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Obtaining discriminative joint features is crucial for skeleton-based human action recognition. Current models mainly focus on the research of skeleton topology encoding. However, their predefined topology is the same and fixed for all action samples, making it challenging to obtain discriminative joint features. Although some studies have considered the complex non-natural connection relationships between joints, the existing methods cannot fully capture this complexity by using high-order adjacency matrices or adding trainable parameters and instead increase the computation parameters. Therefore, this study constructs a novel adaptive channel-enhanced graph convolution (ACE-GCN) model for human action recognition. The model generates similar and affinity attention maps by encoding channel attention in the input features. These maps are complementarily applied to the input feature map and graph topology, which can realize the refinement of joint features and construct an adaptive and non-shared channel-based adjacency matrix. This method of constructing the adjacency matrix improves the model's capacity to capture intricate non-natural connections between joints, prevents the accumulation of unnecessary information, and minimizes the number of computational parameters. In addition, integrating the Edgeconv module into a multi-branch aggregation improves the model's ability to aggregate different scale and temporal features. Ultimately, comprehensive experiments were carried out on NTU-RGB+D 60 and NTU-RGB+D 120, which are two substantial datasets. On the NTU RGB+D 60 dataset, the accuracy of human action recognition was 92% (X-Sub) and 96.3% (X-View). The model achieved an accuracy of 96.6% on the NW-UCLA dataset. The experimental results confirm that the ACE-GCN exhibits superior recognition accuracy and lower computing complexity compared to current methodologies. [ABSTRACT FROM AUTHOR]

Millimeter‐wave dielectric characteristrics of Sr1−xCaxSmAlO4 ceramics were investigated together with their structures. The solid solution in the space group I4/mmm was determined in the entire composition range, and the excellent microwave dielectric characteristics were not only obtained in the centimeter‐wave range but also in the millimeter‐wave range. The dielectric constant εr indicated a slight decrease from 19.5, and the significantly improved Q×f value was achieved, while the temperature coefficient of resonant frequency τf became more negative (from −3.4 to −12 ppm/°C) with increasing x. Q×f value showed apparent increase with increasing frequency, and the Q×f value at 28 GHz was improved from 88 000 to 160000 GHz with increasing x. The best combination of millimeter‐wave dielectric characteristics was achieved at x = 0.6: εr = 19, Q×f = 143 300 GHz (at 27.3 GHz), and τf = −9.3 ppm/°C. The present ceramics could be expected as the promising candidates as millimeter‐wave dielectric ceramics. [ABSTRACT FROM AUTHOR]

Spodoptera frugiperda poses a severe threat to crops, causing substantial economic losses. The increased use of chemical pesticides has led to resistance in S. frugiperda populations. Micro ribonucleic acids (MicroRNAs or miRNAs) are pivotal in insect growth and development. This study aims to identify miRNAs across different developmental stages of S. frugiperda to explore differential expression and predict target gene functions. High-throughput sequencing of miRNAs was conducted on eggs, 3rd instar larvae, pupae, and adults. Bioinformatics analyses identified differentially expressed miRNAs specifically in larvae, with candidate miRNAs screened to predict target genes, particularly those involved in detoxification pathways. A total of 184 known miRNAs and 209 novel miRNAs were identified across stages. Comparative analysis revealed 54, 15, and 18 miRNAs differentially expressed in larvae, compared to egg, pupa, and adult stages, respectively. Eight miRNAs showed significant differential expression across stages, validated by quantitative reverse transcription PCR (qRT-PCR). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses predicted target genes' functions, identifying eight differentially expressed miRNAs targeting 10 gene families associated with detoxification metabolism, including P450s, glutathione S-transferase (GSTs), ATP-binding cassette (ABC) transporters, and sodium channels. These findings elucidate the species-specific miRNA profiles and regulatory mechanisms of detoxification-related genes in S. frugiperda larvae, offering insights and strategies for effectively managing this pest. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) chiroptical response has been less explored because it is challenging to achieve both chirality and NIR absorption/emission. Herein, we describe the design of heterohelicene‐type β‐isoindigo‐based boron‐dipyrromethene (BODIPY) analogs (β‐IBs), which shift the absorption peak to 800 nm and produce significant Cotton effects (127.8 M−1 cm−1) and absorbance dissymmetry factors (|gabs| = 3.5 × 10−3). The luminescence dissymmetry factor (glum) and circularly polarized luminescence (CPL) brightness (BCPL) of up to 1.24 × 10−3 and 1.78 M−1 cm−1 were realized beyond 800 nm. These β‐IBs are the first examples of helicene‐type compounds with the highest gabs in the NIR region and CPL beyond 800 nm. Theoretical calculations demonstrate that the strong chiroptical activities are triggered by their large transition magnetic dipole moments. This study not only provides a new approach to the synthesis of a larger variety of unprecedented helicene‐type BODIPY analogs but also demonstrates excellent NIR chiroptical properties. [ABSTRACT FROM AUTHOR]

Coordination chemistry driven by aurophilic interactions has generated numerous unique supramolecular architectures with tunable structures and innovative functions. In this work, a dimeric cluster-based capsule [C1]2·6PF6− ([(dppmAu2)3L1]2·6PF6−) with a dynamic cavity was self-assembled. The dppmAu2Cl2 dinuclear gold(I) complex was used as the coordination corner and the K3L1 (1, 3, 5-tri(1-bicarbodithiolate piperazinyl)-2,4,6-triethylbenzene potassium salt) tripodal cavitand acted as the organic linker in a multiple-component modular synthesis strategy. A tetranuclear gold(I) corner with a continuous AuI⋯AuI bonding motif was formed during the self-assembly and crystallization process of a [Au6L1]-type semispherical monomeric cluster that was spontaneously aggregated into a [Au6L1]2-type dimeric capsule. The AuI⋯AuI coupling molecular capsule exhibited excellent photophysical properties and electron–hole separation ability. Accordingly, the photocatalytic performance for the benzylamine oxidation coupling reaction was outstanding. For ten aromatic amine substrates, the catalytic yield reached 88–96% under irradiation. In addition, the recycled catalytic yield remained above 86% after three runs due to the high chemical stability and tolerance of the [C1]2·6PF6− cluster catalyst. In the photocatalytic mechanism, the primary amines formed holes, thereby triggering amine substrate oxidation, reactive oxygen species (ROS)-induced C–N bond activation, and imine condensation. Here, the formation of the intermediate benzaldehyde was detected using real-time 1H-NMR monitoring and electrospray ionization mass spectroscopy (MS), and then further confirmed by density functional theory (DFT) calculations. This dynamic gold(I) cluster-based capsule can potentially be utilized as a photocatalyst via selective host-guest recognition associated with cooperative multi-metal aurophilic interaction. [ABSTRACT FROM AUTHOR]