28 research outputs found
Virtual reality applied to a full simulator of electrical sub-stations
This paper presents an application designed to train electrical sub-station operators by means of a virtual reality environment. The application allows full viewing of any of the sub-stations in the power supply network. With the appropriate hardware (HMD, 3D mouse and tracking systems) it is possible to navigate into the virtual world and interact with the elements. Each of the sub-station components has been reproduced in the simulation model, including the behavior laws associated with it, so the complete functionality of the sub-station can be simulated. This module is built into a larger and more complex computer system composed of the actual sub-station control system, the Geographical Information System which defines the topology of the network, and the functional system which simulates the electrical behavior of the sub-station. The application automatically updates in the virtual environment any changes to the sub-station's design and allows access, from this environment, to information on every component. The virtual reality application has been implemented in a hardware configuration and has the same interface as that used in the control system of the real sub-station. In this way, the system developed can be integrated into a replica of the complete power supply network control system emulating a real sub-station, it being able to fully interact with the global system, and allow totally real situations to be simulated
Tracking a mass mortality outbreak of pen shell Pinna nobilis populations: A collaborative effort of scientists and citizens
A mass mortality event is devastating the populations of the endemic bivalve Pinna nobilis in the Mediterranean Sea from early autumn 2016. A newly described Haplosporidian endoparasite (Haplosporidium pinnae) is the most probable cause of this ecological catastrophe placing one of the largest bivalves of the world on the brink of extinction. As a pivotal step towards Pinna nobilis conservation, this contribution combines scientists and citizens' data to address the fast- and vast-dispersion and prevalence outbreaks of the pathogen. Therefore, the potential role of currents on parasite expansion was addressed by means of drift simulations of virtual particles in a high-resolution regional currents model. A generalized additive model was implemented to test if environmental factors could modulate the infection of Pinna nobilis populations. The results strongly suggest that the parasite has probably dispersed regionally by surface currents, and that the disease expression seems to be closely related to temperatures above 13.5 degrees C and to a salinity range between 36.5-39.7 psu. The most likely spread of the disease along the Mediterranean basin associated with scattered survival spots and very few survivors (potentially resistant individuals), point to a challenging scenario for conservation of the emblematic Pinna nobilis, which will require fast and strategic management measures and should make use of the essential role citizen science projects can play
Terms of reference for the mediterranean tuna habitat observatory initiative
[EN] We present the Terms of Reference for a case study on a Mediterranean eco-region focusing on the environmental component of the Ecosystem Report Card. The objective of this case study is to describe and monitor the variability of environmental processes in the Mediterranean Sea that affect the ecology of large pelagic fishes, with a particular attention on tunas, and the possible role of climate change on this variability. Here we define the objectives and activities of the initiative, the participant roles, primary indicators and the methodological approach[FR] Ce document présente les termes de référence d’une étude de cas sur une écorégion méditerranéenne consacrée à la composante environnementale de la fiche informative sur les écosystèmes. L'objectif de cette étude de cas est de décrire et de suivre la variabilité des processus environnementaux en mer Méditerranée qui affectent l'écologie des grands poissons pélagiques, en accordant une attention particulière aux thonidés, et de déterminer le rôle possible du changement climatique sur cette variabilité. Nous définissons ici les objectifs et les activités de l'initiative, les rôles des participants, les indicateurs primaires et l'approche méthodologique.[ES] En el documento se presentan los términos de referencia para un estudio de caso sobre una ecorregión mediterránea centrado en el componente medioambiental de la ficha informativa sobre ecosistemas. El objetivo de este estudio de caso es describir y hacer un seguimiento de la variabilidad de los procesos medioambientales en el mar Mediterráneo que afectan a la ecología de los grandes peces pelágicos, con especial atención a los túnidos, y el posible papel del cambio climático en esta variabilidad. A continuación, se definen los objetivos y actividades de la iniciativa, las funciones de los participantes, los indicadores principales y el enfoque metodológico.Peer reviewe
Human Stressors Are Driving Coastal Benthic Long-Lived Sessile Fan Mussel Pinna nobilis Population Structure More than Environmental Stressors.
Coastal degradation and habitat disruption are severely compromising sessile marine species. The fan shell Pinna nobilis is an endemic, vulnerable species and the largest bivalve in the Mediterranean basin. In spite of species legal protection, fan shell populations are declining. Models analyzed the contributions of environmental (mean depth, wave height, maximum wave height, period of waves with high energy and mean direction of wave source) versus human-derived stressors (anchoring, protection status, sewage effluents, fishing activity and diving) as explanatory variables depicting Pinna nobilis populations at a mesoscale level. Human stressors were explaining most of the variability in density spatial distribution of fan shell, significantly disturbing benthic communities. Habitat protection affected P. nobilis structure and physical aggression by anchoring reveals a high impact on densities. Environmental variables instead played a secondary role, indicating that global change processes are not so relevant in coastal benthic communities as human-derived impacts.Versión del editor4,411
Genetic and oceanographic tools reveal high population connectivity and diversity in the endangered pen shell Pinna nobilis
For marine meta-populations with source-sink dynamics knowledge about genetic connectivity is important to conserve biodiversity and design marine protected areas (MPAs). We evaluate connectivity of a Mediterranean sessile species, Pinna nobilis. To address a large geographical scale, partial sequences of cytochrome oxidase I (COI, 590 bp) were used to evaluate phylogeographical patterns in the Western Mediterranean, and in the whole basin using overlapping sequences from the literature (243 bp). Additionally, we combined (1) larval trajectories based on oceanographic currents and early life-history traits and (2) 10 highly polymorphic microsatellite loci collected in the Western Mediterranean. COI results provided evidence for high diversity and low inter-population differentiation. Microsatellite genotypes showed increasing genetic differentiation with oceanographic transport time (isolation by oceanographic distance (IBD) set by marine currents). Genetic differentiation was detected between Banyuls and Murcia and between Murcia and Mallorca. However, no genetic break was detected between the Balearic populations and the mainland. Migration rates together with numerical Lagrangian simulations showed that (i) the Ebro Delta is a larval source for the Balearic populations (ii) Alicante is a sink population, accumulating allelic diversity from nearby populations. The inferred connectivity can be applied in the development of MPA networks in the Western Mediterranean.Spanish Ministry of Economy and Competitiveness [CTM2009-07013]; Ramon y Cajal Fellowship [RYC2014-14970]; Conselleria d'Innovacio, Recerca i Turisme of the Balearic Government; Spanish Ministry of Economy, Industry and Competitiveness IFCT [IF/00998/2014]; FCT [SFRH/BPD/63703/2009, SFRH/BPD/107878/2015, EXCL/AAG-GLO/0661/2012]; National Science Foundation [OCE-1419450]; Albert II of Monaco Foundationinfo:eu-repo/semantics/publishedVersio
The Argentine Competition Law and its Enforcement
This article analyzes the basic characteristics of the Argentine competition law and the way in which it has been enforced in several important antitrust cases. We begin with a section that introduces the evolution of the law, followed by another section about the basic economic and legal principles underlying that law. The rest of the article describes the enforcement of the law, in a number of cases that involve collusive practices, exclusionary practices, vertical restraints, abuses of dominant position, and mergers
Performance of circle hooks in a Mixed-species recreational fishery
The effects of the circle-hook on hooking injury, fish size and catch rates were evaluated for mixed-species recreational boat fisheries in the Balearic Islands (NW Mediterranean). The relationships between deep-hooking incidence (the main cause of fish mortality) and hook type (circle hooks vs conventional J-hooks), fish size, and angler were tested. Results demonstrated that the size of the fish was the most important predictor of deep-hooking incidence, as a larger fish size resulted in an increase in deeper wounds. Hook type also had a significant effect on the deep-hooking rate. Specifically, the deep-hooking rate of the most frequently-caught species, Diplodus annularis (L.) and Coris julis (L.), was reduced by greater than half with the circle hooks. The mean size of the fish caught and the unhooking time were not affected by the use of circle hooks. Finally, their use resulted in no change in the catch per unit effort (CPUE) compared to conventional hooks for both univariate and multivariate procedures. Hence, circle hooks are a promising conservation tool for marine resources when linked with catch-and-release strategies. © 2009 Blackwell Verlag, Berlin.Peer Reviewe
Efeito da concentração de coagulantes e do pH da solução na turbidez da água, em recirculação, utilizada no processamento dos frutos do cafeeiro
Com o objetivo de determinar a dose e a faixa de pH dos coagulantes sulfato de alumínio (SA), sulfato ferroso clorado (SFC), cloreto férrico (CF) e extrato de semente de moringa (ESM), que proporcionassem maior eficiência na remoção da turbidez na água residuária da despolpa de frutos do cafeeiro (ARDC), após serem efetuadas cinco recirculações, foram conduzidos ensaios de coagulação/floculação utilizando o aparelho "Jar-test". Todos esses coagulantes foram avaliados nas concentrações de 0; 0,5; 1,0; 1,5; 2,0; 2,5 e 3,0 g L-1. No caso da solução preparada com ESM, as doses utilizadas foram: 0; 10; 20; 30; 40; 50 e 60 mL L-1. O pH da solução em teste foi alterado, utilizando-se do hidróxido de sódio (NaOH), na concentração de 0,3 mol L-1, sendo avaliadas as faixas de 4,0 a 5,0; 5,0 a 6,0; 6,0 a 7,0 e 7,0 a 8,0. No ensaio de coagulação/floculação, o ESM proporcionou maior remoção de SS (sólidos em suspensão) da ARDC com a dose de 10 mL L-1 e pH de 4,27 (natural). Para os coagulantes SA e CF, os melhores resultados foram obtidos com a concentração de 3 g L-1 e pH de 7,27 e, para o coagulante SFC, com a concentração de 3 g L-1 e pH de 4,27