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    A Description of the Sound System of Misiones Mbya

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    Misiones Mbya is an indigenous language of South America spoken by the Mbya people in the Province of Misiones, Argentina. Although there are several studies in the literature about the Brazilian variety of this language, the linguistic information available about Misiones Mbya is extremely scarce. In this thesis I present a segmental analysis of the language (individual vowels and consonants) and a prosodic analysis of nasal harmony based on field data collected in three different communities in Misiones. The segmental analysis shows that this variety is very similar to the Brazilian variety of the language with only a few exceptions. The prosodic analysis of nasal harmony indicates that nasality fades with distance. It is also shown that some methods for carrying out acoustic analysis of nasality can yield results which can be confounded with stress

    Solitonic lattice and Yukawa forces in the rare earth orthoferrite TbFeO3

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    The control of domains in ferroic devices lies at the heart of their potential for technological applications. Multiferroic materials offer another level of complexity as domains can be either or both of a ferroelectric and magnetic nature. Here we report the discovery of a novel magnetic state in the orthoferrite TbFeO3 using neutron diffraction under an applied magnetic field. This state has a very long incommensurate period ranging from 340 Angstrom at 3K to 2700 Angstrom at the lowest temperatures and exhibits an anomalously large number of higher-order harmonics, allowing us to identify it with the periodic array of sharp domain walls of Tb spins separated by many lattice constants. The Tb domain walls interact by exchanging spin waves propagating through the Fe magnetic sublattice. The resulting Yukawa-like force, familiar from particle physics, has a finite range that determines the period of the incommensurate state.Comment: 11 pages 14 figure

    The conservation of energy-momentum and the mass for the graviton

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    In this work we give special attention to the bimetric theory of gravitation with massive gravitons proposed by Visser in 1998. In his theory, a prior background metric is necessary to take in account the massive term. Although in the great part of the astrophysical studies the Minkowski metric is the best choice to the background metric, it is not possible to consider this metric in cosmology. In order to keep the Minkowski metric as background in this case, we suggest an interpretation of the energy-momentum conservation in Visser's theory, which is in accordance with the equivalence principle and recovers naturally the special relativity in the absence of gravitational sources. Although we do not present a general proof of our hypothesis we show its validity in the simple case of a plane and dust-dominated universe, in which the `massive term' appears like an extra contribution for the energy density.Comment: 9 pages, accepted for publishing in GR

    Qualidade pós-colheita de frutos de tomateiro orgânico, colhidos em diferentes estádios de maturação.

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    O objetivo desse trabalho foi avaliar as caracteristicas fisico-quimicas que determinam a qualidade do tomate orgânico colhidos em diferentes estádios de maturação de duas cultivares (San Vito e Duradoro).CD-ROM. Suplemento. Trabalho apresentado no 51. Congresso Brasileiro de Olericultura, Viçosa, MG
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