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The lawc gene emerged de novo from conserved genomic elements and acquired a broad expression pattern in Drosophila
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作者 Roman O.Cherezov Julia E.Vorontsova +3 位作者 Elena E.Kuvaeva Angelina A.Akishina Ekaterina L.Zavoloka Olga B.Simonova 《Journal of Genetics and Genomics》 2025年第7期901-914,共14页
It has recently become evident that the de novo emergence of genes is widespread and documented for a variety of organisms.De novo genes frequently emerge in proximity to existing genes,forming gene overlaps.Here,we p... It has recently become evident that the de novo emergence of genes is widespread and documented for a variety of organisms.De novo genes frequently emerge in proximity to existing genes,forming gene overlaps.Here,we present an analysis of the evolutionary history of a putative de novo gene,lawc,which overlaps with the conserved Trf2 gene,which encodes a general transcription factor in Drosophila melanogaster.We demonstrate that lawc emerged approximately 68 million years ago in the 5'-untranslated region(UTR)of Trf2 and displays an extensive spatiotemporal expression pattern.One of the most remarkable features of the lawc evolutionary history is that its emergence was facilitated by the engagement of Drosophilidae-specific short,highly conserved regions located in Trf2 introns.This represents a unique example of putative de novo gene birth involving conserved DNA regions localized in introns of conserved genes.The observed lawc expression pattern may be due to the overlap of lawc with the 5'-UTR of Trf2.This study not only enriches our understanding of gene evolution but also highlights the complex interplay between genetic conservation and innovation. 展开更多
关键词 De novo gene Overlapping genes conserved regulatory element Expression pattern DROSOPHILA
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Lie Symmetries and Conserved Quantities for the Singular Lagrange System 被引量:5
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作者 梅凤翔 朱海平 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期11-14,共4页
The invariance of the ordinary differential equations under the infinitesimal transformations was used to study the Lie symmetries and conserved quantities for the singular Lagrange system. The determining equations, ... The invariance of the ordinary differential equations under the infinitesimal transformations was used to study the Lie symmetries and conserved quantities for the singular Lagrange system. The determining equations, the restriction equations of the Lie symmetries and the form of conserved quantities of the system are obtained. 展开更多
关键词 singular system Lie symmetry conserved quantity
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Conserved quantities from Lie symmetries for nonholonomic systems 被引量:2
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作者 张毅 薛纭 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期289-292,共4页
This paper presents a new method to seek the conserved quantity from a Lie symmetry without using either Lagrangians or Hamiltonians for nonholonomic systems. The differential equations of motion of the systems are es... This paper presents a new method to seek the conserved quantity from a Lie symmetry without using either Lagrangians or Hamiltonians for nonholonomic systems. The differential equations of motion of the systems are established. The definition of the Lie symmetrical transformations of the systems is given, which only depends upon the infinitesimal transformations of groups for the generalized coordinates. The conserved quantity is directly constructed in terms of the Lie symmetry of the systems. The condition under which the Lie symmetry can lead to the conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 analytical mechanics nonholonomic system SYMMETRY conserved quantity
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Lie Symmetries and Conserved Quantities of Holonomic Mechanical Systems in Terms of Quasi-Coordinatee 被引量:1
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作者 傅景礼 刘荣万 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期215-220,共6页
Aim To study the Lie symmetries and conserved quantities of holonomic mechanical systems in terms of qnasi-coordinates. Methods The definition of an infinitesimal generator for the holonomic mechanical systems in te... Aim To study the Lie symmetries and conserved quantities of holonomic mechanical systems in terms of qnasi-coordinates. Methods The definition of an infinitesimal generator for the holonomic mechanical systems in terms of quasi-coordinates was given. Lie's method of the invariance of ordinary differential equations under infinitesimal transformations was used. Results and Conclusion The determining equations of the Lie symmetries of holonomic mechanical systems in terms of quassi-coordinates are established. The structure equation and the form of conserved quantities are obtained. An example to illustrate the applicaiton of the result is given. 展开更多
关键词 analytical mechanics quasi-coordinate Lie symmetry conserved quantity
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Cloning and Expression of Conserved Sequences of cry Gene in E.coli Strain Rosetta(DE3) 被引量:1
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作者 罗翠平 李金华 +1 位作者 谢烨明 曾万勇 《Agricultural Science & Technology》 CAS 2012年第5期958-961,996,共5页
[Objective] The aim was to clone the conserved sequences of cry gene and express them in Rosetta (DE3). [Method] Specific primers were designed according to NCBI database information and the conserved sequences of c... [Objective] The aim was to clone the conserved sequences of cry gene and express them in Rosetta (DE3). [Method] Specific primers were designed according to NCBI database information and the conserved sequences of cry gene were amplified by PCR from Bt transgenic cotton. Then recombinant plasmids were constructed and expressed in E. coil strain Rosetta (DE3). Finally, the effects of different concentrations and inducing time of IPTG on the expression level of protein were investigated. [Result] Two conserved sequences (304 and 853 bp respectively) of cry gene were amplified. The result of SDS-PAGE confirmed that the recombinant plasmids pGEX-4t-I-304 and pGEX-4t-1-853 could express fusion proteins by IPTG induction and the molecular weight of protein products was 39 and 62.4 kDa respectively, which was in accordance with predicted result. The optimal protein ex- pression conditions were confirmed as induction with 0.15 mmol/L IPTG for 7 h. [Conclusion] This study prepared the ground for the further detection of Bt transgenic crops. 展开更多
关键词 Bt gene conserved sequence CLONING Prokaryotic expression
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Symmetries and conserved quantities of generalized Birkhoffian systems 被引量:3
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作者 张毅 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期146-150,共5页
Three kinds of symmetries and their corresponding conserved quantities of a generalized Birkhoffian system are studied. First, by using the invariance of the Pfaffian action under the infinitesimal transformations, th... Three kinds of symmetries and their corresponding conserved quantities of a generalized Birkhoffian system are studied. First, by using the invariance of the Pfaffian action under the infinitesimal transformations, the Noether theory of the generalized Birkhoffian system is established. Secondly, on the basis of the invariance of differential equations under infinitesimal transformations, the definition and the criterion of the Lie symmetry of the generalized Birkhoffian system are established, and the Hojman conserved quantity directly derived from the Lie symmetry of the system is given. Finally, by using the invariance that the dynamical functions in the differential equations of the motion of mechanical systems still satisfy the equations after undergoing the infinitesimal transformations, the definition and the criterion of the Mei symmetry of the generalized Birkhoffian system are presented, and the Mei conserved quantity directly derived from the Mei symmetry of the system is obtained. Some examples are given to illustrate the application of the results. 展开更多
关键词 generalized Birkhoffian system SYMMETRY conserved quantity
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Lie Symmetries and Conserved Quantities of Holonomic Systems with Remainder Coordinates 被引量:2
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作者 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期26-31,共6页
Aim To study the Lie symmetries and the consered quantities of the holonomic systems with remainder coordinates. Methods Using the invariance of the ordinary differential equations under the infinitesimal transformati... Aim To study the Lie symmetries and the consered quantities of the holonomic systems with remainder coordinates. Methods Using the invariance of the ordinary differential equations under the infinitesimal transformations to establish the determining equations and the restriction equations of the Lie symmetries of the systems. Results and Conclusion the structure equation and the form of conserved quantities were obtained. An example was given to illustrate the application of the result. 展开更多
关键词 analytical mechanics remainder coordinate Lie symmetry conserved quantity
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Lie Symmetry and Conserved Quantities for Nonholonomic Vacco Dynamical Systems 被引量:3
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作者 DING Ning FANG Jian-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期265-268,共4页
In this paper the Lie symmetry and conserved quantities for nonholonomic Vacco dynamical systems are studied. The determining equation of the Lie symmetry for the system is given. The general Hojman conserved quantity... In this paper the Lie symmetry and conserved quantities for nonholonomic Vacco dynamical systems are studied. The determining equation of the Lie symmetry for the system is given. The general Hojman conserved quantity and the Lutzky conserved quantity deduced from the symmetry are obtained. 展开更多
关键词 Vacco dynamical system Lie symmetry general Hojman conserved quantity Lutzky conserved quantity
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Conformal invariance and conserved quantity of third-order Lagrange equations for non-conserved mechanical systems 被引量:2
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作者 张明江 方建会 +2 位作者 路凯 张克军 李燕 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4650-4656,共7页
This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conf... This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conformal invariance of the system are presented. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The necessary and sufficient condition that conformal invaxiance of the system would have Lie symmetry under single-parameter infinitesimal transformations is obtained. The corresponding conserved quantity of conformal invariance is derived with the aid of a structure equation. Lastly, an example is given to illustrate the application of the results. 展开更多
关键词 conformal invariance conserved quantity third-order Lagrange equation non-conserved mechanical system
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Lie symmetries and conserved quantities for generalized Birkhoff system 被引量:2
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作者 梅凤翔 崔金超 《Journal of Beijing Institute of Technology》 EI CAS 2011年第3期285-288,共4页
To study Lie symmetry and the conserved quantity of a generalized Birkhoff system with additional terms, the determining equations of the Lie symmetry of the system is derived. A con- served quantity of Hojman' s typ... To study Lie symmetry and the conserved quantity of a generalized Birkhoff system with additional terms, the determining equations of the Lie symmetry of the system is derived. A con- served quantity of Hojman' s type and a Noether' s conserved quantity are deduced by the Lie symme- try under some conditions. One example is given to illustrate the application of the result. 展开更多
关键词 generalized Birkhoff system Lie symmetry Noether conserved quantity conservedquantity of Hojman' s type
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Lie Symmetries and Conserved Quantities of Systems of Relative Motion Dynamics
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作者 刘荣万 傅景礼 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期221-225,共5页
Aim To study the Lie symmetries and conserved quantities of the dynamical equationsof relative motion for holonomic mechanical systems. Methods Lie's method of the invariance of ordinary differential equations u... Aim To study the Lie symmetries and conserved quantities of the dynamical equationsof relative motion for holonomic mechanical systems. Methods Lie's method of the invariance of ordinary differential equations under infinitesimal transformations was used. Results and Conclusion The determining equaiton of the Lie symmetries for the dynamical equationS of relative motion is established.The structure quation and the form conserved quantities are obtained. An example iD illustrate the application of the result is given. 展开更多
关键词 analytical mechanics dynamical of relative motion Lie symmetry conserved quantity
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Mei Symmetry and Conserved Ouantity of Tzénoff Equations for Nonholonomic Systems of Non-Chetaev's Type 被引量:18
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作者 ZHENG Shi-Wang XIE Jia-Fang LI Yan-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期851-854,共4页
Mei symmetry of Tzenoff equations for nonholonomic systems of non-Chetaev's type under the infinitesimal transformations of groups is studied. Its definitions and discriminant equations of Mei symmetry are given. Suf... Mei symmetry of Tzenoff equations for nonholonomic systems of non-Chetaev's type under the infinitesimal transformations of groups is studied. Its definitions and discriminant equations of Mei symmetry are given. Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given. Hojman conserved quantity of Tzenoff equations for the systems through Lie symmetry in the condition of special Mei symmetry is obtained. 展开更多
关键词 nonholonomic system Tzenoff equations Mei symmetry conserved quantity
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Noether symmetry and conserved quantity for dynamical system with non-standard Lagrangians on time scales 被引量:12
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作者 宋静 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期201-209,共9页
This paper focuses on studying the Noether symmetry and the conserved quantity with non-standard Lagrangians, namely exponential Lagrangians and power-law Lagrangians on time scales. Firstly, for each case, the Hamilt... This paper focuses on studying the Noether symmetry and the conserved quantity with non-standard Lagrangians, namely exponential Lagrangians and power-law Lagrangians on time scales. Firstly, for each case, the Hamilton prin- ciple based on the action with non-standard Lagrangians on time scales is established, with which the corresponding Euler-Lagrange equation is given. Secondly, according to the invariance of the Hamilton action under the infinitesimal transformation, the Noether theorem for the dynamical system with non-standard Lagrangians on time scales is established. The proof of the theorem consists of two steps. First, it is proved under the infinitesimal transformations of a special one-parameter group without transforming time. Second, utilizing the technique of time-re-parameterization, the Noether theorem in a general form is obtained. The Noether-type conserved quantities with non-standard Lagrangians in both clas- sical and discrete cases are given. Finally, an example in Friedmann-Robertson-Walker spacetime and an example about second order Duffing equation are given to illustrate the application of the results. 展开更多
关键词 time scale non-standard Lagrangian Noether symmetry conserved quantity
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Symmetry and Hojman Conserved Quantity of Tznoff Equations for Unilateral Holonomic System 被引量:12
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作者 ZHENG Shi-Wang Department of Physics and Information Engineering,Shangqiu Teachers College,Shangqiu 476000,ChinaXIE Jia-Fang Department of Mechanics,Beijing Institute of Technology,Beijing 100081,ChinaJIA Li-Qun College of Science,Southern Yangtze University,Wuxi 214122,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期43-47,共5页
Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tz... Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tzénoffequations are given.Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given.Hojman conserved quantity of Tzénoff equations for the system above through special Lie symmetry and Lie symmetryin the condition of special Mei symmetry respectively is obtained. 展开更多
关键词 unilateral constraint Tzénoff equations SYMMETRY Hojman conserved quantity
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A symmetry and a conserved quantity for the Birkhoff system 被引量:12
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作者 梅凤翔 江铁强 解加芳 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1678-1681,共4页
A symmetry and a conserved quantity of the Birkhoff system are studied. The symmetry is called the Birkhoff symmetry. Its definition and criterion are given in this paper. A conserved quantity can be deduced by using ... A symmetry and a conserved quantity of the Birkhoff system are studied. The symmetry is called the Birkhoff symmetry. Its definition and criterion are given in this paper. A conserved quantity can be deduced by using the symmetry. An example is given to illustrate the application of the result. 展开更多
关键词 Birkhoff system SYMMETRY conserved quantity
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Mei symmetry and Mei conserved quantity of nonholonomic systems with unilateral Chetaev type in Nielsen style 被引量:10
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作者 贾利群 解加芳 罗绍凯 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1560-1564,共5页
This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The defini... This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The definition and the criteria of Mei symmetry, loosely Mei symmetry, strictly Mei symmetry for the system are given in this paper. The existence condition and the expression of Mei conserved quantity are deduced directly by using Mei symmetry. An example is given to illustrate the application of the results. 展开更多
关键词 Nielsen style unilateral nonholonomic constrained system Mei symmetry Mei conserved quantity
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A new type of conserved quantity of Mei symmetry for the motion of mechanico electrical coupling dynamical systems 被引量:12
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作者 赵丽 傅景礼 陈本永 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期1-4,共4页
We obtain a new type of conserved quantity of Mei symmetry for the motion of mechanico--electrical coupling dynamical systems under the infinitesimal transformations. A criterion of Mei symmetry for the mechanico-elec... We obtain a new type of conserved quantity of Mei symmetry for the motion of mechanico--electrical coupling dynamical systems under the infinitesimal transformations. A criterion of Mei symmetry for the mechanico-electrical coupling dynamical systems is given. Simultaneously, the condition of existence of the new conserved quantity of Mei symmetry for mechanico-electrical coupling dynamical systems is obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 new conserved quantity Mei symmetry mechanico-electrical coupling systems
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Dissecting conserved cis-regulatory modules of Glu-1 promoters which confer the highly active endosperm-specific expression via stable wheat transformation 被引量:6
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作者 Jihu Li Ke Wang +7 位作者 Genying Li Yulian Li Yong Zhang Zhiyong Liu Xingguo Ye Xianchun Xia Zhonghu He Shuanghe Cao 《The Crop Journal》 SCIE CAS CSCD 2019年第1期8-18,共11页
Wheat high-molecular-weight glutenin subunits(HMW-GS) determine dough elasticity and play an essential role in processing quality. HMW-GS are encoded by Glu-1 genes and controlled primarily at transcriptional level, i... Wheat high-molecular-weight glutenin subunits(HMW-GS) determine dough elasticity and play an essential role in processing quality. HMW-GS are encoded by Glu-1 genes and controlled primarily at transcriptional level, implemented through the interactions between cis-acting elements and trans-acting factors. However, transcriptional mechanism of Glu-1 genes remains elusive. Here we made a comprehensive analysis of cis-regulatory elements within 1-kb upstream of the Glu-1 start codon(-1000 to-1) and identified 30 conserved motifs. Based on motif distribution pattern, three conserved cis-regulatory modules(CCRMs), CCRM1(-300 to-101), CCRM2(-650 to-400), and CCRM3(-950 to-750), were defined, and their functions were characterized in wheat stable transgenic lines transformed with progressive 5′ deletion promoter::GUS fusion constructs. GUS staining, qP CR and enzyme activity assays indicated that CCRM2 and CCRM3 could enhance the expression level of Glu-1, whereas the 300-bp promoter(-300 to-1), spanning CCRM1 and core region(-100 to-1), was enough to ensure accurate Glu-1 initiation at 7 days after flowering(DAF) and shape its spatiotemporal expression pattern during seed development. Further transgenic assays demonstrated that CCRM1-2(-300 to-209) containing Complete HMW Enhancer(-246 to-209) was important for expression level but had no effect on expression specificity in the endosperm. In contrast, CCRM1-1(-208 to-101) was critical for both expression specificity and level of Glu-1. Our findings not only provide new insights to uncover Glu-1 transcription regulatory machinery but also lay foundations for modifying Glu-1 expression. 展开更多
关键词 conserved cis-regulatory modules GLU-1 Transcriptional regulation Transgenic wheat TRITICUM AESTIVUM
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Lie Symmetries and Conserved Quantities of Arbitrary Order Nonholonomic Systems
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作者 赵树信 尚玫 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期131-137,共7页
The invariance of the differential equations under the infinitesimal transformations was used to study the Lie symmetries and conserved quantities of arbitrary order nonholonomic systems. The determining equations, th... The invariance of the differential equations under the infinitesimal transformations was used to study the Lie symmetries and conserved quantities of arbitrary order nonholonomic systems. The determining equations, the restriction equations, the structure equation and the form of the conserved quantities were obtained. 展开更多
关键词 nonholonomic system determining equations restriction equations structure equation conserved quantities
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Conformal invariance and Hojman conserved quantities of first order Lagrange systems 被引量:9
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作者 陈向炜 刘畅 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3180-3184,共5页
In this paper the conformal invariance by infinitesimal transformations of first order Lagrange systems is discussed in detail. The necessary and sufficient conditions of conformal invariance and Lie symmetry simultan... In this paper the conformal invariance by infinitesimal transformations of first order Lagrange systems is discussed in detail. The necessary and sufficient conditions of conformal invariance and Lie symmetry simultaneously by the action of infinitesimal transformations are given. Then it gets the Hojman conserved quantities of conformal invariance by the infinitesimal transformations. Finally an example is given to illustrate the application of the results. 展开更多
关键词 first order Lagrange systems infinitesimal transformation conformal invariance Hojman conserved quantities
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