A Population of Teraelectronvolt Pulsar Wind Nebulae in the H.E.S.S. Galactic Plane Survey

The most numerous source class that emerged from the H.E.S.S. Galactic Plane Survey are Pulsar Wind Nebulae (PWNe). The 2013 reanalysis of this survey, undertaken after almost 10 years of observations, provides us with the most sensitive and most complete census of gamma-ray PWNe to date. In addition to a uniform analysis of spectral and morphological parameters, for the first time also flux upper limits for energetic young pulsars were extracted from the data. We present a discussion of the correlation between energetic pulsars and TeV objects, and their respective properties. We will put the results in context with the current theoretical understanding of PWNe and evaluate the plausibility of previously non-established PWN candidates.Comment: 4 pages, 5 figures. In Proceedings of the 33rd International Cosmic Ray Conference (ICRC2013), Rio de Janeiro (Brazil

Lithostratigraphy, biostratigraphy, and stable-isotope stratigraphy of cores from ODP Leg 105 site surveys, Labrador Sea and Baffin Bay

Trigger weight (TWC) and piston (PC) cores obtained from surveys of the three sites drilled during Ocean Drilling Program (ODP) Leg 105 were studied in detail for benthic foraminiferal assemblages, total carbonate (all sites), planktonic foraminiferal abundances (Sites 645 and 647), and stable isotopes (Sites 646 and 647). These high-resolution data provide the link between modern environmental conditions represented by the sediment in the TWC and the uppermost cores of the ODP holes. This link provides essential control data for interpretating late Pleistocene paleoceanographic records from these core holes. At Site 645 in Baffin Bay, local correlation is difficult because the area is dominated by ice-rafted deposits and by debris flows and/or turbidite sedimentation. At the two Labrador Sea sites (646 and 647), the survey cores and uppermost ODP cores can be correlated. High-resolution data from the site survey cores also provide biostratigraphic data that refine the interpretations compiled from core-catcher samples at each ODP site

Tibouchina sellowiana (Cham.) Cogn.: enraizamento, anatomia e análises bioquímicas nas quatro estações do ano.

O presente trabalho buscou verificar os efeitos da aplicação de diferentes concentrações do ácido indolbutírico (AIB), em talco e em solução, no enraizamento de estacas caulinares de Tibouchina sellowiana (Cham.) Cogn. coletadas nas quatro estações do ano, bem como suas variações anatômicas e bioquímicas. Estacas semilenhosas foram tratadas com 0, 1500 e 3000 mg L-1 de ácido indolbutírico (AIB), em talco e solução 50% alcoólica. Após 65 dias em casa-de-vegetação, foram avaliados a porcentagem de estacas enraizadas, o número e o comprimento das raízes, a porcentagem de estacas com calos e a sobrevivência. O uso do AIB mostrou-se eficiente na indução radicial, sendo indiferente a forma em que foi aplicado. As estações mais promissoras foram a primavera (78,75%) com 3.000 mg L-1 ou mg kg-1 de AIB e o verão (63,12%) com 1.500 mg L-1 ou mg kg-1 de AIB. Das secções feitas na base das estacas, no momento da estaquia, não foi detectada nenhuma possível barreira anatômica ou diferença estrutural que promovesse variações no enraizamento. Análises bioquímicas feitas das estacas revelaram que as maiores concentrações de açúcares totais foram obtidas no inverno (83,21 mg g-1 de tecido) e no outono (72,79 mg g-1), as estações que também apresentaram as maiores concentrações de proteínas (4,69 e 3,95 mg g-1 respectivamente)

Slow dynamics in critical ferromagnetic vector models relaxing from a magnetized initial state

Within the universality class of ferromagnetic vector models with O(n) symmetry and purely dissipative dynamics, we study the non-equilibrium critical relaxation from a magnetized initial state. Transverse correlation and response functions are exactly computed for Gaussian fluctuations and in the limit of infinite number n of components of the order parameter. We find that the fluctuation-dissipation ratios (FDRs) for longitudinal and transverse modes differ already at the Gaussian level. In these two exactly solvable cases we completely describe the crossover from the short-time to the long-time behavior, corresponding to a disordered and a magnetized initial condition, respectively. The effects of non-Gaussian fluctuations on longitudinal and transverse quantities are calculated in the first order in the epsilon-expansion and reliable three-dimensional estimates of the two FDRs are obtained.Comment: 41 pages, 9 figure

Rotation Symmetry Spontaneous Breaking of Edge States in Zigzag Carbon Nanotubes

Analytical solutions of the edge states were obtained for the (N, 0) type carbon nanotubes with distorted ending bonds. It was found that the edge states are mixed via the distortion. The total energies for N=5 and N>=7 are lower in the asymmetric configurations of ending bonds than those having axial rotation symmetry. Thereby the symmetry is breaking spontaneously. The results imply that the symmetry of electronic states at the apex depends on the occupation; the electron density pattern at the apex could change dramatically and could be controlled by applying an external field.Comment: 19 pages, 3 figure

Dynamical field theory for glass-forming liquids, self-consistent resummations and time-reversal symmetry

We analyse the symmetries and the self-consistent perturbative approaches of dynamical field theories for glassforming liquids. In particular, we focus on the time-reversal symmetry (TRS), which is crucial to obtain fluctuation-dissipation relations (FDRs). Previous field theoretical treatment violated this symmetry, whereas others pointed out that constructing symmetry preserving perturbation theories is a crucial and open issue. In this work we solve this problem and then apply our results to the mode-coupling theory of the glass transition (MCT). We show that in the context of dynamical field theories for glass-forming liquids TRS is expressed as a nonlinear field transformation that leaves the action invariant. Because of this nonlinearity, standard perturbation theories generically do not preserve TRS and in particular FDRs. We show how one can cure this problem and set up symmetry-preserving perturbation theories by introducing some auxiliary fields. As an outcome we obtain Schwinger-Dyson dynamical equations that automatically preserve FDRs and that serve as a basis for carrying out symmetry-preserving approximations. We apply our results to MCT, revisiting previous field theory derivations of MCT equations and showing that they generically violate FDR. We obtain symmetry-preserving mode-coupling equations and discuss their advantages and drawbacks. Furthermore, we show, contrary to previous works, that the structure of the dynamic equations is such that the ideal glass transition is not cut off at any finite order of perturbation theory, even in the presence of coupling between current and density. The opposite results found in previous field theoretical works, such as the ones based on nonlinear fluctuating hydrodynamics, were only due to an incorrect treatment of TRS.Comment: 54 pages, 21 figure

Protocolos de Micropropagação de Plantas. I-Batata.

bitstream/item/44084/1/documento-317.pd

Micropropagação de batata 'BRS Ana': produção de material básico com alta sanidade.

bitstream/item/60642/1/CIRCULAR-118.pd