Dissipative phenomena in extended-bodies interactions I: Methods Dwarf galaxies of the Local Group and their synthetic CMDs

Dissipative phenomena occurring during the orbital evolution of a dwarf satellite galaxy around a host galaxy may leave signatures in the star formation activity and signatures in the colour magnitude diagram of the galaxy stellar content. Our goal is to reach a simple and qualitative description of the these complicated phenomena. We develop an analytical and numerical technique able to study ram pressure, Kelvin-Helmholtz instability, Rayleigh-Taylor and tidal forces acting on the star formation processes in molecular clouds. We consider it together with synthetic colour magnitude diagrams techniques. We developed a method to investigate the connections existing between gas consumption processes and star formation processes in the context of the two extended-body interaction with special attention to the dwarf galaxies dynamical regime.Comment: Accepted on A&

The Multiplicity of Main Sequence Turnoffs in Globular Clusters

We present color-magnitude diagrams of globular clusters for models with self-enrichment and pre-enrichment. The models with self-enrichment turn out to have two or more main sequence turnoff points in the color-magnitude diagram if the fraction of mass lost by the globular cluster under supernova explosions does not exceed 95-97%. The models with pre-enrichment can have only one main sequence turnoff point. We argue that the cluster wCen evolved according to a self-enrichment scenario.Comment: 13 pages, 7 figure

Nucleotide sequence of the Saccharomyces cerevisiae MET25 gene.

To elucidate further the molecular basis of the specific regulatory mechanism modulating the expression of the genes implicated in methionine metabolism, we have cloned and characterized two genes, MET3 and MET25, and shown that the regulation of their expression is transcriptional. The sequence of the cloned yeast MET25 gene which encodes the O-acetyl homoserine - O-acetyl serine (OAH-OAS) sulfhydrylase is reported here along with its 5' and 3' flanking regions. The amino acid composition predicted from the DNA sequence is in good agreement with that determined by hydrolysis of the purified enzyme. In the 5' flanking region the signal for general amino acid control was not found, corroborating our previous finding that the synthesis of OAH-OAS sulfhydrylase is not submitted to general control. The transcription start points have been determined. The 5' and 3' flanking regions of the MET25 gene suggest initiation and termination signals similar to those associated with other yeast genes