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Air data computer simulation system is a platform for studying aircraft air data system. It can also replace real air data computer and can be used in the experiment of ground integrated avionics system, which greatly reduces the cost and risk of the experiment. However, when the simulation system replaces the real system, whether its reliability, integrity and other indicators can meet the requirements becomes the key to the problem. Based on computer simulation theory and simulation credibility evaluation theory, this paper designs and implements two types of atmospheric data computer simulation systems and evaluates the credibility of the simulation systems. The basic theory of computer simulation and the general process of simulation are expounded, the evaluation theory of simulation credibility is introduced, and the evaluation calculation method of simulation credibility is given. The results show that the highest reliability of the reliability evaluation using the method in this paper reaches 90%, the highest error rate is 0.06%, and the average accuracy, efficiency and complexity of the hundred experiments are 97.31% and 97.00% and 0.154%. The highest reliability of the subjective comprehensive evaluation algorithm for reliability evaluation is 65%, the highest error rate is 0.27%, and the average accuracy, efficiency and complexity of the hundred experiments are 70.59% and 69.74%, and 0.502%. Therefore, the method in this paper not only has high reliability, low error rate, but also has strong comprehensive effectiveness.

In this work, novel injectable and radiopaque calcium phosphate bone cements were prepared using zirconia short fiber as a radiopacifier. The radiopacity, setting time, injectability, anti-washout ability, microstructure, mechanical property, and the in vitro cytocompatibility of the novel cements were evaluated thoroughly. The results reveal that the incorporation of zirconia fiber significantly improves the radiopacity of bone cement while it has no significant effect on the setting time, anti-washout ability, and injectability. The cements are still injectable and show good manual operability. Moreover, the flexural strength and compressive strength of the composite bone cement with 2 wt% fibers are enhanced. Additionally, MTT results reveal that the zirconia fiber doped cements exhibit no cytotoxicity toward osteoblastic MG63 cells, and MG63 cells can adhere and proliferate well on the cements. Therefore, calcium phosphate bone cement containing zirconia fibers has the potential to be used as a bone repair material for minimally invasive surgery. [ABSTRACT FROM AUTHOR]

In this work, chopped basalt fibres were used as reinforcing and toughening phase to enhance the mechanical properties of calcium phosphate bone cement. The microstructure, mechanical properties, and cytocompatibility of the composite cement were evaluated thoroughly. The results revealed that the addition of fibres did not significantly change the cement setting process but markedly improved the toughness. The fracture work of cement with 1 wt% fibres was 10 times higher than that of the pure control due to pulling out of the fibres. Moreover, the flexural strength of composite cement was also promoted with a certain amount of fibres. Additionally, the composite cementscement showed no cytotoxicity to MG63 cells, and the osteoblasts could adhere and proliferate well on the cements. Therefore, basalt fibres could be potentially used as a reinforcing phase for calcium phosphate bone cement. [ABSTRACT FROM AUTHOR]

Reports on the discovery of early Permian reef belt in east Kunlun, north area of Qinghai-Tibet Plateau, China. Regional geology; Reef-building organisms; Classification of facies; Importance of the discovery of ancient reef in eastern Kunlun and Animaqing.

We investigated artificial radionuclides ( 239+240 Pu and 137 Cs) in surface sediments and sediment cores collected from the Bohai Bay and the tidal flat of the Liaodong Bay, China. Increasing trends for 239+240 Pu activities and 240 Pu/ 239 Pu atom ratios (˃0.18) were observed from land to sea and from north to south in the Bohai Bay. This spatial pattern implied that the scavenging process between riverine sediments and Pacific Proving Ground (PPG) source Pu transported by the currents such as Yellow Sea Warm Current had occurred in the Bohai Bay. In contrast, relatively lower 240 Pu/ 239 Pu atom ratios in the tidal flat of Liaodong Bay were due to the mixing process between more global out and less PPG source Pu. The riverine Pu contributions to the total global fallout Pu in the Haihe River (32.8%) were much lower than those in the Yangtze River estuary (77%-80%), indicating better soil conservation in the Haihe River Catchment., (Copyright © 2018. Published by Elsevier Ltd.)

The objective of the study was to clone avian beta-defensin (AvBD) 5 gene from pigeon bone marrow tissues and liver tissues, to express the recombinant AvBD5 protein in E. coli, and to determine its antimicrobial activity. The mRNA of duck AvBD5 was cloned from pigeon bone marrow tissues and liver tissues by RT-PCR. In addition, phylogenetic relationships between amino acid sequence of the pigeon AvBD5, AvBDs from other avian species, and some mammalian beta-defensin-5 were analyzed. The cDNA of pigeon AvBD5 was sub-cloned into pGEX-6p-1 vector to construct recombinant plasmid pGEX-pigeon AvBD5. The recombinant protein was expressed into E. coli and purified. Antimicrobial activity and physical-chemical stability of the recombinant fusion protein were measured in vitro. The complete nucleotide sequence of both cDNAs contained 201 bp nucleotides, encoding a polypeptide of 66 amino acids. Both beta-defensins have six conserved cysteines. Phylogenetic relationships were analyzed. Both pigeon AvBDs shared the highest amino acid homology (87.9% and 78.8%) with duck AvBD5. So it was named as pigeon AvBD5alpha (bone marrow) and AvBD5beta (liver). Both recombinant plasmids were transformed into E. coli BL21 and the bacteria were induced with Isopropyl beta-D-1-Thiogalactopyranoside (IPTG). After purification, antibacterial activity of the purified was investigated. In addition, effect of ionic strength on the antibacterial activity, and hemolytic recombinant protein activity of the purified recombinant protein were investigated. A 32 kDa protein was highly expressed. Both purified recombinant pigeon AvBD5alpha and AvBD5beta exhibited extensive antimicrobial activities against 12 bacteria, including Gram-positive and Gram-negative. In high salt ions concentrations, antibacterial activity of both recombinant proteins was decreased. In addition, the hemolysis activity of recombinant protein was extremely low.