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In view of the development demand of biomaterials for bone substitute, the development status of polymer materials, metal materials, bioceramic materials and composite materials for bone replacement were summarized. The advantages of bioceramic materials in mechanical properties, chemical properties and biological properties as bone substitute materials were emphatically introduced. The bioceramic materials play an important role in the field of bone substitute materials due to their similar density and composition to human bone, significant bio-compatibility, high mechanical strength, and stable chemical properties. In this study, the research status of bioceramic materials represented by phosphate, silicate, oxides and non-oxides was systematically discussed, and the advantages and limitations of bioceramic materials and their composites as bone substitute biomaterials study were discussed. Finally, the future development direction of bioceramic materials was prospected. [ABSTRACT FROM AUTHOR]

The influences of the oxidation temperature, the oxidation time, the impurities, the particle size and the additive type on the oxidation behavior of SiAlON-based materials in China and abroad were summarized. It was pointed out that each factor had obvious effects on the phase composition, the microstructure, and the oxidation rate of the oxidation products, expecting to provide references for improving the service life of SiAlON-based materials. The future research direction was also indicated. [ABSTRACT FROM AUTHOR]

The direct economical losses and the tolls of earthquakes are main impacts of earthquake insurance. This paper collected the loss data of earthquake during the years 1950-2015 in China and modeled the direct economical losses and the tolls of earthquake using Copula-mixed distribution model. First, the truncated Gumble distribution and generalized Pareto distribution are mixed to fit the direct economical losses, and the truncated negative binominal distribution and generalized Pareto distribution are mixed to fit the tolls of earthquake. Second, copulas are used to model the dependence between the direct economical losses and the tolls of earthquake. Finally, Monte Carlo simulation method is used to calculate VaR and ES. The models proposed in the paper may be applied to establish earthquake insurance system in China. [ABSTRACT FROM AUTHOR]

Objective: To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness., Methods: Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13 +6 gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test., Results: The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13 +4 weeks (11 +5 ~ 13 +6 weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS., Conclusion: NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.