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Achieving excellent pyroelectric performance remains a challenge for lead‐free piezoelectric ceramics. To meet the requirements of both an enhanced pyroelectric coefficient at room temperature and good thermal stability during the encapsulation of pyroelectric devices, (1–x)K0.48Na0.52NbO3–xBi0.5Ag0.5ZrO3–0.2%Fe2O3 (KNN–BAZ–Fe) lead‐free ferroelectric ceramics with high Curie temperatures were prepared to obtain improved pyroelectric performance via the coexistence of multiple symmetries. The variation of BAZ content led to the formation of rhombohedral–orthorhombic–tetragonal phase boundary and promoted grain growth, resulting in the best pyroelectric coefficient (p = 5.09 × 10−4 C m−2°C−1) and enhanced figures of merit (Fi = 0.2084 × 10−9 (m V−1), Fv = 0.0142 m2 C−1, Fd = 0.0947 × 10−4 Pa−1/2, and Fe = 17.66 J m−3 K−2) for infrared (IR) detection when x = 0.05. The room‐temperature pyroelectric coefficient obtained in this study is approximately four times that of the pure KNN ceramic and is the maximum value reported for niobate‐based piezoelectric ceramics. Moreover, compared with the poor thermal stability of barium titanate‐ and bismuth sodium titanate‐based ceramics because of their ultralow Curie temperature or thermal depolarization temperature, the ceramics investigated here exhibit much better thermal stability because of their high Curie temperature (TC > 300°C) and diffused phase‐transition behavior, making them more adaptable for practical applications. These results suggest that KNN–xBAZ–Fe ceramics are attractive candidates for applications in the field of IR sensors. [ABSTRACT FROM AUTHOR]

Objective: This study explored and analyzed the effects of targeted regulation of LATS2 by LncRNA BCAR4 on the proliferation, migration and apoptosis of hepatocellular carcinoma (HCC)., Method: We detected the expression of LncRNA, BCAR4 and LATS2 mRNA in liver hepatocellular carcinoma HepG2 cells and normal hepatocellular cells LO2 by RT-PCR. HepG2 cells were divided into BCAR4-siRNA, NC-siRNA and control groups. We detected the targeted regulation of LncRNA BCAR4 on LATS2 by luciferase gene assay, and measured the proliferation, migration and apoptosis of cells in each group by RT-PCR, MTT, Transwell and flow cytometry, respectively., Results: The relative expression of LncRNA BCAR4 in HepG2 cells was critically higher than that in LO2 cells ( P<0.05 ), while LATS2 mRNA in HepG2 cells was significantly less than that in LO2 cells ( P<0.05 ). Compared with NC siRNA group, the content of luciferase in BCAR4 siRNA group was much higher ( P<0.05 ); The relative expression of LncRNA BCAR4 in BCAR4 siRNA group decreased dramatically than that in NC-siRNA and control group ( P<0.05 ), and the relative expression of LATS2 mRNA increased remarkably than that in NC-siRNA group and control group ( P<0.05 ). The OD value of BCAR4 siRNA group was dramatically higher than that of NC-siRNA group and control group after 48 h and 72 h culture (P<0.05). The quantity of invaded cells in BCAR4 siRNA group was markedly less than that in NC-SIRNA group and control group ( P<0.05 ). Cell apoptosis rate in BCAR4-siRNA group was significantly higher than that of NC-siRNA group and control group ( P<0.05 )., Conclusion: LncRNA BCAR4 can regulate the LATS2 expression, and inhibiting the expression of LncRNA BCAR4 can inhibit proliferation, invasion of HepG2 cells and induce its apoptosis, which finding provides a certain reference for the targeted therapy of liver cancer., Competing Interests: None., (AJTR Copyright © 2021.)