979 resultados para Palissy, Bernard, 1510?-1590.


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Few studies have addressed the relationship between law and power in the works of Michel Foucault. Some authors emphasize that law performs a completely secondary role in the diagram of power of modernity, while others argue that there is a close link between power relations and the law. Foucault's Law by Golden and Fitzpatrick aims to renew these discussions and reconstruct another law of Foucault. In this paper I make a critical reading of this work, highlighting the faulty presentation that the authors carried out of the works of Foucault.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We present time-series data on Jupiter Family Comets (JFCs) 17P/Holmes, 47P/Ashbrook-Jackson and 137P/Shoemaker-Levy 2. In addition we also present results from `snap-shot' observations of comets 43P/Wolf-Harrington, 44P/Reinmuth 2, 103P/Hartley 2 and 104P/Kowal 2 taken during the same run. The comets were at heliocentric distances of between 3 and 7 au at this time. We present measurements of size and activity levels for the snap-shot targets. The time-series data allow us to constrain rotation periods and shapes, and thus bulk densities. We also measure colour indices (V - R) and (R - I) and reliable radii for these comets. We compare all of our findings to date with similar results for other comets and Kuiper Belt Objects (KBOs). We find that the rotational properties of nuclei and KBOs are very similar, that there is evidence for a cut-off in bulk densities at ~0.6 g cm-3 in both populations, and the colours of the two populations show similar correlations. For JFCs, there is no observational evidence for the optical colours being dependent on either position in the orbit or orbital parameters.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The primary objective of this work is the analysis and interpretation of coronal observations of Capella obtained in 1999 September with the High Energy Transmission Grating Spectrometer on the Chandra X-ray Observatory and the Extreme Ultraviolet Explorer (EUVE). He-like lines of O (O vii) are used to derive a density of 1.7 x 10(10) cm(-3) for the coronae of the binary, consistent with the upper limits derived from Fe xxi, Ne ix and Mg xi line ratios. Previous estimates of the electron density based on Fe xxi should be considered as upper limits. We construct emission measure distributions and compare the theoretical and observed spectra to conclude that the coronal material has a temperature distribution that peaks around 4-6 MK, implying that the coronae of Capella were significantly cooler than in the previous years. In addition, we present an extended line list with over 100 features in the 5-24 Angstrom wavelength range, and find that the X-ray spectrum is very similar to that of a solar flare observed with SMM. The observed to theoretical Fe xvii 15.012-Angstrom line intensity reveals that opacity has no significant effect on the line flux. We derive an upper limit to the optical depth, which we combine with the electron density to derive an upper limit of 3000 km for the size of the Fe xvii emitting region. In the same context, we use the Si iv transition region lines of Capella from HST/Goddard High-Resolution Spectrometer observations to show that opacity can be significant at T = 10(5) K, and derive a path-length of approximate to 75 kin for the transition region. Both the coronal and transition region observations are consistent with very small emitting regions, which could be explained by small loops over the stellar surfaces.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Aquaporin-4 (AQP4) has recently been implicated in the pathogenesis of neuromyelitis optica(NMO) where it has been identifed as the first defined autoantigen pertinent to an infammatory demyelinating disorder of the human CNS. Furthermore, a recent case report has shown a lack of AQP4 expression in the spinal cord lesions of NMO. However, the pattern of AQP4 expression in multiple sclerosis (MS) tissues has not been well-defned. In the present investigation we have confirmed a lack of expression of AQP4 in optic and spinal cord lesions in NMO which contrasted sharply with the increased levels of AQP4 expression seen in MS lesions. Furthermore a detailed immunohistochemical and semi-quantitative analysis is used to describe the expression pattern of AQP4 on well-characterized tissue microarray samples of MS and control white matter. Anatomically AQP4 was more highly expressed in all categories of MS tissue compared to normal control tissues with the most abundant expression in active lesions. Within active lesions AQP4 expression was significantly correlated with expression of the pro-infammatory cytokine osteopontin. At the cellular level dual-labelling immunofluoresence demonstrated that increased expression of AQP4 was most pronounced at the astrocytic endfeet but was also associated with the cell bodies of astrocytes in the tissue parenchyma. The finding of increased AQP4 expression in MS lesions in contrast to the lack of expression in NMO lesions may suggest different mechanisms of initiation and progression between the two disease states.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A voluminous literature exists on the analysis of water-soluble ions extracted from gypsum crusts and patinas formed on building surfaces. However, less data is available on the intermediate dust layer and the important role its complex matrix and constituents play in crust/patina formation. To address this issue, surface dust samples were collected from two buildings in the city of Budapest. Substrate properties, different pollution levels and environmental variations were considered by collecting samples from a city centre granite building exposed to intense traffic conditions and from an oolitic limestone church situated in a pedestrian area outside and high above the main pollution zone. Selective extraction examines both water-soluble ions (Ca2+, Mg2+, Na+, K+, Cl-, NO3- SO42-) and selected elements (Fe, Mn, Zn, Cu, Cr, Pb, Ni) from the water-soluble, exchangeable/carbonate, amorphous Mn, amorphous Fe/Mn, crystalline Fe/Mn, organic and residual phases, their mobility and potential to catalyse heterogeneous surface reactions. Salt weathering processes are highlighted by high concentrations of water-soluble Ca2+, Na+, Cl- and SO42-- at both sites. Manganese, Zn and Cu and to a lesser extent Pb and Ni, are very mobile in the city centre dust, where 30%, 54%, 38%, 11% and 11% of their totals are bound by the water-soluble phase, respectively. Church dust shows a sharp contrast for Mn, Zn, Cu and Pb with only 3%, 1%, 12% and 3% of their totals being bound by the water-soluble phase respectively. This may be due to (a) different environmental conditions at the church e.g. lower humidity (b) continuous replenishment of salts under intensive city centre traffic conditions (c) enrichment in oxidisable organic carbon by a factor of 4.5 and a tenfold increase in acidity in the city centre dust.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Extensive contour scaling of a 200 year old granite church is associated with the breaching of an apparently iron-rich crust and the widespread deposition of atmospheric dust within the canyon-like streetscape of Rio de Janeiro. Contemporary dust, accumulated dust from within the a depression on the building surface, the surface crust and the underlying granite are examined by a combination of total element analysis and sequential extraction, X-ray diffraction and energy dispersive X-ray fluorescence. Results indicate an increase in total organic carbon and a marked decrease in pH within the accumulated dust, and a rapid mobilization of anions and cations from the water-soluble and carbonate phases. It is considered that the latter is linked to salt accumulation within and eventual salt weathering of the granite. Post-depositional alteration of the dust is also linked with the de-silicification of clay minerals (Illite to kaolinite) and the loss of silica from the amorphous Fe/Mn phase of the accumulated dust under the initially saline and progressively more acidic conditions experienced at the stone - atmosphere interface. This mobilization of silica is associated with the formation of what is, in effect, a thin silica-rich surface crust or glaze. Within the glaze, assessory amounts of extractable iron are concentrated within the amorphous and crystalline Fe/Mn phases at levels that are significantly elevated with respect to the underlying granite, but much lower than the equivalent phases of the accumulated dust from which it is principally assumed to derive. The protection afforded to the stone work by the crust is not, however, permanent and within the last 15 years it has been possible to observe a rapid increase in the surface delamination of the church close to street level.

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Los beneficios que aporta la musicoterapia en alumnos con Trastorno del Espectro Autista, han sido demostrados profusamente por los distintos autores, si bien carecemos de literatura suficiente sobre su utilización en las Aulas Abiertas Especializadas en colegios ordinarios (Aulas TEA). En este sentido, el objetivo del trabajo, ha consistido en analizar qué mejoras aporta la musicoterapia al desarrollo de la comunicación en los alumnos con Trastorno del Espectro Autista dentro de las Aulas Abiertas de los CEIPs de Castilla-La Mancha y la Comunidad Autónoma de Madrid. Para ello, se ha realizado una amplia revisión documental de fuentes de referencia y se ha entrevistado a los docentes responsables de las Aulas Abiertas Especializadas que utilizan actividades de musicoterapia como recurso en el aula. Se concluye el artículo manifestando, en primer lugar, la escasa integración de la musicoterapia en las aulas TEA (menos del 20% de los centros). En aquellas aulas que sí se programa con actividades de musicoterapia, los beneficios que ésta aporta se ven reflejados en un incremento claro de la intención comunicativa en los alumnos. Además, a la hora de planificar las actividades se tiene muy en cuenta conocer las preferencias y la historia musical del niño. No obstante, existen factores que impiden el aprovechamiento total de las posibilidades terapéuticas de la musicoterapia debido, especialmente a: a) una escasa formación del profesorado y b) un espacio inadecuado para poner en práctica una sesión de musicoterapia.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fire has long been recognized as an agent of rock weathering. Our understanding of the impact of fire on stone comes either from early anecdotal evidence, or from more recent laboratory simulation studies, using furnaces to simulate the effects of fire. This paper suggests that knowledge derived from simulated heating experiments is based on the preconceptions of the experiment designer – when using a furnace to simulate fire, the operator decides on the maximum temperature and the duration of the experiment. These are key factors in determining the response of the stone to fire, and if these are removed from realworld observations then knowledge based on these simulations must be questioned. To explore the differences between heating sandstone in a furnace and a real fire, sample blocks of Peakmoor Sandstone were subjected to different stress histories in combination (lime rendering and removal, furnace heating or fire, frost and salt weathering). Block response to furnace heating and fire is discussed, with emphasis placed on the non-uniformity of the fire and of block response to fire in contrast to the uniform response to surface heating in a furnace. Subsequent response to salt weathering (by a 10% solution of sodium chloride and magnesium sulphate) was then monitored by weight loss. Blocks that had experienced fire showed a more unpredictable response to salt weathering than those that had undergone furnace heating – spalling of corners and rapid catastrophic weight loss were evidenced in blocks that had been subjected to fire, after periods of relative quiescence. An important physical side-effect of the fire was soot accumulation, which created a waxy, relatively impermeable layer on some blocks. This layer repelled water and hindered salt ingress, but eventually detached when salt, able to enter the substrate through more permeable areas, concentrated and crystallized behind it, resulting in rapid weight loss and accelerated decay. Copyright ©2007 John Wiley & Sons, Ltd.