Structures of tetrasilylmethane derivatives (XMe2Si)2C(SiMe3)2 (X = H, Cl, Br) in the gas phase, and their dynamic structures in solution

The structures of the molecules (XMe2Si)2C(SiMe3)2, where X = H, Cl, Br, have been determined by gas electron diffraction (GED) using the SARACEN method of restraints, with all analogues existing in the gas phase as mixtures of C1- and C2-symmetric conformers. Variable temperature 1H and 29Si solution-phase NMR studies, as well as 13C NMR and 1H/29Si NMR shift correlation and 1H NMR saturation transfer experiments for the chlorine and bromine analogues, are reported. At low temperatures in solution there appear to be two C1 conformers and two C2 conformers, agreeing with the isolated-molecule calculations used to guide the electron diffraction refinements. For (HMe2Si)2C(SiMe3)2 the calculations indicated six conformers close in energy, and these were modeled in the GED refinement

Etude de l'activité des systèmes sympathique et rénine-angiotensine à la phase aiguë de l'infarctus myocardique.

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Recommandations relatives à la prévention des maladies cardiovasculaires en pratique clinique. Groupe de travail belge de prévention des maladies cardiovasculaires

Since more than 15 years, expert groups and various European Scientific Societies have written Guidelines on Cardiovascular Disease Prevention. Because of the rapid evolution of science, it is necessary to adapt regularly these guidelines. The last version dates from 2007 and has been written by the " Fourth Joint Task Force of European and other Societies on Cardiovascular Disease Prevention in Clinical Practice ". In this issue, the more recent Guidelines are summarised and we focus on highlighting the aspects of these Guidelines that have changed since the previous version published in this journal in 2005