The coastal areas of the lower reaches of Oujiang River Basin are rich in groundwater resources.However,the unsustainable exploitation and utilization of groundwater have led to significant changes in the groundwater ...The coastal areas of the lower reaches of Oujiang River Basin are rich in groundwater resources.However,the unsustainable exploitation and utilization of groundwater have led to significant changes in the groundwater environment.Understanding the characteristics and genesis of groundwater salinization is crucial for preventing its deterioration and ensuring sustainable utilization.In this study,a comprehensive approach combining the ion ratio method,mineral saturation index method and multivariate statistical analysis was employed to investigate the hydrochemical characteristics and main controlling factors in the study area.The findings reveal that:(1)Groundwater samples in study area exhibit a neutral to slightly alkaline pH.The predominant chemical types of unconfined water are HCO_(3)-Ca·Na,HCO_(3)·Cl-Na·Ca and HCO_(3)·SO_(4)-Ca·Na,while confined water mainly exhibits Cl·HCO_(3)-Na and Cl-Na types.(2)Salinity coefficients indicate an increase in salinity from unconfined to confined water.TDS,Na^(+)and Cl^(–)concentrations show an increasing trend from mountainous to coastal areas in unconfined water,while confined water displays variability in TDS,Na^(+)and Cl^(–)concentrations.(3)Groundwater salinity is mainly influenced by water-rock interactions,including the dissolution of halite and gypsum,cation exchange,and seawater intrusion etc.Additionally,human activities and carbonate dissolution contribute to salinity in unconfined water.Seawater intrusion is identified as the primary factor leading to higher salinity in confined water compared to unconfined water,with increasing cation exchange and seawater interaction observed from unconfined to confined water.展开更多
Brassica napus,commonly known as rapeseed or canola,is a major oil crop contributing over 13%to the stable supply of edible vegetable oil worldwide.Identification and understanding the gene functions in the B.napus ge...Brassica napus,commonly known as rapeseed or canola,is a major oil crop contributing over 13%to the stable supply of edible vegetable oil worldwide.Identification and understanding the gene functions in the B.napus genome is crucial for genomic breeding.A group of genes controlling agronomic traits have been successfully cloned through functional genomics studies in B.napus.In this review,we present an overview of the progress made in the functional genomics of B.napus,including the availability of germplasm resources,omics databases and cloned functional genes.Based on the current progress,we also highlight the main challenges and perspectives in this field.The advances in the functional genomics of B.napus contribute to a better understanding of the genetic basis underlying the complex agronomic traits in B.napus and will expedite the breeding of high quality,high resistance and high yield in B.napus varieties.展开更多
Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcome...Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China. Methods: All infants admitted to 26 NICUs with a birth weight (BW) 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results: A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions: Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.展开更多
The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the c...The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.展开更多
α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis.Herein,we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH_(4)HCO_(3)as the ammonia ...α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis.Herein,we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH_(4)HCO_(3)as the ammonia source,enabling the highly efficient and regioselective synthesis of linearα,β-unsaturated primary amides.Various aromatic and aliphatic alkynes are transformed into the desired linearα,β-unsaturated primary amides in good to excellent yields.Further studies show that using NH_(4)HCO_(3)as the ammonia source is key to obtain good yields and selectivity.The utility of this route is demonstrated with the synthesis of linearα,β-unsaturated amides including vanilloid receptor-1 antagonist TRPV-1.展开更多
We present a phosphonium-containing catalyst generated in situ from phosphine and tert-butyl acrylate that serves as an unusual Lewis base catalyst.It was applied for the promotion of a remote 1,6-cyanation reaction o...We present a phosphonium-containing catalyst generated in situ from phosphine and tert-butyl acrylate that serves as an unusual Lewis base catalyst.It was applied for the promotion of a remote 1,6-cyanation reaction of p-quinone methides and fuchsones employing trimethylsilyl cyanide as the cyanide source.A diverse range ofα-diaryl andα-triaryl acetonitriles was obtained in high yields under mild reaction conditions with low catalyst loading(5 mol%).The practicality and utility of this protocol were demonstrated via the gram-scale preparation and facile elaboration of products.Mechanistic investigations(in situ NMR and ESI-MS analysis)were employed to characterize the active zwitterionic phosphonium intermediate,which was the“true”active catalyst.展开更多
基金supported by investigation project of China Geological Survey(DD20230507).
文摘The coastal areas of the lower reaches of Oujiang River Basin are rich in groundwater resources.However,the unsustainable exploitation and utilization of groundwater have led to significant changes in the groundwater environment.Understanding the characteristics and genesis of groundwater salinization is crucial for preventing its deterioration and ensuring sustainable utilization.In this study,a comprehensive approach combining the ion ratio method,mineral saturation index method and multivariate statistical analysis was employed to investigate the hydrochemical characteristics and main controlling factors in the study area.The findings reveal that:(1)Groundwater samples in study area exhibit a neutral to slightly alkaline pH.The predominant chemical types of unconfined water are HCO_(3)-Ca·Na,HCO_(3)·Cl-Na·Ca and HCO_(3)·SO_(4)-Ca·Na,while confined water mainly exhibits Cl·HCO_(3)-Na and Cl-Na types.(2)Salinity coefficients indicate an increase in salinity from unconfined to confined water.TDS,Na^(+)and Cl^(–)concentrations show an increasing trend from mountainous to coastal areas in unconfined water,while confined water displays variability in TDS,Na^(+)and Cl^(–)concentrations.(3)Groundwater salinity is mainly influenced by water-rock interactions,including the dissolution of halite and gypsum,cation exchange,and seawater intrusion etc.Additionally,human activities and carbonate dissolution contribute to salinity in unconfined water.Seawater intrusion is identified as the primary factor leading to higher salinity in confined water compared to unconfined water,with increasing cation exchange and seawater interaction observed from unconfined to confined water.
基金supported by grants from the National Science Fund for Distinguished Young Scholars(32225037)Hubei Hongshan Laboratory(2021HSZD004)+1 种基金HZAU-AGIS Cooperation Fund(SZYJY2022008)Higher Education Discipline Innovation Project(B20051)。
文摘Brassica napus,commonly known as rapeseed or canola,is a major oil crop contributing over 13%to the stable supply of edible vegetable oil worldwide.Identification and understanding the gene functions in the B.napus genome is crucial for genomic breeding.A group of genes controlling agronomic traits have been successfully cloned through functional genomics studies in B.napus.In this review,we present an overview of the progress made in the functional genomics of B.napus,including the availability of germplasm resources,omics databases and cloned functional genes.Based on the current progress,we also highlight the main challenges and perspectives in this field.The advances in the functional genomics of B.napus contribute to a better understanding of the genetic basis underlying the complex agronomic traits in B.napus and will expedite the breeding of high quality,high resistance and high yield in B.napus varieties.
文摘Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China. Methods: All infants admitted to 26 NICUs with a birth weight (BW) 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results: A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions: Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.
基金supported by the National Natural Science Foundation of China (No.21207034, 21172064)the Provincial Natural Science Foundation of Hunan (No.10JJ2006)the Key Scientific Research Fund of Hunan Provincial Education Department (No.10A022)
文摘The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.
基金financial supports from the National Natural Science Foundation of China(Nos.21772035,22022204,22072167,21202206)Natural Science Foundation of Hunan Province(Nos.2021JJ40147)。
文摘α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis.Herein,we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH_(4)HCO_(3)as the ammonia source,enabling the highly efficient and regioselective synthesis of linearα,β-unsaturated primary amides.Various aromatic and aliphatic alkynes are transformed into the desired linearα,β-unsaturated primary amides in good to excellent yields.Further studies show that using NH_(4)HCO_(3)as the ammonia source is key to obtain good yields and selectivity.The utility of this route is demonstrated with the synthesis of linearα,β-unsaturated amides including vanilloid receptor-1 antagonist TRPV-1.
基金support was provided by the National Natural Science Foundation of China(21971165,21921002,21772035,22101189)National Key R&D Program of China(2018YFA0903500)National Natural Science Foundation of Hunan(2021JJ40150).
文摘We present a phosphonium-containing catalyst generated in situ from phosphine and tert-butyl acrylate that serves as an unusual Lewis base catalyst.It was applied for the promotion of a remote 1,6-cyanation reaction of p-quinone methides and fuchsones employing trimethylsilyl cyanide as the cyanide source.A diverse range ofα-diaryl andα-triaryl acetonitriles was obtained in high yields under mild reaction conditions with low catalyst loading(5 mol%).The practicality and utility of this protocol were demonstrated via the gram-scale preparation and facile elaboration of products.Mechanistic investigations(in situ NMR and ESI-MS analysis)were employed to characterize the active zwitterionic phosphonium intermediate,which was the“true”active catalyst.