The article is available at
http://link.aps.org/doi/10.1103/PhysRevD.81.046006.
I would like to thank the referee for critical comments; without the comments I would never be able to realize my mistakes in the original version of this paper. So I am grateful to the referee very much.
Accordingly I have revised my doctoral dissertation since it contains most of the materials in the paper. A revised dissertation in an abridged style is now available at
arXiv:1002.4937 [hep-th].
Updated information on Yasuhiro Abe | a personal web page
