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Finding high‐temperature superconductivity in light‐weight element containing compounds at atmosphere pressure is currently a research hotspot but has not been reached yet. Here it is proposed that hard or superhard materials can be promising candidates to possess the desirable high‐temperature superconductivity. By studying the electronic structures and superconducting properties of H and Li doped c‐BN within the framework of the first‐principles, it is demonstrated that the doped c‐BN are indeed good superconductors at ambient pressure after undergoing the phase transition from the insulating to metallic behavior, though holding different nature of metallization. Li doped c‐BN is predicted to exhibit the superconducting transition temperature of ≈58 K, while H doped c‐BN has stronger electron–phonon interaction and possesses a higher transition temperature of 122 K. These results and findings thus point out a new direction for exploring the ambient‐pressure higher‐temperature superconductivity in hard or superhard materials. [ABSTRACT FROM AUTHOR]

The reactivity between NaH and H2 has been investigated through a series of high-temperature experiments up to pressures of 78 GPa in diamond anvil cells combined with first principles calculations. Powder X-ray diffraction measurements show that heating NaH in an excess of H2 to temperatures around 2000 K above 27 GPa yields sodium trihydride (NaH3), which adopts an orthorhombic structure (space group Cmcm). Raman spectroscopy measurements indicate that NaH3 hosts quasi-molecular hydrogen (H2-) within a NaH lattice, with the H2- stretching mode downshifted compared to pure H2 (Av 120 cm-1 at 50 GPa). NaH3 is stable under room temperature compression to at least 78 GPa, and exhibits remarkable P-T stability, decomposing at pressures below 18 GPa. Contrary to previous experimental and theoretical studies, heating NaH (or NaH3) in excess H2 between 27 and 75 GPa does not promote further hydrogenation to form sodium polyhydrides other than NaH3. [ABSTRACT FROM AUTHOR]

In individuals with underlying chronic liver disease (CLD), hepatitis E virus (HEV) infection is a potential trigger of acute‐on‐chronic liver failure. In this systematic review, seven electronic databases were searched. Pooled incidence rates with 95% confidence intervals (95% CIs) were calculated by the Freeman–Tukey double arcsine transformation method. The association between death or liver failure and HEV superinfection in CLD patients was estimated by the odds ratios (OR) with a 95% CI. A total of 18 studies from 5 countries were eligible for systematic review. The prevalence of acute HEV infection in hospitalized CLD patients with clinical manifestations of hepatitis was 13.6%, which was significantly higher than that in CLD patients from the community (pooled prevalence 1.1%). The overall rates of liver failure and mortality in CLD patients with HEV superinfection were 35.8% (95% CI: 26.7%–45.6%) and 14.3% (95% CI: 10.6%–18.5%), respectively, with the rates in cirrhotic patients being approximately 2‐fold and 4‐fold higher than those in noncirrhotic patients, respectively. The risks of liver failure (OR = 5.5, 95% CI: 1.5–20.1) and mortality (OR = 5.0, 95% CI: 1.9–13.3) were significantly higher in CLD patients with HEV superinfection than in those without HEV superinfection. HEV testing in hospitalized CLD patients is necessary due to the high prevalence of HEV infection observed in hospitalized CLD patients. HEV superinfection could accelerate disease progression in patients with underlying CLD and increase mortality in these patients. HEV vaccination is appropriate for patients with pre‐existing CLD. [ABSTRACT FROM AUTHOR]

Clathrate hydrideFm3-m-LaH 10 has been proven as the most extraordinary superconductor with the critical temperature T c above 250 K upon compression of hundreds of GPa in recent years. A general hope is to reduce the stabilization pressure and maintain the high T c value of the specific phase in LaH 10 . However, strong structural instability distortsFm3-mstructure and leads to a rapid decrease of T c at low pressures. Here, we investigate the phase stability and superconducting behaviors ofFm3-m-LaH 10 with enhanced chemical pre-compression through partly replacing La by Ce atoms from both experiments and calculations. For explicitly characterizing the synthesized hydride, we choose lanthanum-cerium alloy with stoichiometry composition of 1:1. X-ray diffraction and Raman scattering measurements reveal the stabilization ofFm3-m-La 0.5 Ce 0.5 H 10 in the pressure range of 140-160 GPa. Superconductivity with T c of 175 ± 2 K at 155 GPa is confirmed with the observation of the zero-resistivity state and supported by the theoretical calculations. These findings provide applicability in the future explorations for a large variety of hydrogen-rich hydrides., (© 2023 IOP Publishing Ltd.)