Astronomía, astrología y política en Marco Tulio Cicerón S.I A.C y en Marco Manilio S.I D.C.

Realizamos un estudio de la "simpatía cósmica": la visión filosófica unificada y armónica del universo propia del Estoicismo Medio de Panecio y Posidonio y su influencia en estos dos autores. Analizamos la relación de la astronomía y de la astrología vinculada al aspecto político-filosófico en De Republica de Cicerón, y en las Astronomica de Manilio: planteamos interrogantes acerca de la causa de esta vinculación, e indagamos en la posible necesidad, en el caso de Manilio, de enmascarar políticamente una posición filosófica. Las referencias a Augusto en la obra de Manilio, a los grandes héroes de Roma en la de Cicerón, o el hecho de "mostrar" la grandeza de Roma, o la buena estrella de sus gobernantes son algunas de las estrategias argumentativas utilizadas: el empleo de recursos retóricos como la "escenificación" y la "analogía", entre otros, "ayudarían" a sostener una determinada postura ideológica política y filosófica en los mencionados autores

Representaciones de la vejez y formas del discurso ejemplar romano durante el S. I d.C.

Examinaremos cómo la vejez en el corpus fedriano se configura a partir de los diálogos que este establece con sus contextos literarios y culturales. Así, la construcción de la ancianidad femenina incorpora estereotipos cómicosatíricos que evidencian la perspectiva romanocéntrica desde la que el género se reformula (Phaed.2.2 y 3.1). Por su parte, la debilidad atribuida a los ancianos (Phaed.1.15 y 1.21) -leída en contraposición con la fortaleza que su contemporáneo, Valerio Máximo, adjudica a la ancianidad modélica en sus exempla (V. Max. 8.13)- contribuye a la construcción de la máscara del fabulista como sujeto marginal (3. 9 y 3. epil.).

(Figures S2a-c) Phase diagrams of the upper crust, the lower crust and the upper mantle based on averaged compositions of the oceanic crust and mantle

The age of the subducting Nazca Plate off Chile increases northwards from 0 Ma at the Chile Triple Junction (46°S) to 37 Ma at the latitude of Valparaíso (32°S). Age-related variations in the thermal state of the subducting plate impact on (a) the water influx to the subduction zone, as well as on (b) the volumes of water that are released under the continental forearc or, alternatively, carried beyond the arc. Southern Central Chile is an ideal setting to study this effect, because other factors for the subduction zone water budget appear constant. We determine the water influx by calculating the crustal water uptake and by modeling the upper mantle serpentinization at the outer rise of the Chile Trench. The water release under forearc and arc is determined by coupling FEM thermal models of the subducting plate with stability fields of water-releasing mineral reactions for upper and lower crust and hydrated mantle. Results show that both the influx of water stored in, and the outflux of water released from upper crust, lower crust and mantle vary drastically over segment boundaries. In particular, the oldest and coldest segments carry roughly twice as much water into the subduction zone as the youngest and hottest segments, but their release flux to the forearc is only about one fourth of the latter. This high variability over a subduction zone of < 1500 km length shows that it is insufficient to consider subduction zones as uniform entities in global estimates of subduction zone fluxes. This article is protected by copyright. All rights reserved.

Aprubt climate change events in the Northeastern Atlantic Ocean

The western Iberian margin has been one of the key locations to study abrupt glacial climate change and associated interhemispheric linkages. The regional variability in the response to those events is being studied by combining a multitude of published and new records. Looking at the trend from Marine Isotope Stage (MIS) 10 to 2, the planktic foraminifer data, conform with the alkenone record of Martrat et al. [2007], shows that abrupt climate change events, especially the Heinrich events, became more frequent and their impacts in general stronger during the last glacial cycle. However, there were two older periods with strong impacts on the Atlantic meridional overturning circulation (AMOC): the Heinrich-type event associated with Termination (T) IV and the one occurring during MIS 8 (269 to 265 ka). During the Heinrich stadials of the last glacial cycle, the polar front reached the northern Iberian margin (ca. 41°N), while the arctic front was located in the vicinity of 39°N. During all the glacial periods studied, there existed a boundary at the latter latitude, either the arctic front during extreme cold events or the subarctic front during less strong coolings or warmer glacials. Along with these fronts sea surface temperatures (SST) increased southward by about 1°C per one degree of latitude leading to steep temperature gradients in the eastern North Atlantic and pointing to a close vicinity between subpolar and subtropical waters. The southern Iberian margin was always bathed by subtropical water masses - surface and/ or subsurface ones -, but there were periods when these waters also penetrated northward to 40.6°N. Glacial hydrographic conditions were similar during MIS 2 and 4, but much different during MIS 6. MIS 6 was a warmer glacial with the polar front being located further to the north allowing the subtropical surface and subsurface waters to reach at minimum as far north as 40.6°N and resulting in relative stable conditions on the southern margin. In the vertical structure, the Greenland-type climate oscillations during the last glacial cycle were recorded down to 2465 m during the Heinrich stadials, i.e. slightly deeper than in the western basin. This deeper boundary is related to the admixing of Mediterranean Outflow Water, which also explains the better ventilation of the intermediate-depth water column on the Iberian margin. This compilation revealed that latitudinal, longitudinal and vertical gradients existed in the waters along the Iberian margin, i.e. in a relative restricted area, but sufficient paleo-data exists now to validate regional climate models for abrupt climate change events in the northeastern North Atlantic Ocean.