987 resultados para Respostas não medidas


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Environmental sustainability has become one of the topics of greatest interest in industry, mainly due to effluent generation. Phenols are found in many industries effluents, these industries might be refineries, coal processing, pharmaceutical, plastics, paints and paper and pulp industries. Because phenolic compounds are toxic to humans and aquatic organisms, Federal Resolution CONAMA No. 430 of 13.05.2011 limits the maximum content of phenols, in 0.5 mg.L-1, for release in freshwater bodies. In the effluents treatment, the liquid-liquid extraction process is the most economical for the phenol recovery, because consumes little energy, but in most cases implements an organic solvent, and the use of it can cause some environmental problems due to the high toxicity of this compound. Because of this, exists a need for new methodologies, which aims to replace these solvents for biodegradable ones. Some literature studies demonstrate the feasibility of phenolic compounds removing from aqueous effluents, by biodegradable solvents. In this extraction kind called "Cloud Point Extraction" is used a nonionic surfactant as extracting agent of phenolic compounds. In order to optimize the phenol extraction process, this paper studies the mathematical modeling and optimization of extraction parameters and investigates the effect of the independent variables in the process. A 32 full factorial design has been done with operating temperature and surfactant concentration as independent variables and, parameters extraction: Volumetric fraction of coacervate phase, surfactant and residual concentration of phenol in dilute phase after separation phase and phenol extraction efficiency, as dependent variables. To achieve the objectives presented before, the work was carried out in five steps: (i) selection of some literature data, (ii) use of Box-Behnken model to find out mathematical models that describes the process of phenol extraction, (iii) Data analysis were performed using STATISTICA 7.0 and the analysis of variance was used to assess the model significance and prediction (iv) models optimization using the response surface method (v) Mathematical models validation using additional measures, from samples different from the ones used to construct the model. The results showed that the mathematical models found are able to calculate the effect of the surfactant concentration and the operating temperature in each extraction parameter studied, respecting the boundaries used. The models optimization allowed the achievement of consistent and applicable results in a simple and quick way leading to high efficiency in process operation.

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

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This work relates our experience in an investigative practice in the classroom, carried out in State School Jorge Fernandes , located in Natal - RN, having as objective to validate the applying of a education module about Measures and Largenesses in Primary Teaching. We used the constructivist approach; using to Richard s Skemp (1980) theory in order to explicit the students learning according to their comprehension levels. Initially, we carry out an exploratory research to check the participant s previous knowledge. Then, we developed an intervention to validate an education module, structured from needs pointed out from results of the initial research, analyzing the students advances through the final evaluation, displaying growth stages of group front to the knowledge about the matter approached. Finally, we presented our reflections about our experience; putting forward suggestions of the teachers activities, aiming at contributing to the improvement of their practices in classroom during the approach of subject for us investigated

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This present research the aim to show to the reader the Geometry non-Euclidean while anomaly indicating the pedagogical implications and then propose a sequence of activities, divided into three blocks which show the relationship of Euclidean geometry with non-Euclidean, taking the Euclidean with respect to analysis of the anomaly in non-Euclidean. PPGECNM is tied to the line of research of History, Philosophy and Sociology of Science in the Teaching of Natural Sciences and Mathematics. Treat so on Euclid of Alexandria, his most famous work The Elements and moreover, emphasize the Fifth Postulate of Euclid, particularly the difficulties (which lasted several centuries) that mathematicians have to understand him. Until the eighteenth century, three mathematicians: Lobachevsky (1793 - 1856), Bolyai (1775 - 1856) and Gauss (1777-1855) was convinced that this axiom was correct and that there was another geometry (anomalous) as consistent as the Euclid, but that did not adapt into their parameters. It is attributed to the emergence of these three non-Euclidean geometry. For the course methodology we started with some bibliographical definitions about anomalies, after we ve featured so that our definition are better understood by the readers and then only deal geometries non-Euclidean (Hyperbolic Geometry, Spherical Geometry and Taxicab Geometry) confronting them with the Euclidean to analyze the anomalies existing in non-Euclidean geometries and observe its importance to the teaching. After this characterization follows the empirical part of the proposal which consisted the application of three blocks of activities in search of pedagogical implications of anomaly. The first on parallel lines, the second on study of triangles and the third on the shortest distance between two points. These blocks offer a work with basic elements of geometry from a historical and investigative study of geometries non-Euclidean while anomaly so the concept is understood along with it s properties without necessarily be linked to the image of the geometric elements and thus expanding or adapting to other references. For example, the block applied on the second day of activities that provides extend the result of the sum of the internal angles of any triangle, to realize that is not always 180° (only when Euclid is a reference that this conclusion can be drawn)

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Teaching and learning representations have been more and more investigated in the Brazilian applied linguistics field, as it allows the understanding of the teachers representations and how they conceive the learning process. This practice facilitates the planning of actions to improve the educational system. This study aims at identifying, interpreting and discussing some representations related to the identity and professional view of English as a foreign language teachers in different school contexts of Natal-RN. The theoretical and methodological foundation for this research is Halliday s Systemic- Functional Linguistics (1994; HALLIDAY; MATHIESSEN, 2004; EGGINS, 1994, among others). Our goal was to reveal the teachers representations embedded in their language, mainly through the ideational metafunction, as language is the tool we use to express ourselves about the external world (events, qualities, things, etc) and the internal world (thoughts, beliefs, feelings, etc). The research corpus is made of 21 teacher narratives, generated from a questionnaire sent to the teachers, who were divided in two groups: Group 1 (public schools teachers) and Group 2 (private schools and English course teachers). Most of the participants seemed to be satisfied with their professional choice. Many of them see the job as a challenge and an opportunity to transmit knowledge. All of them affirmed that the English teacher is a professional, for different reasons; however, the low professional appreciation was a recurrent aspect among the studied narratives. When asked about where they work, the private school teachers seemed to be more satisfied with the teaching-learning process than the ones from the public schools. We believe that the data analyzed in this study is important to show how some English teachers from Natal-RN see their profession. The results might be used in continuing education courses as food-for-thought in group discussions, as it is extremely important to emphasize and stimulate this practice

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

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The philosophical discussion has been present throughout the whole history of reason, for philosophy and reason have been always closely linked. In the following work, Reason, origin, crises and contemporary answers I go into the history of the rational and demonstrative thought, focusing on how rationality can be thought about in contemporary philosophy. To answer this question I discuss the principle of philosophy, the mythical period and the thoughts of Heraclito , Parmenides , Plato and Aristotle in relation to reason and rationality. Also discussed is the medieval period and the philosophical use of logic and the criticism of Aristotle s thoughts, especially focusing on the criticism of Hegel and Luckasiewicz of the non contradiction principle. Lastly I discuss the development of reason in present day philosophy, mainly how modern logics could be putting at stake Aristotle s model of reason

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In the 20th century, the acupuncture has spread on occident as a complementary practice of heath care. This fact has motivated the international scientific community to invest in research that seek to understand why acupuncture works. In this work we compare statistically volt age fluctuation of bioelectric signals caught on the skin at an acupuncture point (IG 4) another nearby on acupuncture point. The acquisition of these signals was performed utilizing an electronic interface with a computer, which was based on an instrumentation amplifier designed with adequate specifications to this end. On the collected signals from a sample of 30 volunteers we have calculated major statistics and submitted them to pairing t-test with significance leveI a = O, 05. We have estimated to bioelectric signals the following parameters: standard deviation, asymmetry and curtose. Moreover, we have calculated the self-correlation function matched by on exponential curve we have observed that the signal decays more rapidly from a non-acupoint then from an acupoint. This fact is an indicative of the existence of information in the acupoint

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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O objetivo desta pesquisa foi investigar se o repertório de habilidades sociais importantes para a formação ética de um grupo de estudantes de ensino médio, curso pré-vestibular e curso de graduação em psicologia evidenciava mudanças relacionadas à diferença de idade e características específicas dos contextos interativos oferecidos pelas instituições de ensino participantes desse processo. Foi aplicado o Inventário de Habilidades Sociais a uma amostra de 45 estudantes e questionários semiestruturados a nove professores. Entre os alunos, os resultados indicaram diferença estatisticamente significativa entre as classes das categorias de ensino investigadas em relação a diferentes conjuntos de habilidades sociais. Dos resultados obtidos com os professores, pode-se depreender que estes possuem noção clara das capacidades que o aluno deve obter para agir com ética e ser cidadão, mas esses professores não propiciam condições, no contexto escolar, para a promoção de tais habilidades. Isso indicou a necessidade de melhorias na capacitação dos docentes, visando à ampliação do repertório de habilidades sociais de seus alunos.

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Constata-se uma carência de instrumentos que avaliem habilidades sociais de crianças da educação infantil, de modo a predizer problemas comportamentais e instrumentar ações preventivas, justificando a proposição de instrumentos. Objetivou-se testar propriedades psicométricas de validade e confiabilidade do Questionário de Respostas Socialmente Habilidosas para pais (QRSH-Pais). Foram avaliados por suas mães 131 pré-escolares, diferenciados em subgrupos com e sem problema de comportamento com base na Escala Comportamental Infantil (ECI-Pais e ECI-Professor). Procedeu-se aos estudos de validade discriminativa e concorrente e a verificação da consistência interna pelo alfa de Cronbach. Os resultados apontaram para indicadores positivos de consistência interna e validade discriminativa. Considera-se que o questionário está aferido para avaliação de habilidades sociais em pré-escolares, podendo ser utilizado em pesquisas de avaliação e de intervenção clínica controlada.

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The production of forage grasses is directly related to the morphogenesis. The knowledge of the morphogenetic and structural variables of forage plants is important for determining appropriate conditions of grazing livestock to ensure efficient and sustainable. Thus the objective of this study was to evaluate morphogenetic and structural responses of three genera of grasses, Brachiaria, Panicum and Cenchrus in a cutting regime. The experimental design was randomized blocks with three replications and six treatments. After each section were evaluated for forage production, appearance and elongation rates of leaves and stem, phyllochron, final leaf length, number of living leaves, leaf lifespan, leaf senescence rate, tiller density and tiller dynamics. On forage yield the highest values were obtained in cultivars Xaraes, Piata and Massai. The tiller density was higher for cv Massai. It is concluded that the cultivars of Panicum and Brachiaria had a higher tillering dynamics in increasing the turnover rate of tissues that are indicators of forage production, assuming that the cultivars of these genera are predisposed to use forage in the Northeast

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Regarding the growing number of human beings with physical and mental pathologies associated to different stressor agents, attempts are being made to validate animal models with a close phylogenetic resemblance to man, to study stress response. Callithrix jacchus has been widely used in biomedical research, including on stress, but there is scarce information in the literature about how individual and social factors modulate stressor response in this species. This study uses 4 approaches to investigate the response of male and female adult C. jacchus, under situations of stress, and in the first we show evidence of the importance of this animal as an experimental model in research involving the hypothalamus-pituitary-adrenal axis. And we investigate if sex and baseline cortisol levels modulate the behavioral and hormonal response to separation. In two additional approaches investigate if type of social support (co-specific parent or non-parent) and social rank interfere in behavioral and hormonal when the animal are exposure to a new environment, paired with a co-specific (F2), exposure of the animal to a new environment, isolated (F3) or during reunion (F4). Finally, we also investigated the androgen levels in the males, with a focus on the challenge hypothesis, referring to environmental responsiveness and male-male exposure to relatives and non-relatives of C. jacchus. It was observed that: (1) the baseline cortisol of the animal is predictive of cortisol reactivity at separation; (2) males and females do not show dimorphism in the response of cortisol to stressors, although the females have higher baseline levels of this hormone and exhibit higher frequencies of anxiety-related behaviors; (3) only social support provided by relatives proved to be effective in buffering the cortisol response. In behavioral terms this response was dimorphic, showing that only the male dyads displayed an attenuated response to stress; (4) the males showed differences in cortisol levels as a function of social rank and study phases, whereas in the females no such alterations were observed. The males with indefinite dominance hierarchy (IDH) had reduced cortisol in F2 and F4, while the IDH females showed an increase in F3 and F4; (5) the males of relative and non-relative dyads did not exhibit variations in androgen levels as a function of a new environment. These results, taken together, (a) corroborate the use of C. jacchus as a good animal model for stress-related studies, given that they exhibit similar behavioral and physiological alterations to those of human beings in response to stressor agents; (b) point to the importance of considering individual and social modulating factors during experiments with stressors; (c) provide more reliable comparison parameters in studies where these primates are used as animal models, and (d) show that androgens vary as a function of genetic proximity (relative or non-relative) when the animals are faced with physical and social environmental challenges, thus providing important information for studying the challenge hypothesis in this species

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Social behavior of Guiana dolphins, Sotalia guianensis, at Pipa Beach, RN, Brazil: dynamics, sequence, breathing synchrony, and responses to dolphin watching. Social animals form groups that can range from temporary to permanent. Depending on the nature of the social relationships developed between individuals, groups present a particular social organization and the effect of these interactions shapes the activity patterns of these animals. This study investigates: (i) fission-fusion dynamics of Guiana dolphins, through the analysis of three dimensions of the social system (variation in spatial cohesion, variation in size and composition of groups), (ii) sequence, routine and behavioral stability, (iii) breathing intervals in synchronized groups and (iv) behavioral responses of the animals to dolphin watching. Systematic observations of Guiana dolphins were made from a platform located in cliffs about 25 m above sea level that surround Madeiro Bay, Pipa Beach. Sampling occurred from December 2007 to February 2009 between 0600 h and 1600 h, and the groups of Guiana dolphins were investigated according to their size (alone and group) and composition (adults, adults and juveniles, and adults and calves). According to the analysis of fission-fusion dynamics, Guiana dolphin groups frequently changed their composition, modifying their patterns of spatial grouping and cohesion every 20 minutes on average. More than 50% of the individuals maintained a distance of up to 2 m from other group members and new individuals were attracted to the group, especially during feeding, leaving it for foraging. Large groups were more unstable than small, while groups containing only adults were more stable than groups of adults and juveniles. According to the Z-score analysis to investigate the sequence and behavioral routine, lone individuals were more ! .7! ! involved in foraging and feeding, while resting was more common in groups. Foraging and feeding were more common in homogeneous groups (individuals of the same age class), while heterogeneous groups (different age classes) were often involved in socialization, displaying a broader behavioral repertoire. Foraging and resting behavior presented higher stability (continuous duration in minutes) than the other behaviors. The analysis of breathing intervals in synchronized groups showed significant differences depending on type of behavior, composition and area preference. During resting, breathing intervals were of longer duration, and groups with calves showed shorter breathing intervals than groups without calves. Lone individuals also preferred areas called corral , often used for the entrapment of fishes. The Markov chain analysis revealed behavioral changes in the presence of boats, according to the type of group composition. Groups composed of adults presented decreased resting and increased in traveling during the presence of boats. Groups of adults and juveniles showed a massive reduction of socialization, while the behavior transition probability traveling-traveling was higher in groups of adults and calves. In the presence of the boats, stability of resting was reduced by one third of its original duration and traveling more than doubled. The behavioral patterns analyzed are discussed in light of socio-ecological models concerning costs and benefits of proximity between individuals and behavioral optimization. Furthermore, significant changes in behavioral patterns indicate that Guiana dolphins, at Pipa Beach, have suffered the effects of tourism as a result of violation of rules of conduct established for the study area

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Objetivou-se estudar as medidas de espessura de gordura subcutânea, área de olho-de-lombo, comprimento e profundidade máxima do músculo longissimus dorsi entre a 13ª costela e 1ª vértebra lombar determinadas por ultrassom e na carcaça de ovelhas de descarte abatidas em diferentes estágios fisiológicos, além dos coeficientes de correlação e determinação das medidas avaliadas. Utilizaram-se 21 ovelhas da raça Santa Inês, distribuídas nos seguintes grupos: OL = ovelhas que permaneceram por 60 dias em lactação com seus cordeiros e foram abatidas um dia após o desmame dos mesmos; OSC = ovelhas que permaneceram por 60 dias em lactação com seus cordeiros e mais 30 dias sem os cordeiros e foram posteriormente abatidas; e ONP = ovelhas que não pariram durante o ano. O comprimento máximo do músculo longissimus dorsi obtido pelo ultrassom e na carcaça dos animais não foi influenciado pelos estágios fisiológicos. O ultrassom pode ser utilizado com razoável precisão para estimar características da carcaça de ovelhas de descarte, em particular a espessura de gordura subcutânea.