Entre tradições e modernidade: conhecimento ecológico local, conflitos de pesca e manejo pesqueiro no rio Negro, Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Orientações nacionais para a reforma do ensino médio: dogma e liturgia

O estudo analisa criticamente os fundamentos das atuais diretrizes nacionais para o ensino médio brasileiro, dando especial enfoque à sua coerência com tendências mundiais e seus nexos com recomendações de agências internacionais para reformas educativas nos países emergentes. Discute, outrossim, as vicissitudes e peculiaridades do processo de formulação das referidas diretrizes e sugere o aprofundamento da discussão, indicando aspectos polêmicos que merecem maior reflexão.

O conceito de racionalidade em Habermas: a 'guinada lingüística' da teoria crítica

Este ensaio originalmente foi uma comunicação apresentada na UNICAMP. Foi escrito a propósito da visita de Habermas ao Brasil, esperada para o segundo semestre do ano passado. Seu objetivo imediato era fornecer algumas informações sobre as reflexões habermasianas mais recentes. Para isto, tentou-se inserir historicamente a proposta habermasiana de uma razão comunicativa no atual contexto de generalizada irrupção de formas discursivas fragmentárias relativistas e irracionalistas (o pós-estruturalismo francês e o pensiero debole italiano são os exemplos estudados). Sem pretender esgotar um tema tão complexo, tentou-se também levantar algumas questões sobre as possibilidades crítico-cognoscitivas da guinada linguística da filosofia de Habermas e de Apel.

Duas ou três coisas sobre Antonio Candido

Busca-se aqui investigar a conexão entre duas características definidoras da originalidade crítica de Antonio Candido: sua filiação à linhagem do marxismo ocidental e sua inserção numa tradição nacional.

Desenvolvimento larval de Eriphia gonagra (Fabricius, 1781) (Decapoda, Xanthidae), em laboratório

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estrutura de um trecho de floresta Amazônica na bacia do alto rio Xingu

Este estudo apresenta a estrutura de florestas em Gaúcha do Norte-MT (13° 10'S e 53° 15' O), na borda sul-amazônica. Para o levantamento fitossociológico, três áreas amostrais de 1ha foram subdivididas em 50 parcelas de 10x20m, nas quais foram amostrados todos os indivíduos com perímetro à altura do peito (PAP) >15 cm. Para verificar a similaridade estrutural entre as áreas utilizou-se a Análise de Correspondência. As espécies indicadoras dos ambientes de interflúvio e das áreas sujeitas à inundação foram obtidas através do TWINSPAN e de um sistema de pesos. Concluiu-se que as florestas presentes na bacia do rio Pacuneiro pertencem à mesma unidade fitogeográfica, mas com subtipos florísticos e estruturais de acordo com a posição no relevo, a proximidade dos cursos d'água e o estrato analisado, apresentando predominância de algumas espécies, ou até mesmo possíveis endemismos, em determinados trechos ou estratos. A formação apresentou baixa diversidade alfa (2,91 a 3,50) e beta (3,62 a 3,86), o que não é comum em florestas amazônicas. Várias hipóteses podem explicar essa baixa diversidade, entre elas a baixa precipitação e a alta sazonalidade, o ambiente físico regional aparentemente homogêneo e favorável às espécies competidoras, ou os eventos históricos, relacionados à possível exploração por tribos indígenas ou à recente expansão dessas florestas sobre as áreas savânicas.

Titi monkeys (Callicebus spp., Atelidae : Platyrrhini) in the Brazilian state of Rondonia

Five species of titi monkey (Callicebus brunneus, Callicebus caligatus, Callicebus cinerascens, Callicebus donacophilus, and Callicebus moloch) were recorded in surveys of primate populations at 26 sites throughout the Brazilian state of Rondonia. The distribution of the two species, C. cinerascens and C. donacophilus (recorded in the state for the first time), appeared to be related to that of non-forest ecosystems, the former in the cerrado woodlands, and the latter in gallery forests of the Guapore grasslands. The results of the surveys also indicate that C. brunneus has a more restricted distribution in southern Rondonia than was previously thought, whereas C. moloch is more widespread. However, the ecological factors that determine species distribution in the south of the state remain unclear on the basis of the available data. All species were observed in small social groups of no more than five individuals, which are typical of the genus, generally in the middle and lower forest strata.

An analysis of the floristic composition and diversity of Amazonian forests including those of the Guiana Shield

A large number of newly published and unpublished hectare plots in Amazonia and the Guiana Shield area allow an analysis of family composition and testing of hypotheses concerning alpha-diversity in the south American rain forest. Using data from 94 plots the family-level floristic patterns in wet tropical South America are described. To test diversity patterns, 268 plots are used in this large area. Contrary to a widely held belief, western Amazonian plots are not necessarily the most diverse. Several central Amazonian plots have equal or even higher tree diversity. Annual rainfall is not a good estimator for tree diversity in the Amazonia area and Guiana shield. Plots in the Guiana Shield area (and eastern Amazonia) usually have lower diversity than those in central or western Amazonia. It is argued that this is not because of low rainfall or low nutrient status of the soil but because of the small area of the relatively isolated rain forest area in eastern Amazonia and the Guiana Shield. The low diversity on nutrient-poor white sand soils in the Amazon basin is not necessarily due to their Low nutrient status but is, at least partly, caused by their small extent and fragmented nature.

Origins of sequence diversity in the malaria vaccine candidate merozoite surface protein-2 (MSP-2) in Amazonian isolates of Plasmodium falciparum

The recent evolution of Plasmodium falciparum is at odds with the extensive polymorphism found in most genes coding for antigens. Here, we examined the patterns and putative mechanisms of sequence diversification in the merozoite surface protein-2 (MSP-2), a major malarial repetitive surface antigen. We compared the msp-2 gene sequences from closely related clones derived from sympatric parasite isolates from Brazilian Amazonia and used microsatellite typing to examine, in these same clones, the haplotype background of chromosome 2, where msp-2 is located. We found examples of msp-2 sequence rearrangements putatively created by nonreciprocal recombinational events, such as replication slippage and gene conversion, while maintaining the chromosome haplotype. We conclude that these nonreciprocal recombination events may represent a major source of antigenic diversity in MSP-2 in P falciparum populations with low rates of classical meiotic recombination. (c) 2006 Elsevier B.V. All rights reserved.

Buffalos milk yield analysis using random regression models

Data comprising 1,719 milk yield records from 357 females (predominantly Murrah breed), daughters of 110 sires, with births from 1974 to 2004, obtained from the Programa de Melhoramento Genetic de Bubalinos (PROMEBUL) and from records of EMBRAPA Amazonia Oriental - EAO herd, located in Belem, Para, Brazil, were used to compare random regression models for estimating variance components and predicting breeding values of the sires. The data were analyzed by different models using the Legendre's polynomial functions from second to fourth orders. The random regression models included the effects of herd-year, month of parity date of the control; regression coefficients for age of females (in order to describe the fixed part of the lactation curve) and random regression coefficients related to the direct genetic and permanent environment effects. The comparisons among the models were based on the Akaike Infromation Criterion. The random effects regression model using third order Legendre's polynomials with four classes of the environmental effect were the one that best described the additive genetic variation in milk yield. The heritability estimates varied from 0.08 to 0.40. The genetic correlation between milk yields in younger ages was close to the unit, but in older ages it was low.

Mesoproterozoic rapakivi granites of the Rondonia Tin Province, southwestern border of the Amazonian craton, Brazil - I. Reconnaissance U-Pb geochronology and regional implications

Rapakivi granites and associated mafic and ultramafic rocks in the Rondonia Tin Province, southwestern Amazonian craton, Brazil were emplaced during six discrete episodes of magmatism between ca 1600 and 970 Ma. The seven rapakivi granite suites emplaced at this time were the Serra da Providencia Intrusive Suite (U-Pb ages between 1606 and 1532 Ma); Santo Antonio Intrusive Suite(U-Pb age 1406 Ma), Teotonio Intrusive Suite (U-Pb age 1387 Ma); Alto Candeias Intrusive Suite (U-Pb ages between 1346 and 1338 Ma); Sao Lourenco-Caripunas Intrusive Suite (U-Pb ages between 1314 and 1309 Ma); Santa Clara Intrusive Suite (U-Pb ages between 1082 and 1074 Ma); and Younger Granites of Rondonia (U-Pb ages between 998 and 974 Ma). The Serra da Providencia Intrusive Suite intruded the Paleoproterozoic (1.80 to 1.70 Ga) Rio Negro-Juruena crust whereas the other suites were emplaced into the 1.50 to 1.30 Ga Rondonia-San Ignacio crust. Their intrusion was contemporaneous with orogenic activity in other parts of the southwestern Amazonian craton, except for the oldest, Serra da Providencia Intrusive Suite. Orogenic events coeval with emplacement of the Serra da Providencia Intrusive Suite are not clearly recognized in the region. The Santo Antonio, Teotonio, Alto Candeias and Sao Lourenco-Caripunas Intrusive Suites are interpreted to represent extensional anorogenic magmatism associated with the terminal stages of the Rondonian-San Ignacio orogeny. At least the Sao Lourenco-Caripunas rapakivi granites and coeval intra-continental rift sedimentary rocks may, in contrast, represent the products of extensional tectonics and rifting preceding the Sunsas/Aguapei orogeny (1.25 to 1.0 Ga). The two youngest rapakivi suites, the Santa Clara Intrusive Suite and Younger Granites of Rondonia, seemingly represent inboard magmatism in the Rondonian-San Ignacio Province during a younger episode of reworking in the Rio Negro-Juruena Province during the waning stages of the collisional 1.1 to 1.0 Ga Sunsas/Aguapei orogeny. The six intra-plate rapakivi granite episodes in the southwestern part of the Amazonian craton form three broad periods of anorogenic magmatism that have age-correlative events composed of similar rocks and geologic environments in eastern Laurentia and Baltica, although the exact timing of magmatism appears slightly different. Recognition of lithologic and chronological correlations between various cratons provide important constraints to models explaining the interplay between rapakivi granite magmatism and deep crustal evolution of an early Mesoproterozoic supercontinent. They are, furthermore, important to plate tectonic models for the assembly, dispersal and reassembly of Amazonia, Laurentia and Baltica in the Mesoproterozoic and Neoproterozoic. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Roots, leaves and scapes anatomy of species of Paepalanthus subgenus Platycaulon (Eriocaulaceae)

The anatomical features of roots, leaves and scapes of the subgenus Platycaulon, genus Paepalanthus (Eriocaulaceae) that grow in the Brasilian rupestrian fields of Serra do Cipo - MG - Brazil were studied. The following main anatomical features were found: epidermis cells of varied thicknesses, chlorenchyma with compact or spread organization and leaf margin shape in the leaves; the scapes with continuous or discontinuous endodermis, divided or undivided pericycle, vascular bundles absent in the cortex and in the pith. These anatomical characteristics of the leaves and scapes occur in different species and can be used to separate them into Divise or Conferti sections. It was possible to confirm the proposed taxonomy based only on the morphological characteristics. Other anatomical features such as: presence or absence of air in the cortex roots and hypodermis which originate water parenchyma reserves in the mesophyll, can be an adaptative response that plants towards produce the environmental factors in this ecosystem.

A case study of convective organization into precipitating lines in the Southwest Amazon during the WETAMC and TRMM-LBA

A case study of convective development in the Southwest Amazon region during the Wet Season Atmospheric Mesoscale Campaign (WETAMC) and Tropical Rainfall Measuring Mission (TRMM)/Large-Scale Biosphere-Atmosphere (LBA) Experiment in Amazonia is presented. The convective development during 7 February 1999 is shown to occur during a period of very weak large-scale forcing in the presence of topography and deforestation. The available data include dual Doppler radar analysis, radiosonde launches, and surface and boundary layer observations. The observational analysis is complemented with a series of model simulations using the RAMS with 2-km resolution over a 300 km 300 km area forced by a morning radiosonde profile. A comparison of the observed and simulated thermodynamic transformation of the boundary layer and of the formation of convective lines, and of their kinematic and microphysical properties is presented. It is shown that only a few very deep and intense convective cells are necessary to explain the overall precipitating line formation and that discrete propagation and coupling with upper atmosphere circulations may explain the appearance of several lines. The numerical simulation indicates that topography may be the cause of initial convective development, although later on the convective line is parallel to the midlevel shear. There are indications that small-scale deforestation may have an effect on increasing rainfall in the wet season when the large-scale forcing is very weak.

Natural Conditions and Environmental Impacts in a Coastal Hydrographic Basin in the Brazilian Amazon

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)