935 resultados para Historical evolution of the concept


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The sedimentary architecture of basins and passive margins is determined by a complex interaction of parameters, including subsidence, eustasy, and sediment supply. A quantification of the post-rift (20 Ma-0 Ma) vertical movements of the Gulf of Lion (West Mediterranean) is proposed here based on the stratigraphic study of sedimentary paleomarkers using a large 3D grid of reflection seismic data, correlations with existing drillings, and refraction data. Post-rift subsidence was measured by the direct use of sedimentary geometries analysed in 3D and validated by numerical stratigraphic modelling. Three domains of subsidence were found: on the continental shelf and slope, subsidence corresponds to a seaward tilting with different amplitudes, whereas the deep basin subsides purely vertically. We show that these domains fit with the deeper crustal domains highlighted by previous geophysical data, and that post-break-up subsidence follows the initial hinge lines of the rifting phase. Subsidence rates are quantified on each domain for each stratigraphic interval. At a constant distance from the rotational hinge line, the Plio-Quaternary subsidence rate is constant on the shelf overall. Conversely, Miocene subsidence rates are very different on the eastern and western shelves. Stratigraphic simulations focused on the Messinian salinity crisis (MSC) were also performed. Their results are discussed together with our post-rift subsidence estimates in order to provide ideas and hypotheses for future detailed quantifications of Miocene subsidence, including isostatic readjustments linked to the MSC.

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To study the stoichiometry dependence of irradiation e ects in fluorite-type mixed oxide nuclear fuel (UPuO2), ion implantation in La doped ceria was used. Cerium dioxide single crystals with 0 mol%, 5 mol% and 25 mol% La concentration were irradiated with 1 MeV Kr ions at 800 C. In-situ transmission electron microscope (TEM) was utilized to observe the the damage process and defects created by the ion beam irradiation. Dislocation loops were observed after irradiation and were determined to be on {111} planes, but not on {220} or {200} planes. Ab substantial difference in the average size of dislocation loops for 0 %, 5% and 25% cases was observed at several doses.The growth rate of dislocation loops and the oxygen vacancy di usivity were found to be inversely correlated.

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The relationship between the socio-economic status of parents and children is referred by the literature as intergenerational social mobility. The scope of this mobility encompasses different aspects such as educational attainment, income, wealth, prestige and occupational status. In particular, intergenerational occupational mobility is an interesting topic in the economic literature because it is positively associated with the economic achievement and the professional success. Low mobility implies that human capital, skills and talent can be misallocated. As a consequence, the workers’ efforts, their motivation and productivity could be negatively affected, which would have adverse effects on the economy growth and its competitiveness. This paper attempts to carry out the study of the evolution of intergenerational social mobility in Spain during the 21st century. The methodology applied involves to associate the National Classification of Occupations (CNO-94) with the New International Socio-economic Index of Occupational Status (ISEI-08), in order to establish a socio-economic hierarchy. Afterwards, once the occupational ranking is defined, we use statistic and econometric methods to assess the occupational transitions between fathers and children and to analyse the covariates’ effects on these transitions, including as explanatory variable the children’s educational attainment. Data used corresponds to the 2005 and 2011 Living Condition Survey (INE, 2005, 2011). The results of the study are displayed by distinguishing children according to their birth cohort.

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This article examines regulatory governance of the post-initial training market in The Netherlands. From an historical perspective on policy formation processes, it examines market formation in terms of social, economic, and cultural factors in the development of provision and demand for post-initial training; the roles of stakeholders in the longterm construction of regulatory governance of the market; regulation of and public providers; policy responses to market failure; and tripartite division of responsibilities between the state, social partners, commercial and publicly-funded providers. Historical description and analysis examine policy narratives of key stakeholders with reference to: a) influence of societal stakeholders on regulatory decision-making; b) state regulation of the post-initial training market; c) public intervention regulating the market to prevent market failure; d) market deregulation, competition, employability and individual responsibility; and, e) regulatory governance to prevent ‘allocative failure’ by the market in non-delivery of post-initial training to specific target groups, particularly the low-qualified. Dominant policy narratives have resulted in limited state regulation of the supply-side, a tripartite system of regulatory governance by the state, social partners and commercial providers as regulatory actors. Current policy discourses address interventions on the demand-side to redistribute structures of opportunity throughout the life courses of individuals. Further empirical research from a comparative historical perspective is required to deepen contemporary understandings of regulatory governance of markets and the commodification of adult learning in knowledge societies and information economies. (DIPF/Orig.)

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The fossiliferous deposits in the coastal plain of the Rio Grande do Sul State, Southern Brazil, have been known since the late XIX century; however, the biostratigraphic and chronostratigraphic context is still poorly understood. The present work describes the results of electron spin resonance (ESR) dating in eleven fossil teeth of three extinct taxa (Toxodon platensis, Stegomastodon waringi and Hippidion principale) collected along Chui Creek and nearshore continental shelf, in an attempt to assess more accurately the ages of the fossils and its deposits. This method is based upon the analysis of paramagnetic defects found in biominerals, produced by ionizing radiation emitted by radioactive elements present in the surrounding sediment and by cosmic rays. Three fossils from Chui Creek, collected from the same stratigraphic horizon, exhibit ages between (42 +/- 3) Ka and (34 +/- 7) Ka, using the Combination Uptake model for radioisotopes uptake, while a incisor of Toxodon platensis collected from a stratigraphic level below is much older. Fossils from the shelf have ages ranging from (7 +/- 1) 10(5) Ka to (18 +/- 3) Ka, indicating the mixing of fossils of different epochs. The origin of the submarine fossiliferous deposits seems to be the result of multiple reworking and redeposition cycles by sea-level changes caused by the glacial-interglacial cycles during the Quaternary. The ages indicate that the fossiliferous outcrops at Chui Creek are much younger than previously thought, and that the fossiliferous deposits from the continental shelf encompass Ensenadan to late Lujanian ages (middle to late Pleistocene). (C) 2009 Elsevier Ltd and INQUA. All rights reserved.

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A temporal study of energy transfer across length scales is performed in 3D numerical simulations of homogeneous shear flow and isotropic turbulence. The average time taken by perturbations in the energy flux to travel between scales is measured and shown to be additive. Our data suggests that the propagation of disturbances in the energy flux is independent of the forcing and that it defines a ‘velocity’ that determines the energy flux itself. These results support that the cascade is, on average, a scale-local process where energy is continuously transmitted from one scale to the next in order of decreasing size.

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The centriole and basal body (CBB) structure nucleates cilia and flagella, and is an essential component of the centrosome, underlying eukaryotic microtubule-based motility, cell division and polarity. In recent years, components of the CBB-assembly machinery have been identified, but little is known about their regulation and evolution. Given the diversity of cellular contexts encountered in eukaryotes, but the remarkable conservation of CBB morphology, we asked whether general mechanistic principles could explain CBB assembly. We analysed the distribution of each component of the human CBB-assembly machinery across eukaryotes as a strategy to generate testable hypotheses. We found an evolutionarily cohesive and ancestral module, which we term UNIMOD and is defined by three components (SAS6, SAS4/CPAP and BLD10/CEP135), that correlates with the occurrence of CBBs. Unexpectedly, other players (SAK/PLK4, SPD2/CEP192 and CP110) emerged in a taxon-specific manner. We report that gene duplication plays an important role in the evolution of CBB components and show that, in the case of BLD10/CEP135, this is a source of tissue specificity in CBB and flagella biogenesis. Moreover, we observe extreme protein divergence amongst CBB components and show experimentally that there is loss of cross-species complementation among SAK/PLK4 family members, suggesting species-specific adaptations in CBB assembly. We propose that the UNIMOD theory explains the conservation of CBB architecture and that taxon- and tissue-specific molecular innovations, gained through emergence, duplication and divergence, play important roles in coordinating CBB biogenesis and function in different cellular contexts.

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The flavonoids (including anthocyanins) are wine compounds with important anti-oxidant activity, protecting the cells against oxidative processes, preventing cardiovascular and neurodegenerative diseases, cancer, among others (Antoniolli et al. 2015; Castañeda-Ovando et al. 2009; Hosu et al. 2014; Huang et al. 2009; Kong et al. 2003). Anthocyanins in grapes at harvest are determinant to red wine quality and their development in the grape must be characterised in order to determine the most suitable date for the harvest. Thus the aim of this research is the evaluation of anthocyanins composition in two red wine grape varieties from véraison continuing through ripening. Anthocyanins were quantified by high resolution liquid chromatography (HPLC-DAD). Additionally, the total phenols content were quantified by UV-Vis Spectrometry. The anthocyanins’ profile evolution may be dependent on the variety and ripening phase. During ripening grape samples have shown an increase of coumaryl derivatives. This information may lead us to understand the anthocyanins biosynthesis pathway in different grape varieties. The development of anthocyanins from the véraison seems to follow a pattern that coincides with the increasing accumulation of soluble sugars.

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The stratigraphic record of the Early Carboniferous in Iberia reveals that synorogenic deposition was important and occurred simultaneously in basins influenced by extension and contraction with gravitational instability. In NW Iberia (Galicia – Trás-os-Montes Zone) contraction was dominant and the deposition took place in a forebulge outwards from the nappe stacking front. Here, synorogenic deposits were strongly affected by folding and thrusting as they were imbricated and incorporated in the allochthonous pile. In a different way, in SW Iberia (Ossa-Morena Zone) synorogenic deposition was influenced by extension and happened simultaneously with the onset of significant magmatism.

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Despite its increasing relevance, corporate social responsibility (CSR) remains hobbled by problems, variously charged as being chameleon, vacuous or an utterly meaningless concept. One reason is the absence of an agreed upon normative basis underpinning CSR. This is in large part due to the concept lacking a universally accepted definition. This paper explores how the concept of CSR has evolved over time drawing from 110 definitions of the construct. Using co-word analysis of definitions from 1953 to 2014, the study maps how the structure of the definitions has evolved during the field's historical development. The research uncovers the key terms underpinning the phenomenon, the centrality of these terms as well as mapping their interrelationships and evolution. The findings suggest that, despite the profusion and definitional heterogeneity over the six decades of the development of the field, there are six recurrent, enduring dimensions that underpin the CSR concept. These dimensions are economic, social, ethical, stakeholders, sustainability and voluntary. This paper makes several contributions to the academic literature. The systematic, quantitative analysis of definitions brings an objectivity that previous qualitative bibliometric analyses of CSR have lacked. The time period selected is substantially longer than previous analyses and captures the complete historical evolution of the concept. Moreover, the analysis provides the basis for the development of a new, comprehensive, yet concise, definition of CSR that captures all six of the recurring dimensions underpinning the concept.

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Pós-graduação em Matemática em Rede Nacional - IBILCE

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Este documento es un artículo inédito que ha sido aceptado para su publicación. Como un servicio a sus autores y lectores, Alternativas. Cuadernos de trabajo social proporciona online esta edición preliminar. El manuscrito puede sufrir alteraciones tras la edición y corrección de pruebas, antes de su publicación definitiva. Los posibles cambios no afectarán en ningún caso a la información contenida en esta hoja, ni a lo esencial del contenido del artículo.