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The soft glumes of common wheat are sterile-lemmas as determined by the domestication gene Q 被引量:1
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作者 Gaoyuan Song Guoliang Sun +7 位作者 Xingchen Kong Meiling Jia Ke Wang Xingguo Ye Yun Zhou Shuaifeng Geng Long Mao Aili Li 《The Crop Journal》 SCIE CAS CSCD 2019年第1期113-117,共5页
The Q gene in common wheat encodes an APETALA2(AP2) transcription factor that causes the free threshing attribute. Wheat spikelets bearing several florets are subtended by a pair of soft glumes that allow free liberat... The Q gene in common wheat encodes an APETALA2(AP2) transcription factor that causes the free threshing attribute. Wheat spikelets bearing several florets are subtended by a pair of soft glumes that allow free liberation of seeds. In wild species, the glumes are tough and rigid,making threshing difficult. However, the nature of these "soft glumes", caused by the domestication allele Q is not clear. Here, we found that over expression of Q in common wheat leads to homeotic florets at glume positions. We provide phenotypic, microscopy, and marker genes evidence to demonstrate that the soft glumes of common wheat are in fact lemma-like organs, or so-called sterile-lemmas. By comparing the structures subtending spikelets in wheat and other crops such as rice and maize, we found that AP2 genes may play conserved functions in grasses by manipulating vestigial structures, such as floret-derived soft glumes in wheat and empty glumes in rice. Conversion of these seemingly vegetative organs to reproductive organs may be useful in yield improvement of crop species. 展开更多
关键词 FLORET development SPIKE morphology STERILE LEMMA Wheat
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Arithmetic Progressions,Different Regularity Lemmas and Removal Lemmas
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作者 Endre Szemerédi 《Communications in Mathematics and Statistics》 SCIE 2015年第3期315-328,共14页
This lecture note is mainly about arithmetic progressions,different regularity lemmas and removal lemmas.We will be very brief most of the time,trying to avoid technical details,even definitions.For most technical det... This lecture note is mainly about arithmetic progressions,different regularity lemmas and removal lemmas.We will be very brief most of the time,trying to avoid technical details,even definitions.For most technical details,we refer the reader to references.Apart from arithmetic progressions,we also discuss property testing and extremal graph theory. 展开更多
关键词 Arithmetic progressions Regularity lemmas Removal lemmas
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ELE restrains empty glumes from developing into lemmas 被引量:12
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作者 Lilan Hong Qian Qian +6 位作者 Keming Zhu Ding Tang Zejun Huang Ling Gao Ming Li Minghong Gu Zhukuan Cheng 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第2期101-115,共15页
Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a ... Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a vast and largely inconclusive discussion. Here we provide some direct evidence to support the idea that the empty glumes of rice (Oryza sativa) are counterparts of lemmas. We show that the development of empty glumes is regulated by ELE (elongated empty glume), which belongs to a plant specific novel gene family. Mutations at the ELE locus cause elongated empty glumes, which mimic the lemmas and have the epidermal morphology of lemmas with four or five vascular bundles. As a nuclear-localized gene, ELE is specifically expressed at the empty glumes of immature spikelets, and its ectopic expression causes many floral development defects, including lemma-like palea, extra palea-like structures, elongated lodicules, extra stamens and stigmas. Our result suggests that empty glumes are lemmas of the sterile florets located at the lateral side of the rice spikelet, and ELE acts as a regulator restraining its growth to maintain its small size in wild-type plants. 展开更多
关键词 empty glumes lemmas ELE RICE
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A generalization of Banach's lemma and its applications to perturbations of bounded linear operators
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作者 WANG Zi DING Jiu WANG Yu-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期363-369,共7页
Let X be a Banach space and let P:X→X be a bounded linear operator.Using an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear ... Let X be a Banach space and let P:X→X be a bounded linear operator.Using an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear operator on X,and a bound on its spectral radius is also obtained.This generalizes the classic Banach lemma.We apply the result to the perturbation analysis of general bounded linear operators on X with commutative perturbations. 展开更多
关键词 Banach lemma spectral radius generalized inverse perturbation analysis
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A Finite-Time Convergent Analysis of Continuous Action Iterated Dilemma
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作者 Zhen Wang Xiaoyue Jin +1 位作者 Tao Zhang Dengxiu Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期563-565,共3页
Dear Editor,In this letter, a finite-time convergent analysis of continuous action iterated dilemma(CAID) is proposed. In traditional evolutionary game theory, the strategy of the player is binary(cooperation or defec... Dear Editor,In this letter, a finite-time convergent analysis of continuous action iterated dilemma(CAID) is proposed. In traditional evolutionary game theory, the strategy of the player is binary(cooperation or defection), which limits the number of strategies a player can choose from. 展开更多
关键词 LEMMA LETTER CONVERGENT
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THE BOUNDARY SCHWARZ LEMMA AND THE RIGIDITY THEOREM ON REINHARDT DOMAINS B_(p)^(n) OF C^(n)
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作者 王建飞 张艳慧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期839-850,共12页
By introducing the Carathéodory metric,we establish the Schwarz lemma at the boundary for holomorphic self-mappings on the unit p-ball B_(p)^(n) of C^(n).Furthermore,the boundary rigidity theorem for holomorphic ... By introducing the Carathéodory metric,we establish the Schwarz lemma at the boundary for holomorphic self-mappings on the unit p-ball B_(p)^(n) of C^(n).Furthermore,the boundary rigidity theorem for holomorphic self-mappings defined on B_(n)^(p) is obtained.These results cover the boundary Schwarz lemma and rigidity result for holomorphic self-mappings on the unit ball for p=2,and the unit polydisk for p=∞,respectively. 展开更多
关键词 Schwarz lemma Carathéodory metric RIGIDITY
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Rice AGL1 determines grain size and sterile lemma identity
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作者 Haiping Yu An Wang +4 位作者 Guangheng Zhang Guojun Dong Longbiao Guo Qian Qian Deyong Ren 《The Crop Journal》 SCIE CSCD 2024年第2期630-634,共5页
The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in ... The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in rice are far from established.Here,we isolated rice gene,AGL1 that controlled grain size and determines the fate of the sterile lemma.Loss of function of AGL1 produced larger grains and reduced the size of the sterile lemma.Larger grains in the agl1 mutant were caused by a larger number of cells that were longer and wider than in the wild type.The sterile lemma in the mutant spikelet was converted to a rudimentary glume-like organ.Our findings showed that the AGL1(also named LAX1)protein positively regulated G1 expression,and negatively regulated NSG1 expression,thereby affecting the fate of the sterile lemma.Taken together,our results revealed that AGL1 played a key role in negative regulation of grain size by controlling cell proliferation and expansion,and supported the opinion that rudimentary glume and sterile lemma in rice are homologous organs. 展开更多
关键词 Abnormal grain and sterile lemma 1 Oryza sativa Grain size Rudimentary glume
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Bounded Real Lemmas for Fractional Order Systems 被引量:1
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作者 Shu Liang Yi-Heng Wei +2 位作者 Jin-Wen Pan Qing Gao Yong Wang 《International Journal of Automation and computing》 EI CSCD 2015年第2期192-198,共7页
This paper derives the bounded real lemmas corresponding to L∞norm and H∞norm(L-BR and H-BR) of fractional order systems. The lemmas reduce the original computations of norms into linear matrix inequality(LMI) probl... This paper derives the bounded real lemmas corresponding to L∞norm and H∞norm(L-BR and H-BR) of fractional order systems. The lemmas reduce the original computations of norms into linear matrix inequality(LMI) problems, which can be performed in a computationally efficient fashion. This convex relaxation is enlightened from the generalized Kalman-YakubovichPopov(KYP) lemma and brings no conservatism to the L-BR. Meanwhile, an H-BR is developed similarly but with some conservatism.However, it can test the system stability automatically in addition to the norm computation, which is of fundamental importance for system analysis. From this advantage, we further address the synthesis problem of H∞control for fractional order systems in the form of LMI. Three illustrative examples are given to show the effectiveness of our methods. 展开更多
关键词 Fractional order systems L∞norm H∞norm H∞control bounded real lemmas linear matrix inequality(LMI).
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Identities on q-Harmonic Numbers
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作者 Mengxiao Zhou Haitao Jin Huanhuan Zheng 《Journal of Applied Mathematics and Physics》 2024年第5期1796-1803,共8页
With the help of the classical Abel’s lemma on summation by parts and algorithm of q-hypergeometric summations, we deal with the summation, which can be written as multiplication of a q-hypergeometric term and q-harm... With the help of the classical Abel’s lemma on summation by parts and algorithm of q-hypergeometric summations, we deal with the summation, which can be written as multiplication of a q-hypergeometric term and q-harmonic numbers. This enables us to construct and prove identities on q-harmonic numbers. Several examples are also given. 展开更多
关键词 Harmonic Numbers q-Zeilberger Algorithm Abel’s Lemma
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National Security Dilemma in the Digital Era and the Building of a Community with a Shared Future in Cyberspace
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作者 Lang Ping 《Contemporary World》 2023年第5期28-31,共4页
A review of the history of human development shows that every major technological revolution brings new challenges to national security.With the advent of the information technology revolution represented by the Inter... A review of the history of human development shows that every major technological revolution brings new challenges to national security.With the advent of the information technology revolution represented by the Internet,cybersecurity has become an issue of paramount importance,and the digital intelligence revolution with digital technology innovations such as big data and cloud computing has further expanded the connotation and extension of cybersecurity. 展开更多
关键词 COMPUTING LEMMA expanded
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Modification of the Convergence of GG-PPA for Solving Generalized Equations
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作者 Asraful Alom Zaidur Rahman +1 位作者 Bayezid Gazi Imran Hossain 《Journal of Applied Mathematics and Physics》 2023年第1期260-275,共16页
A modified Gauss-type Proximal Point Algorithm (modified GG-PPA) is presented in this paper for solving the generalized equations like 0 &#8712;T(x), where T is a set-valued mapping acts between two different Bana... A modified Gauss-type Proximal Point Algorithm (modified GG-PPA) is presented in this paper for solving the generalized equations like 0 &#8712;T(x), where T is a set-valued mapping acts between two different Banach spaces X and Y. By considering some necessary assumptions, we show the existence of any sequence generated by the modified GG-PPA and prove the semi-local and local convergence results by using metrically regular mapping. In addition, we give a numerical example to justify the result of semi-local convergence. 展开更多
关键词 Set-Valued Mappings Metrically Regular Mappings Semi-Local Convergence Lipschitz Continuous Fixed Point Lemma
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A Proof of Brouwer’s Fixed Point Theorem Using Sperner’s Lemma
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作者 Cassie Lu 《数学计算(中英文版)》 2023年第2期1-6,共6页
This article offers a simple but rigorous proof of Brouwer’s fixed point theorem using Sperner’s Lemma.The general method I have used so far in the proof is mainly to convert the n-dimensional shapes to the correspo... This article offers a simple but rigorous proof of Brouwer’s fixed point theorem using Sperner’s Lemma.The general method I have used so far in the proof is mainly to convert the n-dimensional shapes to the corresponding case under the Sperner’s Labeling and apply the Sperner’s Lemma to solve the question. 展开更多
关键词 Brouwer’s Fixed Point Theorem Sperner’s Lemma PROOF
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汉语名词短语产生中的量词一致性效应 被引量:12
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作者 王黎 郭佳 +1 位作者 毕彦超 舒华 《心理与行为研究》 2006年第1期34-38,共5页
目前,语言产生领域的多数研究都集中在口语词语产生方面,许多研究者针对不同的语言系统的特色,对功能词进行了大量跨语言的研究。汉语量词是汉藏语系独有的功能词,本研究采用词图干扰范式,以名词短语和简单名词两种不同的图片命名任务,... 目前,语言产生领域的多数研究都集中在口语词语产生方面,许多研究者针对不同的语言系统的特色,对功能词进行了大量跨语言的研究。汉语量词是汉藏语系独有的功能词,本研究采用词图干扰范式,以名词短语和简单名词两种不同的图片命名任务,探讨了汉语量词的产生过程。实验结果发现,在名词短语命名任务下,存在量词的一致性效应;在名词命名的任务下,则不存在这种一致性效应。研究还发现语义干扰效应在两种不同命名任务下出现了分离。语义干扰效应只在命名名词的任务下出现,在命名名词短语的任务下未被发现。 展开更多
关键词 语言产生 词汇通达 图片命名 LEMMA 量词一致性效应
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线性程序的Ranking函数自动合成 被引量:1
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作者 李骏 李轶 +1 位作者 冯勇 秦小林 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2009年第5期176-181,共6页
针对判定一个程序终止性的经典方法Ranking函数法,运用半代数系统的概念,把程序终止性问题转换为求半代数系统的Ranking函数。然后运用符号计算工具DISCOV-ERER和Farkas引理,求出函数参数存在的充分必要条件,并根据符号计算理论的方法... 针对判定一个程序终止性的经典方法Ranking函数法,运用半代数系统的概念,把程序终止性问题转换为求半代数系统的Ranking函数。然后运用符号计算工具DISCOV-ERER和Farkas引理,求出函数参数存在的充分必要条件,并根据符号计算理论的方法自动合成Ranking函数。通过计算代数理论的证明和试验的验证,并与其他方法做了比较,这种方法是高效合理的。 展开更多
关键词 DISCOVERER Farkas’lemma Ranking函数 半代数系统 程序终止性 程序验证
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Robustness Analysis of Discrete-time Indirect Model Reference Adaptive Control with Normalized Adaptive Laws 被引量:2
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作者 Qing-Zheng Gao Xue-Jun Xie 《International Journal of Automation and computing》 EI 2010年第3期381-388,共8页
For a class of discrete-time systems with unmodeled dynamics and bounded disturbance, the design and analysis of robust indirect model reference adaptive control (MRAC) with normalized adaptive law are investigated.... For a class of discrete-time systems with unmodeled dynamics and bounded disturbance, the design and analysis of robust indirect model reference adaptive control (MRAC) with normalized adaptive law are investigated. The main work includes three parts. Firstly, it is shown that the constructed parameter estimation algorithm not only possesses the same properties as those of traditional estimation algorithms, but also avoids the possibility of division by zero. Secondly, by establishing a relationship between the plant parameter estimate and the controller parameter estimate, some similar properties of the latter are also established. Thirdly, by using the relationship between the normalizing signal and all the signals of the closed-loop system, and some important mathematical tools on discrete-time systems, as in the continuous-time case, a systematic stability and robustness analysis approach to the discrete indirect robust MRAC scheme is developed rigorously. 展开更多
关键词 Discrete-time systems model reference adaptive control (MRAC) swapping lemmas STABILITY ROBUSTNESS
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THE ∂∂^(-)-BOCHNER FORMULAS FOR HOLOMORPHIC MAPPINGS BETWEEN HERMITIAN MANIFOLDS AND THEIR APPLICATIONS 被引量:1
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作者 汤凯 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1659-1669,共11页
In this paper,we derive some∂∂^(-)-Bochner formulas for holomorphic maps between Hermitian manifolds.As applications,we prove some Schwarz lemma type estimates,and some rigidity and degeneracy theorems.For instance,we... In this paper,we derive some∂∂^(-)-Bochner formulas for holomorphic maps between Hermitian manifolds.As applications,we prove some Schwarz lemma type estimates,and some rigidity and degeneracy theorems.For instance,we show that there is no non-constant holomorphic map from a compact Hermitian manifold with positive(resp.non-negative)ℓ-second Ricci curvature to a Hermitian manifold with non-positive(resp.negative)real bisectional curvature.These theorems generalize the results[5,6]proved recently by L.Ni on Kähler manifolds to Hermitian manifolds.We also derive an integral inequality for a holomorphic map between Hermitian manifolds. 展开更多
关键词 Schwarz lemmas Bochner formulas holomorphic map Hermitian manifolds ℓ-second Ricci curvature
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Goldbach数的例外集合(Ⅲ)
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作者 陈景润 刘健民 《Chinese Quarterly Journal of Mathematics》 CSCD 1989年第1期15+1-14,1-14,共15页
本文把能表成两个奇素数之和的偶数称为Goldbach数,以E(x)记作不超过x的非Goldbach数的数目,并且证明了E(x)=O(x^(0.95)
关键词 奇素数 INTEGER GOLDBACH LEMMA PROOF 陈景润 数学季刊 letter notes 石西
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New versions of Barbalat's lemma with applications 被引量:6
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作者 Mingzhe HOU Guangren DUAN Mengshu GUO 《控制理论与应用(英文版)》 EI 2010年第4期545-547,共3页
This note presents a set of new versions of Barbalat's lemma combining with positive (negative) definite functions.Based on these results,a set of new formulations of Lyapunov-like lemma are established.A simple ex... This note presents a set of new versions of Barbalat's lemma combining with positive (negative) definite functions.Based on these results,a set of new formulations of Lyapunov-like lemma are established.A simple example shows the usefulness of our results. 展开更多
关键词 Barbalat's lemma Lyapunov-like lemma
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A note on overshoot estimation in pole placements 被引量:5
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作者 DaizhanCHENG LeiGUO +1 位作者 YuandanLIN YuanWANG 《控制理论与应用(英文版)》 EI 2004年第2期161-164,共4页
In this note we show that for a given controllable pair (A, B) and any λ > 0, a gain matrix K can be chosen so that the transition matrix e {(A+BK)t} of the system x = (A + BK) x decays at the exponential rate e ?... In this note we show that for a given controllable pair (A, B) and any λ > 0, a gain matrix K can be chosen so that the transition matrix e {(A+BK)t} of the system x = (A + BK) x decays at the exponential rate e ?λt and the overshoot of the transition matrix can be bounded by Mλ L for some constants M and L that are independent of λ. As a consequence, for any h > 0, a gain matrix K can be chosen so that the magnitude of the transition matrix e (A+BK)t can be reduced by 1/2 (or by any given portion) over [0, h]. An interesting application of the result is in the stabilization of switched linear systems with any given switching rate. 展开更多
关键词 Linear system Transition matrix Squashing Lemma
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A NOTE ON SCHWARZ LEMMA FOR THE MODULUS OF HOLOMORPHIC MAPPINGS ON D 被引量:4
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作者 刘洋 戴绍虞 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期89-94,共6页
In this note, we consider a holomorphic mapping f from the unit disk C in C to p-ball B^p = {z∈C^n;i=1∑n|zi|p〈1,1〈p〈+∞. It is proved that for such f,| | |f||(z)|≤1-||f(z)||^2/1-|z|^2,z∈D. Th... In this note, we consider a holomorphic mapping f from the unit disk C in C to p-ball B^p = {z∈C^n;i=1∑n|zi|p〈1,1〈p〈+∞. It is proved that for such f,| | |f||(z)|≤1-||f(z)||^2/1-|z|^2,z∈D. The extremal problem is also discussed when p is an even number. This result extends some related results on Schwarz lemma. 展开更多
关键词 Schwarz lemma holomorphic mapping p-ball
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