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Civil aviation transportation equipment is more convenient and faster than other transportation tools and is an essential part of intelligent transportation. It is significant to study the reliability of positioning information and enhance traffic safety. Advanced receiver autonomous integrity monitoring (ARAIM) can provide vertical guidance during the different navigation stages in civil aviation fields. The traditional multiple hypothesis solution separation (MHSS) algorithm distributes the probability of hazardous misleading information (PHMI) and probability of false alarm (PFA) uniformly over all visible satellites resulting in reduced global availability of ARAIM. Aiming at this problem, we proposed an adaptive simulated annealing particle swarm optimization (ASAPSO) algorithm to redistribute integrity and continuity risks and establish a protection level optimization model. Based on the real BeiDou navigation satellite system/global positioning system (BDS/GPS) data, the experimental results show that the optimized algorithm can reduce the vertical protection level (VPL), and the ARAIM global availability of BDS/GPS is improved by 1.73%∼2.73%. The optimized algorithm can improve the availability of integrity monitoring at different stages of the navigation system and provide a basis for ensuring the reliability of the positioning results., Author(s): Ershen Wang [1,2]; Xiaozhu Shi [1,3]; Xidan Deng [2]; Jing Gao (corresponding author) [4]; Wei Zhang [1,3]; Huan Wang [2]; Song Xu [2] 1. Introduction The BDS-3 satellite navigation [...]

Bone marrow mesenchymal stem cells (BMSCs) have been identified as a potential therapeutic approach to immune-related diseases. Here, we show that BMSC-derived exosomes promote FOXP3 expression and induce the conversion of CD4+ T cells into CD4+CD25+FOXP3+ Treg cells, which is significant for immunosuppressive activity. We found that miR-181a-5p is upregulated in BMSC-derived exosomes and can be transferred to CD4+ T cells. In CD4+ cells, miR-181a directly targets SIRT1 and suppresses its expression. Moreover, downregulated SIRT1 enhances FOXP3 via protein acetylation. In conclusion, our data demonstrated that BMSC-derived exosomal miR-181a is critical in the maintenance of immune tolerance. Furthermore, our results reveal that BMSC-derived exosomal miR-181a induces the production of CD4+CD25+FOXP3+ Treg cells via SIRT1/acetylation/FOXP3. [ABSTRACT FROM AUTHOR]

This article proposes an efficient XOR-based visual cryptography scheme with lossless reconfigurable algorithms, which includes an encryption and a decryption schemes for gray-scale and color secret images. The encryption scheme aims to encrypt secret images by mapping them to several shared images that do not suffer any pixel expansion problem and do not reveal any information of the secret images by considering a random column selection algorithm based on the 0-mapping and 1-mapping matrices, where the two matrices are dynamically generated in the encryption scheme. Moreover, the proposed decryption scheme can reconstruct the secret images with only a series of XOR operations. The reconstructed images do not suffer any contrast distortion and pixel expansion problems comparing with their original secret images. Finally, the proposed two schemes are illustrated with the practical examples. [ABSTRACT FROM AUTHOR]

Background. Mongolian medicine is a systematic theoretical system, which is based on the balance among Heyi, Xila, and Badagan. However, the underlying mechanisms remain unclear. This study aimed to explore the characteristics of intestinal microbiota and metabolites in different rat models of Mongolian medicine. Methods. After establishing rat models of Heyi, Xila, and Badagan, we integrated 16S rRNA gene sequencing and metabolomics. Results. Heyi, Xila, and Badagan rats had significantly altered intestinal microbial composition compared with rats in the MCK group. They showed 11, 18, and 8 significantly differential bacterial biomarkers and 22, 11, and 15 differential metabolites, respectively. The glucosinolate biosynthesis pathway was enriched only in Heyi rats; the biosynthesis of phenylpropanoids pathway and phenylpropanoid biosynthesis pathway were enriched only in Xila rats; the isoflavonoid biosynthesis pathway, the glycine, serine, and threonine metabolism pathway, and the arginine and proline metabolism pathway were enriched only in Badagan rats. Conclusions. The intestinal microbiota, metabolites, and metabolic pathways significantly differed among Heyi, Xila, and Badagan rats compared with control group rats. [ABSTRACT FROM AUTHOR]