检索结果-南通市图书馆

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

在线全文

学校读者我要写书评

暂无评论

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

基于省级“4+7”模块化医院感染管理专职人员培训平台的建立与实施

在线全文

学校读者我要写书评

暂无评论

医学信息 2024年第10期37卷 72-75页

作者：李倩李宝珍李红霞平宝华王晓艳章琦西安交通大学第一附属医院感染控制办公室西安交通大学公共政策与管理学院

在医院感染管理工作中，院感专职人员的能力对整个医疗机构的感染防控水平有重要的作用，为了确保全省新入职的感染管理专职人员达到科学、系统、连续、全面的培训，S省在省级层面搭建培训平台，创新建立“4+7”模块化培训体系，短期内... 详细信息

在医院感染管理工作中，院感专职人员的能力对整个医疗机构的感染防控水平有重要的作用，为了确保全省新入职的感染管理专职人员达到科学、系统、连续、全面的培训，S省在省级层面搭建培训平台，创新建立“4+7”模块化培训体系，短期内对全省院感新人进行同质化、规范化管理，探索出在省级建立统一平台培训的创新模式。

关键词：医院感染模块化专职人员培训

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

2018~2021年章丘区流行性腮腺炎的流行病学特征分析

在线全文

学校读者我要写书评

暂无评论

中国实用医药 2024年第13期19卷 162-165页

作者：郑金萍李宝珍张福新章丘区疾病预防控制中心 250200

目的了解2018~2021年章丘区流行性腮腺炎流行病学特征,比较2018~2021年流行性腮腺炎发情况,为有效防控流行性腮腺炎提供依据。方法对章丘区2018~2021年流行性腮腺炎及疫情监测资料进行描述性分析。结果 2018~2021年济南市章丘区通过... 详细信息

目的了解2018~2021年章丘区流行性腮腺炎流行病学特征,比较2018~2021年流行性腮腺炎发情况,为有效防控流行性腮腺炎提供依据。方法对章丘区2018~2021年流行性腮腺炎及疫情监测资料进行描述性分析。结果 2018~2021年济南市章丘区通过国家疫情网络系统直报流行性腮腺炎510例,年平均发病率为11.83/10万,发病率呈现上升的趋势。2018年流行性腮腺炎年平均发病率低于2019年、2020年、2021年,但差异无统计学意义(χ^(2)=0.649、0.360、1.621, P=0.420、0.549、0.203>0.05);2020年流行性腮腺炎年平均发病率低于2021年,但差异无统计学意义(χ^(2)=0.460, P=0.498>0.05)。2018~2021年中各月均有发病,发病集中在5~7月、9~11月,共324例,占63.53%。2018~2021年章丘区18个街道(镇)均有发病,城区(明水、双山)年均发病率为19.72/10万(245/1242272),农村(剩余街道或镇)为8.64/10万(265/3068589),比较差异有统计学意义(χ^(2)=91.873, P=0.00015岁发病48例,占总病例数的9.41%。510例患者中,学生158例,占30.98%;托幼机构儿童242例,占47.45%;散居儿童81例,占15.88%;农民19例,占3.73%;其他10例,占1.96%;以学生和托幼机构儿童为主,占总病例数78.43%。510例患者中,有明确麻疹腮腺炎风疹(麻腮风)疫苗免疫史159例,占总病例数的31.18%,其中6~15岁学生98例,占19.22%(98/510),占学生发病例数的62.03%(98/158);无免疫史或免疫史不详351例,占总病例数的68.82%,主要为流动儿童和成人。510例患者中28例有合并症,占5.49%。其中,合并颌下腺肿大20例,占总病例数的3.92%;合并脑炎4例,占总病例数的0.78%,均为学生;合并睾丸炎4例,占总病例数0.78%,均为>15岁青春期少年或成人。结论病例以学龄期儿童和托幼机构儿童为主,学校和托幼机构是预防控制腮腺炎的重点,严格入托入学查验接种证工作,消除免疫空白,提高腮腺炎疫苗两剂次接种率,同时加强对学校和托幼机构的督导力度,大力开展健康教育,是降低腮腺炎发病的主要措施。

关键词：流行性腮腺炎流行病学特征预防控制

在线全文

学校读者我要写书评

暂无评论

蒸汽管道气液两相流冲蚀研究

化工机械 2024年第3期51卷 484-487页

作者：李广印梁钧张国强赵晓隆李珍宝甘肃省特种设备检验检测研究院中国石油兰州石化分公司兰州理工大学石油化工学院

针对电厂加热器水位控制系统信号管存在的气液两相流对管道的冲蚀现象,采用壁厚测定、有限元仿真、冲蚀形貌SEM分析、腐蚀产物EDS、XRD等分析测试方法进行研究,以期为后续科研和工业生产提供借鉴。

关键词：管道冲蚀气液两相流气泡溃灭减薄腐蚀

在线全文

学校读者我要写书评

暂无评论

地震模拟振动台三参量控制算法超调修正

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

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

在线全文

学校读者我要写书评

暂无评论

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

Molecular Basis and Regulation of Ammonium Transporter in Rice

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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