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Spatial variation of technical efficiency of cereal production in China at the farm level

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Journal of Integrative Agriculture 2021年第2期20卷 470-481页

作者： ZHOU Wen-bin WANG Huai-yu HU Xi duan feng-ying Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China School of Management and Economics Beijing Institute of TechnologyBeijing 100081P.R.China Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518108P.R.China

Rice, wheat and maize are the main staple food crops to ensure the food security in China with diversified climate condition, cropping system and environmental and socio-economic factors across provinces. Spatial variation of technical efficiency in farmers' field is helpful to understand the potential to improve farmers' yield given the inputs level and reduce the yield gap. The study is based on a large-scale farm household survey which covered 1 218 rice farmers, 3 566 wheat farmers and 2 111 maize farmers in the main producing areas. The results indicate that rice farmers are with very high technical efficiency level, nearly 0.9 on average, with little room to improve the efficiency of agricultural inputs. Similar results have been found in wheat and maize farmers' fields, although the technical efficiency levels are lower than that of rice farmers while still at a high level with obvious variation across regions. Farmers with higher yield level also achieve better technical efficiency in most locations. Both local environmental and socio-economic factors significantly affect farmers' technical efficiency. In the context of urbanization and economic development, improved and new agricultural technologies need to be prioritized and facilitated to improve cereal yield at farm level.

关键词： technical efficiency spatial variation rice wheat maize

Transcriptional Regulation of Expression of the Maize Aldehyde Dehydrogenase 7 Gene (ZmALDH7B6) in Response to Abiotic Stresses

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Journal of Integrative Agriculture 2014年第9期13卷 1900-1908页

作者： AN Xia duan feng-ying GUO Song CHEN Fan-jun YUAN Li-xing GU Ri-liang Department of Plant Nutrition Center for ResourcesEnvironment and Food SecurityChina Agricultural University

Aldehyde dehydrogenases（ALDHs） represent a large protein family, which includes several members that catalyze the oxidation of an aldehyde to its corresponding carboxylic acid in plants. Genes encoding members of the ALDH7 subfamily have been suggested to play important roles in various stress adaptations in plants. In this study, quantitative RT-PCR analysis revealed that a maize ALDH7 subfamily member（ZmALDH7B6） was constitutively expressed in various organs, including roots, leaves, immature ears, tassels, and developing seeds. The abundance of ZmALDH7B6 mRNA transcripts in maize roots was increased by ammonium, NaCl, and mannitol treatments. To further analyze tissue-specific and stress-induced expression patterns, the 1.5-kb 5′-flanking ZmALDH7B6 promoter region was fused to the β-glucuronidase（GUS） reporter gene and introduced into maize plants. In roots of independent transgenic lines, there was significant induction of GUS activity in response to ammonium supply, confirming ammonium-dependent expression of ZmALDH7B6 at the transcript level. Histochemical staining showed that GUS activity driven by the ZmALDH7B6 promoter was mainly localized in the vascular tissues of maize roots. These results suggested that ZmALDH7B6 is induced by multiple environmental stresses in maize roots, and may play a role in detoxifying aldehydes, particularly in vascular tissue.

关键词： abiotic stress aldehyde dehydrogenase gene expression promoter transgenic maize

Ammonium-dependent regulation of ammonium transporter ZmAMT1s expression conferred by glutamine levels in roots of maize

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Journal of Integrative Agriculture 2022年第8期21卷 2413-2421页

作者： HUI Jing LIU Zhi duan feng-ying ZHAO Yang LI Xue-lian AN Xia WU Xiang-yu YUAN Li-xing College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

In maize,two root epidermis-expressed ammonium transporters ZmAMT1;1a and ZmAMT1;3 play major roles in highaffinity ammonium ***,the transcriptional regulation of ZmAMT1s in roots for ensuring optimal ammonium acquisition remains largely ***,using a split root system we showed that ZmAMT1;1a and ZmAMT1;3transcript levels were induced by localized ammonium supply to nitrogen-deficient *** enhanced expression of Zm AMT1s correlated with increases in ^(15)NH_(4)^(+)influx rates and tissue glutamine concentrations in *** ammonium was supplied together with methionine sulfoximine,an inhibitor of glutamine synthase,ammonium-induced expression of ZmAMT1s disappeared,suggesting that glutamine rather than ammonium itself regulated ZmAMT1s *** glutamine was supplied to nitrogen-deficient roots,expression levels of ZmAMT1s were enhanced,and negative feedback regulation could subsequently occur by supply of glutamine at a high ***,our results indicated an ammonium-dependent regulation of ZmAMT1s at transcript levels,and a dual role of glutamine was suggested in the regulation of ammonium uptake in maize roots.

关键词： ammonium transporter pH glutamine maize roots nitrogen transcriptional regulation

Yield gap and resource utilization efficiency of three major food crops in the world——A review

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Journal of Integrative Agriculture 2021年第2期20卷 349-362页

作者： RONG Liang-bing GONG Kai-yuan duan feng-ying LI Shao-kun ZHAO Ming HE Jianqiang ZHOU Wen-bin YU Qiang College of Natural Resources and Environment Northwest A&F UniversityYangling 712100P.R.China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100P.R.China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory for Agricultural Soil and Water Engineering in Arid Area Ministry of EducationNorthwest A&F UniversityYangling 712100P.R.China Institute of Water-Saving Agriculture in Arid Areas of China Northwest A&F UniversityYangling 712100P.R.China School of Life Sciences University of Technology SydneyBroadwayNSW 2007Australia College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049P.R.China

Yield gap analysis could provide management suggestions to increase crop yields,while the understandings of resource utilization efficiency could help judge the rationality of the *** on more than 110 published papers and data from Food and Agriculture Organization (FAO,***/faostat) and the Global Yield Gap and Water Productivity Atlas (***),this study summarized the concept,quantitative method of yield gap,yield-limiting factors,and resource utilization efficiency of the three major food crops (wheat,maize and rice).Currently,global potential yields of wheat,maize and rice were 7.7,10.4 and 8.5 t ha^(–1),***,actual yields of wheat,maize and rice were just 4.1,5.5 and 4.0 t ha^(–1),***,nutrients,moisture,crop varieties,planting dates,and socioeconomic conditions are the most mentioned yield-limiting *** terms of resource utilization,nitrogen utilization,water utilization,and radiation utilization efficiencies are still not optimal,and this review has summarized the main improvement *** current research focuses on quantitative potential yield and yield gap,with a rough explanation of yield-limiting *** research should use remote sensing data to improve the accuracy of the regional scale and use machine learning to quantify the role of yield-limiting factors in yield gaps and the impact of change crop management on resource utilization efficiency,so as to propose reasonable and effective measures to close yield gaps.

关键词： food crops yield yield gap resource utilization efficiency yield-limiting factor

Simple and Mild Syntheses of Optically Active 2-(N,N-Dialkylamino)oxazolines

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Chemical Research in Chinese Universities 2010年第3期26卷 394-397页

作者： JIA Xu-dong duan Hai-feng LIN ying-jie CAO Jun-gang LIANG Da-peng LUO Xu-yang JIANG feng GAO Han WU Mao-cheng Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

Chloroamidinium salts and a-amino alcohols derived from commercially available tetraalkyl ureas and α-amino acids, respectively, can be used for the syntheses of optically active 2-（N,N-dialkylamino）oxazolines in moderate to excellent yields without any catalyst. It is a simple and mild method for the syntheses of optically active oxazolines

关键词： Amino alcohol Oxazoline Chloroamidinium salt Guanidine

Efficient One-pot Synthesis of 12-Aryl-8, 9, 10, 12- tetrahydrobenzo [a]anthen-11-ones Under Solvent-free Conditions

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Chemical Research in Chinese Universities 2013年第1期29卷 82-86页

作者： JIA Xu-dong HAN Song-yang duan Hai-feng LIN ying-jie CAO Jun-gang LIANG Da-peng WUMao-cheng Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

Multi-component condensation of 2-naphthol, aromatic aldehydes, and cyclic 1,3-dicarbonyl compounds catalyzed by ionic liquid [NSPTEA][HSO4] was accomplished for the synthesis of a series of 12-aryl-8,9,10,12- tetrahydrobenzo[a]xanthen-11-ones under solvent-free conditions. High yields, ease recovery, short reaction time and reusability of catalyst are significant advantages. ZrOC12＂8H20 was also found to act as an effective catalyst towards this transformation.

关键词： Aldehyde Ionic liquid ZrOCI28HzO Multi-component reaction Solvent-free condition

Highly Efficient and Recyclable Catalyst HBF_4·SiO_2 Catalyzed Synthesis of β-Enamino Compounds Under Solvent-free Conditions

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Chemical Research in Chinese Universities 2011年第5期27卷 792-794页

作者： GAO Han JIA Xu-dong duan Hai-feng LIN ying-jie GAO Jun-gang LIANG Da-peng WU Mao-cheng Department of Organic Chemistry College of Chemistry dilin University Changchun 130012 l~ R. China

Fluoroboric acid adsorbed on silica-gel（HBF4·SiO2） has been found to be an extremely efficient and recyclable catalyst for the preparation of β-enaminones and β-enamino esters under solvent-free conditions.

关键词： β-Enaminone β-Enamino ester HBF4·SiO2 Solvent-free condition

盐酸氨溴索预防放射性肺炎疗效及安全性的Meta分析

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中国全科医学 2015年第17期18卷 2057-2061页

作者：洪炳段凤英南昌大学第二附属医院呼吸内科江西省南昌市330006

目的系统评价盐酸氨溴索预防放射性肺炎的疗效及安全性。方法计算机检索Pub Med、EMBase、The Cochrane Library(2014年第9期)、维普中文科技期刊数据库(VIP)、中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方数据库,检索时间从建库... 详细信息

目的系统评价盐酸氨溴索预防放射性肺炎的疗效及安全性。方法计算机检索Pub Med、EMBase、The Cochrane Library(2014年第9期)、维普中文科技期刊数据库(VIP)、中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方数据库,检索时间从建库至2014年9月,收集试验组为盐酸氨溴索+放疗,对照组为放疗治疗癌症的随机对照试验(RCT)。对纳入文献进行质量评价和数据提取,采用Rev Man 5.1软件对放射性肺炎、放射性肺纤维化的发生率及放疗疗效进行分析。结果共纳入8篇RCT文献733例患者,其中试验组369例,对照组364例。仅3篇文献提及具体随机分配方法,盲法报道均不充分。Meta分析结果显示,试验组放射性肺炎发生率低于对照组,差异有统计学意义〔RR=0.46,95%CI(0.37,0.58),P<0.01〕;试验组放射性肺纤维化发生率低于对照组,差异有统计学意义〔RR=0.45,95%CI(0.37,0.54),P<0.01〕。两组放疗疗效比较,差异无统计学意义〔RR=1.03,95%CI(0.96,1.11),P=0.39〕。在剔除非肺癌、非常规放疗文献后,无论放射性肺炎和放射性肺纤维化发生率,固定及随机效应模型结果均相等或近似相等,且均与原结果无明显差异,说明Meta分析结果稳定。基于放射性肺炎发生率的发表偏倚分析结果显示,漏斗图对称性不佳,提示可能存在发表偏倚。结论盐酸氨溴索预防放射性肺炎安全、有效,且不影响放疗疗效,但受纳入文献质量不高及数量较少等原因影响,上述结论有待更多大样本、高质量RCT予以验证。

关键词：辐射性肺炎氨溴索随机对照试验 Meta分析

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肺炎衣原体感染促进冠心病发展的研究

国际呼吸杂志 2006年第10期26卷 774-775,780页

作者：卢俊段凤英南昌大学第二附属医院呼吸科 330006

高血压、糖尿病、高脂血症(或高脂饮食)、肥胖和吸烟一直被认为是冠心病(CHD)的传统危险因素,感染或免疫异常可能也是CHD发生发展的危险因素之一。肺炎衣原体(chlamydia pneumonia,Cpn)感染与CHD的发病相关性越来越引起学者们的关注,大... 详细信息

高血压、糖尿病、高脂血症(或高脂饮食)、肥胖和吸烟一直被认为是冠心病(CHD)的传统危险因素,感染或免疫异常可能也是CHD发生发展的危险因素之一。肺炎衣原体(chlamydia pneumonia,Cpn)感染与CHD的发病相关性越来越引起学者们的关注,大量的血清学、病理学以及动物模型等研究提示感染与CHD的发生发展等有关。近年许多研究表明Cpn感染后促进冠心病发展可能与使炎症因子增多从而影响动脉粥样斑块、通过热休克蛋白(HSP)途径损伤动脉的内皮细胞、影响脂质代谢、通过单核巨噬细胞途径损伤动脉的内皮细胞、增加血液凝固性、和破坏动脉粥样斑块纤维帽有关。

关键词：衣原体感染冠心病