The transcription factor CCAAT enhancer-binding protein ␣ (C/EBP␣) is a tumor suppressor in myeloid cells and inhibits proliferation in all cell types examined. C/EBP␣ interacts with the SWI/SNF chromatinremodeling complex during the regulation of differentiation-specific genes. Here we show that C/EBP␣ fails to suppress proliferation in SWI/SNF defective cell lines after knock-down of SWI/SNF core components or after deletion of the SWI/SNF interaction domain in C/EBP␣, respectively. Reconstitution of SWI/SNF function restores C/EBP␣-dependent proliferation arrest. Our results show that the anti-proliferation activity of C/EBP␣ critically depends on components of the SWI/SNF core complex and suggest that the functional interaction between SWI/SNF and C/EBP␣ is a prerequisite for proliferation arrest.

The pressure-induced new structures and properties of osmium hydrides were systematically explored in a wide pressure range 0−300 GPa using ab initio methods. Three stable stoichiometries, that is, OsH, OsH 3 , and OsH 6 , are predicted above 50 GPa. The above hydrides exhibit metallic character with the notable band structures exception of OsH 6 . It is interesting to note that the phase P2 1 /c of hydrogen-rich OsH 6 adopts intriguing structures with H 2 units. The electron−phonon coupling calculations indicate that the superconducting critical temperature (T c ) values of Fm-3m-OsH is 2.

The phase stability, mechanical properties and metallic properties of tantalum nitrides are extensively studied by means of first principles calculations. The relationship between nitrogen concentration and physical properties of tantalum nitrides has been systematically investigated. With the nitrogen concentration increasing, it is found that the feature of covalent bonding enhances and the directionality of the covalent bonding and hardness of tantalum nitrides reduce. While these make the ductility of tantalum nitrides improve with the nitrogen concentration increasing. The intensity of metallic properties of tantalum nitrides can be effectively adjusted by controlling the nitrogen concentration and pressure.When the tantalum: nitrogen ratio reaches Ta : N ¼ 1 : 3, remarkable nitrogen-nitrogen bonds are found in TaN 3 . The hardness of TaN 3 abnormally increases with reference to that of the preceding composition Ta 3 N 5 -II. The potential synthesis routes of tantalum nitrides are suggested.

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The crystal structures and properties of hafnium hydride under pressure are explored using the first-principles calculations based on density function theory. The material undergoes pressure-induced structural phase transition I4/mmm→Cmma→P21/m at 180 and 250 GPa, respectively, and all of these structures are metallic. The superconducting critical temperature Tc values of I4/mmm, Cmma, and P21/m are 47–193 mK, 5.99–8.16 K and 10.62–12.8 K at 1 atm, 180 and 260 GPa, respectively. Furthermore, the bonding nature of HfH2 is investigated with the help of the electron localization function, the difference charge density and Bader charge analyses, which show that HfH2 is classified as a ionic crystal with the charges transferring from Hf atom to H.