Recently developed CRISPR-mediated base editors,which enable the generation of num erous nucleotide changes in target genomic regions,have been widely adopted for gene correction and generation of crop germ plasms con...Recently developed CRISPR-mediated base editors,which enable the generation of num erous nucleotide changes in target genomic regions,have been widely adopted for gene correction and generation of crop germ plasms containing im portant gain-of-function genetic variations.How ever,to engineer target genes with unknown functional SNPs remains challenging.To address this issue,we present here abase-e diting-mediated gene evolution(BEMGE)m ethod,employing both Cas9n-based cytosine and adenine base editors as well as a single-guide RNA(sgRNA)library tiling the full-length coding region,for developing novel rice germ plasm swith mutations in any endogenous gene.To this end,OsALS1 was artificially evolved in rice cells using BEMGE through both Agrobacterium-mediated and particle-bom bardment-mediated transform ation.Four different types of amino acid substitutions in the evolved OsALS1,derived from two sites that have never been targeted by natural or human selection during rice dom estication,were identified,conferring varying levels of tolerance to the herbicide bispyribac-sodium.Furtherm ore,the P171F substitution identified in a strong OsALS1 allele was quickly introduced into the commercial rice cultivar Nangeng 46 through precise base editing w ith the corresponding base editor and sgRNA.Collectively,these data indicate great potential of BEMGE in creating important genetic variants of target genes for crop improvement.展开更多
Soil acidification is an important process in land degradation around the world as well as in China.Acidification of Alfisols was investigated in the tea gardens with various years of tea cultivation in the eastern Ch...Soil acidification is an important process in land degradation around the world as well as in China.Acidification of Alfisols was investigated in the tea gardens with various years of tea cultivation in the eastern China.Cultivation of tea plants caused soil acidification and soil acidity increased with the increase of tea cultivation period.Soil pH of composite samples from cultivated layers decreased by 1.37,1.62 and 1.85,respectively,after 13,34 and 54 years of tea plantation,as compared to the surface soil obtained from the unused land.Soil acidification rates at early stages of tea cultivation were found to be higher than those at the later stages.The acidification rate for the period of 0-13 years was as high as 4.40 kmol H + ha ?1 year ?1 for the cultivated layer samples.Soil acidification induced the decrease of soil exchangeable base cations and base cation saturation and thus increased the soil exchangeable acidity.Soil acidification also caused the decrease of soil cation exchange capacity,especially for the 54-year-old tea garden.Soil acidification induced by tea plantation also led to the increase of soil exchangeable Al and soluble Al,which was responsible for the Al toxicity to plants.展开更多
The liming potential of some crop residues and their biochars on an acid Ultisol was investigated using incubation experiments. Rice hulls showed greater liming potential than rice hull biochar, while soybean and pea ...The liming potential of some crop residues and their biochars on an acid Ultisol was investigated using incubation experiments. Rice hulls showed greater liming potential than rice hull biochar, while soybean and pea straws had less liming potential than their biochars. Due to their higher alkalinity, biochars from legume materials increased soil pH much compared to biochars from non-legume materials. The alkalinity of biochars was a key factor affecting their liming potential, and the greater alkalinity of biochars led to greater reductions in soil acidity. The incorporation of biochars decreased soil exchangeable acidity and increased soil exchangeable base cations and base saturation, thus improving soil fertility.展开更多
采用碱活化过一硫酸盐(peroxymonosulfate,PMS)对环丙沙星(ciprofloxacin,CIP)的去除进行了系统地研究.结果表明,碱活化PMS体系能够高效地去除CIP.通过自由基捕获实验确定了单线态氧(~1O_2)和超氧自由基(O_2^-·)是反应体系中的主...采用碱活化过一硫酸盐(peroxymonosulfate,PMS)对环丙沙星(ciprofloxacin,CIP)的去除进行了系统地研究.结果表明,碱活化PMS体系能够高效地去除CIP.通过自由基捕获实验确定了单线态氧(~1O_2)和超氧自由基(O_2^-·)是反应体系中的主要活性物种.NaOH浓度、PMS浓度、反应温度和共存阴离子等对CIP在碱活化PMS体系中的去除均有一定影响.随着NaOH和PMS浓度的增加,CIP的降解均呈现出先增加后降低的趋势.提高反应温度能够加大CIP的反应速率,经过阿伦尼乌斯方程拟合得到的反应活化能为5.09 k J·mol^(-1).不同的阴离子对CIP的去除呈现不同的影响:Cl^-、SO_4^(2-)和NO_3^-对CIP的降解没有呈现明显的作用,H_2PO_4^(2-)能够有效地抑制环丙沙星的去除,而CO_3^(2-)极大地促进了反应进程.通过UPLC-MS/MS可检测到10种降解产物,CIP分子结构中的哌嗪环易于受到活性物种的攻击.展开更多
The article studies the theoretical basis for the hypothesis of brain intestine connection from 3 perspectives,suggesting the discovery of brain gut peptide make the hypothesis possible.And the neuro gastroenterology ...The article studies the theoretical basis for the hypothesis of brain intestine connection from 3 perspectives,suggesting the discovery of brain gut peptide make the hypothesis possible.And the neuro gastroenterology offers another foundation.The clinical report on the relationship of brain intestinal disease is the base of this hypothesis. This hypothesis is vital to traditional Chinese medicine and treatment of brain intestinal disease.展开更多
The fuzzy control algorithms used commonly at present are all regarded as some interpolation functions, which is in essence equivalent to discrete response functions to be fitted. This means that fuzzy control method ...The fuzzy control algorithms used commonly at present are all regarded as some interpolation functions, which is in essence equivalent to discrete response functions to be fitted. This means that fuzzy control method is similar to finite element method in mathematical physics, which is a kind of direct manner or numerical method in control systems.展开更多
Information on the Internet is fragmented and presented in different data sources, which makes automatic knowledge harvesting and understanding formidable for ma- chines, and even for humans. Knowledge graphs have be-...Information on the Internet is fragmented and presented in different data sources, which makes automatic knowledge harvesting and understanding formidable for ma- chines, and even for humans. Knowledge graphs have be- come prevalent in both of industry and academic circles these years, to be one of the most efficient and effective knowledge integration approaches. Techniques for knowledge graph construction can mine information from either structured, semi-structured, or even unstructured data sources, and fi- nally integrate the information into knowledge, represented in a graph. Furthermore, knowledge graph is able to organize information in an easy-to-maintain, easy-to-understand and easy-to-use manner. In this paper, we give a summarization of techniques for constructing knowledge graphs. We review the existing knowledge graph systems developed by both academia and industry. We discuss in detail about the process of building knowledge graphs, and survey state-of-the-art techniques for automatic knowledge graph checking and expansion via log- ical inferring and reasoning. We also review the issues of graph data management by introducing the knowledge data models and graph databases, especially from a NoSQL point of view. Finally, we overview current knowledge graph sys- tems and discuss the future research directions.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China(31871948)the Fundamental Research Funds,and the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences to H.Z.a grant from the Fundamental Research Funds for the Central Universities to S.L.
文摘Recently developed CRISPR-mediated base editors,which enable the generation of num erous nucleotide changes in target genomic regions,have been widely adopted for gene correction and generation of crop germ plasms containing im portant gain-of-function genetic variations.How ever,to engineer target genes with unknown functional SNPs remains challenging.To address this issue,we present here abase-e diting-mediated gene evolution(BEMGE)m ethod,employing both Cas9n-based cytosine and adenine base editors as well as a single-guide RNA(sgRNA)library tiling the full-length coding region,for developing novel rice germ plasm swith mutations in any endogenous gene.To this end,OsALS1 was artificially evolved in rice cells using BEMGE through both Agrobacterium-mediated and particle-bom bardment-mediated transform ation.Four different types of amino acid substitutions in the evolved OsALS1,derived from two sites that have never been targeted by natural or human selection during rice dom estication,were identified,conferring varying levels of tolerance to the herbicide bispyribac-sodium.Furtherm ore,the P171F substitution identified in a strong OsALS1 allele was quickly introduced into the commercial rice cultivar Nangeng 46 through precise base editing w ith the corresponding base editor and sgRNA.Collectively,these data indicate great potential of BEMGE in creating important genetic variants of target genes for crop improvement.
基金Supported by the National Nature Science Foundation of China (No. 30872009)the Earmarked Fund for Modern Agro-Industry Technology Research System of China (No. nycytx-23)
文摘Soil acidification is an important process in land degradation around the world as well as in China.Acidification of Alfisols was investigated in the tea gardens with various years of tea cultivation in the eastern China.Cultivation of tea plants caused soil acidification and soil acidity increased with the increase of tea cultivation period.Soil pH of composite samples from cultivated layers decreased by 1.37,1.62 and 1.85,respectively,after 13,34 and 54 years of tea plantation,as compared to the surface soil obtained from the unused land.Soil acidification rates at early stages of tea cultivation were found to be higher than those at the later stages.The acidification rate for the period of 0-13 years was as high as 4.40 kmol H + ha ?1 year ?1 for the cultivated layer samples.Soil acidification induced the decrease of soil exchangeable base cations and base cation saturation and thus increased the soil exchangeable acidity.Soil acidification also caused the decrease of soil cation exchange capacity,especially for the 54-year-old tea garden.Soil acidification induced by tea plantation also led to the increase of soil exchangeable Al and soluble Al,which was responsible for the Al toxicity to plants.
基金Supported by the National Key Technology R&D Program of China (No.2009BADC6B02)the National Natural Science Foundation of China (No.40971135)
文摘The liming potential of some crop residues and their biochars on an acid Ultisol was investigated using incubation experiments. Rice hulls showed greater liming potential than rice hull biochar, while soybean and pea straws had less liming potential than their biochars. Due to their higher alkalinity, biochars from legume materials increased soil pH much compared to biochars from non-legume materials. The alkalinity of biochars was a key factor affecting their liming potential, and the greater alkalinity of biochars led to greater reductions in soil acidity. The incorporation of biochars decreased soil exchangeable acidity and increased soil exchangeable base cations and base saturation, thus improving soil fertility.
文摘采用碱活化过一硫酸盐(peroxymonosulfate,PMS)对环丙沙星(ciprofloxacin,CIP)的去除进行了系统地研究.结果表明,碱活化PMS体系能够高效地去除CIP.通过自由基捕获实验确定了单线态氧(~1O_2)和超氧自由基(O_2^-·)是反应体系中的主要活性物种.NaOH浓度、PMS浓度、反应温度和共存阴离子等对CIP在碱活化PMS体系中的去除均有一定影响.随着NaOH和PMS浓度的增加,CIP的降解均呈现出先增加后降低的趋势.提高反应温度能够加大CIP的反应速率,经过阿伦尼乌斯方程拟合得到的反应活化能为5.09 k J·mol^(-1).不同的阴离子对CIP的去除呈现不同的影响:Cl^-、SO_4^(2-)和NO_3^-对CIP的降解没有呈现明显的作用,H_2PO_4^(2-)能够有效地抑制环丙沙星的去除,而CO_3^(2-)极大地促进了反应进程.通过UPLC-MS/MS可检测到10种降解产物,CIP分子结构中的哌嗪环易于受到活性物种的攻击.
文摘The article studies the theoretical basis for the hypothesis of brain intestine connection from 3 perspectives,suggesting the discovery of brain gut peptide make the hypothesis possible.And the neuro gastroenterology offers another foundation.The clinical report on the relationship of brain intestinal disease is the base of this hypothesis. This hypothesis is vital to traditional Chinese medicine and treatment of brain intestinal disease.
文摘The fuzzy control algorithms used commonly at present are all regarded as some interpolation functions, which is in essence equivalent to discrete response functions to be fitted. This means that fuzzy control method is similar to finite element method in mathematical physics, which is a kind of direct manner or numerical method in control systems.
文摘Information on the Internet is fragmented and presented in different data sources, which makes automatic knowledge harvesting and understanding formidable for ma- chines, and even for humans. Knowledge graphs have be- come prevalent in both of industry and academic circles these years, to be one of the most efficient and effective knowledge integration approaches. Techniques for knowledge graph construction can mine information from either structured, semi-structured, or even unstructured data sources, and fi- nally integrate the information into knowledge, represented in a graph. Furthermore, knowledge graph is able to organize information in an easy-to-maintain, easy-to-understand and easy-to-use manner. In this paper, we give a summarization of techniques for constructing knowledge graphs. We review the existing knowledge graph systems developed by both academia and industry. We discuss in detail about the process of building knowledge graphs, and survey state-of-the-art techniques for automatic knowledge graph checking and expansion via log- ical inferring and reasoning. We also review the issues of graph data management by introducing the knowledge data models and graph databases, especially from a NoSQL point of view. Finally, we overview current knowledge graph sys- tems and discuss the future research directions.
