985 resultados para translation studies


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Here we report on the structural, optical, electrical and magnetic properties of Co-doped and (Co,Mo)-codoped SnO2 thin films deposited on r-cut sapphire substrates by pulsed laser deposition. Substrate temperature during deposition was kept at 500 degrees C. X-ray diffraction analysis showed that the undoped and doped films are crystalline with predominant orientation along the [1 0 1] direction regardless of the doping concentration and doping element. Optical studies revealed that the presence of Mo reverts the blue shift trend observed for the Co-doped films. For the Co and Mo doping concentrations studied, the incorporation of Mo did not contribute to increase the conductivity of the films or to enhance the ferromagnetic order of the Co-doped films. (C) 2012 Elsevier B.V. All rights reserved.

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The compounds [mPTA][CoCl4] (1, mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane cation), [CoCl(H2O)(DION)(2)][BF4] (2, DION = 1,10-phenanthroline-5,6-dione), [Zn(DION)(2)]Cl-2 (3) and [ZnCl(O-PTA=O)(DION)][BF4] (4) were synthesized by reaction of CoCl2 with [mPTA]I or DION and ZnCl2 with DION or 1,3,5-triaza-7-phosphaadamantane-7-oxide (PTA=O) and DION, respectively. All complexes are water soluble and have been characterized by IR, far-IR, H-1, C-13 and P-31{H-1} NMR spectroscopy, ESI-MS, elemental analyses and single-crystal X-ray diffraction structural analysis (for 1). They were screened against the human tumour cell lines HCT116, HepG2 and MCF7. Complexes 2 and 3 exhibit the highest in vitro cytotoxicity and show lower cytotoxic activities in normal human fibroblast cell line than in HCT116 tumour cell line, which demonstrates their slight specificity for this type of tumour cell.

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Pregnancy is a dynamic state and the placenta is a temporary organ that, among other important functions, plays a crucial role in the transport of nutrients and metabolites between the mother and the fetus, which is essential for a successful pregnancy. Among these nutrients, glucose is considered a primary source of energy and, therefore, fundamental to insure proper fetus development. Several studies have shown that glucose uptake is dependent on several morphological and biochemical placental conditions. Oxidative stress results from the unbalance between reactive oxygen species (ROS) and antioxidants, in favor of the first. During pregnancy, ROS, and therefore oxidative stress, increase, due to increased tissue oxygenation. Moreover, the relation between ROS and some pathological conditions during pregnancy has been well established. For these reasons, it becomes essential to understand if oxidative stress can compromise the uptake of glucose by the placenta. To make this study possible, a trophoblastic cell line, the BeWo cell line, was used. Experiments regarding glucose uptake, either under normal or oxidative stress conditions, were conducted using tert-butylhydroperoxide (tBOOH) as an oxidative stress inducer, and 3H-2-deoxy-D-glucose (3H-DG) as a glucose analogue. Afterwards, studies regarding the involvement of glucose facilitative transporters (GLUT) and the phosphatidylinositol 3-kinases (PI3K) and protein kinase C (PKC) pathways were conducted, also under normal and oxidative stress conditions. A few antioxidants, endogenous and from diet, were also tested in order to study their possible reversible effect of the oxidative effect of tBOOH upon apical 3H-DG uptake. Finally, transepithelial studies gave interesting insights regarding the apical-to-basolateral transport of 3H-DG. Results showed that 3H-DG uptake, in BeWo cells, is roughly 50% GLUT-mediated and that tBOOH (100 μM; 24h) decreases apical 3H-DG uptake in BeWo cells by about 33%, by reducing both GLUT- (by 28%) and non-GLUT-mediated (by 40%) 3H-DG uptake. Uptake of 3H-DG and the effect of tBOOH upon 3H-DG uptake are not dependent on PKC and PI3K. Moreover, the effect of tBOOH is not associated with a reduction in GLUT1 mRNA levels. Resveratrol, quercetin and epigallocatechin-3-gallate, at 50 μM, reversed, by at least 45%, the effect of tBOOH upon 3H-DG uptake. Transwell studies show that the apical-to-basolateral transepithelial transport of 3H-DG is increased by tBOOH.In conclusion, our results show that tBOOH caused a marked decrease in both GLUT and non-GLUT-mediated apical uptake of 3H-DG by BeWo cells. Given the association of increased oxidative stress levels with several important pregnancy pathologies, and the important role of glucose for fetal development, the results of this study appear very interesting.

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This research work has been focused in the study of gallinaceous feathers, a waste that may be valorised as sorbent, to remove the Dark Blue Astrazon 2RN (DBA) from Dystar. This study was focused on the following aspects: optimization of experimental conditions through factorial design methodology, kinetic studies into a continuous stirred tank adsorber (at pH 7 and 20ºC), equilibrium isotherms (at pH 5, 7 and 9 at 20 and 45ºC) and column studies (at 20ºC, at pH 5, 7 and 9). In order to evaluate the influence of the presence of other components in the sorption of the dyestuff, all experiments were performed both for the dyestuff in aqueous solution and in real textile effluent. The pseudo-first and pseudo-second order kinetic models were fitted to the experimental data, being the latter the best fit for the aqueous solution of dyestuff. For the real effluent both models fit the experimental results and there is no statistical difference between them. The Central Composite Design (CCD) was used to evaluate the effects of temperature (15 - 45ºC) and pH (5 - 9) over the sorption in aqueous solution. The influence of pH was more significant than temperature. The optimal conditions selected were 45ºC and pH 9. Both Langmuir and Freundlich models could fit the equilibrium data. In the concentration range studied, the highest sorbent capacity was obtained for the optimal conditions in aqueous solution, which corresponds to a maximum capacity of 47± 4 mg g-1. The Yoon-Nelson, Thomas and Yan’s models fitted well the column experimental data. The highest breakthrough time for 50% removal, 170 min, was obtained at pH 9 in aqueous solution. The presence of the dyeing agents in the real wastewater decreased the sorption of the dyestuff mostly for pH 9, which is the optimal pH. The effect of pH is less pronounced in the real effluent than in aqueous solution. This work shows that feathers can be used as sorbent in the treatment of textile wastewaters containing DBA.

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Purpose: The aim of this paper is to promote qualitative methodology within the scientific community of management. The specific objective is oriented to propose an empirical research process based on case study method. This is to ensure rigor in the empirical research process, that future research may follow a similar procedure to that is proposed. Design/methodology/approach: Following a qualitative methodological approach, we propose a research process that develops according to four phases, each with several stages. This study analyses the preparatory and field work phases and their stages. Findings: The paper shows the influence that case studies have on qualitative empirical research process in management. Originality/value:. Case study method assumes an important role within qualitative research by allowing for the study and analysis of certain types of phenomena that occur inside organisations, and in respect of which quantitative studies cannot provide an answer.

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OBJETIVO: Obter validade interna, de construto e de critério para a escala Center for Epidemiological Studies - Depression, em idosos. MÉTODOS: O instrumento foi aplicado a 903 idosos residentes em Juiz de Fora, Estado de Minas Gerais, entre os anos de 2002-2003. Os resultados foram comparados com a versão brasileira da Geriatric Depression Scale, aplicado a uma subamostra de 446 respondentes. A consistência interna das duas escalas foi aferida pelo coeficiente alfa de Cronbach, calculado para os itens em sua totalidade e para os itens de cada fator obtido para o instrumento avaliado. Para avaliar a validade de construto, seus 20 itens foram submetidos à análise fatorial exploratória a fim de conhecer o padrão de variação conjunta dos itens e a variância explicada por cada fator. RESULTADOS: O instrumento revelou índices satisfatórios de validade interna (alfa=0,860), sensibilidade (74,6%) e especificidade (73,6%), para nota de corte >11. Entretanto, apontou freqüência relativamente alta de falsos positivos em comparação à Geriatric Depression Scale: de 33,8% vs. 15%. A análise fatorial exploratória do instrumento gerou estrutura fatorial com três fatores: afetos negativos, dificuldades de iniciar comportamentos e afetos positivos. CONCLUSÕES: O instrumento mostrou-se psicometricamente adequado para uso entre idosos. Entretanto, estudos adicionais de natureza longitudinal e transversal, desenvolvidos em diferentes contextos, poderão esclarecer os efeitos de variáveis somáticas e situacionais sobre os resultados desse instrumento em pessoas idosas.

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Background: The eukaryotic release factor 3 (eRF3) has been shown to affect both tubulin and actin cytoskeleton, suggesting a role in cytoskeleton assembly, mitotic spindle formation and chromosome segregation. Also, direct interactions between eRF3 and subunits of the cytosolic chaperonin CCT have been described. Moreover, both eRF3a and CCT subunits have been described to be up-regulated in cancer tissues. Our aim was to evaluate the hypothesis that eRF3 expression levels are correlated with the expression of genes encoding proteins involved in the tubulin folding pathways. Methods: Relative expression levels of eRF1, eRF3a/GSPT1, PFDN4, CCT2, CCT4, and TBCA genes in tumour samples relative to their adjacent normal tissues were investigated using real time-polymerase chain reaction in 20 gastric cancer patients. Results: The expression levels of eRF3a/GSPT1 were not correlated with the expression levels of the other genes studied. However, significant correlations were detected between the other genes, both within intestinal and diffuse type tumours. Conclusions: eRF3a/GSPT1 expression at the mRNA level is independent from both cell translation rates and from the expression of the genes involved in tubulin-folding pathways. The differences in the patterns of expression of the genes studied support the hypothesis of genetically independent pathways in the origin of intestinal and diffuse type gastric tumours.

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The cytosolic chaperonin CCT is a heterooligomeric complex of about 900 kDa that mediates the folding of cytoskeletal proteins. We observed by indirect immunofluorescence that the Tetrahymena TpCCTalpha, TpCCTdelta, TpCCTepsilon, and TpCCTeta-subunits colocalize with tubulin in cilia, basal bodies, oral apparatus, and contractile vacuole pores. TpCCT-subunits localization was affected during reciliation. These findings combined with atomic force microscopy measurements in reciliating cells indicate that these proteins play a role during cilia biogenesis related to microtubule nucleation, tubulin transport, and/or axoneme assembly. The TpCCT-subunits were also found to be associated with cortex and cytoplasmic microtubules suggesting that they can act as microtubule-associated proteins. The TpCCTdelta being the only subunit found associated with the macronuclear envelope indicates that it has functions outside of the 900 kDa complex. Tetrahymena cytoplasm contains granular/globular-structures of TpCCT-subunits in close association with microtubule arrays. Studies of reciliation and with cycloheximide suggest that these structures may be sites of translation and folding. Combined biochemical techniques revealed that reciliation affects the oligomeric state of TpCCT-subunits being tubulin preferentially associated with smaller CCT oligomeric species in early stages of reciliation. Collectively, these findings indicate that the oligomeric state of CCT-subunits reflects the translation capacity of the cell and microtubules integrity.

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It is now widely recognized that translation factors are involved in cancer development and that components of the translation machinery that are deregulated in cancer cells may become targets for cancer therapy. The eukaryotic Release Factor 3 (eRF3) is a GTPase that associates with eRF1 in a complex that mediates translation termination. eRF3a/GSPT1 first exon contains a (GGC)n expansion coding for proteins with different N-terminal extremities. Herein we show that the longer allele (12-GGC) is present in 5.1% (7/137) of the breast cancer patients analysed and is absent in the control population (0/135), corresponding to an increased risk for cancer development, as revealed by Odds Ratio analysis. mRNA quantification suggests that patients with the 12-GGC allele overexpress eRF3a/GSPT1 in tumor tissues relative to the normal adjacent tissues. However, using an in vivo assay for translation termination in HEK293 cells, we do not detect any difference in the activity of the eRF3a proteins encoded by the various eRF3a/GSPT1 alleles. Although the connection between the presence of eRF3a/GSPT1 12-GGC allele and tumorigenesis is still unknown, our data suggest that the presence of the 12-GGC allele provides a potential novel risk marker for various types of cancer.

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The histone deacetylase inhibitors sodium butyrate (NaBu) and trichostatin A (TSA) exhibit anti-proliferative activity by causing cell cycle arrest and apoptosis. The mechanisms by which NaBu and TSA cause apoptosis and cell cycle arrest are not yet completely clarified, although these agents are known to modulate the expression of several genes including cell-cycle- and apoptosis-related genes. The enzymes involved in the process of translation have important roles in controlling cell growth and apoptosis, and several of these translation factors have been described as having a causal role in the development of cancer. The expression patterns of the translation mechanism, namely of the elongation factors eEF1A1 and eEF1A2, and of the termination factors eRF1 and eRF3, were studied in the breast cancer cell line MCF-7 by real-time quantitative reverse transcription-polymerase chain reaction after a 24-h treatment with NaBu and TSA. NaBu induced inhibition of translation factors' transcription, whereas TSA caused an increase in mRNA levels. Thus, these two agents may modulate the expression of translation factors through different pathways. We propose that the inhibition caused by NaBu may, in part, be responsible for the cell cycle arrest and apoptosis induced by this agent in MCF-7 cells.

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This paper aims to present a contrastive approach between three different ways of building concepts after proving the similar syntactic possibilities that coexist in terms. However, from the semantic point of view we can see that each language family has a different distribution in meaning. But the most important point we try to show is that the differences found in the psychological process when communicating concepts should guide the translator and the terminologist in the target text production and the terminology planning process. Differences between languages in the information transmission process are due to the different roles the different types of knowledge play. We distinguish here the analytic-descriptive knowledge and the analogical knowledge among others. We also state that none of them is the best when determining the correctness of a term, but there has to be adequacy criteria in the selection process. This concept building or term building success is important when looking at the linguistic map of the information society.

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Patellid limpets are ecologically important keystone grazers having a long history of overexploitation in the Macaronesian Archipelagos (NE Atlantic islands), where some species, such as Patella aspera, are under serious risk.[1, 2] Patella aspera is a protandric sequential hermaphrodite species with external fertilization, in which individuals start off as males but may undergo a sex reversal with age.[3] Hence, exploitation tends to focus on the larger females in the population as larger limpets (predominantly females) are selectively removed. Despite conservation legislation in Canaries, Madeira and Azores, limpets are under severe pressure and few individuals survive long enough to become females, a phenomenon that severely restricts the effective population size.[4] New conservation actions for the protection and sustainable use of limpets in Macaronesian Archipelagos are urgently needed and should be based on a multidisciplinary framework based on knowledge of the population dynamics and connectivity of this species.

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The main goal of this research study was the removal of Cu(II), Ni(II) and Zn(II) from aqueous solutions using peanut hulls. This work was mainly focused on the following aspects: chemical characterization of the biosorbent, kinetic studies, study of the pH influence in mono-component systems, equilibrium isotherms and column studies, both in mono and tri-component systems, and with a real industrial effluent from the electroplating industry. The chemical characterization of peanut hulls showed a high cellulose (44.8%) and lignin (36.1%) content, which favours biosorption of metal cations. The kinetic studies performed indicate that most of the sorption occurs in the first 30 min for all systems. In general, a pseudo-second order kinetics was followed, both in mono and tri-component systems. The equilibrium isotherms were better described by Freundlich model in all systems. Peanut hulls showed higher affinity for copper than for nickel and zinc when they are both present. The pH value between 5 and 6 was the most favourable for all systems. The sorbent capacity in column was 0.028 and 0.025 mmol g-1 for copper, respectively in mono and tri-component systems. A decrease of capacity for copper (50%) was observed when dealing with the real effluent. The Yoon-Nelson, Thomas and Yan’s models were fitted to the experimental data, being the latter the best fit.

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Plácido Castro‘s work has aroused our interest, because it evolves around the question of Galician personality and identity. While working as a journalist and a translator or while writing essays on different literary issues, Plácido Castro has never forgotten his roots or his nation. One could even say that his whole life turns around Galicia. Our purpose is to make a critical analysis of his work, especially as a translator, and try to show how he used translation in order to develop national conscience and identity and to see how far his ideology interfered in the interpretation and translation of Rossetti‘s poetry, in which he found a great similarity with Rosalìa de Castro‘s work.

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Agência Financiadora: Fundação para a Ciência e a Tecnologia/MCTES (Portugal) - PEst-OE/EQB/UI0702/2012