Transmission-expansion planning using the DC model and nonlinear-programming technique

The paper presents a constructive heuristic algorithm (CHA) for solving directly the long-term transmission-network-expansion-planning (LTTNEP) problem using the DC model. The LTTNEP is a very complex mixed-integer nonlinear-programming problem and presents a combinatorial growth in the search space. The CHA is used to find a solution for the LTTNEP problem of good quality. A sensitivity index is used in each step of the CHA to add circuits to the system. This sensitivity index is obtained by solving the relaxed problem of LTTNEP, i.e. considering the number of circuits to be added as a continuous variable. The relaxed problem is a large and complex nonlinear-programming problem and was solved through the interior-point method (IPM). Tests were performed using Garver's system, the modified IEEE 24-Bus system and the Southern Brazilian reduced system. The results presented show the good performance of IPM inside the CHA.

Habitat patch size modulates terrestrial mammal activity patterns in Amazonian forest fragments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Assessment of tropical forest degradation by selective logging and fire using Landsat imagery

Many studies have assessed the process of forest degradation in the Brazilian Amazon using remote sensing approaches to estimate the extent and impact by selective logging and forest fires on tropical rain forest. However, only a few have estimated the combined impacts of those anthropogenic activities. We conducted a detailed analysis of selective logging and forest fire impacts on natural forests in the southern Brazilian Amazon state of Mato Grosso, one of the key logging centers in the country. To achieve this goal a 13-year series of annual Landsat images (1992-2004) was used to test different remote sensing techniques for measuring the extent of selective logging and forest fires, and to estimate their impact and interaction with other land use types occurring in the study region. Forest canopy regeneration following these disturbances was also assessed. Field measurements and visual observations were conducted to validate remote sensing techniques. Our results indicated that the Modified Soil Adjusted Vegetation Index aerosol free (MSAVI(af)) is a reliable estimator of fractional coverage under both clear sky and under smoky conditions in this study region. During the period of analysis, selective logging was responsible for disturbing the largest proportion (31%) of natural forest in the study area, immediately followed by deforestation (29%). Altogether, forest disturbances by selective logging and forest fires affected approximately 40% of the study site area. Once disturbed by selective logging activities, forests became more susceptible to fire in the study site. However, our results showed that fires may also occur in undisturbed forests. This indicates that there are further factors that may increase forest fire susceptibility in the study area. Those factors need to be better understood. Although selective logging affected the largest amount of natural forest in the study period, 35% and 28% of the observed losses of forest canopy cover were due to forest fire and selective logging combined and to forest fire only, respectively. Moreover, forest areas degraded by selective logging and forest fire is an addition to outright deforestation estimates and has yet to be accounted for by land use and land cover change assessments in tropical regions. Assuming that this observed trend of land use and land cover conversion continues, we predict that there will be no undisturbed forests remaining by 2011 in this study site. Finally, we estimated that 70% of the total forest area disturbed by logging and fire had sufficiently recovered to become undetectable using satellite data in 2004. (C) 2010 Elsevier B.V. All rights reserved.

Evolutionary multi-move path-relinking for transmission network expansion planning

This paper presents the application of a new metaheuristic algorithm to solve the transmission expansion planning problem. A simple heuristic, using a relaxed network model associated with cost perturbation, is applied to generate a set of high quality initial solutions with different topologies. The population is evolved using a multi-move path-relinking with the objective of finding minimum investment cost for the transmission expansion planning problem employing the DC representation. The algorithm is tested on the southern Brazilian system, obtaining the optimal solution for the system with better performance than similar metaheuristics algorithms applied to the same problem. ©2010 IEEE.

Novas aplicações de metaheurísticas na solução do problema de planejamento da expansão do sistema de transmissão de energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aspectos da biologia larval de Chrysomya megacephala (F.) (Diptera : calliphoridae): curva de crescimento e período de mais rápido desenvolvimento larval

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Evolutionary trends in Iridaceae: new cytogenetic findings from the New World

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Correlates of blood pressure according to early, on time, and late maturation in adolescents

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Benthic foraminiferal assemblages of the South Brazil: Relationship to water masses and nutrient distributions

Using distributions of benthic Foraminifera and bottom-water variables (depth, salinity, temperature, oxygen, suspended matter, organic matter, phosphate, silicate, nitrite, and nitrate), we investigated movements of water masses on the South Brazilian Shelf (27-30 degrees S) and assessed the seasonality of continental runoff on the distribution of shelf water masses. The data were obtained from water and sediment samples collected in the austral winter of 2003 and austral summer of 2004 in three transects. The terrestrial nutrient input was significantly reduced at stations away from the coast, but high values of nutrients were maintained in subsurface waters due the presence of South Atlantic Central Water (SACW) at greater depths. At shallow sampling stations the influence of freshwater runoff was related to (1) the dominance of calcareous benthic Foraminifera, such as lagoon-related Pseudononion atlanticum, Hanzawaia boueana, Bulimina marginata, Bolivina striatula, Elphidium poeyanum, together with several agglutinated species, including Arenoparrella mexicana, Gaudryina exilis, and Trochammina spp., common in coastal environments subject to wide salinity fluctuations. In contrast, smaller forms and higher species diversity characterized the assemblage at offshore stations. In winter, the presence of Buccella peruviana and Uvigerina peregrina at Santa Marta Cape suggest the possible transport of those species of Subantarctic Shelf Waters (SASW) origin. Foraminifera associated to Subtropical Shelf Water (STSW) were dominated by Globocassidulina subglobosa in both seasons. In summer, the occurrence of U. peregrina in the shallower stations suggested the influence of SACW nutrients brought up by upwelling of deeper waters. (C) 2008 Elsevier Ltd. All rights reserved.

Lack of COI variation for Clavelina oblonga (Tunicata, Ascidiacea) in Brazil: Evidence for its human-mediated transportation?

Recent studies indicate that ascidians are efficiently dispersed by human transport. We have chosen the mitochondrial gene cytochrome c oxidase subunit I (COI) to address whether Clavelina oblonga is an introduced species in the Brazilian coast. Colonies of C. oblonga were sampled in different localities along Atlantic coasts of USA, Panama, and Brazil. The sequencing of 92 colonies resulted in three haplotypes for the species, two unique to Florida and the other shared by exemplars collected in Brazil and Panama; the latter haplotype is identical to the published sequence of Azores. Our evidence, including the absence of C. oblonga in the country's northern tropical waters, its association with artificial habitats and lack of COI variation suggest that the species has been introduced in the southeastern and southern Brazilian coasts. Previous records (85 years old) suggest that it could be a relatively long-term introduction.

Polimorphisms in Inflammasome Genes Are Involved in the Predisposition to Systemic Lupus Erythematosus

Recent findings provide evidence of inflammasome critical role in the predisposition to autoimmune disorders. The involvement of inflammasome in the pathogenesis of systemic lupus erythematosus (SLE) has been hypothesized even if no significant association within inflammasome genes mutations or polymorphisms and lupus has been reported yet. We analyzed 14 single nucleotide polymorphisms (SNPs) within 7 inflammasome genes (NLRP1, NLRP3, NLRC4, AIM2, CARD8, CASP1, IL1B) in 144 patients affected by systemic lupus erythematosus and in 158 healthy controls from Southern Brazilian (state of Sao Paulo) with the aim of disclosing the possible role of inflammasome genes in the susceptibility of SLE. Our results demonstrated that NLRP1 rs2670660 SNP and the NLRP1 rs12150220-rs2670660 A-G haplotype were associated with SLE in our study population, and in particular with the development of nephritis, rash and arthritis. These findings are concordant with previously reported association of NLRP1 with vitiligo and type-1 diabetes underlining once more the involvement of NALP1 inflammasome in the pathogenesis of autoimmune disorders.

Fatty acid content of POM, sediment, foraminifer and peracarid samples obtained during POLARSTERN cruise ANT-XXIV/2 (PS71)

In order to investigate the diversity of diet composition in macrobenthic peracarid crustaceans from the Antarctic shelf and deep sea, the fatty acid (FA) composition of different species belonging to the orders Isopoda, Amphipoda, Cumacea and Tanaidacea was analysed. Multivariate analyses of the FA composition confirmed general differences between the orders, but also distinct differences within these orders. To gain information on the origin of the FAs found, the potential food sources sediment, POM and foraminiferans were included in the study. Most of the analysed amphipod species displayed high 18:1(n-9)-18:1(n-7) ratios, widely used as an indicator for a carnivorous component in the diet. Cumaceans were characterised by increased phytoplankton FA markers such as 20:5(n-3) (up to 29% of total FAs), suggesting a diet based on phytodetritus. High values of the FA 20:4(n-6) were found in some munnopsid isopods (up to 21% of total FAs) and some tanaidacean species (up to 19% of total FAs). 20:4(n-6) also occurred in high proportions in some foraminiferan samples (up to 21% of total fatty acids), but not in sediment and POM, possibly indicating the ingestion of foraminiferans by some peracarid crustaceans.