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Multi-Environmental Genetic Analysis of Grain Size Traits Based on Chromosome Segment Substitution Line in Rice(Oryza sativa L.)

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Phyton-International Journal of Experimental Botany 2022年第5期91卷 943-958页

作者： Yujia Leng Shuilian wang ruoan wang Tao Tao Shuwen Jia Tao Song Lina Xu Xiuling Cai Sukui Jin Jiping Gao Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding Key Laboratory of Plant Functional Genomics of the Ministry of EducationJiangsu Key Laboratory of Crop Genetics and PhysiologyJiangsu Co-Innovation Center for Modern Production Technology of Grain CropsCollege of AgricultureYangzhou UniversityYangzhou225009China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China University of Chinese Academy of Sciences Beijing100049China Innovation Academy for Seed Design Chinese Academy of SciencesBeijing100101China

Grain size traits are critical agronomic traits which directly determine grain yield,but the genetic bases of these traits are still not well *** this study,a total of 154 chromosome segment substitution lines(CSSLs)population derived from a cross between a japonica variety Koshihikari and an indica variety Nona Bokra was used to investigate grain length(GL),grain width(GW),length-width ratio(LWR),grain perimeter(GP),grain area(GA),and thousand grain weight(TGW)under four *** mapping analysis of six grain size traits was performed by QTL IciMapping 4.2 with an inclusive composite interval mapping(ICIM)model.A total of 64 QTLs were identified for these traits,which mapped to chromosomes 1,2,3,4,6,7,8,10,11,and 12 and accounted for 1.6%–27.1%of the total phenotypic *** these QTLs,thirty-six loci were novel and seven QTLs were identified under four *** locus containing the known grain size gene,qGL3/GL3.1/OsPPKL1,also have been ***,five pairs of digenic epistatic interactions were identified except for GL and *** findings will facilitate fine mapping of the candidate gene and QTL pyramiding to genetically improve grain yield in rice.

关键词： Rice grain size quantitative trait loci epistatic chromosome segment substitution lines

漏斗胸治疗中行NUSS微创手术术后恢复效果及复发控制作用分析

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中外女性健康研究 2024年第3期 21-24页

作者：蒋寅刘连波唐振霆范明郑俊强王若男刘峰无锡市儿童医院心胸外科江苏无锡214023 无锡市人民医院胸外科江苏无锡214023

目的:探讨NUSS微创手术在漏斗胸患儿中的应用效果。方法:选择2019年1月至2021年12月本院收治的52例漏斗胸患儿,根据随机数表法将其分为A组和B组,每组26例,A组予以改良Ravitch手术治疗,B组采用微创Nuss手术治疗。观察两组疗效、心功能水... 详细信息

目的:探讨NUSS微创手术在漏斗胸患儿中的应用效果。方法:选择2019年1月至2021年12月本院收治的52例漏斗胸患儿,根据随机数表法将其分为A组和B组,每组26例,A组予以改良Ravitch手术治疗,B组采用微创Nuss手术治疗。观察两组疗效、心功能水平、围术期恢复及术后复发情况。结果:B组总有效率(100.00%)与A组(96.15%)差异不明显(P>0.05);两组患儿术后1周各项心功能指标均高于本组术前,且B组左室射血分数(LVEF)及每搏输出量(SV)水平高于A组,差异明显(P0.05);B组术后1年复发率发生率较A组低,差异明显(P<0.05)。结论:NUSS微创手术及改良Ravitch手术为临床治疗漏斗胸患儿有效的、安全的术式,但前者更有助于促进患儿术后恢复,且对于控制患儿术后复发更具优势。

关键词：漏斗胸 NUSS微创手术改良Ravitch手术

平凉黄土高原沟壑区最高最低气温对气候变暖的响应

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干旱区资源与环境 2010年第6期24卷 72-76页

作者：王若安中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室中国气象局干旱气候变化与减灾重点开放实验室兰州730020 甘肃省平凉市气象局平凉744000

利用平凉黄土高原沟壑区7站1959-2008年平均最高、最低气温资料,采用线性倾向估计法和累积距平法,分析了最高、最低气温和日较差的长期变化趋势,对气候变化过程有了进一步的认识,用Mann-Kendall法对气候突变进行了检测。结果显示:平均... 详细信息

利用平凉黄土高原沟壑区7站1959-2008年平均最高、最低气温资料,采用线性倾向估计法和累积距平法,分析了最高、最低气温和日较差的长期变化趋势,对气候变化过程有了进一步的认识,用Mann-Kendall法对气候突变进行了检测。结果显示:平均最高、最低气温呈上升趋势,与全球和全国变暖趋势一致,气温日较差与全国减小趋势相反;气候的变化过程分三个阶段,20世纪70年代以前为气候偏冷期,80年代开始转暖,90年代明显变暖;最高、最低气温分别在1999年和1994年发生变暖突变。

关键词：气候变暖黄土高原沟壑区最高气温最低气温

黄土高原半干旱草地近地层湍流温湿特征及总体输送系数

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高原气象 2015年第1期34卷 21-29页

作者：岳平张强赵文王胜史晋森王若安中国气象局兰州干旱气象研究所/甘肃省干旱气候变化与减灾重点实验室/中国气象局干旱气候变化与减灾重点开放实验室兰州730020 张掖国家气候观象台张掖734000 兰州大学大气科学学院兰州730000

利用兰州大学半干旱气候与环境观测站(简称SACOL站)2008年夏季晴天近地层湍流观测资料,分析了SACOL站近地层湍流温、湿统计特征,确定了大气动力学和热力学粗糙度长度,讨论了总体输送系数随大气稳定度的变化规律。结果表明,大气层结不稳... 详细信息

利用兰州大学半干旱气候与环境观测站(简称SACOL站)2008年夏季晴天近地层湍流观测资料,分析了SACOL站近地层湍流温、湿统计特征,确定了大气动力学和热力学粗糙度长度,讨论了总体输送系数随大气稳定度的变化规律。结果表明,大气层结不稳定条件下,无量纲温度和比湿脉动方差与稳定度Z/L之间均满足-1/3次规律;大气层结稳定条件下,温湿脉动方差总体趋势是随大气稳定度增加而减小。水汽通量全天大于零,最大值为0.063 g·m-2·s-1,地表日平均蒸发量为1.9 mm。中性条件下,黄土高原半干旱草地动力学粗糙度长度为6.6×10-3m,热力学粗糙度为1.85×10-5m。大气层结不稳定条件下,CD平均值为4.4×10-3,CH平均值为3.9×10-3;中性条件下,CD和CH平均值分别为4.2×10-3和2.8×10-3;层结稳定条件下,CD平均值为3.1×10-3,CH平均值为2.1×10-3,表明总体输送系数随稳定度的增大而减小。

关键词：黄土高原湍流特征粗糙度长度总体输送系数

我国西北地区多年降水的氢氧同位素分布特征研究

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水文 2015年第1期35卷 33-39,50页

作者：黄锦忠谭红兵王若安温夏伟河海大学地球科学与工程学院江苏南京210098 甘肃省平凉市气象局甘肃平凉744000

降水是干旱区水文循环研究不可缺少的水文要素,为了揭示我国西北地区大气降水的氢氧同位素时空分布特征,合理开展不同尺度水文循环研究和建立对比标准,系统搜集分析了乌鲁木齐、银川、张掖、兰州、平凉、西安和拉萨七个地区多年大气降... 详细信息

降水是干旱区水文循环研究不可缺少的水文要素,为了揭示我国西北地区大气降水的氢氧同位素时空分布特征,合理开展不同尺度水文循环研究和建立对比标准,系统搜集分析了乌鲁木齐、银川、张掖、兰州、平凉、西安和拉萨七个地区多年大气降水的氢氧同位素数据资料。分析结果表明：乌鲁木齐、银川、张掖和兰州四个地区的δ^18O值夏半年明显高于冬半年,从全年尺度上来看只是受到了温度效应的影响;而位于关中盆地的西安地区则由于复杂的水汽来源,冬半年表现出受温度效应的控制,夏半年转为雨量效应控制为主。平凉地区δ^18O与其它海拔相近地区（如兰州）相比5~9月份均偏负,这与平凉地区较弱的城市热岛效应有关。西北地区大气降水δD和δ^18O的变化范围均在全球大气降水的变化范围之内,除平凉和拉萨外,其它几个地区大气降水线方程的斜率和截距均小于全球大气降水线,说明这些地区的降水是在干旱环境下经历较强程度的蒸发条件下进行的,且在降水过程中还可能受到了局地二次蒸发凝结等水汽循环的影响。而该区域大气降水的氘盈余（d值）表现出冬半年高、夏半年低的特点,表明冬半年和夏半年水汽来源不同或者水源地的蒸发条件不同。

关键词：西北地区大气降水氢氧同位素分布特征

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan wang Jiang wang Shaoming HE Fei wang Qi wang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

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基于多物理量有限元模型的电磁阀失效分析

机械强度 2019年第5期41卷 1152-1158页

作者：李剑峰肖明清唐希浪石伟文王若安空军工程大学航空航天工程学院

针对电磁阀失效机理不明确,缺乏有效的故障分析手段和方法等问题,设计电磁阀加速寿命实验,提出了基于多物理量有限元模型的电磁阀失效分析方法。首先利用Ansys有限元软件建立电磁阀温度场模型,计算各部件温度分布;其次将计算得到的温度... 详细信息

针对电磁阀失效机理不明确,缺乏有效的故障分析手段和方法等问题,设计电磁阀加速寿命实验,提出了基于多物理量有限元模型的电磁阀失效分析方法。首先利用Ansys有限元软件建立电磁阀温度场模型,计算各部件温度分布;其次将计算得到的温度作为新的载荷加入机械应力场模型求解过程中,得出由热应力和机械应力共同作用下的耦合应力值;最后在综合分析温度与耦合应力对电磁阀影响的基础上,通过实验数据和仿真结果的对比,分析得出一种电磁阀缓变失效机制。结果表明:线圈产生高温易破坏线圈绝缘层,同时由高温产生的热应力与机械应力的耦合效应会对绝缘橡胶产生挤压,温度与耦合效应的共同影响导致线圈在相互接触过程中不断短路,直至铁芯所受电磁力低于其工作阀值时不能克服弹簧的弹力运动,最后造成电磁阀的缓变失效,实验测定结果与数值仿真结果相符合。该方法可广泛适用于其它类型电磁阀的故障分析,为电磁阀的可靠性设计和延寿研究提供参考。

关键词：多物理量 Ansys 有限元模型温度场耦合应力缓变失效

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory