Alzamiento de la Iglesia-Cementerio de San Pedro y San Pablo en la Isla de Nueva Tabarca

El objeto de la presente comunicación es mostrar los trabajos del levantamiento de la Iglesia de San Pedro y San Pablo en la Isla de Nueva Tabarca, iniciados en 1998 y todavía no concluidos. Sin duda, una labor de relevante importancia debido al estado aparente de avanzado deterioro del inmueble. Para redactar el proyecto de restauración fue necesario un levantamiento preciso y minucioso ya que prácticamente no se disponía de ninguna documentación gráfica, los documentos gráficos localizados sólo ofrecían pistas, pero no daban una base documental suficiente como para acometer los trabajos de restauración. En la presente comunicación se describen: el proceso de toma de datos, levantamiento de la iglesia y la casa parroquial; los descubrimientos aportados por el levantamiento gráfico; así como las aportaciones realizadas al proyecto y a la construcción gracias al mismo.

Efecto del vertido de aguas residuales en el poblamiento de poliquetos en San Pedro del Pinatar

Los vertidos de aguas residuales son una de las principales fuentes de contaminación del medio marino. El objetivo principal de este estudio es determinar el grado de afección del vertido sobre el poblamiento de poliquetos asociado a fondos blandos. Las estaciones fueron distribuidas en dos transectos, uno de los cuales incluye la zona de influencia del vertido, y otro control a 4 km al sur. Se detectó una segregación del poblamiento de poliquetos en dos grandes grupos. Uno, caracterizado por una mayor proporción de fangos y materia orgánica; dominado por las familias Paraonidae, Lumbrineridae y Cirratulidae. El otro grupo, dominado por la familia Syllidae, se caracteriza por una gran heterogeneidad de los sedimentos Se observa una alta correlación entre los factores ambientales y la estructura del poblamiento de poliquetos.

Rotenone induces degeneration of photoreceptors and impairs the dopaminergic system in the rat retina

Rotenone is a widely used pesticide and a potent inhibitor of mitochondrial complex I (NADH-quinone reductase) that elicits the degeneration of dopaminergic neurons and thereby the appearance of a parkinsonian syndrome. Here we have addressed the alterations induced by rotenone at the functional, morphological and molecular levels in the retina, including those involving both dopaminergic and non-dopaminergic retinal neurons. Rotenone-treated rats showed abnormalities in equilibrium, postural instability and involuntary movements. In their outer retina we observed a loss of photoreceptors, and a reduced synaptic connectivity between those remaining and their postsynaptic neurons. A dramatic loss of mitochondria was observed in the inner segments, as well as in the axon terminals of photoreceptors. In the inner retina we observed a decrease in the expression of dopaminergic cell molecular markers, including loss of tyrosine hydroxylase immunoreactivity, associated with a reduction of the dopaminergic plexus and cell bodies. An increase in immunoreactivity of AII amacrine cells for parvalbumin, a Ca2+-scavenging protein, was also detected. These abnormalities were accompanied by a decrease in the amplitude of scotopic and photopic a- and b-waves and an increase in the b-wave implicit time, as well as by a lower amplitude and greater latency in oscillatory potentials. These results indicate that rotenone induces loss of vision by promoting photoreceptor cell death and impairment of the dopaminergic retinal system.

Benthic community recovery from brine impact after the implementation of mitigation measures

In many regions, seawater desalination is a growing industry that has its impact on benthic communities. This study analyses the effect on benthic communities of a mitigation measure applied to a brine discharge, using polychaete assemblages as indicator. An eight-year study was conducted at San Pedro del Pinatar (SE Spain) establishing a grid of 12 sites at a depth range of 29–38 m during autumn. Brine discharge started in 2006 and produced a significant decrease in abundance, richness and diversity of polychaete families at the location closest to the discharge, where salinity reached 49. In 2010, a diffuser was deployed at the end of the pipeline in order to increase the mixing, to reduce the impact on benthic communities. After implementation of this mitigation measure, the salinity measured close to discharge was less than 38.5 and a significant recovery in polychaete richness and diversity was detected, to levels similar to those before the discharge. A less evident recovery in abundance was also observed, probably due to different recovery rates of polychaete families. Some families like Paraonidae and Magelonidae were more tolerant to this impact. Others like Syllidae and Capitellidae recovered quickly, although still affected by the discharge, while some families such as Sabellidae and Cirratulidae appeared to recover more slowly.