Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable lan...Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade,with the aid of GIS technology.Conclusions of the research are summarized as follows：（1）the arable land had been continuously decreasing from 1996 to 2005,with a loss of 1,708,700 hm^2 and an average decrement of 170,900 hm^2 per year;（2）land for construction increased 1,373,700 hm^2 ,with an average increment of 153,200 hm^2 per year;（3）total area of encroachment on arable land for construction between 1996 and 2005 was 1,053,100 hm^2 ,accounting for 34.03%of the arable land loss in the same period,the percentages of which used for industrial land（INL）,transportation land（TRL）,rural construction land（RUL）and town construction land（TOL）are 45.03%,15.8%,15.47%and 11.5%,respectively;and（4）the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation＇s macroscopic land-use policies and development level of regional economy.The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures,rural urbanization and expansion of rural settlements in the eastern coastal area,and therefore were the primary driving forces of land-use conversion.展开更多
After entering the twenty-first century,biochar has become a focal point of multidisciplinary research because of its special characteristics,broad application,and promising development prospects.Basic and applied res...After entering the twenty-first century,biochar has become a focal point of multidisciplinary research because of its special characteristics,broad application,and promising development prospects.Basic and applied research on the application of biochar in the areas of agriculture,environment,and energy have increased dramatically in the face of food security,environmental pollution,and energy shortage.Although there are some disputes about biochar research,many studies have demonstrated the importance of biochar research from the perspective of scientific advancement and practical application.This paper briefly recalls the history of biochar application;introduces research progress on the basic characteristics of biochar and its associated production technologies;summarizes the research status and existing problems of biochar application in the areas of agriculture,environment,and energy;and analyzes the potential problems and development trends of biochar research in the future.展开更多
The screening of novel materials with good performance and the modelling of quantitative structureactivity relationships(QSARs),among other issues,are hot topics in the field of materials science.Traditional experimen...The screening of novel materials with good performance and the modelling of quantitative structureactivity relationships(QSARs),among other issues,are hot topics in the field of materials science.Traditional experiments and computational modelling often consume tremendous time and resources and are limited by their experimental conditions and theoretical foundations.Thus,it is imperative to develop a new method of accelerating the discovery and design process for novel materials.Recently,materials discovery and design using machine learning have been receiving increasing attention and have achieved great improvements in both time efficiency and prediction accuracy.In this review,we first outline the typical mode of and basic procedures for applying machine learning in materials science,and we classify and compare the main algorithms.Then,the current research status is reviewed with regard to applications of machine learning in material property prediction,in new materials discovery and for other purposes.Finally,we discuss problems related to machine learning in materials science,propose possible solutions,and forecast potential directions of future research.By directly combining computational studies with experiments,we hope to provide insight into the parameters that affect the properties of materials,thereby enabling more efficient and target-oriented research on materials discovery and design.展开更多
In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function m...In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function mutation into the Waxy gene in two widely cultivated elite japonica varieties. Our results show that mutations in the Waxy gene reduce AC and convert the rice into glutinous ones without affecting other desirable agronomic traits, offering an effective and easy strategy to improve glutinosity in elite varieties. Importantly, we successfully removed the transgenes from the progeny. Our study provides an example of generating improved crops with potential for commercialization, by editing a gene of interest directly in elite crop varieties.展开更多
Since December 2019,an epidemic caused by novel coronavirus (2019-nCoV) infection has occurred unexpectedly in China.As of 8 pm,31 January 2020,more than 20 pediatric cases have been reported in China.Of these cases,t...Since December 2019,an epidemic caused by novel coronavirus (2019-nCoV) infection has occurred unexpectedly in China.As of 8 pm,31 January 2020,more than 20 pediatric cases have been reported in China.Of these cases,ten patients were identified in Zhejiang Province,with an age of onset ranging from 112 days to 17 years.Following the latest National recommendations for diagnosis and treatment of pneumonia caused by 2019-nCo V (the 4th edition) and current status of clinical practice in Zhejiang Province,recommendations for the diagnosis and treatment of respiratory infection caused by 2019-nCoV for children were drafted by the National Clinical Research Center for Child Health,the National Children's Regional Medical Center,Children's Hospital,Zhejiang University School of Medicine to further standardize the protocol for diagnosis and treatment of respiratory infection in children caused by 2019-nCoV.展开更多
China has the world's largest and still growing wastewater sector and water market,thus its future development will have profound influence on the world.The high-speed development of China's wastewater sector ...China has the world's largest and still growing wastewater sector and water market,thus its future development will have profound influence on the world.The high-speed development of China's wastewater sector over the past 40 years has forged its global leading treatment capacity and innovation ability.However,many problems were left behind,including underdeveloped sewers and sludge disposal facilities,low sustainability of the treatment processes,questionable wastewater treatment plant(WWTP)effluent discharge standards,and lacking global thinking on harmonious development between wastewater management,human society and the nature.Addressing these challenges calls for fundamental changes in target design,policy and technologies.In this mini-review,we revisit the development history of China's municipal wastewater management and identify the remaining challenges.Also,we highlight the future needs of sustainable development and exploring China's own wastewater management path,and outlook the future from several aspects including targets of wastewater management,policies and technologies,especially the new concept WWTP.Furthermore,we envisage the establishment of new-generation WWTPs with the vision of turning WWTP from a site of pollutant removal into a plant of energy,water and fertilizer recovery and an integrated part urban ecology in China.展开更多
Based on decreasing the flexibility of the power grid through the integration of large-scale renewable energy,a multi-energy storage system architectural model and its coor-dination operational strategy with the same ...Based on decreasing the flexibility of the power grid through the integration of large-scale renewable energy,a multi-energy storage system architectural model and its coor-dination operational strategy with the same flexibility as in the pumped storage power station and battery energy storage system(BESS)are studied.According to the new energy fluctuation characteristics and the different peak valley parameters in the power grid,this paper proposes a electricity heat hydrogen multi-energy storage system(EHH-MESS)and its coordination and optimization operational model to reduce the curtailment of wind power and photovoltaic(PV)to the power grid and improve the flexibility of the power grid.Finally,this paper studied the simulation model of an energy storage optimization control strategy after the multi-energy storage system is connected to the distribution networks,and analyzed three operational modes of the multi-energy storage system.The simulation results show that the EHH-MESS proposed in this paper has a better power grid regulation flexibility and economy,and can be used to replace the battery energy storage system based on MATLAB.展开更多
The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterpris...The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with.展开更多
Current global agricultural production must feed over 7 billion people.However,productivity varies greatly across the globe and is under threat from both increased competitions for land and climate change and associat...Current global agricultural production must feed over 7 billion people.However,productivity varies greatly across the globe and is under threat from both increased competitions for land and climate change and associated environmental deterioration.Moreover,the increase in human population size and dietary changes are putting an ever greater burden on agriculture.The majority of this burden is met by the cultivation of a very small number of species,largely in locations that differ from their origin of domestication.Recent technological advances have raised the possibility of de novo domestication of wild plants as a viable solution for designing ideal crops while maintaining food security and a more sustainable lowinput agriculture.Here we discuss how the discovery of multiple key domestication genes alongside the development of technologies for accurate manipulation of several target genes simultaneously renders de novo domestication a route toward crops for the future.展开更多
From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).During those 20 yea...From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).During those 20 years,4407 new taxa of vascular plants were described from China,including 7 new families,132 new genera,3543 new species,68 new subspecies,497 new varieties and 160 new forms.Additionally,3562 new combinations and names at new rank and 306 new replacement names were also proposed.Among these various new names were 150 invalid names and 108 illegitimate names,including some that have not been resolved.Six hundred and forty three vascular plants were reported as new to China,while 2349 names were reduced to synonyms of 1406 taxa.The data show that the Chinese flora increased in size at the rate of about 200 taxa annually during those years.Despite the increased attention given to biodiversity in recent years,the evidence indicates that a large number of species in China have yet to be discovered.Further basic investigation of the Chinese flora is needed.Additionally,in the past two decades only 8.5%of the newly published species have been based on molecular evidence,but in the past five years such data have increased significantly,reaching about 20%.Molecular data will undoubtedly become increasingly significant in the discovery of new species in the coming years.Yunnan,Guangxi,Sichuan,Xizang and Taiwan were important sources of new discoveries,with more than 3300 new taxa and records from these five provinces.By area,Taiwan and Hainan,two islands in southern China,have the highest density of newly discovered species.Regional plant surveys are still needed,especially in areas in the southwest and on the southern islands.展开更多
Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2...Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2-bis(p-chlorophenyl)e- thane (DDD), hexachlorocyclohexane (HCH) and its isomers (α-,β-, γ-, and δ-HCH), hexachlorobenzene (HCB), endo- sulfan, dieldrin, and endrin were quantified to determine current levels of organochlorine pesticides, to assess the eco- toxicological potential, and to distin…展开更多
Chronic kidney disease(CKD) typically evolves over many years, with a long latent period when the disease is clinically silent and therefore diagnosis, evaluation and treatment is based mainly on biomarkers that asses...Chronic kidney disease(CKD) typically evolves over many years, with a long latent period when the disease is clinically silent and therefore diagnosis, evaluation and treatment is based mainly on biomarkers that assess kidney function. Glomerular filtration rate(GFR) remains the ideal marker of kidney function. Unfortunately measuring GFR is time consuming and therefore GFR is usually estimated from equations that take into account endogenous filtration markers like serum creatinine(SCr) and cystatin C(Cys C). Other biomarkers such as albuminuria may precede kidney function decline and have demonstrated to have strong associationswith disease progression and outcomes. New potential biomarkers have arisen with the promise of detecting kidney damage prior to the currently used markers. The aim of this review is to discuss the utility of the GFR estimating equations and biomarkers in CKD and the different clinical settings where these should be applied. The CKD-Epidemiology Collaboration equation performs better than the modification of diet in renal disease equation, especially at GFR above 60 m L/min per 1.73 m2. Equations combining Cys C and SCr perform better than the equations using either Cys C or SCr alone and are recommended in situations where CKD needs to be confirmed. Combining creatinine, Cys C and urine albumin to creatinine ratio improves risk stratification for kidney disease progression and mortality. Kidney injury molecule and neutrophil gelatinase-associated lipocalin are considered reasonable biomarkers in urine and plasma to determine severity and prognosis of CKD.展开更多
基金National Natural Science Foundation of China, No.40635029 No.40771014
文摘Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade,with the aid of GIS technology.Conclusions of the research are summarized as follows：（1）the arable land had been continuously decreasing from 1996 to 2005,with a loss of 1,708,700 hm^2 and an average decrement of 170,900 hm^2 per year;（2）land for construction increased 1,373,700 hm^2 ,with an average increment of 153,200 hm^2 per year;（3）total area of encroachment on arable land for construction between 1996 and 2005 was 1,053,100 hm^2 ,accounting for 34.03%of the arable land loss in the same period,the percentages of which used for industrial land（INL）,transportation land（TRL）,rural construction land（RUL）and town construction land（TOL）are 45.03%,15.8%,15.47%and 11.5%,respectively;and（4）the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation＇s macroscopic land-use policies and development level of regional economy.The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures,rural urbanization and expansion of rural settlements in the eastern coastal area,and therefore were the primary driving forces of land-use conversion.
基金supported by the Earmarked Fund for Modern Agro-industry Technology Research System,China(Project No.CARS-01-46)the National Key Research and Development Program,China(Project No.2017YFD0200800)+1 种基金the Innovative Talents Promotion Plan of Ministry of Science and Technology,China(No.2017RA2211)the Project of Promoting Talents in Liaoning Province,China(XLYC1802094).
文摘After entering the twenty-first century,biochar has become a focal point of multidisciplinary research because of its special characteristics,broad application,and promising development prospects.Basic and applied research on the application of biochar in the areas of agriculture,environment,and energy have increased dramatically in the face of food security,environmental pollution,and energy shortage.Although there are some disputes about biochar research,many studies have demonstrated the importance of biochar research from the perspective of scientific advancement and practical application.This paper briefly recalls the history of biochar application;introduces research progress on the basic characteristics of biochar and its associated production technologies;summarizes the research status and existing problems of biochar application in the areas of agriculture,environment,and energy;and analyzes the potential problems and development trends of biochar research in the future.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.U1630134,51622207 and 51372228)the National Key Research and Development Program of China(Grant Nos.2017YFB0701600 and 2017YFB0701500)+2 种基金the Shanghai Institute of Materials Genome from the Shanghai Municipal Science and Technology Commission(Grant No.14DZ2261200)the Shanghai Municipal Education Commission(Grant No.14ZZ099)the Natural Science Foundation of Shanghai(Grant No.16ZR1411200).
文摘The screening of novel materials with good performance and the modelling of quantitative structureactivity relationships(QSARs),among other issues,are hot topics in the field of materials science.Traditional experiments and computational modelling often consume tremendous time and resources and are limited by their experimental conditions and theoretical foundations.Thus,it is imperative to develop a new method of accelerating the discovery and design process for novel materials.Recently,materials discovery and design using machine learning have been receiving increasing attention and have achieved great improvements in both time efficiency and prediction accuracy.In this review,we first outline the typical mode of and basic procedures for applying machine learning in materials science,and we classify and compare the main algorithms.Then,the current research status is reviewed with regard to applications of machine learning in material property prediction,in new materials discovery and for other purposes.Finally,we discuss problems related to machine learning in materials science,propose possible solutions,and forecast potential directions of future research.By directly combining computational studies with experiments,we hope to provide insight into the parameters that affect the properties of materials,thereby enabling more efficient and target-oriented research on materials discovery and design.
基金supported by the Chinese Academy of SciencesUS NIH Grants R01GM070795 and R01GM059138(to J.K.Z.)the support of the International Postdoctoral Exchange Fellowship Program of China under grant 20140029
文摘In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function mutation into the Waxy gene in two widely cultivated elite japonica varieties. Our results show that mutations in the Waxy gene reduce AC and convert the rice into glutinous ones without affecting other desirable agronomic traits, offering an effective and easy strategy to improve glutinosity in elite varieties. Importantly, we successfully removed the transgenes from the progeny. Our study provides an example of generating improved crops with potential for commercialization, by editing a gene of interest directly in elite crop varieties.
文摘Since December 2019,an epidemic caused by novel coronavirus (2019-nCoV) infection has occurred unexpectedly in China.As of 8 pm,31 January 2020,more than 20 pediatric cases have been reported in China.Of these cases,ten patients were identified in Zhejiang Province,with an age of onset ranging from 112 days to 17 years.Following the latest National recommendations for diagnosis and treatment of pneumonia caused by 2019-nCo V (the 4th edition) and current status of clinical practice in Zhejiang Province,recommendations for the diagnosis and treatment of respiratory infection caused by 2019-nCoV for children were drafted by the National Clinical Research Center for Child Health,the National Children's Regional Medical Center,Children's Hospital,Zhejiang University School of Medicine to further standardize the protocol for diagnosis and treatment of respiratory infection in children caused by 2019-nCoV.
文摘China has the world's largest and still growing wastewater sector and water market,thus its future development will have profound influence on the world.The high-speed development of China's wastewater sector over the past 40 years has forged its global leading treatment capacity and innovation ability.However,many problems were left behind,including underdeveloped sewers and sludge disposal facilities,low sustainability of the treatment processes,questionable wastewater treatment plant(WWTP)effluent discharge standards,and lacking global thinking on harmonious development between wastewater management,human society and the nature.Addressing these challenges calls for fundamental changes in target design,policy and technologies.In this mini-review,we revisit the development history of China's municipal wastewater management and identify the remaining challenges.Also,we highlight the future needs of sustainable development and exploring China's own wastewater management path,and outlook the future from several aspects including targets of wastewater management,policies and technologies,especially the new concept WWTP.Furthermore,we envisage the establishment of new-generation WWTPs with the vision of turning WWTP from a site of pollutant removal into a plant of energy,water and fertilizer recovery and an integrated part urban ecology in China.
基金This project was supported by National Key Research and Development Plan(2017YFB0902100).
文摘Based on decreasing the flexibility of the power grid through the integration of large-scale renewable energy,a multi-energy storage system architectural model and its coor-dination operational strategy with the same flexibility as in the pumped storage power station and battery energy storage system(BESS)are studied.According to the new energy fluctuation characteristics and the different peak valley parameters in the power grid,this paper proposes a electricity heat hydrogen multi-energy storage system(EHH-MESS)and its coordination and optimization operational model to reduce the curtailment of wind power and photovoltaic(PV)to the power grid and improve the flexibility of the power grid.Finally,this paper studied the simulation model of an energy storage optimization control strategy after the multi-energy storage system is connected to the distribution networks,and analyzed three operational modes of the multi-energy storage system.The simulation results show that the EHH-MESS proposed in this paper has a better power grid regulation flexibility and economy,and can be used to replace the battery energy storage system based on MATLAB.
文摘The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with.
基金the Max Planck Society.J.Y.is supported by the National Key Research and Development Program of China(2016YFD0101003)the National Natural Science Foundation of China(31525017+1 种基金31730064)the Fundamental Research Funds for the Central Un iversities.
文摘Current global agricultural production must feed over 7 billion people.However,productivity varies greatly across the globe and is under threat from both increased competitions for land and climate change and associated environmental deterioration.Moreover,the increase in human population size and dietary changes are putting an ever greater burden on agriculture.The majority of this burden is met by the cultivation of a very small number of species,largely in locations that differ from their origin of domestication.Recent technological advances have raised the possibility of de novo domestication of wild plants as a viable solution for designing ideal crops while maintaining food security and a more sustainable lowinput agriculture.Here we discuss how the discovery of multiple key domestication genes alongside the development of technologies for accurate manipulation of several target genes simultaneously renders de novo domestication a route toward crops for the future.
基金This study was supported by the Special Fund for Scientific Research of Shanghai Landscaping&City Appearance Administrative Bureau,China(G182415)the National Specimen Information Infrastructure(2018 Special Funds),China and Shanghai Sailing Program,China(14YF1413800).
文摘From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).During those 20 years,4407 new taxa of vascular plants were described from China,including 7 new families,132 new genera,3543 new species,68 new subspecies,497 new varieties and 160 new forms.Additionally,3562 new combinations and names at new rank and 306 new replacement names were also proposed.Among these various new names were 150 invalid names and 108 illegitimate names,including some that have not been resolved.Six hundred and forty three vascular plants were reported as new to China,while 2349 names were reduced to synonyms of 1406 taxa.The data show that the Chinese flora increased in size at the rate of about 200 taxa annually during those years.Despite the increased attention given to biodiversity in recent years,the evidence indicates that a large number of species in China have yet to be discovered.Further basic investigation of the Chinese flora is needed.Additionally,in the past two decades only 8.5%of the newly published species have been based on molecular evidence,but in the past five years such data have increased significantly,reaching about 20%.Molecular data will undoubtedly become increasingly significant in the discovery of new species in the coming years.Yunnan,Guangxi,Sichuan,Xizang and Taiwan were important sources of new discoveries,with more than 3300 new taxa and records from these five provinces.By area,Taiwan and Hainan,two islands in southern China,have the highest density of newly discovered species.Regional plant surveys are still needed,especially in areas in the southwest and on the southern islands.
基金1Project supported by the National Key Basic Research Support Foundation (NKBRSF) of China (No. 2002CB410805)and the Outstanding Youth Fund of National Natural Science Foundation of China (No. 40325001).
文摘Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2-bis(p-chlorophenyl)e- thane (DDD), hexachlorocyclohexane (HCH) and its isomers (α-,β-, γ-, and δ-HCH), hexachlorobenzene (HCB), endo- sulfan, dieldrin, and endrin were quantified to determine current levels of organochlorine pesticides, to assess the eco- toxicological potential, and to distin…
文摘Chronic kidney disease(CKD) typically evolves over many years, with a long latent period when the disease is clinically silent and therefore diagnosis, evaluation and treatment is based mainly on biomarkers that assess kidney function. Glomerular filtration rate(GFR) remains the ideal marker of kidney function. Unfortunately measuring GFR is time consuming and therefore GFR is usually estimated from equations that take into account endogenous filtration markers like serum creatinine(SCr) and cystatin C(Cys C). Other biomarkers such as albuminuria may precede kidney function decline and have demonstrated to have strong associationswith disease progression and outcomes. New potential biomarkers have arisen with the promise of detecting kidney damage prior to the currently used markers. The aim of this review is to discuss the utility of the GFR estimating equations and biomarkers in CKD and the different clinical settings where these should be applied. The CKD-Epidemiology Collaboration equation performs better than the modification of diet in renal disease equation, especially at GFR above 60 m L/min per 1.73 m2. Equations combining Cys C and SCr perform better than the equations using either Cys C or SCr alone and are recommended in situations where CKD needs to be confirmed. Combining creatinine, Cys C and urine albumin to creatinine ratio improves risk stratification for kidney disease progression and mortality. Kidney injury molecule and neutrophil gelatinase-associated lipocalin are considered reasonable biomarkers in urine and plasma to determine severity and prognosis of CKD.
