China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the ...China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.展开更多
The field of two-dimensional topological semimetals,which emerged at the intersection of two-dimensional materials and topological materials,has been rapidly developing in recent years.In this article,we briefly revie...The field of two-dimensional topological semimetals,which emerged at the intersection of two-dimensional materials and topological materials,has been rapidly developing in recent years.In this article,we briefly review the progress in this field.Our focus is on the basic concepts and notions,in order to convey a coherent overview of the field.Some material examples are discussed to illustrate the concepts.We discuss the outstanding problems in the field that need to be addressed in future research.展开更多
This paper demonstrates the implementation of flipped classroom in a private university and explicitly interprets the three major resisting forces that undermine the application of flipped classroom in college English...This paper demonstrates the implementation of flipped classroom in a private university and explicitly interprets the three major resisting forces that undermine the application of flipped classroom in college English teaching.Based on in-depth analysis of voices from different stakeholders,it is illustrated that administrators in the focal institution lack a clear mission of external adaptation and should be more aware of hearing different voices instead of forcing the policy.As for teachers,they are used to traditional teaching delivery and fear for technology challenge and the possibility of being substituted by technology,moreover,they do not have the initiative to make innovation in tech-based teaching approaches.In terms of students,due to their lack of independent learning ability and their dependence on teacher-centered classroom context,it is challenging to change their awareness and accept the flipped classroom.Based on the situation,it is suggested in the paper that stakeholders should adapt their mindset to the external changes,and leaders in the school need to model the way of the flipped classroom and inspire a shared vision so that it creates psychological safety for its members to try new things.展开更多
Organizations are facing unprecedented challenges in the 21st century and OD plays a significant role in creating effective responses to these changes.Not only has it been applied in the USA but gains popularity in dy...Organizations are facing unprecedented challenges in the 21st century and OD plays a significant role in creating effective responses to these changes.Not only has it been applied in the USA but gains popularity in dynamic Asian region under the megatrend of globalization and information technology.This paper gains insight from Asia Organization Development(OD)Network Summit and discusses future potential application of OD to educational systems.展开更多
In this work, the piezotronic effect is investigated for the first time in external electric fields ranging from 0 V·cm-I to 2,000 V·cm-1 by using n-type ZnO nanowires supported by a flexible substrate. In t...In this work, the piezotronic effect is investigated for the first time in external electric fields ranging from 0 V·cm-I to 2,000 V·cm-1 by using n-type ZnO nanowires supported by a flexible substrate. In the presence of an external electric field, the Schottky barrier height （SBH） is lowered by the image force, allowing more free carriers to pass through the metal-semiconductor junction and enhancing the screening effect on positive piezoelectric polarization charges. As the strength of the external electric field increases, the piezotronic effect is significantly suppressed and the metal-semiconductor contact finally exhibits Ohmic behavior. The experimental results show that devices can be classified into three groups, corresponding to low, moderate, and high carrier densities of the nanowires used. This work not only helps us to explicate the basic physical mechanism of the piezotronic effect in a harsh environment in an electric field but also provides guidelines for future design and fabrication of piezotronic devices.展开更多
Dear Editor To date,tens of millions of people have been infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),causing the outbreak of the respiratory disease named the coronavirus disease 2019(COV...Dear Editor To date,tens of millions of people have been infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),causing the outbreak of the respiratory disease named the coronavirus disease 2019(COVID-19).As a newly emerged member of the coronavirus family,SARS-CoV-2 is an enveloped positive-strand RNA virus,which has probably the largest genome(approximately 30 kb)among all RNA viruses.The nucleocapsid(N)protein of SARS-CoV-2 is mainly responsible for recognizing and wrapping viral RNA into helically symmetric structures(Malik,2020).展开更多
The global spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)requires an urgent need to find effective therapeutics for the treatment of coronavirus disease 2019(COVID-19).In this study,we developed...The global spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)requires an urgent need to find effective therapeutics for the treatment of coronavirus disease 2019(COVID-19).In this study,we developed an integrative drug repositioning framework,which fully takes advantage of machine learning and statistical analysis approaches to systematically integrate and mine large-scale knowledge graph,literature and transcriptome data to discover the potential drug candidates against SARS-CoV-2.Our in silico screening followed by wet-lab validation indicated that a poly-ADP-ribose polymerase 1(PARP1)inhibitor,CVL218,currently in Phase I clinical trial,may be repurposed to treat COVID-19.Our in vitro assays revealed that CVL218 can exhibit effective inhibitory activity against SARS-CoV-2 replication without obvious cytopathic effect.In addition,we showed that CVL218 can interact with the nucleocapsid(N)protein of SARS-CoV-2 and is able to suppress the LPS-induced production of several inflammatory cytokines that are highly relevant to the prevention of immunopathology induced by SARS-CoV-2 infection.展开更多
This paper offers the first empirical evidence of the impact of COVID-19 on dietary diversity among children and adolescents in urban and rural families by using panel data collected in 2019(before COVID-19)and 2020(d...This paper offers the first empirical evidence of the impact of COVID-19 on dietary diversity among children and adolescents in urban and rural families by using panel data collected in 2019(before COVID-19)and 2020(during COVID-19)in northern China.Our study uses panel data from 2,201 primary school students and 1,341 junior high-school students to apply the difference in differences(DID)method to estimate the impact of COVID-19 on dietary diversity among students in urban and rural families.We found that the dietary diversity score(DDS)of rural students decreased by 0.295 points(p<0.01)compared with that of urban students during COVID-19.Specifically,COVID-19 significantly reduced the frequency of rural students'consumption of vegetables by 1.8 percent,protein-rich foods such as soybean products and nuts by 6.0 percent,meats by 4.0 percent,aquatic products by 6.7 percent,and eggs by 5.3 percent,compared with urban students.Further,COVID-19 had a significant negative effect on the dietary diversity of students from low-and middle-income groups,with the DDS of the low-income group decreasing by 0.31 points(p<0.01)and that of the middle-income group by 0.12 points(p<0.1).展开更多
基金The authors acknowledge the financial support received from the National Natural Science Foundation of China(72061147002).
文摘China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.
基金supported by the Singapore Ministry of Education AcRF Tier 2(Grant No.MOE2019-T2-1-101).
文摘The field of two-dimensional topological semimetals,which emerged at the intersection of two-dimensional materials and topological materials,has been rapidly developing in recent years.In this article,we briefly review the progress in this field.Our focus is on the basic concepts and notions,in order to convey a coherent overview of the field.Some material examples are discussed to illustrate the concepts.We discuss the outstanding problems in the field that need to be addressed in future research.
文摘This paper demonstrates the implementation of flipped classroom in a private university and explicitly interprets the three major resisting forces that undermine the application of flipped classroom in college English teaching.Based on in-depth analysis of voices from different stakeholders,it is illustrated that administrators in the focal institution lack a clear mission of external adaptation and should be more aware of hearing different voices instead of forcing the policy.As for teachers,they are used to traditional teaching delivery and fear for technology challenge and the possibility of being substituted by technology,moreover,they do not have the initiative to make innovation in tech-based teaching approaches.In terms of students,due to their lack of independent learning ability and their dependence on teacher-centered classroom context,it is challenging to change their awareness and accept the flipped classroom.Based on the situation,it is suggested in the paper that stakeholders should adapt their mindset to the external changes,and leaders in the school need to model the way of the flipped classroom and inspire a shared vision so that it creates psychological safety for its members to try new things.
文摘Organizations are facing unprecedented challenges in the 21st century and OD plays a significant role in creating effective responses to these changes.Not only has it been applied in the USA but gains popularity in dynamic Asian region under the megatrend of globalization and information technology.This paper gains insight from Asia Organization Development(OD)Network Summit and discusses future potential application of OD to educational systems.
文摘In this work, the piezotronic effect is investigated for the first time in external electric fields ranging from 0 V·cm-I to 2,000 V·cm-1 by using n-type ZnO nanowires supported by a flexible substrate. In the presence of an external electric field, the Schottky barrier height （SBH） is lowered by the image force, allowing more free carriers to pass through the metal-semiconductor junction and enhancing the screening effect on positive piezoelectric polarization charges. As the strength of the external electric field increases, the piezotronic effect is significantly suppressed and the metal-semiconductor contact finally exhibits Ohmic behavior. The experimental results show that devices can be classified into three groups, corresponding to low, moderate, and high carrier densities of the nanowires used. This work not only helps us to explicate the basic physical mechanism of the piezotronic effect in a harsh environment in an electric field but also provides guidelines for future design and fabrication of piezotronic devices.
基金This work was supported in part by the National Natural Science Foundation of China(61872216 and 81630103 to JZ,31900862 to DZ,31871443 to PL)the National Key R&D Program(2019YFA0508403 to PL,2020YFA0803300 to HL)the Turing Al Institute of Nanjing and the Zhongguancun Haihua Institute for Frontier Information Technology.
文摘Dear Editor To date,tens of millions of people have been infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),causing the outbreak of the respiratory disease named the coronavirus disease 2019(COVID-19).As a newly emerged member of the coronavirus family,SARS-CoV-2 is an enveloped positive-strand RNA virus,which has probably the largest genome(approximately 30 kb)among all RNA viruses.The nucleocapsid(N)protein of SARS-CoV-2 is mainly responsible for recognizing and wrapping viral RNA into helically symmetric structures(Malik,2020).
基金This work was supported in part by the National Natural Science Foundation of China(61872216,81630103,31900862,31725014)Jiangsu Provincial Emergency Project on Prevention and Control of COVID-19 Epidemic(BE2020601)+2 种基金the Nation Science and Technology Major Projects for Major New Drugs Innovation and Development(2018ZX09711003-004-002,2019ZX09301010)Pudong New Area Science and Technology Development Foundation(PKX2019-S08)the Turing Al Institute of Nanjing,and the Zhongguancun Haihua Institute for Frontier Information Technology.
文摘The global spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)requires an urgent need to find effective therapeutics for the treatment of coronavirus disease 2019(COVID-19).In this study,we developed an integrative drug repositioning framework,which fully takes advantage of machine learning and statistical analysis approaches to systematically integrate and mine large-scale knowledge graph,literature and transcriptome data to discover the potential drug candidates against SARS-CoV-2.Our in silico screening followed by wet-lab validation indicated that a poly-ADP-ribose polymerase 1(PARP1)inhibitor,CVL218,currently in Phase I clinical trial,may be repurposed to treat COVID-19.Our in vitro assays revealed that CVL218 can exhibit effective inhibitory activity against SARS-CoV-2 replication without obvious cytopathic effect.In addition,we showed that CVL218 can interact with the nucleocapsid(N)protein of SARS-CoV-2 and is able to suppress the LPS-induced production of several inflammatory cytokines that are highly relevant to the prevention of immunopathology induced by SARS-CoV-2 infection.
文摘This paper offers the first empirical evidence of the impact of COVID-19 on dietary diversity among children and adolescents in urban and rural families by using panel data collected in 2019(before COVID-19)and 2020(during COVID-19)in northern China.Our study uses panel data from 2,201 primary school students and 1,341 junior high-school students to apply the difference in differences(DID)method to estimate the impact of COVID-19 on dietary diversity among students in urban and rural families.We found that the dietary diversity score(DDS)of rural students decreased by 0.295 points(p<0.01)compared with that of urban students during COVID-19.Specifically,COVID-19 significantly reduced the frequency of rural students'consumption of vegetables by 1.8 percent,protein-rich foods such as soybean products and nuts by 6.0 percent,meats by 4.0 percent,aquatic products by 6.7 percent,and eggs by 5.3 percent,compared with urban students.Further,COVID-19 had a significant negative effect on the dietary diversity of students from low-and middle-income groups,with the DDS of the low-income group decreasing by 0.31 points(p<0.01)and that of the middle-income group by 0.12 points(p<0.1).
