Multifractal Properties of Aperiodic Ising Model: role of geometric fluctuations

The role of the geometric fluctuations on the multifractal properties of the local magnetization of aperiodic ferromagnetic Ising models on hierachical lattices is investigated. The geometric fluctuations are introduced by generalized Fibonacci sequences. The local magnetization is evaluated via an exact recurrent procedure encompassing a real space renormalization group decimation. The symmetries of the local magnetization patterns induced by the aperiodic couplings is found to be strongly (weakly) different, with respect to the ones of the corresponding homogeneous systems, when the geometric fluctuations are relevant (irrelevant) to change the critical properties of the system. At the criticality, the measure defined by the local magnetization is found to exhibit a non-trivial F(alpha) spectra being shifted to higher values of alpha when relevant geometric fluctuations are considered. The critical exponents are found to be related with some special points of the F(alpha) function and agree with previous results obtained by the quite distinct transfer matrix approach.Comment: 10 pages, 7 figures, 3 Tables, 17 reference

Artrite encefalite caprina viral: um alerta aos produtores

O objetivo deste trabalho é informar e alertar os produtores dos principais indicadores clínicos, vias de transmissão, formas de diagnóstico, prevenção e controle da CAEbitstream/item/17592/1/Comunicado-Tecnico_2009.pd

Activity control in nitrifying biofilms: application of respirometric tests

Nitrification is the biological oxidation of ammonia to nitrate via nitrite. These reactions are performed by aerobic autotrophic microorganisms, commonly known as nitrifiers. The nitrifiers are generally constituted of ammonia oxidizing bacteria and nitrite oxidizing bacteria. They are very sensitive to environmental factors, namely the pH, which has its optimum value in the range of 7.5 to 8.5 (Sharma end Ahlert, 1977) A simple method, the respiration rate measurement, has been extensively used in literature to characterize microbial populations in suspended cultures (Kristensen et al., 1992, Nowak and Svardal, 1993) and to monitor the nitrification performance of immobilized nitrifiers (Nakamura et al., 1995) and nitrifying activated sludge processes (Surmacz-Gorska et al., 1996). Respiration refers to reactions that use oxygen as an electron acceptor. The aim of the present study is to characterize the functional microorganism groups of a nitrifying biofilm using a simple microbial activity measurement, the respiration rate, and to use this information to identify disturbances that have an impact on process performance

Gauge dependenceof the order parameter anomalous dimension in the Ginzburg-Landau model and the critical fluctuations in superconductors

The critical fluctuations of superconductors are discussed in a fixed dimension scaling suited to describe the type II regime. The gauge dependence of the anomalous dimension of the scalar field is stablished exactly from the Ward-Takahashi identities. Its fixed point value gives the $\eta$ critical exponent and it is shown that $\eta$ is gauge independent, as expected on physical grounds. In the scaling considered, $\eta$ is found to be zero at 1-loop order, while $\nu\approx 0.63$. This result is just the 1-loop values for the XY model obtained in the fixed dimension renormalization group approach. It is shown that this XY behavior holds at all orders. The result $\eta=\eta_{XY}$ should be contrasted with the negative values frequently reported in the literature.Comment: EuroLaTex, 7 pages, 2 figures, reference updated; version to be published in Europhysics Letter

Tratamento alternativo de águas residuais de banhos carrapaticidas de aspersão.

bitstream/CPPSE-2010/18926/1/PROCIBolPesDes21ARAN2009.00285.pdfISSN 1517-1