Technological advances and mechanistic basis for fungal biopulping

Biopulping fundamentals, technology and mechanisms are reviewed in this article. Mill evaluation of Eucalyptus grandis wood chips biotreated by Ceriporiopsis subvermispora on a 50-tonne pilot-plant demonstrated that equivalent energy savings can be obtained in lab- and mill-scale biopulping. Some drawbacks concerning limited improvements in pulp strength and contamination of the chip pile with opportunist fungi have been observed. The use of pre-cultured wood chips as inoculum seed for the biotreatment process minimized contamination problems related to the use of blended mycelium and corn-steep liquor in the inoculation step. Alkaline wash restored part of the brightness in biopulps and marketable brightness values were obtained by one-stage bleaching with 5% H2O2 when bio-TMP pulps were under evaluation. Considering the current scenario, the understanding of biopulping mechanisms has gained renewed attention because more resistant and competitive fungal species could be selected with basis on a function-directed screening project. A series of studies aimed to elucidate structural changes in lignin during wood biodegradation by C. subvermispora had indicated that lignin depolymerization occurs during initial stages of wood biotreatment. Aromatic hydroxyls did not increase with the split of aryl-ether linkages, suggesting that the ether-cleavage-products remain as quitione-type structures. On the other hand, cellulose is more resistant to the attack by C subvermispora. MnP-initiated lipid peroxidation reactions have been proposed to explain degradation of non-phenolic lignin substructures by C subvermispora, while the lack of cellobiohydrolases and the occurrence of systems able to suppress Fenton`s reaction in the cultures have explained non-efficient cellulose degradation by this biopulping fungus. (C) 2007 Elsevier Inc. All rights reserved.

Relationship between technological properties and slab surface roughness of siliceous dimension stones

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[06/52521-0]

Fiscal policy and reelection in Brazilian municipalities

This paper uses a new panel of more than 2,000 Brazilian municipalities over 13 years to analyze the influence of public expenditures on the probability of mayors` reelection. We examine Brazilian municipal elections from 1988 to 2000 using a logit fixed-effects model. The results suggest that mayors who spend more during their terms of office increase the probability of their own reelection or of a successor of the same political party. In particular, higher capital spending over the years preceding elections and current expenditures in election years are beneficial to Brazilian incumbent mayors.

Brazilian foreign policy: Old and new paths as regards institutional aspects, multilateralism and foreign policy towards the South

This paper emphasizes the important changes in Brazilian foreign policy after Luiz Inacio Lula da Silva took tip the power in 2002. The paper defends the idea that it is not possible to argue that there were deep changes in comparison to Cardoso's administration. However, evidence shows that new things are happening as regards the design of a more active and clear foreign action line which led to institutional changes and to more incisive multilateral paths. This results both from the political profile of the direct operators of foreign policy and the aims of lite presidential diplomacy, The hypothesis dealt with on this paper consists on the fact that Lula's administration has not fully broken with the old administration practices, however the aims of global and regional integration are being plotted more clearly and with a higher degree of activism. This becomes clear in three aspects of the Brazilian foreign policy: the institutional framework, the practice of multilateralism and the foreign policy towards the South, the three topics analyzed in this paper.