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Farmer's Adoption of Improved Nitrogen Management Strategies in Maize Production in China: an Experimental Knowledge Training

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Journal of Integrative Agriculture 2013年第2期12卷 364-373页

作者： JIA Xiang-ping HUANG Ji-kun XIANG Cheng HOU Lin-ke ZHANG Fu-suo CHEN Xin-ping cui zhen-ling Holger Bergmann Center for Chinese Agricultural Policy Institute for Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Graduate University Chinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University Georg-August-Universitaet Goettingen

Chemical fertilizer plays an important role in increasing food production in China. Nevertheless, excessive nitrogen fertilizer use in China has resulted in severe environmental problems. The goal of this paper is to examine the impacts of an improved nitrogen management （INM） training experiment on farmers＇ chemical nitrogen （N） use behaviors in maize production in China. Based on household data collected from 813 maize farmers in Shandong, China, this study finds that while INM training can significantly reduce farmers＇ N fertilizer use, an INM training is not sufficient to change farmer＇s practices significantly, and farmers only partially adopted the recommended INM. This study reveals that China faces challenges to transform its agriculture to a low-carbon one. The research also sheds light on China＇s extension system and future technologies in meeting the objectives of reducing the excessive nitrogen fertilizer use in agricultural production.

关键词： maize nitrogen training farmer China

Validation of a Critical Nitrogen Curve for Summer Maize in the North China Plain

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Pedosphere 2014年第1期24卷 76-83页

作者： YUE Shan-Chao SUN Fu-Lai MENG Qing-Feng ZHAO Rong-Fang LI Fei CHEN Xin-Ping ZHANG Fu-Suo cui zhen-ling College of Resources and Environmental Sciences China Agricultural University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Agriculture Bureau of Binzhou College of Environmental Science and Engineering Zhongkai University of Agriculture and Engineering College of Ecology and Environmental Science Inner Mongolia Agricultural University

The concept of critical N concentration(N_c)has been widely used in agronomy as the basis for diagnosis of crop N status,and allows discrimination between field situations of sub-optimal and supra-optimal N supply.A critical N dilution curve of N_c=34.0W^(-0.37),where W is the aboveground biomass(Mg DM ha^(-1))and N_c the critical N concentration in aboveground dry matter(g kg^(-1)DM),was developed for spring maize in *** objectives were to validate whether this European critical N dilution curve was appropriate for summer maize production in the North China Plain(NCP)and to develop a critical N dilution curve especially for summer maize production in this *** total 231 data points from 16 experiments were used to test the European critical N dilution *** observations showed that the European critical N dilution curve was unsuitable for summer maize in the NCP,especially at the early growth *** the data obtained,a critical N dilution curve for summer maize in the NCP was described by the equation of N_c=27.2W^(-0,27),when aboveground biomass was between 0.64 and 11.17 Mg DM ha^(-1).Based on this curve,more than 90%of the data for the N deficiency supply treatments had an N nutrition index(NNI)1.

关键词： critical N dilution curve N nutrition index optimal N management plant-based N diagnostic indicator

In-Season Root-Zone Nitrogen Management Strategies for Improving Nitrogen Use Efficiency in High-Yielding Maize Production in China

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Pedosphere 2012年第3期22卷 294-303页

作者： MENG Qing-Feng CHEN Xin-Ping ZHANG Fu-Suo CAO Ming-Hui cui zhen-ling BAI Jin-Shun YUE Shan-Chao CHEN Su-Yi T.MULLER Center for Resources Environment and Food SecurityChina Agricultural UniversityBeijing 100193(China) Fertilization with Soil Chemistry(340i) Institute of Crop ScienceUniversity HohenheimStuttgart 70593(Germany)

Many recently developed N management strategies have been extremely successful in improving N use efficiency. How- ever, attempts to further increase grain yields have had limited success. Field experiments were conducted in 2007 and 2008 at four sites to evaluate the effect of an in-season root-zone N management strategy on maize （Zea mays L.）. According to the in-season root-zone N management, the optimal N rate （ONR） was determined by subtracting measured soil mineral N （NHa＋-N and NO3-N） in the root zone from N target values. Other treatments included a control without N fertilization, 70% of ONR~ 130% of ONR, and recommended N rate （RNR） by agronomists in China that have been shown to approach maize yield potentials. Although apparent N recovery for the ONR treatment was significantly higher than that under RNR in 2007, grain yield declined from 13.3 to 11.0 Mg ha-1 because of an underestimation of N uptake. In 2008, N target values were adjusted to match crop uptake, and N fertilization rates were reduced from 450 kg N ha-1 for RNR to 225 to 265 kg N ha 1 for ONR. High maize yields were maintained at 12.6 to 13.5 Mg ha 1 which were twice the yield from typical farmers＇ practice. As a result, apparent N recovery increased from 29% to 66%, and estimated N losses decreased significantly for the ONR treatment compared to the RNR treatment. In conclusion, the in-season root-zone N management approach was able to achieve high yields, high NUE and low N losses.

关键词： apparent N recovery environmental pollution N losses optimal N rate soil N supply

Multi-Residue Determination of Eight Anabolic Steroids by GC-MS in Muscle Tissues from Pigs

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Agricultural Sciences in China 2010年第2期9卷 306-312页

作者： ZENG Dong-ping, LIN cui-ping, ZENG zhen-ling, HUANG Xian-hui and HE Li-min Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, P.R. China Laboratory of Veterinary Pharmacology College of Veterinary Medicine South China Agricultural University Guangzhou 510640 China

A gas chromatography-mass spectrometry （GC-MS） method to determine eight anabolic steroids （diethylstilbestrol, methyltestosterone, norethindrone, 17α-ethynylestradiol, estradiol, 6α-methyl-17α-hydroxy-progesterone, estradiol benzoate, and chlormadinone acetate） was developed. Muscle samples were extracted with liquid-liquid extraction and clean-up was performed in two steps, the extracts obtained were derivatized with heptafluorbutyric （HBF） anhydride and analyzed by GC-MS. In the above method, the linear scope was 2.5-50 μg kg^-1. The range of the recoveries was 78.5-148% for diethylstilbestrol, 70.8-109% for methyltestosterone, 69.8-87.2% for norethindrone, 67.7-120% for 17α-ethynylestradiol, 82.8-103% for estradiol, 70.3-99.2% for 6α-methyl-17α-hydroxy-progesterone, 73.0-104% for estradiol benzoate, and 72.9- 91.8% for chlormadinone acetate. The range of the coefficients of variation within batches was 0.4-12%; the range of the coefficients of variation between batches was 6.4-11%. The limit of detections and the detection capability were 0.99 and 3.30 μg kg^-1 for diethylstilbestrol, 1.05 and 3.50 μg kg^-1 for methyltestosterone, 1.19 and 3.97 μg kg^-1 for norethindrone, 0.94 and 3.13 μg kg^-1 for 17α-ethynylestradiol, 1.45 and 4.83 μg kg^-1 for estradiol, 1.56 and 5.20 μg kg^-1 for 6α-methyl-17α- hydroxy-progesterone, 1.92 and 6.40 μg kg^-1 for estradiol benzoate, and 2.41 and 8.03 μg kg^-1 for chlormadinone acetate, respectively. These results showed that the method was widely available, accurate, and sensitive.

关键词： anabolic steroids GC-MS multi-residue determination pigs

液体培养基比色法快速检测结核分枝杆菌耐药性

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中国抗生素杂志 2006年第9期31卷 555-558页

作者：崔振玲王洁胡忠义同济大学附属上海市肺科医院上海市结核重点实验室

目的探讨液体培养基比色法在结核分枝杆菌(MTB)耐药性快速测定中的应用价值。方法将MTB分别接种于含药和不含药的液体培养基中,37℃培养6d,然后加入NaNO3试剂,37℃培养1d,进行硝酸盐还原检测试验。根据液体培养基颜色变化情况,判断药敏... 详细信息

目的探讨液体培养基比色法在结核分枝杆菌(MTB)耐药性快速测定中的应用价值。方法将MTB分别接种于含药和不含药的液体培养基中,37℃培养6d,然后加入NaNO3试剂,37℃培养1d,进行硝酸盐还原检测试验。根据液体培养基颜色变化情况,判断药敏结果。将检测结果与Bactec-960测定结果比较,分析硝酸盐还原酶比色法检测MTB耐药性的敏感性、特异性和准确性。结果以Bactec-960检测结果为判断标准,液体培养基比色法检测链霉素、异烟肼、利福平和乙胺丁醇耐药性结果与Bactec-960的符合率分别为100.0%、96.9%、98.1%和97.5%。结论液体培养基比色法检测MTB耐药性具有很高的敏感性和特异性,且需时较短、操作简便、结果准确、不需特殊仪器设备,可作为MTB耐药性的快速筛选方法。

关键词：结核分枝杆菌药敏试验硝酸盐还原酶 Bactec-960

不同控释氮肥对夏玉米同化物积累及氮平衡的影响

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应用生态学报 2014年第6期25卷 1745-1751页

作者：司东霞崔振岭陈新平吕福堂中国农业大学资源与环境学院北京100193 聊城大学农学院山东聊城252000

选用聚酯包膜尿素（Ncau、CRU）、磷矿粉包膜尿素（NhnP）和腐殖酸包膜尿素（NhnF）4种控释氮肥，研究了在区域推荐用量下一次性施用对夏玉米同化物累积分配及环境效应的影响．结果表明：控释氮肥CRU和Ncau的氮素释放曲线与夏玉米的氮... 详细信息

选用聚酯包膜尿素（Ncau、CRU）、磷矿粉包膜尿素（NhnP）和腐殖酸包膜尿素（NhnF）4种控释氮肥，研究了在区域推荐用量下一次性施用对夏玉米同化物累积分配及环境效应的影响．结果表明：控释氮肥CRU和Ncau的氮素释放曲线与夏玉米的氮素吸收吻合较好；与区域氮素推荐施肥技术相比，施用CRU的夏玉米产量可提高4．2％，施用Ncau可维持相近的产量水平；CRU显著增加了夏玉米花后干物质的累积量，Ncau则明显提高了花前干物质的累积比例；在降雨量较大的情况下，CRU可使氮素表观损失减少19kgN·hm^-2．一次性施用NhnF和NhnP可造成0．1％-8．9％的产量损失，氮素表观损失增加．CRU和Ncau两种控释氮肥均可在“总量控制、分期调控”的区域氮肥推荐用量下，作为区域氮肥推荐施肥的轻简化替代技术应用于夏玉米生产．

关键词：控释肥料夏玉米氮素释放养分吸收

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural Regeneration Research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam M.R.Groh Moein Yaqubi Qiao-ling cui Jo Anne Stratton G.R.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

花后氮肥调控对春玉米叶片光合性能及产量的影响

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玉米科学 2023年第4期31卷 131-139页

作者：陈日远马倩杨艳刘鹏阚凤玲崔振岭北京嘉博文生物科技有限公司北京100080 中国农业大学北京100020

为研究花后追施氮肥对春玉米产量、根系及叶片光合性能的影响,本试验根据春玉米全生育期氮肥调控方案(INM)的最优施氮量(ONR)基础上,在春玉米吐丝期(R1)、乳熟期(R2)设置3个追氮处理,R1、R2期不追施氮肥(N1处理);R1、R2期按照ONR方案追... 详细信息

为研究花后追施氮肥对春玉米产量、根系及叶片光合性能的影响,本试验根据春玉米全生育期氮肥调控方案(INM)的最优施氮量(ONR)基础上,在春玉米吐丝期(R1)、乳熟期(R2)设置3个追氮处理,R1、R2期不追施氮肥(N1处理);R1、R2期按照ONR方案追施氮肥(N2处理);R1、R2期在ONR方案基础上氮肥施用量增加50%(N3处理)。通过2年田间试验结果表明,与花后不再追施氮肥相比(N1),花后追施氮肥(N2、N3)能显著增加玉米功能叶的SPAD值和R2期叶面积指数(LAI),在每次追氮10 d后可提高穗位叶净光合速率(P_(n)),从而维持春玉米长灌浆时间和高灌浆速率,产量平均增加13.2%、22.0%。春玉米吐丝后28 d,取0~60 cm土层玉米根系分层分析后表明,花后追氮对春玉米总体根系形态和总根重无显著影响,但显著增加了10~20 cm和50~60 cm土层的根长和根表面积,对玉米后期延衰、维持叶片功能和养分、水分吸收有促进作用。在R1、R2期分别增施50%施氮量(N3),较N2(ONR)处理的春玉米叶片光合性能、根系形态及产量均有提高趋势。

关键词：春玉米花后追氮产量光合速率(Pn) 根系形态

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结核分枝杆菌脂蛋白研究进展

结核病与肺部健康杂志 2017年第2期6卷 110-113页

作者：崔振玲范琳同济大学附属上海市肺科医院上海市结核病(肺)重点实验室/上海市肺科医院结核病临床研究中心 200433

结核分枝杆菌脂蛋白是一类N端发生脂酰化修饰的蛋白,属于膜蛋白,少数可以分泌到培养上清中.目前对结核分枝杆菌脂蛋白的功能了解尚少,脂蛋白主要分布于结核分枝杆菌细胞壁中,已知部分脂蛋白参与细胞壁成分及营养物质的转运.脂蛋白在结... 详细信息

结核分枝杆菌脂蛋白是一类N端发生脂酰化修饰的蛋白,属于膜蛋白,少数可以分泌到培养上清中.目前对结核分枝杆菌脂蛋白的功能了解尚少,脂蛋白主要分布于结核分枝杆菌细胞壁中,已知部分脂蛋白参与细胞壁成分及营养物质的转运.脂蛋白在结核分枝杆菌与宿主的相互作用中发挥双重作用,一些脂蛋白作为结核分枝杆菌的毒力因子敲除后菌株毒力下降;还有一些脂蛋白可以作为免疫抗原提高宿主的免疫反应,被用于疫苗研究.更多结核分枝杆菌脂蛋白功能尚不清楚,需要进一步的研究阐明.

关键词：分枝杆菌,结核脂蛋白类毒力因子类免疫调节疫苗综述文献(主题)