900 resultados para Trigonometry. Astronomy. Historical sources. Use of historical sources in classrooms


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. The aim of this study was to artificially feed partially engorged Dermacentor (Anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. The technique of artificial feeding through plastic tips allowed the engorgement of D. nitens ticks to a final weight within the normal range for the species. (C) 2014 Published by Elsevier GmbH.

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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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O trabalho escolar pode ser concebido como o resultado de complexas relações entre as prescrições legais, os diversos atores e as condições materiais da realidade objetiva de determinada escola, apresentando diferentes dimensões que condicionam seu desenvolvimento, envolvendo aspectos de natureza organizacionalestrutural e de natureza político-ideológica. O presente trabalho é resultado do curso de extensão realizado com professoras de ciências naturais de uma rede escolar pública municipal. Utilizando a abordagem de pesquisa qualitativa do tipo estudo de caso, objetivamos identificar os principais condicionantes que atuam sobre o trabalho docente e que são responsáveis pela baixa frequência de utilização de atividades experimentais. Os condicionantes identificados no estudo realizado se enquadraram em quatro fatores: relacionados à organização da escola e das aulas; ligados às condições estruturais e materiais; relacionados ao professor; e relacionados ao comportamento do aluno.

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This work aimed to compare the predictive capacity of empirical models, based on the uniform design utilization combined to artificial neural networks with respect to classical factorial designs in bioprocess, using as example the rabies virus replication in BHK-21 cells. The viral infection process parameters under study were temperature (34°C, 37°C), multiplicity of infection (0.04, 0.07, 0.1), times of infection, and harvest (24, 48, 72 hours) and the monitored output parameter was viral production. A multilevel factorial experimental design was performed for the study of this system. Fractions of this experimental approach (18, 24, 30, 36 and 42 runs), defined according uniform designs, were used as alternative for modelling through artificial neural network and thereafter an output variable optimization was carried out by means of genetic algorithm methodology. Model prediction capacities for all uniform design approaches under study were better than that found for classical factorial design approach. It was demonstrated that uniform design in combination with artificial neural network could be an efficient experimental approach for modelling complex bioprocess like viral production. For the present study case, 67% of experimental resources were saved when compared to a classical factorial design approach. In the near future, this strategy could replace the established factorial designs used in the bioprocess development activities performed within biopharmaceutical organizations because of the improvements gained in the economics of experimentation that do not sacrifice the quality of decisions.

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The diffuse esophageal spasm distinguishes from others esophageal disturbs by the symptoms severity and bad results to conservative treatment. This situation requires formal indication to surgical treatment or dilation. In high risk patients this situation becomes a big problem, due to the lack of another therapeutic option. In a patient with this problem we use an endoscopic injection of botulin toxin in cardia with good results in three months follow-up. Despite this short period of observation we believe that the infiltration with botulin toxin in cardia constitutes a valid therapeutic option in treatment of diffuse esophageal spasm.

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Two compost formulations, based on Braquiaria straw (Brachiaria sp.), a conventional one and a spent one, were tested in the cultivation of ABL 99/30 and ABL 04/49 strains of Agaricus blazei. The experimental design was in a completely randomized factorial scheme with four treatments (two strains of A. blazei x two types of compost) and 30 repetitions. Each experimental unit consisted of a box with 10 to 10.5 kg of moist fresh compost. According to the results obtained, the loss of organic matter of the composts was affected by the A. blazei strain and the type of compost used. The traditional compost lost a higher organic matter content compared to the spent compost, and the ABL 99/30 strain caused a higher loss of organic matter in the composts compared to the ABL 04/49 strain. Yield, biological efficiency, mass and number of basidiomata produced were similar between the conventional and the spent compost, as well as the chemical analysis of the produced basidiomata. However, the A. blazei strains showed some differences among each other, the basidiomata of strain ABL 04/49 obtained a higher percentage of crude protein in their composition, compared to the ABL 99/30, in both composts. Thus, the utilization of spent compost in the cultivation of A. blazei did not impair the basidiomata yield nor their nutritional value, demonstrating it to be a good option to be used as an ingredient in the compost formulation for the A. blazei cultivation.

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Top predators in the marine environment integrate chemical signals acquired from their prey that reflect both the species consumed and the regions from which the prey were taken. These chemical tracers—stable isotope ratios of carbon and nitrogen; persistent organic pollutant (POP) concentrations, patterns and ratios; and fatty acid profiles—were measured in blubber biopsy samples from North Pacific killer whales (Orcinus orca) (n = 84) and were used to provide further insight into their diet, particularly for the offshore group, about which little dietary information is available. The offshore killer whales were shown to consume prey species that were distinctly different from those of sympatric resident and transient killer whales. In addition, it was confirmed that the offshores forage as far south as California. Thus, these results provide evidence that the offshores belong to a third killer whale ecotype. Resident killer whale populations showed a gradient in stable isotope profiles from west (central Aleutians) to east (Gulf of Alaska) that, in part, can be attributed to a shift from off-shelf to continental shelf-based prey. Finally, stable isotope ratio results, supported by field observations, showed that the diet in spring and summer of eastern Aleutian Island transient killer whales is apparently not composed exclusively of Steller sea lions.

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Top predators in the marine environment integrate chemical signals acquired from their prey that reflect both the species consumed and the regions from which the prey were taken. These chemical tracers—stable isotope ratios of carbon and nitrogen; persistent organic pollutant (POP) concentrations, patterns and ratios; and fatty acid profiles—were measured in blubber biopsy samples from North Pacific killer whales (Orcinus orca) (n = 84) and were used to provide further insight into their diet, particularly for the offshore group, about which little dietary information is available. The offshore killer whales were shown to consume prey species that were distinctly different from those of sympatric resident and transient killer whales. In addition, it was confirmed that the offshores forage as far south as California. Thus, these results provide evidence that the offshores belong to a third killer whale ecotype. Resident killer whale populations showed a gradient in stable isotope profiles from west (central Aleutians) to east (Gulf of Alaska) that, in part, can be attributed to a shift from off-shelf to continental shelf-based prey. Finally, stable isotope ratio results, supported by field observations, showed that the diet in spring and summer of eastern Aleutian Island transient killer whales is apparently not composed exclusively of Steller sea lions.

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Factor analysis was used to develop a more detailed description of the human hand to be used in the creation of glove sizes; currently gloves sizes are small, medium, and large. The created glove sizes provide glove designers with the ability to create a glove design that can provide fit to the majority of hand variations in both the male and female populations. The research used the American National Survey (ANSUR) data that was collected in 1988. This data contains eighty-six length, width, height, and circumference measurements of the human hand for one thousand male subjects and thirteen hundred female subjects. Eliminating redundant measurements reduced the data to forty-six essential measurements. Factor analysis grouped the variables to form three factors. The factors were used to generate hand sizes by using percentiles along each factor axis. Two different sizing systems were created. The first system contains 125 sizes for male and female. The second system contains 7 sizes for males and 14 sizes for females. The sizing systems were compared to another hand sizing system that was created using the ANSUR database indicating that the systems created using factor analysis provide better fit.

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Aliquat 336, a liquid hydrophobic material, was used at different concentrations (0.5-3.0%, w/v) as an additive in the preparation of encapsulated lipase from Bacillus sp. ITP-001 on sol-gel silica matrices using tetraethoxysilane (TEOS) as the precursor. The resulting hydrophobic matrices and immobilized lipases were characterized with regard to specific surface area (BET method), adsorption-desorption isotherms, pore volume (Vp) and size (dp) by nitrogen adsorption (BJH method) and scanning electron microscopy (SEM). The catalytic activities and the corresponding coupling yields were assayed in the hydrolysis of olive oil. In comparison with pure silica matrices, the immobilization process in the presence of Aliquat 336 decreased the values for specific surface area and increased the values for pore specific volume (Vp) and mean pore diameter (dp). This behavior may be related to the partial adsorption of the enzyme on the external surface of the hydrophobic matrix as indicated by scanning electron microscopy. Aliquat 336 concentrations in the range from 0.5 to 1.5% (w/v) provided immobilized derivatives with higher coupling yields and better substrate affinity. The highest coupling yield (Y-A = 71%) was obtained for the immobilized enzyme prepared in the presence of 1.5% Aliquat which gave the following morphological properties: specific surface area = 183 m(2)/g, pore specific volume (Vp) = 0.36 cc/g and mean pore diameter (dp)= 91 angstrom. (c) 2012 Elsevier B.V. All rights reserved.

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