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O presente trabalho teve por objetivo o estudo morfoanatômico dos órgãos vegetativos de Piper hispidum, visando a estabelecer características marcantes para a sua identificação e auxiliar estudos taxonômicos e farmacobotânicos. O material vegetal fresco e fixado foi estudado segundo as técnicas usuais de corte e coloração, incluindo análise em MEV. Piper hispidum é um arbusto com caule cilíndrico, nodoso, verde claro, com folhas alternas, ovadas, de cor verde-escura na face adaxial e verde claro na abaxial. Dentre as características anatômicas importantes para sua identificação destacam-se: parênquima cortical da raiz apresentando grupos de esclereídes. Córtex caulinar com faixas descontínuas de colênquima do tipo angular e tecido vascular organizado em dois círculos descontínuos de feixes colaterais. A folha é dorsiventral, hipoestomática, com estômatos tetracíticos. Hipoderme adaxial descontínua e abaxial frouxa com número variável de camadas; tricomas tectores e glandulares ocorrem nas duas faces. Epiderme uniestratificada e idioblastos oleíferos ocorrem em todos os órgãos.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Noctilio leporinus (Chiroptera, Noctilionidae) has adaptations to piscivorous feeding habits, but also consumes crustaceans and insects. Between June 2005 and May 2006, bats were surveyed with mist nets during two evenings per month in the gallery forest of Corrego dos Tenentes, Pindorama, São Paulo State, Brazil. The objectives were to collect fecal samples and identify the fish species that were consumed by N. leporinus in this fragmented forest landscape. We documented two new fish species to its diet, the guppy Poecilia reticulata, Peters, 1859 and the "guaru" Phalloceros caudimaculatus (Hensel, 1868). Both fish species forage near the surface of water for insects and zooplankton, which is an area also utilized by N. leporinus when foraging for insects, crustaceans and fishs.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Some dynamical properties for a classical particle confined in an infinitely deep box of potential containing a periodically oscillating square well are studied. The dynamics of the system is described by using a two-dimensional non-linear area-preserving map for the variables energy and time. The phase space is mixed and the chaotic sea is described using scaling arguments. Scaling exponents are obtained as a function of all the control parameters, extending the previous results obtained in the literature. (c) 2012 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Some dynamical properties of a particle suffering the action of a generic drag force are obtained for a dissipative Fermi Acceleration model. The dissipation is introduced via a viscous drag force, like a gas, and is assumed to be proportional to a power of the velocity: F alpha -nu(gamma). The dynamics is described by a two-dimensional nonlinear area-contracting mapping obtained via the solution of Newton's second law of motion. We prove analytically that the decay of high energy is given by a continued fraction which recovers the following expressions: (i) linear for gamma = 1; (ii) exponential for gamma = 2; and (iii) second-degree polynomial type for gamma = 1.5. Our results are discussed for both the complete version and the simplified version. The procedure used in the present paper can be extended to many different kinds of system, including a class of billiards problems.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Estudou-se o reuso de água de um sistema composto por estação de tratamento de esgoto (ETE) com aeração prolongada e lodo ativado, e em uma estação compacta de tratamento de água (ECTA) de uma indústria metalúrgica. Os processos para obtenção da água de reuso foram: microbiológico e físico-químico. O esgoto doméstico foi bombeado para a ETE, onde houve formação de flocos biológicos e água clarificada. Avaliou-se a eficiência do processo microbiológico da ETE mediante a remoção de demanda bioquímica de oxigênio (DBO), demanda química de oxigênio (DQO) e sólidos sedimentáveis (SS). A eficiência do processo físico-químico de clarificação e desinfecção foi avaliada mediante análises de pH, turbidez, cor, contagem de bactérias heterotróficas aeróbias, cloro livre, dureza, alcalinidade, cloretos, sulfatos, sólidos totais dissolvidos (STD). Na água de reuso além desses parâmetros avaliou-se a toxicidade aguda ao microcrustáceo Daphnia similis.

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Synthesis and characterization of antimony tartrate used as a precursor of ceramic powders obtained by Pechini's method were carried out. Antimony tartrate was chosen as a substitute for the antimony citrate commonly used in this chemical processing, because of difficulties in preparing the citrate. FTIR and TGA/DTA analysis showed that antimony tartrate, H-2[Sb-2(C4H2O6)(2)]. forms a polymeric structure. The procedure described indicates that the antimony chelate obtained is adequate for Pechini's method.

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Ca(Zr0.05Ti0.95)O-3 (CZT) thin films were prepared by the polymeric precursor method by spin-coating process. The films were deposited on Pt(1 1 1)/Ti/SiO2/Si(1 0 0) substrates and annealed at 650 degrees C for 2,4, and 6 It in oxygen atmosphere. Structure and morphology of the CZT thin films were characterized by the X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM) and field-emission scanning electron microscopy (FEG-SEM). XRD revealed that the film is free of secondary phases and crystallizes in the orthorhombic structure. The annealing time influences the grain size, lattices parameter and in the film thickness. (c) 2006 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This work describes the synthesis, characterization, and the thermal behavior investigation of four palladium(II) complexes with general formulae [PdX(2)(mba)(2)], in which mba = N-methylbenzylamine and X = OAc(-) (1), Cl(-) (2), Br(-) (3) or I(-) (4). The complexes were characterized by elemental analysis, infrared vibrational spectroscopy, and (1)H nuclear magnetic resonance. The stoichiometry of the complexes was established by means of elemental analysis and thermogravimetry (TG). TG/DTA curves showed that the thermodecomposition of the four complexes occurred in 3-4 steps, leading to metallic palladium as final residue. The palladium content found in all curves was in agreement with the mass percentages calculated for the complexes. The following thermal stability sequence was found: 3 > 2 > 4 > 1. The geometry optimization of 1, 2, 3, and 4, calculated using the DFT/B3LYP method, yielded a slightly distorted square planar environment around the Pd(II) ion made by two anionic groups and two nitrogen atoms from the mba ligand (N1 and N2), in a trans-relationship.