Objective:To provide reference for establishing the testing method for quality control of neutron beam in boron neutron capture therapy (BNCT) equipment in China by testing the radiation characteristic parameters and dosimetry characteristic parameters of epithermal neutron beam in hospital neutron irradiator (IHNI).Methods:By comparing the uncertainties in the result of various test items with the deviation values recommended by the European Joint Research Center (EC-JRC), the feasibility of the relevant of testing method was analyzed and evaluated.Results:The uncertainty in epithermal neutron fluence rate was 2.7%. The uncertainty in ratio of thermal to epithermal neutron fluence rate was 3.1%. The uncertainty in ratio of fast neutron air kerma to epithermal neutron fluence rate was 9.3%. The uncertainty in ratio of gamma air kerma to epithermal neutron fluence rate was 8.7%. The uncertainty in spatial distribution of neutron fluence rate was 2.7%. The uncertainty in thermal neutron fluence rate in phantom was 1.8%. The uncertainty in neutron and gamma-ray dose rate in phantom was 17.1% and 4.0%, respectively.Conclusions:The uncertainty in neutron dose rate measurement result in phantom is higher, and further research is needed to improve the accuracy of the testing method. The uncertainty in the measurement result of other test items is lower, and the accuracy of the test result is expected to meet the allowable deviation value recommended by the European Joint Research Center, and the test method is feasible.

ObjectiveTo analyze the characteristics of death and premature death of 4 major chronic diseases （cardiovascular and cerebrovascular diseases， malignant tumors， chronic respiratory diseases and diabetes） in Taizhou City from 2011 to 2018，and provide data basis for the government to formulate chronic disease prevention planning. MethodsThe death data of household registration residents in Taizhou City from 2011 to 2018 were derived from the Chronic Disease Surveillance Information Management System in Zhejiang Province. The death toll ratio of chronic diseases， the mortality rate of chronic diseases， the probability of premature death of chronic diseases were analyzed. The standardization rate was calculated six times in 2010. Population composition of the census. The Joinpoint Regression Program 4.2 software was used for calculating annual percent change （APC） and its statistical test results. ResultsFrom 2011 to 2018， there were 231 724 chronic disease deaths in Taizhou City， with a mortality rate of 486.52/10⁵ and a standardized mortality rate of 381.55/10⁵. The proportion of chronic disease deaths to total deaths was 79.89%， of which males were higher than females and rural areas were higher than urban areas.From 2011 to 2018， the standardized mortality and early death probability of cardiovascular and cerebrovascular diseases， malignant tumors and chronic respiratory diseases in Taizhou showed a downward trend （P<0.05）， the standardized mortality of diabetes （P=0.46） and the early death probability （P=0.22） did not decline， and the mortality of all age groups of the above four types of chronic diseases in rural areas was higher than that in urban areas. The mortality of the four types of chronic diseases from high to low are cardiovascular and cerebrovascular diseases， malignant tumors， chronic respiratory diseases and diabetes， and the mortality tends to increase with age. From 2011 to 2018， the probability of premature death from four types of chronic diseases in Taizhou City showed a downward trend， from 13.49% in 2011 to 10.49% in 2018， with an average annual decrease of 2.97%. The difference was statistically significant （t=‒5.83，P<0.05）. ConclusionChronic disease death is the main cause of death in Taizhou City. In order to reduce the mortality rate of chronic diseases， effective prevention and control measures for chronic diseases should be carried out， especially the prevention and control of diabetes and male chronic diseases.