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Dank eines Bollywood-Films wird in Indien uber Damenbinden geredet. Doch es braucht mehr, um ein kulturell verwurzeltes Tabu zu uberwinden. Fur indische Frauen geht es bei diesem Thema um ihre Gesundheit — und noch mehr.

Nature 502, 346–349 (2013); doi:10.1038/nature12569 In this Letter, we have identified an important error affecting Fig. 4 and Extended Data Fig. 6, as well as the values of some parameters derived from our model fits. We stress that this error in no way affects the discussion or the conclusions. Inbuilding the bolometric light curve of the superluminous supernova PTF 12dam, our code assumed that photometry from the Swift satellite was calibrated in the Vega magnitude system.

An all-sky redshift survey of galaxies detected by IRAS (the Infrared Astronomical Satellite) has been used to map the Universe out to 140h−1 Mpc (the Hubble constant H0 =100h km s−1 Mpc−1). Well-known superclusters and voids are seen, as are others not previously identified. The inferred underlying distribution of density is found to be skewed to high densities (the voids are larger than the superclusters but depart less from the mean density); and there is more structure on large scales than is predicted by the standard cold dark matter theory of galaxy formation.

Recent observations1–3 indicate that large regions of the Universe 60 h−1 Mpc in radius (where h is the Hubble constant in units of 100 km s−1 Mpc−1) may be streaming coherently with velocities up to 1,000 km s−1 with respect to the rest frame determined by the cosmic microwave background. In this letter the peculiar velocities which arise in the cosmic string theory of galaxy formation are estimated using numerical simulations. In contrast to models of formation of structure based on primordial linear energy density fluctuations with random phases, the distribution of velocities is highly non-gaussian on scales smaller than 50 h−1 Mpc. The most likely velocities are approximately scale independent on scales between 5 and 50 h−1 Mpc.

There has been much interest in the cosmological consequences of line-like topological defects (‘cosmic strings’) which may be produced in a phase transition in the early Universe1–8. Such strings would produce density fluctuations on a broad range of scales and may have been responsible for the formation of galaxies. In view of this possibility, it would be useful to have more direct evidence of the existence of strings than the observed clustering of matter. We show here that cosmic strings would generate anisotropy of the microwave background temperature with a very distinctive feature; the temperature would have steplike discontinuities on curves on the sky. Present anisotropy measurements limit the line density parameter, Gμ to be