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E-Defense shake table experiments on a 7.5 m tall, 1.8 m by 1.8 m square bridge column using polypropylene fiber-reinforced cement composites (PFRC) at the plastic hinge region and part of the footing is presented. The column was excited using 80% of the original intensity of the near-field ground motion recorded at the JR Takatori Station during the 1995 Kobe, Japan earthquake. Use of PFRC mitigated cover and core concrete damage, local buckling of longitudinal bars, and deformation of ties even after six times of repeated excitation. The damage sustained was much less than the damage of regular reinforced concrete columns.

It is commonly accepted that the Branchiostoma lancelets in South and North China belong to Branchiostoma belcheri (Gray, 1847) and Branchiostoma belcheri tsingtauense (Tchang and Koo, 1934),respectively. Three partial mitochondrial DNA (mtDNA) fragments of cytochrome oxidase c subunit I (COI), cytochrome b (Cytb), and 16S ribosomal RNA (16S rRNA) genes were sequenced to analyzephylogenetic relationships of the Branchiostoma lancelets from South (Xiamen) and North (Qingdao and Rizhao) China, and phylogenetic trees constructed also included the existing data from Japanese waters.The genetic distances of the lancelets between South and North China averaged 0.19, 0.21, and 0.17 based on partial sequences analysis of COI, Cytb, and 16S rRNA genes, respectively, which were muchhigher than those observed in other intraspecific variations. However, the value between North China and Japanese waters was only 0.01 based on partial sequences analysis of three mtDNA genes, whichindicated low intraspecific genetic divergence existed in the two areas. The results also clearly indicated two monophyletic clades (clade A (North China and Japanese waters), clade B (South China)) existed inthe specimens, corresponding to the South and North China, respectively. Above all, our results indicate that the Branchiostoma lancelets in South and North China should belong to different species, and the original subspecies B. belcheri tsingtauense together with the lancelets in most Japanese waters is an independent species. According to the rule of priority and present studies, the B. lancelets in North China and most Japanese waters should be revised to Branchiostoma japonicus. The divergence time between B. belcheri and B. japonicus was estimated at about 39.90 - 43.24 million years ago.

The first hypervariable region (HVR-1) of the mitochondrial DNA control region was utilized for determination of genetic variation and population structure in willowy flounder (Tanakius kitaharai) collected from Aomori, Ibaraki and Niigata. A total of 35 haplotypes were detected among 66 individuals with a total of 30 variable sites out of 387 bp sequenced. Average sequence differences between populations (1.0 - 1.1%) were comparable to those within populations (0.9 - 1.2%), suggesting no genetic heterogeneity among samples. The pattern of distribution of genetic variability with high level of haplotype diversity (h = 0.94) and moderate nucleotide diversity ( = 1.0%) was also detected in theHVR-1 region of the mitochondrial DNA control region. AMOVA tests and the conventional population st comparisons revealed no significant genetic structure among the populations. Partitioning populations into coherent geographic groups divided willowy flounder samples (ct = -0.007, P > 0.05) into two major groups: a Sea of Japan group composed of Aomori and Niigata populations; a Pacific Ocean group composed of Ibaraki populations. The minimum spanning tree constructed with 35 haplotypes showed four low-divergent clades, corresponding to those defined in the NJ tree. However, these clades did not appear to have geographic structure. Altogether, the results indicate that willowy flounder is panmictic throughout the examined range in Aomori, Ibaraki and Niigata.