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Sample records for acidic fens reveal

  1. Dynamics of organic and inorganic arsenic in the solution phase of an acidic fen in Germany

    Huang, J.-H.; Matzner, E.

    2006-04-01

    Wetland soils play a key role for the transformation of heavy metals in forested watersheds, influencing their mobility, and ecotoxicity. Our goal was to investigate the mechanisms of release from solid to solution phase, the mobility, and the transformation of arsenic species in a fen soil. In methanol-water extracts, monomethylarsonic acid, dimethylarsinic acid, trimethylarsine oxide, arsenobetaine, and two unknown organic arsenic species were found with concentrations up to 14 ng As g -1 at the surface horizon. Arsenate is the dominant species at the 0-30 cm depth, whereas arsenite predominated at the 30-70 cm depth. Only up to 2.2% of total arsenic in fen was extractable with methanol-water. In porewaters, depth gradient spatial variation of arsenic species, pH, redox potentials, and the other chemical parameters along the profile was observed in June together with high proportion of organic arsenic species (up to 1.2 μg As L -1, 70% of total arsenic). Tetramethylarsonium ion and an unknown organic arsenic species were additionally detected in porewaters at deeper horizons. In comparison, the arsenic speciation in porewaters in April was homogeneous with depth and no organic arsenic species were found. Thus, the occurrence of microbial methylation of arsenic in fen was demonstrated for the first time. The 10 times elevated total arsenic concentrations in porewaters in June compared to April were accompanied by elevated concentrations of total iron, lower concentrations of sulfate and the presence of ammonium and phosphate. The low proportion of methanol-water extractable total arsenic suggests a generally low mobility of arsenic in fen soils. The release of arsenic from solid to solution phases in fen is dominantly controlled by dissolution of iron oxides, redox transformation, and methylation of arsenic, driven by microbial activity in the growing season. As a result, increased concentrations of total arsenic and potentially toxic arsenic species in fen

  2. Complex microbiota of a Chinese "Fen" liquor fermentation starter (Fen-Daqu), revealed by culture-dependent and culture-independent methods

    Zheng, X.; Zheng, Y.; Han, B.; Zwietering, M.H.; Samson, R.A.; Boekhout, T.; Nout, M.J.R.

    2012-01-01

    Daqu is a traditional fermentation starter that is used for Chinese liquor production. Although partly mechanized, its manufacturing process has remained traditional. We investigated the microbial diversity of Fen-Daqu, a starter for light-flavour liquor, using combined culture-dependent and culture

  3. Complex microbiota of a Chinese "Fen" liquor fermentation starter (Fen-Daqu), revealed by culture-dependent and culture-independent methods

    Zheng, X.W.; Yan, Z.; Han, B.Z.; Zwietering, M.H.; Samson, R.A.; Boekhout, T.; Nout, M.J.R.

    2012-01-01

    Daqu is a traditional fermentation starter that is used for Chinese liquor production. Although partly mechanized, its manufacturing process has remained traditional. We investigated the microbial diversity of Fen- Daqu, a starter for light-flavour liquor, using combined culture-dependent and cultur

  4. Effect of peat quality on microbial greenhouse gas formation in an acidic fen

    M. Reiche

    2009-09-01

    Full Text Available Peatlands play an important role in the global carbon cycle and represent both an important stock of soil carbon and a substantial natural source of relevant greenhouse gases like CO2 and CH4. While it is known that the microbial availability of organic matter affects degradation and mineralization processes in peatlands, the manner in which peat organic matter affects the formation of CO2 and CH4 remains unclear. In this study we developed a fast and simple peat quality index in order to estimate its greenhouse gas potential by linking the thermo-degradability of peat with anaerobic CO2 and CH4 formation rates. Peat samples were obtained at several depths (0–40 cm at four sampling locations from an acidic fen (pH∼4.7. CO2 and CH4 formation rates were highly spatially variable and depended on depth, sampling location, and the composition of pyrolysable organic matter. Peat samples active in CO2 and CH4 formation had a quality index above 1.35, and the fraction of thermally labile pyrolyzable organic matter (comparable to easily available carbon substrates for microbial activity obtained by thermogravimetry was above 35%. Curie-point pyrolysis-gas chromatography/mass spectrometry mainly identified carbohydrates and lignin as pyrolysis products in these samples, indicating that undecomposed organic matter was found in this fraction. In contrast, lipids and unspecific pyrolysis products, which indicate recalcitrant and highly decomposed organic matter, correlated significantly with lower CO2 formation and reduced methanogenesis. Our results suggest that undecomposed organic matter is a prerequisite for CH4 and CO2 development in acidic fens. Furthermore, the new peat quality index should aide the estimation of greenhouse gas formation potential resulting from peatland restoration and permafrost thawing

  5. Ácidos fenólicos como antioxidantes Phenolic acids as antioxidants

    SOARES Sergio Eduardo

    2002-01-01

    Os compostos fenólicos têm sido muito estudados devido a sua influência na qualidade dos alimentos. Englobam uma gama enorme de substâncias, entre elas os ácidos fenólicos, os quais, por sua constituição química, possuem propriedades antioxidantes. Assim, a presente revisão procura reunir diversos estudos que avaliaram o potencial antioxidante dos ácidos fenólicos na conservação de alimentos lipídicos. Além disso, são reunidos também estudos sobre a ação antioxidante destes compostos no siste...

  6. Drying-Rewetting and Flooding Impact Denitrifier Activity Rather than Community Structure in a Moderately Acidic Fen

    Palmer, Katharina; Köpp, Julia; Gebauer, Gerhard; Horn, Marcus A.

    2016-01-01

    Wetlands represent sources or sinks of the greenhouse gas nitrous oxide (N2O). The acidic fen Schlöppnerbrunnen emits denitrification derived N2O and is also capable of N2O consumption. Global warming is predicted to cause more extreme weather events in future years, including prolonged drought periods as well as heavy rainfall events, which may result in flooding. Thus, the effects of prolonged drought and flooding events on the abundance, community composition, and activity of fen denitrifiers were investigated in manipulation experiments. The water table in the fen was experimentally lowered for 8 weeks in 2008 and raised for 5.5 months in 2009 on three treatment plots, while three plots were left untreated and served as controls. In situ N2O fluxes were rather unaffected by the drought treatment and were marginally increased by the flooding treatment. Samples were taken before and after treatment in both years. The structural gene markers narG and nosZ were used to assess possible changes in the nitrate reducer and denitrifier community in response to water table manipulations. Detected copy numbers of narG and nosZ were essentially unaffected by the experimental drought and flooding. Terminal restriction fragment length polymorphism (TRFLP) patterns of narG and nosZ were similar before and after experimental drought or experimental flooding, indicating a stable nitrate reducer and denitrifier community in the fen. However, certain TRFs of narG and nosZ transcripts responded to experimental drought or flooding. Nitrate-dependent Michaelis-Menten kinetics were assessed in anoxic microcosms with peat samples taken before and 6 months after the onset of experimental flooding. Maximal reaction velocities vmax were higher after than before flooding in samples from treament but not in those from control plots taken at the same time. The ratio of N2O to N2O + N2 was lower in soil from treatment plots after flooding than in soil from control plots, suggesting

  7. 结构特异性核酸酶FEN1对HBV复制的影响%Effect of structure-specific nucleic acid enzyme FEN1 on HBV replication

    潘万龙; 方岩; 许舸; 单雪峰; 徐蕾; 陈可; 黄爱龙; 胡接力

    2012-01-01

    Objective To lay the foundation for working out new clinical treatment strategies by studying the effect of host factor FEN1 on HBV replication. Methods FEN1 overexpression lentiviral plasmid was constructed with its sequence identified by restriction enzyme digestion and transfected into 293 FT cells. FEN1 protein expression was detected by Western blotting. The plasmid was transfected into stable cell lines with HBV replication. The plasmid pLenti6/V5-D-TOPO was modified by lentivirus packaging and non-transfected plasmid cells served as controls. HBsAg in medium supernatant was detected by ELISA. HBV DNA was detected by RT-PCR and Southern blotting, respectively. Results The plasmid extracted from positive clones was digested by restriction endonuclease, and a bright band was observed in FEN1 and linear plasmid, respectively. The lentiviral plasmid sequencing showed that the sequence was inserted correctly. Western blot analysis displayed that the FEN1 protein expression level was 2-3 fold higher in transfected plasmid cells than in non-transfected plasmid cells. FENl-overexpressed plasmid could transfect stable cell lines with HBV replication. ELISA demonstrated positive HBsAg in medium supernatant with a D450 value of 1.982 ±0.032. RT-PCR revealed intracellular viral DNA with an absolutely-quantified copy number of 1. 18 × 109 . Southern blot analysis indicated that the HBV replication level was significantly up-regulated. Conclusion Structure-specific nuclease FEN1 can significantly promote HBV DNA replication and is thus one of the important regulatory factors for virus replication.%目的 探索宿主因子FEN1对HBV复制过程的影响.方法 构建FEN1过表达慢病毒质粒,酶切鉴定并测序,转染293FT细胞,Western blot检测FEN1蛋白表达.将该质粒转染HBV复制稳定细胞系,设立慢病毒包装改造质粒pLenti6/V5-D-TOPO和不转染质粒的细胞作为对照.ELISA检测细胞上清,Southern blot及Real-time PCR检测HBV DNA

  8. Composition of phenolic acids content in apple (Malus sp pomace / Composição do conteúdo de ácidos fenólicos no bagaço de maçã (Malus sp

    Roseane Fett

    2008-08-01

    Full Text Available The present work aimed the study of phenolic acids composition in apple pomace of Gala and Fuji cultivars. Phenolic acids were fractionated in phenolic acids, esterified and insoluble and analyzed by gas chromatography–mass spectrometry (GC-MS. Sixteen phenolic acids were identified in apple pomace samples. Total phenolic acids in apple pomace from Gala and Fuji cultivars were, in dry weight, 93.94 mg/ g and 68.38 mg/g, respectively. Content of free phenolic acids in apple pomace from Gala cultivar was 29.11 mg/g and the following acids were identified: salicylic, protocatequinic, quinic, p-coumaric, gallic, propylgallate and synapic. Content of free phenolic acids in apple pomace from Fuji cultivar was 16.03 mg/g and the following acids were identified: salicylic, protocatequinic, gallic, ferulic and sinapic. Salicylic was the predominant free phenolic acids found in both cultivars, consisting of 91.67% and 63.57% of the free phenolic acids in Gala and Fuji cultivars, respectively. Chlorogenic acid (1.147 mg/g was found only in apple pomace from Fuji cultivar. Content of esterified phenolic acids in apple pomace from Gala and Fuji cultivars were 53.75 mg/g and 48.29 mg/g, respectively. It was verified that the predominant esterified phenolic acid in pomace from apple Gala is derived from salicylic acid (52.76 mg/g. Acids derived from gallic acid (0.175 mg/g, propylgallate acid (0.198 mg/g, ferulic acid (0.159 mg/g and sinapic acid (0.140 mg/g were also found in Gala cultivar. Regarding to pomace from cultivar Fuji, the main esterified phenolic acid found is also derived from salicylic acid (47.42 mg/g followed by gallic acid (0.270 mg/g, benzoic acid (0.194 mg/g and sinapic acid (0.115 mg/g. Content of insoluble phenolic acids in apple pomace from Gala and Fugi cultivars were, in dry weight, 11.08 mg/g and 4.05 mg/g, respectively. Insoluble phenolic acids derived from salicylic acid were found in higher concentrations in apple pomace from

  9. A 12-year record reveals pre-growing season temperature and water table level threshold effects on the net carbon dioxide exchange in a boreal fen

    This study uses a 12-year time series (2001–2012) of eddy covariance measurements to investigate the long-term net ecosystem exchange (NEE) of carbon dioxide (CO2) and inter-annual variations in relation to abiotic drivers in a boreal fen in northern Sweden. The peatland was a sink for atmospheric CO2 in each of the twelve study years with a 12-year average (± standard deviation) NEE of −58 ± 21 g C m−2 yr−1. For ten out of twelve years, the cumulative annual NEE was within a range of −42 to −79 g C m−2 yr−1 suggesting a general state of resilience of NEE to moderate inter-annual climate variations. However, the annual NEE of −18 and −106 g C m−2 yr−1 in 2006 and 2008, respectively, diverged considerably from this common range. The lower annual CO2 uptake in 2006 was mainly due to late summer emissions related to an exceptional drop in water table level (WTL). A positive relationship (R 2 = 0.65) between pre-growing season (January to April) air temperature (Ta) and summer (June to July) gross ecosystem production (GEP) was observed. We suggest that enhanced GEP due to mild pre-growing season air temperature in combination with air temperature constraints on ecosystem respiration (ER) during the following cooler summer explained most of the greater net CO2 uptake in 2008. Differences in the annual and growing season means of other abiotic variables (e.g. radiation, vapor pressure deficit, precipitation) and growing season properties (i.e. start date, end date, length) were unable to explain the inter-annual variations of NEE. Overall, our findings suggest that this boreal fen acts as a persistent contemporary sink for atmospheric CO2 that is, however, susceptible to severe anomalies in WTL and pre-growing season air temperature associated with predicted changes in climate patterns for the boreal region. (papers)

  10. Método para a Determinação de Ácidos Fenólicos na Parede Celular de Forragens Method for Phenolic Acid Determination in Forage Cell Wall

    Francisco Carlos Deschamps

    2002-07-01

    Full Text Available Há fatores que limitam a digestão das forragens tropicais e estão associados à dinâmica dos ácidos fenólicos da parede celular. Os estudos destes compostos em forragens podem ser facilitados pela disponibilidade de métodos sensíveis que permitam o processamento de grande número de amostras. No presente trabalho, descreve-se um método para a determinação de ácidos fenólicos na parede celular de forragens, utilizando cromatografia líquida de alta eficiência (CLAE. Bagaço de cana, capim-elefante e folhas de mandioca foram utilizados como amostras experimentais. Para remover substâncias solúveis de baixa massa molecular, foram testados etanol 80% e o detergente neutro, determinando seus efeitos sobre a recuperação das moléculas e benefícios no perfil cromatográfico. Para a obtenção dos ácidos fenólicos livres, as amostras foram solubilizadas em NaOH 1 mol/L, 20ºC por 24 horas. O método proposto foi adequado para a determinação de ácidos fenólicos, apresentando grande sensibilidade e produtividade no laboratório. Para minimizar os efeitos negativos da formação de sal resultante da neutralização ácida do extrato alcalino, sugere-se a diluição da amostra ou a injeção de pequeno volume (5 uL no aparelho. O efeito da utilização de solventes como etanol 80% ou detergente neutro é distinto sobre as amostras das gramíneas e leguminosas. A quantidade de extrativos nas folhas de mandioca foi superior a do bagaço de cana e capim-elefante. A concentração de ácidos fenólicos foi pouco alterada pela ação dos solventes, sendo maior nas amostras de bagaço de cana e capim-elefante, em relação às folhas de mandioca. O método apresentado constitui-se em uma importante ferramenta para o estudo dos ácidos fenólicos na parede celular de forragens tropicais.Factors that limit the digestion of tropical forages are associated to the dynamic of cell wall phenolic acids. The study of these compounds in forages may

  11. Calcareous Fens - Source Feature Points

    Minnesota Department of Natural Resources — Pursuant to the provisions of Minnesota Statutes, section 103G.223, this database contains points that represent calcareous fens as defined in Minnesota Rules, part...

  12. Lowland Bogs, Fens and Reedswamps

    Bracken, Fintan; Smiddy, Patrick

    2012-01-01

    This chapter reviews the current and historical studies of the bird communities of lowland bogs, fens and reedswamps in Ireland. The habitat types and bird communities described include raised bogs, cutover and cutaway peatlands and reedswamps.

  13. Remotely sensed hydrological isolation : A key factor predicting plant species distribution in fens

    Sanders, M.E.

    1999-01-01

    In fens the species composition, vegetation structure and succession rate are determined by vegetation management and water chemistry, particularly by the base status and nutrient status. Base-rich and nutrient-rich surface water causes fens to become eutrophied, which leads to an increased biomass production. When part of fens becomes isolated from this surface water (hydrological isolation), it acidifies due to acidic and oligotrophic rainwater dominance. One consequence of decreasing water...

  14. Hydrological landscape settings of base-rich fen mires and fen meadows: an overview

    Grootjans, A.P.; Adema, E.B.; Bleuten, W.; Joosten, H.; Madaras, M.; Janáková, M.; Middleton, B

    2006-01-01

    Question: Why do similar fen meadow communities occur in different landscapes? How does the hydrological system sustain base-rich fen mires and fen meadows? Location: Interdunal wetlands and heathland pools in The Netherlands, percolation mires in Germany, Poland, and Siberia, and calcareous spring fens in the High Tatra, Slovakia. Methods: This review presents an overview of the hydrological conditions of fen mires and fen meadows that are highly valued in nature conservation due to their hi...

  15. Actividad antioxidante de los compuestos fenólicos

    Maestro Durán, R.

    1993-04-01

    Full Text Available This review deals with the oxidation processes induced by light and atmospheric oxygen, as well as the protective action on antioxidant compounds. The available data on the synthetic antioxidants and the problems associated to their use, together with the presence of natural phenolic antioxidants in plants, have been revised. These phenolic antioxidants have been classified in families: phenolic alcohols and acids, cinnamic acids, coumarins, favonoids (flavones and isoflavones, flavonols, flavanones and other phenolic compounds.

    Este trabajo recoge los estudios sobre los mecanismos de oxidación producida por la luz y el oxígeno del aire y sobre la protección de los compuestos antioxidantes contra esta oxidación. Se han revisado los datos existentes sobre los inconvenientes de los antioxidantes sintéticos, que aconsejan sustituirlos por otros naturales y sobre la presencia de antioxidantes naturales de carácter fenólico en las plantas. Los antioxidantes fenólicos se han agrupado por familias: alcoholes y ácidos fenólicos, ácidos cinámicos, cumarinas, flavonoides (flavonas e isoflavonas, flavonoles, flavanonas y otros compuestos fenólicos.

  16. Extração, análise e distribuição dos ácidos fenólicos em genótipos pigmentados e não pigmentados de arroz (Oryza sativa L. Extraction, analysis and distribution of phenolic acids in pigmented and non-pigmented genotypes of rice (Oryza sativa L.

    Nádia Valéria Mussi de Mira

    2008-12-01

    Full Text Available Neste estudo, avaliaram-se a distribuição dos Compostos Fenólicos Totais (CFT e o perfil de ácidos fenólicos, presentes nas frações, solúvel e insolúvel de dez genótipos de arroz (Oryza sativa L. de pericarpo pigmentado e não pigmentado. Devido à sua elevada capacidade antioxidante, os compostos fenólicos vem sendo apontados como possíveis promotores da saúde. Grande parte corresponde aos ácidos fenólicos presentes no grão sob a forma solúvel (livre e conjugada e insolúvel (ligada. Na literatura há poucas informações sobre a contribuição dos compostos fenólicos ligados, cujos teores são costumeiramente subestimados. Os CFT foram quantificados pelo método de Folin-Ciocalteau, enquanto os ácidos fenólicos por RP-HPLC. Na fração solúvel dos genótipos pigmentados, os teores de CFT foram variáveis, mas, em média, 5,7 vezes maiores do que nos não pigmentados (média de 3468 e 602 µg eq. Ácido Ferúlico (AF/g arroz, respectivamente, principalmente devido à presença de antocianinas e proantocianidinas. Na fração insolúvel, os pigmentados apresentaram duas vezes mais CFT do que os não pigmentados (825 e 378 µg eq. AF/g arroz, respectivamente, provavelmente devido à retenção de antocianinas e proantocianidinas, mesmo após cinco extrações consecutivas. Dentre os ácidos fenólicos, o ácido ferúlico foi o principal componente em todos os genótipos estudados, exceto no arroz preto, no qual predominou o ácido protocatecóico.This study was conducted to evaluate the distribution of total phenolic compounds and phenolic acids in the soluble and insoluble fractions of 10 rice (Oryza sativa L. genotypes with pigmented or non-pigmented pericarp. These compounds were reported to exert beneficial effects on human health due to their high antioxidant activities. The total phenolic compounds (CFT in both fractions was determined by the Folin-Ciocalteau method and phenolic acids RP-HPLC with Diode-Array Detection

  17. Caracterização da conversão metabólica de ácidos fenólicos em fenóis voláteis por Brettanomyces/Dekkera = Characterization of the metabolic conversion of phenolic acids to volatile phenols by Brettanomyces/Dekkera

    Gomes, Joana Lousada

    2012-01-01

    A acumulação de fenóis voláteis em vinhos tem causado grande preocupação na enologia moderna, sendo considerado, nos dias de hoje, um ponto-chave no controlo da qualidade dos vinhos. Os vinilfenóis (4-vinilfenol e 4-vinilguaiacol) e etilfenóis (4- etilfenol e 4-etilguaiacol) podem ser produzidos nos vinhos na sequência de atividade microbiana dando origem a odores e sabores indesejados geralmente descritos como “couro”, “suor de cavalo”, “animal” e “medicinal”. A origem exata d...

  18. Actividad antioxidante, compuestos fenólicos y ácido ascórbico de frutillas en dos sistemas de producción Antioxidant activity, phenolic compounds and ascorbic acid content in strawberries from two crop production systems

    Rufino Fernando F Cantillano

    2012-12-01

    Full Text Available El objetivo de este trabajo fue determinar la influencia del sistema de producción y del período de almacenamiento de frutillas sobre la pérdida de masa, compuestos fenólicos totales, antocianinas totales, ácido ascórbico (vitamina C, actividad antioxidante y sus correlaciones. En este experimento fueron utilizadas frutillas 'Camarosa' y 'Camino Real' con madurez comercial, procedentes de cultivos en sistemas de producción orgánico y convencional, localizados en el municipio de Pelotas-RS. Los frutos fueron almacenados durante 0, 2, 5 y 8 días a 1ºC y 90-95% de HR. En general, el contenido de fenoles totales, de antocianinas totales y la actividad antioxidante aumentaron durante el almacenamiento refrigerado, mientras que los contenidos de ácido ascórbico y de masa fresca disminuyeron significativamente. Los contenidos de fenoles totales y de antocianinas totales presentaron correlación positiva con la actividad antioxidante, siendo la correlación con el contenido de ácido ascórbico negativa. Las frutillas producidas en sistema orgánico y conservadas durante cinco días, mostraron mayores valores de actividad antioxidante. Después de ocho días de almacenamiento a 1ºC, los frutos del sistema de producción orgánico presentaron menor degradación de antocianinas y de ácido ascórbico que los frutos del sistema de producción convencional.The aim of this study was to determine the influence of the crop production system and storage period on weight loss, total phenolic content, total anthocyanin content, ascorbic acid (vitamin C content, and antioxidant activity in strawberries, as well as their correlations. For this experiment, strawberry fruits of 'Camarosa' and 'Camino Real' at commercial maturity from both organic and conventional crop production systems located in Pelotas, Brazil, were used. The fruits were cold stored for 0, 2, 5, and 8 days at 1ºC and 90-95% RH. In general the total phenolic, total anthocyanin levels

  19. Avaliação da atividade antioxidante e identificação dos ácidos fenólicos presentes no bagaço de maçã cv. Gala Evaluation of antioxidant activity and identification of phenolic acids present in the pomace of Gala variety apples

    Marcia Soares

    2008-09-01

    Full Text Available No processamento da maçã para obtenção do suco, ocorre a formação de uma elevada quantidade de resíduo, representado pelas cascas e sementes, no qual são encontradas diversas substâncias, como os compostos fenólicos, aos quais são atribuídas as propriedades antioxidantes. Este estudo teve como objetivo avaliar o conteúdo de compostos fenólicos totais e a atividade antioxidante in vitro de extratos e frações de ácidos fenólicos livres, esterificadas solúveis e esterificadas insolúveis, obtidos por diferentes solventes, a partir do resíduo da maçã cv. Gala pelos métodos DPPH (2,2-difenil-1-picrilhidrazilo e ABTS [2,2'-azino-bis (3-etilbenzotiazolin 6-ácido sulfônico], além da identificação dos ácidos fenólicos por cromatografia gasosa. O sistema acetona 75% (v/v em água foi mais eficaz na extração dos compostos fenólicos totais. A atividade antioxidante neste extrato foi 4,83 e 25,46 µmol TEAC.g-1 de amostra com o método ABTS e de 7,43 e 39,15 µmol TEAC.g-1 pelo método DPPH, expressos em base úmida e seca, respectivamente. O teor de flavanóis foi 11,05 e 58,20 mg.100 g-1 em base úmida e seca, respectivamente. Houve uma correlação positiva entre o conteúdo de fenólicos totais e atividade antioxidante (r² = 0,9283. Foram identificados os ácidos fenólicos salícilico, gálico, propilgalato e sináptico nas três frações avaliadas, o primeiro estando presente em maior concentração em todas as frações estudadas. Os resultados indicam o potencial antioxidante do bagaço de maçã.Apple processing to obtain juice produces a great amount of discarded material constituted by peel and seed. Several substances, including phenolic compounds, to which antioxidant activity is attributed, are found in these fractions. This work aimed at evaluating total phenolic compounds and in vitro antioxidant activity of extracts and phenolic fractions (free, soluble esterified and insoluble esterified of apple, cv. Gala

  20. Método para a Determinação de Ácidos Fenólicos na Parede Celular de Forragens Method for Phenolic Acid Determination in Forage Cell Wall

    Francisco Carlos Deschamps; Luiz Pereira Ramos

    2002-01-01

    Há fatores que limitam a digestão das forragens tropicais e estão associados à dinâmica dos ácidos fenólicos da parede celular. Os estudos destes compostos em forragens podem ser facilitados pela disponibilidade de métodos sensíveis que permitam o processamento de grande número de amostras. No presente trabalho, descreve-se um método para a determinação de ácidos fenólicos na parede celular de forragens, utilizando cromatografia líquida de alta eficiência (CLAE). Bagaço de cana, capim-elefant...

  1. Polyploid genome of Camelina sativa revealed by isolation of fatty acid synthesis genes

    Shewmaker Christine K; Goldstein Elianna; Schroeder Jesara; Comai Luca; Beilstein Mark; Ditt Renata F; Hutcheon Carolyn; Nguyen Van Thu; De Rocher Jay; Kiser Jack

    2010-01-01

    Abstract Background Camelina sativa, an oilseed crop in the Brassicaceae family, has inspired renewed interest due to its potential for biofuels applications. Little is understood of the nature of the C. sativa genome, however. A study was undertaken to characterize two genes in the fatty acid biosynthesis pathway, fatty acid desaturase (FAD) 2 and fatty acid elongase (FAE) 1, which revealed unexpected complexity in the C. sativa genome. Results In C. sativa, Southern analysis indicates the p...

  2. Effect of Groundwater Abstraction on Fen Ecosystems

    Johansen, Ole; Pedersen, Morten Lauge; Jensen, Jacob Birk

    2011-01-01

    Quantifying the effects of groundwater abstraction on fen ecosystems located in discharge areas can be complicated. The water level in fens is close to the terrain surface most of the year and it is controlled by a relatively constant groundwater exfiltration. It is difficult to measure...... the exfiltration fluxes and thus water level data is typically used to evaluate if the ecosystem is affected. The paper presents collected data and analysis from a case study, where the hydrological effect of groundwater abstraction on rich fens and springs in a Danish river valley has been studied. The natural...... within a distance of 1.5 km to a planned well field. In the river valley the interaction between groundwater and surface water is strongly affected by low permeable sediments. These sediments reduce the direct discharge to the river and have a large impact on the functioning and presence of the rich fen...

  3. Actividad antioxidante, compuestos fenólicos y ácido ascórbico de frutillas en dos sistemas de producción Antioxidant activity, phenolic compounds and ascorbic acid content in strawberries from two crop production systems

    Rufino Fernando F Cantillano; Julia Maria M Ávila; Maria do Carmo R Peralba; Tânia Mara Pizzolato; Ricardo P Toralles

    2012-01-01

    El objetivo de este trabajo fue determinar la influencia del sistema de producción y del período de almacenamiento de frutillas sobre la pérdida de masa, compuestos fenólicos totales, antocianinas totales, ácido ascórbico (vitamina C), actividad antioxidante y sus correlaciones. En este experimento fueron utilizadas frutillas 'Camarosa' y 'Camino Real' con madurez comercial, procedentes de cultivos en sistemas de producción orgánico y convencional, localizados en el municipio de Pelotas-RS. L...

  4. Modelling hydrological management for the restoration of acidified floating fens

    Dekker, Stefan C.; Barendregt, Aat; Bootsma, Margien C.; Schot, Paul P.

    2005-12-01

    Wetlands show a large decline in biodiversity. To protect and restore this biodiversity, many restoration projects are carried out. Hydrology in wetlands controls the chemical and biological processes and may be the most important factor regulating wetland function and development. Hydrological models may be used to simulate these processes and to evaluate management scenarios for restoration. HYDRUS2D, a combined saturated-unsaturated groundwater flow and transport model, is presented. This simulates near-surface hydrological processes in an acidified floating fen, with the aim to evaluate the effect of hydrological restoration in terms of conditions for biodiversity. In the acidified floating fen in the nature reserve Ilperveld (The Netherlands), a trench system was dug for the purpose of creating a runoff channel for acid rainwater in wet periods and to enable circum-neutral surface water to enter the fen in dry periods. The model is calibrated against measured conductivity values for a 5 year period. From the model simulations, it was found that lateral flow in the floating raft is limited. Furthermore, the model shows that the best management option is a combination of trenches and inundation, which gave the best soil water quality in the root zone. It is concluded that hydrological models can be used for the calculation of management scenarios in restoration projects. The combined saturated-unsaturated model concept used in this paper is able to incorporate the governing hydrological processes in the wetland root zones. Copyright

  5. Disruption of retinoic acid receptor alpha reveals the growth promoter face of retinoic acid.

    Giulia Somenzi

    Full Text Available BACKGROUND: Retinoic acid (RA, the bioactive derivative of Vitamin A, by epigenetically controlling transcription through the RA-receptors (RARs, exerts a potent antiproliferative effect on human cells. However, a number of studies show that RA can also promote cell survival and growth. In the course of one of our studies we observed that disruption of RA-receptor alpha, RARalpha, abrogates the RA-mediated growth-inhibitory effects and unmasks the growth-promoting face of RA (Ren et al., Mol. Cell. Biol., 2005, 25:10591. The objective of this study was to investigate whether RA can differentially govern cell growth, in the presence and absence of RARalpha, through differential regulation of the "rheostat" comprising ceramide (CER, the sphingolipid with growth-inhibitory activity, and sphingosine-1-phosphate (S1P, the sphingolipid with prosurvival activity. METHODOLOGY/PRINCIPAL FINDINGS: We found that functional inhibition of endogenous RARalpha in breast cancer cells by using either RARalpha specific antagonists or a dominant negative RARalpha mutant hampers on one hand the RA-induced upregulation of neutral sphingomyelinase (nSMase-mediated CER synthesis, and on the other hand the RA-induced downregulation of sphingosine kinase 1, SK1, pivotal for S1P synthesis. In association with RA inability to regulate the sphingolipid rheostat, cells not only survive, but also grow more in response to RA both in vitro and in vivo. By combining genetic, pharmacological and biochemical approaches, we mechanistically demonstrated that RA-induced growth is, at least in part, due to non-RAR-mediated activation of the SK1-S1P signaling. CONCLUSIONS/SIGNIFICANCE: In the presence of functional RARalpha, RA inhibits cell growth by concertedly, and inversely, modulating the CER and S1P synthetic pathways. In the absence of a functional RARalpha, RA-in a non-RAR-mediated fashion-promotes cell growth by activating the prosurvival S1P signaling. These two distinct

  6. Conservation and Biodiversity of Rich Fens

    Andersen, Dagmar Kappel

    2014-01-01

    Rich fen is a habitat type dependent on a constant supply of nutrient poor, calcium rich groundwater. A high, stable groundwater table, relatively high pH combined with nutrient poor conditions support a special and very species rich vegetation including many rare and threatened plant species. In...

  7. Elastoviscous Transitions of Articular Cartilage Reveal a Mechanism of Synergy between Lubricin and Hyaluronic Acid

    Bonnevie, Edward D.; Galesso, Devis; Secchieri, Cynthia; Cohen, Itai; Bonassar, Lawrence J.

    2015-01-01

    When lubricated by synovial fluid, articular cartilage provides some of the lowest friction coefficients found in nature. While it is known that macromolecular constituents of synovial fluid provide it with its lubricating ability, it is not fully understood how two of the main molecules, lubricin and hyaluronic acid, lubricate and interact with one another. Here, we develop a novel framework for cartilage lubrication based on the elastoviscous transition to show that lubricin and hyaluronic acid lubricate by distinct mechanisms. Such analysis revealed nonspecific interactions between these molecules in which lubricin acts to concentrate hyaluronic acid near the tissue surface and promotes a transition to a low friction regime consistent with the theory of viscous boundary lubrication. Understanding the mechanics of synovial fluid not only provides insight into the progression of diseases such as arthritis, but also may be applicable to the development of new biomimetic lubricants. PMID:26599797

  8. Water stress responses of tomato mutants impaired in hormone biosynthesis reveal abscisic acid, jasmonic acid and salicylic acid interactions

    Valeria eMuñoz

    2015-11-01

    Full Text Available To investigate the putative crosstalk between JA and ABA in Solanum lycopersicum plants in response to drought, suppressor of prosystemin-mediated responses2 (spr2, JA-deficient and flacca (flc, ABA-deficient mutants together with the naphthalene/salicylate hydroxylase (NahG transgenic (SA-deficient line were used. Hormone profiling and gene expression of key enzymes in ABA, JA and SA biosynthesis were analyzed during early stages of drought. ABA accumulation was comparable in spr2 and wild type (WT plants whereas expression of 9-cis-epoxycarotenoid dioxygenase 1 (NCED1 and NCED2 was different, implying a compensation mechanism between NCED genes and an organ-specific regulation of NCED1 expression. JA levels and 12-oxo-phytodienoic acid reductase 3 (OPR3 expression in flc plants suggest that ABA regulates the induction of the OPR3 gene in roots. By contrast, ABA treatment to flc plants leads to a reduction of JA and SA contents. Furthermore, different pattern of SA accumulation (and expression of isochorismate synthase and phenylalanine ammonia lyase 1 was observed between WT seedlings and mutants, suggesting that SA plays an important role on the early response of tomato plants to drought and also that JA and ABA modulate its biosynthesis. Finally, hormone profiling in spr2 and NahG plants indicate a crosstalk between JA and SA that could enhance tolerance of tomato to water stress.

  9. Water Stress Responses of Tomato Mutants Impaired in Hormone Biosynthesis Reveal Abscisic Acid, Jasmonic Acid and Salicylic Acid Interactions.

    Muñoz-Espinoza, Valeria A; López-Climent, María F; Casaretto, José A; Gómez-Cadenas, Aurelio

    2015-01-01

    To investigate the putative crosstalk between JA and ABA in Solanum lycopersicum plants in response to drought, suppressor of prosystemin-mediated responses2 (spr2, JA-deficient) and flacca (flc, ABA-deficient) mutants together with the naphthalene/salicylate hydroxylase (NahG) transgenic (SA-deficient) line were used. Hormone profiling and gene expression of key enzymes in ABA, JA and SA biosynthesis were analyzed during early stages of drought. ABA accumulation was comparable in spr2 and wild type (WT) plants whereas expression of 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and NCED2 was different, implying a compensation mechanism between NCED genes and an organ-specific regulation of NCED1 expression. JA levels and 12-oxo-phytodienoic acid reductase 3 (OPR3) expression in flc plants suggest that ABA regulates the induction of the OPR3 gene in roots. By contrast, ABA treatment to flc plants leads to a reduction of JA and SA contents. Furthermore, different pattern of SA accumulation (and expression of isochorismate synthase and phenylalanine ammonia lyase 1) was observed between WT seedlings and mutants, suggesting that SA plays an important role on the early response of tomato plants to drought and also that JA and ABA modulate its biosynthesis. Finally, hormone profiling in spr2 and NahG plants indicate a crosstalk between JA and SA that could enhance tolerance of tomato to water stress. PMID:26635826

  10. Land cover or climate? In search of dominant factors inducing groundwater recharge and fen hydrology in European scale

    Grygoruk, Mateusz; Kotowski, Wiktor

    2016-04-01

    Groundwater recharge plays the crucial role in development and stability of fens. It was hypothesized that the mid- and late-Holocene acceleration of fens' development in Europe could have been induced by changes in land cover: decreasing areas of forests resulting from the expanding agriculture have enhanced groundwater recharge by decreasing evapotranspiration and interception and promoting infiltration. However, regardless human-related changes of the landscape, recorded climatic fluctuations could also be considered as drivers of changing groundwater recharge that affects fen stability and development. Nowadays, when up to 90% of European wetlands is considered degraded, assessing vulnerability of groundwater recharge to changing landscape and climate is of the crucial importance for setting fen restoration and management strategies. Main goal of our study was to assess the magnitude of changes in groundwater recharge estimation resulting from modelled changes of the landscape and climatic features in >300 fens located in Poland, Germany, The Netherlands, Sweden, UK and Norway. In our approach we (1) delineated the most probable extents of catchments of particular fens analysed, (2) assumed hypothetical and the most probable changes of land cover within these catchments, (3) assumed the most probable ranges of climatic changes in each of the catchments including historical reconstructions (Holocene) and future projections (A1B scenario, CSIRO:MK3 and UKMO:HADCM3 GCM-RCM ensembles), (4) developed, tested and calibrated automatic, GIS-based groundwater recharge calculation algorithm to be applied in the study, (5) calculated groundwater recharge in multiple probable combinations of landscape and climatic conditions and (6) performed statistical analysis in order to reveal whether the climate or landscape changes were the dominant factors that could have probably influenced groundwater recharge in catchments of fens analysed. We revealed that in the case of 80% of

  11. Metabolomic Analyses of Leishmania Reveal Multiple Species Differences and Large Differences in Amino Acid Metabolism.

    Gareth D Westrop

    Full Text Available Comparative genomic analyses of Leishmania species have revealed relatively minor heterogeneity amongst recognised housekeeping genes and yet the species cause distinct infections and pathogenesis in their mammalian hosts. To gain greater information on the biochemical variation between species, and insights into possible metabolic mechanisms underpinning visceral and cutaneous leishmaniasis, we have undertaken in this study a comparative analysis of the metabolomes of promastigotes of L. donovani, L. major and L. mexicana. The analysis revealed 64 metabolites with confirmed identity differing 3-fold or more between the cell extracts of species, with 161 putatively identified metabolites differing similarly. Analysis of the media from cultures revealed an at least 3-fold difference in use or excretion of 43 metabolites of confirmed identity and 87 putatively identified metabolites that differed to a similar extent. Strikingly large differences were detected in their extent of amino acid use and metabolism, especially for tryptophan, aspartate, arginine and proline. Major pathways of tryptophan and arginine catabolism were shown to be to indole-3-lactate and arginic acid, respectively, which were excreted. The data presented provide clear evidence on the value of global metabolomic analyses in detecting species-specific metabolic features, thus application of this technology should be a major contributor to gaining greater understanding of how pathogens are adapted to infecting their hosts.

  12. Novel fen ecosystems in western North Carolina

    Wilcox, J. D.

    2012-12-01

    Western North Carolina is mountainous, and groundwater flows from hillslope recharge zones to valley stream and spring discharge zones. Depending on surface topography and geologic conditions, the water table may approach or intersect the ground surface to form seepage wetlands, or fens. Fen ecosystems can be very sensitive to changes in land use, groundwater pumping, and upslope development. This presentation will focus on two sites where historical land use and human activity played important roles in creating or preserving fen ecosystems. Both sites now support—and are being managed to protect—federally endangered flora and fauna. The first site is home to Sarracenia oreophilia, an endangered pitcher plant that thrives on saturated soils with low nutrient content. The site's early history includes tree clearing, drain tile installation, and cattle grazing, while more recent management activities have included drain tile excavation, manual invasive removal, and prescribed burns. A 15-year water-level record indicates seasonal artesian conditions wet a 3m clay unit (K=2E-5 cm/sec) beneath the site, which is able to retain moisture during drier periods. Shorter "clay wetting periods" during drought years (1999-2000; 2007-2008) correspond to reduced clump counts in pitcher-plant surveys. The second site is a former aggregate quarry that now supports over 60 bog turtles (Clemmys muhlenbergii). The biggest threat to this site is encroachment of non-native and invasive multiflora rose (Rosa multiflora) and other large woody species. Management activities include manual removal and prescribed goat herbivory. Current efforts to characterize the springs, water-table, and surface-water flows will be used to detect changes in the future to the hydrologic regime in the fen.

  13. Biosorption of Metallic Elements onto Fen Peat

    Krumins, Janis; Robalds, Artis

    2014-12-01

    Industrial development and anthropogenic activity have a huge impact on the environment, forcing society to find new and cost-effective environment treatment technologies. One of the most effective and environmentally friendly methods is the use of biosorbents, for which peat is one of the most cost-effective materials. The adsorption capabilities of peat sediments are well known; however, mainly raised bog peat is used for environmental treatment, and thus the abilities of fen peat are underestimated. The aim of this research was to assess the fen peat suitability as an adsorbent for metallic elements. In this study we have determined the sorption characteristics of Ca, Mg, K, Na, Cu and Pb and results show that fen peat deposits have a huge variability as a biosorbent due to their variable botanical composition and complex properties, for instance, under equal conditions, wood-sedge peat can have higher lead adsorption capacity than wood peat. However, due to its natural content of metallic elements, the sorption capacity overall is lower than it is for raised bog peat, although the high pH reaction encourage a high mobility metals.

  14. Arabidopsis thaliana auxotrophs reveal a tryptophan-independent biosynthetic pathway for indole-3-acetic acid.

    Normanly, J; Cohen, J D; Fink, G. R.

    1993-01-01

    We used tryptophan auxotrophs of the dicot Arabidopsis thaliana (wall cress) to determine whether tryptophan has the capacity to serve as a precursor to the auxin, indole-3-acetic acid (IAA). Quantitative gas chromatography-selected ion monitoring-mass spectrometry (GC-SIM-MS) revealed that the trp2-1 mutant, which is defective in the conversion of indole to tryptophan, accumulated amide- and ester-linked IAA at levels 38-fold and 19-fold, respectively, above those of the wild type. Tryptopha...

  15. Efeito do tratamento térmico na concentração de carotenóides, compostos fenólicos, ácido ascórbico e capacidade antioxidante do suco de tangerina murcote Effect of thermal treatment on the carotenoid, phenolic compound and ascorbic acid concentrations, and the antioxidant capacity of murcott tangerine juice

    André de Souza Dutra

    2012-09-01

    Full Text Available Neste estudo, avaliou-se o efeito do tratamento térmico do suco de tangerina murcote em relação ao teor de carotenóides totais, ao perfil de carotenóides (luteína, zeaxantina, β-criptoxantina e β-caroteno, aos compostos fenólicos totais, ao ácido ascórbico e à capacidade antioxidante. No processo, utilizou-se um trocador de calor tubular, sendo avaliados 11 tratamentos seguindo um ensaio fatorial completo 2² com três repetições no ponto central, com quatro pontos axiais e uma região de observação de 88 a 100 ºC e 16 a 44 s. O teor de caratenóides totais decresceu de forma significativa em quase todos os tratamentos aplicados, se comparado ao valor encontrado para o suco in natura. A maioria dos tratamentos não reduziu de forma significativa os teores dos caratenóides luteína, zeaxantina e β-criptoxantina. Além disso, o teor de β-caroteno não sofreu alterações significativas em todos os tratamentos avaliados. A análise de variância mostrou que, para os caratenóides, não ocorreram interações significativas entre as variáveis temperatura e tempo. Os teores de ácido ascórbico e compostos fenólicos totais apresentaram reduções em seis condições avaliadas, ao passo que, em quatro, observou-se um aumento dos teores de compostos fenólicos totais, causado provavelmente pela evaporação da água presente no suco. A maior redução do teor de ácido ascórbico e o maior aumento para compostos fenólicos totais foi observado para o binômio 100 ºC/30 s. O teor de ácido ascórbico sofreu de forma significativa a influência da temperatura e esse processo de degradação pode ser descrito por meio de um modelo quadrático. Todos os tratamentos utilizados reduziram a capacidade antioxidante do suco, sendo mais intensa para o binômio 100 ºC/30 s. As variações observadas não alteraram de maneira considerável as características nutricionais do suco e os tratamentos térmicos realizados a 94 ºC por 16 a 44 s

  16. Water flow and solute transport in floating fen root mats

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    Floating fens are valuable wetlands, found in North-Western Europe, that are formed by floating root mats when old turf ponds are colonized by plants. These terrestrialization ecosystems are known for their biodiversity and the presence of rare plant species, and the root mats reveal different vegetation zones at a small scale. The vegetation zones are a result of strong gradients in abiotic conditions, including groundwater dynamics, nutrients and pH. To prevent irreversible drought effects such as land subsidence and mineralization of peat, water management involves import of water from elsewhere to maintain constant surface water levels. Imported water may have elevated levels of salinity during dry summers, and salt exposure may threaten the vegetation. To assess the risk of exposure of the rare plant species to salinity, the hydrology of such root mats must be understood. Physical properties of root mats have scarcely been investigated. We have measured soil characteristics, hydraulic conductivity, vertical root mat movement and groundwater dynamics in a floating root mat in the nature reserve Nieuwkoopse Plassen, in the Netherlands. The root mat mostly consists of roots and organic material, in which the soil has a high saturated water content, and strongly varies in its stage of decomposition. We have found a distinct negative correlation between degree of decomposition and hydraulic conductivity, similar to observations for bogs in the literature. Our results show that the relatively young, thin edge of the root mat that colonizes the surface water has a high hydraulic conductivity and floats in the surface water, resulting in very small groundwater fluctuations within the root mat. The older part of the root mat, that is connected to the deeper peat layers is hydrologically more isolated and the material has a lower conductivity. Here, the groundwater fluctuates strongly with atmospheric forcing. The zones of hydraulic properties and vegetation, appear to

  17. Polyploid genome of Camelina sativa revealed by isolation of fatty acid synthesis genes

    Shewmaker Christine K

    2010-10-01

    Full Text Available Abstract Background Camelina sativa, an oilseed crop in the Brassicaceae family, has inspired renewed interest due to its potential for biofuels applications. Little is understood of the nature of the C. sativa genome, however. A study was undertaken to characterize two genes in the fatty acid biosynthesis pathway, fatty acid desaturase (FAD 2 and fatty acid elongase (FAE 1, which revealed unexpected complexity in the C. sativa genome. Results In C. sativa, Southern analysis indicates the presence of three copies of both FAD2 and FAE1 as well as LFY, a known single copy gene in other species. All three copies of both CsFAD2 and CsFAE1 are expressed in developing seeds, and sequence alignments show that previously described conserved sites are present, suggesting that all three copies of both genes could be functional. The regions downstream of CsFAD2 and upstream of CsFAE1 demonstrate co-linearity with the Arabidopsis genome. In addition, three expressed haplotypes were observed for six predicted single-copy genes in 454 sequencing analysis and results from flow cytometry indicate that the DNA content of C. sativa is approximately three-fold that of diploid Camelina relatives. Phylogenetic analyses further support a history of duplication and indicate that C. sativa and C. microcarpa might share a parental genome. Conclusions There is compelling evidence for triplication of the C. sativa genome, including a larger chromosome number and three-fold larger measured genome size than other Camelina relatives, three isolated copies of FAD2, FAE1, and the KCS17-FAE1 intergenic region, and three expressed haplotypes observed for six predicted single-copy genes. Based on these results, we propose that C. sativa be considered an allohexaploid. The characterization of fatty acid synthesis pathway genes will allow for the future manipulation of oil composition of this emerging biofuel crop; however, targeted manipulations of oil composition and general

  18. Acidic Properties and Structure-Activity Correlations of Solid Acid Catalysts Revealed by Solid-State NMR Spectroscopy.

    Zheng, Anmin; Li, Shenhui; Liu, Shang-Bin; Deng, Feng

    2016-04-19

    Solid acid materials with tunable structural and acidic properties are promising heterogeneous catalysts for manipulating and/or emulating the activity and selectivity of industrially important catalytic reactions. On the other hand, the performances of acid-catalyzed reactions are mostly dictated by the acidic features, namely, type (Brønsted vs Lewis acidity), amount, strength, and local environment of acid sites. The latter is relevant to their location (intra- vs extracrystalline), and possible confinement and Brønsted-Lewis acid synergy effects that may strongly affect the host-guest interactions, reaction mechanism, and shape selectivity of the catalytic system. This account aims to highlight some important applications of state-of-the-art solid-state NMR (SSNMR) techniques for exploring the structural and acidic properties of solid acid catalysts as well as their catalytic performances and relevant reaction pathway invoked. In addition, density functional theory (DFT) calculations may be exploited in conjunction with experimental SSNMR studies to verify the structure-activity correlations of the catalytic system at a microscopic scale. We describe in this Account the developments and applications of advanced ex situ and/or in situ SSNMR techniques, such as two-dimensional (2D) double-quantum magic-angle spinning (DQ MAS) homonuclear correlation spectroscopy for structural investigation of solid acids as well as study of their acidic properties. Moreover, the energies and electronic structures of the catalysts and detailed catalytic reaction processes, including the identification of reaction species, elucidation of reaction mechanism, and verification of structure-activity correlations, made available by DFT theoretical calculations were also discussed. Relevant discussions will focus primarily on results obtained from our laboratories in the past decade, including (i) quantitative and qualitative acidity characterization utilizing assorted probe molecules

  19. Extração, análise e distribuição dos ácidos fenólicos em genótipos pigmentados e não pigmentados de arroz (Oryza sativa L.) Extraction, analysis and distribution of phenolic acids in pigmented and non-pigmented genotypes of rice (Oryza sativa L.)

    Nádia Valéria Mussi de Mira; Rosa Maria Cerdeira Barros; Moacir Antonio Schiocchet; José Alberto Noldin; Ursula Maria Lanfer-Marquez

    2008-01-01

    Neste estudo, avaliaram-se a distribuição dos Compostos Fenólicos Totais (CFT) e o perfil de ácidos fenólicos, presentes nas frações, solúvel e insolúvel de dez genótipos de arroz (Oryza sativa L.) de pericarpo pigmentado e não pigmentado. Devido à sua elevada capacidade antioxidante, os compostos fenólicos vem sendo apontados como possíveis promotores da saúde. Grande parte corresponde aos ácidos fenólicos presentes no grão sob a forma solúvel (livre e conjugada) e insolúvel (ligada). Na lit...

  20. Interaction between APC and Fen1 during breast carcinogenesis.

    Narayan, Satya; Jaiswal, Aruna S; Law, Brian K; Kamal, Mohammad A; Sharma, Arun K; Hromas, Robert A

    2016-05-01

    Aberrant DNA base excision repair (BER) contributes to malignant transformation. However, inter-individual variations in DNA repair capacity plays a key role in modifying breast cancer risk. We review here emerging evidence that two proteins involved in BER - adenomatous polyposis coli (APC) and flap endonuclease 1 (Fen1) - promote the development of breast cancer through novel mechanisms. APC and Fen1 expression and interaction is increased in breast tumors versus normal cells, APC interacts with and blocks Fen1 activity in Pol-β-directed LP-BER, and abrogation of LP-BER is linked with cigarette smoke condensate-induced transformation of normal breast epithelial cells. Carcinogens increase expression of APC and Fen1 in spontaneously immortalized human breast epithelial cells, human colon cancer cells, and mouse embryonic fibroblasts. Since APC and Fen1 are tumor suppressors, an increase in their levels could protect against carcinogenesis; however, this does not seem to be the case. Elevated Fen1 levels in breast and lung cancer cells may reflect the enhanced proliferation of cancer cells or increased DNA damage in cancer cells compared to normal cells. Inactivation of the tumor suppressor functions of APC and Fen1 is due to their interaction, which may act as a susceptibility factor for breast cancer. The increased interaction of APC and Fen1 may occur due to polypmorphic and/or mutational variation in these genes. Screening of APC and Fen1 polymorphic and/or mutational variations and APC/Fen1 interaction may permit assessment of individual DNA repair capability and the risk for breast cancer development. Such individuals might lower their breast cancer risk by reducing exposure to carcinogens. Stratifying individuals according to susceptibility would greatly assist epidemiologic studies of the impact of suspected environmental carcinogens. Additionally, a mechanistic understanding of the interaction of APC and Fen1 may provide the basis for developing new and

  1. Comparative Transcriptomics Reveals Jasmonic Acid-Associated Metabolism Related to Cotton Fiber Initiation.

    Liman Wang

    Full Text Available Analysis of mutants and gene expression patterns provides a powerful approach for investigating genes involved in key stages of plant fiber development. In this study, lintless-fuzzless XinWX and linted-fuzzless XinFLM with a single genetic locus difference for lint were used to identify differentially expressed genes. Scanning electron microscopy showed fiber initiation in XinFLM at 0 days post anthesis (DPA. Fiber transcriptional profiling of the lines at three initiation developmental stages (-1, 0, 1 DPA was performed using an oligonucleotide microarray. Loop comparisons of the differentially expressed genes within and between the lines was carried out, and functional classification and enrichment analysis showed that gene expression patterns during fiber initiation were heavily associated with hormone metabolism, transcription factor regulation, lipid transport, and asparagine biosynthetic processes, as previously reported. Further, four members of the allene-oxide cyclase (AOC family that function in jasmonate biosynthesis were parallel up-regulation in fiber initiation, especially at -1 DPA, compared to other tissues and organs in linted-fuzzed TM-1. Real time-quantitative PCR (RT-qPCR analysis in different fiber mutant lines revealed that AOCs were up-regulated higher at -1 DPA in lintless-fuzzless than that in linted-fuzzless and linted-fuzzed materials, and transcription of the AOCs was increased under jasmonic acid (JA treatment. Expression analysis of JA biosynthesis-associated genes between XinWX and XinFLM showed that they were up-regulated during fiber initiation in the fuzzless-lintless mutant. Taken together, jasmonic acid-associated metabolism was related to cotton fiber initiation. Parallel up-regulation of AOCs expression may be important for normal fiber initiation development, while overproduction of AOCs might disrupt normal fiber development.

  2. Comparative genomics of lactic acid bacteria reveals a niche-specific gene set

    Callanan Michael

    2009-03-01

    Full Text Available Abstract Background The recently sequenced genome of Lactobacillus helveticus DPC4571 1 revealed a dairy organism with significant homology (75% of genes are homologous to a probiotic bacteria Lb. acidophilus NCFM 2. This led us to hypothesise that a group of genes could be determined which could define an organism's niche. Results Taking 11 fully sequenced lactic acid bacteria (LAB as our target, (3 dairy LAB, 5 gut LAB and 3 multi-niche LAB, we demonstrated that the presence or absence of certain genes involved in sugar metabolism, the proteolytic system, and restriction modification enzymes were pivotal in suggesting the niche of a strain. We identified 9 niche specific genes, of which 6 are dairy specific and 3 are gut specific. The dairy specific genes identified in Lactobacillus helveticus DPC4571 were lhv_1161 and lhv_1171, encoding components of the proteolytic system, lhv_1031 lhv_1152, lhv_1978 and lhv_0028 encoding restriction endonuclease genes, while bile salt hydrolase genes lba_0892 and lba_1078, and the sugar metabolism gene lba_1689 from Lb. acidophilus NCFM were identified as gut specific genes. Conclusion Comparative analysis revealed that if an organism had homologs to the dairy specific geneset, it probably came from a dairy environment, whilst if it had homologs to gut specific genes, it was highly likely to be of intestinal origin. We propose that this "barcode" of 9 genes will be a useful initial guide to researchers in the LAB field to indicate an organism's ability to occupy a specific niche.

  3. Fens as whole-ecosystem gauges of groundwater recharge under climate change

    Drexler, Judith Z.; Knifong, Donna L.; JayLee Tuil; Flint, Lorraine E.; Flint, Alan L.

    2013-01-01

    Currently, little is known about the impact of climate change on groundwater recharge in the Sierra Nevada and southern Cascade Range of California or other mountainous regions of the world. The purpose of this study was to determine whether small alpine peat lands called fens can be used as whole-ecosystem gauges of groundwater recharge through time. Fens are sustained by groundwater discharge and are highly sensitive to changes in groundwater flow due to hydrologic disturbance including climate change. Seven fens in the Sierra Nevada and southern Cascade Range were studied over a 50-80 year period using historic aerial photography. In each aerial photograph, fen areas were identified as open lawn and partially treed areas that exhibited (1) dark brownish-green coloring or various shades of gray and black in black and white imagery and (2) mottling of colors and clustering of vegetation, which signified a distinct moss canopy with overlying clumped sedge vegetation. In addition to the aerial photography study, a climate analysis for the study sites was carried out using both measured data (U.S. Department of Agriculture Natural Resources Conservation Service SNOwpack TELemetry system) and modeled data (a downscaled version of the Parameter-elevation Regressions on Independent Slopes Model) for the period from 1951 to 2010. Over the study period, the five fens in the Sierra Nevada were found to be decreasing between 10% and 16% in delineated area. The climate analysis revealed significant increases through time in annual mean minimum temperature (Tmin) between 1951-1980 and 1981-2010. In addition, April 1 snow water equivalent and snowpack longevity also decreased between 1951-1980 and 1981-2010. For the fens in the Cascade Range, there were no discernible changes in delineated area. At these sites, increases in Tmin occurred only within the past 20-25 years and decreases in snowpack longevity were more subtle. A conceptual model is presented, which illustrates

  4. Short-Term Summer Inundation as a Measure to Counteract Acidification in Rich Fens.

    Mettrop, Ivan S; Cusell, Casper; Kooijman, Annemieke M; Lamers, Leon P M

    2015-01-01

    In regions with intensive agriculture, water level fluctuation in wetlands has generally become constricted within narrow limits. Water authorities are, however, considering the re-establishment of fluctuating water levels as a management tool in biodiverse, base-rich fens ('rich fens'). This includes temporary inundation with surface water from ditches, which may play an important role in counteracting acidification in order to conserve and restore biodiversity. Inundation may result in an increased acid neutralizing capacity (ANC) for two reasons: infiltration of base-rich inundation water into peat soils, and microbial alkalinity generation under anaerobic conditions. The main objectives of this study were to test whether short-term (2 weeks) summer inundation is more effective than short-term winter inundation to restore the ANC in the upper 10 cm of non-floating peat soils, and to explain potential differences. Large-scale field experiments were conducted for five years in base-rich fens and Sphagnum-dominated poor fens. Winter inundation did not result in increased porewater ANC, because infiltration was inhibited in the waterlogged peat and evapotranspiration rates were relatively low. Also, low temperatures limit microbial alkalinity generation. In summer, however, when temperature and evapotranspiration rates are higher, inundation resulted in increased porewater Ca and HCO3- concentrations, but only in areas with characteristic rich fen bryophytes. This increase was not only due to stronger infiltration into the soil, but also to higher microbial alkalinity generation under anaerobic conditions. In contrast, porewater ANC did not increase in Sphagnum-plots as a result of the ability of Sphagnum spp. to acidify their environment. In both rich and poor fens, flooding-induced P-mobilization remained sufficiently low to safeguard P-limited vegetation. NO3(-) and NH4(+) dynamics showed no considerable changes either. In conclusion, short-term summer inundation

  5. Short-Term Summer Inundation as a Measure to Counteract Acidification in Rich Fens.

    Ivan S Mettrop

    Full Text Available In regions with intensive agriculture, water level fluctuation in wetlands has generally become constricted within narrow limits. Water authorities are, however, considering the re-establishment of fluctuating water levels as a management tool in biodiverse, base-rich fens ('rich fens'. This includes temporary inundation with surface water from ditches, which may play an important role in counteracting acidification in order to conserve and restore biodiversity. Inundation may result in an increased acid neutralizing capacity (ANC for two reasons: infiltration of base-rich inundation water into peat soils, and microbial alkalinity generation under anaerobic conditions. The main objectives of this study were to test whether short-term (2 weeks summer inundation is more effective than short-term winter inundation to restore the ANC in the upper 10 cm of non-floating peat soils, and to explain potential differences. Large-scale field experiments were conducted for five years in base-rich fens and Sphagnum-dominated poor fens. Winter inundation did not result in increased porewater ANC, because infiltration was inhibited in the waterlogged peat and evapotranspiration rates were relatively low. Also, low temperatures limit microbial alkalinity generation. In summer, however, when temperature and evapotranspiration rates are higher, inundation resulted in increased porewater Ca and HCO3- concentrations, but only in areas with characteristic rich fen bryophytes. This increase was not only due to stronger infiltration into the soil, but also to higher microbial alkalinity generation under anaerobic conditions. In contrast, porewater ANC did not increase in Sphagnum-plots as a result of the ability of Sphagnum spp. to acidify their environment. In both rich and poor fens, flooding-induced P-mobilization remained sufficiently low to safeguard P-limited vegetation. NO3(- and NH4(+ dynamics showed no considerable changes either. In conclusion, short

  6. CO dissociation on magnetic Fen clusters

    Jedidi, Abdesslem

    2014-01-01

    This work theoretically investigates the CO dissociation on Fen nanoparticles, for n in the range of 1-65, focusing on size dependence in the context of the initial step of the Fischer-Tropsch reaction. CO adsorbs molecularly through its C-end on a triangular facet of the nanoparticle. Dissociation becomes easier when the cluster size increases. Then, the C atom is bonded to a square facet that is generated as a result of the adsorption if it does not yet exist in the bare cluster, while the O atom is adsorbed on a triangular facet. In the most stable situation, the two adsorbed atoms remain close together, both having in common one shared first-neighbor iron atom. There is a partial spin quenching of the neighboring Fe atoms, which become more positively charged than the other Fe atoms. The shared surface iron atom resembles a metal-cation from a complex. Despite the small size of the iron cluster considered, fluctuations due to specific configurations do not influence properties for n > 25 and global trends seem significant.

  7. A comparative proteomic analysis of the simple amino acid repeat distributions in Plasmodia reveals lineage specific amino acid selection.

    Andrew R Dalby

    Full Text Available BACKGROUND: Microsatellites have been used extensively in the field of comparative genomics. By studying microsatellites in coding regions we have a simple model of how genotypic changes undergo selection as they are directly expressed in the phenotype as altered proteins. The simplest of these tandem repeats in coding regions are the tri-nucleotide repeats which produce a repeat of a single amino acid when translated into proteins. Tri-nucleotide repeats are often disease associated, and are also known to be unstable to both expansion and contraction. This makes them sensitive markers for studying proteome evolution, in closely related species. RESULTS: The evolutionary history of the family of malarial causing parasites Plasmodia is complex because of the life-cycle of the organism, where it interacts with a number of different hosts and goes through a series of tissue specific stages. This study shows that the divergence between the primate and rodent malarial parasites has resulted in a lineage specific change in the simple amino acid repeat distribution that is correlated to A-T content. The paper also shows that this altered use of amino acids in SAARs is consistent with the repeat distributions being under selective pressure. CONCLUSIONS: The study shows that simple amino acid repeat distributions can be used to group related species and to examine their phylogenetic relationships. This study also shows that an outgroup species with a similar A-T content can be distinguished based only on the amino acid usage in repeats, and suggest that this might be a useful feature for proteome clustering. The lineage specific use of amino acids in repeat regions suggests that comparative studies of SAAR distributions between proteomes gives an insight into the mechanisms of expansion and the selective pressures acting on the organism.

  8. Electronic structure and magnetism of equiatomic FeN

    Kong, Yong

    2000-01-01

    In order to investigate the phase stability of equiatomic FeN compounds and the structure-dependent magnetic properties, the electronic structure and total energy of FeN with NaCl, ZnS and CsCl structures and various magnetic configurations are calculated using the first-principles TB-LMTO-ASA method. Among all the FeN phases considered, the antiferromagnetic NaCl structure with q=(00pi) is found to have the lowest energy at the theoretical equilibrium volume. However, the FM NaCl phase lies ...

  9. Lipidomic profiling of Saccharomyces cerevisiae and Zygosaccharomyces bailii reveals critical changes in lipid composition in response to acetic acid stress.

    Lina Lindberg

    Full Text Available When using microorganisms as cell factories in the production of bio-based fuels or chemicals from lignocellulosic hydrolysate, inhibitory concentrations of acetic acid, released from the biomass, reduce the production rate. The undissociated form of acetic acid enters the cell by passive diffusion across the lipid bilayer, mediating toxic effects inside the cell. In order to elucidate a possible link between lipid composition and acetic acid stress, the present study presents detailed lipidomic profiling of the major lipid species found in the plasma membrane, including glycerophospholipids, sphingolipids and sterols, in Saccharomyces cerevisiae (CEN.PK 113_7D and Zygosaccharomyces bailii (CBS7555 cultured with acetic acid. Detailed physiological characterization of the response of the two yeasts to acetic acid has also been performed in aerobic batch cultivations using bioreactors. Physiological characterization revealed, as expected, that Z. bailii is more tolerant to acetic acid than S. cerevisiae. Z. bailii grew at acetic acid concentrations above 24 g L(-1, while limited growth of S. cerevisiae was observed after 11 h when cultured with only 12 g L(-1 acetic acid. Detailed lipidomic profiling using electrospray ionization, multiple-reaction-monitoring mass spectrometry (ESI-MRM-MS showed remarkable changes in the glycerophospholipid composition of Z. bailii, including an increase in saturated glycerophospholipids and considerable increases in complex sphingolipids in both S. cerevisiae (IPC 6.2×, MIPC 9.1×, M(IP2C 2.2× and Z. bailii (IPC 4.9×, MIPC 2.7×, M(IP2C 2.7×, when cultured with acetic acid. In addition, the basal level of complex sphingolipids was significantly higher in Z. bailii than in S. cerevisiae, further emphasizing the proposed link between lipid saturation, high sphingolipid levels and acetic acid tolerance. The results also suggest that acetic acid tolerance is associated with the ability of a given strain to

  10. Dietary supplementation with arachidonic acid in tilapia (Oreochromis mossambicus) reveals physiological effects not mediated by prostaglandins.

    Anholt, R.D. van; Spanings, F.A.T.; Koven, W.M.; Wendelaar Bonga, S.E.

    2004-01-01

    This study aims to clarify the role of the polyunsaturated fatty acid arachidonic acid (ArA, 20:4n-6) in the stress response of Mozambique tilapia (Oreochromis mossambicus). ArA is converted into eicosanoids, including prostaglandins, which can influence the response to stressors. Tilapia, a species

  11. Analysis and Prediction of Annual Runoff for Fen River Basin

    Zhang Kai; Yang Yonggang; Qin Zuodong; Li Hongjian; Meng Zhilong

    2013-01-01

    The runoff characteristics of Fen river basin was analyzed first. According to the runoff data of 1960-2000, autocorrelation analysis method was used to determine model input variables and then radial basis function artificial neural network was used to recognize the relationship between previous annual runoff and later annual runoff. The developed prediction model was used to predict the annual runoff of 2001 to 2015 of Fen river basin. The result shows that: the predicted annual runoff was ...

  12. Metabolomics reveals amino acids contribute to variation in response to simvastatin treatment.

    Miles Trupp

    Full Text Available UNLABELLED: Statins are widely prescribed for reducing LDL-cholesterol (C and risk for cardiovascular disease (CVD, but there is considerable variation in therapeutic response. We used a gas chromatography-time-of-flight mass-spectrometry-based metabolomics platform to evaluate global effects of simvastatin on intermediary metabolism. Analyses were conducted in 148 participants in the Cholesterol and Pharmacogenetics study who were profiled pre and six weeks post treatment with 40 mg/day simvastatin: 100 randomly selected from the full range of the LDL-C response distribution and 24 each from the top and bottom 10% of this distribution ("good" and "poor" responders, respectively. The metabolic signature of drug exposure in the full range of responders included essential amino acids, lauric acid (p<0.0055, q<0.055, and alpha-tocopherol (p<0.0003, q<0.017. Using the HumanCyc database and pathway enrichment analysis, we observed that the metabolites of drug exposure were enriched for the pathway class amino acid degradation (p<0.0032. Metabolites whose change correlated with LDL-C lowering response to simvastatin in the full range responders included cystine, urea cycle intermediates, and the dibasic amino acids ornithine, citrulline and lysine. These dibasic amino acids share plasma membrane transporters with arginine, the rate-limiting substrate for nitric oxide synthase (NOS, a critical mediator of cardiovascular health. Baseline metabolic profiles of the good and poor responders were analyzed by orthogonal partial least square discriminant analysis so as to determine the metabolites that best separated the two response groups and could be predictive of LDL-C response. Among these were xanthine, 2-hydroxyvaleric acid, succinic acid, stearic acid, and fructose. Together, the findings from this study indicate that clusters of metabolites involved in multiple pathways not directly connected with cholesterol metabolism may play a role in modulating

  13. The Crystal Structure of the Adenylation Enzyme VinN Reveals a Unique β-Amino Acid Recognition Mechanism*

    Miyanaga, Akimasa; Cieślak, Jolanta; Shinohara, Yuji; Kudo, Fumitaka; Eguchi, Tadashi

    2014-01-01

    Adenylation enzymes play important roles in the biosynthesis and degradation of primary and secondary metabolites. Mechanistic insights into the recognition of α-amino acid substrates have been obtained for α-amino acid adenylation enzymes. The Asp residue is invariant and is essential for the stabilization of the α-amino group of the substrate. In contrast, the β-amino acid recognition mechanism of adenylation enzymes is still unclear despite the importance of β-amino acid activation for the biosynthesis of various natural products. Herein, we report the crystal structure of the stand-alone adenylation enzyme VinN, which specifically activates (2S,3S)-3-methylaspartate (3-MeAsp) in vicenistatin biosynthesis. VinN has an overall structure similar to that of other adenylation enzymes. The structure of the complex with 3-MeAsp revealed that a conserved Asp230 residue is used in the recognition of the β-amino group of 3-MeAsp similar to α-amino acid adenylation enzymes. A mutational analysis and structural comparison with α-amino acid adenylation enzymes showed that the substrate-binding pocket of VinN has a unique architecture to accommodate 3-MeAsp as a β-amino acid substrate. Thus, the VinN structure allows the first visualization of the interaction of an adenylation enzyme with a β-amino acid and provides new mechanistic insights into the selective recognition of β-amino acids in this family of enzymes. PMID:25246523

  14. The crystal structure of the adenylation enzyme VinN reveals a unique β-amino acid recognition mechanism.

    Miyanaga, Akimasa; Cieślak, Jolanta; Shinohara, Yuji; Kudo, Fumitaka; Eguchi, Tadashi

    2014-11-01

    Adenylation enzymes play important roles in the biosynthesis and degradation of primary and secondary metabolites. Mechanistic insights into the recognition of α-amino acid substrates have been obtained for α-amino acid adenylation enzymes. The Asp residue is invariant and is essential for the stabilization of the α-amino group of the substrate. In contrast, the β-amino acid recognition mechanism of adenylation enzymes is still unclear despite the importance of β-amino acid activation for the biosynthesis of various natural products. Herein, we report the crystal structure of the stand-alone adenylation enzyme VinN, which specifically activates (2S,3S)-3-methylaspartate (3-MeAsp) in vicenistatin biosynthesis. VinN has an overall structure similar to that of other adenylation enzymes. The structure of the complex with 3-MeAsp revealed that a conserved Asp(230) residue is used in the recognition of the β-amino group of 3-MeAsp similar to α-amino acid adenylation enzymes. A mutational analysis and structural comparison with α-amino acid adenylation enzymes showed that the substrate-binding pocket of VinN has a unique architecture to accommodate 3-MeAsp as a β-amino acid substrate. Thus, the VinN structure allows the first visualization of the interaction of an adenylation enzyme with a β-amino acid and provides new mechanistic insights into the selective recognition of β-amino acids in this family of enzymes. PMID:25246523

  15. Impacts of oil sands process water on fen plants: Implications for plant selection in required reclamation projects

    Fen plant growth in peat contaminated with groundwater discharges of oil sands process water (OSPW) was assessed in a greenhouse over two growing seasons. Three treatments (non-diluted OSPW, diluted OSPW and rainwater) were tested on five vascular plants and four mosses. All vascular plants tested can grow in salinity and naphthenic acids levels currently produced by oil sands activity in northwestern Canada. No stress sign was observed after both seasons. Because of plant characteristics, Carex species (C. atherodes and C. utriculata) and Triglochin maritima would be more useful for rapidly restoring vegetation and creating a new peat-accumulating system. Groundwater discharge of OSPW proved detrimental to mosses under dry conditions and ensuring adequate water levels would be crucial in fen creation following oil sands exploitation. Campylium stellatum would be the best choice to grow in contaminated areas and Bryum pseudotriquetrum might be interesting as it has spontaneously regenerated in all treatments. - Highlights: ► Fen plant growth was assessed under groundwater discharges of oil sands process water. ► Sedge and grass species were not stressed after two growing seasons in greenhouse. ► Carex species and Triglochin maritima would be helpful in created contaminated fens. ► In dry conditions, contaminated groundwater discharge was detrimental for mosses. ► Campylium stellatum would be the best choice in created fens with contaminated water. - Sedges and grasses tolerated the contact with oil sands process water and could probably grow well in contaminated created fens, but mosses were particularly affected under dry conditions.

  16. Mechanistic Modeling Reveals the Critical Knowledge Gaps in Bile Acid-Mediated DILI.

    Woodhead, J L; Yang, K; Brouwer, K L R; Siler, S Q; Stahl, S H; Ambroso, J L; Baker, D; Watkins, P B; Howell, B A

    2014-01-01

    Bile salt export pump (BSEP) inhibition has been proposed to be an important mechanism for drug-induced liver injury (DILI). Modeling can prioritize knowledge gaps concerning bile acid (BA) homeostasis and thus help guide experimentation. A submodel of BA homeostasis in rats and humans was constructed within DILIsym, a mechanistic model of DILI. In vivo experiments in rats with glibenclamide were conducted, and data from these experiments were used to validate the model. The behavior of DILIsym was analyzed in the presence of a simulated theoretical BSEP inhibitor. BSEP inhibition in humans is predicted to increase liver concentrations of conjugated chenodeoxycholic acid (CDCA) and sulfate-conjugated lithocholic acid (LCA) while the concentration of other liver BAs remains constant or decreases. On the basis of a sensitivity analysis, the most important unknowns are the level of BSEP expression, the amount of intestinal synthesis of LCA, and the magnitude of farnesoid-X nuclear receptor (FXR)-mediated regulation. PMID:25006780

  17. Decoding genome-wide GadEWX-transcriptional regulatory networks reveals multifaceted cellular responses to acid stress in Escherichia coli

    Seo, Sang Woo; Kim, Donghyuk; O'Brien, Edward J.;

    2015-01-01

    . We demonstrate that GadEWX directly and coherently regulate several proton-generating/consuming enzymes with pairs of negative-feedback loops for pH homeostasis. In addition, GadEWX regulate genes with assorted functions, including molecular chaperones, acid resistance, stress response and other...... comprehensively reconstruct the genome-wide GadEWX transcriptional regulatory network and RpoS involvement in E. coli K-12 MG1655 under acidic stress. Integrative data analysis reveals that GadEWX regulons consist of 45 genes in 31 transcription units and 28 of these genes were associated with RpoS-binding sites...... regulatory activities. These results show how GadEWX simultaneously coordinate many cellular processes to produce the overall response of E. coli to acid stress....

  18. CAPSAICIN AND ASCORBIC ACID VARIABILITY IN CHILLI AND PAPRIKA CULTIVARS AS REVEALED BY HPLC ANALYSIS

    Samuel Tilahun

    2013-08-01

    Full Text Available Capsaicin and ascorbic acid contents of seven Indian peppers varieties/accessions from Capsicum annuum (CA 97, CCH, K1, KTPL19, Arka Abhir and Bayadagi Kaddi and C. frutescens (CF1 species were determined using High Performance Liquid Chromatography (HPLC. Based on their pungency value, all the chilli accession/varieties (CA 97, CCH, K1, and CF 1 were classified as highly pungent peppers. The accession CF1 showed the highest concentration of capsaicin (445mg 100g -1 DW with corresponding pungency value of 71,200 SHUs and Arka Abhir variety showed the lowest capsaicin concentration (29mg 100g -1 DW with 4,672 SHUs of pungency value. Similarly, Bayadaggi kaddi variety showed the highest ascorbic acid content (189 mg/100 FW and the accession CA 97 showed the lowest ascorbic acid contents (55.3 mg/100 FW. The variability in capsaicin and ascorbic acid content presented in the pepper germplasm can be exploited for breeding cultivars with improved nutritional qualities. Moreover, CF1and Bayadagi kaddi can be used as a potential source for capsaicin and vitamin C, respectively.

  19. Six Tissue Transcriptomics Reveals Specific Immune Suppression in Spleen by Dietary Polyunsaturated Fatty Acids

    Gabrielsson, Britt G.; Peris, Eduard; Nookaew, Intawat; Grahnemo, Louise; Sandberg, Ann-Sofie; Wernstedt Asterholm, Ingrid; Jansson, John-Olov; Nielsen, Jens

    2016-01-01

    Dietary polyunsaturated fatty acids (PUFA) are suggested to modulate immune function, but the effects of dietary fatty acids composition on gene expression patterns in immune organs have not been fully characterized. In the current study we investigated how dietary fatty acids composition affects the total transcriptome profile, and especially, immune related genes in two immune organs, spleen (SPL) and bone marrow cells (BMC). Four tissues with metabolic function, skeletal muscle (SKM), white adipose tissue (WAT), brown adipose tissue (BAT), and liver (LIV), were investigated as a comparison. Following 8 weeks on low fat diet (LFD), high fat diet (HFD) rich in saturated fatty acids (HFD-S), or HFD rich in PUFA (HFD-P), tissue transcriptomics were analyzed by microarray and metabolic health assessed by fasting blood glucose level, HOMA-IR index, oral glucose tolerance test as well as quantification of crown-like structures in WAT. HFD-P corrected the metabolic phenotype induced by HFD-S. Interestingly, SKM and BMC were relatively inert to the diets, whereas the two adipose tissues (WAT and BAT) were mainly affected by HFD per se (both HFD-S and HFD-P). In particular, WAT gene expression was driven closer to that of the immune organs SPL and BMC by HFDs. The LIV exhibited different responses to both of the HFDs. Surprisingly, the spleen showed a major response to HFD-P (82 genes differed from LFD, mostly immune genes), while it was not affected at all by HFD-S (0 genes differed from LFD). In conclusion, the quantity and composition of dietary fatty acids affected the transcriptome in distinct manners in different organs. Remarkably, dietary PUFA, but not saturated fat, prompted a specific regulation of immune related genes in the spleen, opening the possibility that PUFA can regulate immune function by influencing gene expression in this organ. PMID:27166587

  20. Six Tissue Transcriptomics Reveals Specific Immune Suppression in Spleen by Dietary Polyunsaturated Fatty Acids.

    Sara L Svahn

    Full Text Available Dietary polyunsaturated fatty acids (PUFA are suggested to modulate immune function, but the effects of dietary fatty acids composition on gene expression patterns in immune organs have not been fully characterized. In the current study we investigated how dietary fatty acids composition affects the total transcriptome profile, and especially, immune related genes in two immune organs, spleen (SPL and bone marrow cells (BMC. Four tissues with metabolic function, skeletal muscle (SKM, white adipose tissue (WAT, brown adipose tissue (BAT, and liver (LIV, were investigated as a comparison. Following 8 weeks on low fat diet (LFD, high fat diet (HFD rich in saturated fatty acids (HFD-S, or HFD rich in PUFA (HFD-P, tissue transcriptomics were analyzed by microarray and metabolic health assessed by fasting blood glucose level, HOMA-IR index, oral glucose tolerance test as well as quantification of crown-like structures in WAT. HFD-P corrected the metabolic phenotype induced by HFD-S. Interestingly, SKM and BMC were relatively inert to the diets, whereas the two adipose tissues (WAT and BAT were mainly affected by HFD per se (both HFD-S and HFD-P. In particular, WAT gene expression was driven closer to that of the immune organs SPL and BMC by HFDs. The LIV exhibited different responses to both of the HFDs. Surprisingly, the spleen showed a major response to HFD-P (82 genes differed from LFD, mostly immune genes, while it was not affected at all by HFD-S (0 genes differed from LFD. In conclusion, the quantity and composition of dietary fatty acids affected the transcriptome in distinct manners in different organs. Remarkably, dietary PUFA, but not saturated fat, prompted a specific regulation of immune related genes in the spleen, opening the possibility that PUFA can regulate immune function by influencing gene expression in this organ.

  1. Six Tissue Transcriptomics Reveals Specific Immune Suppression in Spleen by Dietary Polyunsaturated Fatty Acids.

    Svahn, Sara L; Väremo, Leif; Gabrielsson, Britt G; Peris, Eduard; Nookaew, Intawat; Grahnemo, Louise; Sandberg, Ann-Sofie; Wernstedt Asterholm, Ingrid; Jansson, John-Olov; Nielsen, Jens; Johansson, Maria E

    2016-01-01

    Dietary polyunsaturated fatty acids (PUFA) are suggested to modulate immune function, but the effects of dietary fatty acids composition on gene expression patterns in immune organs have not been fully characterized. In the current study we investigated how dietary fatty acids composition affects the total transcriptome profile, and especially, immune related genes in two immune organs, spleen (SPL) and bone marrow cells (BMC). Four tissues with metabolic function, skeletal muscle (SKM), white adipose tissue (WAT), brown adipose tissue (BAT), and liver (LIV), were investigated as a comparison. Following 8 weeks on low fat diet (LFD), high fat diet (HFD) rich in saturated fatty acids (HFD-S), or HFD rich in PUFA (HFD-P), tissue transcriptomics were analyzed by microarray and metabolic health assessed by fasting blood glucose level, HOMA-IR index, oral glucose tolerance test as well as quantification of crown-like structures in WAT. HFD-P corrected the metabolic phenotype induced by HFD-S. Interestingly, SKM and BMC were relatively inert to the diets, whereas the two adipose tissues (WAT and BAT) were mainly affected by HFD per se (both HFD-S and HFD-P). In particular, WAT gene expression was driven closer to that of the immune organs SPL and BMC by HFDs. The LIV exhibited different responses to both of the HFDs. Surprisingly, the spleen showed a major response to HFD-P (82 genes differed from LFD, mostly immune genes), while it was not affected at all by HFD-S (0 genes differed from LFD). In conclusion, the quantity and composition of dietary fatty acids affected the transcriptome in distinct manners in different organs. Remarkably, dietary PUFA, but not saturated fat, prompted a specific regulation of immune related genes in the spleen, opening the possibility that PUFA can regulate immune function by influencing gene expression in this organ. PMID:27166587

  2. Metabolic regulation of trisporic acid on Blakeslea trispora revealed by a GC-MS-based metabolomic approach.

    Jie Sun

    Full Text Available The zygomycete Blakeslea trispora is used commercially as natural source of â-carotene. Trisporic acid (TA is secreted from the mycelium of B. trispora during mating between heterothallic strains and is considered as a mediator of the regulation of mating processes and an enhancer of carotene biosynthesis. Gas chromatography-mass spectrometry and multivariate analysis were employed to investigate TA-associated intracellular biochemical changes in B. trispora. By principal component analysis, the differential metabolites discriminating the control groups from the TA-treated groups were found, which were also confirmed by the subsequent hierarchical cluster analysis. The results indicate that TA is a global regulator and its main effects at the metabolic level are reflected on the content changes in several fatty acids, carbohydrates, and amino acids. The carbon metabolism and fatty acids synthesis are sensitive to TA addition. Glycerol, glutamine, and ã-aminobutyrate might play important roles in the regulation of TA. Complemented by two-dimensional electrophoresis, the results indicate that the actions of TA at the metabolic level involve multiple metabolic processes, such as glycolysis and the bypass of the classical tricarboxylic acid cycle. These results reveal that the metabolomics strategy is a powerful tool to gain insight into the mechanism of a microorganism's cellular response to signal inducers at the metabolic level.

  3. Sulphur Kβ emission spectra reveal protonation states of aqueous sulfuric acid

    Niskanen, Johannes; Sahle, Christoph J.; Ruotsalainen, Kari O.; Müller, Harald; Kavčič, Matjaž; Žitnik, Matjaž; Bučar, Klemen; Petric, Marko; Hakala, Mikko; Huotari, Simo

    2016-02-01

    In this paper we report an X-ray emission study of bulk aqueous sulfuric acid. Throughout the range of molarities from 1 M to 18 M the sulfur Kβ emission spectra from H2SO4 (aq) depend on the molar fractions and related deprotonation of H2SO4. We compare the experimental results with results from emission spectrum calculations based on atomic structures of single molecules and structures from ab initio molecular dynamics simulations. We show that the S Kβ emission spectrum is a sensitive probe of the protonation state of the acid molecules. Using non-negative matrix factorization we are able to extract the fractions of different protonation states in the spectra, and the results are in good agreement with the simulation for the higher part of the concentration range.

  4. Acetic acid bacteria genomes reveal functional traits for adaptation to life in insect guts

    B. Chouaia; Gaiarsa, S.; Crotti, E.; Comandatore, F.; Degli Esposti, M.; I. RICCI; Alma, A.; Favia, G.; Bandi, C.; D. Daffonchio

    2014-01-01

    Acetic acid bacteria (AAB) live in sugar rich environments, including food matrices, plant tissues, and the gut of sugar-feeding insects. By comparing the newly sequenced genomes of Asaia platycodi and Saccharibacter sp., symbionts of Anopheles stephensi and Apis mellifera, respectively, with those of 14 other AAB, we provide a genomic view of the evolutionary pattern of this bacterial group and clues on traits that explain the success of AAB as insect symbionts. A specific pre-adaptive trait...

  5. Structure of Human Acid Sphingomyelinase Reveals the Role of the Saposin Domain in Activating Substrate Hydrolysis.

    Xiong, Zi-Jian; Huang, Jingjing; Poda, Gennady; Pomès, Régis; Privé, Gilbert G

    2016-07-31

    Acid sphingomyelinase (ASM) is a lysosomal phosphodiesterase that catalyzes the hydrolysis of sphingomyelin to produce ceramide and phosphocholine. While other lysosomal sphingolipid hydrolases require a saposin activator protein for full activity, the ASM polypeptide incorporates a built-in N-terminal saposin domain and does not require an external activator protein. Here, we report the crystal structure of human ASM and describe the organization of the three main regions of the enzyme: the N-terminal saposin domain, the proline-rich connector, and the catalytic domain. The saposin domain is tightly associated along an edge of the large, bowl-shaped catalytic domain and adopts an open form that exposes a hydrophobic concave surface approximately 30Å from the catalytic center. The calculated electrostatic potential of the enzyme is electropositive at the acidic pH of the lysosome, consistent with the strict requirement for the presence of acidic lipids in target membranes. Docking studies indicate that sphingomyelin binds with the ceramide-phosphate group positioned at the binuclear zinc center and molecular dynamic simulations indicate that the intrinsic flexibility of the saposin domain is important for monomer-dimer exchange and for membrane interactions. Overall, ASM uses a combination of electrostatic and hydrophobic interactions to cause local disruptions of target bilayers in order to bring the lipid headgroup to the catalytic center in a membrane-bound reaction. PMID:27349982

  6. beta-Keratins in crocodiles reveal amino acid homology with avian keratins.

    Ye, Changjiang; Wu, Xiaobing; Yan, Peng; Amato, George

    2010-03-01

    The DNA sequences encoding beta-keratin have been obtained from Marsh Mugger (Crocodylus palustris) and Orinoco Crocodiles (Crocodylus intermedius). Through the deduced amino acid sequence, these proteins are rich in glycine, proline and serine. The central region of the proteins are composed of two beta-folded regions and show a high degree of identity with beta-keratins of aves and squamates. This central part is thought to be the site of polymerization to build the framework of beta-keratin filaments. It is believed that the beta-keratins in reptiles and birds share a common ancestry. Near the C-terminal, these beta-keratins contain a peptide rich in glycine-X and glycine-X-X, and the distinctive feature of the region is some 12-amino acid repeats, which are similar to the 13-amino acid repeats in chick scale keratin but absent from avian feather keratin. From our phylogenetic analysis, the beta-keratins in crocodile have a closer relationship with avian keratins than the other keratins in reptiles. PMID:19266314

  7. Untangling the Effect of Fatty Acid Addition at Species Level Revealed Different Transcriptional Responses of the Biogas Microbial Community Members.

    Treu, Laura; Campanaro, Stefano; Kougias, Panagiotis G; Zhu, Xinyu; Angelidaki, Irini

    2016-06-01

    In the present study, RNA-sequencing was used to elucidate the change of anaerobic digestion metatranscriptome after long chain fatty acids (oleate) exposure. To explore the general transcriptional behavior of the microbiome, the analysis was first performed on shotgun reads without considering a reference metagenome. As a second step, RNA reads were aligned on the genes encoded by the microbial community, revealing the expression of more than 51 000 different transcripts. The present study is the first research which was able to dissect the transcriptional behavior at a single species level by considering the 106 microbial genomes previously identified. The exploration of the metabolic pathways confirmed the importance of Syntrophomonas species in fatty acids degradation, and also highlighted the presence of protective mechanisms toward the long chain fatty acid effects in bacteria belonging to Clostridiales, Rykenellaceae, and in species of the genera Halothermothrix and Anaerobaculum. Additionally, an interesting transcriptional activation of the chemotaxis genes was evidenced in seven species belonging to Clostridia, Halothermothrix, and Tepidanaerobacter. Surprisingly, methanogens revealed a very versatile behavior different from each other, even among similar species of the Methanoculleus genus, while a strong increase of the expression level in Methanosarcina sp. was evidenced after oleate addition. PMID:27154312

  8. Analysis of olfactory sensitivity in rainbow trout (Oncorhynchus mykiss) reveals their ability to detect lactic acid, pyruvic acid and four B vitamins.

    Valdés, Joaquín; Olivares, Jesús; Ponce, Daniela; Schmachtenberg, Oliver

    2015-08-01

    Salmonid fishes like the rainbow trout Oncorhynchus mykiss have a highly developed olfactory sense that allows them to perceive some odorants at very low concentrations, such as certain amino acids and bile salts. Previous behavioral and electrophysiological studies in salmonids have shown strong responses to human skin odor. Because this stimulus represents a complex and heterogeneous mixture of components, we sought to determine which odorants contribute to the sensitive detection of human skin odor by salmonids. In vivo electroolfactogram recordings in O. mykiss revealed lactic acid, pyruvic acid and two B vitamins, thiamine and riboflavin, as novel, potent odorants which triggered responses at nanomolar concentrations. Two more B vitamins, nicotinic and pantothenic acid, were detected at micromolar concentrations. These compounds share important roles in cellular energy metabolism, supporting an original role in food search and feeding behavior of this species and most likely other fishes. The olfactory detection of B vitamins by salmonids represents a new paradigm in chemosensation, warranting further investigation in other teleosts. PMID:25864178

  9. Warming increases isoprene emissions from an arctic fen.

    Lindwall, Frida; Svendsen, Sophie Sylvest; Nielsen, Cecilie Skov; Michelsen, Anders; Rinnan, Riikka

    2016-05-15

    Emissions of biogenic volatile organic compounds (BVOCs) from dry ecosystems at high latitudes respond strongly to small increases in temperature, and warm canopy surface temperatures drive emissions to higher levels than expected. However, it is not known whether emissions from wetlands, cooled by through-flowing water and higher evapotranspiration show similar response to warming as in drier ecosystems. Climate change will cause parts of the Arctic to experience increased snow fall, which delays the start of the growing season, insulates soil from low temperatures in winter, and increases soil moisture and possibly nutrient availability. Currently the effects of increasing snow depth on BVOC emissions are unknown. BVOC emissions were measured in situ across the growing season in a climate experiment, which used open top chambers to increase temperature and snow fences to increase winter snow depth. The treatments were arranged in a full factorial design. Measurements took place during two growing seasons in a fen ecosystem in west Greenland. BVOC samples collected by an enclosure technique in adsorbent cartridges were analysed using gas chromatography-mass spectrometry. Gross ecosystem production (GEP) was measured with a closed chamber technique, to reveal any immediate effect of treatments on photosynthesis, which could further influence BVOC emissions. Isoprene made up 84-92% of the emitted BVOCs. Isoprene emission increased 240 and 340% due to an increase in temperature of 1.3 and 1.6°C in 2014 and 2015, respectively. Isoprene emissions were 25 times higher in 2015 than in 2014 most likely due to a 2.4°C higher canopy air temperature during sampling in 2015. Snow addition had no significant effect on isoprene emissions even though GEP was increased by 24%. Arctic BVOC emissions respond strongly to rising temperatures in wet ecosystems, suggesting a large increase in arctic emissions in a future warmer climate. PMID:26933965

  10. Evolution reveals a glutathione-dependent mechanism of 3-hydroxypropionic acid tolerance

    Kildegaard, Kanchana Rueksomtawin; Hallström, Björn M.; Blicher, Thomas H.;

    2014-01-01

    , preferably at low pH. Through adaptive laboratory evolution we selected S. cerevisiae strains with improved tolerance to 3HP at pH 3.5.Genome sequencing followed by functional analysis identified the causal mutation in SFA1 gene encoding S-(hydroxymethyl)glutathione dehydrogenase. Based on our findings, we...... propose that 3HP toxicity is mediated by3-hydroxypropionic aldehyde (reuterin) and that glutathione-dependent reactions are used for reuterin detoxification. The identified molecular response to 3HP and reuterin may well be a general mechanism for handling resistance to organic acid and aldehydes by...

  11. Fenólicos totais e capacidade antioxidante in vitro de polpas de frutos tropicais

    Luanne Morais Vieira

    2011-09-01

    Full Text Available O consumo de frutos e suas polpas tem sido muito recomendado por seu valor nutricional, alto teor de fibras, vitamina C e carotenoides. Trabalhos recentes têm apontado esses alimentos como fontes de compostos fenólicos com ação antioxidante, portanto sequestradores de radicais livres, com ação protetora contra o surgimento e/ou desenvolvimento de processos degenerativos que conduzem a doenças crônicas não transmissíveis. Devido à crescente comercialização e consumo de polpas de frutas no Brasil, especialmente na cidade de Teresina-Piauí, este trabalho selecionou um grupo de polpas de frutos de elevado consumo local para avaliação do teor de fenólicos totais e da atividade antioxidante in vitro pelo método de captura de radicais livres: DPPH (radical 1,1-diphenil-2-picrilhydrazil e ABTS (radical 2,2'azinobis(3-ethylbenzthiazoline-6-sulfonic acid. Os frutos selecionados foram: Acerola (Malpighia emarginata DC., Bacuri (Platonia insignis Mart., Cajá (Spondias mombin L., Caju (Anacardium occidentale, Goiaba(Psidium guajava e Tamarindo (Tamarindus indica L.. Os teores de fenólicos totais encontrados nas polpascongeladas destes frutos exibiram quantidades relevantes de polifenóis, destacando-se a polpa de acerola com 835,25 ± 32,44 e 449,63 ± 10,24 mg /100g nos extratos aquosos e hidroalcoólicos, respectivamente, seguido pela polpa de caju com 201,61 ± 19,15 e 165,07 ± 4,10 mg /100g. As polpas de bacuri e tamarindo foram as que apresentaram os menores teores de fenólicos totais. Com relação à atividade antioxidante in vitro, os melhores resultados foram encontrados para os extratos aquosos e hidroalcoólicos das polpas de acerola, caju e goiaba. A capacidade antioxidante destas polpas (EC50 em µg/mL variou de 24,42 a 413,36 e de 1,74 a 259,18 para os extratos aquosos e hidroalcoólicos, respectivamente. Utilizando o radical ABTS, a atividade antioxidante para essas mesmas polpas de frutas apresentou valores TEAC que

  12. Ácidos fenólicos como antioxidantes

    SOARES Sergio Eduardo

    2002-01-01

    Os compostos fenólicos têm sido muito estudados devido a sua influência na qualidade dos alimentos. Englobam uma gama enorme de substâncias, entre elas os ácidos fenólicos, os quais, por sua constituição química, possuem propriedades antioxidantes. Assim, a presente revisão procura reunir diversos estudos que avaliaram o potencial antioxidante dos ácidos fenólicos na conservação de alimentos lipídicos. Além disso, são reunidos também estudos sobre a ação antioxidante destes compostos no siste...

  13. Crystallographic analysis reveals the structural basis of the high-affinity binding of iophenoxic acid to human serum albumin

    Chung Chun-wa

    2011-04-01

    Full Text Available Abstract Background Iophenoxic acid is an iodinated radiocontrast agent that was withdrawn from clinical use because of its exceptionally long half-life in the body, which was due in part to its high-affinity binding to human serum albumin (HSA. It was replaced by Iopanoic acid, which has an amino rather than a hydroxyl group at position 3 on the iodinated benzyl ring and, as a result, binds to albumin with lower affinity and is excreted more rapidly from the body. To understand how iophenoxic acid binds so tightly to albumin, we wanted to examine the structural basis of its interaction with HSA. Results We have determined the co-crystal structure of HSA in complex with iophenoxic acid at 2.75 Å resolution, revealing a total of four binding sites, two of which - in drugs sites 1 and 2 on the protein - are likely to be occupied at clinical doses. High-affinity binding of iophenoxic acid occurs at drug site 1. The structure reveals that polar and apolar groups on the compound are involved in its interactions with drug site 1. In particular, the 3-hydroxyl group makes three hydrogen bonds with the side-chains of Tyr 150 and Arg 257. The mode of binding to drug site 2 is similar except for the absence of a binding partner for the hydroxyl group on the benzyl ring of the compound. Conclusions The HSA-iophenoxic acid structure indicates that high-affinity binding to drug site 1 is likely to be due to extensive desolvation of the compound, coupled with the ability of the binding pocket to provide a full set of salt-bridging or hydrogen bonding partners for its polar groups. Consistent with this interpretation, the structure also suggests that the lower-affinity binding of iopanoic acid arises because replacement of the 3-hydroxyl by an amino group eliminates hydrogen bonding to Arg 257. This finding underscores the importance of polar interactions in high-affinity binding to albumin.

  14. Down-regulation of the Caffeic acid O-methyltransferase Gene in Switchgrass Reveals a Novel Monolignol Analog

    Tschaplinski, Timothy J [ORNL; Standaert, Robert F [ORNL; Engle, Nancy L [ORNL; Martin, Madhavi Z [ORNL; Sangha, Amandeep K [ORNL; Parks, Jerry M [ORNL; Smith, Jeremy C [ORNL; Samuel, Reichel [ORNL; Pu, Yunqiao [ORNL; Ragauskas, A J [Georgia Institute of Technology; Hamilton, Choo Yieng [ORNL; Fu, Chunxiang [Noble Foundation; Wang, Zeng-Yu [Noble Foundation; Davison, Brian H [ORNL; Dixon, Richard A [Noble Foundation; Mielenz, Jonathan R [ORNL

    2012-01-01

    Down-regulation of the caffeic acid 3-O-methyltransferase (COMT) gene in the lignin biosynthetic pathway of switchgrass (Panicum virgatum) resulted in cell walls of transgenic plants releasing more constituent sugars after pretreatment by dilute acid and treatment with glycosyl hydrolases from an added enzyme preparation and from Clostridium thermocellum. Fermentation of both wild-type and transgenic switchgrass after milder hot water pretreatment with no water washing showed that only the transgenic switchgrass inhibited C. thermocellum. Gas chromatography-mass spectrometry-based metabolomics were undertaken on cell wall aqueous extracts to determine the nature of the microbial inhibitors, confirming the increased concentration of a number of phenolic acids and aldehydes that are known inhibitors of fermentation. Metabolomic analyses of the transgenic biomass additionally revealed the presence of a novel monolignol-like metabolite, identified as trans-3, 4-dimethoxy-5-hydroxycinnamyl alcohol (iso-sinapyl alcohol) in both non-pretreated, as well as hot water pretreated samples. Although there was no indication that iso-sinapyl alcohol was integrated into the cell wall, diversion of substrates from sinapyl alcohol to free iso-sinapyl alcohol, its glucoside, and associated upstream lignin pathway changes, including increased phenolic aldehydes and acids, are associated with more facile cell wall deconstruction, and to the observed inhibitory effect on microbial growth.

  15. Phase transformations in interstitial Fe-N alloys

    Liapina, T.

    2005-04-15

    Nitriding is a prominent thermochemical heat-treatment procedure leading to various types of surface property improvements of the treated iron and steel. Many questions regarding even very basic properties of these compound layers and the relevant nitride phases are still open. Some of these open questions related with the behaviour of iron nitrides and, in particular, of iron nitride compound layers occurring below the usual process temperatures are addressed to in this thesis, as relevant e.g. for the cooling procedure after nitriding. The most important iron nitrides occurring in iron-nitride compound layers are the {gamma}'- and {epsilon}-phases in the Fe-N system. It is shown that for relatively low nitrogen contents of epsilon-iron nitrides (around Fe{sub 3}N) the cooling rate upon going down from an elevated annealing temperature to room temperature has a significant effect on the lattice parameters. X-ray and neutron diffraction analysis revealed that the lattice parameter values observed after fast cooling are affected by the higher degree of nitrogen disorder at elevated temperature, thus changing the c/a ratio. New relations between the lattice parameters of {epsilon}-iron nitrides and the nitrogen content are suggested for different types of cooling. The investigation by TEM of the decomposition upon annealing (633 K, 673 K) of initially homogeneous {epsilon}-Fe{sub 3}N powders revealed that the {gamma}'-formation occurs in only a few powder particles in a grain-like form. Moreover, diffraction line-profile analysis revealed N transport occurring from particle to particle, leading to inhomogeneities of N content in the epsilon-phase. It was shown that {gamma}'-iron nitride formation can occur by backwards growth of the existing {gamma}'-sublayer at the cost of the {epsilon}-sublayer increasing N concentration in the {epsilon}-layer. Another process, which may additionally occur in the compound layer upon annealing, is diffusion of N

  16. Structure of Vibrio cholerae ToxT reveals a mechanism for fatty acid regulation of virulence genes

    Lowden, Michael J.; Skorupski, Karen; Pellegrini, Maria; Chiorazzo, Michael G.; Taylor, Ronald K.; Kull, F. Jon (Dartmouth)

    2010-03-04

    Cholera is an acute intestinal infection caused by the bacterium Vibrio cholerae. In order for V. cholerae to cause disease, it must produce two virulence factors, the toxin-coregulated pilus (TCP) and cholera toxin (CT), whose expression is controlled by a transcriptional cascade culminating with the expression of the AraC-family regulator, ToxT. We have solved the 1.9 {angstrom} resolution crystal structure of ToxT, which reveals folds in the N- and C-terminal domains that share a number of features in common with AraC, MarA, and Rob as well as the unexpected presence of a buried 16-carbon fatty acid, cis-palmitoleate. The finding that cis-palmitoleic acid reduces TCP and CT expression in V. cholerae and prevents ToxT from binding to DNA in vitro provides a direct link between the host environment of V. cholerae and regulation of virulence gene expression.

  17. CPAG: software for leveraging pleiotropy in GWAS to reveal similarity between human traits links plasma fatty acids and intestinal inflammation.

    Wang, Liuyang; Oehlers, Stefan H; Espenschied, Scott T; Rawls, John F; Tobin, David M; Ko, Dennis C

    2015-01-01

    Meta-analyses of genome-wide association studies (GWAS) have demonstrated that the same genetic variants can be associated with multiple diseases and other complex traits. We present software called CPAG (Cross-Phenotype Analysis of GWAS) to look for similarities between 700 traits, build trees with informative clusters, and highlight underlying pathways. Clusters are consistent with pre-defined groups and literature-based validation but also reveal novel connections. We report similarity between plasma palmitoleic acid and Crohn's disease and find that specific fatty acids exacerbate enterocolitis in zebrafish. CPAG will become increasingly powerful as more genetic variants are uncovered, leading to a deeper understanding of complex traits. CPAG is freely available at www.sourceforge.net/projects/CPAG/. PMID:26374098

  18. The hydrological balance of a groundwater discharge fen

    Boeye, D.; Verheyen, R. F.

    1992-08-01

    Linear regression analysis and weekly water level measurements were used to study the hydrological balance of a groundwater discharge fen. The main water flows pertain to rainfall, evapotranspiration, and groundwater discharge. Owing to the high water table in depressions, rainfall is transformed partly to direct runoff. This process depends on the landform of the study area and on the daily distribution of rainfall and evapotranspiration. During very dry summers, evaporation causes a drop in the water table. Such events may be important for plant life in the fen. Protection of the regional groundwater flow and regulation of the ditches are potential measures for hydrological management of the site.

  19. Untangling the Effect of Fatty Acid Addition at Species Level Revealed Different Transcriptional Responses of the Biogas Microbial Community Members

    Treu, Laura; Campanaro, Stefano; Kougias, Panagiotis;

    2016-01-01

    In the present study, RNA-sequencing was used to elucidate the change of anaerobic digestion metatranscriptome after long chain fatty acids (oleate) exposure. To explore the general transcriptional behavior of the microbiome, the analysis was first performed on shotgun reads without considering...... a reference metagenome. As a second step, RNA reads were aligned on the genes encoded by the microbial community, revealing the expression of more than 51 000 different transcripts. The present study is the first research which was able to dissect the transcriptional behavior at a single species level...

  20. Stable isotope tracer reveals that viviparous snakes transport amino acids to offspring during gestation.

    Van Dyke, James U; Beaupre, Steven J

    2012-03-01

    Viviparity and placentation have evolved from oviparity over 100 times in squamate reptiles (lizards and snakes). The independent origins of placentation have resulted in a variety of placental morphologies in different taxa, ranging from simple apposition of fetal and maternal tissues to endotheliochorial implantation that is homoplasious with mammalian placentation. Because the eggs of oviparous squamates transport gases and water from the environment and calcium from the eggshell, the placentae of viviparous squamates are thought to have initially evolved to accomplish these functions from within the maternal oviduct. Species with complex placentae have also been shown to rely substantially, or even primarily, on placental transport of organic nutrients for embryonic nutrition. However, it is unclear whether species with only simple placentae are also capable of transporting organic nutrients to offspring. Among viviparous squamates, all of the snakes that have been studied thus far have been shown to have simple placentae. However, most studies of snake placentation are limited to a single lineage, the North American Natricinae. We tested the abilities of four species of viviparous snakes - Agkistrodon contortrix (Viperidae), Boa constrictor (Boidae), Nerodia sipedon (Colubridae: Natricinae) and Thamnophis sirtalis (Colubridae: Natricinae) - to transport diet-derived amino acids to offspring during gestation. We fed [(15)N]leucine to pregnant snakes, and compared offspring (15)N content with that of unlabeled controls. Labeled females allocated significantly more (15)N to offspring than did controls, but (15)N allocation did not differ among species. Our results indicate that viviparous snakes are capable of transporting diet-derived amino acids to their offspring during gestation, possibly via placentation. PMID:22323198

  1. Comparative Transcriptome Analysis Reveals the Influence of Abscisic Acid on the Metabolism of Pigments, Ascorbic Acid and Folic Acid during Strawberry Fruit Ripening.

    Dongdong Li

    Full Text Available A comprehensive investigation of abscisic acid (ABA biosynthesis and its influence on other important phytochemicals is critical for understanding the versatile roles that ABA plays during strawberry fruit ripening. Using RNA-seq technology, we sampled strawberry fruit in response to ABA or nordihydroguaiaretic acid (NDGA; an ABA biosynthesis blocker treatment during ripening and assessed the expression changes of genes involved in the metabolism of pigments, ascorbic acid (AsA and folic acid in the receptacles. The transcriptome analysis identified a lot of genes differentially expressed in response to ABA or NDGA treatment. In particular, genes in the anthocyanin biosynthesis pathway were actively regulated by ABA, with the exception of the gene encoding cinnamate 4-hydroxylase. Chlorophyll degradation was accelerated by ABA mainly owing to the higher expression of gene encoding pheide a oxygenase. The decrease of β-carotene content was accelerated by ABA treatment and delayed by NDGA. A high negative correlation rate was found between ABA and β-carotene content, indicating the importance of the requirement for ABA synthesis during fruit ripening. In addition, evaluation on the folate biosynthetic pathway indicate that ABA might have minor function in this nutrient's biosynthesis process, however, it might be involved in its homeostasis. Surprisingly, though AsA content accumulated during fruit ripening, expressions of genes involved in its biosynthesis in the receptacles were significantly lower in ABA-treated fruits. This transcriptome analysis expands our understanding of ABA's role in phytochemical metabolism during strawberry fruit ripening and the regulatory mechanisms of ABA on these pathways were discussed. Our study provides a wealth of genetic information in the metabolism pathways and may be helpful for molecular manipulation in the future.

  2. Transcriptomic analysis reveals the metabolic mechanism of L-ascorbic acid in Ziziphus jujuba Mill.

    Chunmei eZhang

    2016-02-01

    Full Text Available Chinese jujube (Ziziphus jujuba Mill. is the most economically important member of the Rhamnaceae family and contains a high concentration of ascorbic acid (AsA. To explore the metabolic mechanism of AsA accumulation, we investigated the abundance of AsA in the fruit development stages, the leaf and flower of Z. jujuba cv Junzao, and the mature fruit of one type of wild jujube (Z. jujuba var. spinosa Hu, Yanchuan sour jujube. And the expression patterns of genes involved in AsA biosynthesis, degradation and recycling were analyzed. The result showed that AsA biosynthesis during early fruit development (the enlargement stage is the main reason for jujube high accumulation. The L-galactose pathway plays a predominant role in the biosynthesis of AsA during jujube fruit development, and the genes GMP1, GME1, GGP, and GaLDH involved in the determination of AsA concentration during fruit development and in different genotypes; the myo-inositol pathway along with the genes GME2 and GMP2 in the L-galactose pathway play a compensatory role in maintaining AsA accumulation during the ripening stage. These findings enhance our understanding of the molecular mechanism in regulating AsA accumulation for jujube.

  3. Competing mechanisms for perfluoroalkyl acid accumulation in plants revealed using an Arabidopsis model system.

    Müller, Claudia E; LeFevre, Gregory H; Timofte, Anca E; Hussain, Fatima A; Sattely, Elizabeth S; Luthy, Richard G

    2016-05-01

    Perfluoroalkyl acids (PFAAs) bioaccumulate in plants, presenting a human exposure route if present in irrigation water. Curiously, accumulation of PFAAs in plant tissues is greatest for both the short-chain and long-chain PFAAs, generating a U-shaped relationship with chain length. In the present study, the authors decouple competing mechanisms of PFAA accumulation using a hydroponic model plant system (Arabidopsis thaliana) exposed to a suite of 10 PFAAs to determine uptake, depuration, and translocation kinetics. Rapid saturation of root concentrations occurred for all PFAAs except perfluorobutanoate, the least-sorptive (shortest-chain) PFAA. Shoot concentrations increased continuously, indicating that PFAAs are efficiently transported and accumulate in shoots. Tissue concentrations of PFAAs during depuration rapidly declined in roots but remained constant in shoots, demonstrating irreversibility of the translocation process. Root and shoot concentration factors followed the U-shaped trend with perfluoroalkyl chain length; however, when normalized to dead-tissue sorption, this relationship linearized. The authors therefore introduce a novel term, the "sorption normalized concentration factor," to describe PFAA accumulation in plants; because of their hydrophobicity, sorption is the determining factor for long-chain PFAAs, whereas the shortest-chain PFAAs are most effectively transported in the plant. The present study provides a mechanistic explanation for previously unexplained PFAA accumulation trends in plants and suggests that shorter-chained PFAAs may bioaccumulate more readily in edible portions. Environ Toxicol Chem 2016;35:1138-1147. © 2015 SETAC. PMID:26383989

  4. Anotaciones spbre algunos fenómenos del sistema nervioso

    Llinás, Pablo A.

    2011-01-01

    Con todo respeto y por su apreciado conducto, me permito solicitar de la docta corporación que usted dignamente preside, su valioso concepto sobre algunas anotaciones relativas a la fisiología y a la fisiopatología de ciertos fenómenos del sistema nervioso.

  5. Biogeographic patterns of base-rich fen vegetation across Europe

    Jiménez-Alfaro, B.; Hájek, Michal; Ejrnaes, R.; Rodwell, J.; Pawlikowski, P.; Weeda, E. J.; Laitinen, J.; Moen, A.; Bergamini, A.; Aunina, L.; Sekulová, L.; Tahvanainen, T.; Gillet, F.; Jandt, U.; Dítě, D.; Hájková, Petra; Corriol, G.; Kondelin, H.; Díaz, T. E.

    2014-01-01

    Roč. 17, č. 2 (2014), s. 367-380. ISSN 1402-2001 R&D Projects: GA ČR GAP505/10/0638 Institutional support: RVO:67985939 Keywords : rich fens * vegetation classification * climate Subject RIV: EF - Botanics Impact factor: 2.548, year: 2014

  6. Preliminary palaeomagnetic results from the Fen carbonatite complex, S. Norway

    Poorter, R.P.E.

    1972-01-01

    Samples from a hematite carbonate rock of the Eocambrian-Lower Cambrian Fen carbonatite-alkaline rock complex in southern Norway, yield a stable NRM with a direction after magnetic cleaning of D = 205°, I = −56° (N = 19, (k = 138, α95 = 3°). This corresponds with a palaeomagnetic pole position at 63

  7. From groundwater abstraction to vegetative response in fen ecosystems

    Johansen, Ole Munch; Jensen, Jacob Birk; Pedersen, Morten Lauge

    2014-01-01

    hydrology. Fens are rare and threatened worldwide due to pressures from agriculture, to lack of appropriate management and to altered catchment hydrology. A solid foundation for hydrological modelling was established based on intensive monitoring at the site, combined with full-scale pumping tests in the...

  8. Intramolecular allosteric communication in dopamine D2 receptor revealed by evolutionary amino acid covariation.

    Sung, Yun-Min; Wilkins, Angela D; Rodriguez, Gustavo J; Wensel, Theodore G; Lichtarge, Olivier

    2016-03-29

    The structural basis of allosteric signaling in G protein-coupled receptors (GPCRs) is important in guiding design of therapeutics and understanding phenotypic consequences of genetic variation. The Evolutionary Trace (ET) algorithm previously proved effective in redesigning receptors to mimic the ligand specificities of functionally distinct homologs. We now expand ET to consider mutual information, with validation in GPCR structure and dopamine D2 receptor (D2R) function. The new algorithm, called ET-MIp, identifies evolutionarily relevant patterns of amino acid covariations. The improved predictions of structural proximity and D2R mutagenesis demonstrate that ET-MIp predicts functional interactions between residue pairs, particularly potency and efficacy of activation by dopamine. Remarkably, although most of the residue pairs chosen for mutagenesis are neither in the binding pocket nor in contact with each other, many exhibited functional interactions, implying at-a-distance coupling. The functional interaction between the coupled pairs correlated best with the evolutionary coupling potential derived from dopamine receptor sequences rather than with broader sets of GPCR sequences. These data suggest that the allosteric communication responsible for dopamine responses is resolved by ET-MIp and best discerned within a short evolutionary distance. Most double mutants restored dopamine response to wild-type levels, also suggesting that tight regulation of the response to dopamine drove the coevolution and intramolecular communications between coupled residues. Our approach provides a general tool to identify evolutionary covariation patterns in small sets of close sequence homologs and to translate them into functional linkages between residues. PMID:26979958

  9. Lipidomics analysis reveals efficient storage of hepatic triacylglycerides enriched in unsaturated fatty acids after one bout of exercise in mice.

    Chunxiu Hu

    Full Text Available BACKGROUND: Endurance exercise induces lipolysis, increases circulating concentrations of free fatty acids (FFA and the uptake and oxidation of fatty acids in the working muscle. Less is known about the regulation of lipid metabolism in the liver during and post-exercise. METHODOLOGY/PRINCIPAL FINDINGS: We performed an ultra fast liquid chromatography-mass spectrometry (UFLC-MS based lipidomics analysis of liver tissue samples obtained from C57Bl/6J mice immediately after a 60 min treadmill run of moderate intensity, and after 3 h of recovery. The PLS-DA scores plot for 115 quantified lipid molecular species revealed a clear separation of the hepatic lipid profile of sedentary from recovering mice, but not from mice immediately after running. 21 lipid species were considered to be most responsible for the difference in the hepatic lipid profiles, including 17 triacylglycerides (TG, one lysophosphatidylcholine (LPC and three phosphatidylcholines (PC. TG species were found to be more abundant in the recovery phase, while PC species were decreased. The degree of accumulation of individual TG species correlated well with the amount of theoretical energy stored whereas no increase was found for TG species containing only saturated or one monounsaturated fatty acid. Total liver TG content as assayed by an enzymatic method was increased to 163% in the recovery phase, while it was significantly decreased in skeletal muscle by the exercise bout and remained less in the recovery phase. Results from fasted and refed mice indicate that fasting-induced lipolysis was associated with a pronounced accumulation of hepatic TG, which is reversed by refeeding for 5 h. Thus food intake per se did not elevate hepatic TG. CONCLUSION: These data indicate that high availability of FFA induced by endurance exercise or fasting resulted in a transient hepatic TG accumulation, while muscle TG content was decreased during exercise presumably due to increased muscle fatty

  10. Down-regulation of the caffeic acid O-methyltransferase gene in switchgrass reveals a novel monolignol analog

    Tschaplinski Timothy J

    2012-09-01

    Full Text Available Abstract Background Down-regulation of the caffeic acid 3-O-methyltransferase EC 2.1.1.68 (COMT gene in the lignin biosynthetic pathway of switchgrass (Panicum virgatum resulted in cell walls of transgenic plants releasing more constituent sugars after pretreatment by dilute acid and treatment with glycosyl hydrolases from an added enzyme preparation and from Clostridium thermocellum. Fermentation of both wild-type and transgenic switchgrass after milder hot water pretreatment with no water washing showed that only the transgenic switchgrass inhibited C. thermocellum. Gas chromatography–mass spectrometry (GCMS-based metabolomics were undertaken on cell wall aqueous extracts to determine the nature of the microbial inhibitors. Results GCMS confirmed the increased concentration of a number of phenolic acids and aldehydes that are known inhibitors of microbial fermentation. Metabolomic analyses of the transgenic biomass additionally revealed the presence of a novel monolignol-like metabolite, identified as trans-3, 4-dimethoxy-5-hydroxycinnamyl alcohol (iso-sinapyl alcohol in both non-pretreated, as well as hot water pretreated samples. iso-Sinapyl alcohol and its glucoside were subsequently generated by organic synthesis and the identity of natural and synthetic materials were confirmed by mass spectrometric and NMR analyses. The additional novel presence of iso-sinapic acid, iso-sinapyl aldehyde, and iso-syringin suggest the increased activity of a para-methyltransferase, concomitant with the reduced COMT activity, a strict meta-methyltransferase. Quantum chemical calculations were used to predict the most likely homodimeric lignans generated from dehydration reactions, but these products were not evident in plant samples. Conclusions Down-regulation of COMT activity in switchgrass resulted in the accumulation of previously undetected metabolites resembling sinapyl alcohol and its related metabolites, but that are derived from para

  11. Impacts of short-term droughts and inundations in species-rich fens during summer and winter: Large-scale field manipulation experiments

    C. Cusell; I.S. Mettrop; E.E. van Loon; L.P.M. Lamers; M. Vorenhout; A.M. Kooijman

    2015-01-01

    For the conservation and restoration of biodiverse rich fens, base-rich and nutrient-poor conditions are vital. In wetlands with artificially stable surface water levels, the re-introduction of temporary water level fluctuations has been postulated to restore the acid neutralizing capacity (ANC) of

  12. Quantitative proteomics analysis reveals glutamine deprivation activates fatty acid β-oxidation pathway in HepG2 cells.

    Long, Baisheng; Muhamad, Rodiallah; Yan, Guokai; Yu, Jie; Fan, Qiwen; Wang, Zhichang; Li, Xiuzhi; Purnomoadi, Agung; Achmadi, Joelal; Yan, Xianghua

    2016-05-01

    Glutamine, a multifunctional amino acid, functions in nutrient metabolism, energy balance, apoptosis, and cell proliferation. Lipid is an important nutrient and controls a broad range of physiological processes. Previous studies have demonstrated that glutamine can affect lipolysis and lipogenesis, but the effect of glutamine on the detailed lipid metabolism remains incompletely understood. Here, we applied the quantitative proteomics approach to estimate the relative abundance of proteins in HepG2 cells treated by glutamine deprivation. The results showed that there were 212 differentially abundant proteins in response to glutamine deprivation, including 150 significantly increased proteins and 62 significantly decreased proteins. Interestingly, functional classification showed that 43 differentially abundant proteins were related to lipid metabolism. Further bioinformatics analysis and western blotting validation revealed that lipid accumulation may be affected by β-oxidation of fatty acid induced by glutamine deprivation in HepG2 cells. Together, our results may provide the potential for regulating lipid metabolism by glutamine in animal production and human nutrition. The MS data have been deposited to the ProteomeXchange Consortium with identifier PXD003387. PMID:26837383

  13. Comparative Proteomic Analysis Reveals the Effects of Exogenous Calcium against Acid Rain Stress in Liquidambar formosana Hance Leaves.

    Hu, Wen-Jun; Wu, Qian; Liu, Xiang; Shen, Zhi-Jun; Chen, Juan; Liu, Ting-Wu; Chen, Juan; Zhu, Chun-Quan; Wu, Fei-Hua; Chen, Lin; Wei, Jia; Qiu, Xiao-Yun; Shen, Guo-Xin; Zheng, Hai-Lei

    2016-01-01

    Acid rain (AR) impacts forest health by leaching calcium (Ca) away from soils and plants. Ca is an essential element and participates in various plant physiological responses. In the present study, the protective role of exogenous Ca in alleviating AR stress in Liquidambar formosana Hance at the physiological and proteomic levels was examined. Our results showed that low Ca condition resulted in the chlorophyll content and photosynthesis decreasing significantly in L. formosana leaves; however, these effects could be reversed by high Ca supplementation. Further proteomic analyses successfully identified 81 differentially expressed proteins in AR-treated L. formosana under different Ca levels. In particular, some of the proteins are involved in primary metabolism, photosynthesis, energy production, antioxidant defense, transcription, and translation. Moreover, quantitative real time polymerase chain reaction (qRT-PCR) results indicated that low Ca significantly increased the expression level of the investigated Ca-related genes, which can be reversed by high Ca supplementation under AR stress. Further, Western blotting analysis revealed that exogenous Ca supply reduced AR damage by elevating the expression of proteins involved in the Calvin cycle, reactive oxygen species (ROS) scavenging system. These findings allowed us to better understand how woody plants respond to AR stress at various Ca levels and the protective role of exogenous Ca against AR stress in forest tree species. PMID:26616104

  14. In Vivo Screening Using Transgenic Zebrafish Embryos Reveals New Effects of HDAC Inhibitors Trichostatin A and Valproic Acid on Organogenesis.

    Ling Li

    Full Text Available The effects of endocrine disrupting chemicals (EDCs on reproduction are well known, whereas their developmental effects are much less characterized. However, exposure to endocrine disruptors during organogenesis may lead to deleterious and permanent problems later in life. Zebrafish (Danio rerio transgenic lines expressing the green fluorescent protein (GFP in specific organs and tissues are powerful tools to uncover developmental defects elicited by EDCs. Here, we used seven transgenic lines to visualize in vivo whether a series of EDCs and other pharmaceutical compounds can alter organogenesis in zebrafish. We used transgenic lines expressing GFP in pancreas, liver, blood vessels, inner ear, nervous system, pharyngeal tooth and pectoral fins. This screen revealed that four of the tested chemicals have detectable effects on different organs, which shows that the range of effects elicited by EDCs is wider than anticipated. The endocrine disruptor tetrabromobisphenol-A (TBBPA, as well as the three drugs diclofenac, trichostatin A (TSA and valproic acid (VPA induced abnormalities in the embryonic vascular system of zebrafish. Moreover, TSA and VPA induced specific alterations during the development of pancreas, an observation that was confirmed by in situ hybridization with specific markers. Developmental delays were also induced by TSA and VPA in the liver and in pharyngeal teeth, resulting in smaller organ size. Our results show that EDCs can induce a large range of developmental alterations during embryogenesis of zebrafish and establish GFP transgenic lines as powerful tools to screen for EDCs effects in vivo.

  15. In Vivo Screening Using Transgenic Zebrafish Embryos Reveals New Effects of HDAC Inhibitors Trichostatin A and Valproic Acid on Organogenesis.

    Li, Ling; Bonneton, François; Tohme, Marie; Bernard, Laure; Chen, Xiao Yong; Laudet, Vincent

    2016-01-01

    The effects of endocrine disrupting chemicals (EDCs) on reproduction are well known, whereas their developmental effects are much less characterized. However, exposure to endocrine disruptors during organogenesis may lead to deleterious and permanent problems later in life. Zebrafish (Danio rerio) transgenic lines expressing the green fluorescent protein (GFP) in specific organs and tissues are powerful tools to uncover developmental defects elicited by EDCs. Here, we used seven transgenic lines to visualize in vivo whether a series of EDCs and other pharmaceutical compounds can alter organogenesis in zebrafish. We used transgenic lines expressing GFP in pancreas, liver, blood vessels, inner ear, nervous system, pharyngeal tooth and pectoral fins. This screen revealed that four of the tested chemicals have detectable effects on different organs, which shows that the range of effects elicited by EDCs is wider than anticipated. The endocrine disruptor tetrabromobisphenol-A (TBBPA), as well as the three drugs diclofenac, trichostatin A (TSA) and valproic acid (VPA) induced abnormalities in the embryonic vascular system of zebrafish. Moreover, TSA and VPA induced specific alterations during the development of pancreas, an observation that was confirmed by in situ hybridization with specific markers. Developmental delays were also induced by TSA and VPA in the liver and in pharyngeal teeth, resulting in smaller organ size. Our results show that EDCs can induce a large range of developmental alterations during embryogenesis of zebrafish and establish GFP transgenic lines as powerful tools to screen for EDCs effects in vivo. PMID:26900852

  16. Sulfur and carbon isotope biogeochemistry of a rewetted brackish fen

    Koebsch, Franziska; Gehre, Matthias; Winkel, Matthias; Koehler, Stefan; Koch, Marian; Jurasinski, Gerald; Spitzy, Alejandro; Liebner, Susanne; Sachs, Torsten; Schmiedinger, Iris; Kretzschmann, Lisett; Saborowski, Anke; Böttcher, Michael E.

    2015-04-01

    Coastal wetlands are at the interface between terrestrial freshwater and marine and exhibit very specific biogeochemical conditions. Intermittent sea water intrusion affects metabolic pathways, i. e. anaerobic carbon metabolism is progressively dominated by sulfate reduction with lower contribution of methanogenesis whilst methane production is increasingly shifted from acetoclastic to hydrogenotrophic. Due to expanding anthropogenic impact a large proportion of coastal ecosystems is degraded with severe implications for the biogeochemical processes. We use concentration patterns and stable isotope signatures of water, sulfate, dissolved carbonate, and methane (δ2H, δ13C, δ18O, δ34S) to investigate the S and C metabolic cycle in a rewetted fen close to the southern Baltic Sea border. Such studies are crucial to better predict dynamic ecosystem feedback to global change like organic matter (OM) decomposition or greenhouse gas emissions. Yet, little is known about the metabolic pathways in such environments. The study site is part of the TERENO Observatory "Northeastern German Lowlands' and measurements of methane emissions have run since 2009. High methane fluxes up to 800 mg m-2 hr-1 indicate that methanogenesis is the dominant C metabolism pathway despite of high sulfate concentrations (up to 37 mM). The presented data are part of a comprehensive biogeochemical investigation that we conducted in autumn 2014 and that comprises 4 pore water profiles and sediment samples within a transect of 300-1500 m distance to the Baltic Sea. Depth of organic layers ranged from 25 to 140 cm with high OM contents (up to 90 dwt.%). Sulfate/chloride ratios in the pore waters were lower than in the Baltic Sea for most sites and sediment depths indicated a substantial net sulfate loss. Sulfide concentrations were negligible at the top and increased parallel to the sulfate concentrations with depth to values of up to 0.3 mM. One pore water profiles situated 1150 m from the Baltic

  17. Understanding the Groundwater Hydrology of a Geographically-Isolated Prairie Fen: Implications for Conservation.

    Prasanna Venkatesh Sampath

    Full Text Available The sources of water and corresponding delivery mechanisms to groundwater-fed fens are not well understood due to the multi-scale geo-morphologic variability of the glacial landscape in which they occur. This lack of understanding limits the ability to effectively conserve these systems and the ecosystem services they provide, including biodiversity and water provisioning. While fens tend to occur in clusters around regional groundwater mounds, Ives Road Fen in southern Michigan is an example of a geographically-isolated fen. In this paper, we apply a multi-scale groundwater modeling approach to understand the groundwater sources for Ives Road fen. We apply Transition Probability geo-statistics on more than 3000 well logs from a state-wide water well database to characterize the complex geology using conditional simulations. We subsequently implement a 3-dimensional reverse particle tracking to delineate groundwater contribution areas to the fen. The fen receives water from multiple sources: local recharge, regional recharge from an extensive till plain, a regional groundwater mound, and a nearby pond. The regional sources deliver water through a tortuous, 3-dimensional "pipeline" consisting of a confined aquifer lying beneath an extensive clay layer. Water in this pipeline reaches the fen by upwelling through openings in the clay layer. The pipeline connects the geographically-isolated fen to the same regional mound that provides water to other fen clusters in southern Michigan. The major implication of these findings is that fen conservation efforts must be expanded from focusing on individual fens and their immediate surroundings, to studying the much larger and inter-connected hydrologic network that sustains multiple fens.

  18. Understanding the Groundwater Hydrology of a Geographically-Isolated Prairie Fen: Implications for Conservation.

    Sampath, Prasanna Venkatesh; Liao, Hua-Sheng; Curtis, Zachary Kristopher; Doran, Patrick J; Herbert, Matthew E; May, Christopher A; Li, Shu-Guang

    2015-01-01

    The sources of water and corresponding delivery mechanisms to groundwater-fed fens are not well understood due to the multi-scale geo-morphologic variability of the glacial landscape in which they occur. This lack of understanding limits the ability to effectively conserve these systems and the ecosystem services they provide, including biodiversity and water provisioning. While fens tend to occur in clusters around regional groundwater mounds, Ives Road Fen in southern Michigan is an example of a geographically-isolated fen. In this paper, we apply a multi-scale groundwater modeling approach to understand the groundwater sources for Ives Road fen. We apply Transition Probability geo-statistics on more than 3000 well logs from a state-wide water well database to characterize the complex geology using conditional simulations. We subsequently implement a 3-dimensional reverse particle tracking to delineate groundwater contribution areas to the fen. The fen receives water from multiple sources: local recharge, regional recharge from an extensive till plain, a regional groundwater mound, and a nearby pond. The regional sources deliver water through a tortuous, 3-dimensional "pipeline" consisting of a confined aquifer lying beneath an extensive clay layer. Water in this pipeline reaches the fen by upwelling through openings in the clay layer. The pipeline connects the geographically-isolated fen to the same regional mound that provides water to other fen clusters in southern Michigan. The major implication of these findings is that fen conservation efforts must be expanded from focusing on individual fens and their immediate surroundings, to studying the much larger and inter-connected hydrologic network that sustains multiple fens. PMID:26452279

  19. Stable isotope studies reveal pathways for the incorporation of non-essential amino acids in Acyrthosiphon pisum (pea aphids).

    Haribal, Meena; Jander, Georg

    2015-12-01

    Plant roots incorporate inorganic nitrogen into the amino acids glutamine, glutamic acid, asparagine and aspartic acid, which together serve as the primary metabolites of nitrogen transport to other tissues. Given the preponderance of these four amino acids, phloem sap is a nutritionally unbalanced diet for phloem-feeding insects. Therefore, aphids and other phloem feeders typically rely on microbial symbionts for the synthesis of essential amino acids. To investigate the metabolism of the four main transport amino acids by the pea aphid (Acyrthosiphon pisum), and its Buchnera aphidicola endosymbionts, aphids were fed defined diets with stable isotope-labeled glutamine, glutamic acid, asparagine or aspartic acid (U-(13)C, U-(15)N; U-(15)N; α-(15)N; or γ-(15)N). The metabolic fate of the dietary (15)N and (13)C was traced using gas chromatography-mass spectrometry (GC-MS). Nitrogen was the major contributor to the observed amino acid isotopomers with one additional unit mass (M+1). However, there was differential incorporation, with the amine nitrogen of asparagine being incorporated into other amino acids more efficiently than the amide nitrogen. Higher isotopomers (M+2, M+3 and M+4) indicated the incorporation of varying numbers of (13)C atoms into essential amino acids. GC-MS assays also showed that, even with an excess of dietary labeled glutamine, glutamic acid, asparagine or aspartic acid, the overall content of these amino acids in aphid bodies was mostly the product of catabolism of dietary amino acids and subsequent re-synthesis within the aphids. Thus, these predominant dietary amino acids are not passed directly to Buchnera endosymbionts for synthesis of essential amino acids, but are rather are produced de novo, most likely by endogenous aphid enzymes. PMID:26632455

  20. Partitioning of soil CO2 efflux in un-manipulated and experimentally flooded plots of a temperate fen

    W. Borken

    2012-05-01

    Full Text Available Peatlands store large amounts of organic carbon, but the carbon stock is sensitive to changes in precipitation or water table manipulations. Restoration of drained peatlands by drain blocking and flooding is a common measure to conserve and augment the carbon stock of peatland soils. Here, we report to what extent flooding affected the contribution of heterotrophic and rhizosphere respiration to soil CO2 efflux in a grass-dominated mountain fen, Germany. Soil CO2 efflux was measured in three un-manipulated control plots and three flooded plots in two consecutive years. Flooding was achieved by permanent irrigation during the growing seasons. Radiocarbon signatures of CO2 from different sources including soil CO2 efflux, incubated peat cores and live grass roots were repeatedly analyzed for partitioning of soil CO2 efflux. Additionally, heterotrophic respiration and its radiocarbon signature were determined by eliminating rhizosphere respiration in trenched subplots (only control. In the control plots, rhizosphere respiration determined by 14C signatures contributed between 47 and 61% during the growing season, but was small (4% immediately before budding. Trenching revealed a smaller rhizosphere contribution of 33% (2009 and 22% (2010 during growing seasons. Flooding reduced annual soil CO2 efflux of the fen by 42% in 2009 and by 30% in 2010. The reduction was smaller in 2010 mainly through naturally elevated water level in the control plots. A 1-week interruption of irrigation caused a strong short-lived increase in soil CO2 efflux, demonstrating the sensitivity of the fen to water table drawdown near the peat surface. The reduction in soil CO2 efflux in the flooded plots diminished the relative proportion of rhizosphere respiration from 56 to 46%, suggesting that rhizosphere respiration was slightly more sensitive to flooding than heterotrophic respiration. We conclude that the moderate decrease in rhizosphere respiration following flooding

  1. Fenómenos de transporte : un curso introductorio

    Betancourt Grajales, Ramiro

    1991-01-01

    Fenómenos de transporte, es el nombre colectivo que se da al estudio sistemático e integrado de tres áreas clásicas de la ciencia de la Ingeniería : 1) Transporte de Energía o Calor, 2) Transporte de Masa o Difusión, y 3) Transporte de Cantidad de Movimiento o Impulso (Momentum en Inglés), o Dinámica de Fluidos. Debido a que con frecuencia el transporte de masa y de calor ocurren en un fluido, algunos planes de estudio incluyen estos procesos en su tratamiento de la mecánica de fluidos....

  2. Fenótipos clínicos de asma grave Clinical phenotypes of severe asthma

    Roseliane de Souza Araújo Alves

    2008-09-01

    Full Text Available OBJETIVO: Estabelecer os fenótipos clínicos em portadores de asma grave. MÉTODOS: Foram estudados, retrospectivamente, 111 pacientes em um ambulatório especializado. Os pacientes foram avaliados e acompanhados de maneira sistemática, estabelecendo-se ao final do acompanhamento a adesão e o controle ou não da doença por dados clínicos e funcionais. A resistência ao tratamento foi definida como o não preenchimento, ao final do acompanhamento, por pelo menos seis meses, dos critérios de controle de asma, apesar do uso correto e adesão à medicação. Os fenótipos foram determinados por análise fatorial e comparados por testes diversos. RESULTADOS: Ao final, 88 pacientes foram considerados aderentes e 23 não aderentes. Por análise fatorial do grupo aderente, quatro fenótipos foram determinados: o fenótipo 1 (28 pacientes, formado pelos pacientes resistentes ao tratamento, com maior freqüência de sintomas noturnos, maior número de exacerbações e uso mais freqüente de broncodilatador de resgate; o fenótipo 2 (48 pacientes, formado pelos pacientes com obstrução persistente, com menores valores de relação volume expiratório forçado no primeiro segundo/capacidade vital forçada na avaliação inicial, idade mais avançada e maior tempo de doença; o fenótipo 3 (42 pacientes, representa os pacientes com rinossinusite alérgica, sendo constituído de não fumantes com obstrução predominantemente reversível; e o fenótipo 4 (15 pacientes, formado por casos com história de intolerância à aspirina associado à asma quase fatal. CONCLUSÕES: Um número significativo de portadores de ama grave não adere ao tratamento. Muitos pacientes com asma grave têm obstrução irreversível, mas o fenótipo clínico mais relevante é constituído pelos pacientes resistentes ao tratamento habitual.OBJECTIVE: To characterize clinical phenotypes of severe asthma. METHODS: A total of 111 patients were retrospectively evaluated at a

  3. A Causal Network Analysis of the Fatty Acid Metabolome in African-Americans Reveals a Critical Role for Palmitoleate and Margarate

    Yazdani, Akram; Boerwinkle, Eric

    2016-01-01

    Abstract Fatty acids are important sources of energy and possible predictors and etiologic factors in many common complex pathologies such as cardiovascular disease, diabetes, and certain forms of cancers. While fatty acids are thought to covary with each other, their underlying causal networks have not been fully elucidated. This study reports the identification and analysis of a statistical causal network among 15 mostly long-chain fatty acids. In an African-American population sample and using the Genome granularity-Directed Acyclic Graph (GDAG) algorithm, we determined directions or causal relationships in the fatty acid metabolome. A directed causal network was constructed that revealed 29 significant edges among the 15 nodes (p < 0.001). We report that two fatty acid metabolites, palmitoleate and margarate, which originate from dietary intake, together influence every other fatty acid in the network. On the other hand, despite its high connectivity, dihomo-linoleate did not appear to play an important role over the whole fatty acid network. These findings collectively suggest possible strategic entry points for new treatments or preventive modalities against diseases affected by fatty acid metabolites such as cardiovascular disease, diabetes, and obesity. Further studies examining the embedded substructure of the fatty acid metabolite networks in independent population samples would be timely and warranted as we move toward novel postgenomic diagnostics and therapeutics. PMID:27501297

  4. Landform design for a fen wetland on a tailings sand deposit in northern Alberta

    McKenna, G.T.; Papini, A.G.; Scordo, E.B. [BGC Engineering Inc., Vancouver, BC (Canada); Wytrykush, C. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    2010-07-01

    This paper discussed one of the first fens to be established in a post-mining area of the Athabasca oil sands region. The entire watershed is specifically designed to support a wetland, and it will be constructed on a soft tailings deposit. A fen is a peat-accumulating wetland with a water table that is at, or close to, the surface consisting of mineral-saturated water coming from either groundwater or surface water. In order to monitor and adjust the fen design for field conditions, a full hydrological site investigation was launched together with parallel research programs involving the creation of a conservative landform design with controls over surface water and groundwater seepage inputs. Controlling the salinity of fen waters from tailings consolidation and seepage over time is a critical component to fen design. There are a limited number of documented examples of large-scale constructed fen wetlands.

  5. Understanding toxicity at the watershed scale : design of the Syncrude Sandhill Fen watershed research project

    Fens are peat-accumulating wetlands with a water table consisting of mineral-rich ground or surface water. This study discussed the construction of a fen-type reclaimed wetland constructed in a post-mining oil sands landscape. Syncrude Canada's Sandhill fen watershed project represents the first attempt at constructing a fen wetland in the oil sands region. The wetland and its watershed will be constructed on a soft tailings deposit. The design basis for the fen and watershed was developed by a team of researchers and scientists. The aim of the fen design was to control the salinity caused by tailings consolidation and seepage over time. Methods of mitigating potentially toxic effects from salinity were discussed.

  6. Elemental microchemistry, fatty acid profile and geometric morphometrics signatures of goose barnacles (Pollicipes pollicipes reveal their place of origin

    Rui Albuquerque

    2014-06-01

    Full Text Available Seafood plays an important role in the socioeconomic, gastronomy and cultural heritage of Portuguese coastal communities. In the Iberian Peninsula, the goose barnacle Pollicipes pollicipes is the intertidal biological resource most heavily exploited by man, resulting on overexploitation of stocks. In the MPA of BNR P.pollicipes harvesting is however strictly regulated, making it a good example of marine resources management. Analytical methods able to identify the origin of goose barnacle would be an important tool to help the management of the trade. For such purpose, we investigated whether P. pollicipes have site-specific differences based on its elemental microchemistry (EM, fatty acid profile (FA and capitulum shape (CS. The analysis was performed on specimens collected from 3 sites in the BNR and 7 along a 300 km stretch of the Portuguese coast. For each individual we analysed the largest lateral shell for EM using ICP-MS, the FA content of the muscle using GC-FID, and the CS using geometric morphometrics. Discriminant function analyses (DFA for both EM and FA separately provided a high reclassification success (77.6% and 99% respectively, of cross-validated cases correctly classified, while for EM combined with FA allowed for a 100% reclassification success. DFA analysis based only on CS, revealed a low classification success (29.6%. These results show that EM and FA signatures can be a powerful tool to infer goose barnacles origin. Such “fingerprinting” approach can be used to track and identify goose barnacles origin, helping in establishing an origin certificate and increasing the potential value of biological resources from Portuguese MPAs.

  7. Impact of grazing on vegetation and on selected plant species of calcareous fens

    Stammel, Barbara

    2005-01-01

    Calcareous fens are traditionally mown in autumn, which maintains species rich vegetation types (Caricion davallianae, Molinion caeruleae). Nowadays, abandonment due to changes in agriculture causes a decline of many characteristic plant species of fen meadows due to litter accumulation and dominance of few competitive species. The aim of this study is to evaluate grazing as an alternative management tool to mowing. The impact of grazing and mowing on the vegetation of calcareous fens in the ...

  8. Understanding the Groundwater Hydrology of a Geographically-Isolated Prairie Fen: Implications for Conservation

    Sampath, Prasanna Venkatesh; Liao, Hua-Sheng; Curtis, Zachary Kristopher; Patrick J Doran; Matthew E Herbert; May, Christopher A.; Li, Shu-Guang

    2015-01-01

    The sources of water and corresponding delivery mechanisms to groundwater-fed fens are not well understood due to the multi-scale geo-morphologic variability of the glacial landscape in which they occur. This lack of understanding limits the ability to effectively conserve these systems and the ecosystem services they provide, including biodiversity and water provisioning. While fens tend to occur in clusters around regional groundwater mounds, Ives Road Fen in southern Michigan is an example...

  9. Fenómeno de Koebner The Koebner phenomenon

    R E Achenbach

    2011-09-01

    Full Text Available Descrito en 1871 por Heinrich Koebner, su fenómeno es uno de los más conocidos en la Dermatología. Koebner lo describe en un paciente con psoriasis que sufrió escoriaciones múltiples y una mordedura de caballo. Su figura fue una de las más destacadas en la Dermatología del siglo 19. Se revisa la lista de entidades con fenómeno Koebner y sus variantes, los tipos de injurias y su patogenia.First described in 1871, the Koebner phenomenon is one of the most well-known entities in dermatology. Heinrich Koebner is credited with the first adequate description of this peculiar disposition of psoriatic skin. He was one of the outstanding dermatologists of the 19th Century and reported the formation of psoriasiform lesions in uninvolved skin after excoriations and horse bites. Types of Koebner response, a list of injuries capable to produce it and a review of the pathogenesis are reviewed.

  10. Seed longevity and germination characteristics of six fen plant species.

    Tatár, S

    2010-01-01

    Fens are among the most threatened habitats in Europe as their area has decreased considerably in the last centuries. For successful management and restoration conservationists need detailed knowledge about seed bank formation and seed longevity of plants, as these features are closely related to successional and vegetation dynamical processes. I analysed seed longevity and the germination characteristics of six fen plant species by seed burial experiments. Based on seed weight, seed bank was expected for long-term persistent for the light-seeded Schoenus nigricans, Carex appropinquata, C. pseudocyperus, C. davalliana and Peucedanum palustre and also that for the medium-seeded Cicuta virosa. It was proved that, the latter two species have short-term persistent seed banks, while Carex pseudocyperus has a transient seed bank, therefore these species may only have a limited role in restoration from seed banks. It was found that Schoenus nigricans, Carex appropinquata and C. davalliana have persistent seed banks, because some of their four-year-old seeds have emerged. Fresh seeds had low germination rate in all studied species and majority of seeds emerged after winter, except for Carex pseudocyperus. After the germination peak in spring, the majority of the ungerminated seeds of Schoenus nigricans, Peucedanum palustre, Carex appropinquata, C. davalliana and Cicuta virosa entered a secondary dormancy phase that was broken in autumn. I found the seasonal emergence of the latter three species highly similar. PMID:21565777

  11. Effects of elevated CO2 on fen peat biogeochemistry

    Effects of elevated atmospheric CO2 concentration on northern peatland biogeochemistry was studied in a short-term experiment. Eight intact soil cores (11-cm diameter x -cm depth) with Juncus and Festuca spp. were collected from a calcareous fen in north Wales. Half of the cores were incubated under 350 ppm CO2 concentration, whilst the other four cores were maintained at 700 ppm CO2. After a 4-month incubation, significantly higher biomass (root+shoot+algal mat) was determined under elevated CO2 conditions. Higher emissions of N2O and CO2, and higher concentration of pore-water DOC (dissolved organic carbon) were also observed under elevated CO2. However, no significant differences were found in CH4 emission or soil enzyme activities (β-glucosidase, phosphatase, and N-acetylglucosaminidase) in the bulk soil. Overall, the results suggest that elevated CO2 would increase the primary productivity of the fen vegetation, and stimulate N2O and CO2 emissions as a consequence of an enhanced DOC supply from the vegetation to the soil microbes

  12. Pseudomonas lini Strain ZBG1 Revealed Carboxylic Acid Utilization and Copper Resistance Features Required for Adaptation to Vineyard Soil Environment: A Draft Genome Analysis

    Chan, Kok-Gan; Chong, Teik-Min; Adrian, Tan-Guan-Sheng; Kher, Heng Leong; Grandclément, Catherine; Faure, Denis; Yin, Wai-Fong; Dessaux, Yves; Hong, Kar-Wai

    2016-01-01

    Pseudomonas lini strain ZBG1 was isolated from the soil of vineyard in Zellenberg, France and the draft genome was reported in this study. Bioinformatics analyses of the genome revealed presence of genes encoding tartaric and malic acid utilization as well as copper resistance that correspond to the adaptation this strain in vineyard soil environment. PMID:27512520

  13. Key plant species and succession patterns associated to past fen-bog transitions - perspective to future

    Väliranta, Minna; Luoto, Miska; Juutinen, Sari; Korhola, Atte; Tuittila, Eeva-stiina

    2016-04-01

    Minerotrophic fens and ombrotrophic bogs differ in their hydrology, vegetation and carbon dynamics and their geographical distribution seems to be linked to certain climate parameters, such as temperature and effective precipitation. Currently bogs dominate the southern boreal zone but the climate warming with altered temperature and effective precipitation may shift the distribution of bog zone northwards. In this study, we first used plant macrofossil method and radiocarbon analysis to identify and date past fen-bog transitions. These transitions were compared to major Holocene climate phases. Subsequently, palaeoecological data were associated to ecological and environmental data collected along the current fen-bog ecotone in Finland. We identified three successional phases 1) initial minerotrophic fen phase 2) Eriophorum vaginatum-dominated oligotrophic fen phase which was followed by 3) ombrorophic bog phase. Duration of these phases varied but late Holocene timing of fen-bog transition showed some consistency. Based on palaeoecological data 57 % of the modern ecotone peatlands were classified to be in a fen phase, 10 % were in an Eriophorum-dominated phase and 33 % were going through a transition from fen to bog. The study showed that regime shifts are driven by autogenic succession and climate but also fires may efficiently control succession pathways. Our results support the hypothesis that climate change can promote the ombrotrophication process in the southern border of the fen-bog ecotone due to changes in hydrology balance.

  14. O fenómeno do futebol em Portugal : estudo de caso Concelho da Guarda

    Neves, Armando Jorge Gonçalves de Almeida

    2013-01-01

    O futebol é, na actualidade, um dos fenómenos sociais mais importantes da sociedade portuguesa, que tem a capacidade de produzir diversos outros fenómenos, mobilizar públicos e suscitar angústias. Os aspectos culturais, económicos, sociais e políticos constroem a sua pludimensionalidade, com repercussão no território, que é preciso delimitar. Assim, sendo o futebol, considerado neste trabalho, um fenómeno social total, é também um fenómeno local. Estudar o futebol numa determin...

  15. Denitrification activity of a remarkably diverse fen denitrifier community in finnish lapland is N-oxide limited.

    Palmer, Katharina; Horn, Marcus A

    2015-01-01

    Peatlands cover more than 30% of the Finnish land area and impact N2O fluxes. Denitrifiers release N2O as an intermediate or end product. In situ N2O emissions of a near pH neutral pristine fen soil in Finnish Lapland were marginal during gas chamber measurements. However, nitrate and ammonium fertilization significantly stimulated in situ N2O emissions. Stimulation with nitrate was stronger than with ammonium. N2O was produced and subsequently consumed in gas chambers. In unsupplemented anoxic microcosms, fen soil produced N2O only when acetylene was added to block nitrous oxide reductase, suggesting complete denitrification. Nitrate and nitrite stimulated denitrification in fen soil, and maximal reaction velocities (vmax) of nitrate or nitrite dependent denitrification where 18 and 52 nmol N2O h-1 gDW-1, respectively. N2O was below 30% of total produced N gases in fen soil when concentrations of nitrate and nitrite were N2O consumption was up to 36 nmol N2O h-1 gDW-1. Denitrifier diversity was assessed by analyses of narG, nirK/nirS, and nosZ (encoding nitrate-, nitrite-, and nitrous oxide reductases, respectively) by barcoded amplicon pyrosequencing. Analyses of ~14,000 quality filtered sequences indicated up to 25 species-level operational taxonomic units (OTUs), and up to 359 OTUs at 97% sequence similarity, suggesting diverse denitrifiers. Phylogenetic analyses revealed clusters distantly related to publicly available sequences, suggesting hitherto unknown denitrifiers. Representatives of species-level OTUs were affiliated with sequences of unknown soil bacteria and Actinobacterial, Alpha-, Beta-, Gamma-, and Delta-Proteobacterial sequences. Comparison of the 4 gene markers at 97% similarity indicated a higher diversity of narG than for the other gene markers based on Shannon indices and observed number of OTUs. The collective data indicate (i) a high denitrification and N2O consumption potential, and (ii) a highly diverse, nitrate limited denitrifier

  16. Denitrification activity of a remarkably diverse fen denitrifier community in finnish lapland is N-oxide limited.

    Katharina Palmer

    Full Text Available Peatlands cover more than 30% of the Finnish land area and impact N2O fluxes. Denitrifiers release N2O as an intermediate or end product. In situ N2O emissions of a near pH neutral pristine fen soil in Finnish Lapland were marginal during gas chamber measurements. However, nitrate and ammonium fertilization significantly stimulated in situ N2O emissions. Stimulation with nitrate was stronger than with ammonium. N2O was produced and subsequently consumed in gas chambers. In unsupplemented anoxic microcosms, fen soil produced N2O only when acetylene was added to block nitrous oxide reductase, suggesting complete denitrification. Nitrate and nitrite stimulated denitrification in fen soil, and maximal reaction velocities (vmax of nitrate or nitrite dependent denitrification where 18 and 52 nmol N2O h-1 gDW-1, respectively. N2O was below 30% of total produced N gases in fen soil when concentrations of nitrate and nitrite were <500 μM. vmax for N2O consumption was up to 36 nmol N2O h-1 gDW-1. Denitrifier diversity was assessed by analyses of narG, nirK/nirS, and nosZ (encoding nitrate-, nitrite-, and nitrous oxide reductases, respectively by barcoded amplicon pyrosequencing. Analyses of ~14,000 quality filtered sequences indicated up to 25 species-level operational taxonomic units (OTUs, and up to 359 OTUs at 97% sequence similarity, suggesting diverse denitrifiers. Phylogenetic analyses revealed clusters distantly related to publicly available sequences, suggesting hitherto unknown denitrifiers. Representatives of species-level OTUs were affiliated with sequences of unknown soil bacteria and Actinobacterial, Alpha-, Beta-, Gamma-, and Delta-Proteobacterial sequences. Comparison of the 4 gene markers at 97% similarity indicated a higher diversity of narG than for the other gene markers based on Shannon indices and observed number of OTUs. The collective data indicate (i a high denitrification and N2O consumption potential, and (ii a highly diverse

  17. Fenómenos de interfase en sistemas coloidales

    Bregni, Carlos; Serrao, Rosa

    1988-01-01

    Uno de los aspectos más importantes en la formulación de dispersiones de aplicación farmacéutica, es el conocimiento de aquellas propiedades fisicoquímicas, que involucran fenómenos de superficie e interfase en sistemas de naturaleza coloidal. La medida de conductividad específica y de viscosidad aparente en función de la concentración de electrolitos presentes en el medio permitió determinar la concentración crítica en la que se logra la saturación de la superficie de la partícula coloidal d...

  18. Throughflow as a determining factor for habitat contiguity in a near-natural fen

    Loon, A.H. van; Schot, P.P.; Griffioen, J.; Bierkens, M.F.P.; Batelaan, O.; Wassen, M.J.

    2009-01-01

    Knowledge of the hydrological mechanisms that underlie stable plant communities within natural fens is essential for the improvement of current fen restoration and conservation strategies. In this study, steady-state groundwater modelling was performed to quantify the impact of throughflow mechanism

  19. Nutrient imitations in an extant and drained poor fen : implications for restoration

    VanDuren, IC; Boeye, D; Grootjans, AP

    1997-01-01

    In a species-rich poor fen (Caricetum nigrae) and a species-poor drained fen, the difference in nutrient limitation of the vegetation was assessed in a full-factorial fertilization experiment with N, P and K. The results were compared to the nutrient ratios of plant material and to chemical analysis

  20. Remotely sensed hydrological isolation : A key factor predicting plant species distribution in fens

    Sanders, M.E.

    1999-01-01

    In fens the species composition, vegetation structure and succession rate are determined by vegetation management and water chemistry, particularly by the base status and nutrient status. Base-rich and nutrient-rich surface water causes fens to become eutrophied, which leads to an increased biomass

  1. Serum metabolomics reveals higher levels of polyunsaturated fatty acids in lepromatous leprosy: potential markers for susceptibility and pathogenesis.

    Reem Al-Mubarak

    2011-09-01

    Full Text Available BACKGROUND: Leprosy is a disease of the skin and peripheral nervous system caused by the obligate intracellular bacterium Mycobacterium leprae. The clinical presentations of leprosy are spectral, with the severity of disease determined by the balance between the cellular and humoral immune response of the host. The exact mechanisms that facilitate disease susceptibility, onset and progression to certain clinical phenotypes are presently unclear. Various studies have examined lipid metabolism in leprosy, but there has been limited work using whole metabolite profiles to distinguish the clinical forms of leprosy. METHODOLOGY AND PRINCIPAL FINDINGS: In this study we adopted a metabolomics approach using high mass accuracy ultrahigh pressure liquid chromatography mass spectrometry (UPLC-MS to investigate the circulatory biomarkers in newly diagnosed untreated leprosy patients. Sera from patients having bacterial indices (BI below 1 or above 4 were selected, subjected to UPLC-MS, and then analyzed for biomarkers which distinguish the polar presentations of leprosy. We found significant increases in the abundance of certain polyunsaturated fatty acids (PUFAs and phospholipids in the high-BI patients, when contrasted with the levels in the low-BI patients. In particular, the median values of arachidonic acid (2-fold increase, eicosapentaenoic acid (2.6-fold increase and docosahexaenoic acid (1.6-fold increase were found to be greater in the high-BI patients. SIGNIFICANCE: Eicosapentaenoic acid and docosahexaenoic acid are known to exert anti-inflammatory properties, while arachidonic acid has been reported to have both pro- and anti-inflammatory activities. The observed increase in the levels of several lipids in high-BI patients may provide novel clues regarding the biological pathways involved in the immunomodulation of leprosy. Furthermore, these results may lead to the discovery of biomarkers that can be used to investigate susceptibility to

  2. Hepatitis B virus X protein (HBx)-induced abnormalities of nucleic acid metabolism revealed by 1H-NMR-based metabonomics

    Dan Yue; Zhang, Yuwei; Cheng, Liuliu; Ma, Jinhu; Xi, Yufeng; Yang, Liping; Su, Chao; Shao, Bin; Huang, Anliang; Xiang, Rong; Cheng, Ping

    2016-01-01

    Hepatitis B virus X protein (HBx) plays an important role in HBV-related hepatocarcinogenesis; however, mechanisms underlying HBx-mediated carcinogenesis remain unclear. In this study, an NMR-based metabolomics approach was applied to systematically investigate the effects of HBx on cell metabolism. EdU incorporation assay was conducted to examine the effects of HBx on DNA synthesis, an important feature of nucleic acid metabolism. The results revealed that HBx disrupted metabolism of glucose, lipids, and amino acids, especially nucleic acids. To understand the potential mechanism of HBx-induced abnormalities of nucleic acid metabolism, gene expression profiles of HepG2 cells expressing HBx were investigated. The results showed that 29 genes involved in DNA damage and DNA repair were differentially expressed in HBx-expressing HepG2 cells. HBx-induced DNA damage was further demonstrated by karyotyping, comet assay, Western blotting, immunofluorescence and immunohistochemistry analyses. Many studies have previously reported that DNA damage can induce abnormalities of nucleic acid metabolism. Thus, our results implied that HBx initially induces DNA damage, and then disrupts nucleic acid metabolism, which in turn blocks DNA repair and induces the occurrence of hepatocellular carcinoma (HCC). These findings further contribute to our understanding of the occurrence of HCC. PMID:27075403

  3. Proteomic analysis of mitochondria reveals a metabolic switch from fatty acid oxidation to glycolysis in the failing heart

    2009-01-01

    This work characterizes the mitochondrial proteomic profile in the failing heart and elucidates the molecular basis of mitochondria in heart failure. Heart failure was induced in rats by myocardial infarction, and mitochondria were isolated from hearts by differential centrifugation. Using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry, a system biology approach was employed to investigate differences in mitochondrial proteins between normal and failing hearts. Mass spectrometry identified 27 proteins differentially expressed that involved in energy metabolism. Among those, the up-regulated proteins included tricarboxylic acid cycle enzymes and pyruvate dehydrogenase complex subunits while the down-regulated proteins were involved in fatty acid oxidation and the OXPHOS complex. These results suggest a substantial metabolic switch from free fatty acid oxidation to glycolysis in heart failure and provide molecular evidence for alterations in the structural and functional parameters of mitochondria that may contribute to cardiac dysfunction during ischemic injury.

  4. Factors affecting the interactions between beta-lactoglobulin and fatty acids as revealed in molecular dynamics simulations.

    Yi, Changhong; Wambo, Thierry O

    2015-09-21

    Beta-lactoglobulin (BLG), a bovine dairy protein, is a promiscuously interacting protein that can bind multiple hydrophobic ligands. Fatty acids (FAs), common hydrophobic molecules bound to BLG, are important sources of fuel for life because they yield large quantities of ATP when metabolized. The binding affinity increases with the length of the ligands, indicating the importance of the van der Waals (vdW) interactions between the hydrocarbon tail and the hydrophobic calyx of BLG. An exception to this rule is caprylic acid (OCA) which is two-carbon shorter but has a stronger binding affinity than capric acid. Theoretical calculations in the current literature are not accurate enough to shed light on the underlying physics of this exception. The computed affinity values are greater for longer fatty acids without respect for the caprylic exception and those values are generally several orders of magnitude away from the experimental data. In this work, we used hybrid steered molecular dynamics to accurately compute the binding free energies between BLG and the five saturated FAs of 8 to 16 carbon atoms. The computed binding free energies agree well with experimental data not only in rank but also in absolute values. We gained insights into the exceptional behavior of caprylic acid in the computed values of entropy and electrostatic interactions. We found that the electrostatic interaction between the carboxyl group of caprylic acid and the two amino groups of K60/69 in BLG is much stronger than the vdW force between the OCA's hydrophobic tail and the BLG calyx. This pulls OCA to the top of the beta barrel where it is easier to fluctuate, giving rise to greater entropy of OCA at the binding site. PMID:26272099

  5. Fatty acids and small organic compounds bind to mineralo-organic nanoparticles derived from human body fluids as revealed by metabolomic analysis

    Martel, Jan; Wu, Cheng-Yeu; Hung, Cheng-Yu; Wong, Tsui-Yin; Cheng, Ann-Joy; Cheng, Mei-Ling; Shiao, Ming-Shi; Young, John D.

    2016-03-01

    Nanoparticles entering the human body instantly become coated with a ``protein corona'' that influences the effects and distribution of the particles in vivo. Yet, whether nanoparticles may bind to other organic compounds remains unclear. Here we use an untargeted metabolomic approach based on ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry to identify the organic compounds that bind to mineral nanoparticles formed in human body fluids (serum, plasma, saliva, and urine). A wide range of organic compounds is identified, including fatty acids, glycerophospholipids, amino acids, sugars, and amides. Our results reveal that, in addition to the proteins identified previously, nanoparticles harbor an ``organic corona'' containing several fatty acids which may affect particle-cell interactions in vivo. This study provides a platform to study the organic corona of biological and synthetic nanoparticles found in the human body.Nanoparticles entering the human body instantly become coated with a ``protein corona'' that influences the effects and distribution of the particles in vivo. Yet, whether nanoparticles may bind to other organic compounds remains unclear. Here we use an untargeted metabolomic approach based on ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry to identify the organic compounds that bind to mineral nanoparticles formed in human body fluids (serum, plasma, saliva, and urine). A wide range of organic compounds is identified, including fatty acids, glycerophospholipids, amino acids, sugars, and amides. Our results reveal that, in addition to the proteins identified previously, nanoparticles harbor an ``organic corona'' containing several fatty acids which may affect particle-cell interactions in vivo. This study provides a platform to study the organic corona of biological and synthetic nanoparticles found in the human body. Electronic supplementary information (ESI) available. See

  6. Screening of lactic acid bacteria from Indonesia reveals glucansucrase and fructansucrase genes in two different Weissella confusa strains from soya

    Malik, Amarila; Radji, Maksum; Kralj, Slavko; Dijkhuizen, Lubbert

    2009-01-01

    Homopolysaccharide (glucan and fructan) synthesis from sucrose by sucrase enzymes in lactic acid bacteria (LAB) has been well studied in the genera Leuconostoc, Streptococcus and Lactobacillus. This study aimed to identify and characterize genes encoding glucansucrase/glucosyltransferase (GTF) and f

  7. Knockout studies reveal an important role of Plasmodium lipoic acid protein ligase A1 for asexual blood stage parasite survival.

    Svenja Günther

    Full Text Available Lipoic acid (LA is a dithiol-containing cofactor that is essential for the function of alpha-keto acid dehydrogenase complexes. LA acts as a reversible acyl group acceptor and 'swinging arm' during acyl-coenzyme A formation. The cofactor is post-translationally attached to the acyl-transferase subunits of the multienzyme complexes through the action of octanoyl (lipoyl: N-octanoyl (lipoyl transferase (LipB or lipoic acid protein ligases (LplA. Remarkably, apicomplexan parasites possess LA biosynthesis as well as scavenging pathways and the two pathways are distributed between mitochondrion and a vestigial organelle, the apicoplast. The apicoplast-specific LipB is dispensable for parasite growth due to functional redundancy of the parasite's lipoic acid/octanoic acid ligases/transferases. In this study, we show that LplA1 plays a pivotal role during the development of the erythrocytic stages of the malaria parasite. Gene disruptions in the human malaria parasite P. falciparum consistently were unsuccessful while in the rodent malaria model parasite P. berghei the LplA1 gene locus was targeted by knock-in and knockout constructs. However, the LplA1((- mutant could not be cloned suggesting a critical role of LplA1 for asexual parasite growth in vitro and in vivo. These experimental genetics data suggest that lipoylation during expansion in red blood cells largely occurs through salvage from the host erythrocytes and subsequent ligation of LA to the target proteins of the malaria parasite.

  8. Effects of Perfluorooctanoic Acid on Metabolic Profiles in Brain and Liver of Mouse Revealed by a High-throughput Targeted Metabolomics Approach

    Yu, Nanyang; Wei, Si; Li, Meiying; Yang, Jingping; Li, Kan; Jin, Ling; Xie, Yuwei; Giesy, John P.; Zhang, Xiaowei; Yu, Hongxia

    2016-04-01

    Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, can result in hepatotoxicity and neurobehavioral effects in animals. The metabolome, which serves as a connection among transcriptome, proteome and toxic effects, provides pathway-based insights into effects of PFOA. Since understanding of changes in the metabolic profile during hepatotoxicity and neurotoxicity were still incomplete, a high-throughput targeted metabolomics approach (278 metabolites) was used to investigate effects of exposure to PFOA for 28 d on brain and liver of male Balb/c mice. Results of multivariate statistical analysis indicated that PFOA caused alterations in metabolic pathways in exposed individuals. Pathway analysis suggested that PFOA affected metabolism of amino acids, lipids, carbohydrates and energetics. Ten and 18 metabolites were identified as potential unique biomarkers of exposure to PFOA in brain and liver, respectively. In brain, PFOA affected concentrations of neurotransmitters, including serotonin, dopamine, norepinephrine, and glutamate in brain, which provides novel insights into mechanisms of PFOA-induced neurobehavioral effects. In liver, profiles of lipids revealed involvement of β-oxidation and biosynthesis of saturated and unsaturated fatty acids in PFOA-induced hepatotoxicity, while alterations in metabolism of arachidonic acid suggesting potential of PFOA to cause inflammation response in liver. These results provide insight into the mechanism and biomarkers for PFOA-induced effects.

  9. Effects of Perfluorooctanoic Acid on Metabolic Profiles in Brain and Liver of Mouse Revealed by a High-throughput Targeted Metabolomics Approach

    Yu, Nanyang; Wei, Si; Li, Meiying; Yang, Jingping; Li, Kan; Jin, Ling; Xie, Yuwei; Giesy, John P.; Zhang, Xiaowei; Yu, Hongxia

    2016-01-01

    Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, can result in hepatotoxicity and neurobehavioral effects in animals. The metabolome, which serves as a connection among transcriptome, proteome and toxic effects, provides pathway-based insights into effects of PFOA. Since understanding of changes in the metabolic profile during hepatotoxicity and neurotoxicity were still incomplete, a high-throughput targeted metabolomics approach (278 metabolites) was used to investigate effects of exposure to PFOA for 28 d on brain and liver of male Balb/c mice. Results of multivariate statistical analysis indicated that PFOA caused alterations in metabolic pathways in exposed individuals. Pathway analysis suggested that PFOA affected metabolism of amino acids, lipids, carbohydrates and energetics. Ten and 18 metabolites were identified as potential unique biomarkers of exposure to PFOA in brain and liver, respectively. In brain, PFOA affected concentrations of neurotransmitters, including serotonin, dopamine, norepinephrine, and glutamate in brain, which provides novel insights into mechanisms of PFOA-induced neurobehavioral effects. In liver, profiles of lipids revealed involvement of β-oxidation and biosynthesis of saturated and unsaturated fatty acids in PFOA-induced hepatotoxicity, while alterations in metabolism of arachidonic acid suggesting potential of PFOA to cause inflammation response in liver. These results provide insight into the mechanism and biomarkers for PFOA-induced effects. PMID:27032815

  10. Facile fabrication of FeN nanoparticles/nitrogen-doped graphene core-shell hybrid and its use as a platform for NADH detection in human blood serum.

    Balamurugan, Jayaraman; Thanh, Tran Duy; Kim, Nam Hoon; Lee, Joong Hee

    2016-09-15

    Herein, we present a novel strategy for the synthesis of an iron nitride nanoparticles-encapsulated nitrogen-doped graphene (FeN NPs/NG) core-shell hierarchical nanostructure to boost the electrochemical performance in a highly sensitive, selective, reproducible, and stable sensing platform for nicotinamide adenine dinucleotide (NADH). This core-shell hierarchical nanostructure provides an excellent conductive network for effective charge transfer and avoids the agglomeration and restacking of NG sheets, which provides better access to the electrode material for NADH oxidation. The FeN NPs/NG core-shell hierarchical nanostructure demonstrates direct and mediatorless responses to NADH oxidation at a low potential. This material displays a high sensitivity of 0.028μA/μMcm(2), a wide linear range from 0.4 to 718μM, and a detection limit of 25nM with a fast response time of less than 3s. The interferences from common interferents, such as glucose, uric acid, dopamine, and ascorbic acid, are negligible. The fabricated sensor was further tested for the determination of NADH in human blood serum. The resulting high sensitivity, excellent selectivity, outstanding stability, and good reproducibility make the proposed FeN NPs/NG core-shell hierarchical nanostructure as a promising candidate for biomedical applications. PMID:27104586

  11. Expression and characterization of manganese lipoxygenase of the rice blast fungus reveals prominent sequential lipoxygenation of α-linolenic acid.

    Wennman, Anneli; Jernerén, Fredrik; Magnuson, Ann; Oliw, Ernst H

    2015-10-01

    Magnaporthe oryzae causes rice blast disease and has become a model organism of fungal infections. M. oryzae can oxygenate fatty acids by 7,8-linoleate diol synthase, 10R-dioxygenase-epoxy alcohol synthase, and by a putative manganese lipoxygenase (Mo-MnLOX). The latter two are transcribed during infection. The open reading frame of Mo-MnLOX was deduced from genome and cDNA analysis. Recombinant Mo-MnLOX was expressed in Pichia pastoris and purified to homogeneity. The enzyme contained protein-bound Mn and oxidized 18:2n-6 and 18:3n-3 to 9S-, 11-, and 13R-hydroperoxy metabolites by suprafacial hydrogen abstraction and oxygenation. The 11-hydroperoxides were subject to β-fragmentation with formation of 9S- and 13R-hydroperoxy fatty acids. Oxygen consumption indicated apparent kcat values of 2.8 s(-1) (18:2n-6) and 3.9 s(-1) (18:3n-3), and UV analysis yielded apparent Km values of 8 and 12 μM, respectively, for biosynthesis of cis-trans conjugated metabolites. 9S-Hydroperoxy-10E,12Z,15Z-octadecatrienoic acid was rapidly further oxidized to a triene, 9S,16S-dihydroperoxy-10E,12Z,14E-octadecatrienoic acid. In conclusion, we have expressed, purified and characterized a new MnLOX from M. oryzae. The pathogen likely secretes Mo-MnLOX and phospholipases to generate oxylipins and to oxidize lipid membranes of rice cells and the cuticle. PMID:26264916

  12. Proteomic analysis of mitochondria reveals a metabolic switch from fatty acid oxidation to glycolysis in the failing heart

    WANG Jun; WANG TingZhong; LIU Ping; FAN FenLing; GUAN YouFei; MA AiQun; BAI Ling; LI Jing; SUN ChaoFeng; ZHAO Jin; CUI ChangCong; HAN Ke; LIU Yu; ZHUO XiaoZhen

    2009-01-01

    This work characterizes the mitochondrial proteomic profile in the failing heart and elucidates the molecular basis of mitochondria in heart failure.Heart failure was induced in rats by myocardial infarction,and mitochondria were isolated from hearts by differential centrifugation.Using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry,a system biology approach was employed to investigate differences in mitochondrial proteins between normal and failing hearts.Mass spectrometry identified 27 proteins differentially expressed that involved in energy metabolism.Among those,the up-regulated proteins included tricarboxylic acid cycle enzymes and pyruvate dehydrogenase complex subunita while the down-regulated proteins were involved in fatty acid oxidation and the OXPHOS complex.These results suggest a substantial metabolic switch from free fatty acid oxidation to glycolysis in heart failure and provide molecular evidence for alterations in the structural and functional parameters of mitochondria that may contribute to cardiac dysfunction during ischemic injury.

  13. Mass Spectrometry Analysis Coupled with de novo Sequencing Reveals Amino Acid Substitutions in Nucleocapsid Protein from Influenza A Virus

    Zijian Li

    2014-02-01

    Full Text Available Amino acid substitutions in influenza A virus are the main reasons for both antigenic shift and virulence change, which result from non-synonymous mutations in the viral genome. Nucleocapsid protein (NP, one of the major structural proteins of influenza virus, is responsible for regulation of viral RNA synthesis and replication. In this report we used LC-MS/MS to analyze tryptic digestion of nucleocapsid protein of influenza virus (A/Puerto Rico/8/1934 H1N1, which was isolated and purified by SDS poly-acrylamide gel electrophoresis. Thus, LC-MS/MS analyses, coupled with manual de novo sequencing, allowed the determination of three substituted amino acid residues R452K, T423A and N430T in two tryptic peptides. The obtained results provided experimental evidence that amino acid substitutions resulted from non-synonymous gene mutations could be directly characterized by mass spectrometry in proteins of RNA viruses such as influenza A virus.

  14. BOREAS TE-1 SSA-Fen Soil Profile Nutrient Data

    Papagno, Andrea; Anderson, Darwin; Newcomer, Jeffrey A. (Editor); Hall, Forrest G. (Editor)

    2000-01-01

    The BOREAS TE-1 team collected various data to characterize the soil-plant systems in the BOREAS SSA. Particular emphasis was placed on nutrient biochemistry, the stores and transfers of organic carbon, and how the characteristics were related to measured methane fluxes. The overall traniect in the Prince Albert National Park (Saskatchewan, Canada) included the major plant communities and related soils that occurred in that section of the boreal forest. Soil physical, chemical, and biological measurements along the transect were used to characterize the static environment, which allowed them to be related to methane fluxes. Chamber techniques were used to provide a measure of methane production/uptake. Chamber measurements coupled with flask sampling were used to determine the seasonality of methane fluxes. This particular data set contains soil profile measurements of various nutrients at the SSA-Fen site. The data were collected from 23-May to 21-Oct- 1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  15. Fenýlketónúría (PKU)

    Eydís Eva Pálsdóttir 1989

    2014-01-01

    Eftirfarandi umfjöllun er 10 ECTS lokaverkefni til BA gráðu í þroskaþjálfafræði á Íþrótta-, tómstunda- og þroskaþjálfasviði Háskóla Íslands. Verkefnið er tvíþætt og inniheldur annars vegar bækling um meðfædda efnaskiptagallann fenýlketónúría (PKU) og hins vegar fræðilega greinargerð. Ákveðinn skortur er á íslensku efni um PKU og kom hugmynd að sérhönnuðum bæklingi til í ljósi þeirrar staðreyndar. Tilgangur bæklingsins er að veita einstaklingum með PKU, aðstandendum þeirra og hverjum þeim er m...

  16. Computerbasiert prüfen [Computer-based Assessment

    Frey, Peter

    2006-08-01

    Full Text Available [english] Computer-based testing in medical education offers new perspectives. Advantages are sequential or adaptive testing, integration of movies or sound, rapid feedback to candidates and management of web-based question banks. Computer-based testing can also be implemented in an OSCE examination. In e-learning environments formative self-assessment are often implemented and gives helpful feedbacks to learners. Disadvantages in high-stake exams are the high requirements as well for the quality of testing (e.g. standard setting as additionally for the information technology and especially for security. [german] Computerbasierte Prüfungen im Medizinstudium eröffnen neue Möglichkeiten. Vorteile solcher Prüfungen liegen im sequentiellen oder adaptiven Prüfen, in der Integration von Bewegtbildern oder Ton, der raschen Auswertung und zentraler Verwaltung der Prüfungsfragen via Internet. Ein Einsatzgebiet mit vertretbarem Aufwand sind Prüfungen mit mehreren Stationen wie beispielsweise die OSCE-Prüfung. Computerbasierte formative Selbsttests werden im Bereiche e-learning häufig angeboten. Das hilft den Lernenden ihren Wissensstand besser einzuschätzen oder sich mit den Leistungen anderer zu vergleichen. Grenzen zeigen sich bei den summativen Prüfungen beim Prüfungsort, da zuhause Betrug möglich ist. Höhere ärztliche Kompetenzen wie Untersuchungstechnik oder Kommunikation eigenen sich kaum für rechnergestützte Prüfungen.

  17. Volatile profiling reveals intracellular metabolic changes in Aspergillus parasiticus: veA regulates branched chain amino acid and ethanol metabolism

    Roze Ludmila V

    2010-08-01

    Full Text Available Abstract Background Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine; we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions 1 Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2 VeA coordinates the

  18. Changes in Colorado Subalpine Fen Peat Stratigraphy and Humification During the Holocene

    Sullivan, D. G.

    2013-12-01

    This project focuses on the record of peat stratigraphy and decomposition preserved in cores taken from minerotrophic peatlands in Colorado. Subalpine peatlands in the Colorado Rocky Mountains and in the Colorado Plateau cover only about 2% of the state's land area, yet these wetlands provide important wildlife habitat and ecosystem services. The peatlands in Colorado are fens, and, while summer precipitation contributes to the local hydrology, the fens are only found in locations where winter snowpack persists long enough into the summers to maintain sufficiently high water tables to preserve the peat. We hypothesized that changes in summer precipitation and winter snowpack through the Holocene would be evident in the degree of peat humification and stratigraphy. We were interested in determining how warmer summer conditions early in the Holocene influenced precipitation, particularly summer monsoons, and thus, groundwater. In addition, our research using lake sediment cores in the region indicates that sediment organic content may fluctuate with paleotemperature. We sought to determine whether fens likewise preserve evidence of relatively low magnitude temperature changes, including those associated with the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA). Since fens persist in the region only under marginal conditions, they are very sensitive to fluctuations in climate and consequent hydrological responses. Nine fens were sampled in the study. Fen stratigraphy was studied at all of the sites. Humification analysis and bulk density and organic content determinations were conducted at one-centimeter intervals on cores from four of the fens. Core chronology was established using radiocarbon dating. Our results suggest that warmer summers in the early Holocene led to earlier snowmelt at lower elevations. Fens located near the lower margins of the subalpine zone (<3100 m elevation) ceased to accumulate peat during this period, changing to alluvial

  19. Fenómenos complejos en sistemas extendidos en el espacio

    Sánchez de la Lama, Marta

    2009-01-01

    Uno de los aspectos más fascinantes del mundo que nos rodea es la gran variedad de escalas a las que tienen lugar los diversos fenómenos. En muchos casos esta diversidad pone de manifiesto la estructura fractal de la Naturaleza y podemos hablar entonces de fenómenos complejos, en los que eventos de diferentes magnitudes no pueden analizarse de manera independiente. Dicha complejidad emerge como un fenómeno cooperativo a escalas microscópicas, que produce un complejo comportamiento macroscópic...

  20. Fenómenos complejos en sistemas extendidos en el espacio

    Sánchez de la Lama, Marta

    2011-01-01

    RESUMEN: Uno de los aspectos más fascinantes del mundo que nos rodea es la gran variedad de escalas a las que tienen lugar los diversos fenómenos. En muchos casos esta diversidad pone de manifiesto la estructura fractal de la naturaleza y podemos hablar entonces de fenómenos complejos, en los que eventos de diferentes magnitudes no pueden analizarse de manera independiente. Dicha complejidad emerge como un fenómeno cooperativo a escalas microscópicas, que produce un complejo comportamient...

  1. Los compuestos fenólicos en la autodefensa de los vegetales

    Maestro-Durán, R.

    1993-12-01

    Full Text Available This article covers the studies on phytoalexins activity of phenolic compounds (cinnamic acids, flavonoids, isoflavonoids, deoxianthocyanins, stilbenes, coumarins, chromones against fungi and bacteria. The relationship between hydrophilic-lipophilic balance activity is reported. Finally some reports on the preparation of synthetic phytoalexins sharing structural similarities with the natural ones (stilbenes, epi-catechin derivatives, of commercial interest as pesticides, insecticides and fungicides, are revised.

    En este trabajo se recogen los estudios sobre la actividad como fitoalexinas (compuestos post-infeccionales cuya formación implica o desrrepresión de genes o activación de un sistema enzimático que no operaba antes de la infección, tanto frente a hongos como frente a bacterias, de compuestos de tipo fenólico (ácidos cinámicos, flavonoides, isoflavonoides, deoxiantocianinas, estilbenos, cumarinas, cromonas. Se señala la relación entre el balance hidrófilo-lipófilo y la actividad como fitoalexinas. Finalmente se recogen trabajos sobre la obtención de fitoalexinas sintéticas de estructuras similares a las naturales (estilbenos, derivados de epicatequinas de interés comercial como pesticidas, insecticidas o fungicidas.

  2. Response of anaerobic carbon cycling to water table manipulation in an Alaskan rich fen

    Kane, E.S.; Chivers, M.R.; Turetsky, M.R.; Treat, C.C.; Petersen, D.G.; Waldrop, M.; Harden, J.W.; McGuire, A.D.

    2013-01-01

    To test the effects of altered hydrology on organic soil decomposition, we investigated CO2 and CH4 production potential of rich-fen peat (mean surface pH = 6.3) collected from a field water table manipulation experiment including control, raised and lowered water table treatments. Mean anaerobic CO2 production potential at 10 cm depth (14.1 ± 0.9 μmol C g−1 d−1) was as high as aerobic CO2 production potential (10.6 ± 1.5 μmol C g−1 d−1), while CH4 production was low (mean of 7.8 ± 1.5 nmol C g−1 d−1). Denitrification enzyme activity indicated a very high denitrification potential (197 ± 23 μg N g−1 d−1), but net NO-3 reduction suggested this was a relatively minor pathway for anaerobic CO2 production. Abundances of denitrifier genes (nirK and nosZ) did not change across water table treatments. SO2-4 reduction also did not appear to be an important pathway for anaerobic CO2 production. The net accumulation of acetate and formate as decomposition end products in the raised water table treatment suggested that fermentation was a significant pathway for carbon mineralization, even in the presence of NO-3. Dissolved organic carbon (DOC) concentrations were the strongest predictors of potential anaerobic and aerobic CO2 production. Across all water table treatments, the CO2:CH4 ratio increased with initial DOC leachate concentrations. While the field water table treatment did not have a significant effect on mean CO2 or CH4 production potential, the CO2:CH4 ratio was highest in shallow peat incubations from the drained treatment. These data suggest that with continued drying or with a more variable water table, anaerobic CO2 production may be favored over CH4 production in this rich fen. Future research examining the potential for dissolved organic substances to facilitate anaerobic respiration, or alternative redox processes that limit the effectiveness of organic acids as substrates in anaerobic metabolism, would help explain additional

  3. Metabolomic Analysis Reveals Increased Aerobic Glycolysis and Amino Acid Deficit in a Cellular Model of Amyotrophic Lateral Sclerosis.

    Valbuena, Gabriel N; Rizzardini, Milena; Cimini, Sara; Siskos, Alexandros P; Bendotti, Caterina; Cantoni, Lavinia; Keun, Hector C

    2016-05-01

    Defects in energy metabolism are potential pathogenic mechanisms in amyotrophic lateral sclerosis (ALS), a rapidly fatal disease with no cure. The mechanisms through which this occurs remain elusive and their understanding may prove therapeutically useful. We used metabolomics and stable isotope tracers to examine metabolic changes in a well-characterized cell model of familial ALS, the motor neuronal NSC-34 line stably expressing human wild-type Cu/Zn superoxide dismutase (wtSOD1) or mutant G93A (G93ASOD1). Our findings indicate that wt and G93ASOD1 expression both enhanced glucose metabolism under serum deprivation. However, in wtSOD1 cells, this phenotype increased supply of amino acids for protein and glutathione synthesis, while in G93ASOD1 cells it was associated with death, aerobic glycolysis, and a broad dysregulation of amino acid homeostasis. Aerobic glycolysis was mainly due to induction of pyruvate dehydrogenase kinase 1. Our study thus provides novel insight into the role of deranged energy metabolism as a cause of poor adaptation to stress and a promoter of neural cell damage in the presence of mutant SOD1. Furthermore, the metabolic alterations we report may help explain why mitochondrial dysfunction and impairment of the endoplasmic reticulum stress response are frequently seen in ALS. PMID:25963727

  4. Assemblages of earthworms and collembolans in fen soil as affected by landslide

    Sterzyńska, M.; Nicia, P.; Pižl, Václav

    Coimbra : University of Coimbra, 2012. s. 30. [International Colloquium on Soil Zoology /16./. 06.08.2012-10.08.2012, Coimbra] Institutional support: RVO:60077344 Keywords : earthworms * collembolans * fen soil * landslide Subject RIV: EH - Ecology, Behaviour

  5. Understanding Prairie Fen Hydrology - a Hierarchical Multi-Scale Groundwater Modeling Approach

    Sampath, P.; Liao, H.; Abbas, H.; Ma, L.; Li, S.

    2012-12-01

    Prairie fens provide critical habitat to more than 50 rare species and significantly contribute to the biodiversity of the upper Great Lakes region. The sustainability of these globally unique ecosystems, however, requires that they be fed by a steady supply of pristine, calcareous groundwater. Understanding the hydrology that supports the existence of such fens is essential in preserving these valuable habitats. This research uses process-based multi-scale groundwater modeling for this purpose. Two fen-sites, MacCready Fen and Ives Road Fen, in Southern Michigan were systematically studied. A hierarchy of nested steady-state models was built for each fen-site to capture the system's dynamics at spatial scales ranging from the regional groundwater-shed to the local fens. The models utilize high-resolution Digital Elevation Models (DEM), National Hydrologic Datasets (NHD), a recently-assembled water-well database, and results from a state-wide groundwater mapping project to represent the complex hydro-geological and stress framework. The modeling system simulates both shallow glacial and deep bedrock aquifers as well as the interaction between surface water and groundwater. Aquifer heterogeneities were explicitly simulated with multi-scale transition probability geo-statistics. A two-way hydraulic head feedback mechanism was set up between the nested models, such that the parent models provided boundary conditions to the child models, and in turn the child models provided local information to the parent models. A hierarchical mass budget analysis was performed to estimate the seepage fluxes at the surface water/groundwater interfaces and to assess the relative importance of the processes at multiple scales that contribute water to the fens. The models were calibrated using observed base-flows at stream gauging stations and/or static water levels at wells. Three-dimensional particle tracking was used to predict the sources of water to the fens. We observed from the

  6. Late-Glacial and Holocene history of the Western Carpathian calcareous fens

    Hájková, Petra; Horsák, M.; Hájek, Michal

    Zeist: KNNV Publishing, 2012 - (Grootjans, A.; Šefferová-Stanová, V.; Jansen, A.), s. 13-20 ISBN 9789050114417 Institutional support: RVO:67985939 Keywords : macrofossils * snails * relict species * calcareous fens Subject RIV: EF - Botanics

  7. Stream characteristics and their implications for the protection of riparian fens and meadows

    Baattrup-Pedersen, A.; Larsen, S.E.; Andersen, Peter Mejlhede;

    2011-01-01

    1. Running waters, including associated riparian areas, are embraced by international legal frameworks outlining targets for the preservation, protection and improvement of the quality of the environment. Interactions between stream and river processes and riparian habitats have not received much...... riparian areas, affecting conditions needed to sustain protected fen and meadow communities. 4. We also found that water chemistry strongly influenced the occurrence of fen and meadow vegetation in riparian areas. The probability of finding fen and meadow vegetation was reduced when total phosphorus (TP...... influence of stream size, morphology and chemical water characteristics for the distribution of water-dependent terrestrial habitat types, i.e. alkaline fens, periodically inundated meadows and meadows in riparian areas in Denmark using an extensive data set covering a total of 254 stream reaches. A species...

  8. Atributos privativos e musicais do fenômeno noturno

    Clovis Salgado Gontijo Oliveira Clovis Salgado Gontijo Oliveira

    2015-11-01

    Full Text Available Desde a sua análise como mero fenômeno, elaborada com pretensões de neutralidade, a noite é por nós concebida a partir de atributos predominantemente privativos. Estes se acentuam culturalmente na tradição ocidental, que tende a desvalorizá-los como signos de um vazio de ordem ontológica, epistemológica, ética e, até mesmo, estética. Associadas a uma esfera de negatividade, tais privações parecem impedir ou, pelo menos, dificultar o tratamento artístico da experiência noturna, sobretudo quando este pretende se realizar num modelo de arte em continuidade com uma proposta visual e iluminista. Tomando como base nossa tese de doutorado, intitulada XXX, pretendemos aqui analisar de que modo os atributos privativos referentes à noite não só dificultam a sua mímese quanto estão presentes, sob nova interpretação, em contextos que revalorizam positivamente a experiência noturna, potencializando-a, assim, como motivo. Dentre estes contextos, concederemos particular atenção à arte musical, que, coincidentemente, manifesta para o teórico e o ouvinte alguns dos mesmos atributos privativos identificados na análise primária do noturno. A fim de efetuar este estudo, recorreremos ao pensamento de Vladimir Jankélévitch, principal fundamentação teórica da tese cujo percurso será sintetizado neste artigo.

  9. Arterial Tortuosity Syndrome reveals function of dehydroascorbic acid in collagen and elastin synthesis: Implications for skin care.

    Kitt, Douglas Q

    2016-02-01

    Some investigations in Arterial Tortuosity Syndrome (ATS) suggest that impaired intracellular transport of the oxidized form of vitamin C (dehydroascorbic acid, DHAA) is at the core of the pathogenesis. Lack of vitamin C for lysyl- and prolyl-hydroxylase activity may explain the defects in collagen and elastin formation found in ATS, and draws strong parallels between ATS and scurvy. Topically applied vitamin C has a well-established basis in the field of skin care, and part of its benefit is attributed to proper collagen formation in the skin. The ATS studies suggest that DHAA transport is necessary for normal skin collagen formation, and this has implications as to the forms of vitamin C best-suited for topical skin care. PMID:26826631

  10. Dissociative Ionization Mechanism and Appearance Energies in Adipic Acid Revealed by Imaging Photoelectron Photoion Coincidence, Selective Deuteration, and Calculations.

    Heringa, Maarten F; Slowik, Jay G; Prévôt, André S H; Baltensperger, Urs; Hemberger, Patrick; Bodi, Andras

    2016-05-26

    Adipic acid, a model compound for oxygenated organic aerosol, has been studied at the VUV beamline of the Swiss Light Source. Internal energy selected cations were prepared by threshold photoionization using vacuum ultraviolet synchrotron radiation and imaging photoelectron photoion coincidence spectroscopy (iPEPICO). The threshold photoelectron spectrum yields a vertical ionization energy (IE) of 10.5 eV, significantly above the calculated adiabatic IE of 8.6 eV. The cationic minimum is accessible after vertical ionization by H-transfer from one of the γ-carbons to a carbonyl oxygen and is sufficiently energetic to decay by water loss at the ionization onset. The slope of the breakdown curves, quantum chemical calculations, and selective deuteration of the carboxylic hydrogens establish the dissociative photoionization mechanism. After ionization, one γ-methylene hydrogen and the two carboxylic hydrogens are randomized prior to H2O loss. On the basis of the deuteration degree in the H2O + CO-loss product at higher energies, a direct water-loss channel without complete randomization also exists. The breakdown diagram and center of gravity of the H2O + CO-loss peak were modeled to obtain 0 K appearance energies of 10.77, 10.32, and 11.53 eV for H2O + CO loss, CH2COOH loss, and H2O + CH2COOH loss from adipic acid. These agree well with the CBS-QB3 calculated values of 10.68, 10.45, and 11.57 eV, respectively, which shows that threshold photoionization can yield energetics data as long as the dissociation is statistical, even when the parent ion cannot be observed. The results can be used as a starting point for a deeper understanding of the ionization and low-energy fragmentation of organic aerosol components. PMID:27100102

  11. Silencing of ABCC13 transporter in wheat reveals its involvement in grain development, phytic acid accumulation and lateral root formation.

    Bhati, Kaushal Kumar; Alok, Anshu; Kumar, Anil; Kaur, Jagdeep; Tiwari, Siddharth; Pandey, Ajay Kumar

    2016-07-01

    Low phytic acid is a trait desired in cereal crops and can be achieved by manipulating the genes involved either in its biosynthesis or its transport in the vacuoles. Previously, we have demonstrated that the wheat TaABCC13 protein is a functional transporter, primarily involved in heavy metal tolerance, and a probable candidate gene to achieve low phytate wheat. In the current study, RNA silencing was used to knockdown the expression of TaABCC13 in order to evaluate its functional importance in wheat. Transgenic plants with significantly reduced TaABCC13 transcripts in either seeds or roots were selected for further studies. Homozygous RNAi lines K1B4 and K4G7 exhibited 34-22% reduction of the phytic acid content in the mature grains (T4 seeds). These transgenic lines were defective for spike development, as characterized by reduced grain filling and numbers of spikelets. The seeds of transgenic wheat had delayed germination, but the viability of the seedlings was unaffected. Interestingly, early emergence of lateral roots was observed in TaABCC13-silenced lines as compared to non-transgenic lines. In addition, these lines also had defects in metal uptake and development of lateral roots in the presence of cadmium stress. Our results suggest roles of TaABCC13 in lateral root initiation and enhanced sensitivity towards heavy metals. Taken together, these data demonstrate that wheat ABCC13 is functionally important for grain development and plays an important role during detoxification of heavy metals. PMID:27342224

  12. A fen Peat Nearby Regensburg (Bavaria, Germany) as an Archive for the Reconstruction of Past Environmental Conditions in a Prehistoric Settlement Area

    Raab, A.; Voelkel, J.; Bruetzke, W.; Kunz, S.

    2008-12-01

    Within the frame of the DFG-funded project "Peat, colluvisols and soils as archives for the reconstruction of the palaeoenvironment in the Regensburger Altsiedelland (Burgweinting, City of Regensburg)" multi- disciplinary studies are carried out to reveal past environmental conditions and effects of humans on local and regional ecosystem. The study site Regensburg-Burgweinting lies at the outskirts south-east of the City of Regensburg (Bavaria, Germany). The climate is continental with an annual mean air temperature of 8 - 9°C and a mean annual precipitation of 600 - 700 mm. The study site is situated on the loess covered high terrace of the Danube river. In the south of the high terrace the Lower Bavarian Tertiary Hills border. Due to the good climatic and edaphic conditions, this area is settled since the Palaeolithic Period. Since 1994, an archaeological excavation takes place in advance of municipal building activities. Meanwhile an area of c. 40 ha is excavated. The main geoarchive is a fen (c. 5.4 ha large), situated along the Islinger Muehlbach, c. 500 - 1000 m south-west of the excavation site. The fen developed in a topographic depression at the border from the high terrace to the Lower Bavarian Tertiary Hills. It is mainly fed by ground water from the underlying jurassic limestone as aquifer. Stratigraphic prospection of the fen by hand drillings shows, that the peat is up to 5.50 m thick. Based on the stratigraphic information, three long peat cores from the centre of the fen were recovered with a Russian peat corer and three peat/colluvial sequences were gained from the margin of the fen by percussion drilling. As a main core, profile 7038-302 was selected, since the peat sequence is complete and undisturbed with exception of the uppermost c. 50 cm section. The profile was subsampled in 1 cm increments and herefrom 1 cm3 peat was sampled for palynological investigation. Analyses of the sediment samples include bulk analyses of total contents of CNS

  13. Interaction indole-3-acetic acid IAA with lectin Canavalia maritima seeds reveal new function of lectins in plant physiology

    Silva Filho, J.C.; Santi-Gadelha, T.; Gadelha, C.A.A.; Delatorre, P. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Teixeira, C.S.; Rocha, B.A.M.; Nobrega, R.B.; Alencar, K.L.L.; Cavada, B.S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil)

    2012-07-01

    Full text: Lectins are a class of proteins of non-immune origin characterized by its capability in interacts specifically and reversibly to mono and oligosaccharides. In plant several possible roles have been suggested including their function in seed maturation, cell wall assembly, defense mechanisms, or rhizobial nodulation of legume roots. Nearly all application and proposed of the plant lectins are based on their specific carbohydrate binding. However, it has been reported that lectins from legumes, might interact with other molecules, such as non proteic amino acids and hydrophobic compounds. This study show the first the crystal structure based on molecular replacement of the Canavalia maritima (CML) complexed with IAA correlated with possible role in plant development. Purified CML was dissolved in 20 mMTrisHCl pH 7.6 containing 5 mM IAA, the suitable co-crystals from CML-IAA complex grew in condition 4 of screen I (0.1 M TrisHCl pH 8.5 and 2.0 M ammonium sulfate). This crystal belong to the orthorhombic space group I222 with unit-cell parameters a = 67.1 ; b = 70.7 , c = 97.7 , The structure was refined at 2.1 of resolution to a final R factor of 20.63 % and an R free of 22.54 %. To check the relative position of the IAA molecule in relation to the biological assemble of the CML, the tetrameric structure was generate by crystallographic symmetry. IAA molecules are positioned in the central cavity. The IAA is stabilized by interacting through hydrogen bounds and Van der Waals forces with the amino acids residues Ser 108 and Asn131, and two water molecules. The hydrophilic interactions occur between IAA and side chains of Ser 108, Asn131 and water molecules 26 and 31 by H-bonds. The OG oxygen from Ser108 display H-bonds with O2 and O3 oxygen atoms from IAA, 3.1 and 2.8 respectively. The tetrameric structure of CML complexed with IAA revels which this protein can act during the seedling in plant development. (author)

  14. Interaction indole-3-acetic acid IAA with lectin Canavalia maritima seeds reveal new function of lectins in plant physiology

    Full text: Lectins are a class of proteins of non-immune origin characterized by its capability in interacts specifically and reversibly to mono and oligosaccharides. In plant several possible roles have been suggested including their function in seed maturation, cell wall assembly, defense mechanisms, or rhizobial nodulation of legume roots. Nearly all application and proposed of the plant lectins are based on their specific carbohydrate binding. However, it has been reported that lectins from legumes, might interact with other molecules, such as non proteic amino acids and hydrophobic compounds. This study show the first the crystal structure based on molecular replacement of the Canavalia maritima (CML) complexed with IAA correlated with possible role in plant development. Purified CML was dissolved in 20 mMTrisHCl pH 7.6 containing 5 mM IAA, the suitable co-crystals from CML-IAA complex grew in condition 4 of screen I (0.1 M TrisHCl pH 8.5 and 2.0 M ammonium sulfate). This crystal belong to the orthorhombic space group I222 with unit-cell parameters a = 67.1 ; b = 70.7 , c = 97.7 , The structure was refined at 2.1 of resolution to a final R factor of 20.63 % and an R free of 22.54 %. To check the relative position of the IAA molecule in relation to the biological assemble of the CML, the tetrameric structure was generate by crystallographic symmetry. IAA molecules are positioned in the central cavity. The IAA is stabilized by interacting through hydrogen bounds and Van der Waals forces with the amino acids residues Ser 108 and Asn131, and two water molecules. The hydrophilic interactions occur between IAA and side chains of Ser 108, Asn131 and water molecules 26 and 31 by H-bonds. The OG oxygen from Ser108 display H-bonds with O2 and O3 oxygen atoms from IAA, 3.1 and 2.8 respectively. The tetrameric structure of CML complexed with IAA revels which this protein can act during the seedling in plant development. (author)

  15. Fens as Whole-Ecosystem Gauges of Groundwater Recharge Under Climate Change

    Drexler, J. Z.; Knifong, D. L.; Tuil, J.; Flint, L. E.; Flint, A. L.

    2011-12-01

    Over the past century, mean air temperature has increased approximately 1 C in California. Since the 1950s, there has been an earlier onset of snowmelt and reduced snowpack (measured as snow water equivalent) in California as well as in much of the western United States. Because the snowpack is the main source of groundwater recharge in the mountainous west, reduced snowpack could result in decreased groundwater recharge through time. This could have important ramifications because groundwater recharge maintains groundwater springs, soil moisture, river baseflows and cool water temperatures. Reductions in groundwater recharge could not only impact water availability for human populations, but could also threaten long-term viability of ecosystems reliant on groundwater flows. Groundwater-fed peatlands called fens are potentially ideal ecosystems for studying changes in groundwater recharge, because they are groundwater discharge sites that rely upon corresponding recharge sites for their sustenance. When the amount of groundwater flow to a fen is reduced, the elevation of the water table decreases leading to desiccation, compaction and increased microbial oxidation of the organic soil. In cases where groundwater flow is reduced over an extended period of time, conversion of fen into wet or mesic meadow or even pine forest can occur resulting in contraction of fen boundaries. The purpose of this study is to evaluate the usefulness of fens as whole-ecosystem gauges of groundwater recharge. We studied 7 fens distributed throughout the Sierra Nevada by tracking their areas over 70+ years with aerial photography. All photos were geo-registered using the 2005 National Agricultural Inventory Program orthophotography as the base. Images were projected to UTM zone 10, NAD 83 using ArcGIS 10.0. Fen vegetation was identified in the aerial photos predominantly by (1) dark brownish-green coloring (or various shades of gray and black in black and white imagery) and (2) mottling

  16. Ecological niche of Neanderthals from Spy Cave revealed by nitrogen isotopes of individual amino acids in collagen.

    Naito, Yuichi I; Chikaraishi, Yoshito; Drucker, Dorothée G; Ohkouchi, Naohiko; Semal, Patrick; Wißing, Christoph; Bocherens, Hervé

    2016-04-01

    This study provides a refined view on the diet and ecological niche of Neanderthals. The traditional view is that Neanderthals obtained most of their dietary protein from terrestrial animals, especially from large herbivores that roamed the open landscapes. Evidence based on the conventional carbon and nitrogen isotopic composition of bulk collagen has supported this view, although recent findings based on plant remains in the tooth calculus, microwear analyses, and small game and marine animal remains from archaeological sites have raised some questions regarding this assumption. However, the lack of a protein source other than meat in the Neanderthal diet may be due to methodological difficulties in defining the isotopic composition of plants. Based on the nitrogen isotopic composition of glutamic acid and phenylalanine in collagen for Neanderthals from Spy Cave (Belgium), we show that i) there was an inter-individual dietary heterogeneity even within one archaeological site that has not been evident in bulk collagen isotopic compositions, ii) they occupied an ecological niche different from those of hyenas, and iii) they could rely on plants for up to ∼20% of their protein source. These results are consistent with the evidence found of plant consumption by the Spy Neanderthals, suggesting a broader subsistence strategy than previously considered. PMID:27086057

  17. Intracellular traffic of the lysine and glutamic acid rich protein KERP1 reveals features of endomembrane organization in Entamoeba histolytica.

    Perdomo, Doranda; Manich, Maria; Syan, Sylvie; Olivo-Marin, Jean-Christophe; Dufour, Alexandre C; Guillén, Nancy

    2016-08-01

    The development of amoebiasis is influenced by the expression of the lysine and glutamic acid rich protein 1 (KERP1), a virulence factor involved in Entamoeba histolytica adherence to human cells. Up to date, it is unknown how the protein transits the parasite cytoplasm towards the plasma membrane, specially because this organism lacks a well-defined endoplasmic reticulum (ER) and Golgi apparatus. In this work we demonstrate that KERP1 is present at the cell surface and in intracellular vesicles which traffic in a pathway that is independent of the ER-Golgi anterograde transport. The intracellular displacement of vesicles enriched in KERP1 relies on the actin-rich cytoskeleton activities. KERP1 is also present in externalized vesicles deposited on the surface of human cells. We further report the interactome of KERP1 with its association to endomembrane components and lipids. The model for KERP1 traffic here proposed hints for the first time elements of the endocytic and exocytic paths of E. histolytica. PMID:26857352

  18. Transcriptome profiling and physiological studies reveal a major role for aromatic amino acids in mercury stress tolerance in rice seedlings.

    Yun-An Chen

    Full Text Available Mercury (Hg is a serious environmental pollution threat to the planet. The accumulation of Hg in plants disrupts many cellular-level functions and inhibits growth and development, but the mechanism is not fully understood. To gain more insight into the cellular response to Hg, we performed a large-scale analysis of the rice transcriptome during Hg stress. Genes induced with short-term exposure represented functional categories of cell-wall formation, chemical detoxification, secondary metabolism, signal transduction and abiotic stress response. Moreover, Hg stress upregulated several genes involved in aromatic amino acids (Phe and Trp and increased the level of free Phe and Trp content. Exogenous application of Phe and Trp to rice roots enhanced tolerance to Hg and effectively reduced Hg-induced production of reactive oxygen species. Hg induced calcium accumulation and activated mitogen-activated protein kinase. Further characterization of the Hg-responsive genes we identified may be helpful for better understanding the mechanisms of Hg in plants.

  19. Chemical Genetic Analysis and Functional Characterization of Staphylococcal Wall Teichoic Acid 2-Epimerases Reveals Unconventional Antibiotic Drug Targets

    Mann, Paul A.; Müller, Anna; Wolff, Kerstin A.; Fischmann, Thierry; Wang, Hao; Reed, Patricia; Hou, Yan; Li, Wenjin; Müller, Christa E.; Xiao, Jianying; Murgolo, Nicholas; Sher, Xinwei; Mayhood, Todd; Sheth, Payal R.; Mirza, Asra; Labroli, Marc; Xiao, Li; McCoy, Mark; Gill, Charles J.; Pinho, Mariana G.; Schneider, Tanja; Roemer, Terry

    2016-01-01

    Here we describe a chemical biology strategy performed in Staphylococcus aureus and Staphylococcus epidermidis to identify MnaA, a 2-epimerase that we demonstrate interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Genetic inactivation of mnaA results in complete loss of WTA and dramatic in vitro β-lactam hypersensitivity in methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE). Likewise, the β-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA and MRSE infection. Interestingly, whereas MnaA serves as the sole 2-epimerase required for WTA biosynthesis in S. epidermidis, MnaA and Cap5P provide compensatory WTA functional roles in S. aureus. We also demonstrate that MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA and MRSE. We further determine the 1.9Å crystal structure of S. aureus MnaA and identify critical residues for enzymatic dimerization, stability, and substrate binding. Finally, the natural product antibiotic tunicamycin is shown to physically bind MnaA and Cap5P and inhibit 2-epimerase activity, demonstrating that it inhibits a previously unanticipated step in WTA biosynthesis. In summary, MnaA serves as a new Staphylococcal antibiotic target with cognate inhibitors predicted to possess dual therapeutic benefit: as combination agents to restore β-lactam efficacy against MRSA and MRSE and as non-bioactive prophylactic agents to prevent Staphylococcal biofilm formation. PMID:27144276

  20. Crystal structure of cardiac troponin C regulatory domain in complex with cadmium and deoxycholic acid reveals novel conformation.

    Li, Alison Yueh; Lee, Jaeyong; Borek, Dominika; Otwinowski, Zbyszek; Tibbits, Glen F; Paetzel, Mark

    2011-10-28

    The amino-terminal regulatory domain of cardiac troponin C (cNTnC) plays an important role as the calcium sensor for the troponin complex. Calcium binding to cNTnC results in conformational changes that trigger a cascade of events that lead to cardiac muscle contraction. The cardiac N-terminal domain of TnC consists of two EF-hand calcium binding motifs, one of which is dysfunctional in binding calcium. Nevertheless, the defunct EF-hand still maintains a role in cNTnC function. For its structural analysis by X-ray crystallography, human cNTnC with the wild-type primary sequence was crystallized under a novel crystallization condition. The crystal structure was solved by the single-wavelength anomalous dispersion method and refined to 2.2 Å resolution. The structure displays several novel features. Firstly, both EF-hand motifs coordinate cadmium ions derived from the crystallization milieu. Secondly, the ion coordination in the defunct EF-hand motif accompanies unusual changes in the protein conformation. Thirdly, deoxycholic acid, also derived from the crystallization milieu, is bound in the central hydrophobic cavity. This is reminiscent of the interactions observed for cardiac calcium sensitizer drugs that bind to the same core region and maintain the "open" conformational state of calcium-bound cNTnC. The cadmium ion coordination in the defunct EF-hand indicates that this vestigial calcium binding site retains the structural and functional elements that allow it to coordinate a cadmium ion. However, it is a result of, or concomitant with, large and unusual structural changes in cNTnC. PMID:21920370

  1. The identification and optimization of 2,4-diketobutyric acids as flap endonuclease 1 inhibitors.

    Tumey, L Nathan; Huck, Bayard; Gleason, Elizabeth; Wang, Jianmin; Silver, Daniel; Brunden, Kurt; Boozer, Sherry; Rundlett, Stephen; Sherf, Bruce; Murphy, Steven; Bailey, Andrew; Dent, Tom; Leventhal, Christina; Harrington, John; Bennani, Youssef L

    2004-10-01

    There have been several recent reports of chemopotentiation via inhibition of DNA repair processes. Flap endonuclease 1 (FEN1) is a key enzyme involved in base excision repair (BER), a primary pathway utilized by mammalian cells to repair DNA damage. In this report, we describe the identification and SAR of a series of 2,4-diketobutyric acid FEN1 inhibitors. PMID:15341951

  2. Conformational study reveals amino acid residues essential for hemagglutinating and anti-proliferative activities of Clematis montana lectin.

    Lu, Bangmin; Zhang, Bin; Qi, Wei; Zhu, Yanan; Zhao, Yan; Zhou, Nan; Sun, Rong; Bao, Jinku; Wu, Chuanfang

    2014-11-01

    Clematis montana lectin (CML), a novel mannose-binding lectin purified from C. montana Buch.-Ham stem (Ranunculaceae), has been proved to have hemagglutinating activity in rabbit erythrocytes and apoptosis-inducing activity in tumor cells. However, the biochemical properties of CML have not revealed and its structural information still needs to be elucidated. In this study, it was found that CML possessed quite good thermostability and alkaline resistance, and its hemagglutinating activity was bivalent metal cation dependent. In addition, hemagglutination test and fluorescence spectroscopy proved that GuHCl, urea, and sodium dodecyl sulfate could change the conformation of CML and further caused the loss of hemagglutination activity. Moreover, the changes of fluorescence spectrum indicated that the tryptophan (Trp) microenvironment conversion might be related to the conformation and bioactivities of CML. In addition, it was also found that Trp residues, arginine (Arg) residues, and sulfhydryl were important for the hemagglutinating activity of CML, but only Trp was proved to be crucial for the CML conformation. Furthermore, the Trp, Arg, and sulfhydryl-modified CML exhibited 97.17%, 76.99%, and 49.64% loss of its anti-proliferative activity, respectively, which was consistent with the alterations of its hemagglutinating activity. Given these findings, Trp residues on the surface of CML are essential for the active center to form substrate-accessible conformation and suitable environment for carbohydrate binding. PMID:25239139

  3. Proteomic Dissection of Endosperm Starch Granule Associated Proteins Reveals a Network Coordinating Starch Biosynthesis and Amino Acid Metabolism and Glycolysis in Rice Endosperms

    Yu, Huatao; Wang, Tai

    2016-01-01

    Starch biosynthesis and starch granule packaging in cereal endosperms involve a coordinated action of starch biosynthesis enzymes and coordination with other metabolisms. Because directly binding to starch granules, starch granule-associated proteins (SGAPs) are essential to understand the underlying mechanisms, however the information on SGAPs remains largely unknown. Here, we dissected developmentally changed SGAPs from developing rice endosperms from 10 to 20 days after flowering (DAF). Starch granule packaging was not completed at 10 DAF, and was finished in the central endosperm at 15 DAF and in the whole endosperm at 20 DAF. Proteomic analysis with two-dimensional differential in-gel electrophoresis and mass spectrometry revealed 115 developmentally changed SGAPs, representing 37 unique proteins. 65% of the unique proteins had isoforms. 39% of the identified SGAPs were involved in starch biosynthesis with main functions in polyglucan elongation and granule structure trimming. Almost all proteins involved in starch biosynthesis, amino acid biosynthesis, glycolysis, protein folding, and PPDK pathways increased abundance as the endosperm developed, and were predicted in an interaction network. The network represents an important mechanism to orchestrate carbon partitioning among starch biosynthesis, amino acid biosynthesis and glycolysis for efficient starch and protein storage. These results provide novel insights into mechanisms of starch biosynthesis and its coordination with amino acid metabolisms and glycolysis in cereal endosperms. PMID:27252723

  4. Direct comparison of mice null for liver or intestinal fatty acid-binding proteins reveals highly divergent phenotypic responses to high fat feeding.

    Gajda, Angela M; Zhou, Yin Xiu; Agellon, Luis B; Fried, Susan K; Kodukula, Sarala; Fortson, Walter; Patel, Khamoshi; Storch, Judith

    2013-10-18

    The enterocyte expresses two fatty acid-binding proteins (FABP), intestinal FABP (IFABP; FABP2) and liver FABP (LFABP; FABP1). LFABP is also expressed in liver. Despite ligand transport and binding differences, it has remained uncertain whether these intestinally coexpressed proteins, which both bind long chain fatty acids (FA), are functionally distinct. Here, we directly compared IFABP(-/-) and LFABP(-/-) mice fed high fat diets containing long chain saturated or unsaturated fatty acids, reasoning that providing an abundance of dietary lipid would reveal unique functional properties. The results showed that mucosal lipid metabolism was indeed differentially modified, with significant decreases in FA incorporation into triacylglycerol (TG) relative to phospholipid (PL) in IFABP(-/-) mice, whereas LFABP(-/-) mice had reduced monoacylglycerol incorporation in TG relative to PL, as well as reduced FA oxidation. Interestingly, striking differences were found in whole body energy homeostasis; LFABP(-/-) mice fed high fat diets became obese relative to WT, whereas IFABP(-/-) mice displayed an opposite, lean phenotype. Fuel utilization followed adiposity, with LFABP(-/-) mice preferentially utilizing lipids, and IFABP(-/-) mice preferentially metabolizing carbohydrate for energy production. Changes in body weight and fat may arise, in part, from altered food intake; mucosal levels of the endocannabinoids 2-arachidonoylglycerol and arachidonoylethanolamine were elevated in LFABP(-/-), perhaps contributing to increased energy intake. This direct comparison provides evidence that LFABP and IFABP have distinct roles in intestinal lipid metabolism; differential intracellular functions in intestine and in liver, for LFABP(-/-) mice, result in divergent downstream effects at the systemic level. PMID:23990461

  5. Viscosities of FenO-MgO-SiO2 and FenO-MgO-CaO-SiO2 slags

    戴曦; 甘雪萍; 张传福

    2003-01-01

    The viscosities of molten Fen O-MgO-SiO2 and Fen O-MgO-CaO-SiO2 semi-synthetic slags for nickel flash smelting were mearured in the temperature range of 1 200-1 450℃ by use of a rotational viscometer.The mass ratio of Fe to SiO2 was fixed at 1.2,calcium oxide and magnesium oxide contents varied in the range of 2%-8% and 9%-12%(mass fraction),respectively.The results show that silicate anions become smaller by increasing CaO content,which results in the viscosity decrease of slag.In the case of addition of MgO the viscosity behaviour is complicated When MgO content is less than 11%,the viscosity increases with the increase of MgO at all temperatures tested .However,when the MgO content is more than 11%,the viscosity decreases slightly for Fen O-MgO-CaOSiO2 system.At higher MgO contents,low-viscosity slags can be obtained by adding CaO.As for a given composition,the viscosity decreased with increasing temperature.The higher the temperature,the more MgO can be added before saturation.The effect of Fe3 O4 on the viscosity is quite significant.The viscosity of slag increases to 300 mpa tions of temperature and composition.A comparison between Fen O-MgO-SiO2 and Fen O-MgO-CaO-SiO2 systems are also given.

  6. NMR-based metabolomics reveals that conjugated double bond content and lipid storage efficiency in HepG2 cells are affected by fatty acid cis/trans configuration and chain length

    Najbjerg, Heidi; Young, Jette F; Bertram, Hanne Christine S.

    2011-01-01

    :0), myristic acid (C14:0), or palmitic acid (C16:0), an effect of fatty acid length was also evident, and data indicated that short-chain fatty acids (C4C6) are immediately converted, whereas mediumlong-chain fatty acids (C1216) are incorporated into triglycerides and deposited in the cells. In conclusion, the......In the present study the metabolic response to various fatty acids was investigated in HepG2 cells by using a 1HNMRbased approach. To elucidate the effect of cis/trans configuration, the cells were exposed to either oleic acid (C18:1 cis-9), elaidic acid (C18:1 trans-9), vaccenic acid (C18:1 trans......-11), linoleic acid (C18:2), or palmitic acid (C16:0), and multivariate data analysis revealed a strong effect of fatty acid on the lipophilic metabolite fraction. Inspection of the spectra revealed that the difference between the observed responses could be ascribed to the appearance of resonances...

  7. Actividad antioxidante de los compuestos fenólicos

    Maestro Durán, R.; Borja Padilla, R.

    1993-01-01

    This review deals with the oxidation processes induced by light and atmospheric oxygen, as well as the protective action on antioxidant compounds. The available data on the synthetic antioxidants and the problems associated to their use, together with the presence of natural phenolic antioxidants in plants, have been revised. These phenolic antioxidants have been classified in families: phenolic alcohols and acids, cinnamic acids, coumarins, favonoids (flavones and isoflavones, flavonols, fla...

  8. 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

    Meiya eLiu

    2016-04-01

    Full Text Available 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 acidic soils where Al stress imposed but Fe deficiency pressure released.

  9. 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

    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.

  10. Ecological restoration of rich fens in Europe and North America: from trial and error to an evidence-based approach

    Lamers, L. P. M.; M. A. Vile; A.P. Grootjans; Acreman, M. C.; Diggelen, van, MR Migchiel; Evans, M. G.; Richardson, C.J.; Rochefort, L.; Kooijman, A.M.; Roelofs, J.G.M.; Smolders, A.J.P.

    2014-01-01

    Fens represent a large array of ecosystem services, including the highest biodiversity found among wetlands, hydrological services, water purification and carbon sequestration. Land-use change and drainage has severely damaged or annihilated these services in many parts of North America and Europe; restoration plans are urgently needed at the landscape level. We review the major constraints on the restoration of rich fens and fen water bodies in agricultural areas in Europe and disturbed land...

  11. Identities among actin-encoding cDNAs of the Nile tilapia (Oreochromis niloticus and other eukaryote species revealed by nucleotide and amino acid sequence analyses

    Andréia B. Poletto

    2008-01-01

    Full Text Available Actin-encoding cDNAs of Nile tilapia (Oreochromis niloticus were isolated by RT-PCR using total RNA samples of different tissues and further characterized by nucleotide sequencing and in silico amino acid (aa sequence analysis. Comparisons among the actin gene sequences of O. niloticus and those of other species evidenced that the isolated genes present a high similarity to other fish and other vertebrate actin genes. The highest nucleotide resemblance was observed between O. niloticus and O. mossambicus a-actin and b-actin genes. Analysis of the predicted aa sequences revealed two distinct types of cytoplasmic actins, one cardiac muscle actin type and one skeletal muscle actin type that were expressed in different tissues of Nile tilapia. The evolutionary relationships between the Nile tilapia actin genes and diverse other organisms is discussed.

  12. Transcriptome and membrane fatty acid analyses reveal different strategies for responding to permeating and non-permeating solutes in the bacterium Sphingomonas wittichii

    Johnson David R

    2011-11-01

    opposite effect and decreased after perturbation with PEG8000. Conclusions A combination of growth assays, transcriptome profiling, and membrane fatty acid analyses revealed that permeating and non-permeating solutes trigger different adaptive responses in strain RW1, suggesting these solutes affect cells in fundamentally different ways. Future work is now needed that connects these responses with the responses observed in more realistic scenarios of soil desiccation.

  13. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

    Rey-Burusco, M Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R; Roe, Andrew J; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W; Córsico, Betina; Smith, Brian O

    2015-11-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  14. Examining the peat-accumulating potential of fen vegetation in the context of fed restoration of harvested peatlands

    Graf, M.; Rochefort, L. [Laval Univ., Quebec City, PQ (Canada). Dept. de Phytologie, Peatland Ecology and Research Group

    2009-07-01

    The return of peat-accumulating function is an important long-term goal in peatland restoration. However, researchers do not yet know which vegetation groups increase the ability of ecosystems to accumulate peat in fens. This study assessed the decomposition rates of 3 vegetation species typical to undisturbed fen regions, and 3 species that spontaneously colonize harvested fens. All species were incubated in a harvest fen restoration site as well as at an undisturbed fen in order to compare decomposition rates according to different environmental conditions. The study showed that the average exponential decay coefficient for all species was higher at the harvested fen site. The decay coefficient varied only slightly between undisturbed and harvested fens, despite wide variations in hydrological conditions. Litter type had the most significant impact on decomposition rates. Annual primary production of the species was also measured in order to estimate the peat accumulating capacity of each species. Results showed that Scirpus cyperinus primary annual production rates were 3 times higher than the other studied species. It was concluded that the harvested fen sites have a higher peat-accumulating potential than undisturbed fens. 60 refs., 2 tabs., 2 figs.

  15. MALDI Mass Spectrometry Imaging of Lipids and Gene Expression Reveals Differences in Fatty Acid Metabolism between Follicular Compartments in Porcine Ovaries

    Svetlana Uzbekova

    2015-03-01

    Full Text Available In mammals, oocytes develop inside the ovarian follicles; this process is strongly supported by the surrounding follicular environment consisting of cumulus, granulosa and theca cells, and follicular fluid. In the antral follicle, the final stages of oogenesis require large amounts of energy that is produced by follicular cells from substrates including glucose, amino acids and fatty acids (FAs. Since lipid metabolism plays an important role in acquiring oocyte developmental competence, the aim of this study was to investigate site-specificity of lipid metabolism in ovaries by comparing lipid profiles and expression of FA metabolism-related genes in different ovarian compartments. Using MALDI Mass Spectrometry Imaging, images of porcine ovary sections were reconstructed from lipid ion signals for the first time. Cluster analysis of ion spectra revealed differences in spatial distribution of lipid species among ovarian compartments, notably between the follicles and interstitial tissue. Inside the follicles analysis differentiated follicular fluid, granulosa, theca and the oocyte-cumulus complex. Moreover, by transcript quantification using real time PCR, we showed that expression of five key genes in FA metabolism significantly varied between somatic follicular cells (theca, granulosa and cumulus and the oocyte. In conclusion, lipid metabolism differs between ovarian and follicular compartments.

  16. Solution Structure of the Tandem Acyl Carrier Protein Domains from a Polyunsaturated Fatty Acid Synthase Reveals Beads-on-a-String Configuration

    Trujillo, Uldaeliz

    2013-02-28

    The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP

  17. Solution structure of the tandem acyl carrier protein domains from a polyunsaturated fatty acid synthase reveals beads-on-a-string configuration.

    Uldaeliz Trujillo

    Full Text Available The polyunsaturated fatty acid (PUFA synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect and in structural stabilization of the multidomain protein (synergistic effect. While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of

  18. Metabolic signatures of extreme longevity in northern Italian centenarians reveal a complex remodeling of lipids, amino acids, and gut microbiota metabolism.

    Sebastiano Collino

    Full Text Available The aging phenotype in humans has been thoroughly studied but a detailed metabolic profiling capable of shading light on the underpinning biological processes of longevity is still missing. Here using a combined metabonomics approach compromising holistic (1H-NMR profiling and targeted MS approaches, we report for the first time the metabolic phenotype of longevity in a well characterized human aging cohort compromising mostly female centenarians, elderly, and young individuals. With increasing age, targeted MS profiling of blood serum displayed a marked decrease in tryptophan concentration, while an unique alteration of specific glycerophospholipids and sphingolipids are seen in the longevity phenotype. We hypothesized that the overall lipidome changes specific to longevity putatively reflect centenarians' unique capacity to adapt/respond to the accumulating oxidative and chronic inflammatory conditions characteristic of their extreme aging phenotype. Our data in centenarians support promotion of cellular detoxification mechanisms through specific modulation of the arachidonic acid metabolic cascade as we underpinned increased concentration of 8,9-EpETrE, suggesting enhanced cytochrome P450 (CYP enzyme activity. Such effective mechanism might result in the activation of an anti-oxidative response, as displayed by decreased circulating levels of 9-HODE and 9-oxoODE, markers of lipid peroxidation and oxidative products of linoleic acid. Lastly, we also revealed that the longevity process deeply affects the structure and composition of the human gut microbiota as shown by the increased extrection of phenylacetylglutamine (PAG and p-cresol sulfate (PCS in urine of centenarians. Together, our novel approach in this representative Italian longevity cohort support the hypothesis that a complex remodeling of lipid, amino acid metabolism, and of gut microbiota functionality are key regulatory processes marking exceptional longevity in humans.

  19. Direct Comparison of Mice Null for Liver or Intestinal Fatty Acid-binding Proteins Reveals Highly Divergent Phenotypic Responses to High Fat Feeding*

    Gajda, Angela M.; Zhou, Yin Xiu; Agellon, Luis B.; Fried, Susan K.; Kodukula, Sarala; Fortson, Walter; Patel, Khamoshi; Storch, Judith

    2013-01-01

    The enterocyte expresses two fatty acid-binding proteins (FABP), intestinal FABP (IFABP; FABP2) and liver FABP (LFABP; FABP1). LFABP is also expressed in liver. Despite ligand transport and binding differences, it has remained uncertain whether these intestinally coexpressed proteins, which both bind long chain fatty acids (FA), are functionally distinct. Here, we directly compared IFABP−/− and LFABP−/− mice fed high fat diets containing long chain saturated or unsaturated fatty acids, reasoning that providing an abundance of dietary lipid would reveal unique functional properties. The results showed that mucosal lipid metabolism was indeed differentially modified, with significant decreases in FA incorporation into triacylglycerol (TG) relative to phospholipid (PL) in IFABP−/− mice, whereas LFABP−/− mice had reduced monoacylglycerol incorporation in TG relative to PL, as well as reduced FA oxidation. Interestingly, striking differences were found in whole body energy homeostasis; LFABP−/− mice fed high fat diets became obese relative to WT, whereas IFABP−/− mice displayed an opposite, lean phenotype. Fuel utilization followed adiposity, with LFABP−/− mice preferentially utilizing lipids, and IFABP−/− mice preferentially metabolizing carbohydrate for energy production. Changes in body weight and fat may arise, in part, from altered food intake; mucosal levels of the endocannabinoids 2-arachidonoylglycerol and arachidonoylethanolamine were elevated in LFABP−/−, perhaps contributing to increased energy intake. This direct comparison provides evidence that LFABP and IFABP have distinct roles in intestinal lipid metabolism; differential intracellular functions in intestine and in liver, for LFABP−/− mice, result in divergent downstream effects at the systemic level. PMID:23990461

  20. Interesting Starter Culture Strains for Controlled Cocoa Bean Fermentation Revealed by Simulated Cocoa Pulp Fermentations of Cocoa-Specific Lactic Acid Bacteria ▿

    Lefeber, Timothy; Janssens, Maarten; Moens, Frédéric; Gobert, William; De Vuyst, Luc

    2011-01-01

    Among various lactic acid bacterial strains tested, cocoa-specific strains of Lactobacillus fermentum were best adapted to the cocoa pulp ecosystem. They fermented glucose to lactic acid and acetic acid, reduced fructose to mannitol, and converted citric acid into lactic acid and 2,3-butanediol.

  1. Soil Iron Content as a Predictor of Carbon and Nutrient Mobilization in Rewetted Fens

    Emsens, Willem-Jan; Aggenbach, Camiel J. S.; Schoutens, Ken; Smolders, Alfons J. P.; Zak, Dominik; van Diggelen, Rudy

    2016-01-01

    Rewetted, previously drained fens often remain sources rather than sinks for carbon and nutrients. To date, it is poorly understood which soil characteristics stimulate carbon and nutrient mobilization upon rewetting. Here, we assess the hypothesis that a large pool of iron in the soil negatively affects fen restoration success, as flooding-induced iron reduction (Fe3+ to Fe2+) causes a disproportionate breakdown of organic matter that is coupled with a release of inorganic compounds. We collected intact soil cores in two iron-poor and two iron-rich drained fens, half of which were subjected to a rewetting treatment while the other half was kept drained. Prolonged drainage led to the mobilization of nitrate (NO3-, > 1 mmol L-1) in all cores, regardless of soil iron content. In the rewetted iron-rich cores, a sharp increase in pore water iron (Fe) concentrations correlated with concentrations of inorganic carbon (TIC, > 13 mmol L-1) and dissolved organic carbon (DOC, > 16 mmol L-1). Additionally, ammonium (NH4+) accumulated up to phytotoxic concentrations of 1 mmol L-1 in the pore water of the rewetted iron-rich cores. Disproportionate mobilization of Fe, TIC, DOC and NH4+ was absent in the rewetted iron-poor cores, indicating a strong interaction between waterlogging and iron-mediated breakdown of organic matter. Concentrations of dissolved phosphorus (P) rose slightly in all cores upon rewetting, but remained low throughout the experiment. Our results suggest that large pools of iron in the top soil of drained fens can hamper the restoration of the fen’s sink-service for ammonium and carbon upon rewetting. We argue that negative effects of iron should be most apparent in fens with fluctuating water levels, as temporary oxygenation allows frequent regeneration of Fe3+. We conclude that rewetting of iron-poor fens may be more feasible for restoration. PMID:27050837

  2. The manipulation of auxin in the abscission zone cells of Arabidopsis flowers reveals that indoleacetic acid signaling is a prerequisite for organ shedding.

    Basu, Manojit M; González-Carranza, Zinnia H; Azam-Ali, Sayed; Tang, Shouya; Shahid, Ahmad Ali; Roberts, Jeremy A

    2013-05-01

    A number of novel strategies were employed to examine the role of indoleacetic acid (IAA) in regulating floral organ abscission in Arabidopsis (Arabidopsis thaliana). Analysis of auxin influx facilitator expression in β-glucuronidase reporter plants revealed that AUXIN RESISTANT1, LIKE AUX1, and LAX3 were specifically up-regulated at the site of floral organ shedding. Flowers from mutants where individual family members were down-regulated exhibited a reduction in the force necessary to bring about petal separation; however, the effect was not additive in double or quadruple mutants. Using the promoter of a polygalacturonase (At2g41850), active primarily in cells undergoing separation, to drive expression of the bacterial genes iaaL and iaaM, we have shown that it is possible to manipulate auxin activity specifically within the floral organ abscission zone (AZ). Analysis of petal breakstrength reveals that if IAA AZ levels are reduced, shedding takes place prematurely, while if they are enhanced, organ loss is delayed. The At2g41850 promoter was also used to transactivate the gain-of-function AXR3-1 gene in order to disrupt auxin signaling specifically within the floral organ AZ cells. Flowers from transactivated lines failed to shed their sepals, petals, and anthers during pod expansion and maturity, and these organs frequently remained attached to the plant even after silique desiccation and dehiscence had taken place. These observations support a key role for IAA in the regulation of abscission in planta and reveal, to our knowledge for the first time, a requirement for a functional IAA signaling pathway in AZ cells for organ shedding to take place. PMID:23509178

  3. O fenómeno subversivo na actualidade : contributos para o seu estudo

    Garcia, Francisco Proença

    2006-01-01

    Neste estudo foi utilizada uma perspectiva holística e pluridisciplinar no sentido de alcançar a resposta a uma questão fundamental: “como pode este fenómeno ser caracterizado e apresentado?” tendo sido organizado em quatro partes. A primeira diz respeito ao fenómeno da subversão e às suas características no presente; a segunda parte foca as suas causas e a terceira tenta identificar algumas tipologias possíveis. Por fim, identifica-se e sistematiza- -se as premi...

  4. Performance of a constructed fen peatland: Reclamation of oil sands landscapes

    Price, J. S.

    2013-12-01

    Wetlands cover >60% of the landscape in the Athabasca oils sands development region. These are predominantly fen peatlands, that rely to varying extent on base-rich surface- and/or ground-water derived from adjacent mineral lands. Large areas of peatland are removed by surface stripping to access the bitumen. Reclamation of post-mined landscapes to peatland has not previously been attempted. Groundwater modeling was used to guide design choices on the optimal geometry, placement (layering) and hydraulic properties of locally available materials; these include processed tailings sand, as well peat and forest soils from newly developed lease areas. The constructed system comprises a ~3 ha fen with 2 m of peat and an adjacent upland specifically designed to supply the requisite water to maintain suitable hydrological conditions. The upland is primarily tailings sand covered by a forest soil. The constructed fen/upland system was set within a ~30 ha basin that was reclaimed using standard techniques and materials, and supplements water inputs to the designed system. Both fen and upland were placed at water contents well below equilibrium levels, so there was concern about the wetland function during the years following construction. However, in its first year following construction (2013), a higher than normal snowpack flooded the system, but by surface inflow rather than seepage from the upland. Ground-ice in the fen limited the general infiltration and percolation of meltwater into the peat, although fortuitously a localized recharge pipe developed through thermal erosion and substantially recharged the fen. Water was redistributed beneath the fen through a highly permeable sublayer (petroleum coke) designed for this purpose, and created artesian pressures. Backflow into the upland also resulted, although much of the upland remains well below design water contents. Modification of the upland soils by plowing, and development of local recharge basins, is expected to

  5. Fate and Transport of Road Salt During Snowmelt Through a Calcareous Fen: Kampoosa Bog, Stockbridge, Massachusetts

    Rhodes, A. L.; Guswa, A. J.; Pufall, A.

    2007-12-01

    Kampoosa Bog is the largest and most ecologically diverse calcareous lake-basin fen in Massachusetts. Situated within a 4.7 km2 drainage basin, the open fen (approx. 20 acres) consists of a floating mat of sedges (incl. Carex aquatilis and Cladium mariscoides) that overlie peat and lake clay deposits. Mineral weathering of marble bedrock within the drainage basin supplies highly alkaline ground and surface waters to the fen basin. The natural chemistry has been greatly altered by road salt runoff from the Massaschusetts Turnpike, and in question is whether disturbance from the Turnpike and a gas pipline has facilitated aggressive growth by the invasive species Phragmites australis. Considered to be one of the most significant rare species habitats in the state, Massachusetts has designated Kampoosa Bog an Area of Critical Environmental Concern, and a committee representing several local, regional, and state agencies, organizations, and citizens manages the wetland. The purpose of this study is to characterize the hydrologic and chemical response of the wetland during snowmelt events to understand the fate and movement of road salt (NaCl). Concentrations of Na and Cl in the fen groundwater are greatest close to the Turnpike. Concentrations decrease with distance downstream but are still greatly elevated relative to sites upstream of the Turnpike. During snowmelt events, the fen's outlet shows a sharp rise in Na and Cl concentrations at the onset of melting that is soon diluted by the added meltwater. The Na and Cl flux, however, is greatest at peak discharge, suggesting that high-flow events are significant periods of export of dissolved salts from the fen. Pure dissolution of rock salt produces an equal molar ratio between Na and Cl, and sodium and chloride imbalances in stream and ground waters suggest that ~20% of the Na is stored on cation exchange sites within the peat. The largest imbalances between Na and Cl occur deeper within the peat, where the peat is

  6. Compostos fenólicos totais e taninos condensados em frutas nativas do cerrado

    Wesley Silveira Rocha

    2011-12-01

    Full Text Available As frutas nativas do cerrado têm despertado ultimamente interesse crescente, devido às suas propriedades nutricionais e funcionais aliadas ao potencial para agregar valor e conservar a biodiversidade deste bioma. Muitos compostos fenólicos apresentam capacidade antioxidante de neutralizar a atividade de radicais livres gerados no organismo, que estão associados a diversas doenças crônico-degenerativas. O objetivo deste trabalho foi avaliar a eficiência de três soluções extratoras (acetona a 70 %, etanol a 95 % e metanol a 99,8 % e determinar os teores de compostos fenólicos em 10 espécies de frutas nativas do cerrado, utilizando o método de Folin-Ciocalteou para compostos fenólicos totais e o método da vanilina para taninos condensados. A acetona a 70 % mostrou-se como o melhor solvente extrator de compostos fenólicos totais e taninos condensados em frutos de Pouteria gardneriana, Eugenia dysenterica, E. klostzchiana, E. punicifolia, Plinia edulis, Campomanesia sp., fenólicos totais de Brosimium gaudichaudii e taninos condensados de Jaracatia spinosa. O etanol a 95 % foi mais eficiente na extração de fenólicos totais de Jaracatia spinosa e taninos condensados de Brosimium gaudichaudii; o metanol a 99,8 % foi mais eficiente na extração de taninos condensados de Eugenia dysenterica. Os teores de compostos fenólicos totais variaram entre 90 e 327 mg de ácido gálico equivalente por 100g de polpa para as espécies E. dysenterica e E. punicifolia, respectivamente. Os teores de taninos condensados variaram entre 4 e 291 mg de catequina equivalente por 100 g de polpa para as espécies E. dysenterica e E. calcyna, respectivamente. As espécies de frutas do cerrado, avaliadas neste estudo, podem ser consideradas boas fontes de compostos fenólicos totais, sendo que a natureza específica dos diferentes tipos deve ser avaliada em estudos futuros.

  7. El fenómeno de las bajeras como espacios urbanos de sociabilidad juvenil

    Azkona Fuente, Jon

    2014-01-01

    En este trabajo fin de grado se realiza un análisis del fenómeno de las bajeras juveniles como espacios de sociabilidad en la Cuenca de Pamplona-Iruñea. Este fenómeno surge como consecuencia de la exclusión social de la juventud de los espacios urbanos desarrollados por la ciudad moderna. Un modelo donde los jóvenes carecen de lugares propios para organizar su tiempo de ocio y son remitidos continuamente a los ámbitos mercantilizados y privados. Para el desarrollo de la in...

  8. Vegetation of high-altitude fens and restio marshlands of the Hottentots Holland Mountains, Western Cape, South Africa

    E. J. J. Sieben

    2004-12-01

    Full Text Available Seepages occurring at high altitudes in the Hottentots Holland Mountains (HHM (Western Cape Province. South Africa were subject to a phytosociological survey. Relevé sampling method and classification procedures of the floristic-sociological (Braun-Blanquet approach as well as numerical data analyses (numerical classification and ordination were used to reveal syn- taxonomic patterns and characterize the position of the syntaxa along major environmental gradients. Nine plant communities were recognized, three of which were classified as associations, following formal syntaxonomic and nomenclatural rules of the floristic-sociological approach Most of the studied mire communities were dominated by low-growing clonal restios (Restionaceae. whereas some consisted of other types of graminoids. The most important species determining the structure (and function of the mire communities on sandstones of the HHM include restios Anthochortus crinalis, Chondropetalum deustum.C. mucronatum, Elegia intermedia. E. thyrsifera. Restio subtilis. R. purpurascens. cyperoids Epischoenus villosus. Ficinia argy-ropa, grasses Ehrharta setacea subsp. setacea. Pentameris hirtiglumis as well as shrubs Berzelia squarrosa. Cliffortia tricuspi- data. Erica intenallaris and Grubbia rosmarinifolia. Protea lacticolor and Restio perplexus dominate a rare shale band seep­age community. There are two major groups of communities—the fens (dominated by carpets of Anthochortus crinalis and other low-growing species and the restio marshlands (mosaics of low tussocks of Restio subtilis and tall Chondropetalum mucrona­tum. The degree of soil (and water minerotrophy was found to be the most important differentiating feature between the mire (fen and restio marshland communities studied. The soils in the centre of mires were found to have high contents of peat and showed very little influence from the underlying sandstone. The soils along the mire margins had a greater admixture of

  9. Intra-specific diet shift in manila clams (Ruditapes philippinarum) as revealed by carbon and nitrogen stable isotopes and fatty acid biomarker

    Suh, Y.; Shin, K.

    2011-12-01

    Manila clams sampled in Seonjae Island, Korea with shell lengths (SL) below 19.76 mm in average showed a significantly depleted carbon and nitrogen isotope values (Pdiscrimination factors. In order to examine size-related diet shift in manila clams, R. philippinarum with different sizes that were constantly fed on known mixed microalgae for several months were sampled from Incheon Fisheries Hacheries Research Institute (IFRI). These manila clams have shown a high intra-species variation in growth rate with a maximum difference of more or less 2.30 cm. The smallest size groups (3.68±0.17 mm and 6.88±0.21 mm) obtained their nutrition from both P. tricornutum and aggregated organic matter that consists of dead or decomposed microalgae or other detritus. Bigger size groups (10.92±0.34 mm and 14.81±0.25 mm) obtained most of their energy from P.tricorutum and also from other phytoplankton unlike the biggest size group (21.15±1.02 mm) that feeds mainly on fresh microalgae of all diets fed. This variation in diet reveals that smaller clams mostly inhale dead or decomposed microalgae that sinks on the bottom while the bigger clams uptake more fresh ones that are still alive. This variation in feeding behavior could have been caused by morphological constraints such as limited siphon length. The results suggest that manila clams greater than and below 19.76 mm in average have different feeding behavior and P. tricornutum and I. galbana were the two most preferred diets for manila clams cultured in IFHRI. The result of fatty acid composition of manila clams in relation to size or growth rate suggests that fast growing clams would have rapid metabolism of fatty acids not required by the animals and an accumulation of the essential fatty acids (PUFA). In addition, their higher energy requirement and more active state of development would further diminish lipid reserve of the species.

  10. Novel Insights Into The Mode of Inhibition of Class A SHV-1 Beta-Lactamases Revealed by Boronic Acid Transition State Inhibitors

    W Ke; J Sampson; C Ori; F Prati; S Drawz; C Bethel; R Bonomo; F van den Akker

    2011-12-31

    Boronic acid transition state inhibitors (BATSIs) are potent class A and C {beta}-lactamase inactivators and are of particular interest due to their reversible nature mimicking the transition state. Here, we present structural and kinetic data describing the inhibition of the SHV-1 {beta}-lactamase, a clinically important enzyme found in Klebsiella pneumoniae, by BATSI compounds possessing the R1 side chains of ceftazidime and cefoperazone and designed variants of the latter, compounds 1 and 2. The ceftazidime and cefoperazone BATSI compounds inhibit the SHV-1 {beta}-lactamase with micromolar affinity that is considerably weaker than their inhibition of other {beta}-lactamases. The solved crystal structures of these two BATSIs in complex with SHV-1 reveal a possible reason for SHV-1's relative resistance to inhibition, as the BATSIs adopt a deacylation transition state conformation compared to the usual acylation transition state conformation when complexed to other {beta}-lactamases. Active-site comparison suggests that these conformational differences might be attributed to a subtle shift of residue A237 in SHV-1. The ceftazidime BATSI structure revealed that the carboxyl-dimethyl moiety is positioned in SHV-1's carboxyl binding pocket. In contrast, the cefoperazone BATSI has its R1 group pointing away from the active site such that its phenol moiety moves residue Y105 from the active site via end-on stacking interactions. To work toward improving the affinity of the cefoperazone BATSI, we synthesized two variants in which either one or two extra carbons were added to the phenol linker. Both variants yielded improved affinity against SHV-1, possibly as a consequence of releasing the strain of its interaction with the unusual Y105 conformation.

  11. Partitioning of habitat effects casts light on the decline of the fen orchid, Liparis loeselii

    Andersen, Dagmar Kappel; Ejrnæs, Rasmus; Minter, Martine Olesen;

    2015-01-01

    Liparis loeselii is a rare and declining orchid species restricted to rich fens in the northern hemisphere. Suggested reasons for the decline are habitat destruction, eutrophication, altered hydrology and scrub encroachment after termination of traditional management such as grazing and hay making...

  12. FEN1 participates in repair of the 5'-phosphotyrosyl terminus of DNA single-strand breaks.

    Kametani, Yukiko; Takahata, Chiaki; Narita, Takashi; Tanaka, Kiyoji; Iwai, Shigenori; Kuraoka, Isao

    2016-01-01

    Etoposide is a widely used anticancer drug and a DNA topoisomerase II (Top2) inhibitor. Etoposide produces Top2-attached single-strand breaks (Top2-SSB complex) and double-strand breaks (Top2-DSB complex) that are thought to induce cell death in tumor cells. The Top2-SSB complex is more abundant than the Top2-DSB complex. Human tyrosyl-DNA phosphodiesterase 2 (TDP2) is required for efficient repair of Top2-DSB complexes. However, the identities of the proteins involved in the repair of Top2-SSB complexes are unknown, although yeast genetic data indicate that 5' to 3' structure-specific DNA endonuclease activity is required for alternative repair of Top2 DNA damage. In this study, we purified a flap endonuclease 1 (FEN1) and xeroderma pigmentosum group G protein (XPG) in the 5' to 3' structure-specific DNA endonuclease family and synthesized single-strand break DNA substrates containing a 5'-phoshotyrosyl bond, mimicking the Top2-SSB complex. We found that FEN1 and XPG did not remove the 5'-phoshotyrosyl bond-containing DSB substrates but removed the 5'-phoshotyrosyl bond-containing SSB substrates. Under DNA repair conditions, FEN1 efficiently repaired the 5'-phoshotyrosyl bond-containing SSB substrates in the presence of DNA ligase and DNA polymerase. Therefore, FEN1 may play an important role in the repair of Top2-SSB complexes in etoposide-treated cells. PMID:26581212

  13. Effects of root mat buoyancy and heterogeneity on floating fen hydrology

    Stofberg, S.F.; Engelen, van Joeri; Witte, J.Ph.M.; Zee, van der S.E.A.T.M.

    2016-01-01

    Floating fen ecosystems are home to several protected habitats and species. Their development and conservation require special
    attention regarding water management. Although they are known to be heterogeneous and partially buoyant, their root mats are
    simulated in hydrological models as homo

  14. O duplo como fenômeno psíquico

    Marta Regina de Leão D'Agord

    2013-09-01

    Full Text Available Neste trabalho, analisamos um fenômeno psíquico com o qual se ocupa a psicopatologia: o fenômeno do duplo (Doppelgänger, enquanto visão angustiante de si próprio como um outro. Na psicanálise, o duplo pode ser estudado através da concepção do estádio do espelho e do modelo óptico, tais como propostos por Lacan. Entre as elaborações literárias desse fenômeno universal, destacam-se "William Wilson", de E. A. Poe, e "O duplo" de F. Dostoiévski, que se situam no fantástico enquanto gênero literário. Em nossa análise do fenômeno do duplo, realizamos uma comparação entre modelos literários e psicanalíticos.

  15. Structure and Magnetic Properties of Fe-N Films Prepared by Dual Ion Beam Sputtering

    诸葛兰剑; 吴雪梅; 汤乃云; 叶春兰; 姚伟国

    2001-01-01

    Fe-N films were prepared on Si substrate by dual ion beam sputtering (DIBS). It is of the films were investigated by a vibrating sample magnetometer (VSM). The structure of the films is insensitive to the ratios of N2/Ar in main ion source(MIS), and is mainly influenced by the substrate temperature (Ts).``

  16. Differentiation of fen bedrock in the Ełk Lakeland (NE Poland in relation to late Pleistocene terrain morphogenesis

    Lemkowska Bożena

    2015-12-01

    Full Text Available The Ełk Lakeland (NE Poland with the area of 263 100 ha was formed during Vistulian glaciation. More than 66% of this region was shaped during the Leszno phase, 15% during the Poznań phase, and 19% during the Pomeranian phase. There are 1854 fens which cover the area of 7.3 % of the Ełk Lakeland mesoregion. Fens have an area of 10.3 ha on average. About 82.5% of the studied fens is located on gyttja deposits, which suggests post-lacustrine origin of the wetlands. Primary the lakes had covered 11% of the Ełk Lakeland, and 6.3% was transformed into fens. Most of them (60% was formed on organic gyttja, 16% on calcareous gyttja, and 6% on clay gyttja. About 17.5% of fens was formed as a result of paludification. The types of bedrock underlying peats differ depending on the phases of glaciation.

  17. Dissolved organic carbon in a constructed and natural fens in the Athabasca oil sands region, Alberta, Canada.

    Khadka, Bhupesh; Munir, Tariq M; Strack, Maria

    2016-07-01

    In the Athabasca oil sands region near Fort McMurray, Alberta, Canada, peatlands are disturbed extensively in order to recover bitumen below the surface. Hence, following oil sands mining, landscape reclamation is a part of the mine closure process in order to return functioning ecosystems, including peatlands, to the region. This study was conducted at a pilot fen reclamation project and three other diverse natural (poor, rich and saline) fens in the oil sands region during the growing seasons of 2013 and 2014, the first and second year post-construction. Ecosystem functioning of the constructed fen (CF) was evaluated with reference to natural fens based on pore water dissolved organic carbon (DOC) concentration and chemistry. Significant variation of DOC concentration among the reference fens was observed, varying from an average of 42.0mg/L at the rich fen (RF) to 70.8mg/L at the saline fen (SF). Dissolved organic carbon concentration at CF was significantly lower than at all reference fens, but increased significantly over the first two years. Seasonal variation of DOC concentration was also observed in each site with concentration increasing over the growing season. At CF, DOC was comprised of larger, more humic and complex aromatic compounds than reference fens in the first year post-construction based on its spectrophotometric properties; however, these differences were reduced in the second year. Initial DOC concentration and chemistry at CF was indicative of the source being largely the peat placed during fen construction. Changes in chemistry and increasing concentration of DOC in the second growing season likely resulted from increasing inputs from plants established on site. These results suggest that DOC concentration is likely to increase in future at CF as vascular plant productivity increases and in response to salinity sourced from tailing sand used to construct the catchment. PMID:27037879

  18. Fenóis totais, flavonoides totais e atividade antioxidante de Selaginella convoluta (Arn. Spring (Selaginellaceae

    Pedro Guilherme Sousa de Sá

    2012-12-01

    Full Text Available Selaginella convoluta é uma espécie conhecida no Nordeste do Brasil como “jericó”, e bastante utilizada na medicina popular para tratamento de doenças. Este estudo teve como objetivo determinar o teor de compostos fenólicos e avaliar a atividade antioxidante in vitro do extrato etanólico e das frações obtidas por partição de S. convoluta. O conteúdo de fenóis totais foi determinado pelo método de Folin-Ciocalteu. O teor de flavonoides totais também foi avaliado. A atividade antioxidante dos extratos foi avaliada usando o método do sequestro do radical DPPH e inibição da auto-oxidação do sistema β-caroteno-ácido linoleico e comparada com os compostos de referência ácido ascórbico, BHA, BHT, quercetina e pirogalol. O conteúdo fenólico total foi de 209,90 ± 19,84 e 61,13 ± 2,50 mg equivalente de ácido gálico/g para os extratos AcOEt e EEB, respectivamente. O conteúdo de flavonoides totais foi de 155,70 ± 6,21 e 62,13 ± 4,10 para os dois extratos, respectivamente. Os extratos AcOEt e EEB apresentaram boas atividades antioxidantes. BHA foi o antioxidante mais efetivo, com um valor de IC50 de 1,62 ± 0,69 µg/mL. Os resultados obtidos mostram que S. convoluta pode ser uma boa fonte de compostos fenólicos antioxidantes. Estudos posteriores serão realizados para se chegar ao isolamento e identificação dos principais constituintes fenólicos dos extratos.

  19. Microarray Analysis Reveals Higher Gestational Folic Acid Alters Expression of Genes in the Cerebellum of Mice Offspring—A Pilot Study

    Subit Barua

    2015-01-01

    Full Text Available Folate is a water-soluble vitamin that is critical for nucleotide synthesis and can modulate methylation of DNA by altering one-carbon metabolism. Previous studies have shown that folate status during pregnancy is associated with various congenital defects including the risk of aberrant neural tube closure. Maternal exposure to a methyl supplemented diet also can alter DNA methylation and gene expression, which may influence the phenotype of offspring. We investigated if higher gestational folic acid (FA in the diet dysregulates the expression of genes in the cerebellum of offspring in C57BL/6 J mice. One week before gestation and throughout the pregnancy, groups of dams were supplemented with FA either at 2 mg/kg or 20 mg/kg of diet. Microarray analysis was used to investigate the genome wide gene expression profile in the cerebellum from day old pups. Our results revealed that exposure to the higher dose FA diet during gestation dysregulated expression of several genes in the cerebellum of both male and female pups. Several transcription factors, imprinted genes, neuro-developmental genes and genes associated with autism spectrum disorder exhibited altered expression levels. These findings suggest that higher gestational FA potentially dysregulates gene expression in the offspring brain and such changes may adversely alter fetal programming and overall brain development.

  20. Water structure at aqueous solution surfaces of atmospherically relevant dimethyl sulfoxide and methanesulfonic acid revealed by phase-sensitive sum frequency spectroscopy.

    Chen, Xiangke; Allen, Heather C

    2010-11-25

    Interfacial water structures of aqueous dimethyl sulfoxide (DMSO) and methanesulfonic acid (MSA) were studied by Raman, infrared, and conventional and phase-sensitive vibrational sum frequency generation (VSFG) spectroscopies. Through isotopic dilution, we probed bulk water hydrogen bonding strength using the vibrational frequency of dilute OD in H(2)O. As indicated by the frequency shift of the OD frequency, it is shown that DMSO has little influence on the average water hydrogen bonding strength at low concentrations in contrast with an overall weakening effect for MSA. For the water structure at the surface of aqueous solutions, although conventional VSFG spectra suggest only slight structural changes with DMSO and a red shift of hydrogen-bonded water OH frequency, phase-sensitive VSFG reveals more thoroughly structural changes in the presence of both DMSO and MSA. In the case of DMSO, reorientation of interfacial water molecules with their hydrogens pointing up toward the oxygen of the S=O group is observed. For MSA, the interfacial water structure is affected by both the dissociated methanesulfonate anions and the hydronium ions residing at the surface. Both the methanesulfonate anions and the hydronium ions have surface preference; therefore, the electric double layer (EDL) formed at the surface is relatively thin, which leads to partial reorientation of interface water molecules with net orientation of water hydrogens up. Surface DMSO molecules are more effective at reorienting surface water relative to MSA molecules. PMID:21047087

  1. The Comparative Study of Element Accumulation in Wood Fen Peat (Latvia)

    Krumins, Janis; Klavins, Maris; Kuske, Eliza; Seglins, Valdis; Kaup, Enn

    2013-04-01

    Mires belong to the most representative archives of past environmental conditions in large areas of temperate and subarctic zone. Moreover, mires keep evidence of ancient cultures and modern human activity. Consequently the research of mires is an integral part of global change studies. Fens are less studied than bogs; one of the reasons is the complexity of factors that impact peat formation. Bogs, due to dome-shaped structure, are affected by precipitation, while other external influences are negligible and simply separable. The aim of this research was the characterization of accumulation patterns of metallic elements in wood fen peat profiles and to assess their accumulation regularities in relation with peat properties. The general idea was to find out how admixtures of plant remains in different stages of decomposition change properties and the element accumulation character in a wood peat. In obtained profiles were separated five types of wood peat: wood, wood-sedge, wood-reed, wood-grass and wood- sphagnum peat. Peat was sampled in four Latvian fens: Elki, Viki, Svetupe and Sala. Similar environment, origin and development of sites suggest similar development of peat properties thus there is no reason to assume different impact on peat development among mires. Despite a slow decomposition rate, results point to a higher decomposition degree of wood peat, in comparison with other types of fen peat. In average, wood peat forms the thickest layers, but it must be taken into account that thickness depends on coating layers, presence of decomposed plant remains etc. The accumulation pattern of metallic elements in a wood fen peat slightly differs among sites, but the difference among wood peat types is clearly evident. For instance, the highest amount of iron is characteristic to wood-reed peat, while, the lowest, is in wood-sphagnum peat. At the same time, in wood-reed peat the lowest amounts of magnesium were found while the highest amount of Mg was in wood

  2. Metabolomics analysis reveals elevation of 3-indoxyl sulfate in plasma and brain during chemically-induced acute kidney injury in mice: Investigation of nicotinic acid receptor agonists

    An investigative renal toxicity study using metabolomics was conducted with a potent nicotinic acid receptor (NAR) agonist, SCH 900424. Liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) techniques were used to identify small molecule biomarkers of acute kidney injury (AKI) that could aid in a better mechanistic understanding of SCH 900424-induced AKI in mice. The metabolomics study revealed 3-indoxyl sulfate (3IS) as a more sensitive marker of SCH 900424-induced renal toxicity than creatinine or urea. An LC-MS assay for quantitative determination of 3IS in mouse matrices was also developed. Following treatment with SCH 900424, 3IS levels were markedly increased in murine plasma and brain, thereby potentially contributing to renal- and central nervous system (CNS)-related rapid onset of toxicities. Furthermore, significant decrease in urinary excretion of 3IS in those animals due to compromised renal function may be associated with the elevation of 3IS in plasma and brain. These data suggest that 3IS has a potential to be a marker of renal and CNS toxicities during chemically-induced AKI in mice. In addition, based on the metabolomic analysis other statistically significant plasma markers including p-cresol-sulfate and tryptophan catabolites (kynurenate, kynurenine, 3-indole-lactate) might be of toxicological importance but have not been studied in detail. This comprehensive approach that includes untargeted metabolomic and targeted bioanalytical sample analyses could be used to investigate toxicity of other compounds that pose preclinical or clinical development challenges in a pharmaceutical discovery and development. - Research highlights: → Nicotinic acid receptor agonist, SCH 900424, caused acute kidney injury in mice. → MS-based metabolomics was conducted to identify potential small molecule markers of renal toxicity. → 3-indoxyl-sulfate was found to be as a more sensitive marker of renal toxicity than

  3. Cross sections of the 56Fe(n ,α ) 53Cr and 54Fe(n ,α ) 51Cr reactions in the MeV region

    Wang, Zhimin; Fan, Xiao; Zhang, Luyu; Bai, Huaiyong; Chen, Jinxiang; Zhang, Guohui; Gledenov, Yu. M.; Sedysheva, M. V.; Krupa, L.; Khuukhenkhuu, G.

    2015-10-01

    Cross sections of the 56Fe(n ,α ) 53Cr and 54Fe(n ,α )51Cr reactions were measured at En=5.5 and 6.5 MeV and En=4.0 ,4.5 ,5.5 ,and 6.5 MeV , respectively, using a double-section gridded ionization chamber as the α -particle detector. Natural iron and enriched 56Fe and 54Fe foil samples were prepared. A deuterium gas target was used to produce monoenergetic neutrons through the 2H(d ,n )3He reaction. Two rounds of experiments were performed at the 4.5-MV Van de Graaff Accelerator of Peking University. The foreground and background were measured in separate runs. The neutron flux was monitored by a B F3 long counter, and the cross sections of the 238U(n ,f ) reaction were used as the standard. Present results are compared with those of the talys-1.6 code calculations, existing measurements, and evaluations.

  4. Integrated Systems Biology Analysis of Transcriptomes Reveals Candidate Genes for Acidity Control in Developing Fruits of Sweet Orange (Citrus sinensis L. Osbeck).

    Huang, Dingquan; Zhao, Yihong; Cao, Minghao; Qiao, Liang; Zheng, Zhi-Liang

    2016-01-01

    Organic acids, such as citrate and malate, are important contributors for the sensory traits of fleshy fruits. Although their biosynthesis has been illustrated, regulatory mechanisms of acid accumulation remain to be dissected. To provide transcriptional architecture and identify candidate genes for citrate accumulation in fruits, we have selected for transcriptome analysis four varieties of sweet orange (Citrus sinensis L. Osbeck) with varying fruit acidity, Succari (acidless), Bingtang (low acid), and Newhall and Xinhui (normal acid). Fruits of these varieties at 45 days post anthesis (DPA), which corresponds to Stage I (cell division), had similar acidity, but they displayed differential acid accumulation at 142 DPA (Stage II, cell expansion). Transcriptomes of fruits at 45 and 142 DPA were profiled using RNA sequencing and analyzed with three different algorithms (Pearson correlation, gene coexpression network and surrogate variable analysis). Our network analysis shows that the acid-correlated genes belong to three distinct network modules. Several of these candidate fruit acidity genes encode regulatory proteins involved in transport (such as AHA10), degradation (such as APD2) and transcription (such as AIL6) and act as hubs in the citrate accumulation gene networks. Taken together, our integrated systems biology analysis has provided new insights into the fruit citrate accumulation gene network and led to the identification of candidate genes likely associated with the fruit acidity control. PMID:27092171

  5. Efecto antioxidante y antihipertensivo de diferentes compuestos fenólicos del aceite de oliva virgen "in vitro"

    González Gómez-Navarro, Cecilia

    2009-01-01

    Consta de 2 estudios in vitro:1. La valoración de la capacidad antioxidante de 19 compuestos fenólicos del AOV, mediante la Lag Phase de los dienos conjugados de la LDL inducida por Cu2+. Los compuestos fenólicos con mayor actividad antioxidante son, en orden decreciente: luteolina, rutina, hidroxitirosol, oleuropeína y 3,4-DHPEA-EDA. La mezcla de estos 5 compuestos incrementa en 1.8 veces la suma de la Lag Phase de cada uno de los compuestos fenólicos individualmente (p

  6. Fe and N diffusion in nitrogen-rich FeN measured using neutron reflectometry

    Mukul Gupta; A Gupta; A Wildes; T Gutberlet

    2008-11-01

    Grazing incidence neutron reflectometry provides an opportunity to measure the depth profile of a thin film sample with a resolution <1 nm, in a non-destructive way. In this way the diffusion across the interfaces can also be measured. In addition, neutrons have contrast among the isotopes, making it feasible to measure the self-diffusion. In the present work, the isotope multilayers of [FeN/57 FeN]10 and [FeN/Fe15N]10 were prepared using magnetron sputtering and self-diffusion of Fe and N was investigated. It was found that N diffusion is slower compared to Fe and does not follow the atomic size dependence.

  7. Ab initio investigation of the electronic structure and the magnetic trends within equiatomic FeN

    Houari, A.; Matar, S. F.; Belkhir, M. A.

    2007-05-01

    The magnetic properties of equiatomic FeN nitride have been investigated within the density functional theory (DFT) using the augmented spherical wave method (ASW). Calculation of the energy versus volume in hypothetic rocksalt (RS), zinc-blende (ZB) and wurtzite (W) types structures show that the RS-type structure is preferred. At equilibrium, energy/volume spin polarized calculations indicate that the ground state of RS-FeN is ferromagnetic with a high moment, while ZB-FeN and W-FeN are non magnetic. The magnetovolume effects with respect to the Slater-Pauling-Friedel model are discussed. Analyses of the electronic structure (density of states and chemical bonding) are reported. A discussion of the structural and magnetic properties of FeN compound is given with respect to N local environment of Fe.

  8. Perfil fenólico de um extracto de tomilho limão

    Olívia R. Pereira; Peres, António M.; Domingues, M. R. M.; Cardoso, Susana M.

    2011-01-01

    O tomilho limão é uma espécie do género Thymus cultivada na região mediterrânica e utilizada, desde há várias décadas, no tratamento de diversas afecções respiratórias e como agente antiséptico e antifúngico [1]. Este estudo pretende contribuir para um melhor conhecimento da espécie Thymus citriodorus, através da identificação e quantificação dos seus principais compostos fenólicos. O perfil fenólico do extracto etanólico de Thymus citriodorus foi obtido por análise de cromatografia líquida d...

  9. El concepto de fenómeno en el joven Heidegger

    Francisco Lara

    2008-01-01

    El presente trabajo es una discusión del concepto de fenómeno tal y como éste se encuentra determinado en la filosofía del joven Heidegger. Con ella se pretende ir a la base que permite dilucidar en qué sentido hace éste fenomenología o, en otras palabras, qué idea de filosofía se encuentra expresada bajo el título de hermenéutica fenomenológica. Al hilo de la lectura del concepto de fenómeno como concepto filosófico, esto es, como indicación formal, nos preguntaremos: 1) cómo se toma en cons...

  10. Effects of magnetic ions on optical properties: the case of (Ga, Fe)N

    Wegscheider, M; Li Tian; Navarro-Quezada, A; Faina, B; Bonanni, A [Institute for Semiconductor and Solid State Physics, Johannes Kepler University, Altenbergerstrasse 69, A-4040, Linz (Austria); Pacuski, W [Institute of Experimental Physics, University of Warsaw, Hoza 69, PL-00-681 Warszawa (Poland); Jakiela, R; Dietl, T [Institute of Physics, Polish Academy of Sciences, aleja Lotnikow 32/46, PL 02-668 Warszawa (Poland)], E-mail: alberta.bonanni@jku.at, E-mail: dietl@ifpan.edu.pl

    2008-11-12

    Because of strong exchange interactions between localized spins and effective mass carriers, transition metal impurities in semiconductors lead to giant magneto-optical effects. Furthermore, band-gap levels derived from open d shells of magnetic impurities act as efficient recombination centers for photo-carriers. This paper reviews studies of excitonic magneto-reflectivity performed on (Ga, Fe)N epilayers, and shows how hybridization between d levels and band states, particularly strong in nitrides and oxides, renormalizes the exchange splitting of the valence band states in these systems. Photoluminescence measurements on the same structures demonstrate an increase of infrared Fe-related emission at the expense of ultraviolet near band-gap luminescence. This sensitivity of luminescence to the presence of Fe impurities is exploited to monitor the aggregation of Fe{sub x}N nanocrystals that account for the room temperature ferromagnetism of (Ga, Fe)N, but do not act as inhibitors of excitonic luminescence.

  11. Fenómenos que Organizan el Límite (Phenomena that Organize Limits)

    María Teresa Sánchez; Francisco Javier Claros; Moisés Coriat

    2007-01-01

    En este artículo se pone de manifiesto la presencia de los fenómenos de aproximación organizados por una definición de límite en el caso de las sucesiones de números reales y de las funciones reales de una variable real. La exposición incluye la caracterización de tales fenómenos, una descripción del análisis comparativo desarrollado en base a ellos entre dos definiciones formales de límite de sucesión y función, y una síntesis del estudio llevado a cabo sobre una muestra intencional de libro...

  12. Fenómenos que organizan el límite

    Claros, Francisco Javier; Sánchez, María Teresa; Coriat, Moisés

    2006-01-01

    En este artículo se pone de manifiesto la presencia de los fenómenos de aproximación organizados por una definición de límite en el caso de las sucesiones de números reales y de las funciones reales de una variable real. La exposición incluye la caracterización de tales fenómenos, una descripción del análisis comparativo desarrollado en base a ellos entre dos definiciones formales de límite de sucesión y función, y una síntesis del estudio llevado a cabo sobre una muestra intencional de libro...

  13. Arrangements of Interstitial Atoms in fcc Fe-C and Fe-N Solid Solutions

    The distribution of C and N atoms in the octahedral interstitial sites of the face-centred-cubic austenite phase of the Fe-C and the Fe-N alloys is controversial. In this work, Moessbauer experiments, the quasichemical approximation, the hard-blocking excluded-sites model, the chemical activity data, electron charge calculations and Monte Carlo simulations have been combined to advance in its understanding. A database is developed, with analyses of Moessbauer spectra using models assuming either ordered or random distributions of the interstitial atoms in the interstices around an Fe atom. The data are compared as a function the fraction of occupied sites, and various striking differences between Fe-N and Fe-C alloys are discussed. The experimental trends are confronted with predictions of combined theoretical approaches.

  14. Formation dynamics of FeN thin films on Cu(100)

    Heryadi, Dodi

    2012-01-01

    To investigate the structural and magnetic properties of thin films of FeN we have performed ab initio molecular dynamics simulations of their formation on Cu(100) substrates. The iron nitride layers exhibit a p4gm(2 × 2) reconstruction and order ferromagnetically in agreement with experiment. We establish the dynamics and time scale of the film formation as a function of the film thickness. The process is split in two phases: formation of almost flat FeN layers and optimization of the distance to the substrate. Our calculated magnetic moments are 1.67 μ B, 2.14 μ B, and 2.21 μ B for one, two, and three monolayers of iron nitride. © 2011 Elsevier B.V. All rights reserved.

  15. The nucleotide sequence of HLA-B{sup *}2704 reveals a new amino acid substitution in exon 4 which is also present in HLA-B{sup *}2706

    Rudwaleit, M.; Bowness, P.; Wordsworth, P. [John Radcliffe Hospital, Oxford (United Kingdom)

    1996-12-31

    The HLA-B27 subtype HLA-B{sup *}2704 is virtually absent in Caucasians but common in Orientals, where it is associated with ankylosing spondylitis. The amino acid sequence of HLA-B{sup *}2704 has been established by peptide mapping and was shown to differ by two amino acids from HLA-B{sup *}2705, HLA-B{sup *}2704 is characterized by a serine for aspartic acid substitution at position 77 and glutamic acid for valine at position 152. To date, however, no nucleotide sequence confirming these changes at the DNA level has been published. 13 refs., 2 figs.

  16. Ácidos fenólicos en paja de trigo. ¿Son éstos los compuestos fenólicos más importantes en la inhibición del crecimiento de las plantas?

    Fidel René Díaz Serrano; Luis Felipe Ramírez Santoyo; Marcos R. Soto Hernández; Prometeo Sánchez García; Manuel Sandoval Villa; Gabriel Alcántar González; Roberto Quintero Lizaola

    2010-01-01

    Se identificaron los principales ácidos fenólicos presentes en paja de trigo por cromatografía líquida de alta resolución (CLAR), coincidiendo en general con los ácidos fenólicos reportados en la literatura científica como los principales compuestos alelopáticos presentes en la paja de trigo. Las concentraciones de estos ácidos fenólicos, cuantificadas en los extractos metanólicos por CLAR, fueron muy bajas (entre 0.17 % y 3.06 %) en relación con la cuantificación de fenólicos solubles totale...

  17. Methanotrophic and Methanogenic Communities in Swiss Alpine Fens Dominated by Carex rostrata and Eriophorum angustifolium

    Cheema, Simrita; Zeyer, Josef; Henneberger, Ruth

    2015-01-01

    Vascular plants play a key role in controlling CH4 emissions from natural wetlands, because they influence CH4 production, oxidation, and transport to the atmosphere. Here we investigated differences in the abundance and composition of methanotrophic and methanogenic communities in three Swiss alpine fens dominated by different vascular plant species under natural conditions. The sampling locations either were situated at geographically distinct sites with different physicochemical properties...

  18. Short-Term Summer Inundation as a Measure to Counteract Acidification in Rich Fens

    Mettrop, Ivan S.; Cusell, Casper; Annemieke M Kooijman; Lamers, Leon P. M.

    2015-01-01

    In regions with intensive agriculture, water level fluctuation in wetlands has generally become constricted within narrow limits. Water authorities are, however, considering the re-establishment of fluctuating water levels as a management tool in biodiverse, base-rich fens (‘rich fens’). This includes temporary inundation with surface water from ditches, which may play an important role in counteracting acidification in order to conserve and restore biodiversity. Inundation may result in an i...

  19. Magnetization reversal of the domain structure in the anti-perovskite nitride Co3FeN investigated by high-resolution X-ray microscopy

    Hajiri, T.; Finizio, S.; Vafaee, M.; Kuroki, Y.; Ando, H.; Sakakibara, H.; Kleibert, A.; Howald, L.; Kronast, F.; Ueda, K.; Asano, H.; Kläui, M.

    2016-05-01

    We performed X-ray magnetic circular dichroism (XMCD) photoemission electron microscopy imaging to reveal the magnetic domain structure of anti-perovskite nitride Co3FeN exhibiting a negative spin polarization. In square and disc patterns, we systematically and quantitatively determined the statistics of the stable states as a function of geometry. By direct imaging during the application of a magnetic field, we revealed the magnetic reversal process in a spatially resolved manner. We compared the hysteresis on the continuous area and the square patterns from the magnetic field-dependent XMCD ratio, which can be explained as resulting from the effect of the shape anisotropy, present in nanostructured thin films.

  20. Structural stability and magnetism of FeN from first principles

    Houari, A.; Matar, S. F.; Belkhir, M. A.; Nakhl, M.

    2007-02-01

    In the framework of density-functional theory, the structural and magnetic properties of FeN mononitride have been investigated using the all-electron augmented spherical wave method with a generalized gradient approximation functional for treating the effects of exchange and correlation. Calculation of the energy versus volume in hypothetic rocksalt (RS-), zinc-blende (ZB-), and wurtzite (W)-type structures shows that the RS-type structure is more stable than the others. Spin-polarized calculation results at equilibrium volume indicate that the ground state of RS-FeN is ferromagnetic with a high moment, while ZB-FeN and W-FeN are nonmagnetic. The influence of distortions on the stability is taken into account by considering FeN in two different face-centered-tetragonal structures (fcts): fct rocksalt and fct zinc blende. The magnetovolume effects with respect to Slater-Pauling-Friedel model are discussed. The electronic structures analyzed from site- and spin-projected density of states are reported. A discussion of the structural and magnetic properties of FeN is given with respect to N local environment of Fe.

  1. El fenómeno de envejecimiento de los asfaltos Asphalts’ aging phenomenon

    Reyes Freddy

    2010-12-01

    Full Text Available En este trabajo se presenta una revisión actualizada a los resultados del estudio de los procesos de envejecimiento de los asfaltos, encontrados por diversos investigadores, con el fin de profundizar en la comprensión de este fenómeno complejo. Los antecedentes demuestran la evolución del estudio del fenómeno de envejecimiento de los asfaltos, considerado inicialmente como un proceso de endurecimiento físico y progresivamente reconocido como un fenómeno complejo con repercusiones en la durabilidad y las propiedades fisicoquímicas del asfalto. Este documento pretende ser una guía para el emprendimiento de futuras investigaciones relacionadas con el desarrollo de nuevos asfaltos y mezclas asfálticas con propiedades mejoradas.This work presents a state of the art revision of the results from studies of asphalt aging found by researchers aimed at deepening understanding of this complex phenomenon. The background shows the evolution of asphalt aging, initially considering it as physical hardening and progressively ecognizing it as a complex phenomenon having repercussions on asphalt durability and physical-chemical properties. This document aims to be a guide for understanding future investigations for developing new types and mixtures of asphalt having improved properties.

  2. EFFECTS OF TREATMENT TEMPERATURE ON THE MICROSTRUCTURE AND MAGNETIC PROPERTIES OF Fe-N THIN FILMS

    2007-01-01

    Fe-N thin films were fabricated on both 100Si and NaCl substrates by RF magnetron sputtering under low nitrogen partial pressure. The microstructure and magnetic properties of Fe-N thin films were investigated with the increase of the substrate temperature (Ts) and the annealing temperature (Ta). It is more difficult for nitrogen atoms to enter the Fe lattice under higher Ts above 150℃. The phase evolution is visible at higher Tα above 200℃. The phase transformation of α"-Fe16N2 occurred at 400℃. The change of crystal size with Ta was clearly visible from bright and dark field images.The clear high-resolution electron microscope (HREM) images of 110α, 111γ, 112α, and 200α,phases were observed. The interplanar distances from TEM (transmission electron microscope) and HREM match the calculated values very well. From the results of the vibrating sample magnetometer(VSM), the good magnetic properties of Fe-N films were obtained at 150℃ of Ts and 200℃ of Tα,respectively.

  3. Restoring sedges and mosses into frost heaving iron fens, San Juan Mountains, Colorado

    R.A. Chimner

    2011-08-01

    Full Text Available Rare iron fens in the San Juan Mountains of Colorado are frequently in poor condition due to mining, roads and ditches, which have left much of the fen completely bare of vegetation. Natural revegetation is slow to occur in the bare areas because of severe frost heave in the cold mountain climate. Therefore, experimental revegetation plots were conducted in a factorial design with mulching and no mulching, crossed with moss diaspores, sedge transplants, and moss and sedge combined. Mulching influenced surface soil temperatures by reducing the midday highs and increasing the night-time lows, which decreased the frequency and amount of frost heave. Peat moisture also modified frost heave, with the greatest frost heaving occurring near 75 % peat moisture content (water table 10–20 cm below the surface and the least when soils were either wetter or drier. Moss survival was dependent on mulch, with no moss surviving in plots without mulch. Mulching also increased sedge transplant survival. In summary, mulching significantly increased the success of vegetation restoration efforts for frost heave areas in mountain fens.

  4. Annual cycle of methane emission from a boreal fen measured by the eddy covariance technique

    The northern wetlands are one of the major sources of methane into the atmosphere. We measured annual methane emission from a boreal minerotrophic fen, Siikaneva, by the eddy covariance method. The average wintertime emissions were below 1 mg/m2/h, and the summertime emissions about 3.5 mg/m2/h. The water table depth did have any clear effect on methane emissions. During most of the year the emission depended on the temperature of peat below the water table. However, during the high and late summer the emission was independent on peat temperature as well. No diurnal cycle of methane flux was found. The total annual emission from the Siikaneva site was 12.6 g/m2. The emissions of the snow free period contributed 91% to the annual emission. The emission pulse during the snow melting period was clearly detectable but of minor importance adding only less than 3% to the annual emission. Over 20% of the carbon assimilated during the year as carbon dioxide was emitted as methane. Thus methane emission is an important component of the carbon balance of the Siikaneva fen. This indicates need of taking methane into account when studying carbon balances of northern fen ecosystems

  5. El concepto de fenómeno en el joven Heidegger

    Francisco De Lara

    2008-01-01

    Full Text Available El presente trabajo es una discusión del concepto de fenómeno tal y como éste se encuentra determinado en la filosofía del joven Heidegger. Con ella se pretende ir a la base que permite dilucidar en qué sentido hace éste fenomenología o, en otras palabras, qué idea de filosofía se encuentra expresada bajo el título de hermenéutica fenomenológica. Al hilo de la lectura del concepto de fenómeno como concepto filosófico, esto es, como indicación formal, nos preguntaremos: 1 cómo se toma en consideración lo investigado fenomenológicamente; 2 cómo debe comparecer lo así investigado y 3 si, en efecto, el concepto de fenómeno funciona siempre en Heidegger como una indicación formal o si no puede constatarse en él una cierta ambigüedad.

  6. Reclamation design for a fen wetland on a tailings sand deposit in northern Alberta

    Wytrykush, C. [Syncrude Canada Ltd., Edmonton, AB (Canada); McKenna, G.T.; Papini, A.G.; Scordo, E.B. [BGC Engineering Inc., Vancouver, BC (Canada)

    2010-07-01

    This paper discussed the first attempt at designing and constructing a fen wetland and surrounding watershed on a soft tailings deposit in the Athabasca oil sands region. Among the main design components were upland hummocks, vegetated swales, a pond for water storage, a fen wetland, and 2 perched fens. For each component, reclamation prescriptions were developed using methods from Syncrude's regulatory approvals for upland forests, advice from technical experts on wetlands, and results from an analogous wetland research program. Prior to the reclamation, a long-term research program was started to appraise the response of wetland plants to different operation treatments, including placement depth, material type, compaction, and salinity. Operation techniques were developed to glean live in-situ peat material from the top layer of the boreal forest for use in wetland reclamation. Design topography and soil material types were taken into account in developing the prescriptions, which were used to test specific research hypotheses within the instrumented research watershed.

  7. Functional characterization of flax fatty acid desaturase FAD2 and FAD3 isoforms expressed in yeast reveals a broad diversity in activity.

    Radovanovic, Natasa; Thambugala, Dinushika; Duguid, Scott; Loewen, Evelyn; Cloutier, Sylvie

    2014-07-01

    With 45 % or more oil content that contains more than 55 % alpha linolenic (LIN) acid, linseed (Linum usitatissimum L.) is one of the richest plant sources of this essential fatty acid. Fatty acid desaturases 2 (FAD2) and 3 (FAD3) are the main enzymes responsible for the Δ12 and Δ15 desaturation in planta. In linseed, the oilseed morphotype of flax, two paralogous copies, and several alleles exist for each gene. Here, we cloned three alleles of FAD2A, four of FAD2B, six of FAD3A, and seven of FAD3B into a pYES vector and transformed all 20 constructs and an empty construct in yeast. The transformants were induced in the presence of oleic (OLE) acid substrate for FAD2 constructs and linoleic (LIO) acid for FAD3. Conversion rates of OLE acid into LIO acid and LIO acid into LIN acid were measured by gas chromatography. Conversion rate of FAD2 exceeded that of FAD3 enzymes with FAD2B having a conversion rate approximately 10 % higher than FAD2A. All FAD2 isoforms were active, but significant differences existed between isoforms of both FAD2 enzymes. Two FAD3A and three FAD3B isoforms were not functional. Some nonfunctional enzymes resulted from the presence of nonsense mutations causing premature stop codons, but FAD3B-C and FAD3B-F seem to be associated with single amino acid changes. The activity of FAD3A-C was more than fivefold greater than the most common isoform FAD3A-A, while FAD3A-F was fourfold greater. Such isoforms could be incorporated into breeding lines to possibly further increase the proportion of LIN acid in linseed. PMID:24522837

  8. Functional analysis of sequences adjacent to dapE of Corynebacterium glutamicum reveals the presence of aroP, which encodes the aromatic amino acid transporter.

    Wehrmann, A; Morakkabati, S; Krämer, R; Sahm, H; Eggeling, L

    1995-01-01

    An initially nonclonable DNA locus close to a gene of L-lysine biosynthesis in Corynebacterium glutamicum was analyzed in detail. Its stepwise cloning and its functional identification by monitoring the amino acid uptakes of defined mutants, together with mechanistic studies, identified the corresponding structure as aroP, the general aromatic amino acid uptake system.

  9. Mollusc communities in Bulgarian fens: predictive power of the environment, vegetation, and spatial structure in an isolated habitat

    Horsák, M.; Hájek, Michal; Hájková, Petra; Cameron, R.; Cernohorsky, N.; Apostolova, I.

    2011-01-01

    Roč. 98, č. 8 (2011), s. 671-681. ISSN 0028-1042 Institutional research plan: CEZ:AV0Z60050516 Keywords : molluscs * spring fens * Bulgaria Subject RIV: EF - Botanics Impact factor: 2.278, year: 2011

  10. Fen Wetland Hydrology and Constraints on the Fate and Transport of Heavy Metals in the San Juan Mountains, Colorado

    McClenning, B. K.; Marcantonio, F.; Giardino, J. R.

    2009-12-01

    The interactions of a variety of geomorphic processes and a complex geology have produced spectacular landscapes throughout the San Juan Mountains. This complex geology abounds in mineral deposits that were mined from the mid 1800s through the 1990s. Unfortunately, much of this early mining impacted the streams, lakes, groundwater, and fens in this environment. Today, mining is waning and interest in restoration of this alpine environment is growing. Thus, sustainable restoration requires understanding dynamic interactions in this environment, which mandates an evaluation of the geomorphic and hydrologic processes that shape the present landscape. Fen wetlands, which have developed in geologic niches produced by the intense glaciation of the San Juans, occur throughout the area. The San Juans primarily exhibit a radial drainage pattern, which continue to feed the wetlands. The hydrology of these wetlands controls the chemical and biological processes and may be the most important factor regulating fen wetland function and development. Hydrological models can be used to simulate these processes and to evaluate management scenarios for fen restoration. Five fens, located along glaciated valley floors at elevations of greater than 3,000 m, range in area from 0.4 km2 to 0.7 km2. These fens were compared to determine the influence of their morphometry on runoff and evapotranspiration. The fen hydrology is dominated by irregularly located and poorly linked pools. We are attempting to combine saturated-unsaturated groundwater flow and transport models to study each fen. Hydrological conditions within the fens, which act as a sink or filter for heavy metals, also play a major role in determining the fate of transport of contaminants associated with prior mining activities. Indeed, preliminary studies have found higher than normal concentrations of aluminum, cadmium, copper, iron, manganese, and zinc occurring throughout the San Juan wetlands. Lead is also thought to occur

  11. Wastewater contaminant transport and treatment in a nutrient limited ribbed fen

    McCarter, C. P. R.; Price, J. S.; Branfireun, B. A.

    2015-12-01

    To minimize the discharge of wastewater contaminants from remote northern communities and mining operations, fen peatlands in sub-arctic regions are used for tertiary wastewater treatment to detain, transform, and remove these contaminants. However, there is a limited understanding of contaminant transport and treatment in fen peatlands, particularly in sub-arctic Canada. To better characterize wastewater contaminant transport and treatment in these systems, approximately 44 m3 day-1 of simulated wastewater, concentrated custom-blend fertilizer (NO3-, PO33-, and SO42-) and Cl- diluted with water, was pumped into a small 0.5 ha sub-arctic ribbed fen continuously for 47 days (July 15th -August 31st 2014). Contaminant concentration of 3 similar ribbed fens varied between 0.0-3.0 mg L-1 over the study period (May - September 2014). An exponential increase in transmissivity (2.4 to 16.8 m2 day-1) as the water table rose (~0.16 m) increased the average linear groundwater velocity (0.5 to 3.4 m day-1) and resulted in rapid SO42- (0.8 m day-1) and Cl- (1.9 m day-1) transport. Notwithstanding the rapid transport of Cl-, diffusion into inactive pores still retarded Cl- transport by a factor of 1.8. Contrary to the rapid transport of SO42- and Cl-, the other contaminants were rapidly removed from the pore water (likely through biological uptake or adsorption) and minimal transport was observed (0.29 and 0.04 m day-1 for PO33- and NO3-, respectively). Northern ribbed fens have a large capacity to detain certain wastewater contaminants (e.g., NO3- and PO33-), yet allow rapid transport of others (e.g., SO42- and Cl-). Thus, these peatlands have the potential to significantly decrease wastewater contamination in northern aquatic environment by both biogeochemical and physical processes but careful management of the hydrology is required to prevent the release of mobile contaminants.

  12. Dynamics of peat accumulation and marl flat formation in a calcareous fen, midwestern United States

    Miner, J.J.; Ketterling, D.B.

    2003-01-01

    The age and sequence of peat accumulation were investigated at a calcareous fen in northeastern Illinois, USA. The purpose of this study was to identify the processes that form and sustain marl flats, which are areas of marl or tufa substrate within the fen that contain numerous rare plant species. Geomorphic, stratigraphic, and radiocarbon evidence was used to establish the processes and chronology of peat accumulation and erosion adjacent to each marl flat. The age of the base of the peat deposit varies greatly throughout the fen, ranging from 14,679 calibrated years before present (cal. years BP) to nearly modern, indicating that colonization of the sand and gravel substrate by peat occurred throughout the period from the Late Pleistocene to present. Adjacent to one marl flat, trends in basal peat age and thickness show that peat accumulation has progressed laterally inward from both sides, suggesting that the marl flat has been infilling with peat progressively by accumulation at the margins since at least 5,370 cal. years BP or longer. A second marl flat in the fen is surrounded by older, thick peat of differing ages on either edge and is bounded by fresh scarps, indicating that the marl flat currently is expanding laterally by erosion into the preexisting peat blanket. These two examples suggest a continuously repeating process, where erosion of the accumulated peat blanket forms a marl flat, which is later covered by peat accumulation. Trends in basal peat age elsewhere in the fen suggest that other marl flats may have existed in the past that have been completely infilled with peat. This study suggests that marl flat formation is a natural process that has been occurring for millennia, continuously creating habitat for the rare plant species that occupy marl flats. There is no evidence that the marl flats at this site are indicative of anthropogenic disturbance, so that management options for these areas are limited to maintaining the quality and quantity

  13. Effects of Perfluorooctanoic Acid on Metabolic Profiles in Brain and Liver of Mouse Revealed by a High-throughput Targeted Metabolomics Approach

    Nanyang Yu; Si Wei; Meiying Li; Jingping Yang; Kan Li; Ling Jin; Yuwei Xie; Giesy, John P; Xiaowei Zhang; Hongxia Yu

    2016-01-01

    Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, can result in hepatotoxicity and neurobehavioral effects in animals. The metabolome, which serves as a connection among transcriptome, proteome and toxic effects, provides pathway-based insights into effects of PFOA. Since understanding of changes in the metabolic profile during hepatotoxicity and neurotoxicity were still incomplete, a high-throughput targeted metabolomics approach (278 metabolites) was used to investigate effects of expos...

  14. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells.

    Kevin Kolahi

    Full Text Available While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5 and lipid metabolism (GPAT3, LPCAT3. We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism.

  15. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells

    Louey, Samantha; Varlamov, Oleg; Thornburg, Kent

    2016-01-01

    While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5) and lipid metabolism (GPAT3, LPCAT3). We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism. PMID:27124483

  16. Kinetic analysis of the antibacterial activity of probiotic lactobacilli towards Salmonella enterica serovar Typhimurium reveals a role for lactic acid and other inhibitory compounds.

    Makras, Lefteris; Triantafyllou, Vagelis; Fayol-Messaoudi, Domitille; Adriany, Tom; Zoumpopoulou, Georgia; Tsakalidou, Effie; Servin, Alain; De Vuyst, Luc

    2006-04-01

    Six Lactobacillus strains including commercial probiotic ones (L. acidophilus IBB 801, L. amylovorus DCE 471, L. casei Shirota, L. johnsonii La1, L. plantarum ACA-DC 287 and L. rhamnosus GG) were investigated, through batch fermentations under controlled conditions, for their capacity to inhibit Salmonella enterica serovar Typhimurium SL1344. All lactobacilli displayed strong antibacterial activity toward this Gram-negative pathogen and significantly inhibited invasion of the pathogen into cultured human enterocyte-like Caco-2/TC7 cells. By studying the production kinetics of antibacterial activity and applying the appropriate acid and pH control samples during a killing assay, we were able to distinguish between the effect of lactic acid and other inhibitory compounds produced. The antibacterial activity of L. acidophilus IBB 801, L. amylovorus DCE 471, L. casei Shirota and L. rhamnosus GG was solely due to the production of lactic acid. The antibacterial activity of L. johnsonii La1 and L. plantarum ACA-DC 287 was due to the production of lactic acid and (an) unknown inhibitory substance(s). The latter was (were) only active in the presence of lactic acid. In addition, the lactic acid produced was responsible for significant inhibitory activity upon invasion of Salmonella into Caco-2/TC7 cells. PMID:16266797

  17. Application of protein-phenolic based coating on tomatoes (Lycopersicum esculentum Aplicação de coberturas proteicas e fenólicas em tomates (Lycopersicum esculentum

    Eliane Pereira Cipolatti

    2012-09-01

    Full Text Available The aim of this study was to investigate the use of protein-phenolic based coating made from fermented rice bran on cherry tomatoes (Lycopersicum esculentum. Tests were performed with glycerol 3% (v/v, glycerol with protein-phenolic rice bran extract (5%, glycerol with protein-phenolic extract after 96 hours of fermentation (5%, and a control (without coating. The coated cherry tomatoes were kept at room temperature for 28 days. Mass loss, pH and acidity, total soluble solids, and carotenoids were determined every 96 hours. The coating made from the biomass extract reduced the carotenoid and acidity levels in the fruits studied by 17 and 21.1%, respectively, compared to the control. The coating proved an efficient barrier to water vapor with mass loss of 57% less than the control suggesting that it can be used as an alternative for vegetable tissue conservation.Este trabalho teve como objetivo estudar a utilização de películas, à base de compostos proteicos e fenólicos provenientes de farelo de arroz fermentado, em tomates (Lycopersicum esculentum. Foram realizados testes com: glicerol 3% (v/v; glicerol com extrato fenólico e proteico do farelo de arroz (5%; glicerol com extrato fenólico e proteico da biomassa gerada em 96 hours (5%, e um controle (sem a película. Os tomates revestidos foram mantidos à temperatura ambiente durante 28 dias, sendo determinados, a cada 96 horas, os seguintes aspectos: a perda de massa, o pH e a acidez, os sólidos solúveis totais e os carotenoides. A película elaborada com os extratos da biomassa reduziu os níveis de carotenoides e acidez dos frutos estudados em 17 e 21,1%, respectivamente, em relação ao controle. A película também foi eficiente como barreira ao vapor de água; assim, com perda de massa 57% inferior à do controle, sugere-se que esta poderá ser utilizada como alternativa para conservação desse tecido vegetal.

  18. Overexpression of human fatty acid transport protein 2/very long chain acyl-CoA synthetase 1 (FATP2/Acsvl1) reveals distinct patterns of trafficking of exogenous fatty acids

    Melton, Elaina M. [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States); Center for Cardiovascular Sciences, Albany Medical College, Albany, NY (United States); Cerny, Ronald L. [Department of Chemistry, University of Nebraska, Lincoln, NE (United States); DiRusso, Concetta C. [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States); Black, Paul N., E-mail: pblack2@unl.edu [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States)

    2013-11-01

    Highlights: •Roles of FATP2 in fatty acid transport/activation contribute to lipid homeostasis. •Use of 13C- and D-labeled fatty acids provide novel insights into FATP2 function. •FATP2-dependent trafficking of FA into phospholipids results in distinctive profiles. •FATP2 functions in the transport and activation pathways for exogenous fatty acids. -- Abstract: In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4 h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The

  19. Overexpression of human fatty acid transport protein 2/very long chain acyl-CoA synthetase 1 (FATP2/Acsvl1) reveals distinct patterns of trafficking of exogenous fatty acids

    Highlights: •Roles of FATP2 in fatty acid transport/activation contribute to lipid homeostasis. •Use of 13C- and D-labeled fatty acids provide novel insights into FATP2 function. •FATP2-dependent trafficking of FA into phospholipids results in distinctive profiles. •FATP2 functions in the transport and activation pathways for exogenous fatty acids. -- Abstract: In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4 h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The

  20. Highly expressed amino acid biosynthesis genes revealed by global gene expression analysis of Salmonella enterica serovar Enteritidis during growth in whole egg are not essential for this growth

    Jakočiūnė, Dzuiga; Herrero-Fresno, Ana; Jelsbak, Lotte;

    2016-01-01

    RNA was extracted from S. Enteritidis using a modified RNA-extraction protocol. Global gene expression during growth in whole egg was compared to growth in LB-medium using DNA array method. Twenty-six genes were significantly upregulated during growth in egg; these belonged to amino acid biosynthesis......, di/oligopeptide transport system, biotin synthesis, ferrous iron transport system, and type III secretion system. Significant downregulation of 15 genes related to formate hydrogenlyase (FHL) and trehalose metabolism was observed. The results suggested that S. Enteritidis is starved for amino......-acids, biotin and iron when growing in egg. However, site specific mutation of amino acid biosynthesis genes asnA (17.3 fold upregulated), asnB (18.6 fold upregulated), asnA/asnB and, serA (12.0 fold upregulated) and gdhA (3.7 fold upregulated), did not result in growth attenuation, suggesting that biosynthesis...

  1. Evaluation on the Efficiency of Subsurface Drainage in Chiu-Fen Landslide at Northern Taiwan

    Ying, L. Y.; Lin, D. G.

    2015-12-01

    For administrative district, the Chiu-Fen landslide is situated at northern Taiwan and comes within the jurisdiction of Ruei-Fang district, New Taipei City Government. Chiu-Fen village is a famous spot for sightseeing and tourism in Southeast Asia. In the last decade, for economic purpose, a vast area of slope land in Chiu-Fen area was reclaimed into business and commercial districts. However, due to the complicated geological and hydrological conditions, improper reclamation, and lack of appropriate soil and water conservation facilities, large scale landslides are frequently triggered by typhoon rainfall and causes damages to the transportation and residential building in the community. As a consequence, the government initiated a comprehensive field investigations and remediation plans to stabilize the landslide from 1997 and the remediation works were concentrated on subsurface drainages, namely the application of drainage well (a vertical shaft with multi-level horizontal drainage boreholes). To investigate the efficiency of drainage wells on the landslide, the A1-profile in the landslide which covers the drainage wells W2 and W4 was selected for a series of rainfall seepage and slope stability analyses. In addition, a 48-hrs design rainfall with return period of 25, 50 and 100 years based on the local meteorological data bank was adopted for the analyses. The numerical results indicate the factor safety FS of the three potential sliding surfaces within A1-profile are constantly keeping greater than one (FS > 1.0) and without decreasing with the elapsed time during rainfall. This implies that the subsurface drainage works can drain off the infiltrated rainwater from a high intensity and long duration rainfall and preserve the slope stability of landslides from deterioration. Finally, the efficiency of the drainage wells can be evaluated quantitatively in terms of the time-dependent factor of safety and the pore water pressure distribution on several potential

  2. A season of heat, water vapor, total hydrocarbon, and ozone fluxes at a subarctic fen

    Moore, Kathleen E.; Fitzjarrald, David R.; Wofsy, Steven C.; Daube, Bruce C.; Munger, J. William; Bakwin, Peter S.; Crill, Patrick

    1994-01-01

    High-latitude environments are thought to play several critical roles in the global balance of radiatively active trace gases. Adequate documentation of the source and sink strengths for trace gases requires long time series of detailed measurements, including heat and moisture budgets. A fen near Schefferville, Quebec, was instrumented during the summer of 1990 for the measurement of the surface energy, radiation, and moisture balances as well as for eddy correlation estimates of ozone and methane flux. Despite the limited fetch at this site, analysis of the tower flux 'footprint' indicates that at least 80% of the flux observed originates from sources within the fen. Sensible heat fluxes averaged 25% of the daytime net radiation at the site, while the latent heat flux, determined from the energy balance, was 63%; the Bowen ratio varied from 0.2 to 0.8 from day to day, without a seasonal trend to the variation. The competing effects of rooted macrophyte development (with concomitant effects on roughness and transpiration) and the normal shift in synoptic pattern around day 200 to warm, dry conditions results in a lack of net seasonal effect on the energy partitioning. Over the period from days 170 to 230, the evaporation (167 mm) was double the rainfall, while the decline in water level was 107 mm, leaving a net runoff of 0.44 mm/d. The total hydrocarbon flux was 75-120 mg m(exp -2)/d, following a diurnal pattern similar to heat or moisture flux, while the daytime ozone flux was about -1.11 x 10(exp 11) molecules cm(exp -2)/s. A period near the end of the experiment, during week 30, produced the strongest total hydrocarbon flux, associated with warmer deep (1 m) soil temperatures, lower fen water levels, and the late summer shift in wind direction at that time. An early summer 'flush' of total hydrocarbon was not observed.

  3. Fenólicos e carotenóides totais em pitanga

    Lima Vera Lúcia Arroxelas Galvão de

    2002-01-01

    Full Text Available Em decorrência de uma ampla diversidade genética, a pitanga (Eugenia uniflora L. apresenta cor que varia do alaranjado até o vermelho escuro quase negro. Em Pernambuco, no entanto, é comum encontrá-la com coloração laranja-avermelhada. Como muitos fitoquímicos presentes em frutos exibem propriedades antioxidantes, com destaque para carotenóides e compostos fenólicos, e frente a escassez de informações sobre seus teores em pitanga, objetivou-se quantificá-los nas seleções cujos frutos apresentam coloração vermelha e roxa. Assim, foram determinados espectrofotometricamente os teores de carotenóides e fenólicos totais nos frutos destas seleções nos estádios maduro e semi-maduro. Na pitanga roxa madura e em sua película também foram determinados os teores de antocianinas, flavonóis e carotenóides totais. Os compostos fenólicos e os carotenóides totais na pitanga roxa madura encontram-se em maiores teores do que na pitanga vermelha no mesmo estádio de maturação. A seleção roxa exibiu quantidade significante de antocianinas, cujo teor foi mais elevado no fruto maduro do que no semi-maduro. Os carotenóides, antocianinas e flavonóis encontram-se mais concentrados na película do que na polpa deste fruto maduro. A presença de antocianinas, flavonóis e carotenóides totais na pitanga roxa fazem deste fruto uma fonte promissora de compostos antioxidantes cujo cultivo deveria ser estimulado.

  4. Fenómenos ligados a la validación en álgebra

    Panizza, Mabel

    2006-01-01

    El presente trabajo se inserta en una investigación sobre razonamiento matemático en el dominio del álgebra. En trabajos anteriores (Panizza, 2001; Panizza & Drouhard, 2002, 2003; Drouhard & Panizza, 2003) mostramos una tipología de generalizaciones espontáneas y diversos fenómenos ligados al control por conversión a distintos registros semióticos. En continuidad con estos trabajos, nos hemos dedicado a precisar aspectos relacionados con la capacidad de los alumnos para reconocer la necesidad...

  5. Compostos fenólicos a partir de subprodutos da indústria florestal

    Santos, Sónia Andreia Oliveira

    2012-01-01

    Em Portugal, as indústrias corticeira e de pasta de papel constituem um importante sector económico, contudo, gerando elevadas quantidades de subprodutos. Estes subprodutos poderiam ser explorados em aplicações de alto valor acrescentado, como fonte de compostos fenólicos, por exemplo, em vez de serem apenas queimados para produção de energia. Estes compostos são conhecidos pelas suas inúmeras propriedades, entre as quais, antioxidante, anti-inflamatória e anti-trombótica. ...

  6. El fenómeno de crianza y sus efectos en el contexto escolar

    Varela Nájera, Dr. Carlos; Universidad Autónoma de Sinaloa; Urtusuastegui Ibarra, Dr. Manuel Alfonso; Universidad Autónoma de Sinaloa; Santoyo Pereda, Lic. Pilar del Carmen; Universidad Autónoma de Sinaloa

    2014-01-01

    En el presente trabajo de investigación se intenta dar cuenta del vínculo entre el fenómeno de crianza y las dificultades escolares de 10 alumnos de sexto grado en una escuela primaria pública de Culiacán, Sinaloa, México. Tiene como objetivo analizar las condiciones de la crianza que inciden en las dificultades escolares de los estudiantes y que, por su carácter subjetivo, plantean limitantes a la labor educativa.  Para ello se utiliza el enfoque cualitativo y el método de estudio de casos. ...

  7. Fenómenos físicos de las nanopartículas de oro

    Luna Criado, Carlos; Castañeda Rodríguez, Diana; Rosas Torres, Rafael Alberto; Sánchez Juárez, Blanca Patricia; Mendoza Reséndez, Raquel.

    2013-01-01

    El oro ha sido uno de los materiales más preciados por el hombre desde la antigüedad por sus excelentes propiedades, entre las que destaca su hermoso color y brillo, su maleabilidad y su estabilidad química. En las últimas décadas, el interés por este material se ha incrementado al encontrar que el oro en forma de nanopartículas presenta fenómenos físicos nuevos que incrementan su potencial tecnológico. En esta contribución presentamos una breve descripción de algunos de e...

  8. Evolutionäre Algorithmen zur Ablaufoptimierung in Wartungsbahnhöfen

    Fleischmann, Jörg

    2000-01-01

    Die Bahnen sehen sich zunehmend der Konkurrenz auf der Straße und, durch EU-Richtline 91/440~EWG, auch auf der Schiene ausgesetzt. Daher sind große Anstrengungen zur Steigerung der Wettbewerbsfähigkeit und damit auch der Produktivität nötig. Daher werden immer komplexere Züge eingesetzt, deren Wartung immer aufwendiger wird, gleichzeitig werden deren Stillstandzeiten aus Produktivitätsgründen immer weiter verkürzt. Dies erfordert in den Wartungsbahnhöfen zum einen eine mögli...

  9. Study on coincidence measurement for 56Fe(n, χnγ) reaction cross section

    When measuring (n, χnγ) partial γ-ray cross section of heavy fissionable nuclei, the technique of coincidence measurement was applied to depress Compton platform and background of energy spectrum. Five energy points of 56Fe(n, χnγ) cross sections were measured directly by two Clover detectors on 600 kV Cockcroff-Walton accelerator in CIAE, and then the offline data analysis at 1238.3 keV was performed by using the coincidence technique. The result is approximately the same as direct measurement result and the availability of the technique of coincidence measurement is proved. (authors)

  10. Compostos fenólicos totais e taninos condensados em frutas nativas do cerrado

    Wesley Silveira Rocha; Renata Miranda Lopes; Dijalma Barbosa da Silva; Roberto Fontes Vieira; Joseane Padilha da Silva; Tânia da Silveira Agostini-Costa

    2011-01-01

    As frutas nativas do cerrado têm despertado ultimamente interesse crescente, devido às suas propriedades nutricionais e funcionais aliadas ao potencial para agregar valor e conservar a biodiversidade deste bioma. Muitos compostos fenólicos apresentam capacidade antioxidante de neutralizar a atividade de radicais livres gerados no organismo, que estão associados a diversas doenças crônico-degenerativas. O objetivo deste trabalho foi avaliar a eficiência de três soluções extratoras (acetona a 7...

  11. Phase Transformations and Phase Equilibria in the Fe-N System at Temperatures below 573 K

    Malinov, S.; Böttger, A.J.; Mittemeijer, E.J.;

    2001-01-01

    The phase transformations of homogeneous Fe-N alloys of nitrogen contents from 10 to 26 at. pct were investigated by means of X-ray diffraction analysis upon aging in the temperature range from 373 to 473 K. It was found that precipitation of alpha double prime-Fe16N2 below 443 K does not only...... occur upon aging of supersaturated alpha (ferrite) and alpha prime (martensite), but also upon transformation of gamma prime-Fe4N1-z and epsilon-Fe2N1-x (...

  12. Atmospheric methane sources: Alaskan tundra bogs, an alpine fen, and a subarctic boreal marsh

    Sebacher, Daniel I.; Harriss, Robert C.; Bartlett, Karen B.; Sebacher, Shirley M.; Grice, Shirley S.

    2011-01-01

    Methane (CH4) flux measurements from Alaskan tundra bogs, an alpine fen, and a subarctic boreal marsh were obtained at field sites ranging from Prudhoe Bay on the coast of the Arctic Ocean to the Alaskan Range south of Fairbanks during August 1984. In the tundra, average CH4 emission rates varied from 4.9 mg CH4 m-2 d-1 (moist tundra) to 119 mg CH4 m-2 d-1 (waterlogged tundra). Fluxes averaged 40 mg CH4 m-2 d-1 from wet tussock meadows in the Brooks Range and 289 mg CH4 m-2 d-1 from an alpine...

  13. Substituent-specific antibody against glucuronoxylan reveals close association of glucuronic acid and acetyl substituents and distinct labeling patterns in tree species

    Koutaniemi, Sanna; Guillon, Fabienne; Tranquet, Olivier; Bouchet, Brigitte; Tuomainen, Päivi; Virkki, Liisa; Pedersen, Henriette Lodberg; Willats, William George Tycho; Saulnier, Luc; Tenkanen, Maija

    2012-01-01

    antibody binding. The treatment removed acetyl groups from xylan, indicating that the vicinity of glucuronic acid substituents is also acetylated. The novel labeling patterns observed in the xylem of tree species suggested that differences within the cell wall exist both in acetylation degree and in...

  14. Highly expressed amino acid biosynthesis genes revealed by global gene expression analysis of Salmonella enterica serovar Enteritidis during growth in whole egg are not essential for this growth.

    Jakočiūnė, Džiuginta; Herrero-Fresno, Ana; Jelsbak, Lotte; Olsen, John Elmerdahl

    2016-05-01

    Salmonella enterica serovar Enteritidis (S. Enteritidis) is the most common cause of egg borne salmonellosis in many parts of the world. This study analyzed gene expression of this bacterium during growth in whole egg, and whether highly expressed genes were essential for the growth. High quality RNA was extracted from S. Enteritidis using a modified RNA-extraction protocol. Global gene expression during growth in whole egg was compared to growth in LB-medium using DNA array method. Twenty-six genes were significantly upregulated during growth in egg; these belonged to amino acid biosynthesis, di/oligopeptide transport system, biotin synthesis, ferrous iron transport system, and type III secretion system. Significant downregulation of 15 genes related to formate hydrogenlyase (FHL) and trehalose metabolism was observed. The results suggested that S. Enteritidis is starved for amino-acids, biotin and iron when growing in egg. However, site specific mutation of amino acid biosynthesis genes asnA (17.3 fold upregulated), asnB (18.6 fold upregulated), asnA/asnB and, serA (12.0 fold upregulated) and gdhA (3.7 fold upregulated), did not result in growth attenuation, suggesting that biosynthesis using the enzymes encoded from these genes may represent the first choice for S. Enteritidis when growing in egg, but when absent, the bacterium could use alternative ways to obtain the amino acids. PMID:26945769

  15. Transcriptome sequencing revealed the transcriptional organization at ribosome-mediated attenuation sites in Corynebacterium glutamicum and identified a novel attenuator involved in aromatic amino acid biosynthesis.

    Neshat, Armin; Mentz, Almut; Rückert, Christian; Kalinowski, Jörn

    2014-11-20

    The Gram-positive bacterium Corynebacterium glutamicum belongs to the order Corynebacteriales and is used as a producer of amino acids at industrial scales. Due to its economic importance, gene expression and particularly the regulation of amino acid biosynthesis has been investigated extensively. Applying the high-resolution technique of transcriptome sequencing (RNA-seq), recently a vast amount of data has been generated that was used to comprehensively analyze the C. glutamicum transcriptome. By analyzing RNA-seq data from a small RNA cDNA library of C. glutamicum, short transcripts in the known transcriptional attenuators sites of the trp operon, the ilvBNC operon and the leuA gene were verified. Furthermore, whole transcriptome RNA-seq data were used to elucidate the transcriptional organization of these three amino acid biosynthesis operons. In addition, we discovered and analyzed the novel attenuator aroR, located upstream of the aroF gene (cg1129). The DAHP synthase encoded by aroF catalyzes the first step in aromatic amino acid synthesis. The AroR leader peptide contains the amino acid sequence motif F-Y-F, indicating a regulatory effect by phenylalanine and tyrosine. Analysis by real-time RT-PCR suggests that the attenuator regulates the transcription of aroF in dependence of the cellular amount of tRNA loaded with phenylalanine when comparing a phenylalanine-auxotrophic C. glutamicum mutant fed with limiting and excess amounts of a phenylalanine-containing dipeptide. Additionally, the very interesting finding was made that all analyzed attenuators are leaderless transcripts. PMID:24910972

  16. Orientation Preferences of Backbone Secondary Amide Functional Groups in Peptide Nucleic Acid Complexes: Quantum Chemical Calculations Reveal an Intrinsic Preference of Cationic D-Amino Acid-Based Chiral PNA Analogues for the P-form

    Topham, Christopher M.; Smith, Jeremy C.

    2006-01-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like basepair stacking. Quantum chemical calculations on the bindin...

  17. Ecological restoration of rich fens in Europe and North America: from trial and error to an evidence-based approach.

    Lamers, Leon P M; Vile, Melanie A; Grootjans, Ab P; Acreman, Mike C; van Diggelen, Rudy; Evans, Martin G; Richardson, Curtis J; Rochefort, Line; Kooijman, Annemieke M; Roelofs, Jan G M; Smolders, Alfons J P

    2015-02-01

    Fens represent a large array of ecosystem services, including the highest biodiversity found among wetlands, hydrological services, water purification and carbon sequestration. Land-use change and drainage has severely damaged or annihilated these services in many parts of North America and Europe; restoration plans are urgently needed at the landscape level. We review the major constraints on the restoration of rich fens and fen water bodies in agricultural areas in Europe and disturbed landscapes in North America: (i) habitat quality problems: drought, eutrophication, acidification, and toxicity, and (ii) recolonization problems: species pools, ecosystem fragmentation and connectivity, genetic variability, and invasive species; and here provide possible solutions. We discuss both positive and negative consequences of restoration measures, and their causes. The restoration of wetland ecosystem functioning and services has, for a long time, been based on a trial-and-error approach. By presenting research and practice on the restoration of rich fen ecosystems within agricultural areas, we demonstrate the importance of biogeochemical and ecological knowledge at different spatial scales for the management and restoration of biodiversity, water quality, carbon sequestration and other ecosystem services, especially in a changing climate. We define target processes that enable scientists, nature managers, water managers and policy makers to choose between different measures and to predict restoration prospects for different types of deteriorated fens and their starting conditions. PMID:24698312

  18. 原子簇FenB2(n=1~6)结构和性质的DFT研究%Density Functional Theory Study on Structures and Properties of Cluster FenB2 (n=1~6)

    方志刚; 胡红智

    2006-01-01

    A hundred of clusters FenB2 (n=1~6) were designed to simulate Fe-B amorphous alloys. Clusters Fen(n=1~6) were also concerned to study the effect on the addition of metalloid element. After the clusters models were computed by density functional theory, the most stable structures of clusters were gained. Their geometric,catalytic and magnetic properties have been analyzed and discussed. From the results, it was found that the geometries of most stable clusters FenB2 (n=1~6) were isosceles triangle, diamond, triangle dipyramid, oblique triangular prism ,triangular prism with one hat, and triangular prism with two hats, respectively. Basing on the bond lengths and electronic properties, the clusters models in the present paper could reflect the local structures of FeB amorphous alloys perfectly to a certain extent. The interactions of bond Fe-B were stronger, and the bonds between metal atoms also took some action to the stability of system in clusters of rich iron content. Basing on the studies of thermodynamics, Fermi level and DOS, cluster Fe4B2 could appear more excellent catalytic properties in ammonia synthesis and nitrogen fixation process among the clusters FenB2 (n=1~6). After the study of average3d population of clusters, the average magnetic moments were gained. The calculated average magnetic moments of clusters FenB2 (n=1~6) were less than the relevant theory calculation results of clusters Fen (n=1~6) and the experimental value of pure metal Fe (5.7~6.0 B.M.), and totally appeared soft magnetism.%本文对上百个FenB2和Fen(n=1~6)原子簇模型进行密度泛函理论计算,用来模拟非晶态合金Fe-B体系的局域结构,并考察类金属元素硼的引入对体系性质的影响.将优化构型的键长和电荷分布与实验数值进行比较,发现本文所使用的原子簇模型在一定程度上可以真实、准确地反映非晶态合金Fe-B体系的局域结构.利用这些构型,我们对其键级、电子、催化以

  19. Crystallization and preliminary X-ray analysis of flap endonuclease 1 (FEN1) from Desulfurococcus amylolyticus

    Flap endonuclease 1 from D. amylolyticus was expressed, purified and crystallized by the sitting-drop vapour-diffusion method. X-ray diffraction data were collected to 2.00 Å resolution. Flap endonuclease 1 (FEN1) is a structure-specific nuclease that removes 5′-overhanging flaps in DNA repair and removes the RNA/DNA primer during maturation of the Okazaki fragment in lagging-strand DNA replication. FEN1 from the hyperthermophilic archaeon Desulfurococcus amylolyticus was expressed in Escherichia coli, purified and crystallized using the sitting-drop vapour-diffusion method with monoammonium dihydrogen phosphate as the precipitant at pH 8.3. X-ray diffraction data were collected to 2.00 Å resolution. The space group of the crystal was determined as the primitive hexagonal space group P321, with unit-cell parameters a = b = 103.76, c = 84.58 Å. The crystal contained one molecule in the asymmetric unit

  20. Fenómenos que Organizan el Límite (Phenomena that Organize Limits

    María Teresa Sánchez

    2007-03-01

    Full Text Available En este artículo se pone de manifiesto la presencia de los fenómenos de aproximación organizados por una definición de límite en el caso de las sucesiones de números reales y de las funciones reales de una variable real. La exposición incluye la caracterización de tales fenómenos, una descripción del análisis comparativo desarrollado en base a ellos entre dos definiciones formales de límite de sucesión y función, y una síntesis del estudio llevado a cabo sobre una muestra intencional de libros de texto de matemáticas.In this paper we show the presence of the phenomena of approximation organized by a definition of limit in the cases of the successions of real numbers and the real functions of one real variable. The exposition includes the characterization of such phenomena, a description of the comparative analysis, developed using them, between two formal definitions of limit of succession and function, and a synthesis of the study carried out on an intentional sample of mathematics textbooks.

  1. Environmental factors controlling fluxes of dimethyl sulfide in a New Hampshire fen

    Demello, William Zamboni; Hines, Mark E.

    1992-01-01

    The major environmental factors controlling fluxes of dimethyl sulfide (DMS) in a Sphagnum-dominated peatland were investigated in a poor fen in New Hampshire. DMS emissions from the surface of the peatland varied greatly over 24 hours and seasonally. Maximum DMS emissions occurred in summer with minima in the late fall. Temperature was the major environmental factor controlling these variabilities. There was also some evidence that the changes in water table height might have contributed to the seasonable variability in DMS emission. The influence of the water table was greater during periods of elevated temperature. DMS and MSH were the most abundant dissolved volatile sulfur compound (VSC) in the surface of the water table. Concentrations of dissolved VSC's varied with time and space throughout the fen. Dissolved MDS, MSH, and OCS in the surface of the water table were supersaturated with respect to their concentrations in the atmosphere suggesting that the peat surface was a source of VSC's in the peatland. VCS in peatlands seemed to be produced primarily by microbial processes in the anoxic surface layers of the peat rich in organic matter and inorganic sulfide. Sphagnum mosses were not a direct source of VSC's. However, they increased transport of DMS from the peat surface to the atmosphere.

  2. Measurement of 54Fe(n,2n)53Fe cross section near threshold

    A series of experiments were performed at the Princeton Plasma Physics Laboratory to measure the cross section of the 54Fe(n,2n)53Fe reaction near threshold. Measurements were made at 6 different neutron energies and cover the 1 MeV energy range from threshold (13.64 MeV) to 14.64 MeV. The 54Fe(n,2n) cross section was measured relative to the 27Al(n,p)27Mg cross section to an accuracy of a few percent. These accurate cross-section measurements will be useful in calculating damage caused by 14 MeV D-T plasma neutrons in Fe and calculating the production of the long-lived 53Mn nuclei that account for much of the buildup of long-lived radioactivity in steel structures and other ferrous materials used in the construction of fusion reactors. They will also play an important part in a new method for measuring the plasma ion temperature of a D-T plasma

  3. Gravidez na adolescência: um olhar sobre um fenômeno complexo

    Ana Cristina Garcia Dias

    2010-04-01

    Full Text Available O presente trabalho apresenta uma revisão seletiva e não sistemática da literatura a respeito do fenômeno da gestação na adolescência. Três eixos temáticos orientam a organização do trabalho: (a Riscos e problemas associados à gestação na adolescência; (b Fatores precursores relacionados à gravidez na adolescência; e (c Fatores sócio-culturais associados ao desejo de ser mãe na adolescência. Entre as conclusões, destaca-se que a gravidez na adolescência é uma experiência que pode ter consequências tanto negativas quanto positivas para os adolescentes. Além disso, o fenômeno evidencia a necessidade de intervenções voltadas à saúde sexual e reprodutiva dos adolescentes.

  4. A rainha sensual - uma análise do fenômeno Xuxa

    Jupy Júnior

    2001-02-01

    Full Text Available

    Este artigo teve como origem a monografia de graduação do curso de Comunicação Social, habilitação jornalismo, da Universidade Federal Fluminense, orientada pelo professor doutor Luís Carlos Lopes,  tendo sido apresentada em abril de 2000. A intenção é criar uma discussão a respeito dos principais mecanismos sociais, econômicos, políticos e comunicacionais que tornam possíveis fenômenos de massa como a apresentadora Xuxa Meneghel. Este trabalho tenciona exibir uma persona midiática brasileira de forte apelo junto ao público por um ponto de vista analítico. Também tenciona levantar alguns aspectos que auxiliem em uma discussão mais profunda a respeito de outros fenômenos, bastante difundidos pela televisão – principalmente -, e de que maneira isto afeta a vida das pessoas e o imaginário coletivo brasileiro.

  5. Investigations on dendrimer space reveal solid and liquid tumor growth-inhibition by original phosphorus-based dendrimers and the corresponding monomers and dendrons with ethacrynic acid motifs

    El Brahmi, Nabil; Mignani, Serge M.; Caron, Joachim; El Kazzouli, Saïd; Bousmina, Mosto M.; Caminade, Anne-Marie; Cresteil, Thierry; Majoral, Jean-Pierre

    2015-02-01

    The well-known reactive diuretic ethacrynic acid (EA, Edecrin), with low antiproliferative activities, was chemically modified and grafted onto phosphorus dendrimers and the corresponding simple branched phosphorus dendron-like derivatives affording novel nanodevices showing moderate to strong antiproliferative activities against liquid and solid tumor cell lines, respectively.The well-known reactive diuretic ethacrynic acid (EA, Edecrin), with low antiproliferative activities, was chemically modified and grafted onto phosphorus dendrimers and the corresponding simple branched phosphorus dendron-like derivatives affording novel nanodevices showing moderate to strong antiproliferative activities against liquid and solid tumor cell lines, respectively. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05983b

  6. Diversity of Anaerobic Microorganisms Involved in Long-Chain Fatty Acid Degradation in Methanogenic Sludges as Revealed by RNA-Based Stable Isotope Probing▿

    Hatamoto, Masashi; IMACHI, HIROYUKI; Yashiro, Yuto; Ohashi, Akiyoshi; Harada, Hideki

    2007-01-01

    Long-chain fatty acid (LCFA) degradation is a key step in methanogenic treatment of wastes/wastewaters containing high concentrations of lipids. However, despite the importance of LCFA-degrading bacteria, their natural diversity is little explored due to the limited availability of isolate information and the lack of appropriate molecular markers. We therefore investigated these microbes by using RNA-based stable isotope probing. We incubated four methanogenic sludges (mesophilic sludges MP a...

  7. Electronic structures and magnetic moments of Co3FeN thin films grown by molecular beam epitaxy

    We evaluated electronic structures and magnetic moments in Co3FeN epitaxial films on SrTiO3(001). The experimentally obtained hard x-ray photoemission spectra of the Co3FeN film have a good agreement with those calculated. Site averaged spin magnetic moments deduced by x-ray magnetic circular dichroism were 1.52 μB per Co atom and 2.08 μB per Fe atom at 100 K. They are close to those of Co4N and Fe4N, respectively, implying that the Co and Fe atoms randomly occupy the corner and face-centered sites in the Co3FeN unit cell

  8. A maturação fenólica em uvas tintas: comparação de metodologias

    Correia, Pedro Tiago Relvas

    2014-01-01

    A maturação fenólica em uvas tintas é uma importante ferramenta de ajuda na decisão de vindima. Com o presente trabalho pretende-se estudar uma nova metodologia de avaliação de parâmetros relacionados com a maturação fenólica das uvas tintas, em comparação com metodologias mais habituais. Neste contexto a maturação fenólica de uvas foi avaliada através de espectrofotometria de refletância difusa e através dos métodos de bancada e dos métodos baseados em espectrofotometria de infra vermelho...

  9. Analysis of a pair of END+ and END- viruses derived from the same bovine viral diarrhea virus stock reveals the amino acid determinants in Npro responsible for inhibition of type I interferon production.

    Kozasa, Takashi; Abe, Yuri; Mitsuhashi, Kazuya; Tamura, Tomokazu; Aoki, Hiroshi; Ishimaru, Masatoshi; Nakamura, Shigeyuki; Okamatsu, Masatoshi; Kida, Hiroshi; Sakoda, Yoshihiro

    2015-05-01

    The Exaltation of Newcastle disease virus (END) phenomenon is induced by the inhibition of type I interferon in pestivirus-infected cells in vitro, via proteasomal degradation of cellular interferon regulatory factor (IRF)-3 with the property of the viral autoprotease protein N(pro). Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs). However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date. In the present study, comparison of complete genome sequences of a pair of END(+) and END(-) viruses isolated from the same virus stock revealed that there were only four amino acid substitutions (D136G, I2623V, D3148G and D3502Y) between two viruses. Based on these differences, viruses with and without mutations at these positions were generated using reverse genetics. The END assay, measurements of induced type I interferon and IRF-3 detection in cells infected with these viruses revealed that the aspartic acid at position 136 in the zinc-binding TRASH motif of N(pro) was required to inhibit the production of type I interferon via the degradation of cellular IRF-3, consistently with CSFV. PMID:25648277

  10. Structure and magnetic properties of columnar Fe-N thin films deposited by direct current magnetron sputtering

    JIA Hui; WANG Xin; PANG Shao-ping; ZHENG Wei-tao; LONG Bei-hong; LI Bo

    2009-01-01

    Columnar Fe-N thin films with thickness ranging from 30 to 150 nm were deposited by direct current magnetron sputtering using an Ar/N2 gas mixture (V(N2)/V(N2+Ar)=5%) on corning glass substrates. The structure, surface morphology and magnetic properties were investigated using X-ray diffractometry(XRD), scanning electron microscopy, atomic force microscopy, transmission electron microscopy(TEM) and superconducting quantum interference magnetometry. XRD investigation shows that Fe-N films exhibit amorphous-like structures; however, TEM measurements indicate the synthesis of mixture phases of α-Fe+ζ-Fe2N+ε-Fe3N in these films. The magnetic anisotropy and coercivity of Fe-N thin films exhibit strong dependence on the film growth behavior and surface morphology. With increasing the height of Fe-N films with column structures, the coercivity increases from 7.96 kA/m to 22.28 kA/m in the direction parallel to the film surface. In perpendicular direction the coercivity only increases slightly from 39.79 kA/m to 43.77 kA/m. However, the values of anisotropy field increase from 0.79×106 to 1.44×106 A/m, which is mainly attributed to the shape anisotropy of elongated columns due to the fact that the difference of magneto-crystalline anisotropy among these Fe-N films is small. The saturation magnetizations of Fe-N films vary with increasing film thickness from 23.5 to 85.1 A-m2/kg.

  11. Peat characteristics and groundwater geochemistry of calcareous fens in the Minnesota River Basin, U.S.A

    Almendinger, J.E.; Leete, J.H.

    1998-01-01

    . Calcareous fens in Minnesota are spring-seepage peatlands with a distinctive flora of rare calciphilic species. Peat characteristics and groundwater geochemistry were determined for six calcareous fens in the Minnesota River Basin to better understand the physical structure and chemical processes associated with stands of rare vegetation. Onset of peat accumulation in three of the fens ranged from about 4,700 to 11,000 14C yrs BP and probably resulted from a combination of climate change and local hydrogeologic conditions. Most peat cores had a carbonate-bearing surface zone with greater than 10% carbonates (average 27%, dry wt basis), an underlying carbonate-depleted zone with 10% or less carbonates (average 4%), and a carbonate-bearing lower zone again with greater than 10% carbonates (average 42%). This carbonate zonation was hypothesized to result from the effect of water-table level on carbonate equilibria: carbonate precipitation occurs when the water table is above a critical level, and carbonate dissolution occurs when the water table is lower. Other processes that changed the major ion concentrations in upwelling groundwater include dilution by rain water, sulfate reduction or sulfide oxidation, and ion adsorption or exchange. Geochemical modeling indicated that average shallow water in the calcareous fens during the study period was groundwater mixed with about 6 to 13% rain water. Carbonate precipitation in the surface zone of calcareous fens could be decreased by a number of human activities, especially those that lower the water table. Such changes in shallow water geochemistry could alter the growing conditions that apparently sustain rare fen vegetation.

  12. Expression pattern of NMDA receptors reveals antiepileptic potential of apigenin 8-C-glucoside and chlorogenic acid in pilocarpine induced epileptic mice.

    Aseervatham, G Smilin Bell; Suryakala, U; Doulethunisha; Sundaram, S; Bose, P Chandra; Sivasudha, T

    2016-08-01

    The present study was aimed to evaluate the effect of apigenin 8-C-glucoside (Vitexin) and chlorogenic acid on epileptic mice induced by pilocarpine and explored its possible mechanisms. Intraperitonial administration of pilocarpine (85mg/kg) induced seizure in mice was assessed by behavior observations, which is significantly (p>0.05) reduced by apigenin 8-C-glucoside (AP8CG) (10mg/kg) and chlorogenic acid (CA) (5mg/kg), similar to diazepam. Seizure was accompanied by an imbalance in the levels of Gamma-aminobutyric acid (GABA) and glutamate in the pilocarpine administered group. Moreover, convulsion along with reduced acetylcholinesterase, increased monoamine oxidase and oxidative stress was observed in epileptic mice brain. AP8CG and CA significantly restored back to normal levels even at lower doses. Further, increased lipid peroxidation and nitrite content was also significantly attenuated by AP8CG and CA. However, CA was found to be more effective when compared to AP8CG. In addition, the mRNA expression of N-methyl-d-aspartate receptor (NMDAR), mGluR1 and mGlu5 was significantly (P≤0.05) inhibited by AP8CG and CA in a lower dose. The mRNA expression of GRIK1 did not differ significantly in any of the group and showed a similar pattern of expression. Our result shows that AP8CG and CA selectively inhibit NMDAR, mGluR1 and mGlu5 expression. Modification in the provoked NMDAR calcium response coupled with neuronal death. Hence, these findings underline that the polyphenolics, AP8CG and CA have exerted antiepileptic and neuroprotective activity by suppressing glutamate receptors. PMID:27470339

  13. Steric and allosteric effects of fatty acids on the binding of warfarin to human serum albumin revealed by molecular dynamics and free energy calculations.

    Fujiwara, Shin-Ichi; Amisaki, Takashi

    2011-01-01

    Human serum albumin (HSA) binds with drugs and fatty acids (FAs). This study was initiated to elucidate the relationship between the warfarin binding affinity of HSA and the positions of bound FA molecules. Molecular dynamics simulations of 11 HSA-warfarin-myristate complexes were performed. HSA-warfarin binding free energy was then calculated for each of the complexes by the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method. The results indicated that the magnitude of the binding free energy was smaller in HSA-warfarin complexes that had 4 or more myristate molecules than in complexes with no myristate molecules. The unfavorable effect on the HSA-warfarin binding affinity was caused sterically by the binding of a myristate molecule to the FA binding site closest to the warfarin binding site. On the other hand, the magnitude of HSA-warfarin binding free energy was largest when 3 myristate molecules were bound to the high-affinity sites. The strongest HSA-warfarin binding was attributable to favorable entropic contribution related to larger atomic fluctuations of the amino acid residues at the warfarin binding site. In the binding of 2 myristate molecules to the sites with the highest and second-highest affinities, allosteric modulation that enhanced electrostatic interactions between warfarin and some of the amino acid residues around the warfarin binding site was observed. This study clarified the structural and energetic properties of steric/allosteric effects of FAs on the HSA-warfarin binding affinity and illustrated the approach to analyze protein-ligand interactions in situations such that multiple ligands bind to the other sites of the protein. PMID:21720037

  14. Proteomic Analysis of Plasma from California Sea Lions (Zalophus californianus Reveals Apolipoprotein E as a Candidate Biomarker of Chronic Domoic Acid Toxicosis.

    Benjamin A Neely

    Full Text Available Domoic acid toxicosis (DAT in California sea lions (Zalophus californianus is caused by exposure to the marine biotoxin domoic acid and has been linked to massive stranding events and mortality. Diagnosis is based on clinical signs in addition to the presence of domoic acid in body fluids. Chronic DAT further is characterized by reoccurring seizures progressing to status epilepticus. Diagnosis of chronic DAT is often slow and problematic, and minimally invasive tests for DAT have been the focus of numerous recent biomarker studies. The goal of this study was to retrospectively profile plasma proteins in a population of sea lions with chronic DAT and those without DAT using two dimensional gel electrophoresis to discover whether individual, multiple, or combinations of protein and clinical data could be utilized to identify sea lions with DAT. Using a training set of 32 sea lion sera, 20 proteins and their isoforms were identified that were significantly different between the two groups (p<0.05. Interestingly, 11 apolipoprotein E (ApoE charge forms were decreased in DAT samples, indicating that ApoE charge form distributions may be important in the progression of DAT. In order to develop a classifier of chronic DAT, an independent blinded test set of 20 sea lions, seven with chronic DAT, was used to validate models utilizing ApoE charge forms and eosinophil counts. The resulting support vector machine had high sensitivity (85.7% with 92.3% negative predictive value and high specificity (92.3% with 85.7% positive predictive value. These results suggest that ApoE and eosinophil counts along with machine learning can perform as a robust and accurate tool to diagnose chronic DAT. Although this analysis is specifically focused on blood biomarkers and routine clinical data, the results demonstrate promise for future studies combining additional variables in multidimensional space to create robust classifiers.

  15. All-Atom Molecular Dynamics Simulations Reveal Significant Differences in Interaction between Antimycin and Conserved Amino Acid Residues in Bovine and Bacterial bc1 Complexes

    Kokhan, Oleksandr; Shinkarev, Vladimir P.

    2011-01-01

    Antimycin A is the most frequently used specific and powerful inhibitor of the mitochondrial respiratory chain. We used all-atom molecular dynamics (MD) simulations to study the dynamic aspects of the interaction of antimycin A with the Qi site of the bacterial and bovine bc1 complexes embedded in a membrane. The MD simulations revealed considerable conformational flexibility of antimycin and significant mobility of antimycin, as a whole, inside the Qi pocket. We conclude that many of the dif...

  16. Mutation of the NADH Oxidase Gene (nox) Reveals an Overlap of the Oxygen- and Acid-Mediated Stress Responses in Streptococcus mutans

    Derr, Adam M.; Faustoferri, Roberta C.; Betzenhauser, Matthew J.; Gonzalez, Kaisha; Marquis, Robert E.; Quivey, Robert G.

    2012-01-01

    NADH oxidase (Nox) is a flavin-containing enzyme used by Streptococcus mutans to reduce dissolved oxygen encountered during growth in the oral cavity. In this study, we characterized the role of the NADH oxidase in the oxidative and acid stress responses of S. mutans. A nox-defective mutant strain of S. mutans and its parental strain, the genomic type strain UA159, were exposed to various oxygen concentrations at pH values of 5 and 7 to better understand the adaptive mechanisms used by the or...

  17. Análisis del downsizing (reducción de plantilla) como fenómeno psicosocial

    CRISTÓBAL JIMÉNEZ JIMÉNEZ; JOSÉ LUIS SÁNCHEZ LAGUNA

    2005-01-01

    En este trabajo se analiza el downsizing como fenómeno recurrente y de gran actualidad en el mundo de los negocios y de las organizaciones, delimitando su concepto, señalando su incidencia y destacando sus principales características. Después de enmarcar el downsizing en el ámbito específico del Estrés Laboral, se argumenta la importancia y conveniencia de considerarlo, de pleno derecho, como fenómeno psico-socio-laboral, señalando algunas implicaciones de interés para el ámbito de los Recurs...

  18. Algumas reflexões para estabelecer a cronologia do "fenômeno transexual" (1910-1995)

    Pierre-Henri Castel

    2001-01-01

    O "fenômeno transexual" (Benjamin) é um indicador muito seguro das modificações históricas da percepção científica, mas também cultural e política da identidade sexual no século XX. Para apresentar uma cronologia e uma bibliografia escolhida desse fenômeno, este artigo propõe um fio condutor: a recusa sistemática das interpretações psicanalíticas do transexualismo pelos sexólogos, endocrinologistas e sociólogos que estudaram o problema.The "Transsexual Phenomenon" (Benjamin) is a reliable ind...

  19. Growth kinetics of thin oxide layers; oxidation of Fe and Fe-N phases at room temperature

    Kooi, Bart J.; Somers, Marcel A. J.; Mittemeijer, Eric J.

    1996-01-01

    The evolution of iron-oxide layers at room temperature on pure polycrystalline α-Fe and on the Fe-N phases γ-Fe[N], γ'-Fe4N1-x and ε-Fe2N1-z was followed in situ with Auger-Electron Spectroscopy. The observed oxidation kinetics of the Fe and Fe-N phases were interpreted using a model considering coupled fluxes of cations and (tunnelling) electrons and an electrostatic potential difference over the oxide layer changing during oxidation. It was concluded that the oxidation kinetics are largely ...

  20. Minor long-term effects of ultraviolet-B radiation on methane dynamics of a subarctic fen in Northern Finland

    Mörsky, Sami K.; Haapala, Jaana K.; Rinnan, Riikka;

    2012-01-01

    The effects of elevated ultraviolet-B (UVB) radiation on methane dynamics was studied in a natural fen in Northern Finland for three growing seasons (2003–2005). This is the first in situ study on the effects of elevated UV-B radiation on methane dynamics in a natural fen. The experimental setup....... The results emphasize the need for long-term field studies under moderately enhanced exposures to estimate whether the function and feedbacks of mire ecosystems change under increased UV-B radiation....

  1. A fluorescence-coupled assay for gamma aminobutyric acid (GABA reveals metabolic stress-induced modulation of GABA content in neuroendocrine cancer.

    Joseph E Ippolito

    Full Text Available Pathways involved in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA have been implicated in the pathogenesis of high grade neuroendocrine (NE neoplasms as well as neoplasms from a non-NE lineage. Using The Cancer Genome Atlas, overexpression of the GABA synthetic enzyme, glutamate decarboxylase 1 (GAD1, was found to be associated with decreased disease free-survival in prostate adenocarcinoma and decreased overall survival in clear cell renal cell carcinomas. Furthermore, GAD1 was found to be expressed in castrate-resistant prostate cancer cell lines, but not androgen-responsive cell lines. Using a novel fluorescence-coupled enzymatic microplate assay for GABA mediated through reduction of resazurin in a prostate neuroendocrine carcinoma (PNEC cell line, acid microenvironment-induced stress increased GABA levels while alkaline microenvironment-induced stress decreased GABA through modulation of GAD1 and glutamine synthetase (GLUL activities. Moreover, glutamine but not glucose deprivation decreased GABA through modulation of GLUL. Consistent with evidence in prokaryotic and eukaryotic organisms that GABA synthesis mediated through GAD1 may play a crucial role in surviving stress, GABA may be an important mediator of stress survival in neoplasms. These findings identify GABA synthesis and metabolism as a potentially important pathway for regulating cancer cell stress response as well as a potential target for therapeutic strategies.

  2. Structure of an acidic phospholipase A2 from Indian saw-scaled viper (Echis carinatus) at 2.6 A resolution reveals a novel intermolecular interaction.

    Jasti, Jayasankar; Paramasivam, M; Srinivasan, A; Singh, T P

    2004-01-01

    The crystal structure of an acidic phospholipase A(2) from the venom of Echis carinatus (saw-scaled viper; scPLA(2)) has been determined at 2.6 A resolution and refined to a crystallographic R factor of 0.192. Although the overall structure of scPLA(2) is essentially similar to those of other group II acidic PLA(2)s from different species, it shows unique features in several parts. Particularly noteworthy is the C-terminal part, which folds differently to those of other group II PLA(2)s. This part is considered to be responsible for inhibition of the platelet-aggregation activity. The calcium-binding loop is tightly organized with sevenfold coordination. Another striking feature of scPLA(2) is the involvement of Asn79 O(delta1) of a symmetry-related molecule in a coordination linkage with Ca(2+) of the calcium-binding loop. This is the first observation of an internal metal ion participating in an intermolecular interaction. The beta-wing of a molecule is deeply inserted into the hydrophobic channel of another molecule and forms several intermolecular interactions. This results in the formation of an infinite chain of molecules. These chains are stacked in an antiparallel arrangement in the crystals. PMID:14684894

  3. In folio respiratory fluxomics revealed by 13C isotopic labeling and H/D isotope effects highlight the noncyclic nature of the tricarboxylic acid "cycle" in illuminated leaves.

    Tcherkez, Guillaume; Mahé, Aline; Gauthier, Paul; Mauve, Caroline; Gout, Elizabeth; Bligny, Richard; Cornic, Gabriel; Hodges, Michael

    2009-10-01

    While the possible importance of the tricarboxylic acid (TCA) cycle reactions for leaf photosynthesis operation has been recognized, many uncertainties remain on whether TCA cycle biochemistry is similar in the light compared with the dark. It is widely accepted that leaf day respiration and the metabolic commitment to TCA decarboxylation are down-regulated in illuminated leaves. However, the metabolic basis (i.e. the limiting steps involved in such a down-regulation) is not well known. Here, we investigated the in vivo metabolic fluxes of individual reactions of the TCA cycle by developing two isotopic methods, (13)C tracing and fluxomics and the use of H/D isotope effects, with Xanthium strumarium leaves. We provide evidence that the TCA "cycle" does not work in the forward direction like a proper cycle but, rather, operates in both the reverse and forward directions to produce fumarate and glutamate, respectively. Such a functional division of the cycle plausibly reflects the compromise between two contrasted forces: (1) the feedback inhibition by NADH and ATP on TCA enzymes in the light, and (2) the need to provide pH-buffering organic acids and carbon skeletons for nitrate absorption and assimilation. PMID:19675152

  4. Turn on, fade out - methane exchange in a coastal fen over a period of six years after rewetting

    Jurasinski, Gerald; Glatzel, Stephan; Hahn, Juliane; Koch, Stefan; Koch, Marian; Koebsch, Franziska

    2016-04-01

    The rewetting of drained peatlands is widely regarded as an adequate measure for the mitigation of greenhouse gas emissions. Therefore, especially in NE Germany, many peatlands are being rewetted. Our knowledge about greenhouse gas exchange associated with rewetting is mainly based on short-term experiments or space-for-time substitutions. These approaches do not consider the transient character of ecosystem acclimatization to flooding by rewetting. Moreover data in this regard on coastal peatland ecosystems are sparse. Here, we present 7 years of data on CH4-exchange in a coastal fen after rewetting by flooding. On the site „Rodewiese", which is located within the NSG "Hütelmoor und Heiligensee" in the Northeast of Rostock, NE Germany, we have established a long term research observatory addressing atmospheric C-exchange. The site is part of the TERENO network. Since summer 2009 we determine CH4 fluxes with closed chambers distributed widely across the study site and CO2-exchange with eddy covariance as well as ancillary data on vegetation, hydrology, and biogeochemistry. This talk addresses the CH4-exchange over time whereas CO2-exchange data are presented by Koebsch et al. in the same session. Rewetting turned the site from a summer dry fen with mean annual water levels of around -0.08m into a shallow lake with water levels up to 0.60m. In the first year after flooding, we observed a substantial die-back of vegetation, especially in stands of Carex acutiformis. Flooding increased methane release rates to extremely high levels of up to 4.3 t ha‑1 a‑1 for sedge stands and 2.7 t ha‑1 a‑1 on average, which amounts to 75.6 t ha‑1 a‑1 in CO2-equivalents. Thereafter, the averaged annual CH4 emissions decreased asymptotically and where at an average of 0.5 t ha‑1 a‑1 (14 t ha‑1 a‑1 in CO2-equivalents) in 2015. Factoring in the NEE of the growing season (from Eddy measurements) suggests that the system may be slightly above neutral with respect to

  5. Locked Nucleic Acid-Based In Situ Hybridization Reveals miR-7a as a Hypothalamus-Enriched MicroRNA with a Distinct Expression Pattern

    Herzer, S; Silahtaroglu, A; Meister, B

    2012-01-01

    part of the brain that controls vital bodily functions, we employed locked nucleic acid (LNA) - fluorescent in situ hybridization (FISH). The expression pattern of the mature miRNAs miR-7a, miR-7b, miR-137 and miR-153 in mouse brain tissue sections was investigated. Whereas all studied miRNAs were...... shown that miR-7a was preferentially present in small orexigenic neuropeptide Y (NPY)/agouti-related protein (AgRP)-containing-neurons located in the ventromedial aspect of the arcuate nucleus, but not in large pro-opiomelanocortin (POMC)/cocaine- and amphetamine-regulated transcript (CART...... the arcuate nucleus, a subregion with a weak blood-brain barrier, raises the possibility that miR-7a is influenced by circulating hormones and is a regulator of the genes involved in body weight control. © 2012 The Authors. Journal of Neuroendocrinology © 2012 Blackwell Publishing Ltd....

  6. Salicylic and jasmonic acid pathways are necessary for defence against Dickeya solani as revealed by a novel method for Blackleg disease screening of in vitro grown potato.

    Burra, D D; Mühlenbock, P; Andreasson, E

    2015-09-01

    Potato is major crop ensuring food security in Europe, and blackleg disease is increasingly causing losses in yield and during storage. Recently, one blackleg pathogen, Dickeya solani has been shown to be spreading in Northern Europe that causes aggressive disease development. Currently, identification of tolerant commercial potato varieties has been unsuccessful; this is confounded by the complicated etiology of the disease and a strong environmental influence on disease development. There is currently a lack of efficient testing systems. Here, we describe a system for quantification of blackleg symptoms on shoots of sterile in vitro potato plants, which saves time and space compared to greenhouse and existing field assays. We found no evidence for differences in infection between the described in vitro-based screening method and existing greenhouse assays. This system facilitates efficient screening of blackleg disease response of potato plants independent of other microorganisms and variable environmental conditions. We therefore used the in vitro screening method to increase understanding of plant mechanisms involved in blackleg disease development by analysing disease response of hormone- related (salicylic and jasmonic acid) transgenic potato plants. We show that both jasmonic (JA) and salicylic (SA) acid pathways regulate tolerance to blackleg disease in potato, a result unlike previous findings in Arabidopsis defence response to necrotrophic bacteria. We confirm this by showing induction of a SA marker, pathogenesis-related protein 1 (StPR1), and a JA marker, lipoxygenase (StLOX), in Dickeya solani infected in vitro potato plants. We also observed that tubers of transgenic potato plants were more susceptible to soft rot compared to wild type, suggesting a role for SA and JA pathways in general tolerance to Dickeya. PMID:25903921

  7. Módulo expositivo e interactivo sobre fenómenos ópticos

    Dionísio, Rogério

    2009-01-01

    As experiências interactivas são um veículo atractivo de disseminação do conhecimento, em particular no domínio da óptica e das suas aplicações. Este artigo descreve um módulo expositivo e interactivo, destinado a explicar os fenómenos físicos relacionados com a luz. O sistema assemelha-se a uma máquina de jogos, que tem no topo um conjunto de seis experiências e vem equipado com um sistema com informação visual e auditiva. Permite ao utilizador escolher qual a experiência que irá ...

  8. Fenômenos sociais, familiares e psicopatológicos associados ao bullying escolar

    Pereira, Beatriz Oliveira; Lourenço, Lélio Moura; Vieira, Marcel; Senra, Luciana Xavier; Gomes, Daniel; Stephan, Francesca

    2012-01-01

    A violência e a violência familiar, assim como transtornos de ansiedade como a fobia/ansiedade social tem sido apontados como fenômenos que possuem algum tipo de associação seja pela semelhança nas características de manifestação, seja pelo impacto provocado nos âmbitos sociais e de saúde dos indivíduos envolvidos. No que concerne a violência e a violência familiar, vale salientar que os atos de omissão e negligência em detrimento do desenvolvimento pleno e da integridade física e psicológ...

  9. Fenômenos de transporte em sistemas gasosos quaternários reativos

    Silva, Adriano Willian da

    2005-01-01

    Resumo: Este trabalho tem como finalidade apresentar uma análise sobre os efeitos que as reações químicas provocam nos fenômenos de transporte - como por exemplo de massa, momento linear e de energia - em sistemas gasosos quaternários. Para realizar esta análise as reações químicas foram consideradas como sendo processos rápidos, isto _e, processos cuja frequência das interações que resultam em reações químicas possui a mesma ordem de grandeza que a frequência das interações elásticas entre o...

  10. El fenómeno del dopaje desde la perspectiva de las Ciencias Sociales Odile

    Pardo García, Rodrigo; Gonzalez Aja, Teresa Maria; Irureta-Goyena Sánchez, Pilar; Belloni, Eleonora; Zanibelli, Giacomo; Bogunia-Borowska, Małgorzata; Dabrowski, Adam; Carlos COBO CORRALES; Doudou, Dimi Théodore; Angbo-Effie, Odile; Dibi, Trah Daniel; Kra Konan, Gérard Landy; Koffi, Konan Sosthène; Garcia, Carlos; García Arjona, Noemi

    2015-01-01

    En este libro se recoge una selección de las comunicaciones presentadas en el IV Congreso Internacional ‘Deporte, Dopaje y Sociedad’ que se celebró en Madrid del 26 de febrero al 1 de marzo de 2014 y que fue organizado conjuntamente por la Universidad Politécnica de Madrid y la Agencia Española de Protección de la Salud en el Deporte. Los textos están escritos en español, francés e inglés y abordan el estudio del fenómeno del dopaje desde el ámbito especifico de las Ciencias Humanas y Sociale...

  11. Effects of peat-winning on the water environment at a sedge fen ecosystem

    Peatlands are used in agriculture and forestry for vegetational growth and in peat-winning for soil improvement, horticulture production and as fuel. A prerequisite in peatland use is drainage, with influences on water conditions in the peatland and its surroundings. Environmental effects from such peatland use have been investigated at a sedge fen in central Sweden. Groundwater, runoff, water chemistry and stream water biology were studied during almost 14 years. This period started with a virgin undrained peatland, later being drained for forest production and after a period of seven years intensively drained for peat-winning and with peat harvesting going on for another seven years period with hydrological investigations. Results show a lowered groundwater level, increased runoff and both higher concentrations of most elements and higher leaching from the drained peatland. Biomass and number of individuals of the benthic fauna in stream water also increased. 7 refs, 7 figs, 2 tabs

  12. Effects of peat-winning on the water environment at a sedge fen ecosystem

    Peatlands are used in agriculture and forestry for vegetational growth and in peat-winning for soil improvement, horticulture production and as fuel. A prerequisite in peatland use is drainage, with influences on water conditions in the peatland and in its surroundings. Environmental effects from such peatland use have been investigated at a sedge fen in central Sweden. Groundwater, runoff, water chemistry and streamwater biology were studied during almost 14 years. This period started with a virgin undrained peatland, later being drained for forest production and after a period of seven years intensively drained for peat-winning and with peat harvesting going on for another seven year period with hydrological investigations. Results show a lowered groundwater level, increased runoff and both higher concentrations of most elements and higher leaching from the drained peatland. Biomass and number of individuals of the benthic fauna in streamwater also increased. 7 refs

  13. BOREAS TGB-6 Soil Methane Oxidation and Production from NSA BP and Fen Sites

    Deck, Bruce; Wahlen, Martin; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-6) team collected soil methane measurements at several sites in the Southern Study Area (SSA) and Northern Study Area (NSA). This data set contains soil methane consumption (bacterial CH4 oxidation) and associated C-13 fractionation effects in samples that were collected at various sites in 1994 and 1996 from enclosures (chambers). Methane C-13 data in soil gas samples from the NSA Young Jack Pine (YJP) and Old Jack Pine (OJP) sites for 1994 and 1996 are also given. Additional data on the isotopic composition of methane (carbon and hydrogen isotopes) produced in the NSA beaver ponds and fen bog in 1993 and 1994 are given as well. The data are stored in tabular ASCII files.

  14. Climate change effects on lowland stream flood regimes and riparian rich fen vegetation communities in Denmark

    Thodsen, Hans; Baattrup-Pedersen, Annette; Andersen, Hans Estrup;

    2016-01-01

    There is growing awareness that an intensification of the hydrological cycle associated with climate change in many parts of the world will have profound implications for river ecosystem structure and functions. In the present study we link an ensemble of regional climate model projections...... to a hydrological model with the aim to predict climate driven changes in flooding regimes in lowland riparian areas. Our specific aims were to 1) predict effects of climate change on flood frequencies and magnitudes in riparian areas by using an ensemble of six climate models and 2) combine the obtained...... predictions with the distribution of rich fen communities to explore whether these are likely to be subjected to increased flooding by a climate change induced increase in river runoff. We found that all regional climate models in the ensemble showed increases in mean annual runoff and that the increase...

  15. Innovative wetland reclamation design case studies : the Suncor fen and pond 1 marsh

    Daly, C.A. [Suncor Energy, Fort McMurray, AB (Canada); Price, J.; Rezanezhad, F. [Waterloo Univ., ON (Canada); Rochefort, L.; Graf, M. [Laval Univ., Quebec City, PQ (Canada); Russell, B. [BGC Engineering Inc., Calgary, AB (Canada)

    2010-07-01

    Suncor Energy Inc. is an energy company strategically focused in Canada's Athabasca oil sands region. The company has more than 40 years of experience in pioneering commercial development. This presentation discussed reclamation requirements for Suncor Energy. Reclamation objectives that were addressed in this presentation included operating approvals, biodiversity and meeting stakeholder expectations. Several photographs of reclaimed forest areas were shown along with 5 freshwater wetland types and wetland values. Two innovative wetland reclamation design case studies were also presented, described and illustrated, with particular reference to the Suncor fen and pond 1 marsh. It was concluded that future work will involve finalizing site investigation and designs, as well as construction, vegetation, and monitoring. figs.

  16. Efectos ecológicos del fenómeno ENOS en Colombia

    Yesid Carvajal; Henry Jiménez; Hernán Materón

    2014-01-01

    El fenómeno ENOS, tiene un sustancial efecto sobre las variaciones del clima a nivel mundial; por lo tanto, no sorprende que sus efectos tengan un impacto ecológico y socioeconómico fuerte, alterando la seguridad alimentaria de los países a nivel mundial. Ante este panorama, es comprensible que haya despertado el mayor interés mundial, no sólo en los especialistas en meteorología y oceanografía sino también entre biólogos, ecólogos, físicos, matemáticos, agrónomos, hidrólogos, economistas, so...

  17. Reconstruction of annual carbon dynamics and balance for an oligotrophic pine fen

    Alm, J.; Silvola, J.; Aaltonen, H. [Joensuu Univ. (Finland). Dept. of Biology; Talanov, A.; Ikkonen, E. [Karelian Research Centre of Russian Academy of Sciences (Russian Federation). Inst. of Biology; Nykaenen, H.; Martikainen, P.J. [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology

    1996-12-31

    Atmospheric carbon dioxide (CO{sub 2}) is bound by mire vegetation in photosynthesis during the growing season, and is re-released by respiration of plants, soil animals and microorganisms consuming dead organic matter. A small proportion of annual primary production may fall below the water table to anoxic conditions and thus escapes the oxidative decomposition. Also from anoxic peat, carbon is released with clear seasonal and spatial variation as methane (CH{sub 4}.). The rate of carbon accumulation in peat depends on the annual inbalance of plant production and litter decomposition. Exchange of CO{sub 2} and CH{sub 4} between peat, vegetation and the atmosphere thus reflects the dynamics of carbon flows in the ecosystem. Net ecosystem CO{sub 2} exchange (PN), total CO{sub 2} release (RTOT) and CH{sub 4} release (D) from different treeless surfaces of low-sedge Sphagnum papillosum pine fen was studied in eastern Finland. (8 refs.)

  18. Lignina em espumas fenólicas Lignin in phenolic foams 66

    Gil de Carvalho; Elisabete Frollini

    1999-01-01

    A lignina extraída do bagaço de cana de açúcar pode substituir parcialmente o fenol na preparação de resinas fenólicas. Este trabalho aborda a aplicação de pré-polímero resólico, sendo que o fenol foi parcialmente substituído por lignina (25%, massa lignina/massa fenol ), visando a obtenção de material com características de plástico celular. No presente trabalho descreve-se a caracterização das espumas obtidas por microscopia eletrônica de varredura, conteúdo de células fechadas, densidade a...

  19. Turismo religioso: fenómeno social y económico

    Sandra Maribel Tobón Perilla

    2013-12-01

    Full Text Available El turismo religioso, como fenómeno social y económico, ha cobrado interés entre académicos y empresarios por las dinámicas que ha generado en las comunidades receptoras de visitantes. Para los primeros, el interés radica en el estudio de las motivaciones, intereses y necesidades espirituales o culturales que parecen haber despertado los centros religiosos; para los segundos, el impacto económico y las oportunidades de rentas adicionales que generan los visitantes, creando nuevas oportunidades de negocios y fuentes de ingresos y empleo para las comunidades aledañas. Este documento hace una revisión a la bibliografía sobre el tema de turismo religioso en el mundo, para lo cual se consultaron las bases de datos ScienceDirect, Jstor, Ebsco, ProQuest y Google Académico, a fin de rastrear las publicaciones más relevantes y estudios empíricos sobre el tema, haciendo un recorrido desde 1963 hasta 2013. Se concluye que el turismo religioso es un fenómeno que tiene su antecedente en el peregrinaje a centros religiosos, pero donde además de las motivaciones, netamente religiosas –ofrecer un sacrificio, obtener un beneficio divino o expiar pecados–, existe un interés cultural, en términos de conocer centros históricos o profundizar sobre las raíces de un credo religioso. Adicionalmente, se observa cómo el turismo religioso se ha convertido en un motor de desarrollo económico de las ciudades receptoras de viajeros a sitios religioso.

  20. Lignina em espumas fenólicas Lignin in phenolic foams 66

    Gil de Carvalho

    1999-01-01

    Full Text Available A lignina extraída do bagaço de cana de açúcar pode substituir parcialmente o fenol na preparação de resinas fenólicas. Este trabalho aborda a aplicação de pré-polímero resólico, sendo que o fenol foi parcialmente substituído por lignina (25%, massa lignina/massa fenol , visando a obtenção de material com características de plástico celular. No presente trabalho descreve-se a caracterização das espumas obtidas por microscopia eletrônica de varredura, conteúdo de células fechadas, densidade aparente, resistência à compressão e dureza. A espuma lignina-fenol-formaldeído apresentou propriedades mecânicas consideravelmente superiores àquelas da espuma fenólica convencional, caracterizando-se como uma espuma estrutural, com características de isolante térmico.Lignin can be recovered from sugar cane bagasse, which is largely available in Brazil, as a residue from sugar mills. This work presents a new application for lignin-phenol formaldehyde polymers in cellular materials. The foams obtained were characterized by scanning electron microscopy, open cell content, apparent density, compressive strength, hardness. The lignin-phenol-formaldehyde foam presents a thermal insulating characteristics combined with remarkable mechanical properties, which allows its application as structural-thermal insulation foam

  1. Nutrient limitation and nutrient-driven shifts in plant species composition in a species-rich fen meadow

    Hoek, D. van der; Mierlo, A. van; Groenendael, J.M. van

    2004-01-01

    Question: We studied the development and persistence of the effects of nutrient pulses on biomass production and species composition in a fen meadow. Location: Nature reserve, central Netherlands, 5 m a.s.l. Methods: Single pulse fertilization with N and P in a factorial design on an undrained centr

  2. Distinct abscisic acid signaling pathways for modulation of guard cell versus mesophyll cell potassium channels revealed by expression studies in Xenopus laevis oocytes

    Sutton, F.; Paul, S. S.; Wang, X. Q.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    2000-01-01

    Regulation of guard cell ion transport by abscisic acid (ABA) and in particular ABA inhibition of a guard cell inward K(+) current (I(Kin)) is well documented. However, little is known concerning ABA effects on ion transport in other plant cell types. Here we applied patch clamp techniques to mesophyll cell protoplasts of fava bean (Vicia faba cv Long Pod) plants and demonstrated ABA inhibition of an outward K(+) current (I(Kout)). When mesophyll cell protoplast mRNA (mesophyll mRNA) was expressed in Xenopus laevis oocytes, I(Kout) was generated that displayed similar properties to I(Kout) observed from direct analysis of mesophyll cell protoplasts. I(Kout) expressed by mesophyll mRNA-injected oocytes was inhibited by ABA, indicating that the ABA signal transduction pathway observed in mesophyll cells was preserved in the frog oocytes. Co-injection of oocytes with guard cell protoplast mRNA and cRNA for KAT1, an inward K(+) channel expressed in guard cells, resulted in I(Kin) that was similarly inhibited by ABA. However, oocytes co-injected with mesophyll mRNA and KAT1 cRNA produced I(Kin) that was not inhibited by ABA. These results demonstrate that the mesophyll-encoded signaling mechanism could not substitute for the guard cell pathway. These findings indicate that mesophyll cells and guard cells use distinct and different receptor types and/or signal transduction pathways in ABA regulation of K(+) channels.

  3. Cell-free production of integral membrane aspartic acid proteases reveals zinc-dependent methyltransferase activity of the Pseudomonas aeruginosa prepilin peptidase PilD

    Aly, Khaled A; Beebe, Emily T; Chan, Chi H; Goren, Michael A; Sepúlveda, Carolina; Makino, Shin-ichi; Fox, Brian G; Forest, Katrina T

    2013-01-01

    Integral membrane aspartic acid proteases are receiving growing recognition for their fundamental roles in cellular physiology of eukaryotes and prokaryotes, and may be medically important pharmaceutical targets. The Gram-negative Pseudomonas aeruginosa PilD and the archaeal Methanococcus voltae FlaK were synthesized in the presence of unilamellar liposomes in a cell-free translation system. Cosynthesis of PilD with its full-length substrate, PilA, or of FlaK with its full-length substrate, FlaB2, led to complete cleavage of the substrate signal peptides. Scaled-up synthesis of PilD, followed by solubilization in dodecyl-β-d-maltoside and chromatography, led to a pure enzyme that retained both of its known biochemical activities: cleavage of the PilA signal peptide and S-adenosyl methionine-dependent methylation of the mature pilin. X-ray fluorescence scans show for the first time that PilD is a zinc-binding protein. Zinc is required for the N-terminal methylation of the mature pilin, but not for signal peptide cleavage. Taken together, our work identifies the P. aeruginosa prepilin peptidase PilD as a zinc-dependent N-methyltransferase and provides a new platform for large-scale synthesis of PilD and other integral membrane proteases important for basic microbial physiology and virulence. PMID:23255525

  4. The hsp 16 Gene of the Probiotic Lactobacillus acidophilus Is Differently Regulated by Salt, High Temperature and Acidic Stresses, as Revealed by Reverse Transcription Quantitative PCR (qRT-PCR Analysis

    Daniela Fiocco

    2011-08-01

    Full Text Available Small heat shock proteins (sHsps are ubiquitous conserved chaperone-like proteins involved in cellular proteins protection under stressful conditions. In this study, a reverse transcription quantitative PCR (RT-qPCR procedure was developed and used to quantify the transcript level of a small heat shock gene (shs in the probiotic bacterium Lactobacillus acidophilus NCFM, under stress conditions such as heat (45 °C and 53 °C, bile (0.3% w/v, hyperosmosis (1 M and 2.5 M NaCl, and low pH value (pH 4. The shs gene of L. acidophilus NCFM was induced by salt, high temperature and acidic stress, while repression was observed upon bile stress. Analysis of the 5' noncoding region of the hsp16 gene reveals the presence of an inverted repeat (IR sequence (TTAGCACTC-N9-GAGTGCTAA homologue to the controlling IR of chaperone expression (CIRCE elements found in the upstream regulatory region of Gram-positive heat shock operons, suggesting that the hsp16 gene of L. acidophilus might be transcriptionally controlled by HrcA. In addition, the alignment of several small heat shock proteins identified so far in lactic acid bacteria, reveals that the Hsp16 of L. acidophilus exhibits a strong evolutionary relationship with members of the Lactobacillus acidophilus group.

  5. The hsp 16 gene of the probiotic Lactobacillus acidophilus is differently regulated by salt, high temperature and acidic stresses, as revealed by reverse transcription quantitative PCR (qRT-PCR) analysis.

    Capozzi, Vittorio; Arena, Mattia Pia; Crisetti, Elisabetta; Spano, Giuseppe; Fiocco, Daniela

    2011-01-01

    Small heat shock proteins (sHsps) are ubiquitous conserved chaperone-like proteins involved in cellular proteins protection under stressful conditions. In this study, a reverse transcription quantitative PCR (RT-qPCR) procedure was developed and used to quantify the transcript level of a small heat shock gene (shs) in the probiotic bacterium Lactobacillus acidophilus NCFM, under stress conditions such as heat (45 °C and 53 °C), bile (0.3% w/v), hyperosmosis (1 M and 2.5 M NaCl), and low pH value (pH 4). The shs gene of L. acidophilus NCFM was induced by salt, high temperature and acidic stress, while repression was observed upon bile stress. Analysis of the 5' noncoding region of the hsp16 gene reveals the presence of an inverted repeat (IR) sequence (TTAGCACTC-N9-GAGTGCTAA) homologue to the controlling IR of chaperone expression (CIRCE) elements found in the upstream regulatory region of Gram-positive heat shock operons, suggesting that the hsp16 gene of L. acidophilus might be transcriptionally controlled by HrcA. In addition, the alignment of several small heat shock proteins identified so far in lactic acid bacteria, reveals that the Hsp16 of L. acidophilus exhibits a strong evolutionary relationship with members of the Lactobacillus acidophilus group. PMID:21954366

  6. Structures of the first representatives of Pfam family PF06684 (DUF1185) reveal a novel variant of the Bacillus chorismate mutase fold and suggest a role in amino-acid metabolism

    Structures of the first representatives of PF06684 (DUF1185) reveal a Bacillus chorismate mutase-like fold with a potential role in amino-acid synthesis. The crystal structures of BB2672 and SPO0826 were determined to resolutions of 1.7 and 2.1 Å by single-wavelength anomalous dispersion and multiple-wavelength anomalous dispersion, respectively, using the semi-automated high-throughput pipeline of the Joint Center for Structural Genomics (JCSG) as part of the NIGMS Protein Structure Initiative (PSI). These proteins are the first structural representatives of the PF06684 (DUF1185) Pfam family. Structural analysis revealed that both structures adopt a variant of the Bacillus chorismate mutase fold (BCM). The biological unit of both proteins is a hexamer and analysis of homologs indicates that the oligomer interface residues are highly conserved. The conformation of the critical regions for oligomerization appears to be dependent on pH or salt concentration, suggesting that this protein might be subject to environmental regulation. Structural similarities to BCM and genome-context analysis suggest a function in amino-acid synthesis

  7. Label-Free LC-MS Profiling of Skeletal Muscle Reveals Heart-Type Fatty Acid Binding Protein as a Candidate Biomarker of Aerobic Capacity

    Zulezwan A. Malik

    2013-12-01

    Full Text Available Two-dimensional gel electrophoresis provides robust comparative analysis of skeletal muscle, but this technique is laborious and limited by its inability to resolve all proteins. In contrast, orthogonal separation by SDS-PAGE and reverse-phase liquid chromatography (RPLC coupled to mass spectrometry (MS affords deep mining of the muscle proteome, but differential analysis between samples is challenging due to the greater level of fractionation and the complexities of quantifying proteins based on the abundances of their tryptic peptides. Here we report simple, semi-automated and time efficient (i.e., 3 h per sample proteome profiling of skeletal muscle by 1-dimensional RPLC electrospray ionisation tandem MS. Solei were analysed from rats (n = 5, in each group bred as either high- or low-capacity runners (HCR and LCR, respectively that exhibited a 6.4-fold difference (1,625 ± 112 m vs. 252 ± 43 m, p < 0.0001 in running capacity during a standardized treadmill test. Soluble muscle proteins were extracted, digested with trypsin and individual biological replicates (50 ng of tryptic peptides subjected to LC-MS profiling. Proteins were identified by triplicate LC-MS/MS analysis of a pooled sample of each biological replicate. Differential expression profiling was performed on relative abundances (RA of parent ions, which spanned three orders of magnitude. In total, 207 proteins were analysed, which encompassed almost all enzymes of the major metabolic pathways in skeletal muscle. The most abundant protein detected was type I myosin heavy chain (RA = 5,843 ± 897 and the least abundant protein detected was heat shock 70 kDa protein (RA = 2 ± 0.5. Sixteen proteins were significantly (p < 0.05 more abundant in HCR muscle and hierarchal clustering of the profiling data highlighted two protein subgroups, which encompassed proteins associated with either the respiratory chain or fatty acid oxidation. Heart-type fatty acid binding protein (FABPH was 1

  8. The hydrological and geochemical isolation of a freshwater bog within a saline fen in north-eastern Alberta

    S.J. Scarlett

    2013-10-01

    Full Text Available In the oil sands development region near Fort McMurray, Alberta, wetlands cover ~62 % of the landscape, and ~95 % of these wetlands are peatlands. A saline fen was studied as a reference site for peatland reclamation. Despite highly saline conditions, a freshwater bog was observed in the path of local saline groundwater flow. The purpose of this study was to identify the hydrological controls that have allowed the development and persistence of a bog in this setting. The presence of bog vegetation and its dilute water chemistry suggest that saline groundwater from the fen rarely enters the bog, which functions predominantly as a groundwater recharge system. Chloride (Cl– and sodium (Na+ were the dominant ions in fen water, with concentrations averaging 5394 and 2307 mg L-1, respectively, while the concentrations in bog water were 5 and 4 mg L-1, respectively. These concentrations were reflected by salinity and electrical conductivity measurements, which in the fen averaged 9.3 ppt, and 15.8 mS cm-1, respectively, and in the bog averaged 0.1 ppt and 0.3 mS cm-1, respectively. A small ridge in the mineral substratum was found at the fen–bog margin, which created a persistent groundwater mound. Under the dry conditions experienced in early summer, groundwater flow was directed away from the bog at a rate of 14.6 mm day-1. The convex water table at the fen-bog margin impeded flow of saline water into the bog and instead directed it around the bog margin. However, the groundwater mound was eliminated during flooding in autumn, when the horizontal hydraulic gradient across the margin became negligible, suggesting the possibility of saline water ingress into the bog under these conditions.

  9. Orientation Preferences of Backbone Secondary Amide Functional Groups in Peptide Nucleic Acid Complexes: Quantum Chemical Calculations Reveal an Intrinsic Preference of Cationic D-Amino Acid-Based Chiral PNA Analogues for the P-form

    Smith, Jeremy C [ORNL; Topham, Christopher [University of Heidelberg

    2007-01-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like base pair stacking. Quantum chemical calculations on the binding of a water molecule to an O2 base atom in glycine-based PNA thymine dimers indicate that junctions modeled with P-form backbone conformations are lower in energy than a dimer comprising the predominant conformation observed in A-like helices. It is further shown in model systems that PNA analogs based on D-lysine are better able to preorganize in a conformation exclusive to P-form helices than is glycine-based PNA. An intrinsic preference for this conformation is also exhibited by positively charged chiral PNA dimers carrying 3-amino-D-alanine or 4-aza-D-leucine residue units that provide for additional rigidity by side-chain hydrogen bonding to the backbone carbonyl oxygen. Structural modifications stabilizing P-form helices may obviate the need for large heterocycles to target DNA pyrimidine bases via PNADNA-PNA triplex formation. Quantum chemical modeling methods are used to propose candidate PNA Hoogsteen strand designs.

  10. Orientation preferences of backbone secondary amide functional groups in peptide nucleic acid complexes: quantum chemical calculations reveal an intrinsic preference of cationic D-amino acid-based chiral PNA analogues for the P-form.

    Topham, Christopher M; Smith, Jeremy C

    2007-02-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like basepair stacking. Quantum chemical calculations on the binding of a water molecule to an O2 base atom in glycine-based PNA thymine dimers indicate that junctions modeled with P-form backbone conformations are lower in energy than a dimer comprising the predominant conformation observed in A-like helices. It is further shown in model systems that PNA analogs based on D-lysine are better able to preorganize in a conformation exclusive to P-form helices than is glycine-based PNA. An intrinsic preference for this conformation is also exhibited by positively charged chiral PNA dimers carrying 3-amino-D-alanine or 4-aza-D-leucine residue units that provide for additional rigidity by side-chain hydrogen bonding to the backbone carbonyl oxygen. Structural modifications stabilizing P-form helices may obviate the need for large heterocycles to target DNA pyrimidine bases via PNA.DNA-PNA triplex formation. Quantum chemical modeling methods are used to propose candidate PNA Hoogsteen strand designs. PMID:17071666

  11. Mathematics revealed

    Berman, Elizabeth

    1979-01-01

    Mathematics Revealed focuses on the principles, processes, operations, and exercises in mathematics.The book first offers information on whole numbers, fractions, and decimals and percents. Discussions focus on measuring length, percent, decimals, numbers as products, addition and subtraction of fractions, mixed numbers and ratios, division of fractions, addition, subtraction, multiplication, and division. The text then examines positive and negative numbers and powers and computation. Topics include division and averages, multiplication, ratios, and measurements, scientific notation and estim

  12. Revealed Attention

    Masatlioglu, Yusufcan; NAKAJIMA, Daisuke; Ozbay, Erkut Y

    2012-01-01

    The standard revealed preference argument relies on an implicit assumption that a decision maker considers all feasible alternatives. The marketing and psychology literatures, however, provide wellestablished evidence that consumers do not consider all brands in a given market before making a purchase (Limited Attention). In this paper, we illustrate how one can deduce both the decision maker's preference and the alternatives to which she pays attention and inattention from the observed behav...

  13. Revealed Attention

    Yusufcan Masatlioglu; Daisuke Nakajima; Ozbay, Erkut Y

    2012-01-01

    The standard revealed preference argument relies on an implicit assumption that a decision maker considers all feasible alternatives. The marketing and psychology literatures, however, provide well-established evidence that consumers do not consider all brands in a given market before making a purchase (Limited Attention). In this paper, we illustrate how one can deduce both the decision maker's preference and the alternatives to which she pays attention and inattention from the observed beha...

  14. Molecular interactions between the specialist herbivore Manduca sexta (lepidoptera, sphingidae) and its natural host Nicotiana attenuata. VI. Microarray analysis reveals that most herbivore-specific transcriptional changes are mediated by fatty acid-amino acid conjugates.

    Halitschke, Rayko; Gase, Klaus; Hui, Dequan; Schmidt, Dominik D; Baldwin, Ian T

    2003-04-01

    Evidence is accumulating that insect-specific plant responses are mediated by constituents in the oral secretions and regurgitants (R) of herbivores, however the relative importance of the different potentially active constituents remains unclear. Fatty acid-amino acid conjugates (FACs) are found in the R of many insect herbivores and have been shown to be necessary and sufficient to elicit a set of herbivore-specific responses when the native tobacco plant Nicotiana attenuata is attacked by the tobacco hornworm, Manduca sexta. Attack by this specialist herbivore results in a large transcriptional reorganization in N. attenuata, and 161 genes have been cloned from previous cDNA differential display-polymerase chain reaction and subtractive hybridization with magnetic beads analysis. cDNAs of these genes, in addition to those of 73 new R-responsive genes identified by cDNA-amplified fragment-length polymorphism display of R-elicited plants, were spotted on polyepoxide coated glass slides to create microarrays highly enriched in Manduca spp.- and R-induced genes. With these microarrays, we compare transcriptional responses in N. attenuata treated with R from the two most damaging lepidopteran herbivores of this plant in nature, M. sexta and Manduca quinquemaculata, which have very similar FAC compositions in their R, and with the two most abundant FACs in Manduca spp. R. More than 68% of the genes up- and down-regulated by M. sexta R were similarly regulated by M. quinquemaculata R. A majority of genes up-regulated (64%) and down-regulated (49%) by M. sexta R were similarly regulated by treatment with the two FACs. In contrast, few genes showed similar transcriptional changes after H(2)O(2)- and R-treatment. These results demonstrate that the two most abundant FACs in Manduca spp. R can account for the majority of Manduca spp.-induced alterations of the wound response of N. attenuata. PMID:12692348

  15. Feminización del fenómeno migratorio ecuatoriano

    Jorge Moreno Egas

    2009-12-01

    Full Text Available La crítica situación económica y política del Ecuador en la última década del XX fue la coyuntura que agudizó el fenómeno migratorio presente desde mediados de ese siglo. América Latina, Norte América y en los últimos tiempos Europa, particularmente España e Italia son los lugares de destino de los ecuatorianos. Este hecho se caracteriza por ser amplio y diverso. Los migrantes provienen de todas las clases sociales, es multigeneracional y particularmente femenino. Los efectos de la crisis y situaciones particulares de violencia y marginación han obligado a las mujeres a buscar alternativas de trabajo fuera del país. La feminización del fenómeno migratorio, dentro o fuera de la legalidad, más allá de su lado bueno, - remesas para la familia que queda a tras, éxitos personales en los lugares de acogida y la perspectiva de reunificación de la familia -, coloca a las migrantes en situaciones de vulnerabilidad, origina rupturas familiares y pone en riesgo la seguridad de los niños por privárseles del papel protagónico que las madres cumplen en su crianza.___________________ABSTRACT:Ecuador’s critical economic and political situation during the last decade of the Twentieth Century was the trend that worsened the emigration phenomenon present from the middle of the century. Latin America, North America and, lately, Europe, particularly Spain and Italy, are the destinations for Ecuadorians. This fact is characterized by being broad and diverse. Emigrants come from all social classes, are multi-generational and particularly female. The effects of the crisis and the specific situations of violence and marginalization have forced women to seek options for work outside the country. The feminization of the emigration phenomenon inside or outside the law other than its good side – remittances to the family that stayed behind, personal success in the places where they are received and the perspective of reuniting with family

  16. Compuestos fenólicos del olivo (Olea europea

    Maestro-Durán, R.

    1994-08-01

    Full Text Available Certain plant properties, such as the colour, the nutritional value, the resistance to microorganisms, the pharmacologic effects and the organoleptic character, are due to the phenolic compounds. It is interesting the study of phenolic compounds from olive because they:

    -Inhibit Gram+ microorganisms, such as Lactobacillus, which are involved in the fermentation of the olive fruit. -Inhibit the activity of cellulases and other enzymes. -Contribute to the stability and organoleptic character of virgin olive oil. -Inhibit the effect of microorganisms involved in the anaerobic depuration of vegetation water. Thus, the phenolic compounds are the major bothersome contaminants of these wastewater. -Have pharmacologic properties (to reduce blood pressure levels. -Are natural antioxidants.

    In the present review we describe the composition of the phenolic compounds from the olive fruit (pulp and seed, the olive oil and its by-products (vegetation water and rape and the olive leaves.

    Ciertas propiedades de las plantas, como el color, valor nutricional, autoprotección contra microorganismos, propiedades farmacológicas o caracteres organolépticos, son debidas a los compuestos fenólicos. Su estudio, en el caso del olivo, es de gran interés por diversas razones:

    -Por su carácter antibiótico, los fenoles de la aceituna inhiben los microorganismos Gram+, como Lactobacillus, necesarios para la fermentación de aceitunas de mesa. -Inhiben la acción de las celulasas y otras enzimas. -Son los responsables de la alta estabilidad de los aceites vírgenes de oliva, así como de alguno de sus caracteres organolépticos. -Inhiben la acción de los microorganismos responsables de la depuración anaerobia de los alpechines y son las sustancias contaminantes de estas aguas residuales cuya degradación para eliminar la DQO presenta más dificultades. -Tienen propiedades

  17. Oral tolerance El fenómeno de la tolerancia oral

    Martín Correa

    1989-03-01

    Full Text Available

    The phenomenon of decreased systemic Immune response to orally administered antigens is known as oral tolerance (OT. Though It was anecdotically described many years ago, the mechanisms and potential applications of OT are still mostly speculative. Specificity and thymus-dependence are among its most remarkable features. OT is manifested by the absence of systemic antibodies, of delayed type hypersensitivity and of proliferate responses toward the specific antigen. Potential mechanisms of OT have been grouped in three types, namely: Immunologic, gastrointestinal and individual. The most Important of the immunologic mechanisms might be the existence of counter-suppressive cells but their intimate functioning has not been thoroughly elucidated. The study of OT opens a wide research field with Implications for the immunoprophylaxis and Immunotherapy of many diseases.

    Se da el nombre de tolerancia oral al estado de respuesta inmune sistémica disminuida a antígenos administrados por la vía oral. Si bien el fenómeno fue descrito anecdóticamente desde hace muchos años, sus mecanismos y posibles aplicaciones todavía son materia de especulación. Entre sus características notables se destacan la especificidad y la timodependencia. La tolerancia se manifiesta por ausencia de anticuerpos sistémicos, de hipersensibilidad de tipo retardado y de respuestas proliferativas al antígeno específico. Los posibles mecanismos responsables de la tolerancia oral se han agrupado en tres tipos: inmunológicos, gastrointestinales e individuales. En cuanto a los inmunológicos, el más importante podría ser la existencia de las células contrasupresoras, pero los mecanismos íntimos de funcionamiento de éstas no están completamente elaborados. El estudio del fenómeno de la tolerancia oral abre un amplio campo

  18. Comparison of site calibration and cross calibration of Gao Fen (GF)-1 Wide Field of View (WFV)

    Liu, Li; Xu, Wen; Lu, Shuning; Fu, Qiaoyan; Pan, Zhiqiang; Shi, Tingting

    2015-10-01

    The Wide Field of View (WFV) is one of the key instruments for China's high resolution earth observing system, operating on the Gao Fen-1 (GF-1) satellite which was launched on April 26, 2013. WFV has 4 typical reflective solar bands from 0.45-0.89 μm with 16m nadir spatial resolution. Because of GF-1's lacking in onboard calibrators, on-orbit radiometric calibration is mainly relies on site calibration. The reflectance-based method of site calibration has been used for the absolute radiometric calibration of the GF-1 WFV on June 26th, 2013 and August 3rd, 2014. The reflectance-based method relies on ground-based measurements of the surface reflectance and atmospheric conditions at Dunhuang test site nearly coincident with the imaging of the test site by the WFV. Site calibration is a time consuming and hard sledding method, which is also difficult to reveal or adequately correct for the deficiency of instrument calibration by its own calibration subsystem. Cross-calibration can be a powerful method to remedy the insufficient of the site calibration. Terra Moderate Resolution Imaging Spectroradiometer (MODIS) with its high accuracy onboard calibration system has been selected as reference sensor. Cross calibration between GF-1/WFV and Terra/MODIS are based on the near-simultaneous and cloud-free image pairs over Dunhuang test site on the same day with site calibration. Spectral band adjustment factors (SBAF) for the cross calibration are determined by SRF, solar zenith and azimuth angle, sensors' zenith and azimuth angle and a typical reflectance spectrum over the Dunhuang test site obtained by in-situ measurements. The percentage difference between the site calibrations is within 5% which reflects that the GF-1/WFV is stable after the launch and the reflectance-based method itself is reliable. The comparison of site calibration and cross calibration shows that site calibration has higher accuracy than the cross calibration, the cross calibration is affected by

  19. Electronic Structures of the [Fe(N2)(SiP(iPr)3)](+1/0/-1) Electron Transfer Series: A Counterintuitive Correlation between Isomer Shifts and Oxidation States.

    Ye, Shengfa; Bill, Eckhard; Neese, Frank

    2016-04-01

    The electronic structure analysis of the low-spin iron(II/I/0) complexes [Fe(N2)(SiP(iPr)3)](+/0/-) (SiP(iPr)3 = [Si(o-C6H4P(i)Pr2)3](-)) recently published by J. Peters et al. (Nature Chem. 2010, 2, 558-565) reveals that the redox processes stringing this electron transfer series are best viewed as metal-centered reductions, i.e. Fe(II)N2(0) → Fe(I)N2(0) → Fe(0)N2(0). Superficially, the interpretation seems to be incompatible with the Mössbauer measurement, because the observed isomer shifts are more negative for the lower oxidation states, whereas typically iron-based reduction tends to increase the isomer shift. To rationalize the experimental findings, we analyzed the contributions from the 1s to 4s orbitals to the charge density at the Mössbauer nucleus and found that the positive correlation between the isomer shift and the oxidation state results from an unusual shrinking of the Fe-N2 bond upon reduction due to enhanced N2 to Fe π-backbonding. The other effects of reduction arising from shielding of the nuclear potential, decreasing covalency, and changes in the 4s population would induce the usual negative correlation. The structure distortion dictates the radial distribution of the 4s orbital and the charge density at the nucleus such that a virtually linear relationship between the isomer shift and the Fe-N2 distance could be identified for this series. PMID:26966915

  20. Water level, vegetation composition, and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    Minke, Merten; Augustin, Jürgen; Burlo, Andrei; Yarmashuk, Tatsiana; Chuvashova, Hanna; Thiele, Annett; Freibauer, Annette; Tikhonov, Vitalij; Hoffmann, Mathias

    2016-07-01

    Peat extraction leaves a land surface with a strong relief of deep cutover areas and higher ridges. Rewetting inundates the deep parts, while less deeply extracted zones remain at or above the water level. In temperate fens the flooded areas are colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis dependent on water depth. Reeds of Typha and Phragmites are reported as large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. Here, we analyze the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse gas emissions were measured campaign-wise with manual chambers every 2 to 4 weeks for 2 years and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions generally increased with net ecosystem CO2 uptake. Mesotrophic small sedge reeds with water table around the land surface were small GHG sources in the range of 2.3 to 4.2 t CO2 eq. ha-1 yr-1. Eutrophic tall sedge - Typha latifolia reeds on newly formed floating mats were substantial net GHG emitters in the range of 25.1 to 39.1 t CO2 eq. ha-1 yr. They represent transient vegetation stages. Phragmites reeds ranged between -1.7 to 4.2 t CO2 eq. ha-1 yr-1 with an overall mean GHG emission of 1.3 t CO2 eq. ha-1 yr-1. The annual CO2 balance was best explained by vegetation biomass, which includes the role of vegetation composition and species. Methane emissions were obviously driven by biological activity of vegetation and soil organisms. Shallow flooding of cutover temperate fens is a suitable measure to arrive at low GHG emissions. Phragmites australis establishment should be promoted in deeper flooded areas and will lead to moderate, but

  1. Fenólicos totais e capacidade antioxidante in vitro de polpas de frutos tropicais Total phenolics and antioxidant capacity "in vitro" of tropical fruit pulps

    Luanne Morais Vieira

    2011-09-01

    Full Text Available O consumo de frutos e suas polpas tem sido muito recomendado por seu valor nutricional, alto teor de fibras, vitamina C e carotenoides. Trabalhos recentes têm apontado esses alimentos como fontes de compostos fenólicos com ação antioxidante, portanto sequestradores de radicais livres, com ação protetora contra o surgimento e/ou desenvolvimento de processos degenerativos que conduzem a doenças crônicas não transmissíveis. Devido à crescente comercialização e consumo de polpas de frutas no Brasil, especialmente na cidade de Teresina-Piauí, este trabalho selecionou um grupo de polpas de frutos de elevado consumo local para avaliação do teor de fenólicos totais e da atividade antioxidante in vitro pelo método de captura de radicais livres: DPPH (radical 1,1-diphenil-2-picrilhydrazil e ABTS (radical 2,2'azinobis(3-ethylbenzthiazoline-6-sulfonic acid. Os frutos selecionados foram: Acerola (Malpighia emarginata DC., Bacuri (Platonia insignis Mart., Cajá (Spondias mombin L., Caju (Anacardium occidentale, Goiaba(Psidium guajava e Tamarindo (Tamarindus indica L.. Os teores de fenólicos totais encontrados nas polpascongeladas destes frutos exibiram quantidades relevantes de polifenóis, destacando-se a polpa de acerola com 835,25 ± 32,44 e 449,63 ± 10,24 mg /100g nos extratos aquosos e hidroalcoólicos, respectivamente, seguido pela polpa de caju com 201,61 ± 19,15 e 165,07 ± 4,10 mg /100g. As polpas de bacuri e tamarindo foram as que apresentaram os menores teores de fenólicos totais. Com relação à atividade antioxidante in vitro, os melhores resultados foram encontrados para os extratos aquosos e hidroalcoólicos das polpas de acerola, caju e goiaba. A capacidade antioxidante destas polpas (EC50 em µg/mL variou de 24,42 a 413,36 e de 1,74 a 259,18 para os extratos aquosos e hidroalcoólicos, respectivamente. Utilizando o radical ABTS, a atividade antioxidante para essas mesmas polpas de frutas apresentou valores TEAC que

  2. Atividade antioxidante e teor de fenólicos totais em hortaliças orgânicas e convencionais Antioxidant activity and phenolic content in organic and conventional vegetables

    Kettelin Aparecida Arbos

    2010-06-01

    Full Text Available Considerando que os consumidores estão mais conscientes com a sua saúde e mais preocupados com as condições ambientais, verifica-se uma crescente demanda por alimentos orgânicos. O objetivo deste estudo foi comparar a atividade antioxidante e o teor de fenólicos totais entre alface, rúcula e almeirão de cultivos orgânico e convencional, plantados em uma mesma horta. A atividade antioxidante dos extratos metanólicos das hortaliças foi determinada através do ensaio do DPPH. O teor de fenólicos totais foi obtido espectrofotometricamente de acordo com o método de Folin-Ciocalteu e calculado como equivalente de ácido gálico. A atividade antioxidante contra o radical livre DPPH foi: rúcula orgânica > almeirão orgânico > alface orgânica > rúcula convencional > almeirão convencional > alface convencional. O teor de fenólicos totais foi superior nos vegetais orgânicos. Os resultados deste estudo sugerem que as hortaliças orgânicas podem ser uma importante fonte de antioxidantes naturais e de compostos fenólicos e, portanto, seu consumo deve ser estimulado.Considering that consumers are becoming more conscious of their health and more concerned with environmental conditions, there has been an increasing demand for organic foods. The aim of this study was to compare the antioxidant activity and determine the total phenolic content of organic and conventional cultivations of lettuce, arugula, and chicory grown in the same vegetable garden. The antioxidant activity of the methanol extracts of these leaf vegetables wasdetermined using DPPH free radical scavenging assay. The total phenolic content in the extracts was determined spectrometrically according to the Folin-Ciocalteu method and calculated as equivalent of gallic acid. The antioxidant activity against the DPPH free radical was: organic arugula> organic chicory > organic lettuce > conventional arugula > conventional chicory > conventional lettuce. The total phenolic content

  3. El sesgo de subconfianza como fenómeno de dominio específico

    Guillermo Macbeth

    2009-01-01

    Full Text Available Se define la calibración o confianza como la coincidencia o discrepancia entre el éxito subjetivo y el éxito objetivo que presenta una persona en la realización de una colecci ón de tareas. Las discrepancias entre uno y otro generan distorsiones conocidas como sesgos de la calibración. Cuando el éxito subjetivo predomina sobre el éxito objetivo se observa el sesgo de sobreconfianza. En el caso contrario, se observa el sesgo de subconfianza. Se presenta un estudio experimental que intenta decidir si el dominio es relevante para la disolución del sesgo de subconfianza. Los resultados indican que el domino es efectivamente relevante para reducir y eliminar esta distorsi ón del pensamiento humano. La exposición de los participantes a un modelo metacognitivo de calibración de domino específico logró disolver el sesgo. Cuando se empleó un modelo de dominio no específico, en cambio, el sesgo no se disolvió sino que se invirtió produciendo el sesgo de sobreconfianza. Se concluye que el sesgo de subconfianza es un fenómeno metacognitivo de dominio específico.

  4. El patrimonio como fenómeno socio-cultural y su contextualización

    Nurys de los Angeles Valcárcel Leyva

    2011-01-01

    Full Text Available El humanista del presente requiere sólidas bases académicas, que le permitan desarrollar la práctica de enfrentamiento a la aculturación neoliberal. Se ofrecen análisis y valoraciones en torno al patrimonio, los cuales se consideran referentes que fundamentan científicamente la necesidad del sujeto cultural de defender su pertenencia identitaria. El patrimonio se aborda como fenómeno que se desarrolla a instancias del proceso de relaciones entre sociedad y cultura, como resultado de la contradicción conservaciónrenovación inherente al desarrollo humano. Las formulaciones conceptuales y de reconceptualización, se presentan desde la apoyatura científica que ofrecen ciencias particulares como la filosofía, antropología, sociología y otras, éstas contribuyen a la interpretación y análisis crítico-reflexivo de la relación patrimonioidentidad- contexto sociocultural, a partir del dimensionamiento ontológico, gnoseológico y axiológico de los valorespatrimoniales, todo lo cual aporta recursos cognoscitivos y axiológicos válidos para favorecer la formación y desarrollo de un sujeto cultural que refrende su pertenencia identitaria.

  5. Carbonaceous thin film coating with Fe-N4 site for enhancement of dioxovanadium ion reduction

    Maruyama, Jun; Hasegawa, Takahiro; Iwasaki, Satoshi; Fukuhara, Tomoko; Orikasa, Yuki; Uchimoto, Yoshiharu

    2016-08-01

    It has been found that carbonaceous materials containing a transition metal coordinated by 4 nitrogens in the square-planar configuration (metal-N4 site) on the surface possessed a catalytic activity for various electrochemical reactions related to energy conversion and storage; i.e., oxygen reduction, hydrogen evolution, and quite recently, the electrode reactions in vanadium redox flow batteries (VRFB). The catalyst for the VRFB positive electrode discharge reaction, i.e., the dioxovanadium ion reduction, was formed by coating the surface of cup-stack carbon nanotubes with a carbonaceous thin film with the Fe-N4 site generated by the sublimation, deposition, and pyrolysis of iron phthalocyanine. In this study, the influence of the physical properties of the catalyst on the electrochemical reactions was investigated to optimize the coating. With an increase in the coating, the specific surface area increased, whereas the pore size decreased. The surface Fe concentration was increased in spite of the Fe aggregation inside the carbon matrix. The catalytic activity enhancement was achieved due to the increase in the specific surface area and the surface Fe concentration, but was lowered due to the decrease in the pore size, which was disadvantageous for the penetration of the electrolyte and the mass transfer.

  6. O processo narrativo nas manifestações do fenômeno depressivo

    Modesto Leite Rolim Neto

    2005-01-01

    Full Text Available El objetivo de este trabajo es evaluar la importancia del proceso narrativo en la descripción de los significados involucrados en el fenómeno depresivo. La población investigada se constituyo de 324 pacientes que buscaron los servicios clínicos y psicológicos en el Centro de Salud Alves Ferreira en la ciudad de Aparecida en el Hospital Municipal de Santa Cruz, localizado en el interior de Paraíba, teniendo como motivo de consulta sufrimiento y/o dolor psíquico. De los 324 fue compuesta una muestra de 159 pacientes, con adolescentes y adultos de ambos sexos. Para la recolección de datos fue utilizada una entrevista narrativa. El análisis de esta entrevista siguió un procedimiento delineado por Shutz. Las narrativas proporcionan una oportunidad importante de rever los conceptos, discutir historias de vida y escuchar posicionamientos en los recuentos episódicos de la depresión. Las narrativas se constituyen en un factor determinante para considerar a través de la palabra los conflictos inherentes.

  7. El fenómeno del Greenwashing y su impacto sobre los consumidores

    Moritz Hallama

    2011-07-01

    Full Text Available Hoy en día y mediante una publicidad sofisticada, las empresas tratan de proyectar una imagen respetuosa con el medio ambiente en la percepción de los consumidores. Esta imagen no refleja necesariamente la realidad. Se habla de “Greenwashing” cuando una empresa utiliza la ampliación selectiva de información medioambiental positiva con la finalidad de causar una imagen distorsionada donde los aspectos positivos predominan mas del debido. Este artículo pretende de abordar este fenómeno y avaluar su existencia, importancia y el efecto causado sobre los consumidores mediante el diseño de una metodología piloto para la investigación, aplicando ésta a una muestra de estudiantes. Los resultados indican que la imagen transmitida por la publicidad de cinco grandes empresas seleccionadas contrasta con ejemplos de mala gestión y que esta manipulación influye en la percepción que tiene la muestra encuestada. Los estudiantes de Ciencias Ambientales encuestados presentan ser ligeramente más resistentes contra el Greenwashing debido a su formación, pero también incorporan mayoritariamente el discurso oficial procedente de las relaciones públicas empresariales.

  8. Modeling thermodynamics of Fe-N phases; characterisation of e-Fe2N1-z

    Pekelharing, M.I.; Böttger, A.; Somers, Marcel A.J.; Steenvoorden, M.P.; van der Kraan, A.M.; Mittemeijer, E.J.

    (z=0) and configuration B for Fe2N2/3 (z=1/3). So far, only configuration B was identified unambiguously by diffraction techniques [1,3]. In the present work homogeneous -nitride powders prepared at 723 K, having nitrogen contents ranging from 26.1 at. % N (z=0.29) to 31.1 at.% N (z=0.10), were......In order to arrive at modeling the thermodynamics of Fe-N phases, including long-range (LRO) and short-range ordering (SRO) of the N atoms, it is important to understand the role of N interstitially dissolved in an Fe-host lattice. The crystal structure of -Fe2N1-z consists of an h.c.p. iron...... sublattice and a hexagonal nitrogen sublattice formed by octahedral interstices of the Fe sublattice [1]. Two ground-state structures have been proposed for the ordered arrangement of the N atoms on their own sublattice [1], which were shown to be thermodynamically favourable [2]: configuration A for Fe2N1...

  9. Fenólicos totais e atividade antioxidante do extrato aquoso de broto de feijão-mungo (Vigna radiata L. Total phenolics and antioxidant activity of the aqueous extract of mung bean sprout (Vigna radiata L.

    Vera Lúcia Arroxelas Galvão de Lima

    2004-03-01

    Full Text Available OBJETIVO: Considerando a importância dos compostos fenólicos em alimentos e que o broto de feijão-mungo vem sendo incluído na culinária brasileira, este estudo teve como objetivo quantificar o teor de fenólicos totais deste vegetal e avaliar a ação antioxidante do seu extrato aquoso. MÉTODOS: Os compostos fenólicos foram extraídos por quatro sistemas de solventes e dois métodos de extração, os quais foram diferenciados no tempo (2 e 1h e número de extrações (2 e 3 extrações. Os fenólicos totais dos extratos foram quantificados por método espectrofotométrico. RESULTADOS: Os extratos obtidos com água à temperatura ambiente (28ºC, nos dois métodos de extração, foram os que apresentaram maior quantidade de fenólicos totais, sem contudo apresentar diferença significativa entre eles. O método II, que consistiu de três extrações em 1h, pode ser considerado o melhor por ter utilizado menor tempo de extração. O extrato aquoso em sistema modelo b-caroteno/ácido linoléico exibiu ação antioxidante (48,07% de inibição da oxidação, entretanto foi inferior ao padrão BHT. CONCLUSÃO: O broto de feijão-mungo possui considerável quantidade de fenólicos totais, compostos responsáveis por sua ação antioxidante, cujo consumo pode proporcionar efeitos benéficos à saúde.OBJECTIVE: Considering the importance of phenolic compounds in foods and the increasing consumption of mung bean sprouts in Brazil, this study had the objective of quantifying the total phenolic content in this vegetable and to assess the antioxidant activity of its aqueous extract. METHODS: The phenolic compounds were extracted by four solvent systems and two extraction methods, which were different in time (2 and 1h and in number of extractions (2 and 3 extractions. The total phenolic content of the extracts were quantified by the spectrophotometric method. RESULTS: The extracts obtained with water at room temperature (28ºC in both extraction

  10. Aplicações de novas metodologias analíticas no estudo de compostos fenólicos em matrizes alimentares

    Sequeiros, Rute Carina Pereira

    2009-01-01

    O crescente interesse no estudo dos compostos fenólicos, particularmente os ácidos fenólicos, deve-se às propriedades antioxidantes que evidenciam, acreditando-se que possam desempenhar um importante papel na prevenção de doenças cardiovasculares e do cancro. Neste sentido, é de todo o interesse o desenvolvimento de métodos analíticos capazes de determinar e quantificar os compostos fenólicos numa vasta gama de alimentos. O presente trabalho consistiu no desenvolvimento, optimização, validaçã...

  11. Cambios en contenido de compuestos fenólicos y color de extractos de Jamaica (Hibiscus sabdariffa) sometidos a calentamiento con energía de microondas

    Hid Cadena, Rebeca; Bautista Ortín, Ana Belén; Ortega Regules, Ana E.; Welti Chanes, Jorge S.; Lozada Ramírez, J. Daniel; Anaya de Parrodi, Cecilia

    2010-01-01

    En este trabajo se realizó la extracción acuosa de compuestos fenólicos, principalmente antocianinas, provenientes de cálices de jamaica (Hibiscus sabdariffa). El extracto fue calentado por microondas a diferentes temperaturas (30, 40, 50, 60, 70 y 80°C) durante 20 min, tomando una alícuota cada 5 min. En el extracto con y sin calentamiento se determinó el contenido de compuestos fenólicos y los parámetros colorimétricos. Para el contenido de compuestos fenólicos totales se observaron pérdida...

  12. Extracción de compuestos fenólicos de la uva al vino. Papel de los enzimas de maceración

    Romero Cascales, María Inmaculada

    2008-01-01

    La extracción de los compuestos fenólicos, responsables de ciertas características de color de los vinos, va a depender entre otros, de la degradación de la pared celular, por lo que el uso de enzimas pectolíticos podría ser una técnica adecuada para obtener vinos con mayor carga polifenólica. Los resultados mostraron que la extracción de los compuestos fenólicos durante la maceración es incompleta. Además, estudiando la extractabilidad de los compuestos fenólicos en diferentes variedade...

  13. Análisis del downsizing (reducción de plantilla como fenómeno psicosocial

    CRISTÓBAL JIMÉNEZ JIMÉNEZ

    2005-01-01

    Full Text Available En este trabajo se analiza el downsizing como fenómeno recurrente y de gran actualidad en el mundo de los negocios y de las organizaciones, delimitando su concepto, señalando su incidencia y destacando sus principales características. Después de enmarcar el downsizing en el ámbito específico del Estrés Laboral, se argumenta la importancia y conveniencia de considerarlo, de pleno derecho, como fenómeno psico-socio-laboral, señalando algunas implicaciones de interés para el ámbito de los Recursos Humanos en el marco de la Prevención de Riesgos Laborales.

  14. Biodegradación de compuestos fenólicos del alpechín con Aspergillus terreus

    García Paeja, María P.

    1992-04-01

    Full Text Available Olive mill wastewater degradation by Aspergillus terreus and under aerobic conditions at 28°C, was measured by the parameter of phenol content. We have explored the effect of different concentrations of olive mill wastewater upon the activity of Aspergillus terreus. Through HPLC, 10 phenol compounds (90% of the total phenolic content of the olive mill wastewater were identified.Se estudia la degradación de alpechines con Aspergillus terreus en condiciones de aerobiosis y temperatura de 28°C, utilizando como parámetro el contenido fenólico. Se analiza el efecto de la concentración de alpechín con Aspergillus terreus utilizando el mismo parámetro. Se han identificado por cromatografía líquida de alta eficacia (CLAE 10 compuestos fenólicos que suponen el 90% del total del alpechín.

  15. El fenómeno de la migración en aves: una mirada desde la Orinoquia

    Ocampo-Peñuela, Natalia

    2010-01-01

    La migración es un fenómeno que ha llamado la atención de investigadores a lo largo del mundo y de la historia de la ciencia. Este proceso biológico ha sido bien estudiado en aves, sin embargo, en Colombia y, especialmente en la región de la Orinoquia, aún queda mucho por conocer sobre estas viajeras. Este artículo presenta el fenómeno de la migración Neotropical en aves; primero se evidencia una recopilación de bibliografía sobre la migración en aves y algunos de sus aspectos más...

  16. Revealing Rembrandt

    Andrew J Parker

    2014-04-01

    Full Text Available The power and significance of artwork in shaping human cognition is self-evident. The starting point for our empirical investigations is the view that the task of neuroscience is to integrate itself with other forms of knowledge, rather than to seek to supplant them. In our recent work, we examined a particular aspect of the appreciation of artwork using present-day functional magnetic resonance imaging (fMRI. Our results emphasised the continuity between viewing artwork and other human cognitive activities. We also showed that appreciation of a particular aspect of artwork, namely authenticity, depends upon the co-ordinated activity between the brain regions involved in multiple decision making and those responsible for processing visual information. The findings about brain function probably have no specific consequences for understanding how people respond to the art of Rembrandt in comparison with their response to other artworks. However, the use of images of Rembrandt’s portraits, his most intimate and personal works, clearly had a significant impact upon our viewers, even though they have been spatially confined to the interior of an MRI scanner at the time of viewing. Neuroscientific studies of humans viewing artwork have the capacity to reveal the diversity of human cognitive responses that may be induced by external advice or context as people view artwork in a variety of frameworks and settings.

  17. O fenômeno recrutamento e seleção de enfermeiros em hospitais: um enfoque fenomenológico The phenomenon of recruitment and selecting nurses in the hospital: a phenomenon approach

    Heloisa Helena Ciqueto Peres

    1997-04-01

    Full Text Available Este estudo teve como objetivo, desvelar o processo de recrutamento e seleção de enfermeiros a partir da experiência dos sujeitos que vi venciam essa prática. Para tanto buscou-se como trajetória metodológica a fenomenologia, na modal idade do fenômeno situado no referencial de Joel . Martins. Assim, o estudo foi realizado a partir do discurso de oito enfermeiros que experienciam o fenômeno. A análise dos depoimentos contemplou os momentos de descrição, redução e compreensão fenomenológicas, até o desvelamento da essencialidade do fenômeno investigado. Da análise fenomenológica dos discursos foi possível resgatar aspectos que representam a compreensão geral do processo de recrutamento e seleção de enfermeiros. Dessa forma, a essencialidade do fenômeno desvelado caracterizou-se pelas relações Homem, Organizações e Sociedade, relações essas de interdependência permeadas por múltiplos determinantes transituacionais. Nessa perspectiva, novos horizontes abriram-se no que tange o pensar recrutamento e seleção em enfermagem.This study had the purpose of showing the recruitment and selective process of nurses from their own experiences going through this process. The phenomenology was used as the methodological course, the phenomenon was based on the references by Joel Martins. The study was done from the speeches of eight nurses who went through the recruitment and selective process. The analysis of the speeches followed the moments of the phenomenological description, reduction and understanding until revealing the essence of the recruitment and selective process of nurses. From the phenomenological analysis of the speeches it was possible to get the aspects that represent the general understanding of the recruitment and selective process of nurses. In this way, the essence of the phenomenon was characterized by the relation among the man, the Company and the society, these relations were influenced by several

  18. The hydrological and geochemical isolation of a freshwater bog within a saline fen in north-eastern Alberta

    S.J. Scarlett; J.S. Price

    2013-01-01

    In the oil sands development region near Fort McMurray, Alberta, wetlands cover ~62 % of the landscape, and ~95 % of these wetlands are peatlands. A saline fen was studied as a reference site for peatland reclamation. Despite highly saline conditions, a freshwater bog was observed in the path of local saline groundwater flow. The purpose of this study was to identify the hydrological controls that have allowed the development and persistence of a bog in this setting. The presence of bog veget...

  19. CRN-1, a Caenorhabditis elegans FEN-1 homologue, cooperates with CPS-6/EndoG to promote apoptotic DNA degradation

    Parrish, Jay Z.; Yang, Chonglin; Shen, Binghui; Xue, Ding

    2003-01-01

    Oligonucleosomal fragmentation of chromosomes in dying cells is a hallmark of apoptosis. Little is known about how it is executed or what cellular components are involved. We show that crn-1, a Caenorhabditis elegans homologue of human flap endonuclease-1 (FEN-1) that is normally involved in DNA replication and repair, is also important for apoptosis. Reduction of crn-1 activity by RNA interference resulted in cell death phenotypes similar to those displayed by a mutant lacking the mitochondr...

  20. Uso de compuestos fenólicos para el tratamiento de patologías causadas por Helicobacter pylori

    Carrascosa, Alfonso V.; Martínez-Rodríguez, Adolfo J.; López-Brea, Manuel; Alarcón, Teresa; Rodrigo, Sandra

    2010-01-01

    La presente invención se refiere a una serie de compuestos fenólicos que pueden ser extraídos de la uva o del vino y que poseen capacidad bacericida contra Helicobacter pylori, por lo que dichos compuestos son útiles para la fabricación de un medicamento para el tratamiento y/o prevención de patologías causadas por esta bacteria o como aditivos en alimentos funcionales o productos alimentarios.

  1. Uso de compuestos fenólicos para el tratamiento de patologías causadas por helicobacter pylori

    Carrascosa, Alfonso V.; Martínez-Rodríguez, Adolfo J.; López-Brea, Manuel; Alarcón, Teresa; Rodrigo, Sandra

    2010-01-01

    [ES] La presente invención se refiere a una serie de compuestos fenólicos que pueden ser extraídos de la uva o del vino y que poseen capacidad bactericida contra Helicobacter pylori, por lo que dichos compuestos son útiles para la fabricación de un medicamento para el tratamiento y/o prevención de patologías causadas por esta bacteria o como aditivos en alimentos funcionales o productos alimentarios.

  2. A cryptic targeting signal creates a mitochondrial FEN1 isoform with tailed R-Loop binding properties.

    Lawrence Kazak

    Full Text Available A growing number of DNA transacting proteins is found in the nucleus and in mitochondria, including the DNA repair and replication protein Flap endonuclease 1, FEN1. Here we show a truncated FEN1 isoform is generated by alternative translation initiation, exposing a mitochondrial targeting signal. The shortened form of FEN1, which we term FENMIT, localizes to mitochondria, based on import into isolated organelles, immunocytochemistry and subcellular fractionation. In vitro FENMIT binds to flap structures containing a 5' RNA flap, and prefers such substrates to single-stranded RNA. FENMIT can also bind to R-loops, and to a lesser extent to D-loops. Exposing human cells to ethidium bromide results in the generation of RNA/DNA hybrids near the origin of mitochondrial DNA replication. FENMIT is recruited to the DNA under these conditions, and is released by RNase treatment. Moreover, high levels of recombinant FENMIT expression inhibit mtDNA replication, following ethidium bromide treatment. These findings suggest FENMIT interacts with RNA/DNA hybrids in mitochondrial DNA, such as those found at the origin of replication.

  3. In vitro anti-coxsackievirus B3 effect of ethyl acetate extract of Tian-hua-fen

    Zhen-Hong Li; Bao-Ming Nie; Hong Chen; Shu-Yun Chen; Ping He; Yang Lu; Xiao-Kui Guo; Jing-Xing Liu

    2004-01-01

    AIM: To investigation the anti-coxsackievirus B3 (CVB3m)effect of the ethyl acetate extract of Tian-hua-fen on HeLa cells infected with CVB3m.METHODS: HeLa cells were infected with CVB3m and the cytopathic effects (CPE) were observed through light microscope and crystal violet staining on 96-well plate and A600 was detected using spectrophotometer. The protective effect of the extract to HeLa cells and the mechanism of the effect were also evaluated through the change of CPE and value of A600.RESULTS: The extract had some toxicity to HeLa cells at a higher concentration while had a marked inhibitory effect on cell pathological changes at a lower concentration.Consistent results were got through these two methods.We also investigated the mechanism of its anti-CVB3m effect and the results indicated that the extract represented an inhibitory effect through all the processes of CVB3m attachment, entry, biosynthesis and assemble in cells.CONCLUSION: The results demonstrate that the ethyl acetate extract of Tian-hua-fen has a significant protective effect on HeLa cells infected with CVB3m in a dose-dependent manner and this effect exists through the process of CVB3m attachment, entry, biosynthesis and assemble in cells,suggesting that the ethyl acetate extract of Tian-hua-fen can be developed as an anti-virus agent.

  4. The Overexpression of FEN1 and RAD54B May Act as Independent Prognostic Factors of Lung Adenocarcinoma

    Hwang, Jau-Chung; Sung, Wen-Wei; Tu, Hung-Pin; Hsieh, Kun-Chou; Yeh, Chung-Min; Chen, Chih-Jung; Tai, Hui-Chun; Hsu, Chao-Tien; Shieh, Grace S.; Chang, Jan-Gowth; Yeh, Kun-Tu; Liu, Ta-Chih

    2015-01-01

    Synthetic lethality arises when a combination of mutations in two or more genes leads to cell death. However, the prognostic role of concordant overexpression of synthetic lethality genes in protein level rather than a combination of mutations is not clear. In this study, we explore the prognostic role of combined overexpression of paired genes in lung adenocarcinoma. We used immunohistochemical staining to investigate 24 paired genes in 93 lung adenocarcinoma patients and Kaplan-Meier analysis and Cox proportional hazards models to evaluate their prognostic roles. Among 24 paired genes, only FEN1 (Flap endonuclease 1) and RAD54B (RAD54 homolog B) were overexpressed in lung adenocarcinoma patients with poor prognosis. Patients with expression of both FEN1 and RAD54B were prone to have advanced nodal involvement and significantly poor prognosis (HR = 2.35, P = 0.0230). These results suggest that intensive follow up and targeted therapy might improve clinical outcome for patients who show expression of both FEN1 and RAD54B. PMID:26431531

  5. Seasonal variation in the phenol content of Eugenia uniflora L. leaves Variação sazonal nos teores de fenóis de folhas de Eugenia uniflora L

    R.M Santos

    2011-01-01

    Full Text Available Hydrolysable tannins, total phenols and flavonoids in Eugenia uniflora leaves were monthly analysed for one year. The results were correlated with climate conditions (rainfall, humidity, cloudiness and mean temperature through chemometric methods. Principal component analysis revealed high levels of hydrolysable tannins in the rainy season, whereas flavonoids were mainly produced in the dry season. These facts suggest that climatic changes may be one of the factors affecting phenol levels in Eugenia uniflora.Taninos hidrolisáveis, fenóis totais e flavonóides presentes em folhas de Eugenia uniflora foram quantificados mensalmente durante um ano. Os resultados foram correlacionados com as condições climáticas (pluviosidade, umidade, nebulosidade e temperatura média através de métodos quimiométricos. Análise de componentes principais revelou a ocorrência de altos teores de taninos hidrolisáveis durante a estação de chuvas, enquanto os flavonóides foram produzidos principalmente na estação seca. Estes fatos sugerem que mudanças climáticas podem ser um dos fatores que afetam os níveis de fenóis em Eugenia uniflora.

  6. Using multi-proxy palaeoecology to test a relict status of refugial populations of calcareous-fen species in the Western Carpathians

    Hájková, Petra; Horsák, M.; Hájek, Michal; Jankovská, Vlasta; Jamrichová, Eva; Moutelíková, J.

    2015-01-01

    Roč. 25, č. 4 (2015), s. 702-715. ISSN 0959-6836 Institutional support: RVO:67985939 Keywords : biodiversity * calcareous fen * fossil record * Holocene extinction * Western Carpathians Subject RIV: EF - Botanics Impact factor: 2.283, year: 2014

  7. Methanotrophic and Methanogenic Communities in Swiss Alpine Fens Dominated by Carex rostrata and Eriophorum angustifolium.

    Cheema, Simrita; Zeyer, Josef; Henneberger, Ruth

    2015-09-01

    Vascular plants play a key role in controlling CH4 emissions from natural wetlands, because they influence CH4 production, oxidation, and transport to the atmosphere. Here we investigated differences in the abundance and composition of methanotrophic and methanogenic communities in three Swiss alpine fens dominated by different vascular plant species under natural conditions. The sampling locations either were situated at geographically distinct sites with different physicochemical properties but the same dominant plant species (Carex rostrata) or were located within the same site, showing comparable physicochemical pore water properties, but had different plant species (C. rostrata or Eriophorum angustifolium). All three locations were permanently submerged and showed high levels of CH4 emissions (80.3 to 184.4 mg CH4 m(-2) day(-1)). Soil samples were collected from three different depths with different pore water CH4 and O2 concentrations and were analyzed for pmoA and mcrA gene and transcript abundance and community composition, as well as soil structure. The dominant plant species appeared to have a significant influence on the composition of the active methanotrophic communities (transcript level), while the methanogenic communities differed significantly only at the gene level. Yet no plant species-specific microbial taxa were discerned. Moreover, for all communities, differences in composition were more pronounced with the site (i.e., with different physicochemical properties) than with the plant species. Moreover, depth significantly influenced the composition of the active methanotrophic communities. Differences in abundance were generally low, and active methanotrophs and methanogens coexisted at all three locations and depths independently of CH4 and O2 concentrations or plant species. PMID:26092454

  8. Temporal variability of CO2 and CH4 fluxes of a rewetted fen in NE Germany

    Franz, Daniela; Larmanou, Eric; Koebsch, Franziska; Augustin, Jürgen; Sachs, Torsten

    2015-04-01

    During the last 20 years, restoring degraded peatlands became common practice in the context of climate protection, as it is expected to reduce their greenhouse gas (GHG) contribution to the atmosphere in the long term. However, suboptimal management decisions can even impair the GHG budget beyond the "restoration effect" during the first years of the rewetting. To improve future restoration management, the GHG dynamics following rewetting have to be quantified and understood. Apart from this, knowledge on the variability of the gas exchange and the respective drivers over different time scales is still lacking, though especially important for process understanding and advancement of estimations. Using the eddy covariance (EC) technique we investigate CH4 and CO2 flux dynamics between the atmosphere and a highly degraded minerotrophic fen grassland flooded in 2004/2005. The study site is located in the Peene River valley (53°52'N, 12°52'E), NE Germany. It is part of the Terrestrial Environmental Observatories Network (TERENO) spanning across Germany. In the course of flooding, a shallow lake (30-80 cm depth) developed in the centre of the rewetted area and persisted until now. The footprint of the EC measurements covers both the shallow lake and non-permanently inundated parts surrounding the lake. We will present CO2 and CH4 flux data covering one year since the system was newly established. We applied wavelet analysis and wavelet coherence to detect the multi-scale temporal variability of ecosystem gas exchange and the respective drivers by splitting time series into spectral and temporal components. Thus, transitions of ecosystem processes during the observation period are considered. Both methods are performed on continuous EC data over one year in case of CO2 and shorter measurement periods in the course of the growing season for CH4, due to data gaps. The addressed scales of temporal variation range from hour to week and season for CH4 and CO2, respectively.

  9. Carbon dioxide fluxes at an intensively cultivated temperate lowland peatland in the East Anglian Fens, UK

    R. Morrison

    2013-03-01

    Full Text Available This study reports the first recorded CO2 flux measurements of a drained and intensively cultivated lowland peatland in the East Anglian Fens (UK using the eddy covariance technique. Measurements were made over a complete lettuce crop rotation and a subsequent fallow period. Maximum average daytime CO2 uptake and nocturnal loss rates were −10.39 and 7.63 μmol CO2 m−2 s−1, respectively. Daily CO2 budgets ranged from a net loss of 4.7 to a small net uptake of −1.23 g CO2-C m−2 d−1. Total vertical land/atmosphere CO2 losses were estimated at 227.11 ± 46.5 g CO2-C m−2 for a~120 day measurement period. Losses over a sixty day interval between field preparation and disking of the field at the end of the crop cycle were 74.22 ± 18.8 g CO2-C m−2. The site lost 152.89 ± 30.6 g CO2-C m−2 d−1 during a sixty day fallow period. Net ecosystem production was estimated at 117.72 ± 18.8 g CO2-C m−2 during the crop cycle and 270.61 ± 46.49 g CO2-C m−2 for the entire measurement period when harvested crop exports were accounted for. These results represent the first micrometeorological measurements obtained over degraded lowland peatland in Britain, and illustrate the scale of CO2 losses associated with agricultural production on temperate organic soils.

  10. Rich fen development in SE Poland and its response to climate changes and human impacts in the late Holocene

    Gałka, Mariusz; Apolinarska, Karina; Aunina, Liene; Feurdean, Angelica; Hutchinson, Simon; Kołaczek, Piotr

    2016-04-01

    Rich fens are one of the most important wetland ecosystems due to their high species-richness and unique species composition. They are occupied by endangered, vulnerable and protected plants, such as Cladium mariscus and Schoenus ferrugineus. For this reason knowledge of the history of rich fens is important for the development of effective management strategies to protect or restore these widely threatened habitats. Our palaeoecological study reconstructs the development of Bagno Serebryskie rich fen (ca. 376 ha), a site with the largest population of Cladium mariscus in CE Europe, and its response to climate changes and human impacts during the last 3500 years. For this we analyse two peat profiles at this site, at a high resolution (1 and 2 cm) using multi-aspect palaeoecological analyses (plant macrofossils, pollen, molluscs, geochemistry, charcoal and AMS 14C radiocarbon) to assess the impact of climate changes, human activity, and fires on local vegetation. Local plant succession in our two coring points followed parallel trajectories; after a lake stage, ca. 1800 cal yr BP (core I) and 3300 cal yr BP (core II), fen species e.g. Menyanthes trifoliata, Mentha aquatic, Carex lasiocarpa appeared, followed at ca. 500 cal. yr BP by Cladium mariscus, which is currently the dominant plant species in the Bagno Serebryskie peatland. In one peat profile (core II) we found abundant macrocharcoal particles at 1050, 700, 400 cal yr BP and the present, but fires had no significant impact on the development of the mire. In the other peat profile (core I) we noted four stages (at 2300, 1350, 400, 100 cal yr BP) with an increasing diversity of mollusc species typical of overgrown, but permanent water bodies. Their increased abundance and diversity can be linked to a rise in mire water table at these times. Our studies indicate that rich fens can provide reliable sites for palaeoecological reconstruction of the late Holocene providing valuable information that can be applied

  11. Filtering fens: mechanisms explaining phosphorus-limited hotspots of biodiversity in wetlands adjacent to heavily fertilized areas.

    Cusell, Casper; Kooijman, Annemieke; Fernandez, Filippo; van Wirdum, Geert; Geurts, Jeroen J M; van Loon, E Emiel; Kalbitz, Karsten; Lamers, Leon P M

    2014-05-15

    The conservation of biodiverse wetland vegetation, including that of rich fens, has a high priority at a global scale. Although P-eutrophication may strongly decrease biodiversity in rich fens, some well-developed habitats do still survive in highly fertilized regions due to nutrient filtering services of large wetlands. The occurrence of such nutrient gradients is well-known, but the biogeochemical mechanisms that determine these patterns are often unclear. We therefore analyzed chemical speciation and binding of relevant nutrients and minerals in surface waters, soils and plants along such gradients in the large Ramsar nature reserve Weerribben-Wieden in the Netherlands. P-availability was lowest in relatively isolated floating rich fens, where plant N:P ratios indicated P-limitation. P-limitation can persist here despite high P-concentrations in surface waters near the peripheral entry locations, because only a small part of the P-input reaches the more isolated waters and fens. This pattern in P-availability appears to be primarily due to precipitation of Fe-phosphates, which mainly occurs close to entry locations as indicated by decreasing concentrations of Fe- and Al-bound P in the sub-aquatic sediments along this gradient. A further decrease of P-availability is caused by biological sequestration, which occurs throughout the wetland as indicated by equal concentrations of organic P in all sub-aquatic sediments. Our results clearly show that the periphery of large wetlands does indeed act as an efficient P-filter, sustaining the necessary P-limitation in more isolated parts. However, this filtering function does harm the ecological quality of the peripheral parts of the reserve. The filtering mechanisms, such as precipitation of Fe-phosphates and biological uptake of P, are crucial for the conservation and restoration of biodiverse rich fens in wetlands that receive eutrophic water from their surroundings. This seems to implicate that biodiverse wetland

  12. How a regional aquifer, a local aquifer and an oxbow lake impact on hydrological and biogeochemical processes in ariparian fen-meadow ecosystem

    Hoffmann, Carl Christian; Pedersen, Morten Lauge; Rasmussen, K R

    2009-01-01

    The groundwater flow pattern through a riparian fen-meadow was investigated by use of piezometer transects, soil survey, measurements of piezometric heads and measurements of hydraulic conductivity. Groundwater was sampled from piezometers and analysed for nitrate-N. Water balances and nitrate-N mass balances were calculated. The groundwater flow pattern through a riparian fen-meadow was investigated by use of piezometer transects, soil survey, measurements of piezometric heads and measure...

  13. Análisis comparativo de compuestos fenólicos totales y actividad antioxidante de cuatro marcas de tisanas de Hibiscus sabdariffa (Malvaceae) comercializadas en Costa Rica

    Melissa Agüero; Cindy Segura; Jonathan Parra

    2014-01-01

    Las tisanas de rosa de Jamaica (Hibiscus sabdariffa) son consumidas en Costa Rica por su conocido efecto cardioprotector asociado a la presencia de compuestos fenólicos, principalmente antocianinas. Este trabajo estableció diferencias en el perfil de compuestos fenólicos y su actividad anti-radical entre diferentes comercializadores de tisanas de Hibiscus sabdariffa en Costa Rica. Se identificaron cualitativamente taninos, flavonoides y antocianinas. Se cuantificó la cantidad total de compues...

  14. Análisis comparativo de compuestos fenólicos totales y actividad antioxidante de cuatro marcas de tisanas de Hibiscus sabdariffa (Malvaceae comercializadas en Costa Rica

    Melissa Agüero

    2014-01-01

    Full Text Available Las tisanas de rosa de Jamaica (Hibiscus sabdariffa son consumidas en Costa Rica por su conocido efecto cardioprotector asociado a la presencia de compuestos fenólicos, principalmente antocianinas. Este trabajo estableció diferencias en el perfil de compuestos fenólicos y su actividad anti-radical entre diferentes comercializadores de tisanas de Hibiscus sabdariffa en Costa Rica. Se identificaron cualitativamente taninos, flavonoides y antocianinas. Se cuantificó la cantidad total de compuestos fenólicos por el método de  Folin-Ciocalteu y se cuantificó la actividad antioxidante con el método de DPPH. Todas las marcas comerciales demostraron presencia de compuestos fenólicos, incluyendo antocianinas; sin embargo, se encontraron diferencias significativas en el contenido de compuestos fenólicos y actividad anti-radical, entre los diferentes productores de tisanas. Por ello, se concluye que en el mercado costarricense, el perfil en compuestos fenólicos de las tisanas en estudio varía de acuerdo con el productor.

  15. Análisis comparativo de compuestos fenólicos totales y actividad antioxidante de cuatro marcas de tisanas de Hibiscus sabdariffa (Malvaceae comercializadas en Costa Rica

    Melissa Agüero

    2014-01-01

    Full Text Available Las tisanas de rosa de Jamaica (Hibiscus sabdariffa son consumidas en Costa Rica por su conocido efecto cardioprotector asociado a la presencia de compuestos fenólicos, principalmente antocianinas. Este trabajo estableció diferencias en el perfil de compuestos fenólicos y su actividad anti-radical entre diferentes comercializadores de tisanas de Hibiscus sabdariffa en Costa Rica. Se identificaron cualitativamente taninos, flavonoides y antocianinas. Se cuantificó la cantidad total de compuestos fenólicos por el método de Folin-Ciocalteu y se cuantificó la actividad antioxidante con el método de DPPH. Todas las marcas comerciales demostraron presencia de compuestos fenólicos, incluyendo antocianinas; sin embargo, se encontraron diferencias significativas en el contenido de compuestos fenólicos y actividad anti-radical, entre los diferentes productores de tisanas. Por ello, se concluye que en el mercado costarricense, el perfil en compuestos fenólicos de las tisanas en estudio varía de acuerdo con el productor.

  16. Microbiota dynamics related to environmental conditions during the fermentative production of Fen-Daqu, a Chinese industrial fermentation starter.

    Zheng, Xiao-Wei; Yan, Zheng; Nout, M J Robert; Smid, Eddy J; Zwietering, Marcel H; Boekhout, Teun; Han, Jian-Shu; Han, Bei-Zhong

    2014-07-16

    Chinese Daqu is used as a starter for liquor and vinegar fermentations. It is produced by solid state fermentation of cereal-pulse mixtures. A succession of fungi, lactic acid bacteria and Bacillus spp. was observed during the production of Daqu. Mesophilic bacteria followed by fungi, dominated the first phase of fermentation. Next, lactic acid bacteria increased in relative abundance, resulting in an increase of the acidity of Daqu. At the final stages of fermentation, Bacillus spp. and thermophilic fungi became the dominant groups, possibly due to their tolerance to low water activity and high temperature. Both culture-dependent and culture-independent analyses confirmed that Bacillus spp. were ubiquitous throughout the process. Yeast species such as Wickerhamomyces anomalus, Saccharomycopsis fibuligera and Pichia kudriavzevii were present throughout almost the entire fermentation process, but the zygomycetous fungus Lichtheimia corymbifera proliferated only during the final stages of fermentation. Canonical correspondence analysis (CCA) revealed the significance of acidity, moisture content and temperature in correlation with the composition of the microbial communities at different stages. PMID:24863368

  17. Component analysis and quantitative structure-retention relationship study of aroma compounds in fen liquor%汾酒香味成分分析及定量结构-色谱保留相关研究

    乔华; 李美萍; 马艳红; 费珊珊; 张生万

    2012-01-01

    以清香型汾酒为研究对象,采用气相色谱/质谱联用方法,分析了汾酒中的主要香味成分,利用btericandE1。ctronicDescriptors(SEDs)建立了预测香味成分的定量结构一色谱保留相关模型,发现汾酒中主要香味成分酯、醇、酸、醚、烃、醛、酮的保留时间分别与不同的SEDs参数有良好的相关性,建模相关系数分别为酯R=0.991、醇R=O.995、酸R=0.995、醚和烃R=0.995、醛酮R=0.969,留-法交互检验(Leave-one-out,Loo)相关系数分别为酯RLoo=0.986、醇R。=0.986、酸RLoo=0.991、醚和烃RLoo=0.944、醛酮RLoo=0.932。结果表明,所建模型具有良好的稳定性和预测能力.为白酒中香味成分的分离检测提供了有效的理论依据。%Fen liquor was selected as the objective and its aroma components were studied by gas chromatography/mass spectrometry. To predict the retention times of aroma components in Fen liquor, the quantitative structure-retention relationship models were generated by using Steric and Electronic Descriptors (SEDs).It was found that retention times of the aroma components in Fen liquor had good relationships with different selected SEDs parameters.The correlation coefficients(R)for the built models were. esters R = 0.991, alcohols R =0.995,acids R = 0.995, ethers and hydrocarbons R = 0.995, aldehydes and ketones R = 0.969, and the leave- one- out ( LOO ) cross- validation coefficients ( RLoo ) were: esters RLoo = 0.986, alcohols RLoo = 0.986, acids RLoo =0.991,ethers and hydrocarbons RLoo = 0.944, aldehydes and ketones RLoo = 0.932.Results showed that the models were of good stability and predictability, and they were useful to develop methods for identifying and separating aroma components in Chinese liquor.

  18. Boko Haram: análisis del fenómeno terrorista en Nigeria

    Francisco Javier Torregrosa López

    2016-04-01

    Full Text Available El terrorismo sufre cambios en la actualidad y evoluciona a la par que el resto del mundo. Boko Haram supone el ejemplo perfecto de un nuevo terrorismo emergente, alimentado por la globalización y la economía, pero fundamentado a su vez en pilares tan antiguos como el fanatismo religioso y los conflictos interculturales. En este artículo se trata de revisar las claves del nacimiento y desarrollo de este grupo terrorista: las características de su país de origen, los elementos que llevaron al surgimiento de este grupo terrorista, qué estrategias de asalto y financiación utiliza en la actualidad y cómo lleva a cabo Boko Haram: análisis del fenómeno terrorista en Nigeria Rafael López Pérez Doctor en Psicología. Presidente de la Fundación Universitaria Behavior & Law, Madrid, España. rlopez@behaviorandlaw.com Nahikari Sánchez Herrero Magíster en Seguridad. Especialidad en perfiles terroristas. Profesora de Crímina, Centro para el estudio y prevención de la delincuencia, Pamplona, España. nahikari.sanchez@crimina.es Ángel García Collantes Doctor en Derecho. Director de la Cátedra de Análisis de Conducta UDIMA - Fundación Universitaria Behavior & Law, Madrid, España. angel.garcia.c@udima.es Francisco Javier Torregrosa López Magíster en Criminología y Ciencias Forenses. Investigador en la Fundación Universitaria Behavior & Law, Alicante, España. javiertorregrosalopez@behaviorandlaw.com David Garriga Guitart Magíster en Mundo Árabe e Islámico. Analista de Terrorismo Yihadista, Fundación Universitaria Behavior & Law, Barcelona, España. dgarriga@behaviorandlaw.com su reclutamiento, así como su relación con otros grupos terroristas. Por último, con base en la teoría analizada, se realizará un análisis prospectivo sobre qué dirección es más probable que sigan sus acciones durante un futuro inmediato y a largo plazo. Las conclusiones alcanzadas por los autores indican que Boko Haram con probabilidad continuar

  19. Modeling ecohydrological controls on net CO2 exchange of a boreal fen

    Grant, R.; Mezbahuddin, S.; Flanagan, L.

    2012-04-01

    Hydrology is one of the key controls governing peatland carbon balance under current and future climatic conditions. Seasonal variations in soil water content and water table depths can alter the balance between peatland primary production and respiration and so cause a peatland to change between a sink and a source of carbon. Seasonal and interannual variation in peat hydrology can affect primary production and respiration through its influence on evapotranspiration, plant water and nutrient uptake and on microbial decomposition. Simulating ecohydrological controls on current and future net ecosystem productivity (NEP) of peatlands thus demands models with coupled soil-plant-atmosphere schemes for gases, water, energy, carbon and nutrients (N, P). We combined a 3-dimensional water transport scheme and prognostic water table dynamics with an existing ecosystem model ecosys in order to examine the hydrological controls on seasonal and interannual variability in NEP of a rich fen in Alberta, Canada. Simulated hourly ecosystem energy and CO2 fluxes along with hourly near surface soil water contents and daily water table depths correlated very well (R2 ~ 0.80) with measurements at the site from 2003 to 2009, during which the water table declined gradually. We compared modeled and measured fluxes at hourly and seasonal time scales in years with contrasting weather and water table depths in order to see how water table fluctuations altered the diurnal and seasonal patterns of NEP. In the model, shallow water tables limited root and soil aeration, slowing root and microbial growth, and hence nutrient uptake. This reduced gross primary productivity (GPP) but also ecosystem respiration (RE), so that the peatland remained a substantial net C sink. In the model, deeper water tables caused more rapid microbial and root growth, and hence more rapid mineralization and nutrient uptake, and hence greater GPP. Deeper water tables also caused near-surface drying which slightly

  20. Una mirada al fenómeno de la violencia escolar en Costa Rica

    Leonel Arias Sandoval

    2009-06-01

    Full Text Available

    Recibido 30 de julio de 2008 • Aprobado 23 de marzo de 2009 • Corregido 20 de abril de 2009

     

    Resumen. En el actual contexto educativo, padres de familia, estudiantes, docentes, medios de comunicación y demás sectores de la sociedad costarricense, manifiestan su preocupación ante el problema de la violencia escolar, fenómeno social que ha venido en aumento en los últimos años. Sus manifestaciones se perciben por medio de conductas de maltrato, intimidación, agresión verbal o física entre jóvenes, y que se construye por medio de prácticas culturales. De ahí que, para comprender este problema, se debe reflexionar acerca de las posibles causas, teniendo en cuenta el contexto en el cual se desarrolla la convivencia social en cada centro educativo. Algunas de las manifestaciones de violencia tienen su origen en la familia, en la comunidad, en la imitación de patrones de conducta y en la influencia de los medios de información de masa. Además, estos comportamientos son potenciados por el modelo curricular vigente, lo que genera resistencia a las normas institucionales.

     

    Abstract. In the current context of education, parents, students, teachers, media and other sectors of Costa Rican society, express concern about the problem of school violence, a social phenomenon that has been increasing in recent years. Its manifestations are perceived by means of abuse behavior, intimidation, verbal or physical abuse among youth, which are constructed through cultural practices. Therefore, to understand this problem, reflection about possible causes is in order, taking into account the context in

  1. Hipertemia durante el fenómeno de el niño, 1997-98

    Jaime Miranda M

    2003-10-01

    Full Text Available Objetivo: Describir el cuadro clínico y la evolución de los casos de síndrome febril presentados durante el fenómeno de "El Niño" de 1997-98, y presentar una revisión de la fisiopatología del cuadro de hipertermia. Material y métodos: Se realizó un estudio descriptivo longitudinal en la ciudad de Chimbote, Ancash. Se definió como caso de síndrome febril: niños menores de 5 años con fiebre refractaria al uso de antipiréticos sin foco aparente de infección. En el análisis posterior se consideraron: apariencia no tóxica, previamente sano, sin foco de infección al examen físico y con examen de laboratorio negativo. Resultados: Fueron estudiados 25 casos (68% varones, 80% con edades entre 5 y 18 meses con un tiempo de enfermedad promedio de 15,17(13,52 días ± desviación stándar (±DS. La mediana de la temperatura fue 38,8ºC con un promedio de 38,84ºC (rango 38 - 40ºC. 68% tuvo un tiempo de enfermedad mayor de 15 días; 52% había visitado al menos una vez un centro médico anterior; 68% recibió antibióticos y antipiréticos; y, 52 % ingresó al hospital por emergencia. Todos los casos presentaron alza térmica, asociado a piel seca (72%, diarrea (64%, tos (52%, baja de peso (52%, irritabilidad (44%, náuseas o vómitos (40%, rinorrea (24% y convulsiones (20%. El tiempo de hospitalización promedio fue 4,7 días y el estado febril promedio fue 2,5 días. Ninguno tuvo examen de laboratorio compatible con causa infecciosa. Conclusiones: En situaciones ambientales adversas debe considerarse al calor ambiental como un factor importante en el desarrollo de la hipertermia, con el propósito de brindar un manejo más apropiado a los afectados en el menor tiempo posible.

  2. Influência dos compostos fenólicos de especiarias sobre a lipoperoxidação e o perfil lipídico de tecidos de ratos Influence of spices phenolic compounds on lipoperoxidation and lipid profile of rats tissues

    Ana Vládia Bandeira Moreira

    2004-12-01

    Full Text Available OBJETIVO: Este trabalho avaliou o efeito antioxidante dos compostos fenólicos de uma mistura de especiarias (mostarda, canela e erva-doce sobre o metabolismo dos ácidos graxos das séries ômega3 e ômega6. MÉTODOS: Ratos Wistar recém desmamados receberam dieta rica em gorduras essenciais e um chá de especiarias. Após 45 dias, os animais foram sacrificados e tiveram seus tecidos coletados para análise das substâncias reativas ao ácido tiobarbitúrico e perfil lipídico. RESULTADOS: O chá fornecido aos animais apresentou atividade antioxidante equivalente ao hidroxitolueno butilado. Foram identificados no chá, os ácidos fenólicos catecol, salicílico e caféico; as enzimas cicloxigenase e lipoxigenase foram inibidas pelos extratos ricos nestes ácidos fenólicos. O perfil de ácidos graxos apresenta diferença entre os grupos teste e controles. Todos os tecidos dos grupos teste apresentaram menores valores em lipoperoxidação, em comparação aos controles. CONCLUSÃO: Estes dados sugerem, portanto, um efeito antioxidante das substâncias fenólicas identificadas na mistura das especiarias, sobre os ácidos graxos das séries ômega3 e ômega6.OBJECTIVE: This work analyzed the influence of the phenolic compounds from a blend of spices (mustard, cinnamon and anise on the omega3 and omega6 fatty acids metabolism. METHODS: Weaned Wistar rats received a diet rich in essencial lipids and an infusion of blended spices for 45 days. After that period, they were sacrificed their tissues were collected and analized for the TBARS and lipid profile by CGMS. RESULTS: The tea of spices showed an antioxidant activity equivalent to that of the butylated hydroxytoluene. The following phenolic acids were identified in the infusion, using mass chromatography: cathecol, salicilic and cafeic; Lipooxygenase and ciclooxigenase enzymes were inhbited by the phenolic acid extracts. It was observed that the total amount of the fatty acids found in the test

  3. Violência como fenômeno intrínseco à cultura política brasileira

    Antonio M. Soares

    2016-06-01

    Full Text Available Este artigo problematiza o conceito de violência e suas mutações através dos tempos. Como fenômeno cultural, a violência é construída na sociedade e se processa de forma a romper com os próprios códigos de ordens produzidos por ela. No caso do Brasil a violência se mostra intrínseca ao processo de formação da sociedade brasileira, estando presente nas lógicas autoritárias e na imposição cultural desde os tempos da colonização. A violência emerge como uma agressão ao indivíduo e ao coletivo, ela aniquila o sentido da política e desabilita o mundo comum. As interpretações presentes neste trabalho buscam aprofundar as análises sobre a violência enquanto fenômeno social e cultural, redimensionando os efeitos que ela produz para a condição humana e suas associações com as dimensões da civilidade, incivilidade e descivilidade. Neste contexto, destacaremos como o fenômeno da violência se afirmou como uma dimensão estrutural e cultural da formação da sociedade brasileira, como ele se revela na contemporaneidade, nos jogos de poder, nas relações de força e no movimento de fronteiras tênues entre o legal e o ilegal.

  4. Sentimentos do adolescente relacionados ao fenômeno BULLYING: possibilidades para a Assistência de Enfermagem nesse contexto

    Agnes Schutz de Oliveira; Priscila da Silva Antonio

    2006-01-01

    O bullying é um fenômeno devastador podendo vir a afetar a auto-estima e a saúde mental dos adolescentes. Geralmente ocorre quando o adolescente é mais suscetível ou vulnerável às agressões verbais ou morais que lhes causam angústia e dor, principalmente quando ocorrido em ambiente escolar traduzindo-se como uma forma de exclusão social. Pode desencadear alguns problemas de saúde tais como a anorexia, bulimia, depressão, ansiedade e até mesmo o suicídio. A enfermagem, pautada com princípios d...

  5. La cultura física y el deporte: fenómenos sociales /Physical culture and sport: social phenomena

    Diana A. Camargo R; Edwin A. Góm; Jonathan Ovalle O; Ricardo Rubiano

    2013-01-01

    La cultura física y el deporte son categorías que se han relacionado con la actividad física y la educación física a lo largo del tiempo, retomando diferentes paradigmas de conocimiento; sin embargo, el paradigma imperante ha sido el empírico-analítico, que reduce la mirada a los fenómenos medibles y observables. Objetivo: identificar las concepciones y enfoques de la cultura física y el deporte en los diferentes momentos de la historia, planteados desde la lógica ...

  6. O fenómeno sinestésico na estruturação do pensamento criativo

    Torrão, Rita Guerreiro, 1979-

    2012-01-01

    A estruturação do pensamento criativo do adolescente apresenta-se de modo “fragmentado”, em parte, devido às caraterísticas da sua experiência sensorial. Propõe-se observar a possibilidade de reconhecimento da perceção humana, segundo o “fenómeno sinestésico”, focalizando metodologias de ensino artístico e conteúdos curriculares na aprendizagem da criatividade. O nosso estudo envolveu um grupo/turma de adolescentes com idades compreendidas entre os quinze e os dezassete anos do...

  7. CO2 exchange of a sedge fen in southern Finland—the impact of a drought period

    Aurela, Mika; Riutta, Terhi; Laurila, Tuomas; Tuovinen, Juha-Pekka; Vesala , Timo; Tuittila, Eeva-Stiina; Rinne, Janne; Haapanala, Sami; Laine, Jukka

    2011-01-01

    Eddy covariance (EC) measurements of net ecosystem CO2 exchange (NEE) were conducted on a boreal sedge fen in southern Finland (61°50′N, 24°12′E) during a 1.5-yr period covering two summers in 2004–2005. The EC data were complemented by chamber measurements, which enabled the partition of the daytime NEE into respiration and photosynthesis. A special emphasis was put on the hydrometeorological responses of CO2 exchange during a drought period in July 2005. A mean CO2 efflux of 0.009 mgCO2 m-2...

  8. Efficient spin-filter and negative differential resistance behaviors in FeN4 embedded graphene nanoribbon device

    Liu, N.; Liu, J. B.; Yao, K. L.; Ni, Y.; Wang, S. L.

    2016-03-01

    In this paper, we propose a new device of spintronics by embedding two FeN4 molecules into armchair graphene nanoribbon and sandwiching them between N-doped graphene nanoribbon electrodes. Our first-principle quantum transport calculations show that the device is a perfect spin filter with high spin-polarizations both in parallel configuration (PC) and antiparallel configuration (APC). Moreover, negative differential resistance phenomena are obtained for the spin-down current in PC, and the spin-up and spin-down currents in APC. These transport properties are explained by the bias-dependent evolution of molecular orbitals and the transmission spectra.

  9. Measurement and modelling of CO2 flux from a drained fen peatland cultivated with reed canary grass and spring barley

    Kandel, Tanka Prasad; Elsgaard, Lars; Lærke, Poul Erik

    2013-01-01

    Cultivation of bioenergy crops has been suggested as a promising option for reduction of greenhouse gas (GHG) emissions from arable organic soils (Histosols). Here, we report the annual net ecosystem exchange (NEE) fluxes of CO2 as measured with a dynamic closed chamber method at a drained fen...... cropping system when looking at the atmospheric CO2 emissions during cultivation. However, in a broader GHG life-cycle perspective, the lower fertilizer N input and the higher biomass yield in bioenergy cropping systems could be beneficial....

  10. Denitrification Activity of a Remarkably Diverse Fen Denitrifier Community in Finnish Lapland Is N-Oxide Limited

    Palmer, Katharina; Horn, Marcus A.

    2015-01-01

    Peatlands cover more than 30% of the Finnish land area and impact N2O fluxes. Denitrifiers release N2O as an intermediate or end product. In situ N2O emissions of a near pH neutral pristine fen soil in Finnish Lapland were marginal during gas chamber measurements. However, nitrate and ammonium fertilization significantly stimulated in situ N2O emissions. Stimulation with nitrate was stronger than with ammonium. N2O was produced and subsequently consumed in gas chambers. In unsupplemented anox...

  11. O fenômeno das drogas e as macro-políticas agências e tratados internacionais

    Telma Elisa Carraro; Silvia Maria Santos Azevedo dos; Rosangela Maria Fenili; Vera Radünz

    2004-01-01

    El artículo trata sobre la cuestión de las macro políticas relacionados al fenómeno de las drogas, procurando la inserción del tema en el escenário internacional. Registra los principales organismos internacionales que se envolucran con el problema, señalando sus historias y sus acciones. Destaca la actuación de la Organización de los Estados Americanos OEA y la formación de la Comisión Interamericana para el Control del Abuso de Drogas CICAD, integrada por los Estados miembr...

  12. Estudio del fenómeno Social Media en la media empresa del sector TIC español

    Muñoz Fernández, Víctor

    2014-01-01

    Con el paso de los años, el fenómeno Social Media ha adquirido una mayor importancia entre las empresas, gracias a las posibilidades que les ofrece. Este proyecto está basado en: - En primer lugar, elaborar un estudio teórico con el que se pretende entender el empleo que hace la empresa en general de la Web 2.0. - En segundo lugar, elaborar un estudio práctico con el que se pretende conocer el uso y consecuencias que están logrando las medianas empresas del sector TIC español, gracia...

  13. La etimología popular como fenómeno peculiar de motivación del lenguaje

    2010-01-01

    La etimología popular, a pesar de carecer de un tratamiento estrictamente riguroso y clarificador, constituye un importante mecanismo regenerador del léxico. Su incidencia en la competencia lingüística de los hablantes, así como su particular modo de actuación, nos ha llevado a iniciar una incursión en este ámbito. Si partimos de una nueva perspectiva realista acerca del lenguaje, haciendo hincapié en su naturaleza social, el estudio de este fenómeno se convierte en un elemento esencial a la ...

  14. Comparison of phenol content and antioxidant capacity of nuts Comparação entre o conteúdo de fenólicos e capacidade antioxidante de sementes

    Lucile Tiemi Abe

    2010-05-01

    Full Text Available Frequent nut intake is associated with protective effects against cardiovascular diseases. In addition to the generally high contents of unsaturated fatty acids, polyphenol compounds seem to be also implicated in health promoting effects of nuts due to their antioxidant properties. In this way, eleven different kinds of nuts, including pinhao seeds (Araucaria angustifolia and Brazil nuts (Bertholletia excelsa, typical of Brazil, were analyzed for the content of phenol compounds, including the potent anti-mutagenic and anti-cancer ellagic acid, and antioxidant capacity of methanolic extracts. The antioxidant capacity varied a hundred times among the different nuts, from 1.2 to 120 mg of Trolox equivalents.100 g-1 (FW. Total ellagic acid was determined after acid hydrolysis of ellagitannins and ellagic acid glycosides, and it was detected in only 3 of the 11 samples. The content of free and total ellagic acid in nuts varied from 0.37 to 41 and from 149 (chestnuts to 823 (walnuts mg.100 g-1 (FW, respectively. Among nuts, samples with the highest contents of ellagic acid (walnuts and pecans also presented the highest total phenol contents and DPPH radical scavenging capacities. Pinhao seeds and Brazil nuts did not present significant amounts of phenols nor antioxidant capacity.O consumo frequente de nozes está associado a efeitos protetores contra doenças cardiovasculares. Além do alto teor de ácidos graxos insaturados, os compostos polifenólicos também parecem implicados nos efeitos promotores da saúde devido a suas propriedades antioxidantes. Desta forma, onze tipos de nozes/sementes, incluindo pinhão (Araucaria angustifolia e castanha-do-pará (Bertholletia excelsa, típicos do Brasil, foram analisados em relação ao seu conteúdo de fenólicos, incluindo ácido elágico, tido como potente antimutagênico e anticancerígeno, e capacidade antioxidante dos extratos metanólicos. A capacidade antioxidante variou cem vezes entre as

  15. Metódica: Articulación sistema teórico, fenómeno y procesos en el objeto de estudio. Una perspectiva desde el fenómeno pobreza

    Yajaira Jiménez Zabala

    2011-10-01

    Full Text Available En este artículo discutimos la visión metódica que toma como apoyo el pivote entre lo cualitativo, lo cuantitativo y el orden de complejidad, en un enfoque plurimetódico, a través del cual se construyó la visión de la pobreza como objeto de estudio. Tal selección, está justificada en tanto se entiende la pobreza como un fenómeno social complejo, por las diversas aristas que le identifican. La combinación de los enfoques metodológicos permitió la aprehensión de los diferentes aspectos del fenómeno y de sus interrelaciones en las representaciones de los actores sociales vinculados con el estudio. Lo cualitativo, se entiende como la simbiosis de prácticas interpretativas, que no privilegia una metodología sobre otra. Lo cuantitativo estuvo referido al uso de indicadores derivados de los soportes referenciales del problema; el orden de complejidad, atendió a la manifestación de lo simple en tanto nodo tensional complejo, que requiere una mirada diferente para su comprensión e interpretación.

  16. El fenómeno del acoso laboral entre los trabajadores de la universidad O fenômeno mobbing entre os trabalhadores da universidade The phenomenon of mobbing among university employees

    Fernando Justicia Justicia

    2007-12-01

    Full Text Available El objetivo del artículo es realizar una descripción del fenómemo mobbing -acoso laboral- en el contexto de la universidad. Los trabajos realizadossobre este problema no son muy prolíficos lo que puede explicar la gran dificultad para caracterizar el fenómeno en el ámbito universitario. En el presente trabajo presentamos los niveles de incidencia del acoso laboral entre la población universitaria, los tipos de acoso más frecuentes y los efectos producidos en las víctimas, con la finalidad de caracterizar y definir el problema. Al mismo tiempo, intentamos conocer la influencia de determinadas variables como la edad, género y tiempo de victimización. En este sentido, y de acuerdo con otros estudios realizados, encontramos diferencias estadísticas en función del género de las víctimas. Del mismo modo, los resultados apuntan que la frecuencia y duración del acoso laboral afectan negativamente a las víctimas provocando un empeoramiento de los efectos derivados del acoso.O objetivo deste artigo é realizar uma descrição do fenômeno mobbing -tormento e persecução no lugar do trabalho- no contexto da universidade. Há poucos trabalhos realizados sob este problema nos contextos de educação superior o que pode explicar a grande dificuldade para caracterizar o fenômeno no âmbito universitário. Neste artigo apresentamos os níveis de incidência entre a população universitária, os tipos de mobbing mais freqüentes e os efeitos produzidos nas vítimas com a finalidade de caracterizar e definir o problema. Ao mesmo tempo, tentamos conhecer a influência de determinadas variáveis tais como a idade, gênero ou o tempo de exposição ao fenômeno. Neste sentido, e em concordância com outros estudos realizados, encontramos diferenças estatísticas em função do gênero das vítimas. De igual forma, os dados apontam que a freqüência e duração da situação de persecução no trabalho afetam negativamente as vítimas provocando

  17. Selective inhibition of jasmonic acid accumulation by a small α, β-unsaturated carbonyl and phenidone reveals different modes of octadecanoid signalling activation in response to insect elicitors and green leaf volatiles in Zea mays

    Engelberth Jurgen

    2011-10-01

    Full Text Available Abstract Background Plants often release a complex blend of volatile organic compounds (VOC in response to insect herbivore damage. Among those blends of VOC green leaf volatiles (GLV have been demonstrated to function as defence signals between plants, thereby providing protection against impending herbivory. A problem in understanding the mode of action of these 6-carbon aldehydes, alcohols, and esters is caused by their structural diversity. Besides different degrees of oxidation, E-2- as well as Z-3-configured isomers are often released. This study was therefore initiated to determine the structural requirement necessary to exhibit biological activity measured as jasmonic acid (JA accumulation in Zea mays seedlings. Findings The structure/function analysis of green leaf volatiles and related compounds revealed that an olefinic bond in position 2 or 3 and a size of 6-8 carbons is required for biological activity in maize. Also, it was found that the presence of an α, β-unsaturated carbonyl is not a prerequisite for activity. However, by treating plants first with volatile acrolein it was discovered that this smallest α, β-unsaturated carbonyl inhibits JA accumulation in response to insect elicitor treatment, but not after GLV exposure. This selective inhibitory effect was also found for phenidone, an inhibitor of lipoxygenases. These findings led to the discovery of a pool of protein-associated 12-oxo-phytodienoic acid, a biosynthetic precursor of JA, which appeared to be rapidly converted into JA upon exposure to GLV. Conclusions The structure/function analysis of GLV demonstrates a high degree of correlation between the compounds released by wounded plants in nature and their biological activity. The selective inhibitory effects of acrolein and phenidone on insect elicitor- and GLV-induced JA accumulation in maize led to the discovery of a pool of protein-associated precursor, which is rapidly activated and transformed to JA after

  18. Measurement of 55Fe(n ,p ) cross sections by the surrogate-reaction method for fusion technology applications

    Pandey, Bhawna; Desai, V. V.; Suryanarayana, S. V.; Nayak, B. K.; Saxena, A.; Mirgule, E. T.; Santra, S.; Mahata, K.; Makawana, R.; Abhangi, M.; Basu, T. K.; Rao, C. V. S.; Jakhar, S.; Vala, S.; Sarkar, B.; Agrawal, H. M.; Kaur, G.; Prajapati, P. M.; Pal, Asim; Sarkar, D.; Kundu, A.

    2016-02-01

    We have measured the proton decay probabilities of the *56Fe and *47Ti compound systems which are populated by the transfer reactions 52Cr(6Li,d ) *56Fe (surrogate of n +55Fe→*56Fe→p +55Mn ) and 45Sc(6Li,α ) *47Ti (surrogate of n +46Ti→47Ti*→p +46Sc ) reactions, respectively. The 55Fe(n ,p ) cross sections were then obtained in the equivalent neutron energy range of 7.9 to 20.1 MeV within the framework of the surrogate-reaction method. The measured results were compared with predictions of the empire-3.2.3 statistical model code and various recent evaluated data libraries. The experimental cross-section data on 55Fe(n ,p ) are in reasonable agreement with EAF-2010, while the TENDL-2014 and ROSFOND-2010 data show some discrepancies. This study demonstrates the possibility of determining neutron-induced charged particle emission cross sections for unstable radionuclides relevant to fusion technology applications by the surrogate-reaction method.

  19. El fenómeno Fujimori y la crisis política en el Perú

    Eduardo BUENO LEÓN

    2009-11-01

    Full Text Available RESUMEN: En el presente trabajo, se analizan las causas que determinan el fenómeno Fujimori en la coyuntura electoral de 1989- 90. Se plantea la tesis que la "Fujimorización" se produce al confluir tendencias sociales democratizadoras y políticamente excluídas con un generalizado rechazo popular al estamento político. El fenómeno "integra" estas variables y desarticula la escena electoral que se presentaba artificialmente definida. Se plantea de esta forma, la posibilidad de la relegitimación del escenario político peruano y la afirmación autónoma de nuevos actores sociales y políticos.ABSTRACT: In this article, the author studies the causes which determined the phenomenon "Fujimori" in Peru in the 1989-90 elections. The main thesis is that "Fujimorización" arised in a context where different social democratic and politically excluded tendencies gathered with a popular rejection to the political class. This phenomenon "integrated" these variables and it produced a desarticulation of the electoral scene which was presented as artificially defined. In the new context it is posible to relegitimate the Perurian political scene and the autonomous assert of the new social and political actors.

  20. Cyberbullying: percepções acerca do fenômeno e das estratégias de enfrentamento

    Sidclay Bezerra Souza

    2014-01-01

    Full Text Available O cyberbullying, caracterizado como um dos tipos de violência em contexto educativo, apresenta-se como uma das principais causas do mal-estar vivido por seus protagonistas. O estudo inserido no Projeto Cyberbullying - o diagnóstico da situação em Portugal pretendeu compreender o fenômeno a partir das vivências de 118 estudantes do primeiro ano do Ensino Superior público português, que responderam a um questionário. Pudemos perceber a percepção dos alunos sobre o fenômeno e a importância que pares, professores e pais apresentam no enfrentamento e prevenção do cyberbullying. Tais resultados orientam-se no sentido do desenvolvimento sistêmico de comunidades que se fortalecem internamente para que cada um se sinta autorizado a intervir e a cuidar dos que nelas são vítimas de violência.

  1. Mechanism of formation of Fe-N alloy in the solid-state reaction process between iron and boron nitride

    Processes and resulting products of solid-state reaction between Fe and hexagonal boron nitride (h-BN) were studied by ball milling a mixture of Fe and h-BN with an Fe to h-BN volume ratio of 1:12.5 and/or heat-treating under normal or high pressure. The 30 h-milled mixture was annealed for 1 h under an atmospheric pressure at 770 and 1170 K, respectively. A small amount of γ'-Fe4N was observed in the mixture annealed at 770 K and a little γ-Fe(N) was obtained at 1170 K. All Fe atoms in the mixture reacted with N atoms in the BN to form a single phase of ε-FexN when the mixture was milled for 60 h or annealed for 1 h under 4 GPa at temperatures of 690-800 K. However, no Fe-B phase was observed in the present experiment. Formation and phase transition of Fe-N alloy in the solid-state reaction process as well as effect of pressure on the reaction and resulting products are discussed in the present paper. The mechanism of formation of Fe-N and Fe-B alloys in the reaction processes are also investigated in terms of the Miedema model and thermodynamics and kinetics

  2. Algumas reflexões para estabelecer a cronologia do "fenômeno transexual" (1910-1995

    Pierre-Henri Castel

    2001-01-01

    Full Text Available O "fenômeno transexual" (Benjamin é um indicador muito seguro das modificações históricas da percepção científica, mas também cultural e política da identidade sexual no século XX. Para apresentar uma cronologia e uma bibliografia escolhida desse fenômeno, este artigo propõe um fio condutor: a recusa sistemática das interpretações psicanalíticas do transexualismo pelos sexólogos, endocrinologistas e sociólogos que estudaram o problema.The "Transsexual Phenomenon" (Benjamin is a reliable index of the historical modifications of scientific, cultural and political perception of sexual identity in the 20th century. As an introduction to a chronology and selected bibliography of this phenomenon, I suggest a clue: the systematic denial of the relevance of psychoanalytic explanations of transsexualism by all the biologists, endocrinologists and sociologists who dealt with the problem.

  3. Three-phase succession of autochthonous lactic acid bacteria to reach a stable ecosystem within 7 days of natural bamboo shoot fermentation as revealed by different molecular approaches.

    Romi, Wahengbam; Ahmed, Giasuddin; Jeyaram, Kumaraswamy

    2015-07-01

    Microbial community structure and population dynamics during spontaneous bamboo shoot fermentation for production of 'soidon' (indigenous fermented food) in North-east India were studied using cultivation-dependent and cultivation-independent molecular approaches. Cultivation-dependent analyses (PCR-amplified ribosomal DNA restriction analysis and rRNA gene sequencing) and cultivation-independent analyses (PCR-DGGE, qPCR and Illumina amplicon sequencing) were conducted on the time series samples collected from three independent indigenous soidon fermentation batches. The current findings revealed three-phase succession of autochthonous lactic acid bacteria to attain a stable ecosystem within 7 days natural fermentation of bamboo shoots. Weissella spp. (Weissella cibaria, uncultured Weissella ghanensis) and Lactococcus lactis subsp. cremoris predominated the early phase (1-2 days) which was joined by Leuconostoc citreum during the mid-phase (3 days), while Lactobacillus brevis and Lactobacillus plantarum emerged and became dominant in the late phase (5-7 days) with concurrent disappearance of W. cibaria and L. lactis subsp. cremoris. Lactococcus lactis subsp. lactis and uncultured Lactobacillus acetotolerans were predominantly present throughout the fermentation with no visible dynamics. The above identified dominant bacterial species along with their dynamics can be effectively utilized for designing a starter culture for industrialization of soidon production. Our results showed that a more realistic view on the microbial ecology of soidon fermentation could be obtained by cultivation-dependent studies complemented with cultivation-independent molecular approaches. Moreover, the critical issues to be considered for reducing methodological biases while studying the microbial ecology of traditional food fermentation were also highlighted with this soidon fermentation model. PMID:25963776

  4. Effects of a blend of essential oil compounds and benzoic acid on performance of broiler chickens as revealed by a meta-analysis of 4 growth trials in various locations.

    Weber, G M; Michalczuk, M; Huyghebaert, G; Juin, H; Kwakernaak, C; Gracia, M I

    2012-11-01

    A series of growth trials with broiler chicks was conducted in various geographical locations to evaluate the efficacy of a novel eubiotic feed additive (EFA) at various dietary inclusion levels on performance of growing chicks. The EFA product consisted of a blend of essential oil compounds (thymol, eugenol, piperine) with benzoic acid, all belonging to the group of flavoring substances. Although variable in responses, the overall results indicated that 300 mg/kg of this EFA represented an optimum supplementation dose for generation of beneficial performance effects in broilers. A meta-analysis with all data from the 300 mg/kg EFA-supplemented treatments in comparison with the non-supplemented controls revealed that the eubiotic product significantly improved BW on d 21 (+2.0%; P = 0.0021) and on d 42 (+1.4%; P = 0.0151). Furthermore, the birds on the EFA 300 mg/kg treatment expressed a higher average daily gain in the starter phase (d 1-21; +2.1%; P = 0.0023) and over the entire experimental period (d 1-42; +1.5%; P = 0.0154). Feed conversion ratio was more favorable with dietary EFA supplementation (-0.6%; P = 0.0414), when compared with the control birds. Mortality was considered normal and was not affected by the dietary treatment (control = 3.09%; EFA 300 mg/kg = 3.26%). In conclusion, 300 mg/kg of this new eubiotic product demonstrated to effectively improve performance of broiler chicks under various husbandry conditions. PMID:23091138

  5. Assessment of CD4+ T cell responses to glutamic acid decarboxylase 65 using DQ8 tetramers reveals a pathogenic role of GAD65 121-140 and GAD65 250-266 in T1D development.

    I-Ting Chow

    Full Text Available Susceptibility to type 1 diabetes (T1D is strongly associated with MHC class II molecules, particularly HLA-DQ8 (DQ8: DQA1*03:01/DQB1*03:02. Monitoring T1D-specific T cell responses to DQ8-restricted epitopes may be key to understanding the immunopathology of the disease. In this study, we examined DQ8-restricted T cell responses to glutamic acid decarboxylase 65 (GAD65 using DQ8 tetramers. We demonstrated that GAD65 121-140 and GAD65 250-266 elicited responses from DQ8+ subjects. Circulating CD4+ T cells specific for these epitopes were detected significantly more often in T1D patients than in healthy individuals after in vitro expansion. T cell clones specific for GAD65 121-140 and GAD65 250-266 carried a Th1-dominant phenotype, with some of the GAD65 121-140-specific T cell clones producing IL-17. GAD65 250-266-specific CD4+ T cells could also be detected by direct ex vivo staining. Analysis of unmanipulated peripheral blood mononuclear cells (PBMCs revealed that GAD65 250-266-specific T cells could be found in both healthy and diabetic individuals but the frequencies of specific T cells were higher in subjects with type 1 diabetes. Taken together, our results suggest a proinflammatory role for T cells specific for DQ8-restricted GAD65 121-140 and GAD65 250-266 epitopes and implicate their possible contribution to the progression of T1D.

  6. Activation of the jasmonic acid pathway by depletion of the hydroperoxide lyase OsHPL3 reveals crosstalk between the HPL and AOS branches of the oxylipin pathway in rice.

    Xiaoqiang Liu

    Full Text Available The allene oxide synthase (AOS and hydroperoxide lyase (HPL branches of the oxylipin pathway, which underlie the production of jasmonates and aldehydes, respectively, function in plant responses to a range of stresses. Regulatory crosstalk has been proposed to exist between these two signaling branches; however, there is no direct evidence of this. Here, we identified and characterized a jasmonic acid (JA overproduction mutant, cea62, by screening a rice T-DNA insertion mutant library for lineages that constitutively express the AOS gene. Map-based cloning was used to identify the underlying gene as hydroperoxide lyase OsHPL3. HPL3 expression and the enzyme activity of its product, (E-2-hexenal, were depleted in the cea62 mutant, which resulted in the dramatic overproduction of JA, the activation of JA signaling, and the emergence of the lesion mimic phenotype. A time-course analysis of lesion formation and of the induction of defense responsive genes in the cea62 mutant revealed that the activation of JA biosynthesis and signaling in cea62 was regulated in a developmental manner, as was OsHPL3 activity in the wild-type plant. Microarray analysis showed that the JA-governed defense response was greatly activated in cea62 and this plant exhibited enhanced resistance to the T1 strain of the bacterial blight pathogen Xanthomonasoryzaepvoryzae (Xoo. The wounding response was attenuated in cea62 plants during the early stages of development, but partially recovered when JA levels were elevated during the later stages. In contrast, the wounding response was not altered during the different developmental stages of wild-type plants. These findings suggest that these two branches of the oxylipin pathway exhibit crosstalk with regards to biosynthesis and signaling and cooperate with each other to function in diverse stress responses.

  7. Okadaic acid

    Danielsen, E Michael; Hansen, Gert H; Severinsen, Mai C K

    2014-01-01

    Okadaic acid (OA) is a polyether fatty acid produced by marine dinoflagellates and the causative agent of diarrhetic shellfish poisoning. The effect of OA on apical endocytosis in the small intestine was studied in organ cultured porcine mucosal explants. Within 0.5-1 h of culture, the toxin caused...... endosomes (TWEEs) occurred unimpeded in the presence of OA, FM condensed in larger subapical structures by 1 h, implying a perturbed endosomal trafficking/maturation. The fluorescent lysosomotropic agent Lysotracker revealed induction of large lysosomal structures by OA. Endocytosis from the brush border...

  8. Distribution change of oxygen vacancies in layered perovskite type(Sr, La)n+1FenO3n+1 (n=3)

    To elucidate characteristic oxygen vacancy formation in layered perovskite (Sr, La)n+1FenO3n+1 with the perovskite layer number: n=3, oxygen vacancy content δ of the (Sr0.775La0.225)4Fe3O10−δ (SLF4310) was investigated using a titration technique and a thermogravimetric analysis. The equilibrium constant K for the reduction reaction: Oo×+2FeFe∙ (Fe4+)=1/2O2+Vo∙∙+2FeFe×(Fe3+) was estimated using the vacancy content δ. The Arrhenius plot of the K reveals slope change at approximately 775 °C. From the Rietveld analysis, the oxygen vacancies are the most remarkable at the O2 (O4) sites at lower (higher) temperatures than about 800 °C, which temperature is approximately comparable with that of slope change in the K. These facts mean that distribution of vacancy sites in the SLF4310 changes at approximately 775 °C, accompanying no structural phase transition. The vacancy distribution change affects to the ion conductivity of the SLF4310. - Graphical abstract: Crystal structure of (Sr0.775La0.225)4Fe3O10−δ (SLF4310) at 1000 °C. Display Omitted - Highlights: • Distribution change of oxygen vacancies is appeared at approximately 775 °C. • The distribution change with no structure phase transition is the first observation. • The vacancy distribution change affects the ion conductivity of the SLF4310

  9. Compuestos fenólicos del grano de maíz y su relación con el oscurecimiento de masa y tortilla

    Yolanda Salinas Moreno; José de J. López Reynoso; Guadalupe B. González Flores; Gricelda Vázquez Carrillo

    2007-01-01

    Algunos de los híbridos y variedades de maíz cultivados en el Estado de México producen masa y tortilla que se oscurecen. No se conoce la causa de este oscurecimiento, pero los compuestos fenólicos del grano podrían estar involucrados. Los objetivos del presente estudio fueron determinar si el contenido de compuestos fenólicos en el grano de maíz está relacionado con el oscurecimiento de masa y tortilla en los maíces evaluados, y obtener el perfil de ácidos fenólicos en muestras de maíz cuya ...

  10. La definición jurídica del fenómeno metropolitano en el ámbito subnacional mexicano

    Alberto Arellano Ríos

    2014-01-01

    En este texto se analiza la definición jurídica del fenómeno metropolitano en seis Estados de la república mexicana. Se estudian seis legislaciones estatales creadas expresamente para atender y darle forma jurídica a un problema que se ha acentuado con mayor fuerza en México, el cual desde el punto de vista de las instancias gubernamentales tiene mayor relevancia en los últimos veinte años. De este modo, el documento esboza el fenómeno metropolitano como contexto social. Lue...

  11. Comprensión de fenómenos naturales desde la perspectiva científica desde el contexto ecosistemas

    Zepeda Navarrete, José Alejandro; Zacarías Pérez, Patricia; Ramírez Ponce, Ramón; Martínez Díaz, Francisco René; Reyes Matias, Danilka

    2012-01-01

    • Información General • Evaluación Diagnóstica • Contenido o Tema 1 - ¿Qué significa la competencia comprensión de fenómenos y procesos naturales desde la perspectiva científica en el contexto de los ecosistemas?  Objetivos específicos del tema  Actividad inicial del tema  Desarrollo del tema  Actividad final del tema  Recursos adicionales o Tema 2 - ¿Por qué es relevante que adquiera la competencia comprensión de fenómenos y procesos naturales desde la perspec...

  12. La Interacción Mutua entre Fuentes y las Aparentes Anomalías en el Fenómeno de Interferencia

    Reinaldo Welti

    2002-01-01

    En la mayoría de los textos de física del nivel básico universitario al tratar el fenómeno de interferencia suponen que las fuentes irradian de la misma forma cualquiera sea la distancia entre ellas. En algunas situaciones esta suposición puede llevar a aparentes anomalías en la conservación de la energía. En este trabajo se muestra que estas anomalías se resuelven solamente si el fenómeno de interferencia se presenta en un contexto que tenga en cuenta las interacciones entre las fuentes y el...

  13. Análisis preeliminar de carotenoides y compuestos fenólicos en frutos de zapote mamey (Pouteria sapota (Jacq.) H.E. Moore & Stearn)

    R. M. Soto-Hernández; I. Alia-Tejacal; M. T. Colinas-León; M. T. Martínez-Damián

    2005-01-01

    La pulpa del fruto de zapote mamey contiene cantidades considerables de carotenoides y compuestos fenólicos, recientemente el consumo de estos metabolitos se han asociado con la disminución de enfermedades cardiovasculares y cáncer. Por otra parte, los fenoles están relacionados con el oscurecimiento de la pulpa lo cual disminuye la vida poscosecha del fruto. El presente estudio tuvo como objetivo realizar un análisis de los carotenoides y compuestos fenólicos presentes en la pulpa del fruto ...

  14. Estudio de la biodegrabilidad de mezclas de compuestos fenólicos alquil-sustituidos bajo condiciones de metanogénesis

    Meza Vudoyra, Miguel Angel

    2013-01-01

    Con el objetivo de evaluar la biodegradabilidad de compuestos fenólicos, en sistemas continuos y en lotes, bajo condiciones de metanogénesis, utilizando diversas mezclas y determinar las velocidades específicas de biodegradación de los compuestos alquil-fenólicos, se investigó el efecto del orto y meta-cresol sobre la biodegradabilidad del fenol y para-cresol, utilizando lodo granular metano génico adaptado. Se utilizaron dos reactores continuos tipo UASB y botellas serológicas en las que se ...

  15. The preferential growth of branched GDGT source microorganisms under aerobic conditions in peat revealed by stable isotope probing experiments

    Huguet, Arnaud; Meador, Travis B.; Laggoun-Défarge, Fatima; Könneke, Martin; Derenne, Sylvie; Hinrichs, Kai-Uwe

    2016-04-01

    fen, whereas corresponding rates in the anaerobic acrotelm incubations were more than an order of magnitude slower (rates of bacterial fatty acids approached or exceeded 1 μg cm‑3 y‑1 in both aerobic and anaerobic incubations, and were therefore much higher than those of brGDGTs. This suggests that the brGDGT producers are a minor constituent of the microbial community in Sphagnum-dominated peatlands or brGDGTs are a small component of the microbial cell membrane in comparison to fatty acids, despite the typically high brGDGT concentrations observed in peat. In conclusion, our results reveal that brGDGT source microorganisms preferentially grow under oxic to sub-oxic conditions, likely as facultative anaerobes. We show for the first time that these microorganisms are especially active at the peat surface, in contrast to the deeper layers, implying that the high abundance of brGDGTs observed in the catotlem should result from the accumulation of the brGDGTs actively produced in the acrotelm. Reference Weijers, J.W.H., Wiesenberg, G.L.B., Bol, R., Hopmans, E.C., Pancost, R.D., 2010. Biogeosciences 7, 2959-2973.

  16. Greenhouse gas emissions from a drained fen peatland cultivated with reed canary grass for biogas production

    Kandel, T.P.

    2013-10-01

    Cultivated peatlands are significant sources of CO{sub 2} as the drainage and subsequent agricultural practices such as tillage and fertilization enhances the decomposition of soil organic carbon. However, use of the peatlands for perennial energy crop production could help to reduce the CO{sub 2} emissions as annual ploughing is avoided in perennial cropping systems and fertilizer requirements is also lower compared to annual arable crops. However, crop managements such as fertilization and harvesting of those energy crops are also important in respect to total GHG balance. Moreover, economical viability of energy crop production in peatland need to be considered which requires studies on best management practices to produce high biomass and energy per hectare of land with as little input of resources as possible. In the first study, annual net ecosystem balance of CO{sub 2} from a riparian fen peatland used for annual arable crop and perennial energy crop cultivation was compared. Fluxes of CO{sub 2} were measured with closed chambered methods which were later partitioned into light depended gross photosynthesis (GP) and light independent ecosystem respiration (R{sub E}). The annual flux of CO{sub 2} was estimated by modelling GP and R{sub E} separately and extrapolating the obtained parameters in relation to environmental and biomass measurements. Model performances of commonly used GP and R{sub E} models were enhanced by introducing ratio vegetation index (RVI) as proxy for active leaf area index. Both GP and R{sub E} showed strong seasonal pattern as expected. An expected higher annual GP was observed in the RCG cultivation system which was favored by a longer growth period, but R{sub E} was also higher which was mainly contributed by higher plant respiration. Annual net ecosystem exchange (NEE) of CO{sub 2} was close to zero for both cropping systems and thus no apparent advantage of the energy cropping system was observed during crop cultivation. Another

  17. The Fatty Acid Profile Analysis of Cyperus laxus Used for Phytoremediation of Soils from Aged Oil Spill-Impacted Sites Revealed That This Is a C18:3 Plant Species.

    Noemí Araceli Rivera Casado

    Full Text Available The effect of recalcitrant hydrocarbons on the fatty acid profile from leaf, basal corm, and roots of Cyperus laxus plants cultivated in greenhouse phytoremediation systems of soils from aged oil spill-impacted sites containing from 16 to 340 g/Kg total hydrocarbons (THC was assessed to investigate if this is a C18:3 species and if the hydrocarbon removal during the phytoremediation process has a relationship with the fatty acid profile of this plant. The fatty acid profile was specific to each vegetative organ and was strongly affected by the hydrocarbons level in the impacted sites. Leaf extracts of plants from uncontaminated soil produced palmitic acid (C16, octadecanoic acid (C18:0, unsaturated oleic acids (C18:1-C18:3, and unsaturated eichosanoic (C20:2-C20:3 acids with a noticeable absence of the unsaturated hexadecatrienoic acid (C16:3; this finding demonstrates, for the first time, that C. laxus is a C18:3 plant. In plants from the phytoremediation systems, the total fatty acid contents in the leaf and the corm were negatively affected by the hydrocarbons presence; however, the effect was positive in root. Interestingly, under contaminated conditions, unusual fatty acids such as odd numbered carbons (C15, C17, C21, and C23 and uncommon unsaturated chains (C20:3n6 and C20:4 were produced together with a remarkable quantity of C22:2 and C24:0 chains in the corm and the leaf. These results demonstrate that weathered hydrocarbons may drastically affect the lipidic composition of C. laxus at the fatty acid level, suggesting that this species adjusts the cover lipid composition in its vegetative organs, mainly in roots, in response to the weathered hydrocarbon presence and uptake during the phytoremediation process.

  18. Síntese de derivados de ácidos fenólicos e estudo da sua actividade antioxidante

    Reis, Bruno Miguel Macedo da Silva

    2008-01-01

    A peroxidação lipídica, além de causar sérios danos no corpo humano, é a principal causa da deterioração dos alimentos afectando a sua cor, aroma e valor nutricional, o que conduz a uma diminuição do seu ciclo de vida. O fenómeno de oxidação pode ser retardado com recurso a antioxidantes, de origem natural ou sintética, que inibam a formação de espécies reactivas, ou que reajam com estas, formando posteriormente radicais com menor grau de reactividade. Nesta dissertação proc...

  19. El tratamiento de fenómenos físicos para aprender matemáticas

    Cortés, Gildardo; Ramírez, Pericles

    2005-01-01

    La historia de la ciencia muestra la íntima relación entre la física y la matemática y cómo en nuestros días esta relación, en el ambiente escolar, se ha ido perdiendo. Nuestro planteamiento intenta recuperar el papel de la experimentación en el aula. Proponemos diseños de aprendizaje basados en prácticas de modelación de fenómenos físicos, para que alumnos construyan conocimientos con significado. En el documento damos evidencia de cómo este planteamiento puede ser posible. La investigación ...

  20. El fenómeno de las redes sociales y los cambios en la vigencia de los Derechos Fundamentales

    Gil Antón, Ana María

    2012-01-01

    Este trabajo aborda, de manera sintética, uno de los problemas más relevantes con los que nos estamos encontrando en el Siglo XXI resultado del fenómeno de Internet, el de las redes sociales que constituyen vías consolidadas de relación e interacción cotidianas, no sólo de las nuevas generaciones de adolescentes y jóvenes, sino también de todo el conjunto de nuestra sociedad. Y pese a que la utilización de las nuevas Tecnologías de la Información y Comunicación ofrece gra...

  1. Greenhouse gas emissions of drained fen peatlands in Belarus are controlled by water table, land use, and annual weather conditions

    Burlo, Andrei; Minke, Merten; Chuvashova, Hanna; Augustin, Jürgen; Hoffmann, Mathias; Narkevitch, Ivan

    2014-05-01

    Drainage of peatlands causes strong emission of the greenhouse gases (GHG) CO2 and N2O, sometimes combined with a weak CH4 uptake. In Belarus drained peatlands occupy about 1505000 ha or more than 7.2 % of the country area. Joosten (2009) estimates CO2 emission from degraded peatlands in Belarus as 41.3 Mt yr-1 what equals to 47 % of total anthropogenic greenhouse gases (GHGs) emission of country in 2011. However, it could not be checked if these numbers are correct since there are no GHG measurements on these sites up to now. Therefore we studied the GHG emissions with the closed chamber approach in four peatlands situated in central and southern Belarus over a period from August 2010 to August 2012. The measurements comprised eight site types representing different water level conditions, and ranging from grassland and arable land over abandoned fields and peat cuts to near-natural sedge fens. Fluxes of CH4 and N2O were determined using the close-chamber approach every second week in snow free periods and every fourth week during winter time. The annual emissions were calculated based on linear interpolation. Carbon dioxide exchange was measured with transparent and opaque chambers every 3-4 weeks and the annual net ecosystem exchange (NEE) was modeled according to Drösler (2005). Most of the drained sites were sources of CO2 in both years. NEE increased with lower mean annual water table level. The highest NEE value (1263.5 g CO2-C m-1yr-1) was observed at the driest site of the study; an abandoned fen formerly used for agriculture. In contrast, a former peat extraction site with moist peat and small Pinus sylvestris tress were sinks of CO2 with uptake to 389.6 g CO2-C m-1yr-1. The highest N2O emissions were recorded at a drained agricultural fen with mean annual rates of up to 2347 mg N2O-N m-2 yr-1. Significant fluxes of CH4 (15 g CH4C m-2 h-1) were observed only at the near-natural site in the first year of investigation when precipitation and the mean water

  2. "Vue de la fenêtre" ou "panorama épique" : structures rhétoriques et fonctions narratives

    Martin, Jean-Pierre

    2014-01-01

    EVOQUANT les "éléments d'une 'scénologie' qui appartient au style général de l'épopée, riche en lieux communs et en formules fixes", J. Frappier relève "un motif fréquent", celui du "panorama épique : du sommet d'une tour, de la fenêtre d'une chambre haute (solier), de la salle située à l'étage d'un château, des personnages regardent l'approche de l'invasion sarrasine, la terre ravagée, les incendies, les massacres, ou la venue d'un messager, ou l'arrivée des secours espérés". A. Iker-Gittlem...

  3. Comparación del contenido fenólico, capacidad antioxidante y actividad antiinflamatoria de infusiones herbales comerciales Comparison of phenolic content, antioxidant capacity and anti-inflamatory activity of commercial herbal infusions

    Erika Elizabeth Muñoz-Velázquez

    2012-06-01

    Full Text Available En la actualidad, hay un incremento en el consumo de infusiones debido a sus propiedades benéficas, las cuales se atribuyen a la presencia de compuestos fenólicos. Por lo anterior, el objetivo de este estudio fue evaluar el contenido fenólico, la capacidad antioxidante y la actividad antiinflamatoria de infusiones comerciales de hierbabuena (Mentha piperita L., limón (Cymbopogon citratos, manzanilla (Matricaria chamomilla L., árnica (Heterotheca inuloides y boldo (Peumus boldus Molina obtenidas en un supermercado en 2009. El contenido de fenoles y la capacidad antioxidante se determinaron por técnicas espectrofotométricas. Adicionalmente, la identificación y cuantificación de compuestos fenólicos también se llevó a cabo por HPLC. La actividad antiinflamatoria se evaluó mediante la inhibición de la enzima ciclooxigenasa-2 (COX-2. La infusión de boldo presentó el mayor contenido de compuestos fenólicos y la mayor capacidad antioxidante medida por la técnicas ABT, seguida de las infusiones de hierbabuena por el m��todo de FRAP. En las infusiones evaluadas se identificaron diez diferentes compuestos, encontrándose en mayor concentración los compuestos catequina, epigalocatequina galato, ácido rosmarínico y eriocitrina. En cuanto a la capacidad inhibitoria sobre COX-2, las muestras de manzanilla y limón presentaron los mayores porcentajes de inhibición, seguida de la infusión de boldo. En general, los resultados sugieren que las infusiones comerciales de boldo y hierbabuena muestran propiedades biológicas con beneficios potenciales a la salud.Actually there is an increase on infusion consumption due their beneficial properties, which are attributable to the presence of phenolic compounds. By this reason, the aim of this study was to assess phenolic content, antioxidant capacity and anti-inflammatory capacity of commercial infusions of peppermint (Mentha piperita L., lemon grass (Cymbopogon citratos, chamomile (Matricaria

  4. Seasonal carbon dioxide balance and respiration of a high-arctic fen ecosystem in NE-Greenland

    Turbulent fluxes of CO2 were continuously measured by eddy correlation for three months in 1997 over a gramineous fen in a high-arctic environment at Zackenberg (74o28'12''N, 20o34'23''W) in NE-Greenland. The measurements started on 1 June, when there was still a 1-2 m cover of dry snow, and ended 26 August at a time that corresponds to late autumn at this high-arctic site. During the 20-day period with snow cover, fluxes of CO2 to the atmosphere were small, typically 0.005 mg CO2 m-s-1 (0.41 g CO2 m-2d-1), whereas during the thawed period, the fluxes displayed a clear diurnal variation. During the snow-free period, before the onset of vegetation growth, fluxes of CO2 to the atmosphere were typically 0.1 mg CO2 m-2s-1 in the afternoon, and daily sums reached values up to almost 9 g CO2 m-2d-1. After 4 July, downward fluxes of CO2 increased, and on sunny days in the middle of the growing season, the net ecosystem exchange rates attained typical values of about -0.23 mg m-s-1 at midday and max values of daily sums of -12 g CO2 m-2d-1. Throughout the measured period the fen ecosystem acted as a net-sink of 130 g CO2 m-2. Modeling the ecosystem respiration during the season corresponded well with eddy correlation and chamber measurements. On the basis of the eddy correlation data and the predicted respiration effluxes, an estimate of the annual CO2 balance the calendar year 1997 was calculated to be a net-sink of 20 g CO2 m-2yr-1. (author)

  5. Carbon Dioxide and Methane Dynamics Trough Fen-Stream-Lake Continuum in North Boreal Zone, Finnish Lapland

    Juutinen, S.; Kuutti, V.; Valiranta, M.; Seppä, H.; Weckstrom, J.; Tuittila, E.

    2006-12-01

    This study aims to determine spatial and temporal variation in carbon dioxide (CO2) and methane (CH4) dynamics through a fen-lake continuum. Study was carried out in a catchment dominated by aapa mire over the period from spring 2005 to autumn 2006 in north boreal zone in Finnish Lapland. The study region characteristically has very high lake and mire density. To cover spatial variability we set measurement plots to different plant communities along moisture gradient in the fen and to different positions in the stream and lake. Six different mire communities, stream input to lake marginal mire, a lower stream site, lake in- and output sites, and three littoral and one pelagial site were measured. We measured CO2 and CH4 gas fluxes using closed chamber technique, and dissolved CO2 and CH4 concentrations using headspace equilibration technique weekly to biweekly over the open water season. In association of gas sampling peat and water temperatures, water levels in mire and lake, and stream flow rate were measured. Catchment boundaries and proportions of mire, lake and mineral soil area were determined using topographic maps, aerial photograph and field survey. Precipitation data is achieved from nearby weather station. We will present results of spatial and temporal pattern and seasonal budget of wetland atmosphere exchange of CO2 and CH4. Our preliminary results indicate that there is input of dissolved CO2 and CH4 from mire to the lake. In addition, our observations indicate that there is spatial variation in gas flux dynamics in aquatic environments in relation to the differences in stream flow rate and sediment quality. Seasonally varying hydrology causes changes in gas flux dynamics in all studied wetland surfaces. Information from this study improve the knowledge of carbon transport and balances in northern aapa mire region, where mires are commonly affected by through flow from watershed, and where number of small lakes is great.

  6. La fibra óptica y el fenómeno no lineal mezcla de cuarta onda

    Fabián Gómez López

    2015-12-01

    Full Text Available RESUMEN Para aprovechar de mejor manera el ancho de banda que tiene la fibra óptica, los sistemas de comunicaciones ópticos han tenido que aumentar la potencia de transmisión de las señales para poder transportar a grandes distancias la información. Debido a lo anterior, comienzan a producirse ciertos fenómenos ópticos no lineales como la mezcla de cuarta onda (Four Wave Mixing, FWM, que degradan la señal de información. En este documento se realiza un estado del arte de la fibra óptica y un estudio del fenómeno no lineal FWM, que se genera cuando dos o más señales ópticas se propagan en la fibra, lo cual conlleva a una mezcla de señales que puede generar nuevos componentes de interferencia de la señal óptica transmitida. ABSTRACT To make better use of the bandwidth that has the optical fiber, optical communications systems have had to increase the transmission power of signals to transport information over long distances. Because of this, certain nonlinear optical phenomena such as four wave mixing (Four Wave Mixing, FWM, which degrade the information signal begin to occur. Herein a state of the art of optical fiber and a study of the nonlinear FWM phenomenon, which is generated when two or more optical signals propagating in the fiber takes place, which leads to a mixture of signals that can generate new components interference of the transmitted optical signal.

  7. Sentimentos do adolescente relacionados ao fenômeno BULLYING: possibilidades para a Assistência de Enfermagem nesse contexto

    Agnes Schutz de Oliveira

    2006-04-01

    Full Text Available O bullying é um fenômeno devastador podendo vir a afetar a auto-estima e a saúde mental dos adolescentes. Geralmente ocorre quando o adolescente é mais suscetível ou vulnerável às agressões verbais ou morais que lhes causam angústia e dor, principalmente quando ocorrido em ambiente escolar traduzindo-se como uma forma de exclusão social. Pode desencadear alguns problemas de saúde tais como a anorexia, bulimia, depressão, ansiedade e até mesmo o suicídio. A enfermagem, pautada com princípios de prevenir agravos de diversos males, preocupa-se também com esta intercorrência traumática na adolescência. O objetivo deste estudo foi identificar sentimentos que possam estar relacionados com o bullying em adolescentes alunos de 5ª a 8ª séries. Tratou-se de uma pesquisa descritiva de abordagem qualitativa, realizada em uma escola de segmento religioso conveniada com o estado. A coleta de dados ocorreu auxiliada por entrevistas gravadas, posteriormente transcritas e submetidas à análise temática. Os resultados mostraram que os sentimentos relacionados ao fenômeno são múltiplos e variados, sendo categorizados como aspectos de caráter positivo, aspectos de caráter negativo e aspectos de caráter necessário.

  8. Changes of the CO2 and CH4 production potential of rewetted fens in the perspective of temporal vegetation shifts

    D. Zak

    2014-10-01

    Full Text Available Rewetting of long-term drained fens often results in the formation of eutrophic shallow lakes with an average water depth of less than 1 m. This is accompanied by a fast vegetation shift from cultivated grasses via submerged hydrophytes to helophytes. As a result of rapid plant dying and decomposition, these systems are highly-dynamic wetlands characterised by a high mobilisation of nutrients and elevated emissions of CO2 and CH4. However, the impact of specific plant species on these phenomena is not clear. Therefore we investigated the CO2 and CH4 production due to the subaqueous decomposition of shoot biomass of five selected plant species which represent different rewetting stages (Phalaris arundinacea, Ceratophyllum demersum, Typha latifolia, Phragmites australis, and Carex riparia during a 154 day mesocosm study. Beside continuous gas flux measurements, we performed bulk chemical analysis of plant tissue, including carbon, nitrogen, phosphorus, and plant polymer dynamics. Plant specific mass losses after 154 days ranged from 25 (P. australis to 64% (C. demersum. Substantial differences were found for the CH4 production with highest values from decomposing C. demersum (0.4 g CH4 kg−1 dry mass day that were about 70 times higher than CH4 production from C. riparia. Thus, we found a strong divergence between mass loss of the litter and methane production during decomposition. If C. demersum as a hydrophyte is included in the statistical analysis solely nutrient contents (nitrogen and phosphorus explain varying GHG production of the different plant species while lignin and polyphenols demonstrate no significant impact at all. Taking data of annual biomass production as important carbon source for methanogens into account, high CH4 emissions can be expected to last several decades as long as inundated and nutrient-rich conditions prevail. Different restoration measures like water level control, biomass extraction and top soil removal are

  9. Mapeamento do fenômeno de pulsações não-radiais no DHR

    Waelkens, A. H.; Janot Pacheco, E.

    2003-08-01

    Neste trabalho de IC, pretende-se estabelecer um mapa das características do fenômeno das pulsações não-radiais (PNR) no diagrama HR (DHR). Trata-se de oscilações que não mantém a homotecia radial. O fenômeno foi inicialmente descoberto no Sol nos anos 60 e hoje é detectado num grande número de objetos. Sua grande importância reside em que as pulsações descrevem a física da cavidade em que se propagam. As PNR são classificadas basicamente por suas frequências, amplitudes e certos números quânticos associados. Com o objetivo de descrever a variação desses parâmetros no DHR, procedeu-se a um extenso levantamento bibliográfico (artigos de revistas e outras fontes) cobrindo o tema. Compôs-se assim uma tabela, que será apresentada nesta comunicação, contendo os parâmetros físicos das estrelas (T, L, logg, M) e suas características de PNR, deduzidas a partir de observações fotométricas e/ou espectroscópicas. No momento, completamos os dados sobre as Anãs Brancas e Beta Cep. Apresentaremos no trabalho diagramas L-T com os últimos resultados obtidos, eventualmente com uma terceira dimensão que descreva características pulsacionais.

  10. Para Além do Estado e do Mercado: A Dádiva no Fenômeno dos Sem-Abrigo

    João Aldeia

    2014-03-01

    Full Text Available Las reflexiones sobre el fenómeno de los sin techo tienden a reproducir las ausencias que el paradigma del don identifica en el pensamiento sobre las sociedades modernas occidentales. Recurrentemente, se considera al Estado y al mercado como las únicas esferas de regulación social y se los interpreta como los espacios de donde derivan las causas estructurales y las posibles soluciones para el fenómeno. Ello no permite una comprensión completa del tema y tampoco una reflexión consistente sobre los modos de minimizar las injusticias de la vida en la calle. Pensar sobre el fenómeno por medio del paradigma del don es relevante porque permite identificar la habitual invisibilización de las relaciones interpersonales no oficiales que caracterizan la vida en la calle, posibilitando, a su vez, la revalorización de estas interacciones en el debate sobre el fenómeno de los sin techo.

  11. How a regional aquifer, a local aquifer and an oxbow lake impact on hydrological and biogeochemical processes in ariparian fen-meadow ecosystem

    Hoffmann, Carl Christian; Pedersen, Morten Lauge; Rasmussen, K. R.

    2009-01-01

    The groundwater flow pattern through a riparian fen-meadow was investigated by use of piezometer transects, soil survey, measurements of piezometric heads and measurements of hydraulic conductivity. Groundwater was sampled from piezometers and analysed for nitrate-N. Water balances and nitrate...

  12. The variation of testacean assemblages (Rhizopoda) along the complete base-richness gradient in fens: a case study from the Western Carpathians

    Opravilová, V.; Hájek, Michal

    2006-01-01

    Roč. 45, - (2006), s. 191-204. ISSN 0065-1583 R&D Projects: GA ČR GA206/02/0568 Institutional research plan: CEZ:AV0Z60050516 Keywords : Testacea * ecology * fens Subject RIV: EF - Botanics Impact factor: 1.162, year: 2006

  13. Desarrollo de técnicas de extracción y análisis de antocianinas y compuestos fenólicos en Jaboticaba (Myrciaria Cauliflora)

    Mera Morillo, Celia

    2015-01-01

    Desarrollo de técnicas de extracción mediante ultrasonidos y mediante fluidos presurizados para así, obtener las condiciones óptimas de extracción de las antocianinas mayoritarias y compuestos fenólicos totales presentes en la jaboticaba

  14. Compuestos fenólicos y flavonoides como marcadores bioquímicos de la respuesta a estrés abiótico en plantas tolerantes

    CALATAYUD VAELLO, PAU

    2011-01-01

    Calatayud Vaello, P. (2010). Compuestos fenólicos y flavonoides como marcadores bioquímicos de la respuesta a estrés abiótico en plantas tolerantes. http://hdl.handle.net/10251/9179. Archivo delegado

  15. Fenótipo cintura hipertrigliceridêmica: associação com alterações metabólicas em adolescentes

    Maria Ester P. da Conceição-Machado

    2013-02-01

    Full Text Available OBJETIVO: O presente estudo objetivou identificar a prevalência do fenótipo cintura hipertrigliceridêmica (CHT e avaliar sua associação com alterações metabólicas em adolescentes de baixa condição econômica. MÉTODO: Estudo transversal com amostra probabilística de 1.076 adolescentes entre 11 e 17 anos, de ambos os sexos, estudantes de escolas públicas. Os participantes foram submetidos à avaliação antropométrica (peso, altura e circunferência da cintura e à dosagem dos níveis de colesterol total, LDL-C, HDL-C, colesterol não HDL, triglicérides (TG e glicemia de jejum. Foram obtidas informações referentes às condições econômicas das famílias dos participantes.O fenótipo CHT foi definido pela presença simultânea da circunferência da cintura aumentada (> percentil 90 por idade e sexo e dos níveis séricos de triglicérides elevados (> 100 mg/dL. A análise de regressão logística foi utilizada para avaliação das associações de interesse. RESULTADOS: A prevalência do fenótipo CHT foi de 7,2% entre os adolescentes, sendo mais elevada na presença de obesidade (63,4%, do colesterol não HDL (16,6% e do LDL-C (13,7% altos. A análise bivariada indicou que, das variáveis metabólicas, apenas a glicemia não se associou ao fenótipo CHT. A análise multivariada, ajustada por sexo e idade, indicou que o fenótipo CHT se associou positivamente com o colesterol não HDL alto (odds ratio, 7,0; IC 95% 3,9-12,6 e com o HDL-C baixo (odds ratio, 2,7; IC 95%, 1,5-4,8. CONCLUSÕES: Este estudo mostrou que o fenótipo CHT se associou com um perfil lipídico aterogênico e sugere esse fenótipo como uma ferramenta de screening que pode ser utilizada para identificar adolescentes com alterações metabólicas.

  16. Avaliação da atividade antioxidante dos compostos fenólicos naturalmente presentes em subprodutos do pseudofruto de caju (Anacardium occidentale L. Evaluation of the Antioxidant Activity of Phenolic Compounds Naturally Contained in By-products of the Cashew Apple (Anacardium occidentale L.

    Priscila Regina Bolelli Broinizi

    2007-12-01

    Full Text Available O presente trabalho teve como proposta avaliar a capacidade antioxidante do bagaço e do extrato bruto concentrado (EBC do pedúnculo de caju, tendo em vista o seu aproveitamento. O potencial antioxidante dos extratos aquoso (EAq e alcoólico (EAlc e das frações de ácidos fenólicos livres (AFL e esterificadas (solúvel AFS e insolúvel AFI desses subprodutos do pedúnculo de caju clone CCP-76 foi avaliado em sistema beta-caroteno/ácido linoléico, pelo teste de varredura de radical livre [2,2 difenil-1-pricril-hidrazil (DPPH•] e de Rancimat. Além do mais, o conteúdo de fenólicos totais e o perfil de ácidos fenólicos foram determinados usando-se o reagente de Folin-Ciocateau e por cromatografia gasosa, respectivamente. O EAq e a fração AFL dos subprodutos apresentaram o maior conteúdo de fenólicos. As frações de ácidos fenólicos exibiram expressiva atividade antioxidante, superior aos extratos estudados nos sistemas beta-caroteno e DPPH. Entretanto no teste Rancimat, os extratos apresentaram maior proteção à oxidação em relação às frações e ao BHT. Nas frações foram identificados os ácidos gálico, ferúlico, caféico, protocatecuico, quínico, cinâmico, gentíssico, p-cumárico e salicílico, os quais lhes conferem o potencial antioxidante. Estes resultados caracterizaram in vitro o potencial antioxidante do bagaço e do EBC do pedúnculo de caju clone CCP-76.This study aimed to determine the antioxidant capacity of cashew apple pulp and raw concentrated extract. The antioxidant potential of aqueous (EAq and alcoholic (EAlc extracts and of free phenolic acids (FPA and esterified (soluble - SPA and insoluble - IPA fractions of the by-products of the cashew apple clone CCP-76 were evaluated in a beta-carotene-linoleate system by the free radical [2,2-diphenyl-1-picrylhydrazyl (DPPH•] scavenging assay and the Rancimat test. In addition, the total phenolic content and phenolic acid profile were determined using

  17. Composição fenólica de ligninas dioxano determinadas pela reação oxidativa com o nitrobenzeno

    Fukushima Romualdo Shigueo

    2003-01-01

    Full Text Available A correta quantificação da concentração de lignina em plantas forrageiras, pelo método espectrofotométrico, pressupõe a existência de um padrão de referência. Um padrão de referência deve ter composição fenólica semelhante à da lignina da parede celular. O objetivo deste trabalho foi verificar se ligninas extraídas com solução ácida de dioxano para serem utilizadas como padrão de referência, apresentariam variação na composição fenólica da mesma maneira que a lignina da parede celular. Amostras de parede celular de "bromegrass", milho e trevo-vermelho foram submetidas ao método para extração de ligninas com solução ácida de dioxano. A composição fenólica das ligninas foi analisada mediante oxidação alcalina pelo nitrobenzeno com posterior separação dos componentes monoméricos via HPLC. As ligninas extraídas confirmaram a existência de variação na composição fenólica da mesma maneira às ligninas intactas presentes na parede celular e de substancial presença de ácidos cinâmicos nas ligninas de gramíneas. No que diz respeito à composição fenólica, ligninas extraídas com solução ácida de dioxano podem ser consideradas potenciais padrões de referência paras as análises espectrofotométricas.

  18. Produção de mudas de cultivares de alface utilizando duas espumas fenólicas em Altamira, Pará

    Alzirio Lino Couto

    2015-06-01

    Full Text Available O sucesso de qualquer produção comercial de hortaliças inicia-se com a produção de mudas. A espuma fenólica tem se mostrado um interessante e prático substrato para este processo. A utilização deste produto depende de uma lavagem precedente para reduzir a acidez. Porém, já é possível encontrar à venda espumas fenólicas com pH próximo. Por isso o objetivo deste trabalho foi avaliar a produção de mudas de cultivares de alface utilizando duas espumas fenólicas em Altamira, Pará. O delineamento constou de um esquema fatorial 2 (substratos x 6 (cultivares. Os dois substratos foram as espumas fenólicas Green Up®, com pH 6.0 (± 0.5., e a outra com pH 2.6 (± 0.5. As cultivares avaliadas foram: Alcione, Amanda, Lucy Brown, Caipira, Multiblond 3 e Solaris. Foi avaliada porcentagem de germinação, índice de velocidade de emergência, altura da planta e número de folhas. Houve diferença significativa para altura da planta em função dos substratos testados. A porcentagem de germinação mais elevada foi obtida com a espuma fenólica sem tratamento. A cultivar Caipira foi a que teve o menor desempenho na germinação. Para todas as variáveis analisadas, a cultivar Lucy Brown apresentou os melhores resultados em ambos os substratos.

  19. The delta 6 desaturase knock out mouse reveals that immunomodulatory effects of essential n-6 and n-3 polyunsaturated fatty acids are both independent of and dependent upon conversion.

    Monk, Jennifer M; Liddle, Danyelle M; Cohen, Daniel J A; Tsang, Denis H; Hillyer, Lyn M; Abdelmagid, Salma A; Nakamura, Manabu T; Power, Krista A; Ma, David W L; Robinson, Lindsay E

    2016-06-01

    Typically fatty acids (FA) exert differential immunomodulatory effects with n-3 [α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] and n-6 [linoleic acid (LA) and arachidonic acid (AA)] exerting anti- and pro-inflammatory effects, respectively. This over-simplified interpretation is confounded by a failure to account for conversion of the parent FA (LA and ALA) to longer-chain bioactive products (AA and EPA/DHA, respectively), thereby precluding discernment of the immunomodulatory potential of specific FA. Therefore, we utilized the Δ6-desaturase model, wherein knockout mice (D6KO) lack the Fads2 gene encoding for the rate-limiting enzyme that initiates FA metabolism, thereby providing a model to determine specific FA immunomodulatory effects. Wild-type (WT) and D6KO mice were fed one of four isocaloric diets differing in FA source (9weeks): corn oil (LA-enriched), arachidonic acid single cell oil (AA-enriched), flaxseed oil (ALA-enriched) or menhaden fish oil (EPA/DHA-enriched). Splenic mononuclear cell cytokine production in response to lipopolysaccharide (LPS), T-cell receptor (TCR) and anti-CD40 stimulation was determined. Following LPS stimulation, AA was more bioactive compared to LA, by increasing inflammatory cytokine production of IL-6 (1.2-fold) and TNFα (1.3-fold). Further, LPS-stimulated IFNγ production in LA-fed D6KO mice was reduced 5-fold compared to LA-fed WT mice, indicating that conversion of LA to AA was necessary for cytokine production. Conversely, ALA exerted an independent immunomodulatory effect from EPA/DHA and all n-3 FA increased LPS-stimulated IL-10 production versus LA and AA. These data definitively identify specific immunomodulatory effects of individual FA and challenge the simplified view of the immunomodulatory effects of n-3 and n-6 FA. PMID:27142734

  20. Kinetics and Mechanism of Oxidation of Phenyl Acetic Acid and Dl-Mandelic Acid by Permanganate in Acid Medium

    B. Syama Sundar; P.S.Radhakrishna murti

    2014-01-01

    Kinetics of oxidation of phenyl acetic acid and DL- Mandelic acid by potassium permanganate in aqueous acetic acid and perchloric acid mixture reveals that the kinetic orders are first order in oxidant, first order in H+ and zero order in substrate for phenyl acetic acid. DL-Mandelic acid exhibits first order in oxidant and zero order in substrate. The results are rationalised by a mechanism involving intermediate formation of mandelic acid in case of Phenyl acetic acid and ester formation wi...

  1. Effects of N and P fertilisation on greenhouse gas (GHG) production in floodplain fen peat: A microcosm fertilisation experiment.

    Stanley, Kieran; Heppell, Catherine; Belyea, Lisa; Baird, Andrew

    2016-04-01

    Biogeochemical and hydrological cycles are being significantly perturbed by anthropic activities altering atmospheric mole fractions of greenhouse gases (GHG) and increasing global temperatures. With the intensification of the hydrological cycle, lowland areas, such as floodplain fens, may be inundated more frequently. Rivers in agricultural catchments have the potential to pollute floodplain fens with significant amounts of nitrogen (N) and phosphorus (P); however, the effects of short-term (control, glucose (G), N+G, P+G, and N+P+G), fully-factorial microcosm experiment was designed and undertaken in Spring 2013 with peat from two floodplain fens under conservation management with similar vegetation (from Norfolk, United Kingdom). One site receives a higher nutrient load than the other and has a historical legacy of higher N and P contents within the peat. Results from the experiment showed no significant difference in CO2 production between the control and fertilised treatments from 0 to 96 hours, but a significant difference between treatments (ANCOVA, between factors: treatment and site; covariate: time; F4,419 = 11.844, p < 0.001) and site (F1,149 = 5.721, p = 0.017) from 96 hours to in the end of the experiment due to fermentation. N2O production only occurred in samples fertilised with N (N+G and N+P+G) due to denitrification. Rates of N2O production were significantly greater in samples from the lower-nutrient site in comparison to the nutrient-rich site (t12= 6.539, p < 0.001 and t12= 7.273, p < 0.001 for N+G and N+P+G fertilised samples, respectively). Fertilisation with N and P had different effects on CH4 production. Samples fertilised with P+G had the highest CH4 production (ANCOVA, between factors: treatment and site; covariate: time; F4,120= 15.026, p < 0.001). Samples fertilised with N (N+G and N+P+G) showed CH4 inhibition in comparison to G and P+G additions. CH4 production was significantly greater from the nutrient-rich peat than from the lower

  2. La dictadura militar en Grecia (1967- 1974. ¿Cómo enfocar el fenómeno autoritario?

    Georges D. CONTOGEORGIS

    2010-02-01

    Full Text Available RESUMEN: La Dictadura de los Coroneles es abordada como un fenómeno inherente al déficit democrático, no tanto de la sociedad griega, sino del sistema internacional. El hecho de que la Dictadura Griega se atribuya a valores geoestratégicos y al déficit democrático (p.e. la prohibición del acceso al poder de los partidos políticos no liberales de los líderes de la Guerra Fría está también en sintonía con la diferencia fundamental que lo distingue de las dictaduras de la Península Ibérica. Estas últimas están relacionadas con un mismo fenómeno anterior de la Europa anterior a la Segunda Guerra Mundial y como tales están clasificadas como una parte del proceso de transición que tuvo lugar en el Viejo Continente. Por el contrario, el fenómeno autoritario en el sistema político griego constituye un paréntesis porque la sociedad griega no experimentó la transición del feudalismo a la modernidad y su sistema político fue desde el comienzo (desde 1821 el primero entre los estados-nación con una base representativa asentada sobre el sufragio universal. Todo ello demuestra que las distinciones entre Norte y Sur, relativas a la democracia, están ideológicamente condicionadas y no derivan de conclusiones extraídas del desarrollo político de las sociedades. Palabras clave: Totalitarismo, Dictadura, Déficit democrático, Estado representativo, Guerra Fría, Protesta, Consenso político. ABSTRACT: The Dictatorship of the Colonels is approached as a phenomenon, which is inherent in the democratic deficit, not of Greek society, but of the international system. The fact that the Greek Dictatorship is attributed to geostrategic reasons and to the democratic deficit (e.g. the prohibition of access to power of non-liberal political parties of the leaders of the Cold War is also in line with the fundamental difference, which distinguishes it from dictatorships of the Iberian Peninsula. The latter are related to the same phenomena of

  3. Uranium entrapment in wetlands: A case study at the Boston Peak fen, Colorado, U.S.A

    The Boston Peak fen, a 5-hectare, uranium-enriched wetland located northwest of Rocky Mountain National Park in northern Colorado, has been the subject of intensive study by U.S. Geological Survey scientists through surface mapping, drilling, and sampling of an extensive network of 59 auger and core holes. Uranium concentrations increased dramatically in the organic-rich gyttja (50-150 ppm) compared to the lower lakebeds (4-70 ppm). The uranium in the gyttja is stratabound, and variations in uranium content between sediment layers could be caused by differences in supply of dissolved uranium to the lake and differences in sediment redox conditions. Uranium concentrations in the gyttja drop before the transition to peat, except in lake sediment near spring or seep sources, despite the constant or increasing organic matter content of the gyttja. Dissolved uranium delivered by spring water was now locally fixed by peat adjacent to the spring pools, resulting in uranium concentrations of as much as 4,000 ppm (dry weight) whereas peat distant from spring pools may have only a few ppm of uranium. Water chemistry and uranium in peat are discussed. Studies of this wetland confirm the well-documented observation that wetlands serve as natural filters for uranium and many other potentially hazardous trace elements that may otherwise enter downstream surface waters. Inadvertent or deliberate destruction of metalbearing wetlands may diminish water quality and remove the potential for continued filtering activity. The processes affecting uranium transport, sorption, and ultimate fixation in the peat may have relevance for understanding uranium-organic associations in ore deposits in the major sandstone uranium districts of the San Juan Basin and elsewhere. Stratabound uranium in the gyttja may serve as an analogue of much older uranium- and organic-matter-rich systems such as the massive low-grade lacustrine uranium deposits of late Tertiary age in some western Arizona basins

  4. The role of plant functional groups in methane dynamics in a boreal fen under pristine and water level drawdown conditions

    Riutta, T.; Tuittila, E.-S.; Laine, J.

    2012-04-01

    Vegetation and hydrology are important controlling factors in peatland methane dynamics. Vegetation structures (i.e. species composition, physiognomy, density) and productivity are strongly interlinked with moisture conditions (water table level variation), and the methane flux is a result of the vegetation-water table interaction, rather than a direct effect of water table or vegetation. Therefore, observational studies in pristine peatlands have a limited ability to separate the effects of these factors. This study aimed to experimentally quantify the role of the fen ecosystem components - sedges, dwarf shrubs, Sphagnum mosses, and the underlying peat - in methane fluxes in control and experimental water table drawdown conditions and to separate the plant-mediated effects from the effect of altered water table level on methane fluxes. We carried out the experiment in a boreal nutrient-poor fen using two treatments: a vegetation component removal treatment with four levels and a water level treatment with two levels (control and a 15 cm water level draw down). We measured methane fluxes during four growing seasons using a static chamber technique. The first year was a calibration season preceding the water level drawdown treatment. Based on the vegetation removal treatments, plant-mediated fluxes comprised 75% of the total cumulative growing season methane flux (7.8 ± 0.83 g CH4 m-2 from June to September) in the control water level conditions. Sedge and Sphagnum moss mediated fluxes accounted for 48% and 27% of the total flux, respectively. The presence of dwarf shrubs, on the other hand, had a slightly attenuating effect on the fluxes. In water level drawdown conditions, fluxes were significantly lowered (cumulative growing season flux 0.12 ± 0.10 g CH4 m-2) and the presence / absence of the plant groups had hardly any effect on the fluxes. There was a tight, positive relationship between net ecosystem production and methane flux in the control conditions but

  5. Impact of drainage on wettability of fen peat-moorsh soils

    Szajdak, L.; Szatyłowicz, J.; Brandyk, T.

    2009-04-01

    High water retention in peat is attributed to structural voids (macro-pores) due to the partial degradation of the structure of peat-forming plants, and molecular absorption sites (micro-pores) associated with the formation of humic substances. Water retention by the heterogeneously-structured system in peat organic matter depends on the chemical structure of solid surfaces. These naturally wet solids, if dried sufficiently, lose the ability to rewet quickly when immersed in water. The ability of peat surfaces to attract and hold water is attributed to hydrophilic functional groups which characterize the organic substances of peat. The investigations of chemical and physical properties were performed for three different peat-moorsh soils located in the Biebrza River Valley in Poland. All examined soils were used as meadow. Soil samples were taken from two depths: 5-10 cm (moorsh) and 50-80 cm (peat). Total organic carbon (TOC), dissolved organic carbon (DOC) and humic acids (HA) extracted from these samples were analysed. Also basic physical properties such as ash content and bulk density were measured. Wetting behavior of soils was quantified using water drop penetration time test (WDPT) and measured values of the soil-water contact angle using sessile drop method. The measurements were conducted on air-dry soil samples which volumetric moisture content was not exceeding 7%. The significant differences in the concentrations of TOC, DOC and properties of HA between two investigated depth of among peat and moorsh samples were observed. The measured concentrations of total organic carbon in the considered soils ranged from 37.2 to 45.6%. Generally, the decrease of total organic carbon concentration with depth of profiles was observed. The contents of dissolved organic carbon in the soils ranged from 5.3 to 19.4%. The quantities of dissolved organic carbon decreased simultaneously with E4/E6 values and with the depth of the soil profiles. For the investigated peat

  6. Işık ünitesinde similasyon yönteminin kullanılmasının öğrencilerin Fen başarısına ve Fen tutumlarına etkisi

    Küçük, Taner

    2014-01-01

    Bu tez çalışmasında, bilgisayar ortamında gerçek durumların birebir oluşturulmasını sağlayan simülasyon yönteminin öğrenci başarısına ve tutumuna etkisi incelenmiştir. Çalışmanın evren ve örneklemi Çanakkale ili Kepez ilçesi Mehmet Akif Ersoy Ortaokulu 7.sınıfta öğrenim gören 98 öğrencidir. Deney grubu olarak 7/A ve 7/C sınıflarından toplam 52 öğrenci, kontrol grubu olaraksa 7/B ve 7/D sınıflarından toplam 46 öğrenci seçilmiştir. Öntest sontest kontrol gruplu desen kullanılan araştırmada, fen...

  7. Antioxidant activity and phenolic content of agricultural by-products from wine production/ Atividade antioxidante e conteúdo fenólico do resíduo agroindustrial da produção de vinho

    Eugênia Marta Kuskoski

    2008-08-01

    Full Text Available The present work aimed to investigate the antioxidant properties of byproducts derived from wine production. The varieties of PINOT GRIS and COUDERC 13 grapes, collected in Videira-SC, were analyzed as natural sources of polyphenols and other prophylactic agents (antioxidants for application in food and phytochemical industries. The biomass used for extracts was ground and dried in different temperatures (45oC, 60oC e 80oC, using acetone 80% as solvent. The phenolic compounds were quantitatively evaluated by the Folin-Ciocalteu method and the results expressed in mg/100g of Gallic acid. For the flavonoids analysis, it was applied DMACA (p- Dimethylaminocinnamaldehye method and the results were expressed in equivalent mg of catechin/100g sample. The antioxidant activity was evaluated by spectrophotometric method through the discoloration of ABTS•+ radical (2,2'-azino-bis[3- ethylbenzthiazoline-6-sulfonic acid] with potassium persulphate and by DPPH method, which is based on the reduction of DPPH• radical absorbance by antioxidant substances; the results were expressed in TEAC (antioxidant activity equivalent to Trolox and VCEAC (antioxidant activity equivalent to vitamin C. It was observed a better antioxidant activity on extracts obtained from PINOT GRIS grapes, in which the 45 oC dried extracts presented a higher number of phenolic compounds and flavonoids, as well as a better antioxidant activity in both varieties. These information become useful for phenolic compounds identifying and for a possible using of these extracts as a secure additive in food industry.Este trabalho propõe uma investigação do potencial antioxidante do resíduo no processamento de uvas das variedades COUDERC 13 e PINOT GRIS, ambas coletadas em Videira-SC, como fonte natural de polifenóis e outros agentes profiláticos (antioxidantes para aplicação nas indústrias alimentícia e de fitoterápicos. A biomassa utilizada para obtenção dos extratos foi triturada

  8. Epitaxial Ni3FeN thin films: A candidate for spintronic devices and magnetic sensors

    A new type of epitaxial ferromagnetic nitride (Ni3 Fe N = permalloy nitride = “PyN”) compound films were grown on Al2O3(1120) substrates using reactive triode magnetron sputtering. The results of electron back-scattering diffraction and x-ray diffraction techniques indicate a high quality epitaxial crystalline structure with growth normal of (100). Magnetization measurements of epitaxial PyN films revealed several unique results. (1) A textbook square hysteresis loop that suggest existence of single magnetic domain in these films. (2) A coercive field is tunable from a few mOe up to a few Oe by changing the film thickness. (3) A magnetization that switches (rotate) over a very small field range of δHC ≤ 0.05 Oe, independent of the film thickness. This small δH indicates a very large resistive sensitivity (δR/δH) of the epitaxial PyN. (4) The epitaxial PyN thermal cycling through several cycles between “2 and 800 K” (-271 °C to +527 °C) shows much less degradation only about 2-5% compared to 40% degradation of a simple Py film. Four-probe transport measurements give an anisotropic magnetoresistance of ≈6%, sufficiently higher than other known ferromagnetic materials. These interesting properties are ideal for a variety of spintronic devices and magnetic sensors.

  9. The c/a Ratio in Quenched Fe-C and Fe-N steels - a Heuristic Story

    Sherby, O; Wadsworth, J; Lesuer, D; Syn, C

    2006-01-31

    The body-centered tetragonal (BCT) structure in quenched Fe-C steels is usually illustrated to show a linear change in the c and a axes with an increase in carbon content from 0 to 1.4%C. The work of Campbell and Fink, however, shows that this continuous linear relationship is not correct. Rather, it was shown that the body-centered-cubic (BCC) structure is the stable structure from 0 to 0.6 wt%C with the c/a ratio equal to unity. An abrupt change in the c/a ratio to 1.02 occurs at 0.6 wt%C. The BCT structure forms, and the c/a ratio increases with further increase in carbon content. An identical observation is noted in quenched Fe-N steels. This discontinuity is explained by a change in the transformation process. It is proposed that a two-step transformation process occurs in the low carbon region, with the FCC first transforming to HCP and then from HCP to BCC. In the high carbon region, the FCC structure transforms to the BCT structure. The results are explained with the Engel-Brewer theory of valence and crystal structure of the elements. An understanding of the strength of quenched iron-carbon steels plays a key role in the proposed explanation of the c/a anomaly based on interstitial solutes and precipitates.

  10. Hacia una caracterización psico-social del fenómeno de callejerización

    Elvia Taracena Ruiz

    2010-01-01

    Full Text Available En este artículo realizo una reflexión crítica de mis investigaciones durante 20 años de trabajo con jóvenes y niños en situación de calle. Pongo el énfasis en la definición de la problemática en la articulación de tres registros: macro, medio y micro. Describo el marco teórico-metodológico en donde planteo la necesidad de construir un marco multireferencial y transdisciplinario.Cuestiono la relación del sujeto investigador con el problema estudiado y señalo la importancia del análisis de su implicación. Describo las condiciones sociales que propician la salida a la calle de los jóvenes y las jóvenes, y analizo las consecuencias en el sujeto joven en proceso de callejerización del desarrollo del mercado humanitario. Pongo el énfasis en la construcción de un marco teórico- metodológico buscando respetar tanto la singularidad como complejidad del fenómeno a través de una aproximación cualitativa.

  11. Water level, vegetation composition and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    Minke, M.; Augustin, J.; Burlo, A.; Yarmashuk, T.; Chuvashova, H.; Thiele, A.; Freibauer, A.; Tikhonov, V.; Hoffmann, M.

    2015-10-01

    Rewetting of temperate continental cutover peatlands generally implies the creation of flooded areas, which are - dependent on water depth - colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis. Reeds of Typha and Phragmites are reported to be large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. This paper describes the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse emissions were measured with manual chambers in weekly to few - weekly intervals over a two years period and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions were generally associated with net ecosystem CO2 uptake. Small sedges were minor methane emitters and net CO2 sinks, while Phragmites australis sites released large amounts of methane and sequestered very much CO2. Variability of both fluxes increased with site productivity. Floating mats composed of Carex tussocks and Typha latifolia were a source for both methane and CO2. We conclude that shallow, stable flooding is a better measure to arrive at low GHG emissions than deep flooding, and that the risk of high GHG emissions consequent on rewetting is larger for eutrophic than for mesotrophic peatlands.

  12. Response of plant community structure and primary productivity to experimental drought and flooding in an Alaskan fen

    Churchill, A.C.; Turetsky, Merritt R.; McGuire, Anthony; Hollingsworth, Teresa N.

    2014-01-01

    Northern peatlands represent a long-term net sink for atmospheric CO2, but these ecosystems can shift from net carbon (C) sinks to sources based on changing climate and environmental conditions. In particular, changes in water availability associated with climate control peatland vegetation and carbon uptake processes. We examined the influence of changing hydrology on plant species abundance and ecosystem primary production in an Alaskan fen by manipulating the water table in field treatments to mimic either sustained flooding (raised water table) or drought (lowered water table) conditions for 6 years. We found that water table treatments altered plant species abundance by increasing sedge and grass cover in the raised water table treatment and reducing moss cover while increasing vascular green area in the lowered water table treatment. Gross primary productivity was lower in the lowered treatment than in the other plots, although there were no differences in total biomass or vascular net primary productivity among the treatments. Overall, our results indicate that vegetation abundance was more sensitive to variation in water table than total biomass and vascular biomass accrual. Finally, in our experimental peatland, drought had stronger consequences for change in vegetation abundance and ecosystem function than sustained flooding.

  13. Methane dynamics in an alpine fen: a field-based study on methanogenic and methanotrophic microbial communities.

    Franchini, Alessandro G; Henneberger, Ruth; Aeppli, Meret; Zeyer, Josef

    2015-03-01

    Wetlands are important sources of the greenhouse gas methane (CH4). We provide an in situ study of CH4 dynamics in the permanently submerged soil of a Swiss alpine fen. Physico-chemical pore water analyses were combined with structural and microbiological analyses of soil cores at high vertical resolution down to 50 cm depth. Methanotrophs and methanogens were active throughout the depth profile, and highest abundance of active methanotrophs and methanogens [6.1 × 10(5) and 1.1 × 10(7) pmoA and mcrA transcripts (g soil)(-1), respectively] was detected in the uppermost 2 cm of the soil. Active methanotrophic communities in the near-surface zone, dominated by viable mosses, varied from the communities in the deeper zones, but further changes with depth were not pronounced. Apart from a distinct active methanogenic community in the uppermost sample, a decrease of acetoclastic Methanosaetaceae with depth was observed in concomitance with decreasing root surface area. Overall, root surface area correlated with mcrA transcript abundance and CH4 pore water concentrations, which peaked (137.1 μM) at 10 to 15 cm depth. Our results suggest that stimulation of methanogenesis by root exudates of vascular plants had a stronger influence on CH4 dynamics than stimulation of CH4 oxidation by O2 input. PMID:25789997

  14. Acciones gubernamentales frente a los desastres provocados por fenómenos hidrometeorológicos en México

    Gabriel Angelotti Pasteur

    2015-02-01

    Full Text Available Las acciones realizadas tras los desastres constituyen una oportunidad para el cambio social, en específico, para construir sociedades resilientes. Sin embargo, cuando en los procesos de reconstrucción se persiguen intereses exógenos (económicos, sociales o políticos y, preferentemente, ajenos a las necesidades de la sociedad afectada, se incrementan las condiciones de riesgo y la vulnerabilidad ante futuras amenazas. En el presente trabajo se analiza lo ocurrido en Yucatán (México cuando, tras el paso del huracán Isidoro (2002, se implementó un programa de reconstrucción con el fin de suplir aquellas viviendas que habían sido dañadas y destruidas por ese fenómeno hidrometeorológico. Mediante el mismo se esperaba dotar a las familias damnificadas de una vivienda digna, resistente, moderna y, de este modo, contribuir a forjar una sociedad más segura. Sin embargo, los resultados alcanzados ponen en duda esta meta del gobierno.

  15. El análisis discursivo de fenómenos de violencia en un corpus de prensa digital

    Carmen Ávila Martín

    2014-08-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE El análisis del discurso mediático dispone en la actualidad de herramientas que proporcionan análisis empíricos cuantitativamente más documentados que los análisis tradicionales. El análisis léxico de las coocurrencias discursivas aporta datos de interés para interpretar cómo se construyen los discursos. Nuestro interés se sitúa en el empleo de la Lingüística de Corpus como instrumento para el Análisis del Discurso, pues ambas disciplinas presentan en la actualidad metodología adecuada para la interpretación de discursos como auxiliares en el análisis e interpretación de determinados fenómenos significativos. Para ello utilizaremos corpus específicos que nos aportan datos sobre la utilización discursiva de las unidades analizadas. Nos detendremos en determinadas manifestaciones de violencia en textos periodísticos que tienen denominaciones específicas en inglés y en español, no siempre coincidentes.

  16. Fen (n=1–6) clusters chemisorbed on vacancy defects in graphene: Stability, spin-dipole moment, and magnetic anisotropy

    Haldar, Soumyajyoti

    2014-05-09

    In this work, we have studied the chemical and magnetic interactions of Fen (n=1–6) clusters with vacancy defects (monovacancy to correlated vacancies with six missing C atoms) in a graphene sheet by ab initio density functional calculations combined with Hubbard U corrections for correlated Fe-d electrons. It is found that the vacancy formation energies are lowered in the presence of Fe, indicating an easier destruction of the graphene sheet. Due to strong chemical interactions between Fe clusters and vacancies, a complex distribution of magnetic moments appear on the distorted Fe clusters which results in reduced averaged magnetic moments compared to the free clusters. In addition to that, we have calculated spin-dipole moments and magnetic anisotropy energies. The calculated spin-dipole moments arising from anisotropic spin density distributions vary between positive and negative values, yielding increased or decreased effective moments. Depending on the cluster geometry, the easy axis of magnetization of the Fe clusters shows in-plane or out-of-plane behavior.

  17. Fenómenos fisiopatológicos sistémicos asociados al bruxismo de sueño

    V. Iturriaga

    2014-12-01

    Full Text Available El bruxismo de sueño (BS se define como un trastorno del movimiento estereotipado que se presenta durante el sueño, caracterizado por rechinamiento y/o apretamiento dentario. Se encuentra dentro de la clasificación internacional de desórdenes de sueño como un trastorno del movimiento asociado a una exagerada actividad muscular masticatoria rítmica. Se reporta una incidencia del 15% al 22% en la población general. Antiguamente se creía que la etiología del BS estaba relacionada con alteraciones oclusales; sin embargo actualmente se piensa que la causa principal está más bien relacionada con alteraciones de sueño, enfermedades del sistema nervioso central, drogas, dolor crónico, alteraciones emocionales, entre otros factores que participarían en su origen. Se ha identificado la presencia de diversos fenómenos fisiopatológicos sistémicos que acontecen durante un episodio de BS, entre los cuales encontramos los microdespertares corticales, alteraciones en el ritmo cardíaco, el tono simpático, la presión arterial, entre otros, sobre los cuales trata esta revisión.

  18. Annual balances of CH4 and N2O from a managed fen meadow using eddy covariance flux measurements

    Annual terrestrial balances of methane (CH4) and nitrous oxide (N2O) are presented for a managed fen meadow in the Netherlands for 2006, 2007 and 2008, using eddy covariance (EC) flux measurements. Annual emissions derived from different methods are compared. The most accurate annual CH4 flux is achieved by gap filling EC fluxes with an empirical multivariate regression model, with soil temperature and mean wind velocity as driving variables. This model explains about 60% of the variability in observed daily CH4 fluxes. Annual N2O emissions can be separated into background emissions and event emissions due to fertilization. The background emission is estimated using a multivariate regression model also based on EC flux data, with soil temperature and mean wind velocity as driving variables. The event emissions are estimated using emission factors. The minimum direct emission factor is derived for six fertilization events by subtracting the background emission, and the IPCC default emission factor of 1% is used for the other events. In addition, the maximum direct emission factors are determined for the six events without subtracting the background emission. The average direct emission factor ranges from 1.2 to 2.8%, which is larger than the IPCC default value. Finally, the total terrestrial greenhouse gas balance is estimated at 16 Mg ha-1 year-1 in CO2-equivalents with contributions of 30, 25 and 45% by CO2, CH4 and N2O, respectively.

  19. On-Orbit Geometric Calibration Approach for High-Resolution Geostationary Optical Satellite GaoFen-4

    Wang, Mi; Cheng, Yufeng; Long, Xiaoxiang; Yang, Bo

    2016-06-01

    The GaoFen-4 (GF-4) remote sensing satellite is China's first civilian high-resolution geostationary optical satellite, which has been launched at the end of December 2015. To guarantee the geometric quality of imagery, this paper presents an on-orbit geometric calibration method for the area-array camera of GF-4. Firstly, we introduce the imaging features of area-array camera of GF-4 and construct a rigorous imaging model based on the analysis of the major error sources from three aspects: attitude measurement error, orbit measurement error and camera distortion. Secondly, we construct an on-orbit geometric calibration model by selecting and optimizing parameters of the rigorous geometric imaging model. On this basis, the calibration parameters are divided into two groups: external and internal calibration parameters. The external parameters are installation angles between the area-array camera and the star tracker, and we propose a two-dimensional direction angle model as internal parameters to describe the distortion of the areaarray camera. Thirdly, we propose a stepwise parameters estimation method that external parameters are estimated firstly, then internal parameters are estimated based on the generalized camera frame determined by external parameters. Experiments based on the real data of GF-4 shows that after on-orbit geometric calibration, the geometric accuracy of the images without ground control points is significantly improved.

  20. Response of vegetation structure and function to experimental drought and flooding in an Alaskan fen

    Churchill, A. C.; Hollingworth, T. N.; McGuire, A. D.; Turetsky, M. R.

    2010-12-01

    GPP in the flooded plot. Both the control and flooded plots showed little change in GPP in response to natural flooding (2008) or drought (2009). However, low fluxes in these plots in 2010 may indicate a one-year lag in vegetation response to drought. In our drought treatment, natural flooding stimulated GPP in 2008. Our data reveal that directional changes in water table position created by our manipulations have a significant effect on both vegetation structure and function, and govern how vegetation responds to inter-annual variation. Understanding vegetation responses to environmental change over seasonal, annual, and decadal time scales will improve our understanding of peatland complexity and potential adaptations to future climate change.

  1. FEN LABORATUARLARININ İŞLEVSELLİĞİNİN İLKÖĞRETİM OKULLARINDA DEĞERLENDİRİLMESİ

    YILAYAZ, Ömer; Turan, Mehmet; BAHŞİ, Muammer

    2009-01-01

    Bu araştırmada, ilköğretim okullarındaki fen laboratuarlarının işlevselliğine ilişkin öğrenci görüşlerinin belirlemesi amaçlanmıştır. Bu amaçla 19 maddelik bir anket formu hazırlanmıştır. Çalışma, Fırat Üniversitesi Eğitim Fakültesi Fen ve Teknoloji öğretmenliği bölümünde öğrenim gören 76 öğrenciye (4. sınıf) uygulanmıştır. Anket sonucunda elde edilen veriler, SPSS paket istatistik programında değerlendirilmiştir.

  2. Catalytic reaction on FeN4/C site of nitrogen functionalized carbon nanotubes as cathode catalyst for hydrogen fuel cells

    Gao, Feng [Southern Univ., Baton Rouge, LA (United States); A& M College, Baton Rouge, LA (United States); Zhao, Guang-Lin [Southern Univ., Baton Rouge, LA (United States); A& M College, Baton Rouge, LA (United States); Wang, Zhou [Southern Univ., Baton Rouge, LA (United States); A& M College, Baton Rouge, LA (United States); Bagayoko, Diola [Southern Univ., Baton Rouge, LA (United States); Liu, Di-Jia [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-21

    First, we utilized first-principles spin-polarized density functional theory (DFT) calculations to study the electrocatalytic reaction steps on FeN4/C site of carbon nanotubes. O2 molecule can be adsorbed and partially reduced on FeN4/C site without any activation energy barrier. The partially reduced O2 further reacts with H+ and e- through a direct pathway (DPW) and form two water molecules without any activation energy barrier. Through an indirect pathway (IDPW), there is an activation energy barrier of ~ 0.15 eV for the formation of the first H2O molecule. Finally, the formation of the second H2O molecule through IDPW does not have any activation energy barrier.

  3. La definición jurídica del fenómeno metropolitano en el ámbito subnacional mexicano

    Alberto Arellano Ríos

    2014-10-01

    Full Text Available En este texto se analiza la definición jurídica del fenómeno metropolitano en seis Estados de la república mexicana. Se estudian seis legislaciones estatales creadas expresamente para atender y darle forma jurídica a un problema que se ha acentuado con mayor fuerza en México, el cual desde el punto de vista de las instancias gubernamentales tiene mayor relevancia en los últimos veinte años. De este modo, el documento esboza el fenómeno metropolitano como contexto social. Luego traza los mecanismos constitucionales contemplados para gestionar y gobernar las zonas metropolitanos para, finalmente, exponer los casos estatales que ante la ausencia de un marco legal nacional, y desde la lógica del sistema federal, intentan sentar bases jurídicas para resolver este problema.

  4. estudo exploratório sobre o fenómeno no Estabelecimento Prisional de Paços de Ferreira

    Ferreira, Ana Cristina Oliveira

    2011-01-01

    O presente estudo aborda o fenómeno das saídas precárias (SP) enquanto licenças de saída do estabelecimento prisional (EP) que, à semelhança das visitas, correspondência, contactos telefónicos e outros meios de comunicação, constituem uma das formas que os reclusos têm de contactar com o exterior (Lei n.º 115/2009, de 12 de Outubro). Dada a escassez de estudo nesta área, considerou-se importante dar um contributo para a compreensão deste fenómeno, tendo-se estabelecido como principais obje...

  5. La Interacción Mutua entre Fuentes y las Aparentes Anomalías en el Fenómeno de Interferencia

    Reinaldo Welti

    2002-01-01

    Full Text Available En la mayoría de los textos de física del nivel básico universitario al tratar el fenómeno de interferencia suponen que las fuentes irradian de la misma forma cualquiera sea la distancia entre ellas. En algunas situaciones esta suposición puede llevar a aparentes anomalías en la conservación de la energía. En este trabajo se muestra que estas anomalías se resuelven solamente si el fenómeno de interferencia se presenta en un contexto que tenga en cuenta las interacciones entre las fuentes y el generador que suministra energía a las mismas.

  6. How a Sphagnum fuscum-dominated bog changed into a calcareous fen: the unique Holocene history of a Slovak spring-fed mire

    Hajkova, Petra; Grootjans, A. B.; Lamentowicz, Mariusz; Rybnickova, Eliska; Madaras, Mikulas; Opravilova, Vera; Michaelis, Dierk; Hajek, Michal; Joosten, Hans; Wolejko, Leslaw; Rybníčková, Eliška; Madaras, Mikuláš; Opravilová, Věra; Wołejko, Lesław; Hajkova, T.

    2012-01-01

    In general, mires develop by autogenic succession from more groundwater-fed to more rainwater-fed. This study from a calcareous mire in the West Carpathians (Slovakia) describes a similar development in the Early Holocene, followed by a reverse development in the Middle and Late Holocene. Pollen, macrofossil and testate amoeba analyses show that the site started as a minerotrophic open fen woodland. After 10 700 cal a BP autogenic succession led to the accumulation of at least 1 m of Sphagnum...

  7. Spring fen Scheuchzerio-Caricetea nigrae in the Polish Western Carpathians – vegetation diversity in relation to soil and feeding waters

    Anna Koczur

    2013-05-01

    Full Text Available The species composition of vegetation associated with the Carpathian fens primarily depends on the type of water present and the hydrological feeding of the soils that occur there. These, in turn, shape the fertility of the fens. Those with typically formed Carici-Agrostietum caninae and Valeriano-Caricetum flavae fundamentally differ in the properties of their soils and feeding waters. These include differences in mineral content, pH, CaCO3 levels, degree of peat decomposition, electrical conductivity and oxygenation of the waters that feed the fens. Carici-Agrostietum caninae is a homogenous plant association adapted to extreme habitat conditions. It is characterized by a very narrow range of essential soil and feeding water parameters. Valeriano-Caricetum flavae is a highly diverse association. Considerable diversity both in terms of plant species and vegetation structure reflects very wide ranges in the properties of soil and feeding water. Vegetation patches of transitory character were also identified. These contained plant species characteristic of both associations. The character of the vegetation depends mainly on fen soil pH and the degree of mineralization of the feeding waters. It is only these parameters that allow intermediate patches to be clearly distinguished. The degree of peat decomposition, mineral content and water oxygenation all differ for Carici-Agrostietum caninae and Valeriano-Caricetum flavae, whereas the values for intermediate patches display a range of parameters typical of both investigated associations. Consequently, vegetation present in these patches reflects to a greater or lesser extent one of the two analyzed plant associations.

  8. Un modelo matemático para fenómenos de intercambio y difusión en pañales superabsorbentes

    Estrada, Hernán; Mantilla, Ignacio; Roncancio, Weimar

    2013-01-01

    Se presenta un modelo matemático que permite estudiar dosde los fenómenos físicos que ocurren internamente en un pañal, como lo son el transporte de líquido en la celulosa y el intercambio de éste entre la celulosa y los gránulos. El desarrollo conduce a un sistema de ecuaciones diferenciales parciales, complementado con condiciones iniciales y de frontera.

  9. Slow-release carbohydrates: growing evidence on metabolic responses and public health interest. Summary of the symposium held at the 12th European Nutrition Conference (FENS 2015)

    Vinoy, Sophie; Laville, Martine; Feskens, Edith

    2016-01-01

    To draw attention to the necessity of considering differences in the digestibility of carbohydrates, and more specifically of starch, a symposium was held at the 12th European Nutrition Conference (FENS), which took place in Berlin from October 20 to 23, 2015. The purpose of this session was to present the consolidated knowledge and recent advances regarding the relationship between slow-release carbohydrates, metabolic responses, and public health issues. Three main topics were presented: 1)...

  10. Fluxes and 13C isotopic composition of dissolved carbon and pathways of methanogenesis in a fen soil exposed to experimental drought

    Knorr, K.-H.; Glaser, B.; C. Blodau

    2008-01-01

    Peatlands contain a carbon stock of global concern and significantly contribute to the global methane burden. The impact of drought and rewetting on carbon cycling in peatland ecosystems is thus currently debated. We studied the impact of experimental drought and rewetting on intact monoliths from a temperate fen over a period of ~300 days, using a permanently wet treatment and two treatments undergoing drought for 50 days. In one of the mesocosms, vegetation had been remove...

  11. Fluxes and 13C isotopic composition of dissolved carbon and pathways of methanogenesis in a fen soil exposed to experimental drought

    C. Blodau; Glaser, B.; K.-H. Knorr

    2008-01-01

    Peatlands contain a carbon stock of global concern and significantly contribute to the global methane burden. The impact of drought and rewetting on carbon cycling in peatland ecosystems is thus currently debated. We studied the impact of experimental drought and rewetting on intact monoliths from a temperate fen over a period of ~300 days, using a permanently wet treatment and two treatments undergoing drought for 50 days. In one of the mesocosms, vegetation had been removed. Net production ...

  12. Conteúdo de fenólicos, flavonoides totais e atividade antioxidante de amostras de própolis comerciais

    Elizângela Alves

    2013-01-01

    Full Text Available Neste trabalho foram determinadas algumas características físico-químicas de própolis de Santa Maria- RS. Foram analisadas seis amostras comerciais obtidas em farmácias e lojas de produtos naturais na cidade citada. A composição química, quanto aos fenólicos e flavonoides totais, assim como a atividade antioxidante, foi testada e comparada. A alta atividade antioxidante dos extratos puros (ou diluídos foi explicada pelo teor dos flavonoides e fenólicos totais, confirmando a relação desses compostos na ação preventiva contra radicais livres. As seis amostras comerciais analisadas possuíram de fenólicos 70,60 mg a 539,10 mg (expresso em mg de ácido gálico/g de extrato de própolis e de flavonoides 48,95 mg a 114,50 mg (expresso em mg de quercetina/g de extrato de própolis. A atividade antioxidante maior foi do extrato aquoso, tanto pela inibição do radical DPPH quanto pela atividade quelante. No extrato aquoso de própolis obteve-se resultados satisfatórios para uma futura aplicação em alimento.

  13. El Frente Estudiantil Nacional (FEN: juventud y estudiantado en el proceso contestatario de los años sesenta en Argentina

    Alejandra Reta

    2009-12-01

    Full Text Available Este artículo forma parte de un proyecto más amplio que aborda el proceso de acercamiento al Peronismo por parte de un sector del movimiento estudiantil en Argentina durante los años sesentas, tomando el caso particular del Frente Estudiantil Nacional (FEN. El FEN fue una organización universitaria “de pasaje al peronismo”, que buscaba inserción “legítima” en el mismo, vinculándose a sectores del peronismo histórico y al trabajo barrial.Proponemos privilegiar el análisis de documentos, aunque incluimos también algunos testimonios que nos sirven de apoyo. A partir de allí pretendemos explorar algunos “componentes contestatarios”, ligados al clima de ideas de la época, y visualizar cómo este actor colectivo se posiciona dentro de las categorías de “juventud” y del “estudiantado”, que aparecen en el discurso, considerando que el FEN reivindicó constantemente su carácter de tendencia estudiantil universitaria y su militancia juvenil.

  14. Ķīnas fen šui ģeomantikas iezīmes Heian perioda japāņu dārzos

    Gribuste, Ieva

    2016-01-01

    Darbs - “Ķīnas Fen Šui Ģeomantikas Iezīmes Heian Perioda Japāņu Dārzos” apkopo fen šui pamatidejas un apskata kā tās ir ietekmējušas un izpaužas Heian perioda dārzniecībā un ainavu arhitektūrā Japānā. Mūsdienās, ātrās informācijas apmaiņas laikmetā, aizvien lielāku popularitāti Eiropā iegūst Āzijā radusies filozofija par personīgās harmonijas sasniegšanu ar apkārtējās vides sakārtošanas palīdzību, proti, fen šui prakse. Tā ir ieguvusi īpaši lielu atsauksmi mājas interjera plānošanas ziņā, ta...

  15. Genomic Phenotyping by Barcode Sequencing Broadly Distinguishes between Alkylating Agents, Oxidizing Agents, and Non-Genotoxic Agents, and Reveals a Role for Aromatic Amino Acids in Cellular Recovery after Quinone Exposure

    Svensson, J. Peter; Quirós Pesudo, Laia; McRee, Siobhan K.; Adeleye, Yeyejide; Carmichael, Paul; Samson, Leona D.

    2013-01-01

    Toxicity screening of compounds provides a means to identify compounds harmful for human health and the environment. Here, we further develop the technique of genomic phenotyping to improve throughput while maintaining specificity. We exposed cells to eight different compounds that rely on different modes of action: four genotoxic alkylating (methyl methanesulfonate (MMS), N-Methyl-N-nitrosourea (MNU), N,N′-bis(2-chloroethyl)-N-nitroso-urea (BCNU), N-ethylnitrosourea (ENU)), two oxidizing (2-methylnaphthalene-1,4-dione (menadione, MEN), benzene-1,4-diol (hydroquinone, HYQ)), and two non-genotoxic (methyl carbamate (MC) and dimethyl sulfoxide (DMSO)) compounds. A library of S. cerevisiae 4,852 deletion strains, each identifiable by a unique genetic ‘barcode’, were grown in competition; at different time points the ratio between the strains was assessed by quantitative high throughput ‘barcode’ sequencing. The method was validated by comparison to previous genomic phenotyping studies and 90% of the strains identified as MMS-sensitive here were also identified as MMS-sensitive in a much lower throughput solid agar screen. The data provide profiles of proteins and pathways needed for recovery after both genotoxic and non-genotoxic compounds. In addition, a novel role for aromatic amino acids in the recovery after treatment with oxidizing agents was suggested. The role of aromatic acids was further validated; the quinone subgroup of oxidizing agents were extremely toxic in cells where tryptophan biosynthesis was compromised. PMID:24040048

  16. In Folio Respiratory Fluxomics Revealed by {sup 13}C Isotopic Labeling and H/D Isotope Effects Highlight the Non-cyclic Nature of the Tricarboxylic Acid 'Cycle' in Illuminated Leaves

    Tcherkez, G.; Mahe, A.; Gauthier, P.; Hodges, M. [Institut de Biotechnologie des Plantes, Plateforme Metabolisme-Metabolome IFR87, Batiment 630, Universite Paris-Sud 11, 91405 Orsay cedex (France); Tcherkez, G.; Mauve, C.; Cornic, G. [Laboratoire d' Ecophysiologie Vegetale, Ecologie Systematique Evolution (G.C.), Batiment 630, Universite Paris-Sud 11, 91405 Orsay cedex (France); Gout, E.; Bligny, R. [Laboratoire de Physiologie Cellulaire Vegetale, Commissariat a l' Energie Atomique-Grenoble, 38054 Grenoble cedex 9 (France)

    2009-07-01

    While the possible importance of the tricarboxylic acid (TCA) cycle reactions for leaf photosynthesis operation has been recognized, many uncertainties remain on whether TCA cycle biochemistry is similar in the light compared with the dark. It is widely accepted that leaf day respiration and the metabolic commitment to TCA decarboxylation are down-regulated in illuminated leaves. However, the metabolic basis (i.e. the limiting steps involved in such a down-regulation) is not well known. Here, we investigated the in vivo metabolic fluxes of individual reactions of the TCA cycle by developing two isotopic methods, {sup 13}C tracing and fluxomics and the use of H/D isotope effects, with Xanthium strumarium leaves. We provide evidence that the TCA 'cycle' does not work in the forward direction like a proper cycle but, rather, operates in both the reverse and forward directions to produce fumarate and glutamate, respectively. Such a functional division of the cycle plausibly reflects the compromise between two contrasted forces: (1) the feedback inhibition by NADH and ATP on TCA enzymes in the light, and (2) the need to provide pH-buffering organic acids and carbon skeletons for nitrate absorption and assimilation. (authors)

  17. CO{sub 2} exchange of a sedge fen in southern Finland - the impact of a drought period

    Aurela, Mika; Laurila, Tuomas; Tuovinen, Juha-Pekka [Finnish Meteorological Inst., Helsinki(Finland)]. e-mail: mika.aurela@fmi.fi; Riutta, Terhi; Tuittila, Eeva- Stiina [Dept. of Forest Ecology, Univ. of Helsinki, Helsinki (Finland); Vesala, Timo; Rinne, Janne; Haapanala, Sami [Dept. of Physical Sciences, Univ. of Helsinki, Helsinki( FI); Laine, Jukka [Finnish Forest Research Inst., Parkano Research Unit, Parkan o (Finland)

    2007-11-15

    Eddy covariance (EC) measurements of net ecosystem CO{sub 2} exchange (NEE) were conducted on a boreal sedge fen in southern Finland (61 deg 50 N, 24 deg 12 E) during a 1.5-yr period covering two summers in 2004-2005. The EC data were complemented by chamber measurements, which enabled the partition of the daytime NEE into respiration and photosynthesis. A special emphasis was put on the hydrometeorological responses of CO{sub 2} exchange during a drought period in July 2005. A mean CO{sub 2} efflux of 0.009 mgCO{sub 2} /m{sup 2}/s was observed during mid-winter (January-February), while the night-time respiration during the two Julys averaged 0.09 mgCO{sub 2} /m{sup 2}/s. During both years the mean mid-day uptake in late July was about -0.16 mgCO{sub 2} /m{sup 2}/s. An annual CO{sub 2} balance of -188 gCO{sub 2}/m{sup 2} was observed in 2005. A slightly higher net sink of -219 gCO{sub 2}/m{sup 2} was estimated for 2004. The drought period experienced in July 2005 caused a clear depression in the daily NEE values. From the combined analysis of EC and chamber measurements it was concluded that this was mainly due to increased respiration, but evidence was also found of suppressed photosynthesis due to a high VPD.

  18. Storage and release of road-salt contamination from a calcareous lake-basin fen, western Massachusetts, USA.

    Rhodes, Amy L; Guswa, Andrew J

    2016-03-01

    Road salt (NaCl) applications to highways have increased stream sodium and chloride concentrations due to retention within watersheds. The mechanisms for retention and export of Na(+) and Cl(-) from different environments are not fully understood. This field study examines the hydrologic and cation exchange processes that store and release Na(+) and Cl(-) from a calcareous fen adjacent to a highway. Despite high concentrations of Ca(2+) and Mg(2+), elevated salt concentrations enable Na(+) to occupy up to 15% of the cation exchange capacity of shallow peat. Calculations of selectivity coefficients show that Na(+) preferentially exchanges with Mg(2+), and Na(+) can be desorbed under more dilute conditions caused by precipitation and snowmelt. Detailed sampling of surface and ground waters during three snowmelt events illustrate early releases of Na(+) and Cl(-) at the onset of melting, with maximum fluxes coinciding with peak discharge. From 7 March through 4 April 2005, the flux of dissolved salt exiting the wetland amounts to 13% (Na) and 17% (Cl) of annual rock salt applied to the highway. For all of 2005, the total salt mass leaving the wetland via Kampoosa Brook is similar to the amount of road salt applied; 50% of the annual salt efflux occurred during the snowmelt season of March through May. In general, exported Na(+) and Cl(-) correlate with the number of lane miles of highway crossing the watershed. Large rain events outside of winter months are more effective than snowmelt with reducing dissolved salts because snowmelt also introduces contamination. For this and other wetlands having alkaline geochemistry and high flushing rates, management strategies that reduce rock salt amounts to roadways will assist with reducing salt contamination to levels less toxic to vegetation and aquatic organisms. PMID:26760273

  19. The hydrogeologic connectivity of a low-flow saline-spring fen peatland within the Athabasca oil sands region, Canada

    Wells, Corey M.; Price, Jonathan S.

    2015-12-01

    Saline springs can provide clues as to the nature of groundwater flow, including how it relates to subsurface wastewater storage and the distribution of solutes in the landscape. A saline-spring peatland neighboring a proposed in-situ oil facility was examined near Fort McMurray, Alberta (Canada). The study area is situated just north of a saline groundwater discharge zone, which coincides with the erosional edge of the Cretaceous Grand Rapids Formation. Na+ (mean 6,949 mg L-1) and Cl- (mean 13,776 mg L-1) were the dominant salts within the peatland, which increased by an order of magnitude in the opposite direction to that of the local groundwater flow. Rivers and freshwater wetlands within the study area had anomalously high salinities, in some cases exceeding 10,000 mg L-1 total dissolved solids within deeper sediments. Saline-spring features were observed as far as 5 km from the study area. A low-permeability mineral layer underlying the peatland restricted vertical groundwater exchange (estimated to be less than several mm over the 4-month study period). Sand and gravel lenses underlying the fen's high-salinity zone may function as areas of enhanced discharge. High Cl/Br ratios point to halite as a potential source of salinity, while δ18O and δ2H signatures in groundwater were lower than modern-day precipitation or Quaternary aquifers. The complex connectivity of saline-spring wetlands within the landscape has implications for industry and land-use managers, and justifies incorporating them into monitoring networks to better gauge the magnitude and flow history of natural saline discharge in the oil sands region.

  20. Amino acids

    Amino acids are organic compounds that combine to form proteins . Amino acids and proteins are the building blocks of life. When proteins are digested or broken down, amino acids are left. The human body uses amino acids ...

  1. Hydrological Controls on Ecosystem CO2 and CH4 Exchange in a MIXED Tundra and a FEN within an Arctic Landscape UNDER Current and Future Climates

    Grant, R. F.; Humphreys, E.; Lafleur, P.

    2014-12-01

    Variation in CO2 and CH4 exchange in years with contrasting weather is strongly affected by hydrology in landscapes underlain by permafrost. Hypotheses for this variation were incorporated into the ecosystem model ecosys which simulated CO2 and CH4 fluxes along a topographic gradient within an arctic landscape at Daring Lake, NWT, Canada. Fluxes modelled at mixed tundra and fen sites within the gradient were compared with CO2 fluxes measured at eddy covariance towers from 2006 to 2009, and with CH4 fluxes measured with surface chambers in 2008. Slopes and correlation coefficients from regressions of modelled vs. measured CO2 fluxes were 1.0 ± 0.1 and 0.7 - 0.8 for both sites in all years. At the mixed tundra site, rises in net CO2 uptake in warmer years with earlier snowmelt were constrained by midafternoon declines in CO2 influxes when vapor pressure deficits (D) exceeded 1.5 kPa, and by rises in CO2 effluxes with greater active layer depth (ALD). Consequently annual net CO2 uptake at this site rose little with warming. At the fen site, CO2 influxes declined less with D and CO2 effluxes rose less with warming, so that rises in net CO2 uptake in warmer years were greater than those at the mixed tundra site. The greater declines in CO2 influxes with warming at the mixed tundra site were modelled from greater soil-plant-atmosphere water potential gradients that developed in drier soil, and the smaller rises in CO2 effluxes with warming at the fen site were modelled from O2 constraints to heterotrophic and below-ground autotrophic respiration that limited their responses to greater ALD. Modelled and measured CH4 exchange during July and August indicated very small influxes at the mixed tundra site, and larger emissions at the fen site. Emissions of CH4 modelled during soil freezing in October - November contributed about one-third of the annual total, and so should be included in estimates of annual emissions. These contrasting responses to warming under current

  2. Atividade alelopática, antioxidante e teor de fenóis totais de Hydrocotyle bonariensis Lam. (Araliaceae = Allelopathic and antioxidant activity and total phenolic contents of Hydrocotyle bonariensis Lam. (Araliaceae

    Cristiane Bezerra Silva

    2010-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a atividade alelopática, antioxidante e o teor de fenóis totais de Hydrocotyle bonariensis. A bioatividade do extrato bruto e frações (hexânica, acetato de etila e etanol-água da parte aérea e subterrânea e fração alcaloídica obtidas do extrato bruto (parte subterrânea de H. bonariensis, foram avaliadas em bioensaios de germinação e crescimento de alface, tomate, cebola e trigo, em laboratório. O teor de fenóis totais foi determinado pelo método de Folin–Ciocalteu. A atividade antioxidante foi avaliada usando o 2,2-diphenyl-1-picrylhydrazyl (DPPH. Os resultados revelaram que os extratos e frações inibiram a germinação de alface, tomate, cebola, e trigo. A fração acetato de etila daparte subterrânea inibiu a germinação de alface em 68% e de trigo em 60%. Nos bioensaios de crescimento, a fração acetato de etila da parte aérea e subterrânea apresentou os maiores efeitos inibitórios no crescimento da raiz (> 40%, hipocótilo/coleóptilo (> 40% e massaseca. Sendo a fração acetato de etila da parte subterrânea a que apresentou os maiores teores de fenóis totais, a mais ativa frente ao radical DPPH e também a fração com maior efeito fitotóxico na germinação e crescimento de alface, tomate, cebola e trigo.The aim of this work was to evaluate the allelophathic and antioxidant activity and the total phenolic contents of Hydrocotylebonariensis. The bioactivity of the crude extract and fractions (hexane, ethyl acetate, ethanolwater of aerial and underground parts and the alkaloid fraction from underground part of H. bonariensis were evaluated by germination and growth bioassays with lettuce, tomato, onion and wheat, in laboratory. The total phenolic contents were determined by the Folin- Ciocalteau method. Antioxidant activity was evaluated using the 2,2-diphenyl-1- picrylhydrazyl (DPPH. The results revealed that the extract and fractions inhibited the germination of lettuce

  3. Oncogenicity of L-type amino-acid transporter 1 (LAT1) revealed by targeted gene disruption in chicken DT40 cells: LAT1 is a promising molecular target for human cancer therapy

    Highlights: → We established LAT1 amino-acid transporter-disrupted DT40 cells. → LAT1-disrupted cells showed slow growth and lost the oncogenicity. → siRNA and mAb inhibited human tumor growth in vitro and in vivo. → LAT1 is a promising target molecule for cancer therapy. -- Abstract: L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4 kb. We established five homozygous LAT1-disrupted (LAT1-/-) cell clones, derived from a heterozygous LAT1+/- clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1-/- DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1-/- cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1-/- DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1-/- DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1+/- DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy.

  4. Analysis of the structure of mycolic acids of Mycobacterium simiae reveals a particular composition of alpha-mycolates in strain 'habana' TMC 5135, considered as immunogenic in tuberculosis and leprosy.

    Mederos, Lilian; Valdivia, José A; Valero-Guillén, Pedro L

    2007-12-01

    Structural analysis of mycolic acids from Mycobacterium simiae (including some 'habana' strains) was carried out using (1)H-NMR and MS. Results indicated that this species presents a general pattern of alpha-, alpha'- and keto-mycolates. alpha-Mycolates were composed of a complex mixture of 82 to 89 carbon atoms (C82-C89), with the predominant molecular species containing two di-substituted cyclopropane rings. Among keto-mycolates (C84-C89), those containing one trans di-substituted cyclopropane ring were the most abundant. The alpha'-mycolates were monounsaturated (C64, C66). According to MS and (1)H-NMR data, the strains studied differed in fine structural details of alpha-mycolates and keto-mycolates. Notably, strain 'habana' TMC 5135 (belonging to the 'habana' group, and considered as highly immunogenic in tuberculosis and leprosy) presented a particular composition of alpha-mycolates, with a major component (C87) containing one cis plus one trans di-substituted cyclopropane ring, unlike the type strain of M. simiae and other strains of the 'habana' group (IPK-220 and IPK-337R), in which the major component (C84) contained two cis di-substituted cyclopropane rings. In spite of this finding, the 'habana' strains were closely related to each other and mainly differed from the type strain of M. simiae in some details of the fine structure of keto-mycolates. The present work indicated that within an identical general pattern of mycolic acids, there is a complex composition in M. simiae and structural variation among different strains, as reported for pathogenic species of the genus. Noteworthy was the particular composition of alpha-mycolates in strain 'habana' TMC 5135. PMID:18048929

  5. The crystal structure of a xyloglucan-specific endo-beta-1,4-glucanase from Geotrichum sp. M128 xyloglucanase reveals a key amino acid residue for substrate specificity.

    Yaoi, Katsuro; Kondo, Hidemasa; Hiyoshi, Ayako; Noro, Natsuko; Sugimoto, Hiroshi; Tsuda, Sakae; Miyazaki, Kentaro

    2009-09-01

    Geotrichum sp. M128 possesses two xyloglucan-specific glycoside hydrolases belonging to family 74, xyloglucan-specific endo-beta-1,4-glucanase (XEG) and oligoxyloglucan reducing-end-specific cellobiohydrolase (OXG-RCBH). Despite their similar amino acid sequences (48% identity), their modes of action and substrate specificities are distinct. XEG catalyzes the hydrolysis of xyloglucan polysaccharides in endo mode, while OXG-RCBH acts on xyloglucan oligosaccharides at the reducing end in exo mode. Here, we determined the crystal structure of XEG at 2.5 A resolution, and compared it to a previously determined structure of OXG-RCBH. For the most part, the amino acid residues that interact with substrate are conserved between the two enzymes. However, there are notable differences at subsite positions -1 and +2. OXG-RCBH has a loop around the +2 site that blocks one end of the active site cleft, which accounts for its exo mode of action. In contrast, XEG lacks a corresponding loop at this site, thereby allowing binding to the middle of the main chain of the substrate. At the -1 site in OXG-RCBH, Asn488 interacts with the xylose side chain of the substrate, whereas the -1 site is occupied by Tyr457 in XEG. To confirm the contribution of this residue to substrate specificity, Tyr457 was substituted by Gly in XEG. The wild-type XEG cleaved the oligoxyloglucan at a specific site; the Y457G variant cleaved the same substrate, but at various sites. Together, the absence of a loop in the cleft and the presence of bulky Tyr457 determine the substrate specificity of XEG. PMID:19682300

  6. Pyometra u fen

    Klimešová, Vanda

    2012-01-01

    This bachelor thesis deals with female dogs' disorders of pyometra and its problems. The aim of this thesis is to provide comprehensive information on this serious disorder of the reproductive system. A part of the thesis is also a questionnaire survey that is concerned with the disease itself and also with the owners' knowledge of the female dog diseases. Pyometra is an inflammatory disease of the uterus. In most cases, the disease is caused by the persistent production of progesteron...

  7. A transcript profiling approach reveals an abscisic acid-specific glycosyltransferase (UGT73C14 induced in developing fiber of Ligon lintless-2 mutant of cotton (Gossypium hirsutum L..

    Matthew K Gilbert

    Full Text Available Ligon lintless-2, a monogenic dominant cotton (Gossypium hirsutum L. fiber mutation, causing extreme reduction in lint fiber length with no pleiotropic effects on vegetative growth, represents an excellent model system to study fiber elongation. A UDP-glycosyltransferase that was highly expressed in developing fibers of the mutant Ligon lintless-2 was isolated. The predicted amino acid sequence showed ~53% similarity with Arabidopsis UGT73C sub-family members and the UDP-glycosyltransferase was designated as UGT73C14. When expressed in Escherichia coli as a recombinant protein with a maltose binding protein tag, UGT73C14 displayed enzymatic activity toward ABA and utilized UDP-glucose and UDP-galactose as the sugar donors. The recombinant UGT73C14 converted natural occurring isoform (+-cis, trans-ABA better than (+-trans, trans-ABA and (--cis, trans-ABA. Transgenic Arabidopsis plants constitutively overexpressing UGT73C14 did not show phenotypic changes under standard growth conditions. However, the increased glycosylation of ABA resulted in phenotypic changes in post-germinative growth and seedling establishment, confirming in vivo activity of UGT73C14 for ABA. This suggests that the expression level of UGT73C14 is regulated by the observed elevated levels of ABA in developing fibers of the Li 2 mutant line and may be involved in the regulation of ABA homeostasis.

  8. The Structure of the Cyprinid herpesvirus 3 ORF112-Zα·Z-DNA Complex Reveals a Mechanism of Nucleic Acids Recognition Conserved with E3L, a Poxvirus Inhibitor of Interferon Response.

    Kuś, Krzysztof; Rakus, Krzysztof; Boutier, Maxime; Tsigkri, Theokliti; Gabriel, Luisa; Vanderplasschen, Alain; Athanasiadis, Alekos

    2015-12-25

    In vertebrate species, the innate immune system down-regulates protein translation in response to viral infection through the action of the double-stranded RNA (dsRNA)-activated protein kinase (PKR). In some teleost species another protein kinase, Z-DNA-dependent protein kinase (PKZ), plays a similar role but instead of dsRNA binding domains, PKZ has Zα domains. These domains recognize the left-handed conformer of dsDNA and dsRNA known as Z-DNA/Z-RNA. Cyprinid herpesvirus 3 infects common and koi carp, which have PKZ, and encodes the ORF112 protein that itself bears a Zα domain, a putative competitive inhibitor of PKZ. Here we present the crystal structure of ORF112-Zα in complex with an 18-bp CpG DNA repeat, at 1.5 Å. We demonstrate that the bound DNA is in the left-handed conformation and identify key interactions for the specificity of ORF112. Localization of ORF112 protein in stress granules induced in Cyprinid herpesvirus 3-infected fish cells suggests a functional behavior similar to that of Zα domains of the interferon-regulated, nucleic acid surveillance proteins ADAR1 and DAI. PMID:26559969

  9. Quantitative three-dimensional analysis of poly (lactic-co-glycolic acid) microsphere using hard X-ray nano-tomography revealed correlation between structural parameters and drug burst release.

    Huang, Xiaozhou; Li, Na; Wang, Dajiang; Luo, Yuyan; Wu, Ziyu; Guo, Zhefei; Jin, Qixing; Liu, Zhuying; Huang, Yafei; Zhang, Yongming; Wu, Chuanbin

    2015-08-10

    The objective of this study was to investigate the use of transmission hard X-ray nano-computed-tomography (nano-CT) for characterization of the pore structure and drug distribution in poly (lactic-co-glycolic acid) (PLGA) microspheres encapsulating bovine serum albumin and to study the correlation between drug distribution and burst release. The PLGA microspheres were fabricated using a double-emulsion method. The results of pore structure analysis accessed with nano-CT were compared with those acquired by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Surface pore interconnectivity and surface protein interconnectivity were obtained using combined nano-CT and pixel analysis. The correlation between surface protein interconnectivity with the initial burst release across various tested formulations was also analyzed. The size, shape, and distribution of the pores and protein could be clearly observed in the whole microsphere using nano-CT, whereas only the sectional information was observed using SEM or CLSM. Interconnected pores and surface connected pores could be clearly distinguished in nano-CT, which enables the quantitative analysis of surface pore interconnectivity and surface protein interconnectivity. The surface protein interconnectivity in different formulations correlated well with the burst release at 5-10h. Nano-CT provided a nondestructive, high-resolution, and three-dimensional analysis method to characterize the porous microsphere. PMID:25951620

  10. First Principles Calculations of Aqueous pKa Values for Organic and Inorganic Acids Using COSMO-RS Reveal an Inconsistency in the Slope of the pKa Scale.

    Klamt, Andreas; Eckert, Frank; Diedenhofen, Michael; Beck, Michael E

    2003-11-01

    The COSMO-RS method, a combination of the quantum chemical dielectric continuum solvation model COSMO with a statistical thermodynamics treatment for more realistic solvation (RS) simulations, has been used for the direct prediction of pKa constants of a large variety of 64 organic and inorganic acids. A highly significant correlation of r(2) = 0.984 with a standard deviation of only 0.49 between the calculated values of the free energies of dissociation and the experimental pKa values was found, without any special adjustment of the method. Thus, we have a theoretical a priori prediction method for pKa, which has the regression constant and the slope as only adjusted parameters. Such a method can be of great value in many areas of physical chemistry, especially in pharmaceutical and agrochemical industry. To our surprise, the slope of pKa vs ΔGdiss is only 58% of the theoretically expected value of 1/RTln(10). A careful analysis with respect to different contributions as well as a comparison with the work of other authors excludes the possibility that the discrepancy is due to weaknesses of the calculation method. Hence, we must conclude that the experimental pKa scale depends differently on the free energy of dissociation than generally assumed. PMID:26313337

  11. High net CO2 and CH4 release at a eutrophic shallow lake on a formerly drained fen

    Franz, Daniela; Koebsch, Franziska; Larmanou, Eric; Augustin, Jürgen; Sachs, Torsten

    2016-05-01

    Drained peatlands often act as carbon dioxide (CO2) hotspots. Raising the groundwater table is expected to reduce their CO2 contribution to the atmosphere and revitalise their function as carbon (C) sink in the long term. Without strict water management rewetting often results in partial flooding and the formation of spatially heterogeneous, nutrient-rich shallow lakes. Uncertainties remain as to when the intended effect of rewetting is achieved, as this specific ecosystem type has hardly been investigated in terms of greenhouse gas (GHG) exchange. In most cases of rewetting, methane (CH4) emissions increase under anoxic conditions due to a higher water table and in terms of global warming potential (GWP) outperform the shift towards CO2 uptake, at least in the short term.Based on eddy covariance measurements we studied the ecosystem-atmosphere exchange of CH4 and CO2 at a shallow lake situated on a former fen grassland in northeastern Germany. The lake evolved shortly after flooding, 9 years previous to our investigation period. The ecosystem consists of two main surface types: open water (inhabited by submerged and floating vegetation) and emergent vegetation (particularly including the eulittoral zone of the lake, dominated by Typha latifolia). To determine the individual contribution of the two main surface types to the net CO2 and CH4 exchange of the whole lake ecosystem, we combined footprint analysis with CH4 modelling and net ecosystem exchange partitioning.The CH4 and CO2 dynamics were strikingly different between open water and emergent vegetation. Net CH4 emissions from the open water area were around 4-fold higher than from emergent vegetation stands, accounting for 53 and 13 g CH4 m-2 a-1 respectively. In addition, both surface types were net CO2 sources with 158 and 750 g CO2 m-2 a-1 respectively. Unusual meteorological conditions in terms of a warm and dry summer and a mild winter might have facilitated high respiration rates. In sum, even after 9

  12. Análisis de fenómenos de localización en materiales cohesivo-friccionales

    Martínez Cutillas, Francisco J.

    1994-08-01

    Full Text Available The growth of the finite element method as a tool in structural analysis requires the use of concrete models capable of exhibiting responses beyond the elastic range. In recent years, considerable interest has arisen in the characterization and modeling of materials which include a softening phase in their mechanical behaviour. This softening is often related to the interaction between microstructural components of the material, which results in the generation of non-homogeneous strain states where deformations are localized in relatively thin bands. The object of this work is to contribute to the numerical analysis of the phenomenon of strain localization as it arises in cohesive frictional materials. Special attention is paid to the behaviour of mass concrete and, particularly, to its characterization and modeling during uniaxial compression.

    El creciente empleo del método de los elementos finitos como herramienta de cálculo estructural requiere la definición de modelos de hormigón capaces de reproducir respuestas más allá del rango eminentemente elástico. En los últimos años ha crecido fuertemente el interés en la caracterización y modelización de materiales cuyo comportamiento mecánico incluye una fase de reblandecimiento en las etapas próximas a la rotura. En muchos casos dicho reblandecimiento está asociado a la interacción entre los componentes microestructurales del material que genera estados de deformación no homogéneos con una localización de las deformaciones en bandas de pequeño espesor. El objeto del presente trabajo es contribuir al análisis por métodos numéricos del fenómeno de localización de deformaciones en materiales cohesivo fricciónales. Se dedica especial atención al hormigón en masa y, de manera particular, a la caracterización y modelización de su comportamiento en compresión uniaxial.

  13. Organic sediment formed during inundation of a degraded fen grassland emits large fluxes of CH4 and CO2

    A. Freibauer

    2010-12-01

    Full Text Available Peatland restoration by inundation of drained areas can alter local greenhouse gas emissions by altering rates of CO2 and CH4 emissions. Factors that can influence these emissions include the quality and amount of substrates available for anaerobic degradation processes and the sources and availability of electron acceptors. In order to learn about possible sources of high CO2 and CH4 emissions from a rewetted degraded fen grassland, we performed incubation experiments that tested the effects of fresh plant litter in the flooded peats on pore water chemistry and CO2 and CH4 production and emission. The position in the soil profile of the pre-existing drained peat substrate affected initial rates of anaerobic CO2 production subsequent to flooding, with the uppermost peat layer producing the greatest specific rates of CO2 evolution. CH4 production rates depended on the availability of electron acceptors and was significant only when sulfate concentrations were reduced in the pore waters. Very high specific rates of both CO2 (maximum of 412 mg C d−1 kg−1 C and CH4 production (788 mg C d−1 kg−1 C were observed in a new sediment layer that accumulated over 2.5 years since the site was flooded. This new sediment layer was characterized by overall low C content, but represented a mixture of sand and relatively easily decomposable plant litter from reed canary grass killed by flooding. Samples that excluded this new sediment layer but included intact roots remaining from flooded grasses had specific rates of CO2 (max. 28 mg C d−1 kg−1 C and CH4 (max. 34 mg C d−1 kg−1 C production that were 10–20 times lower, and were comparable to those of newly flooded upper peat layer. Lowest rates of anaerobic CO2 and CH4 production (range of 4–8 mg C d−1 kg−1 C and −1 kg−1 C were observed when all fresh organic matter sources (plant litter and roots were excluded. In conclusion, the presence of fresh organic substrates such as plant and

  14. Biodegradación de los compuestos fenólicos presentes en el alpechín

    Maestro Durán, R.

    1991-08-01

    Full Text Available Oil-mill wastewater is the main responsible of the pollution in Andalusian due to high content of organic substances. Its depuration by methanization is difficult because of the antimicrobial activity of phenolic derivatives. These compounds can be drastically reduced by a previous aerobic treatment of the oil mill wastewater with specific microorganisms. After this pretreatment, anaerobic depuration takes place without inhibition, the velocity of the reaction being 5 times higher than before the pretreatment. In this paper a qualitative study of the phenols present in oil-mill wastewater by thin layer chromatography has been done. Beside that, quantitative determination of total phenols, ortoand meta-diphenols as well as Chemical Oxigen Demand (COD before the treatment, after the pretreatment and after biomethanization have been carried out. Finally, leucoanthocyanins that could originate polymerized phenols have not been found.

    Las aguas residuales de la obtención del aceite de oliva o alpechines son responsables de la mayor contaminación medioambiental de Andalucía por su elevada carga de materia orgánica. Su depuración por biometanización es difícil debido a la actividad antimicrobiana de los compuestos fenólicos. Este tipo de sustancias puede eliminarse en gran parte tratando previamente el alpechín por vía aerobia con microorganismos específicos, después de lo cual la depuración anaerobia tiene lugar sin inhibiciones, siendo la constante de velocidad cinco veces superior a la de antes del pretratamiento. En este trabajo se hace un estudio cualitativo de los fenoles por cromatografía en capa fina y cuantitativo de los fenoles totales, orto- y meta-difenoles, así como de la Demanda Química de Oxígeno del alpechín antes del tratamiento, después del pretratamiento y después de la biometanización. Se ha comprobado también la ausencia de leucoantocianinas que pudieran dar origen a fenoles polimerizados.

  15. Belowground in situ redox dynamics and methanogenesis recovery in a degraded fen during dry-wet cycles and flooding

    C. Estop-Aragonés

    2013-01-01

    Full Text Available Climate change induced drying and flooding may alter the redox conditions of organic matter decomposition in peat soils. The seasonal and intermittent changes in pore water solutes (NO3, Fe2+, SO42−, H2S, acetate and dissolved soil gases (CO2, O2, CH4, H2 under natural water table fluctuations were compared to the response under a reinforced drying and flooding in fen peats. Oxygen penetration during dryings led to CO2 and CH4 degassing and to a regeneration of dissolved electron acceptors (NO3, Fe3+ and SO42−. Drying intensity controlled the extent of the electron acceptor regeneration. Iron was rapidly reduced and sulfate pools ~ 1 mM depleted upon rewetting and CH4 did not substantially accumulate until sulfate levels declined to ~ 100 μmol L−1. The post-rewetting recovery of soil methane concentrations to levels ~ 80 μmol L−1 needed 40–50 days after natural drought. This recovery was prolonged after experimentally reinforced drought. A greater regeneration of electron acceptors during drying was not related to prolonged methanogenesis suppression after rewetting. Peat compaction, solid phase content of reactive iron and total reduced inorganic sulfur and organic matter content controlled oxygen penetration, the regeneration of electron acceptors and the recovery of CH4 production, respectively. Methane production was maintained despite moderate water table decline of 20 cm in denser peats. Flooding led to accumulation of acetate and H2, promoted CH4 production and strengthened the co-occurrence of iron and sulfate reduction and methanogenesis. Mass balances during drying and flooding indicated that an important fraction of the electron flow must have been used for the

  16. Controls of Spatial and Temporal Variability in CH4 Flux in a High Arctic Fen over Three Years

    Strom, L.; Falk, J. M.; Skov, K.; Jackowicz-Korczynski, M.; Mastepanov, M.; Lund, M.; Christensen, T. R.; Schmidt, N. M.

    2014-12-01

    Arctic wetlands are an important source of CH4 to the atmosphere and store large amounts of carbon as peat. The aim of this study was to determine the main driving forces of the spatial variability in CH4 flux in a high arctic fen situated in Zackenberg, NE Greenland. The study was conducted over three years (2011-2013) and included 16-20 control plots and in 2013 also 29 "treated" plots, e.g., excluded muskoxen grazing (10), snow fence (9) and automated chamber (10). The plots were distributed over a 0.25 km2 area. From 1 July to 10 August we measured (all variables only in 2013) fluxes of CH4 and CO2 (NEE, Reco and GPP), temperature, water table and active layer depth, PAR, substrate conc. for CH4 production in pore-water (i.e. acetate, AA) and the species composition and density of sedges. We found significant treatment effects, a 1.8-times difference in CH4 flux between the years and a high spatial variability, e.g., 9- and 35-times difference between max and min plots depending on year and treatment. GPP was consistently a strong driver of the variability in CH4 flux. In 2013 several plant productivity related variables were singled out as the strongest drivers of the variability in CH4 flux, e.g., (in order of strength) NEE, GPP and AA. The driver of NEE, GPP and AA was the density of Eriophorum scheuchzeri. The drivers were the same and followed the same patterns irrespective of treatment. In conclusion, the results show a strong dependence of the spatial variability in CH4 flux on productivity and carbon input to vegetation and pore-water. The main driver of this input is the vegetation composition and density. The results indicate that future environmental changes in wet arctic ecosystems that affect the vegetation composition and productivity will have large impacts on their carbon balance and CH4 flux, irrespective of whether these changes are driven directly by climate change or by indirect effects on for instance grazing pressure.

  17. Crystal Structures of the Staphylococcal Toxin SSL5 in Complex With Sialyl-Lewis X Reveal a Conserved Binding Site That Shares Common Features With Viral And Bacterial Sialic Acid-Binding Proteins

    Baker, H.M.; Basu, I.; Chung, M.C.; Caradoc-Davies, T.; Fraser, J.D.; Baker, E.N.

    2009-06-02

    Staphylococcus aureus is a significant human pathogen. Among its large repertoire of secreted toxins is a group of staphylococcal superantigen-like proteins (SSLs). These are homologous to superantigens but do not have the same activity. SSL5 is shown here to bind to human granulocytes and to the cell surface receptors for human IgA (Fc alphaRI) and P-selectin [P-selectin glycoprotein ligand-1 (PSGL-1)] in a sialic acid (Sia)-dependent manner. Co-crystallization of SSL5 with the tetrasaccharide sialyl Lewis X (sLe(X)), a key determinant of PSGL-1 binding to P-selectin, led to crystal structures of the SSL5-sLe(X) complex at resolutions of 1.65 and 2.75 A for crystals at two pH values. In both structures, sLe(X) bound to a specific site on the surface of the C-terminal domain of SSL5 in a conformation identical with that bound by P-selectin. Conservation of the key carbohydrate binding residues indicates that this ability to bind human glycans is shared by a substantial subgroup of the SSLs, including SSL2, SSL3, SSL4, SSL5, SSL6, and SSL11. This indicates that the ability to target human glycans is an important property of this group of toxins. Structural comparisons also showed that the Sia binding site in SSL5 contains a substructure that is shared by other Sia binding proteins from bacteria as well as viruses and represents a common binding motif.

  18. Ecosystem CO2 and CH4 exchange in a mixed tundra and a fen within a hydrologically diverse Arctic landscape: 1. Modeling versus measurements

    Grant, R. F.; Humphreys, E. R.; Lafleur, P. M.

    2015-07-01

    CO2 and CH4 exchange are strongly affected by hydrology in landscapes underlain by permafrost. Hypotheses for these effects in the model ecosys were tested by comparing modeled CO2 and CH4 exchange with CO2 fluxes measured by eddy covariance from 2006 to 2009, and with CH4 fluxes measured with surface chambers in 2008, along a topographic gradient at Daring Lake, NWT. In an upland tundra, rises in net CO2 uptake in warmer years were constrained by declines in CO2 influxes when vapor pressure deficits (D) exceeded 1.5 kPa and by rises in CO2 effluxes with greater active layer depth. Consequently, net CO2 uptake rose little with warming. In a lowland fen, CO2 influxes declined less with D and CO2 effluxes rose less with warming, so that rises in net CO2 uptake were greater than those in the tundra. Greater declines in CO2 influxes with warming in the tundra were modeled from greater soil-plant-atmosphere water potential gradients that developed under higher D in drained upland soil, and smaller rises in CO2 effluxes with warming in the fen were modeled from O2 constraints to heterotrophic and belowground autotrophic respiration from a shallow water table in poorly drained lowland soil. CH4 exchange modeled during July and August indicated very small influxes in the tundra and larger effluxes characterized by afternoon emission events caused by degassing of warming soil in the fen. Emissions of CH4 modeled from degassing during soil freezing in October-November contributed about one third of the annual total.

  19. Atividade antimicrobiana, antioxidante e teor de compostos fenólicos em casca e amêndoa de frutos de manga

    Kettelin Aparecida Arbos

    2013-04-01

    Full Text Available O processamento industrial de frutos de manga gera elevada quantidade de resíduos agroindustriais, representados pelas cascas e sementes (amêndoa, os quais, sem aplicação viável, acabam sendo descartados diretamente no meio ambiente. Esses resíduos são ricos em compostos bioativos, amplamente reconhecidos pelas suas propriedades promotoras da saúde e em aplicações tecnológicas. Os objetivos foram avaliar as atividades antimicrobiana e antioxidante e o teor de compostos fenólicos de dois extratos: um obtido da casca (FC e outro da amêndoa (FA de manga variedade 'Tommy Atkins'. O teor de compostos fenólicos totais variou de 3.123 a 6.644 mg de catequina/100 g. Os extratos FC e FA demonstraram relevante atividade antimicrobiana frente às cepas das bactérias Escherichia coli, Salmonella sp., Pseudomonas aeruginosa . Staphylococcus aureus, determinadas pelo método de difusão em disco. A ação antioxidante de FC e FA aumentou com o aumento das concentrações testadas, atingindo o valor máximo de 88% (FC. Em todas as concentrações testadas os extratos FC apresentaram ação antioxidante significativamente superior às respectivas concentrações dos extratos FA. Esses resultados sugerem potencial aplicação dos resíduos de manga como fonte de compostos fenólicos, substâncias antimicrobianas e antioxidantes, podendo ser explorados pelas indústrias de alimentos.

  20. Widespread occurrence of the tfd-II genes in soil bacteria revealed by nucleotide sequence analysis of 2,4-dichlorophenoxyacetic acid degradative plasmids pDB1 and p712.

    Kim, Dong-Uk; Kim, Min-Sun; Lim, Jong-Sung; Ka, Jong-Ok

    2013-05-01

    Variovorax sp. strain DB1 and Pseudomonas pickettii strain 712 are 2,4-dicholorophenoxy-acetic acid (2,4-D)-degrading bacteria, which were isolated from agricultural soils in Republic of Korea and USA, respectively. Each strain harbors a 2,4-D degradative plasmid and is able to utilize 2,4-D as the sole source of carbon for its growth. The 2,4-D degradative plasmid pDB1 of strain DB1 consisted of a 65,269-bp circular molecule with a G+C content of 66.23% and had 68 ORFs. The 2,4-D degradative plasmid p712 of strain 712 was composed of a 62,798-bp circular molecule with a 62.11% G+C content and had 62 ORFs. The plasmids pDB1 and p712 share significantly homologous 2,4-D degradative genes with high similarity to the tfdR, tfdB-II, tfdC-II, tfdD-II, tfdE-II, tfdF-II, tfdK and tfdA genes of plasmid pJP4 of Alcaligenes eutrophus isolated from Australia. In a phylogenetic analysis with trfA, traL, and trbA genes, pDB1 belonged to IncP-1β with pJP4, while p712 belonged to IncP-1ε with pKJK5 and pEMT3. The results indicated that, in spite of the differences in their backbone regions, the 2,4-D catabolic genes of the two plasmids were closely related and also related to the well-known 2,4-D degradative plasmid pJP4 even though all were isolated from different geographic regions. Other similarities in the genetic organization and the presence of IS1071 suggested that these catabolic genes may be on a transposable element, leading to widespread occurrence in soil bacteria. PMID:23376020

  1. El fenómeno delictivo juvenil de la mara: Un estudio regional en Chiapas/The mara youth criminal phenomenon: A regional study in Chiapas

    Jorge Humberto Martínez Trejo; Verónica C. Castellanos León

    2013-01-01

    El objetivo de la presente investigación es comprender el fenómeno de la tropicalización de la organización delictiva juvenil de La Mara en la región de Chiapas. El desarrollo de la misma, es eminentemente de corte etnometodológico, y se encuentra actualmente en proceso de desarrollo. Sin embargo, se recogen evidencias parciales del perfil criminológico de los miembros de La Mara de Centroamérica y la de Chiapas. Dichos estudios se realizaron en el período de junio del 2011 a junio del 2012, ...

  2. El homeschooling en España : descripción y análisis del fenómeno

    Cabo González, Carlos

    2012-01-01

    El contenido del presente trabajo de tesis se estructura en torno a cuatro grandes apartados o capítulos. En el primero de ellos, se fijan los objetivos del trabajo; se establece la metodología; se delimitan los conceptos más frecuentemente utilizados en el estudio (educación, enseñanza, formación e instrucción); se define el fenómeno de la no escolarización; se informa de las diferentes denominaciones de esta práctica educativa; y, finalmente se ofrece un panorama de la situación en la qu...

  3. A adolescência enquanto fenômeno social: possibilidades e necessidades de investigação científica em enfermagem

    Maria Amélia de Campos Oliveira

    1993-03-01

    Full Text Available Recortando para além dos critérios crono-biológicos, ou seja, compreendendo-a enquanto um fenômeno social, as autoras discutem a redefinição deste objeto para investigação em enfermagem. Com isso, propõem a ampliação do leque de conhecimentos sobre a saúde do adolescente a fim de subsidiar a transformação do perfil de saúde-doença desse grupo populacional.

  4. Fenóis derivados da lignina, carboidratos e aminoaçúcares em serapilheira e solos cultivados com eucalipto em sistemas convencional e fertirrigado

    Rodinei Facco Pegoraro; Ivo Ribeiro Silva; Roberto Ferreira Novais; Nairan Felix Barros; Sebastião Fonseca

    2013-01-01

    Este estudo teve por objetivo avaliar os teores de fenóis derivados de lignina, carboidratos e aminoaçúcares, bem como o estádio de decomposição e a contribuição de compostos de origens vegetal e microbiana para a matéria orgânica do solo (MOS) em sistemas de cultivo convencional e fertirrigado de eucalipto. Foram realizadas coletas de serapilheira e solo (Argissolo) em dois sistemas de cultivo de eucalipto (convencional e fertirrigado) em dois locais de coleta (linha e entrelinha), com três ...

  5. Analogías de redes eléctricas como herramienta educativa para el estudio de diversos fenómenos físicos

    Gómez Lopera, Salvador Ángel; Cerro Velázquez, Francisco del; Alhama López, Francisco

    2005-01-01

    La resolución de problemas correspondientes a fenómenos físicos regidos por ecuaciones diferenciales en derivadas parciales, lineales o no, implica un conocimiento profundo de cálculo analítico o numérico por lo que, en general, estos problemas no se encuentran al alcance de los alumnos de facultades de ciencias o escuelas de ingeniería, desconocedores en su fase de formación de estas modernas y complejas técnicas matemáticas.A pesar de ello, es posible, en muchos casos, abordar la resolución...

  6. A fragmentação do eu na esquizofrenia e o fenômeno do transitivismo: um caso clínico

    Luciane Loss Jardim

    2011-01-01

    Full Text Available En este artículo buscamos entender la fragmentación del yo en el cuadro clínico de la esquizofrenia desde una lectura psicoanalítica. Por lo tanto, se presenta una breve digresión histórica del concepto de esquizofrenia por Eugene Bleuler destacando su propuesta sobre la escisión del yo y su visión más complexa de la psicopatología que es consistente con la teoría de la disolución imaginaria de Jacques Lacan acerca del yo en la psicosis. Entonces, se presenta el caso de Julio, un paciente esquizofrénico, que es un caso paradigmático para la comprensión de los síntomas, desde el marco psicoanalítico que presupone la existencia de formaciones inconscientes en la organización de la psicopatología de la esquizofrenia. El caso clínico se analiza en dos segmentos, es decir, el momento de la aparición de la psicosis vinculada con la falta en la estructura simbólica en relación a la función paterna. La falta del padre simbólico desencadena una disolución del yo en la psicosis, entonces, muchos de los fenómenos encontrados en la esquizofrenia es la fragmentación del yo. Julio presenta una identificación imaginaria colmada al otro, una captación por la imagen del otro, sin exclusión recíproca inherente al fenómeno del transitivismo El fenómeno del transitivismo ocurre en el estadio del espejo y aparece en determinados momentos del desarrollo psíquico, que se caracteriza por este momento de báscula, donde las acciones del niño y su semejante son iguales. Por lo tanto, la articulación entre el fenómeno del transitivismo y los síntomas de la esquizofrenia nos permite hacer una lectura de la de la psicosis a partir de este operador.

  7. Una aproximación conceptual y práctica al fenómeno del terrorismo suicida: El caso de Hezbollah

    Alba Cuéllar, Angélica

    2014-01-01

    El terrorismo suicida de carácter islamista es un fenómeno difícilmente comprensible,principalmente en el contexto de las sociedades occidentales y secularizadas, en donde es comúnmente entendido como un acto desprovisto de cualquier forma de racionalidad y enmarcado en el fanatismo religioso. No obstante, se trata de acciones que requieren del marco de organizaciones, de unos objetivos claros y de una racionalidad que considera el costo y el beneficio de su uso. Este artículo presenta un aná...

  8. El Esoterismo y la adivinación como fenómeno comunicativo en la televisión española

    Cid-Leal, Pilar; Recoder, Maria Josep; Cruz Palacios, Emilio

    2015-01-01

    En las parrillas nocturnas de los canales de Televisión Digital Terrestre (TDT) españoles abundan los programas de adivinación con consultas telefónicas. Pese a las transformaciones que ha experimentado el medio televisivo en los últimos años, estos programas, difícilmente clasificables dentro de los géneros televisivos clásicos, se mantienen. Porque son tanto un fenómeno comunicativo como un negocio para las televisiones, los consultorios privados de los vident...

  9. El fenómeno de la victimización en los centros penitenciarios de la Región de Murcia.

    Caravaca Sánchez, Francisco

    2013-01-01

    Hechos delictivos como los robos, amenazas, agresiones físicas y verbales e incluso sexuales se presentan como un hecho cotidiano en la vida penitenciaria, ligado al consumo de sustancias estupefacientes. 2. Hipótesis del estudio El propósito general de esta investigación consiste en conocer y evaluar los diferentes factores sociales y penitenciarios, que se encuentran ligados a la aparición y mantenimiento del fenómeno de la victimización en el ámbito penitenciario. Y posteriormente d...

  10. Aprendizaje espacial en laberintos en una tarea de discriminación. Los fenómenos de la inhibición latente y del aprendizaje perceptivo.

    Sansa i Aguilar, Joan

    1995-01-01

    [spa] La exposición previa a un estimulo que se usará como estímulo condicionado (EC) en un paradigma de condicionamiento clásico típicamente retrasa el condicionamiento posterior. Este es el fenómeno de la inhibición latente (IL) (Lubow, 1989). Sin embargo, en ocasiones esta exposición tiene el efecto opuesto. Así, en el aprendizaje latente, la exposición a un laberinto de múltiples unidades facilitará la elección del camino correcto cuando posteriormente se introduce e! reforzador (Tolman y...

  11. El fenómeno de la infoxicación visto desde la neurociencia : ¿Qué hay de nuevo?

    Orgaz Camacho, Alexandra

    2014-01-01

    El fenómeno de la infoxicación desde un punto de vista psicológico podemos definirlo como un estado percibido negativo, caracterizado por síntomas de estrés psicológico, alteración del proceso de toma de decisiones y en general pérdida de la capacidad de procesar y utilizar información de manera eficiente. A pesar de que el concepto como tal es de reciente uso, esta descripción de sintomatología ha sido ampliamente estudiada tanto desde la psicología como desde la neurociencia,...

  12. Algunas interpretaciones sobre el fenómeno de las estaciones en niños, estudiantes y adultos: revisión de la literatura

    Navarrete Salvador, Antonio; Azcárate Goded, María del Pilar; Oliva Martínez, José María

    2004-01-01

    En este trabajo se lleva a cabo un análisis de la literatura sobre las interpretaciones personales de los alumnos acerca del fenómeno de las estaciones. En primer lugar se describe el procedimiento y los criterios seguidos en la revisión y se analizan las características metodológicas de los estudios revisados. En segundo lugar se pasa a describir e interpretar los modelos explicativos más frecuentes que aparecen en la bibliografía, comentando la incidencia que la edad o la var...

  13. Transición en el cine juvenil japonés 1956-1960: del fenómeno taiyozoku a la nueva ola.

    Centeno Martín, Marcos Pablo

    2009-01-01

    El presente trabajo pretende abordar el tema de la constitución de la nueva ola japonesa, en una de sus primeras variantes temático-formales: la de “juventud y ruptura generacional” en el periodo de transición de 1956 a 1960. En estos años ocurren una serie de fenómenos cinematográficos y extra-cinematográficos que serán la causa de la ruptura con el periodo de los humanistas anterior, dando origen a un nuevo paradigma, la nueva ola o nuberu bagu japonesa. Un nuevo cine que a lo largo de las...

  14. Estudio del fenómeno Social Media en la pequeña empresa del sector TIC español

    Río Onrubia, María Rebeca del

    2014-01-01

    En un mundo en el que cada vez son más las personas que utilizan Internet para llevar a cabo sus comunicaciones y relaciones, tanto a nivel personal como profesional, las Redes Sociales se han convertido en una herramienta, para muchos imprescindible, de interacción social. A lo largo de este proyecto se realizará un análisis exhaustivo de las características del ya conocido como Fenómeno Social Media, para posteriormente centrar toda la atención en las ventajas y desventajas de dicha acti...

  15. El menemismo en la encrucijada : Perspectivas analíticas que lo abordan como fenómeno político

    Erbetta, María Cecilia

    2005-01-01

    La principal tarea que abordamos en este trabajo es la de recuperar las categorías analíticas que utilizaban los investigadores e intelectuales durante los noventa para pensar el menemismo como fenómeno político. Es por tal razón, que los trabajos reunidos aquí en su mayoría fueron escritos durante esta decáda, salvo contadas excepciones. Analíticamente los hemos separado en dos grandes grupos. En la Parte I de este trabajo encontraremos a un primer grupo de autores que han estudiado el menem...

  16. Bíodegradación de los compuestos fenólícos presentes en el alpechín

    Maestro Durán, R.; Borja Padilla, R.; Martín, Antonio; Fiestas Ros de Ursinos, J. A.; Alba Mendoza, J.

    1991-01-01

    Las aguas residuales de la obtención del aceite de oliva o alpechines son responsables de la mayor contaminación medioambiental de Andalucía por su elevada carga de materia orgánica. Su depuración por biometanización es difícil debido a la actividad antimicrobiana de los compuestos fenólícos. Este tipo de sustancias puede eliminarse en gran parte tratando previamente el alpechín por vía aerobia con microorganismos específicos, después de lo cual la depuración anaerobia ti...

  17. Relación entre compuestos fenólicos y calidad nutritiva en especies pratenses.

    Vázquez de Aldana, Beatriz R.; García Ciudad, A.; García Criado, B.

    2009-01-01

    [ESP]Los compuestos fenólicos comprenden un grupo de compuestos que a menudo influyen de forma negativa en la calidad del pasto. El objetivo de este trabajo fue determinar el contenido de fenoles totales en varias especies frecuentes en pastos de dehesa de la provincia Salamanca y establecer su relación con otros parámetros de la calidad nutritiva (fibra ácido detergente, fibra neutro detergente, celulosa, lignina, proteína y digestibilidad). Se encontraron correlaciones negativas signific...

  18. Estudo da estabilidade, comportamento reológico e dos compostos fenólicos de frutas da Mata Atlântica

    Karwowski, Marília Silva Malvezzi

    2013-01-01

    Resumo: Este estudo avaliou o comportamento reológico, a estabilidade física e os compostos fenólicos das frutas Uvaia (Eugenia uvalha) e Pitanga (Eugenia uniflora L.). O efeito da temperatura sobre o comportamento reológico das frutas foi analisado (10-60 °C) por meio de análise reológica não-oscilatória. As amostras integrais (purês) apresentaram comportamento pseudolástico (n< 1), enquanto que as amostras centrifugadas apresentaram comportamento Newtoniano (n = 1). A equação de Arrhenius d...

  19. Utilización de Uvas en la Elaboración de Mermeladas: Estudio de Estabilidad de Compuestos Fenólicos

    Olachea Arce, Angel

    2012-01-01

    Se recoge en la bibliografía consultada diversos trabajos dónde se ha comprobado la presencia de compuestos con actividad beneficiosa para la salud humana en los residuos y subproductos del cultivo de la uva y del proceso de vinificación, concretamente compuestos de tipo fenólicos, carbohidratos y restos proteicos. Los restos de la vinificación representan un volumen importante de residuos/subproductos en el entorno enológico. En concreto, según estadísticas y datos del 2011, en España se ...

  20. Nursing phenomena identified in family planning visits with ICNP - Beta Version 2 Fenómenos de enfermería identificados en consultas de planificación familiar según la ICNP, Versión Beta 2 Fenômenos de enfermagem identificados em consultas de planejamento familiar segundo a ICNP - Versão Beta 2

    Gislaine Eiko Kuahara Camiá

    2006-10-01

    Full Text Available This descriptive, exploratory, retrospective survey, carried out at a family planning service, aimed to identify nursing phenomena during nursing visits according to the ICNP, Beta version 2. Data were collected based on 52 records of nursing visits, realized from October 2001 to December 2002. To conduct the cross-mapping process, all identified nursing phenomena were joined, organized and compared according to the ICNP's terms. Of the 51 identified nursing phenomena/diagnoses, 46 (90.2% showed exact and partial concordance. The identified nursing phenomena can be used to assist nurses to provide care for clients in family planning services. The ICNP showed to be a comprehensive program, although some terms need to be reviewed and others enhanced. However, considering that it is an international classification applicable to several countries, the mapping process and cross-references were very satisfactory.Esta investigación descriptiva, exploratoria, retrospectiva se llevó a cabo en un servicio de planeo familiar. El objetivo fue identificar los fenómenos de enfermería en consultas según la ICNP, versión Beta 2. La recolección de datos se realizó en 52 historias clínicas, en consultas de enfermería durante el período de octubre del 2001 a diciembre del 2002. Para el mapeo cruzado, todos los fenómenos de enfermería identificados fueron compilados, organizados y comparados con los términos de la ICNP. De los 51 fenómenos/diagnósticos de enfermería identificados, 46 (90,2% presentaron concordancia exacta y parcial. Los fenómenos de enfermería identificados podrán ayudar los enfermeros para el cuidado de clientes que procuran servicios de planificación familiar. La ICNP demostró ser extenso, aunque algunos términos necesitan ser revisados y/o aumentados. Sin embargo, llevando en consideración que se trata de una clasificación internacional aplicable a diversos países, el mapeo y el cruce de sus datos fueron satisfactorios