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3,4-Di-(2 -hydroxyethoxy)-4 -nitrostilbene (2) was prepared by the reaction of 2-iodoethanol with 3,4-dihydroxy-4 -nitrostilbene. Diol 2 was condensed with 2,4-toluenediisocyanate, 3,3 -dimethoxy-4,4 -biphenylenediisocyanate and 1,6-hexamethylenediisocyanate to yield novel Y-type polyurethanes 3-5 containing dioxynitrostilbene as a non-linear optical (NLO)-chromophore. Polymers 3-5 were soluble in common organic solvents, such as acetone and DMF. These polymers showed thermal stability up to 280 • C in TGA thermograms with T g values in the range of 100-143 • C in DSC thermograms. The approximate lengths of aligned NLO-chromophores of the polymers estimated from AFM images were around 2 nm. The SHG coefficients (d 33 ) of poled polymer films were around 4.5 × 10 −8 esu. Poled polymer films had improved temporal and long-term thermal stability owing to the hydrogen bonding of urethane linkage and the main-chain character of the polymer structure, which are acceptable for NLO device applications.

Abstract. Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia, a highly contagious pulmonary disease in pigs with major economic losses for pig producers worldwide. Whereas A. pleuropneumoniae isolates are divided into 15 serotypes, the isolates secrete 4 types of exotoxins (ApxI, ApxII, ApxIII, and ApxIV), which are known as major virulence factors. In the current study, the ApxIA, ApxIIA, and ApxIIIA genes were amplified and their recombinant proteins expressed in Escherichia coli M15 cells. The antigenicity of each recombinant protein was demonstrated by Western blot and enzyme-linked immunosorbent assay (ELISA) using sera from pigs vaccinated with a subunit vaccine. When ELISAs using the recombinant antigens were optimized and then applied to sera from 320 randomized pigs in Korea, an observed increase in seroprevalence was found among sows in comparison with weaned piglets and growing pigs, indicating an age-dependent seroprevalence. The results obtained in the study suggest that the developed ELISAs may be useful for A. pleuropneumoniae vaccination strategy as a screening tool for pig herds as well as for detection of specific antibodies to Apx exotoxins.