针对障碍空间中不确定对象的组k最近邻查询问题,提出了Pk OGNN(probabilistic k obstructed group nearest neighbor query)查询方法。Pk OGNN查询方法主要包括4个子算法:Compadist_o(),SpatialPru(),PruInterEnt()和PkOGNN(),这些子算...针对障碍空间中不确定对象的组k最近邻查询问题,提出了Pk OGNN(probabilistic k obstructed group nearest neighbor query)查询方法。Pk OGNN查询方法主要包括4个子算法:Compadist_o(),SpatialPru(),PruInterEnt()和PkOGNN(),这些子算法分别是集总障碍距离的计算方法、空间修剪方法、根据空间修剪方法进行R树中间结点修剪、最终精炼查询方法。所提Pk OGNN查询方法通过集成有效的修剪策略以便减少Pk OGNN的搜索空间,得到正确的k GNNs。理论研究和实验结果表明,所提方法具有较好的性能。展开更多
Spermatogonia! stem cells（SSCs） form the foundation for spermatogenesis and sustain male fertility.To explore the regulatory mechanisms of chicken SSCs generation,we obtained highly purified chicken embryonic stem c...Spermatogonia! stem cells（SSCs） form the foundation for spermatogenesis and sustain male fertility.To explore the regulatory mechanisms of chicken SSCs generation,we obtained highly purified chicken embryonic stem cells（ESCs）,primordial germ cells（PGCs） and SSCs by fluorescence-activated cell sorting（FACS）.High-throughput analysis methods（RNA-Seq） were used to sequence the transcriptome level of these cells.Gene ontology and Kyoto encyclopedia of genes and genomes（KEGG） pathway enrichment were used to analyze RNA-Seq results.BMP4 was used to induce chicken ESCs differentiation to SSCs-like cells in vitro.The quantitative real-time（qRT）-PCR was used to detect the expression changes of the key genes.The results showed that 22 relevant critical pathways were found by RNA-Seq,one of them was the Janus kinase/signal transducer and activator of transcription（JAK/STAT） signaling pathway.Total of 103 related genes were detected in this pathway.Protein-protein interactions analysis found that 87 proteins were significantly related to 19 key proteins in this pathway.These 87 proteins were enriched in 21 biological processes and 18 signaling pathways.Moreover,during the differentiation of chicken ESCs to SSCs-like cells induced by BMP4 in vitro,JAK2 and STAT3 were activated.The qRT-PCR results showed that the expression trends of JAK2 and STAT3 were basically the same as in vivo.We concluded that JAK/STAT signaling pathway plays an important role in the process of chicken SSCs generation both in vivo and in vitro;it may achieve its function through multiple biological processes and other related pathways.展开更多
基金supported by the National Natural Science Foundation of China(31272429,31472087)the Specialized Research Fund for the Doctoral Program of Higher Education,China(20123250120009)+2 种基金the China Postdoctoral Science Foundation Funded Project(2012M511326,2014T70550)the Research and Innovation Program for Graduate Cultivation of Jiangsu Province,China(CXZZ13_0909)the project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Spermatogonia! stem cells（SSCs） form the foundation for spermatogenesis and sustain male fertility.To explore the regulatory mechanisms of chicken SSCs generation,we obtained highly purified chicken embryonic stem cells（ESCs）,primordial germ cells（PGCs） and SSCs by fluorescence-activated cell sorting（FACS）.High-throughput analysis methods（RNA-Seq） were used to sequence the transcriptome level of these cells.Gene ontology and Kyoto encyclopedia of genes and genomes（KEGG） pathway enrichment were used to analyze RNA-Seq results.BMP4 was used to induce chicken ESCs differentiation to SSCs-like cells in vitro.The quantitative real-time（qRT）-PCR was used to detect the expression changes of the key genes.The results showed that 22 relevant critical pathways were found by RNA-Seq,one of them was the Janus kinase/signal transducer and activator of transcription（JAK/STAT） signaling pathway.Total of 103 related genes were detected in this pathway.Protein-protein interactions analysis found that 87 proteins were significantly related to 19 key proteins in this pathway.These 87 proteins were enriched in 21 biological processes and 18 signaling pathways.Moreover,during the differentiation of chicken ESCs to SSCs-like cells induced by BMP4 in vitro,JAK2 and STAT3 were activated.The qRT-PCR results showed that the expression trends of JAK2 and STAT3 were basically the same as in vivo.We concluded that JAK/STAT signaling pathway plays an important role in the process of chicken SSCs generation both in vivo and in vitro;it may achieve its function through multiple biological processes and other related pathways.
