Radon measurements in the cave houses of Crevillente (Spain)

This paper focuses on the cave houses of Crevillente (Spain) as a traditional housing experience which takes advantage of local environmental conditions through simple architectural proposals, paying particular attention to the presence of radon gas inside these underground constructions. Our aim is twofold: first, to analyse the architectural conditions of the different excavated typologies found in the municipality and second, to relate them to the existing radon gas levels after checking internal concentration by means of E-PERM® long-term devices placed inside the cave houses in 2011. The measurements corresponding to the main typologies in normal use conditions show that the highest values are 881.9 Bq/m3 in the cave typology, 484.1 Bq/m3 in the cave + attached constructions typology and 373.4 Bq/m3 in the cave + house typology, with geometric mean values of 572.1, 114.0 and 75.5 Bq/m3, respectively. It can be inferred from these results that cave house levels sometimes exceed those included in the 90/143/Euratom European Commission Recommendation on the protection of the public against indoor exposure to radon. The reason why cave houses are more susceptible to radon accumulation in their spaces lies in their direct and permanent contact with the ground where they are located.

Elogio del cuadrado: cuadrícula, cuadro, cuatro, cubo

Un recorrido por la producción de Le Corbusier evidencia la insistente presencia del cuadrado como base de las composiciones en diversos campos (urbanismo, arquitectura, pintura, mobiliario...) y en diferentes formatos (en planta, alzado y sección, o como marco, módulo y cuadrícula). La presente comunicación realiza un análisis formal (gráfico y simbólico) de sus proyectos y obras, rastreando los modos en que se utiliza el cuadrado permaneciendo en el tiempo como una constante recurrente. Para ello se recorren cuatro áreas temáticas que descienden en escala y en dimensiones: 1) capitolios, 2) museos, 3) pabellones y 4) casas, estudiando una serie de ejemplos en cada área a partir de los planos de la Fundación Le Corbusier, generando discursos que reconstruyen un hilo del tiempo en la evolución de los procesos compositivos. De este modo, se desgrana el empleo del cuadrado, en correspondencia con las áreas de estudio, como: 1º) perímetro de la plaza pública donde insertar las arquitecturas representativas, 2º) marco o caja-fuerte donde encerrar los tesoros artísticos (o sagrados), 3º) volumen cúbico abierto y desmontable y 4º) caja definida por la retícula de la estructura. El cuadrado es siempre un medio y no un fin. Persiste un intento de sugerir algunos de los orígenes en su formación clasicista, sus viajes y sus pinturas.

New theropod remains from the Tiourarén Formation (?Middle Jurassic, Niger) and their bearing on the dental evolution in basal tetanurans

A fragment of a maxilla and isolated theropod teeth from the (?) Middle Jurassic Tiourarén Formation are described. The specimens come from Tadibene, in the rural community of Aderbissinat, Thirozerine Department, Agadez Region, Niger. They were identified through direct comparison with teeth previously described in the literature as well as on the basis of discriminant and morphometric analyses. Our results suggest they belong to Ceratosauridae, Megalosauridae, and the oldest representatives of Spinosauridae. The analyzed sample shows some uncommon characters, such as spinosaurid-like ornamentation in megalosaurid-like teeth, or spinosaurid-like teeth with a low number of denticles, which sheds light on tooth morphology and dental evolution in basal tetanurans and early spinosaurids.