The Phoenix Deep Survey: The 1.4 GHz microJansky catalogue

The initial Phoenix Deep Survey (PDS) observations with the Australia Telescope Compact Array have been supplemented by additional 1.4 GHz observations over the past few years. Here we present details of the construction of a new mosaic image covering an area of 4.56 square degrees, an investigation of the reliability of the source measurements, and the 1.4 GHz source counts for the compiled radio catalogue. The mosaic achieves a 1-sigma rms noise of 12 microJy at its most sensitive, and a homogeneous radio-selected catalogue of over 2000 sources reaching flux densities as faint as 60 microJy has been compiled. The source parameter measurements are found to be consistent with the expected uncertainties from the image noise levels and the Gaussian source fitting procedure. A radio-selected sample avoids the complications of obscuration associated with optically-selected samples, and by utilising complementary PDS observations including multicolour optical, near-infrared and spectroscopic data, this radio catalogue will be used in a detailed investigation of the evolution in star-formation spanning the redshift range 0 < z < 1. The homogeneity of the catalogue ensures a consistent picture of galaxy evolution can be developed over the full cosmologically significant redshift range of interest. The 1.4 GHz mosaic image and the source catalogue are available on the web at http://www.atnf.csiro.au/~ahopkins/phoenix/ or from the authors by request.Comment: 16 pages, 11 figures, 4 tables. Accepted for publication by A

Do fiscal imbalances deteriorate sovereign debt ratings ?

We use sovereign debt rating estimations from Afonso, Gomes and Rother (2009, 2011) for Fitch, Moody’s, and Standard & Poor’s, to assess to what extent the recent fiscal imbalances are being reflected on the sovereign debt notations. With macro and fiscal data up to 2010, and macro and fiscal projections, we obtain the expected rating for several OECD countries. The answer to the title question is yes, but in a diverse way for each country. Our average model predictions point to a heterogeneous behaviour of rating agencies across countries

Discrete uncertainty principles and sparse signal processing

We develop new discrete uncertainty principles in terms of numerical sparsity, which is a continuous proxy for the 0-norm. Unlike traditional sparsity, the continuity of numerical sparsity naturally accommodates functions which are nearly sparse. After studying these principles and the functions that achieve exact or near equality in them, we identify certain consequences in a number of sparse signal processing applications

Radio observations of the CDF-South: a possible link between radio emission and star formation in X-ray selected AGN

We explore the nature of the radio emission of X-ray selected AGN by combining deep radio (1.4GHz; 60micro-Jy) and X-ray data with multiwavelength (optical, mid-infrared) observations in the Extended Chandra Deep Field South (E-CDFS). The fraction of radio detected X-ray sources increases from 9% in the E-CDFS to 14% in the central region of this field, which has deeper X-ray coverage from the 1Ms CDFS. We find evidence that the radio emission of up to 60% of the hard X-ray/radio matched AGN is likely associated with star-formation in the host galaxy. Firstly, the mid-IR (24micron) properties of these sources are consistent with the infrared/radio correlation of starbursts. Secondly, most of them are found in galaxies with blue rest-frame optical colours (U-V), suggesting a young stellar population. On the contrary, X-ray/radio matched AGN which are not detected in the mid-infrared have red U-V colours suggesting their radio emission is associated with AGN activity. We also find no evidence for a population of heavily obscured radio-selected AGN that are not detected in X-rays. Finally, we do no confirm previous claims for a correlation between radio emission and X-ray obscuration. Assuming that the radio continuum measures star-formation, this finding is against models where the dust and gas clouds associated with circumnuclear starbursts are spherically blocking our view to the central engine.Comment: Accepted by A&

Suplementação mineral para bovinos de corte no Pantanal (Sub-região da Nhecolândia).

Os levantamentos de concentrações de minerais nas pastagens e nos tecidos de bovinos feitos em algumas sub-regiões do Pantanal indicaram ocorrência de deficiências acentuadas, principalmente de cálcio e fósforo. Baseado nesse trabalho, a Embrapa Pantanal elaborou cinco fórmulas de suplemento mineral para diferentes sub-regiões do Pantanal

Limites do direito autoral e de software

Apresenta as principais informações sobre os limites da proteção autoral, abordando, também, os direitos de software. Presente na Atividade 2, Unidade 1 do Curso de Direitos Autorais ofertado pela Universidade Aberta do SUS

Criador e titular dos direitos patrimoniais de uma obra

Apresenta as diferenças entre o autor e titular dos direitos patrimoniais de uma obra, bem como a relação entre eles. Vídeo da atividade 4, unidade 1, do Curso de Direitos Autorais ofertado pela Universidade Aberta do SU

Obras audiovisuais e colaborativas [direitos autorais]

Aborda os direitos autorais nas obras audiovisuais, obras coletivas, obras colaborativas e nas obras compostas. Vídeo da atividade 5, unidade 1, do Curso de Direitos Autorais, ofertado pela Universidade Aberta do SU