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Caracterização da produtividade florestal e dos padrões de crescimento de Pinus taeda L. no sul do Brasil através de análise de tronco; Characterization of forest productivity and growth patterns of Pinus taeda L. in south of Brazil using bole analysis

Munhoz, Juliana Soares Biruel
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/04/2011 PT
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55.8%
Visando caracterizar a dinâmica de crescimento do Pinus taeda no sul do Brasil, este estudo teve os seguintes objetivos: i) determinar os principais fatores edafo-climáticos e do povoamento associados à ampla variação de produtividade da espécie; e ii) caracterizar padrões de crescimento e uniformidade, do plantio até 9 anos em diferentes regiões edafoclimáticas. Para isso, foram selecionadas 24 parcelas sem desbaste (700m²), com aproximadamente 1450 árvores ha-1, entre 8 a 10 anos de idade, do projeto PPPIB (Produtividade Potencial do Pinus no Brasil), as quais estão localizadas em Jaguariaíva-PR, Ponta Grossa-PR, Rio Negrinho-SC e Três Barras-SC. O clima destas regiões é temperado úmido, com precipitação média anual de 1477mm, com temperaturas máxima, média e mínima de 24,3ºC, 17,9ºC e 12,7ºC. Todas as variáveis biométricas foram determinadas através do banco de dados de inventário (2006-2009), dados de cubagem, análise de tronco (discos), de anéis de crescimento (baguetas) e massa específica aparente (densitometria de raios-X). Coletaram-se solos (0-20cm) nas parcelas de inventário, e obtiveram-se os dados climáticos de estações meteorológicas locais. Através das análises de disco determinaram-se os índices de sítio (idade base 10 anos)...

Population dynamics and secondary production of the cockle Cerastoderma edule (L.) in a backbarrier tidal flat in the Wadden Sea; Dinámica de población y producción secundaria del berberecho Cerastoderma edule (L.) en una zona intermareal del Mar de Wadden

Ramón, Montserrat
Fonte: Consejo Superior de Investigaciones Científicas (España) Publicador: Consejo Superior de Investigaciones Científicas (España)
Tipo: Artículo
ENG
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35.79%
[EN] The population biology of the bivalve Cerastoderma edule was studied by monthly sampling from April 1994 to September 1995 at Neuharlingersieler Nacken, a backbarrier tidal flat near Spiekeroog island (East Frisian Wadden Sea, North Sea). Four stations located along a tidal gradient from 56 to 80% immersion time were established in order to analyse cockle growth, mortality and production. The highest densities were recorded at the beginning of the study (1000-1250 ind. M-2) with an intense and progressive decrease through 1995. A spatial distribution pattern was observed during summer 1994, with juveniles (3-12 mm long) being found in the high intertidal whereas adults occurred along the middle and lower intertidal. Based on growth increment data from tagging-recapture experiments, the parameters of the von Bertalanffy growth curve were estimated to be: asymptotic length L∞= 40 mm, and growth constant K = 0.404 y-1. A growth ring was formed in summer (July-August 1994). Annual somatic production ranged between 38.16 and 59.33 g AFDW . m-2. y-1. Total mortality ranged between Z = 0.52 year-1 and Z = 3.03 year-1. The distribution of the population was affected by passive displacements of juvenile cockles from the upper part of the intertidal toward lower zones in combination with high mortality at the station farthest from the coast...

The role of the PDK1/PKB kinases in regulating neuronal survival and differentiation: characterization of the PDK1 K465E knock-in mice

Zurashvili, Tinatin
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2015 ENG
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15.72%
Neuronal cell death programmes are counteracted by survival signals during development in order to maintain the tissue homeostasis. Neuronal differentiation is a mechanism generating functionally integrated neuronal cells from their progenitors. These processes appear to be mediated via activation of the Ras/Raf/MAPK and the PI3K/PDK1/PKB signaling pathways and are associated with a selective increase in protein translation. Protein kinase B (PKB/Akt) is a serine/threonine protein kinase which is claimed to be the critical transducer for several extracellular signals provided by different neurotransmitters, growth factors and hormones that promote phosphoinositide 3-kinase (PI3K) activation. PI3K is a lipid kinase characterized by its ability to phosphorylate the 3-OH group in the inositol ring of phospholipids at the inner side of the plasma membrane to generate phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3 or PIP3), which is a potent second messenger. PKB regulation by its activator PDK1 precisely relies on a PtdIns(3,4,5)P3 binding domain, named Pleckstrin Homology domain (PH-domain). Both PDK1 and PKB are protein kinases of the AGC family containing PH-domains which mediate their recruitment to the plasma membrane, where PKB is activated by phosphorylation at two regulatory residues...

Transport and stirring induced by vortex formation

Shadden, S. C.; Katija, K.; Rosenfeld, M.; Marsden, J. E.; Dabiri, J. O.
Fonte: Instituto de Tecnologia da Califórnia Publicador: Instituto de Tecnologia da Califórnia
Tipo: Article; PeerReviewed Formato: application/pdf; other
Publicado em 25/12/2007
Relevância na Pesquisa
15.75%
The purpose of this study is to analyse the transport and stirring of fluid that occurs owing to the formation and growth of a laminar vortex ring. Experimental data was collected upstream and downstream of the exit plane of a piston-cylinder apparatus by particle-image velocimetry. This data was used to compute Lagrangian coherent structures to demonstrate how fluid is advected during the transient process of vortex ring formation. Similar computations were performed from computational fluid dynamics (CFD) data, which showed qualitative agreement with the experimental results, although the CFD data provides better resolution in the boundary layer of the cylinder. A parametric study is performed to demonstrate how varying the piston-stroke length-to-diameter ratio affects fluid entrainment during formation. Additionally, we study how regions of fluid are stirred together during vortex formation to help establish a quantitative understanding of the role of vortical flows in mixing. We show that identification of the flow geometry during vortex formation can aid in the determination of efficient stirring. We compare this framework with a traditional stirring metric and show that the framework presented in this paper is better suited for understanding stirring/mixing in transient flow problems. A movie is available with the online version of the paper.

A idade adulta do Eucalyptus saligna Smith em, Rio Claro Estado de São Paulo, determinada pelas dimensões das fibras; The old age of Eucalyptus saligna Smith, at São Paulo state, by fiber dimensions

Santos, Clóvis F. O.; Nogueira, Isaias Rangel
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; Formato: application/pdf
Publicado em 01/01/1971 POR
Relevância na Pesquisa
25.81%
O presente trabalho, faz parte de um plano de estudo em desenvolvimento, sôbre fibras lenhosas de Eucalyptus saligna, Smith no Departamento de Botânica (Disciplina Anatomia de Madeira) desde 1966. Nêle apresentamos os resultados da determinação da idade adulta do E. saligna em função da variação do comprimento e da espessura da parede das fibras nos diferentes anéis de crescimento do lenho, de duas árvores com mais de 20 anos de idade. Os resultados das mensurações microscópicas das fibras analisadas num setor apenas e em dois discos tomados ao nível do D.A.P., nos permite afirmar que nas condições do Hôrto de Rio Claro, as duas árvores atingiram a idade adulta entre o 9.º e 10.º anel de crescimento os quais corresponde respectivamente a idade de 9 e 10 anos. Os resultados apresentados nêste trabalho nos forneceu informações importantes para a continuação do plano em desenvolvimento, qual seja o estudo de outros fatôres (longa e curta duração) que afetam a estrutura e as características dos elementos constituintes do lenho que apresentam valor industrial.; The objetive of this study was to get some information about fiber length variation in the growth rings of Eucalyptus saligna, with 21 year old, which data could give the mature age of this plant at São Paulo States. Two disc from two plants were colected at the level of D. B. H. at Forest Experiment Station "Navarro de Andrade" at Rio Claro...