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Existing group recommendation models often have a monotonous approach when solving user representation, and only simple social relationships between users are utilized. This makes user representation inaccurate and most models do not consider the impact of user common intention and social interaction on group preferences. As a result, recommended items are not aligned with user needs. To address these issues, a new group recommendation model based on user common intention and social interaction (GR-UCISI) is proposed. Firstly, a user intention separation model that combines user-item interaction history with social interaction is constructed. Graph neural networks are utilized to collect user-item interaction and social interaction information, and to solve user intention and item representation. Secondly, by utilizing the social network random walk algorithm and the [K-means] clustering algorithm, users can be grouped. User group, user intention and group intention aggregation process are combined to obtain group common intention representation. Finally, group common intention representation and item representation are calculated to obtain the list of recommended items for the group. This method fully considers the impact of user individuality and commonality among group members on group preferences. It also utilizes social relationships to alleviate the problem of data sparsity and improve model performance. The experimental results show that compared with the model with the best recommendation effect of nine models, on the Gowalla dataset, the Precision and NDCG of the GR-UCISI model are increased by 3.01% and 5.26% respectively, on the Yelp-2018 dataset, the Precision and NDCG of the GR-UCISI model are increased by 2.96% and 1.12% respectively.

Abstract [Objective] The study aims to identify the NAC transcription factor genes CsNAC79 and Cs- NAC9 in tea plants and analyze their expression patterns under drought, salt, high temperature, and low temperature stresses as well as ABA and GA3 treatments in order to provide references for functional analysis of CsNAC79 and CsNAC9. [Methods] CsNAC79 and CsNAC9 were amplified by RT-PCR from tea plant ‘Longjing 43’ and analyzed by bioinformatics. The expression of CsNAC79 and CsNAC9 under abiotic stresses in tea plants was analyzed by qRT-PCR. [Results] (1) CsNAC79 and CsNAC9 encoded 409 and 282 amino acids, respectively, and contain the conserved NAM domain of the NAC family at 15-150 amino acids and 11-134 amino acids, respectively. (2) CsNAC79 protein was closely related to Actinidia chinensis, Diospyros kaki, and Cynara scolymus, while CsNAC9 protein was closely related to Amygdalus persica, Litchi chinensis, and Durio zibethinus. Both of the NAC transcription factors were hydrophilic proteins without signal peptides and transmembrane structures. The promoter regions of CsNAC79 and CsNAC9 contained abiotic stress- responsive elements. Protein structure analysis showed that Cs- NAC79 and CsNAC9 proteins were mainly composed of random coils and α-helixes. (3) Expression analysis showed that CsNAC79 and CsNAC9 genes were up-regulated under different abiotic stresses. [Conclusion] The CsNAC79 and CsNAC9 genes in tea plants responded to various abiotic stresses.

The application of genetic algorithm in multi-path coverage testing is a research hotspot. In the process of iteration between the old and new populations, the old population may contain excellent individuals from other sub-populations, which are not fully utilized, resulting in resource waste. At the same time, the number of individuals in the population will be much greater than that of reachable paths, and each individual will go through a reachable path. This causes multiple individuals to pass through the same path, leading to repeated calculation of the similarity between the individual and the target path. Based on this, a multi-path coverage testing method combined with path similarity table and individual migration is proposed to improve testing efficiency. By storing the calculated path similarity value in the path similarity table, the value can be avoided from being calculated repeatedly and the testing time can be reduced. In the evolutionary process, the individual path is compared with other target paths, and if the similarity reaches the threshold, the excellent individual is migrated to the sub-population corresponding to the path, which improves the utilization rate of individuals and reduces the evolutionary generation. Experiments show that, compared with other six classic methods, the proposed method reduces the average generation time on eight programs by up to 44.64%, and the minimum is 2.64%, and the average evolution generation is reduced by up to 35.08%, and the minimum is 6.13%. Therefore, the proposed method effectively improves the test efficiency.

Renal fibrosis (RF) is an important pathogenesis for renal function deterioration in chronic kidney disease. Secreted frizzled-related protein 5 (SFRP5) is an anti-fibrotic adipokine but its direct role on RF remains unknown. It was aimed to study the protective effect of SFRP5 against RF and interference with Wnt/β‐catenin signaling pathway for the first time. First, the therapeutic efficacy of SFRP5 was evaluated by adenovirus overexpression in rats with unilateral ureteral obstruction (UUO) in vivo. Thirty-six rats were randomly divided into the sham, UUO, and SFRP5 (UUO + Ad-SFRP5) groups. Half rats in each group were selected at random for euthanasia at 7 days and the others until 14 days. Then, the transforming growth factor (TGF)-β1-induced epithelial–mesenchymal transition (EMT) was established in HK-2 cells in vitro. The cells were divided into four groups: the control group, the TGF-β1 group, the TGF-β1 + SFRP5 group, and the TGF-β1 + SFRP5 + anti-SFRP5 group. The makers of EMT and Wnt/β‐catenin pathway proteins were investigated. In the UUO model, expression of SFRP5 showed compensatory upregulation, and adenoviral-mediated SFRP5 over-expression remarkably attenuated RF, as demonstrated by maintenance of E-cadherin and suppression of α-smooth muscle actin (SMA). In vitro, SFRP5 was shown to inhibit TGF-β1-mediated positive regulation of α-SMA, fibronectin, collagen I but negative regulation of E-cadherin. Furthermore, SFRP5 abrogated activation of Wnt/β-catenin, which was the essential pathway in EMT and RF pathogenesis. The changes after a neutralizing antibody to SFRP5 confirmed the specificity of SFRP5 for inhibition. These findings suggest that SFRP5 can directly ameliorate EMT and protect against RF by inhibiting Wnt/β-catenin pathway.