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Although certain efforts were paid to the effect of K/Na ratio on the phase structure and piezoelectric properties of potassium sodium niobate {(K, Na)NbO3, KNN}‐based ceramics, insufficient attention was given to the local structure and ferroelectric domains, hindering the further understanding of physical mechanisms. Herein, we studied the effect of the K/Na ratio on KNN‐based ceramics with multi‐phase coexistence from multiscale structure. High Na+ content leads to local stress heterogeneity and retains large ferroelectric domains, while high K+ content rotates the NbO6 octahedron and results in local polarity heterogeneity and distinct dielectric relaxational behavior, consequently fragmenting ferroelectric domains. The improved piezoelectricity is obtained at the equal K/Na ratio and originates from the balanced local polarity and stress heterogeneities. Therefore, an appropriate K/Na ratio should be fully considered when designing compositions with the purpose of improving performance of KNN‐based ceramics in the future. [ABSTRACT FROM AUTHOR]

Breast cancer is a heterogeneous disease and can be divided into several subtypes with unique prognostic and molecular characteristics. The classification of breast cancer subtypes plays an important role in the precision treatment and prognosis of breast cancer. Benefitting from the relation-aware ability of a graph convolution network (GCN), we present a multi-omics integrative method, the attention-based GCN (AGCN), for breast cancer molecular subtype classification using messenger RNA expression, copy number variation and deoxyribonucleic acid methylation multi-omics data. In the extensive comparative studies, our AGCN models outperform state-of-the-art methods under different experimental conditions and both attention mechanisms and the graph convolution subnetwork play an important role in accurate cancer subtype classification. The layer-wise relevance propagation (LRP) algorithm is used for the interpretation of model decision, which can identify patient-specific important biomarkers that are reported to be related to the occurrence and development of breast cancer. Our results highlighted the effectiveness of the GCN and attention mechanisms in multi-omics integrative analysis and the implement of the LRP algorithm can provide biologically reasonable insights into model decision. [ABSTRACT FROM AUTHOR]

Although the piezo‐catalysis is promising for the environmental remediation and biomedicine, the piezo‐catalytic properties of various piezoelectric materials are limited by low carrier concentrations and mobility, and rapid electron‐hole pair recombination, and reported regulating strategies are quite complex and difficult. Herein, a new and simple strategy, integrating phase boundary engineering and defect engineering, to boost the piezo‐catalytic activity of potassium sodium niobate ((K, Na)NbO3, KNN) based materials is innovatively proposed. Tur strategy is validated by exampling 0.96(K0.48Na0.52)Nb0.955Sb0.045O3‐0.04(BixNa4‐3x)0.5ZrO3‐0.3%Fe2O3 material having phase boundary engineering and conducted the defect engineering via the high‐energy sand‐grinding. A high reaction rate constant k of 92.49 × 10−3 min−1 in the sand‐grinding sample is obtained, which is 2.40 times than that of non‐sand‐grinding one and superior to those of other representative lead‐free perovskite piezoelectric materials. Meanwhile, the sand‐grinding sample has remarkable bactericidal properties against Escherichia coli and Staphylococcus aureus. Superior piezo‐catalytic activities originate from the enhanced electron‐hole pair separation and the increased carrier concentration. This study provides a novel method for improving the piezo‐catalytic activities of lead‐free piezoelectric materials and holds great promise for harnessing natural energy and disease treatment. [ABSTRACT FROM AUTHOR]