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Expression Patterns of Nine Ammonium Transporters in Rice in Response to N Status

Pedosphere 2012年第6期22卷 860-869页

作者： li Su-Mei li bao-zhen SHI Wei-Ming State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesHunan 410125(China)

Nitrogen use efficiency （NUE） was very low in China and a loss of as much as 7070 of the applied nitrogen fertilizers was reported in high-yielding rice fields. In order to investigate the molecular basis of high-affinity ammonium transport or uptake into rice （Oryza sativa L.）, we analyzed the expression profiles of nine ammonium transporters （AMT）, three each of OsAMT1, OsAMT2 and OsAMT3, at two different N requirement stages （young seedling stage and tillering stage） of rice growth as well as the changes in these expression patterns according to external N status using real-time reverse transcription polymerase chain reaction （RT-PCR）. The results suggested that the nine OsAMT genes were expressed in different organs of rice plants, including mature roots, new roots, stems, old leaves and new leaves and that the expression patterns were organ specific and independent of the positions of the corresponding proteins in the phylogenetic tree. OsAMT1;1, 3;2 and 3;3 were expressed in the roots and shoots, primarily old leaves, OsAMT1;2 and 1;3 mainly in the roots, and OsAMT2;1, 2;2, 2;3 and 3;1 mainly in the shoots, primarily in new leaves, and relatively more in the stems than other genes. The expression patterns at the two different N requirement stages were the same; however, at the tillering stage with greater N requirements, the OsAMTs transcript levels were greater than those at the young seedling stage with low N requirements. N starvation for 48 h up-regulated OsAMT1;1, 1;2, 3;1, 3;2, 3;3 and down-regulated OsAMT1;3 mRNA abundance. Following N starvation, NH4＋ and NH4NO3 re-supply down-regulated OsAMT1;2 and 3;3 and up-regulated OsAMT1;3, whereas NO3 re-supply down-regulated OsAMT1;1 and 1;2. These suggested that the organ-specific expression pattern of OsAMT could be regulated by N requirement and external N status.

关键词： external N level gene expression growth stage N requirement plant organ

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Spatiotemporal variations of drought and driving factors based on multiple remote sensing drought indices:A case study in karst areas of southwest China

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Journal of Mountain Science 2023年第11期20卷 3215-3232页

作者： LU Xian-jian li zhen-bao YAN Hong-bo liANG Yue-ji College of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541004China

Droughts are recurrent in southwest China due to the fragility and sensitivity of the karst *** events have serious impacts on local agricultural output,ecological diversity,and social *** spatiotemporal variations and driving factors of drought in this area is of extreme importance for effective mitigation *** karst areas situated in southwest China were spatially divided into seven sub-regions according to the topography and degree of karst *** indices,including vegetation condition index(VCI),temperature condition index(TCI),vegetation health index(VHI),normalized vegetation water supply index(NVSWI),and temperature vegetation drought index(TVDI),were calculated from MODIS data during 2000 and 2018for each sub-region,and drought patterns were *** results show that droughts were found to be concentrated in sub-regions such as karst basin,karst plateau,karst gorge,and karst depression ***,there were more drought conditions in karst areas than in non-karst *** addition,improvements to drought situation in the study period are significant(plightly(<3.4%)in areas undergoing urban ***'s correlation coefficients between drought indices and temperature are generally above 0.5 in all ***,the correlation coefficients between drought indices and precipitation mostly fall within the range of 0.3-0.4,indicating a weaker *** explanation for the spatiotemporal patterns of drought is that karst phenomena are the natural basis of drought and agricultural production is one of important driving *** changes of drought conditions have benefited from efforts to control rocky desertification and restore ecosystems over the past years.

关键词： Drought Driving factors Karst phenomena Remote sensing

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Molecular Basis and Regulation of Ammonium Transporter in Rice

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Rice science 2009年第4期16卷 314-322页

作者： li bao-zhen Mike MERRICK li Su-mei li Hong-ying ZHU Shu-wen SHI Wei-ming Su Yan-hua State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Department of Molecular Microbiology John Innes Centre Colney Lane Norwich NR4 7UH UK

Rice grows in flooded paddy fields and takes up ammonium as the preferred nitrogen （N） source. Ammonium uptake is facilitated by a family of integral membrane proteins known as ammonium transporters found in all domains of life. However, the molecular mechanism and functional characteristics of the ammonium transporters （AMT） in rice have not been determined in detail yet. In this review, we report a genome-wide search for AMT genes in rice, resulting in the increase of the number of potential AMT proteins to at least 12, including members of both the alpha and beta sub-groups. Analysis of the predicted protein sequences for the 12 OsAMT proteins identified many conserved phosphorylation sites in both the alpha and beta group members, which could potentially play a role in controlling the activity of the transporters. Present knowledge of the expression of rice AMT genes is also summarized in detail. Future studies should focus on the structural and functional characteristics of OsAMT proteins to provide insight into the mechanism of ammonium uptake and its regulation in rice. Such research could improve utilization and decrease wastage of N fertilizer in rice cultivation.

关键词： rice ammonium transporter expression regulation phosphorylation site

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Fate of low-molecular-weight organic phosphorus compounds in the P-rich and P-poor paddy soils

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Journal of Integrative Agriculture 2021年第9期20卷 2526-2534页

作者： li bao-zhen Anna GUNINA Mostafa ZHRAN Davey L.JONES Paul W.HILL HU Ya-jun GE Ti-da WU Jin-shui Key Laboratory of Agro-ecological Processes in Subtropical Region/Changsha Research Station for Agricultural&Environmental Monitoring Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125P.R.China Department of Environmental Chemistry University of KasselNordbahnhofstrae 1a 37213WitzenhausenGermany Department of Soil Biology and Biochemistry Dokuchaev Soil Science InstituteMoscow 119017Russian Federation Soil and Water Research Department Nuclear Research CenterAtomic Energy AuthorityAbou-Zaabl 13759Egypt School of Natural Sciences Bangor UniversityBangorGwynedd LL572UWUK University of Chinese Academy of Sciences Beijing 100049P.R.China

Continuous application of organic fertilizers can cause accumulation of organic phosphorus(P)in soil,especially in the lowmolecular-weight organic phosphorus(LMWOP)*** organic P pool represents a potentially important source of P for both plants and *** understand the effect of long-term fertilization(30 years)(P-rich soil)***(P-poor soil)on the bioavailability and fate of LMWOP in subtropical paddy soils,we determined the sorption and mineralization of 14 C-labeled adenosine,adenosine monophosphate(AMP),adenosine diphosphate(ADP),and adenosine triphosphate(ATP)in each *** contents of carbon,nitrogen,and P in the P-rich soil were more than two times greater than those in the P-poor *** mineralization rates of the LMWOP compounds were faster in the P-rich soil compared to the P-poor soil,and followed the order AMP>ADP>*** sterilized soil,all forms of adenosine-P were strongly sorbed to the solid phase and reached saturation in a short time,with the adsorbance increasing with the number of phosphate *** concluded that the mineralization of LMWOP compounds was repressed slightly by sorption to the solid phase,but only in the short ***,LMWOP compounds serve as readily available sources of C for microorganisms,making P available for themselves as well as for the ***,P accumulation and the progressive saturation of the P sorption sites in highly fertile soils may increase the potential risk of P runoff.

关键词： rice paddy phosphatase phosphorus cycling microbial community

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地震模拟振动台三参量控制算法超调修正

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振动与冲击 2010年第10期29卷 211-215页

作者：李振宝唐贞云纪金豹北京工业大学工程抗震与结构诊治北京市重点实验室北京100124

针对地震模拟振动台三参量控制算法中存在超调量过大的问题,提出了离线时域修正算法:通过时域内微分方程求解得出超调量存在的原因,进而从直接消除暂态分量出发,以三角函数、傅里叶变换为工具,提出了任意输入下超调量的修正方法,仿真结... 详细信息

针对地震模拟振动台三参量控制算法中存在超调量过大的问题,提出了离线时域修正算法:通过时域内微分方程求解得出超调量存在的原因,进而从直接消除暂态分量出发,以三角函数、傅里叶变换为工具,提出了任意输入下超调量的修正方法,仿真结果表明该方法大大降低了超调量,减小了在线计算量。同时,通过三参量在地震模拟振动台控制系统中的应用仿真得出:修正后的三参量在降低超调的同时未产生任何不利影响,能很好的应用于地震模拟振动台系统控制。

关键词：三参量控制超调量时域离线修正地震模拟振动台

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Interactions of Heavy Metal Ions with Paddy Soils as Inferred from Wien Effect Measurements in Dilute Suspensions

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Pedosphere 2006年第6期16卷 718-725页

作者： JIANG Jun li Cheng-bao ZHAO An-zhen XU Ren-Kou WANG Yu-Jun S. P. FRIEDMAN Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Institute of Soil Water and Environmental Sciences Agricultural Research Organization Voleani Center Bet Dagan 50250 Israel

Interactions of three heavy metal ions, Cu^2＋, Cd^2＋, and Pb^2＋, and, for comparison, Na^＋ with electrodialytic clay fractions （less than 2μm in diameter） of four paddy soils as well as a yellow-brown soil as a control soil were evaluated based on measurements of the Wien effect in dilute suspensions with a clay concentration of 10 g kg^-1 in four nitrate solutions of 2 × 10^-4/z mol L^-1, where z is the cation valence, and a nitric acid solution of 3 × 10^-5 mol L^-1, Field strengths ranging from 15 to 230 kV cm^-1 were applied for measuring the electrical conductivities （ECs） of the suspensions. The mean free binding energies between the various cations and all of the soils determined from exchange equilibrium increased in the order： Na^＋〈 Cd^2＋〈 Cu^2＋〈 Pb^2＋. In general, the ECs of the suspensions in the sodium nitrate solution were smaller than those of the suspensions in the heavy metal solutions because of the lower electrophoretic mobility of sodium compared to the divalent cations. In terms of relative electrical conductivity-field strength relationships, relative electrical conductivity （REC） of suspensions containing various cations at field strengths larger than about 50 kV cm^-1 were in the descending order： Na^＋〉 Cu^2＋〉 Cd^2＋〉 Pb^2＋ for all tested soils. A characteristic parameter of the REC-field strength curves, AREC200, REC at a field strength of 200 kV cm^-1 minus that at the local minimum of the concave segment of the REC-field strength curves, characterized the strength of adsorption of the cations stripped off by the applied strong electrical field, and for all soils the values of AREC200 were generally in the order： Na^＋〈 Cu^2＋ ≤ Cd^2＋〈 Pb^2＋.

关键词： binding energy electrical conductivity field strength heavy metal ions paddy soils

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基于子结构试验的土-结相互作用实现研究

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工程力学 2017年第B6期34卷 214-219页

作者：郭珺唐贞云李易李振宝北京工业大学城市与工程安全减灾教育部重点实验室北京100124

传统的土-结相互作用试验由于加载系统的出力和尺寸限制,目前只能进行大比例缩尺试验,且对于大跨空间结构、桥梁等长大型结构考虑土-结相互作用的地震作用性能,目前的试验设备也存在局限。而实时动力子结构试验方法将试验对象不可建模... 详细信息

传统的土-结相互作用试验由于加载系统的出力和尺寸限制,目前只能进行大比例缩尺试验,且对于大跨空间结构、桥梁等长大型结构考虑土-结相互作用的地震作用性能,目前的试验设备也存在局限。而实时动力子结构试验方法将试验对象不可建模部分在实验室进行物理试验,剩余部分作为数值模型进行建模,二者保证同步可对整体试验对象性能进行模拟,克服了传统土-结相互作用试验研究的不足。该文应用动力子结构试验方法,对土-结相互作用问题进行了研究,建立了整体试验模型及混合动力子结构试验模型,并通过试验进行了验证。利用该文发展的子结构试验技术,分别对多跨连续刚构桥梁和钢筋混凝土高墩大跨度刚构桥梁考虑土-结相互作用抗震性能进行了试验研究,试验结果表明该方法存在一定应用价值。

关键词：土-结相互作用振动台子结构试验多点地震动输入应用

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多自由度实时子结构试验系统稳定性分析方法

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工程力学 2018年第3期35卷 22-29页

作者：唐贞云郭珺洪越李易李振宝北京工业大学城市与工程安全减灾教育部重点实验室北京100124

实时子结构试验将数值模拟和物理试验相结合,充分发挥各自优点,为工程结构研究提供了一种新的试验手段。系统稳定性是保证实时子结构试验成功实现的前提,但现有研究成果主要针对单自由度结构,多自由度系统稳定性评价方法所需参数相对复... 详细信息

实时子结构试验将数值模拟和物理试验相结合,充分发挥各自优点,为工程结构研究提供了一种新的试验手段。系统稳定性是保证实时子结构试验成功实现的前提,但现有研究成果主要针对单自由度结构,多自由度系统稳定性评价方法所需参数相对复杂、稳定性指标物理意义不够明确。该文结合振型叠加法和增益裕度概念发展了多自由度稳定性分析方法,通过试验验证了该方法的有效性。同时运用该方法就时滞补偿下实时子结构试验系统稳定性进行了评估,并阐述了时滞补偿对实时子结构试验系统稳定性的影响机理。研究结果表明该方法能准确评价多自由度子结构试验系统稳定性,时滞补偿对子结构稳定性可能产生有利也可能产生不利影响。

关键词：实时子结构试验振动台多自由度稳定性时滞补偿

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应用Python-GPU求解的实时混合试验方法研究

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振动工程学报 2023年第2期36卷 517-525页

作者：董晓辉唐贞云李振宝杜修力北京工业大学城市与工程安全减灾教育部重点试验室北京100124 河北省地震灾害防御与风险评价重点实验室河北三河065201

提出了基于Python和图形处理器(GPU)数值求解的实时混合试验系统。将土-结相互作用系统作为试验模型,使用Python-GPU代替CPU数值求解,对提出的实时混合试验系统进行了仿真与试验验证。研究结果表明,使用Python-GPU对无条件稳定算法求解... 详细信息

提出了基于Python和图形处理器(GPU)数值求解的实时混合试验系统。将土-结相互作用系统作为试验模型,使用Python-GPU代替CPU数值求解,对提出的实时混合试验系统进行了仿真与试验验证。研究结果表明,使用Python-GPU对无条件稳定算法求解,积分步长20 ms时GPU实时求解模型自由度超过24000,是同一台计算机CPU求解规模的7倍左右,提升了实时混合试验的试验能力。

关键词：实时混合试验图形处理器 Python 数值积分算法求解效率

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应用GPU求解的实时子结构试验架构与性能验证

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振动工程学报 2022年第1期35卷 64-71页

使用图形处理器(GPU)代替传统中央处理器(CPU)作为数值求解硬件,建立基于LABVIEW-MATLAB-GPU的实时子结构试验架构。以土-结相互作用系统为载体,通过数值仿真与试验对该架构的性能进行验证。试验与仿真结果表明,本文方法将实时子结构试... 详细信息

使用图形处理器(GPU)代替传统中央处理器(CPU)作为数值求解硬件,建立基于LABVIEW-MATLAB-GPU的实时子结构试验架构。以土-结相互作用系统为载体,通过数值仿真与试验对该架构的性能进行验证。试验与仿真结果表明,本文方法将实时子结构试验中数值子结构求解自由度提高到27000,提升了数值模型求解规模,拓展了实时子结构试验应用范围。

关键词：实时子结构试验图形处理器数值积分算法振动台有限元模拟

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