This volume of the Keio University International Symposia for Life Sciences and Medicine contains the proceedings of the 13th symposium held under the sponsorship of the Keio University Medical Science Fund. The fund was est- lished by the generous donation of the late Dr. Mitsunada Sakaguchi. The Keio University International Symposia for Life Sciences and Medicine constitute one of the core activities sponsored by the fund,of which the objective is to contribute to the international community by developing human resources, promoting scienti?c knowledge, and encouraging mutual exchange. Each year, the Committee of the International Symposia for Life Sciences and Medicine selects the most signi?cant symposium topics from applications received from the Keio medical community. The publication of the proce- ings is intended to publicize and distribute the information arising from the lively discussions of the most exciting and current issues presented during the symposium. On behalf of the Committee, I am most grateful to the late Dr. Sakaguchi, who made the series of symposia possible. We are also grateful to the prominent speakers for their contribution to this volume. In addition, we would like to acknowledge the ef?cient organizational work performed by the members of the program committee and the staff of the fund. Naoki Aikawa, M. D. , D. M. Sc. , F. A. C. S.

We all know that networks are fundamental prerequisites for prosperity and production. Transportation and communication are indispensible to society, they are the elements which bind all economic systems together. Without networks and communica tion all social and economic life will be reduced to isolated phenomena. Therefore, transportation can't be assessed in the same way as other services. A smoothly functioning system of communications is also a prerequistite for social and economic integration between separate geographical regions. The modernization of the infrastructure is therefore an urgent task and a precondition for carrying out the whole of Europe's ambitious political, economic and social agenda. Since the need for communication and transportation does not know any national borders, the functioning of the networks needs to be adopted to this new economic and political geography. Congestions of cities, highways, railroads, airways and tele communications must be tackled, if precious working, commuting and leisure time is not to be wasted and heavy burdens on the environment avoided. European traffic, is for example, expected to double within the next twenty years. In certain transport modes the growth is expected to be even faster - air passenger transport doubled in 10 years and goods transport on roads doubled in 15 years."

This volume of the Keio University International Symposia for Life Sciences and Medicine contains the proceedings of the 13th symposium held under the sponsorship of the Keio University Medical Science Fund. The fund was est- lished by the generous donation of the late Dr. Mitsunada Sakaguchi. The Keio University International Symposia for Life Sciences and Medicine constitute one of the core activities sponsored by the fund,of which the objective is to contribute to the international community by developing human resources, promoting scienti?c knowledge, and encouraging mutual exchange. Each year, the Committee of the International Symposia for Life Sciences and Medicine selects the most signi?cant symposium topics from applications received from the Keio medical community. The publication of the proce- ings is intended to publicize and distribute the information arising from the lively discussions of the most exciting and current issues presented during the symposium. On behalf of the Committee, I am most grateful to the late Dr. Sakaguchi, who made the series of symposia possible. We are also grateful to the prominent speakers for their contribution to this volume. In addition, we would like to acknowledge the ef?cient organizational work performed by the members of the program committee and the staff of the fund. Naoki Aikawa, M. D. , D. M. Sc. , F. A. C. S.