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Objective:To analyze the long-term trend of viral hepatitis mortality in Jing’an District of Shanghai， and to provide a reference for viral hepatitis prevention and control. Methods:Mortality rate， standard mortality rate， PYLL and potential years of life lost rate （PYLL‰） of viral hepatitis in Jing’an district of Shanghai from 1976 to 2015 were calculated. The annual percent change （APC） of the mortality and PYLL‰ were analyzed by Joinpoint regression analysis. Results:From 1976 to 2015， there were 1 342 viral hepatitis death cases， including 832 males and 510 females. The average crude mortality rate was 8.31/100 000， and the average age-standardized mortality rate was 5.45/100 000. Among the deaths of viral hepatitis， men had a higher mortality rate， age-standardized mortality rate and PYLL% than women （χ2Pearson=107.34， 112.93， 39.15， all P<0.01）， men were mainly in the age group of 35-64 years （accounted for 62.62%）， while women were mainly in the age group of 65 years and above （accounted for 55.49 %）， and the average death age of men was earlier than that of women （by rank-sum test： Z=-8.879，P<0.01）. After 1990 （except in 2002）， hepatitis B was the main cause of deaths from viral hepatitis， accounting for 75.00%-100%， and the proportion of other and unclassified cases gradually decreased. Overall， the mortality rate of viral hepatitis declined significantly during 1976-2015 （APC=-2.0%，P<0.05）， with the turning point in 2002. The mortality rate of viral hepatitis declined significantly from 2002 to 2015 （APC=-8.1%，P<0.05）. The overall PYLL‰ of viral hepatitis declined significantly during 1976-2015 （APC=-3.7%，P<0.05）， with the turning point in 1992. After 1992， the PYLL‰ of viral hepatitis declined significantly during 1992-2015 （APC=-6.5%，P<0.05）. Conclusion:There has been a significant decline trend of viral hepatitis in the mortality rate in Jing’an District of Shanghai from 2002 to 2015， with hepatitis B as the main cause of death.
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The effects of the γâ³-Ni3Nb phase on fatigue behavior of nickel-based 718 superalloys with standard heat treatment, hot isostatic pressing + solution treatment + aging, and hot isostatic pressing + direct aging were investigated by scanning electron microscope, transmission electron microscopy, and fatigue experiments. The standard heat treatment, hot isostatic pressing + solution treatment + aging, and hot isostatic pressing + direct aging resulted in the formation of more and smaller γⳠphases in the matrix in the nickel-based 718 superalloys. However, the grain boundaries of the hot isostatic pressing + direct aging sample showed many relatively coarse disk-like γⳠphases with major axes of ~80 nm and minor axes of ~40 nm. The hot isostatic pressing + direct aging sample with a stress amplitude of 380 MPa showed the longest high cycle fatigue life of 5.16 × 105 cycles. Laves phases and carbide inclusions were observed in the crack initiation zone, and the cracks propagated along the acicular δ phases in the nickel-based 718 superalloys. The precipitation of fine γⳠphases in the matrix and relatively coarse γⳠphases in the grain boundaries of the hot isostatic pressing + direct aging sample can hinder the movement of dislocation.
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The effects of the γâ³-Ni3Nb phase on the mechanical properties of Inconel 718 superalloys, with standard heat treatment, hot isostatic pressing + solution treatment + aging, and hot isostatic pressing + direct aging, were characterized by morphological observation, X-ray diffraction, and tensile experiments. The results of the morphological observation revealed that many fine γⳠprecipitates of ~26.49 ± 1.82 nm in mean size were formed in all samples. However, the relatively coarser γⳠprecipitates formed in the grain boundaries were only observed in the sample treated with hot isostatic pressing + direct aging. The yield strengths of the hot isostatic pressing + direct aging sample at room temperature and at 650 °C both exhibited the maximum values about 993 ± 5.7 and 811 ± 12.6 MPa, respectively. The γⳠprecipitate was considered to be the dominant strengthening phase in the sample according to the lattice misfits (ε) of γ/γâ³. The strengthening mechanism of the samples can be explained as the coherency strain strengthening of fine γⳠprecipitates. Moreover, due to the coarser γⳠprecipitates in the grain boundaries, dislocation-cut ordered particle strengthening also occurred in the sample after hot isostatic pressing + direct aging treatment.
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Objective To investigate the impact of early health status on the risk of developing child overweight and obesity so as to provide evidences for preventive measures against child overweight and obesity.Methods Three schools were randomly selected from primary schools in Shanghai, and another three schools were randomly selected from 9-year schools in Shanghai.Retrospective surveys were conducted for 1 511 pupils selected from all the Grade One and Grade Two students of the above selected schools, the univariate and multivariate logistic regression analyses were used to analyze the early risk factors for child overweight and obesity.Results The results of univariate logistic regression analyses showed that for the children with relatively high birth weights, asthma, allergic constitution, histories of chronic diseases, relatively good appetite, relatively high ages that had been notified of their overweight and obesity, the detection rate of overweight and obesity was higher (P<0.05).The results of multivariate logistic regression analyses showed that birth weights(OR=2.699, 95%CI=1.097~6.644), allergic constitution(OR=1.498, 95%CI=1.044~2.149), histories of chronic diseases(OR=2.486, 95%CI=1.327~4.659) and appetite(OR=22.011, 95%CI=8.861~54.673) were the risk factors influencing child overweight and obesity (P<0.05).Conclusion Attention still needs to be paid to the body mass control of the children with relatively high birth weights, allergic constitution and histories of chronic diseases.Scientific and reasonable feeding at early stages as well as cultivating good eating and drinking habits may help prevent and control child overweight and obesity.
