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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]

The effects of low salinity on fatty acid and free amino acid (FAA) composition in muscles of swimming crab, Portunus trituberculatus, were investigated in this study. The swimming crabs were reared for 5 weeks under two different experimental treatments (the 12 ppt group and the 24 ppt group). Then, composition of fatty acids and free amino acids in total muscles was measured using gas chromatography–mass spectrometry (GC‐MS) with external standard method and liquid chromatography–mass spectrometer (LC‐MS) with internal standard method respectively. Results of fatty acid analysis showed that C18:1n9c, C20:5n3 (EPA) and C22:6n3 (DHA) were the dominating fatty acids in muscle tissues of P. trituberculatus. There was an extremely significant increase in contents of total fatty acids (TFA), total saturated fatty acids (SFA), total monounsaturated fatty acid (MUFA) and total polyunsaturated fatty acid (PUFA) in muscle tissues of P. trituberculatus with low salinity treatment (12 ppt) compared with those cultured in seawater (24 ppt) (p < 0.01). Results of free amino acid analysis showed that the content of total free amino acids (TFAA) significantly decreased in muscle tissues of P. trituberculatus with low salinity treatment compared with those in seawater (p < 0.05). Among all flavour‐tasting FAAs, the umami FAA content was extremely significantly higher in low salinity group compared with control group (p < 0.01); the sweetish FAA content was significantly lower in low salinity group while the bitter taste of FAA content had no significant differences between two groups. [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]

Scylla paramamosain is one of the commercially crucial marine crustaceans belonging to the genus Scylla, which is commonly distributed along the coasts of China. Proteomic data are scarce for the mud crab. Salinity is one of the ecological factors that affect S. paramamosain during overwintering. To understand the energy metabolism mechanism adapted to salinity, we analysed the proteomics of S. paramamosain hepatopancreas in response to two different salinities (4‰ and 25‰). A total of 1283 proteins were detected, of which 426 down‐regulated proteins and 83 up‐regulated proteins were associated with metabolism (p < 0.05). Among these proteins related to metabolic pathways (16 pathways), we identified angiotensin‐converting enzyme, trypsin, glutamate dehydrogenase, aminomethyl transferase, hexokinase, pyruvate kinase, glucose‐6‐phosphate dehydrogenase, L‐lactate dehydrogenase, superoxide dismutase, alkaline phosphatase, catalase and xanthine dehydrogenases. Additionally, real‐time PCR showed mRNA expression of differentially expressed genes correlated positively with their protein levels. Compared with 25‰ salinity group, 4‰ salinity group was involved in amino acid metabolism, carbohydrate metabolism, energy metabolism, lipid metabolism and inorganic ion metabolism by regulating related proteins, which made the metabolism of the overwintering S. paramamosain more vigorous in the low salt environment, and hepatopancreas consumed more energy to maintain life activities. These data are the first to reveal the molecular mechanism of overwintering S. paramamosain in response to different salinities at the protein level. The study provides important information for the aquaculture production of S. paramamosain during indoor overwintering. [ABSTRACT FROM AUTHOR]

Summary: The microstructure and behaviors of the interface layer around the nanoparticle are strongly related to the overall thermophysical properties of molten salt‐based nanofluids (MSBNFs). Understanding this link may enable the advanced heat transfer fluid (HTF) for concentrated solar power and other applications. In this study, a molecular dynamics (MD) model for solar salt (60 wt% NaNO3/40 wt% KNO3)‐SiO2 nanofluid system is developed to estimate the characteristics of the interface layer and their effects on the overall specific heat capacity (SHC) and effective thermal conductivity (ETC) of MSBNFs. The results show that the SHC and thermal conductivity (TC) of the interface layer in MSBNFs are, respectively, 1.44‐1.85 and 1.05‐1.97 times higher than those of pure solar salt. The SHC of the interface layer has a significant effect on the overall SHC of the MSBNFs, but the interface layer is not the dominant influencing factor for the ETC enhancement of MSBNFs and thus has less effect on the overall ETC. [ABSTRACT FROM AUTHOR]

Overwintering is an important part of the conservation of Scylla paramamosain, and salinity is a primary parameter affecting this species' metabolism at this particular time. We compared and analysed gene sequences responsible for the metabolism of S. paramamosain at 4‰ versus 25‰ salinities using transcriptome analysis, in order to find out the optimum salinity for S. paramamosain during overwintering. A total of 5895 genes were detected, of which 105 down‐regulated genes and 131 up‐regulated genes were associated with metabolism (p < 0.05). Among these genes related to metabolic pathways (117 pathways), we identified D‐aspartate oxidase, D‐amino acid oxidase, creatine kinase, sarcosine oxidase, citrate synthase, transferase, glycogen synthase, hexokinase, carbonic anhydrase, glutamine synthetase, V‐type H+‐transporting ATPase, 3′‐phosphoadenosine 5′‐phosphosulphate synthase, fatty acid synthase and others. Additionally, the consistency between qRT‐PCR results and transcriptome data reflected the reliability of transcriptome results in the present study. Compared with the 25‰ salinity group, the 4‰ salinity group promoted energy metabolism, amino acid metabolism, lipid metabolism and carbohydrate metabolism by regulating metabolism‐related genes, which made the overwintering S. paramamosain more active in the low‐salt environment, and hepatopancreas consumed more energy to maintain life activities. These results improve our understanding on molecular mechanisms and metabolic pathways associated with salinity changes in S. paramamosain during overwintering. The data presented in this study are also the first to reveal the molecular mechanisms of S. paramamosain during overwintering in response to different salinities at the gene level. [ABSTRACT FROM AUTHOR]