943 resultados para Formation of the theoretical conceptions


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We discuss the distributions and transports of the main water masses in the North Atlantic Subpolar Gyre (NASPG) for the mean of the period 2002–2010 (OVIDE sections 2002–2010 every other year), as well as the inter-annual variability of the water mass structure from 1997 (4x and METEOR sections) to 2010. The water mass structure of the NASPG, quantitatively assessed by means of an Optimum MultiParameter analysis (with 14 water masses), was combined with the velocity fields resulting from previous studies using inverse models to obtain the water mass volume transports. We also evaluate the relative contribution to the Atlantic Meridional Overturning Circulation (AMOC) of the main water masses characterizing the NASPG, identifying the water masses that contribute to the AMOC variability. The reduction of the magnitude of the upper limb of the AMOC between 1997 and the 2000s is associated with the reduction in the northward transport of the Central Waters. This reduction of the northward flow of the AMOC is partially compensated by the reduction of the southward flow of the lower limb of the AMOC, associated with the decrease in the transports of Polar Intermediate Water and Subpolar Mode Water (SPMW) in the Irminger Basin. We also decompose the flow over the Reykjanes Ridge from the East North Atlantic Basin to the Irminger Basin (9.4 ± 4.7 Sv) into the contributions of the Central Waters (2.1 ± 1.8 Sv), Labrador Sea Water (LSW, 2.4 ± 2.0 Sv), Subarctic Intermediate Water (SAIW, 4.0 ± 0.5 Sv) and Iceland–Scotland Overflow Water (ISOW, 0.9 ± 0.9 Sv). Once LSW and ISOW cross over the Reykjanes Ridge, favoured by the strong mixing around it, they leave the Irminger Basin through the deep-to-bottom levels. The results also give insights into the water mass transformations within the NASPG, such as the contribution of the Central Waters and SAIW to the formation of the different varieties of SPMW due to air–sea interaction.

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Fold-and-thrust belts are prominent structures that occur at the front of compressional orogens. To unravel the tectonic and metamorphic evolution of such complexes, kinematic investigations, quantitative microstructural analysis and geothermometry (calcite–graphite, calcite–dolomite) were performed on carbonate mylonites from thrust faults of the Helvetic nappe stack in Central Switzerland. Paleo-isotherms of peak temperature conditions and cooling stages (fission track) of the nappe pile were reconstructed in a vertical section and linked with the microstructural and kinematic evolution. Mylonitic microstructures suggest that under metamorphic conditions close to peak temperature, strain was highly localized within thrust faults where deformation temperatures spatially continuously increased in both directions, from N to S within each nappe and from top–down in the nappe stack, covering a temperature range of 180–380 °C. Due to the higher metamorphic conditions, thrusting of the lowermost nappe, the Doldenhorn nappe, was accompanied by a much more pronounced nappe internal ductile deformation of carbonaceous rock types than was the case for the overlying Wildhorn- and Gellihorn nappes. Ongoing thrusting brought the Doldenhorn nappe closer to the surface. The associated cooling resulted in a freezing in of the paleo-isotherms of peak metamorphic conditions. Contemporaneous shearing localized in the basal thrust, initially still in the ductile deformation regime and finally as brittle faulting and cataclasis inducing ultimately an inverse metamorphic zonation. With ongoing exhumation and the formation of the Helvetic antiformal nappe stack, a bending of large-scale tectonic structures (thrusts, folds), peak temperature isotherms and cooling isotherms occurred. While this local bending can directly be attributed to active deformation underneath the section investigated up to times of 2–3 ma, a more homogeneous uplift of the entire region is suggested for the very late and still active exhumation stage.

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The photochemistry and photophysics of 4-chlorophenol (4-CP) were studied onto two model solid supports, silicalite and beta-cyclodextrin (beta-Cl)), using time resolved diffuse reflectance techniques and product degradation analysis. The results have shown that the photochemistry and photophysics of 4-CP are different from solution and depend on the solid. Ground state diffuse reflectance and time resolved luminescence demonstrated the inclusion of the probe in both substrates. 4-CP exhibits room temperature luminescence in both hosts, being structured and much more intense in beta-CD. The emission was assigned to phosphorescence of the inclusion complex. Transient absorption demonstrated the formation of the unsubstituted phenoxyl radical and of 4-chlorophenoxyl radical in beta-CD. In silicalite only the later was detected. The studies of the photodegradation products indicate that phenol is the main photoproduct in beta-CD. In silicalite the chromatographic analysis indicates the presence of products that involve the ring cleavage. (C) 2002 Elsevier Science B.V. All rights reserved.

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The Scottish Legendary is a fourteenth century collection of saints’ lives in Older Scots. The prologue describes the lives as ‘merroure’ (mirror) to readers from which ‘men ma ensample ta’ (people may take example). Thus, the Legendary sets out to reveal how the reader is (mirror) thereby moving her to wish to become how she should be (exemplarity). This dissertation argues that, rather than encouraging devotion to saints along purely dogmatic lines, the Legendary transforms the reader’s selfhood by engaging her affectively, i.e. on an emotional and somatic level. By provoking the reader affectively, the text puts the reader into what Julia Kristeva has described as a ‘semiotic state’ which harks back to the reader’s or listener’s pre-cultural, pre-subjective self (Kristeva, 1984). Thus, the text disrupts the reader’s conception of herself as a complete, hermetic subjectivity, thereby dissolving the boundaries of the reader’s self. The Legendary most powerfully infiltrates the reader’s sense of self along these lines in the moments in which female saints’ bodies are tortured and dismembered. These scenes foreground the permeability of human flesh as well as its powerful influence over selfhood. Such images of abjection are, in Kristeva’s words, ‘opposed to I’; by confronting the reader with the disintegration of subjectivity in abjection, the text incites the reader to likewise experience herself as abject, i.e. disintegrable and permeable (Kristeva 1982). As I shall demonstrate, Kristeva’s psychoanalytic theory of the formation of the self offers a fruitful framework for understanding the processes of self-knowledge through reading that these saints’ lives inspire.

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Pós-graduação em Educação - FFC

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We study here the reactions between C-60 and planar C5H5+ cations that lead to the formation of [C60C5H5](+) adduct cations in the chemical ionization source of the mass spectrometer. The structures, stabilities and charge locations of some possible isomers of [C60C5H5](+): sigma-adduct, pi-complex, [1,4]- and [1,2]-addition cations, are studied by AM1 semiempirical molecular orbital calculations. We find that the most stable is the sigma-addition cation. Another interesting and stable structure is the pi-complex cation which is bonded by the electrostatic interaction at the inter-ring distance of 1.589 Angstrom with the C-5v symmetry. The C5H5+ cyclopentadienium cation seems to be an ''inverted umbrella'' sitting on a five-membered ring of the C-60 cage.

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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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Biotic and abiotic emissions of molecular iodine and iodocarbons from the sea or the ice surface and the intertidal zone to the coastal/polar marine boundary layer lead to the formation of iodine oxides, which subsequently nucleate forming iodine oxide particles (IOPs). Although the link between coastal iodine emissions and ultrafine aerosol bursts is well established, the details of the nucleation mechanism have not yet been elucidated. In this paper, results of a theoretical study of a range of potentially relevant aggregation reactions of different iodine oxides, as well as complexation with water molecules, are reported. Thermochemical properties of these reactions are obtained from high level ab initio correlated calculations including spin–orbit corrections. The results show that the nucleation path most likely proceeds through dimerisation of I2O4. It is also shown that water can hinder gas-to-particle conversion to some extent, although complexation with key iodine oxides does not remove enough of these to stop IOP formation. A consistent picture of this process emerges from the theoretical study presented here and the findings of a new laboratory study reported in the accompanying paper (Gomez Martin et al., 2013).

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In this contribution, results of a theoretical study on different reactions that odine oxides, in the presence of water, can undergo to form iodine oxides particles in the atmosphere. Thermodynamic and kinetic properties of these reactions have been obtained at high level ab initio correlated calculations.

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The workplace is evolving and the predicted impact of demographic changes (Salt, 2009; Taylor, 2005) has seen organisations focus on strategic workforce planning. As part of this, many organisations have established or expanded formalised graduate programs to attract graduates and transition them effectively into organisations (McDermott, Mangan, & O'Connor, 2005; Terjesen, Freeman, & Vinnicombe, 2007). The workplace context is also argued to be changing because of the divergence in preferences and priorities across the different generations in the workplace - a topic which is prolific in the popular culture media but is yet to be fully developed in the academic literature (Jorgenson, 2003). The public sector recruits large numbers of graduates and maintains well established graduate programs. Like the workplace context, the public sector is seen to be undergoing a transition to more closely align its practices and processes with that of the private sector (Haynes & Melville Jones, 1999; N. Preston, 1995). Consequently, questions have been raised as to how new workforce entrants see the public sector and its associated attractiveness as an employment option. This research draws together these issues and reviews the formation of, and change in, the psychological contracts of graduates across ten Queensland public sector graduate programs. To understand the employment relationship, the theories of psychological contract and public service motivation are utilised. Specifically, this research focuses on graduates' and managers' expectations over time, the organisational perspective of the employment relationship and how ideology influences graduates' psychological contract. A longitudinal mixed method design, involving individual interviews and surveys, is employed along with significant researcher-practitioner collaboration throughout the research process. A number of important qualitative and quantitative findings arose from this study and there was strong triangulation between results from the two methods. Prior to starting with the organisation, graduates found it difficult to articulate their expectations; however, organisational experience rapidly brought these to the fore. Of the expectations that became salient, most centred on their relationship with their supervisor. Without experience and quality information on which to base their expectations, graduates tended to over-rely on sectoral stereotypes which negatively impacted their psychological contracts. Socialisation only limited affected graduates' psychological contracts and public service motivation. The graduate survey, measured thrice throughout the first 12 months of the graduate program, revealed that the psychological contract and public service motivation results followed a similar trajectory of beginning at mediocre levels, declining between times one and two and increasing between times two and three (although this is not back to original levels). Graduates attributed these to a number of sectoral, organisational, team, supervisory and individual factors. On a theoretical level, this research provides support for the notion of ideology within the psychological contract although it raises some important questions about how it is conceptualised. Additionally, support is given for the manager to be seen as the primary organisational counterpart to the employee in future theoretical and practical work. The research also argues to extend current notions of time within the psychological contract as this seems to be the most divergent and combustible issue across the generations in terms of how the workplace is perceived. A number of practical implications also transpire from the study and the collaborative foundation was highly successful. It is anticipated that this research will make a meaningful contribution to both the theory and practice of the employment relationship with particular regard to graduates entering the public sector.

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In this paper, two ideal formation models of serrated chips, the symmetric formation model and the unilateral right-angle formation model, have been established for the first time. Based on the ideal models and related adiabatic shear theory of serrated chip formation, the theoretical relationship among average tooth pitch, average tooth height and chip thickness are obtained. Further, the theoretical relation of the passivation coefficient of chip's sawtooth and the chip thickness compression ratio is deduced as well. The comparison between these theoretical prediction curves and experimental data shows good agreement, which well validates the robustness of the ideal chip formation models and the correctness of the theoretical deducing analysis. The proposed ideal models may have provided a simple but effective theoretical basis for succeeding research on serrated chip morphology. Finally, the influences of most principal cutting factors on serrated chip formation are discussed on the basis of a series of finite element simulation results for practical advices of controlling serrated chips in engineering application.