952 resultados para Sorting Nexin


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Energy policies and technological progress in the development of wind turbines have made wind power the fastest growing renewable power source worldwide. The inherent variability of this resource requires special attention when analyzing the impacts of high penetration on the distribution network. A time-series steady-state analysis is proposed that assesses technical issues such as energy export, losses, and short-circuit levels. A multiobjective programming approach based on the nondominated sorting genetic algorithm (NSGA) is applied in order to find configurations that maximize the integration of distributed wind power generation (DWPG) while satisfying voltage and thermal limits. The approach has been applied to a medium voltage distribution network considering hourly demand and wind profiles for part of the U.K. The Pareto optimal solutions obtained highlight the drawbacks of using a single demand and generation scenario, and indicate the importance of appropriate substation voltage settings for maximizing the connection of MPG.

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The distribution of petroleum products through pipeline networks is an important problem that arises in production planning of refineries. It consists in determining what will be done in each production stage given a time horizon, concerning the distribution of products from source nodes to demand nodes, passing through intermediate nodes. Constraints concerning storage limits, delivering time, sources availability, limits on sending or receiving, among others, have to be satisfied. This problem can be viewed as a biobjective problem that aims at minimizing the time needed to for transporting the set of packages through the network and the successive transmission of different products in the same pipe is called fragmentation. This work are developed three algorithms that are applied to this problem: the first algorithm is discrete and is based on Particle Swarm Optimization (PSO), with local search procedures and path-relinking proposed as velocity operators, the second and the third algorithms deal of two versions based on the Non-dominated Sorting Genetic Algorithm II (NSGA-II). The proposed algorithms are compared to other approaches for the same problem, in terms of the solution quality and computational time spent, so that the efficiency of the developed methods can be evaluated

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Understanding the historical and ecological relationships which are influent in current biological diversity is one of the most challenging tasks of evolutionary biology. Recent systematics emphasizes the need of integrative approaches to delimit different lineages and species. The northeastern Brazil, mostly placed in Caatinga biome, is characterized by a semi-arid weather, low precipitation and seasonal behavior of rivers. This region is regarded lacking as ichthyological knowledge and one of the most threatened by anthropic activities. Further, will be affected by a massive water diverpsion work that will transfer waters from São Francisco basin, to other major four basins: Jaguaribe, Apodi-Mossoró, Piranhas-Açu and Paraiba do Norte. Loss of diversity and richness, hibridizitation, community interactions changes, population homogenization, changes in water quality and flow regime, are examples of environmental impacts already related with similar works. The present study aims to investigate morphological and molecular variation of Cichlasoma orientale Kullander 1983 and Crenicichla menezesi Ploeg 1991, two cichlid species present in northeastern Brazil basins. Further, the study aims to evaluate the influence of geomorphological and climatic processes in this variation, and point some possible impacts of the artificial connectivity which can be brought by São Francisco interbasin water transfer to their population dynamics. Geometric morphometrics and phylogeographical analysis were used to investigate the populations from three different hydrological regions. Our results showed a significant morphological variation of populations from basins that are involved in the São Franscisco s diversion project, not related to an ancient separation between populations, emphasizing morphological variation which could represent a set of plastic responses to the variable hydrological regime in Northeastern Brazil. The role of plastical responses in naturally variable habitats as well as the potential disturbs that could be brought by the interbasin water transfer works are discussed here. Further, our molecular data allowed us to make inferences about species distribution and their taxonomy, and identification of a potential new species of Crenicichla for São Francisco river basin. Our data also allowed to identify some shared haplotypes for both species, which could be related to lineage sorting scenarios or recent gene flow between populations. However a strong structure in most of the pairwise comparisons between populations for both species was revealed. Climatic events such as Atlantic forest regression during the Pleistocene, sea level fluctuations and dispersion by paleorivers in the mouth of Apodi-Mossoró river, and neotectonic events regulating the connection between drainages are likely to have had a contribution for the actual lineages distribution in northeastern Brazil. Further, analysis of molecular variation (AMOVA and SAMOVA) showed that the actual basin s isolation is an important factor to molecular variation, in spite of the signal of recent contact between some basins. Different genetic diversity patterns between species could be related to multiple historic events of colonization, basins landscapes or biological differences. The present study represents the first effort of integrative systematics involving fish species of northeastern Brazil, and showed important morphological and molecular patterns which could be irrecoverably affected by the artificial connection that might be caused by the São Francisco interbasin water transfer

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This dissertation deals with the characterization, distribution and provenience of heavy minerals along the Piranhas-Açu River, from the City of Parelhas (Seridó River) to your mouth at the City of Macau-RN. Many heavy minerals species were recorded in this study: clinoamphibole, epidote (including zoisite), garnet, sillimanite, tourmaline, staurolite, andalusite, zircon, rutile, augite, ilmenite, hematite and magnetite. Major transparent minerals, those forming more than 5% of some assemblages, are hornblende, epidote, tourmaline, staurolite and zircon. Predominant opaque mineral is ilmenite. Six assemblages were identified along the river: (i) Garnet-hornblende-tourmaline with sillimanite, when cutting rocks of the Seridó Formation; (ii) Hornblende-garnet-zircon, when crossing rocks of the Caicó gnaisse-migmatitic Complex; (iii) Hornblende-zircon-epidote-staurolite, when draining rocks of the Jucurutu Formation; (iv) Hornblende-zircon-epidote, when cutting rocks of the Açu Formation; (v) Hornblende-zircon-staurolite, on the lowermost Açu River, when crossing limestones of the Jandaíra Formation and (vi) Zircon-tourmaline-staurolite in the Açu River mouth (Cenozoic rocks) where coastal process dominate. Mineral ratios that reflect differences in grain shape, density, and selective chemical decomposition were used in an attempt to isolate the effects of source and process as controls of mineral variability. Reworking of the sediments was regionally effective in selective sorting; the more equant minerals (e.g. epidote) and heavier minerals (e.g. opaques) had a higher probability of being selected for permanent deposition during reworking. The processes of selective decomposition stand out at the river mouth. A priori knowledge of provenance, associated with the assemblage distribution and effects of process were utilized to the interpretations, that points to the follow provenances: hornblende comes from micashists of the Seridó Formation, orthognaisses and amphibolites of the Caico Complex, paragnaisses and paranphibolites of the Jucurutu Formation and granites intrusions; epidote comes from paragnaisses and calciosilicatics of the Jucurutu Formation, granites intrusions (-Npy3al/ca and -Npy3mz, gravels deposits and Açu Formation; Andalusite and staurolite come from the Seridó Formation; Sillimanite, tourmaline and garnet come from micashists of the Seridó Formation, as well as from quartzites of the Equador Formation; Zircon comes from Precambrian rocks (pink and prismatic zircon) and from sediments of several cycles (round zircon); Opaques come from all rocks cutted for the Piranhas-Açu River; Rutile comes from metamorphic rocks, in general; Augite comes from the Ceará-Mirim, Serra do Cuó and Macau volcanisms. The texture of gravels deposits reveals a sediment transport mechanisms by traction-current processes, together with a diagenetic clay matrix suggests a hot-humid environments for deposition. The presence of unstable heavy minerals assemblages, as well as pebbles of different composition and degrees of rounding and esfericity, indicate more than one source. The occurrence of calcio/alkaline granites suites, in areas closed to the gravel deposits, suggests that these intrusions are the main source of sediments. This could explain for instance, the significant amounts of epidote and presence of unstable heavy minerals (e.g. hornblende). The analyses of heavy minerals also show significante variability between the modern (Piranhas-Açu) and ancestral (Açu Formation) river sediments. In general, these variations reflect relatively higher unstable and lower stable heavy minerals contents of the modern Piranhas-Açu sediments. The absence of significant compositional differences probably reflects uniform weathering conditions

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Background: The first distinct differentiation event in mammals occurs at the blastocyst stage when totipotent blastomeres differentiate into either pluripotent inner cell mass (ICM) or multipotent trophectoderm (TE). Here we determined, for the first time, global gene expression patterns in the ICM and TE isolated from bovine blastocysts. The ICM and TE were isolated from blastocysts harvested at day 8 after insemination by magnetic activated cell sorting, and cDNA sequenced using the SOLiD 4.0 system.Results: A total of 870 genes were differentially expressed between ICM and TE. Several genes characteristic of ICM (for example, NANOG, SOX2, and STAT3) and TE (ELF5, GATA3, and KRT18) in mouse and human showed similar patterns in bovine. Other genes, however, showed differences in expression between ICM and TE that deviates from the expected based on mouse and human.Conclusion: Analysis of gene expression indicated that differentiation of blastomeres of the morula-stage embryo into the ICM and TE of the blastocyst is accompanied by differences between the two cell lineages in expression of genes controlling metabolic processes, endocytosis, hatching from the zona pellucida, paracrine and endocrine signaling with the mother, and genes supporting the changes in cellular architecture, stemness, and hematopoiesis necessary for development of the trophoblast.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The aim of the present study was to examine the benthic fauna in a marginal pond lateral to the Paranapanema River and to identify the main controlling factors of its distribution. Considering the small size of the lacustrine ecosystem, we expected that seasonal variations of the benthic community attributes are more important than spatial variations; Methods: Two samplings, one in March and another in August, were carried out at nine sites in the pond. Sediment samples were obtained through a Van Veen grab for invertebrate sorting, granulometric analysis, and for quantification of organic matter in sediment. Other abiotic factors were measured, such as water transparency, dissolved oxygen, pH, electric conductivity, temperature, and depth of sediment sampling sites. Regarding the comparative analysis at spatial scale, no significant variations in density of the benthic invertebrate community were found. Results: In relation to the studied abiotic factors, only depth presented significant differences among sampling sites; All the measured environmental parameters presented significant differences among sampling months, except depth and the physical and chemical characteristics of the sediment. The abundance of Chaoboridae and Chironomidae was the unique attribute with a significant difference in comparing the two months. A higher abundance of taxa occurred in August, especially for Oligochaeta, Nematoda, Chaoboridae, and Chironomidae; Conclusions: Because of the low structural complexity of the studied pond, we concluded that the changes in benthic macroinvertebrate community attributes were mainly due to seasonal effects.

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The deposits of the Permian Teresina Formation are mainly characterized by fi ne-grained siliciclastic rocks and centimetric intercalations of tempestites (bioclastic sandstones and coquinas). Despite the relevance of the bivalve-rich carbonate beds of the Teresina Formation to paleoenvironmental studies, their taphonomy is still poorly studied. The fossil concentration studied in this work was found in a quarry in the city of Irati, Rio Preto district, Parana State. The fossil concentration is located in the middle/upper portion of the unit, far from the top. The studied bed is a bioclastic, intraclastic, peloidal, grainstone/ packstone, with abundant bivalve shell fragments, pelitic and micritic intraclasts, peloids, rare ooids and oncoids, as well as permineralized of Lycophyta microphylles and fish scales. The grains of this carbonate concentration show: high degree of time-averaging, variable degree of packing (dense to disperse), no sorting and chaotic orientation. Notably, the concentration includes a mixture of elements which are indicative of: a) restrictive, low energy, carbonate environment (peloids, ooids and oncoids); b) subaerial environment surrounding the main body of water (Lycophyta microphylles) and c) quiet-water environment punctuated by storm events, where the suspension-feeding bivalves thrived. At least four depositional events caused by storm fl ows were recorded. The amalgamated nature of the bed is a result of storm events in an intracratonic basin with very low seafl oor slope and low rates of sedimentation and subsidence.

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This paper introduces an improved tabu-based vector optimal algorithm for multiobjective optimal designs of electromagnetic devices. The improvements include a division of the entire search process, a new method for fitness assignment, a novel scheme for the generation and selection of neighborhood solutions, and so forth. Numerical results on a mathematical function and an engineering multiobjective design problem demonstrate that the proposed method can produce virtually the exact Pareto front, in both parameter and objective spaces, even though the iteration number used by it is only about 70% of that required by its ancestor.

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The widespread falsification and/or adulteration of commercially available pharmaceutical preparations call for reliable methods of drug identification, preferably through selective and rapid sorting color tests that could be undertaken with minimum equipment remote from laboratory facilities. The present work deals with a convenient adaptation and refinement of a spot test devised by Feigl (1966) for urotropine, based on the hydrolytic cleavage of that substance in the presence of sulfuric acid, splitting out formaldehyde which is identified by its color reaction with chromotropic acid. A simple emergency kit was developed for the quick, efficient, inexpensive and easy performance of urotropine tests by semiskilled personnel even in the drugstore laboratory (or office) as well as in a mobile screening operation. It is shown that when the reagents are added according to the recommended sequence a self-heating system is generated, increasing substantially the reactions' rates and the test sensitivity as well. The identification limit found was 25 mug of urotropine, for both solid and liquid samples. The possible interference of 84 substances/materials was investigated. Interference was noted only for methylene blue, acriflavine, Ponceau Red, Bordeaux Red (these dyes are often included in urotropine dosage forms), pyramidone, dipyrone, quinine and tetracycline. A simple procedure for removing most of the interferences is described. Data for 8 commercial dosage forms and results obtained from their analysis are presented.