130 resultados para probability and reinforcement proportion


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O objetivo deste trabalho foi verificar o efeito dos cortes efetuados a 0, 15, 30 e 45 cm sobre algumas características morfofisiológicas do Pennisetum purpureum, Schum. cv. Roxo nas épocas seca e chuvosa no Brejo Paraibano. As amostras foram obtidas de uma área útil de 8,4 m² de cada parcela. Após o corte de uniformização, efetuaram-se dois cortes no período seco, em intervalos de 90 dias, e três no período chuvoso, em intervalos de 60 dias. Foram avaliados os seguintes parâmetros: perfilhamento, altura das plantas, porcentagens de folhas e colmos e relação folha/colmo (RF/C). Aos 25 dias após cada corte, foram feitas as contagens dos perfilhos existentes nas parcelas. de cada parcela tomou-se uma amostra de 3 a 5 perfilhos, seca em estufa, e separaram-se as frações de folhas e colmos. Houve interação dos fatores (altura x época do corte) quanto ao número de perfilhos por m² e à RF/C. No período chuvoso, houve mais perfilhos basais que no período seco, e o número de perfilhos aéreo foi superior em todos os cortes acima do nível do solo. A RF/C foi superior na época chuvosa nas alturas de 30 e 45 cm do solo. Cortes mais altos apresentaram maior proporção de folhas e menor proporção de colmos. Os percentuais de folhas na época chuvosa foram maiores que os da época seca.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Employing the Feynman procedure of ordered exponential operators and the stationary phase method to evaluate the multiple integrals involved, we calculate the level-crossing probability and analyze the role of a resonance in the evolution of a two-level neutrino system. We compare this procedure with more conventional ones, such as Landau's method and the ansatz of Kuo and Pantaleone and Petcov. We verify that our results reproduce the correct extreme nonadiabatic limit and give the standard solutions in the adiabatic regime for any arbitrary matter density distributions. We discuss in particular the case of solar neutrino propagation using the standard solar model predictions for the matter distribution in the Sun.

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Bark extracts of Stryphnodendron adstringens (Mart) Coville a Leguminosae species, well known in Brazil as barbatimao, are popularly used as healing agent. The objective of this work was to determine the genetic diversity of S. adstringens populations and to correlate genetic distances to the production of tannins. S. adstringens accessions from populations found in Cerrado regions in the states of Goias, Minas Gerais and São Paulo were analyzed using the AFLP (Amplified Fragment Length Polymorphism) technique. A total of 236 polymorphic bands were scored and higher proportion of genetic diversity was found inter populations (70.9%), rather than intra populations (29.1%). F-ST value was found to be significantly greater than zero (0.2906), demonstrating the complex genetic structure of S. adstringens populations. Accessions collected in Cristalina, GO, showed higher percentage of polymorphic loci (87.3%) and the highest genetic diversity. The lowest genetic variability was detected among accessions from the population growing in Caldas Novas, GO. The genetic distance among populations was estimated using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), which grouped populations into 3 clusters. Moreover, chemotypes with tannin concentration above 40% showed higher genetic similarity. AFLP analysis proved to be an efficient gene mapping technique to determine the genetic diversity among remaining populations of S. adstringens. Obtained results may be employed to implement further strategies for the conservation of this medicinal plant. (C) 2011 Elsevier Ltd. All rights reserved.

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In this work, a series of transparent di-ureasil hybrids containing different amounts of methacrylic acid modified zirconium tetrapropoxide (ZrMcOH) nanoclusters (5-85 mol%) and incorporating EuCl3 and [Eu(tta)(3)(H2O)(2)](tta = thenoyltrifluoroacetonate) complex were prepared. These hybrids are multi-wave-length emitters due to the convolution of the host intrinsic emission (electron-hole recombinations occurring in siliceous and urea cross-linkages) Eu3+ intra-4f(6) transitions. The ZrMcOH incorporation deviates the maximum excitation wavelength of the hybrid host intrinsic emission from the UV (365 nm) to the blue (420 nm) and enhances the absolute emission quantum yield from 6.0 +/- 0.6% to 9.0 +/- 0.9%, and contributes to an increase in the D-5(0) lifetime values, quantum efficiency due to a decrease in the non-radiative transition probability and OH groups coordinated to the Eu3+ ions. (C) 2010 Elsevier B.V. All rights reserved.

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The castor bean plant is a tropical species and is subject to various diseases, which cause great losses. Among these diseases, the gray mold (Botryotinia ricini) is one of the most important. The fungus spore production was evaluated in the media of cultures BDA; Oats-Agar; Mazeina-Agar; Rice-Agar; castor-bean crushed leaves-agar (FM), FM-CaCO3; V8 juice to 5% (V8-5%); V8-10%; V8-20% and tomato juice at 5% (TJ-5%); TJ-10% and TJ-20%. The production of spore in different media of cultures was evaluated at 8(th) days of incubation. The data were analyzed using the comparison of means, through the test Tukey a 5% probability, and the data processed for (X + 1) (0.5). All means of crops tested were able to produce conidia, but the best results was obtained with the culture medium V8-20% (5.7 x 10(6) conidia/mL) and BDA (3.5 x 10(6) conidia/mL).

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Since 1988 to 1992, a study about susceptibility to antimicrobial drugs of bacterias isolated from hospitalized patients was performed. The compared susceptibility to important drugs (ampicillin, cephalotin, cefoxitin, ceftaxizime, ceftriaxone, aztreonam, gentamicin, amikacin, pefloxacin, ciprofloxacin, imipenem, oxacillin and vancomycin) was investigated in 1200 strains (300 of each specie) of the prevalent bacterias: E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and S. aureus. Minimal inhibitory concentration (MIC) was determined by agar dilution method, using from 0.05 to 256 mcg of each drug per ml of culture medium (Mueller-Hinton). Ranges of MIC, MIC(50%), MIC(90%) and the proportion of resistant strains were determined and permitted to know the 4 drugs that were found to be more active against bacterias; the CIM(90%) values are: E. coli - aztreonam (0.1 mcg/ml), pefloxacin (0.1), ceftazidime (0.25) and ceftriaxone (0.05); K. pneumoniae-aztreonam (0.25) ceftriaxone (0.25), ceftazidime (0.5) and pefloxacin (2.0); P. aeruginosa-imipenem (4.0), aztreonam (16), ceftazidime (16) and ciprofloxacin (16); S. aureus-vancomycin (1.01, ciprofloxacin (8, 0), amikacin (128) and cephalothin (128 mg/ml). The better 'in vitro' antibacterial activity observed was related to: aztreonam (77-100% of the sensitive strains), ceftazidime (50-99,7%), pefloxacin (73-99,7%), ciprofloxacin (80%), imipenem (93%) and vancomycin (100%).

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Since 1988 to 1992, a study about susceptibility to antimicrobial drugs of bacterias isolated from hospitalized patients was performed. The compared susceptibility to important drugs (ampicilin, cephalothin, cefoxitin, ceftazidime, ceftriaxone, aztreonam, gentamicin, amikacin, peftoxacin, ciprofloxacin, imipenem, oxacillin and vancomicin) was investigated in 1200 strains (300 of each specie) of the prevalent bacterias: E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and S. aureus. Minimal inhibitory concentration (MIC) was determined by agar dilution method, using from 0,05 to 256 mcg of each drug per ml of culture medium (Mueller-Hinton). Ranges of MIC, MIC 50%, MIC 90% and the proportion of resistant strains were determined and permited to know the 4 drugs that were found to be more active against bacterias; the CIM 90% values are: E. coli - aztreonam (0,1 mcg/ml), pefloxacin (0,1), ceftazidime (0,25) and ceftriaxone (0,05); K. pneumoniae - aztreonam (0,25), ceftriaxone (0,25), ceftazidime (0,5) and pefloxacin (2,0); P. aeruginosa - imipenem (4,0), aztreonam (16), ceftazidime (16) and ciprofloxacin (16); S. aureus - vancomicina (1,0), ciprofloxacin (8,0), arnicacina (128) and cephalothin (128 mg/ml). The better in vitro antibacterial activity observed was related to: aztreonam (77-100% of the sensitive strains), ceftazidime (50-99,7%), pefloxacin (73-99,7%), ciprofloxacin(80%), imipenem (93%) and vancomicin (100%).

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The objective of this study was to evaluate the in vitro activity of cefepime, cefpirome and amikacin against the most prevalent nosocomial bacteria. Initially a prospective study was designed to compare the bacterial susceptibility to the three drugs using 1,022 pathogenic strains. The strains were isolated from hospitalized patients of the Hospital das Clinicas - Faculdade de Medicina de Botucatu, SP, from March to December of 1996, by using the Bauer-Kirby susceptibility diffusion controlled method. The activity of cefepime by the Kirby-Bauer method was significantly higher (χ2, p ≤ 0.05) than cefpirome and amikacin for the following bacteria: P. aeruginosa (72% x 56% x 64%, respectively), Enterobacter cloacae (98% x 88% x 80%) and total strains (79.5% x 74.3% x 76.8%). Cefpirome exhibited higher activity than cefepime only to Enterococcus faecalis (42% x 23%). In the 12 other bacterial groups studied the sensibility of the three drugs was similar (χ2, p ≥ 0.05). The minimal inhibitory concentration (MIC) for 127 bacterial strains - Enterobacter cloacae (12), Citrobacter sp (15), Pseudomonas aeruginosa (50), Acinetobacter baumannii (12), BGNF others (22) and Enterococcus faecalis (16)-from the same origin previously described and isolated during 1997, was determined by E-test. Ranges of MIC intervals, MIC(50%), MIC(90%) and the proportion of the sensitive bacterial strains were determined and permitted the following analysis: the activity of cefepime against Gram-negative bacteria was 2 or more times higher than that of cefpirome and amikacin, specially when CIM(90%) was considered; the activity of cefpirome was higher only against E. faecalis. This information must be considered in the rational use of antibiotic, specially in patients with nosocomial infections.

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The present work evaluated urban forest indicators, acquired through airborne high-resolution multiespectral images, on the quality of the urban design and its vegetative fraction, in special its trees, in nine neighborhoods of Piracicaba, SP. There were made supervised classifications for characterization of intra-urban elements and the proportions obtained, as exposed soil, tree cover, lawns, asphalt, concrete pavements and roofs. They were studied for the measurement of the urban forest in each place. These variables were related to each other, as well as with the independent variables: population density, people with more than fifteen years of study and family heads with income above twenty minimum wages, obtained through population census. Through the analysis of linear regression variables were identified for intra-urban areas evaluation. Correlations were made and linear regressions among the data obtained from the image and among the proposed indicators. Negative correlations were obtained among population density and arboreal covering and the evaluated indices, in accordance with the predicted in the literature. Composite indicators are proposed, as: the proportion between arboreous space on waterproof space (PAW) and the proportion between arboreous space on building space (PAB). It is concluded by the possibility of the use of those indicators for evaluation of the urban forest and definition of priorities in the execution of ordinances to the improvement of the urban forestry, being prioritized the application of resources in the most lacking neighborhoods.

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The purpose of this study was to measure and verify the esthetic influence of the bilateral spaces between maxillary teeth and lip corners, called negative space (NS), during smile. The sample was comprised of 60 smile photographs obtained from 60 individuals (30 men and 30 women) aged 18 to 25 years old. Two orthodontists and two lay people evaluated these pictures regarding esthetics by a visual analogue scale. In each picture, the right and left NS were measured in millimeters and in proportion to the smile width (SW). Data were analyzed for statistical significance (P = .05). The mean NS of the sample was 6.68 ± 1.99 mm, and the NS proportion in relation to the SW was 9.6 ± 2.56%, for both sides of the arch. No significant asymmetries were observed between the right and left sides. The NS was significantly larger in men than in women when measured in millimeters (P = .028) (7.08 ± 2.24 mm in men vs 6.28 ± 1.62 mm in women), but the NS proportion to the SW was similar (9.94 ± 2.24% in men vs 9.26 ± 1.61% in women). When the 12 individuals with the smallest NS in proportion to SW were compared with the 12 individuals with the largest NS in proportion to SW, there was no statistical difference regarding the esthetic evaluation (P = .11). It was concluded that the NS did not influence the esthetic evaluation of smile photographs in the sample in this study, for both orthodontists and lay people. © 2006 by The EH Angle Education and Research Foundation, Inc.

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This article presents an exercise in meta-comprehension of what has been researched on teaching probability and statistics in Brazil. This research was based on the work on this subject presented in the third International Symposium for Research in Mathematics Education (III SIPEM). Articles were selected from the proceedings of the event analyzed hermeneuticly according to the procedures of phenomenology. We observed no evidence of clustering of research on this topic in terms of region or institutions, and we also emphasize that research on the teaching of Probability and Statistics needs to advance toward a theoretical discussion that transcends the subjects being studied and makes broader and deeper links between theory and practice. Findings also indicate that this sub-area of research in mathematics education is in the process of constituting itself.

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Aim: The present case report described the use of contact lens of thin porcelain veneers as a restorative therapy to solve anterior teeth disharmony. Background: Fragments of thin veneers are minimally invasive restorations with little or no dental preparation and present thickness ranging from 0.2 to 0.5 mm. They are used in case of diastema closure, small changes of teeth, color and restoration of teeth with small fractures. Case report: A 25-year-old man was admitted at a dental clinic complaining about the diastema presence on the upper anterior teeth. Patient was referred to an orthodontic treatment in order to provide better distribution of the diastemas and harmonious proportion of the teeth. Afterwards, contact lens of thin porcelain veneers were fabricated on the six upper anterior teeth. Conclusion: Based on the outcomes of this clinical report, we considered the use of fragments of thin veneers as a successful treatment option after 3 years of follow-up. Clinical significance: The fragments of thin veneers have been established to be an interesting alternative to esthetically restore the anterior teeth with minimal invasiveness. However, since it is a new treatment modality, longitudinal studies are necessary to understand the material's behavior.

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Insecticide potential and efficaciousness of vegetal extracts concentrations from six botanic families in three different modes were analyzed on the nymphs of the silverleaf whitefly Bemisia tabaci (Genn. 1889) on a tomato plantation Lycopersicon esculentum Mill. Nymph breeding was kept in cherry tomato shrubs. Test solutions were obtained from successive extractions with ethanol and evaporation in a rotary evaporator. Tests consisted of 10 solutions in four concentrations (500; 1,000; 1,500 and 3,000 μg/mL) and control treatment (distilled water + 1% DMSO) under three different modes of activity, namely, contact, translaminar and systemic. Experimental design was totally randomized with four repetitions and eleven treatments. Means were compared by Scott-Knott test at 5% probability and lethal concentrations (CL50) were calculated by POLO. In the case of contact activity mode, all extracts had efficiency above 50% with the highest concentration (3,000 μg/mL) in which the highest efficiency for all extracts tested was verified. There was a need for dose increase in translaminar activity mode for similar results, whereas in the case of systemic activity the best performance was obtained with extracts of Nerium oleander, Derris amazonica and Ipomoea carnea. Extracts of the last two caused a higher percentage when compared with that of other extracts in all activity modes lower than CL50.

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This paper presents a numerical approach to model the complex failure mechanisms that define the ultimate rotational capacity of reinforced concrete beams. The behavior in tension and compression is described by a constitutive damage model derived from a combination of two specific damage models [1]. The nonlinear behavior of the compressed region is treated by the compressive damage model based on the Drucker-Prager criterion written in terms of the effective stresses. The tensile damage model employs a failure criterion based on the strain energy associated with the positive part the effective stress tensor. This model is used to describe the behavior of very thin bands of strain localization, which are embedded in finite elements to represent multiple cracks that occur in the tensioned region [2]. The softening law establishes dissipation energy compatible with the fracture energy of the concrete. The reinforcing steel bars are modeled by truss elements with elastic-perfect plastic behavior. It is shown that the resulting approach is able to predict the different stages of the collapse mechanism of beams with distinct sizes and reinforcement ratios. The tensile damage model and the finite element embedded crack approach are able to describe the stiffness reduction due to concrete cracking in the tensile zone. The truss elements are able to reproduce the effects of steel yielding and, finally, the compressive damage model is able to describe the non-linear behavior of the compressive zone until the complete collapse of the beam due to crushing of concrete. The proposed approach is able to predict well the plastic rotation capacity of tested beams [3], including size-scale effects.