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

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

Effectiveness of physiotherapy intervention on the quality of life of women with breast cancer who underwent sentinel lymph node biopsy

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Birth weight and heart rate autonomic recovery following exercise in healthy term-born adults

The impact of birth weight (BW) on adult health has been studied, related to the autonomic nervous system, and implicated in cardiovascular risk. We investigated cardiorespiratory and heart rate (HR) autonomic recovery after moderate effort in healthy term-born adults with different BWs. We studied 28 healthy physically active women aged between 18 to 30 years split equally into two groups according to BW: G1 (n = 14), BW between 2500 g and 3200 g and G2 (n = 14), BW > 3200 g. The groups remained seated at rest for 15 min, followed by aerobic exercise on a treadmill (five minutes at 50–55% of maximum HR and 25 min 60–65% of maximum HR) and then remained seated for 60 min during recovery from the exercise. Cardiorespiratory parameters and HR variability (HRV) [RMSSD, HF (ms2)] were assessed before and during recovery from exercise. In G1, HR was increased from 0 to 20 min after exercise whilst in G2 HR was higher from 0 to 7 min following exercise. In G1, short-term HRV was increased from 5 to 10 min after exercise but in G2 it recovered prior to 5 min following effort. In conclusion, healthy term-born women with low normal BW present slower HR autonomic recovery after exercise

Extra polarization states of cosmological gravitational waves in alternative theories of gravity

Cosmological Gravitational Waves (GWs) are usually associated with the transverse-traceless part of the metric perturbations in the context of the theory of cosmological perturbations. These modes are just the usual polarizations `+' and `x' which appear in the general relativity theory. However, in the majority of the alternative theories of gravity, GWs can present more than these two polarization states. In this context, the Newman-Penrose formalism is particularly suitable for evaluating the number of non-null GW modes. In the present work we intend to take into account these extra polarization states for cosmological GWs in alternative theories of gravity. As an application, we derive the dynamical equations for cosmological GWs for two specific theories, namely, a general scalar-tensor theory which presents four polarization states and a massive bimetric theory which is in the most general case with six polarization states for GWs. The mathematical tool presented here is quite general, so it can be used to study cosmological perturbations in all metric theories of gravity.Comment: 26 pages, 1 figure. Accepted for publication in Classical and Quantum Gravity

Desempenho de genótipos de mandioca em um Argissolo eutrófico na região sudoeste da Amazônia.

Objetivou-se com esse trabalho avaliar diferentes genótipos de mandioca quanto ao desempenho agronômico e industrial para a região sudoeste amazônica, em Rondônia

Uso do modelo CROPGRO-Drybean na determinação das melhores datas de semeadura da "seca" para a região de Viçosa, MG.

O presente trabalho teve como objetivo, aplicar o modelo CROPGRO-Drybean, calibrado e testado, para a determinação das melhores datas de semeadura da ?seca? de três cultivares de feijão (Pérola, Ouro Negro e Ouro Vermelho), em condições de sequeiro, cultivados na região de Viçosa, estado de Minas Gerais. Realizou-se a simulação da produtividade do feijoeiro com base em dados de 31 safras compreendidas entre o período de 1975 a 2006. As simulações foram baseadas em dados meteorológicos diários de temperaturas máxima e mínima do ar, precipitação pluvial e radiação solar global, características físicohídricas do solo e dados de manejo da cultura. Por meio das análises realizadas nas simulações, observou-se que quanto mais tardio o plantio, menor a produtividade do feijão ?da seca? simulado para as três cultivares

Características morfogênicas do capim-marandu sob lotação contínua.

O conhecimento da morfogênese das plantas é de importância fundamental para que se possa tomar decisões de manejo das pastagens. As características morfogênicas influenciam estruturais, que por sua vez podem modificar o comportamento dos animais em pastejo. O objetivo do trabalho foi avaliar as características morfogênicas do capimmarandu, submetido a intensidades de pastejo em lotação contínua