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Based on the aerostatic and self-excited aerodynamic force models, a computational approach of three-dimensional (3D) refined flutter analysis for long-span bridges under skew winds is established, in which the structural nonlinearity, aerostatic effect and full-mode coupling effect, etc., are fully considered, and the computational procedure ([Formula: see text] flutter-sw) is developed accordingly. By taking the Runyang Suspension Bridge over the Yangtze river as an example, under the wind attack with initial angles of 0∘ and [Formula: see text] and yaw angles between 0∘ and 25∘, the flutter stability of the bridge in completion under skew winds is analyzed, and the influences of skew wind and aerostatic effect on the flutter stability of suspension bridges are assessed. The results show that the aerostatic effect has a significant influence on the flutter stability of long-span suspension bridge, and it may worsen its flutter stability, with an average decrease of 6.0%. However, it does not change the evolution of flutter stability of suspension bridge with increasing wind yaw angle. The critical flutter wind speed fluctuates with the increase of wind yaw angle, and it reaches the lowest value mostly under the skew wind, with an average reduction of 8.0%. The combined influence of the aerostatic effect and skew wind further reduces the flutter critical wind speed by 11.5% on average, and therefore, the aerostatic effect, skew wind effect and their adverse influences need to be comprehensively considered in the flutter analysis of long-span suspension bridges.

The rice line carrying the nonhost gene Rxo1, which was cloned from maize, exhibits a rapid hypersensitive response (HR) to Xanthomonas oryzae pv. oryzicola (Xoc). In this study, a microarray experiment was carried out to analyze the genome-wide gene expression responses to Xoc at the early stage in the rice transgenic line and its wild type. 175 and 379 differentially regulated genes (DRGs) were detected in 9804-Rxo1 and 9804 at 36 h post-inoculation (hpi), respectively. The patterns of DRGs induced by Xoc in the transgenic rice line and its wild type were distinctly different: 92.00% of the DRGs were up-regulated in inoculated 9804-Rxo1 and 48.22% of the DRGs were sorted as defense-related genes. In contrast, 40.69% of the DRGs were up-regulated in inoculated 9804 and 40.00% were sorted as injury-induced genes. Some genes specifically up-regulated in infected 9804-Rxo1 were defenserelated, including the genes encoding pathogenesis-related protein, terpene synthase family, transcription factors (TFs) AP2 domain containing protein, myb-like deoxyribonucleic acid (DNA)- binding domain containing protein, and C 2 H 2 -type zinc-finger transcription factors. Six peroxidase (POD) genes were significantly up-regulated and POD activity consistently rose in the inoculated 9804- Rxo1, whereas seven POD genes were down-regulated in its wild type, indicating that POD may also play a role in the complex process of resistant response to Xoc in the transgenic line. Instead of focusing only on the R-gene-mediated defense, this study also discusses the susceptible response in the wild types to virulent pathogen infection in transcription level. Key words: Rice bacterial leaf streak, nonhost resistance, expression profile, Rxo1.