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Blue compact dwarf (BCD) galaxies are low-luminosity (absolute K-band magnitude, M K  > -21 mag) 1 , metal-poor (1/50 ≤ Z/Z ⊙  ≤ 1/2, where Z is the metallicity in terms of the solar metallicity Z ⊙ ) 2 , centrally concentrated 3 galaxies with bright clumps of star formation 4 . Cosmological surface-brightness dimming 5 and the small size of BCDs limit their detection at high redshifts, making their formation process difficult to observe. Observations of BCDs are needed at intermediate redshifts, where they are still young enough to show their formative stages, particularly in the outer regions where cosmic gas accretion should drive evolution. Here we report the observation of excess far-ultraviolet (FUV) emission in the outer regions of 11 BCDs in the GOODS South field at redshifts between 0.1 and 0.24, corresponding to look-back times of 1.3-2.8 billion years in standard cosmology. These observations were made by the Ultra-Violet Imaging Telescope 6 on AstroSat 7 . For ten BCDs, the radial profiles of the intrinsic FUV emission, corrected for the instrument point spread function, have larger scale lengths than their optical counterparts observed with the Hubble Space Telescope. Such shallow FUV profiles suggest extended star formation in cosmically accreting disks. Clumpy structure in the FUV also suggests that the outer FUV disks are gravitationally unstable. Dynamical friction on the clumps drives them inwards at an average rate exceeding 10 6  solar masses per billion years., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

With growing concerns about global warming, it has become urgent and critical to capture carbon from various emission sources (such as power plants) and even directly from air. Recent advances in materials research permit the design of various efficient approaches for capturing CO 2 with high selectivity over other gases. Here, we show that crown nanopores (resembling crown ethers) embedded in graphene can efficaciously allow CO 2 to pass and block other flue gas components (such as N 2 and O 2 ). We carried out extensive density functional theory-based calculations as well as classical and ab initio molecular dynamics simulations to reveal the energetics and dynamics of gas transport through crown nanopores. Our results highlight that the designed crown nanopores in graphene possess not only an excellent selectivity for CO 2 separation/capture but also fast transport (flow) rates, which are ideal for the treatment of flue gas in power plants.

We show that smooth domain walls in ultrathin ferromagnetic films can develop jaggedness even in the absence of random defects when confronted with a sufficiently large tilt between the uniaxial anisotropy direction and the external field. From the Kerr imaging of 0.7 nm thin Co films and from numerical simulations we report a previously unseen runaway fingerlike instability in a magnetic wall that begins on nanoscales but grows to macroscopic lengths for sufficiently large tilt angles. A threshold for the instability is controlled by the ferromagnet's parameters and the applied field.