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Considering the malicious risks associated with diverse terminals in the industrial Internet of things (IIoT), a practical Byzantine fault tolerant (PBFT) efficient consensus algorithm based on credit score and dynamic double layer (CD-PBFT) was proposed to meet the requirements of high efficiency and security fault tolerance in the consensus process. The participation of good nodes in the consensus and the removal of faulty nodes were ensured by the credit score model. The parallelism of transaction verification and read write operations was achieved through the implementation of a double layer architecture. Nodes with high credit were randomly selected as the master node by the adaptive master node algorithm, ensuring its security. Experimental results show that CD-PBFT not only can maintain the safety and liveness of the consensus algorithm but also can reduce network delay by 34.8% and increase throughput by 25.2% compared with PBFT, which meets the double requirements of efficiency and security fault tolerance.

Thrombotic disease refers to the disease caused by thrombosis and thromboembolism. In recent years, the global incidence and mortality rates of thromboembolic diseases has increased significantly, posing a serious threat to human life and health. Since ancient times, anticoagulant has been an important way to prevent and treat thrombotic diseases. However, anticoagulant tolerance and side effects have appeared in its clinical applications. Food-derived bioactive peptides have the advantages of high bioavailability and safety and are very promising in the prevention and treatment of thrombotic diseases. This paper summarizes the sources, preparation, purification, identification, anticoagulant activity and mechanisms of food-derived antithrombotic peptides in order to provide a reference for the future development of food-derived antithrombotic peptides and new anticoagulants.

To explore the changes in the viability and taste compounds of Crassostrea gigas at different circulation stages after harvesting, the oysters were sampled at different times of depuration, induced dormancy and waterless live storage for evaluation of viability changes in terms of adenosine triphosphate (ATP) related compounds, adenylate energy charge (AEC) and free amino acids and evaluation of flavor quality changes with respect to contents and taste activity values (TAV) of taste compounds. The results showed that the viability and taste compounds of C. gigas were significantly influenced by postharvest transportation and environmental stress. All viability indicators were significantly restored by 24 h depuration, with ATP, AEC and the content of total free amino acids being significantly higher than before depuration (P < 0.05), indicating that the viability reached new levels. During the process from induced dormancy to waterless live storage, more energy substances were required to maintain the balance of the organism under low temperature and hypoxia stress, so all viability indicators were significantly lower than before depuration (P < 0.05) and remained stable at a lower level. Among the taste compounds, the content of umami amino acids increased and the content of bitter amino acids decreased in C. gigas after depuration, and the content of taste amino acids decreased slowly as the waterless live storage time increased. The umami?nucleotides inosine 5’-monphosphate (IMP) and adenosine 5’-monophosphate (AMP) were accumulated throughout the circulation process (P < 0.05); the total amount of organic acids showed a fluctuant downward trend, with the amount of lactic acid being significantly higher after than before depuration (P < 0.05) and showing a decreasing trend from dormancy to the end of waterless live storage (P < 0.05), while the amounts of succinic acid and malic acid showed an increasing trend during waterless live storage (P < 0.05). The levels of Na+ and K+, which play an auxiliary role in the umami taste of C. gigas, were higher after 9 days of waterless live storage than before depuration. The total amount of taste substances did not change overall. The TAV of taste compounds showed that Asp, Glu, Arg, Ala, IMP, lactic acid, succinic acid, Na+ and K+ contributed significantly to the taste of C. gigas. In conclusion, the viability and taste substances of C. gigas can be maintained at a high level by depuration for 24 hours + gradient cooling to induce dormancy + ecological ice temperature waterless live storage for 9 days after harvesting.

This study aimed to reveal the flavor quality changes of live oysters during different steps of circulation, and optimize the management of live oyster transportation in order to improve the survival quality of oysters. The changes in the types and contents of volatile flavor compounds in Crassostrea gigas sequentially subjected to depuration, induced dormancy and simulated waterless live transportation were investigated using solid phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GC-MS). Results showed that a total of 49 volatile flavor substances were identified in live C. gigas, including aldehydes, ketones, esters, hydrocarbons, alcohols, nitrogen-containing and sulfur-containing heterocyclic compounds. Post-harvest stress had a significant impact on the flavor quality. The content of pleasant flavor compounds was significantly enhanced while the content of irritating odor substances was evidently reduced, and lipid oxidation was significantly alleviated after 24 h of depuration. Lipid oxidation in oysters was increased with waterless live transportation time, and the total amount of volatile flavor substances was slowly accumulated. Odor activity values (OAVs) showed that heptanal, nonanal, (E)-2-nonenal, 4-ethylbenzaldehyde, hexanal, (E)-2-octenal, undecanal, (E)-2-decenal, decanal, (E,E)-2,4-nonadienal and 2-pentyl furan were the key flavor substances of live C. gigas, which could be used as a reference to reflect the physiological status of live oysters. Principal component analysis (PCA) showed that the cumulative contribution of the first three principal components to total variances was 85.6%, allowing a clear distinction between the different stages of circulation. In conclusion, the vitality and flavor substances of C. gigas reach a new level after post-harvest depuration for 24 h, which is more conducive to long-term low temperature and waterless live oyster preservation. Meanwhile, the analysis of volatile components can be used as a method to identify the vitality during the circulation of live shellfish.

In order to tap the potential of high-value utilization of Chlamys nobilis, using compound protease to hydrolyze Chlamys nobilis adductor muscle, the effect of EHCA(enzymatic hydrolysate of Chlamys nobilis adductor muscle) on the activity of α-glucosidase and the scavenging ability of DPPH free radicals was explored. The fasting blood glucose concentration, serum insulin content, liver malondialdehyde and superoxide dismutase content were used as indicators to evaluate the auxiliary hypoglycemic function and antioxidant activity of EHCA in normal mice. The results showed that EHCA had good a-glucosidase inhibitory activity, and its DPPH free radical scavenging ability increased with the concentration of the enzymatic hydrolysate. The results of animal experiments showed that a certain concentration of EHCA could enhance the glucose tolerance of mice, significantly reduced the liver malondialdehyde and increase the activity of superoxide dismutase. In conclusion, the compound protease can effectively enzymolyze the adductor muscle of Chlamys nobilis, and its enzymatic hydrolysate has good α-glucosidase inhibitory activity and antioxidant activity with a certain auxiliary hypoglycemic effect. The results may provide a theoretical basis for the development of auxiliary hypoglycemic marine functional foods. [ABSTRACT FROM AUTHOR]

In order to meet the requirements of virtual and real interaction, real-time response and precise control in the actual flight process of UAV, taking the flight process of quadrotor UAV as the mission requirement, this paper puts forward the flight process simulation research of quadrotor UAV based on digital twin technology. The quadrotor UAV flight digital twin system architecture is built, the flow direction and function of digital twin simulation data is analyzed, and the function and significance of quadrotor UAV flight digital twin system is introduced. The digital twin model of quadrotor UAV is constructed from the four aspects of geometry, physics, behavior and rules. Finally, a case study of the cruise process of quadrotor UAV is carried out, through the analysis of various parameters in the simulation case, the interaction between virtual and real UAVs is investigated, the accuracy of the digital twin model is proved, and the feasibility of the flight digital twin system of quadrotor UAV is verified. [ABSTRACT FROM AUTHOR]