On the Tokara Islands, located south-west of the Kyushu Island and consisted of nine islands, there has been a sharp decrease in the size of population after the World War II. The changing pattern in the decrease differs by islands, and the author intended to get the ecological understanding of the phenomenon. The data used were the resident-registration cards in the office of Jutto-Son, which is an administrative unit covering the Tokara Islands, and the information obtained from field surveys on the islands. The decrease to half from 1955 to 1970 is clearly due to the emigration and the drop of fertility, but the process of emigration differed by islands. We could classify the different process into three tvoes: (1) Simultaneous decrease in the number of inhabitants and of households: Nakanoshima, Suwanosejima and Kodakarajima. (2) Succesive decrease, i. e., the decrease in the number of households after that of population size: Takarajima. (3) Limp-decrease, i. e., only the size of population had shown the decrease and the number of households had stayed almost constant or shown a slight decrease: Kuchinoshima, Tairajima and Akusekijima. This type may shift to the Type 2 in the future. The difference of the changing pattern was discussed in connection with the impact of economic change, the social structure and the size of population.
Six prefectures in the Tokyo metropolitan area, i.e., Tokyo, Kanagawa, Saitama, Chiba, Gunma and Ibaragi, differing in the extent of urbanization and gerontization, were selected and changes in 16 health indicators between 1945 and 196'5 in these prefectures were examined. Those indicators showing clear changes in these years and corresponding with urbanization were gross mortality rate, infant mortality rate, death rate from gastritis and enteritis, and from nephritis and nephrosis. Those ralated to gerontization were PMI, and deaths caused by vascular lesions, and by malignant neoplasms. Considering all three studies together, we can conclude that the infant mortality rate best represents urbanization, and PMI is the best index of gerontization. These two indices also closely correspond with chronological changes in LSL in the post-world War II period.
This paper concerns the tryptophan determination in the fimbrial protein, which were taken off and purified from thefimbriate cells of Shieglla fiexneri Several methods were used for the tryptophan determination, including the absorption spectra in terms of tyrosine and tryptophan content, amino acids analysis of the fimbrial protein hydrolysed with alkaline, and color-forming reaction of tryptophan (p-dimethylaminobenzaldehyde). Although qualitative measurement from the absorption spectra suggested the presence of tryptophan residues in this protein, it was not able to estimate the content of tryptophan residues by other physico-chemical methods.