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 | Acesso ao texto completo restrito à biblioteca da Embrapa Agricultura Digital. Para informações adicionais entre em contato com cnptia.biblioteca@embrapa.br. |
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Registro Completo |
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Biblioteca(s): |
Embrapa Agricultura Digital. |
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Data corrente: |
12/03/2010 |
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Data da última atualização: |
30/01/2020 |
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Tipo da produção científica: |
Artigo em Anais de Congresso / Nota Técnica |
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Autoria: |
MARCACINI, R. M.; MOURA, M. F.; REZENDE, S. O. |
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Afiliação: |
RICARDO MARCONDES MARCACINI, ICMC/USP; MARIA FERNANDA MOURA, CNPTIA; SOLANGE OLIVEIRA REZENDE, ICMC/USP. |
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Título: |
Uma abordagem para seleção de grupos significativos em agrupamento hierárquico de documentos. |
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Ano de publicação: |
2009 |
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Fonte/Imprenta: |
In: CONGRESSO DA SOCIEDADE BRASILEIRA DE COMPUTAÇÃO, 29., 2009, Bento Gonçalves. Anais... Rio Grande do SUL: Instituto de Informática UFRGS, 2009. |
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Páginas: |
p. 929-938. |
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ISSN: |
2175-2761 |
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Idioma: |
Português |
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Notas: |
CSBC 2009. |
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Conteúdo: |
O agrupamento hierárquico de documentos geralmente fornece muitos grupos e subgrupos, di?cultando a análise e interpretação dos resultados. Neste trabalho é apresentado uma abordagem para obtenção de hierarquias de documentos reduzidas, a partir das hierarquias originais, selecionando-se apenas os grupos mais signi?cantes. A seleção é apoiada por medidas de qualidade de grupos, adaptadas para a alta dimensionalidade de dados textuais e para considerar o relacionamento hierárquico entre os grupos. Uma avaliacao experimental foi realizada em 10 coleções de documentos e três diferentes algoritmos de agrupamento hierárquico; apresentando bons resultados. |
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Palavras-Chave: |
Agrupamento hierárquico de documentos; Compactação da hierarquia; Hierarchical document clustering; Hierarquia reduzida; Joinability; Qualidade de grupos; Quality measures of cluster; Seleção de grupos significativos. |
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Categoria do assunto: |
X Pesquisa, Tecnologia e Engenharia |
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Marc: |
LEADER 01631nam a2200265 a 4500
001 1661031
005 2020-01-30
008 2009 bl uuuu u00u1 u #d
022 $a2175-2761
100 1 $aMARCACINI, R. M.
245 $aUma abordagem para seleção de grupos significativos em agrupamento hierárquico de documentos.$h[electronic resource]
260 $aIn: CONGRESSO DA SOCIEDADE BRASILEIRA DE COMPUTAÇÃO, 29., 2009, Bento Gonçalves. Anais... Rio Grande do SUL: Instituto de Informática UFRGS$c2009
300 $ap. 929-938.
500 $aCSBC 2009.
520 $aO agrupamento hierárquico de documentos geralmente fornece muitos grupos e subgrupos, di?cultando a análise e interpretação dos resultados. Neste trabalho é apresentado uma abordagem para obtenção de hierarquias de documentos reduzidas, a partir das hierarquias originais, selecionando-se apenas os grupos mais signi?cantes. A seleção é apoiada por medidas de qualidade de grupos, adaptadas para a alta dimensionalidade de dados textuais e para considerar o relacionamento hierárquico entre os grupos. Uma avaliacao experimental foi realizada em 10 coleções de documentos e três diferentes algoritmos de agrupamento hierárquico; apresentando bons resultados.
653 $aAgrupamento hierárquico de documentos
653 $aCompactação da hierarquia
653 $aHierarchical document clustering
653 $aHierarquia reduzida
653 $aJoinability
653 $aQualidade de grupos
653 $aQuality measures of cluster
653 $aSeleção de grupos significativos
700 1 $aMOURA, M. F.
700 1 $aREZENDE, S. O.
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Registro original: |
Embrapa Agricultura Digital (CNPTIA) |
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Registro Completo
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
04/12/2018 |
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Data da última atualização: |
04/12/2018 |
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Tipo da produção científica: |
Artigo em Periódico Indexado |
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Circulação/Nível: |
A - 1 |
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Autoria: |
BRITTO, F. B.; SCHMIDT, A. J.; CARVALHO, A. M. F.; VASCONCELOS, C. C. M. P.; FARIAS, A. M.; BENTZEN, P.; DINIZ, F. M. |
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Afiliação: |
Universidade Federal do Piauí (UFPI) - Teresina, PI, Brazil.; Universidade Federal do Sul da Bahia (UFSB) - Teixeira de Freitas, BA, Brazil.; Pós-graduação - Embrapa Meio-Norte - Teresina - PI, Brazil.; Universidade Federal do Piauí (UFPI) - Northeast Biotechnology Network RENORBIO - Teresina, PI, Brazil.; Universidade Federal do Piauí (UFPI) - Northeast Biotechnology Network RENORBIO - Teresina, PI, Brazil.; Department of Biology, Dalhousie University - Halifax, NS, Canada.; FABIO MENDONCA DINIZ, CNPC. |
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Título: |
Population connectivity and larval dispersal of the exploited mangrove crab Ucides cordatus along the Brazilian coast. |
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Ano de publicação: |
2018 |
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Fonte/Imprenta: |
PeerJ, v. 6, Article e4702, Apr. 2018. |
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DOI: |
DOI 10.7717/peerj.4702 |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: Background: The mangrove crab Ucides cordatus is considered a key species for the ecological balance of mangrove forests and a major source of employment and income for traditional crab collectors in Brazil. Several studies evidenced weak genetic variation among populations due to an efficient larval transport. However, gene flow patterns of the species is poorly understood, with no information about migration rates. The influence of the two main Brazilian currents in larval dispersion is also not clear. In order to provide baseline information for conservation, planning and management of this important fishery resource, the present study aimed to estimate and evaluate spatial distribution of genetic diversity, migration rates and gene flow directivity among populations of U. cordatus in Brazil. Methods:Nine microsatellites were used to resolve population structure of 319 crabs collected from six sites located along the Brazilian coast. The degree of geographical differentiation included estimates of genetic diversity, population structure and gene flow models, with spatial analysis of shared alleles (SAShA), isolation by distance tests, AMOVA, discriminant analysis of principal components (DAPC) and Bayesian clustering. We estimated the amount of ongoing gene flow between clusters using the coalescent-based method implemented in Migrate-N. Results:Loci were highly polymorphic (average of 12.4 alleles per locus) evidencing high genetic variability. There was significant differentiation among localities, despite of the low value of FST (= 0.019; P < 0.001). FST and Jost's D indexes were also estimated in pairwise comparisons and showed significant differences between most of the surveyed site pairs (P < 0.05). Structure evidenced a single genetic group among samples, however SAShA pointed to a non-panmictic condition (P = 0.011). AMOVA detected four statistical significant clusters with low level of differentiation (FCT = 0.037; P = 0.023). The gene flow model that best described the population connectivity was the island model, with ?24 crabs being exchanged among localities per generation.DIscussion:The high migration rates found among localities seem to be the main force acting to sustain the distribution of the genetic diversity of U. cordatus. Despite the high gene flow and the weak population structure among samples, the significant genetic differences found suggest that gene flow alone does not bypass the effects of genetic drift, natural selection and/or human exploitation. These findings are vital for the establishment of a database to be used in the development of conservation programs. MenosAbstract: Background: The mangrove crab Ucides cordatus is considered a key species for the ecological balance of mangrove forests and a major source of employment and income for traditional crab collectors in Brazil. Several studies evidenced weak genetic variation among populations due to an efficient larval transport. However, gene flow patterns of the species is poorly understood, with no information about migration rates. The influence of the two main Brazilian currents in larval dispersion is also not clear. In order to provide baseline information for conservation, planning and management of this important fishery resource, the present study aimed to estimate and evaluate spatial distribution of genetic diversity, migration rates and gene flow directivity among populations of U. cordatus in Brazil. Methods:Nine microsatellites were used to resolve population structure of 319 crabs collected from six sites located along the Brazilian coast. The degree of geographical differentiation included estimates of genetic diversity, population structure and gene flow models, with spatial analysis of shared alleles (SAShA), isolation by distance tests, AMOVA, discriminant analysis of principal components (DAPC) and Bayesian clustering. We estimated the amount of ongoing gene flow between clusters using the coalescent-based method implemented in Migrate-N. Results:Loci were highly polymorphic (average of 12.4 alleles per locus) evidencing high genetic variability. There was signif... Mostrar Tudo |
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Palavras-Chave: |
Conservation; Fish Science; Marine Biology; Microsatellite; Microsatellites; Migration rate. |
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Thesagro: |
Ucides Cordatus. |
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Thesaurus NAL: |
Animal ecology; Animal genetics; Fisheries; Gene flow; Population structure. |
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Categoria do assunto: |
G Melhoramento Genético |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/187663/1/CNPC-2018-Population.pdf
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Marc: |
LEADER 03664naa a2200349 a 4500
001 2100647
005 2018-12-04
008 2018 bl uuuu u00u1 u #d
024 7 $aDOI 10.7717/peerj.4702$2DOI
100 1 $aBRITTO, F. B.
245 $aPopulation connectivity and larval dispersal of the exploited mangrove crab Ucides cordatus along the Brazilian coast.$h[electronic resource]
260 $c2018
520 $aAbstract: Background: The mangrove crab Ucides cordatus is considered a key species for the ecological balance of mangrove forests and a major source of employment and income for traditional crab collectors in Brazil. Several studies evidenced weak genetic variation among populations due to an efficient larval transport. However, gene flow patterns of the species is poorly understood, with no information about migration rates. The influence of the two main Brazilian currents in larval dispersion is also not clear. In order to provide baseline information for conservation, planning and management of this important fishery resource, the present study aimed to estimate and evaluate spatial distribution of genetic diversity, migration rates and gene flow directivity among populations of U. cordatus in Brazil. Methods:Nine microsatellites were used to resolve population structure of 319 crabs collected from six sites located along the Brazilian coast. The degree of geographical differentiation included estimates of genetic diversity, population structure and gene flow models, with spatial analysis of shared alleles (SAShA), isolation by distance tests, AMOVA, discriminant analysis of principal components (DAPC) and Bayesian clustering. We estimated the amount of ongoing gene flow between clusters using the coalescent-based method implemented in Migrate-N. Results:Loci were highly polymorphic (average of 12.4 alleles per locus) evidencing high genetic variability. There was significant differentiation among localities, despite of the low value of FST (= 0.019; P < 0.001). FST and Jost's D indexes were also estimated in pairwise comparisons and showed significant differences between most of the surveyed site pairs (P < 0.05). Structure evidenced a single genetic group among samples, however SAShA pointed to a non-panmictic condition (P = 0.011). AMOVA detected four statistical significant clusters with low level of differentiation (FCT = 0.037; P = 0.023). The gene flow model that best described the population connectivity was the island model, with ?24 crabs being exchanged among localities per generation.DIscussion:The high migration rates found among localities seem to be the main force acting to sustain the distribution of the genetic diversity of U. cordatus. Despite the high gene flow and the weak population structure among samples, the significant genetic differences found suggest that gene flow alone does not bypass the effects of genetic drift, natural selection and/or human exploitation. These findings are vital for the establishment of a database to be used in the development of conservation programs.
650 $aAnimal ecology
650 $aAnimal genetics
650 $aFisheries
650 $aGene flow
650 $aPopulation structure
650 $aUcides Cordatus
653 $aConservation
653 $aFish Science
653 $aMarine Biology
653 $aMicrosatellite
653 $aMicrosatellites
653 $aMigration rate
700 1 $aSCHMIDT, A. J.
700 1 $aCARVALHO, A. M. F.
700 1 $aVASCONCELOS, C. C. M. P.
700 1 $aFARIAS, A. M.
700 1 $aBENTZEN, P.
700 1 $aDINIZ, F. M.
773 $tPeerJ$gv. 6, Article e4702, Apr. 2018.
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