Pressure-induced hole doping of the Hg-based cuprate superconductors

We investigate the electronic structure and the hole content in the copper-oxygen planes of Hg based high Tc cuprates for one to four CuO2 layers and hydrostatic pressures up to 15 GPa. We find that with the pressure-induced additional number of holes of the order of 0.05e the density of states at the Fermi level changes approximately by a factor of 2. At the same time the saddle point is moved to the Fermi level accompanied by an enhanced k_z dispersion. This finding explains the pressure behavior of Tc and leads to the conclusion that the applicability of the van Hove scenario is restricted. By comparison with experiment, we estimate the coupling constant to be of the order of 1, ruling out the weak coupling limit.Comment: 4 pages, 4 figure

Ocorrência de Cryphonectria cubensis em árvores de Eucalyptus dunnii em Colombo, estado do Paraná.

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Tailored quantum dots for entangled photon pair creation

We compare the asymmetry-induced exchange splitting delta_1 of the bright-exciton ground-state doublet in self-assembled (In,Ga)As/GaAs quantum dots, determined by Faraday rotation, with its homogeneous linewidth gamma, obtained from the radiative decay in time-resolved photoluminescence. Post-growth thermal annealing of the dot structures leads to a considerable increase of the homogeneous linewidth, while a strong reduction of the exchange splitting is simultaneously observed. The annealing can be tailored such that delta_1 and gamma become comparable, whereupon the carriers are still well confined. This opens the possibility to observe polarization entangled photon pairs through the biexciton decay cascade.Comment: 4 pages, 4 figure

Pilot, Rollout and Monte Carlo Tree Search Methods for Job Shop Scheduling

Greedy heuristics may be attuned by looking ahead for each possible choice, in an approach called the rollout or Pilot method. These methods may be seen as meta-heuristics that can enhance (any) heuristic solution, by repetitively modifying a master solution: similarly to what is done in game tree search, better choices are identified using lookahead, based on solutions obtained by repeatedly using a greedy heuristic. This paper first illustrates how the Pilot method improves upon some simple well known dispatch heuristics for the job-shop scheduling problem. The Pilot method is then shown to be a special case of the more recent Monte Carlo Tree Search (MCTS) methods: Unlike the Pilot method, MCTS methods use random completion of partial solutions to identify promising branches of the tree. The Pilot method and a simple version of MCTS, using the $\varepsilon$-greedy exploration paradigms, are then compared within the same framework, consisting of 300 scheduling problems of varying sizes with fixed-budget of rollouts. Results demonstrate that MCTS reaches better or same results as the Pilot methods in this context.Comment: Learning and Intelligent OptimizatioN (LION'6) 7219 (2012

GEOS-5 Chemistry Transport Model User's Guide

The Goddard Earth Observing System version 5 (GEOS-5) General Circulation Model (GCM) makes use of the Earth System Modeling Framework (ESMF) to enable model configurations with many functions. One of the options of the GEOS-5 GCM is the GEOS-5 Chemistry Transport Model (GEOS-5 CTM), which is an offline simulation of chemistry and constituent transport driven by a specified meteorology and other model output fields. This document describes the basic components of the GEOS-5 CTM, and is a user's guide on to how to obtain and run simulations on the NCCS Discover platform. In addition, we provide information on how to change the model configuration input files to meet users' needs

Resistência natural das espécies Eucalyptus cloeziana, Eucalyptus mycrocoris, Eucalyptus umbra, Corymbia citriodora e Corymbia maculata à degradação provocada pelo fungo Agrocybe perfecta, causador da podridão branca na madeira, in vitro.

Estudos práticos para a avaliação da resistência natural da madeira de eucalipto, têm recebido considerável atenção dos pesquisadores, em virtude das orientações que fornecem sobre o uso final do produto, evitando perdas econômicas. O apodrecimento da madeira pode ser causado por fungos decompositores. Alguns apresentam alta capacidade de degradação da lignina, cuja degradação é denominada podridão-branca. O objetivo deste trabalho foi analisar, em laboratório, a resistência natural da madeira de cinco espécies de eucalipto, a degradação provocada pelo fungo Agrocybe perfecta na madeira em diferentes posições ao longo do fuste.EBRAMEM