903 resultados para Continuing formation. Science teaching. Content of astronomy
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Processo FAPESP: 12/15101-4
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A atualização dos currículos escolares e, em especial, a inserção de assuntos de física moderna e contemporânea já foram defendidos com justificativas satisfatórias, tanto por professores em atividade escolar como por pesquisadores da área de ensino de física. Entre os assuntos que deveriam ser discutidos encontramos a Física das Partículas Elementares. O ensino deste tópico é justificado pelo fato dele permitir a discussão: a) de uma nova visão de mundo; b) de uma visão mais adequada da ciência; c) da reinterpretação da Física Clássica; d) da dinâmica da Ciência e seu desenvolvimento; e) da contribuição dos diversos cientistas; f) do papel da experimentação; g) do investimento financeiro e cooperativo de diversos países e pesquisadores. No entanto, para que a inserção de assuntos de física moderna e contemporânea ocorra de maneira eficiente é necessária a atualização dos professores que já estão em docência escolar, bem como uma formação adequada daqueles que estão em processo de formação inicial. Neste sentido, desde 2010 a Sociedade Brasileira de Física realiza anualmente a Escola de Física do CERN, na qual participam professores brasileiros de física de escolas públicas do Ensino Médio. Nesta escola são desenvolvidas aulas sobre física de partículas, sessões experimentais e visitas aos laboratórios do CERN. Perante isso, investigamos como os professores participantes da Escola de Física do CERN abordam a física de partículas em suas aulas após participarem dela.
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Recent studies have shown a positive association of cancer and obesity, but the morphological and molecular mechanisms involved in this relationship are still unknown. This study analysed the impact of long-term obesity on rat prostate, focusing on stromal changes. Male adult Wistar rats were treated with high-fat diet to induce obesity, while the control group received a balanced diet. After 30 weeks of feeding, the ventral prostate was analysed by immunohistochemistry for cell proliferation, smooth muscle α-actin, vimentin, chondroitin sulphate and metalloproteinases (MMP-2 and 9). The content of androgen receptor (AR), oestrogen receptors (ERs) and vascular endothelial growth factor (VEGF) was measured by Western blotting, and activity of catalase and Glutathione-S-Transferase (GST) were quantified by enzymatic assay. Long-term obesity decreased testosterone plasma levels by 70% and resulted in stromal prostate hyperplasia, as evidenced by increased collagen fibres. Such stromal hyperplasia was associated with increased number of blood vessels and raised VEGF content, and increased expression of chondroitin sulphate, vimentin, α-actin and MMP-9. In spite of the high cell density in prostate, the proliferative activity was lower in the prostates of obese rats, indicating that hyperplasia was established during the early phases in this obesity model. AR levels increased significantly, whereas the ERα decreased in this group. Moreover, the levels of catalase and GST were changed considerably. These findings indicate that long-term obesity, besides disturbing the antioxidant control, causes intense stromal remodelling and release of factors that create an environment that can promote proliferative disorders in the gland, culminating with diffuse hyperplasia.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The consumption of carotenoid-rich vegetables such as tomatoes and tomato sauces is associated with reduced risk of several chronic diseases. The predominant carotenoids in tomato products are in the (all-E) configuration, but (Z) isomers can be formed during thermal processing. The effect of cooking time (15, 30, 45 and 60 min) and the addition of extra virgin olive oil (5% and 10%) on the carotenoid extractability of tomato sauces was monitored using liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) and LC-ultraviolet detection (LC-UV). The thermal treatment and the addition of extra virgin olive oil increased the levels of antioxidant activity, total carotenoids, Z-lycopene isomers, -carotene and -carotene. These results are of particular nutritional benefit since higher lycopene intake has been associated with a reduced risk of lethal prostate and a reduction of prostate-specific antigen (PSA) levels. Moreover, -carotene has been reported to suppress the up-regulation of heme oxygenase-1 gene expression in a dose dependent manner and to suppress UVA-induced HO-1 gene expression in cultured FEK4.
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An expression for the U(3) content of the matrix elements of one- and two-body operators in Elliott's basis is obtained. Three alternative ways of evaluating this content with increasing performance in computing time are presented. All of them allow an exact representation of that content in terms of integers, avoiding Founding errors in the computer codes. The role of dual bases in dealing with nonorthogonal bases is also clarified. © 1992 American Institute of Physics.
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Purpose: In the present work, a susceptibility and efficacy of the Ti–7.5Mo alloy and Ti alloy to bacterial biofilm formation after surface treatment was evaluated. Methods and materials: The alloy Ti–7.5Mo was obtained in arc furnace under an argon atmosphere. Ingots were then homogenized under vacuum at 1100 °C for 86.4 ks to eliminate chemical segregation and after cold worked discs were cutting. Samples were immersed in NaOH aqueous solution (5 M) and treated at 450 °C. Biofilms were grown in Ti–7.5Mo discs immersed in sterile brain heart infusion broth (BHI)containing 5% sucrose, inoculated with microbial suspension (106 cells/ml) and incubated for 5 days. Next, the discs were placed in tubes with sterile physiological solution 0.9% sodium chloride (NaCl) and sonicated for to disperse the biofilms. Tenfold serial dilutions were carried and aliquots seeded in selective agar, which were then incubated for 48 h. Then, the numbers CFU/ml (log 10) were counted and analyzed statistically. Scanning electron microscopy (SEM) on discs with biofilms groups was performed, atomic force microscope (AFM) and contact angle. Results: The results show that there is a 5% difference in bacterial adhesion between pure titanium and Ti–7.5Mo alloy. Conclusion: It was concluded that the greater the roughness, the greater the hydrophilic effect.
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Specific dietary contents from six fishes collected in Mississippi Sound are recorded. In order of their importance, primary components grouped in major taxonomic categories were fishes, penaeid shrimps, and other crustaceans for Cynoscion nebulosus; Crustaceans and fishes for C. arenarius; fishes and crustaceans for C. nothus; crustaceans, pelecypods, and polychaetes for Pogonias cromis; crustaceans, molluscs, polychaetes, and fishes for Archosargus probatocephalus; and fishes and penaeid shrimps for Paralichthys lethostigma. Principal items in the diets of most of the fishes included Anchoa mitchilli, Penaeus aztecus, P. setiferus, and Callinectes sapidus. Those crustaceans show that competition exists for commercial shellfishes in Mississippi Sound. Ratios among the different dietary items vary, according at least to species of fish, length of fish, season, specific location, and abundance of available prey. Some of these variations are documented and are additionally related to selected findings by other authors sampling different localities. We suggest that examination of food items in Archosargus probatocephalus can serve as a practical means to sample and assess seasonal prevalence and abundance of a wide range of invertebrates throughout different habitats in Mississippi Sound and elsewhere.
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This study compares information-seeking behavior of Bachelor of Science and Master of Science students in the fields of agricultural extension and education. The authors surveyed Iranian students in departments of agricultural extension and education at four universities in Tehran, Shiraz, Mollasani, and Kermanshah. This study focused on three aspects: (1) comparison of amounts of information-seeking behavior between Bachelor of Science and Master of Science agricultural extension and education students; (2) comparison of information-seeking behavior varieties in Bachelor of Science and Master of Science agricultural extension and education students; (3) Comparison of amounts of available information resources at four universities and its effectiveness on students' information-seeking behavior; and (4) comparison of research and educational outputs in Bachelor of Science and Master of Science students. Scale free technique, division by mean method, principal components analysis technique, Delphi method, t-test, correlation and regression tools were used for data analysis. This study revealed that Bachelor of Science students' information-seeking behavior is for improving educational output, but Master of Science students' information-seeking behavior is for promoting research output. Among varieties of Internet searching skills, library searching skills, and awareness of library information-seeking methods with students' information-seeking behavior, there are not significant differences between two groups of students.
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The purpose of this study was to compare the inorganic content and morphology of one nanofilled and one nanohybrid composite with one universal microhybrid composite. The Vickers hardness, degree of conversion and scanning electron microscope of the materials light-cured using LED unit were also investigated. One nanofilled (Filtek (TM) Supreme XT), one nanohybrid (TPH (R) 3) and one universal microhybrid (Filtek (TM) Z-250) composite resins at color A2 were used in this study. The samples were made in a metallic mould (4 mm in diameter and 2 mm in thickness). Their filler weight content was measured by thermogravimetric analysis (TG). The morphology of the filler particles was determined using scanning electron microscope equipped with a field emission gun (SEM-FEG). Vickers hardness and degree of conversion using FT-IR spectroscopy were measured. Filtek (TM) Z-250 (microhybrid) composite resin shows higher degree of conversion and hardness than those of Filtek (TM) Supreme XT (nanofilled) and TPH (R) 3 (nanohybrid) composites, respectively. The TPH3 (R) (nanohybrid) composite exhibits by far the lowest mechanical property. Nanofilled composite resins show mechanical properties at least as good as those of universal hybrids and could thus be used for the same clinical indications as well as for anterior restorations due to their high aesthetic properties. Microsc. Res. Tech. 75:758765, 2012. (C) 2011 Wiley Periodicals, Inc
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The effects of domestic cooking on proteins, organic compounds and Fe distribution in beans (Phaseolus vulgaris L.) were investigated. Sequential extraction with different extractant solutions (mixture of methanol and chloroform 1:2 v/v, water, 0.5 mol L-1 NaCl, 70% v/v ethanol and 0.5 mol L-1 NaOH) were used for extracting lipids, albumins, globulins, prolamins and glutelins, respectively. Iron determination by graphite furnace atomic absorption spectrometry (GF AAS), proteins by Bradford method and organic compounds by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) were carried out in this work. High concentration of albumins, globulins and glutelins were found in raw beans, while in the cooked beans, albumins and glutelins are main proteins types. The MALDI-TOF MS spectra of raw and cooked beans revealed that the domestic cooking altered the molecular weight of the organic compounds, since that in the cooked beans were found compounds between 2 and 3.5 kDa, which were not presented in the raw beans. Besides this, in cooked beans were also observed the presence of four compounds of high molecular weight (12-16 kDa), being that in the raw grains there is only one (ca. 15.2 kDa). In raw grains is possible to observe that Fe is mainly associated to albumins, globulins and glutelins. For cooked grains, Fe is associated to albumins and globulins.
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LDL oxidation and oxidative stress are closely related to atherosclerosis. Therefore, natural antioxidants have been studied as promising candidates. In the present study, the LDL oxidation inhibition activity of bioactive compounds from Halimeda incrassata seaweed. associated to antioxidant capacity, was evaluated in vitro. Experimental work was conducted with lyophilized aqueous extract and phenolic-rich fractions of the seaweed and their effect on LDL oxidation was evaluated using heparin-precipitated LDL (hep-LDL) with exposure to Cu2+ ions and AAPH as the free radical generator. H. incrassata had a protective effect for hep-LDL in both systems and the presence of phenolic compounds contributed to the activity where phenolic-rich fractions showed significant capacity for inhibition of oxidation mediated by Cu2+ ions. The observed effect could be related to the antioxidant potential of polar fractions evidenced by reducing activity and DPPH center dot radical scavenging. The results obtained in vitro further support the antioxidant and LDL oxidation inhibition properties of H. incrassata and further knowledge toward future phytotherapeutic application of the seaweed.