808 research outputs found

    Hydrochemistry characterisation of protected marine ecosystems in Cadiz

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    Wetlands have a great natural wealth due to their borderline nature, representing the point where lithosphere, hydrosphere and atmosphere converge. The wetlands of Cadiz, at the southern extreme of Europe, also play an important role as a stopover area for migratory birds. This paper presents the results of a sampling project conducted during the spring of 1997 in the Guadiaro and Palmones Rivers, the Barbate estuary, Sancti Petri sound, and the San Pedro River salt marsh. For each system, three sampling stations were established along a salinity gradient, and these variables were measured: salinity, pH and chloride, sulphate, sodium, potassium, calcium, magnesium, nitrite, nitrate, silicate ammonia, organic carbon, dissolved oxygen, chlorophyll and phaeopigment concentrations. Several behaviours were found for the various systems: the Guadiaro and Palmones Rivers fit a fluvial estuary pattern, with low ionic concentrations and poor remineralisation. The San Pedro River and Sancti Petri sound are tidal systems with a typical seawater composition and high benthic regeneration. The Barbate estuary represents an intermediate scenario between the preceding ones, with a pronounced salinity gradient along its course.Los humedales tienen una gran riqueza natural debido a su carácter de franja donde convergen litosfera, hidrosfera y atmósfera. Los de la provincia de Cádiz, en el extremo meridional de Europa, tienen además una gran importancia como lugar de paso de las aves migratorias. En este trabajo se exponen los resultados obtenidos durante la primavera de 1997 en los estuarios de los ríos Guadiaro y Palmones, el estuario del Barbate, en las marismas del Caño de Sancti Petri y las del río San Pedro. Para cada uno de los sistemas se establecieron tres estaciones de muestreo a lo largo del gradiente de salinidad, y se determinó la salinidad, el pH y las concentraciones de cloruro, sulfato, sodio, potasio, calcio, magnesio, nitrito, nitrato, silicato, amonio, fosfato, carbono orgánico, oxígeno disuelto, clorofila a y feopigmentos. Se encontraron diferentes comportamientos para los distintos sistemas: el Guadiaro y el Palmones responden a un patrón de estuario de tipo fluvial, con concentraciones iónicas muy bajas y una escasa remineralización de la materia orgánica. El río San Pedro y el Caño de Sancti Petri son, por el contrario, sistemas mareales con aguas de comportamiento típicamente marino y una alta regeneración bentónica. El estuario del Barbate es una situación intermedia entre las anteriores y posee un marcado gradiente de salinidades a lo largo de su cauce.Instituto Español de Oceanografí

    Stability of liquid bridges between twisted elliptical disks

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    The influence in the stability of long liquid bridges supported between two elliptical-shaped disks of their main axis relative orientation is investigated. A numerical continuation method capable of finding equilibrium shapes, both stable and unstable, is used to calculate a series of equilibrium shapes supported by disks of increasing eccentricity for different relative orientation of the disks axis. The stable or unstable character of each of the shapes is calculated to determine the position of the stability limit and its characte

    Identificación de movimiento para enanas marrones en imágenes wise.

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    Las enanas marrones son objetos subestelares que hace aproximadamente 25 años fueron con firmadas y por esto poco se conoce de ellas, pues su mecanismo de formación hasta el d a de hoy es un misterio. Pero sabemos que comparten características similares a las estrellas y planetas.

    Working with the HL7 metamodel in a Model Driven Engineering context

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    HL7 (Health Level 7) International is an organization that defines health information standards. Most HL7 domain information models have been designed according to a proprietary graphic language whose domain models are based on the HL7 metamodel. Many researchers have considered using HL7 in the MDE (Model-Driven Engineering) context. A limitation has been identified: all MDE tools support UML (Unified Modeling Language), which is a standard model language, but most do not support the HL7 proprietary model language. We want to support software engineers without HL7 experience, thus realworld problems would be modeled by them by defining system requirements in UML that are compliant with HL7 domain models transparently. The objective of the present research is to connect HL7 with software analysis using a generic model-based approach. This paper introduces a first approach to an HL7 MDE solution that considers the MIF (Model Interchange Format) metamodel proposed by HL7 by making use of a plug-in developed in the EA (Enterprise Architect) tool.Ministerio de Ciencia e Innovación TIN2013-46928-C3-3-RInstituto de Salud Carlos III PI12/01571Instituto de Salud Carlos III PT13/0006/003

    Towards an eco-friendly coffee rust control : compilation of natural alternatives from a nutritional and antifungal perspective

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    Hemileia vastatrix (HV) is the pathogen responsible for the coffee leaf rust (CLR) disease that has spread globally. CLR causes losses of up to a billion dollars annually and affects all types of crops regardless of their production regime (organic or inorganic). Additionally, smallholders produce approximately 80% of coffee in developing countries. The condition causes losses of up to a billion dollars annually. It affects all types of crops regardless of their production regime (organic or inorganic). Approximately 80% of coffee is produced by smallholders in developing countries. Until the 90s, shaded-production systems and native varieties were encouraged; however, the rapid spread of CLR has forced farmers to migrate towards inorganic schemes, mainly due to a lack of knowledge about natural alternatives to pesticides that can be implemented to control HV. Therefore, the purpose of this article is to compile the currently existing options, emphasizing two key factors that guarantee efficient rust control: selective fungicidal activity against HV and the nutrition of coffee crops. Thus, by comprehending how these natural compounds (such as plant, bacteria, fungi, animals, or algae metabolites) impact coffee rust proliferation. Furthermore, since a various range of biochar effects contributes to the control of foliar fungal pathogens through modification of root exudates, soil properties, and nutrient availability, which influence the growth of antagonist microorganisms, we present a review of the pathogen-suppressive effects of biochar, and new control strategies suitable for organic schemes can be developed.Publisher PDFPeer reviewe

    Has cupper ion any effect on Sinorhizobium Melitoili bacteria?

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    Proceedings of the I Congress PIIISA celebrado en la Estación Experimental del Zaidín, Granada, el 26 de abril de 2012.Sinorhizobium meliloti is a soil bacterium that in symbiosis with Alfalfa leguminous plants fixes N2 to ammonia. This process occurs after an intimate communication between host and microsimbiont in the rhizosphere niche. This soil bacterium may suffer biotic and abiotic stresses in this complex environment. Resistance to any of this stresses can be an advantage for this type of bacteria. In this work we test the effects of Cupper ion in the bacterium Sinorhizobium meliloti. We found an effect on pigmentation and this effect is specific of each isolate (i.e. it is very pronounced for the isolate AK83 from Aral sea in Russia). On the other hand, comparison of Cupper ion resistance phenotype between isolates 1021 and GR4 suggests that the resistance of GR4 could be due to a set of 10 genes found in the cryptic plasmid pRmeGR4a of this strain. However, this resistance phenotype also appears in other isolates, and it could be explained by an alternative phenotype as Exopolysaccaride production (EPS+).It was supported mainly by research project MICINN Consolider‐Ingenio 2010. CSD2009‐00006; Scientific research by Young Students in Science (PIIISA2012; http://emc2astronomy.blogspot.com/).Peer reviewe

    Electrophoretic mobility of supercoiled, catenated and knotted DNA molecules.

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    We systematically varied conditions of two-dimensional (2D) agarose gel electrophoresis to optimize separation of DNA topoisomers that differ either by the extent of knotting, the extent of catenation or the extent of supercoiling. To this aim we compared electrophoretic behavior of three different families of DNA topoisomers: (i) supercoiled DNA molecules, where supercoiling covered the range extending from covalently closed relaxed up to naturally supercoiled DNA molecules; (ii) postreplicative catenanes with catenation number increasing from 1 to ∼15, where both catenated rings were nicked; (iii) knotted but nicked DNA molecules with a naturally arising spectrum of knots. For better comparison, we studied topoisomer families where each member had the same total molecular mass. For knotted and supercoiled molecules, we analyzed dimeric plasmids whereas catenanes were composed of monomeric forms of the same plasmid. We observed that catenated, knotted and supercoiled families of topoisomers showed different reactions to changes of agarose concentration and voltage during electrophoresis. These differences permitted us to optimize conditions for their separation and shed light on physical characteristics of these different types of DNA topoisomers during electrophoresis
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