Due to imperfect manufacturing technology, design defects and environmental impact, the failure rate of 10 kV switchgear is very high. For this reason, based on taken present situation of traditional switchgear and th...Due to imperfect manufacturing technology, design defects and environmental impact, the failure rate of 10 kV switchgear is very high. For this reason, based on taken present situation of traditional switchgear and the current technical requirements for switchgear into account, a new reliable and safe modular high voltage switchgear design method is presented in this paper, which can reduce the failure rate of switchgear and improve the reliability of power supply. The electric field and temperature rise simulation model are established to check the reasonability and validity. By using the finite element software, the simulation results show that the design in this paper has a maximum temperature rise of 55 K for the main cabinet and a maximum temperature rise of 45 K for the deputy cabinet, which is far below the international standard of 70 K. The areas where the partial discharge is likely to occur within the switchgear are places such as the connection between bus-bar and cabinet, bus-bar joint and bus-bar corner. In order to avoid potential dangers, the discharge point must be located in time to prevent insulation fault of electrical equipment of the high voltage switchgear. The simulation results demonstrate that the design method in this paper greatly improve the reliability of switchgear and meets the demands of power system.展开更多
Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and ...Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and their underlying mechanism remains largely unknown. Here, we report a rice floury endosperm22(flo22) mutant with delayed amyloplast development in endosperm cells. Map-based cloning and complementation tests demonstrated that FLO22 encodes a mitochondrion-localized P-type PPR protein.Mutation of FLO22 resulting in defective transsplicing of mitochondrial nad1 intron 1 and perhaps causing instability of mature transcripts affected assembly and activity of complex Ⅰ, and mitochondrial morphology and function. RNA-seq analysis showed that expression levels of many genes involved in starch and sucrose metabolism were significantly down-regulated in the flo22mutant compared with the wild type, whereas genes related to oxidative phosphorylation and the tricarboxylic acid cycle were significantly upregulated. In addition to involvement in splicing as a P-type PPR protein, we found that FLO22 interacted with DYW3, a DYW-type PPR protein, and they may function synergistically in mitochondrial RNA editing. The present work indicated that FLO22 plays an important role in endosperm development and plant growth by participating in nad1 maturation and multi-site editing of mitochondrial messager RNA.展开更多
Dear Editor,Sources of genetic variations in genomes include small-scale sources(such as single-nucleotide polymorphisms(SNPs),insertions/deletions(InDels),and simple sequence repeats and larger-scale structural varia...Dear Editor,Sources of genetic variations in genomes include small-scale sources(such as single-nucleotide polymorphisms(SNPs),insertions/deletions(InDels),and simple sequence repeats and larger-scale structural variations(mainly presence-absence variants(PAVs))and copy number variants).PAVs are sequences that are either inserted or missing in genomes in comparison with a reference sequence or genome.PAVs can have a much longer sequence than SNPs and InDels,as illustrated in the human genome(Conrad et al.,2010).PAVs are important genomic structural variations that can directly affect genomic structure and key functional genes in the genome(Kumar et al.,2007).Moreover,the use of PAVs for studying quantitative traits has been valuable(Lam et al.,2010).展开更多
文摘Due to imperfect manufacturing technology, design defects and environmental impact, the failure rate of 10 kV switchgear is very high. For this reason, based on taken present situation of traditional switchgear and the current technical requirements for switchgear into account, a new reliable and safe modular high voltage switchgear design method is presented in this paper, which can reduce the failure rate of switchgear and improve the reliability of power supply. The electric field and temperature rise simulation model are established to check the reasonability and validity. By using the finite element software, the simulation results show that the design in this paper has a maximum temperature rise of 55 K for the main cabinet and a maximum temperature rise of 45 K for the deputy cabinet, which is far below the international standard of 70 K. The areas where the partial discharge is likely to occur within the switchgear are places such as the connection between bus-bar and cabinet, bus-bar joint and bus-bar corner. In order to avoid potential dangers, the discharge point must be located in time to prevent insulation fault of electrical equipment of the high voltage switchgear. The simulation results demonstrate that the design method in this paper greatly improve the reliability of switchgear and meets the demands of power system.
基金supported by grants from the National Key R&D Program of China (2021YFF1000200)National Natural Science Foundation of China (31901513)+6 种基金the “JBGS” Project of Seed Industry Revitalization in Jiangsu Province (JBGS [2021]008)Jiangsu Province Agriculture Independent Innovation Fund Project (CX(19)1002)the Fundamental Research Funds for the Central Universities (KJQN202005)the China Postdoctoral Science Foundation (2019M661864)also supported by the Key Laboratory of Biology, Genetics, and Breeding of Japonica Rice in Mid-lower Yangtze River, Ministry of Agriculture, Chinathe Jiangsu Collaborative Innovation Center for Modern Crop ProductionNational Observation and Research Station of Rice Germplasm Resources, Nanjing, Jiangsu。
文摘Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and their underlying mechanism remains largely unknown. Here, we report a rice floury endosperm22(flo22) mutant with delayed amyloplast development in endosperm cells. Map-based cloning and complementation tests demonstrated that FLO22 encodes a mitochondrion-localized P-type PPR protein.Mutation of FLO22 resulting in defective transsplicing of mitochondrial nad1 intron 1 and perhaps causing instability of mature transcripts affected assembly and activity of complex Ⅰ, and mitochondrial morphology and function. RNA-seq analysis showed that expression levels of many genes involved in starch and sucrose metabolism were significantly down-regulated in the flo22mutant compared with the wild type, whereas genes related to oxidative phosphorylation and the tricarboxylic acid cycle were significantly upregulated. In addition to involvement in splicing as a P-type PPR protein, we found that FLO22 interacted with DYW3, a DYW-type PPR protein, and they may function synergistically in mitochondrial RNA editing. The present work indicated that FLO22 plays an important role in endosperm development and plant growth by participating in nad1 maturation and multi-site editing of mitochondrial messager RNA.
基金Supported by the National Key Research and Development Program of China (2016YFD0100300)the National Natural Science Foundation of China (31600223)+4 种基金the Natural Science Basic Research Plan in Shaanxi Province (2019JQ-062)the Shaanxi Youth Entrusted Talents Program (20190205)the Shaanxi Postdoctoral Project (2018BSHYDZZ76)the National Natural Science Foundation of China (31872175)and the State Key Laboratory of Cotton Biology Open Fund (CB2018A07, CB2019A03, and 2019A09).
文摘Dear Editor,Sources of genetic variations in genomes include small-scale sources(such as single-nucleotide polymorphisms(SNPs),insertions/deletions(InDels),and simple sequence repeats and larger-scale structural variations(mainly presence-absence variants(PAVs))and copy number variants).PAVs are sequences that are either inserted or missing in genomes in comparison with a reference sequence or genome.PAVs can have a much longer sequence than SNPs and InDels,as illustrated in the human genome(Conrad et al.,2010).PAVs are important genomic structural variations that can directly affect genomic structure and key functional genes in the genome(Kumar et al.,2007).Moreover,the use of PAVs for studying quantitative traits has been valuable(Lam et al.,2010).