821 resultados para Prism


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In order to gain knowledge from large databases, scalable data mining technologies are needed. Data are captured on a large scale and thus databases are increasing at a fast pace. This leads to the utilisation of parallel computing technologies in order to cope with large amounts of data. In the area of classification rule induction, parallelisation of classification rules has focused on the divide and conquer approach, also known as the Top Down Induction of Decision Trees (TDIDT). An alternative approach to classification rule induction is separate and conquer which has only recently been in the focus of parallelisation. This work introduces and evaluates empirically a framework for the parallel induction of classification rules, generated by members of the Prism family of algorithms. All members of the Prism family of algorithms follow the separate and conquer approach.

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Prism is a modular classification rule generation method based on the ‘separate and conquer’ approach that is alternative to the rule induction approach using decision trees also known as ‘divide and conquer’. Prism often achieves a similar level of classification accuracy compared with decision trees, but tends to produce a more compact noise tolerant set of classification rules. As with other classification rule generation methods, a principle problem arising with Prism is that of overfitting due to over-specialised rules. In addition, over-specialised rules increase the associated computational complexity. These problems can be solved by pruning methods. For the Prism method, two pruning algorithms have been introduced recently for reducing overfitting of classification rules - J-pruning and Jmax-pruning. Both algorithms are based on the J-measure, an information theoretic means for quantifying the theoretical information content of a rule. Jmax-pruning attempts to exploit the J-measure to its full potential because J-pruning does not actually achieve this and may even lead to underfitting. A series of experiments have proved that Jmax-pruning may outperform J-pruning in reducing overfitting. However, Jmax-pruning is computationally relatively expensive and may also lead to underfitting. This paper reviews the Prism method and the two existing pruning algorithms above. It also proposes a novel pruning algorithm called Jmid-pruning. The latter is based on the J-measure and it reduces overfitting to a similar level as the other two algorithms but is better in avoiding underfitting and unnecessary computational effort. The authors conduct an experimental study on the performance of the Jmid-pruning algorithm in terms of classification accuracy and computational efficiency. The algorithm is also evaluated comparatively with the J-pruning and Jmax-pruning algorithms.

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Dual-polarisation radar measurements provide valuable information about the shapes and orientations of atmospheric ice particles. For quantitative interpretation of these data in the Rayleigh regime, common practice is to approximate the true ice crystal shape with that of a spheroid. Calculations using the discrete dipole approximation for a wide range of crystal aspect ratios demonstrate that approximating hexagonal plates as spheroids leads to significant errors in the predicted differential reflectivity, by as much as 1.5 dB. An empirical modification of the shape factors in Gans's spheroid theory was made using the numerical data. The resulting simple expressions, like Gans's theory, can be applied to crystals in any desired orientation, illuminated by an arbitrarily polarised wave, but are much more accurate for hexagonal particles. Calculations of the scattering from more complex branched and dendritic crystals indicate that these may be accurately modelled using the new expression, but with a reduced permittivity dependent on the volume of ice relative to an enclosing hexagonal prism.

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The oscillatory electro-oxidation of methanol was studied by means of in situ infrared (IR) spectroscopy in the attenuated total reflection (ATR) configuration using a platinum film on a Si prism as working electrode. The surface-enhanced infrared absorption (SEIRA) effect considerably improves the spectroscopic resolution, allowing at following the coverage of some adsorbing species during the galvanostatic oscillations. Carbon monoxide was the main adsorbed specie observed in the induction period and within the oscillatory regime. The system was investigated at two distinct time-scales and its dynamics characterized accordingly. During the induction period the main transformation observed as the system move through the phase space towards the oscillatory region was the decrease of the coverage of adsorbed carbon, coupled to the increase of the electrode potential. Similar transition characterizes the evolution within the oscillatory region, but at a considerably slower rate. Experiments with higher time resolution revealed that the electrode potential oscillates in-phase with the frequency of the linearly adsorbed CO vibration and that the amount of adsorbed CO oscillates with small amplitude. Adsorbed formate was found to play, if any, a very small role. Results are discussed and compared with other systems. (C) 2010 Elsevier B.V. All rights reserved.

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This work tries to comprehend, throw the prism of the Institutional Theory, the structural process of organizational field of cachaça¿s handicraft producers¿ from a Brazilian countryside region. The role of values and traditions on the determination of the structure and decision making on this industry are analyzed. It is necessary to research historic, economic and social facts, and confront them to the formation of Brazilian society to understand the field¿s formulation. An important aspect of this research is the mapping of isomorphic process and the comparison of the field¿s institutional degree, before and after the changes. It was noticed that the alteration on perception of Cachaça in the national market and the entrance of a new actor oriented by functional rationality are the major reasons for the mimetic changes on this field. As a contribution, this study confirms the applicability of Institutional Theory on analysis of specific fields and shows how this field has structured itself.

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O gado zebu (Bos indicus) é predominante em todo o mundo. Atualmente, no Brasil, o rebanho de bovinos e zebuínos é composto por aproximadamente 170 milhões de indivíduos, no qual, 80% são zebuínos ou animais de raças cruzadas com zebu. O principal objetivo deste estudo foi determinar a possibilidade da utilização de marcadores moleculares de bovinos na identificação genética de zebuínos. A confirmação desta possibilidade seria de extrema valia, já que a quantidade de informações sobre o genoma zebuíno é limitada e metodologias específicas de identificação de marcadores genéticos para raças zebuínas são raras. Assim, o DNA de 65 zebus, de 4 raças diferentes (Gir, Tabapuã, Nelore e Brahman), foi extraído a partir de sangue aplicado em papel filtro, utilizando o “kit” DNA IQTM SYSTEM (Promega®). Após a extração de DNA, foi feito um PCR Multiplex utilizando o “kit” StockMarks® (Applied Biosystems®), o qual amplifica um total de 11 loci (BM1824, BM2113, ETH10, ETH225, ETH3, INRA023, SPS115, TGLA122, TGLA126, TGLA227 e TGLA53). Os fragmentos gerados pela PCR foram analisados por eletroforese capilar utilizando o analisador genético ABI Prism 3100 (Applied Biosystems®) e o programa GeneScan® v.3.7 (Applied Biosystems®). A freqüência dos marcadores e os índices de variabilidade genética foram calculados utilizando o programa Microsatellite Toolkit v.3.1 e o equilíbrio de Hardy-Weinberg foi determinado através do programa GENEPOP v.3.4. Através destas técnicas foi possível demonstrar que os marcadores moleculares utilizados para identificação genética de bovinos podem também ser utilizados para a realização da técnica de identificação genética de zebuínos Além disso, foi possível demonstrar a freqüência alélica na população de zebuínos analisada como um todo, assim como foi determinada a freqüência alélica para os diferentes marcadores moleculares dentro das 4 raças estudas. Considerando o total de 100 diferentes alelos identificados entre os 11 STR (Short Tandem Repeats) analisados, foi possível observar que a heterozigosidade esperada (He) foi relativamente alta na população analisada, assim como na análise por raça. Estes dados indicam alto grau de diversidade genética nas diferentes raças. Neste sentido, a raça Brahman apresentou a menor diversidade (0,60) e a raça Tabapuã, a maior (0,69). Contudo, estudos complementares são necessários, a fim de confirmar as freqüências alélicas estabelecidas, uma vez que os resultados encontrados no presente trabalho referem-se a um número relativamente pequeno de zebuínos, quando comparados com o total de zebus encontrados no rebanho brasileiro.

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O que nos move!!! Nos dias de hoje, é fundamental que as organizações públicas se posicionem na vanguarda da tecnologia para enfrentarem a exigência, cada vez mais crescente, da população. O ambiente em que vivemos se caracteriza por ser altamente dinâmico. A cada dia, os constantes processos de mudança nos apresentam novos problemas, novas responsabilidades. Este trabalho tem como proposta explorar um tema delicado para as organizações públicas: as informações gerenciais. Um dos problemas da administração pública é justamente a imensa quantidade de informações que se podem fazer disponíveis a um administrador. A grande questão é como selecionar e organizar, dentro dessa disponibilidade, aquelas informações realmente úteis. o assunto "Processo Decisório" é muito abrangente e, o enfoque da necessidade de informações também já foi amplamente discutido. Entretanto, esta dissertação pretende observar as informações gerenciais e os sistemas de informações por um outro prisma, que será o da inserção destas ferramentas dentro das esferas governamentais, como apoio à tomada de decisão e a transparência da gestão pública. Este enfoque ressalta a importância e demonstra a viabilidade de se implantar sistemas de informações gerenciais. O tema teve como objeto de análise, o Sistema de Informações Gerenciais da Controladoria Geral do Município do Rio de Janeiro.

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Este trabalho aborda questões referentes ao patrocínio cultural no Brasil, com foco naquele relacionado ao setor público, no âmbito das ações de comunicação social. Trata-se de um levantamento dos temas que envolvem a elaboração, a gestão e a tramitação de um projeto de patrocínio, sobretudo a partir da perspectiva de contribuir para uma reflexão sobre os significados de determinadas terminologias e conceitos usados nesse campo. O objetivo é que o resultado do trabalho sirva como base de informações que possam fomentar reflexões sobre o patrocínio cultural no setor público, mais especificamente no que se refere a questões de terminologias e conceitos, num campo onde ainda há poucos parâmetros de padronizações estabelecidos no que se refere à linguagem e a entendimentos sobre processos de gestão. Numa etapa conclusiva da dissertação, é apresentado um glossário de verbetes de patrocínio que pretende se prestar como uma boa memória dos nomes e das significações que merecem destaque.

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The subject Responsibility Enterprise Social (RSE) is relatively recent in the half national academic and the world of the management businesses as practical. For the lack of socialization of experiences and clarity of concepts, shunting lines in the agreement of the subject and the conduction of the interventions occur. It was looked to inquire, in this research, the development of the project of Social Responsibility Enterprise ―School of Computer science and Citizenship‖ of a situated company in the State of Pará, objectifying to evaluate it and later to understand it. For this, one searched to describe the characteristics and structure of the School, to identify to the lines and lines of direction adopted for this Project and to identify to the influence and results of the same in the life of pupils, professors and egresses of the School. It is characterized for a study of case with qualitative boarding of descriptive character, carried through interviews structuralized in a sample of 21 divided members of the School between professors, pupils and egresses. It was used of the analysis of categorical content, having as axle for the interpretation of the data the Social Responsibility, the Digital Inclusion and the Education. The gotten results inform that the infrastructure has challenges to face, point disparities between the conception and practical of the categories characterized in the Politician-Pedagogical Project of the EIC and the influence that, exactly under limits, the life of the professors, pupils reaches and egress. One evidenced that Social action for damages of this company when come back toward this project, they had not been evidenced. For this prism, these actions had only remained in the assistencialist speech and not structural, being thus, the company is not fulfilling its paper of transforming element of the reality of its clientele and the population that lives in it s around

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Background: Leprosy can cause severe disability and disfigurement and is still a major health in different parts of the world. Only a subset of those individuals exposed to the pathogen will go on to develop clinical disease and there is a broad clinical spectrum amongst leprosy patients. The outcome of infection is in part due to host genes that influence control of the initial infection and the host´s immune response to that infection. Aim: Evaluate if polymorphisms type SNP in the 17q118q21 chromosomic region contribute to development of leprosy in Rio Grande do Norte population. Material and methods: A sample composed of 215 leprosy patients and 229 controls drawn from the same population were genotyped by using a Snapshot assay for eight genes (NOS2A, CCL18, CRLF3, CCL23, TNFAIP1, STAT5B, CCR7 and CSF3) located in chromosomic region 17q118q21. The genotype and allele frequency were measured and statistical analysis was performed by chi-square in SPSS version 15 and graph prism pad version 4 software. Results: Ours results indicated that the markers NOS2A8277, NOS2A8rs16949, CCR78rs11574663 and CSF38rs2227322 presented strong association with leprosy and their risk genotype were GG, TT, AA and GG respectively. The risk genotypes for all markers associated to leprosy presented recessive inheritance standard. When we compared the interaction among the markers in different combination we find that the marker NOS2A8277 associated with CCR78rs11574663 presented highest risk probability to development of leprosy. When we evaluated the haplotype of the risk markers it was found a haplotype associated with increase of the protection (CSF38rs22273228CC, CCR78 rs115746638GA, NOS2A8rs169498CT and NOS2A82778GA). The association of the clinical forms paucibacilary and multibacilary with markers showed that to the markers NOS2A8 2778GG, CCR78rs115746638AA and CSF38rs22273228GG there were a strong influence to migration to multibacilary pole and to marker NOS2A8rs169498TT the high proportion was found to the paucibacilary form. Conclusions: Changes in the genes NOS2A, CCR7 and CSF3 can influence the immune response against Mycobacterium leprae. The combination among these polymorphisms alters the risk probability to develop leprosy. The markers type SNP associated to development of the leprosy also are linked to clinical forms and its severity being the polymorphism NOS2A8rs169498TT associated with paucibacilar form and the polymorphisms NOS2A82778GG, CCR78rs115746638AA and CSF38rs22273228GG associated to multibacilar form

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Human mesenchymal stem cells (MSC) are powerful sources for cell therapy in regenerative medicine. The long time cultivation can result in replicative senescence or can be related to the emergence of chromosomal alterations responsible for the acquisition of tumorigenesis features in vitro. In this study, for the first time, the expression profile of MSC with a paracentric chromosomal inversion (MSC/inv) was compared to normal karyotype (MSC/n) in early and late passages. Furthermore, we compared the transcriptome of each MSC in early passages with late passages. MSC used in this study were obtained from the umbilical vein of three donors, two MSC/n and one MSC/inv. After their cryopreservation, they have been expanded in vitro until reached senescence. Total RNA was extracted using the RNeasy mini kit (Qiagen) and marked with the GeneChip ® 3 IVT Express Kit (Affymetrix Inc.). Subsequently, the fragmented aRNA was hybridized on the microarranjo Affymetrix Human Genome U133 Plus 2.0 arrays (Affymetrix Inc.). The statistical analysis of differential gene expression was performed between groups MSC by the Partek Genomic Suite software, version 6.4 (Partek Inc.). Was considered statistically significant differences in expression to p-value Bonferroni correction ˂.01. Only signals with fold change ˃ 3.0 were included in the list of differentially expressed. Differences in gene expression data obtained from microarrays were confirmed by Real Time RT-PCR. For the interpretation of biological expression data were used: IPA (Ingenuity Systems) for analysis enrichment functions, the STRING 9.0 for construction of network interactions; Cytoscape 2.8 to the network visualization and analysis bottlenecks with the aid of the GraphPad Prism 5.0 software. BiNGO Cytoscape pluggin was used to access overrepresentation of Gene Ontology categories in Biological Networks. The comparison between senescent and young at each group of MSC has shown that there is a difference in the expression parttern, being higher in the senescent MSC/inv group. The results also showed difference in expression profiles between the MSC/inv versus MSC/n, being greater when they are senescent. New networks were identified for genes related to the response of two of MSC over cultivation time. Were also identified genes that can coordinate functional categories over represented at networks, such as CXCL12, SFRP1, xvi EGF, SPP1, MMP1 e THBS1. The biological interpretation of these data suggests that the population of MSC/inv has different constitutional characteristics, related to their potential for differentiation, proliferation and response to stimuli, responsible for a distinct process of replicative senescence in MSC/inv compared to MSC/n. The genes identified in this study are candidates for biomarkers of cellular senescence in MSC, but their functional relevance in this process should be evaluated in additional in vitro and/or in vivo assays

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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This dissertation deals with the possibility of build an effective social control of the judiciary Brazilians. The theme was bounded by a cut geographic and secular: the experience of the Center of Justice and Citizenship in the state of Rio Grande do Norte (OJC/RN), which begins formally in august 2003. The research approach and leave of experience in judicial practice and policy specific substrates to theorize about the subject. We collected documents about cases, the judicial diagnoses, reports, news material, in addition to lifting bibliographic. Therefore, it is working with about notions of a democratic state of right in the light of the Brazilian Constitution of 1988, in order to contextualize the insertion of the judicial system, by the prospect of legitimacy, which is considered by a look formal and material. It is a brief analysis of the system of official control of the judiciary (internal and external), is emphasizing its shortcomings functional and its corporate character, which suffers from poor conformation democratic. Then there is a discussion about the need to establish the social control of the judiciary, through the prism of relations of power that are locked in the judiciary, the lack of formal criteria for the guarantee of obtaining the correct judgment (laws, precedents and conscience of the judge), the problems of impunity and justice class, and from the examination of some cases, as the body of search. From this conjuncture, prepares to be an outline of shapes and the limits of social control, consonant the proposal erected in certain sectors of organized civil society, represented by the movement s social OJC. In the end, considerations are made on the legitimacy and constitutionality of OJC