Electroweak right-handed neutrinos and new signals at the LHC

We explore in detail the Higgs phenomenology that results in a model where right-handed neutrinos have a mass scale of the order of the electroweak scale. In this model all scales arise from spontaneous symmetry breaking, and this is achieved with a Higgs sector that includes an extra Higgs singlet in addition to the standard model Higgs doublet. The scalar spectrum includes two neutral CP-even states ($h$ and $H$ with $m_{h} < m_{H}$)and a neutral CP-odd state ($\sigma$) that can be identified as a pseudo-Majoron. The parameter of the Higgs potential are constrained using a perturbativity criteria. Higgs BR and cross-sections are discussed, with special emphasis on the detection at the LHC.Comment: 22 pages, 10 figure

Implicit equations of non-degenerate rational Bezier quadric triangles

In this paper we review the derivation of implicit equations for non-degenerate quadric patches in rational Bezier triangular form. These are the case of Steiner surfaces of degree two. We derive the bilinear forms for such quadrics in a coordinate-free fashion in terms of their control net and their list of weights in a suitable form. Our construction relies on projective geometry and is grounded on the pencil of quadrics circumscribed to a tetrahedron formed by vertices of the control net and an additional point which is required for the Steiner surface to be a non-degenerate quadric.Comment: 10 pages, 8th International Conference Curves and Surfaces, Paris, France, June 12-18, 201

Infecção pelo VIH na Grávida e Criança

A utilização de terapêutica anti-retrovírica durante a gravidez, a cesareana e a não amamentação tornaram possível, nos países mais desenvolvidos, reduzir a taxa de transmissão peri-natal

Appalachian Farmers: Building Value from Values

This trio of authors has presented a microcosm of values-based shared business practices, involving local food production and distribution in a small, rural Appalachian region in the United States. They focus upon the collective activities of a group committed to advancing local business practices while eliminating unnecessary transportation costs, boosting the region’s economic infrastructure, and most importantly, bringing people together to share experiences and pass along knowledge designed to benefit their communities and generate a sustainable agricultural-based economy

The catalogue of OB associations in IC 1613

We present a catalogue of OB associations in IC 1613. Using an automatic and objective method (Battinelli's 1991 technique) 60 objects were found. The size distribution reveals a significant peak at about 60 parsecs if a distance modulus of 24.27 mag is assumed. Spatial distributions of the detected associations and H II regions are strongly correlated.Comment: 5 pages, 3 figures, A&A accepte