2,248 research outputs found

    Producing & Consuming Public Space: A ‘Rhythmanalysis’ of the Urban Park

    Get PDF
    Research suggests an opportunity to offer a more comprehensive analysis of temporal consumption experiences encountered by park users, and the subsequent contribution to a perceived ‘sense of place’. Using visual ethnography and rhythmanalysis, our study distances our analysis from textual accounts of park usage as well as provide policy recommendations

    A kaleidoscopic view of the territorialized consumption of place

    Get PDF
    Drawing on Brighenti’s (2010, 2014) theoretical exposition of territorology, we extend current conceptualisations of place within the marketing literature by demonstrating that place is relationally constructed through territorialising consumption practices which continuously produce and sustain multifarious versions of place. In our fieldwork, we embrace a non-representational sensitivity and employ a multi-sensory ethnography, thus helping to illuminate the performative aspects of everyday life relating to people who use urban green spaces. Our analysis articulates three key facets relating to the process of territorialising consumption practices: (1) Tangible and intangible elements of boundary-making; (2) Synchronicity of activities; and (3) Sensual experiences. Taken together these facets advance a kaleidoscopic perspective in which spatial, temporal and affective dimensions of the micro-practices of consumption territories-in-the-making are brought into view. Moreover, our empirical research adds an affective dimension to Brighenti’s theoretical elucidation of the formation and dissolution of territories, thereby incorporating sensual imaginations and bodily experiences into the assemblages of heterogeneous materials that sustain territories

    Exact and Truncated Dynamics in Nonequilibrium Field Theory

    Get PDF
    Nonperturbative dynamics of quantum fields out of equilibrium is often described by the time evolution of a hierarchy of correlation functions, using approximation methods such as Hartree, large N, and nPI-effective action techniques. These truncation schemes can be implemented equally well in a classical statistical system, where results can be tested by comparison with the complete nonlinear evolution obtained by numerical methods. For a 1+1 dimensional scalar field we find that the early-time behaviour is reproduced qualitatively by the Hartree dynamics. The inclusion of direct scattering improves this to the quantitative level. We show that the emergence of nonthermal temperature profiles at intermediate times can be understood in terms of the fixed points of the evolution equations in the Hartree approximation. The form of the profile depends explicitly on the initial ensemble. While the truncated evolution equations do not seem to be able to get away from the fixed point, the full nonlinear evolution shows thermalization with a (surprisingly) slow relaxation.Comment: 30 pages with 12 eps figures, minor changes; to appear in Phys.Rev.

    Toward an Integrated Competence-based System Supporting Lifelong Learning and Employability: Concepts, Model, and Challenges

    Get PDF
    Miao, Y., Van der Klink, M., Boon, J., Sloep, P. B., & Koper, R. (2009). Toward an Integrated Competence-based System Supporting Lifelong Learning and Employability: Concepts, Model, and Challenges. In M. Spaniol, Q. Li, R. Klamma & R. W. H. Lau (Eds.), Proceedings of the 8th International Conference Advances in Web Based Learning - ICWL 2009 (pp. 265-276). August, 19-21, 2009, Aachen, Germany. Lecture Notes in Computer Science 5686; Berlin, Heidelberg: Springer-Verlag.Efficient and effective lifelong learning requires that people can make informed decisions about their continuous personal development in the different stages of their lives. In this paper we state that lifelong learners need to be characterized as decision-makers. In order to improve the quality of their decisions we propose the development of an integrated lifelong learning and employment support system, which traces learners’ competence development and provides a decision support environment. An abstract conceptual model has been developed and the main design ideas have been documented using Z notation. Moreover, we analyzed the main technical challenges for the realization of the target system: competence information fusion, decision analysis models, spatial indexing structures and browsing structures and visualization of competence related information objects.The work on this publication has been sponsored by the TENCompetence Integrated Project that is funded by the European Commission's 6th Framework Programme, priority IST/Technology Enhanced Learning. Contract 027087 [http://www.tencompetence.org

    Zero mode in the time-dependent symmetry breaking of λϕ4\lambda\phi^4 theory

    Full text link
    We apply the quartic exponential variational approximation to the symmetry breaking phenomena of scalar field in three and four dimensions. We calculate effective potential and effective action for the time-dependent system by separating the zero mode from other non-zero modes of the scalar field and treating the zero mode quantum mechanically. It is shown that the quantum mechanical properties of the zero mode play a non-trivial role in the symmetry breaking of the scalar λϕ4\lambda \phi^4 theory.Comment: 10 pages, 3 figure

    Concentrating Membrane Proteins Using Asymmetric Traps and AC Electric Fields

    Get PDF
    Membrane proteins are key components of the plasma membrane and are responsible for control of chemical ionic gradients, metabolite and nutrient transfer, and signal transduction between the interior of cells and the external environment. Of the genes in the human genome, 30% code for membrane proteins (Krogh et al. J. Mol. Biol.2001, 305, 567). Furthermore, many FDA-approved drugs target such proteins (Overington et al. Nat. Rev. Drug Discovery2006, 5, 993). However, the structure-function relationships of these are notably sparse because of difficulties in their purification and handling outside of their membranous environment. Methods that permit the manipulation of membrane components while they are still in the membrane would find widespread application in separation, purification, and eventual structure-function determination of these species (Poo et al. Nature1977, 265, 602). Here we show that asymmetrically patterned supported lipid bilayers in combination with AC electric fields can lead to efficient manipulation of charged components. We demonstrate the concentration and trapping of such components through the use of a “nested trap” and show that this method is capable of yielding an approximately 30-fold increase in the average protein concentration. Upon removal of the field, the material remains trapped for several hours as a result of topographically restricted diffusion. Our results indicate that this method can be used for concentrating and trapping charged membrane components while they are still within their membranous environment. We anticipate that our approach could find widespread application in the manipulation and study of membrane proteins

    The Metal-Insulator Transition of NbO2: an Embedded Peierls Instability

    Full text link
    Results of first principles augmented spherical wave electronic structure calculations for niobium dioxide are presented. Both metallic rutile and insulating low-temperature NbO2, which crystallizes in a distorted rutile structure, are correctly described within density functional theory and the local density approximation. Metallic conductivity is carried to equal amounts by metal t_{2g} orbitals, which fall into the one-dimensional d_parallel band and the isotropically dispersing e_{g}^{pi} bands. Hybridization of both types of bands is almost negligible outside narrow rods along the line X--R. In the low-temperature phase splitting of the d_parallel band due to metal-metal dimerization as well as upshift of the e_{g}^{pi} bands due to increased p-d overlap remove the Fermi surface and open an optical band gap of about 0.1 eV. The metal-insulator transition arises as a Peierls instability of the d_parallel band in an embedding background of e_{g}^{pi} electrons. This basic mechanism should also apply to VO2, where, however, electronic correlations are expected to play a greater role due to stronger localization of the 3d electrons.Comment: 4 pages, revtex, 6 eps figures, additional material avalable at http://www.physik.uni-augsburg.de/~eyert

    Anomalous electric conductions in KSbO3-type metallic rhenium oxides

    Full text link
    Single crystals of KSbO3-type rhenium oxides, La4Re6O19,Pb6Re6O19,Sr2Re3O9andBi3Re3O11,weresynthesizedbyahydrothermalmethod.TheircrystalstructurescanberegardedasanetworkofthreedimensionalorthogonaldimerlatticeofedgesharedReO6octahedra.AllofthemexhibitsmallmagnitudeofPauliparamagnetism,indicatingmetallicelectronicstateswithoutstrongelectroncorrelations.Theresistivityoftheserhenates,exceptBi3Re3O11,haveatemperaturedependenceof19, Pb6Re6O19, Sr2Re3O9 and Bi3Re3O11, were synthesized by a hydrothermal method. Their crystal structures can be regarded as a network of three-dimensional orthogonal-dimer lattice of edge-shared ReO6 octahedra. All of them exhibit small magnitude of Pauli paramagnetism, indicating metallic electronic states without strong electron correlations. The resistivity of these rhenates, except Bi3Re3O11, have a temperature dependence of rho(T)=\rho_{0}+AT^{n} (n \approx 1.6)$ in a wide temperature range between 5 K and 300 K, which is extraordinary for three-dimensional metals without strong electron correlations. The resistivity of Bi3Re3O11 shows an anomaly around at 50 K, where the magnetic susceptibility also detects a deviation from ordinary Pauli paramagnetism.Comment: 13 pages, 7 figures. J. Phys. Soc. Japan, in pres
    corecore