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Molecular Characterization and Functional Analysis of OsPHY1,a Purple Acid Phosphatase (PAP)-Type Phytase Gene in Rice (Oryza sativa L.)

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Journal of Integrative Agriculture 2012年第8期11卷 1217-1226页

作者： li Rui-juan LU Wen-jing GUO Cheng-jin li xiao-juan GU Jtm-tao xiao Kai College of life Sciences Agricultural University ofHebei Baoding 071001 P.R. China College of Agronomy Agricultural University of Hebei Baoding 071001 P.R. China

As a specific type of acid phosphatses, phytases play diverse roles in plants by catalazing the degradation of phytic acid and its derivatives. In this study, a rice phytase gene referred to OsPHY1 has been functionally characterized. OsPHY1 contains a 1 620 bp of open reading frame, encoding a 539-aa polypeptide. A conserve domain metallophosphatase （MPP）（MPP_PAPs）, generally harbored in phytase and purple acid phosphatases （PAP）, was identified in OsPHY1 （residue 194-398）. Phylogenetic analysis revealed that OsPHY1 shares high similarities with phytase genes and PAP-type genes that derived from diverse plant species. The OsPHY1 transcripts were detected to be abundant in germinating seeds, suggesting that this gene plays potential roles on degradation of seed phytic acid and its derivatives during the germination process. Biochemical analysis confirmed that OsPHY1 possesses strong catalytic activities on phytic acid-Na2, with optimal temperature of 57°C and suitable pH of 3.5. Based on transgene analysis, the putative role of OsPHY1 in plants on utilization of phytate was assessed. Under the condition that phytic acid-Na2 was used as sole P source, the OsPHY1-overexpressing tobacco plants behaved higher phytase activities, higher concentrations of Pi, more accumulative amount of total phosphorus, and much more improved growth traits than those of the control plants. Therefore, OsPHY1 is acted as an important component on degradation of the phytins during the seed germination process in rice. Also, OsPHY1 has a potential use on generation of elite crop germplasms with improved use efficiencies on phytate and its derivatives.

关键词： rice (Oryza sitava L.) phytase expression transgenic tobacco phosphorus utilization efficiency

数智技术赋能课后服务高质量发展的逻辑理性与实践路向

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现代教育技术 2025年第2期35卷 108-116页

作者：梁中锋李小娟章光琼陈亮曹天生华中师范大学人工智能学部湖北武汉430079 河南师范大学教育学部河南新乡453007 华中师范大学出版社有限责任公司湖北武汉430079

高质量的课后服务是促进学生个性化全面发展,与课内教学协同推进基础教育高质量发展的重要基础。然而,当前课后服务存在目标偏离风险凸显、主体价值共创缺失、学生全息评价困难的问题。为此,文章在分析课后服务高质量发展内涵和现实挑... 详细信息

高质量的课后服务是促进学生个性化全面发展,与课内教学协同推进基础教育高质量发展的重要基础。然而,当前课后服务存在目标偏离风险凸显、主体价值共创缺失、学生全息评价困难的问题。为此,文章在分析课后服务高质量发展内涵和现实挑战的基础上,从人机数智融合的适应性服务视角,厘定了以“清作业,保托管”为实践起点、“完整人”培育为价值旨归、人机数智融合“场域”为发展载体的课后服务高质量发展的实践逻辑。参照此逻辑理性,文章探究了数智技术在公共数字化资源供给体系构建、课后服务评价监管机制构建、家校社协同机制完善、城乡/县区协同发展机制完善、五育类课程师资智力模式形成共五个方面的赋能课后服务高质量发展的实践路向,以期为学校课后服务数字化治理与创新人才培养提供参考。

关键词：课后服务数智技术逻辑理性实践路向高质量发展

Molecular Characterization and Expression Analysis of TaZFP15, a C_2H_2-Type Zinc Finger Transcription Factor Gene in Wheat (Triticum aestivum L.)

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Journal of Integrative Agriculture 2012年第1期11卷 31-42页

作者： SUN Zhao-hua DING Chang-huan li xiao-juan xiao Kai College of life Science Agricultural University ofHebei Baoding 071001 P.R.China College of Agronomy Agrieultural University of Hebei Baoding 071001 P.R. China

Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.

关键词： Triticum aestivum L. zinc-finger transcription factor gene nutrition deficiency abiotic stress expression pattern

Interface Mechanical Behavior of Flexible Piles Under Lateral Loads in OWT Systems

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China Ocean Engineering 2023年第3期37卷 484-494页

作者： li xiao-juan ZHU Ming-xing DAI Guo-liang WANG li-yan liU Jing School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212003China School of Civil Engineering Southeast UniversityNanjing 210096China Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Southeast UniversityNanjing 211189China

This paper investigates the interface mechanical behavior of flexible piles with L_p/D>10 under lateral load and an overturning moment in monotonic loading *** modify the beam-on-Winkler-foundation model of piles in offshore wind farms,the energy-based variational method is *** soil is treated as a multi-layered elastic continuum with the assumption of three-dimensional displacements,the pile modeled as an Euler-Bernoulli beam.A series of cases using MATLAB programming was conducted to investigate the simplified equations of initial *** results indicated that the interaction between soil layers and the applied force position should be taken into account in calculating the horizontal soil ***,the distributed moment had a limiting effect on the lateral capacity of a flexible ***,to account for the more realistic conditions of OWT systems,field data from the Donghai Bridge offshore wind farm were used.

关键词： flexible piles interface mechanical behavior initial stiffness p-y curves offshore wind turbine systems

A Simplified Method for Estimating the Initial Stiffness of Monopile-Soil Interaction Under Lateral Loads in Offshore Wind Turbine Systems

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China Ocean Engineering 2023年第1期37卷 165-174页

作者： li xiao-juan DAI Guo-liang ZHU Ming-xing WANG li-yan liU Hong-yuan School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212003China School of Civil Engineering Southeast UniversityNanjing 210096China Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Southeast UniversityNanjing 211189China

The interface mechanical behavior of a monopile is an important component of the overall offshore wind turbine structure *** the soil-structure interaction,particularly the initial soil-structure stiffness,has a significant impact on the study of natural frequency and dynamic response of the *** this paper,a simplified method for estimating the interface mechanical behavior of monopiles under initial lateral loads is *** on the principle of minimum potential energy and virtual work theory,the functions of soil reaction components at the interface of monopiles are derived;MATLAB programming has been used to simplify the functions of the initial stiffness by fitting a large number of examples;then the functions are validated against the field test data and FDM *** method can modify the modulus of the subgrade reaction in the p-y curve method for the monopile-supported offshore wind turbine system.

关键词： theoretical analysis pile−soil interaction interface mechanical behavior offshore wind turbine systems

Interaction Between Elements Nb and Mo During Precipitation in Microalloyed Austenite

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Journal of Iron and Steel Research International 2010年第9期17卷 60-63页

作者： YUAN Shao-qiang liANG Guo li ZHANG xiao-juan Department of Eleetromeehanieal Engineering Tangshan College Tangshan 063000 Hebei China

Thermo-simulation test and transmission electron microscopy （TEM） have been used to investigate the interaction between the microalloying elements Nb and Mo within the precipitates during relaxation after austenite deformation of C-Ti-Mo steel and C-Nb-Mo steel. The experimental results demonstrated that the austenitic structure was preserved both in C-Ti-Mo steel and C-Nb-Mo steel even if they were relaxed for 1000 s after deformation at 850℃. The strainqnduced precipitate occurs in two kinds of steel. Through the energy spectrum analysis, it was found that the precipitates were Ti（C, N） and Mo-bearing Nb（C, N） respectively and there exists a strong affinity of Mo for Nb with in the precipitates. Mo atoms would enter the lattice of Nb（C, N） particles probably after Nb（C, N） formation.

关键词： thermo-simulation microstructure strain-induced precipitation relaxation carbonitride

A Time-Marching Throughflow Model and its Application in Transonic Axial Compressor

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Journal of Thermal Science 2010年第6期19卷 519-525页

作者： JIN Hai-liang JIN Dong-hai li xiao-juan GUI Xing-min Aeroengine Numerical Simulation Research Center Beihang University Beijing China The College of Engineering Peking University Beijing China

A throughflow model based on the time-marching finite volume approach is described in this paper. The governing equations are derived by circumferentially averaging the three-dimensional Navier-Stokes equations neglecting the circumferentially non-uniform and viscous terms. An inviscid blade force model similar to the Large-particle method is derived. The viscous blade force has been modeled by the distributed loss model. The convective fluxes of the governing equation are discretized with the Edward’s low-diffusion flux-splitting (LDFSS) scheme. And a point-iterative Symmetric Gauss-Seidel (SGS) scheme is used in the temporal discretization. The throughflow model has been applied to the NASA Rotor 67 and a high-load transonic fan stage ATS-2. The reasonable good agreements with the experiments and the 3D viscous computations show the potential of the method.

关键词： throughflow model time marching transonic axial compressor

Latitudinal patterns of climatic variables and influence of local topography on climatic variables in the dry valleys of southwestern China

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Journal of Mountain Science 2022年第5期19卷 1348-1356页

作者： li xiao-juan liU Xin ZHANG Han-yue BAO Wei-kai CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Climate is a key factor to determine the pattern of ecosystems;however,the latitudinal patterns of climatic variables in the arid and semiarid areas remain largely unclear when compared to humid *** topography of the dry valleys of southwestern China plays an important role in the formation of ***,its impact on the climate remains *** this study,eight climatic variables from 12 meteorological stations were analyzed to explore their latitudinal patterns in the wet and dry seasons from 1961 to *** also quantified the effects of local topography(RH10)on the climatic *** results were as follows:sunshine duration,total solar radiation,average temperature,and evaporation decreased significantly,and wind speed increased significantly with increasing latitude in the annual,wet,and dry seasons(P<0.001).Relative humidity and precipitation decreased significantly with increasing latitude in the wet season(P<0.001),and no obvious change pattern was observed in the dry *** index significantly decreased(toward dryness)with increasing latitude in the wet season and increased in the dry season(P<0.001).Wind speed had a significantly positive relationship with topography(RH10)(P<0.01),whereas precipitation and aridity index were negatively associated with topography in the wet season and positively associated with topography in the dry *** was positively associated with RH10 in the wet season,and negatively in the dry *** results of our research could provide new perspectives for understanding the relationship between topography and drought in the dry valleys of southwestern China.

关键词： Latitudinal patterns Wet season Dry season Aridity index Local topography

Identification of Organic Substances Associated with Tissue Senescence in Upland Cotton (Gossypium spp. L.) Based on GC-MS Analysis

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Agricultural Sciences in China 2011年第8期10卷 1197-1205页

作者： XU Zhen-long GUO Cheng-jin GU Jun-tao LU Wen-jing li xiao-juan xiao Kai College of Agronomy Agricultural University of HebeiBaoding 071001P.R.China College of life Science Agricultural University of HebeiBaoding 071001P.R.China

Premature senescence in crop production,especially occurred at the late growth stage,generally results in a reduction in yield and ***,it is beneficial for yield and quality to properly delay senescence of plant tissues during the late developmental *** this study,it was observed that the chlorophyll content and photosynthetic rate were gradually decreased along leaf growth progression,and the rates of reduction were promoted by *** on gas chromatography-mass spectrometry （GC-MS） analysis,total eight,five,seven,and five kinds of organic compounds that putatively associated with the tissue senescent progression were identified in leaves,fruit branches,petals,and sepals,*** was found that the identified organic compound,such as a-pinene,b-pinene,and pentadecane were present in different *** the total ten organic substances identified to be related with the leaf senescence,half were specifically detected in the drought *** results suggest some biochemical pathways associated with the leaf senescence are distinctly regulated by *** identified organic compounds in the tested tissues showed three types on the performance pattern based on the contents along with the senescent progression,including gradually increasing,decreasing,and a curve with one single ***,during the senescence process in tissues,a subset of metabolic substances occur modifications on the quantities,reflecting a complicate biochemical reactions are initiated via the senescence *** analysis of the important organic substances will be helpful for elucidation of the tissue senescence mechanism at the biochemical level and provide a new insight of the senescence signaling transductions in cotton.

关键词： cotton (Gossypium spp. L.) senescence organic substance identification