Structure of the Isovector Dipole Resonance in Neutron-Rich 60Ca^{60}Ca Nucleus and Direct Decay from Pygmy Resonance

The structure of the isovector dipole resonance in neutron-rich calcium isotope, $^{60}Ca$, has been investigated by implementing a careful treatment of the differences of neutron and proton radii in the continuum random phase approximation ($RPA$). The calculations have taken into account the current estimates of the neutron skin. The estimates of the escape widths for direct neutron decay from the pygmy dipole resonance ($PDR$) were shown rather wide, implicating a strong coupling to the continuum. The width of the giant dipole resonance ($GDR$) was evaluated, bringing on a detailed discussion about its microscopic structure.Comment: 13 pages, 2 figures, RevTex

Biophysic assessment of ecosystem services in the Arroyo Grande basin, Tunuyán, Mendoza

La cuenca del Arroyo Grande (Valle de Uco, Tunuyán, Mendoza) es un área que presenta cambios clave en el uso de sus recursos, producidos principalmente por los nuevos emprendimientos vitivinícolas y facilitados por la aplicación del riego presurizado. En estos cambios primó la decisión privada y la diversidad de criterios de gestión ambiental. Con el objetivo de evaluar la capacidad funcional de los dos ecosistemas principales, el monte nativo y el agroecosistema, y la provisión relativa de servicios ecosistémicos (SE) en la cuenca del Arroyo Grande, se aplicó una metodología basada en el protocolo ECOSER 1.0 mediante un sistema de información geográfica. A partir de información biofísica del área se ubicaron en el espacio los tipos de ecosistemas dominantes (TED) y se consideraron cuatro funciones ecosistémicas (FE). La identificación de cada SE y su provisión relativa se calculó como la combinación lineal del flujo de cada FE ponderado por su aporte relativo al correspondiente SE. Por último, la provisión de SE se evaluó espacialmente mediante la generación de mapas. Los resultados muestran al agroecosistema como proveedor de un mayor número de SE, dentro de los ocho analizados. Entre ellos figura la producción agrícola, que incluye cultivos, ganado y forestación. El monte nativo provee en mayor proporción SE de soporte y aprovisionamiento, relacionados con la provisión de agua y su calidad, que a su vez son esenciales para el agroecosistema. En conclusión, existen diferencias en la provisión de SE según los ecosistemas, y aquellos que brinda el agroecosistema dependen de otros SE, proporcionados antes por el monte nativo.The Arroyo Grande basin (Valle de Uco, Tunuyán, Mendoza) is an area that shows major changes in the use of natural resources, primarily generated by new investments for wine-grape production, and facilitated by the application of pressurized irrigation. Private decisions, as well as a diversity of criteria for environmental management, prevailed in those changes. In order to evaluate the functional capacity of the two major ecosystems identified, shrubland and agroecosystem, and their relative provision of ecosystem services (ES) in the Arroyo Grande basin, we applied a methodology based on the ECOSER 1.0 protocol, using a geographic information system. Using biophysical information from the area, we identified and mapped the dominant ecosystems types (TDE). We considered four ecosystem functions (EF) and eight ES. The identification of each ES and its relative provision was calculated as a linear combination of the flow of each EF weighted by their relative contribution to the corresponding ES. Finally, through the generation of maps, we evaluated spatially ES provision. Results show the agroecosystem provides a larger number of ES, including agricultural production as crops, livestock and forestry. The shrubland provides a greater proportion of supporting and provisioning ES, related to water supply and quality, which, in turn, are essential for the agroecosystem. In conclusion, there are differences in the provision of ES according to the ecosystems, and those ES provided by the agroecosystem depend on another ES previously provided by the shrubland

Pml represses tumour progression through inhibition of mTOR

The promyelocytic leukaemia gene PML is a pleiotropic tumour suppressor. We have recently demonstrated that PML opposes mTOR-HIF1α-VEGF signalling in hypoxia. To determine the relevance of PML-mTOR antagonism in tumourigenesis, we have intercrossed Pml null mice with Tsc2 heterozygous mice, which develop kidney cysts and carcinomas exhibiting mTOR upregulation. We find that combined inactivation of Pml and Tsc2 results in aberrant TORC1 activity both in pre-tumoural kidneys as well as in kidney lesions. Such increase correlates with a marked acceleration in tumour progression, impacting on both the biology and histology of kidney carcinomas. Also, Pml inactivation decreases the rate of loss of heterozygosity (LOH) for the wt Tsc2 allele. Interestingly, however, aberrant TORC1 activity does not accelerate renal cystogenesis in Tsc2/Pml mutants. Our data demonstrate that activation of mTOR is critical for tumour progression, but not for tumour initiation in the kidney