Property path is the latest navigational extension of the standard query language SPARQL 1.1 for the Semantic Web.However,in the existing SPARQL query systems which support property path,the query efficiency is very l...Property path is the latest navigational extension of the standard query language SPARQL 1.1 for the Semantic Web.However,in the existing SPARQL query systems which support property path,the query efficiency is very low and does not support reasoning.This paper proposes a new existential semantics which has polynomial-time evaluation complexity and an equivalent relationship with the current semantics,and transforms the property path expressions to the extended nested regular expressions based on the existential semantics and proves the semantic equivalence after the transformation considering the RDFS semantics.The property path query engine is achieved by implementing the nested regular expressions algorithm and the transformation rules from the property path expressions to the nested regular expressions,which maintains the syntax simplicity of property path and the goal-oriented polynomial-time reasoning to avoid computing the RDF graph closure.The experiment results not only show the characteristics of query engine based on the existential semantics in efficiency and reasoning,but also further validate the equivalence between the results based on current semantics and those based on the existential semantics for property path after the removal of duplicate values.展开更多
Benzo[a]pyrene （B[a]P） is an increasingly present marine environmental pollutant, yet our understanding of the long-term consequences of reproductive toxicity in marine benthic polychaetes remains limited. To test t...Benzo[a]pyrene （B[a]P） is an increasingly present marine environmental pollutant, yet our understanding of the long-term consequences of reproductive toxicity in marine benthic polychaetes remains limited. To test the reproductive toxicity of B[a]P on polychaetes, Perinereis nuntia was exposed to B[a]P-contaminated artificial seawater and sexual maturation, the sex ratio, number of eggs spawned, fertilization and hatching rated, as well as vitellogenin （VTG） mRNA expression levels were analyzed. A low concentration of B[a]P （2.5 gg/L） had no effects on the rate of sexual maturation, spawning, or fertilization but significantly increased the sex ratio （female： male） from 1.6±0.15：1 to 2.3±0.18：1, inhibited hatching rate by 27%, and significantly increased VTG mRNA expression level by 3.7-fold following a 60-day exposure, compared with those in the solvent controls. A higher concentration of B[a]P （25 μg/L） caused more serious effects; sexual maturation, fertilization success, and hatching decreased by 31%, 17% and 46%, respectively, and the sex ratio （female： male） and VTG mRNA gene expression level increased by 54% and 7.1-fold, respectively. These results demonstrate that sublethal concentrations of B[a]P negatively affect reproductive performance of the sandworm P. nuntia.展开更多
Colorectal cancer(CRC) is a biologically heterogeneous disease with diverse clinical outcomes and responses to treatment. In the past two to three decades, a major effort has focused on classifying colorectal cancer s...Colorectal cancer(CRC) is a biologically heterogeneous disease with diverse clinical outcomes and responses to treatment. In the past two to three decades, a major effort has focused on classifying colorectal cancer subtypes based on causation, etiology, gene expression profiles, different pathways, and translational data from clinical trials. The goal is to uncover prognostic and predictive factors for outcomes in patients with colorectal cancer and to guide therapeutic approaches and management for the improvement of overall survival. Significant advances have been achieved in this area. However, tremendous work is still needed to accomplish the goal of better understanding intratumoral heterogeneity and the influence of the colonic environment, among other facets of colorectal cancer.展开更多
The purpose of this paper is to show the influence of the edge-effect on the electric field distribution, and hence on the inner capacitance and outer capacitance of a cylindrical capacitor surrounded by an insulating...The purpose of this paper is to show the influence of the edge-effect on the electric field distribution, and hence on the inner capacitance and outer capacitance of a cylindrical capacitor surrounded by an insulating medium. To generalize the results, a two-dimensional axisymmetric finite element model of a cylindrical capacitor has been generated and the problem has been resolved taking into account the distance between the conductors for a complete set of dimensions. The available obtained results have been compared with previous published works. Finally, using statistical tools, the mathematical expression for computing the relationship between capacitance and insulation gap and cylindrical plates dimensions has been obtained.展开更多
基金Supported by National Natural Science Foundation of China(No. 61070202 and No. 61100049)
文摘Property path is the latest navigational extension of the standard query language SPARQL 1.1 for the Semantic Web.However,in the existing SPARQL query systems which support property path,the query efficiency is very low and does not support reasoning.This paper proposes a new existential semantics which has polynomial-time evaluation complexity and an equivalent relationship with the current semantics,and transforms the property path expressions to the extended nested regular expressions based on the existential semantics and proves the semantic equivalence after the transformation considering the RDFS semantics.The property path query engine is achieved by implementing the nested regular expressions algorithm and the transformation rules from the property path expressions to the nested regular expressions,which maintains the syntax simplicity of property path and the goal-oriented polynomial-time reasoning to avoid computing the RDF graph closure.The experiment results not only show the characteristics of query engine based on the existential semantics in efficiency and reasoning,but also further validate the equivalence between the results based on current semantics and those based on the existential semantics for property path after the removal of duplicate values.
基金Supported by the Guangdong High-Level University Project"Green Technologies for Marine Industries"(No.130-33106703)Guangdong Natural Science Foundation(2016A030313065)the Outstanding Young Teachers of Guangdong Colleges and Universities(No.YQ2015074)
文摘Benzo[a]pyrene （B[a]P） is an increasingly present marine environmental pollutant, yet our understanding of the long-term consequences of reproductive toxicity in marine benthic polychaetes remains limited. To test the reproductive toxicity of B[a]P on polychaetes, Perinereis nuntia was exposed to B[a]P-contaminated artificial seawater and sexual maturation, the sex ratio, number of eggs spawned, fertilization and hatching rated, as well as vitellogenin （VTG） mRNA expression levels were analyzed. A low concentration of B[a]P （2.5 gg/L） had no effects on the rate of sexual maturation, spawning, or fertilization but significantly increased the sex ratio （female： male） from 1.6±0.15：1 to 2.3±0.18：1, inhibited hatching rate by 27%, and significantly increased VTG mRNA expression level by 3.7-fold following a 60-day exposure, compared with those in the solvent controls. A higher concentration of B[a]P （25 μg/L） caused more serious effects; sexual maturation, fertilization success, and hatching decreased by 31%, 17% and 46%, respectively, and the sex ratio （female： male） and VTG mRNA gene expression level increased by 54% and 7.1-fold, respectively. These results demonstrate that sublethal concentrations of B[a]P negatively affect reproductive performance of the sandworm P. nuntia.
文摘Colorectal cancer(CRC) is a biologically heterogeneous disease with diverse clinical outcomes and responses to treatment. In the past two to three decades, a major effort has focused on classifying colorectal cancer subtypes based on causation, etiology, gene expression profiles, different pathways, and translational data from clinical trials. The goal is to uncover prognostic and predictive factors for outcomes in patients with colorectal cancer and to guide therapeutic approaches and management for the improvement of overall survival. Significant advances have been achieved in this area. However, tremendous work is still needed to accomplish the goal of better understanding intratumoral heterogeneity and the influence of the colonic environment, among other facets of colorectal cancer.
文摘The purpose of this paper is to show the influence of the edge-effect on the electric field distribution, and hence on the inner capacitance and outer capacitance of a cylindrical capacitor surrounded by an insulating medium. To generalize the results, a two-dimensional axisymmetric finite element model of a cylindrical capacitor has been generated and the problem has been resolved taking into account the distance between the conductors for a complete set of dimensions. The available obtained results have been compared with previous published works. Finally, using statistical tools, the mathematical expression for computing the relationship between capacitance and insulation gap and cylindrical plates dimensions has been obtained.
