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Kurt Vanhoutte 《Foundations of Science》2013,18(1):149-153
As an art theoretician, and as a father, I focus on the social and political consequences of Vanderbeeken’s postmodernist negative theology. I express doubts about the relevance of a poetics of catastrophe that conflates any possible alternative to the alleged technocracy under the sign of the simulacrum. To my opinion, the discourse about the virtual and the real are in a deadlock. Following the lead of American novelist Thomas Pynchon, I rephrase these critical doubts in Luddite terms: should we imagine a counterattack as radical as the alleged dystopian nightmare dreamed up and sketched out by Vanderbeeken? I try to show that this line of thinking risks to result in a bold and speculative logic where ethical nuance collapses and, ultimately, the relationship between art, theory and the social culture is reduced to metaphorical analogy. To make this point I retake a critical, phenomenologically inspired reaction by Vivian Sobchack to Baudrillard’s account of Crash, J.G. Ballard’s controversial novel on techno-fetishism. My argument is that the scar that marks Sobchack’s ‘technobody’ might here stand for an alternative that approaches our technological condition not as a discursive machine but as a social pragmatics with deep ethical implications. 相似文献
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Kurt H. Meyer G. Noelting P. Bernfeld 《Cellular and molecular life sciences : CMLS》1947,3(9):370-371
Summary A colorimetric method based on the reducing power of the aldehydic end group has been developed in order to determine the M. W. of polysaccharides. It has been found that corn amylose contains chain molecules of much higher degree of polymerization than potato amylose. 相似文献
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Weitenberg C Endres M Sherson JF Cheneau M Schauss P Fukuhara T Bloch I Kuhr S 《Nature》2011,471(7338):319-324
Ultracold atoms in optical lattices provide a versatile tool with which to investigate fundamental properties of quantum many-body systems. In particular, the high degree of control of experimental parameters has allowed the study of many interesting phenomena, such as quantum phase transitions and quantum spin dynamics. Here we demonstrate how such control can be implemented at the most fundamental level of a single spin at a specific site of an optical lattice. Using a tightly focused laser beam together with a microwave field, we were able to flip the spin of individual atoms in a Mott insulator with sub-diffraction-limited resolution, well below the lattice spacing. The Mott insulator provided us with a large two-dimensional array of perfectly arranged atoms, in which we created arbitrary spin patterns by sequentially addressing selected lattice sites after freezing out the atom distribution. We directly monitored the tunnelling quantum dynamics of single atoms in the lattice prepared along a single line, and observed that our addressing scheme leaves the atoms in the motional ground state. The results should enable studies of entropy transport and the quantum dynamics of spin impurities, the implementation of novel cooling schemes, and the engineering of quantum many-body phases and various quantum information processing applications. 相似文献
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Sigmundsson F Hreinsdóttir S Hooper A Arnadóttir T Pedersen R Roberts MJ Oskarsson N Auriac A Decriem J Einarsson P Geirsson H Hensch M Ofeigsson BG Sturkell E Sveinbjörnsson H Feigl KL 《Nature》2010,468(7322):426-430
Gradual inflation of magma chambers often precedes eruptions at highly active volcanoes. During such eruptions, rapid deflation occurs as magma flows out and pressure is reduced. Less is known about the deformation style at moderately active volcanoes, such as Eyjafjallaj?kull, Iceland, where an explosive summit eruption of trachyandesite beginning on 14 April 2010 caused exceptional disruption to air traffic, closing airspace over much of Europe for days. This eruption was preceded by an effusive flank eruption of basalt from 20 March to 12 April 2010. The 2010 eruptions are the culmination of 18?years of intermittent volcanic unrest. Here we show that deformation associated with the eruptions was unusual because it did not relate to pressure changes within a single magma chamber. Deformation was rapid before the first eruption (>5?mm per day after 4 March), but negligible during it. Lack of distinct co-eruptive deflation indicates that the net volume of magma drained from shallow depth during this eruption was small; rather, magma flowed from considerable depth. Before the eruption, a ~0.05?km(3) magmatic intrusion grew over a period of three months, in a temporally and spatially complex manner, as revealed by GPS (Global Positioning System) geodetic measurements and interferometric analysis of satellite radar images. The second eruption occurred within the ice-capped caldera of the volcano, with explosivity amplified by magma-ice interaction. Gradual contraction of a source, distinct from the pre-eruptive inflation sources, is evident from geodetic data. Eyjafjallaj?kull's behaviour can be attributed to its off-rift setting with a 'cold' subsurface structure and limited magma at shallow depth, as may be typical for moderately active volcanoes. Clear signs of volcanic unrest signals over years to weeks may indicate reawakening of such volcanoes, whereas immediate short-term eruption precursors may be subtle and difficult to detect. 相似文献
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Perry L Sandweiss DH Piperno DR Rademaker K Malpass MA Umire A de la Vera P 《Nature》2006,440(7080):76-79
Over the past decade, increasing attention to the recovery and identification of plant microfossil remains from archaeological sites located in lowland South America has significantly increased knowledge of pre-Columbian plant domestication and crop plant dispersals in tropical forests and other regions. Along the Andean mountain chain, however, the chronology and trajectory of plant domestication are still poorly understood for both important indigenous staple crops such as the potato (Solanum sp.) and others exogenous to the region, for example, maize (Zea mays). Here we report the analyses of plant microremains from a late preceramic house (3,431 +/- 45 to 3,745 +/- 65 14C bp or approximately 3,600 to 4,000 calibrated years bp) in the highland southern Peruvian site of Waynuna. Our results extend the record of maize by at least a millennium in the southern Andes, show on-site processing of maize into flour, provide direct evidence for the deliberate movement of plant foods by humans from the tropical forest to the highlands, and confirm the potential of plant microfossil analysis in understanding ancient plant use and migration in this region. 相似文献
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