662 research outputs found

    Acumulação de matéria seca e micronutrientes pela planta matriz da bananeira cv. prata (Musa AAB, subgrupo prata) em diferentes estådios de desenvolvimento

    Get PDF
    A field experiment was conducted with banana plant cultivar Prata, in Cambissolic soil, at EspĂ­rito Santo State, Brazil, to study the curve of growth and boron, zinc, copper uptake, removed and returned to the soil. Three mother plants were selected at twelve different development stages. Samples of leaf, petiole, pseudostem, rhizome, stalk, bud flower and fruit were taken. Dry matter weight and percentage of micronutrients were measured, and the collected data were ajusted in a regression program. The following conclusions were drawn up: boron, zinc and copper uptake are influenced by dry matter production, except Cu in the petiole; the uptake ratio is 5 Zn: 2,5 B: 1 Cu; a high amount of B, Za and Cu can be returned to the soil with plant management; in a rational program for micronutrients fertilizer, it is necessary to take into account the amount of nutrients exported at the fruit harvest, especially boron.Visando estabelecer a curva de crescimento da matĂ©ria seca, marcha de absorção, quantidade exportada e reciclada de boro, zinco e cobre, instalou-se um ensaio no Estado do EspĂ­rito Santo, em solo cambissĂłlico distrĂłfico com declividade mĂ©dia de 40%. Sorteou-se trĂȘs plantas matrizes, bimensalmente atĂ© 300 dias e mensalmente atĂ© 465 dias apĂłs o plantio, que foram separadas em folha, pecĂ­olo, pseudo-caule, rizoma, engaço, botĂŁo floral e fruto. Determinou-se a massa de matĂ©ria seca e o teor de micronutrientes destes ĂłrgĂŁos, cujos dados foram ajustados em programa de regressĂŁo, obtendo-se as curvas de acumulação de matĂ©ria seca e de absorção dos micronutrientes. Dos resultados conclui-se que: a absorção do boro, zinco e cobre pelos ĂłrgĂŁos estudados, acompanha a acumulação de matĂ©ria seca, exceto o cobre, no pecĂ­olo; 70% dos micronutrientes analisados sĂŁo absorvidos a partir de 240 dias apĂłs o plantio; ocorre uma razĂŁo de absorção de 5 Zn, 2,5 B, 1 Cu; podem ser exportados com a colheita cerca de 10% B, 5,5% Zn e 3% Cu

    AcĂșmulo de macronutrientes pela bananeira cv. prata em diferentes estĂĄdios de desenvolvimento

    Get PDF
    A field experiment was conducted with the banana plant Prata cultivar, in a Cambisol, in Cariacica, EspĂ­rito Santo State, Brazil, to study the major nutrient uptake, removal and return to the soil. Three mother (up to harvest), and ratoon plants (up to months after emergence) were selected at twelve and nine different development stages , respectively. Samples of leaf, petiole, pseudostem, rhyzome, stalk, bud flower and fruit were taken. Percentages of N, P, K, Ca and Mg, were measured. The following conclusions, for mother and ratoon plants, were drawn: a large amount of major nutrients are needed for vegetative development and yield; major nutrient uptake are influenced by dry matter production, except K in the petiole; the uptake ratio between the major nutrients is 20 K : 12N : 10Mg: :9 Ca : 1 P for the mother plant and of 26 .5K:8N :4.5Mg: : 4.5Ca:l P for the ratoon plant. A high amount of major nutrients can be returned to the soil with plant management. In a rational program of major nutrient fertilizer, it is necessary to take into account the amount of nutrients exported by harvest, especially N, P and K. The ratoon plant accumulated a larger amount of major nutrients than the mother plant.Visando estabelecer a marcha de absorção, quantidade exportada e reciclada de nitrogĂȘnio, fĂłsforo, potĂĄssio e cĂĄlcio na bananeira cultivar Prata, instalou-se um ensaio no Estado do EspĂ­rito Santo, em janeiro de 1980, em terreno com declividade mĂ©dia de 40% e solo cambissĂłlico distrĂłfico. Sorteou-se trĂȘs plantas matrizes do plantio atĂ© 465 dias apĂłs (colheita),sendo bimensal atĂ© 300 dias e mensal atĂ© o final, totalizando doze estĂĄdios de desenvolvimento, e trĂȘs plantas rebento, mensalmente, da emissĂŁo atĂ© 300 dias apĂłs, atingindo nove estĂĄdios. Cada bananeira foi dividida em folha, pecĂ­olo, pseudocaule, rizoma, engaço, botĂŁo floral e fruto para se analisar os macronutrientes. A partir dos dados coletados ajustou-se um programa de regressĂŁo e obteve-se as curvas de absorção de macronutrientes, cujos resultados permitiram concluir que, as plantas matriz e rebento: necessitam de expressivas quantidades de macronutrientes para desenvolver e produzir; apresentam uma absorção de macronutrientes que acompanha a matĂ©ria seca acumulada pelos ĂłrgĂŁos, exceto para o potĂĄssio no perĂ­odo; absorvem mais de setenta e cinco por cento de nitrogĂȘnio, fĂłsforo e potĂĄssio apĂłs o estĂĄdio de 180 dias e acima de setenta por cento do cĂĄlcio e magnĂ©sio, a partir de 240 e 120 dias; podem repor ao solo grande parte dos macronutrientes absorvidos; apresentam uma razĂŁo de absorção de macronutrientes de 20 K:12 N:10 Mg: 9 Ca: 1 P e de 26,5:8 N:4,5 Mg: 4,5 Ca: 1 P. Conclui-se ainda que: deve-se considerar a quantidade de macronutrientes exportados com a colheita e consumo dos frutos, principalmente nitrogĂȘnio, fĂłsforo e potĂĄssio, em um programa de adubação; a planta rebento acumula mais macronutrientes do que a planta matriz

    First observation of the decay Bˉs0→D0K∗0\bar{B}^0_s \to D^0 K^{*0} and a measurement of the ratio of branching fractions B(Bˉs0→D0K∗0)B(Bˉ0→D0ρ0)\frac{{\cal B}(\bar{B}^0_s \to D^0 K^{*0})}{{\cal B}(\bar{B}^0 \to D^0 \rho^0)}

    Get PDF
    The first observation of the decay Bˉs0→D0K∗0\bar{B}^0_s \to D^0 K^{*0} using pppp data collected by the LHCb detector at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 36 pb−1^{-1}, is reported. A signal of 34.4±6.834.4 \pm 6.8 events is obtained and the absence of signal is rejected with a statistical significance of more than nine standard deviations. The Bˉs0→D0K∗0\bar{B}^0_s \to D^0 K^{*0} branching fraction is measured relative to that of Bˉ0→D0ρ0\bar{B}^0 \to D^0 \rho^0: B(Bˉs0→D0K∗0)B(Bˉ0→D0ρ0)=1.48±0.34±0.15±0.12\frac{{\cal B}(\bar{B}^0_s \to D^0 K^{*0})}{{\cal B}(\bar{B}^0 \to D^0 \rho^0)} = 1.48 \pm 0.34 \pm 0.15 \pm 0.12, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the ratio of the B0B^0 and Bs0B^0_s hadronisation fractions.Comment: 10 pages, 3 figures, submitted to Phys. Lett. B; ISSN 0370-269

    DeficiĂȘncias minerais em plantas de bertalha ( Basella alba, L.)

    Get PDF
    Basella alba is used as a major food on the Amazon region, north Brazil for its high mineral and vitamins content. The purpose of the present work was: a) obtain a clear picture of the macronutrient deficiency; b) growth of the plants in function of (1); c) analyptical levels found in the leaves. Young Basella alba plants (bertalha in Portuguese) were cultivated in pots containing fine pure quartz and irrigated by percolation with different nutrient solutions lacking one of the element at the time. Clear cut symptoms were obtained for all macronutrients. Only the omission of nitrogen and potassium affect the dry matter production of plants. The range in dry matter for unhealthy and healthy leaves were: N% = 1.25--3-55; P% = 0.17-0.36; K% = 0.46-3.55; Ca% = 0,62-1.78; Mg% = 0.37-0.80; S% = 0.19-0.13.Plantas de bertalha (Basella alba, L.) INPA-1 foram cultivadas em casa de vegetação em quartzo moĂ­do, irrigadas com soluçÔes nutritivas conforme SARRUGE (1975) e submetidas aos seguintes tratamentos: completo, omissĂŁo de N, omissĂŁo de P, omissĂŁo de K, omissĂŁo de Ca, omissĂŁo de Mg e omissĂŁo de S, com o objetivo de: (a) obter sintomas de deficiĂȘncia dos ma cronutrientes; (b) analisar o crescimento das plantas atravĂ©s da produção de matĂ©ria seca; (c) determinar a concentração dos macronutrientes nas folhas e caules das plantas cultivadas nos diversos tratamentos. Os sintomas visuais de deficiĂȘncia foram identificados e descritos. As plantas foram coletadas e separadas em raiz, caule, folhas e determinaram-se os teores dos macronutrientes minerais neste material. Os resultados obtidos mostram: - os sintomas visuais de deficiĂȘncia sĂŁo bem definidos e de fĂĄcil caracterização para todos os nutrientes; - sĂł foi possĂ­vel detectar efeito na produção de matĂ©ria seca das folhas e caules para omissĂŁo de nitrogĂȘnio e para omissĂŁo de potĂĄssio nos caules; - os nĂ­veis de deficiĂȘncia e adequação obtidos nas folhas foram respectivamente: N% = 1,25 e 2,63; P% = 0,17 e 0,36; K% = 0,46 e 3,55; Ca% = 0,62e 1,78; Mg% = 0,37 e 0,80; s%= 0,19 e 0,23. - os nĂ­veis de deficiĂȘncia e adequação obtidos nos caules foram respectivamente: N% = 0,67 e 0,98; P% = 0,13 e 0,31; K% = 0,73 e 2,67; Ca% = 0,11 e 0,64; Mg% = 0,08 e 0,20; S% = 0,15 e 0,20

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

    Get PDF
    Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

    Get PDF
    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio
    • 

    corecore