South of Hangzhou Bay, Zhejiang Province, exhibits an embayed muddy coastline, with the muddy beaches of embayments extending continuously seaward.The source of sediments on this coast presents an interesting problem ...South of Hangzhou Bay, Zhejiang Province, exhibits an embayed muddy coastline, with the muddy beaches of embayments extending continuously seaward.The source of sediments on this coast presents an interesting problem to marine geologists and geomorphologists .The total annual load of sediments from the rivers of Zhejiang is only 12×106t.These materials affect only the area near the river mouths. The paper showed that the sediment along the coast of Zhejiang mainly comes from the Changjiang Estuary through analysing the time and space variations of suspended sediment, the features of sediment and the sedimentary transport.The Changjiang River is the largest river system in China, its sediment to the sea amounting to 468×106t. The sediment during summer transports mainly eastward, and is affected by the water body with high temperature, salinity and transparency; the winter season is the period with high sediment concentration. The sediment of the Changjiang Estuary transports together with the longshore current of the East China Sea southward, the southern boundary can reach the sea region approximately 500 km from the Shacheng Harbour. The accretion rate seaward has been about 10 - 30 m since the 16th century. The sediment movement combined the longitudinal with the lateral, so that the muddy flats progress continuously seaward under the construction of the seashore profile .展开更多
[Objectives]This study was conducted to explore the genetic evolution of Escherichia fergusonii in different countries and regions,and to clarify the genetic relationship of E.fergusonii in different countries and reg...[Objectives]This study was conducted to explore the genetic evolution of Escherichia fergusonii in different countries and regions,and to clarify the genetic relationship of E.fergusonii in different countries and regions.[Methods]Bioinformatics method and bacterial 16 S rRNA sequencing technology were used to sort out and prune 16 S rRNA genes isolated in laboratory and searched in NCBI database to construct a molecular evolutionary tree for analysis and comparison.[Results]The direction of evolution of E.fergusonii has broken through regions,and there was cross evolution among continents.The origin of E.fergusonii was the Asian continent,and its adaptability to arid climate was not strong.[Conclusions]This study revealed the genetic evolution laws of E.fergusonii in the spread and mutation of livestock and poultry diseases,and provides a theoretical reference for the prevention and treatment of the disease.展开更多
The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelo...The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.展开更多
With the urban regionalization and regional urbanization, the spatial structure of cluster appears in some metropolitan areas, among which Wuhan can be taken as a typical case. This paper analyzes the formation of Wuh...With the urban regionalization and regional urbanization, the spatial structure of cluster appears in some metropolitan areas, among which Wuhan can be taken as a typical case. This paper analyzes the formation of Wuhan metropolitan cluster space from the perspective of power relationship. A "twin-city" approach is developed in the peripheral area of Wuhan caused by the game between local governments at different levels. With the equal development opportunities in all directions and the alliances between different district governments and capital, the balancedly embedded cluster space is formed in Wuhan metropolitan area. And if there are no huge internal and external changes, the cluster space in Wuhan will continue to develop.展开更多
The amended Land Administration Law of the People's Republic of China,which took effect on Jan.1,2020,once again permitted the market entry of rural collectively-owned commercial construction land(RCCCL).Prior to ...The amended Land Administration Law of the People's Republic of China,which took effect on Jan.1,2020,once again permitted the market entry of rural collectively-owned commercial construction land(RCCCL).Prior to this amendment,there was a debate among scholars regarding whether RCCCL should be reintroduced into the market.The core of the debate centered on the competing claims of stakeholders and the balance in the distribution of market benefits.This study employs stakeholder theory to construct an analytical framework,focusing on whether this re-entry might lead to an outcome similar to the 1998 market closure and whether market equilibrium could again be disrupted.By examining the case of Daxing District,Beijing,this paper compares the market entry of RCCCL across different historical contexts and analyzes stakeholder changes at various stages.From the perspective of the stakeholder relationships,this paper summarizes the institutional lessons from this reform,aiming to propose a more sustainable mechanism for market entry and to inform the future implementation and development of the RCCCL market.展开更多
Impact statement Arsenic is the most common toxic metalloid in the environment.Nearly all organisms have genes for arsenic detoxification.Arsenic detoxification genes are frequently organized in chromosomal or plasmid...Impact statement Arsenic is the most common toxic metalloid in the environment.Nearly all organisms have genes for arsenic detoxification.Arsenic detoxification genes are frequently organized in chromosomal or plasmid-encoded arsenic resistance(ars)operons,which are commonly regulated by members of the ArsR transcriptional repressors.To date,three As(Ⅲ)-responsive ArsRs with different As(III)binding sites have been identified.Here,we identify a new type of As(Ⅲ)-responsive ArsR repressor that has an atypical As(Ⅲ)binding site and controls transcription of the ars operon of Arsenicibacter rosenii SM-1.Our results provide new insights into the classification and evolution relationship of the ArsR transcriptional repressors.展开更多
文摘South of Hangzhou Bay, Zhejiang Province, exhibits an embayed muddy coastline, with the muddy beaches of embayments extending continuously seaward.The source of sediments on this coast presents an interesting problem to marine geologists and geomorphologists .The total annual load of sediments from the rivers of Zhejiang is only 12×106t.These materials affect only the area near the river mouths. The paper showed that the sediment along the coast of Zhejiang mainly comes from the Changjiang Estuary through analysing the time and space variations of suspended sediment, the features of sediment and the sedimentary transport.The Changjiang River is the largest river system in China, its sediment to the sea amounting to 468×106t. The sediment during summer transports mainly eastward, and is affected by the water body with high temperature, salinity and transparency; the winter season is the period with high sediment concentration. The sediment of the Changjiang Estuary transports together with the longshore current of the East China Sea southward, the southern boundary can reach the sea region approximately 500 km from the Shacheng Harbour. The accretion rate seaward has been about 10 - 30 m since the 16th century. The sediment movement combined the longitudinal with the lateral, so that the muddy flats progress continuously seaward under the construction of the seashore profile .
基金National Undergraduate Innovation and Enterpreneurship Training Program(201810061047)。
文摘[Objectives]This study was conducted to explore the genetic evolution of Escherichia fergusonii in different countries and regions,and to clarify the genetic relationship of E.fergusonii in different countries and regions.[Methods]Bioinformatics method and bacterial 16 S rRNA sequencing technology were used to sort out and prune 16 S rRNA genes isolated in laboratory and searched in NCBI database to construct a molecular evolutionary tree for analysis and comparison.[Results]The direction of evolution of E.fergusonii has broken through regions,and there was cross evolution among continents.The origin of E.fergusonii was the Asian continent,and its adaptability to arid climate was not strong.[Conclusions]This study revealed the genetic evolution laws of E.fergusonii in the spread and mutation of livestock and poultry diseases,and provides a theoretical reference for the prevention and treatment of the disease.
基金supported by the National Youth Talent Program (A279021801)Key-Area R&D Program of Guangdong province (2022B0202060001)+4 种基金Key R&D Program of Shaanxi Province (2023-YBNY-008)the Science and Technology Innovation Team of Shaanxi (2021TD-32)the Natural Science Foundation of Shaanxi Province (2021JM-089, 2022JM-112 and 2022JQ-162)the Key R&D Project from Yangling Seed Industry Innovation Center (K3031322016)the Fundamental Research Fund from Northwest A&F University (2452022111)。
文摘The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.
基金National Natural Science Foundation Project"Study on Mechanism of Clustered Development of Large City in Central China and Key Technique of Related Spatial Control"(50878091),"Study on New-type Urbanization Path and Spatial Organization of Counties in Central Areas"(51178200)
文摘With the urban regionalization and regional urbanization, the spatial structure of cluster appears in some metropolitan areas, among which Wuhan can be taken as a typical case. This paper analyzes the formation of Wuhan metropolitan cluster space from the perspective of power relationship. A "twin-city" approach is developed in the peripheral area of Wuhan caused by the game between local governments at different levels. With the equal development opportunities in all directions and the alliances between different district governments and capital, the balancedly embedded cluster space is formed in Wuhan metropolitan area. And if there are no huge internal and external changes, the cluster space in Wuhan will continue to develop.
文摘The amended Land Administration Law of the People's Republic of China,which took effect on Jan.1,2020,once again permitted the market entry of rural collectively-owned commercial construction land(RCCCL).Prior to this amendment,there was a debate among scholars regarding whether RCCCL should be reintroduced into the market.The core of the debate centered on the competing claims of stakeholders and the balance in the distribution of market benefits.This study employs stakeholder theory to construct an analytical framework,focusing on whether this re-entry might lead to an outcome similar to the 1998 market closure and whether market equilibrium could again be disrupted.By examining the case of Daxing District,Beijing,this paper compares the market entry of RCCCL across different historical contexts and analyzes stakeholder changes at various stages.From the perspective of the stakeholder relationships,this paper summarizes the institutional lessons from this reform,aiming to propose a more sustainable mechanism for market entry and to inform the future implementation and development of the RCCCL market.
基金supported by the Natural Science Foundation of China(Grant Nos.42077210 and 41930758 to Ke Huang and Fang-jie Zhao,respectively).
文摘Impact statement Arsenic is the most common toxic metalloid in the environment.Nearly all organisms have genes for arsenic detoxification.Arsenic detoxification genes are frequently organized in chromosomal or plasmid-encoded arsenic resistance(ars)operons,which are commonly regulated by members of the ArsR transcriptional repressors.To date,three As(Ⅲ)-responsive ArsRs with different As(III)binding sites have been identified.Here,we identify a new type of As(Ⅲ)-responsive ArsR repressor that has an atypical As(Ⅲ)binding site and controls transcription of the ars operon of Arsenicibacter rosenii SM-1.Our results provide new insights into the classification and evolution relationship of the ArsR transcriptional repressors.
