Study on air temperature estimation and its influencing factors in a complex mountainous area.

Near-surface air temperature (Ta) is an important parameter in agricultural production and climate change. Satellite remote sensing data provide an effective way to estimate regional-scale air temperature. Therefore, taking Gansu section of the upper Weihe River Basin as the study area, using the filtered reconstructed high-quality long-time series normalized difference vegetation index (NDVI), interpolated reconstructed land surface temperature (LST), surface albedo, and digital elevation model (DEM) as the input data, the back-propagation artificial neural network algorithm (BP-ANN) was combined with a multiple linear regression method to estimate regional air temperature, and the influencing factors of air temperature estimation were analyzed. This method effectively compensates for the fact that air temperature data provided by a single station cannot represent regional air temperature information. The result shows that the temperature estimation accuracy is high. In terms of interannual variation, the air temperature in the study area showed a slightly increasing trend, with an average annual increase of 0.047°C. The calculation results of the interannual variation rate of temperature showed that the area with increased air temperature accounted for 75.8% of the total area. In terms of seasonal variation, compared with that in summer and winter, the air temperature rising trend in autumn was obvious, and the air temperature in the middle of the study area decreased in spring, which is prone to frost disasters. LST and NDVI in the study area were positively correlated with air temperature, and their positive correlation distribution areas accounted for 93.62% and 94.34% of the total study area, respectively. NDVI, LST and DEM influence the temperature change in the study area. The results show that there is a significant positive correlation between NDVI and air temperature, and the change of NDVI has a positive effect on the spatiotemporal variation of air temperature. The correlation coefficient between LST and air temperature in the southeast of the study area is negative, and there is a difference. In addition, the correlation coefficient between LST and air temperature in other areas of the study area is positive. The air temperature decreased with elevation, air temperature decreases by 0.27°C every hundred meters.

Analysis of the situation of pre-pregnancy health check in rural areas of Sichuan province / 重庆医学

Objective To investigate the situation of pre-pregnancy health check in rural areas of Sichuan province and get the key difficult points during the process of carrying out the work.Methods According to the economic situation in Sichuan province and geographic distribution,random eight areas in Sichuan province (Chengdu,Neijiang,Nanchong,Ziyang,Meishan,Zigong,Les-han and Suining),investigate pregnant women in maternal and child health care institutions and family planning service institutions at all all levels in the areas above.Results Only 334 people (33.26%)underwent the pre-pregnancy health check during the 974 pregnant women in rural areas.The rate of planned pregnancy is low;the rate of unintended pregnancy is close to 40.00%.55.29%of the planned pregnancy women didn′t undergo the pre-pregnancy health check.And the factors that affect their behavior of under-going pre-pregnancy health check are whether planned pregnancy and personal attitude towards pre-pregnancy health check.Conclu-sion The rate of pre-pregnancy health check is low in the pregnant women from rural areas of Sichuan province,the health sector needs to make efforts to promote and enhance the awareness of the rural pregnant women to prevent birth defects and the initiative in participation.

The study on college students' security and its influencing factors / 中华行为医学与脑科学杂志

Objective To develop the security scale of college students' sense to investigate college students' subjective feeling of security.According to the characteristics of the feeling tendentiousness to analysis the subject and object factors influencing the insecurity of college students.Methods The security scale of college students' sense compiled was administrated to 500 college student randomly stratified cluster sampling from four universities in Yantai,then description and analysis were analyzed by SPSS17.0,AHP and SAS9.1 to statistical.Results Through the scale of exploratory factor analysis,the Cronbach' s of the scale was 0.629.College students in four dimensions of security and total security were in above-average levels,college students' total scorc of security is significance of difference in grade,gender and whether come from the single parent(all P＜0.05) ;Self security was significance of difference in the grade and the gender(P＜0.01 and P＜0.05) ; and interpersonal security in gender and whether come from the single parent had significance difference(P＜0.05) ;Determine control and family security in these demographic variable aspects had no significant differences.Multivariate factors analysis results showed that the decision tree model was better than the logistic model (the misclassification rate of the model was lower than the decision tree model).The main factors affecting the university students' security were gender,grade,the average income and whether they,were the only children.The misclassification rate of the decision tree model was lower than the model of logistic.College students' sense of dimensions are significant with positive correlation,the dimension of the security level may affect other security of the situation.Conclusion The security scale of college students' sense has good reliability and validity and can be used in the study of college security.The factor analysis determines it can be used multiple factors analysis.The survey shows that the overall security of the crowd' s is over the average level.The gender,grade,annual per-capita income and whether the one-child are the potential factors that affect college students' insecurity.