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Walker G.,University of Oxford | Walker G.,Keble College
Geography Compass | Year: 2014

The political economy of urban water management demands the interrogation of a highly socialised and engineered space. Many approaches are available to the researcher, yet they are often based on their own claims concerning the nature of society and space, which are contradictory and incommensurate with the next. This makes a synthesis of theory problematic, suggesting an 'either/or' decision to the researcher. This paper provides a critical genealogy of theoretical approaches to the political economy of urban water management and a framework through which their synthesis may be discussed. It employs a critical realist philosophy, mapping each approach to its respective ontological and epistemic grounding. A metaphorical 'walk' is then taken across the resulting map in order to provide a coherent and logical survey of theory. Finally, critical realism is employed to argue that struggles to synthesise theory are rooted in their competing ontological claims. Critical realism and in particular Bob Jessop's Strategic Relational Approach are assessed as means of reconciling tensions uncovered during the walk. © 2014 John Wiley & Sons Ltd.

Nikitenko L.L.,University College London | Nikitenko L.L.,Keble College | Nikitenko L.L.,Linacre College | Shimosawa T.,University of Tokyo | And 8 more authors.
Journal of Investigative Dermatology | Year: 2013

Secondary lymphedema is a debilitating condition, and genetic factors predisposing to its development remain largely unknown. Adrenomedullin (AM) is peptide encoded, together with proadrenomedullin N-terminal peptide (PAMP), by the Adm gene (adrenomedullin gene). AM and its putative receptor calcitonin receptor-like receptor (CLR) are implicated in angiogenesis and lymphangiogenesis during embryogenesis and wound healing, suggesting their possible involvement in secondary lymphedema. To investigate whether AM deficiency predisposes to secondary lymphedema, we used heterozygous adult mice with Adm gene-knockin stop mutation, which selectively abrogated AM, but preserved PAMP, expression (Adm AM+/Δ animals). After hind limb skin incision, Adm messenger RNA expression was upregulated in wounded tissue of both Adm AM+/+ and Adm AM+/Δ mice. However, only Adm AM+/Δ animals developed limb swelling and histopathological lymphedematous changes, including epidermal thickening, elevated collagen fiber density, and increased microvessel diameter. Secondary lymphedema was prevented when circulating AM levels in Adm AM+/Δ mice were restored by systemic peptide delivery. In human skin, CLR was expressed in tissue components affected by lymphedema, including epidermis, lymphatics, and blood vessels. Our study identified a previously unrecognized role for endogenous AM as a key factor in secondary lymphedema pathogenesis and provided experimental in vivo evidence of an underlying germ-line genetic predisposition to developing this disorder. © 2013 The Society for Investigative Dermatology.

Wood R.E.,Australian National University | Wood R.E.,University of Oxford | Arrizabalaga A.,University of the Basque Country | Camps M.,University of Maryland University College | And 11 more authors.
Journal of Human Evolution | Year: 2014

Since the late 1980s, northern Iberia has yielded some of the earliest radiocarbon dated Aurignacian assemblages in Western Europe, probably produced by anatomically modern humans (AMHs). This is at odds with its location furthest from the likely eastern entry point of AMHs, and has also suggested to some that the Châtelperronian resulted from cultural transfer from AMHs to Neanderthals. However, the accuracy of the early chronology has been extensively disputed, primarily because of the poor association between the dated samples and human activity. Here, we test the chronology of three sites in northern Iberia, L'Arbreda, Labeko Koba and La Viña, by radiocarbon dating ultrafiltered collagen from anthropogenically modified bones. The published dates from Labeko Koba are shown to be significant underestimates due to the insufficient removal of young contaminants. The early (c.44 ka cal BP [thousands of calibrated years before present]) Aurignacian chronology at L'Arbreda cannot be reproduced, but the reason for this is difficult to ascertain. The existing chronology of La Viña is found to be approximately correct. Together, the evidence suggests that major changes in technocomplexes occurred contemporaneously between the Mediterranean and Atlantic regions of northern Iberia, with the Aurignacian appearing around 42 ka cal BP, a date broadly consistent with the appearance of this industry elsewhere in Western Europe. © 2014 Elsevier Ltd.

Pope J.E.,University of Oxford | Kay A.,Royal Holloway, University of London | Kay A.,Keble College
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

The assumption of free will - the ability of an experimentalist to make random choices - is central to proving the indeterminism of quantum resources, the primary tool in quantum cryptography. Relaxing the assumption in a Bell test allows violation of the usual classical threshold by correlating the random number generators used to select measurements with the devices that perform them. In this paper, we examine not only these correlations, but those across multiple runs of the experiment. This enables an explicit exposition of the optimal cheating strategy and how the correlations manifest themselves within this strategy. Similar to other recent results, we prove that there remain Bell violations for a sufficiently high, yet nonmaximal degree of free will which cannot be simulated by a classical attack, regardless of how many runs of the experiment those choices are correlated over. © 2013 American Physical Society.

Kay A.,National University of Singapore | Kay A.,Keble College
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

Perfect transfer of a quantum state through a one-dimensional chain is now well understood, allowing one not only to decide whether a fixed Hamiltonian achieves perfect transfer but to design a suitable one. We are particularly interested in being able to design, or understand the limitations imposed upon, Hamiltonians subject to various naturally arising constraints such as a limited coupling topology with low connectivity (specified by a graph) and type of interaction. In this paper, we characterize the necessary and sufficient conditions for transfer through a network and describe some natural consequences such as the impossibility of routing between many different recipients for a large class of Hamiltonians and the limitations on transfer rate. We also consider some of the trade-offs that arise in uniformly coupled networks (both Heisenberg and XX models) between transfer distance and the size of the network as a consequence of the derived conditions. © 2011 American Physical Society.

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