4,789 research outputs found

    Polarized ensembles of random pure states

    Full text link
    A new family of polarized ensembles of random pure states is presented. These ensembles are obtained by linear superposition of two random pure states with suitable distributions, and are quite manageable. We will use the obtained results for two purposes: on the one hand we will be able to derive an efficient strategy for sampling states from isopurity manifolds. On the other, we will characterize the deviation of a pure quantum state from separability under the influence of noise.Comment: 14 pages, 1 figur

    Local Hamiltonians for Maximally Multipartite Entangled States

    Full text link
    We study the conditions for obtaining maximally multipartite entangled states (MMES) as non-degenerate eigenstates of Hamiltonians that involve only short-range interactions. We investigate small-size systems (with a number of qubits ranging from 3 to 5) and show some example Hamiltonians with MMES as eigenstates.Comment: 6 pages, 3 figures, published versio

    Market organization and propagation of shocks: the furniture industry in Germany and Italy

    Get PDF
    In this paper we study the furniture industry in two European countries, Germany and Italy. Although the two industries are characterized by very similar output and technology, they differ widely in terms of market organization, most notably the distribution of firms by size, and the organization of retail. We find some evidences that these differences have an influence on the dynamic behavior of industry output, prices and exports in the two countries

    The APC/C Coordinates Retinal Differentiation with G1 Arrest through the Nek2-Dependent Modulation of Wingless Signaling

    Get PDF
    The cell cycle is coordinated with differentiation during animal development. Here we report a cell-cycle-independent developmental role for a master cell-cycle regulator, the anaphase-promoting complex or cyclosome (APC/C), in the regulation of cell fate through modulation of Wingless (Wg) signaling. The APC/C controls both cell-cycle progression and postmitotic processes through ubiquitin-dependent proteolysis. Through an RNAi screen in the developing Drosophila\textit{Drosophila}eye, we found that partial APC/C inactivation severely inhibits retinal differentiation independently of cell-cycle defects. The differentiation inhibition coincides with hyperactivation of Wg signaling caused by the accumulation of a Wg modulator, Drosophila\textit{Drosophila} Nek2 (dNek2). The APC/C degrades dNek2 upon synchronous G1 arrest prior to differentiation, which allows retinal differentiation through local suppression of Wg signaling. We also provide evidence that decapentaplegic signaling may posttranslationally regulate this APC/C function. Thus, the APC/C coordinates cell-fate determination with the cell cycle through the modulation of developmental signaling pathways.T.M. and F.M. were partly supported by a CRUK Fellowship to Y.K. T.M. thanks the European Commission for a Marie Curie fellowship

    Blow-up of the quantum potential for a free particle in one dimension

    Get PDF
    We derive a non-linear differential equation that must be satisfied by the quantum potential, in the context of the Madelung equations, in one dimension for a particular class of wave functions. In this case, we exhibit explicit conditions leading to the blow-up of the quantum potential of a free particle at the boundary of the compact support of the probability density

    A model for trustworthy orchestration in the internet of things

    Get PDF
    Embedded systems such as Cyber-Physical Systems (CPS) are typically designed as a network of multiple interacting elements with physical input (or sensors) and output (or actuators). One aspect of interest of open systems is fidelity, or the compliance between physical figures of interest and their internal representation. High fidelity is defined as a stable mapping between actions in the physical domain and intended or expected values in the system domain and deviations from fidelity are quantifiable over time by some appropriate informative variable. In this paper, we provide a model for designing such systems based on a framework for trustworthiness monitoring and we provide a Jason implementation to evaluate the feasibility of our approach. In particular, we build a bridge between a standard publish/subscribe framework for CPS called MQTT and Jason to enable automatic reasoning about trustworthines

    Binary mixtures of condensates in generic confining potentials

    Full text link
    We study a binary mixture of Bose-Einstein condensates, confined in a generic potential, in the Thomas-Fermi approximation. We search for the zero-temperature ground state of the system, both in the case of fixed numbers of particles and fixed chemical potentials.Comment: 20 pages, 2 figure

    Quality of institutions and productivity of State-Invested Enterprises: International evidence from major telecom companies

    Get PDF
    The quality of institutions is at the core of the differences in the growth of income and productivity of nations. A growing body of evidence shows how this is also true at the firm level. After taking stock of earlier theoretical and empirical literature on the efficiency of state-owned versus private enterprises, while we consider ownership as the core internal governance mechanism of firms, we add quality of government as a determinant of the external institutional environment. To disentangle the effect of internal and external institutions on firms' productivity, we use different sets of ownership and institutional environment indicators. After having identified the top 350 private, state-invested (i.e. partially state-owned)and state-owned enterprises in the telecommunications industry in EU28 and in more than 60 other countries between 2007 and 2015, we empirically investigate models of firms' productivity augmented with ownership and quality of government. Our findings suggest that, after controlling for the regulatory and competitive conditions at the country level, on average, public ownership has a negative impact on firm-level TFP. This effect is however mitigated by high external institutional quality and even reversed in some countries with a particularly favourable institutional environment

    INVESTIGATIONS ON THE DESIGN PROCESS OF ELADIO DIESTE: 3D PARAMETRIC MODELLING OF MODERN LATIN AMERICAN ARCHITECTURAL HERITAGE

    Get PDF
    Abstract. The Uruguayan Engineer Eladio Dieste underwent a quest for thinness in the field of structural design which rendered his reinforced masonry thin-shell structures at a conspicuous position in Modern Latin American Architectural Heritage, so much so as to have Dieste's work in Latin America and Europe included in an indicative list for UNESCO's cultural heritage sites as of 2010. Nonetheless, the design process that led Dieste to such innovative structural typologies is yet to be fully academically explored. Thus, the objective of this paper is to examine the state-of-art regarding the intricate design process of Eladio Dieste's gaussian vaults and shed some light on the existing gaps within this process by means of the 3D parametric modelling and digital fabrication of selected case studies. The adoption methodological procedures such as 3D parametrical modelling and digital fabrication allows for the establishment of important relationships between the design process and the resulting geometry of Eladio Dieste's designs, as well as furthering registry of Dieste's legacy for conservation purposes.</p
    • …
    corecore