An entomopathogenic bacterium, Photorhabdus temperata ssp. temperata (Ptt), suppresses insect immune responses and facilitates its symbiotic nematode development in target insects. The immunosuppressive activity of Ptt enhances pathogenicity of various microbial pesticides including Bacillus thuringiensis (Bt). This study was performed to select a cheap and efficient bacterial culture medium for large scale culturing of the bacteria. Relatively cheap industrial bacterial culture media (MY and M2) were compared to two research media, Luria-Bertani (LB) and tryptic soy broth (TSB). In all tested media, a constant initial population of Ptt multiplied and reached a stationary phase at 48 h. However, more bacterial colony densities were detected in LB and TSB at the stationary phase compared to two industrial media. All bacterial culture broth gave significant synergism to Bt pathogenicity against third instars of the diamondback moth, Plutella xylostella. Production of bacterial metabolites extracted by either hexane or ethyl acetate did not show any significant difference in total mass among four culture media. Reverse phase HPLC separated the four bacterial metabolites, which were not much different in quantities among four bacterial culture broths. This study suggests that two industrial bacterial culture media can be used to economically culture Ptt in a large scale.

The purpose of this study is to trace Yeats’s efforts toward an ultimate reconciliation of the contrary forces of human experience as they are reflected in his later poetry written Beyond Byzantium, and to explore the relationship between existential awareness and artistic vitality. Though Yeats reached Byzantium in 1927, from The Wanderings of Oisin to “Byzantium” he yearned for stasis and release, and thus sought the solace to be found in never-never lands ranging from the woods of Arcady and Tir-nan-Oge to the golden boughs of Byzantium. Yet a disquieted romantic and an unaccommodated man, he returned to the living world of unfinished men and the dross of their mortal pain. The world of the “dying generations,” for all its corruption and impermanence, is the place where Yeats, after much sailing, finally dropped anchor. Yeats ran his course between the extremities implicit in “Perfection of the life, or of the work,” and by the end of his career he took his stand with the claims of his art and the passions that make it possible. “Tragic Gaiety,” the hero’s rising above evil fortune and circumstance, is at once the matrix and the pinnacle of his final, transforming vision, and Yeats’s most significant legacy to our “tired” and “hysterical” age. Thus Yeats’s great achievement lies in his exposition of the artist’s will to transcend phenomenal limitations, and in the symbolic identification of creator and created. “Bitter and Gay,” the dominant notes of most of the poetry of Yeats’s last years, lay the tragic scene beyond Byzantium, and it was there that he finally reached a reconciliation with “Time.” Not transcendence, however, but the simple triumph of trying to be a total man was Yeats’s final accomplishment. After all the anguish and the judgements, at the close of his life he repented nothing, and could cry “Rejoice” because it is only through the despair born of tragedy that we can achieve true gaiety and unity in empathy with humanity. That was the joyful voice of a man who knew how to create out of destruction. This wholeness of vision which Yeats finally attained is the prime concern of this study.