The Camamu Basin Offshore Environmental Monitoring through Remote Sensing

In this paper, multispectral remote sensing data from MODIS-Aqua were used to caracterize the Camamu offshore basin and to monitor 6 production wells located in the Manati field, eastern Brazil, showing their great potential for environmental monitoring for the oil drilling and gas industries. Results were based on the interpretation of SST, Chlorophyll-a and K490 derived from the Aqua satellite passes on march 4th and july 12th, as well as, monthly time series for each of these geophysical parameters. SST values show an opposite behaviour when compared to Chlorophyll-a and K490, with the last two parameters changing one order of magnitude seasonally

A COMPETITIVIDADE DO ARROZ GAÚCHO E SEUS CONDICIONANTES

This study aims to identify the main factors affecting rice supply in the state of Rio Grande do Sul and its competitiveness in Brazilian market. The Brazilian rice sector showed significant changes in the food chain after new agricultural policies, market liberalization and the Mercosul creation, which determined significant modifications in the allocation of production, in the quality of rice and in the productive structure of this sector.O presente estudo identifica os principais fatores que afetaram a produção de arroz no Estado do Rio Grande do Sul e a sua competitividade no mercado brasileiro. O setor arrozeiro brasileiro apresentou significativas mudanças na sua cadeia agroalimentar após o fim da política de incentivos e créditos subsidiados, a abertura comercial e a formação do Mercosul, que determinaram modificações substanciais na distribuição da produção no Brasil, na qualidade do produto e na estrutura produtiva do setor

Catalytic Thr or ser Residue Modulates Structural Switches in 2-Cys Peroxiredoxin by Distinct Mechanisms

Typical 2-Cys Peroxiredoxins (2-Cys Prxs) reduce hydroperoxides with extraordinary rates due to an active site composed of a catalytic triad, containing a peroxidatic cysteine (C P ), an Arg, and a Thr (or Ser). 2-Cys Prx are involved in processes such as cancer; neurodegeneration and host-pathogen interactions. During catalysis, 2-Cys Prxs switch between decamers and dimers. Analysis of 2-Cys Prx structures in the fully folded (but not locally unfolded) form revealed a highly conserved, non-conventional hydrogen bond (CH-π) between the catalytic triad Thr of a dimer with an aromatic residue of an adjacent dimer. In contrast, structures of 2-Cys Prxs with a Ser in place of the Thr do not display this CH-π bond. Chromatographic and structural data indicate that the Thr (but not Ser) destabilizes the decamer structure in the oxidized state probably through steric hindrance. As a general trend, mutations in a yeast 2-Cys Prx (Tsa1) favoring the dimeric state also displayed a decreased catalytic activity. Remarkably, yeast naturally contains Thr-Ser variants (Tsa1 and Tsa2, respectively) with distinct oligomeric stabilities in their disulfide states

Oxidative modification of proteins: from damage to catalysis, signaling, and beyond

Significance: The systematic investigation of oxidative modification of proteins by reactive oxygen species started in 1980. Later, it was shown that reactive nitrogen species could also modify proteins. Some protein oxidative modifications promote loss of protein function, cleavage or aggregation, and some result in proteo-toxicity and cellular homeostasis disruption. Recent Advances: Previously, protein oxidation was associated exclusively to damage. However, not all oxidative modifications are necessarily associated with damage, as with Met and Cys protein residue oxidation. In these cases, redox state changes can alter protein structure, catalytic function, and signaling processes in response to metabolic and/or environmental alterations. This review aims to integrate the present knowledge on redox modifications of proteins with their fate and role in redox signaling and human pathological conditions. Critical Issues: It is hypothesized that protein oxidation participates in the development and progression of many pathological conditions. However, no quantitative data have been correlated with specific oxidized proteins or the progression or severity of pathological conditions. Hence, the comprehension of the mechanisms underlying these modifications, their importance in human pathologies, and the fate of the modified proteins is of clinical relevance. Future Directions: We discuss new tools to cope with protein oxidation and suggest new approaches for integrating knowledge about protein oxidation and redox processes with human pathophysiological conditions