On Acoustic Dispersion In MF₆-type Molecules

Available data on relaxation times in MF₆-type molecule have been incompatible with analytical approaches. Then, we performed experiments on the acoustic dispersion of SF₆, WF₆ and UF₆ gases by using a double crystal ultrasonic interferometer. It was revealed that the available data on WF₆ are not acceptable, and the relaxation time of UF₆ is less than 0.027 μsec・atm at a temperature below 68°C

Studies on the Reasonable Utilization of Water for the Agricultural Area around the Seto-Inland-Sea : (1)Precipitation Character on the Area around the Seto-Inland-Sea

瀬戸内地帯の農業用水の合理的な利用方法を検討するため,先づ瀬戸内海沿岸の兵庫,岡山,広島,山口,香川,愛媛の6県の119の観測地点から1947～1966年の20年間にわたる降水壁記録を収集し,更に岡山,香川両県の17地点からは50年ないし75年間の記録を収集して,瀬戸内地帯の降水特性を把握するための検討を行なった. その結果判明した降水特性をまとめると次のとおりである. (1)岡山―牛窓―高砂―明石―高松―観音寺―因島―笠岡―岡山を結ぶだ円内が瀬戸内気侯帯の中心と考えられ,年降水量はおよそ1,100～1,200mmである. (2)長期にわたる傾向変動が年降水量,月降水量ともに認められる. (3)周期性は認められない. (4)年降水量の変動は,沿岸部が大きく,円陸部に入るに従って安定している. (5)月降水量の年による変動は3月,4月が最も安定しており,8月が最も不安定である. (6)月降水盤の年間の変動係数は50%前後であってかなり大きく,従って利水については不利の状態にある. なおこの研究の一部は文部省科学研究費の援助を受けたものである

Prediction of fetal acidemia in placental abruption

BACKGROUND: To determine the major predictive factors for fetal acidemia in placental abruption. METHODS: A retrospective review of pregnancies with placental abruption was performed using a logistic regression model. Fetal acidemia was defined as a pH of less than 7.0 in umbilical artery. The severe abruption score, which was derived from a linear discriminant function, was calculated to determine the probability of fetal acidemia. RESULTS: Fetal acidemia was seen in 43 survivors (43/222, 19%). A logistic regression model showed bradycardia (OR (odds ratio) 50.34, 95% CI 11.07 – 228.93), and late decelerations (OR 15.13, 3.05 – 74.97), but not abnormal ultrasonographic findings were to be associated with the occurrence of fetal acidemia. The severe abruption score was calculated for the occurrence of fetal acidemia, using 6 items including vaginal bleeding, gestational age, abdominal pain, abnormal ultrasonographic finding, late decelerations, and bradycardia. CONCLUSIONS: An abnormal FHR pattern, especially bradycardia is the most significant risk factor in placental abruption predicting fetal acidemia, regardless of the presence of abnormal ultrasonographic findings or gestational age