Phantom energy from graded algebras

We construct a model of phantom energy using the graded Lie algebra SU(2/1). The negative kinetic energy of the phantom field emerges naturally from the graded Lie algebra, resulting in an equation of state with w<-1. The model also contains ordinary scalar fields and anti-commuting (Grassmann) vector fields which can be taken as two component dark matter. A potential term is generated for both the phantom fields and the ordinary scalar fields via a postulated condensate of the Grassmann vector fields. Since the phantom energy and dark matter arise from the same Lagrangian the phantom energy and dark matter of this model are coupled via the Grassman vector fields. In the model presented here phantom energy and dark matter come from a gauge principle rather than being introduced in an ad hoc manner.Comment: 8 pages no figures; references added and discussion on condensate of vector grassman fields added. To be published MPL

New unidentified H.E.S.S. Galactic sources

H.E.S.S. is one of the most sensitive instruments in the very high energy (VHE; > 100 GeV) gamma-ray domain and has revealed many new sources along the Galactic Plane. After the successful first VHE Galactic Plane Survey of 2004, H.E.S.S. has continued and extended that survey in 2005-2008, discovering a number of new sources, many of which are unidentified. Some of the unidentified H.E.S.S. sources have several positional counterparts and hence several different possible scenarios for the origin of the VHE gamma-ray emission; their identification remains unclear. Others have so far no counterparts at any other wavelength. Particularly, the lack of an X-ray counterpart puts serious constraints on emission models. Several newly discovered and still unidentified VHE sources are reported here.Comment: ICRC 2009 proceeding

Discovery of VHE gamma-rays from the vicinity of the shell-type SNR G318.2+0.1 with H.E.S.S

The on-going H.E.S.S. Galactic Plane Survey continues to reveal new sources of VHE gamma-rays. In particular, recent re-observations of the region around the shell-type supernova remnant (SNR) G318.2+0.1 have resulted in the discovery of statistically-significant very-high-energy (VHE) gamma-ray emission from an extended region. Although the source remains unidentified, archival observations of CO12 in the region provide an opportunity to investigate a potential SNR/molecular cloud interaction. The morphological properties of this newly-discovered VHE gamma-ray source HESSJ1457-593 are presented and discussed in light of the multi-wavelength data available.Comment: 7 pages, 2 figures. Proc. of the 25th TEXAS Symposium on Relativistic Astrophysics. To appear in Proceedings of Scienc

Efeito de dois diluidores sobre a viabilidade In Vitro de sêmen de caprinos.

Procurou-se avaliar a eficiência de dois diluidores (Leite desnatado e Bioxcell - IMV Technologies, Le Aigle, French) sobre a viabilidade espermática através da motilidade e vigor visando a melhoria dos parâmetros pós-conservação

Efeito de diferentes formas de adubação em hortelã rasteira: biomassa e teor de óleo essencial.

Há muitos relatos de que a nutrição interfere na produção de metabólitos secundários em vegetais. Portanto, objetivou-se verificar o efeito de diferentes formas de adubação, na produção de biomassa e no teor de óleo essencial em Mentha x villosa