117 research outputs found

    Gravitational field around a time-like current-carrying screwed cosmic string in scalar-tensor theories

    Full text link
    In this paper we obtain the space-time generated by a time-like current-carrying superconducting screwed cosmic string(TCSCS). This gravitational field is obtained in a modified scalar-tensor theory in the sense that torsion is taken into account. We show that this solution is comptible with a torsion field generated by the scalar field ϕ\phi . The analysis of gravitational effects of a TCSCS shows up that the torsion effects that appear in the physical frame of Jordan-Fierz can be described in a geometric form given by contorsion term plus a symmetric part which contains the scalar gradient. As an important application of this solution, we consider the linear perturbation method developed by Zel'dovich, investigate the accretion of cold dark matter due to the formation of wakes when a TCSCS moves with speed vv and discuss the role played by torsion. Our results are compared with those obtained for cosmic strings in the framework of scalar-tensor theories without taking torsion into account.Comment: 21 pages, no figures, Revised Version, presented at the "XXIV- Encontro Nacional de Fisica de Particulas e Campos ", Caxambu, MG, Brazil, to appear in Phys. Rev.

    Efeito da adição de sulfato de amônio sobre a produção de ácido succínico durante a fermentação alcoólica

    Get PDF
    Succinic acid production by yeasts during alcoholic fermentation of cane molasse supplemented with 25, 50 and 100 ppm of nitrogen in the form of ammonium sulfate was determined by gas-liquid chromatography. Ethanol production was not effected by the different levels of nitrogen, but there was a significant reduction in the content of succinic acid which was inversely related with the ammonium sulfate concentration in the medium.A produção de ácido succínico por leveduras durante a fermentação alcoólica de mosto de melaço suplementado com 25, 50 e 100 ppm de nitrogênio na forma de sulfato de amônio foi determinada por cromatografia em fase gasosa. A adição de nitrogênio amoniacal não afetou significativamente a produção de álcool etílico. Houve redução significativa no teor de ácido succínico com o aumento da quantidade de nitrogênio adicionada

    Efeito de reguladores de crescimento sobre os teores de ácido ascórbico e carboidratos solúveis de morango (Fragaria hybridus)

    Get PDF
    Several growth regulators were sprayed on strawberry plants: SADH (5000 ppm), CCC (2000 ppm), IAA (10 ppm, 3 times), GA 10 ppm, 3 times) and GA (550 ppm), Ascorbic acid, dry weight and soluble carbohydrates contents of fruits were determined. Statistically differences were not observed between treatments and control. Dry weight varied from 7.62 to 9.53%. Ascorbic acid content varied from 35.88 to 71.81 mg/100 g on fresh weight basis. Mean values of soluble carbohydrates, in grams/100 g on fresh weight basis, were total (5.58), sucrose (1.01), glucose (1.63) and frutose (1.54).Foram feitas aplicações dos seguintes reguladores de crescimento em morango (Fragarm hybridus): SADH a 5000 ppm, CCC a 2000 ppm, ATA a 10 ppm (3 aplicações), ácido giberélico a 10 ppm (3 aplicações) e 550 ppm. Análises de peso seco, ácido ascórbico e carboidratos solúveis dos frutos foram efetuadas a fim de se estudar o efeito desses reguladores de crescimento. Não foram detectadas diferenças significativas entre os diversas tratamentos e o controle. O peso seco variou de 7,62 a 9,53%. O conteúdo de ácido ascórbico variou de 35,88 a 71,81 mg/100 g de peso fresco. Os teores médios de carboidratos solúveis, expresso em g/100 g peso fresco, foram: totais (5,58), sacarose (1,01), glucose (1,63) e frutose (1,54)

    7th Drug hypersensitivity meeting: part two

    Get PDF
    No abstract availabl

    J/psi production as a function of charged-particle pseudorapidity density in p-Pb collisions at root s(NN)=5.02 TeV

    Get PDF
    We report measurements of the inclusive J/ψ yield and average transverse momentum as a function of charged-particle pseudorapidity density dNch/dη in p–Pb collisions at sNN=5.02TeV with ALICE at the LHC. The observables are normalised to their corresponding averages in non-single diffractive events. An increase of the normalised J/ψ yield with normalised dNch/dη, measured at mid-rapidity, is observed at mid-rapidity and backward rapidity. At forward rapidity, a saturation of the relative yield is observed for high charged-particle multiplicities. The normalised average transverse momentum at forward and backward rapidities increases with multiplicity at low multiplicities and saturates beyond moderate multiplicities. In addition, the forward-to-backward nuclear modification factor ratio is also reported, showing an increasing suppression of J/ψ production at forward rapidity with respect to backward rapidity for increasing charged-particle multiplicity
    corecore