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Abstract: A nitrogen dioxide (NO2) gas sensor using dual track surface acoustic wave (SAW) device was developed and fabricated in this paper. The dual track architecture and the MSCs were skillfully applied to the sensor. The external perturbations were eliminated by the dual track architecture, and the bulk acoustic wave (BAW) was suppressed by Multistrip coupler (MSC). The input IDT apodized by Morlet wavelet function can improve the side lobe rejection compared with uniform IDT. Utilizing Tungsten powders, hydrogen peroxide, absolute methanol and polyvinylpyrrolidone as raw materials, the micro-porous network Tungsten trioxide (WO3) film sensitive to NO2 gas was fabricated in measurement acoustic track of dual track SAW device. Experiments results confirm that the NO2 gas sensor using dual track SAW device has good response characteristics to different concentrations NO2 gas from 0.5ppm to 10ppm. Furthermore, the NO2 gas sensor using dual track SAW device has good reproducibility and stability. [Copyright &y& Elsevier]

The emergence of novel avian influenza reassortants in wild birds in recent years is a public health concern. However, the viruses that circulate in migratory birds are not fully understood. In this study, we summarized and categorized global H11 avian influenza viruses and reported that waterfowl and shorebirds are the major reservoirs of the identified H11 viruses. The surveillance data of the 35,749 faecal samples collected from wild bird habitats in eastern China over the past seven years revealed a low prevalence of H11 viruses in birds, with a positive rate of 0.067% (24 isolates). The phylogenetic analysis of the twenty viruses indicated that H11 viruses have undergone complex reassortment with viruses circulating in waterfowl and shorebirds. These tested viruses do not acquire mammalian adaptive mutations in their genomes and preferentially bind to avian-type receptors. Experimental infection studies demonstrated that the two tested H11N9 viruses of wild bird origin replicated and transmitted more efficiently in ducks than in chickens, whereas the pigeon H11N2 virus isolated from a live poultry market was more adapted to replicate in chickens than in ducks. In addition, some H11 isolates replicated efficiently in mice and caused body weight loss but were not lethal. Our study revealed the role of waterfowl and shorebirds in the ecology and evolution of H11 viruses and the potential risk of introducing circulating H11 viruses into ducks or chickens, further emphasizing the importance of avian influenza surveillance at the interface of migratory birds and poultry.

A palladium-catalyzed aromatic dual C-H acylations followed with intramolecular cyclizations have been developed by the assistance of bidentate N -(quinolin-8-yl)benzamide. This tandem process involves the formation of three new chemical bonds, providing access to novel quinoline-substituted hydroxyl isoindolones skeleton under simple reaction conditions. The deuterium-labeled competition reaction has revealed that C-H bond cleavage is the turnover limiting step.