Tomato yellow leaf curl virus(TYLCV)is the dominating pathogen of tomato yellow leaf curl disease that caused severe loss to tomato production in China.In this study,we found that a TYLCV-resistant tomato line drastic...Tomato yellow leaf curl virus(TYLCV)is the dominating pathogen of tomato yellow leaf curl disease that caused severe loss to tomato production in China.In this study,we found that a TYLCV-resistant tomato line drastically reduced the accumulation of viral complementary-sense strand mRNAs but just moderately inhibited that of viral DNA and virion-sense strand mRNAs.However,two other resistant lines did not have such virus inhibition pattern.Analysis of differential expressed genes showed that the potential host defense-relevant processes varied in different resistant tomatoes,as compared to the susceptible line,suggesting a diversity of tomato TYLCV-resistance mechanisms.展开更多
Analysis of climatological observation temperature data reveals that during the southwesterly monsoon, there exists a low tempera- ture zone east of Vietnam. It cools down from June to August and warms up in September...Analysis of climatological observation temperature data reveals that during the southwesterly monsoon, there exists a low tempera- ture zone east of Vietnam. It cools down from June to August and warms up in September. Meanwhile, during this period, the cold water mass spreads eastward to the deep basin. Numerical experiments validate the results of data analysis and further verify that there are two basic factors that induce the Vietnam cold water. The major one is the strong local positive wind stress curl, which leads to the divergence of sea surface water and the upward supplement of lower layer water in the deep basin. Another minor one is the alongshore component of southwesterly monsoon, which drives the offshore Ekman transport and coastal upwelling in the shallow region along the Vietnam coast. In addition, the negative wind stress curl in the southern South China Sea inputs negative vorticity to the ocean and drives a strong anticyclonic gyre, which affects the spatial distribution of the cold water evidently.展开更多
It has been reported that squash leaf curl China virus(SLCCNV)infects some Cucurbitaceae crops except for melon(Cucumis melo L.).A new disease of melon exhibiting severe leaf curl and dwarfing was observed in Hainan P...It has been reported that squash leaf curl China virus(SLCCNV)infects some Cucurbitaceae crops except for melon(Cucumis melo L.).A new disease of melon exhibiting severe leaf curl and dwarfing was observed in Hainan Province of China.In this study,the pathogen was identified as SLCCNV through biological and molecular characterization.The isolate(SLCCNV-HN)possess a bipartite genome,DNA-A(HM566112.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062251.1)pumpkin and SLCCNV-Hn61(AM260205.1)squash isolates from China,whereas DNA-B(HM566113.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062252.1).Phylogenetic analyses based on the full-length SLCCNV-HN DNA-A and-B sequences indicated that SLCCNV-HN melon isolate is clustered with SLCCNV-Hn pumpkin,SLCCNV-Hn61 and SLCCNV-SY squash isolates from southern China,forming an independent cluster.Infectious clone of SLCCNV-HN was constructed and the melon plants were inoculated and the infection rate is 100%,the systemic symptoms in melon showed identical to those of melon plants infected in fields.Additionally,melon plants transmission of this virus by Bemisia tabaci with a transmission rate of 95%(19/20)showed leaf curl and dwarf symptoms 15 days post transmission,thereby fulfilling Koch’s postulates.Analysis of genomic organization and phylogenetic trees indicated that SLCCNV-HN melon isolate belongs to the Begomovirus genus.To the best of our knowledge,this is the first characterization of meloninfecting SLCCNV through its genome,infectious clone and transmission.展开更多
Tomato yellow leaf curl virus(TYLCV)is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein(CP)gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21(...Tomato yellow leaf curl virus(TYLCV)is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein(CP)gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21(DE3)using pET-32a as the expression vector.The recombinant protein was purified through Ni+-NTA affinity column and used to immunize BALB/c mice.Three hybridoma cell lines(2B2,2E3 and 3E10)secreting monoclonal antibodies(MAbs)against TYLCV CP were obtained by fusing mouse myeloma cells(Sp 2/0)with spleen cells from the immunized BALB/c mouse.The titers of ascitic fluids of three MAbs ranged from 10-6 to 10-7 in indirect-ELISA.Isotypes and subclasses of all the MAbs belonged to IgG1,κ light chain.Triple antibody sandwich enzyme-linked immunosorbent assay(TAS-ELISA)showed that the MAb 3E10 could react with five begomoviruses infecting tomato,while the other two(2B2 and 2E3)mainly reacted with TYLCV.TAS-ELISA was set up using the MAb 3E10,and the established method could successfully detect virus in plant sap at 1:2 560(w/v,g mL-1).Detection of field samples showed that begomoviruses were common in tomato crops in Zhejiang Province,China.展开更多
[Objectives]In 2019,virus diseases occurred widely on zucchini planted in Shandong Province.The disease symptom was different from previous reports.This study aimed to identify the pathogen causing the zucchini virus ...[Objectives]In 2019,virus diseases occurred widely on zucchini planted in Shandong Province.The disease symptom was different from previous reports.This study aimed to identify the pathogen causing the zucchini virus disease.[Methods]Ten diseased zucchini leaves were collected in the field and used as materials for PCR and sequencing.[Results]PCR detection and sequencing showed that the nucleotide sequence of the amplified fragment had the highest identity with the squash isolate of squash leaf curl China virus(SLCCNV)(MW389919.1)in Guangdong Province.Primers were further designed for amplifying the full-length SLCCNV.The full-length DNA-A was 2730 bp(OM692270.1),and the full-length DNA-B was 2711 bp(OM692269.1).Through sequence alignment,it was found that the DNA-A sequence shared identity of 89.65%-99.42%with registered SLCCNV,and the identity with the SLCCNV-GDHY pumpkin isolate(MW389919.1)in Guangdong was the highest,at 99.42%.The DNA-B sequence was identical with registered SLCCNV in the range of 81.82%-97.29%,and the identity with the SLCCNV-GDHY pumpkin isolate(MW389918.1)in Guangdong,was the highest,at 97.29%.Therefore,it was speculated that SLCCNV is the pathogen of zucchini virus disease.Since the virus was first found on zucchini in Shandong,it was named SLCCNV-SD.[Conclusions]This study provides materials for the research on the spread of SLCCNV in China and the analysis of population genetic characteristics,as well as a reference for the prevention and control of the virus in zucchini.展开更多
Soil curling is an important phenomenon associated with volume changes induced by increasing soil suction upon desiccation.The study of soil behaviors associated with drying in soils(e.g.soil shrinkage,desiccation cra...Soil curling is an important phenomenon associated with volume changes induced by increasing soil suction upon desiccation.The study of soil behaviors associated with drying in soils(e.g.soil shrinkage,desiccation cracks and curling)has received increasing attention over the last few years,which has been mainly driven by the forecast climate change that will warm up our planet.There are significant gaps in the current knowledge related to the factors that control the development of curling deformations in soils.For this,the curling phenomenon is investigated through laboratory desiccation tests on different mixtures of artificial soils.The effects of soil grain size distribution,mineralogy,soil microstructure,and soil water content on the curling deformation are analyzed.Digital photos were taken at regular time intervals during the tests to understand the volume changes in the soil samples during drying.It is found that soil fabric and soil water content have significant effects on curling scenario.It is observed that the percentage of sand particles and the initial water content play a critical role in the development of soil curling.Samples of pure clayey minerals experienced shrinkage without or with minor curling during drying.展开更多
Lithium–sulfur(Li–S) batteries have received more and more attention because of higher specific capacity and energy density of sulfur than current lithium–ion batteries. However, the low electrical conductivity o...Lithium–sulfur(Li–S) batteries have received more and more attention because of higher specific capacity and energy density of sulfur than current lithium–ion batteries. However, the low electrical conductivity of sulfur and its discharge product, and also the high dissolution of polysulfides restrict the Li–S battery practical applications. To improve their performances, in this work, we fabricate a novel free-standing, curled and partially reduced graphene oxide(CPrGO for short) network and combine it with sulfur to form a CPrGO–S composite as a cathode for Li–S battery. With sulfur content of 60 wt%, the free-standing CPrGO–S composite network delievers an initial capacity of 988.9 m Ah·g^(-1). After 200 cycles,it shows a stable capacity of 841.4 m Ah·g^(-1) at 0.2 C, retaining about 85% of the initial value. The high electrochemical performance demonstrates that the CPrGO–S network has great potential applications in energy storage system. Such improved properties can be ascribed to the unique free-standing and continous CPrGO–S network which has high specific surface area and good electrical conductivity. In addition, oxygen-containing groups on the partially reduced graphene oxide are beneficial to preventing the polysulfides from dissolving into electrolyte and can mitigate the "shuttle effect".展开更多
To identify the inheritance pattern and perform fne mapping of ty-5 gene, P1, P2, F1, BC1 and F2 generations were obtained through a cross between CLN32120a-23 (containing ty-5 gene, P1) and S. lycopersicum Moneymak...To identify the inheritance pattern and perform fne mapping of ty-5 gene, P1, P2, F1, BC1 and F2 generations were obtained through a cross between CLN32120a-23 (containing ty-5 gene, P1) and S. lycopersicum Moneymaker (fully susceptible, P2). The results showed that resistance of ty-5 gene was determined by a recessive effect. Meanwhile, it was presumed that another resistance gene might be involved in mediating the resistance to tomato yellow leaf curl virus (TYLCV). In this study, fne mapping was used to map TYLCV resistance locus to an interval between NAC1 and TES2461 on the short arm of chromosome 4 with genetic distances of 0.5 and 0.8 cM, respectively. qRT-PCR results showed that four candidate genes, SlNAC1; LOC104229164; LOC101260925 and LOC101261508 having resistance-related expression patterns, were the likely target genes of ty-5. In addition, it was found that the codominant marker TES2461 could be used in marker-assisted selection (MAS) breeding. The fndings of this research provided the basis for future cloning of ty-5 gene as well as MAS breeding and plant resistance mechanism studies.展开更多
This paper concerns the minimization problem of L2 norm of curl of vector fields prescribed full trace on the boundary of a multiconnected bounded domain.The existence of the minimizers in H1 are shown by orthogonal d...This paper concerns the minimization problem of L2 norm of curl of vector fields prescribed full trace on the boundary of a multiconnected bounded domain.The existence of the minimizers in H1 are shown by orthogonal decompositions of vector function spaces and a constructed auxiliary variational problem.And the H2 estimate of the type II divergence-free part of the minimizers is established by div-curl-gradient type estimates of vector fields.展开更多
Sweet potato is one of the first natural GMOs, genetically modified 8000 years ago by Agrobacterium rhizogenes as reported recently by Kyndt et al. A section of 10 kbp long DNA (Transferred- DNA or T-DNA) of the Ri (R...Sweet potato is one of the first natural GMOs, genetically modified 8000 years ago by Agrobacterium rhizogenes as reported recently by Kyndt et al. A section of 10 kbp long DNA (Transferred- DNA or T-DNA) of the Ri (Root-inducing) plasmid was transferred to the plant genome by A. rhizo-genes and has been maintained in all 291 hexaploid sweet potato cultivars of the world. The maintenance in the sweet potato genome and expression of two T-DNA genes for tryptophan-2-monooxygenease (iaaM) and for indole-3-acetamide hydrolase (iaaH) are likely to be physiologically significant since these enzymes convert tryptophan to indole-3-acetic acid, a major plant growth hormone auxin. Sweet potato (Ipomoea batatas (L.) Lam) is ranked the third most important root crop after potato and cassava, and the seventh in global food crop production with more than 126 million metric tons. Although sweet potato originated in Central or South America, China currently produces over 86% of world production with 109 million metric tons. In the United States, North Carolina is the leading producer with 38.5% of the 2007 sweet potato production, followed by California, Mississippi, and Louisiana with 23%, 19%, and 15.9%, respectively. Leaf curl virus diseases have been reported in sweet potato throughout the world. One of the causal agents is Sweet potato leaf curl virus (SPLCV) belonging to the genus Begomovirus (family Geminiviridae). Although SPLCV does not cause symptoms on Beauregard, one of the most predominant sweet potato cultivars in the US, it can reduce the yield up to 26%. Serological detection of SPLCV is not currently available due to the difficulties in obtaining purified virions that can be used as antigen for antiserum production. In attempts to obtain the coat protein (CP) of SPLCV for antibody production, primers were designed to amplify the CP gene. This gene was cloned into the expression vector pMAL-c2E as a fusion protein with maltose-binding protein, and transformed into Escherichia coli strain XL1-Blue. After gene induction, a fusion protein of 72 kDa was purified by amylose affinity chromatography. The yield of the purified fusion protein was approximately 200 μg/liter of bacterial culture. Digestion with enterokinase cleaved the fusion protein into a 42.5 kDa maltosebinding protein and a 29.4 kDa protein. The latter protein was identified by mass spectrometry analysis as the coat protein of SPLCV based on the fact that the mass spectrometry elucidated the sequences corresponding to 37% of amino acid positions of the SPLCV coat protein.展开更多
Between June 2015 and June 2017,two pressure-recording inverted echo sounders(PIESs)and five current and pressure-recording inverted echo sounders(CPIESs)deployed along a section across the Kerama Gap acquired a datas...Between June 2015 and June 2017,two pressure-recording inverted echo sounders(PIESs)and five current and pressure-recording inverted echo sounders(CPIESs)deployed along a section across the Kerama Gap acquired a dataset of ocean bottom pressure records in which there was significant 21-day variability(Pbot21).The Pbot21,which was particularly strong from July-December 2016,was coherent with wind stress curl(WSC)on the continental shelf of the East China Sea(ECS)with a squared coherence of 0.65 for a 3-day time lag.A barotropic ocean model demonstrated the generation,propagation,and dissipation of Pbot21.The modeled results show that the Pbot21 driven by coastal ocean WSC in the ECS propagated toward the Ryukyu Island Chain(RIC),while deep ocean WSC could not induce such variability.On the continental shelf,the Pbot21 was generated nearly synchronously with the WSC from the coastline to the southeast but dissipated within a few days due to the effect of bottom friction.The detection of Pbot21 by the moored array was dependent on the 21-day WSC patterns on the continental shelf.The Pbot21 driven southeast of the Changjiang Estuary by the WSC was detected while the Pbot21generated northeast of the Changjiang Estuary was not.展开更多
基金Supported by Guangzhou Science and Technology Plan(201804010327,202002020040,202102080340)Agricultural Science-Technology Innovation and Promotion Project(2023KJ133)。
文摘Tomato yellow leaf curl virus(TYLCV)is the dominating pathogen of tomato yellow leaf curl disease that caused severe loss to tomato production in China.In this study,we found that a TYLCV-resistant tomato line drastically reduced the accumulation of viral complementary-sense strand mRNAs but just moderately inhibited that of viral DNA and virion-sense strand mRNAs.However,two other resistant lines did not have such virus inhibition pattern.Analysis of differential expressed genes showed that the potential host defense-relevant processes varied in different resistant tomatoes,as compared to the susceptible line,suggesting a diversity of tomato TYLCV-resistance mechanisms.
基金supported by the Chinese Academy of Sciences under contract No.kzcx3-sw-227the National Natural Science Foundation of China under contract No.40406006.
文摘Analysis of climatological observation temperature data reveals that during the southwesterly monsoon, there exists a low tempera- ture zone east of Vietnam. It cools down from June to August and warms up in September. Meanwhile, during this period, the cold water mass spreads eastward to the deep basin. Numerical experiments validate the results of data analysis and further verify that there are two basic factors that induce the Vietnam cold water. The major one is the strong local positive wind stress curl, which leads to the divergence of sea surface water and the upward supplement of lower layer water in the deep basin. Another minor one is the alongshore component of southwesterly monsoon, which drives the offshore Ekman transport and coastal upwelling in the shallow region along the Vietnam coast. In addition, the negative wind stress curl in the southern South China Sea inputs negative vorticity to the ocean and drives a strong anticyclonic gyre, which affects the spatial distribution of the cold water evidently.
基金supported by the National Natural Science Foundation of China (31701941 and 31401810)the grants from the earmarked fund for China Agriculture Research System (CARS-26-13)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (ASTIP) (CAAS-ASTIP-2018-ZFRI-08)
文摘It has been reported that squash leaf curl China virus(SLCCNV)infects some Cucurbitaceae crops except for melon(Cucumis melo L.).A new disease of melon exhibiting severe leaf curl and dwarfing was observed in Hainan Province of China.In this study,the pathogen was identified as SLCCNV through biological and molecular characterization.The isolate(SLCCNV-HN)possess a bipartite genome,DNA-A(HM566112.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062251.1)pumpkin and SLCCNV-Hn61(AM260205.1)squash isolates from China,whereas DNA-B(HM566113.1)with the highest nucleotide identity(99%)to SLCCNV-Hn(MF062252.1).Phylogenetic analyses based on the full-length SLCCNV-HN DNA-A and-B sequences indicated that SLCCNV-HN melon isolate is clustered with SLCCNV-Hn pumpkin,SLCCNV-Hn61 and SLCCNV-SY squash isolates from southern China,forming an independent cluster.Infectious clone of SLCCNV-HN was constructed and the melon plants were inoculated and the infection rate is 100%,the systemic symptoms in melon showed identical to those of melon plants infected in fields.Additionally,melon plants transmission of this virus by Bemisia tabaci with a transmission rate of 95%(19/20)showed leaf curl and dwarf symptoms 15 days post transmission,thereby fulfilling Koch’s postulates.Analysis of genomic organization and phylogenetic trees indicated that SLCCNV-HN melon isolate belongs to the Begomovirus genus.To the best of our knowledge,this is the first characterization of meloninfecting SLCCNV through its genome,infectious clone and transmission.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest from the Ministry of Agriculture,China(201003065)
文摘Tomato yellow leaf curl virus(TYLCV)is a species of the family Geminiviridae,causing serious yield losses in tomato production.The coat protein(CP)gene of TYLCV isolate SH2 was expressed in Escherichia coli BL21(DE3)using pET-32a as the expression vector.The recombinant protein was purified through Ni+-NTA affinity column and used to immunize BALB/c mice.Three hybridoma cell lines(2B2,2E3 and 3E10)secreting monoclonal antibodies(MAbs)against TYLCV CP were obtained by fusing mouse myeloma cells(Sp 2/0)with spleen cells from the immunized BALB/c mouse.The titers of ascitic fluids of three MAbs ranged from 10-6 to 10-7 in indirect-ELISA.Isotypes and subclasses of all the MAbs belonged to IgG1,κ light chain.Triple antibody sandwich enzyme-linked immunosorbent assay(TAS-ELISA)showed that the MAb 3E10 could react with five begomoviruses infecting tomato,while the other two(2B2 and 2E3)mainly reacted with TYLCV.TAS-ELISA was set up using the MAb 3E10,and the established method could successfully detect virus in plant sap at 1:2 560(w/v,g mL-1).Detection of field samples showed that begomoviruses were common in tomato crops in Zhejiang Province,China.
基金Supported by Shandong Province Key R&D Program(2021LZGC015)Taishan Industry Leading Talent Project(LJNY201812)。
文摘[Objectives]In 2019,virus diseases occurred widely on zucchini planted in Shandong Province.The disease symptom was different from previous reports.This study aimed to identify the pathogen causing the zucchini virus disease.[Methods]Ten diseased zucchini leaves were collected in the field and used as materials for PCR and sequencing.[Results]PCR detection and sequencing showed that the nucleotide sequence of the amplified fragment had the highest identity with the squash isolate of squash leaf curl China virus(SLCCNV)(MW389919.1)in Guangdong Province.Primers were further designed for amplifying the full-length SLCCNV.The full-length DNA-A was 2730 bp(OM692270.1),and the full-length DNA-B was 2711 bp(OM692269.1).Through sequence alignment,it was found that the DNA-A sequence shared identity of 89.65%-99.42%with registered SLCCNV,and the identity with the SLCCNV-GDHY pumpkin isolate(MW389919.1)in Guangdong was the highest,at 99.42%.The DNA-B sequence was identical with registered SLCCNV in the range of 81.82%-97.29%,and the identity with the SLCCNV-GDHY pumpkin isolate(MW389918.1)in Guangdong,was the highest,at 97.29%.Therefore,it was speculated that SLCCNV is the pathogen of zucchini virus disease.Since the virus was first found on zucchini in Shandong,it was named SLCCNV-SD.[Conclusions]This study provides materials for the research on the spread of SLCCNV in China and the analysis of population genetic characteristics,as well as a reference for the prevention and control of the virus in zucchini.
文摘Soil curling is an important phenomenon associated with volume changes induced by increasing soil suction upon desiccation.The study of soil behaviors associated with drying in soils(e.g.soil shrinkage,desiccation cracks and curling)has received increasing attention over the last few years,which has been mainly driven by the forecast climate change that will warm up our planet.There are significant gaps in the current knowledge related to the factors that control the development of curling deformations in soils.For this,the curling phenomenon is investigated through laboratory desiccation tests on different mixtures of artificial soils.The effects of soil grain size distribution,mineralogy,soil microstructure,and soil water content on the curling deformation are analyzed.Digital photos were taken at regular time intervals during the tests to understand the volume changes in the soil samples during drying.It is found that soil fabric and soil water content have significant effects on curling scenario.It is observed that the percentage of sand particles and the initial water content play a critical role in the development of soil curling.Samples of pure clayey minerals experienced shrinkage without or with minor curling during drying.
基金supported by the National Basic Research Program of China(Grant No.2012CB932302)the National Natural Science Foundation of China(Grant Nos.11634014,51172271,and 51372269)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA09040202)
文摘Lithium–sulfur(Li–S) batteries have received more and more attention because of higher specific capacity and energy density of sulfur than current lithium–ion batteries. However, the low electrical conductivity of sulfur and its discharge product, and also the high dissolution of polysulfides restrict the Li–S battery practical applications. To improve their performances, in this work, we fabricate a novel free-standing, curled and partially reduced graphene oxide(CPrGO for short) network and combine it with sulfur to form a CPrGO–S composite as a cathode for Li–S battery. With sulfur content of 60 wt%, the free-standing CPrGO–S composite network delievers an initial capacity of 988.9 m Ah·g^(-1). After 200 cycles,it shows a stable capacity of 841.4 m Ah·g^(-1) at 0.2 C, retaining about 85% of the initial value. The high electrochemical performance demonstrates that the CPrGO–S network has great potential applications in energy storage system. Such improved properties can be ascribed to the unique free-standing and continous CPrGO–S network which has high specific surface area and good electrical conductivity. In addition, oxygen-containing groups on the partially reduced graphene oxide are beneficial to preventing the polysulfides from dissolving into electrolyte and can mitigate the "shuttle effect".
基金Supported by the National Key Research and Development Program of China(2016YFD0101703)the Modern Agricultural Technology System of Special Funds(CARS-25-A-15)+2 种基金Breeding of New Vegetable Varieties in Heilongjiang Province(GA15B103)the National Key R&D Program of China(2017YFD0101900)the China Agriculture Research System(CARS-23-A-16)
文摘To identify the inheritance pattern and perform fne mapping of ty-5 gene, P1, P2, F1, BC1 and F2 generations were obtained through a cross between CLN32120a-23 (containing ty-5 gene, P1) and S. lycopersicum Moneymaker (fully susceptible, P2). The results showed that resistance of ty-5 gene was determined by a recessive effect. Meanwhile, it was presumed that another resistance gene might be involved in mediating the resistance to tomato yellow leaf curl virus (TYLCV). In this study, fne mapping was used to map TYLCV resistance locus to an interval between NAC1 and TES2461 on the short arm of chromosome 4 with genetic distances of 0.5 and 0.8 cM, respectively. qRT-PCR results showed that four candidate genes, SlNAC1; LOC104229164; LOC101260925 and LOC101261508 having resistance-related expression patterns, were the likely target genes of ty-5. In addition, it was found that the codominant marker TES2461 could be used in marker-assisted selection (MAS) breeding. The fndings of this research provided the basis for future cloning of ty-5 gene as well as MAS breeding and plant resistance mechanism studies.
基金Supported by the National Natural Science Foundation of China(11501109)Designated Scientific Research Project of Provincial Universities of Fujian Province(JK2015014)。
文摘This paper concerns the minimization problem of L2 norm of curl of vector fields prescribed full trace on the boundary of a multiconnected bounded domain.The existence of the minimizers in H1 are shown by orthogonal decompositions of vector function spaces and a constructed auxiliary variational problem.And the H2 estimate of the type II divergence-free part of the minimizers is established by div-curl-gradient type estimates of vector fields.
文摘Sweet potato is one of the first natural GMOs, genetically modified 8000 years ago by Agrobacterium rhizogenes as reported recently by Kyndt et al. A section of 10 kbp long DNA (Transferred- DNA or T-DNA) of the Ri (Root-inducing) plasmid was transferred to the plant genome by A. rhizo-genes and has been maintained in all 291 hexaploid sweet potato cultivars of the world. The maintenance in the sweet potato genome and expression of two T-DNA genes for tryptophan-2-monooxygenease (iaaM) and for indole-3-acetamide hydrolase (iaaH) are likely to be physiologically significant since these enzymes convert tryptophan to indole-3-acetic acid, a major plant growth hormone auxin. Sweet potato (Ipomoea batatas (L.) Lam) is ranked the third most important root crop after potato and cassava, and the seventh in global food crop production with more than 126 million metric tons. Although sweet potato originated in Central or South America, China currently produces over 86% of world production with 109 million metric tons. In the United States, North Carolina is the leading producer with 38.5% of the 2007 sweet potato production, followed by California, Mississippi, and Louisiana with 23%, 19%, and 15.9%, respectively. Leaf curl virus diseases have been reported in sweet potato throughout the world. One of the causal agents is Sweet potato leaf curl virus (SPLCV) belonging to the genus Begomovirus (family Geminiviridae). Although SPLCV does not cause symptoms on Beauregard, one of the most predominant sweet potato cultivars in the US, it can reduce the yield up to 26%. Serological detection of SPLCV is not currently available due to the difficulties in obtaining purified virions that can be used as antigen for antiserum production. In attempts to obtain the coat protein (CP) of SPLCV for antibody production, primers were designed to amplify the CP gene. This gene was cloned into the expression vector pMAL-c2E as a fusion protein with maltose-binding protein, and transformed into Escherichia coli strain XL1-Blue. After gene induction, a fusion protein of 72 kDa was purified by amylose affinity chromatography. The yield of the purified fusion protein was approximately 200 μg/liter of bacterial culture. Digestion with enterokinase cleaved the fusion protein into a 42.5 kDa maltosebinding protein and a 29.4 kDa protein. The latter protein was identified by mass spectrometry analysis as the coat protein of SPLCV based on the fact that the mass spectrometry elucidated the sequences corresponding to 37% of amino acid positions of the SPLCV coat protein.
基金The SIO group was supported by the National Natural Science Foundation of China under contract Nos41920104006,41806020,41776107 and 41906024the National Programme on Global Change and Air–Sea Interaction under contract No.GASIIPOVAI-01–02+4 种基金the Scientific Research Fund of SIO under contract Nos JZ2001 and JT1801the Project of State Key Laboratory of Satellite Ocean Environment Dynamics,SIO under contract Nos SOEDZZ1901 and SOEDZZ1903the Kagoshima University group was supported by Core Research for Evolutional Science and Technology of the Japan Science and Technology CorporationJSPS KAKENHI under contract Nos JP15H05821 and JP15H03725supported by the“Study on Air–Sea Interaction and Process of Rapidly Intensifying Typhoon in the Northwestern Pacific”project funded by the Ministry of Oceans and Fisheries,Korea。
文摘Between June 2015 and June 2017,two pressure-recording inverted echo sounders(PIESs)and five current and pressure-recording inverted echo sounders(CPIESs)deployed along a section across the Kerama Gap acquired a dataset of ocean bottom pressure records in which there was significant 21-day variability(Pbot21).The Pbot21,which was particularly strong from July-December 2016,was coherent with wind stress curl(WSC)on the continental shelf of the East China Sea(ECS)with a squared coherence of 0.65 for a 3-day time lag.A barotropic ocean model demonstrated the generation,propagation,and dissipation of Pbot21.The modeled results show that the Pbot21 driven by coastal ocean WSC in the ECS propagated toward the Ryukyu Island Chain(RIC),while deep ocean WSC could not induce such variability.On the continental shelf,the Pbot21 was generated nearly synchronously with the WSC from the coastline to the southeast but dissipated within a few days due to the effect of bottom friction.The detection of Pbot21 by the moored array was dependent on the 21-day WSC patterns on the continental shelf.The Pbot21 driven southeast of the Changjiang Estuary by the WSC was detected while the Pbot21generated northeast of the Changjiang Estuary was not.