257 research outputs found

    L'enigma de Roca-Sentella

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    The Participation of Children and Adolescents in the Protection System: The Case of the Spanish Legislation

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    Children’s right to participation is enshrined in the Convention on the Rights of the Child (CRC), specifically in Article 12; however, the participation of children in the protection system continues to be a challenge. There is a need for a paradigm shift, in which children and adolescents (CA) are considered as active subjects of rights in all areas of their lives, and that means allowing them to participate in decisions that concern them. The study analysed 20 Spanish laws, both national and autonomous, that regulate child protection and the rights of CA in the protection system. It focuses on examining the participation of children in the protection system, divided into its three dimensions: the right to be informed, the right to be heard and the right to be involved. There is complexity in the different regulations. All of them are consistent with the CRC and provide for participation, but not all to the same extent. There is a lack of harmonisation between the legislation of autonomous communities, leading to practical difficulties for the professionals who have to implement the legislation on a daily basis.This research was funded by the coordinated research project I+D+i RTI2018-099305-B-C21 Un modelo de acción socioeducativa para la reunificación familiar en el sistema de protección a la infancia y la adolescencia desde el enfoque de la parentalidad positiva (A model of socio-educational action for family reunification in the child and adolescent protection system based on a positive parenting approach), granted by the Ministry of Science and Innovation of the Government of Spai

    Charge inhomogeneities due to smooth ripples in graphene sheets

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    We study the effect of the curved ripples observed in the free standing graphene samples on the electronic structure of the system. We model the ripples as smooth curved bumps and compute the Green's function of the Dirac fermions in the curved surface. Curved regions modify the Fermi velocity that becomes a function of the point on the graphene surface and induce energy dependent oscillations in the local density of states around the position of the bump. The corrections are estimated to be of a few percent of the flat density at the typical energies explored in local probes such as scanning tunnel microscopy that should be able to observe the predicted correlation of the morphology with the electronics. We discuss the connection of the present work with the recent observation of charge anisotropy in graphene and propose that it can be used as an experimental test of the curvature effects.Comment: 9 pages, 5 figures. v2: Abstract and discussion about experimental consequences expande

    Dirac fermions in a power-law-correlated random vector potential

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    We study localization properties of two-dimensional Dirac fermions subject to a power-law-correlated random vector potential describing, e.g., the effect of "ripples" in graphene. By using a variety of techniques (low-order perturbation theory, self-consistent Born approximation, replicas, and supersymmetry) we make a case for a possible complete localization of all the electronic states and compute the density of states.Comment: Latex, 4+ page

    Revisión actualizada de la estratigrafía y biota del Ediacárico y Terranóvico de los Montes de Alcudia-Toledo, Zona Centroibérica, España

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    An updated stratigraphic subdivision of the Ediacaran and Terreneuvian in the Alcudia valley and the Toledo Mountains, Central Iberian Zone, is documented here. The Lower Alcudian-Domo Extremeño Supergroup is subdivided, from bottom to top, into the conformable Guadiana (La Coronada and Sta. Mª de Zújar formations) and Campanario (Botija, Monroy and Orellana formations) groups. The supergroup contains biostratigraphically non-significant bacterial acritarchs and dubious fossils, but its Ediacaran age is constrained by detrital zircon analyses. This siliciclastic sedimentary package is unconformably overlain by either the siliciclastic-carbonate Ibor Group (Castañar, Villarta and Arrocampo formations) or the siliciclastic Cíjara Formation. The fossil content of the former group includes Sabelliditids, Vendotaenids, macrophytes, bioaccumulations and reefs rich in Cloudina, Sinotubulites, Protolagena and stromatolites and thrombolites, and a wide diversity of ichnofossils; whereas the Cíjara Formation has yielded bacteria attributed to Bavlinella and Palaeogomphosphaeria, and simple trace fossils (Gordia, Helminthoidichnites and treptichnids). The Ediacaran-Cambrian boundary, based on ichnofossils, lies at the base of the Arrocampo Formation and the uppermost part of the Cíjara Formation. In the Alcudia valley, the Ibor Group is subdivided into another three-fold, lithologically equivalent subdivision, known as the Tamujar, Hinojosas (rich in ichnofossils, such as treptichnids, Monomorphichnus, Psammichnites and Taphrelminthopsis) and Cabezarrubias (including Bergaueria and Planolites) formations. Another unconformity, intra-Fortunian in age, marks the tops of the Ibor Group and the Cíjara Formation, wich are subsequently overlain by the San Lorenzo Formation and some megabreccia beds, respectively. Overlying the slope-related Fuentes, Membrillar and Navalpino megrabreccia beds, the Terreneuvian-Cambrian Series 2, heterolithic Pusa Formation is subdivided into thre members, the middle one characterized by the record of phosphate ore deposits (e.g., the Fontanarejo Bed). The formation is shale dominated and has yielded the body-fossil Beltanelliformis and numerous ichnofossils (Monomorphicnus and Treptichnus; lower member), sponge spicules associated with thrombolites (middle member), and Scenella, trilobites, archaeocyaths and ichnofossils (Dactyloidites, Psammichnites, Rusophycus and Teichichnus; upper member). Where the megabreccia beds are absent, the Ibor Group is unconformably overlain by the San Lorenzo and Fuentepizarra formations, the latter containing phosphatic limestone interbeds rich in skeletonized microfossils, such as Anabarella, which represents the Fortunian-Cambrian Stage 2 boundary interval.Se presenta en este trabajo una revisión actualizada de la estratigrafía del Ediacárico-Terranóvico del valle de Alcudia y los montes de Toledo, Zona Centroibérica. Se subdivide el Supergrupo infrayacente ediacárico del Alcudiense Inferior-Domo Extremeño en los Grupos del Guadiana (Formaciones de La Coronada y Sta. Ma de Zújar) y de Campanario (Formaciones de Botija, Monroy y Orellana). El supergrupo contiene varios acritarcos sin utilidad bioestratigráfica, así como dubiofósiles, pero su edad se ha establecido claramente a partir de zircones detríticos. Este litosoma siliciclástico aparece recubierto mediante contacto disconforme con el Grupo mixto de Ibor (Formaciones de Castañar, Villarta y Arrocampo) o la Formación siliciclástica del Cíjara. El contenido fósil del Grupo de Ibor incluye sabellidítidos, vendoténidos, macrofitas, bioacumulaciones y arrecifes con Cloudina, Sinotubulites, Protolagena y estromatolitos y trombolitos, así como una amplia variedad de icnofósiles; la Formación del Cíjara ha librado microfósiles bacterianos como Bavlinella y Palaeogomphosphaeria, y pistas fósiles simples (Gordia, Helminthoidichnites y treptícnidos). El límite Ediacárico-Cámbrico, a partir de icnofósiles, se sitúa en la parte basal de la Formación de Arrocampo y en la parte terminal de la del Cíjara. El valle del Alcudia ofrece algunas peculiaridades, lo que se refleja por el mantenimiento de una subdivisión litoestratigráfica propia: el Grupo de Ibor se divide en las Formaciones de Tamujar, Hinojosas (caracterizada por su contenido en icnofósiles, que incluye treptícnidos, Monomorphichnus, Psammichnites y Taphrelminthopsis) y Cabezarrubias (con Bergaueria y Planolites). Otra discontinuidad mayor se reconoce a techo del Grupo de Ibor y de la Formación del Cíjara, recubiertos respectivamente por la Formación de San Lorenzo y unas capas de megabrechas muy características. Las megabrechas, interpretadas como depósitos de talud y conocidas como las capas de Fuentes, Membrillar y Navalpino, se sitúan a base de la Formación del Pusa, de composición heterolítica y de edad Terranóvico a Serie cámbrica 2. Se subdivide el Pusa en tres miembros, destacando el intermedio por el registro de yacimientos de interés económico de fosfato (Capa de Fontanarejo). La Formación del Pusa contiene el fósil de cuerpo blando Beltanelliformis así como numerosos icnofósiles (Monomorphicnus y Treptichnus; miembro inferior), espículas de esponja asociadas con trombolitos (miembro intermedio) y Scenella, trilobites, arqueociatos e icnofósiles (Dactyloidites, Psammichnites, Rusophycus y Teichichnus; miembro superior). En ausencia de megabrechas, el Grupo de Ibor aparece directamente recubierto por las Formaciones de San Lorenzo y Fuentepizarra, esta última caracterizada por su contenido en calizas fosfáticas ricas en microfósiles, como Anabarella, que caracterizan la transición Fortuniense-Piso Cámbrico 2

    Primera cita de Cloudina carinata Cortijo et al., 2010 en Sudamérica, Formación de Tamengo, Grupo de Corumbá, Brasil Brazil

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    It is herein presented the unprecedented occurrence of Cloudina carinata Cortijo et al., 2010 in the American continent. This new occurrence expanded the geographic distribution of this species, until now reported from sections in Spain and Siberia. The assembled biomineralizing metazoans Cloudina carinata, Cloudina lucianoi (Beurlen & Sommer, 1957) and Corumbella werneri Hahn et al., 1982 are presented for the first time from the Tamengo Formation, Corumbá Group, Porto Figueiras section, Corumbá Municipality, Mato Grosso do Sul State, Brazil. This new occurrence could be employed as an additional biostratigraphic tool for international correlation of the terminal Ediacaran, as well as for palaeobiogeographic and palaeoecologic reconstructions.Se documenta en este resumen la primera aparición de Cloudina carinata Cortijo et al., 2010 en el continente americano. Esta nueva aparición extiende la distribución geográfica de esta especie, hasta ahora restringida a España y Siberia. Se presenta por primera vez en la Formación de Tamengo (Corumbá, Estado de Mato Grosso do Sul, Brasil) la asociación de metazoos mineralizados compuesta por Cloudina carinata, Cloudina lucianoi (Beurlen & Sommer, 1957) y Corumbella werneri Hahn et al., 1982. Esta asociación podría ser útil como marcador bioestratigráfico en las correlaciones internacionales del Ediacárico terminal, así como para futuras reconstrucciones paleobiogeográficas y paleoecológicas

    Refusals of offers by catalan learners of english

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    This is an interlanguage pragmatics study dealing with refusals of offers by Catalan EFL subjects (ILC) compared to those made by British (NSE) taken from Aksoyalp (2009). The research questions are to know what strategies ILC use while performing refusals of offers and to determine if they achieve a native-like frequency. A DCT is used to gather the data which is coded following Beebe et al.'s (1990) classification. The main finding is confirming, as expected, that ILC do not have a native-like frequency and do not use the same strategies as NSE regardless of their C1 level.Estudi de la pragmàtica de l'interllenguatge basat en com rebutgen les ofertes en anglès els natius Catalans (ILC) comparats amb els anglesos (NSE) (dades obtingudes d'Aksoyalp, 2009). Les dades dels ILC s'obtenen amb un DCT i són codificades seguint la classificació de Beebe et al.(1990). Les hipòtesis són saber quines estratègies utilitzen els ILC i si aconsegueixen una freqüència d'us semblant als natius. La troballa principal és, com s'esperava, que no en tenen una freqüència d'us semblant a la dels natius i que tampoc utilitzen les mateixes estratègies que ells a pesar del seu alt nivell d'anglès (C1 o més)
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