999 resultados para southeast Brazil
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Although snake infralabial glands are generally constituted of mucous cells, among dipsadines, they are much more developed and predominantly serous in nature, possibly due to the peculiar feeding habits of some species of this group, the ""goo-eaters"", which feed on soft and viscous invertebrates. We compared the morphology and histochemistry of the infralabial glands of three goo-eater species of Southeast Brazil, Atractus reticulatus, Dipsas indica and Sibynomorphus mikanii. In A. reticulatus the glands are formed by mixed acini composed of mucous and seromucous cells and in D. indica, they are composed of mucous tubules and seromucous acini. In S. mikanii the glands are organized in seromucous acini; mucous cells are restricted to the gland anterior region and to the duct lining epithelium. Ultrastructurally, secretory granule electron density varies from low to moderate, depending on their mucous or seromucous nature. The results indicate a large morphological and histochemical variation in the infralabial glands, probably reflecting differences in the secretion chemical composition and in feeding specialization among the three species. The protein content in the secretory cells can be related with the presence of toxins that can be used in chemical prey immobilization or detaching of snails from their shells. (c) 2007 Elsevier Ltd. All rights reserved.
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Populations of Synchaeta jollyae (Shiel & Koste, 1993) (Rotifera), a species recently recorded for the first time in Brazil and South America, were analyzed in reservoirs in Southeast Brazil. Sampling was carried out monthly from August 2006 to July 2007 at Furnas Reservoir in the Rio Grande basin, state of Minas Gerais, and in four cascade reservoirs in the Tiete River basin (Barra Bonita, Bariri, Ibitinga and Nova Avanhandava) state of Sao Paulo, in June and September 2008 and in January and May 2009. Synchaeta jollyae occurred in most samples and periods. From the results obtained it is evident that S. jollyae occurs in water bodies of varied trophic status but reaches larger populations in eutrophic water bodies and during lower temperature periods. The greatest densities of S. jollyae were found in the eutrophic Bariri Reservoir, on the Tiete River, during the winter. Mann-Whitney test confirmed the significant difference between the population densities in periods of high and low temperatures, with populations reaching higher densities at lower temperatures. It is not yet possible to tell whether S. jollyae is a widely distributed species that has been overlooked in previous plankton studies in South America. Wherever these populations of S. jollyae might have originated, it appears to be a species well established and adapted to a wide range of conditions in the Neotropics.
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Scientists predict that global agricultural lands will expand over the next few decades due to increasing demands for food production and an exponential increase in crop-based biofuel production. These changes in land use will greatly impact biogeochemical and biogeophysical cycles across the globe. It is therefore important to develop models that can accurately simulate the interactions between the atmosphere and important crops. In this study, we develop and validate a new process-based sugarcane model (included as a module within the Agro-IBIS dynamic agro-ecosystem model) which can be applied at multiple spatial scales. At site level, the model systematically under/overestimated the daily sensible/latent heat flux (by -10.5% and 14.8%, H and E, respectively) when compared against the micrometeorological observations from southeast Brazil. The model underestimated ET (relative bias between -10.1% and 12.5%) when compared against an agro-meteorological field experiment from northeast Australia. At the regional level, the model accurately simulated average yield for the four largest mesoregions (clusters of municipalities) in the state of Sao Paulo, Brazil, over a period of 16 years, with a yield relative bias of -0.68% to 1.08%. Finally, the simulated annual average sugarcane yield over 31 years for the state of Louisiana (US) had a low relative bias (-2.67%), but exhibited a lower interannual variability than the observed yields.
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This study extends the current knowledge regarding the use of plants for the passive accumulation of anthropogenic PAHs that are present in the atmospheric total suspended particles (TSP) in the tropics and sub-tropics. It is of major relevance because the anthropic emissions of TSP containing PAHs are significant in these regions, but their monitoring is still scarce. We compared the biomonitor efficiency of Lolium multiflorum 'Lema' and tropical tree species (Tibouchina pukka and Psidium guajava 'Paluma') that were growing in an intensely TSP-polluted site in Cubatao (SE Brazil), and established the species with the highest potential for alternative monitoring of PAHs. PAHs present in the TSP indicated that the region is impacted by various emission sources. L. multiflorum showed a greater efficiency for the accumulation of PAH compounds on their leaves than the tropical trees. The linear regression between the logBCF and logKoa revealed that L. multiflorum is an efficient biomonitor of the profile of light and heavy PAHs present in the particulate phase of the atmosphere during dry weather and mild temperatures. The grass should be used only for indicating the PAHs with higher molecular weight in warmer and wetter periods. (C) 2012 Elsevier Inc. All rights reserved.
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The evapotranspiration (E) from a sugarcane plantation in the southeast Brazil was measured by the eddy-covariance method during two consecutive cycles. These represented the second (393 similar to days) and third year (374 similar to days) re-growth (ratoon). The total E in the first cycle was 829 similar to mm, accounting for 69% of rainfall, whereas in the second cycle, it was 690 similar to mm, despite the total rainfall (1353 similar to mm) being 13% greater. The ratio of E to available energy, the evaporative fraction, exhibited a smaller variation between the first and second cycles: 0.58 and 0.51, respectively. The estimated interception losses were 88 and 90 similar to mm, respectively, accounting for approximately 7% of the total rainfall. The sugarcane yield in the second cycle (61.5 similar to +/-similar to 4.0 similar to t similar to ha-1) was 26% lower than the first cycle, as well as lower than the regional average for the third ratoon (76 similar to t similar to ha-1). The below average yield was associated with less available soil water at the beginning of the cycle, with the amount of rainfall recorded during the first 120 similar to days of re-growth in the second cycle being 16% of that recorded in the first (203 similar to mm).
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Immatures of the Phelypera schuppeli (Boheman, 1834) (Curculionidae; Hyperinae; Cepurini) are described, illustrated and compared with available descriptions of larvae and pupae of Hyperini. Immatures and adults from midwest (Dourados, Mato Grosso do Sul; Pirenopolis, Goias) and southeast Brazil (Bauru, Sao Paulo) were found on leaves of the host plant, Pachira aquatica Aubl. (Malvaceae, formerly Bombacaceae), a tree used as an ornamental plant in many Brazilian frost-free cities. Larvae of P. schuppeli are exophytic, brightly colored, eruciform and possess abdominal ambulatory ampullae, resembling larvae of Lepidoptera. Mature larvae can spin globular lattice-like cocoons where pupation takes place. Data in the field and under laboratory conditions confirmed previously published biological observations on P. schuppeli. Additional information about defensive behaviors, process of cocoon construction and natural enemies, such as the larval predator Supputius cinticeps (Stal, 1860) (Hemiptera: Pentatomidae) and the prepupal and pupal parasitoid Jaliscoa nudipennis Boucek, 1993 (Hymenoptera: Pteromalidae), are reported.
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Questions Does the spatial association between isolated adult trees and understorey plants change along a gradient of sand dunes? Does this association depend on the life form of the understorey plant? Location Coastal sand dunes, southeast Brazil. Methods We recorded the occurrence of understorey plant species in 100 paired 0.25 m2 plots under adult trees and in adjacent treeless sites along an environmental gradient from beach to inland. Occurrence probabilities were modelled as a function of the fixed variables of the presence of a neighbour, distance from the seashore and life form, and a random variable, the block (i.e. the pair of plots). Generalized linear mixed models (GLMM) were fitted in a backward step-wise procedure using Akaike's information criterion (AIC) for model selection. Results The occurrence of understorey plants was affected by the presence of an adult tree neighbour, but the effect varied with the life form of the understorey species. Positive spatial association was found between isolated adult neighbour and young trees, whereas a negative association was found for shrubs. Moreover, a neutral association was found for lianas, whereas for herbs the effect of the presence of an adult neighbour ranged from neutral to negative, depended on the subgroup considered. The strength of the negative association with forbs increased with distance from the seashore. However, for the other life forms, the associational pattern with adult trees did not change along the gradient. Conclusions For most of the understorey life forms there is no evidence that the spatial association between isolated adult trees and understorey plants changes with the distance from the seashore, as predicted by the stress gradient hypothesis, a common hypothesis in the literature about facilitation in plant communities. Furthermore, the positive spatial association between isolated adult trees and young trees identified along the entire gradient studied indicates a positive feedback that explains the transition from open vegetation to forest in subtropical coastal dune environments.
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The aim of the present study was to characterize the variation of the chemical profiles among workers in different colonies of the stingless bee Melipona marginata. We used gas chromatography and mass spectrometry (CG-MS) and multivariate analysis of the bees' chemical from three colonies of two localities in southeast Brazil. The results showed that cuticular hydrocarbon profiles clearly separated distinct colonies. We show here the importance of using the chemical analyses for characterization of colony membership, in addition of the traditional techniques of diversity analyses.
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Baccharis compreende ca. 340 espécies distribuídas nas Américas. O indumento em tufos diminutos, formado por tricomas com uma única célula basal, e as flores funcionalmente unissexuais são caracteres diagnósticos do gênero. No estado do Rio de Janeiro ocorrem 55 espécies de Baccharis. O trabalho apresenta os resultados de estudos taxonômicos de Baccharis subgen. Molina (Pers.) Heering para a flora fluminense. No estado, o subgênero está representado por 18 espécies pertencentes a quatro seções - Caulopterae (8 spp.), Molinae (4 spp.), Baccharidastrum (3 spp.) e Trinervatae (3 spp.). É apresentada uma chave para a identificação das seções e espécies e descrições morfológicas, ilustrações, dados de distribuição geográfica e ecologia. Três espécies são novos registros e cinco são excluídas da lista de espécies do Rio de Janeiro.
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Histological and ultrastructural analyses of gills were observed in Nile tilapia collected from three different waterbodies in southeast Brazil: an urban lake in a park in the city of São Paulo, a reservoir in a rural city, and a commercial aquaculture facility. These aterbodies were analyzed and classified as hypereutrophic, eutrophic, and supereutrophic, respectively, with 310.00, 94.00, 28.00 of phosphate (PO2_ 4 lg L _1) and 65.49, 24.95, 12.83 of chlorophyll (lg L _1). A significant difference in the histological alterations index (HAI) was observed only in fish from the urban lake, with the presence of cell hypertrophy, hyperplasia, aneurism, and other alterations. When compared to the other groups, a large quantity of rodlet cells was also observed in the urban group. These results demonstrate the correlation of eutrophic states of water with gill morphology. Also discussed is the premise that large amounts of organic material dissolved in water can alter the morphology of the fish gills
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Esta dissertação teve como objetivo geral analisar as relações entre estilos de liderança, percepção de suporte organizacional e comprometimento organizacional afetivo em trabalhadores. Participaram da pesquisa 263 trabalhadores que atuam na Região Sudeste do Brasil (Rio de Janeiro e São Paulo) em organizações não governamentais, públicas e privadas. Como instrumento para coleta de dados foi utilizado um questionário de autopreenchimento composto de três escalas que mediram as variáveis da pesquisa. O estudo se propôs a apresentar, interpretar e discutir as relações entre as variáveis, como também, testar as hipóteses referentes ao modelo conceitual proposto, por meio de uma pesquisa de natureza transversal com abordagem quantitativa, cujos dados coletados foram analisados por aplicação de técnicas estatísticas paramétricas (cálculos de estatísticas descritivas: médias, desvio padrão, teste t e correlações; cálculos de estatísticas multivariadas: análises de regressões lineares múltiplas hierárquicas). O tratamento e análise dos dados foram realizados pelo software estatístico Statistical Package for the Social Science SPSS, versão 18.0 para Windows. Os resultados obtidos demonstraram que a variável percepção de suporte organizacional exerce forte e significativo impacto sobre comprometimento organizacional afetivo, enquanto que a variável estilos de liderança não consegue aumentar nem diminuir a força. A pesquisa possibilitou concluir pela adequação parcial do modelo testado visto ser a variável estilos de liderança um moderador frágil da relação entre percepção de suporte organizacional e comprometimento organizacional afetivo.
Resumo:
O objetivo geral deste estudo foi analisar, interpretar e discutir as relações entre as percepções de sucesso na carreira, bem-estar no trabalho e a intenção de rotatividade em trabalhadores da Região Sudeste do Brasil. Participaram desta pesquisa 500 trabalhadores que atuam no estado de São Paulo em organizações não governamentais, públicas e privadas. Como instrumento para coleta de dados foi utilizado um questionário de autopreenchimento composto de cinco escalas que mediram as variáveis da pesquisa. A presente pesquisa se propôs a apresentar, interpretar e discutir as relações entre as variáveis, como também, testar as hipóteses referentes ao modelo conceitual proposto, por meio de uma pesquisa de natureza transversal com abordagem quantitativa, cujos dados coletados foram analisados por aplicação de técnicas estatísticas paramétricas (cálculos de estatísticas descritivas: médias, desvio padrão, teste t e correlações; cálculos de estatísticas multivariadas: análise de regressão linear múltipla stepwise e teste da normalidade das variáveis, por meio do teste de Kolmogorov-Smirnov). O tratamento e análise dos dados foram realizados pelo software estatístico Statistical Package for the Social Science SPSS, versão 18.0 para Windows. Os resultados obtidos demonstraram que as dimensões de bem-estar no trabalho exercem forte e significativo impacto sobre a intenção de rotatividade dos profissionais, enquanto que a percepção de sucesso na carreira contribuiu com valores baixos neste impacto, devido ao formato do modelo hipotético. A pesquisa possibilitou concluir que quanto mais a empresa se preocupa em proporcionar um ambiente de trabalho que seja animador, interessante e que cause entusiasmo, menos os profissionais pensarão em deixá-la.
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Agroforestry systems with eucalyptus prevail in Central and Southeast Brazil, and little information is available about systems using native trees. The aim of the present study was to evaluate the development of seven native tree species grown under two agroforestry systems. The experiment was conducted starting in 2007 in 12-hectare area in the municipality of São Carlos, São Paulo state, Brazil. The tree species planted in the two systems (a silvopastoral system and an agrisilvicultural system) were: 'capixingui' (Croton floribundus) and 'mutambo' (Guazuma ulmifolia) (tutors), 'jequitibá-branco' (Cariniana estrellensis), 'canafistula' (Peltophorum dubium) and 'ipê felpudo' (Zeyheria tuberculosa) (timber trees), and 'angico-branco' (Anadenanthera colubrina) and 'pau-jacaré' (Piptadenia gonoacantha) (N-fixing trees). Data were collected for 48 months. The results show differences among tree development, which was evaluated as growth in height and diameter, as well as sensitivity to insect and disease damage. The overall results show that the agrisilvicultural system allowed better tree development. The species with best performance in the two systems were capixingui, mutambo and canafístula. Ipê-felpudo and jequitibá-branco showed the worst results. The high variability among individuals of the same species indicates the possibility of high production advances with selective breeding of these species.
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Allele frequency distributions and population data for 12 Y-chromosomal short tandem repeats (STRs) included in the PowerPlex (R) Y Systems (Promega) were obtained for a sample of 200 healthy unrelated males living in S (a) over tildeo Paulo State (Southeast of Brazil). A total of 192 haplotypes were identified, of which 184 were unique and 8 were found in 2 individuals. The average gene diversity of the 12 Y-STR was 0.6746 and the haplotype diversity was 0.9996. Pairwise analysis confirmed that our population is more similar with the Italy, North Portugal and Spain, being more distant of the Japan. (c) 2007 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Paracoccidioidomycosis has been known for over 100 years, and until now, there were only few estimates of the disease`s incidence. We aim to analyze 1,000 cases treated between 1960 and 1999 at Ribeirao Preto city, Sao Paulo, Brazil, where the disease`s incidence range detected was 1.6 to 3.7 cases per 100,000 habitants per year (mean = 2.7 cases/year). We observed a male to female ratio of 6:1 and an age distribution from 3 to 85 years. The acute/subacute form of the disease accounted for 25.4% of cases. Most of the patients (93.5%) had lived or worked in rural areas before the disease development. Smoking and alcoholism were reported by 64.7% and 37.2% of patients, respectively. Comorbidities identified included tuberculosis (8.3%), Chagas` disease (8.6%), and human immunodeficiency virus/acquired immunodeficiency syndrome (4.2%). The present study revealed an area in Brazil where paracoccidioidomycosis is hyperendemic (has the highest reported incidence of this disease); this endemic area is probably caused by geological and climatic conditions as well as intensive agriculture.