借助CiteSpace软件,以中国知网CSSCI(中文社会科学引文索引)数据库和Web of Science核心合集数据库为数据源,对国内外社会资本研究的基本情况、热点和发展态势进行可视化分析。研究发现:国内外社会资本研究近10年的总体发文量水平较高,...借助CiteSpace软件,以中国知网CSSCI(中文社会科学引文索引)数据库和Web of Science核心合集数据库为数据源,对国内外社会资本研究的基本情况、热点和发展态势进行可视化分析。研究发现:国内外社会资本研究近10年的总体发文量水平较高,研究主题与内容呈现多元学科特征,英文研究起步相对较早,中文文献发表量增速更快,虽然国内研究机构更多,但机构间合作密度却更稀疏,且研究地域化倾向较为明显;国内外研究逐渐趋向细化与深入,既涉及宏观层面政治政策,也涉及中观层面的企业或社区治理,而英文文献近来更趋向于个体行为、老年人、心理健康等微观层面;国内外研究均紧密结合各国国情,英文文献更贴近于技术进步和社会热点,延伸到社交媒体抑郁、满意度、密切关系和“脸书”等研究内容,而中文文献与时代发展和社会现状深度融合,研究前沿主要集中于乡村振兴、数字经济、科技创新等内容。未来在经济高质量发展、区域协调发展、社会保障与民生等方面深化研究的同时,还应利用新的研究工具和方法探讨企业创新发展、网络消费与行为等中微观问题。展开更多
Random amplification polymorphicDNA(RAPD)markers were used to assess the genetic variations and the evolutionary relationships among all 14 individuals of a critically endangered Euryodendron excelsum(Theaceae)populat...Random amplification polymorphicDNA(RAPD)markers were used to assess the genetic variations and the evolutionary relationships among all 14 individuals of a critically endangered Euryodendron excelsum(Theaceae)population distributed in Ba Jia Zhen,Yangchun,Guangdong,China.Twenty-three random primers detected 156 sites,out of which 95(60.26%)were polymorphic loci.The number of the observed alleles was 1.6090,and the number of the effective alleles was 1.3471.Nei’s gene diversity was 0.1993,and Shannon index was 0.1534.A relatively high level of genetic variation was identified in E.excelsum.An unweighted pair group method with arithmetic mean(UPGMA)tree established from Jaccard similarity coefficients suggested that 14 individuals were clustered into two subgroups and that the No.2 plant was genetically distant from the rest of the individuals.The UPGMA clustering was also supported by a principle components analysis of RAPD phenotypic data.The management and conservation strategy of E.excelsum was proposed based on our results.展开更多
This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Pro...This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Province,southern China.Sequence length varied from 868 bp to 876 bp,indicating length polymorphism.Base com-position in the sequences was high in A+T content between 64.17%and 64.95%,and no recombination event occurred(Rm=0).Thirty haplotypes were identified based on statis-tical parsimony algorithm by running the TCS program.Populations of D.pectinatum in Hainan were lacking ge-netic differentiation.Such a deduction was supported by the observed FST values(0.00),AMOVA(24.17%of molecular variance attributed to difference among populations,P>0.05),high values of Nm(ranging from 1.92 to 2.50)and the branching structure in neighbor-joining(NJ)tree con-structed from haplotypes.A‘star-like’pattern was exhibited in the TCS network of trnL-F haplotypes,and majority of the haplotypes coalesced near the tips in NJ tree.Gene ge-nealogies of cpDNA haplotypes proposed a recent popula-tion expansion of D.pectinatum in Hainan,which was fur-ther supported by the results from Tajima’s D test and mis-match distribution analysis.Our data,in conjunction with geological and palynological evidences,showed that in the Holocene,due to global warming,refugee populations of D.pectinatum in Hainan might experience a range expan-sion.展开更多
文摘借助CiteSpace软件,以中国知网CSSCI(中文社会科学引文索引)数据库和Web of Science核心合集数据库为数据源,对国内外社会资本研究的基本情况、热点和发展态势进行可视化分析。研究发现:国内外社会资本研究近10年的总体发文量水平较高,研究主题与内容呈现多元学科特征,英文研究起步相对较早,中文文献发表量增速更快,虽然国内研究机构更多,但机构间合作密度却更稀疏,且研究地域化倾向较为明显;国内外研究逐渐趋向细化与深入,既涉及宏观层面政治政策,也涉及中观层面的企业或社区治理,而英文文献近来更趋向于个体行为、老年人、心理健康等微观层面;国内外研究均紧密结合各国国情,英文文献更贴近于技术进步和社会热点,延伸到社交媒体抑郁、满意度、密切关系和“脸书”等研究内容,而中文文献与时代发展和社会现状深度融合,研究前沿主要集中于乡村振兴、数字经济、科技创新等内容。未来在经济高质量发展、区域协调发展、社会保障与民生等方面深化研究的同时,还应利用新的研究工具和方法探讨企业创新发展、网络消费与行为等中微观问题。
基金supported by National Natural Science Foundation of China (No.30271094)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry (No.[2003]406)the“100 Talent Project”,the Chinese Academy of Sciences (No.05052903).
文摘Random amplification polymorphicDNA(RAPD)markers were used to assess the genetic variations and the evolutionary relationships among all 14 individuals of a critically endangered Euryodendron excelsum(Theaceae)population distributed in Ba Jia Zhen,Yangchun,Guangdong,China.Twenty-three random primers detected 156 sites,out of which 95(60.26%)were polymorphic loci.The number of the observed alleles was 1.6090,and the number of the effective alleles was 1.3471.Nei’s gene diversity was 0.1993,and Shannon index was 0.1534.A relatively high level of genetic variation was identified in E.excelsum.An unweighted pair group method with arithmetic mean(UPGMA)tree established from Jaccard similarity coefficients suggested that 14 individuals were clustered into two subgroups and that the No.2 plant was genetically distant from the rest of the individuals.The UPGMA clustering was also supported by a principle components analysis of RAPD phenotypic data.The management and conservation strategy of E.excelsum was proposed based on our results.
基金supported by the National Natural Science Foundation of China (Nos.30170789 and 30270153)the Natural Science Foundation of Guangdong Province,China (No.011125).
文摘This study determined the sequences of chloro-plast DNA(cpDNA)trnL-F non-coding regions of indi-viduals of a tropical coniferous species,Dacrydium pectinatum,collected from 12 natural populations located in Hainan Province,southern China.Sequence length varied from 868 bp to 876 bp,indicating length polymorphism.Base com-position in the sequences was high in A+T content between 64.17%and 64.95%,and no recombination event occurred(Rm=0).Thirty haplotypes were identified based on statis-tical parsimony algorithm by running the TCS program.Populations of D.pectinatum in Hainan were lacking ge-netic differentiation.Such a deduction was supported by the observed FST values(0.00),AMOVA(24.17%of molecular variance attributed to difference among populations,P>0.05),high values of Nm(ranging from 1.92 to 2.50)and the branching structure in neighbor-joining(NJ)tree con-structed from haplotypes.A‘star-like’pattern was exhibited in the TCS network of trnL-F haplotypes,and majority of the haplotypes coalesced near the tips in NJ tree.Gene ge-nealogies of cpDNA haplotypes proposed a recent popula-tion expansion of D.pectinatum in Hainan,which was fur-ther supported by the results from Tajima’s D test and mis-match distribution analysis.Our data,in conjunction with geological and palynological evidences,showed that in the Holocene,due to global warming,refugee populations of D.pectinatum in Hainan might experience a range expan-sion.
