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Background Dental caries have a serious impact on general health and well-being; however, there is a lack of relevant data on the development trends of dental caries in permanent teeth among 12-year-old children in China. We aim to assess long-term trends of dental caries in permanent teeth among 12-year-old children in China and identify the susceptible subgroups based on five consecutive national surveys from 1995 to 2014. Methods A total of 88 972 subjects were extracted from five consecutive national surveys (1995, 2000, 2005, 2010, 2014). Standardized dental examinations were conducted and the oral health status of each subject was recorded. The prevalence of Decayed, Missing and Filled teeth (DMF%), mean Decayed, Missing, Filled teeth score (DMFT) and Caries Filling Ratio (CFR) were used as measurement indicators. Cochran–Armitage trend test was used to evaluate the trends in DMF% and CFR, and multivariate linear regression was used to evaluate the trends in DMFT. Results A V-shaped fluctuating upward trend in DMF% during 1995–2014 was observed (Z = − 13.124, P β = 0.057, P P > 0.05), and the CFR in 1995–2014 was 17.4%, 22.8%, 19.3%, 23.4% and 15.6%. The DMF% and DMFT of rural children had a larger absolute increase than that of urban children during 1995–2014 (DMF%-urban: Z = − 0.242, P > 0.05; DMF%-rural: Z = − 19.036, P β = 0.035, P β = 0.077, P (P (P Conclusions Over the past 20 years, DMFT and DMF% of 12-year-old children in China presented V-shaped fluctuant upward trends, with a decline trend from 1995 to 2000 and an upward trend from 2000 to 2014. CFR had no significant improvement. The rural children and girls are the more vulnerable groups in the development of dental caries and need to pay priority. Our study supports the continuation of policies to improve children’ oral health.

ObjectivesWe used data from the China Health and Retirement Longitudinal Study (CHARLS) to investigate how an early life famine exposure affected possible sarcopenia (PS) and to explore the extent to which a sex difference exists in the association among older Chinese adults, as well as whether risk factors modify the association.DesignCross-sectional study.Setting28 provinces of China.ParticipantsConsidering that the Great Chinese Famine lasted from the spring of 1959 to the fall of 1961, 3557 participants were selected and categorised into four subgroups based on their date of birth: unexposed group (1 October 1962 to 30 September 1964), fetal exposed group (1 October 1959 to 30 September 1961), infant exposed group (1 January 1958 to 31 December 1958) and preschool exposed group (1 January 1956 to 31 December 1957).Outcome measurePS was defined as having low muscle strength or low physical performance.MethodsWe used multivariable logistic models to analyse the association between early life famine exposure and the risk of PS in elderly life.ResultsThe prevalences of PS among individuals in the unexposed, fetal, infant and preschool exposed groups were 15.1%, 14.4%, 23.6% and 21.9%, respectively. Compared with the unexposed group, the infant (OR: 1.55; 95% CI 1.17 to 2.05) and preschool exposed (OR: 1.46; 95% CI 1.17 to 1.82) groups exhibited significantly higher risks of PS. In men, the infant (OR: 2.15; 95% CI 1.40 to 3.31) and preschool exposed (OR: 1.78; 95% CI 1.23 to 2.57) groups were more likely to have PS, but no significant increase was seen in women. In both sexes, prevalence of PS was unrelated to early life famine exposure in the urban, underweight and normal weight subgroups.ConclusionsEarly life exposure to the Great Chinese Famine was associated with a higher risk of PS in older adults. Keeping normal nutritional status in elderly life might help avoid the risk of PS, whatever the effect of early famine exposure.

Summary Background Early marriage and fertility are major social determinants of health and wellbeing. Rapid shifts in the past three decades, including a rise in sexual activity in unmarried adolescents, a large population of young migrant workers, and a high proportion of males relative to females, have the potential to alter patterns of reproductive health in Chinese adolescents and young women. We aimed to establish long-term trends of marriage and fertility for girls and women aged 15–24 years in China. Methods We did a longitudinal study in which we extracted aggregated data for marriage and childbearing status for Chinese girls and women aged 15–24 years from the Chinese National Population Census (in 1990, 2000, and 2010) and the Chinese 1% National Population Sample Survey (in 1995, 2005, and 2015). The census included all individuals with Chinese nationality who resided in China when the survey was done. For the 1% sample survey, communities or villages were randomly selected and all residents with Chinese nationality in the selected communities or villages were included. In all censuses and sample surveys, forms that included information on basic demographic characteristics, education, marriage, and fertility were completed and verified by the census enumerators at the household residence, based on responses provided by the householder or another adult in the household. We calculated the ever-married rate and age-specific fertility rate (ASFR) for all included individuals. We built multivariate random-effects generalised least squares regression models on panel data to test whether marriage or fertility rate was associated with education level, sex ratio, and the proportion of the population who are an ethnic minority in a province. Findings The ever-married rate for those aged 15–19 years decreased from 4·7% in 1990 to 1·2% (95% CI 1·2–1·3) in 2000, but rebounded to 2·4% (2·4–2·5) in 2015. The ASFR for this age group decreased from 22·0 births per 1000 individuals in 1990 to 6·0 (5·9–6·0) births per 1000 in 2000, and rebounded to 9·2 (8·9–9·4) births per 1000 in 2015. The rebound was found in most provinces. In women aged 20–24 years, the ever-married rate generally declined from 58·6% in 1990 to 25·5% (95% CI 25·4–25·6) in 2015, and the ASFR decreased from 198·8 births per 1000 in 1990 to 55·0 (54·5–55·5) births per 1000 in 2015. In 2015, the ever-married rate and ASFR for girls and women in rural areas aged 15–19 years were three-times higher than those of their urban counterparts (3·8% [95% CI 3·7–3·9] vs 1·1% [1·1–1·1] for the ever-married rate and 15·4 [14·9–15·9] vs 4·1 [3·9–4·3] births per 1000 for the ASFR). There were large disparities in ever-married rate across individuals of different education levels, with increases in the ever-married rate of 15–19-year-olds not attending senior high school between 2000 and 2010. Those aged 15–19 years were more likely to be married or give birth in the western provinces. Education held a protective association against adolescent childbearing, whereas a high ratio of males to females and a high proportion of ethnic minorities were associated with greater risk. Interpretation Although China's total fertility rate remains far less than replacement, after a period of steady decline, there has been a rebound in adolescent marriage and childbearing in the past decade. A range of adolescent-targeted strategies will be needed across provinces, including scaling up comprehensive sex education, ensuring that girls continue in school, and providing adequate reproductive health services, which specifically meet the needs for modern contraception in sexually active unmarried girls. Funding Humanities and Social Sciences Planning Fund Project, Sports and Health Special Project of Education and Scientific Research, and China Scholarship Council.

The core carrier working substances of heat accumulation of solar thermal generator units are analyzed through computer numerical simulation analysis and simulation experiments, including the selection criteria of working substances, the mechanism of heat accumulation system, the correlation between power generation efficiency and the evaporation temperature of working substance, the correlation between the condensing temperature and condensing pressure of working substance, and the influence of working substance velocity on heat accumulation capacity. The results show that under the same radiation intensity, the greater the flow velocity of the working substance is, the worse the heat accumulation and heat conduction of the working substance is. As the condensing temperature of the working substance increases, the condensing pressure also increases. As the evaporation temperature of the working substance increases, the power generation efficiency of the working substance also increases significantly. In summary, the heat accumulation system based on the high efficiency working substances is vital for the normal operation of solar thermal generator units. Once the solar radiation intensity cannot meet the needs of power generation, the heat accumulation system will output previously-stored thermal energy. Meanwhile, its collection and release of thermal energy depend on the photovoltaic intensity. The constructed hot-oil working substance-based heat accumulation system satisfies the normal operation needs for thermal generator units, which is significant for subsequent research.

Background: Evidence in adults suggests that exposure to artificial light-at-night (ALAN) leads to obesity. However, little is known about whether this effect exists in children and adolescents. We aimed to investigate whether ALAN exposure was associated with overweight and obesity in school-aged children and adolescents and whether this association varied with socioeconomic status. Methods: Data on the height and weight of 129,500 children and adolescents aged 10–18 years from 72 cities were extracted from the 2014 Chinese National Survey on Students’ Constitution and Health (CNSSCH). The ALAN area percentage and average ALAN intensity were calculated using the Visible/Infrared Imager/Radiometer Suite. The subjects were separated into three categories based on the cities’ gross domestic product per capita (GDPPC). A mixed-effect logistic regression model and generalized additive model (GAM) were utilized to evaluate the association between ALAN exposure and overweight and obesity in children and adolescents stratified by municipal GDPPC. Results: Both ALAN area (OR = 1.194, 95% CI: 1.175–1.212) and ALAN intensity (OR = 1.019, 95% CI: 1.017–1.020) were positively associated with overweight and obesity in children and adolescents, and the associations remained robust after adjusting for covariates. ORs for overweight and obesity and ALAN area decreased as GDPPC level increased (first tertile: OR = 1.457, 95% CI: 1.335–1.590; second tertile: OR = 1.350, 95% CI: 1.245–1.464; third tertile: OR = 1.100, 95% CI: 1.081–1.119). Similar results were observed for ALAN intensity. In the GAM models, thresholds existed in almost all these spline trends, indicating that ALAN might have a nonlinear association with overweight and obesity. Conclusions: ALAN contributed to the development of overweight and obesity in children and adolescents and this effect differed with GDPPC. Future longitudinal studies should confirm the causal relationship between ALAN and obesity. Moreover, reducing unnecessary exposure to artificial light at night may have beneficial implications for controlling childhood and adolescent obesity, particularly in low-income areas.

Due to the fast phase separation kinetics and small feature size, the self-assembly of giant molecules has attracted lots of attention. However, there is not much study on multicomponent giant surfactants. In this work, through a modular synthetic strategy, different polyhedral oligomeric silsesquioxane (POSS)-based molecular nanoparticles are installed with diverse functionalities (hydrophobic octavinyl POSS (VPOSS), hydrophilic dihydroxyl-functionalized POSS (DPOSS), and omniphobic perfluoroalkyl-chain-functionalized POSS (FPOSS)) on the ends of one polystyrene (PS) chain to build up a series of triblock bola-form giant surfactants denoted as XPOSS-PS

Phytochemicals, especially flavonoids, have been widely investigated for their diversified pharmacological activities including anticancer activities. Previously we identified isoangustone A from licorice-derived compounds as a potent inducer of cell death. In the present study, the exact mechanism by which isoangustone A induced cell death was further investigated, with autophagy as an indispensible part of this process. Isoangustone A treatment activated autophagic signaling and induced a complete autophagic flux in colorectal cancer cells. Knockdown of ATG5 or pre-treatment with autophagy inhibitors significantly reversed isoangustone A-induced apoptotic signaling and loss of cell viability, suggesting autophagy plays an important role in isoangustone A-induced cell death. Isoangustone A inhibited Akt/mTOR signaling, and overexpressing of a constitutively activated Akt mildly suppressed isoangustone A-induced cell death. More importantly, isoangustone A inhibited cellular ATP level and activated AMPK, and pre-treatment with AMPK inhibitor or overexpression of dominant negative AMPKα2 significantly reversed isoangustone A-induced autophagy and cell death. Further study shows isoangustone A dose-dependently inhibited mitochondrial respiration, which could be responsible for isoangustone A-induced activation of AMPK. Finally, isoangustone A at a dosage of 10 mg/kg potently activated AMPK and autophagic signaling in and inhibited the growth of SW480 human colorectal xenograft in vivo. Taken together, induction of autophagy through activation of AMPK is an important mechanism by which isoangustone A inhibits tumor growth, and isoangustone A deserves further investigation as a promising anti-cancer agent.

Background Self-harm and drinking are both serious problems in adolescents and many studies presented evidence of their association. However, gender differences in this association are seldom deeply discussed. Our study aimed to evaluate the prevalence of self-harm and explore its association with drinking behaviors by gender and investigate the extent to which the gender differences exist in the association between self-harm and drinking. Methods A total of 32,362 students in grades 7 to 12 in Beijing, China were anonymously surveyed and included in our study using two-stage, stratified probability proportion sampling. Self-harm, drinking behaviors and other basic information were obtained from an anonymous questionnaire. Demographic variables, self-harm and drinking behaviors were analyzed using the Chi-square test and the Gamma test between genders and the gender differences in this association were analyzed by Log-binomial regression. Results The total prevalence of self-harm was 13.7% with no significant gender difference (χ2 =0.352, P = 0.553). The prevalence of self-harm in girls decreased with age (G = -0.163, P Conclusion Among high school students, self-harm has a significant positive association with drinking and girls with drinking behaviors are at higher risk of suffering self-harm. Identifying adolescents’ drinking behaviors is of vital importance to self-harm prevention and special attention should be focused on younger girls.

Economic growth has brought improvements in many areas of child health, but its effects on anaemia among school‐aged children remain unknown. However, this is important because iron deficiency anaemia is common and is the main cause of disability‐adjusted life years for school‐aged children. In this study, we included 429,222 Chinese children aged 7–17 years from five consecutive national cross‐sectional surveys during 1995–2014. Using altitude‐adjusted haemoglobin concentration measured from capillary blood samples, we defined anaemia status according to World Health Organization's recommendation. We used logistic regressions weighted by provincial population to examine the association between provincial gross domestic product (GDP) per capita and anaemia, adjusting for sex, age, urban–rural location, regional socio‐economic status (SES), fixed effect of province, and clustering of schools. We used generalised additive mixed models to evaluate a potentially non‐linear relationship. For each 100% growth in GDP per capita, there was a 40% (odds ratio [OR] = 0.60; 95% confidence interval [CI; 0.56, 0.65]) reduction in anaemia. However, the association was weaker for girls and in cities with a lower SES. The association was weaker across 2005–2014 (OR = 0.75, 95% CI [0.62, 0.90]) compared with 1995–2005 (OR = 0.52; 95% CI [0.44, 0.61]), reflecting a weaker association when GDP per capita reaches around $2,000. The results were similar for moderate‐to‐severe anaemia. We concluded that economic growth has been associated with reductions in anaemia among school‐aged children in China but with fewer benefits for girls and those in poorer settings. Further economic development in China is unlikely to bring similar reductions in anaemia, suggesting that additional population level and targeted interventions will be needed.

Aim This study assessed the trends in the age at menarche in Chinese schoolgirls from the majority Han group and 21 ethnic minorities from 2005 to 2014. We also compared the group differences during the study period. Methods A total of 344 230 girls aged 9-18 years were extracted from the 2005, 2010 and 2014 Chinese National Survey on Students' Constitution and Health. The age at menarche for each subgroup was estimated by probit analysis. The chi-square test and Z-test were used to compare the differences between the groups. Results The overall average age at menarche in Chinese schoolgirls decreased from 12.8 years in 2005 to 12.3 years in 2014. The Han girls and girls from 17 ethnic minorities showed decreasing trends in the age at menarche, while four ethnic minorities demonstrated fluctuating increasing trends over time. The gaps in age at menarche between the Han group and 14 of the ethnic minorities became smaller over the study period and were similar by 2014. Conclusion The overall findings were a decrease in the age at menarche in China and smaller gaps between the majority Han group and ethnic minority groups. Ethnic-specific public health policies are urgently needed on issues such as contraception.

Charging-station provides power supply for electric vehicles, which is a necessary and important energy supporting infrastructure for development and large scale commercialization operation of electric.For the current charging-station management is overly dependent on high-cost devices such as industrial computer, this paper develops a charger field test device, which adopts STM32 as the data exchange interface between the host computer and charger. The charge data is sent to PC through STM32, and the monitoring system development is designed by LABVIEW.This method optimizes the decoding of message content, overcomes the defect of over reliance on high cost components, and strengthenes the ability of bottom message collection, enhances the system intelligence.The communication is fast, reliable and has a good man-machine interface.

In our country, gas-fired has been widely applied to the residents and the life. All reasons of gas leaks cause personal injury and property damage. And those cause huge energy waste. The current gas leaks detector in family is single alarm function, at the same time it is not widely used. To solve these problems, paper designed a gas leaks automatic detection and processing device by using the Fujitsu MB95204K. The device through the indoor corresponding gas concentration measurement and the concentration of the gas software installed state threshold ways to judge whether to make the each level operation. In order to overcome the shortcomings of current single alarm function device. Device has LIN-UART interface expanding for the future wireless upgrade. It is convenient to use ZIGBEE etc wireless technology to compose intelligent monitoring net, intelligent household and a net node in The Internet of things.