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Newcastle disease virus (NDV) causes a highly contagious viral disease in poultry and wild birds, and it can cause significant economic loss worldwide. Eight viral strains were isolated by inoculating embryonated chicken eggs from the Poyang Lake region of China with swab samples. All eight of the NDV isolates were identified as class I genotype 3 strains, but they diverged notablely from class II viruses. Further analysis revealed that all eight NDV isolates were lentogenic strains containing the 112ERQER↓L117 motif at the F protein cleavage site. The strains were highly identical and were more species specific (chicken and waterfowl) than site specific (Nanchang and Duchang regions). The close phylogenetic proximity of these isolates indicates that viral transmission may happen between poultry and wild birds. Our study demonstrates that lentogenic class I NDVs exist in clinically healthy wild waterfowl and poultry within the Poyang Lake region. Active surveillance of these viruses to determine their evolution and origin is one of the most realistic strategies for preventing and controlling NDV outbreaks. [ABSTRACT FROM AUTHOR]

In this paper, a dynamic wear modeI to predict wear volume in a mechanism, involving aleatoiy and epistemic uncertainty, is established. In this case, harmonic drives are applied to alleviate the impact of clearance for wear of the mechanism. The contact model of a mechanism with clearance that is subjected to harmonic drive is established, with the nonlinear spring-damp model and flexibility of harmonic gear considered. Especially, a slider-crank mechanism with clearance is simulated. The result shows that the cushioning effect of collisions for clearance with application of harmonic drive is superior to that through the flexibility of mechanical parts. Following confidence region method (CRM) for quantification of aleatory and epistemic uncertainty is proposed to analyze the effect of parameter uncertainty for wear volume during the entire time domain, and double-loop Monte Carlo sampling (MCS) approach is improved to propagate uncertainties during the entire time domain. Finally, based on Kriging model, the CRM is used to analyze the effect of parameter uncertainty for wear volume. The result shows that, when both alea-tory and epistemic uncertainties are considered, the wear volume boundary is wider and better than that when only aleatory uncertainty is considered. These analyses help to improve the reliability design of system and set a theoretical foundation for the mechanic design and precision analysis of the mechanical system. [ABSTRACT FROM AUTHOR]