Information diffusion on social media has become a key strategy in people’s daily interactions. This paper studies consumers’ participation in the product information diffusion, and analyzes the complexity of inform...Information diffusion on social media has become a key strategy in people’s daily interactions. This paper studies consumers’ participation in the product information diffusion, and analyzes the complexity of information diffusion which is affected by many factors. Prior investigations of information diffusion have primarily focused on the composition of diffusion networks with independent factors and the intricacy of the process has not been completely evaluated. The majority of prior investigations have focused on strategies and the moving forces in social media processes and the determination of influential seed nodes, with few evaluations conducted about the factors affecting consumers’ choices in information diffusion. In this study, a Bayesian network model of product information diffusion was created to examine the links between factors and consumer deportment. It revealed how those factors had an impact on each other and on consumer deportment choice. The innovation of the thesis is reflected in the exploration and analysis of the specific communication path of product information diffusion, which provides a better marketing idea and practical method for the development of mobile e-commerce. The research findings can help identify the quantitative relationships between the factors affecting the process of product information diffusion and user behavior.展开更多
Female-to-male sex reversals(pseudomales)are common in lower vertebrates and have been found in natural populations,which is a concern under rapid changes in environmental conditions.Pseudomales can exhibit altered sp...Female-to-male sex reversals(pseudomales)are common in lower vertebrates and have been found in natural populations,which is a concern under rapid changes in environmental conditions.Pseudomales can exhibit altered spermatogenesis.However,the regulatory mechanisms underlying pseudomale spermatogenesis remain unclear.Here,we characterized spermatogenesis in Chinese tongue sole(Cynoglossus semilaevis),a species with genetic and environmental sex determination,based on a highresolution single-cell RNA-seq atlas of cells derived from the testes of genotypic males and pseudomales.We identified five germ cell types and six somatic cell types and obtained a single-cell atlas of dynamic changes in gene expression during spermatogenesis in Chinese tongue sole,including alterations in pseudomales.We detected decreased levels of Ca^(2+)signaling pathway-related genes in spermatogonia,insufficient meiotic initiation in spermatocytes,and a malfunction of somatic niche cells in pseudomales.However,a cluster of CaSR genes and MAPK signaling factors were upregulated in undifferentiated spermatogonia of pseudomales.Additionally,we revealed that Z chromosome-specific genes,such as piwil2,dhx37,and ehmt1,were important for spermatogenesis.These results improve our understanding of reproduction after female-to-male sex-reversal and provide new insights into the adaptability of reproductive strategies in lower vertebrates.展开更多
An explicit Bargmann symmetry constraint is computed and its associated binary nonlinearization of Lax pairs is carried out for the super Dirac systems. Under the obtained symmetry constraint, the n-th flow of the sup...An explicit Bargmann symmetry constraint is computed and its associated binary nonlinearization of Lax pairs is carried out for the super Dirac systems. Under the obtained symmetry constraint, the n-th flow of the super Dirac hierarchy is decomposed into two super finite-dimensional integrable Hamiltonian systems, defined over the super-symmetry manifold R4N|2N with the corresponding dynamical variables x and tn. The integrals of motion required for Liouville integrability are explicitly given.展开更多
Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herei...Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herein,with D_(2)O as the D source,we first propose an electrocatalytic deuteration strategy for continuous production of deuterated ethylene from acetylene under ambient conditions.Specially,Ag nanoparticles exhibit a very high deuterated ethylene Faradic efficiency of up to 99.3%at-0.6 V vs.reversible hydrogen electrode.Meanwhile,Ag nanoparticles achieve a deuterated ethylene production rate of 3.72×10^(3)mmol h^(-1)g^(-1)cat and an excellent long-term stability with deuterated ethylene Faradaic efficiencies of~95%in a two-electrode flow cell,which substantially outperform state-of-the-art values for previously reported deuterated alkenes.In-situ electrochemical Infrared absorption and Raman spectroscopies reveal superior acetylene absorption and formation of deuterated ethylene on Ag nanoparticles.This efficient electrocatalytic deuteration strategy opens a new window for continuous and economic production of deuterated alkenes.展开更多
Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter gene...Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter genes,which function in conferring disease susceptibility(S)in rice plants.To engineer broadspectrum bacterial blight resistance,we used CRISPR/Cas9-mediated gene editing to disrupt the TALEbinding elements(EBEs)of two S genes,OsSWEETH and OsSWEET14,in rice cv.Kitaake,which harbors the recessive resistance allele of Xa25/OsSWEET13.The engineered rice line MS14K exhibited broadspectrum resistance to most Xoo strains with a few exceptions,suggesting that the compatible strains may contain new TALEs.We identified two PthXo2-like TALEs,Tal5LN18 and Tal7PX061,as major virulence factors in the compatible Xoo strains LN18 and PX061,respectively,and found that Xoo encodes at least five types of PthXo2-like effectors.Given that PthXo2/PthXo2.1 target OsSlVEETf3 for transcriptional activation,the genomes of 3000 rice varieties were analyzed for EBE variationsin the OsSWEET13 promoter,and 10Xa25-like haplotypes were identified.We found that Tal5LN18 and Tal7PX〇6i bind slightly different EBE sequences in the OsSWEET13 promoter to activate its expression.CRISPR/Cas9 technology was then used to generate InDels in the EBE of the OsSWEET13 promoter in MS14K to creat a new germplasm with three edited OsSWEET EBEs and broad-spectrum resistance against all Xoo strains tested.Collectively,our findings illustrate how to disarm TALE-S co-evolved loci to generate broad-spectrum resistance through the loss of effector-triggered susceptibility in plants.展开更多
A class of non-semisimple matrix loop algebras consisting of triangular block matrices is introduced and used to generate bi-integrable couplings of soliton equations from zero curvature equations.The variational iden...A class of non-semisimple matrix loop algebras consisting of triangular block matrices is introduced and used to generate bi-integrable couplings of soliton equations from zero curvature equations.The variational identities under non-degenerate,symmetric and ad-invariant bilinear forms are used to furnish Hamiltonian structures of the resulting bi-integrable couplings.A special case of the suggested loop algebras yields nonlinear bi-integrable Hamiltonian couplings for the AKNS soliton hierarchy.展开更多
Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial leaf blight in rice,delivers transcription activator-like effector(TALE)proteins into host cells to activate susceptibility or resistance(R)genes that pr...Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial leaf blight in rice,delivers transcription activator-like effector(TALE)proteins into host cells to activate susceptibility or resistance(R)genes that promote disease or immunity,respectively.Nonhost plants serve as potential reservoirs of R genes;consequently,nonhost R genes may trap TALEs to trigger an immune response.In this study,we screened 17 Xoo TALEs for their ability to induce a hypersensitive response(HR)in the nonhost plant Nicotiana benthamiana(Nb);only AvrXa10 elicited an HR when transiently expressed in Nb.The HR generated by AvrXa10 required both the central repeat region and the activation domain,suggesting a specific interaction between AvrXa10 and a potential R-like gene in nonhost plants.Evans blue staining and ion leakage measurements confirmed that the AvrXa10-triggered HR was a form of cell death,and the transient expression of AvrXa10 in Nb induced immune responses.Genes targeted by AvrXa10 in the Nb genome were identified by transcriptome profiling and prediction of effector binding sites.Using several approaches(in vivo reporter assays,electrophoretic mobility-shift assays,targeted designer TALEs,and on-spot gene silencing),we confirmed that AvrXa10 targets NbZnFP1,a C2H2-type zinc finger protein that resides in the nucleus.Functional analysis indicated that overexpression of NbZnFP1 and its rice orthologs triggered cell death in rice protoplasts.An NbZnFP1 ortholog was also identified in tomato and was specifically activated by AvrXa10.These results demonstrate that NbZnFP1 is a nonhost R gene that traps AvrXa10 to promote plant immunity in Nb.展开更多
Background:RNA secondary structures play a pivotal role in posttranscriptional regulation and the functions of non-coding RNAs,yet in vivo RNA secondary structures remain enigmatic.PARIS(Psoralen Analysis of RNA Inter...Background:RNA secondary structures play a pivotal role in posttranscriptional regulation and the functions of non-coding RNAs,yet in vivo RNA secondary structures remain enigmatic.PARIS(Psoralen Analysis of RNA Interactions and Structures)is a recently developed high-throughput sequencing-based approach that enables direct capture of RNA duplex structures in vivo.However,the existence of incompatible,fuzzy pairing information obstructs the integration of PARIS data with the existing tools for reconstructing RNA secondary structure models at the single-base resolution.Methods:We introduce IRIS,a method for predicting RNA secondary structure ensembles based on PARIS data.IRIS generates a large set of candidate RNA secondary structure models under the guidance of redistributed PARIS reads and then uses a Bayesian model to identify the optimal ensemble,according to both thermodynamic principles and PARIS data.Results:The predicted RNA structure ensembles by IRIS have been verified based on evolutionary conservation information and consistency with other experimental RNA structural data.HIS is implemented in Python and freely available at http://iris.zhanglab.net.Conclusion:IRIS capitalizes upon PARIS data to improve the prediction of in vivo RNA secondary structure ensembles.We expect that IRIS will enhance the application of the PARIS technology and shed more insight on in vivo RNA secondary structures.展开更多
文摘Information diffusion on social media has become a key strategy in people’s daily interactions. This paper studies consumers’ participation in the product information diffusion, and analyzes the complexity of information diffusion which is affected by many factors. Prior investigations of information diffusion have primarily focused on the composition of diffusion networks with independent factors and the intricacy of the process has not been completely evaluated. The majority of prior investigations have focused on strategies and the moving forces in social media processes and the determination of influential seed nodes, with few evaluations conducted about the factors affecting consumers’ choices in information diffusion. In this study, a Bayesian network model of product information diffusion was created to examine the links between factors and consumer deportment. It revealed how those factors had an impact on each other and on consumer deportment choice. The innovation of the thesis is reflected in the exploration and analysis of the specific communication path of product information diffusion, which provides a better marketing idea and practical method for the development of mobile e-commerce. The research findings can help identify the quantitative relationships between the factors affecting the process of product information diffusion and user behavior.
基金supported by the National Key R&D Program of China(2018YFD0900301)the National Nature Science Foundation of China(31722058,31802275,31472269)+4 种基金the AoShan Talents Cultivation Program Supported by Qingdao National Laboratory for Marine Science and Technology(2017ASTCP-ES06)the Taishan Scholar Project Fund of Shandong of China to C.S.the National Ten-Thousands Talents Special Support Program to C.S.the Central Public-interest Scientific Institution Basal Research Fund,CAFS(2020TD19)the China Agriculture Research System(CARS-47-G03)。
文摘Female-to-male sex reversals(pseudomales)are common in lower vertebrates and have been found in natural populations,which is a concern under rapid changes in environmental conditions.Pseudomales can exhibit altered spermatogenesis.However,the regulatory mechanisms underlying pseudomale spermatogenesis remain unclear.Here,we characterized spermatogenesis in Chinese tongue sole(Cynoglossus semilaevis),a species with genetic and environmental sex determination,based on a highresolution single-cell RNA-seq atlas of cells derived from the testes of genotypic males and pseudomales.We identified five germ cell types and six somatic cell types and obtained a single-cell atlas of dynamic changes in gene expression during spermatogenesis in Chinese tongue sole,including alterations in pseudomales.We detected decreased levels of Ca^(2+)signaling pathway-related genes in spermatogonia,insufficient meiotic initiation in spermatocytes,and a malfunction of somatic niche cells in pseudomales.However,a cluster of CaSR genes and MAPK signaling factors were upregulated in undifferentiated spermatogonia of pseudomales.Additionally,we revealed that Z chromosome-specific genes,such as piwil2,dhx37,and ehmt1,were important for spermatogenesis.These results improve our understanding of reproduction after female-to-male sex-reversal and provide new insights into the adaptability of reproductive strategies in lower vertebrates.
基金Project supported by the Hangdian Foundation (No. KYS075608072)the National Natural Science Foundation of China (Nos. 10671187, 10971109)the Program for New Century Excellent Talents in University of China (No. NCET-08-0515)
文摘An explicit Bargmann symmetry constraint is computed and its associated binary nonlinearization of Lax pairs is carried out for the super Dirac systems. Under the obtained symmetry constraint, the n-th flow of the super Dirac hierarchy is decomposed into two super finite-dimensional integrable Hamiltonian systems, defined over the super-symmetry manifold R4N|2N with the corresponding dynamical variables x and tn. The integrals of motion required for Liouville integrability are explicitly given.
基金supported by the Natural Science Foundation of Shaanxi Province(No.2020JQ-141)the National Natural Science Foundation of China(No.22005245)+1 种基金the Synergy Innovation Foundation of the University and Enterprise for Graduate Students in Northwestern Polytechnical University(No.CX2021037)the National Key Research and Development Program of China(No.SQ2021YFE010191)。
文摘Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herein,with D_(2)O as the D source,we first propose an electrocatalytic deuteration strategy for continuous production of deuterated ethylene from acetylene under ambient conditions.Specially,Ag nanoparticles exhibit a very high deuterated ethylene Faradic efficiency of up to 99.3%at-0.6 V vs.reversible hydrogen electrode.Meanwhile,Ag nanoparticles achieve a deuterated ethylene production rate of 3.72×10^(3)mmol h^(-1)g^(-1)cat and an excellent long-term stability with deuterated ethylene Faradaic efficiencies of~95%in a two-electrode flow cell,which substantially outperform state-of-the-art values for previously reported deuterated alkenes.In-situ electrochemical Infrared absorption and Raman spectroscopies reveal superior acetylene absorption and formation of deuterated ethylene on Ag nanoparticles.This efficient electrocatalytic deuteration strategy opens a new window for continuous and economic production of deuterated alkenes.
基金This research was supported by the National Key Research and Development Program of China(2016YFD0100601)the National Natural Science Foundation of China(31830072)the National Transgenic Major Program(2016ZX08001-002).
文摘Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter genes,which function in conferring disease susceptibility(S)in rice plants.To engineer broadspectrum bacterial blight resistance,we used CRISPR/Cas9-mediated gene editing to disrupt the TALEbinding elements(EBEs)of two S genes,OsSWEETH and OsSWEET14,in rice cv.Kitaake,which harbors the recessive resistance allele of Xa25/OsSWEET13.The engineered rice line MS14K exhibited broadspectrum resistance to most Xoo strains with a few exceptions,suggesting that the compatible strains may contain new TALEs.We identified two PthXo2-like TALEs,Tal5LN18 and Tal7PX061,as major virulence factors in the compatible Xoo strains LN18 and PX061,respectively,and found that Xoo encodes at least five types of PthXo2-like effectors.Given that PthXo2/PthXo2.1 target OsSlVEETf3 for transcriptional activation,the genomes of 3000 rice varieties were analyzed for EBE variationsin the OsSWEET13 promoter,and 10Xa25-like haplotypes were identified.We found that Tal5LN18 and Tal7PX〇6i bind slightly different EBE sequences in the OsSWEET13 promoter to activate its expression.CRISPR/Cas9 technology was then used to generate InDels in the EBE of the OsSWEET13 promoter in MS14K to creat a new germplasm with three edited OsSWEET EBEs and broad-spectrum resistance against all Xoo strains tested.Collectively,our findings illustrate how to disarm TALE-S co-evolved loci to generate broad-spectrum resistance through the loss of effector-triggered susceptibility in plants.
基金Project supported by the State Administration of Foreign Experts Affairs of Chinathe National Natural Science Foundation of China (Nos.10971136,10831003,61072147,11071159)+3 种基金the Chunhui Plan of the Ministry of Education of Chinathe Innovation Project of Zhejiang Province (No.T200905)the Natural Science Foundation of Shanghai (No.09ZR1410800)the Shanghai Leading Academic Discipline Project (No.J50101)
文摘A class of non-semisimple matrix loop algebras consisting of triangular block matrices is introduced and used to generate bi-integrable couplings of soliton equations from zero curvature equations.The variational identities under non-degenerate,symmetric and ad-invariant bilinear forms are used to furnish Hamiltonian structures of the resulting bi-integrable couplings.A special case of the suggested loop algebras yields nonlinear bi-integrable Hamiltonian couplings for the AKNS soliton hierarchy.
基金This work was supported by the National Natural Science Foundation of China(31830072)the National Key Research and Development Program of China(2016YFD0100601)the National Transgenic Major Program(2016ZX08001-002).
文摘Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial leaf blight in rice,delivers transcription activator-like effector(TALE)proteins into host cells to activate susceptibility or resistance(R)genes that promote disease or immunity,respectively.Nonhost plants serve as potential reservoirs of R genes;consequently,nonhost R genes may trap TALEs to trigger an immune response.In this study,we screened 17 Xoo TALEs for their ability to induce a hypersensitive response(HR)in the nonhost plant Nicotiana benthamiana(Nb);only AvrXa10 elicited an HR when transiently expressed in Nb.The HR generated by AvrXa10 required both the central repeat region and the activation domain,suggesting a specific interaction between AvrXa10 and a potential R-like gene in nonhost plants.Evans blue staining and ion leakage measurements confirmed that the AvrXa10-triggered HR was a form of cell death,and the transient expression of AvrXa10 in Nb induced immune responses.Genes targeted by AvrXa10 in the Nb genome were identified by transcriptome profiling and prediction of effector binding sites.Using several approaches(in vivo reporter assays,electrophoretic mobility-shift assays,targeted designer TALEs,and on-spot gene silencing),we confirmed that AvrXa10 targets NbZnFP1,a C2H2-type zinc finger protein that resides in the nucleus.Functional analysis indicated that overexpression of NbZnFP1 and its rice orthologs triggered cell death in rice protoplasts.An NbZnFP1 ortholog was also identified in tomato and was specifically activated by AvrXa10.These results demonstrate that NbZnFP1 is a nonhost R gene that traps AvrXa10 to promote plant immunity in Nb.
基金the Chinese Ministry of Science and Technology(No.2018YFA0107603 to Q.C.Z.)the National Natural Science Foundation ofChina(Nos.91740204 and 31761163007 to Q.C.Z.)+1 种基金the National Natural Science Foundation of China(No.61772197 to T.J.)the National Key Research and Development Program of China(No.2018YFC0910404 to T.J.)。
文摘Background:RNA secondary structures play a pivotal role in posttranscriptional regulation and the functions of non-coding RNAs,yet in vivo RNA secondary structures remain enigmatic.PARIS(Psoralen Analysis of RNA Interactions and Structures)is a recently developed high-throughput sequencing-based approach that enables direct capture of RNA duplex structures in vivo.However,the existence of incompatible,fuzzy pairing information obstructs the integration of PARIS data with the existing tools for reconstructing RNA secondary structure models at the single-base resolution.Methods:We introduce IRIS,a method for predicting RNA secondary structure ensembles based on PARIS data.IRIS generates a large set of candidate RNA secondary structure models under the guidance of redistributed PARIS reads and then uses a Bayesian model to identify the optimal ensemble,according to both thermodynamic principles and PARIS data.Results:The predicted RNA structure ensembles by IRIS have been verified based on evolutionary conservation information and consistency with other experimental RNA structural data.HIS is implemented in Python and freely available at http://iris.zhanglab.net.Conclusion:IRIS capitalizes upon PARIS data to improve the prediction of in vivo RNA secondary structure ensembles.We expect that IRIS will enhance the application of the PARIS technology and shed more insight on in vivo RNA secondary structures.