27 resultados para rupture de masse
Resumo:
La recherche sur le religieux en Afrique s’est beaucoup intéressée, ces vingt dernières années, au phénomène du « renouveau religieux », et elle s’est plutôt penchée sur la question des ruptures et des innovations qui en résultent. Le présent article interroge la réalité ce renouveau et explore, sur la base d’une étude de cas, la question des continuités et des ruptures dans les changements survenus [1]. Tout d’abord, il s’intéresse à la nature du renouveau religieux au Mozambique ; il examine ensuite les continuités historiques et dénominationnelles existantes au sein du renouveau pour discuter, dans une troisième section, l’impact des transformations religieuses sur la relation entre religion et politique. La conclusion tente, elle, de faire la part entre ruptures et permanences, et d’appréhender la question du renouveau au-delà de cette dichotomie.
Resumo:
Sedimentological and accelerator mass spectrometry (AMS) 14C data provide estimates of the structure and age of five submarine landslides (∼0.4–3 km3) present on eastern Australia's continental slope between Noosa Heads and Yamba. Dating of the post-slide conformably deposited sediment indicates sediment accumulation rates between 0.017 m ka–1 and 0.2 m ka–1, which is consistent with previous estimates reported for this area. Boundary surfaces were identified in five continental slope cores at depths of 0.8 to 2.2 m below the present-day seafloor. Boundary surfaces present as a sharp colour-change across the surface, discernible but small increases in sediment stiffness, a slight increase in sediment bulk density of 0.1 g cm–3, and distinct gaps in AMS 14C ages of at least 25 ka. Boundary surfaces are interpreted to represent a slide plane detachment surface but are not necessarily the only ones or even the major ones. Sub-bottom profiler records indicate that: (1) the youngest identifiable sediment reflectors upslope from three submarine landslides terminate on and are truncated by slide rupture surfaces; (2) there is no obvious evidence for a post-slide sediment layer draped over, or burying, slide ruptures or exposed slide detachment surfaces; and (3) the boundary surfaces identified within the cores are unlikely to be near-surface slide surfaces within an overall larger en masse dislocation. These findings suggest that these submarine landslides are geologically recent (<25 ka), and that the boundary surfaces are either: (a) an erosional features that developed after the landslide, in which case the boundary surface age provides a minimum age for the landslide; or (b) detachment surfaces from which slabs of near-surface sediment were removed during landsliding, in which case the age of the sediment above the boundary surface indicates the approximate age of landsliding. While an earthquake-triggering mechanism is favoured for the initiation of submarine landslides on the eastern Australian margin, further evidence is required to confirm this interpretation.
Resumo:
Recent experiments suggest that gold single-atom contacts and atomic chains break at applied voltages of 1 to 2 V. In order to understand why current flow affects these defect-free conductors, we have calculated the current-induced forces on atoms in a Au chain between two Au electrodes. These forces are not by themselves sufficient to rupture the chain. However, the current reduces the work to break the chain, which results in a dramatic increase in the probability of thermally activated spontaneous fracture of the chain. This current-induced embrittlement poses a fundamental limit to the current-carrying capacity of atomic wires.
Resumo:
After the twelve-year rupture caused by the Nazis, in the Soviet zone after 1945 attempts were made to reconnect with the traditions of workers’ songs and critical folk songs that were viewed as the cultural heritage of the communist movement. One of these ‘repertoires’ of song was that of the 1848 Revolution. In the 1950s GDR researchers such as the Germanist Bruno Kaiser, the musicologist Inge Lammel and in particular the folklorist Wolfgang Steinitz made substantial contributions to the collecting and publication of the 1848 songs. Their work provided an important reference point for the singers of the German folk song revival in the GDR from the late 1970s onwards. As the cases of groups such as Folkländer and Wacholder showed, theirs was a particularly creative appropriation of the revolutionary Erbe that involved performing protest songs of the past as if they were criticising the present.
Resumo:
Systematic reviews of systematic reviews identify good quality reviews of earlier studies of medical conditions. This article describes a systematic review of systematic reviews performed to investigate factors that might influence the risk of rupture of an intracranial aneurysm. It exemplifies the technique of this type of research and reports the finding of a specific study. The annual incidence of subarachnoid haemorrhage resulting from the rupture of intracranial aneurysms is estimated to be nine per 100,000. A large proportion of people who have this bleed, will die or remain dependent on the care of others for some time. Reliable knowledge about the risks of subarachnoid haemorrhage in different populations will help in planning, screening and prevention strategies and in predicting the prognosis of individual patients. If the necessary data were available in the identified reviews, an estimate for the numerical relationship between a particular characteristic and the risk of subarachnoid haemorrhage was included in this report. The identification of eligible systematic reviews relied mainly on the two major bibliographic databases of the biomedical literature: PubMed and EMBASE. These were searched in 2006, using specially designed search strategies. Approximately 2,000 records were retrieved and each of these was checked carefully against the eligibility criteria for this systematic review. These criteria required that the report be a systematic review of studies assessing the risk of subarachnoid haemorrhage in patients known to have an unruptured intracranial aneurysm or of studies that had investigated the characteristics of people who experienced a subarachnoid haemorrhage without previously being known to have an unruptured aneurysm. Reports which included more than one systematic review were eligible and each of these reviews was potentially eligible. The quality of each systematic review was assessed. In this review, 16 separate reports were identified, including a total of 46 eligible systematic reviews. These brought together research studies for 24 different risk factors. This has shown that the following factors appear to be associated with a higher risk of subarachnoid haemorrhage: being a woman, older age, posterior circulation aneurysms, larger aneurysms, previous symptoms,
Resumo:
The microstructure evolution of a 10Cr ferritic/martensitic heat-resistant steel during creep at 600°C was investigated in this work. Creep tests demonstrated that the 10Cr steel had higher creep strength than conventional ASME-P92 steel at 600°C. The microstructure after creep was studied by transmission electron microscopy, scanning electron microscopy and electron probe microanalysis. It was revealed that the martensitic laths were coarsened with time and eventually developed into subgrains after 8354 h. Laves phase was observed to grow and cluster along the prior austenite grain boundaries during creep and caused the fluctuation of solution and precipitation strengthening effects, which was responsible for the two slope changes on the creep rupture strength vs rupture time curve. It was also revealed that the microstructure evolution could be accelerated by stress, which resulted in the lower hardness in the deformed part of the creep specimen, compared with the aging part.
Resumo:
This article with the conception of space in Paul Celan's poetics, comparing it to Martin Buber's and developing a notion of 'realisation', important to both Celan and Buber. Partant du concept du fantastique en tant qu'espace dans laquelle les phénomènes sont véritablement perçus au lieu de simplement se dérouler, l'article montre comment la rupture avec la réalité accoutumée peut mener à une sensation intense de l'être. Chez Martin Buber se trouve la description d'un telle espace, où l'unité est créée à partir de la polarité de tout ce qui est. Le poème peut représenter un exemple d'un tel espace « réalisant ». La conception de l'espace chez Buber est démontrée en dialogue avec le poème STEHEN de Paul Celan, afin de montrer comment le monde réifié est « réalisé » par la poésie. Ainsi sont mis en valeur le rapport mutuel et le lien indispensable entre réalités sociales et la réalité du non-espace.