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Planar cell polarity regulators in asymmetric organogenesis during development and disease

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Journal of Genetics and Genomics 2023年第2期50卷 63-76页

作者： De-li shi Affiliated Hospital of Guangdong Medical University ZhanjiangGuangdong 524001China Laboratory of Developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The phenomenon of planar cell polarity is critically required for a myriad of morphogenetic processes in metazoan and is accurately controlled by several conserved ***“core”proteins,including Friz zled,Flamingo(Celsr),Van Gogh(Vangl),Dishevelled,Prickle,and Diego(Ankrd6),are major components of the Wnt/planar cell polarity *** Fat/Dchs protocadherins and the Scrib polarity complex also function to instruct cellular *** vertebrates,all these pathways are essential for tissue and organ morphogenesis,such as neural tube closure,left-right symmetry breaking,heart and gut morphogenesis,lung and kidney branching,stereociliary bundle orientation,and proximal-distal limb *** in planar polarity genes are closely linked to various congenital *** advances have been made in deciphering their contribution to the establishment of spatially oriented pattern in developing or gans and the maintenance of tissue *** challenge remains to clarify the complex interplay of different polarity pathways in organogenesis and the link of cell polarity to cell fate speciﬁ*** disciplinary approaches are also important to understand the roles of mechanical forces in coupling cellular polarization and *** review outlines current advances on planar polarity regulators in asymmetric organ formation,with the aim to identify questions that deserve further investigation.

关键词： Planar cell polarity Wnt/PCP signaling Left-right asymmetry Heart and gut morphogenesis Lung and kidney branching Inner ear hair cell orientation limb outgrowth

Interplay of RNA-binding proteins controls germ cell development in zebrafish

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Journal of Genetics and Genomics 2024年第9期51卷 889-899页

作者： De-li shi Laboratory of Developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants,called germ plasm,confer germline fate in the early *** studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell ***-binding proteins,acting in concert with other germ plasm components,play essential roles in the organization of the germ plasm and the specification,migration,maintenance,and differentiation of primordial germ *** loss of their functions impairs germ cell formation and causes sterility or sexual *** is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ ***,the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell *** failure to control the developmental outcome of germ cells disrupts the formation of gametes,it is important to gain a complete picture of regulatory mechanisms operating in the germ cell *** review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

关键词： Germplasm Primordialgerm cell Germlinestem cell Gametogenesis Zebrafish RNA-binding protein Posttranscriptional gene expression Translational activation and repression

Parametric approach to track following control of FFSM

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Journal of Systems Engineering and Electronics 2011年第5期22卷 810-815页

作者： shi li Guangren Duan Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 P. R. China

A robust task space tracking scheme is proposed for the free-flying space manipulator system. The dynamic equations of the system are derived via the law of momentum conservation, and then a linear state space representation is formulated by local linearization. A parametric approach is applied by using the eigenstructure assignment theory and the model reference method. A feedback stabilizing controller and a feedforward compensation controller are built based on the approach. Then an optimization procedure is followed after that to obtain the desired requirement and characteristics. Simulation results are presented to show the effectiveness of the proposed method.

关键词： free-flying space manipulator (FFSM) model reference tracking control parametric approach.

On Two Theorems of Finite Solvable Groups

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Acta Mathematica Sinica,English Series 2005年第4期21卷 797-802页

作者： shi Rong li Department of Mathematics Guangxi University Nanning 530004 P. R. China

For a finite group G, let T（G） denote a set of primes such that a prime p belongs to T（G） if and only if p is a divisor of the index of some maximal subgroup of G. It is proved that if G satisfies any one of the following conditions：（1） G has a p-complement for each p∈T（G）; （2）│T（G）│= 2：（3） the normalizer of a Sylow p-subgroup of G has prime power index for each odd prime p∈T（G）; then G either is solvable or G/Sol（G）≌PSL（2, 7） where Sol（G） is the largest solvable normal subgroup of G.

关键词： Finite solvable group The index of a maximal subgroup Simple group

Matrix orthogonal polynomials,non-abelian Toda lattices,and Bäcklund transformations

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Science China Mathematics 2024年第9期67卷 2071-2090页

作者： shi-Hao li Department of Mathematics Sichuan UniversityChengdu 610064China

A connection between matrix orthogonal polynomials and non-abelian integrable lattices is investigated in this *** normalization factors of matrix orthogonal polynomials expressed using quasideterminants are shown to be the solutions to the non-abelian Toda lattice in semi-discrete and full-discrete ***,with a moment modification method,we demonstrate that the B¨acklund transformation of the non-abelian Toda lattice given by Popowicz(1983)is equivalent to the non-abelian Volterra lattice,whose solutions can be expressed using quasi-determinants as well.

关键词： matrix orthogonal polynomial non-abelian Toda lattice Backlund transformation quasideterminant technique

On s-Quasinormal and c-Normal Subgroups of a Finite Group

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Acta Mathematica Sinica,English Series 2008年第4期24卷 647-654页

作者： shi Rong li Department of Mathematics Guangxi University Nanning Guangxi 530004 P. R. China

Let F be a saturated formation containing the class of supersolvable groups and let G be a finite group. The following theorems are shown：（1） G ∈ F if and only if there is a normal subgroup H such that G/H ∈ F and every maximal subgroup of all Sylow subgroups of H is either c-normal or s-quasinormally embedded in G; （2） G ∈F if and only if there is a soluble normal subgroup H such that G/H∈F and every maximal subgroup of all Sylow subgroups of F（H）, the Fitting subgroup of H, is either e-normally or s-quasinormally embedded in G.

关键词： s-quasinormally embedded subgroup c-normal subgroup p-nilpotent group saturated formation

Dielectronic Recombination for the Self-Consistent-Field Average Ions

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Chinese Physics Letters 1996年第9期13卷 664-667页

作者： ZHAO li-bo li shi-chang Institute of Applied Physics and Computational Mathematics Beijing 100088

A self-consistent-field theoretical method has been developed to treat the dielectronic recombination(DR)of average ions with *** on the method,the rate coefficients for DR into a special state can be *** an example,t... 详细信息

关键词： population method presented

Valence electron structure and hydrogen storage property of LaNi_-4Co

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Rare Metals 2015年第4期34卷 259-266页

作者： Lei Zhang shi-Chun li School of Electromechanical Automobile Engineering Yantai University Key Laboratory of Advanced Manufacturing and Control Technology in Universities of Shandong Materials Department College of Electromechanical Engineering China University of Petroleum

In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures （VESs） of these two models were investigated according to empirical electron theory （EET） of solids and molecules. Results demonstrate that the VES-concerned hardness factor （FH） of LaNi4Co is lower than that of LaNi5, so LaNi4Co has lower hardness, higher plasticity and improved anti-pulverization ability. In the mean time, the difference of the equilibrium hydrogen pressure between LaNiaCo and LaNi5 was analyzed in the electronic level. The analysis shows that the strength of the weakest bond net in octahedron lattice interstices of LaNi4Co is much lower than that in LaNis; consequently, LaNi4Co＇s bond net easily deforms to accommodate hydrogen so that LaNi4Co has lower equilibrium hydrogen pressure in comparison with LaNis. The results can provide some theory guide on the design of hydrogen storage alloys.

关键词： Alloys Computer modeling and simulation Electronic structure Mechanical properties

Fully Nonlinear Time Domain Analysis for Hydrodynamic Performance of An Oscillating Wave Surge Converter

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China Ocean Engineering 2018年第5期32卷 582-592页

作者： SUN shi-yan SUN shi-li WU Guo-xiong School of Naval Architecture & Ocean Engineering Jiangsu University of Science and Technology College of shipbuilding Engineering Harbin Engineering University Department of Mechanical Engineering University College London

The hydrodynamic behaviour of an oscillating wave surge converter(OWSC) in large motion excited by nonlinear waves is investigated. The mechanism through which the wave energy is absorbed in the nonlinear system is analysed. The mathematical model used is based on the velocity potential theory together with the fully nonlinear boundary conditions on the moving body surface and deforming free surface. The problem is solved by the boundary element method. Numerical results are obtained to show how to adjust the mechanical properties of the OWSC to achieve the best efficiency in a given wave, together with the nonlinear effect of the wave height. Numerical results are also provided to show the behaviour of a given OWSC in waves of different frequencies and different heights.

关键词： wave energy oscillating wave surge converter nonlinear wave/structure interactions boundary element method