Interação nitrogênio, fósforo, potássio na cultura da mandioca no Norte de Mato Grosso.

Na Região Norte do Estado de Mato Grosso, foram testadas doses de adubação fosfatada (0, 40, 80 e 120 kg de P2O5/ha) em interação com nitrogênio (o e 40 kg de N/ha) e potássio (0 e 40 kg de K2O/ha) para a cultura da mandioca, em dois ciclos de cultivo, de novembro/81 a marco/83, com a cultivar "Cuiabana", e de outubro/82 a fevereiro/84, com a cultivar "Juriti". Determinou-se a produção de folhas, hastes, cepa, raiz, número de plantas e porcentagem de amido. Não foram observados diferenças significativas entre tratamento para nenhuma das variáveis nos dois ciclos.bitstream/item/81260/1/interacao-nitrogenio-Laercio-Duarte-Boletim-Pesquisa-9-1992.pdfMemória

Estabilidade de agregados em latossolo vermelho-escuro da área experimental da Embrapa Meio Ambiente: subsídios aos estudos de avaliação do comportamento físico do solo na presença de lodo de esgoto.

O presente trabalho tem como objetivo principal avaliar o comportamento de agregados de um Latossolo Vermelho-Escuro da área experimental da Embrapa Meio Ambiente durante três anos, período em que serão aplicados dois tipos de lodo de esgoto em diferentes dosagens.bitstream/CNPMA/5856/1/estabilidade_de_agregados.pd

Experimental investigation of linear-optics-based quantum target detection

The development of new techniques to improve measurements is crucial for all sciences. By employing quantum systems as sensors to probe some physical property of interest allows the application of quantum resources, such as coherent superpositions and quantum correlations, to increase measurement precision. Here we experimentally investigate a scheme for quantum target detection based on linear optical measurment devices, when the object is immersed in unpolarized background light. By comparing the quantum (polarization-entangled photon pairs) and the classical (separable polarization states), we found that the quantum strategy provides us an improvement over the classical one in our experiment when the signal to noise ratio is greater than 1/40, or about 16dB of noise. This is in constrast to quantum target detection considering non-linear optical detection schemes, which have shown resilience to extreme amounts of noise. A theoretical model is developed which shows that, in this linear-optics context, the quantum strategy suffers from the contribution of multiple background photons. This effect does not appear in our classical scheme. By improving the two-photon detection electronics, it should be possible to achieve a polarization-based quantum advantage for a signal to noise ratio that is close to 1/400 for current technology.Comment: comments are welcome, submitted to PR

Structural properties of crumpled cream layers

The cream layer is a complex heterogeneous material of biological origin which forms spontaneously at the air-milk interface. Here, it is studied the crumpling of a single cream layer packing under its own weight at room temperature in three-dimensional space. The structure obtained in these circumstances has low volume fraction and anomalous fractal dimensions. Direct means and noninvasive NMR imaging technique are used to investigate the internal and external structure of these systems.Comment: 9 pages, 4 figures, accepted in J. Phys. D: Appl. Phy

Nutrientes vegetais no meio ambiente: ciclos bioquímicos, fertilizantes e corretivos.

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Grau de dependencia entre a leitura fibrografica a SL 2,5% e o comprimento comercial do algodao.

bitstream/item/33354/1/GRAU-DE-DEPENDENCIA.pd

Stochastic frontier approach to agricultural production including technical effects: the brazilian agricultural censures of 1995-1996 and 2006.

In this paper we analyze the impact of Embrapa’s research on the technical efficiencies of Brazilian farmers, particularly the poor. Using a stochastic frontier approach, we estimate a production function to obtain not only the technica efficiencies but also the elasticities of the key inputs. Our results indicate that Embrapa has generally had a positive effect on technical efficiencies, but there are still challenges ahead for Embrapa. Key among these challenges is the dissemination of its technology, which seems to be predominantly adopted by wealthier farmers. The low or absent use of modern inputs by poor farmers is highly detrimental of their ability to succeed

Assessing the determinants of rural income dispersion in Brazil.

This article has as its objective the analysis of rural income dispersion in Brazil. To this en we fit econometric regression models using the Gini index as the dependent variable, tecnology, and environmental, social and demographic indices as independent variables. The analysis is performed on a regional basis. The statistical approach uses fractional regression and generalized method of moments 9GMM) The tecnological variable crystallizes the production process uses county data collected from the Brazilian agricultural census of 2006. Tecnology is significant and dominates the relationship in all regions. The other covariates vary in regional intensity

Sequence diversity in coat protein of SCMV infecting maize and sorghum in Brazil.

The 'maize common mosaic', caused by potyvirus, is among the major virus diseases of this crop in Brazil. Although there were evidences indicating Sugarcane mosaic virus (SCMV) as the most common potyvirus species in maize (Zea mays L.) in Brazil, information about those species that infect sorghum plants [Sorghum bicolor(L.) Moench] are few. Leaves showing characteristic mosaic symptoms were collected from maize and sorghum and used in serological and sequencing analysis of the coat protein (CP) gene for potyvirus species identification. Amino acid (aa) analysis of the CP N-terminal sequence of our samples showed a different repeated sequence, a higher content of the dipeptide GT, and a 15 aa longer than the majority of the SCMV sequences used for comparisons. The Brazilian maize and sorghum potyviruses formed a monophyletic group, suggesting that they can be classified within a new SCMV strain. Studies using potyvirus CP gene sequencing from Brazilian sorghum potyvirus have been reported for the first time