Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation det...Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation detection method for microwave only detects clouds and precipitation horizontally,without considering the three-dimensional distribution of clouds.Extending precipitation detection from 2D to 3D is expected to bring more useful information to the data assimilation without using the all-sky approach.In this study,the 3D precipitation detection method is adopted to assimilate Microwave Temperature Sounder-2(MWTS-Ⅱ)onboard the Fengyun-3D,which can dynamically detect the channels above precipitating clouds by considering the near-real-time cloud parameters.Cycling data assimilation and forecasting experiments for Typhoons Lekima(2019)and Mitag(2019)are carried out.Compared with the control experiment,the quantity of assimilated data with the 3D precipitation detection increases by approximately 23%.The quality of the additional MWTS-Ⅱradiance data is close to the clear-sky data.The case studies show that the average root-mean-square errors(RMSE)of prognostic variables are reduced by 1.7%in the upper troposphere,leading to an average reduction of4.53%in typhoon track forecasts.The detailed diagnoses of Typhoon Lekima(2019)further show that the additional MWTS-Ⅱradiances brought by the 3D precipitation detection facilitate portraying a more reasonable circulation situation,thus providing more precise structures.This paper preliminarily proves that 3D precipitation detection has potential added value for increasing satellite data utilization and improving typhoon forecasts.展开更多
Soil acidifications become one of the main causes restricting the sustainable development of agriculture and causing issues of agricultural product safety.In order to explore the effect of different acidification on s...Soil acidifications become one of the main causes restricting the sustainable development of agriculture and causing issues of agricultural product safety.In order to explore the effect of different acidification on soil cadmium(Cd)availability,soil pot culture and hydroponic(soil potting solution extraction)were applied,and non-invasive micro-test technique(NMT)was combined.Here three different soil acidification processes were simulated,including direct acidification by adding sulfuric acid(AP1),acid rain acidification(AP2)by adding artificial simulated acid rain and excessive fertilization acidification by adding(NH_(4))_(2)SO_(4)(AP3).The results showed that for direct acidification(AP1),DTPA-Cd concentration in field soils in Liaoning(S1)and Zhejiang(S2)increased by 0.167-0.217 mg/kg and 0.181-0.346 mg/kg,respectively,compared with control group.When soil pH decreased by 0.45 units in S1,the Cd content of rice stems,leaves and roots increased by 0.48 to 6.04 mg/kg and 2.58 to 12.84mg/kg,respectively,When the pH value of soil S1 and S2 decreased by 0.20 units,the average velocity of Cd^(2+)at 200μm increased by 10.03-33.11 pmol/cm~2/sec and 21.33-52.86pmol/cm^(2)/sec,respectively,and followed the order of AP3>AP2>AP1.In summary,different acidification measures would improve the effectiveness of Cd,under the same pH reduction condition,fertilization acidification increased Cd availability most significantly.展开更多
Soil salinity is known to improve cadmium(Cd)mobility,especially in arid soils.However,the mechanisms involved in how salt stress-associated metabolic profiles participate in mediating Cd transport in the soil-plant s...Soil salinity is known to improve cadmium(Cd)mobility,especially in arid soils.However,the mechanisms involved in how salt stress-associated metabolic profiles participate in mediating Cd transport in the soil-plant system remain poorly understood.This study was designed to investigate the effects of salinity-induced changes in soil metabolites on Cd bioavailability.Sodium salts in different combinations according to molar ratio(NaCl:Na_(2)SO_(4)=1:1;NaCl:Na_(2)SO_(4):NaHCO_(3)=1:2:1;NaCl:Na_(2)SO_(4):NaHCO_(3):Na_(2)CO_(3)=1:9:9:1;NaCl:Na_(2)SO_(4):NaHCO_(3):Na_(2)CO_(3)=1:1:1:1)were applied to the Cd-contaminated soils,which increased soil Cd availability by 22.36%and the Cd content in wheat grains by 36.61%,compared to the control.Salt stress resulted in soil metabolic reprogramming,which might explain the decreased growth of wheat plants and increased Cd transport from the soil into wheat tissues.For example,down-regulation of starch and sucrose metabolism reduced the production of sugars,which adversely affected growth;up-regulation of fatty acid metabolism allowed wheat plants to maintain a normal intracellular environment under saline conditions;up-regulation of the tricarboxylic acid(TCA)cycle was triggered,causing an increase in organic acid synthesis and the accumulation of organic acids,which facilitated the migration of soil Cd into wheat tissues.In summary,salt stress can facilitate Cd transport into wheat tissues by the direct effect of salt-based ions and the combined effect of altered soil physicochemical properties and soil metabolic profiles in Cd-contaminated soils.展开更多
Genomic reassortment is an important evolutionary mechanism for influenza viruses.In this process,the novel viruses acquire new characteristics by the exchange of the intact gene segments among multiple influenza viru...Genomic reassortment is an important evolutionary mechanism for influenza viruses.In this process,the novel viruses acquire new characteristics by the exchange of the intact gene segments among multiple influenza virus genomes,which may cause flu endemics and epidemics within or even across hosts.Due to the safety and ethical limitations of the experimental studies on influenza virus reassortment,numerous computational researches on the influenza virus reassortment have been done with the explosion of the influenza virus genomic data.A great amount of computational methods and bioinformatics databases were developed to facilitate the identification of influenza virus reassortments.In this review,we summarized the progress and challenge of the bioinformatics research on influenza virus reassortment,which can guide the researchers to investigate the influenza virus reassortment events reasonably and provide valuable insight to develop the related computational identification tools.展开更多
基金jointly sponsored by the National Key Research and Development Program of China(Grant Nos.2018YFC1506701 and 2017YFC1502102)the National Natural Science Foundation of China(Grant No.41675102)。
文摘Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation detection method for microwave only detects clouds and precipitation horizontally,without considering the three-dimensional distribution of clouds.Extending precipitation detection from 2D to 3D is expected to bring more useful information to the data assimilation without using the all-sky approach.In this study,the 3D precipitation detection method is adopted to assimilate Microwave Temperature Sounder-2(MWTS-Ⅱ)onboard the Fengyun-3D,which can dynamically detect the channels above precipitating clouds by considering the near-real-time cloud parameters.Cycling data assimilation and forecasting experiments for Typhoons Lekima(2019)and Mitag(2019)are carried out.Compared with the control experiment,the quantity of assimilated data with the 3D precipitation detection increases by approximately 23%.The quality of the additional MWTS-Ⅱradiance data is close to the clear-sky data.The case studies show that the average root-mean-square errors(RMSE)of prognostic variables are reduced by 1.7%in the upper troposphere,leading to an average reduction of4.53%in typhoon track forecasts.The detailed diagnoses of Typhoon Lekima(2019)further show that the additional MWTS-Ⅱradiances brought by the 3D precipitation detection facilitate portraying a more reasonable circulation situation,thus providing more precise structures.This paper preliminarily proves that 3D precipitation detection has potential added value for increasing satellite data utilization and improving typhoon forecasts.
基金supported by the National Natural Science Foundation of China(No.42177010)the Youth innovation of Chinese Academy of Agricultural Sciences(No.Y2023QC17)。
文摘Soil acidifications become one of the main causes restricting the sustainable development of agriculture and causing issues of agricultural product safety.In order to explore the effect of different acidification on soil cadmium(Cd)availability,soil pot culture and hydroponic(soil potting solution extraction)were applied,and non-invasive micro-test technique(NMT)was combined.Here three different soil acidification processes were simulated,including direct acidification by adding sulfuric acid(AP1),acid rain acidification(AP2)by adding artificial simulated acid rain and excessive fertilization acidification by adding(NH_(4))_(2)SO_(4)(AP3).The results showed that for direct acidification(AP1),DTPA-Cd concentration in field soils in Liaoning(S1)and Zhejiang(S2)increased by 0.167-0.217 mg/kg and 0.181-0.346 mg/kg,respectively,compared with control group.When soil pH decreased by 0.45 units in S1,the Cd content of rice stems,leaves and roots increased by 0.48 to 6.04 mg/kg and 2.58 to 12.84mg/kg,respectively,When the pH value of soil S1 and S2 decreased by 0.20 units,the average velocity of Cd^(2+)at 200μm increased by 10.03-33.11 pmol/cm~2/sec and 21.33-52.86pmol/cm^(2)/sec,respectively,and followed the order of AP3>AP2>AP1.In summary,different acidification measures would improve the effectiveness of Cd,under the same pH reduction condition,fertilization acidification increased Cd availability most significantly.
基金supported by the National Natural Science Foundation of China(Nos.42177010 and 41877387)Fundamental Research Funds for Central Non-profit Scientific Institution(No.1610132021008).
文摘Soil salinity is known to improve cadmium(Cd)mobility,especially in arid soils.However,the mechanisms involved in how salt stress-associated metabolic profiles participate in mediating Cd transport in the soil-plant system remain poorly understood.This study was designed to investigate the effects of salinity-induced changes in soil metabolites on Cd bioavailability.Sodium salts in different combinations according to molar ratio(NaCl:Na_(2)SO_(4)=1:1;NaCl:Na_(2)SO_(4):NaHCO_(3)=1:2:1;NaCl:Na_(2)SO_(4):NaHCO_(3):Na_(2)CO_(3)=1:9:9:1;NaCl:Na_(2)SO_(4):NaHCO_(3):Na_(2)CO_(3)=1:1:1:1)were applied to the Cd-contaminated soils,which increased soil Cd availability by 22.36%and the Cd content in wheat grains by 36.61%,compared to the control.Salt stress resulted in soil metabolic reprogramming,which might explain the decreased growth of wheat plants and increased Cd transport from the soil into wheat tissues.For example,down-regulation of starch and sucrose metabolism reduced the production of sugars,which adversely affected growth;up-regulation of fatty acid metabolism allowed wheat plants to maintain a normal intracellular environment under saline conditions;up-regulation of the tricarboxylic acid(TCA)cycle was triggered,causing an increase in organic acid synthesis and the accumulation of organic acids,which facilitated the migration of soil Cd into wheat tissues.In summary,salt stress can facilitate Cd transport into wheat tissues by the direct effect of salt-based ions and the combined effect of altered soil physicochemical properties and soil metabolic profiles in Cd-contaminated soils.
基金This work was supported by the National Natural Science Foundation of China(31801101 to X.D.,31671371,32070678 to T.J.)the CAMS Initiative for Innovative Medicine(CAMS-I2M,2016-I2M-1-005,2020-I2M-2-003 to T.J.)。
文摘Genomic reassortment is an important evolutionary mechanism for influenza viruses.In this process,the novel viruses acquire new characteristics by the exchange of the intact gene segments among multiple influenza virus genomes,which may cause flu endemics and epidemics within or even across hosts.Due to the safety and ethical limitations of the experimental studies on influenza virus reassortment,numerous computational researches on the influenza virus reassortment have been done with the explosion of the influenza virus genomic data.A great amount of computational methods and bioinformatics databases were developed to facilitate the identification of influenza virus reassortments.In this review,we summarized the progress and challenge of the bioinformatics research on influenza virus reassortment,which can guide the researchers to investigate the influenza virus reassortment events reasonably and provide valuable insight to develop the related computational identification tools.