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The Mid-infrared Interferometric instrument (MIDI) at the Very Large Telescope Interferometer (VLTI) has been used to spatially resolve the dust-forming region of 14 asymptotic giant branch (AGB) stars with different chemistry (O-rich and C-rich) and variability types (Miras, semi-regular, and irregular variables). The main goal of the programme was to detect deviations from spherical symmetry in the dust-forming region of these stars. All the stars of the sample are well resolved with the VLTI, and five are asymmetric and O-rich. This finding contrasts with observations in the near-infrared, where the C-rich objects are found to be more asymmetric than the O-rich ones. The nature of the asymmetric structures so far detected (dusty discs versus blobs)remains uncertain and will require imaging on milli-arcsecond scales., Published in The Messenger vol. 168, pp. 28-31, June 2017.

Method: In an accompanying paper (arXiv: 1705.00886) we determined luminosity and effective temperature for the 335 T2Cs and ACs in the LMC and SMC discovered in the OGLE-III survey, by constructing the spectral energy distribution (SED) and fitting this with model atmospheres and a dust radiative transfer model (in the case of dust excess). Building on these results we study the PL and PR relations. Using existing pulsation models for RR Lyrae and classical Cepheids we derive the period-luminosity-mass-temperature-metallicity relations, and then estimate the pulsation mass. Results: The PL relation for the T2Cs does not appear to depend on metallicity, and, excluding the dusty RV Tau stars, is $M_{\rm bol}= +0.12 -1.78 \log P$ (for $P < 50$ days). Relations for fundamental and first overtone LMC ACs are also presented. The PR relation for T2C also shows little or no dependence on metallicity or period. Our preferred relation combines SMC and LMC stars and all T2C subclasses, and is $\log R = 0.846 + 0.521 \log P$. Relations for fundamental and first overtone LMC ACs are also presented. The pulsation masses from the RR Lyrae and classical Cepheid pulsation models agree well for the short period T2Cs, the BL Her subtype, and ACs, and are consistent with estimates in the literature, i.e. $M_{\rm BLH} \sim 0.49$ \msol\ and $M_{\rm AC} ~\sim 1.3$ \msol, respectively. The masses of the W Vir appear similar to the BL Her. The situation for the pWVir and RV Tau stars is less clear. For many RV Tau the masses are in conflict with the standard picture of (single-star) post-AGB evolution, the masses being either too large ($\gtrsim$ 1 \msol) or too small ($\lesssim$ 0.4 \msol)., A&A accepted

(Abridged) I cross-correlate the OGLE database of Cepheids in the Large and Small Magellanic Clouds (MCs) with the second incremental release of the 2MASS JHK survey, and the DENIS IJK point source catalog towards the MCs. Of the 3384 Cepheids in OGLE in both Clouds, 1745 have a counterpart in the 2MASS survey within an 1" radius and good-photometry in all three bands. Only 173 have a counterpart in the DENIS survey within an 1" radius and good-photometry in all three bands. The reason for this difference is that the limiting magnitudes of the 2MASS survey are considerably fainter than for DENIS. To describe to first order the geometrical configuration of the MCs a plane is fitted to the reddening-free Wesenheit (W) index. For the LMC an inclination angle of 18 $\pm$ 3\degr is derived, for the SMC a value of $i = 68 \pm 2$\degr is derived. These results are being used to take out the effect that some Cepheids are closer to the observer than others. Using single-epoch 2MASS data for the OGLE Cepheids, PL-relations are fitted in JHK for both Fundamental mode (FU) and First-overtone (FO) pulsators, taking out the effect of the inclined disk. The derived PL-relations are used to derive a relative distance modulus of 0.50 \pm 0.02 between SMC and LMC assuming no metallicity correction. Combining the zero points of the Galactic and MCs PL-relations distance moduli of 18.60 $\pm$ 0.11 (based on W) and 18.55 $\pm$ 0.17 (based on K) to the LMC, and of 19.11 $\pm$ 0.11 (W) and 19.04 $\pm$ 0.17 (K) to the SMC are derived (without taking into account possible metallicity corrections).

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