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Very recently, half-hydrogenated germanene has been achieved in an experiment. In this paper, we investigate the effects of tetracyanoquinodimethane (TCNQ) molecular adsorption and strain on the electronic properties of half-hydrogenated germanene through first-principles. As an electron-acceptor molecule, TCNQ is exploited to non-covalently functionalize the half-hydrogenated germanene. However, this physical adsorption induces a ferromagnetic semiconductor–metal transition in half-hydrogenated germanene due to charge transfer from the substrate to the TCNQ molecule. More importantly, the superstructure of half-hydrogenated germanene/TCNQ is extremely sensitive to biaxial tensile strain. Under the biaxial tensile strain of 0.25%, the ferromagnetic semiconductor–metal transition induced by molecular adsorption can surprisingly be overturned. Meanwhile, a strong p-type doping is exhibited. Remarkably, it would return from a ferromagnetic semiconductor to a metal again when the biaxial tensile strain increases to 1.5%. Our analysis based on the structural and electronic properties of half-hydrogenated germanene/TCNQ indicates that such metal–semiconductor–metal transition in half-hydrogenated germanene/TCNQ under biaxial tensile strain may originate from the strong local deformation, resulting in the energy of the valence band maximum decreasing below or increasing above the Fermi level. [ABSTRACT FROM AUTHOR]

Fully-hydrogenated germanene, named germanane, represents a new nanostructured material for a variety of potential applications, such as electronics and optoelectronics. However, a critical requirement for developing practical and reliable electronic devices based on germanane consists of achieving a flexibly controllable charge carrier and doping level. Different to the conventional doping methods such as ion implantation and diffusion, by first-principles calculations we demonstrate that tetracyanobenzene (TCNB) molecular adsorption could introduce effective p-type doping in germanane due to the combination of germanane with electroactive acceptor molecule TCNB. The corresponding energy difference between the empty band minimum of the dopant and the valence band maximum for electron excitation is 0.173 eV. More importantly, this nondestructive p-type doping could be linearly tuned under an external E-field. Analysis of charge transfer by means of the equivalent capacitor model and the shift of energy levels in the superstructure of germanane/TCNB further reveals that the superposition of the external E-field and molecular adsorption-induced internal E-field plays a key role in the charge transfer between TCNB and germanane, especially in achieving a controllable p-type molecular doping level in germanane. Such convenient and flexible E-field-engineering of p-type molecular doping in germanane would be very helpful for potential applications of germanane-based electronic and optoelectronic devices in the future. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Long noncoding RNAs (lncRNAs) have been reported to be vital in tumor progression. Hepatocellular carcinoma (HCC) is a common type of fatal primary liver cancers worldwide. This study aims to determine whether lncRNA SNHG7 (small nucleolar RNA host gene 7) functions in the metastasis of HCC. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was conducted to detect the SNHG7 expression in HCC cells and tissue samples. Moreover, function assays were performed in vitro to identify the role of SNHG7 in metastasis of HCC cells. Western blot assay was used to explore the possible mechanism. RESULTS: SNHG7 expression was remarkably higher in HCC tissues than that in adjacent tissues. Moreover, HCC migration and invasion were suppressed after silence of SNHG7 in HCC cells. Moreover, after silence of SNHG7, RBM5 was upregulated in HCC cells. Besides, the expression of RBM5 in tumor tissues was negatively correlated to the expression of SNHG7. CONCLUSIONS: Our study suggests that SNHG7 could promote cell invasion and migration in HCC cells through downregulating RBM5, which may offer a new therapeutic intervention for HCC patients. [ABSTRACT FROM AUTHOR]

The site preference of Re in NiAl was studied using first-principles calculations. The calculation of formation energies of the NiAl alloys indicated the site preference of Re on the Ni sites. The valence band structures of the NiAl alloys were investigated by photoelectron spectroscopy. The valence band spectra of the NiAl with Re shifted away from the Fermi energy level so that the Ni d-band centroid moved to a higher energy by 0.25 eV as Re was added. Such a shift could be attributed to the Ni-Re interaction, which was supported by the photoelectron spectroscopy measurement. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Long noncoding RNA SNHG7 represses the expression of RBM5 to strengthen metastasis of hepatocellular carcinoma" which appeared in the 2020 issue.