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In this study, high-performance Cu–0.69Cr–0.46Co–0.34Ti (wt%) alloys with nano-precipitates and nanotwins are prepared via a two-step cryorolling and aging process. The effects of Co and Ti on the microstructural evolution as well as room-temperature and elevated-temperature mechanical behaviors are investigated. The results show that the two-step process produces high-density dislocations, profuse nanotwins into Cu–Cr–Co–Ti alloys, and enhances the mechanical properties of the latter significantly. The high-density dislocations provide sufficient diffusion paths for Cr atoms and accelerate the transformation of Cr precipitates from face-centered cubic (fcc) to body-centered cubic (bcc), resulting in the co-existence of coherent fcc Cr and incoherent bcc Cr precipitates. Dislocation strengthening and Orowan precipitation strengthening contribute significantly to the strength of the Cu–Cr–Co–Ti alloys. The tensile strength (643 MPa), hardness (201 HV), and electrical conductivity (64.75% IACS) of samples subjected to the two-step process are obtained. Results show that a CoTi compound shell inhibits the diffusion of external Cr atoms to the core and restrains the coarsening of Cr precipitates. Meanwhile, stable nano-precipitates and nanotwins decelerate the progress of recrystallization, thus improving the elevated-temperature mechanical behavior. • The refined deformation bands and twin bundles are obtained in Cu–Cr–Co–Ti alloys. • The Co and Ti elements aggregate at the periphery of Cr precipitates to restrain it coarsening. • High-density dislocations accelerate the structural transformation of Cr precipitates. • Dislocation and precipitation strengthening are dominant strengthening mechanisms. • The stable nano-precipitates and nanotwins decelerate the progress of recrystallization. [ABSTRACT FROM AUTHOR]

An outbreak of COVID-19 in Shanghai, China, in March 2022 was caused by the Omicron variant. The epidemic lasted for more than 3 months, and the cumulative number of infected people reached 626,000. We investigated the impact of clinical factors on disease outcomes in patients with COVID-19. Using a case-control study design, we examined cases from fever clinics with confirmed Omicron variant infection, analyzed their population and laboratory diagnostic characteristics, and provided theoretical support for subsequent epidemic prevention and control. Logistic regression was used to identify factors associated with infection with the Omicron variant. The results of this study show that the COVID-19 vaccine can protect against infection with the Omicron variant, and more than 50% of infected people had not been vaccinated. Compared with the epidemic in Wuhan 2 years ago, most of the patients in the hospital in the Shanghai epidemic had underlying diseases (P = 0.006). A comparison of patients infected with the Omicron variant in Shanghai and patients with other respiratory tract infections showed no significant difference in the levels of neutrophils, lymphocytes, eosinophils, white blood cells, hemoglobin, or platelets (P > 0.05). People over 60 years old and those with underlying diseases were at risk for pneumonia (OR = 14.62 (5.49-38.92), P < 0.001; OR = 5.29 (2.58-10.85), P < 0.001, respectively), but vaccination was a protective factor (OR = 0.24 (0.12-0.49), P < 0.001). In summary, vaccination has a potential effect on infection with Omicron variant strains and provides protection against pneumonia. The severity of illness caused by the Omicron variant in 2022 was significantly lower than that of the original SARS-CoV-2 variant from two years previously. [ABSTRACT FROM AUTHOR]

Background: Most of the biological functions of circular RNAs (circRNAs) and the potential underlying mechanisms in hepatocellular carcinoma (HCC) have not yet been discovered. Methods: In this study, using circRNA expression data from HCC tumor tissues and adjacent tissues from the Gene Expression Omnibus database, we identified out differentially expressed circRNAs and verified them by qRT-PCT. Functional experiments were performed to evaluate the effects of circFAM13B in HCC in vitro and in vivo. Results: We found that circFAM13B was the most significantly differentially expressed circRNA in HCC tissue. Subsequently, in vitro and in vivo studies also demonstrated that circFAM13B promoted the proliferation of HCC. Further studies revealed that circFAM13B, a sponge of miR-212, is involved in the regulation of E2F5 gene expression by competitively binding to miR-212, inhibits the activation of the P53 signalling pathway, and promotes the proliferation of HCC cells. Conclusions: Our findings revealed the mechanism underlying the regulatory role played by circFAM13B, miR-212 and E2F5 in HCC. This study provides a new theoretical basis and novel target for the clinical prevention and treatment of HCC. [ABSTRACT FROM AUTHOR]