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Caracterizar las estrategias de movilidad de las sociedades cazadoras-recolectoras-pescadoras en ambientes insulares y litorales es fundamental para comprender la interacción humano-ambiental en el pasado. Las prospecciones en el noreste de la isla Diego Portales, en el mar interior de Última Esperanza (Magallanes, Chile), han permitido documentar ocho yacimientos arqueológicos formados por uno o varios conchales. Todos ellos se hallan ubicados en áreas de la costa al resguardo del viento dominante y con fácil acceso mediante embarcación. Los trabajos arqueológicos en dos de estos yacimientos (Bahía Easter 1 y 2) indican una estrategia de subsistencia similar durante el Holoceno tardío final, basada en el aprovechamiento de la biodiversidad de este ambiente de ecotono, con más de una docena de recursos marinos y terrestres consumidos. Entre éstas destaca en abundancia el huemul (Hippocamelus bisulcus), probablemente cazado en el litoral continental. Teniendo en cuenta las dinámicas de poblamiento y movilidad propuestas desde la etnografía o la arqueología para otras áreas del archipiélago fuego-patagónico, los resultados permiten discutir la reocupación sucesiva de puntos estratégicos de la isla, particularmente en primavera-verano, cuando la encrucijada de caminos y recursos que representa el mar interior de Última Esperanza presentaba alicientes significativos para las comunidades canoeras.

The evolution of soil terrestrial ecosystems is a subject with difficulties to define their maturity and evolutionary state. In the last century, thermodynamics was one of the options considered by ecologists for that goal. Difficulties in quantifying the thermodynamic parameters needed by the evolutionary theories caused that this subject has been practically locked since the end of the last century. Application of thermodynamics needs reactions and one of the main reactions in soil ecosystems are those involved in the decomposition of the soil organic matter. This paper aims to provide an initial step to study those reactions from a thermodynamic perspective. With that goal in mind, thermal analysis and isothermal calorespirometric measurements were made on soil samples collected at three depths in semi-natural oak woodlands at three different sites in southwest Ireland. It is assumed that the organic matter evolves from a less to a higher mature state as soil depth increases. The maturity state could be chemically defined by the redox state. The proposed methods yield the enthalpy change, Gibbs energy change and entropy change for the microbial catabolism and combustion reactions of the soil organic matter. The degree of reduction was calculated by the enthalpy changes. Results show the soil organic matter becomes more reduced from the soil organic surface to mineral soils. The top layer is characterized by high carbon content, organic materials with low energy content per Cmole, and fast biodegradation rates. Mineral soils are characterized by low carbon content, organic materials with high energy content per Cmole, and slow biodegradation rates. Values obtained for the entropy change were sensitive to these differences among the different soil layers. These results contribute to unlock the thermodynamics of the soil reactions and to develop the bioenergetics of soil ecosystems., It was partially funded by "Economía, Emprego e Industria" of the Galician Government (OTR02794/AGI/CISIC I+D+I 2016, OTR04174/AGI/CISIC I+D+I 2017)

B-HT 920 at low doses inhibited the accumulation of DOPA following treatment with reserpine and a DOPA decarboxylase inhibitor in the dopamine-, but not in the noradrenaline-predominant regions of the rat brain. B-HT 933 selectively inhibited this DOPA accumulation in the noradrenaline-predominant regions. These effects of B-HT 920 and B-HT 933 were completely antagonized by haloperidol and yohimbine, respectively. The rat motor activity was reduced by B-HT 920 and it was restored following apomorphine. B-HT 933 decreased the motor activity by a yohimbine-sensitive mechanism. The results indicate that B-HT 920 can selectively and potently stimulate the dopamine autoreceptors whereas B-HT 933 can selectively stimulate the noradrenaline autoreceptors.