Wave energy and the upper depth limit distribution of Posidonia oceanica

Abstract It is widely accepted that light availability sets the lower limit of seagrass bathymetric distribution, while the upper limit depends on the level of disturbance by currents and waves. The establishment of light requirements for seagrass growth has been a major focus of research in marine ecology, and different quantitative models provide predictions for seagrass lower depth limits. In contrast, the influence of energy levels on the establishment, growth, and maintenance of seagrasses has received less attention, and to date there are no quantitative models predicting the evolution of seagrasses as a function of hydrodynamics at a large scale level. Hence, it is not possible to predict either the upper depth limit of the distribution of seagrasses or the effects that different energy regimes will have on these limits. The aim of this work is to provide a comprehensible methodology for obtaining quantitative knowledge and predictive capacity for estimating the upper depth limit of seagrasses as a response to wave energy dissipated on the seafloor. The methodology has been applied using wave data from 1958 to 2001 in order to obtain the mean wave climate in deep water seaward from an open sandy beach in the Balearic Islands, western Mediterranean Sea where the seagrass Posidonia oceanica forms an extensive meadow. Mean wave conditions were propagated to the shore using a two-dimensional parabolic model over the detailed bathymetry. The resulting hydrodynamics were correlated with bottom type and the distribution of P. oceanica. Results showed a predicted near-bottom orbital velocity of between 38 and 42 cm s -1 as a determinant of the upper depth limit of P. oceanica. This work shows the importance of interdisciplinary effort in ecological modeling and, in particular, the need for hydrodynamical studies to elucidate the distribution of seagrasses in shallow depths. Moreover, the use of predictive models would permit evaluation of the effects of coastal activities (construction of ports, artificial reefs, beach nutrientinput, dredging) on benthic ecosystems

Using Cross-Section Data to Adjust Technical Efficiency Indexes Estimated With Panel Data

This article proposes a procedure to incorporate cross-sectional information in the estimation of technical efficiency indexes obtained from panel data. A conventional index of technical efficiency is estimated in a first stage using panel data on inputs and outputs. The individual effects from the first stage are then adjusted using cross-sectional information, obtaining a corrected technical efficiency index. The model is applied to a panel of eighty-two Spanish dairy farms, where only cross-sectional information about input quality is available. An analysis of variance is performed between some variables and both the corrected and the uncorrected indexes, finding that the conclusions derived from the two analyses are different. Copyright 1999, Oxford University Press.

Competencia digital y literacidad: nuevos formatos narrativos en el videojuego «Dragon Age: Orígenes» Digital Competence and Literacy: Developing New Narrative Formats. The «Dragon Age: Origins» Videogame

Este artículo tiene como ejes conceptuales la competencia digital, la literacidad y los nuevos formatos narrativos. El aprendizaje permanente incluye las mismas como claves de la formación de la persona y sobre todo, como elemento que va a contribuir a su inserción en una sociedad dinámica y cambiante. Tras analizar dichas dimensiones, las mismas serán reflejadas en el videojuego denominado «Dragon Age: Orígenes», galardonado con el premio juego de rol del año en el año 2009. El desarrollo de la competencia digital conlleva una nueva alfabetización y en la misma es preciso hallar recursos motivadores para que dicha adquisición sea a la vez una cuestión lúdica y formativa. Otro aspecto relevante que será tratado en el texto tiene que ver con la multimodalidad textual (Kress &amp; Van Leeuwen, 2001), sobre todo con los nuevos formatos narrativos. Este hecho supone un importante avance social ya que las formas de lectura varían apareciendo formas distintas más motivadoras para el usuario pero no por ello poseen menor calidad. Éste es el caso de «Dragon Age: Orígenes», un juego de rol basado en la fantasía heroica ubicado en un mundo novedoso. Dicho juego se convierte en una excelente historia para ser leída y experimentada.<br>The approach of this article is centered on the concepts of digital competence and new narrative formats. We aim to apply these dimensions to the videogame «Dragon Age Origins», winner of the 2009 videogame of the year award. Its features - plot, characters and interactivity – make it ideal reading material in other formats and are highly motivational for young people. The development of digital competence signifies new literacy, and it is necessary to find new stimulating resources that combine the fun and formative dimensions. Equally relevant are multimodal texts (Kress &amp; Van Leeuwen, 2001), especially new narrative formats that imply social progress, as the ways of reading are different. The texts have acquired new formats with the same quality as books but they sometimes motivate users more. This is the case of «Dragon Age Origins», a dark heroic fantasy role-playing game set in a unique world containing a story to be read and experienced. Our analysis of the videogame discusses whether it should be considered a form of reading or not

Measurement of charged particle spectra in minimum-bias events from proton-proton collisions at root s =13 TeV

Pseudorapidity, transverse momentum, and multiplicity distributions are measured in the pseudorapidity range vertical bar eta vertical bar 0.5 GeV in proton-proton collisions at a center-of-mass energy of root s = 13 TeV. Measurements are presented in three different event categories. The most inclusive of the categories corresponds to an inelastic pp data set, while the other two categories are exclusive subsets of the inelastic sample that are either enhanced or depleted in single diffractive dissociation events. The measurements are compared to predictions from Monte Carlo event generators used to describe high-energy hadronic interactions in collider and cosmic-ray physics.Peer reviewe