Julia Annas. Intelligent Virtue, Oxford, Oxford University Press, 2011, VII + 189 pp.

Fil: Crespo, Ricardo. Universidad Nacional de Cuyo

Pigment data set from the SeaWiFS Bio-optical Archive and Storage System (1961-1996)

The oceans play a critical role in the Earth's climate, but unfortunately, the extent of this role is only partially understood. One major obstacle is the difficulty associated with making high-quality, globally distributed observations, a feat that is nearly impossible using only ships and other ocean-based platforms. The data collected by satellite-borne ocean color instruments, however, provide environmental scientists a synoptic look at the productivity and variability of the Earth's oceans and atmosphere, respectively, on high-resolution temporal and spatial scales. Three such instruments, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) onboard ORBIMAGE's OrbView-2 satellite, and two Moderate Resolution Imaging Spectroradiometers (MODIS) onboard the National Aeronautic and Space Administration's (NASA) Terra and Aqua satellites, have been in continuous operation since September 1997, February 2000, and June 2002, respectively. To facilitate the assembly of a suitably accurate data set for climate research, members of the NASA Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project and SeaWiFS Project Offices devote significant attention to the calibration and validation of these and other ocean color instruments. This article briefly presents results from the SIMBIOS and SeaWiFS Project Office's (SSPO) satellite ocean color validation activities and describes the SeaWiFS Bio-optical Archive and Storage System (SeaBASS), a state-of-the-art system for archiving, cataloging, and distributing the in situ data used in these activities.

Biotic and abiotic parameters and cynobacteria abundance during an experimental set-up with varying pCO2 conditions

Heterocystous cyanobacteria of the genus Nodularia form extensive blooms in the Baltic Sea and contribute substantially to the total annual primary production. Moreover, they dispense a large fraction of new nitrogen to the ecosystem when inorganic nitrogen concentration in summer is low. Thus, it is of ecological importance to know how Nodularia will react to future environmental changes, in particular to increasing carbon dioxide (CO2) concentrations and what consequences there might arise for cycling of organic matter in the Baltic Sea. Here, we determined carbon (C) and dinitrogen (N2) fixation rates, growth, elemental stoichiometry of particulate organic matter and nitrogen turnover in batch cultures of the heterocystous cyanobacterium Nodularia spumigena under low (median 315 µatm), mid (median 353 µatm), and high (median 548 µatm) CO2 concentrations. Our results demonstrate an overall stimulating effect of rising pCO2 on C and N2 fixation, as well as on cell growth. An increase in pCO2 during incubation days 0 to 9 resulted in an elevation in growth rate by 84 ± 38% (low vs. high pCO2) and 40 ± 25% (mid vs. high pCO2), as well as in N2 fixation by 93 ± 35% and 38 ± 1%, respectively. C uptake rates showed high standard deviations within treatments and in between sampling days. Nevertheless, C fixation in the high pCO2 treatment was elevated compared to the other two treatments by 97% (high vs. low) and 44% (high vs. mid) at day 0 and day 3, but this effect diminished afterwards. Additionally, elevation in carbon to nitrogen and nitrogen to phosphorus ratios of the particulate biomass formed (POC : POP and PON : POP) was observed at high pCO2. Our findings suggest that rising pCO2 stimulates the growth of heterocystous diazotrophic cyanobacteria, in a similar way as reported for the non-heterocystous diazotroph Trichodesmium. Implications for biogeochemical cycling and food web dynamics, as well as ecological and socio-economical aspects in the Baltic Sea are discussed.

Detrás de una máscara fantasmagórica : Una lectura de La rambla paralela de Fernando Vallejo

Me interesa rastrear en La rambla paralela la tensión entre los procesos de autofiguración y el relato de la propia experiencia de lo íntimo, que en este caso, está asociada con la temporalidad del fantasma y el vacío de la muerte. La potencia de la fantasmagoría está dada por el modo de ser personaje, y por la voz narrativa que no se presenta única ni de forma clara sino en constante desplazamiento. El fantasma está estrechamente vinculado al recuerdo y al proceso melancólico que pone en juego esa particular voz narrativa

Julia Silber : Trayectoria académica en Ciencias de la Educación en la Universidad Nacional de La Plata

Fil: Garatte, Luciana. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Julia Romero, Puig por Puig. Imágenes de un escritor

Fil: Rosano, Susana Luisa María. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Reseña del libro : Memorias del BIM : Biografías. Las víctimas de la Fuerza de Tareas 5 en La Plata, Berisso y Ensenada de Ana Julia Ramírez y Margarita Merbilhaá (editoras)

Fil: Codaro, Laura. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.