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The macroscopic properties of piezoelectric materials can be profoundly influenced by stress. In this research, thermodynamic potential parameters of K0.4Na0.6NbO3 (KNN) single crystals have been experimentally quantified to assess the effects of stress. Leveraging the Landau thermodynamic potential theory, it has been identified that the application of biaxial tensile stress causes a significant elevation in both the piezoelectric property and phase transition temperature in KNN crystals. This transition remarkably extends their working range and improves the material's applicated potential. The coherence between these computational outcomes and experimental data—from the strategic growth of KNN single crystals with internal stress—underscores the reliability of our findings (dielectric constant from 213 to 1274, TO-T from 180 to 234 °C). Additionally, theoretical calculation predicts a potential enhancement in the piezoelectric capabilities of KNN single crystals. This study provides valuable insights for the growth of high-quality piezoelectric crystals and further promotes the application of lead-free piezoelectric materials. [ABSTRACT FROM AUTHOR]

Affective brain-computer interface based on electroencephalography (EEG) is an important branch in the field of affective computing. However, the individual differences in EEG emotional data and the noisy labeling problem in the subjective feedback seriously limit the effectiveness and generalizability of existing models. To tackle these two critical issues, we propose a novel transfer learning framework with Prototypical Representation based Pairwise Learning (PR-PL). The discriminative and generalized EEG features are learned for emotion revealing across individuals and the emotion recognition task is formulated as pairwise learning for improving the model tolerance to the noisy labels. More specifically, a prototypical learning is developed to encode the inherent emotion-related semantic structure of EEG data and align the individuals’ EEG features to a shared common feature space under consideration of the feature separability of both source and target domains. Based on the aligned feature representations, pairwise learning with an adaptive pseudo labeling method is introduced to encode the proximity relationships among samples and alleviate the label noises effect on modeling. Extensive results on two benchmark databases (SEED and SEED-IV) under four different cross-validation evaluation protocols validate the model reliability and stability across subjects and sessions. Compared to the literature, the average enhancement of emotion recognition across four different evaluation protocols is 2.04% (SEED) and 2.58% (SEED-IV). [ABSTRACT FROM AUTHOR]

Thermomorphogenesis and the heat shock (HS) response are distinct thermal responses in plants that are regulated by PHYTOCHROME‐INTERACTING FACTOR 4 (PIF4) and HEAT SHOCK FACTOR A1s (HSFA1s), respectively. Little is known about whether these responses are interconnected and whether they are activated by similar mechanisms. An analysis of transcriptome dynamics in response to warm temperature (28°C) treatment revealed that 30 min of exposure activated the expression of a subset of HSFA1 target genes in Arabidopsis thaliana. Meanwhile, a loss‐of‐function HSFA1 quadruple mutant (hsfa1‐cq) was insensitive to warm temperature‐induced hypocotyl growth. In hsfa1‐cq plants grown at 28°C, the protein and transcript levels of PIF4 were greatly reduced, and the circadian rhythm of many thermomorphogenesis‐related genes (including PIF4) was disturbed. Additionally, the nuclear localization of HSFA1s and the binding of HSFA1d to the PIF4 promoter increased following warm temperature exposure, whereas PIF4 overexpression in hsfa1‐cq partially rescued the altered warm temperature‐induced hypocotyl growth of the mutant. Taken together, these results suggest that HSFA1s are required for PIF4 accumulation at a warm temperature, and they establish a central role for HSFA1s in regulating both thermomorphogenesis and HS responses in Arabidopsis. [ABSTRACT FROM AUTHOR]