22,348 research outputs found

    Protocolo modificado para extração de DNA do gênero Pestalotiopsis.

    Get PDF
    Objetivou-se com este trabalho modificar o protocolo de extração de DNA do gênero Pestalotiopsis. Foram obtidos 200 mg de micélio de 11 isolados de Pestalotiopsis sp. O protocolo de extração proposto por Joshi (2009) foi modificado e testado retirando-se o fenol no processo de desproteinização do DNA. A quantidade de DNA genômico extraído foi quantificada em fotodocumentador e a qualidade do DNA final foi avaliada em gel 0,9% de agarose e em reações de marcadores RAPD. A metodologia sem o emprego do fenol proporcionou quantidade satisfatória (32,55 a 49,92 ng/µL) e pureza de DNA para caracterização molecular do fungo. O protocolo modificado, portanto, pode ser utilizado para extrair DNA do gênero Pestalotiopsis com eficiência do método e segurança para os usuários

    Adubação em pastagens degradadas de capim-colonião.

    Get PDF
    bitstream/item/64583/1/Altamira-PA3-81.pd

    Introdução e avaliação de plantas forrageiras.

    Get PDF
    bitstream/item/57837/1/Altamira-PA4.pd

    Cosmological constant constraints from observation-derived energy condition bounds and their application to bimetric massive gravity

    Full text link
    Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including different theories of gravity, with observational data. In this context, we use the ECs to probe any alternative theory whose extra term acts as a cosmological constant. For this purpose, we apply a model-independent approach to reconstruct the recent expansion of the universe. Using Type Ia supernova, baryon acoustic oscillations and cosmic-chronometer data, we perform a Markov Chain Monte Carlo analysis to put constraints on the effective cosmological constant Ωeff0\Omega^0_{\rm eff}. By imposing that the cosmological constant is the only component that possibly violates the ECs, we derive lower and upper bounds for its value. For instance, we obtain that 0.59<Ωeff0<0.910.59 < \Omega^0_{\rm eff} < 0.91 and 0.40<Ωeff0<0.930.40 < \Omega^0_{\rm eff} < 0.93 within, respectively, 1σ1\sigma and 3σ3\sigma confidence levels. In addition, about 30\% of the posterior distribution is incompatible with a cosmological constant, showing that this method can potentially rule it out as a mechanism for the accelerated expansion. We also study the consequence of these constraints for two particular formulations of the bimetric massive gravity. Namely, we consider the Visser's theory and the Hassan and Roses's massive gravity by choosing a background metric such that both theories mimic General Relativity with a cosmological constant. Using the Ωeff0\Omega^0_{\rm eff} observational bounds along with the upper bounds on the graviton mass we obtain constraints on the parameter spaces of both theories.Comment: 11 pages, 4 figures, 1 tabl

    Magnetic phases evolution in the LaMn1-xFexO3+y system

    Full text link
    We have investigated the crystal structure and magnetic properties for polycrystalline samples of LaMn1-xFexO3+y, in the whole range x=0.0 to x=1.0, prepared by solid state reaction in air. All samples show the ORT-2 orthorhombic structure that suppresses the Jahn-Teller distortion, thus favoring a ferromagnetic (FM) superexchange (SE) interaction between Mn^{3+}-O-Mn^{3+}. For x=0.0 the oxygen excess (y ~ 0.09) produces vacancies in the La and Mn sites and generates a fraction around 18% of Mn^{4+} ions and 82% of the usual Mn^{3+} ions, with possible double exchange interaction between them. The Fe doping in this system is known to produce only stable Fe^{3+} ions. We find an evolution from a fairly strong FM phase with a Curie temperature T_{C} ~ 160 K, for x=0.0, to an antiferromagnetic (AFM) phase with T_{N} = 790 K, for x=1.0, accompanied by clear signatures of a cluster-glass behavior. For intermediate Fe contents a mixed-phase state occurs, with a gradual decrease (increase) of the FM (AFM) phase, accompanied by a systematic transition broadening for 0.2 < x < 0.7. A model based on the expected exchange interaction among the various magnetic-ion types, accounts very well for the saturation-magnetization dependence on Fe doping.Comment: 27 pages, 9 figure

    Estrutura de uma floresta de terra firme na região de Marabá-PA: a posição do mogno em relação ás outras espécies da comunidade.

    Get PDF
    bitstream/item/39905/1/Com-Tec-22-Am-Oriental.pd

    Pé-duro: o boi do Piauí.

    Get PDF
    bitstream/CPAMN-2009-09/19688/1/peduro2.pd

    Experimental Observation of Quantum Correlations in Modular Variables

    Full text link
    We experimentally detect entanglement in modular position and momentum variables of photon pairs which have passed through DD-slit apertures. We first employ an entanglement criteria recently proposed in [Phys. Rev. Lett. {\bf 106}, 210501 (2011)], using variances of the modular variables. We then propose an entanglement witness for modular variables based on the Shannon entropy, and test it experimentally. Finally, we derive criteria for Einstein-Podolsky-Rosen-Steering correlations using variances and entropy functions. In both cases, the entropic criteria are more successful at identifying quantum correlations in our data.Comment: 7 pages, 4 figures, comments welcom
    corecore