Interpolation of bilinear operators and compactness

The behavior of bilinear operators acting on interpolation of Banach spaces for the $\rho$ method in relation to the compactness is analyzed. Similar results of Lions-Peetre, Hayakawa and Person's compactness theorems are obtained for the bilinear case and the $\rho$ method.Comment: This work was published at "Nonlinear Analysis: Theory, Methods and Applications, Volume 73, Issue 2, 2010, Pages 526-537". Since there are some gaps in the original proof of Theorem 4.3, Here we give a new proof. For this, we change the Lemma 4.

Oxygen clamps in gold nanowires

We investigate how the insertion of an oxygen atom in an atomically thin gold nanowire can affect its rupture. We find, using ab initio total energy density functional theory calculations, that O atoms when inserted in gold nanowires form not only stable but also very strong bonds, in such a way that they can extract atoms from a stable tip, serving in this way as a clamp that could be used to pull a string of gold atoms.Comment: 4 pages; 4 figure

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Eficiência do estimulo hormonal e bioestimulação na taxa de ovulação, indução e sincronização do estro em caprinos.

A bioestimulação como coordenador de comportamento sexual. Bioestimulação da puberdade em fêmeas e machos. Efeito bioestimulador de liberação do hormonio luteinico

The Effect of Adverse Oil Price Shocks on Monetary Policy and Output Using a Dynamic Small Open Economy General Equilibrium Model With Staggered Price for Brazil

The aim of the present research is to use a model economy built for Brazil, based on an optimizing dynamic general equilibrium model, in order to perform numerical simulations to derive the ability of the artificial economy to explain the impact of monetary policy interventions on Brazilian short run economic performance in terms of the inflation rate, output gap, interest rate and level of economic activity in the face of an adverse oil shock. It is an extension of Bugarin et al. (2005) concentrating on the consequence of energy price increases, facing different monetary policy rules. Following Hall (1988 e 1990) and Finn (2000) it is considered that an increase in energy prices acts like a negative productivity shock. The model provides an accessible description of an artificial economy with a tractable micro-founded dynamic setting with forward looking rational agents in a small open economy with a staggered pricing mechanism that generates inflation inertia and recessionary disinflations. Alternative specification of monetary reaction functions are introduced into the model economy in order to perform a sensitivity analysis of derived impulse responses to those interventions facing the negative productivity shock. The preliminary results suggest that the introduction of habit persistence into the consumption hypothesis does not make much difference. However the introduction of different monetary reaction functions does alter the impulse response of output, inflation rate, and nominal interest rate. A common result is the decline in potential output for all models. Additionally, the only case where a reduction in the output gap is observed is when using the Taylor rule that takes into consideration the output gap and past interest rates with high persistence.

Disorder and the effective Mn-Mn exchange interaction in Ga1−x_{1-x}Mnx_xAs diluted magnetic semiconductors

We perform a theoretical study, using {\it ab initio} total energy density-functional calculations, of the effects of disorder on the $Mn-Mn$ exchange interactions for $Ga_{1-x}Mn_xAs$ diluted semiconductors. For a 128 atoms supercell, we consider a variety of configurations with 2, 3 and 4 Mn atoms, which correspond to concentrations of 3.1%, 4.7%, and 6.3%, respectively. In this way, the disorder is intrinsically considered in the calculations. Using a Heisenberg Hamiltonian to map the magnetic excitations, and {\it ab initio} total energy calculations, we obtain the effective \JMn, from first ($n=1$) all the way up to sixth ($n=6$) neighbors. Calculated results show a clear dependence in the magnitudes of the \JMn with the Mn concentration $x$. Also, configurational disorder and/or clustering effects lead to large dispersions in the Mn-Mn exchange interactions, in the case of fixed Mn concentration. Moreover, theoretical results for the ground-state total energies for several configurations indicate the importance of a proper consideration of disorder in treating temperature and annealing effects