Magnetic resonance imaging of the internal structure of the mouse fetus

Magnetic resonance imaging (MRI) has potential as an imaging technique in fetal anatomy. In this article are presented images obtained from mouse fetuses at 16 days of pregnancy by means of the ultraconductive MRI system (JEOL AIM270). When fetuses removed from the uterus were fixed with 10% neutral formalin, various organs including heart, liver, lungs and bones were clearly seen, and a clear outline was obtained of the fetal skin and subcutaneous tissue by varying the setting. The same specimens were able to be used for histological evaluation. This MRI system will allow wider application in fetal anatomy and provide additional information about the developing mouse fetus.

Growth trends of metropolitan areas in Japan: application of the concept of P-M curve

"The aim of this paper is to illuminate basic characteristics of metropolitan areas in Japan. [The authors] first delineate the boundaries of ninety-eight Japanese metropolitan areas based on the concept of cut-off point on the P-M curve the idea of which was originally developed by Ogawa in 1957. Secondly, [they] carry out empirical analyses on spatial structure and growth patterns of those metropolitan areas by use of 1960 and 1975 data." The results indicate that the population share of central cities declined from 1960 to 1975.