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The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Omicron variant is undergoing continuous evolution and convergent mutation. These new subvariants are raising concerns that they may evade neutralizing monoclonal antibodies (mAbs). We investigated the serum neutralization efficacy of Evusheld (cilgavimab and tixagevimab) against SARS‐CoV‐2 Omicron BA.2, BA.2.75, BA.2.76, BA.5, BF.7, BQ.1.1, and XBB.1.5. A total of 90 serum samples from healthy individuals were collected in Shanghai. Anti‐RBD antibodies were measured and symptoms of infection with COVID‐19 were compared among those individuals. The neutralizing activity of serum against Omicron variants was analyzed by pseudovirus neutralization assays in 22 samples. Evusheld retained neutralizing activity against BA.2, BA.2.75, and BA.5, albeit with somewhat reduced titers. However, the neutralizing activity of Evusheld against BA.2.76, BF.7, BQ.1.1, and XBB.1.5 significantly decreased, with XBB.1.5 showing the greatest escape activity among the subvariants. We also observed that Evusheld recipients displayed elevated antibody levels in their serum, which efficiently neutralized the original variant, and exhibited different characteristics of infection than those who did not receive Evusheld. The mAb has partial neutralization activity against Omicron sublineages. However, the increasing doses of mAb and a larger size of population should be further investigated. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) MoSi2N4 is a newly created material that has superstability and ultrahigh carrier mobility. Besides, the hydrogen evolution reaction activity was proved excellent by doping transition metal (TM) atoms and introducing N vacancies. But, the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) of 2D MoSi2N4 is unclear even. We have explored the electrocatalytic properties (OER/ORR) of MoSi2N4 by introducing Si vacancies and attaching various TM atoms. The structure and optoelectronic characteristics of MoSi2N4 have been researched in detail using density functional theory calculations. By analyzing the density of states, the free energy change diagram and contour maps of TM@VSi-MoSiN, the results show that Co@VSi-MoSiN has the lowest OER overpotential (0.53 V) among all samples. Additionally, the d-band center is used to explain the electrocatalytic origin of the OER and ORR of TM@VSi-MoSiN. Our discoveries expand the 2D TM@VSi-MoSiN applicability in the realm of catalysis. [ABSTRACT FROM AUTHOR]

Background: Bladder cancer (BLCA) is one of the most diagnosed cancers in humans worldwide. Recently, immunotherapy has become a main treatment option for BC. However, most BLCA patients do not respond to immune checkpoint inhibitors or relapse after immunotherapy. Therefore, it is very important to identify novel biomarkers for the prediction of immunotherapy response in B patients. Methods: Pancancer single‐cell RNA sequencing (scRNA‐seq) data were used to identify the clusters of CD4+ T cells in the tumour microenvironment (TME). The clinical significance of key CD4+ T‐cell clusters was evaluated based on the survival data of two independent immunotherapy bladder cancer (BLCA) cohorts. We also investigated the function of key clusters of CD4+ T cell in the TME of BC cells in vitro. Results: This study identified two novel exhausted CD4+ T‐cell subpopulations with the expression of PD1hi CD200hi or PD1hi CD200low in BC patients. Moreover, BLCA patients with a high level of PD1hi CD200hi CD4+ exhausted T cell showed immunotherapy resistance. Cell function analysis demonstrated that PD1hi CD200hi CD4+ exhausted T cell can promote epithelial–mesenchymal transition (EMT) and angiogenesis in BLCA cells. In addition, PD1hi CD200hi CD4+ exhausted T cells were shown to communicate with malignant BLCA cells through the GAS6–AXL axis. Finally, we also found that GAS6 expression is upregulated in B cells by METTL3‐mediated m6A modification. Conclusions: PD1hi CD200hi CD4+ exhausted T cell may serve as a novel biomarker for poor prognosis and immunotherapy resistance in B. Targeted inhibitors of PD1hi CD200hi CD4+ exhausted T cells may help improve the efficacy of immunotherapy. [ABSTRACT FROM AUTHOR]

High-entropy oxides receive significant attention owing to their "four effects". However, they still suffer from harsh construction conditions such as high temperature and high pressure and present a block-like structure. Herein, in this work, Ni-Mn-Cu-Co-Fe-Al high-entropy layered oxides (HELOs) with a layered nanosheet structure were constructed by a simple pathway of topological transformation under relatively low temperature (300 °C) with six-membered Ni-Mn-Cu-Co-Fe-Al layered double hydroxides (LDHs) precursors, which exhibited an outstanding activity and excellent selectivity for CO2 photoelectroreduction (obtaining the highest carbon monoxide yield of 909.55 µmol·g−1·h−1 under −0.8 V vs. reversible hydrogen electrode (RHE), which is almost twice that of pure electrocatalysis). In addition, the charging voltage of a photo-assisted Zn-CO2 battery with HELOs as electrode was reduced from 2.62 to 2.40 V; the discharging voltage of the battery was increased from 0.51 to 0.59 V with the assistance of illumination. The improvement of round-trip efficiency of the battery indicates that light played a positive role in both the charging and discharging processes. This study not only lays an important foundation for the development of high-entropy oxides but also expands their application in the field of photoelectrochemistry. [ABSTRACT FROM AUTHOR]

WC-Co cemented carbide has been widely used as cutting tool materials under cooling conditions. However, WC-Co cemented carbide has low high temperature hardness and poor oxidation resistance at high temperature, which limits its application in the field of high-speed machining. New WC-Al2O3 composite tool materials with high hardness and excellent oxidation resistance at high temperature were fabricated by vacuum hot pressing sintering process at 1450 °C. The mechanical properties of WC-Al2O3 composite tool materials with different Al2O3 content were studied at room and high temperature, combined with the microstructure analysis by XRD\SEM\EDS. It was found that WA5 (5 wt.% Al2O3) had the best comprehensive mechanical properties at room temperature, but its performance at high temperature was inferior to WA20 (20 wt.% Al2O3). The Vickers hardness of WA20 was 21.3 ± 0.19 GPa at 600 °C, which was higher than WA0 (3.44 ± 0.24 GPa) and WA5 (4.4 ± 0.08 GPa) at 600 °C. The oxidation experiment showed that the weight gain of WA20 at high temperature (700 °C and above) was significantly lower than that of WA0 (0 wt.% Al2O3) and WA5, which was due to the good high temperature oxidation resistance of Al2O3. In general, WA20 had good high temperature mechanical properties and better high temperature oxidation resistance, which was suitable for high-speed cutting tool. [ABSTRACT FROM AUTHOR]