859 resultados para Tobacco in literature


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Enzymes have been widely used in biosynthesis/transformation of organic compounds in substitution the classic synthetic methods. This work is the first writing in literature of enzymatic synthesis for attainment the biossurfactants, the use glucose sucrose, ricinoleic acid e castor oil as substratum, and as biocatalyst, used immobilized lipase Thermomyces lanuginose, Rhizomucor miehei and the Candida antarctica lipase B; alkaline protease and neutral protease from Bacillus subtillis and yeast Saccharomyces cerevisiaeI. The analysis of HPLC (high performance liquid chromatography) showed that highest conversions were reached of used the alkaline protease from Bacillus subtillis. Laboratory tests, to evaluate the applicability, indicated that the produced biosurfactantes had good stability in presence of salts (NaCl) and temperature (55 e 25°C), they are effective in the reduction of the superficial tension and contac angle, but they have little foaming capacity, when compared with traditional detergents. These results suggest that the prepared surfactants have potential application as wetting agent and perforation fluid stabilizer

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

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Investments in health have controversial influence on results of the health of populations, besides being subject rarely explored in literature. Moreover, from the 1970s, the social determinants of health have been consolidated in the disease process as multifactorial factors (social, economic, cultural, etc.) that directly or indirectly influence the occurrence of health problems of populations, as well as mortality rates. This study aimed to evaluate the influence of these investments and the social determinants of health on infant mortality and its neonatal and post-neonatal mortality. This is an ecological study, in which the sample was composed of Brazilians cities with over 80,000 inhabitants, avoiding fluctuations in mortality rates for common small populations, and ensure greater coverage of information systems on mortality and births Brazilians and, therefore, increase data consistency. To isolate the effect of investments in health, we used multiple linear regression. The socioeconomic indicators (p <0.001, p = 0.004, p <0.001), the inequality index (p <0.001, p = 0.001, p = 0.006) and coverage of prenatal visits (p <0.001, p <0.001; p = 0.005) were associated with infant mortality rate total, neonatal and post-neonatal, and the Gross Domestic Product per capita only influenced the overall infant mortality rate and neonatal (p=0.022; 0.045). Investments in health, in this model, lost statistical significance, showing no correlation with mortality rates among children under one year. We conclude that the social determinants of health has an influence on the variation in mortality rates of Brazilian cities, however the same was not observed for indicators of health investment

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O fungo Sclerotium rolfsii causa grandes perdas em algumas culturas econômicas. Por produzir estruturas de resistência (escleródios), este fungo é de difícil controle. Há escassez de novos ingredientes ativos eficientes para o controle deste patógeno. Assim, o objetivo do presente trabalho foi verificar se existe atividade fungitóxica na planta Momordica charantia (melão-de-sãocaetano), com potencial futuro para ser estudado no controle de S. rolfsii. Para isso, dois ensaios foram realizados, um in vitro (laboratório) e outro in vivo (câmara de crescimento). em in vitro, escleródios do patógeno ficaram em contato com extratos hidroetanólico e aquoso de folhas e ramos de M. charantia e sem extrato por 7, 14, 21 e 28 dias. A sobrevivência dos escleródios foi avaliada em meio de cultura específico, após cada tempo. em in vivo, testou-se a ação dos mesmos extratos de maneira preventiva e curativa (aplicação aos 6 e 3 dias antes do plantio; no dia do plantio; e aos 3 e 6 dias após o plantio) e no tratamento de semente, no patossistema feijoeiro cv. Carioquinha versus S. rolfsii. A eficiência da ação dos extratos foi avaliada por meio da severidade da doença. Os extratos hidroetanólico e aquoso, in vitro, de forma semelhante, controlaram 100% os escleródios, num período de 0 a 7 dias. No ensaio in vivo, o extrato hidroetanólico, aplicado tanto em 6 ou 3 dias, antes do plantio, de forma preventiva, diminuiu a severidade da doença em 74%. Há atividade fungitóxica na parte aérea da planta de melão-de-são-caetano, com potencial futuro de estudo para controlar S. rolfsii, preferencialmente, de maneira preventiva.

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The Quadratic Minimum Spanning Tree Problem (QMST) is a version of the Minimum Spanning Tree Problem in which, besides the traditional linear costs, there is a quadratic structure of costs. This quadratic structure models interaction effects between pairs of edges. Linear and quadratic costs are added up to constitute the total cost of the spanning tree, which must be minimized. When these interactions are restricted to adjacent edges, the problem is named Adjacent Only Quadratic Minimum Spanning Tree (AQMST). AQMST and QMST are NP-hard problems that model several problems of transport and distribution networks design. In general, AQMST arises as a more suitable model for real problems. Although, in literature, linear and quadratic costs are added, in real applications, they may be conflicting. In this case, it may be interesting to consider these costs separately. In this sense, Multiobjective Optimization provides a more realistic model for QMST and AQMST. A review of the state-of-the-art, so far, was not able to find papers regarding these problems under a biobjective point of view. Thus, the objective of this Thesis is the development of exact and heuristic algorithms for the Biobjective Adjacent Only Quadratic Spanning Tree Problem (bi-AQST). In order to do so, as theoretical foundation, other NP-hard problems directly related to bi-AQST are discussed: the QMST and AQMST problems. Bracktracking and branch-and-bound exact algorithms are proposed to the target problem of this investigation. The heuristic algorithms developed are: Pareto Local Search, Tabu Search with ejection chain, Transgenetic Algorithm, NSGA-II and a hybridization of the two last-mentioned proposals called NSTA. The proposed algorithms are compared to each other through performance analysis regarding computational experiments with instances adapted from the QMST literature. With regard to exact algorithms, the analysis considers, in particular, the execution time. In case of the heuristic algorithms, besides execution time, the quality of the generated approximation sets is evaluated. Quality indicators are used to assess such information. Appropriate statistical tools are used to measure the performance of exact and heuristic algorithms. Considering the set of instances adopted as well as the criteria of execution time and quality of the generated approximation set, the experiments showed that the Tabu Search with ejection chain approach obtained the best results and the transgenetic algorithm ranked second. The PLS algorithm obtained good quality solutions, but at a very high computational time compared to the other (meta)heuristics, getting the third place. NSTA and NSGA-II algorithms got the last positions

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O presente artigo investiga como A teoria do romance (1916) de G. Lukács, um texto fragmentado e de ocasião, tornou-se um clássico da reflexão sobre a modernidade. Para Lukács, o romance é a forma artística que corresponde à fratura entre o sujeito e o mundo, vivida pelo homem contemporâneo. Utilizando o conceito de símbolo esvaziado este texto apreende em que medida o autor ao rever as classificações anteriores sobre o gênero romance, perpetua a tradição romântica ou rompe com ela, elaborando conceitos originais para a compreensão da modernidade na literatura.

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

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The use of intelligent agents in multi-classifier systems appeared in order to making the centralized decision process of a multi-classifier system into a distributed, flexible and incremental one. Based on this, the NeurAge (Neural Agents) system (Abreu et al 2004) was proposed. This system has a superior performance to some combination-centered methods (Abreu, Canuto, and Santana 2005). The negotiation is important to the multiagent system performance, but most of negotiations are defined informaly. A way to formalize the negotiation process is using an ontology. In the context of classification tasks, the ontology provides an approach to formalize the concepts and rules that manage the relations between these concepts. This work aims at using ontologies to make a formal description of the negotiation methods of a multi-agent system for classification tasks, more specifically the NeurAge system. Through ontologies, we intend to make the NeurAge system more formal and open, allowing that new agents can be part of such system during the negotiation. In this sense, the NeurAge System will be studied on the basis of its functioning and reaching, mainly, the negotiation methods used by the same ones. After that, some negotiation ontologies found in literature will be studied, and then those that were chosen for this work will be adapted to the negotiation methods used in the NeurAge.

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The main goal of this work is to investigate the suitability of applying cluster ensemble techniques (ensembles or committees) to gene expression data. More specifically, we will develop experiments with three diferent cluster ensembles methods, which have been used in many works in literature: coassociation matrix, relabeling and voting, and ensembles based on graph partitioning. The inputs for these methods will be the partitions generated by three clustering algorithms, representing diferent paradigms: kmeans, ExpectationMaximization (EM), and hierarchical method with average linkage. These algorithms have been widely applied to gene expression data. In general, the results obtained with our experiments indicate that the cluster ensemble methods present a better performance when compared to the individual techniques. This happens mainly for the heterogeneous ensembles, that is, ensembles built with base partitions generated with diferent clustering algorithms

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Os tumores malignos do canal anal e do anus são muito raros, não ultrapassam 2% de todos os tumores do colo, reto e anus; segundo os principais levantamentos os melanomas não ultrapassam a incidência de 0,1 a 1,2% dos tumores malignos. Os autores descrevem 2 casos de melanoma, discutindo os principais dados da literatura, enfocando os aspectos diagnósticos, tratamento, evolução e prognostico. Os indicies de cura s são baixos e com elevados índices de mortalidade a curto prazo.

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The techniques of Machine Learning are applied in classification tasks to acquire knowledge through a set of data or information. Some learning methods proposed in literature are methods based on semissupervised learning; this is represented by small percentage of labeled data (supervised learning) combined with a quantity of label and non-labeled examples (unsupervised learning) during the training phase, which reduces, therefore, the need for a large quantity of labeled instances when only small dataset of labeled instances is available for training. A commom problem in semi-supervised learning is as random selection of instances, since most of paper use a random selection technique which can cause a negative impact. Much of machine learning methods treat single-label problems, in other words, problems where a given set of data are associated with a single class; however, through the requirement existent to classify data in a lot of domain, or more than one class, this classification as called multi-label classification. This work presents an experimental analysis of the results obtained using semissupervised learning in troubles of multi-label classification using reliability parameter as an aid in the classification data. Thus, the use of techniques of semissupervised learning and besides methods of multi-label classification, were essential to show the results

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The objective of this dissertation is the development of a general formalism to analyze the thermodynamical properties of a photon gas under the context of nonlinear electrodynamics (NLED). To this end it is obtained, through the systematic analysis of Maxwell s electromagnetism (EM) properties, the general dependence of the Lagrangian that describes this kind of theories. From this Lagrangian and in the background of classical field theory, we derive the general dispersion relation that photons must obey in terms of a background field and the NLED properties. It is important to note that, in order to achieve this result, an aproximation has been made in order to allow the separation of the total electromagnetic field into a strong background electromagnetic field and a perturbation. Once the dispersion relation is in hand, the usual Bose-Einstein statistical procedure is followed through which the thermodynamical properties, energy density and pressure relations are obtained. An important result of this work is the fact that equation of state remains identical to the one obtained under EM. Then, two examples are made where the thermodynamic properties are explicitly derived in the context of two NLED, Born-Infelds and a quadratic approximation. The choice of the first one is due to the vast appearance in literature and, the second one, because it is a first order approximation of a large class of NLED. Ultimately, both are chosen because of their simplicity. Finally, the results are compared to EM and interpreted, suggesting possible tests to verify the internal consistency of NLED and motivating further developement into the formalism s quantum case

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The Cumuruxatiba basin is located at the southern coast State of Bahia in northeastern of Brazil. This basin was formed in distensional context, with rifting and subsequent thermal phase during Neocomian to late Cretaceous. At Cenozoic ages, the Abrolhos magmatism occurs in the basin with peaks during the Paleocene and Eocene. In this period, there was a kinematic inversion in the basin represented by folds related to reverse faults. Structural restoration of regional 2D seismic sections revealed that most of the deformation was concentrated at the beginning of the Cenozoic time with the peak at the Lower Eocene. The post-Eocene is marked by a decrease of strain rate to the present. The 3D structural modeling revealed a fold belt (trending EW to NE-SW) accommodating the deformation between the Royal Charlotte and Sulphur Minerva volcanic highs. The volcanic eruptions have caused a differential overburden on the borders of the basin. This acted as the trigger for halokinesis, as demonstrated by physical modeling in literature. Consequently, the deformation tends to be higher in the edges of the basin. The volcanic rocks occur mainly as concordant structures (sills) in the syn-tectonic sediment deposition showing a concomitant deformation. The isopach maps and diagrams of axis orientation of deformation revealed that most of the folds were activated and reactivated at different times during the Cenozoic. The folds exhibit diverse kinematic patterns over time as response to behavior of adjacent volcanic highs. These interpretations allied with information on the petroleum system of the basin are important in mapping the prospects for hydrocarbons

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Thirty-four consecutive adult patients with subdural traumatic hygroma were analysed for clinical evolution, serial computed tomography scan (CT), and magnetic resonance imaging (MRI) over a period of several months. Five of the patients presented CT scan and MRI evolution data showing increasing density over a period of 11 days to 6 months post trauma. In these five patients, final clinical and CT scan data were benign, with complete spontaneous resolution. Descriptions in literature of evolving traumatic subdural hygroma have presented CT scan density modifications changing into chronic subdural hematoma. Our patients show another possibility, density transformation, which sometimes show as subdural hematoma in CT scan and MRI, but with final evolution where clinical condition and CT scan return to normal.

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INTRODUÇÃO: O objetivo deste trabalho foi analisar a prevalência do uso de drogas por estudantes da Faculdade de Medicina de Botucatu - Unesp, comparada com outras oito escolas médicas paulistas (uso na vida, nos últimos 12 meses e nos últimos 30 dias). A pesquisa foi realizada entre 1994 e 1995, com 5.227 estudantes do 1o ao 6o ano de graduação. MATERIAL E MÉTODO: Foi usado um questionário de auto-respostas, anônimo, incluindo o questionário da Organização Mundial da Saúde para levantamento de uso de drogas e álcool. Setenta e um por cento (3.725) dos alunos responderam ao mesmo, e destes, 421 eram de Botucatu. RESULTADOS: Não houve diferenças estatisticamente significantes entre escolas e, nos 30 dias anteriores ao preenchimento do questionário, a prevalência do uso de drogas para os estudantes de Botucatu foi a seguinte, com a variação entre outras escolas mostrada entre parênteses: álcool 50% (42-50%); tabaco 7% (7-13%); solventes 8% (7-12%); maconha 6% (6-16%); benzodiazepínicos (BZD) 3% (2-9%); cocaína 0,5% (0,2-4%); anfetaminas 1 % (0-1%). Embora tenha se encontrado um uso crescente de todas as drogas do 1o ao 6o ano, e em especial os BZD, os estudantes não aprovam este uso. A análise de regressão logística indicou que o uso de álcool e drogas foi favorecido por: a) ser homem; b) perder aulas sem razão e referir ou ter muito tempo livre nos finais de semana; e c) ter uma atitude favorável em relação ao uso de álcool e drogas. Diferentemente de outras escolas, na Unesp não houve diferenças estatisticamente significantes de gênero em relação ao uso de tranqüilizantes. No entanto, as mulheres iniciam uso mais precocemente e o fazem mais freqüentemente. Também as mulheres já faziam uso de maconha antes de entrar para a faculdade (30% mulheres X 10% homens), o contrário ocorrendo com solventes (50% homens X 2% mulheres), sendo essas diferenças estatisticamente significantes. CONCLUSÕES: Embora a pesquisa tenha focalizado o uso (não abuso ou dependência), os resultados sugerem a necessidade de as universidades estabelecerem uma política clara de orientação sobre uso de drogas e álcool para os estudantes, incluindo mudanças curriculares e programas de prevenção.