Fundamento geométrico y cinemático de la modelización teórica y experimental de deformaciones no-coaxiales

La combinación de dos componentes longitudinales en condiciones de no cambio de área, con un componente de cizalla paralelo a la dirección del componente de extensión, permite generar un espectro continuo de tipos de deformación entre la cizalla pura y la cizalla simple. El grado de no coaxialidad o la vorticidad se pueden definir por el ángulo que forman entre si las lineas de no rotación. La aplicación de sucesivos incrementos idénticos, mantiene constante la orientación de las lineas de no rotación. Sobre este principio se plantean dos vias de investigación en el campo de la génesis de estructuras de deformación dúctil en regimenes no coaxiales: la modelización analógicautilizandomateriaies artificiaies y la modelización matemática. Las propiedades de las lineas materiales de no rotación, son utilizadas vara diseñar una célula de deformación ex~erimental que cubra todo el espectro. Adicionalmente se presentan dos ejemplos de modelización teórica que muestran la influencia del grado de coaxialidad en la asimetria y orientación de pliegues.Combination of both longitudinal components with a shear component parallel to the direction of the longitudinal extension component leads to a continuum spectrum with pure and simple shear as end members. The degree of non coaxiality or the vorticity can be specified by means of the angle formed by lines undergoing no rotation. The application of successive identical strain increments, keeps uncbanged the orientation of the lines of no rotation after the first increment. On this basis two approaches are presented in order to enhance understanding of the formation of ductile structures under non coaxial strain regimes: experimental modelling using analogue materials and deformation stage, which should cover the whole spectrum between pure and simple shear. Additionally, by means of two examples of mathematical modelling it is shown how the non coaxiality controls fold asymmetry and orientation

Predicting reference points and associated uncertainty from life histories for risk and status assessment

To assess status of fish populations and the risks of overexploitation, management bodies compare fishing mortality rates and abundance estimates with reference points (RP). Generic, “data-poor” methods for estimating RP are garnering attention because they are faster and cheaper to implement than those based on extensive life history data. Yet data-poor RP are subject to many unquantified uncertainties. Here, we predict fishing mortality RP based on five levels of increasingly comprehensive data, to quantify effects of parameter and structural uncertainty on RP. Level I RP (least data) are estimated solely from species' maximum size and generic life history relationships, while level V RP (most data) are estimated from population-specific growth and maturity data. By estimating RP at all five data levels, for each of 12 North Sea populations, we demonstrate marked changes in the median RP values, and to a lesser extent uncertainty, when growth parameters come from data rather than life history relationships. As a simple rule, halving the median level I RP gives almost 90% probability that a level V median RP is not exceeded. RP and uncertainty were substantially affected by assumed gear selectivity; plausible changes in selectivity had a greater effect on RP than adding level V data. Calculations of RP using data for successive individual years from 1984 to 2014 showed that the median RP based on data for any given year would often fall outside the range of uncertainty for RP based on data from earlier or later years. This highlighted the benefits of frequent RP updates when suitable data are available. Our approach provides a quantitative method to inform risk-based management and decisions about acceptable targets for data collection and quality. Ultimately, however, the utility and extent of adoption of data-poor methods for estimating RP will depend on the risk aversion of managers

Precisiones acerca de la significación petrológica y estructural de las rocas gneísicas y cataclásticas del Maresme (prov. de Barcelona)

Se estudian pequeños afloramientos de rocas metamórficas y cataclásticas ubicadas en el granito herciniano de la Cadena Costera Catalana al NE de Barcelona. Tras una breve síntesis de las diversas ideas emitidas sobre la génesis de estas rocas se realiza un estudio comparativo de las mismas. De él se infiere la presencia de dos grupos de rocas de significación petrogenética y tectónica distinta: 1) Los gneises de Mataró, que resultan del metamorfismo polifásico progresivo herciniano de sedimentos del Paleozoico inferior y 2) las rocas cataelásticas de Caldetes, ligadas a deformaciones internas en el batolito del granito herciniano postectónico, acompañadas de transformaciones hidrotermales en mayor o menor grado.Small outcrops of metamorphic and cataclastic rocks, located in the Hercynian granite of the Catalan Litoral Ridge (NE from Barcelona) were studied. Following a brief examination of the previous ideas issued concerning the origin of these rocks, a comparative study has been made. As a result of the forementioned, the presence of two groups of rocks could be established, both having an individual petrogenetic and tectonic signification: 1) The Mataró Gneises outcome of a progressive and polyphasic metamorphism of Lower Paleozoic sedimentary rocks. 2) The Caldetes Cataclastic Rocks, are related to interna1 deformations within the hercynian late tectonic granite batholith, assisted in some extent by hydrothermalism

Combining Web 2.0 and Web Services in Collaborative Working Environments

Collaborative applications offer significant benefits in business sector. Usually, team members need to use several systems to carry out their tasks. What these users need is an environment which permits them to carry out these tasks automatically, considering the flow of information between the different systems and offering interoperability and composition features. Nowadays, Web Services have gained their prominence in providing these both features. On the other hand, the use of Web 2.0 allows to create web applications in which the user constitutes a key element. What we propose in this paper is the combination of both approaches for creating a Collaborative Working Environment (CWE)

Non-diffusive transport in plasma turbulence: a fractional diffusion approach

Numerical evidence of non-diffusive transport in three-dimensional, resistive pressure-gradient-driven plasma turbulence is presented. It is shown that the probability density function (pdf) of test particles' radial displacements is strongly non-Gaussian and exhibits algebraic decaying tails. To model these results we propose a macroscopic transport model for the pdf based on the use of fractional derivatives in space and time, that incorporate in a unified way space-time non-locality (non-Fickian transport), non-Gaussianity, and non-diffusive scaling. The fractional diffusion model reproduces the shape, and space-time scaling of the non-Gaussian pdf of turbulent transport calculations. The model also reproduces the observed super-diffusive scaling

First report of an olive ridley (Lepidochelys olivacea) inside the Mediterranean Sea

We report the first confirmed occurrence of a Lepidochelys olivacea in the Mediterranean Sea based on the study of an individual stranded on a beach, located in the town of Oropesa del Mar (40º05ʹ32ʺN, 0º08ʹ02ʺE), Castellón province, East Spain, in May 2014. Morphological and genetic analyses were used to confirm the identification of the species. The individual had a sequence that matched the 470 bp Lepidochelys olivacea haplotype F (Genbank accession number: AF051773), found in several Atlantic populations. This becomes one of the northernmost known occurrences of olive ridleys in the world and is the first reports of this species in the Mediterranean Sea