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1.
Rev. biol. trop ; 58(4): 1093-1114, dic. 2010. graf, tab
Article in English | LILACS | ID: lil-637985

ABSTRACT

Bibliometric studies have found that male researchers have their greatest productivity around the age of 40, that female researchers produce less than their male colleagues, that incentives for collaboration are slow to affect productivity and that, just like humans, research institutes become larger, less productive, more expensive to maintain and less able to raise money as they grow old. Almost invariably, these conclusions come from statistical studies of large numbers of European and American scientists, and there are practically no studies about tropical researchers. We present an in-depth analysis of the productivity of an internationally recognized tropical botanist and conservationist, Luis Diego Gómez Pignataro, based on the totality of his published work and on our own knowledge, as co-workers and friends, of the life frame in which that scientific output was produced. His life output departs from the expected pattern in that he had the highest productivity before reaching the expected peak productivity age, and that when he reached it his productivity fell and never recovered. Furthermore, marriage did not produce the expected fall in productivity. A close analysis of his life indicates that in the middle of his career he switched to intense teaching and conservation activities, and this better explains why his output of scientific research articles was low afterwards. This switch may occur in other tropical scientists. Rev. Biol. Trop. 58 (4): 1093-1114. Epub 2010 December 01.


Los estudios bibliométricos han encontrado que los investigadores de sexo masculino tienen su mayor productividad aproximadamente a los 40 años; que las investigadoras producen menos que sus colegas masculinos, que los incentivos para la colaboración tardan en aumentar la productividad y que, al igual que los seres humanos, los institutos de investigación se hacen más grandes, menos productivos, más costosos y menos capaces de recaudar dinero a medida que envejecen. Casi siempre, estas conclusiones provienen de estudios de un gran número de científicos europeos y estadounidenses, y prácticamente no hay estudios sobre los investigadores tropicales. Aquí presentamos un análisis detallado de la productividad de un botánico y conservacionista tropical reconocido internacionalmente, Luis Diego Gómez Pignataro, basado en la totalidad de su obra publicada y en nuestro propio conocimiento de su vida como compañeros de trabajo y amigos. Su vida se aparta del patrón esperado en que tuvo su mayor productividad en los primeros 20 años de carrera y produjo comparativamente poco en los siguientes 20 años. Además, el matrimonio no produjo el descenso esperado en su productividad. Justo a la mitad de su carrera se dedicó intensamente a actividades de enseñanza y conservación, lo que explica esa baja en su producción. Este patrón podría darse en otros científicos tropicales.


Subject(s)
Bibliometrics , Botany/statistics & numerical data , Publishing/statistics & numerical data , Research/statistics & numerical data , Tropical Climate
2.
Biol. Res ; 41(2): 137-141, 2008. tab, graf
Article in English | LILACS | ID: lil-495747

ABSTRACT

The purpose of this study was to carry out a bibliometric analysis of the articles published in Chile during 1987-2006 that were categorized into the Plant Science discipline by ISI. The data was extracted from the Web of Science datábase, obtaining a total of 911 articles for analysis. Almost half of the articles were the outcome of an international collaboration, the United States being the country with more collaborative links with Chile within this discipline. A list was made with the 10 most-cited articles and 10 most frequently used journals. The analysis showed that almost 50 percent of the articles were concentrated in 10 different journals. The number of articles produced each year revealed a steady growth in scientific production since 1987. This is probably related to the progressive interaction between industry and public-research institutions.


Subject(s)
Bibliometrics , Botany/statistics & numerical data , Plants , Periodicals as Topic/statistics & numerical data , Research/statistics & numerical data , Chile , Journal Impact Factor
3.
Biota neotrop. (Online, Ed. port.) ; 7(3): 217-223, 2007. ilus, tab
Article in Portuguese | LILACS | ID: lil-477690

ABSTRACT

A extensa área coberta pelo domínio amazônico e os recursos financeiros limitados para estudos da biodiversidade exigem programas de pesquisa que obtenham o máximo de informação com os menores custos. Com o objetivo de avaliar as conseqüências da redução do esforço amostral sobre a retenção da informação ecológica, testou-se como diferentes larguras de parcela afetam os resultados da relação entre variação ambiental e composição da comunidade de pteridófitas da Amazônia Central. Foram feitas medidas da inclinação do terreno, abertura do dossel e do teor de argila do solo, em 37 parcelas de floresta de terra-firme. Todos os indivíduos de pteridófitas foram identificados e mapeados com relação a três faixas de amostragem. Foram testados os efeitos das variáveis ambientais sobre a composição de pteridófitas em parcelas de 250 x 2,5 m e em sub-amostras com a largura da parcela reduzida. A redução de 2,5 para 1 m na largura da parcela (60 por cento de redução no esforço amostral) correspondeu a uma redução de 24 por cento no custo do projeto, considerado os custos das excursões à campo, e a uma redução no número de espécies amostradas de 52 para 44. A redução 2,5 para 2 m na largura da parcela causou redução de apenas duas (4 por cento) nas espécies amostradas e 8 por cento no custo do projeto. Para todas as larguras testadas, a composição da comunidade esteve associada ao teor de argila e não esteve associada à inclinação do terreno. O efeito de abertura de dossel sobre a composição de espécies de pteridófitas não foi coerente entre os diferentes tamanhos de amostra. Esta incoerência deve estar relacionada à importância relativamente menor da luz sobre a estruturação da comunidade. Concluímos que as amostras com menor tamanho foram suficientemente informativas para detectar os principais gradientes de composição e sua associação aos fatores ambientais. Isso permitiria a redução nos custos totais ou alocação de mais parcelas...


The large area covered by the Amazonian domain and the limited financial support for biodiversity studies demand efficient research programs. Aiming to evaluate the consequences of reduced sampling effort on the retention of ecological information, we tested how differences in plot width affect the perceived relationship between environmental variation and the composition of the pteridophyte community in Central Amazonia. Measures of slope, canopy openness and soil clay content were taken in 37 terra-firme forest plots. All pteridophyte individuals were identified and mapped according to three sample strips. We tested the effects of environmental variables on pteridophyte composition of 250 x 2.5 meters-plots and on sub-samples of reduced width. The reduction of plot width from 2.5 to 1 m (60 percent reduction in sampling effort) corresponded to a reduction of 24 percent of the project's costs concerning field work expenses. This would reduce the number of sampled species from 52 to 44. The reduction of 20 percent plot width (from 2.5 to 2 m) would cause a reduction of two (4 percent) sampled species and a reduction of 8 percent of the costs. For all tested plot widths, community composition was associated with soil clay content and was not associated with the terrain slope. The effect of canopy openness on pteridophyte species composition was not consistent among sample sizes. These may be related to the relatively lower importance of light availability in determining community structure at the studied spatial scale. We concluded that the smallest plots were informative enough to detect the main gradients of composition and their association to environmental factors. This would allow a reduction in total costs, or the allocation of available budget to more plots, which could increase the power of the statistical analyses, reduce the confidence intervals and increase probability of detecting more species.


Subject(s)
Biodiversity , Botany/classification , Botany/economics , Botany/statistics & numerical data , Classification , Ecology/classification , Plants/classification
4.
Biota neotrop. (Online, Ed. port.) ; 7(3): 373-377, 2007. ilus
Article in Portuguese | LILACS | ID: lil-477707

ABSTRACT

Sinningia gigantifolia Chautems é uma espécie rupícola restrita à Serra da Mantiqueira e partes altas da Serra do Mar, que ocorre principalmente em formações florestais. O presente trabalho apresenta o primeiro registro desta espécie para o Estado de São Paulo, na Serra do Baú, em São Bento do Sapucaí. Uma descrição completa da espécie, uma análise da sua distribuição e uma alteração na chave de identificação do gênero Sinningia da Flora Fanerogâmica do Estado de São Paulo são fornecidas.


Sinningia gigantifolia Chautems is a rupicolous species restricted to the Serra da Mantiqueira and higher parts of the Serra do Mar in SE Brazil, ocurring mainly in forest formations. This note presents the first record of this species for São Paulo State, from the Serra do Baú, in São Bento do Sapucaí. A full species description, an analysis of its distribution and a revised key to the genus Sinningia for the Flora Fanerogâmica do Estado de São Paulo are provided.


Subject(s)
Biodiversity , Botany/classification , Botany/statistics & numerical data , Flora/analysis , Flora/classification , Flowers/classification , Flowers/adverse effects
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