Gauge transformations for higher-order lagrangians

Noether's symmetry transformations for higher-order lagrangians are studied. A characterization of these transformations is presented, which is useful to find gauge transformations for higher-order singular lagrangians. The case of second-order lagrangians is studied in detail. Some examples that illustrate our results are given; in particular, for the lagrangian of a relativistic particle with curvature, lagrangian gauge transformations are obtained, though there are no hamiltonian gauge generators for them.Comment: 22 pages, LaTe

Configuration of geological domains and geodynamic evolution of the Africa-Eurasia plate boundary off SW Iberia revisited based on seismic velocity and density models

European Geosciences Union General Assembly 2015 (EGU2015), 12-17 April 2015, Vienna, Austria.-- 1 pageWe present a new classification of geological (basement) domains at the Africa-Eurasia plate boundary offshore SW Iberia, together with a regional geodynamic reconstruction spanning from the Mesozoic extension to the Neogene-to-present-day convergence. It is based on seismic velocity and density models along two regional wide- angle seismic transects, one running NW-SE from the Tagus to the Seine abyssal plains, and the other running N-S from S Portugal to the Seine Abyssal Plain, combined with previously available information. The seismic velocity and density structure at the Seine Abyssal Plain and the internal Gulf of Cadiz indicates the presence of a highly heterogeneous oceanic crust, similar to that described in ultra-slow spreading centers, whereas in the Horseshoe and Tagus abyssal plains, the basement structure resembles that of exhumed mantle sections identified in the Northern Atlantic margin. The integration of all this new information allows defining the presence of three oceanic domains off SW Iberia: (1) the Seine Abyssal Plain domain, generated during the first stages of slow seafloor spreading in the NE segment of the Central Atlantic (Early Jurassic); (2) the Gulf of Cadiz domain, made of oceanic crust generated in the Alpine-Tethys spreading system between Iberia and Africa, which was coeval with the formation of the Seine Abyssal Plain domain and lasted up to the North Atlantic continental break-up (Late Jurassic); and (3) the Gorringe Bank domain, mainly made of rocks exhumed from the mantle with little synchronous magmatism, which formed during the first stages of North Atlantic opening (Early Cretaceous). Our models suggest that the Seine Abyssal Plain and Gulf of Cadiz domains are separated by the Lineament South strike-slip fault, whereas the Gulf of Cadiz and Gorringe Bank domains appear to be limited by a deep thrust fault located at the center of the Horseshoe Abyssal Plain, which coincides with the seismicity cluster nucleated in the middle of the plain that shows moment tensor solutions of reverse faulting at depths of 40–60 km. The formation and evolution of these three domains during the Mesozoic is key to understand the sequence of events that occurred during the first stages of opening of the Northern Atlantic and its connection and interplay with the Western Mediterranean basinPeer Reviewe

Casos de malaltia per Virus Chikungunya, Dengue i Zika a Catalunya: informe 2018

Virus Chikungunya; Dengue; ZinkaChikungunya virus; Dengue; ZinkaVirus Chikungunya; Dengue; ZinkaDocument que ofereix el resum dels casos de malaltia per Virus Chikungunya, Dengue i Zika a Catalunya durant un període de l'any 2018

Processing and interpretation of multichannel seismic reflection data ( SWIN-06 cruise): from the horsehoe to seine abyssal plains (Gulf of Cadiz)

Martech 2007 International Workshop on Marine Technology, 15-16 november 2007, Vilanova i la Geltrú, Spain.-- 2 pages, 1 figureThe authors acknowledge the support of the SWIM project (REN2002-11234- E-MAR), National project EVENT (CGL 2006-12861-C02-02) and the EU-NEAREST project (Ref. 037110)Peer reviewe

Autoevaluación y Toma de Decisiones para Mejorar la Competencia Oral en Educación Secundaria

La incorporación en los centros educativos de las Tecnologías de la Información y la Comunicación (TIC) supone una gran oportunidad para la formación de los docentes, así como para el desarrollo de competencias por parte del alumnado. En la presente investigación se utiliza un Sistema Inteligente de Asistencia Pedagógica (SIAP) diseñado para formar al docente, ayudándole a diseñar sus clases, autoevaluando el progreso respecto a distintos hitos para lograr clases más participativas que fomenten la competencia oral del alumnado. El SIAP fue utilizado durante diez semanas en un diseño experimental con grupo control: 188 estudiantes de Educación Secundaria, 84 grupo intervención y 104 grupo comparación. Los indicadores que incluye mostraron cómo, a medida que se lograban los hitos docentes, mejoraba la competencia oral del alumnado. Complementariamente, en un cuestionario se observó un cambio positivo en el grupo de intervención en el autoconcepto del alumnado sobre distintas habilidades comunicativas

Characterizing active faults and associated mass transport deposits in the South Iberian Margin (Alboran Sean and Gulf of Cadiz): on-fault and off-fault paleoseismic evidence

During the last years we have carried out successive high-resolution marine geological and geophysical surveys to investigate the seismic potential of the slow-moving seismogenic faults from the South Iberian Margin. Based on ,ultiscale acoustic mapping, sub-seafloor seismic imaging and dating methods we have characterized submarine fault systems with unprecedented resolution. We present primary paleoseismic evidence obtained by direct investigations of selected faults from theMediterranean Sea (i.e. Carboneras Fault, Bajo Segura Fault, Adra Fault) and the external part of the Gulf of Cadiz (i.e. Marques de Pombal Fault, Horseshoe Fault, Coral Patch Ridge Fault and SWIM lineaments). The obtained fault seismic parameters suggest that these faults are active and capable of generating large magnitude (Mw > 6) seismic events, representing an earthquake and tsunami hazard for the surrounding coastal areas. Secondary paleoseismic evidence in the SW Iberian Margin (based on landslides and turbidite deposits) yields a regional recurrence rate of large magnitude earthquake of 1800 - 2000 years