1000 resultados para Estimativa populacional


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The aim of this study was to estimate the genetic parameters on a progeny test of Enterolobium contortisiliquum, located at the Fazenda Experimental de Luíz Antônio (IF-SP), São Paulo State, Brazil, for genetic selection and seed production. The coefficients of genetic variation and heritability, as well as the genetic and phenotypic correlations for the silvicultural traits diameter at breast height (DBH) and total height of plants at the age of 19, 20, and 21 years and bifurcation (BIF) and stem straightness (RET), at the age of 19 years were estimated. The F test of analysis of variance detected significant variation among the progeny for the traits DBH, height in the three tested ages, and straightness of the trunk, which indicates that the tested population can be improved by selection among progenies. The estimation of heritability at the level of progeny (h²m, minimum of 0.50) for all traits was high and at the levels of individual plants (h²i, minimum 0.18) and within progenies (h²d, minimum of 0.14) was medium, indicating that the population can be improved by selection among and within progenies. Significant high genetic and phenotypic correlations among pairwise growth traits of the same age were detected as well as among those with different ages. Therefore, the direct selection, of a trait allows indirect selection of another. The results showed the potential of this progeny test to enhance a seed orchard by selection and seed production for commercial and environmental reforestation plans.

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Poultry facilities must provide an environment that ensures thermal comfort allowing the animal to express its genetic potential for production; and new tools are being applied to measure the thermal comfort, especially thermal cameras. The objective of this study was to evaluate the association of the surface temperature of the birds with those from the facilities, and estimate the sensible heat transfer. For this, the thermal conditions of rearing in two aviaries with different ventilation systems, during the period of March to April 2011 were recorded. The aviaries were divided into six quadrants for the registration of surface temperatures obtained using an infrared thermal camera. In each quadrant the ambient temperature, relative humidity and wind velocity during the obtention of images were also recorded. It was observed that the surface temperatures of birds are associated with the surface temperature of the rearing facilities (side curtains, roof and litter). In aviary with negative pressure higher wind speeds compared to the conventional one were recorded and; therefore, allowed a higher sensible heat transfer by birds, suggesting that this provided better conditions for thermal comfort.

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Leaf area estimate may contribute to understand the relationships of interference among weeds and crops. The objective of this research was to obtain a mathematical equation to estimate the leaf area of Euphorbia heterophylla based on linear measures of the leaf blade. Correlation studies were carried out using the real leaf area and leaf length (C) and the maximum leaf width (L) of 200 leaf blades which were collected from several agroecosystems at Universidade Estadual Paulista in Jaboticabal, SP, Brazil. The evaluated statistic models were: linear Y = a + bx; simple linear Y = bx; geometric Y = ax b; and exponential Y = ab x. All of the evaluated models can be used for E. heterophylla leaf area estimation. The simple linear regression model is suggested using C*L and taking the linear coefficient equal to zero. Thus, an estimate of the leaf area of E. heterophylla can be obtained using the equation Af' = 0.6816*(C*L).

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The goal of this paper is to present a methodology for quality control of horizontal geodetic networks through robustness and covariance analysis. In the proposed methodology, the positional accuracy of each point is estimated by a possible bias in their position (based on robustness analysis), in addition to its own positional precision (uncertainty) (through covariance analysis), being a measure independently from the choice of the datum. Besides presenting the theoretical development of the method, its application is demonstrated in a numerical example. The results indicate that, in general, the greater the distance of an unknown point to the control(s) point(s) of the network, the greater is the propagation of random errors on this unknown point, and the smaller the number of redundant observations around a unknown point, the greater the influence of possible (undetected) non-random errors on this point.

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The objective of this study was to obtain a mathematical equation to estimate the leaf area of Panicum maximum using linear measures of leaf blade. Correlation studies were conducted involving the real leaf area (Sf), the main vein leaf length (C), and the maximum leaf width (L). The linear and geometric equations related to C provided good leaf area estimates. For practical reasons, the use of an equation involving only the C*L product is suggested. Thus, an estimate of P. maximum leaf area can be obtained by the equation Sf = 0.6058 (C*L), with the coefficient of determination R = 0.8586.

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The aim of this research was to estimate the skeletal growth and development by observingradiographically the morphological changes of the first, second and third cervical vertebrae, according to the method proposed by Hassel &Farman32 (1995) in patients who were going through the outbreak of pubertal growth. The radiographic inspection of the cervical vertebrae was performed by means of cephalometric radiographs and the outbreak of pubertal growth was identified through the events of ossification of the hand and wrist. For that purpose, we selected thecephalometric radiographs and hand•wrist radiographs of 110 Brazilianleukoderms, male and female,with chronological age ranging from 8 to 14,6 years old for the girls and from 9,5 to 15,4 years old for the boys.The results showed that there was a statistically significant correlation between the maturation indicators of the cervical vertebrae and the patients who were going through the outbreak of pubertal growth. The conclusion was that the radiographic evalution of the changes of the cervical vertebrae, in the cephalometric radiographs, is an alternative parameter, which is reliable and practical in the skeletal evalution, and the it completes the range of information that must be obtained from the patient under orthodontic treatment and that it can, circumstantially, replace other methods of evalution

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Pós-graduação em História - FCHS

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Lianas play a key role in many tropical forests ecosystems, contributing to community abundance, diversity and structure. Techniques to census lianas and estimate biomass have been used mainly in tropical forests. The aim of this study was to verify if different measurement location on the stem and inclusion criteria influence the estimations of liana abundance and biomass in Cerrado. The study was carried out at Itirapina fragment (ca 260 ha) located in Sao Paulo, Southeast Brazil. We measured all apparent ramets of rooted lianas by using different inclusion criteria: >= 0.5 cm in diameter at 30 cm basal area (D_30), and at 130 cm diameter breast height (DBH), in 36 transects (10 x 25 m). We compared the biomass using the allometric equation based on data from tropical florest take at 130 cm (DBH) and other The allometric biomass equation development to estimate the aboveground biomass of live lianas in tropical forests (DAP = 130 cm) was used. We tested the liana biomass, based on measurements taken at (D_30) using two different conversion equations. The results did not show significant differences in liana abundance and above ground biomass estimated applying the different criteria of inclusion However the biomass estimated from data collected at D_30 and converted into DAP showed a tendency to increase in biomass. Our findings suggest that the protocol used to the census of liana and the allometric biomass equation proposed to forests can be applied in the Cerrado.

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Currently new techniques for data processing, such as neural networks, fuzzy logic and hybrid systems are used to develop predictive models of complex systems and to estimate the desired parameters. In this article the use of an adaptive neuro fuzzy inference system was investigated to estimate the productivity of wheat, using a database of combination of the following treatments: five N doses (0, 50, 100, 150 and 200 kg ha(-1)), three sources (Entec, ammonium sulfate and urea), two application times of N (at sowing or at side-dressing) and two wheat cultivars (IAC 370 and E21), that were evaluated during two years in Selviria, Mato Grosso do Sul, Brazil. Through the input and output data, the system of adaptive neuro fuzzy inference learns, and then can estimate a new value of wheat yield with different N doses. The productivity prediciton error of wheat in function of five N doses, using a neuro fuzzy system, was smaller than that one obtained with a quadratic approximation. The results show that the neuro fuzzy system is a viable prediction model for estimating the wheat yield in function of N doses.

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The aims of this study was evaluated the efficiency of nitrogen sufficiency index (NSI) calculated with base on the measures relative chlorophyll index (RCI) leaves, measured with portable chlorophyll meter, as an indicator of time of sidedressing N fertilization and verify which value of NSI (90% and 95%) is the most appropriate to indicate the moment of N fertilization on common bean cultivar IAC Alvorada. An experiment with five N managements (M1: 200 kg ha(-1) N (40 kg at sowing + 80 kg at 15 days after emergency (DAE) + 80 kg 30 DAE); M2: 100 kg ha(-1) N (20 kg at sowing + 40 kg at 15 DAE + 40 kg at 30 DAE); M3: 20 kg ha(-1) N at sowing + 30 kg ha(-1) when chlorophyll meter readings indicated NSI < 95%; M4: 20 kg ha(-1) N at sowing + 30 kg N ha(-1) N when chlorophyll meter readings indicated NSI <90% and, M5: control (without N application)) and four replications was carried out in the rainy and dry growing seasons of the agricultural year 2009/10, in Botucatu, Sao Paulo State, Brazil. The variables RCI, aboveground dry matter, leaf N concentration, yield components, grain yield, and N use efficiency were evaluated. The NSI of 90%, calculated based on monitoring of RCI in common bean leaves with chlorophyll meter, was more effective than 95% to define need for N sidedressing in common bean cultivar IAC Alvorada, reducing the N application and improving the use efficiency of applied N.

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Pós-graduação em Agronomia (Produção Vegetal) - FCAV