314 resultados para renovation


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The problems of combinatory optimization have involved a large number of researchers in search of approximative solutions for them, since it is generally accepted that they are unsolvable in polynomial time. Initially, these solutions were focused on heuristics. Currently, metaheuristics are used more for this task, especially those based on evolutionary algorithms. The two main contributions of this work are: the creation of what is called an -Operon- heuristic, for the construction of the information chains necessary for the implementation of transgenetic (evolutionary) algorithms, mainly using statistical methodology - the Cluster Analysis and the Principal Component Analysis; and the utilization of statistical analyses that are adequate for the evaluation of the performance of the algorithms that are developed to solve these problems. The aim of the Operon is to construct good quality dynamic information chains to promote an -intelligent- search in the space of solutions. The Traveling Salesman Problem (TSP) is intended for applications based on a transgenetic algorithmic known as ProtoG. A strategy is also proposed for the renovation of part of the chromosome population indicated by adopting a minimum limit in the coefficient of variation of the adequation function of the individuals, with calculations based on the population. Statistical methodology is used for the evaluation of the performance of four algorithms, as follows: the proposed ProtoG, two memetic algorithms and a Simulated Annealing algorithm. Three performance analyses of these algorithms are proposed. The first is accomplished through the Logistic Regression, based on the probability of finding an optimal solution for a TSP instance by the algorithm being tested. The second is accomplished through Survival Analysis, based on a probability of the time observed for its execution until an optimal solution is achieved. The third is accomplished by means of a non-parametric Analysis of Variance, considering the Percent Error of the Solution (PES) obtained by the percentage in which the solution found exceeds the best solution available in the literature. Six experiments have been conducted applied to sixty-one instances of Euclidean TSP with sizes of up to 1,655 cities. The first two experiments deal with the adjustments of four parameters used in the ProtoG algorithm in an attempt to improve its performance. The last four have been undertaken to evaluate the performance of the ProtoG in comparison to the three algorithms adopted. For these sixty-one instances, it has been concluded on the grounds of statistical tests that there is evidence that the ProtoG performs better than these three algorithms in fifty instances. In addition, for the thirty-six instances considered in the last three trials in which the performance of the algorithms was evaluated through PES, it was observed that the PES average obtained with the ProtoG was less than 1% in almost half of these instances, having reached the greatest average for one instance of 1,173 cities, with an PES average equal to 3.52%. Therefore, the ProtoG can be considered a competitive algorithm for solving the TSP, since it is not rare in the literature find PESs averages greater than 10% to be reported for instances of this size.

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Considerando-se que os critérios fotointerpretativos têm muito de subjetivo, com resultados que variam segundo o fotointérprete, pretendeu-se neste trabalho, ressaltar a utilização da densitometria como auxiliar na fotointerpretação da vegetação. No estudo foram utilizadas fotografias aéreas coloridas (transparências 23 x 23 cm) na escala 1:6.000. O filme colorido utilizado foi o Kodak Ektachrome MS Aerographic Film 2448. Desde que as fotografias estavam numa escala grande, foi bastante fácil identificar as culturas existentes na área bem como a vegetação natural. Cada categoria de vegetação foi classificada pela notação de Munsell. A densidade ótica foi medida por intermédio de um microdensitômetro de transmissão, marca Weston, modelo 877. Para cada item identificado nas fotografias foram feitas leituras de densidade ótica, para posterior comparação. Os dados obtidos foram utilizados para avaliar a importância das leituras densitométricas nas transparências coloridas, obtendo-se as seguintes conclusões principais: a) as medidas densitométricas ofereceram resultados mais consistentes que os obtidos por fotointerpretação convencional; b) a utilização do filme infravermelho colorido sugere a possibilidade de ampliar a resposta das leituras densitométricas.

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This work brings some reading about a few Norte-rio-grandenses writers collaborations published in literary papers which circulated during the third decade of the twentieth century in Brazil, in a way of enlarging the understanding of how the cultural debate was carried out in the years of the definition of the Brazilian Modernism, based on the relationships between literature and culture. Under the genres of prose and poetry, the selected textual collaborations for analysis have brought the traces of a small group of articulated authors in the Brazilian cultural scenery from the 1920 s, concerning the issues of the modern (linked to the modernist renovation) and the regional (under the aspects of the tradition). The set of the analyzed collaborations is representative of a modern-regional cultural practice marked by a tendency either local or cosmopolitan, thus, sharing a large dimension of the formation of the modern literary tradition, marked by different kinds of practices which give form to the project of a collective national awareness. The characterization of the existence of an intellectual field with big links, however with its own characteristics and a certain autonomy, which also gets integrated to the cultural debate of the so-called modernist years through the literary vehicles, gives to these intellectual people a co-participation in the renewing movement in the formation context of the brazilian cultural modernity of the early twentieth century

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The real estate dynamic originates new spatial forms, which can determine new uses and new places. We tried to analyze this work, the spatial transformations in the Ribeira district, Natal / RN, due to the advancement of the housing market that is gradually transforming the landscape with the introduction of new types of housing, especially by verticalization. The verticalization of the neighborhood occurs almost at once, changing the local landscape. Notwithstanding this process, given the rapid growth of Natal in the last two decades and the strategic location of the neighborhood, it is pertinent to note that, if not the process of vertical integration, perhaps the neighborhood had been at the mercy of other urban interventions and other approach the real estate market. The research used as instruments interviews with actors who work in the property market in the town and representatives of organizations that have implemented major legislation in the area, the Instituto de Patrimônio Histórico e Artístico Nacional (IPHAN) and the Secretaria de Meio Ambiente e Urbanismo (SEMURB) as well as photographs on the area, in order to verify this new configuration that has been consolidated in the district. To support the theoretical discussion, there was a documentary and bibliographical research. In this way, the object of study of this search sees the uniqueness of urban renewal in the district of Ribeira and its relationship with the historic preservation laws and incentives for residential occupation in the neighborhood, especially regarding the vertical building

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Gossypium mustelinum Miers ex Watt is the only cotton species native from Brazil. It is endemic of the semi-arid region from North-east of the country, where it occur near from resilient water sources. The threats to the in situ conservation of the populations are caused by human interference in its habitat, mainly by excessive cattle graze and deforestation. Establish efficient strategies of in situ conservation depend on the accomplishment of a diagnosis of how the specie is found in its natural environment, and the knowledge about the genetic structure of the populations. The objectives of this work were i) to determine the in situ conditions of two populations present in rivers from basin of Rio Paraguaçu at the Bahia State, ii) to evaluate the structure and genetic variability presented in both populations, iii) to establish in situ and ex situ conservation strategies. It were realized collection in november 2007, when was realized in situ characterization of G. mustelinum. SSR markers were used for analyze 218 genotypes deriving from two populations of the G. mustelinum, localized at Tocó river and the Capivara river. The allelic frequencies, the heterozigosity and the F statics were estimated. All the plants were classified as wild and natives, and there was no evidence of the use the plants or its parts. The populations showed different conservation conditions in situ. Few plantlets were found in sites with excessive cattle feed, an indication that the damages in young plants should be high enough to compromise the renovation of the populations. On the other hand, populations were well preserved when the anthropic damages was low or inexistent. The 14 SSR primer pairs amplified 17 loci with a medium number of 5 alleles per locus (a total of 85 alleles). The high level of endogamy estimated (FIS=0,808) and the low observed heterozygosity (H0=0,093) were indicatives that the populations reproduce mainly by selfing, geitonogamy and crosses between related individuals. The genetic diversity was high (HE=0,482) and the differentiation between the populations was very high (FST=0,328). At least two sites from both populations of G. mustelinum must be preserved to achieve suitable in situ conservation. Actions that preserve the gallery forest and keep the cattle away should implemented, and could be as simple as erecting a fence. It is not possible anticipated if the in situ preservation will be possible. Therefore collections and ex situ preservation of representative specimens are essential to conserve the genetic diversity of native G. mustelinum

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Over the last 50 years a new research area, science education research, has arisen and undergone singular development worldwide. In the specific case of Brazil, research in science education first appeared systematically 40 years ago, as a consequence of an overall renovation in the field of science education. This evolution was also related to the political events taking place in the country. We will use the theoretical work of Rene Kaes on the development of groups and institutions as a basis for our discussion of the most important aspects that have helped the area of science education research develop into an institution and kept it operating as such. The growth of this area of research can be divided into three phases: The first was related to its beginning and early configurations; the second consisted of a process of consolidation of this institution; and the third consists of more recent developments, characterised by a multiplicity of research lines and corresponding challenges to be faced. In particular, we will analyse the special contributions to this study gleaned from the field known as the history and philosophy of science.

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

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

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

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

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Diplopods feed organic matter in decomposition; however, some environmental factors can promote changes in tissues of these animals. Sewage sludge has been applied for recuperation of physical structure of degraded soil. This work analyzed the influence of the sludge from a city of So Paulo in the midgut of the diplopod Rhinocricus padbergi. After the exposition to sludge, the midgut was prepared for histological and ultra-structural analyses. After 1 week of exposition, there were various glycoprotein globules in the fat body, which appeared, ultrastructurally, little electron dense. In the animals exposed for 2 weeks, there was an intensive renovation of the epithelium with the invasion of regenerative cells, which was observed in the histological and ultra-structural analyses. These data showed that the sludge present various substances that were very hazardous for these animals; more studies were necessary before the application of this in agriculture.

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The female prostate has aroused scientific interest because it is subjected to the same diseases compromising the male prostate during aging. The objective of this work was to characterize structurally, cytochemically, and ultrastructurally the tissue compartments of the normal adult female prostate of Meriones unguiculatus gerbils. The morphological analyses showed that the gerbil's female prostate is constituted of a cluster of glands and ducts inserted in a musculofibrous stroma. The alveolar epithelium is differentiated and consisted of basal proliferating cells, intermediary cells, and secretory cells. The secretory cells are the most numerous cell type and continuously secrete glycoproteins. The basal cells are the source of the secretory cells and they are then responsible for the alveolus renovation. The prostatic stroma is abundant and rich in elastic and collagen fibers, which are closely associated with smooth muscle cells and fibroblasts. The results showed that the gerbil's female prostate shows morphological and ultrastructural homology to the human female prostate (Skene's gland), and despite being a small organ, it is a mature and physiologically active gland. (C) 2003 Elsevier Ltd. All rights reserved.

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O artigo aborda as teorias dos Hazards e dos Desastres. Nos últimos anos estas duas tradições teóricas têm recebido novos impulsos pela renovação de seus marcos de referência conceitual. Construídas em torno de uma longa tradição de pesquisa empírica, estas teorias explicam os impactos provocados por fenômenos como enchentes, terremotos, tornados e epidemias mediante a integração analítica das dimensões natural e social. Neste sentido, seu estudo pode fornecer subsídios para a interpretação destes problemas no Brasil.

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During the past decade, influenced strongly by World Bank land policies, many governments instituted a new mode of recreating the peasantry, one supposedly led by market forces through credit programs secured by land. Supported by large landowner organizations, defended as a conquest by the rural labor movement and combated by member organizations of the Via Campesina, the new mode of peasant renovation has inspired a diversity of interpretations both positive and negative. To evaluate these events, this article seeks to demonstrate the World Bank's intentionality in urging the implementation of market-led agrarian reform in developing countries; discusses the construction of immaterial territories in the context of this policy; analyzes the development of a people's think tank in response to the agitation of the Via Campesina Brazil and the negative impact of the credit system on peasants.

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Soil tillage and other methods of soil management may influence CO 2 emissions because they accelerate the mineralization of organic carbon in the soil. This study aimed to quantify the CO2 emissions under conventional tillage (CT), minimum tillage (MT) and reduced tillage (RT) during the renovation of sugarcane fields in southern Brazil. The experiment was performed on an Oxisol in the sugarcane-planting area with mechanical harvesting. An undisturbed or no-till (NT) plot was left as a control treatment. The CO2 emissions results indicated a significant interaction (p < 0.001) between tillage method and time after tillage. By quantifying the accumulated emissions over the 44 days after soil tillage, we observed that tillage-induced emissions were higher after the CT system than the RT and MT systems, reaching 350.09 g m-2 of CO2 in CT, and 51.7 and 5.5 g m-2 of CO2 in RT and MT respectively. The amount of C lost in the form of CO2 due to soil tillage practices was significant and comparable to the estimated value of potential annual C accumulation resulting from changes in the harvesting system in Brazil from burning of plant residues to the adoption of green cane harvesting. The CO 2 emissions in the CT system could respond to a loss of 80% of the potential soil C accumulated over one year as result of the adoption of mechanized sugarcane harvesting. Meanwhile, soil tillage during the renewal of the sugar plantation using RT and MT methods would result in low impact, with losses of 12% and 2% of the C that could potentially be accumulated during a one year period. © 2013 IOP Publishing Ltd.