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ORCHID (Open linguistic Resources CHanelled toward InterDisciplinary research) is aninitiative project aimed at building linguistic resources to support research in, but not limited to, natural language processing. Based on the concept of an open architecture design, the resources must be fully compatible with similar resources, and software tools must also be made available. This paper presents one result of the project, the construction of a Thai part-of-speech (POS) tagged corpus, which is a preliminary stage in the construction of a Thai speech corpus. The POS-tagged corpus is the result of collaborative research between the Communications Research Laboratory (CRL) in Japan and the National Electronics and Computer Technology Center (NECTEC) in Thailand, with technical support from the Electrotechnical Laboratory (ETL) in Japan. In this paper, we propose a new tagset, based on the results of a prior multilingual machine translation project. The corpus is annotated on three levels : the paragraph, sentence, and word levels. Text information is maintained in the form of the text information lines and the number lines, which are both utilized in data retrieval. Both word segmentation and POS tagging were carried out by way of a probabilistic trigram model. Rules for syllable demarkation were additionally used to reduce the number of candidates in computing tagging probabilities.Some typical problems in POS assignment are also formalized to resolve ambiguity.

The Horoman peridotite complex, Hidaka belt, Hokkaido, northern Japan, is composed of three peridotite suites which have distinct petrographic characteristics. The first is the Main Harzburgite-Lherzolite (MHL) suite, which occupies the most part of the Horoman peridotite complex. The MHL suite consists of harzburgite, spinel lherzolite and plagioclase lherzolite, which form a layered complex with gradational layer boundaries. Two-pyroxene spinel symplectite, which is interpreted as a chemically modified garnet pseudomorph, occurs in spinel and plagioclase lherzolites. The MHL suite is of typical residual origin after various degrees of magma extraction, which resulted in wide chemical variations. The second, the Banded Dunite -Harzburgite (BDH) suite, consists of conspicuously layered dunite, harzburgite and olivine orthopyroxenite with sharp layer boundaries. The BDH peridotites are probably exotic blocks within the MHL suite. Mineralogical characteristics of the BDH suite suggests that it is a cumulate from a high-Mg magma (e.g., high-magnesian andesite). The third, the Spinel-rich Dunite-Wehrlite (SDW) suite, consists of dunites containing abundant large oblate chromian spinel grains. The dunite becomes locally wehrlitic and contains clinopyroxene up to 8%. The SDW occurs in the MHL harzburgite zones as layers with maximum thickness of 15m. The layer boundaries with the harzburgite of the MHL suite are generally sharp. The petrographical and mineralogical characteristics show that the SDW is a cumulate from a magma segregated from the surrounding MHL suite. The melt segregation may be caused by formation of cracks in upwell ing mantle materials just before the mantle materials spreading away from the upwelling center as a corner flow. A series of layered residual peridotite (MHL suite) zones, of which degree of melt extraction increases inwards, formed around the SDW dikes. I. IntroductionSeveral mechanisms of the melt segrega tion in the mantle have been proposed. There are, however many controversies on this matter (e.g., Sleep, 1974Sleep, , 1988Nicolas, 1986Nicolas, , 1989 Nagasaki, 1966;Niida, 1974Niida, , 1975Niida, , 1984Obata and Nagahara, 1987). After the pioneering works of Nagasaki (1966) and Niida (1984), Obata and Nagahara (1987) presented a interesting model for the origin of the gradual layering of the lower part of the complex; they interpreted that the layering represents upward moving melt wave which was frozen as an alternation of highly depleted residual and melt-enriched fertile zones. Their idea of the origin of layering looks very attractive because it provides a plausible expla nation for melt segregation processes.In con trast, Takahashi (1988MS, 1991 performed detailed petrological works and found that the Horoman complex is composed of quite various kinds of ultramafic rocks, which had been produced by time-integrated igneous processes in the upper mantle. Horoman complex may have undergone tectono-magmatic evolution in the upper mantle, and its petrologic diversity can not be exp...

Marine-derived collagen is expected to be a much safer alternative to calf collagen, which in medical applications carries the risk of bovine spongiform encephalopathy. In this study, acid-soluble collagen was extracted from salmon skin and crosslinked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide during fibril formation to produce a crosslinked salmon collagen (SC) gel. The growth rates and the differentiated functions of human periodontal ligament fibroblasts (HPdLFs) cultured on the SC gel were investigated. Growth was faster on the SC gel than on porcine collagen (PC) gel. In addition, the HPdLFs cultured on the SC gel exhibited higher alkaline phosphatase (ALP) activity than those cultured on the PC gel. Quantitative RT-PCR revealed higher mRNA expression of type I collagen, ALP, and osteocalcin in the HPdLFs cultured on the SC gel. HPdLFs had a flat shape on the SC gel and a spindle shape on the PC gel, as revealed by observation with scanning electron microscopy and immunostaining with cytoskeletal protein and vinculin. The results showed that HPdLFs could grow and show highly differentiated activity on the SC gel as well as on the PC gel.