Objective To reduce the cancer burden in the Jinchang cohort and provide evidence for developing cancer prevention strategies and performing effectiveness evaluation in the Jinchang cohort.We are fitting thirteen years of cancer mortality data from the Jinchang cohort by using six kinds of predicting methods to compare relative fitness and to select good predicting methods for the prediction of cancer mortality trends.Methods The mortality data of cancer in Jinchnag cohort from 2001-2013 were fitted using six kinds of predicting methods:dynamic series,linear regression,exponential smoothing,autoregressive integrated moving average (ARIMA) model,grey model (GM),and Joinpoint regression.Weight coefficients of combination models were calculated by four methods:the arithmetic average method,the variance inverse method,the mean square error inverse method,and the simple weighted average method.Results The cancer mortality was fitted and compared by using six kinds of forecasting methods;the fitting precision of the Joinpoint linear regression had the highest accuracy (87.64％),followed by linear regression (87.32％),the dynamic series (86.99％),GM (1,1) (86.25％),exponential smoothing (85.72％) and ARIMA (1,0,0) (81.98％),respectively.Prediction accuracy of the combination model derived from GM (1,1) and linear regression (＞99％) was higher than that of the combination model derived from ARIMA (1,0,0) and GM (1,1).The combination model derived from the GM (1,1) and linear regression,with weight coefficients based on the arithmetic average method and the mean square error inverse method,had the best prediction effect of the four weight calculation methods.Conclusion Prediction accuracy of the combination model,with accuracy ＞95％,was higher than that of the single prediction methods.

Objective To investigate the effects of simulated 7 500 high altitude on the changes of such related indicators as heart rate variability (HRV),heart rate (HR),respiratory rate,body surface temperatures (BST),arterial oxygen saturation (SaO2) and blood pressure (BP) of the aviators flying 3 different types of aircraft.Methods Forty-nine aviators were chosen as research subjects,and were divided into 3 groups in accordance with the different types of aircraft they flew.Changes in HRV and other vital signs were observed in the aviators flying 3 different types of aircraft.Results As compared with that before hypoxia exposure,HR and BST of the aviators flying different types of aircraft were significantly increased,3 minutes after exposure to hypoxia (P ＜ 0.01),while SaO2 was significantly decreased (all P ＜ 0.01),and respiratory frequency was also decreased (P ＞ 0.05).Before exposure,the values of low frequency (LF),high frequency (HF) and total power (TP) of the aviators flying bombers were all obviously higher than those after exposure (P ＜ 0.05).The LF value before hypoxia was significantly higher than that of the aviators flying transports (P ＜ 0.05).Both before and after hypoxia,body surface temperature of the aviators flying fighters [(32.05 ± 1.16) 、(32.69 ±0.87)℃] was all significantly higher than that of the aviators flying bombers [(30.45 ± 2.13)、(31.76 ± 1.05) ℃] (P ＜ 0.05).Following exposure to hypoxia,the maximum A and minimum mean HRB difference of the aviators flying fighters was significantly higher than that before hypoxia exposure (P ＜ 0.01).Following exposure to hypoxia,the maximum mean respiratory rate of the aviators flying fighters was obviously decreased (P ＜ 0.05),and the maximum and minimum mean respiratory rate difference of the aviators was significantly lower than that before hypoxia exposure (P ＜ 0.05).Conclusions Following hypoxia for 3 minutes at a simulated altitude of 7 500 meters,HR and BST of the aviators in the 3 groups were all increased,SaO2 and respiratory rate were decreased,but BP was not significantly increased.There were variable differences in vital signs and HRV for the aviators flying different types of aircraft.

Objective To investigate the effects of simulated 7 500 high altitude on the changes of such related indicators as heart rate variability (HRV),heart rate (HR),respiratory rate,body surface temperatures (BST),arterial oxygen saturation (SaO2) and blood pressure (BP) of the aviators flying 3 different types of aircraft.Methods Forty-nine aviators were chosen as research subjects,and were divided into 3 groups in accordance with the different types of aircraft they flew.Changes in HRV and other vital signs were observed in the aviators flying 3 different types of aircraft.Results As compared with that before hypoxia exposure,HR and BST of the aviators flying different types of aircraft were significantly increased,3 minutes after exposure to hypoxia (P ＜ 0.01),while SaO2 was significantly decreased (all P ＜ 0.01),and respiratory frequency was also decreased (P ＞ 0.05).Before exposure,the values of low frequency (LF),high frequency (HF) and total power (TP) of the aviators flying bombers were all obviously higher than those after exposure (P ＜ 0.05).The LF value before hypoxia was significantly higher than that of the aviators flying transports (P ＜ 0.05).Both before and after hypoxia,body surface temperature of the aviators flying fighters [(32.05 ± 1.16) 、(32.69 ±0.87)℃] was all significantly higher than that of the aviators flying bombers [(30.45 ± 2.13)、(31.76 ± 1.05) ℃] (P ＜ 0.05).Following exposure to hypoxia,the maximum A and minimum mean HRB difference of the aviators flying fighters was significantly higher than that before hypoxia exposure (P ＜ 0.01).Following exposure to hypoxia,the maximum mean respiratory rate of the aviators flying fighters was obviously decreased (P ＜ 0.05),and the maximum and minimum mean respiratory rate difference of the aviators was significantly lower than that before hypoxia exposure (P ＜ 0.05).Conclusions Following hypoxia for 3 minutes at a simulated altitude of 7 500 meters,HR and BST of the aviators in the 3 groups were all increased,SaO2 and respiratory rate were decreased,but BP was not significantly increased.There were variable differences in vital signs and HRV for the aviators flying different types of aircraft.