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  1. null (Ed.)
    ABSTRACT Star-forming galaxies are rich reservoirs of dust, both warm and cold. But the cold dust emission is faint alongside the relatively bright and ubiquitous warm dust emission. Recently, evidence for a very cold dust (VCD) component has also been revealed via millimetre/submillimetre (mm/sub-mm) photometry of some galaxies. This component, despite being the most massive of the three dust components in star-forming galaxies, is by virtue of its very low temperature, faint and hard to detect together with the relatively bright emission from warmer dust. Here, we analyse the dust content of a carefully selected sample of four galaxies detected by IRAS, WISE, and South Pole Telescope (SPT), whose spectral energy distributions (SEDs) were modelled to constrain their potential cold dust content. Low-frequency radio observations using the Giant Metrewave Radio Telescope (GMRT) were carried out to segregate cold dust emission from non-thermal emission in mm/sub-mm wavebands. We also carried out AstroSat/Ultraviolet Imaging Telescope (UVIT) observations for some galaxies to constrain their SED at shorter wavelengths so as to enforce energy balance for the SED modelling. We constructed their SEDs across a vast wavelength range (extending from UV to radio frequencies) by assembling global photometry from GALEX FUV + NUV, UVIT, Johnson BRI, 2MASS, WISE, IRAC, IRAS, AKARI, ISO PHOT, Planck HFI, SPT, and GMRT. The SEDs were modelled with cigale to estimate their basic properties, in particular to constrain the masses of their total and VCD components. Although the galaxies’ dust masses are dominated by warmer dust, there are hints of VCD in two of the targets, NGC 7496 and NGC 7590. 
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  2. Abstract

    Osteosarcoma is a highly aggressive malignancy for which treatment has remained essentially unchanged for years. Our previous studies found that the F‐box protein SKP2 is overexpressed in osteosarcoma, acting as a proto‐oncogene; p27Kip1(p27) is an inhibitor of cyclin‐dependent kinases and a downstream substrate of SKP2‐mediated ubiquitination. Overexpression of SKP2 and underexpression of p27 are common characteristics of cancer cells. The SCFSKP2E3 ligase ubiquitinates Thr187‐phosphorylated p27 for proteasome degradation, which can be abolished by a Thr187Ala knock‐in (p27T187AKI) mutation.RB1andTP53are two major tumor suppressors commonly coinactivated in osteosarcoma. We generated a mouse model with a double knockout (DKO) ofRb1andTrp53within cells of the osteoblastic lineage, which developed osteosarcoma with full penetrance. When p27T187AKI mice were crossed on to the DKO background, p27T187Aprotein was found to accumulate in osteosarcoma tumor tissues. Furthermore, p27T187Apromoted apoptosis in DKO tumors, slowed disease progression, and significantly prolonged overall survival. RNA sequencing analysis also linked the SCFSKP2–p27T187Aaxis to potentially reduced cancer stemness. Given thatRB1andTP53loss or coinactivation is common in human osteosarcoma, our study suggests that inhibiting the SKP2–p27 axis may represent a desirable therapeutic strategy for this cancer.

     
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