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In 2013, the second outbreak of peste des petits ruminants occurred in China, leading to a spillover in more than 20 provinces and municipalities over the next few months. Thereafter, the epidemic situation was stable owing to strict prevention and control measures. In February 2024, several bharals and argali with suspected symptoms of PPR were discovered in Rutog country, Tibet Autonomous Region. Samples collected from these animals were delivered to our laboratory for diagnosis; the results of fluorescence quantitative reverse-transcription (RT) PCR indicated that all samples were positive for PPR viral RNA. The N and F gene fragments were amplified successfully via RT-PCR, and these results confirmed that these animals were infected with PPRV. A PPRV strain (subsequently named ChinaTibet2024) was sequenced, and its genome length was 15,954 nucleotides. A phylogenetic tree analysis using N and F genes and viral genomes showed that the ChinaTibet2024 genome was classified into lineage IV of the PRRV genotypes. The genome of the ChinaTibet2024 strain was found to be closely related to PPRVs isolated in China between 2013 and 2014. A base insertion and a base deletion were detected in the M gene 5′ untranslated region. Results indicated that the prevalent PPRV strains in China did not show significant changes and that special attention should be paid to the surveillance of wild animals as an important part of PPR prevention and control.

The numerical shock instability problem significantly limits the application of the finite volume method in hypersonic flow simulations, especially for high-order schemes, which will encounter more severe shock instability problems. In the previous work, the MSAT (matrix stability analysis tool) was introduced to quantitatively analyze the numerical shock instability problem. However, the utilization of the three-point reconstruction stencil in the original version of MSAT presents challenges in conducting investigations into high-order schemes. The current work provides an extension of MSAT by extending the reconstruction stencil to five points, a challenging but necessary endeavor for high-order schemes. This extension enables MSAT to provide analyses for schemes with high-order reconstruction methods. Furthermore, the updated MSAT can be utilized to investigate the impact of characteristic variable reconstruction on the shock instability problem. Results demonstrate the reliability of the updated MSAT and reveal novel characteristics in the shock instability of high-order schemes. Consequently, the updated MSAT will contribute to the investigation of shock instabilities for high-order schemes, ultimately aiding in mitigating this challenging problem.

The second phases at grain boundaries including block-shaped long-period stacking ordered (LPSO) phases and bright W phases are the chief culprits damage the deformability of as cast Mg-Gd-Y-Zn-Zr magnesium alloy. The industry homogenization (520 °C/12 h) is indispensable for microstructure homogeneity, but has the disadvantages including long period, low efficiency and high oxidation burning rate. Here it was found that the microstructure homogeneity can be rapidly performed under electropulsing at a relative low temperature of 422 °C, and the holding time is only 10 min. The block-shaped LPSO phases and bright W phases at the grain boundaries were selectively dissolved and decomposed. The volume fraction of the second phases was reduced from 17 % to 12 %, indicating that the electropulsing is a more efficient method. Meanwhile, the elongation was enhanced to 6.2 %, which is higher than that of the traditional industry homogenized sample. The numerical calculation results present that the high current density regions at the tips of lamellar LPSO phases (near the grain boundaries) are the key factors to accelerate the solute elements exchange, so as to complete the fast microstructure homogeneity enhancement.

Near-infrared laser radiation based on Nd3+-doped yttrium ortho-aluminate (Nd:YAlO3, Nd:YAP) has garnered significant interest regarding solid-state lasers. Nevertheless, the crystal microstructures and electronic characteristics of Nd:YAP are still unclear, and the unique physical properties underlying its enormous applications require clarification. In this study, we conducted first-principles calculations at the atomic level to explore the electronic properties and mechanical characteristics of both pure YAP and Nd3+-doped YAP. The results suggest that the substitution of the Y3+ ion site with the Nd3+ impurity ion induces slight structural distortion in the YAP crystal lattice. An impurity band emerges between the original conduction band and the valence band, attributed to the 4f orbital of the Nd3+ ion, exerting a substantial influence on the narrowing of the band gap. Through an analysis of the mechanical characteristics of both pure YAP and Nd:YAP, we conclude that the incorporation of Nd3+ atoms leads to a reduction in the mechanical properties of YAP to a certain extent. Our study can serve as a foundational data source for investigations into material performance, especially for the application of Nd:YAP in solid-state laser systems.