Catherine Charbonnel

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Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the primordial light elements with an unprecedented precision. In the case of 7 Li, the CMB+SBBN value is significantly(More)
This study calls attention to the importance of properly coupling the molecular opacities to the actual surface abundances of TP-AGB stars that experience the third dredge-up and/or hot-bottom burning, i.e. with surface abundances of carbon and oxygen varying with time. New TP-AGB calculations with variable opacities – replacing the usually adopted(More)
We have computed new solar models using the same stellar evolution code as described in Charbonnel, Vauclair and Zahn (1992). This code, originating from Geneva, now includes the computation of element segregation for helium and 12 heavier isotopes. It may also include any type of mixing of the stellar gas, provided this mixing can be parametrized with an(More)
  • A L Ebre, P De Laverny, J R De Medeiros, C Charbonnel, L Da Silva
  • 1999
We have obtained new high resolution spectroscopic observations of the lithium line at 6707.81Å and derived lithium abundances (A Li) by spectral synthesis for a sample of about 120 F-, G-and K-type Population I subgiant stars. For each of these stars, high precision rotational velocity obtained with the CORAVEL spectrometer is available. We present the(More)
Context. To alleviate the discrepancy between the prediction of the primordial lithium abundance in the universe and the abundances observed in Pop II dwarfs and subgiant stars, it has been suggested that the stars observable today have undergone photospheric depletion of lithium. Aims. To identify the cause of this depletion, it is important to accurately(More)
BACKGROUND We recently identified and validated UBE2C RNA as a prognostic marker in 252 node-positive (N+) breast cancers by means of a microarray study. The aim of this study was to validate UBE2C protein as a prognostic marker in N+ breast cancer by immunohistochemistry (IHC). METHODS To this end, 92 paraffin-embedded blocks were used. The impact of(More)
BACKGROUND Anti-apoptotic signals induced downstream of HER2 are known to contribute to the resistance to current treatments of breast cancer cells that overexpress this member of the EGFR family. Whether or not some of these signals are also involved in tumor maintenance by counteracting constitutive death signals is much less understood. To address this,(More)
  • C Charbonnel, W Däppen, D Schaerer, P A Bernasconi, A Maeder, G Meynet +1 other
  • 1998
We present stellar evolutionary models covering the mass range from 0.4 to 1 M ⊙ calculated for metal-licities Z=0.020 and 0.001 with the MHD equation of state (Hummer & Mihalas, 1988; Mihalas et al. 1988; Däppen et al. 1988). A parallel calculation using the OPAL (Rogers et al. 1996) equation of state has been made to demonstrate the adequacy of the MHD(More)
We perform an evolutionary multivariate analysis of a sample of 54 Galactic globular clusters with high-quality colour-magnitude diagrams and well-determined ages. The four parameters adopted for the analysis are: metallicity, age, maximum temperature on the horizontal branch, and absolute V magnitude. Our cladistic analysis breaks the sample into three(More)