996 resultados para Neutrinos Supernova Antarktis Eis Photonpropagation AMANDA Neutrinoteleskop Echtzeit
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This study uses an analytical model, based on the cooling-to-space approximation, and a fixed dynamical heating model to investigate the structure of the stratospheric cooling that occurs in response to a uniform increase in stratospheric water vapour (SWV). At all latitudes, the largest cooling occurs in the lower stratosphere and decreases in magnitude with height. The cooling is strongly enhanced in the Extratropics compared to the Tropics. This is markedly different to the case of an increase in CO2, which causes maximum cooling near the stratopause and a small warming in the tropical lower stratosphere. The qualitative differences in the structure of the cooling can be explained by the smaller opacity of water vapour bands in the stratosphere compared to CO2. The small opacity means that the magnitude of the initial heating rate perturbation only decreases by a factor of four between the upper and lower stratosphere for a SWV perturbation. Therefore, to balance the heating rate perturbation, the largest temperature change is required in the lower stratosphere. Increasing the background concentration of SWV causes the water vapour bands to become more opaque. For a SWV perturbation applied to a background SWV concentration ≥30 ppmv, the heating rate perturbation and temperature change structurally resemble those from an increase in CO2. In the Extratropics, the lower height of the tropopause is found to cause the enhancement in the cooling at those latitudes. By controlling the depth of atmosphere which adjusts to the SWV perturbation, the tropopause height affects the net exchange of radiation between the layers in the stratosphere as they cool. The latitudinal gradient in upwelling infrared radiation at the tropopause and variations in the background temperature are found to have only a minor effect on the structure of the stratospheric temperature response to a change in SWV.
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ABSTRACT: The Institute of Psychoplasmics is a group exhibition dealing with cults, rituals and the metaphor of the body politic. A key interest of the project is the way in which cultic groupings challenge the integrity of the social body by producing another within it. The exhibition, book and events explore parallels between the operations of new religious movements in the context of neo-liberalism and the forms of collectivity posited by contemporary art. These issues were addressed through a gallery display, academic essays, discussion, adult and children focused workshops and live performance event. The exhibition design, which considered the gallery as a research institute, itself investigated strategies of collaboration and psycho-social manipulation. The show was curated by Pil and Galia Kollectiv and commissioned by the Pump House Gallery in London and supported by Outset, Arts Council England and the Henry Moore Foundation. The exhibition included work by a.a.s., Insectoid, Diann Bauer, Amanda Beech, Mikko Canini, Seth Coston, Rod Dickinson, Pil and Galia Kollectiv, Tai Shani, Francis Upritchard and Roman Vasseur. A publication edited by the curators, features writing by Suhail Malik, Amanda Beech, Pil and Galia Kollectiv, Gilad Elbom, Tom McCarthy, Emily McMehen and Travis Jeppesen.
Resumo:
Modern Lovers was a survey show of contemporary art practices in dialogue with modernism, bringing together established and emerging artists based in London and international artists from Berlin, Jerusalem and Zagreb. The show features video, film, installation, sculpture, music and performance work that addresses the legacy of the avant garde and the survival of its aesthetics within contemporary culture. In 1976, as punk rock was busy smashing the cultural rubble left behind by the second world war and rejecting the consumer society that had emerged from the ruins, one band bravely announced that it wanted no part in this destruction. Jonathan Richman's Modern Lovers sang about how they still loved the old world. Neither parents nor girlfriends could understand, but the decaying inner city with its false promises of progress still held a fascination for Richman, who claimed he wanted to keep his place in this arcane landscape. Punk's assault on culture was the logical conclusion of modernism's linear narrative of art as a force of innovation that must reject preceding artistic movements to establish new ones. Echoing the negations of Dada, it set out to put an end to this narrative, an end to culture. It is partly because of this inherently destructive and totalising side of Modernism that it has come under harsh critique in the post modern era. Nevertheless, we are still caught up in the same dialectic of progress, revolution and destruction. Post modernism has failed to unseat our desire for the revolutionary moment, even as it has been co-opted to the degree of meaninglessness by the discourses of marketing and Capitalism. But, like Jonathan Richman, the artists in the exhibition "Modern Lovers" keep returning to modernism for something else. Instead of taking it at its word when it proffers revolution, they turn to it in search of reform. Still loving the old world and desiring a dialogue with the past, perhaps as an antidote to the eternal present of Capitalism, they are willing to engage with its aesthetics and ideas on equal ground. Leaving behind the ironic deconstructions of post modernism, they find perspectives worth salvaging and juxtapose them with contemporary visual productions. Trading in the grand narratives of modernity for a more personal approach, they don't seek the purity of form that drove the avant garde movements that inspire them but rather revel in adulteration, dilution and contamination of the past by the present". A live performance by sala-manca was sponsored by the British Council and took place May 26th, 19:00. MODERN LOVERS was accompanied by a catalogue (14.80 cm x 14.80 cm) including essays by Avi Pitchon, the sala-manca group and the curators. A discussion panel about the exhibition themes, as well as the catalogue launch,took place at Goldsmiths College's cinema on the 27th of May at 14:00, chaired by Dr. Suhail Malik (Senior Lecturer & Course Leader Postgraduate Fine Art Critical Studies at Goldsmiths College) and with the participation of Tom Morton (curator, Cubitt Gallery, and regular contributor to Frieze magazine), sala-manca (artist group), Dr. Amanda Beech (artist, curator and senior lecturer at the Wimbledon School of Art), Matthew Poole (course director of MA Gallery Studies, dept. of Art History and Theory at the University of Essex).
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Platelets play a vital role in maintaining haemostasis. Human platelet activation depends on Ca2+ release, leading to cell activation, granule secretion and aggregation. NAADP (nicotinic acid-adenine dinucleotide phosphate) is a Ca2+-releasing second messenger that acts on acidic Ca2+ stores and is used by a number of mammalian systems. In human platelets, NAADP has been shown to release Ca2+ in permeabilized human platelets and contribute to thrombin-mediated platelet activation. In the present study, we have further characterized NAADP-mediated Ca2+ release in human platelets in response to both thrombin and the GPVI (glycoprotein VI)-specific agonist CRP (collagen-related peptide). Using a radioligand-binding assay, we reveal an NAADP-binding site in human platelets, indicative of a platelet NAADP receptor. We also found that NAADP releases loaded 45Ca2+ from intracellular stores and that total platelet Ca2+ release is inhibited by the proton ionophore nigericin. Ned-19, a novel cell-permeant NAADP receptor antagonist, competes for the NAADP-binding site in platelets and can inhibit both thrombin- and CRP-induced Ca2+ release in human platelets. Ned-19 has an inhibitory effect on platelet aggregation, secretion and spreading. In addition, Ned-19 extends the clotting time in whole-blood samples. We conclude that NAADP plays an important role in human platelet function. Furthermore, the development of Ned-19 as an NAADP receptor antagonist provides a potential avenue for platelet-targeted therapy and the regulation of thrombosis.
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This article draws upon Karen Lury's definitions of 'space' and 'place' in relation to the BBC children's programme Blue Peter (1958–present). Through an analysis of the Blue Peter studio over the past 53 years, Amanda Beauchamp highlights its evolution from a 'space' to a 'place' within the history of children's television. Her article considers how the Blue Peter studio's 'infinite nature' was achieved, alongside the role it played in creating the programme institution. She addresses the impact of major changes in the studio layout since 2005, when the studio went from being 'tardis-like' to a 'cosy cubbyhole'. Amanda concludes by questioning the impact that this change has had on programme identity and whether the 'place' that pre-2005 Blue Peter took 47 years to create has been compromised.
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BACKGROUND: Bruchid beetles, Callosobruchus species, are serious pests of economically important grain legumes; their activity in stores is often controlled by use of synthetic insecticides. Esterases are known to be involved in insecticide resistance in insects. However, there is dearth of information on esterase activity in the genus Callosobruchus. In this study we investigated the effect of species, geographical strain and food type on the variation of acetylcholinesterase (AChE) activity and its inhibition by malaoxon (malathion metabolite) using an in vitro spectrophotometric method. RESULT: AChE activity varied significantly among species and strains and also among legume type used for rearing them. Generally irrespective of species, strain or food type, the higher the AChE activity of a population, the higher its inhibition by malaoxon. C. chinensis had the highest AChE activity of the species studied and in the presence of malaoxon it had the lowest remaining AChE activity, while C. rhodesianus retained the highest activity. CONCLUSION: A firsthand knowledge of AChE activity in regional Callosobruchus in line with the prevailing food types should be of utmost importance to grain legume breeders, researchers on plant materials for bruchid control and pesticide manufacturer/applicators for a robust integrated management of these bruchids.
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Red meat consumption causes a dose-dependent increase in fecal apparent total N-nitroso compounds (ATNC). The genotoxic effects of these ATNCs were investigated using two different Comet assay protocols to determine the genotoxicity of fecal water samples. Fecal water samples were obtained from two studies of a total of 21 individuals fed diets containing different amounts of red meat, protein, heme, and iron. The first protocol incubated the samples with HT-29 cells for 5 min at 4 degrees C, whereas the second protocol used a longer exposure time of 30 min and a higher incubation temperature of 37 degrees C. DNA strand breaks were quantified by the tail moment (DNA in the comet tail multiplied by the comet tail length). The results of the two Comet assay protocols were significantly correlated (r = 0.35, P = 0.003), however, only the second protocol resulted in detectable levels of DNA damage. Inter-individual effects were variable and there was no effect on fecal water genotoxicity by diet (P > 0.20), mean transit time (P = 0.588), or weight (P = 0.705). However, there was a highly significant effect of age (P = 0.019). There was no significant correlation between concentrations of ATNCs in fecal homogenates and fecal water genotoxicity (r = 0.04, P = 0.74). ATNC levels were lower in fecal water samples (272 microg/kg) compared to that of fecal homogenate samples (895 microg/kg) (P < 0.0001). Failure to find dietary effects on fecal water genotoxicity may therefore be attributed to individual variability and low levels of ATNCs in fecal water samples.
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The sonnet in English is usually located as a sixteenth-century innovation, firmly linked to Italian influences, and frequently associated with a distinctively modern consciousness. Yet the speed and comfort with which the form settled into English reflects the fact that the sonnet per se was preceded by a longstanding tradition of 14-line poems in English written in forms derived from French. Indeed, in terms of formal features, the earliest sonnets in English frequently fray into earlier forms, sharing more with the roundel than with later sonnets. This article considers a number of features of style and content that various writers on the sonnet have argued to be characteristic, sometimes definitive, of the sonnet. These features include repetition, formal unity/division of octave and sestet, use of the volta, asymmetry, argument and development, and a preoccupation with contradictions and the self. The article shows that, while it is true that these features are characteristic of many sonnets, they are not peculiarly characteristic of sonnets, and they can all be found in earlier 14-line poems. Furthermore, a number of the earliest sonnets in English do not themselves possess these ‘sonnet-like’ characteristics. The otherness and the modernity of the sonnet have thus been overstated.
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This article discusses the literary relationship of the novelist and memoirist,Anne Thackeray Ritchie (1837–1919), and her step-niece, Virginia Woolf.Ritchie’s influence was a highly significant one which prompted a powerful ambiguity in Woolf, who was alternately admiring and dismissively anxious to deny influence, eager to relegate her to a staunchly Victorian past while covertly sensitive to those elements in her writing linking her with Modernism. These ‘Modern’ elements, including emphasis on the subjective nature of reality and the everyday life of the mind, occur in Ritchie’s fiction, affecting its style and structure. This article focuses on Night and Day, then on Woolf ’s more direct comments about Ritchie in diaries, letters and essays, comparing these comments and Woolf ’s theoretical agenda in defining Modernism and, implicitly, her own place in it. It also considers some of Ritchie’s fiction, with particular attention to two novellas, one a source for To The Lighthouse.