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The Possible Effect of Climate Warming on Northern Limits of Cropping System and Crop Yield in China

Agricultural Sciences in China 2011年第4期10卷 585-594页

作者： yang xiao-guang LIU Zhi-juan CHEN Fu College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R. China College of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R.China

Significantly increasing temperature since the 1980s in China has become a consensus under the background of global climate change and how climate change affects agriculture or even cropping systems has attracted more and more attention from Chinese government and scientists. In this study, the possible effects of climate warming on the national northern limits of cropping systems, the northern limits of winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation in China from 1981 to 2007 were analyzed. Also, the possible change of crop yield caused by planting limits displacement during the periods 1950s-1981 and 1981-2007 was compared and discussed. The recognized calculation methods of agricultural climatic indices were employed. According to the indices of climatic regionalization for cropping systems, the national northern limits of cropping systems, winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation during two periods, including the 1950s-1980 and 1981-2007, were drawn with ArcGIS software. Compared with the situation during the 1950s- 1980, the northern limits of double cropping system during 1981-2007 showed significant spatial displacement in Shaanxi, Shanxi, Hebei, and Liaoning provinces and Beijing municipality, China. The northern limits of triple cropping system showed the maximum spatial displacement in Hunan, Hubei, Anhui, Jiangsu, and Zhejiang provinces, China. Without considering variety change and social economic factors, the per unit area grain yield of main planting patterns would increase about 54-106% if single cropping system was replaced by double cropping system, which turned out to be 27- 58% if double cropping system was replaced by triple cropping system. In Liaoning, Hebei, Shanxi, Shaanxi, Gansu, and Qinghai provinces, Inner Mongolia and Ningxia autonomous regions, China, the northern limits of winter wheat during 1981-200

关键词： climate warming the northern limits of cropping system the planting northern limits of winter wheat the planting northern limits of double rice crop yield

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Geographic Variation of Rice Yield Response to Past Climate Change in China

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Journal of Integrative Agriculture 2014年第7期13卷 1586-1598页

作者： yang Jie XIONG Wei yang xiao-guang CAO yang FENG Ling-zhi College of Resources and Environmental Sciences China Agricultural University Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences International Institute for Applied Systems Analysis (IIASA) Ecosystems Services and Management Program Laxenburg 2361 Austria Department of Agricultural and Biological Engineering University of Florida Gainesville FL 32600-0570 USA

Previous studies demonstrated climate change had reduced rice yield in China, but the magnitude of the reduction and the spatial variations of the impact have remained in controversy to date. Based on a gridded daily weather dataset, we found there were obvious changes in temperatures, diurnal temperature range, and radiation during the rice-growing season from 1961 to 2010 in China. These changes resulted in a signiifcant decline of simulated national rice yield （simulated with CERES-Rice）, with a magnitude of 11.5%. However, changes in growing-season radiation and diurnal temperature range, not growing-season temperatures, contributed most to the simulated yield reduction, which conifrmed previous estimates by empirical studies. Yield responses to changes of the climatic variables varied across different rice production areas. In rice production areas with the mean growing-season temperature at 12-14＆#176;C and above 20＆#176;C, a 1＆#176;C growing-season warming decreased rice yield by roughly 4%. This decrease was partly attributed to increased heat stresses and shorter growth period under the warmer climate. In some rice areas of the southern China and the yangtze River Basin where the rice growing-season temperature was greater than 20＆#176;C, decrease in the growing-season radiation partly interpreted the widespread yield decline of the simulation, suggesting the signiifcant negative contribution of recent global dimming on rice production in China＇s main rice areas. Whereas in the northern rice production areas with relatively low growing-season temperature, decrease of the diurnal temperature range was identiifed as the main climatic contributor for the decline of simulated rice yield, with larger decreasing magnitude under cooler areas.

关键词： climate change yield responses rice China

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Protein Requirements in Healthy Adults: A Meta-analysis of Nitrogen Balance Studies

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Biomedical and Environmental Sciences 2014年第8期27卷 606-613页

作者： LI Min SUN Feng PIAO Jian Hua yang xiao guang Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention School of public health Peking university

Objective The goal of this study was to analyze protein requirements in healthy adults through a meta-analysis of nitrogen balance studies. Methods A comprehensive search for nitrogen balance studies of healthy adults published up to October 2012 was performed, each study were reviewed, and data were abstracted. The studies were first evaluated for heterogeneity. The average protein requirements were analyzed by using the individual data of each included studies. Study site climate, age, sex, and dietary protein source were compared. Results Data for 348 subjects were gathered from 28 nitrogen balance studies. The natural logarithm of requirement for 348 individuals had a normal distribution with a mean of 4.66. The estimated average requirement was the exponentiation of the mean of the log requirement, 105.64 mg N/kg·d. No significant differences between adult age, source of dietary protein were observed. But there was significant difference between sex and the climate of the study site （P〈0.05）. Conclusion The estimated average requirement and recommended nutrient intake of the healthy adult population was 105.64 mg N/kg·d （0.66 g high quality protein/kg·d） and 132.05 mg N/kg·d （0.83 g high quality protein/kg·d）, respectively.

关键词： Protein requirement Nitrogen balance Estimated average requirement Recommendednutrient intake

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Current status and trends of wheat genetic transformation studies in China

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Journal of Integrative Agriculture 2015年第3期14卷 438-452页

作者： HE Yi WANG Qiong ZENG Jian SUN Tao yang guang-xiao HE guang-yuan The Genetic Engineering International Cooperation Base Ministry of Science and Technology/Key Laboratory of Molecular Biophysics Ministry of Education/College of Life Science and Technology Huazhong University of Science & Technology

More than 20 years have passed since the first report on successful genetic transformation of wheat. With the establishment and improvement of transformation platform, great progresses have been made on wheat genetic transformation both on its fundamental and applied studies in China, especially driven by the National Major Project for Transgenic Organism Breeding, China, initiated in 2008. In this review, wheat genetic transformation platform improvement and transgenic research progresses including new techniques applied and functional studies of wheat quality, yield and stress tolerant related genes and biosafety assessment are summarized. The existing problems and the trends in wheat transformation with traditional methods combined with genomic studies and genome editing technology are also discussed.

关键词： genetic modification quality stress tolerance transformation platform wheat

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Unified modeling of high temperature deformations of a Ni-based polycrystalline wrought superalloy under tension-compression, cyclic, creep and creep-fatigue loadings

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Science China(Technological Sciences) 2015年第2期58卷 248-257页

作者： HUANG Jia SHI Duo Qi yang xiao guang YU Hui Chen DONG Cheng Li School of Energy and Power Engineering Beihang University Beijing Institute of Aeronautical Materials

The complex deformation behaviors under tension-compression, cyclic, creep and creep-fatigue loadings of a nickel-base polycrystalline wrought superalloy at 650℃ and 700℃ were experimentally investigated. To uniformly simulate the complex deformation behaviors, the modified viscoplastic constitutive model combined with both the Kachanov damage evolution equation and the Ohno-Wang modification was formulated on the basis of the Chaboche theory. The simulated results on ten-sion-compression behavior, cyclic viscoplastic and creep deformations showed comprehensive predicting ability. With the obtained material parameters, the deformations in creep-fatigue interaction under three dwell types were simulated and the capability of the modified model was further verified with good accuracy.

关键词： superalloy constitutive relation fatigue creep creep-fatigue interaction

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Variation Characteristics of Hydrothermal Resources Effectiveness Under the Background of Climate Change in Southern Rice Production Area of China

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Journal of Integrative Agriculture 2013年第12期12卷 2260-2279页

作者： YE Qing yang xiao-guang DAI Shu-wei LI Yong GUO Jian-ping College of Resources and Environmental Science China Agricultural University Forestry Institute Jiangxi Agricultural University School of Natural Resources University of Nebraska-Lincoln Guizhou Key Laboratory of Mountainous Climate and Resources Chinese Academy of Meteorological Sciences

The spatiotemporal characteristics of hydrothermal resources in southern rice production area of China have changed under the background of climate change,and this change would affect the effectiveness of hydrothermal resources during local rice growing *** to the cropping system subdivision in southern rice production area of China during 1980s,this study used climate data from 254 meteorological stations and phonological data from 168 agricultural observation stations in the south of China,and adopted 6 international evaluation indices about the effectiveness of hydrothermal resources to analyze the temporal and spatial characteristics of hydrothermal resources during the growing period of single cropping rice system and double cropping rice system for 16 planting zones in the whole study *** results showed that：in southern rice production area of China,the effectiveness of thermal resources of single cropping rice area（SCRA） was less than that of double cropping rice area（DCRA）,whereas the effectiveness of thermal resources of both SARA and DCRA showed a decreasing *** index value of effective precipitation satisfaction of SCRA was higher than that of DCRA,nevertheless the index value of effective precipitation satisfaction of both SCRA and DCRA showed a decreasing *** was a significant linear relationship between effective thermal resource and water demand,likely water demand increased by 18 mm with every 100°C d increase of effective *** precipitation satisfaction index（EPSI） showed a negative correlation with effective heat,yet showed a positive correlation with effective *** reduced by 1% when effective heat resource increased by 125°C *** study could provide insights for policy makers,land managers or farmers to improve water and heat resource uses and rationally arrange rice production activities under global climate change condition.

关键词： climate change rice production area effectiveness of hydrothermal resources spatiotemporal characteristics

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Evaluation of Erythrocyte Iron Incorporation in Beijing Prepubertal Children Using a Single Stable Isotope Tracer Method

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Biomedical and Environmental Sciences 2020年第6期33卷 414-420页

作者： ZHANG Yu LI Ya Jie REN Tong Xiang LIU xiao Bing yang Li Chen PAO Jian Hua WANG Jurr yang xiao guang Key Laboratory of Trace Element Nutrition MOHChinese Center for Disease Control and PreventionBeijing 100050China Department of Preventive Medicine Changzhi Medical CollegeChangzhi 046000ShanxiChina National Institute of Metrology Beijing 100029China

Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal *** Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57 Fe twice daily to obtain a total of 30 mg 57 Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14 th day, 28 th day, 60 th day, and 90 th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron *** The percentage of erythrocyte 57 Fe incorporation increased starting 14 th day, reached a peak at 60 d(boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57 Fe obtained for girls in 60 th day was significantly higher than those obtained for boys(P < 0.0001).Conclusions The oral administration of 57 Fe to children can be used to obtain erythrocyte iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children.

关键词： Stable isotope tracer technique Iron Erythrocyte incorporation rate Beijing prepubertal children MC-ICP-MS

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Using an Alternative Method to Estimate the Status of Iodine Nutrition in Pregnant Women

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Biomedical and Environmental Sciences 2018年第7期31卷 535-538页

作者： LIU xiao Bing WU Meng ZHANG Yu WANG Lei PIAO Jian Hua yang Li Chen yang xiao guang Key Laboratory of Trace Element Nutrition of National Health and Family Planning Commission National Institute of Nutrition and Health of Chinese Center for Disease Control and Prevention Beijing 100050 China Maternal & Child Health Care Hospital of Shaanxi Province Xian 710000 Shaanxi China Chao yang District Center for Disease Control and Prevention Beijing 100021 China

Iodine is an element that is essential for the synthesis of thyroid *** intake of dietary iodine has been recognized as a critical factor for maintaining *** is a well-known fact that iodine deficiency can impede the production of thyroid hormones in both the mother and fetus,which increases the risk of brain damage in the fetal stage.

关键词： Cr UIC Using an Alternative Method to Estimate the Status of Iodine Nutrition in Pregnant Women UIE

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Application of UPLC-MS/MS Method for Analyzing B-vitamins in Human Milk

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Biomedical and Environmental Sciences 2015年第10期28卷 738-750页

作者： REN Xiang Nan YIN Shi An yang Zhen Yu yang xiao guang SHAO Bing REN Yi Ping ZHANG Jing National Institute for Nutrition and Health Chinese Center for Disease Control and Prevention Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning Beijing Research Center for Preventive Medicine Zhejiang Provincial Centre for Disease Prevention and Control

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.

关键词： B-vitamins Human milk UPLC-MS/MS

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Estimation of Iron Physiological Requirement in Chinese Children using Single Stable Isotope Tracer Technique

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Biomedical and Environmental Sciences 2022年第8期35卷 681-687页

作者： ZHANG Yu LIU xiao Bing REN Tong Xiang CAI Jie LU Jia Xi NIU Ran PIAO Jian Hua yang Li Chen WANG Jun yang xiao guang Chinese Center for Disease Control and Prevention Beijing 102206China Gansu Center for Disease Control and Prevention Gansu 73000LanzhouChina Key Laboratory of Trace Element Nutrition MOHNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China National Institute of Metrology Bejing 100029China Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBejing 100730China

Objective This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope *** Thirty boys(10.6±0.2 years)and 27 girls(10.4±0.2 years)were received oral 6 mg ^(57)Fe each day for 5 consecutive *** blood samples were subsequently drawn to examine the change of total iron concentration and ^(57)Fe abundance at day 0,14,28,60,90,180,360,450,540,630,*** iron physiological requirement was calculated by iron loss combined with iron circulation rate once ^(57)Fe abundance stabilized in human *** The iron physiological requirement was significantly lower in boys than those values in girls(16.88±7.12 vs.18.40±8.81μg/kg per day,P<0.05).Correspondingly,the values were calculated as 722.46±8.43μg/day for boys and 708.40±7.55μg/day for girls,*** nearly 10%iron absorption rate,the estimated average iron physiological requirement was 6.0 mg/day in boys and 6.2 mg/day in *** This study indicate that iron physiological requirement could require more daily iron intake in girls as compare with the values in boys having the same body *** findings would be facilitate to the new revised dietary reference intakes.

关键词： Iron absorption rate Physiological requirement Chinese children Stale isotope tracer Dietary reference intakes

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