Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is proposed.First,the known flow fie...Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is proposed.First,the known flow field data is used to initialize the model parameters,so that the parameters to be trained are close to the optimal value.Then physical prior knowledge is introduced into the training process so that the prediction results not only meet the known flow field information but also meet the physical conservation laws.Through two examples,it is proved that the model under the fusion driven framework can solve the strongly nonlinear flow field problems,and has stronger generalization and expansion.The proposed model is used to solve a muzzle flow field,and the safety clearance behind the barrel side is divided.It is pointed out that the shape of the safety clearance under different launch speeds is roughly the same,and the pressure disturbance in the area within 9.2 m behind the muzzle section exceeds the safety threshold,which is a dangerous area.Comparison with the CFD results shows that the calculation efficiency of the proposed model is greatly improved under the condition of the same calculation accuracy.The proposed model can quickly and accurately simulate the muzzle flow field under various launch conditions.展开更多
Overuse of fungicides and fertilizers has resulted in copper(Cu)contamination of soils and toxic levels of Cu in apple fruits.To breed Cu-resistant apple(Malus domestica)cultivars,the underlying molecular mechanisms a...Overuse of fungicides and fertilizers has resulted in copper(Cu)contamination of soils and toxic levels of Cu in apple fruits.To breed Cu-resistant apple(Malus domestica)cultivars,the underlying molecular mechanisms and key genes involved in Cu resistance must be identified.Here,we show that MdWRKY11 increases Cu tolerance by directly promoting the transcription of MdHMA5.MdHMA5 is a Cu transporter that may function in the storage of excess Cu in root cell walls and stems for Cu tolerance in apple.The transcription factor MdWRKY11 is highly induced by excess Cu.MdWRKY11 overexpression in transgenic apple enhanced Cu tolerance and decreased Cu accumulation.Apple calli transformed with an MdWRKY11-RNAi construct exhibited the opposite phenotype.Both an in vivo chromatin immunoprecipitation assay and an in vitro electrophoretic mobility shift assay indicated that MdWRKY11 binds to the promoter of MdHMA5.Furthermore,MdWRKY11 promoted MdHMA5 expression in transgenic apple plants,as revealed by quantitative PCR.Moreover,inhibition of MdWRKY11 expression by RNA interference led to a significant decrease in MdHMA5 transcription.Thus,MdWRKY11 directly regulates MdHMA5 transcription.Our work resulted in the identification of a novel MdWRKY11-MdHMA5 pathway that mediates Cu resistance in apple.展开更多
Iron(Fe)is an essential micronutrient for plants.Fe deficiency,resulting from poor availability induced by its insolubility in most soils,severely affects the growth and yield of apple(Malus domestica Borkh.).Except f...Iron(Fe)is an essential micronutrient for plants.Fe deficiency,resulting from poor availability induced by its insolubility in most soils,severely affects the growth and yield of apple(Malus domestica Borkh.).Except for the application of an Fe nutrition agent,there is a lack of efficient and environmently-friendly ways to relieve plants from Fe deficiency in a modern orchard.Here,we observed that melatonin(MT),as an efficient reactive oxygen species(ROS)scavenger,could alleviate the chlorosis of leaves in apple under Fe deficiency,following increased Fe content,decreased chlorophyll degradation and stable photosynthetic rate.Exogenous melatonin induced the synthesis of endogenous melatonin and improved the activities of antioxidant enzymes,which decreased the oxidative damage induced by Fe deficiency through properly scavenging O_(2)•−and H_(2)O_(2).In addition,exogenous melatonin promoted the expression of its synthetase genes,but decreased their protein level,inferring post-transcriptional regulation.In brief,melatonin improved the tolerance to Fe deficiency through ROS migration and chloroplast protection in apple.This work uncovered the role of melatonin on Fe deficiency tolerance and also provided a potential way to relieve plants from Fe deficiency stress for apple production.展开更多
A population of 117 doubled haploid(DH)lines derived from the cross of Zhaiyeqing 8(indica)6 Jingxi 17(japonica)was employed to map quantitative trait loci(QTL)underlying four physiological traits related to chlorophy...A population of 117 doubled haploid(DH)lines derived from the cross of Zhaiyeqing 8(indica)6 Jingxi 17(japonica)was employed to map quantitative trait loci(QTL)underlying four physiological traits related to chlorophyll contents of the flag leaf.There were significantly positive correlations among chlorophyll a,chlorophyll b and chlorophyll a+b content.Chlorophyll a/b ratio was significantly negatively correlated with chlorophyll b content.These four traits were normally distributed with transgressive segregation,suggesting that they were controlled by multiple minor genes.A total of 11 QTLs were detected for the four traits and they lay on six chromosomes.Each of them explained 9.2%–19.6%of the phenotypic variations,respectively.Of these,two QTLs controlling chlorophyll a content were mapped on chromosomes 2 and 5;four QTLs underlying chlorophyll b content were mapped on chromosomes 2,3,5 and 9;three QTLs underlying chlorophyll a+b amount were mapped on chromosomes 3,5 and 9;two QTLs underlying chlorophyll a/b ratio were mapped on chromosomes 6 and 11.The intrinsic relationship among the four traits and the practical implication in rice breeding are discussed.展开更多
基金Supported by the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20210347)Supported by the National Natural Science Foundation of China(Grant No.U2141246).
文摘Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is proposed.First,the known flow field data is used to initialize the model parameters,so that the parameters to be trained are close to the optimal value.Then physical prior knowledge is introduced into the training process so that the prediction results not only meet the known flow field information but also meet the physical conservation laws.Through two examples,it is proved that the model under the fusion driven framework can solve the strongly nonlinear flow field problems,and has stronger generalization and expansion.The proposed model is used to solve a muzzle flow field,and the safety clearance behind the barrel side is divided.It is pointed out that the shape of the safety clearance under different launch speeds is roughly the same,and the pressure disturbance in the area within 9.2 m behind the muzzle section exceeds the safety threshold,which is a dangerous area.Comparison with the CFD results shows that the calculation efficiency of the proposed model is greatly improved under the condition of the same calculation accuracy.The proposed model can quickly and accurately simulate the muzzle flow field under various launch conditions.
基金supported by the National Key Research and Development Program of China(SQ2018YFD100303 and 2019YFD1000104)National Natural Science Fund(No.31772279)the Construction of Beijing science and technology innovation and service capacity in top subjects(CEFFPXM2019_014207_000032).
文摘Overuse of fungicides and fertilizers has resulted in copper(Cu)contamination of soils and toxic levels of Cu in apple fruits.To breed Cu-resistant apple(Malus domestica)cultivars,the underlying molecular mechanisms and key genes involved in Cu resistance must be identified.Here,we show that MdWRKY11 increases Cu tolerance by directly promoting the transcription of MdHMA5.MdHMA5 is a Cu transporter that may function in the storage of excess Cu in root cell walls and stems for Cu tolerance in apple.The transcription factor MdWRKY11 is highly induced by excess Cu.MdWRKY11 overexpression in transgenic apple enhanced Cu tolerance and decreased Cu accumulation.Apple calli transformed with an MdWRKY11-RNAi construct exhibited the opposite phenotype.Both an in vivo chromatin immunoprecipitation assay and an in vitro electrophoretic mobility shift assay indicated that MdWRKY11 binds to the promoter of MdHMA5.Furthermore,MdWRKY11 promoted MdHMA5 expression in transgenic apple plants,as revealed by quantitative PCR.Moreover,inhibition of MdWRKY11 expression by RNA interference led to a significant decrease in MdHMA5 transcription.Thus,MdWRKY11 directly regulates MdHMA5 transcription.Our work resulted in the identification of a novel MdWRKY11-MdHMA5 pathway that mediates Cu resistance in apple.
基金supported by the National Key Research&Development Program of China(Project No.2019YFD1000104 and 2018YFD1000303)the National Natural Science Foundation of China(No.31772279)the Construction of Beijing Science and Technology Innovation and Service Capacity in Top Subjects(CEFF-PXM2019_014207_000032).
文摘Iron(Fe)is an essential micronutrient for plants.Fe deficiency,resulting from poor availability induced by its insolubility in most soils,severely affects the growth and yield of apple(Malus domestica Borkh.).Except for the application of an Fe nutrition agent,there is a lack of efficient and environmently-friendly ways to relieve plants from Fe deficiency in a modern orchard.Here,we observed that melatonin(MT),as an efficient reactive oxygen species(ROS)scavenger,could alleviate the chlorosis of leaves in apple under Fe deficiency,following increased Fe content,decreased chlorophyll degradation and stable photosynthetic rate.Exogenous melatonin induced the synthesis of endogenous melatonin and improved the activities of antioxidant enzymes,which decreased the oxidative damage induced by Fe deficiency through properly scavenging O_(2)•−and H_(2)O_(2).In addition,exogenous melatonin promoted the expression of its synthetase genes,but decreased their protein level,inferring post-transcriptional regulation.In brief,melatonin improved the tolerance to Fe deficiency through ROS migration and chloroplast protection in apple.This work uncovered the role of melatonin on Fe deficiency tolerance and also provided a potential way to relieve plants from Fe deficiency stress for apple production.
文摘A population of 117 doubled haploid(DH)lines derived from the cross of Zhaiyeqing 8(indica)6 Jingxi 17(japonica)was employed to map quantitative trait loci(QTL)underlying four physiological traits related to chlorophyll contents of the flag leaf.There were significantly positive correlations among chlorophyll a,chlorophyll b and chlorophyll a+b content.Chlorophyll a/b ratio was significantly negatively correlated with chlorophyll b content.These four traits were normally distributed with transgressive segregation,suggesting that they were controlled by multiple minor genes.A total of 11 QTLs were detected for the four traits and they lay on six chromosomes.Each of them explained 9.2%–19.6%of the phenotypic variations,respectively.Of these,two QTLs controlling chlorophyll a content were mapped on chromosomes 2 and 5;four QTLs underlying chlorophyll b content were mapped on chromosomes 2,3,5 and 9;three QTLs underlying chlorophyll a+b amount were mapped on chromosomes 3,5 and 9;two QTLs underlying chlorophyll a/b ratio were mapped on chromosomes 6 and 11.The intrinsic relationship among the four traits and the practical implication in rice breeding are discussed.
