Evaluation of activated area in the electrostatic accelerator facilities

In order to clear the activated area in electrostatic accelerator facilities,four accelerator facilities were selected and typical neutron emission experiments were performed.Neutron flux during operation and induced activity caused by charged particles on the accelerator and its surrounding area after irradiation were measured.Also the monitored neutron flux and calculated value by Monte Carlo calculation using PHITS code were compared.It was confirmed that the results between calculated data and measured data showed the good agreement with each other.Finally,it was concluded that we have to take care the activation of beam line and target.But,it is not necessary to treat accelerator tank,surrounding materials,and building concrete as radioactive materials in case of decommissioning.

空回肠闭锁时胎盘血管的损伤

背景/目的:子宫内血管破裂导致胎儿空回肠闭锁(JIA)发生的机制尚未完全阐明。现认为单绒毛膜双胎中一胎的死亡与通过胎盘进行物质交换幸存者JIA的产生有关。该研究的目的是评价是否有胎盘血管参与JIA的发生。方法:对Tsukuba大学附属医院1978-2003年收治的45例JIA新生儿(23例男婴,22例女婴)进行回顾性分析。