite analyses of RNA interference (RNAi)-mediated silenced fruits demonstrated that UGT71W2 contributes to the glycosylation of flavonols, xenobiotics and, to a minor extent, of ABA, in planta. The study showed that both specialist and generalist UGTs were expressed during strawberry fruit ripening and the latter were probably not restricted to only one function in plants. PMID:26454881

  8. Cloning, characterization, and transcription of three laccase genes from Gaeumannomyces graminis var. tritici, the take-all fungus.

    PubMed

    Litvintseva, Anastasia P; Henson, Joan M

    2002-03-01

    Gaeumannomyces graminis var. tritici, a filamentous ascomycete, is an important root pathogen of cereals that causes take-all disease and results in severe crop losses worldwide. Previously we identified a polyphenol oxidase (laccase) secreted by the fungus when induced with copper. Here we report cloning and partial characterization of three laccase genes (LAC1, LAC2, and LAC3) from G. graminis var. tritici. Predicted polypeptides encoded by these genes had 38 to 42% amino acid sequence identity and had conserved copper-binding sites characteristic of laccases. The sequence of the LAC2 predicted polypeptide matched the N-terminal sequence of the secreted laccase that we purified in earlier studies. We also characterized expression patterns of these genes by reverse transcription-PCR. LAC1 was transcribed constitutively, and transcription of LAC2 was Cu inducible. All three genes were transcribed in planta; however, transcription of LAC3 was observed only in planta or in the presence of host (wheat) plant homogenate. PMID:11872481

  9. Extrapolate the Past... or Invent the Future

    ScienceCinema

    Vinod Khosla

    2010-01-08

    Berkeley Lab's Environmental Energy Technologies Division launches its Distinguished Lecturer series with a talk by Vinod Khosla, founder of Khosla Ventures, whose mission is to "assist great entre...  

  10. Poeme/Roman (Poem/Novel).

    ERIC Educational Resources Information Center

    Goldenstein, Jean-Pierre

    1988-01-01

    The characteristics of Natalie Sarrault's "Entre la vie et la mort" ("Between Life and Death") that blur the distinction between poetry and prose are examined, including wordplay, phonetic play, and graphic variations. (MSE)

  11. Extrapolate the Past... or Invent the Future

    SciTech Connect

    Vinod Khosla

    2008-10-14

    Berkeley Lab's Environmental Energy Technologies Division launches its Distinguished Lecturer series with a talk by Vinod Khosla, founder of Khosla Ventures, whose mission is to "assist great entre...  

  12. Giant Enhancement of Diffusion in a Tilted Egg-Carton Potential

    NASA Astrophysics Data System (ADS)

    Yang, Song; Jing-Dong, Bao

    2016-02-01

    Not Available Supported by the National Natural Science Foundation of China under Grant Nos 11575024 and 11175021, and the Plan of Beijing College Students' Scientific Research and EntrePrenurial Action under Grant No 105820.

  13. DEVELOPMENT OF SUPERIOR ENTRAINMENT SEPARATORS

    EPA Science Inventory

    An experimental and theoretical program was carried out to develop an improved design for entrainment separators for scrubbers. The problems of separation efficiency, suspended solids deposition and plugging of the entrainment separator were of primary concern. A pilot scale entr...

  14. Evaluation of a Voluntary Menu-Labeling Program in Full-Service Restaurants

    PubMed Central

    Leng, Kirsten

    2010-01-01

    Objectives. We assessed whether labeling restaurant menus with information on the nutrient content of menu items would cause customers to alter their ordering patterns. Methods. Six full-service restaurants in Pierce County, Washington, added nutrition information to their menus, and they provided data on entrée sales for 30 days before and 30 days after the information was added. We assessed the prelabeling versus postlabeling difference in nutrient content of entrées sold, and we surveyed restaurant patrons about whether they noticed the nutrition information and used it in their ordering. Results. The average postlabeling entrée sold contained about 15 fewer calories, 1.5 fewer grams of fat, and 45 fewer milligrams of sodium than did the average entrée sold before labeling. Seventy-one percent of patrons reported noticing the nutrition information; 20.4% reported ordering an entrée lower in calories as a result, and 16.5% reported ordering an entrée lower in fat as a result. Conclusions. The concentration of calorie reduction among 20.4% of patrons means that each calorie-reducing patron ordered about 75 fewer calories than they did before labeling. Thus, providing nutrition information on restaurant menus may encourage a subset of restaurant patrons to significantly alter their food choices. PMID:20395577

  15. Open-field host specificity test of Gratiana boliviana (Coleoptera: Chrysomelidae), a biological control agent of tropical soda apple (Solanaceae) in the United States

    SciTech Connect

    Gandolfo, D.; McKay, F.; Medal, J.C.; Cuda, J.P.

    2007-03-15

    An open-field experiment was conducted to assess the suitability of the South American leaf feeding beetle Gratiana boliviana Spaeth for biological control of Solanum viarum Dunal in the USA. An open-field test with eggplant, Solanum melongena L., was conducted on the campus of the University of Buenos Aires, Argentina, and a S. viarum control plot was established 40 km from the campus. One hundred adult beetles were released in each plot at the beginning of the experiment during the vegetative stage of the plants, and forty additional beetles were released in the S. melongena plot at the flowering stage. All the plants in each plot were checked twice a week and the number of adults, immatures, and eggs recorded. Results showed almost a complete rejection of eggplant by G. boliviana. No noticeable feeding damage was ever recorded on eggplant. The experiment was ended when the eggplants started to senesce or were severely damaged by whiteflies and spider mites. The results of this open-field experiment corroborate previous quarantine/laboratory host-specificity tests indicating that a host range expansion of G. boliviana to include eggplant is highly unlikely. Gratiana boliviana was approved for field release in May 2003 in the USA. To date, no non-target effects have been observed either on eggplant or native species of Solanum. (author) [Spanish] Una prueba de campo fue conducida para evaluar la especificidad del escarabajo suramericano defoliador Gratiana boliviana Spaeth para control biologico de Solanum viarum Dunal en los Estados Unidos. La prueba con berenjena se realizo en el campo experimental de la Universidad de Buenos Aires, Argentina, y una parcela control con S. viarum fue establecida a 40 km. Cien escarabajos adultos fueron liberados en cada parcela al inicio del experimento durante la fase vegetativa, y cuarenta escarabajos adicionales fueron liberados en la parcela de berenjena durante la floracion. Todas las plantas en cada parcela fueron inspeccionadas dos veces a la semana y el numero de adultos, larvas, y posturas fueron registrados. Resultados indicaron un casi completo rechazo de la berenjena por G. boliviana. Ningun dano visible de defoliacion en la berenjena fue detectado. Las pruebas concluyeron cuando las plantas de berenjena alcazaron su madurez o fueron severamente danadas por mosca blanca y acaros. Resultados corroboran previas pruebas de especificidad en laboratorio/cuarentena que indican que la berenjena no es un hospedero de G. boliviana y que la posibilidad de llegar a ser una plaga de este cultivo es muy remota. Gratiana boliviana fue aprobado para ser liberado en el campo en mayo del 2003. Ningun dano ha sido observado hasta la fecha a plantas no blanco. (author)

  16. Distinct colonization patterns and cDNA-AFLP transcriptome profiles in compatible and incompatible interactions between melon and different races of Fusarium oxysporum f. sp. melonis

    PubMed Central

    2011-01-01

    Background Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression are poorly understood. Resistance to races 1 and 2 is controlled by a single dominant gene, whereas only partial polygenic resistance to race 1,2 has been described. We carried out a large-scale cDNA-AFLP analysis to identify host genes potentially related to resistance and susceptibility as well as fungal genes associated with the infection process. At the same time, a systematic reisolation procedure on infected stems allowed us to monitor fungal colonization in compatible and incompatible host-pathogen combinations. Results Melon plants (cv. Charentais Fom-2), which are susceptible to race 1,2 and resistant to race 1, were artificially infected with a race 1 strain of FOM or one of two race 1,2 w strains. Host colonization of stems was assessed at 1, 2, 4, 8, 14, 16, 18 and 21 days post inoculation (dpi), and the fungus was reisolated from infected plants. Markedly different colonization patterns were observed in compatible and incompatible host-pathogen combinations. Five time points from the symptomless early stage (2 dpi) to obvious wilting symptoms (21 dpi) were considered for cDNA-AFLP analysis. After successful sequencing of 627 transcript-derived fragments (TDFs) differentially expressed in infected plants, homology searching retrieved 305 melon transcripts, 195 FOM transcripts expressed in planta and 127 orphan TDFs. RNA samples from FOM colonies of the three strains grown in vitro were also included in the analysis to facilitate the detection of in planta-specific transcripts and to identify TDFs differentially expressed among races/strains. Conclusion Our data suggest that resistance against FOM in melon involves only limited transcriptional changes, and that wilting symptoms could derive, at least partially, from an active plant response. We discuss the pathogen-derived transcripts expressed in planta during the infection process and potentially related to virulence functions, as well as transcripts that are differentially expressed between the two FOM races grown in vitro. These transcripts provide candidate sequences that can be further tested for their ability to distinguish between races. Sequence data from this article have been deposited in GenBank, Accession Numbers: HO867279-HO867981. PMID:21338485

  17. Gravisensing in Phycomyces

    NASA Astrophysics Data System (ADS)

    Schmidt, W.; Galland, P.

    The gravisusceptors of the single-celled fungus Phycomyces are locat ed in the apical growing zone of the sporangiophores. An aggregate of lipid globules generates buoy-ancy and floats "upwards", while octahedral protein crystals in the vacuoles sedment upon reorientation from vertical to horizontal (Schimek et al., 1999). Removal of the gravisusceptors by mutation or cold shock substantially impairs gravitropism. Both the protein crystals and also the lipid globules are associated with pterin- and flavin-like chromophores (Fries et al. 2002; Ogorodnikova et al. 2002). Photo hysiology indicates a role for these gravisusceptors also in lightp perception, probably the establishment of photogravitropic equilibrium. The gravitropic threshold for gravitropism was determined in a clinostat centrifuge. For the wild type it is near 2 x 10-2 x g; a mutant lacking the octahedral crystals displays an elevated threshold of about 10 - 1 x g. The negative gravitropism of the sporangiophores is associated with gravity-induced absorbance changes (GIACs) that can be detected by in-vivo spectroscopy with a ra- pid- scan spectrophotometer (RSS) or a novel micro-dual-wavelength spectrophoto- meter (MDWS) (Schmidt 1997). GIACs represent primary reactions of gravitropism that display a steady increment above 600 nm and a major maximum near 420 nm which probably indicate the reduction of a cytochrome (Schmidt, Galland 1999). GIACs were monitored during parabola flights in an airbus A300 (ESA campaign March 2002). Hypergravity (1.8 x g) elicited an instantaneous increase of the absor- bance at 460 nm, while microgravity (10-2 x g) elicited one at 600 nm. These absorbance changes critically depended on the light treatment prior to the gravistimulation. When dark adapted sporangiophores instead of light adapted ones (as above) were employed, then a sign reversal of the absorbance changes took place, i.e. hypergravity induced an increase at 600 nm and microgravity one at 460 nm. Fries V, T Krockert, F Grolig, P Galland (2002) J Plant Phys 159, 39-47 Ogorodnikova U, O Sineshchekov, P Galland (2002) J Plant Phys 159, 205-209 Schimek C, P Eibel, F Grolig, T Horie, T Ootaki, P Galland (1999) Planta 210, 132- 142 Schmidt W (1997) http://science.springer.de/ebo/abstract/1997/sla97_3.htm Schmidt W, P Galland (1999) Planta 208, 274-282. Schmidt W, P. Galland (2000) Planta 210, 848-852.

  18. Gravisensing in Phycomyces

    NASA Astrophysics Data System (ADS)

    Schmidt, W.; Galland, P.

    The gravisusceptors of the single-celled fungus Phycomyces are located in the apical growing zone of the sporangiophores. An aggregate of lipid globules generates buoy- ancy and floats "upwards", while octahedral protein crystals in the vacuoles sedment upon reorientation from vertical to horizontal (Schimek et al., 1999). Removal of the gravisusceptors by mutation or cold shock substantially impairs gravitr pism. Botho the protein crystals and also the lipid globules are associated with pterin- and flavin- like chromophores (Fries et al. 2002; Ogorodnikova et al. 2002). Photophysiology indicates a role for these gravisusceptors also in light perception, probably the estab- lishment of photogravitropic equili br i u m . The gravitropic threshold for gravitropism was determined in a clinostat centrifuge. For the wild type it is near 2 x 10- 2 x g; a mutant lacking the octahedral crystals dis- plays an elevated threshold of about 10-1 x g. The negative gravitropism of the sporangiophores is associated with gravity-induced absorbance changes (GIACs) that can be detected by in-vivo spectroscopy with a ra- pid-scan spectrophotometer (RSS) or a novel micro-dual-wavelength spectrophot o- meter (MDWS) (Schmidt 1997). GIACs represent primary reactions of gravitr pismo that display a steady increment above 600 nm and a major maximum near 420 nm which probably indicate the reduction of a cytochrome (Schmidt, Galland 1999). GIACs were monitored during parabola flights in an airbus A300 (ESA campaign March 2002). Hypergravity (1.8 x g) elicited an instantaneous increase of the absor- bance at 460 nm, while microgravity (10-2 x g) elicited one at 600 nm. These absor b- ance changes critically depended on the light treatment prior to the gravistimulation. When dark adapted sporangiophores instead of light adapted ones (as above) were employed, then a sign reversal of the absorbance changes took place, i.e. hypergrav- ity induced an increase at 600 nm and microgravity one at 460 nm. Fries V, T Krockert, F Grolig, P Galland (2002) J Plant Phys 159, 39 -4 7 Ogorodniko va U, O Sineshchekov, P Galland (2002) J Plant Phys 159, 205-209 Schimek C, P Eibel, F Grolig, T Horie, T Ootaki, P Galland (1999) Planta 210, 132-142 Schmidt W (1997) http://science.springer.de/ebo/abstract/1997/sla97_3.htm Schmidt W, P Galland (1999) Planta 208, 274-282. Schmidt W, P. Galland (2000) Planta 210, 848-852.

  19. Fruit and vegetable exposure in children is linked to the selection of a wider variety of healthy foods at school.

    PubMed

    Korinek, Elizabeth V; Bartholomew, John B; Jowers, Esbelle M; Latimer, Lara A

    2015-10-01

    Schools often offer healthy fruits and vegetables (FV) and healthy entrées. However, children may resist these efforts due to a lack of familiarity with the offerings. While numerous exposures with a food increase its liking, it may be that an exposure to a variety of FV at home leads to greater willingness to select other foods - even those that are unrelated to those eaten at home. As an initial test of this possibility, this study was designed to examine how self-reports of exposure and consumption of various FV were associated with the selection of FV and lunch entrées at school. Participants (n = 59) were a convenience sample of elementary children. A median split was used to place students into high- and low-exposure groups for self-reports of both exposure and consumption at home. The primary dependent variables were self-reports of selecting FV at school; the children's absolute and relative ratings of eight 'healthier' lunch entrées; and self-reports of selecting these entrées. These entrées were recently added to the school menu and, therefore, tended to be less familiar to children. Food ratings were collected through taste exposures conducted at school. Results indicate that children who reported more frequent exposure to FV at home consumed a wider variety of FV at school and were more likely to report selecting 'healthier' entrées at school lunch. These data suggest that exposure to, and the consumption of, a variety of FV may make children more willing to select a wider range of FV and other healthy entrées. PMID:23557428

  20. El rol de Ia colaboracion y el Modelo de Aprendizaje Basado en Proyectos (ABPr) mediante el lente de la Teoria de Actividad (CHAT): un estudio de caso con estudiantes de 9no grado

    NASA Astrophysics Data System (ADS)

    Delgado, Isabel C.

    Los modelos de eensenanza y aprendizaje constructivistas conceptualizan el aprendizaje como un proceso activo. El modelo de Aprendizaje Basado en Proyectos (ABPr) se distingue por una serie de componentes, entre los cuales se destaca el aspecto colaborativo y cooperativo como un reto al momento de su implantacion. Son pocas las investigaciones que se concentran en este aspecto del modelo. En este estudio, se analizaron las diversas interacciones que surgen durante la implantacion de una unidad curricular sobre el tema de Geologia de Puerto Rico, la cual se diseno con el modelo ABPr cuyo enfoque es orientacion a proyectos. Particularmente, se examinaron las interacciones sociales que surgen entre los pares y entre pares y docente durante el proceso de planificacion y desarrollo de los productos finales, al igual que las interacciones entre los estudiantes y el material didactico en estas etapas del modelo. La investigacion es de tipo cualitativo e incorpora como diseno el estudio de caso. Las diversas interacciones constituyen la unidad de analisis. En el estudio participaron 19 estudiantes de 9no grado, a quienes se organizaron en 5 grupos colaborativos por temas de interes (Pangea, Placas tectonicas, Volcanes, Tsunamis y Terremotos). Las tecnicas que se utilizaron para recopilar los datos fueron: observaciones participativas, grupos focales y analisis de documentos (cuadernos reflexivos y respuestas de los estudiantes a la pregunta central del proyecto). Para el analisis de los datos se aplico la teoria de actividad (CHAT) que concentra la unidad de analisis en la actividad humana en un contexto particular. Los resultados del estudio senalan que las interacciones entre pares, entre pares y docente, asi como entre estudiantes y material didactico son fundamentales en el proceso de aprendizaje. Una mayor interaccion entre pares durante las etapas de planificar y desarrollar los productos finales de la unidad, promue