Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible rel...Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women.Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured.Results The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels.Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels.展开更多
Objective This study aimed to assess the relationship between the body composition of children aged 3–5 years and breastfeeding status and duration.Methods The study was conducted using data from the National Nutriti...Objective This study aimed to assess the relationship between the body composition of children aged 3–5 years and breastfeeding status and duration.Methods The study was conducted using data from the National Nutrition and Health Systematic Survey for children 0–17 years of age in China(CNHSC),a nationwide cross-sectional study.Breastfeeding information and potential confounders were collected using standardized questionnaires administered through face-to-face interviews.The body composition of preschool children was measured using bioelectrical impedance analysis.A multivariate linear regression model was used to assess the relationship between breastfeeding duration and body composition after adjusting for potential confounders.Results In total,2,008 participants were included in the study.Of these,89.2%were ever breastfed and the median duration of breastfeeding was 12 months(IQR 7–15 months).Among children aged 3 years,the height-for-age Z-score(HAZ)for the ever breastfed group was lower than that for never breastfed group(0.12 vs.0.42,P=0.043).In addition,the weight-for-age Z-score(WAZ)of the ever breastfed group was lower than that of the never breastfed group(0.31 vs.0.65,P=0.026),and the WAZ was lower in children aged 4 years who breastfed between 12 and 23 months than in those who never breastfed.Compared to the formula-fed children,the fat-free mass of breastfed infants was higher for children aged 3 years(12.84 kg vs.12.52 kg,P=0.015)and lower for those aged 4 years(14.31 kg vs.14.64 kg,P=0.048),but no difference was detected for children aged 5 years(16.40 kg vs.16.42 kg,P=0.910)after adjusting for potential confounders.No significant difference was detected in the weight-for-height Z-score(WHZ),body mass index(BMI)-for-age Z-score(BAZ),fat-free mass index,and body fat indicators in the ever breastfed and never breastfed groups and among various breastfeeding duration groups for children aged 3–5 years.Conclusion No obvious associations were detected between breastfeeding duration,BMI,and fat mass indicators.Future prospective studies should explore the relationship between breastfeeding status and fat-free mass.展开更多
Objective To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013. Methods The study was based on two national surveys. Undernutrition was determined against ...Objective To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013. Methods The study was based on two national surveys. Undernutrition was determined against WHO＇s 2006 growth standards. The prevalence in 2013 and 2002 was weighted by China sixth National Population Census （2010）. The relationship between undernutrition and gender/age groups/different areas use weighted logistic regression. Results The results indicated the overall prevalence of stunting, underweight, and wasting of Chinese children under S-year was 8.1%, 2.4%, and 1.9% in 2013, respectively. The prevalence of stunting was higher for children aged 12-47 month, while underweight was higher for children aged 48-59 month. The prevalence of undernutrition was higher in rural areas than in urban areas, especially in poor rural areas. There was a decline of stunting, underweight, and wasting between 2002 and 2013 among the children, with greater reduction in rural areas than in urban areas. Conclusion The prevalence of undernutrition of children under 5-year remains high in rural areas especially in poor rural areas in China. It is urgent to take action to control undernutrition in the vulnerable areas and subgroups.展开更多
Objective The primary objective of this study was to examine the validity and reliability of a semi-quantitative food frequency questionnaire(FFQ) among Chinese children aged 12-17 years. Methods A semi-quantitative 7...Objective The primary objective of this study was to examine the validity and reliability of a semi-quantitative food frequency questionnaire(FFQ) among Chinese children aged 12-17 years. Methods A semi-quantitative 72-food item FFQ was developed for children aged 12-17 years. The reliability and validity of this FFQ were evaluated against 24-h dietary recalls(24 h DRs) to measure the consumption of foods and nutrients. We administered two FFQs and three DRs to children(N = 160) over a period of 1 month to evaluate the reliability and validity. Reliability was examined by quartile agreement and intraclass correlation coefficients(ICCs), and validity was examined by quartile agreement, Bland-Altman plots and correlation with DRs. Results For reliability, the ICCs between the two FFQs ranged from 0.21 to 0.76 for foods and nutrients, and the quartile agreement ranged from 70.0% to 95.0% in the same or adjacent quartiles. Spearman’s correlation coefficients of foods and nutrients between the second FFQ and the 24 h DRs ranged from-0.04 to 0.59. The Bland-Altman plots demonstrated good agreement across the range of intakes among nutrients. The quartile agreement ranged from 50.0% to 100.0%, with infrequent misclassification. Conclusion The FFQ assessment of dietary intakes demonstrated acceptable relative validity and high reproducibility for Chinese children aged 12-17 years.展开更多
Objective This study is aimed to report the development,the reliability and validity of the Chinese Children Physical Activity Questionnaire(CCPAQ)which was designed for the assessment of physical activity pattern in ...Objective This study is aimed to report the development,the reliability and validity of the Chinese Children Physical Activity Questionnaire(CCPAQ)which was designed for the assessment of physical activity pattern in young population in China.Methods The CCPAQ was administered for two times in 119 children(mean age 13.1±2.4 years;boys 47%)to examine reliability by using intraclass correlation coefficients.Validity was determined in 106 participants by agreement with the CCPAQ measures and the objective method,the ActiGraph accelerometer.Data on physical activity patter n including time spe nt on d iff ere nt intensi ties and total physical activity,sedentary behavior as well as physical activity energy expenditure were used to assess the validity with Spearman's correlation coefficient and the Bland-Altman plots.Results The reliability coefficient of the CCPAQ ranged from 0.63-0.93(Intra-class correlation coefficient).Spearman's correlation coefficient for validity of time spent on total physical activity and sedentary behavior were all 0.32(P<0.001),and for physical activity energy expenditure was 0.58(P<0.001).Time spent on moderate-to-vigorous physical activity and light physical activity showed a relatively low correlation with the accelerometer(rho=0.20,P=0.040;rho=0.19,P=0.054).Conclusion The CCPAQ appears to be a promising and feasible method to assess physical activity pattern in Chinese children.展开更多
The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China(CNHSC)was to collect basic data on the nutrition,development,and health status for children in different ...The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China(CNHSC)was to collect basic data on the nutrition,development,and health status for children in different regions across China using evidence-based,reliable,and cost-effective approaches.Children and their parents or guardians from seven regions(south,southwest,north,northwest,eastern,central,and northeast China)in China were recruited.A multi-stage stratified randomized sampling method was used.Two provinces were randomly sampled from each of the seven regions,from which one urban district and one rural country were also randomly sampled,resulting in a total of 28 survey counties/districts.Dietary surveys,health examinations,laboratory testing,and questionnaires were used to collect dietary intake,nutritional status,child development,and health status information.Nutrition,health,and lifestyle assessment of children and their parents was determined using the Knowledge Attitude Practice(KAP)survey.Greater than 100,000 children(38,000 children<6 years of age and 66,000 children6-17 years of age)completed the survey.The survey provided comprehensive data on child nutrition and health status for future studies and will serve as the basis for an integrated nutrition and health improvement strategies proposal for children in China.展开更多
Objective To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods The pretreated human milk samples were adequately separated and quan...Objective To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column （2.1×100 mm, 1.8 μm）. The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESl＋ionization and detected in multiple reaction monitoring （MRM） with three acquisition functions. Results Calibration curves ranged from 0.5-160 ng/mL （thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal）, and 2.5-800 ng/mL （pantothenic acid, FAD and nicotinamide） （R^2=0.990-0.999）. The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification （LOQ） for all vitamins was between 0.25 and 3 lag/L. Conclusion This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.展开更多
INTRODUCTION Globally,childhood obesity has gradually become prevalent in recent decades.According to estimations by United Nations International Children's Emergency Fund(UNICEF),the World Health Organization(WHO...INTRODUCTION Globally,childhood obesity has gradually become prevalent in recent decades.According to estimations by United Nations International Children's Emergency Fund(UNICEF),the World Health Organization(WHO),and the World Bank,the global prevalence of being overweight for children under 5 years rose from 4.9%in 2000 to 5.6%in 2019[1].The Institute for Health Metrics and Evaluation(IHME)estimated that,between 1980 and 2015,the worldwide proportion of obesity increased from 3.9%to 7.2%and 3.7%to 6.4%in boys and girls aged 2-4 years,respectively121.Meanwhile,the Non-Communicable Diseases Risk Factor Collaboration reported that the global prevalence of obesity rose from 0.9%to 7.8%and 0.7%to 5.6%in boys and girls aged 5-19 years,respectively,between 1975 and 2016[3].Globally,the total number of overweight and obese individuals reached 40 and 340 million in children under 5 years and aged 5-19 years,respectively,in 2016.展开更多
Dislocations are of great importance in revealing the underlying mechanisms of deformed solid crystals.With the development of computational facilities and technologies,the observations of dislocations at atomic level...Dislocations are of great importance in revealing the underlying mechanisms of deformed solid crystals.With the development of computational facilities and technologies,the observations of dislocations at atomic level through numerical simulations are permitted.Molecular dynamics(MD)simulation suggests itself as a powerful tool for understanding and visualizing the creation of dislocations as well as the evolution of crystal defects.However,the numerical results from the large-scale MD simulations are not very illuminating by themselves and there exist various techniques for analyzing dislocations and the deformed crystal structures.Thus,it is a big challenge for the beginners in this community to choose a proper method to start their investigations.In this review,we summarized and discussed up to twelve existing structure characterization methods in MD simulations of deformed crystal solids.A comprehensive comparison was made between the advantages and disadvantages of these typical techniques.We also examined some of the recent advances in the dynamics of dislocations related to the hydraulic fracturing.It was found that the dislocation emission has a significant effect on the propagation and bifurcation of the crack tip in the hydraulic fracturing.展开更多
基金funded by the National Health Commission of People’s Republic of China Medical Reform Major Program‘2016-2017 National Nutrition and Health Surveillance of Children and Lactating Women’Major Public Health Project‘Survey and Evaluation of Iodine Nutrition and Thyroid Diseases of Chinese Population’[131031107000160007].
文摘Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women.Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured.Results The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels.Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels.
基金supported by National Special Program for Science&Technology Basic Resources Investigation of China[Grant Number:2017FY101100 and 2017FY101103]。
文摘Objective This study aimed to assess the relationship between the body composition of children aged 3–5 years and breastfeeding status and duration.Methods The study was conducted using data from the National Nutrition and Health Systematic Survey for children 0–17 years of age in China(CNHSC),a nationwide cross-sectional study.Breastfeeding information and potential confounders were collected using standardized questionnaires administered through face-to-face interviews.The body composition of preschool children was measured using bioelectrical impedance analysis.A multivariate linear regression model was used to assess the relationship between breastfeeding duration and body composition after adjusting for potential confounders.Results In total,2,008 participants were included in the study.Of these,89.2%were ever breastfed and the median duration of breastfeeding was 12 months(IQR 7–15 months).Among children aged 3 years,the height-for-age Z-score(HAZ)for the ever breastfed group was lower than that for never breastfed group(0.12 vs.0.42,P=0.043).In addition,the weight-for-age Z-score(WAZ)of the ever breastfed group was lower than that of the never breastfed group(0.31 vs.0.65,P=0.026),and the WAZ was lower in children aged 4 years who breastfed between 12 and 23 months than in those who never breastfed.Compared to the formula-fed children,the fat-free mass of breastfed infants was higher for children aged 3 years(12.84 kg vs.12.52 kg,P=0.015)and lower for those aged 4 years(14.31 kg vs.14.64 kg,P=0.048),but no difference was detected for children aged 5 years(16.40 kg vs.16.42 kg,P=0.910)after adjusting for potential confounders.No significant difference was detected in the weight-for-height Z-score(WHZ),body mass index(BMI)-for-age Z-score(BAZ),fat-free mass index,and body fat indicators in the ever breastfed and never breastfed groups and among various breastfeeding duration groups for children aged 3–5 years.Conclusion No obvious associations were detected between breastfeeding duration,BMI,and fat mass indicators.Future prospective studies should explore the relationship between breastfeeding status and fat-free mass.
文摘Objective To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013. Methods The study was based on two national surveys. Undernutrition was determined against WHO＇s 2006 growth standards. The prevalence in 2013 and 2002 was weighted by China sixth National Population Census （2010）. The relationship between undernutrition and gender/age groups/different areas use weighted logistic regression. Results The results indicated the overall prevalence of stunting, underweight, and wasting of Chinese children under S-year was 8.1%, 2.4%, and 1.9% in 2013, respectively. The prevalence of stunting was higher for children aged 12-47 month, while underweight was higher for children aged 48-59 month. The prevalence of undernutrition was higher in rural areas than in urban areas, especially in poor rural areas. There was a decline of stunting, underweight, and wasting between 2002 and 2013 among the children, with greater reduction in rural areas than in urban areas. Conclusion The prevalence of undernutrition of children under 5-year remains high in rural areas especially in poor rural areas in China. It is urgent to take action to control undernutrition in the vulnerable areas and subgroups.
基金provided by the Science&Technology Basic Resources Investigation Program of China [grant number:2017FY101101 and 2017FY101103]
文摘Objective The primary objective of this study was to examine the validity and reliability of a semi-quantitative food frequency questionnaire(FFQ) among Chinese children aged 12-17 years. Methods A semi-quantitative 72-food item FFQ was developed for children aged 12-17 years. The reliability and validity of this FFQ were evaluated against 24-h dietary recalls(24 h DRs) to measure the consumption of foods and nutrients. We administered two FFQs and three DRs to children(N = 160) over a period of 1 month to evaluate the reliability and validity. Reliability was examined by quartile agreement and intraclass correlation coefficients(ICCs), and validity was examined by quartile agreement, Bland-Altman plots and correlation with DRs. Results For reliability, the ICCs between the two FFQs ranged from 0.21 to 0.76 for foods and nutrients, and the quartile agreement ranged from 70.0% to 95.0% in the same or adjacent quartiles. Spearman’s correlation coefficients of foods and nutrients between the second FFQ and the 24 h DRs ranged from-0.04 to 0.59. The Bland-Altman plots demonstrated good agreement across the range of intakes among nutrients. The quartile agreement ranged from 50.0% to 100.0%, with infrequent misclassification. Conclusion The FFQ assessment of dietary intakes demonstrated acceptable relative validity and high reproducibility for Chinese children aged 12-17 years.
基金funded by National Scientific and Technological Basic Resources Investigation Program ‘Research and application of nutrition and health system for children aged 0-18 years in China’[2017FY101100]
文摘Objective This study is aimed to report the development,the reliability and validity of the Chinese Children Physical Activity Questionnaire(CCPAQ)which was designed for the assessment of physical activity pattern in young population in China.Methods The CCPAQ was administered for two times in 119 children(mean age 13.1±2.4 years;boys 47%)to examine reliability by using intraclass correlation coefficients.Validity was determined in 106 participants by agreement with the CCPAQ measures and the objective method,the ActiGraph accelerometer.Data on physical activity patter n including time spe nt on d iff ere nt intensi ties and total physical activity,sedentary behavior as well as physical activity energy expenditure were used to assess the validity with Spearman's correlation coefficient and the Bland-Altman plots.Results The reliability coefficient of the CCPAQ ranged from 0.63-0.93(Intra-class correlation coefficient).Spearman's correlation coefficient for validity of time spent on total physical activity and sedentary behavior were all 0.32(P<0.001),and for physical activity energy expenditure was 0.58(P<0.001).Time spent on moderate-to-vigorous physical activity and light physical activity showed a relatively low correlation with the accelerometer(rho=0.20,P=0.040;rho=0.19,P=0.054).Conclusion The CCPAQ appears to be a promising and feasible method to assess physical activity pattern in Chinese children.
基金supported by the National Special Program for Science&Technology Basic Resources Investigation of China[Grant No.2017FY101100,2017FY101101,2017FY101102,2017FY101103,2017FY101104,2017FY101105,2017FY101106,and 2017FY101107]。
文摘The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China(CNHSC)was to collect basic data on the nutrition,development,and health status for children in different regions across China using evidence-based,reliable,and cost-effective approaches.Children and their parents or guardians from seven regions(south,southwest,north,northwest,eastern,central,and northeast China)in China were recruited.A multi-stage stratified randomized sampling method was used.Two provinces were randomly sampled from each of the seven regions,from which one urban district and one rural country were also randomly sampled,resulting in a total of 28 survey counties/districts.Dietary surveys,health examinations,laboratory testing,and questionnaires were used to collect dietary intake,nutritional status,child development,and health status information.Nutrition,health,and lifestyle assessment of children and their parents was determined using the Knowledge Attitude Practice(KAP)survey.Greater than 100,000 children(38,000 children<6 years of age and 66,000 children6-17 years of age)completed the survey.The survey provided comprehensive data on child nutrition and health status for future studies and will serve as the basis for an integrated nutrition and health improvement strategies proposal for children in China.
基金supported by the National High Technology Research and Development Program of China(863 Program)(No.2010AA023004)
文摘Objective To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column （2.1×100 mm, 1.8 μm）. The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESl＋ionization and detected in multiple reaction monitoring （MRM） with three acquisition functions. Results Calibration curves ranged from 0.5-160 ng/mL （thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal）, and 2.5-800 ng/mL （pantothenic acid, FAD and nicotinamide） （R^2=0.990-0.999）. The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification （LOQ） for all vitamins was between 0.25 and 3 lag/L. Conclusion This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.
文摘INTRODUCTION Globally,childhood obesity has gradually become prevalent in recent decades.According to estimations by United Nations International Children's Emergency Fund(UNICEF),the World Health Organization(WHO),and the World Bank,the global prevalence of being overweight for children under 5 years rose from 4.9%in 2000 to 5.6%in 2019[1].The Institute for Health Metrics and Evaluation(IHME)estimated that,between 1980 and 2015,the worldwide proportion of obesity increased from 3.9%to 7.2%and 3.7%to 6.4%in boys and girls aged 2-4 years,respectively121.Meanwhile,the Non-Communicable Diseases Risk Factor Collaboration reported that the global prevalence of obesity rose from 0.9%to 7.8%and 0.7%to 5.6%in boys and girls aged 5-19 years,respectively,between 1975 and 2016[3].Globally,the total number of overweight and obese individuals reached 40 and 340 million in children under 5 years and aged 5-19 years,respectively,in 2016.
基金supported by the National Natural Science Foundation of China(Grant Nos.11372313,11002011 and 11202213)the Key Research Program of the Chinese Academy of Sciences(Grant No.KJZD-EW-M01)+1 种基金the Instrument Developing Project of the Chinese Academy of Sciences(Grant No.Y2010031)the Fundamental Research Funds for the Central Universities and the Beijing Higher Education Young Elite Teacher Project
文摘Dislocations are of great importance in revealing the underlying mechanisms of deformed solid crystals.With the development of computational facilities and technologies,the observations of dislocations at atomic level through numerical simulations are permitted.Molecular dynamics(MD)simulation suggests itself as a powerful tool for understanding and visualizing the creation of dislocations as well as the evolution of crystal defects.However,the numerical results from the large-scale MD simulations are not very illuminating by themselves and there exist various techniques for analyzing dislocations and the deformed crystal structures.Thus,it is a big challenge for the beginners in this community to choose a proper method to start their investigations.In this review,we summarized and discussed up to twelve existing structure characterization methods in MD simulations of deformed crystal solids.A comprehensive comparison was made between the advantages and disadvantages of these typical techniques.We also examined some of the recent advances in the dynamics of dislocations related to the hydraulic fracturing.It was found that the dislocation emission has a significant effect on the propagation and bifurcation of the crack tip in the hydraulic fracturing.
