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An understanding of physiological damage and population development caused by uncomfortable temperature plays an important role in pest control. In order to clarify the adaptability of different temperatures and physiological response mechanism of B. dorsalis , we focused on the adaptation ability of this pest to environmental stress from physiological and ecological viewpoints. In this study, we explored the relationship between population parameters and glucose, glycogen, trehalose, and trehalose-6-phosphate synthase responses to high and low temperatures. Compared with the control group, temperature stress delayed the development duration of all stages, and the survival rates and longevity decreased gradually as temperature decreased to 0 °C and increased to 36 °C. Furthermore, with low temperature decrease from 10 °C to 0 °C, the average fecundity per female increased at 10 °C but decreased later. Reproduction of the species was negatively affected during high-temperature stresses, reaching the lowest value at 36 °C. In addition to significantly affecting biological characteristics, temperature stress influenced physiological changes of B. dorsalis in cold and heat tolerance. When temperature deviated significantly from the norm, the levels of substances associated with temperature resistance were altered: glucose, trehalose, and TPS levels increased, but glycogen levels decreased. These results suggest that temperature stresses exert a detrimental effect on the populations' survival, but the metabolism of trehalose and glycogen may enhance the pest's temperature resistance.

In this study, using ethylene carbonate and ethanolamine, we synthesized a novel diol chain-extender, bis-hydroxylethyl carbomate (EC-AE), which contains carbomate structure. The polyurethanes, PUA25 and PUB25, with different extenders, EC-AE and BDO, were synthesized by one-step polymerization, respectively. Their structures were characterized by using FT-IR and DSC. The results indicated that the microphase separation degree of PUA25 was less than that of PUB25, in other words, the amount of hydrogen bonding between hard segments and soft segments in PUA25 was superior to that in PUB25. And the formation of physically crosslinked hydrogels prepared by PUA25 and PUB25 were studied in detail. It was found that only PUA25 can form hydrogel in situ from solution state by cooling. And this kind of hydrogels showed the transition cycle of "gel-sol-gel" under "cooling-heating-cooling" thermal cycles, respectively. The results suggested that the physically crosslinked polyurethane hydrogels were easily possessed in high degree of phase mixing.

From September 2002 to December 2004, a total of 281 strains of Haemophilus parasuis were isolated from 17 provinces of China. All these isolates were serotyped by both the gel diffusion (GD) and the indirect haemagglutination (IHA) tests. By combining the GD and IHA results, serovar 4 (24.2%) and serovar 5 (19.2%) were the most prevalent serovars, followed by serovars 13 (12.5%), 14 (7.1%) and 12 (6.8%), while 12.1% of the isolates could not be assigned to a serovar (nontypable). A comparison of the number of isolates obtained from the respiratory tract of swine without polyserositis with those obtained from swine with polyserositis revealed an increased frequency of serovar 4 and a significantly decreased frequency of serovar 13 among isolates from the respiratory tract of swine without polyserositis, whereas the frequency of isolation of serovars 5, 12, 14 and nontypable from swine with or without polyserositis were similar. Co-infection of H. parasuis and other bacterial agents was studied in 183 cases examined from June 2003 to December 2004. Streptococcus suis (30.6%; 56), Escherichia coli (21.9%; 40), Bordetella bronchiseptica (21.3%; 39) and Pasteurella multocida (14.2%; 26) were the bacterial agents frequently co-isolated with H. parasuis in China.