Enhanced breakdown strength and energy storage density of AgNbO_(3)ceramics via tape casting

Antiferroelectric materials are promising candidates for energy-storage applications due to their double hysteresis loops,which can deliver high power density.Among the antiferroelectric materials,AgNbO_(3)is proved attractive due to its environmental-friendliness and high potential for achieving excellent energy storage performance.However,the recoverable energy storage density of AgNbO_(3)ceramics is limited by their relatively low breakdown strength.Herein,the breakdown strength of the pure AgNbO_(3)ceramics prepared using the tape casting method is enhanced to 307 kV·cm^(-1),which is,to the best of our knowledge,among the highest values reported for pure AgNbO-3bulk ceramics.The high breakdown strength may be due to its dense microstructure and good crystallinity obtained by the tape casting method and the optimized sintering temperature.Owing to its enhanced breakdown strength,AgNbO_(3)ceramics show high recoverable energy storage density of 2.8 J·cm^(-3).These results have led to the development of lead-free antiferroelectric materials and devices with high energy storage density.

The Splicing Factor PRP31 Is Involved in Transcriptional Gene Silencing and Stress Response in Arabidopsis

Although DNA methylation is known to play an important role in the silencing of transposable elements （TEs） and introduced transgenes, the mechanisms that generate DNA methylation-independent transcrip- tional silencing are poorly understood. Previous studies suggest that RNA-directed DNA methylation （RdDM） is required for the silencing of the RD29A-LUC transgene in the Arabidopsis rosl mutant back- ground with defective DNA demethylase. Loss of function of ARGONAUTE 4 （AGO4） gene, which encodes a core RdDM component, partially released the silencing of RD29A-LUC in the rosl/ago4 double mutant plants. A forward genetic screen was performed to identify the mutants with elevated RD29A-LUC trans- gene expression in the rosl/ago4 mutant background. We identified a mutation in the homologous gene of PRP31, which encodes a conserved pre-mRNA splicing factor that regulates the formation of the U4/ U6.U5 snRNP complex in fungi and animals. We previously demonstrated that the splicing factors ZOP1 and STA1 contribute to transcriptional gene silencing. Here, we reveal that Arabidopsis PRP31 associates with ZOP1, STA1, and several other splicing-related proteins, suggesting that these splicing factors are both physically and functionally connected. We show that Arabidopsis PRP31 participates in transcrip- tional gene silencing. Moreover, we report that PRP31, STA1, and ZOP1 are required for development and stress response. Under cold stress, PRP31 is not only necessary for pre-mRNA splicing but also for regulation of cold-responsive gene expression. Our results suggest that the splicing machinery has multiple functions including pre-mRNA splicing, gene regulation, transcriptional gene silencing, and stress response.