Congenital malformations or birth defects are a major public concern. However, lack of proper information may panic a pregnant woman who had taken medicines without noticing the pregnancy, and thus may result in an unnecessary abortion. We have undertaken a new research/development project to create an information-community for teratogenic agents, consisting of pregnant women, pharmacists, physicians and research scientists working on medicinal products. We have designed a trial database system for teratogenic agents. The database performs not only retrieval of teratogenic information and chemical structures of drugs/medicinal products, but also registration of clinical case reports and teratogenic information on various chemicals. Our system will be useful for clinical risk-assessment of teratogenic exposures in pregnant women and for the development of new drugs based on chemical information and computer science.

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The chemical industry can contribute to global sustainability by integration of evaluation of environmental impact with product and process design activities. We constructed an activity model to incorporate life cycle assessment (LCA) into the early phase of chemical process design. We showed that reaction, process and life cycle strongly relate to each other, and proposed a methodology for the selection of chemical process from the view point of environmental impact by performing a case study, in which a chemical recycling process for PET resin was selected. An integrated information infrastructure, which is constructed by hierarchical models of reaction, unit operation, process and life cycle, is needed for the design of chemical products and processes based on LCA.

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The accuracy of the chemical reaction data of a reaction database is verified to determine the validity for practical use in chemical research. Reaction databases have been traditionally used in data-search, but recently, there have been some approaches deriving knowledge for synthetic design and reaction prediction systems. The design and prediction based on the approaches are providing valid scientific technologies that could provide a new chemical research style in which design and prediction are done before experiments. The technologies must give an answer to the serious issues concerning the environments of Earth, and are expected to reduce the number of experiments, predict a synthetic route producing no useless side-reaction products, and design environmentally friendly catalysts and reagents for replacing to hazardous and toxic ones. In the reaction prediction and synthetic design systems based on a reaction database, the quality and contents of the reaction database are of critical importance. Low quality and lack of contents may lead to wrong outputs from the systems. High accuracy of reaction data is particularly essential for both database search and knowledge derivation, and a reaction database is accordingly verified in order to determine the correctness of the data. The verification is done using 329 sampling reaction data from 600, 000 data in a commercially available database, and 151 error data are found. The types of error concern planar and/or stereochemical structures, the number of reaction steps, reaction schemes, reaction sites, reaction conditions, product ratios, and article information. This paper describes the results from the verification and discussion of the problems for practical use in the current available reaction databases.

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We present studies of periodic patterns in nucleotide sequence and characterization for nucleotide sequences that confer periodicities to Caenorhabditis elegans, Arabidopsis thaliana, Drosophila melanogaster, Anopheles gambiae, and Homo sapiens by the power spectrum method and frequency of nucleotide sequences. To assign periodic regions in genome, we used periodic nucleotide distributions by a parameter F_k. For worm genome, a 68-bp periodicity in chromosome I, a 59-bp periodicity in chromosome II, and a 94-bp periodicity in chromosome III were found. In A. thaliana, we obtained three periodicities (248 bp-, 167 bp-, and 126 bp) in chromosome 3, three peaks (174 bp-, 88 bp-, and 59 bp-period) in chromosome 4, and four periodicities (356 bp, 174 bp, 88 bp, and 59 bp) in chromosome 5. These are related to ORF that consists of Gly-rich amino acid sequences. 167- or 84-bp periodicity was detected along the entire length of these chromosomes for human chromosomes 21 and 22. The 167-bp is identical to the length of DNA that forms two complete helical turns in nucleosome. For insect genomes (D. melanogaster and A. gambiae), we found that G or C spectral curves have flat regions at middle frequency, which may be associated with randomness of base sequence composition. This property has not been observed in Saccharomyces cerevisiae, C. elegans, A. thaliana, and H. sapiens yet.

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We developed a special purpose parallel computer: Embedded High Performance Computer (EHPC) for the first principle DVXα calculations, which realizes super high performance and cost-down for large scale first principle material simulation.
An EHPC unit consists of one host-board (Pentium III 400MHz) and 7 acceleration-boards. Four general purpose processors (SH4 200MHz) are equipped on a board. The EHPC unit has 28 processors connected to each other by Compact PCI-bus.
The step of matrix elements generation where more than 90% computation time is required was efficiently parallelized on the system. In the case of Si₇₈B₆H₅₃ cluster, the special purpose computer with four EHPC units is almost 100 times faster than a lone Pentium III processor. Super-linear speed up has been observed at the matrix elements generation step.

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