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Abundance and Community Composition of Ammonia-Oxidizers in Paddy Soil at Different Nitrogen Fertilizer Rates

Journal of Integrative Agriculture 2014年第4期13卷 870-880页

作者： song ya-na LIN Zhi-min Institute of Biological Technology Fujian Academy of Agricultural Sciences

Ammonia oxidation, the first and rate-limiting step of nitrification, is carried out by both ammonia-oxidizing bacteria （AOB） and ammonia-oxidizing archaea （AOA）. However, the relative importance of AOB and AOA to nitrification in terrestrial ecosystems is not well understood. The aim of this study was to investigate the effect of the nitrogen input amount on abundance and community composition of AOB and AOA in red paddy soil. Soil samples of 10-20 cm （root layer soil） and 0-5 cm （surface soil） depths were taken from a red paddy. Rice in the paddy was fertilized with different rates of N as urea of N1 （75 kg N ha＂ yr-1）, N2 （150 kg N ha~ yrl）, N3 （225 kg N ha1 yrl） and CK （without fertilizers） in 2009, 2010 and 2011. Abundance and community composition of ammonia oxidizers was analyzed by real-time PCR and denaturing gradient gel electrophoresis （DGGE） based on amoA （the unit A of ammonia monooxygenase） gene. Archaeal amoA copies in N3 and N2 were significantly （P〈0.05） higher than those in CK and N1 in root layer soil or in surface soil under tillering and heading stages of rice, while the enhancement in bacterial amoA gene copies with increasing of N fertilizer rates only took on in root layer soil. N availability and soil NO3--N content increased but soil NH4＋-N content didn＇t change with increasing of N fertilizer rates. Otherwise, the copy numbers of archaeal amoA gene were higher （P〈0.05） than those of bacterial amoA gene in root lary soil or in surface soil. Redundancy discriminate analysis based on DGGE bands showed that there were no obvious differs in composition of AOA or AOB communities in the field among different N fertilizer rates. Results of this study suggested that the abundance of ammonia-oxidizers had active response to N fertilizer rates and the response of AOA was more obvious than that of AOB. Similarity in the community composition of AOA or AOB among different N fertilizer rates indicate that the community composition of ammonia-oxidizers w

关键词： ammonia-oxidizing bacteria ammonia-oxidizing archaea nitrogen fertilizer rates paddy soil

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Diversity of Microbial Community in a Paddy Soil with cry1Ac/cpti Transgenic Rice

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Pedosphere 2014年第3期24卷 349-358页

作者： song ya-na SU Jun CHEN Rui LIN yan WANG Feng Institute of Biological Technology Fujian Academy of Agricultural Sciences

Two types of crylAc/cpti transgenic rice （GM1 and GM2） and their parental non-crylAc/cpti rice （CK1 and CK2） were planted in the field at Wufeng, Fhjian Province, China for four years to investigate the influence of genetically modified rice on diversity of bacterial and fungal community in the paddy soil. The community composition and abundance of bacteria or fungi in the paddy soil were assessed at different growth stages of rice by denaturing gradient gel electrophoresis and real-time polymerase chain reaction based on 16S rRna gene or SSU rRna gene in the 4th year after the experimental establishment. The composition of bacterial or fungal community changed during rice growth, while no significant differences were observed between the fields cultivated with GM1 and CK1, or between the fields cultivated with GM2 and CK2 in either bacterial or fungal community composition. The copy numbers of bacterial 16S rRna gene in the soils with CK1, CK2, GM1 and GM2 ranged from 5.64 x 10i1 to 6.89 x 10li copies g-1 dry soil at rice growth stages, and those of fungal SSU rRna gene from 5.24 x 10s to 8.68 x l0s copies g-1 dry soil. There were no marked differences in the copies of bacterial 16S rRna gene or fungal SSU rRna gene between CK1 and GM1 or between CK2 and GM2 at any growth stage of rice. Planting crylAc/cpti transgenic rice had no significant effect on composition and abundance of bacterial and fungal community in paddy soil during the rice growing season at least in the short term.

关键词： bacterial community denaturing gradient gel electrophoresis fungal community genetically modified plants real-time polymerase chain reaction

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Changes in bacterial community and abundance of functional genes in paddy soil with cry1Ab transgenic rice

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Journal of Integrative Agriculture 2021年第6期20卷 1674-1686页

作者： song ya-na CHEN Zai-jie WU Ming-ji LI Gang WANG Feng Institute of Biotechnology Fujian Academy of Agricultural Sciences/Fujian Provincial Key Laboratory of Genetic Engineering for AgricultureFuzhou 350003P.R.China

A field experiment involving cry1Ab transgenic rice(GM) and its parental non-cry1Ab rice(M) has been on-going since 2014. The diversity of the bacterial communities and the abundance of the microbial functional genes which drive the conversion of nitrogen in paddy soil were analyzed during the growth period of rice in the fifth year of the experiment, using 16 S rRnabased Illumina Mi Seq and real-time PCR on the amoA, nirS and nirK genes. The results showed no differences in the alpha diversity indexes of the bacterial communities, including Chao1, Shannon and Simpson, between the fields cultivated with line GM and cultivar M at any of the growth stages of rice. However, the bacterial communities in the paddy soil with line GM were separated from those of paddy soil with cultivar M at each of the growth stages of rice, based on the unweighted Uni Frac NMDS or PCoA. In addition, the analyses of ADONIS and ANOSIM, based on the unweighted Uni Frac distance, indicated that the above separations between line GM and cultivar M were statistically significant(Pnal gene prediction based on Illumina Mi Seq data suggested that the abundance of many functional genes increased in the paddy soil with line GM at the maturity stage of rice, such as genes related to the metabolism of starch, amino acids and nitrogen. Otherwise, the copies of bacterial amo A gene, archaeal amo A gene and denitrifying bacterial nir K gene significantly increased(Pnal genes in the paddy soil.

关键词： cry1Ab transgenic rice bacterial community microbial functional gene Illumina MiSeq Platform real-time PCR

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基于美欧医疗器械上市后法规要求对我国建立医疗器械警戒制度的思考

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中国食品药品监管 2024年第2期 94-103页

作者：李尧卞蓉蓉焦灵利李明宋雅娜郑立佳李栋赵一飞赵燕江苏省药品不良反应监测中心国家药品监督管理局药品评价中心国家药品监督管理局药物警戒研究与评价重点实验室

本文旨在深入探讨美国和欧盟的医疗器械上市后监管制度,包括风险监管理念、监管法规体系、上市后临床研究、质量管理体系等,总结出开发风险监测工具、落实风险管理、采用合并报告模式、公开风险信息等经验,为我国医疗器械行业有序发展... 详细信息

本文旨在深入探讨美国和欧盟的医疗器械上市后监管制度,包括风险监管理念、监管法规体系、上市后临床研究、质量管理体系等,总结出开发风险监测工具、落实风险管理、采用合并报告模式、公开风险信息等经验,为我国医疗器械行业有序发展提供参考。我国可以借鉴美欧医疗器械上市后的监管实践,从提高监管机构能力、建设监测哨点和强化法规框架等方面,建立和试点医疗器械警戒制度。

关键词：医疗器械警戒制度不良事件监测风险试点

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An active learning workflow for predicting hydrogen atom adsorption energies on binary oxides based on local electronic transfer features

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Green Energy & Environment 2024年第10期9卷 1489-1496页

作者： Wenhao Jing Zihao Jiao Mengmeng song ya Liu Liejin Guo International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Department of Energy and Power Engineering Shandong University of Technology

Machine learning combined with density functional theory（DFT） enables rapid exploration of catalyst descriptors space such as adsorption energy, facilitating rapid and effective catalyst screening. However, there is still a lack of models for predicting adsorption energies on oxides,due to the complexity of elemental species and the ambiguous coordination environment. This work proposes an active learning workflow（Le NN） founded on local electronic transfer features（e） and the principle of coordinate rotation invariance. By accurately characterizing the electron transfer to adsorption site atoms and their surrounding geometric structures, Le NN mitigates abrupt feature changes due to different element types and clarifies coordination environments. As a result, it enables the prediction of *H adsorption energy on binary oxide surfaces with a mean absolute error（MAE） below 0.18 e V. Moreover, we incorporate local coverage（θl） and leverage neutral network ensemble to establish an active learning workflow, attaining a prediction MAE below 0.2 e V for 5419 multi-*H adsorption structures. These findings validate the universality and capability of the proposed features in predicting *H adsorption energy on binary oxide surfaces.

关键词： Machine learning Adsorption energy Binary oxide Electron transfer Active learning

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柴油机加氢降低多环芳烃的数值研究

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工程热物理学报 2009年第8期30卷 1408-1410页

作者：宋雅娜龚景松钟北京清华大学航天航空学院北京100084

为实现柴油机节能减排目标,结合燃料热解方法向柴油机中加入微量氢气是一种新思路。本文以数值研究方法,基于简化的包含多环芳烃生成的正庚烷氧化反应机理,通过三维CFD模拟方法研究了不同微量氢气添加量下柴油机燃烧室内的温度、压力曲... 详细信息

为实现柴油机节能减排目标,结合燃料热解方法向柴油机中加入微量氢气是一种新思路。本文以数值研究方法,基于简化的包含多环芳烃生成的正庚烷氧化反应机理,通过三维CFD模拟方法研究了不同微量氢气添加量下柴油机燃烧室内的温度、压力曲线,以及典型多环芳烃生成曲线。计算研究结果表明,加入适当的微量氢气明显改善了柴油机燃烧室内的燃烧特性,并且可以使多环芳烃排放水平在一定数量级程度上得到减少。

关键词：柴油机多环芳烃氢气热解

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Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang Kai-Ning Shi yao-yao Shi Yi-Hui song Zhe He ya-song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

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Multimodal Fusion of Brain Imaging Data: Methods and Applications

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Machine Intelligence Research 2024年第1期21卷 136-152页

作者： na Luo Weiyang Shi Zhengyi yang Ming song Tianzi Jiang Brainnetome Center and national Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Brain Science and Intelligence Technology Institute of AutomationChinese Academy of SciencesBeijing 100190China Research Center for Augmented Intelligence Zhejiang LaboratoryHangzhou 311100China

Neuroimaging data typically include multiple modalities,such as structural or functional magnetic resonance imaging,dif-fusion tensor imaging,and positron emission tomography,which provide multiple views for observing and analyzing the *** lever-age the complementary representations of different modalities,multimodal fusion is consequently needed to dig out both inter-modality and intra-modality *** the exploited rich information,it is becoming popular to combine multiple modality data to ex-plore the structural and functional characteristics of the brain in both health and disease *** this paper,we first review a wide spectrum of advanced machine learning methodologies for fusing multimodal brain imaging data,broadly categorized into unsupervised and supervised learning *** by this,some representative applications are discussed,including how they help to under-stand the brain arealization,how they improve the prediction of behavioral phenotypes and brain aging,and how they accelerate the biomarker exploration of brain ***,we discuss some exciting emerging trends and important future ***,we intend to offer a comprehensive overview of brain imaging fusion methods and their successful applications,along with the chal-lenges imposed by multi-scale and big data,which arises an urgent demand on developing new models and platforms.

关键词： Multimodal fusion supervised learning unsupervised learning brain atlas cognition brain disorders

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大流量、高压航天反力式涡轮最佳通道气动设计

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宇航学报 2006年第5期27卷 839-842页

作者：宋雅娜张国舟北京航空航天大学宇航学院北京100083

基于闭式补燃循环液体火箭发动机流量大的特点,欲设计效率水平高的航天反力式涡轮。因涡轮进出口压力均很高,而膨胀比小、载荷系数大,为保证较高的涡轮效率水平,对涡轮气动设计方法进行了优化。在涡轮进口总温、总压、转速和功率一定条... 详细信息

基于闭式补燃循环液体火箭发动机流量大的特点,欲设计效率水平高的航天反力式涡轮。因涡轮进出口压力均很高,而膨胀比小、载荷系数大,为保证较高的涡轮效率水平,对涡轮气动设计方法进行了优化。在涡轮进口总温、总压、转速和功率一定条件下,以AMDC/KQ涡轮叶栅损失模型为基础,依据涡轮中径的一维气动计算,对涡轮子午通道、叶栅通道及叶栅造型几组参数组合分别进行了气动设计的优化,研究了涡轮中径、叶高、叶栅稠度、导动叶喉宽匹配及动叶进口构造角对涡轮效率的影响,实现了涡轮效率水平最高。

关键词：液体火箭发动机涡轮

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直喷式柴油机燃烧过程及碳烟生成的初步计算

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工程热物理学报 2008年第2期29卷 339-342页

作者：宋雅娜钟北京席军清华大学航天航空学院北京100084

依据已简化的包含多环芳烃生成的正庚烷气相详细化学反应机理,基于专业流体解析软件FLUENT6.3对直喷式柴油机压缩、膨胀冲程内的自燃和燃烧过程进行了动态模拟,得到了缸内平均温度、主要反应物以及中间产物多环芳烃生成量随转角变化的... 详细信息

依据已简化的包含多环芳烃生成的正庚烷气相详细化学反应机理,基于专业流体解析软件FLUENT6.3对直喷式柴油机压缩、膨胀冲程内的自燃和燃烧过程进行了动态模拟,得到了缸内平均温度、主要反应物以及中间产物多环芳烃生成量随转角变化的特性曲线。在数值上,计算得到以苯环质量为主的多环芳烃总生成量水平比试验测量结果约高出1～2个量级,但是在随转角变化的特性上,计算与试验测量曲线定性趋势一致。针对特定转角时刻主要火焰结构参数的截面分布,分析研究了柴油机缸内化学反应特性与流体流动相互作用下的空间分布特征。通过耦合详细碳烟粒子动力学模型,对碳烟表象尺寸进行了初步模拟。

关键词：柴油机正庚烷氧化反应多环芳烃碳烟

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