Unveiling the molecular mechanisms underlying rotavirus replication and pathogenesis has been hampered by the lack of a reverse genetics(RG)system in the past.Since 2017,multiple plasmid-based RG systems for simian,hu...Unveiling the molecular mechanisms underlying rotavirus replication and pathogenesis has been hampered by the lack of a reverse genetics(RG)system in the past.Since 2017,multiple plasmid-based RG systems for simian,human,and murine-like rotaviruses have been established.However,none of the described methods have supported the recovery of bovine rotaviruses(BRVs).Here,we established an optimized plasmid-based RG system for BRV culture-adapted strain(BRV G10P[15]BLR)and clinical isolates(BRV G6P[1]C73,G10P[11]HM26)based on a BHK-T7 cell clone stably expressing T7 polymerase.Furthermore,using this optimized RG system,we successfully rescued the reporter virus BRV rC73/Zs,rHM26/Zs and rBLR/Zs,harboring a genetically modified 1.8-kb segment 7 encoding full-length nonstructural protein 3(NSP3)fused to ZsGreen,a 232-amino acid green fluorescent protein.Analysis of the stability of genomic insertions showed that the rC73/Zs and rBLR/Zs replicated efficiently and were genetically stable in seven rounds of serial passaging,while rHM26/Zs can be stabilized only up to the third generation,indicating that the BRV segment composition may influence the viral fitness.In addition,we adopted the recombinant reporter viruses for high-throughput screening application and discovered 12 candidates out of 1440 compounds with potential antiviral activities against rotavirus.In summary,this improved RG system of BRVs represents an important tool with great potential for understanding the molecular biology of BRV and facilitates the development of novel therapeutics and vaccines for BRV.展开更多
To solve the problems of low efficiency and multi-solvability of humanoid manipulator Cartesian space path planning in physical human-robot interaction,an improved bi-directional rapidly-exploring random tree algorith...To solve the problems of low efficiency and multi-solvability of humanoid manipulator Cartesian space path planning in physical human-robot interaction,an improved bi-directional rapidly-exploring random tree algorithm based on greedy growth strategy in 3D space is proposed.The workspace of manipulator established based on Monte Carlo method is used as the sampling space of the rapidly-exploring random tree,and the opposite expanding greedy growth strategy is added in the random tree expansion process to improve the path planning efficiency.Then the generated path is reversely optimized to shorten the length of the planned path,and the optimized path is interpolated and pose searched in Cartesian space to form a collision-free optimized path suitable for humanoid manipulator motion.Finally,the validity and reliability of the algorithm are verified in an intelligent elderly care service scenario based on Walker2,a large humanoid service robot.展开更多
The mass entransy describes the mass-diffusion ability of the solution system, and the mass-diffusion process with the finite concentration difference always leads to the mass-entransy dissipation. This paper studies ...The mass entransy describes the mass-diffusion ability of the solution system, and the mass-diffusion process with the finite concentration difference always leads to the mass-entransy dissipation. This paper studies the equimolar reverse constant-temperature mass-diffusion process with Fick's law( g∝Δ(c)). The optimal concentration paths for the MED(Minimum Entransy Dissipation) are derived and compared with those for the MEG(Minimum Entropy Generation) and CCR(Constant Concentration Ratio) operations. It is indicated that the strategy of the MED is equivalent to that of the CCD(Constant Concentration Difference) of the same component; whether the MED or the MEG is selected as the optimization objective, the strategy of the CCD is much better than that of the CCR.展开更多
This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle graphs.Given a‘selective’subset of the vertices of the underlying cycle graph as location of the existin...This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle graphs.Given a‘selective’subset of the vertices of the underlying cycle graph as location of the existing customers,the task is to modify the edge lengths within a given budget such that the minimum of distances between a predetermined undesirable facility location and the customer points is maximized under the perturbed edge lengths.We develop a combinatorial O(n log n)algorithm for the problem with continuous modifications.For the uniform-cost model,we solve this problem in linear time by an improved algorithm.Furthermore,exact solution methods are proposed for the problem with integer modifications.展开更多
基金supported by the Heilongjiang Provincial Natural Science Foundation of China(grant no.LH2033C107)the National Key Research and Development Program of China(2023YFD1801302)the Central Public-interest Scientific Institution Basal Research Fund(grant no.1610302022010).
文摘Unveiling the molecular mechanisms underlying rotavirus replication and pathogenesis has been hampered by the lack of a reverse genetics(RG)system in the past.Since 2017,multiple plasmid-based RG systems for simian,human,and murine-like rotaviruses have been established.However,none of the described methods have supported the recovery of bovine rotaviruses(BRVs).Here,we established an optimized plasmid-based RG system for BRV culture-adapted strain(BRV G10P[15]BLR)and clinical isolates(BRV G6P[1]C73,G10P[11]HM26)based on a BHK-T7 cell clone stably expressing T7 polymerase.Furthermore,using this optimized RG system,we successfully rescued the reporter virus BRV rC73/Zs,rHM26/Zs and rBLR/Zs,harboring a genetically modified 1.8-kb segment 7 encoding full-length nonstructural protein 3(NSP3)fused to ZsGreen,a 232-amino acid green fluorescent protein.Analysis of the stability of genomic insertions showed that the rC73/Zs and rBLR/Zs replicated efficiently and were genetically stable in seven rounds of serial passaging,while rHM26/Zs can be stabilized only up to the third generation,indicating that the BRV segment composition may influence the viral fitness.In addition,we adopted the recombinant reporter viruses for high-throughput screening application and discovered 12 candidates out of 1440 compounds with potential antiviral activities against rotavirus.In summary,this improved RG system of BRVs represents an important tool with great potential for understanding the molecular biology of BRV and facilitates the development of novel therapeutics and vaccines for BRV.
基金The Key-Area Research and Development Program of Guangdong Province,China(No.2019B010154003)。
文摘To solve the problems of low efficiency and multi-solvability of humanoid manipulator Cartesian space path planning in physical human-robot interaction,an improved bi-directional rapidly-exploring random tree algorithm based on greedy growth strategy in 3D space is proposed.The workspace of manipulator established based on Monte Carlo method is used as the sampling space of the rapidly-exploring random tree,and the opposite expanding greedy growth strategy is added in the random tree expansion process to improve the path planning efficiency.Then the generated path is reversely optimized to shorten the length of the planned path,and the optimized path is interpolated and pose searched in Cartesian space to form a collision-free optimized path suitable for humanoid manipulator motion.Finally,the validity and reliability of the algorithm are verified in an intelligent elderly care service scenario based on Walker2,a large humanoid service robot.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51576207 & 51356001)
文摘The mass entransy describes the mass-diffusion ability of the solution system, and the mass-diffusion process with the finite concentration difference always leads to the mass-entransy dissipation. This paper studies the equimolar reverse constant-temperature mass-diffusion process with Fick's law( g∝Δ(c)). The optimal concentration paths for the MED(Minimum Entransy Dissipation) are derived and compared with those for the MEG(Minimum Entropy Generation) and CCR(Constant Concentration Ratio) operations. It is indicated that the strategy of the MED is equivalent to that of the CCD(Constant Concentration Difference) of the same component; whether the MED or the MEG is selected as the optimization objective, the strategy of the CCD is much better than that of the CCR.
基金the Sahand University of Technology under the Ph.D.program contract(No.30/15971).
文摘This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle graphs.Given a‘selective’subset of the vertices of the underlying cycle graph as location of the existing customers,the task is to modify the edge lengths within a given budget such that the minimum of distances between a predetermined undesirable facility location and the customer points is maximized under the perturbed edge lengths.We develop a combinatorial O(n log n)algorithm for the problem with continuous modifications.For the uniform-cost model,we solve this problem in linear time by an improved algorithm.Furthermore,exact solution methods are proposed for the problem with integer modifications.
