Ligularia jaluensis is an important medicinal and ornamental plant in China.However,the viruses capable of infecting Ligularia jaluensis remains unknown.Here,we identified a novel carlavirus,tentatively named ligulari...Ligularia jaluensis is an important medicinal and ornamental plant in China.However,the viruses capable of infecting Ligularia jaluensis remains unknown.Here,we identified a novel carlavirus,tentatively named ligularia jaluensis carlavirus(LJCV),as well as a known iris severe mosaic virus(ISMV),in L.jaluensis plants displaying chlorosis and yellow ring spot symptoms,using RNA-seq analysis.The LJCV genome consists of an 8497 nt positive-sense,single-stranded RNA[excluding the poly(A)tail],and contains six open reading frames(ORFs).Phylogenetic analyses based on the fulllength genome and RNA-dependent RNA polymerase(RdRp)amino acid(aa)sequences revealed that LJCV clusters within an evolutionary branch alongside known viruses in the Carlavirus genus.The RdRp protein encoded by ORF1 of LJCV shared 45.38%–67.41%identity with the corresponding proteins of eight closely related carlaviruses.ORFs 2–4 constitute the triple gene block(TGB),with TGBp1 and TGBp3 localized in the endoplasmic reticulum(ER),while TGBp2 is localized at plasmodesmata(PD)and facilitates viral intercellular movement,as demonstrated by its ability to complement the potato virus X with movement-deficient mutant(PVX-Δp25-GFP).Additionally,ORF6 encodes a cysteine-rich protein(CRP)that is localized in the chloroplast and functions as a viral pathogenicity factor,inducing severe viral symptoms in the heterologous PVX expression system.Furthermore,we successfully constructed an infectious cDNA clone of LJCV,and found that it can infect Nicotiana benthamiana plants through mechanical inoculation or agrobacterium-mediated infiltration of the LJCV infectious clone.These findings enhance our understanding of the characteristics and host range of carlaviruses,as well as the viruses capable of infecting L.jaluensis.展开更多
A shell whose height is far less than the minimum size covering the bottom is called the shallow shell.As a branch of linear elastic shell,it is a special shell with large span and has been widely applied in engineeri...A shell whose height is far less than the minimum size covering the bottom is called the shallow shell.As a branch of linear elastic shell,it is a special shell with large span and has been widely applied in engineering fields.The main aim of this paper is to construct a general nonconforming finite element framework for a two-dimensional shallow shell model proposed by Ciarlet and Miara.Based on the different regularities of the displacement components,we give the special properties satisfied by the general framework and provide several nonconforming finite element discretization schemes.Then,the existence and uniqueness of the numerical solutions are proved,with the rate of convergence derived.Finally,numerical experiments are carried out for the paraboloid,spherical dome and cylindrical bridge,which validates the theoretical analyses.Moreover,the computing cost of discretizing the shallow shell model is evidently less than that of discretizing the general shell model with comparable accuracy when the shell is the large span shell.展开更多
基金financially supported by the Hainan Province Science and Technology Special Fund(No.ZDYF2022XDNY240)the National Key Research and Development Program of China(2022YFD1401200).
文摘Ligularia jaluensis is an important medicinal and ornamental plant in China.However,the viruses capable of infecting Ligularia jaluensis remains unknown.Here,we identified a novel carlavirus,tentatively named ligularia jaluensis carlavirus(LJCV),as well as a known iris severe mosaic virus(ISMV),in L.jaluensis plants displaying chlorosis and yellow ring spot symptoms,using RNA-seq analysis.The LJCV genome consists of an 8497 nt positive-sense,single-stranded RNA[excluding the poly(A)tail],and contains six open reading frames(ORFs).Phylogenetic analyses based on the fulllength genome and RNA-dependent RNA polymerase(RdRp)amino acid(aa)sequences revealed that LJCV clusters within an evolutionary branch alongside known viruses in the Carlavirus genus.The RdRp protein encoded by ORF1 of LJCV shared 45.38%–67.41%identity with the corresponding proteins of eight closely related carlaviruses.ORFs 2–4 constitute the triple gene block(TGB),with TGBp1 and TGBp3 localized in the endoplasmic reticulum(ER),while TGBp2 is localized at plasmodesmata(PD)and facilitates viral intercellular movement,as demonstrated by its ability to complement the potato virus X with movement-deficient mutant(PVX-Δp25-GFP).Additionally,ORF6 encodes a cysteine-rich protein(CRP)that is localized in the chloroplast and functions as a viral pathogenicity factor,inducing severe viral symptoms in the heterologous PVX expression system.Furthermore,we successfully constructed an infectious cDNA clone of LJCV,and found that it can infect Nicotiana benthamiana plants through mechanical inoculation or agrobacterium-mediated infiltration of the LJCV infectious clone.These findings enhance our understanding of the characteristics and host range of carlaviruses,as well as the viruses capable of infecting L.jaluensis.
基金supported by the National Natural Science Foundation of China(NSFC Nos.11971379 and 12071443)the Distinguished Youth Foundation of Shaanxi Province(2022JC-01).
文摘A shell whose height is far less than the minimum size covering the bottom is called the shallow shell.As a branch of linear elastic shell,it is a special shell with large span and has been widely applied in engineering fields.The main aim of this paper is to construct a general nonconforming finite element framework for a two-dimensional shallow shell model proposed by Ciarlet and Miara.Based on the different regularities of the displacement components,we give the special properties satisfied by the general framework and provide several nonconforming finite element discretization schemes.Then,the existence and uniqueness of the numerical solutions are proved,with the rate of convergence derived.Finally,numerical experiments are carried out for the paraboloid,spherical dome and cylindrical bridge,which validates the theoretical analyses.Moreover,the computing cost of discretizing the shallow shell model is evidently less than that of discretizing the general shell model with comparable accuracy when the shell is the large span shell.
