The role of pressure anisotropy in the turbulent intracluster medium

In low-density plasma environments, such as the intracluster medium (ICM), the Larmour frequency is much larger than the ion-ion collision frequency. In such a case, the thermal pressure becomes anisotropic with respect to the magnetic field orientation and the evolution of the turbulent gas is more correctly described by a kinetic approach. A possible description of these collisionless scenarios is given by the so-called kinetic magnetohydrodynamic (KMHD) formalism, in which particles freely stream along the field lines, while moving with the field lines in the perpendicular direction. In this way a fluid-like behavior in the perpendicular plane is restored. In this work, we study fast growing magnetic fluctuations in the smallest scales which operate in the collisionless plasma that fills the ICM. In particular, we focus on the impact of a particular evolution of the pressure anisotropy and its implications for the turbulent dynamics of observables under the conditions prevailing in the ICM. We present results from numerical simulations and compare the results which those obtained using an MHD formalism.Comment: 7 pages, 14 figures, Journal of Physics: Conference Serie

Constraining the evolution of the CMB temperature with SZ measurements from Planck data

The CMB temperature-redshift relation, T_CMB(z)=T_0(1+z), is a key prediction of the standard cosmology, but is violated in many non standard models. Constraining possible deviations to this law is an effective way to test the LambdaCDM paradigm and to search for hints of new physics. We have determined T_CMB(z), with a precision up to 3%, for a subsample (104 clusters) of the Planck SZ cluster catalog, at redshift in the range 0.01-- 0.94, using measurements of the spectrum of the Sunyaev Zel'dovich effect obtained from Planck temperature maps at frequencies from 70 to 353 GHz. The method adopted to provide individual determinations of T_CMB(z) at cluster redshift relies on the use of SZ intensity change, Delta I_SZ(nu), at different frequencies, and on a Monte-Carlo Markov Chain approach. By applying this method to the sample of 104 clusters, we limit possible deviations of the form T_CMB(z)=T_0(1+z)^(1-beta) to be beta= 0.022 +/- 0.018, at 1 sigma uncertainty, consistent with the prediction of the standard model. Combining these measurements with previously published results we get beta=0.016+/-0.012.Comment: submitted to JCAP, 21 pages, 8 figure

On the Uq[sl(2)]{\cal{U}}_{q}[sl(2)] Temperley-Lieb reflection matrices

This work concerns the boundary integrability of the spin-s ${\cal{U}}_{q}[sl(2)]$ Temperley-Lieb model. A systematic computation method is used to constructed the solutions of the boundary Yang-Baxter equations. For $s$ half-integer, a general $2s(s+1)+3/2$ free parameter solution is presented. It turns that for $s$ integer, the general solution has $2s(s+1)+1$ free parameters. Moreover, some particular solutions are discussed.Comment: LaTex 17 page

Composição químico-bromatológica de resíduos agroindustriais da região de Porto Velho-Rondônia.

O estudo foi conduzido no Laboratório de Análise de Solos e Plantas da Embrapa Rondônia, em Porto Velho. Foram utilizados os seguintes resíduos da agroindústria, farinha de pupunha (Bactris gasipaes Kunth) e torta de cupuaçú (Theobroma grandiflorum, Willd. Exp Spreng). Os resíduos foram obtidos na agroindústria do projeto RECA (Reflorestamento Econômico Consorciado e Adensado) localizado no distrito de Nova Califórnia, município de Porto Velho-Rondônia. Os resultados das análises bromatológicas dos resíduos demonstraram que a farinha de pupunha continha (valores expressos em % da MS): 94,35 matéria seca-MS, 5,84 de proteína bruta-PB, 56,46 de fibra em detergente neutro-FDN, 9,17 de fibra em detergente ácido-FDA, 1,35 de matéria mineral-MM, 47,26 de hemicelulose-HMC e 93,60 de matéria orgânica-MO. Para a torta de cupuaçú os valores foram de: 93,52 de MS, 12,59 de PB, 54,73 de FDN, 43,47 de FDA, 4,36 de MM, 11,26 de HC e 89,15 de MO. De acordo com a composição uímico-bromatológica dos resíduos, os mesmos demonstram elevado potencial para serem utilizados na dieta de ruminantes. Contudo necessitam estudos com a utilização de animais para verificar o desempenho digestivo dos resíduos

Características morfogênicas e estruturais de Brachiaria brizantha cv. BRS Piatã submetida ao sombreamento.

Com objetivo de avaliar a resposta da Brachiaria brizantha cv. Piatã a níveis de sombreamento (0, 25 e 50%), conduziu-se um experimento na Embrapa Rondônia em Porto Velho-Brasil, em delineamento experimental inteiramente casualizado com 15 repetições

Características morfogênicas e estruturais de Brachiaria brizantha cv. Marandu submetida ao sombreamento.

Com objetivo de avaliar a resposta da Brachiaria brizantha cv. Marandu a níveis de sombreamento (0, 25 e 50%), conduziu-se um experimento na Embrapa Rondônia em Porto Velho-Brasil, em delineamento experimental inteiramente casualizado com 15 repetições

Características morfogênicas e estruturais de Brachiaria brizantha cv. Xaraés submetida ao sombreamento.

Com objetivo de avaliar a resposta da Brachiaria brizantha cv. Xaraés a níveis de sombreamento (0, 25 e 50%), conduziu-se um experimento na Embrapa Rondônia em Porto Velho-Brasil, em delineamento experimental inteiramente casualizado com 15 repetições

Características morfogênicas e estruturais de Brachiaria ruziziensis submetida ao sombreamento.

o objetivo desse trabalho foi determinar e avaliar as características morfogênicas e estruturais da B. ruziziensis submetida a diferentes níveis de sombreamento

Ising Spin Glass in a Transverse Magnetic Field

We study the three-dimensional quantum Ising spin glass in a transverse magnetic field following the evolution of the bond probability distribution under Renormalisation Group transformations. The phase diagram (critical temperature $T_c$ {\em vs} transverse field $\Gamma$) we obtain shows a finite slope near $T=0$, in contrast with the infinite slope for the pure case. Our results compare very well with the experimental data recently obtained for the dipolar Ising spin glass LiHo$_{0.167}$Y$_{0.833}$F$_4$, in a transverse field. This indicates that this system is more apropriately described by a model with short range interactions than by an equivalent Sherrington-Kirkpatrick model in a transverse field.Comment: 7 pages, RevTeX3, Nota Cientifica PUC-Rio 23/9