Jovenes y el sistema pensional colombiano:inequidad intergeneracional

El Sistema Pensional Colombiano se encuentra en una de las etapas más críticas de los últimos años, representando el mayor problema fiscal que enfrentarán las finanzas públicas hoy y en los próximos veinte años. Las modificaciones a la legislación hechas desde 1993 beneficiaron a contados sectores de la sociedad y desencadenaron en onerosos beneficios para unos pocos. Más que hacia un enfoque fiscal, este trabajo busca traducir el problema pensional como un problema de inequidad intergeneracional en el cual, las generaciones actuales y venideras tendrán, además de ahorrar para generar su pensión, cotizar para lograr mantener los beneficios del esquema pensional tal como se contemplan actualmente. Se encuentra que la tendencia de afiliación a los regímenes tiende a ser bastante diferente entre grupos etáreos, mientras que los mayores se concentran en el Régimen de Prima Media, los jóvenes lo hacen en el Régimen de Ahorro Individual. Las condiciones del mercado laboral se presentan como uno de los determinantes del perfil sostenible del sistema pensional pero una mayor tasa de informalidad y un mayor desempleo lo han caracterizado en los últimos cinco años. Se encuentra además que las principales variables que definen el sistema pensional permanecieron constantes a pesar de cambios estructurales de gran envergadura.

Piano Sonata No. 11 in a Major, K. 331

Soitinnus: Piano.

Response to comment on “The response of vegetation on the Andean flank in western Amazonia to Pleistocene climate change” – M.L. Cárdenas et al., Science 331, 1055 (25 February 2011)”.

Puyasena et al. question our interpretation of climate-driven vegetation change on the Andean flank in western Amazonia during the middle Pleistocene and suggest that the use of Podocarpus spp. as a proxy of past climate change should be reassessed. We defend our assertion that vegetation change at the Erazo study site was predominantly driven by climate change due to concomitant changes recorded by multiple taxa in the fossil record.

Concerning CP violation in 331 models

We consider the implementation of CP violation in the context of 331 models. In particular we treat a model where only three scaler triplets are needed in order to give all fermions a mass while keeping neutrino massless. In this case all CP violation is provided by the scalar sector.

Efeitos de Z' nos modelos left-right, B-L e 331

Pós-graduação em Física - IFT

The young stellar cluster [DBS2003] 157 associated with the H ii region GAL 331.31-00.34

We report a study of the stellar content of the near-infrared (NIR) cluster [DBS2003] 157 embedded in the extended H ii region GAL 331.31-00.34, which is associated with the IRAS source 16085-5138. JHK photometry was carried out in order to identify potential ionizing candidates, and the follow-up NIR spectroscopy allowed the spectral classification of some sources, including two O-type stars. A combination of NIR photometry and spectroscopy data was used to obtain the distance of these two stars, with the method of spectroscopic parallax: IRS 298 (O6 V, 3.35 +/- 0.61 kpc) and IRS 339 (O9 V, 3.24 +/- 0.56 kpc). Adopting the average distance of 3.29 +/- 0.58 kpc and comparing the Lyman continuum luminosity of these stars with that required to account for the radio continuum flux of the H ii region, we conclude that these two stars are the ionizing sources of GAL 331.31-00.34. Young stellar objects (YSOs) were searched by using our NIR photometry and mid-infrared (MIR) data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) survey. The analysis of NIR and MIR colourcolour diagrams resulted in 47 YSO candidates. The GLIMPSE counterpart of IRAS 16085-5138, which presents IRAS colour indices compatible with an ultracompact H ii region, has been identified. The analysis of its spectral energy distribution between 2 and m revealed that this source shows a spectral index a= 3.6 between 2 and m, which is typical of a YSO immersed in a protostellar envelope. Lower limits to the bolometric luminosity and the mass of the embedded protostar have been estimated as L= 7.7 x 10(3) L? and M= 10 M?, respectively, which correspond to a B0B1 V zero-age main sequence star.