This study was conducted to compare leaf anatomical structures and ap- parent plant print characteristics of 3 Vicia plants from Changbai Mountains applying structural botany principle and fingerprint identification t...This study was conducted to compare leaf anatomical structures and ap- parent plant print characteristics of 3 Vicia plants from Changbai Mountains applying structural botany principle and fingerprint identification technology, aiming at dis- cussing the structure evolution law of Vicia plants and providing scientific reference for research about classification, genetic relationship and evolutionary trend of this genus. The comparison of leaf anatomical structures of Vicia lilacina, V. pseu- dorobus and V. unijuga showed that： V. unijuga has tidily arranged leaf epidermal cells, thickened outer tangential wall cuticle, large diameter of xylem vessels, and developed midrib fibrocytes which form vascular bundle sheaths. Plant print identifi- cation results showed that the tested 3 plants showed remarkable differences in leaf apparent texture and anticlinal wall type though plant print characteristics of appar- ent structures of plants in the same genus had homologous similarity. V. lilacina has no subsidiary cells, and apparent textures of V. pseudorobus and V. unijuga are both of paracytic unequal type. Statistical analysis showed that V. unijuga is more advanced than V. pseudorobus. The 3 tested plants are in evolutionary rela- tionship of V. lilacina〈V, pseudorobus〈V, unijuga.展开更多
Most semi-structured data are of certain structure regularity. Having beenstored as structured data in relational database (RDB), they can be effectively managed by databasemanagement system (DBMS). Some semi-structur...Most semi-structured data are of certain structure regularity. Having beenstored as structured data in relational database (RDB), they can be effectively managed by databasemanagement system (DBMS). Some semi-structured data are difficult to transform due to theirirregular structures. We design an efficient algorithm and data structure for ensuring losslesstransformation. We bring forward an approach of schema extraction through data mining, in whichdifferent kinds of elements are transformed respectively and lossless mapping from semi-structureddata to structured data can be achieved.展开更多
In order to improve the quality of web search,a new query expansion method by choosing meaningful structure data from a domain database is proposed.It categories attributes into three different classes,named as concep...In order to improve the quality of web search,a new query expansion method by choosing meaningful structure data from a domain database is proposed.It categories attributes into three different classes,named as concept attribute,context attribute and meaningless attribute,according to their semantic features which are document frequency features and distinguishing capability features.It also defines the semantic relevance between two attributes when they have correlations in the database.Then it proposes trie-bitmap structure and pair pointer tables to implement efficient algorithms for discovering attribute semantic feature and detecting their semantic relevances.By using semantic attributes and their semantic relevances,expansion words can be generated and embedded into a vector space model with interpolation parameters.The experiments use an IMDB movie database and real texts collections to evaluate the proposed method by comparing its performance with a classical vector space model.The results show that the proposed method can improve text search efficiently and also improve both semantic features and semantic relevances with good separation capabilities.展开更多
Enterprise capital structure means the various resources, combination and relationships of enterprise raising capital as well as means the short or long debts, shareholders＇ rights and interest, and the proportional ...Enterprise capital structure means the various resources, combination and relationships of enterprise raising capital as well as means the short or long debts, shareholders＇ rights and interest, and the proportional relationships among constituting items. Capitals raised by enterprise from different ways constitute the capital sum. Because of changing enterprise operation, the capital structure is also various and it cannot be in a fixed proportion. Therefore, we need to optimize the capital structure of state-owned enterprises so as to reach the rational resources allocation and make the national economy develop soundly and rapidly. How to optimize it？ This is a big problem that we have to face. Debt-to-equity swap at the moment is only the transition for correcting capital structure of state-owned enterprises. Decreasing stocks owned by state is the inevitable choice for optimizing enterprise stock right.展开更多
Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential dep...Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential deposition of hydrogen,or mild hydrogen evolution/OH adsorption)and have served as model electrodes for unraveling the structure-performance relation in electrocatalysis.With the advancement of in situ electrochemical microscopy/spectroscopy techniques,subtle surface restructuring under mild electrochemical conditions has been achieved in the last decade.Surface restructuring can considerably modify electrocatalytic properties by generating/destroying highly active sites,thereby interfering with the deduction of the structure-performance relation.In this review,we summarize recent progress in the restructuring of well-defined Pt(-based)electrode surfaces under mild electrochemical conditions.The importance of the meticulous structural characterization of Pt electrodes before,during,and after electrochemical measurements is demonstrated using CO adsorption/oxidation,hydrogen adsorption/evolution,and oxygen reduction as examples.The implications of present findings for correctly identifying the reaction mechanisms and kinetics of other electrocatalytic systems are also briefly discussed.展开更多
The nature and origin of a fundamental quantum QSPR （QQSPR） equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions （DF）, a molecular set can be r...The nature and origin of a fundamental quantum QSPR （QQSPR） equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions （DF）, a molecular set can be reconstructed as a quantum multimolecular polyhedron （QMP）, whose vertices are formed by each molecular DF. According to QQSPR theory, complicated kinds of molecular properties, like biological activity or toxicity, of molecular sets can be calculated via the quantum expectation value of an approximate Hermitian operator, which can be evaluated with the geometrical information contained in the attached QMP via quantum similarity matrices. Practical ways of solving the QQSPR problem from the point of view of QMP geometrical structure are provided. Such a development results into a powerful algorithm, which can be implemented within molecular design as an alternative to the current classical QSPR procedures.展开更多
Trade facilitation is one of the five main agendas of the Belt and Road Initiative(BRI). Social network analysis has helped understand the complexity of trade networks, but existing studies tend to overlook the fact t...Trade facilitation is one of the five main agendas of the Belt and Road Initiative(BRI). Social network analysis has helped understand the complexity of trade networks, but existing studies tend to overlook the fact that not all bilateral trade relations are equally important to a country. To fill this gap in the literature, this paper focuses on the top 2 trade relations networks to illuminate the structure and evolution of B&R trade relations, the relative positions of different countries, and changes in the composition of trade communities(e.g., the community leaders) and the changing patterns of trade between them. We find rich dynamics over time both inter-and intra-communities. The overall international trade networks of B&R countries experienced a leadership change from Russia to China on one hand, some temporary communities experienced emergence, disappearance(e.g. the Kuwait-and Thailand-led communities) or reemergence(e.g. Poland-led community), and a community membership was generally consistent on the other hand. Since the future impacts of China's BRI will depend on the degree of integration of the connected regions, some countries with stable and high centrality indices(e.g. Russia, Singapore, Serbia, Greece, Turkey, Iran, Poland, Hungary and Romania) could be selected by China as strategic regional partners, and countries with a strategically important geographical position but weak trade links(e.g. Myanmar, Pakistan, and Belarus) should be prioritized.展开更多
Estrogen compounds may pose a serious threat to the health of humans and wildlife. The estrogen receptor （ER） exists as two subtypes, ERα and ERβ. Compounds might have different relative affinities and binding mod...Estrogen compounds may pose a serious threat to the health of humans and wildlife. The estrogen receptor （ER） exists as two subtypes, ERα and ERβ. Compounds might have different relative affinities and binding modes for ERα and ERβ. In this study, the heuristic method was performed on 31 compounds binding to ERβ to select 5 variances most related to the activity （LogRBA） from 1524 variances, which were then employed to develop the best model with the significant correlation and the best predictive power （γ^2 = 0.829, q^2LOO = 0.742, γ^2pred = 0.772, q^2ext = 0.724, RMSEE = 0.395） using multiple linear regression （MLR）. The model derived identified critical structural features related to the activity of binding to ERβ. The applicability domain （AD） of the model was assessed by Williams plot.展开更多
The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as ...The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2 b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2 b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure–activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2 b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2 b receptor, which shed lights on the development of novel drugs as CCR2 b receptor antagonists for preventing inflammation related diseases.展开更多
基金Supported by Natural Science Foundation of China(41271231)~~
文摘This study was conducted to compare leaf anatomical structures and ap- parent plant print characteristics of 3 Vicia plants from Changbai Mountains applying structural botany principle and fingerprint identification technology, aiming at dis- cussing the structure evolution law of Vicia plants and providing scientific reference for research about classification, genetic relationship and evolutionary trend of this genus. The comparison of leaf anatomical structures of Vicia lilacina, V. pseu- dorobus and V. unijuga showed that： V. unijuga has tidily arranged leaf epidermal cells, thickened outer tangential wall cuticle, large diameter of xylem vessels, and developed midrib fibrocytes which form vascular bundle sheaths. Plant print identifi- cation results showed that the tested 3 plants showed remarkable differences in leaf apparent texture and anticlinal wall type though plant print characteristics of appar- ent structures of plants in the same genus had homologous similarity. V. lilacina has no subsidiary cells, and apparent textures of V. pseudorobus and V. unijuga are both of paracytic unequal type. Statistical analysis showed that V. unijuga is more advanced than V. pseudorobus. The 3 tested plants are in evolutionary rela- tionship of V. lilacina〈V, pseudorobus〈V, unijuga.
文摘Most semi-structured data are of certain structure regularity. Having beenstored as structured data in relational database (RDB), they can be effectively managed by databasemanagement system (DBMS). Some semi-structured data are difficult to transform due to theirirregular structures. We design an efficient algorithm and data structure for ensuring losslesstransformation. We bring forward an approach of schema extraction through data mining, in whichdifferent kinds of elements are transformed respectively and lossless mapping from semi-structureddata to structured data can be achieved.
基金Program for New Century Excellent Talents in University(No.NCET-06-0290)the National Natural Science Foundation of China(No.60503036)the Fok Ying Tong Education Foundation Award(No.104027)
文摘In order to improve the quality of web search,a new query expansion method by choosing meaningful structure data from a domain database is proposed.It categories attributes into three different classes,named as concept attribute,context attribute and meaningless attribute,according to their semantic features which are document frequency features and distinguishing capability features.It also defines the semantic relevance between two attributes when they have correlations in the database.Then it proposes trie-bitmap structure and pair pointer tables to implement efficient algorithms for discovering attribute semantic feature and detecting their semantic relevances.By using semantic attributes and their semantic relevances,expansion words can be generated and embedded into a vector space model with interpolation parameters.The experiments use an IMDB movie database and real texts collections to evaluate the proposed method by comparing its performance with a classical vector space model.The results show that the proposed method can improve text search efficiently and also improve both semantic features and semantic relevances with good separation capabilities.
文摘Enterprise capital structure means the various resources, combination and relationships of enterprise raising capital as well as means the short or long debts, shareholders＇ rights and interest, and the proportional relationships among constituting items. Capitals raised by enterprise from different ways constitute the capital sum. Because of changing enterprise operation, the capital structure is also various and it cannot be in a fixed proportion. Therefore, we need to optimize the capital structure of state-owned enterprises so as to reach the rational resources allocation and make the national economy develop soundly and rapidly. How to optimize it？ This is a big problem that we have to face. Debt-to-equity swap at the moment is only the transition for correcting capital structure of state-owned enterprises. Decreasing stocks owned by state is the inevitable choice for optimizing enterprise stock right.
文摘Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential deposition of hydrogen,or mild hydrogen evolution/OH adsorption)and have served as model electrodes for unraveling the structure-performance relation in electrocatalysis.With the advancement of in situ electrochemical microscopy/spectroscopy techniques,subtle surface restructuring under mild electrochemical conditions has been achieved in the last decade.Surface restructuring can considerably modify electrocatalytic properties by generating/destroying highly active sites,thereby interfering with the deduction of the structure-performance relation.In this review,we summarize recent progress in the restructuring of well-defined Pt(-based)electrode surfaces under mild electrochemical conditions.The importance of the meticulous structural characterization of Pt electrodes before,during,and after electrochemical measurements is demonstrated using CO adsorption/oxidation,hydrogen adsorption/evolution,and oxygen reduction as examples.The implications of present findings for correctly identifying the reaction mechanisms and kinetics of other electrocatalytic systems are also briefly discussed.
文摘The nature and origin of a fundamental quantum QSPR （QQSPR） equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions （DF）, a molecular set can be reconstructed as a quantum multimolecular polyhedron （QMP）, whose vertices are formed by each molecular DF. According to QQSPR theory, complicated kinds of molecular properties, like biological activity or toxicity, of molecular sets can be calculated via the quantum expectation value of an approximate Hermitian operator, which can be evaluated with the geometrical information contained in the attached QMP via quantum similarity matrices. Practical ways of solving the QQSPR problem from the point of view of QMP geometrical structure are provided. Such a development results into a powerful algorithm, which can be implemented within molecular design as an alternative to the current classical QSPR procedures.
基金National Social Science Foundation of China,No.17VDL008The Project of Bureau of International Cooperation of the Chinese Academy of Sciences,No.131A11KYSB20170014+1 种基金National Natural Science Foundation of China,No.41530751,No.41471113,No.41701125Ministry of Education of the Republic of Korea and the National Research Foundation of Korea,No.NRF-2015S1A3A2047036
文摘Trade facilitation is one of the five main agendas of the Belt and Road Initiative(BRI). Social network analysis has helped understand the complexity of trade networks, but existing studies tend to overlook the fact that not all bilateral trade relations are equally important to a country. To fill this gap in the literature, this paper focuses on the top 2 trade relations networks to illuminate the structure and evolution of B&R trade relations, the relative positions of different countries, and changes in the composition of trade communities(e.g., the community leaders) and the changing patterns of trade between them. We find rich dynamics over time both inter-and intra-communities. The overall international trade networks of B&R countries experienced a leadership change from Russia to China on one hand, some temporary communities experienced emergence, disappearance(e.g. the Kuwait-and Thailand-led communities) or reemergence(e.g. Poland-led community), and a community membership was generally consistent on the other hand. Since the future impacts of China's BRI will depend on the degree of integration of the connected regions, some countries with stable and high centrality indices(e.g. Russia, Singapore, Serbia, Greece, Turkey, Iran, Poland, Hungary and Romania) could be selected by China as strategic regional partners, and countries with a strategically important geographical position but weak trade links(e.g. Myanmar, Pakistan, and Belarus) should be prioritized.
基金supported by the Science and Technology Development Foundation Key Project of Nanjing Medical University (09NJMUZ16)
文摘Estrogen compounds may pose a serious threat to the health of humans and wildlife. The estrogen receptor （ER） exists as two subtypes, ERα and ERβ. Compounds might have different relative affinities and binding modes for ERα and ERβ. In this study, the heuristic method was performed on 31 compounds binding to ERβ to select 5 variances most related to the activity （LogRBA） from 1524 variances, which were then employed to develop the best model with the significant correlation and the best predictive power （γ^2 = 0.829, q^2LOO = 0.742, γ^2pred = 0.772, q^2ext = 0.724, RMSEE = 0.395） using multiple linear regression （MLR）. The model derived identified critical structural features related to the activity of binding to ERβ. The applicability domain （AD） of the model was assessed by Williams plot.
基金supported by the Major Scientific and Technological Special Project for Significant New Drugs Creation(No.2012ZX09504001-001)National Natural Science Foundation of China(No.81102876+2 种基金81430082)the Fundamental Research Funds for the Central Universities(No.2015ZD005)333 high level project of Jiangsu Province(NO.BRA2014245)
文摘The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2 b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2 b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure–activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2 b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2 b receptor, which shed lights on the development of novel drugs as CCR2 b receptor antagonists for preventing inflammation related diseases.
