叶绿素是植物重要的光合色素之一,其含量影响着植物最终合成的生物量或产量。CAO(Chlorophyllide a oxygenas)是叶绿素生物合成的关键限速酶之一,主要参与叶绿素b的形成。为探究杧果CAO基因的生物学功能,本研究利用RACE技术,从杧果‘金...叶绿素是植物重要的光合色素之一,其含量影响着植物最终合成的生物量或产量。CAO(Chlorophyllide a oxygenas)是叶绿素生物合成的关键限速酶之一,主要参与叶绿素b的形成。为探究杧果CAO基因的生物学功能,本研究利用RACE技术,从杧果‘金煌’品种中克隆得到MiCAO基因并对其蛋白序列进行相应的生物信息学分析、构建其植物超表达载体进行亚细胞定位和基因功能验证。本试验克隆了杧果MiCAO基因,该基因全长cDNA序列为2151 bp,开放阅读框为1608 bp,编码535个氨基酸。进化树分析表明,MiCAO蛋白与双子叶植物的开心果Pv CAO蛋白的亲缘关系最近。利用植物瞬时表达技术转化烟草,对MiCAO蛋白进行亚细胞定位显示MiCAO蛋白定位于细胞质和细胞核中;对MiCAO进行基因功能验证,结果表明转基因株系表型与野生型无明显差异,推测MiCAO基因可能不是调控叶绿素生物合成途径中的主效基因,为研究杧果叶绿素生物合成提供了一定的理论参考依据。展开更多
The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This ...The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils.展开更多
Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals ...Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,India.From each active mine,soil samples were randomly collected at distances of<50 m(zone 1),50–100 m(zone 2),and>100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg respectively.From the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal content.Further,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal content.The microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.展开更多
目的:直接测序法及外显子3 DNA片段克隆测序定确认MICA新的等位基因MICA*002:04。方法:用组特异性引物分别扩增MICA基因,采用Sequence Base Typing(SBT)法分型技术及PCR片段克隆测序法对MICA多态性基因的外显子2、3、4、5进行双向测序...目的:直接测序法及外显子3 DNA片段克隆测序定确认MICA新的等位基因MICA*002:04。方法:用组特异性引物分别扩增MICA基因,采用Sequence Base Typing(SBT)法分型技术及PCR片段克隆测序法对MICA多态性基因的外显子2、3、4、5进行双向测序。结果:发现1个与MICA*002:01序列相近的新等位基因,在外显子3上有1个碱基位置与国际通用MICA数据库不相符。该基因与MICA*002:01相比在外显子3的碱基位置486出现突变(C→A),密码子位置20由GCC→GCA,相应编码氨基酸是同义突变。结论:DNA测序结果表明该基因序列为新的MICA等位基因,已提交GenBank,于2010年9月被世界卫生组织HLA因子命名委员会正式命名为MICA*002:04。展开更多
Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energ...Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energy industry has created a favorable policy environment for the development of the lithium battery sector.Against this backdrop,Tianqi Lithium Corp’s acquisition of Sociedad Química y Minera(SQM)in Chile has garnered widespread attention.This paper takes Tianqi Lithium Corp’s acquisition of SQM as the research subject,conducting a detailed analysis of the motives behind the M&A.Subsequently,financial indicators are employed to conduct a performance analysis from a financial perspective,examining the impact of the M&A.Finally,based on the findings of the case analysis,relevant suggestions are proposed to offer a reference for the development of enterprise mergers and acquisitions.展开更多
MICAtronics, based on the functional oxide/mica heterostructures, has recently attracted much attention due to its potential applications in transparent, flexible electronics and devices. However, the weak van der Waa...MICAtronics, based on the functional oxide/mica heterostructures, has recently attracted much attention due to its potential applications in transparent, flexible electronics and devices. However, the weak van der Waals interaction decreases the tolerable lattice mismatch and thus limits the species of function oxides that are able to be epitaxially grown on mica. We successfully fabricate relatively high-quality epitaxial anatase TiO2 thin films on mica substrates. Structural analyses reveal that the carefully chosen growth temperature(650℃) and suitable crystalline phase(anatase phase) of TiO2 are the key issues for this van der Waals epitaxy. Moreover, as a buffer layer, the TiO2 layer successfully suppresses the decomposition of BiFeO3 and the difficulty of epitaxial growth of BiFeO3 is decreased. Therefore, relatively high-quality anatase TiO2 is proved to be an effective buffer layer for fabricating more functional oxides on mica.展开更多
基金The financial supports of the National Natural Science Foundation of China(Grant No.42177148)the opening fund of State Key Laboratory of Geohazard Prevention and Geo-environment Protection(Grant No.SKLGP 2023K011)Postdoctoral Research Project of Guangzhou(Grant No.20220402)are gratefully thanked.
文摘The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils.
文摘Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the crop.The present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,India.From each active mine,soil samples were randomly collected at distances of<50 m(zone 1),50–100 m(zone 2),and>100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg respectively.From the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal content.Further,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal content.The microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.
文摘目的:直接测序法及外显子3 DNA片段克隆测序定确认MICA新的等位基因MICA*002:04。方法:用组特异性引物分别扩增MICA基因,采用Sequence Base Typing(SBT)法分型技术及PCR片段克隆测序法对MICA多态性基因的外显子2、3、4、5进行双向测序。结果:发现1个与MICA*002:01序列相近的新等位基因,在外显子3上有1个碱基位置与国际通用MICA数据库不相符。该基因与MICA*002:01相比在外显子3的碱基位置486出现突变(C→A),密码子位置20由GCC→GCA,相应编码氨基酸是同义突变。结论:DNA测序结果表明该基因序列为新的MICA等位基因,已提交GenBank,于2010年9月被世界卫生组织HLA因子命名委员会正式命名为MICA*002:04。
文摘Enterprise mergers and acquisitions(M&A)are vital strategies for companies worldwide to expand markets,enhance competitiveness,and achieve strategic goals.The Chinese government’s strong support for the new energy industry has created a favorable policy environment for the development of the lithium battery sector.Against this backdrop,Tianqi Lithium Corp’s acquisition of Sociedad Química y Minera(SQM)in Chile has garnered widespread attention.This paper takes Tianqi Lithium Corp’s acquisition of SQM as the research subject,conducting a detailed analysis of the motives behind the M&A.Subsequently,financial indicators are employed to conduct a performance analysis from a financial perspective,examining the impact of the M&A.Finally,based on the findings of the case analysis,relevant suggestions are proposed to offer a reference for the development of enterprise mergers and acquisitions.
基金Supported by the National Key Research and Development Program of China under Grant No 2016YFA0300102the National Natural Science Foundation of China under Grant Nos 11675179,11434009 and 11374010the Fundamental Research Funds for the Central Universities under Grant No WK2340000065
文摘MICAtronics, based on the functional oxide/mica heterostructures, has recently attracted much attention due to its potential applications in transparent, flexible electronics and devices. However, the weak van der Waals interaction decreases the tolerable lattice mismatch and thus limits the species of function oxides that are able to be epitaxially grown on mica. We successfully fabricate relatively high-quality epitaxial anatase TiO2 thin films on mica substrates. Structural analyses reveal that the carefully chosen growth temperature(650℃) and suitable crystalline phase(anatase phase) of TiO2 are the key issues for this van der Waals epitaxy. Moreover, as a buffer layer, the TiO2 layer successfully suppresses the decomposition of BiFeO3 and the difficulty of epitaxial growth of BiFeO3 is decreased. Therefore, relatively high-quality anatase TiO2 is proved to be an effective buffer layer for fabricating more functional oxides on mica.
