7,427 research outputs found

    The Spirit and The Word

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    https://digitalcommons.acu.edu/crs_books/1037/thumbnail.jp

    High fidelity sorting of remarkably similar components via metal-mediated assembly.

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    Subtle differences in ligand coordination angle and rigidity lead to high fidelity sorting between individual components displaying identical coordination motifs upon metal-mediated self-assembly. Narcissistic self-sorting can be achieved between highly similar ligands that vary minimally in rigidity and internal coordination angle upon combination with Fe(ii) ions and 2-formylpyridine. Selective, sequential cage formation can be precisely controlled in a single flask from a mix of three different core ligands (and 33 total components) differing only in the hybridization of one group that is uninvolved in the metal coordination process

    Occupy: 'struggles for the common or an 'anti-politics of dignity? Reflections on Hardt and Negri and John Holloway

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    This article provides a critical examination of Michael Hardt and Antonio Negri’s and John Holloway’s theory of revolutionary subjectivity, and does so by applying their theories to the Occupy movement of 2011. Its central argument is that one should avoid collapsing ‘autonomist’ and ‘open’ Marxism, for whilst both approaches share Tronti’s (1979) insistence on the constituent role of class struggle, and also share an emphasis on a prefigurative politics which engages a non-hierarchical and highly participatory politics, there nevertheless remain some significant differences between their approaches. Ultimately, when applied to Occupy Movement whilst their theory isn’t entirely unproblematic, I will argue that Hardt and Negri’s ‘autonomist’ approach offers the stronger interpretation, due mainly to their revised historical materialism

    Visions of Automation and Realities of Certification

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    Quite a lot of people envision automation as the solution to many of the problems in aviation and air transportation today, across all sectors: commercial, private, and military. This paper explains why some recent experiences with complex, highly-integrated, automated systems suggest that this vision will not be realized unless significant progress is made over the current state-of-the-practice in software system development and certification

    The Lore of Low Methane Livestock:Co-Producing Technology and Animals for Reduced Climate Change Impact

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    Methane emissions from sheep and cattle production have gained increasing profile in the context of climate change. Policy and scientific research communities have suggested a number of technological approaches to mitigate these emissions. This paper uses the concept of co-production as an analytical framework to understand farmers’ evaluation of a 'good animal’. It examines how technology and sheep and beef cattle are co-produced in the context of concerns about the climate change impact of methane. Drawing on 42 semi-structured interviews, this paper demonstrates that methane emissions are viewed as a natural and integral part of sheep and beef cattle by farmers, rather than as a pollutant. Sheep and beef cattle farmers in the UK are found to be an extremely heterogeneous group that need to be understood in their specific social, environmental and consumer contexts. Some are more amenable to appropriating methane reducing measures than others, but largely because animals are already co-constructed from the natural and the technical for reasons of increased production efficiency

    Magnetospheric Eclipses in the Binary Pulsar J0737-3039

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    (Abridged) In the binary radio pulsar system J0737-3039, the faster pulsar A is eclipsed once per orbit. We construct a simple geometric model which successfully reproduces the eclipse light curves, based on the idea that the radio pulses are attenuated by synchrotron absorption on the closed magnetic field lines of pulsar B. The model explains most of the properties of the eclipse: its asymmetric form, the nearly frequency-independent duration, and the modulation of the brightness of pulsar A at both once and twice the rotation frequency of pulsar B in different parts of the eclipse. This detailed agreement confirms the dipolar structure of the star's poloidal magnetic field. The model makes clear predictions for the degree of linear polarization of the transmitted radiation. The weak frequency dependence of the eclipse duration implies that the absorbing plasma is relativistic, with a density much larger than the corotation charge density. Such hot, dense plasma can be effectively stored in the outer magnetosphere, where cyclotron cooling is slow. The gradual loss of particles inward through the cooling radius is compensated by an upward flux driven by a fluctuating component of the current, and by the pumping of magnetic helicity on the closed field lines. The trapped particles are heated to relativistic energies by the damping of magnetospheric turbulence and, at a slower rate, by the absorption of the radio emission of the companion pulsar.Comment: 45 pages, 13 figures, submitted to ApJ; minor typo correcte
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