Актерское мастерство в китайском классическом театре

Des phénotypes enzymatiques (estérases et malate déshydrogénases) ont été utilisés pour la caractérisation de 90 populations de #Meloidogyne$originaires de différentes régions du Brésil. Nous avons employé une technique simplifiée pour les analyses de routine. Les protéines solubles sont séparées à partir d'une seule femelle par électrophorèse horizontale, en gel de 1 mm d'épaisseur à 7$, 39 #M. javanica, six #M. arenaria, deux #M. exigua, huit #M. hapla, deux #M. graminicola et neuf #Meloidogyne spp. Parmi les espèces atypiques, #Meloidogyne sp. 1 ressemble à #M. javanica par la configuration périnéale et peut être différenciée en électrophorèse par l'absence d'une bande estérasique et sa capacité à se développer sur le poivron. #Meloidogyne sp. 2, le plus virulent parasite du caféier dans l'état du Parana, correspond à une espèce non encore décrite. Les profils enzymatiques ne donnent malheureusement aucune information sur les races de #M. incognita et #M. arenaria$. (Résumé d'auteur

Symplectic evolution of Wigner functions in markovian open systems

The Wigner function is known to evolve classically under the exclusive action of a quadratic hamiltonian. If the system does interact with the environment through Lindblad operators that are linear functions of position and momentum, we show that the general evolution is the convolution of the classically evolving Wigner function with a phase space gaussian that broadens in time. We analyze the three generic cases of elliptic, hyperbolic and parabolic Hamiltonians. The Wigner function always becomes positive in a definite time, which is shortest in the hyperbolic case. We also derive an exact formula for the evolving linear entropy as the average of a narrowing gaussian taken over a probability distribution that depends only on the initial state. This leads to a long time asymptotic formula for the growth of linear entropy.Comment: this new version treats the dissipative cas

Fredholm methods for billiard eigenfunctions in the coherent state representation

We obtain a semiclassical expression for the projector onto eigenfunctions by means of the Fredholm theory. We express the projector in the coherent state basis, thus obtaining the semiclassical Husimi representation of the stadium eigenfunctions, which is written in terms of classical invariants: periodic points, their monodromy matrices and Maslov indices.Comment: 12 pages, 10 figures. Submitted to Phys. Rev. E. Comments or questions to [email protected]

Defensivos químicos no combate ao "ácaro rajado" Tetranychus urticae Koch, 1836, em algodão

A field test was carried out in Americana, State of São Paulo, Brazil, to evaluate the control of the "two spotted spider mite", the main pest on cotton in that area. The treatments were eitht with four repetitions (each repetition ocupied 150 m² and each treatment, 600 m²). The treatments and active ingredients per hectare were as follows: A) check; B) triazophos, 300 g; C) monocrotophos, 600 g; D) biphenthrin, 55 g; E) fenpropathrin, 150 g; F) biphenthrin, 60 g; G) binapacryl, 800 g; H) clofentezine, 750 g. Five counts of the mite were made: the first, three days before the spray and 01, 05, 08 and 13 days after spraying. The best results were obtained with biphenthrin and binapacryl (05 days); biphenthrin and clofentezine (08 days) and clofentezine (13 days).Com o objetivo de se conhecer a ação de vários produtos químicos contra o ácaro rajado, principal praga algodão em diversas áreas do Estado de São Paulo, foi instalado campo de experimentação em Americana. A aplicação foi feita em 17.02.1984, por meio de atomizador costal de 12 litros de capacidade, à razão de 200 litros de água por hectare. Tratamentos: oito, com quatro repetições, em delineamento experimental de blocos ao acaso. Cada parcela (canteiro) media 150 m² (portanto, 600 m² por tratamento). A- testemunha; B - triazofós, 300 g; C - monocrotofós, 600 g; D- bifentrina, 55 g; E - fempropatrina , 150 g; - bifentrina, 60 g; G - binapacril, 800 g; H- clofentezina, 750 g. As quantidades citadas acima são de ingre diente ativo por hectare. Os melhores foram a clofentezina e a bifentrina (Quadros II e III)

Efficiency of some chemical pesticides against the fall armyworm Spodoptera frugiperda (J. E. Smith, 1797) on corn field

The fall armyworm is one of the most important pest on corn fields. It causes enormous losses almost every year. In order to know the effects of some chemicals against the caterpillars, a study was conducted under field conditions in Piracicaba, State of São Paulo, Brazil, durin December of 1983. Plants were sprayed (200 liters per hectare) with a twenty liter costal manual sprayer. The treatments were nine: A - check (nothing was applied). B - moncrorophos, 240 g; C - biphenthrin 10 g; D - triazophos, 200 g; E - carbamate UC 75118, 150 g; F - monocrotophos, 400 g; G - acephate, 375 g; H - carbamate UC 76724:, 150 g; I - c lofentezine, 250 g. The quantities mentioned above are of active ingredient used per hectare. Two days after the spray, the best pesticides were triazophos and biphenthrin. After 07 days no one product had a good efficiency.A lagarta do cartucho do milho é um sério depredador da cultura do milho. Quase todos os anos, os danos ocasionados às plantas são grandes. Para se conhecer o efeito de alguns defensivos sobre a citada lagarta, realizou-se este trabalho experimental, instalado em Piracicaba, SP, a 09 de dezembro de l983. Os produtos foram aplicados com pulverizador costal, manual, de 20 litros de capacidade, provido de bico em leque Teejet 8002. Utilizaram-se 200 litros de água por hectare e 30 cm³ de "Extravon" (espalhante-adesivo) por 100 litros de calda. Os tratamentos foram nove: A - testemu nha; B - monocrotofós, 240 g; C - bifentrina, 10 g; D - triazofós, 200 g; E -carbamato UC 75118, 150 g; F - monocro tofós, 400 g; G - acefato, 375 g; H - cabamato UC 76724, 150 g; I - clofentezina, 250 g. As quantidades acima são de ingrediente ativo por hectare. Aos 02 dias da pulverização, os melhores foram o triazofós e a bifentrina. Aos 07 dias, nenhum produto apresentava boa eficiência

Schottky barrier heights at polar metal/semiconductor interfaces

Using a first-principle pseudopotential approach, we have investigated the Schottky barrier heights of abrupt Al/Ge, Al/GaAs, Al/AlAs, and Al/ZnSe (100) junctions, and their dependence on the semiconductor chemical composition and surface termination. A model based on linear-response theory is developed, which provides a simple, yet accurate description of the barrier-height variations with the chemical composition of the semiconductor. The larger barrier values found for the anion- than for the cation-terminated surfaces are explained in terms of the screened charge of the polar semiconductor surface and its image charge at the metal surface. Atomic scale computations show how the classical image charge concept, valid for charges placed at large distances from the metal, extends to distances shorter than the decay length of the metal-induced-gap states.Comment: REVTeX 4, 11 pages, 6 EPS figure

Universality of the Lyapunov regime for the Loschmidt echo

The Loschmidt echo (LE) is a magnitude that measures the sensitivity of quantum dynamics to perturbations in the Hamiltonian. For a certain regime of the parameters, the LE decays exponentially with a rate given by the Lyapunov exponent of the underlying classically chaotic system. We develop a semiclassical theory, supported by numerical results in a Lorentz gas model, which allows us to establish and characterize the universality of this Lyapunov regime. In particular, the universality is evidenced by the semiclassical limit of the Fermi wavelength going to zero, the behavior for times longer than Ehrenfest time, the insensitivity with respect to the form of the perturbation and the behavior of individual (non-averaged) initial conditions. Finally, by elaborating a semiclassical approximation to the Wigner function, we are able to distinguish between classical and quantum origin for the different terms of the LE. This approach renders an understanding for the persistence of the Lyapunov regime after the Ehrenfest time, as well as a reinterpretation of our results in terms of the quantum--classical transition.Comment: 33 pages, 17 figures, uses Revtex

Holographic dark energy in a non-flat universe with Granda-Oliveros cut-off

Motivated by Granda and Oliveros (GO) model, we generalize their work to the non-flat case. We obtain the evolution of the dark energy density, the deceleration and the equation of state parameters for the holographic dark energy model in a non-flat universe with GO cut-off. In the limiting case of a flat universe, i.e. $k = 0$, all results given in GO model are obtained.Comment: 11 pages, 5 figure

What is the Nature of EUV Waves? First STEREO 3D Observations and Comparison with Theoretical Models

One of the major discoveries of the Extreme ultraviolet Imaging Telescope (EIT) on SOHO were intensity enhancements propagating over a large fraction of the solar surface. The physical origin(s) of the so-called `EIT' waves is still strongly debated. They are considered to be either wave (primarily fast-mode MHD waves) or non-wave (pseudo-wave) interpretations. The difficulty in understanding the nature of EUV waves lies with the limitations of the EIT observations which have been used almost exclusively for their study. Their limitations are largely overcome by the SECCHI/EUVI observations on-board the STEREO mission. The EUVI telescopes provide high cadence, simultaneous multi-temperature coverage, and two well-separated viewpoints. We present here the first detailed analysis of an EUV wave observed by the EUVI disk imagers on December 07, 2007 when the STEREO spacecraft separation was $\approx 45^\circ$. Both a small flare and a CME were associated with the wave cadence, and single temperature and viewpoint coverage. These limitations are largely overcome by the SECCHI/EUVI observations on-board the STEREO mission. The EUVI telescopes provide high cadence, simultaneous multi-temperature coverage, and two well-separated viewpoints. Our findings give significant support for a fast-mode interpretation of EUV waves and indicate that they are probably triggered by the rapid expansion of the loops associated with the CME.Comment: Solar Physics, 2009, Special STEREO Issue, in pres