The electrochemical nitrate reduction reaction(NO_(3)RR)to ammonia under ambient conditions is a promising approach for addressing elevated nitrate levels in water bodies,but the progress of this reaction is impeded b...The electrochemical nitrate reduction reaction(NO_(3)RR)to ammonia under ambient conditions is a promising approach for addressing elevated nitrate levels in water bodies,but the progress of this reaction is impeded by the complex series of chemical reactions involving electron and proton transfer and competing hydrogen evolution reaction.Therefore,it becomes imperative to develop an electro-catalyst that exhibits exceptional efficiency and remarkable selectivity for ammonia synthesis while maintaining long-term stability.Herein the magnetic biochar(Fe-C)has been synthesized by a two-step mechanochemical route after a pyrolysis treatment(450,700,and 1000℃),which not only significantly decreases the particle size,but also exposes more oxygen-rich functional groups on the surface,promoting the adsorption of nitrate and water and accelerating electron transfer to convert it into ammonia.Results showed that the catalyst(Fe-C-700)has an impressive NH_(3)production rate of 3.5 mol·h^(−1)·gcat^(−1),high Faradaic efficiency of 88%,and current density of 0.37 A·cm^(−2)at 0.8 V vs.reversible hydrogen electrode(RHE).In-situ Fourier transform infrared spectroscopy(FTIR)is used to investigate the reaction intermediate and to monitor the reaction.The oxygen functionalities on the catalyst surface activate nitrate ions to form various intermediates(NO_(2),NO,NH_(2)OH,and NH_(2))and reduce the rate determining step energy barrier(*NO_(3)→*NO_(2)).This study presents a novel approach for the use of magnetic biochar as an electro-catalyst in NO_(3)RR and opens the road for solving environmental and energy challenges.展开更多
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)can produce value-added hydrocarbons from renewable electricity,providing a sustainable and promising approach to meet dual-carbon targets and alleviate the e...Electrochemical carbon dioxide reduction reaction(CO_(2)RR)can produce value-added hydrocarbons from renewable electricity,providing a sustainable and promising approach to meet dual-carbon targets and alleviate the energy crisis.However,it is still challenging to improve the selectivity and stability of the products,especially the C^(2+) products.Here we propose to modulate the electronic structure of copper oxide(CuO)through lattice strain construction by zinc(Zn)doping to improve the selectivity of the catalyst to ethylene.Combined performance and in situ characterization analyses show that the compressive strain generated within the CuO lattice and the electronic structure modulation by Zn doping enhances the adsorption of the key intermediate*CO,thereby increasing the intrinsic activity of CO_(2)RR and inhibiting the hydrogen precipitation reaction.Among the best catalysts had significantly improved ethylene selectivity of 60.5%and partial current density of 500 mA·cm^(–2),and the highest C^(2+) Faraday efficiency of 71.47%.This paper provides a simple idea to study the modulation of CO_(2)RR properties by heteroatom doped and lattice strain.展开更多
Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative asses...Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative assessment of filamentous fungal promoters based on flow cytometry detection of the superfolder green fluorescent protein at single-cell resolution.Using this quantitative method,we acquired a library of 93 native promoter elements from Aspergillus nidulans in a high-throughput format.The strengths of identified promoters covered a 37-fold range by flow cytometry.P_(zipA) and P_(sltA)were identified as the strongest promoters,which were 2.9-and 1.5-fold higher than that of the commonly used constitutive promoter P_(gpdA).Thus,we applied P_(zipA)and P_(sltA)to activate the silent nonribosomal peptide synthetase gene Afpes1 from Aspergillus fumigatus in its native host and the heterologous host A.nidulans.The metabolic products of Afpes1 were identified as new cyclic tetrapeptide derivatives,namely,fumiganins A and B.Our method provides an innovative strategy for natural product discovery in fungi.展开更多
Corneal neovascularization(CNV) is one of the major factors for vision impairment and blindness worldwide. The current treatment for CNV focuses primarily on topical eyedrops of glucocorticoids,non-steroidal anti-infl...Corneal neovascularization(CNV) is one of the major factors for vision impairment and blindness worldwide. The current treatment for CNV focuses primarily on topical eyedrops of glucocorticoids,non-steroidal anti-inflammatory drugs, electro-coagulation and laser photo-coagulation. Unfortunately,coagulation-based treatment is restricted by corneal hemorrhage and iris atrophy. And drug treatments have limited therapeutic effects and a short duration of action. Nanoparticle-based drug delivery systems are widely applied due to their improved pharmacokinetics, optimized drug targeting and enhanced biocompatibility. In this article, we provide a comprehensive and systematic overview of the CNV nanodrug system, highlighting some of the recent advances in nanodrug design, preparation, and functional modification. Moreover, we discuss the challenges in the clinical translation and potential risks in CNV treatment. A greater effort is needed for the potential applications of nanotechnology in the field of ophthalmology.展开更多
Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed s...Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed subjects.Induction of temporal heterogenicity in functions in addition to shape may extend the scope of 4D printing.Herein,we report a 4D printing approach using plant protein(zein)gel inspired by the amyloid fibrils formation mechanism.The printing of zein gel in a specialized layered-Carbopol supporting bath with different water concentrations in an ethanol-water mixture modulates hydrophobic and hydrogen bonding that causes temporal changes in functions.The part of the construct printed in a supporting bath with higher water content exhibits higher drug loading,faster drug release and degradation than those printed in the supporting bath with lower water content.Tri-segment conduit and butterfly-shaped construct with two asymmetrical wings are printed using this system to evaluate biomedical function as nerve conduit and drug delivery system.4D printed conduits are also effective as a drug-eluting urethral stent in the porcine model.Overall,this study extends the concept of 4D printing beyond shape transformation and presents an approach of fabricating specialized baths for 4D printing that can also be extended to other materials to obtain 4D printed medical devices with translational potential.展开更多
Laccases, multicopper oxidoreductases, are mainly produced in white-rot fungi and are considered as ideal green catalysts in industrial and biotechnological applications. However, the development of laccases is limite...Laccases, multicopper oxidoreductases, are mainly produced in white-rot fungi and are considered as ideal green catalysts in industrial and biotechnological applications. However, the development of laccases is limited due to the slow growth of natural laccase producing strains and the low expression levels of laccases. In this study, we designed three regulation strategies for laccase gene expression in the model fungus Aspergillus nidulans. By introducing various promoters in front of the laccase gene pslcc from the white-rot fungus Pycnoporus sanguineus, we found that the laccase gene with the original promoter had effective expression in A. nidulans. Using the previously identified transcription factor RsmA regulatory mechanism, the aflR promoter was inserted into the pslcc expression vectors, and the laccase production was 15-fold higher in the strain overexpressing of RsmA compared to the control strain. To improve the laccase yield, the dipeptidyl-peptidase DppV, aspartic protease PepA and mannosyltransferase Mnn9 were successfully deleted in the A. nidulans host. The laccase activities were increased approximately 8-fold and 13-fold in the double deletions strains of Δmnn9ΔpepA and ΔdppVΔpepA over the control strains, respectively.Taken together, these results not only demonstrate an efficient system for heterologous protein production in the model fungus A.nidulans but also provide a general approach to applying regulatory methods to control gene expression.展开更多
In this study,the long-term trend of water vapor over the Tibetan Plateau(TP)in boreal summer is investigated by using observation and reanalysis data from 1979 to 2019.The historical experiment simulations of 19 mode...In this study,the long-term trend of water vapor over the Tibetan Plateau(TP)in boreal summer is investigated by using observation and reanalysis data from 1979 to 2019.The historical experiment simulations of 19 models that participated in the Coupled Model Intercomparison Project phase 6(CMIP6)are evaluated,and the future variation tendency under four emission scenarios is projected.The results indicate that the water vapor content and the net water vapor budget over the TP show notable increasing trends,which are mainly manifested by a significant increase in the net water vapor import and a significant decrease in the water vapor export on the eastern boundary of the TP.This is mainly due to an anomalous anticyclone from Lake Baikal to the Mongolian Plateau.The CMIP6 multi-model ensemble can well simulate the variation characteristics of the TP net water vapor budget.The projection results indicate that by the end of the twenty-first century,the water vapor content,the net water vapor import and precipitation over the TP will increase.Under a high-emissions scenario and compared with the current period(1991–2014),these three variables will increase by 47.99%,59.77%and 18.59%in the long term(2081–2100),respectively.The significant enhancement of meridional water vapor transport over the northern TP may be the main reason for the increase in humidity over the TP.展开更多
Mammalian central nervous system neurons show asymmetry during early brain development that defines the elaborate function of neural circuitry （Kriegstein and Noctor, 2004）. Many intracellular signaling pathways, wh...Mammalian central nervous system neurons show asymmetry during early brain development that defines the elaborate function of neural circuitry （Kriegstein and Noctor, 2004）. Many intracellular signaling pathways, which are important for the transition to the polarized state and the development of axons and dendrites, have been identified （Barnes and Polleux, 2009）. How these pathways are initiated during neuronal development in vivo remained elusive until Yi et al.展开更多
The neoclassical growth model predicts that capital account liberalization could potentially enhance economic performance;however, there is no consistent empirical evidence to support this positive association. Using ...The neoclassical growth model predicts that capital account liberalization could potentially enhance economic performance;however, there is no consistent empirical evidence to support this positive association. Using a novel dataset of Chinese capital account openness, this paper demonstrates a positive relationship between capital account liberalization and aggregate economic performance. The difference-indifferences method is used to capture the causal effect of capital account liberalization on economic performance by taking advantage of variations in both external financial dependence and the progress of capital account openness. We investigate three channels that could strengthen this positive relationship using a firm-level dataset. We find that capital account liberalization could:(i) alleviate the degree of resource misallocation, and this effect is more significant in industries relying heavily on external finance and in regions with more favorable business environments;(ii) enhance firms' total factor productivity;and (iii) promote innovation. Our findings suggest that a strategy of gradual openness will leave some leeway not only for improvement in domestic markets but also to mitigate exposure to unfavorable global shocks.展开更多
The excess amounts of heavy metals are toxic to various physiological processes in plants.Plant metallothioneins(MTs)are low molecular weight,cysteine-rich metal-binding proteins that play important roles in the detox...The excess amounts of heavy metals are toxic to various physiological processes in plants.Plant metallothioneins(MTs)are low molecular weight,cysteine-rich metal-binding proteins that play important roles in the detoxification of heavy metal ions.In this study,we characterized Cs MT4,a plant type 4 MT gene identified in a complementary DNA(cDNA)library prepared from young cucumber(Cucumis sativus)fruit.Cs MT4encodes a 90 amino acid protein with a predicted molecular mass of 9.028 kD.CsMT4 contains 17 cysteine residues in three highly conserved cysteine-rich domains.In contrast to the structures of other MTs,the highly conserved amino acid pattern CxCxxxCxCxxCxC is present in the middle of CsMT4.Furthermore,CsMT4 was markedly induced in various tissues by various concentrations of Cd^(2+)and Zn^(2+)(>1.0 mmol·L^(-1)).Similar to AtMT4b function,heterologous expression of Cs MT4 in E.coli could also improved its tolerance to Cd^(2+)and led to increased uptake of Cd^(2+),and the rate of Cd^(2+)uptake was the highest in cells expressing a phytochelatin-like peptide.Our findings demonstrate that CsMT4 might be obviously induced by the metal stress in cucumber,and improves tolerance to Cd ions but not Zn ions when heterologously expressed in E.coli,and suggest that the composition and arrangement of N-terminal Cys-residues in MT4 are associated with their binding capacity and preference for different metal ions.展开更多
Corneal neovascularization(CNV) can induce severe visual impairment and even blindness.Current treatments have limited efficacy and some undesirable side effects.Phototherapy(FT) is a modern medical technique in CNV t...Corneal neovascularization(CNV) can induce severe visual impairment and even blindness.Current treatments have limited efficacy and some undesirable side effects.Phototherapy(FT) is a modern medical technique in CNV treatment and worth further improvement.Nanotechnology has various advantages and nanoparticle-mediated drug delive ry also contributes to CNV elimination.Phototherapy combined with functional nanoparticles featuring photoacoustic imaging contrast properties can accomplish accurate and safe inhibition of CNV,thus is promising in clinical application.展开更多
Uncertainty induced by the political environment affects investment risk, and thus affects investment decisions, which have a close relationship with economic development. This paper investigates the economic cost of ...Uncertainty induced by the political environment affects investment risk, and thus affects investment decisions, which have a close relationship with economic development. This paper investigates the economic cost of political instability using the case study of the tense relationship across-Strait in China. We use a synthetic control method to better model the counterfactual analysis of this case study. The intense situation of the relations across-Strait has great influence on the economic development of Fujian province. Fujian province is the closest province in proximity to Taiwan and also possesses the greatest preferential policies for Taiwan Residents direct investment. The empirical results of this study reveal that during 2001-2008 Fujian province＇s average annual loss in GDP per capita was 682.54 yuan. In other words, GDP per capita in Fujian has declined about 12.1 percent annually during this period compared with GDP per capita as calculated by the synthetic control method.展开更多
基金the National Natural Science Foundation of China(Nos.52072152 and 51802126)the Jiangsu University Jinshan Professor Fund,the Jiangsu Specially-Appointed Professor Fund,Open Fund from Guangxi Key Laboratory of Electrochemical Energy Materials,Zhenjiang“Jinshan Talents”Project 2021,China PostDoctoral Science Foundation(No.2022M721372)+3 种基金“Doctor of Entrepreneurship and Innovation”in Jiangsu Province(No.JSSCBS20221197)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX22_3645)the National Natural Science Foundation of China(No.22208134)Jiangsu Agricultural Science and Technology Innovation Fund(No.CX(21)1010).
文摘The electrochemical nitrate reduction reaction(NO_(3)RR)to ammonia under ambient conditions is a promising approach for addressing elevated nitrate levels in water bodies,but the progress of this reaction is impeded by the complex series of chemical reactions involving electron and proton transfer and competing hydrogen evolution reaction.Therefore,it becomes imperative to develop an electro-catalyst that exhibits exceptional efficiency and remarkable selectivity for ammonia synthesis while maintaining long-term stability.Herein the magnetic biochar(Fe-C)has been synthesized by a two-step mechanochemical route after a pyrolysis treatment(450,700,and 1000℃),which not only significantly decreases the particle size,but also exposes more oxygen-rich functional groups on the surface,promoting the adsorption of nitrate and water and accelerating electron transfer to convert it into ammonia.Results showed that the catalyst(Fe-C-700)has an impressive NH_(3)production rate of 3.5 mol·h^(−1)·gcat^(−1),high Faradaic efficiency of 88%,and current density of 0.37 A·cm^(−2)at 0.8 V vs.reversible hydrogen electrode(RHE).In-situ Fourier transform infrared spectroscopy(FTIR)is used to investigate the reaction intermediate and to monitor the reaction.The oxygen functionalities on the catalyst surface activate nitrate ions to form various intermediates(NO_(2),NO,NH_(2)OH,and NH_(2))and reduce the rate determining step energy barrier(*NO_(3)→*NO_(2)).This study presents a novel approach for the use of magnetic biochar as an electro-catalyst in NO_(3)RR and opens the road for solving environmental and energy challenges.
基金supported by the National Natural Science Foundation of China(Nos.52072152 and 51802126)the Jiangsu University Jinshan Professor Fund,the Jiangsu Specially-Appointed Professor Fund,Open Fund from Guangxi Key Laboratory of Electrochemical Energy Materials,Zhenjiang“Jinshan Talents”Project 2021,China PostDoctoral Science Foundation(No.2022M721372)+2 种基金“Doctor of Entrepreneurship and Innovation”in Jiangsu Province(No.JSSCBS20221197)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX22_3645)Key Research and Development Program of Zhenjiang City(No.CG2023004).
文摘Electrochemical carbon dioxide reduction reaction(CO_(2)RR)can produce value-added hydrocarbons from renewable electricity,providing a sustainable and promising approach to meet dual-carbon targets and alleviate the energy crisis.However,it is still challenging to improve the selectivity and stability of the products,especially the C^(2+) products.Here we propose to modulate the electronic structure of copper oxide(CuO)through lattice strain construction by zinc(Zn)doping to improve the selectivity of the catalyst to ethylene.Combined performance and in situ characterization analyses show that the compressive strain generated within the CuO lattice and the electronic structure modulation by Zn doping enhances the adsorption of the key intermediate*CO,thereby increasing the intrinsic activity of CO_(2)RR and inhibiting the hydrogen precipitation reaction.Among the best catalysts had significantly improved ethylene selectivity of 60.5%and partial current density of 500 mA·cm^(–2),and the highest C^(2+) Faraday efficiency of 71.47%.This paper provides a simple idea to study the modulation of CO_(2)RR properties by heteroatom doped and lattice strain.
基金supported by the National Key Research and Development Program of China(2020YFA0907800)the National Natural Science Foundation of China(31861133004,81872771)+2 种基金the Key Research Program of Frontier Sciences,CAS(ZDBS-LY-SM016)the Biological Resources Programme,Chinese Academy of Sciences(KFJBRP-009-005)the China Postdoctoral Science Foundation(YJ20200201,2020M680720,2022T150689)。
文摘Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative assessment of filamentous fungal promoters based on flow cytometry detection of the superfolder green fluorescent protein at single-cell resolution.Using this quantitative method,we acquired a library of 93 native promoter elements from Aspergillus nidulans in a high-throughput format.The strengths of identified promoters covered a 37-fold range by flow cytometry.P_(zipA) and P_(sltA)were identified as the strongest promoters,which were 2.9-and 1.5-fold higher than that of the commonly used constitutive promoter P_(gpdA).Thus,we applied P_(zipA)and P_(sltA)to activate the silent nonribosomal peptide synthetase gene Afpes1 from Aspergillus fumigatus in its native host and the heterologous host A.nidulans.The metabolic products of Afpes1 were identified as new cyclic tetrapeptide derivatives,namely,fumiganins A and B.Our method provides an innovative strategy for natural product discovery in fungi.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.81901876,81925019,81801817,and U1705281)Guangdong Basic and Applied Basic Research Foundation(No.2114050002159)+1 种基金Shenzhen Science and Technology Program(No.JCYJ20210324121801004)National College Student Innovation and Entrepreneurship Training Program(No.202012631001)。
文摘Corneal neovascularization(CNV) is one of the major factors for vision impairment and blindness worldwide. The current treatment for CNV focuses primarily on topical eyedrops of glucocorticoids,non-steroidal anti-inflammatory drugs, electro-coagulation and laser photo-coagulation. Unfortunately,coagulation-based treatment is restricted by corneal hemorrhage and iris atrophy. And drug treatments have limited therapeutic effects and a short duration of action. Nanoparticle-based drug delivery systems are widely applied due to their improved pharmacokinetics, optimized drug targeting and enhanced biocompatibility. In this article, we provide a comprehensive and systematic overview of the CNV nanodrug system, highlighting some of the recent advances in nanodrug design, preparation, and functional modification. Moreover, we discuss the challenges in the clinical translation and potential risks in CNV treatment. A greater effort is needed for the potential applications of nanotechnology in the field of ophthalmology.
基金This study was supported by the National Key R&D Program of China(2019YFE0101200)the Science and Technology Commission Shanghai Municipality,China(13JC1403400,18490740200)+1 种基金the Foreign Young Talent Program from the Ministry of Science and Technology,China(QN2022134003L)the Plan of Jiaxing Innovation and Elites Leading,China.
文摘Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed subjects.Induction of temporal heterogenicity in functions in addition to shape may extend the scope of 4D printing.Herein,we report a 4D printing approach using plant protein(zein)gel inspired by the amyloid fibrils formation mechanism.The printing of zein gel in a specialized layered-Carbopol supporting bath with different water concentrations in an ethanol-water mixture modulates hydrophobic and hydrogen bonding that causes temporal changes in functions.The part of the construct printed in a supporting bath with higher water content exhibits higher drug loading,faster drug release and degradation than those printed in the supporting bath with lower water content.Tri-segment conduit and butterfly-shaped construct with two asymmetrical wings are printed using this system to evaluate biomedical function as nerve conduit and drug delivery system.4D printed conduits are also effective as a drug-eluting urethral stent in the porcine model.Overall,this study extends the concept of 4D printing beyond shape transformation and presents an approach of fabricating specialized baths for 4D printing that can also be extended to other materials to obtain 4D printed medical devices with translational potential.
基金supported by Beijing Natural Science Foundation (5152018)the National Natural Science Foundation of China (31470178)Wen-Bing Yin is a scholar of "the 100 Talents Project" of CAS
文摘Laccases, multicopper oxidoreductases, are mainly produced in white-rot fungi and are considered as ideal green catalysts in industrial and biotechnological applications. However, the development of laccases is limited due to the slow growth of natural laccase producing strains and the low expression levels of laccases. In this study, we designed three regulation strategies for laccase gene expression in the model fungus Aspergillus nidulans. By introducing various promoters in front of the laccase gene pslcc from the white-rot fungus Pycnoporus sanguineus, we found that the laccase gene with the original promoter had effective expression in A. nidulans. Using the previously identified transcription factor RsmA regulatory mechanism, the aflR promoter was inserted into the pslcc expression vectors, and the laccase production was 15-fold higher in the strain overexpressing of RsmA compared to the control strain. To improve the laccase yield, the dipeptidyl-peptidase DppV, aspartic protease PepA and mannosyltransferase Mnn9 were successfully deleted in the A. nidulans host. The laccase activities were increased approximately 8-fold and 13-fold in the double deletions strains of Δmnn9ΔpepA and ΔdppVΔpepA over the control strains, respectively.Taken together, these results not only demonstrate an efficient system for heterologous protein production in the model fungus A.nidulans but also provide a general approach to applying regulatory methods to control gene expression.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research of China(Grant No.2019QZKK0208)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA20100304)+1 种基金the National Natural Science Foundation of China(Grant No.41790471)the National Basic Research Program of China(Grant No.2016YFA0602200)。
文摘In this study,the long-term trend of water vapor over the Tibetan Plateau(TP)in boreal summer is investigated by using observation and reanalysis data from 1979 to 2019.The historical experiment simulations of 19 models that participated in the Coupled Model Intercomparison Project phase 6(CMIP6)are evaluated,and the future variation tendency under four emission scenarios is projected.The results indicate that the water vapor content and the net water vapor budget over the TP show notable increasing trends,which are mainly manifested by a significant increase in the net water vapor import and a significant decrease in the water vapor export on the eastern boundary of the TP.This is mainly due to an anomalous anticyclone from Lake Baikal to the Mongolian Plateau.The CMIP6 multi-model ensemble can well simulate the variation characteristics of the TP net water vapor budget.The projection results indicate that by the end of the twenty-first century,the water vapor content,the net water vapor import and precipitation over the TP will increase.Under a high-emissions scenario and compared with the current period(1991–2014),these three variables will increase by 47.99%,59.77%and 18.59%in the long term(2081–2100),respectively.The significant enhancement of meridional water vapor transport over the northern TP may be the main reason for the increase in humidity over the TP.
文摘Mammalian central nervous system neurons show asymmetry during early brain development that defines the elaborate function of neural circuitry （Kriegstein and Noctor, 2004）. Many intracellular signaling pathways, which are important for the transition to the polarized state and the development of axons and dendrites, have been identified （Barnes and Polleux, 2009）. How these pathways are initiated during neuronal development in vivo remained elusive until Yi et al.
基金The authors are grateful for support from the Natural Science Fund of China(No.71661137003)the National Social Science Fund of China (No.16ZDA032)the Science Foundation of Ministry of Education of China(No.17JZD015).
文摘The neoclassical growth model predicts that capital account liberalization could potentially enhance economic performance;however, there is no consistent empirical evidence to support this positive association. Using a novel dataset of Chinese capital account openness, this paper demonstrates a positive relationship between capital account liberalization and aggregate economic performance. The difference-indifferences method is used to capture the causal effect of capital account liberalization on economic performance by taking advantage of variations in both external financial dependence and the progress of capital account openness. We investigate three channels that could strengthen this positive relationship using a firm-level dataset. We find that capital account liberalization could:(i) alleviate the degree of resource misallocation, and this effect is more significant in industries relying heavily on external finance and in regions with more favorable business environments;(ii) enhance firms' total factor productivity;and (iii) promote innovation. Our findings suggest that a strategy of gradual openness will leave some leeway not only for improvement in domestic markets but also to mitigate exposure to unfavorable global shocks.
基金supported by the National Natural Science Foundation of China (NSFC) [31471885,31772320]Fundamental Research Funds for the Central Universities [XDJK2016A005]the Research Innovation Program for College Graduates of Chongqing [CYS18092]
文摘The excess amounts of heavy metals are toxic to various physiological processes in plants.Plant metallothioneins(MTs)are low molecular weight,cysteine-rich metal-binding proteins that play important roles in the detoxification of heavy metal ions.In this study,we characterized Cs MT4,a plant type 4 MT gene identified in a complementary DNA(cDNA)library prepared from young cucumber(Cucumis sativus)fruit.Cs MT4encodes a 90 amino acid protein with a predicted molecular mass of 9.028 kD.CsMT4 contains 17 cysteine residues in three highly conserved cysteine-rich domains.In contrast to the structures of other MTs,the highly conserved amino acid pattern CxCxxxCxCxxCxC is present in the middle of CsMT4.Furthermore,CsMT4 was markedly induced in various tissues by various concentrations of Cd^(2+)and Zn^(2+)(>1.0 mmol·L^(-1)).Similar to AtMT4b function,heterologous expression of Cs MT4 in E.coli could also improved its tolerance to Cd^(2+)and led to increased uptake of Cd^(2+),and the rate of Cd^(2+)uptake was the highest in cells expressing a phytochelatin-like peptide.Our findings demonstrate that CsMT4 might be obviously induced by the metal stress in cucumber,and improves tolerance to Cd ions but not Zn ions when heterologously expressed in E.coli,and suggest that the composition and arrangement of N-terminal Cys-residues in MT4 are associated with their binding capacity and preference for different metal ions.
基金This study was supported in part by the National Key R&D Program of China(Nos.2018YFA0107301 and 2018YFA0107304)the National Natural Science Foundation of China(NSFC,Nos.81770894,81901876,81470602 and 81330022)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.20720190088 and 20720200019)the Medical and Health Key Project of Xiamen(No.3502Z20191106)the Program for New Century Excellent Talents in University,China(No.NCET-13-0502).
文摘Corneal neovascularization(CNV) can induce severe visual impairment and even blindness.Current treatments have limited efficacy and some undesirable side effects.Phototherapy(FT) is a modern medical technique in CNV treatment and worth further improvement.Nanotechnology has various advantages and nanoparticle-mediated drug delive ry also contributes to CNV elimination.Phototherapy combined with functional nanoparticles featuring photoacoustic imaging contrast properties can accomplish accurate and safe inhibition of CNV,thus is promising in clinical application.
文摘Uncertainty induced by the political environment affects investment risk, and thus affects investment decisions, which have a close relationship with economic development. This paper investigates the economic cost of political instability using the case study of the tense relationship across-Strait in China. We use a synthetic control method to better model the counterfactual analysis of this case study. The intense situation of the relations across-Strait has great influence on the economic development of Fujian province. Fujian province is the closest province in proximity to Taiwan and also possesses the greatest preferential policies for Taiwan Residents direct investment. The empirical results of this study reveal that during 2001-2008 Fujian province＇s average annual loss in GDP per capita was 682.54 yuan. In other words, GDP per capita in Fujian has declined about 12.1 percent annually during this period compared with GDP per capita as calculated by the synthetic control method.
