Graphene and the Zermelo Optical Metric of the BTZ Black Hole

It is well known that the low energy electron excitations of the curved graphene sheet $\Sigma$ are solutions of the massless Dirac equation on a 2+1 dimensional ultra-static metric on ${\Bbb R} \times \Sigma$. An externally applied electric field on the graphene sheet induces a gauge potential which could be mimicked by considering a stationary optical metric of the Zermelo form, which is conformal to the BTZ black hole when the sheet has a constant negative curvature. The Randers form of the metric can model a magnetic field, which is related by a boost to an electric one in the Zermelo frame. We also show that there is fundamental geometric obstacle to obtaining a model that extends all the way to the black hole horizon.Comment: 10 pages Latex, no figures, substantial revisions, relation between magnetic and electric fields and Randers and Zermelo forms clarifie

Bangladesh: A Quantitative Review of Household Strategies in a Time of High Food Price Volatility for the Ensuring food and nutrition security in a time of volatility project

DFI

Electronic properties of curved graphene sheets

A model is proposed to study the electronic structure of slightly curved graphene sheets with an arbitrary number of pentagon-heptagon pairs and Stone-Wales defects based on a cosmological analogy. The disorder induced by curvature produces characteristic patterns in the local density of states that can be observed in scanning tunnel and transmission electron microscopy.Comment: Corrected versio

Experimental and full–scale pilot plant constructed wetlands for municipal wastewaters treatment

p. 43-52El (HMAE®) fue desarrollado originalmente en Bélgica mediante la aplicación de los valores ecológicos en las plantas hidrófilas inundadas y contaminadas. El sistema consistía en un estanque de estabilización (etapa I) seguido de un ecosistema semi-acuático plantado con helófitos (fase II) y por un ecosistema terrestre (fase III) donde se plantan especies leñosas. Un área de tratamiento neto del sistema experimental HMAE® de 9.4m2 por un habitante equivalente (ei) mostró un alto rendimiento promedio de los SS (66,5%); DQO (89%); DBO5 (87,5%) y bacterias fecales (99,997%). La disminución de la área de tratamiento de 2.8m2 / e.i. mostró un alto rendimiento promedio de SS (75%); DQO (80%); DBO5 (82%) y bacterias fecales (99,9%). Un sistema HMAE® fue construido en Bustillo de Cea (León, al noroeste de España) y se estudió su eficiencia de remoción. La materia orgánica, nutrientes y bacterias fecales se analizaron quincenal. Todo el sistema demostró eficiencias de remoción en la puesta en marcha tan alta como 98% de sólidos, 95% de DBO5 y hasta 99,99% para las bacterias fecalesS

La reputación regional como el diferencial de precio : estimación de un modelo hedónico de precios para los vinos de Castilla-La Mancha

Wine is a multi-attribute product and one of great differentiation. Consumers do not know wines’ intrinsic properties before its purchase; consumers need and look for extrinsic signals that allow them to infer those intrinsic properties. To evaluate those intrinsic wine properties, the article uses price as an extrinsic signal to express their value. The price used is a comparison between the prices suggested by the specialized guides and the ones proposed directly to the consumer at the on-line stores. With the hedonic price methodology, which relates price and attributes, the article shows the convergence between the value referenced (price) by the Spanish experts and the one paid (price) in the Spanish market, the former being independent of the interests of the economic agents and the latter not. Regional reputation is the only attribute that positively impacts the price of Castilian wine and is prioritized in the ranking of attributes.El vino es un producto de atributos múltiples y de gran diferenciación. Los consumidores no conocen las propiedades intrínsecas de los vinos antes de su compra; los consumidores necesitan y buscan señales extrínsecas que les permitan inferir esas propiedades intrínsecas. Para evaluar esas propiedades intrínsecas del vino, este artículo usa el precio como una señal extrínseca para expresar su valor. El precio utilizado es una comparación entre los precios sugeridos por las guías especializadas y los que se proponen directamente al consumidor en las tiendas en línea. Con la metodología de precios hedónicos, que relaciona precios y atributos, este artículo muestra la convergencia entre el valor referenciado (precio) por los expertos españoles y el valor pagado (precio) en el mercado español, siendo el primero independiente de los intereses de los agentes económicos y el último no. La reputación regional es el único atributo que impacta positivamente en el precio del vino castellano y se prioriza en el ranking de atributos al momento de compra.Fil: Castillo-Valero, Sebastián. Universidad de Castilla-La ManchaFil: Villanueva, Emiliano C.. Eastern Connecticut State UniversityFil: García-Cortijo, M. Carmen. Universidad de Castilla-La Manch

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

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

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

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

La reputación regional como el diferencial de precio: estimación de un modelo hedónico de precios para los vinos de Castilla-La Mancha

Wine is a multi-attribute product and one of great differentiation. Consumers do not know wines’ intrinsic properties before its purchase; consumers need and look for extrinsic signals that allow them to infer those intrinsic properties. To evaluate those intrinsic wine properties, the article uses price as an extrinsic signal to express their value. The price used is a comparison between the prices suggested by the specialized guides and the ones proposed directly to the consumer at the on-line stores. With the hedonic price methodology, which relates price and attributes, the article shows the convergence between the value referenced (price) by the Spanish experts and the one paid (price) in the Spanish market, the former being independent of the interests of the economic agents and the latter not. Regional reputation is the only attribute that positively impacts the price of Castilian wine and is prioritized in the ranking of attributes.El vino es un producto de atributos múltiples y de gran diferenciación. Los consumidores no conocen las propiedades intrínsecas de los vinos antes de su compra; los consumidores necesitan y buscan señales extrínsecas que les permitan inferir esas propiedades intrínsecas. Para evaluar esas propiedades intrínsecas del vino, este artículo usa el precio como una señal extrínseca para expresar su valor. El precio utilizado es una comparación entre los precios sugeridos por las guías especializadas y los que se proponen directamente al consumidor en las tiendas en línea. Con la metodología de precios hedónicos, que relaciona precios y atributos, este artículo muestra la convergencia entre el valor referenciado (precio) por los expertos españoles y el valor pagado (precio) en el mercado español, siendo el primero independiente de los intereses de los agentes económicos y el último no. La reputación regional es el único atributo que impacta positivamente en el precio del vino castellano y se prioriza en el ranking de atributos al momento de compra

Predicting grower choices in a regulated environment

The analysis of farmers’ decision making process in the framework of agricultural policy is particularly complex as they take action within a structure of interacting opportunities, preferences, benefits and social factors which ultimately account for their behavior. This paper will study viticulturists’ behaviour vis-à-vis this scenario. Their decisions in the face of different possible alternatives are analysed using a multinomial logit model and a sample of 74,502 plots in Castilla-La Mancha (Spain). The conclusion is that viticulturists from this region are more prone to maintaining the status quo in their plots due to the current public support security issues, uncertain scenarios and their natural risk aversion