7,839 research outputs found

    Lost in Transition? The returns to education acquired under communism 15 years after the fall of the Berlin Wall

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    Using data for 23 economies in Eastern and Western Europe, we find evidence that having studied under communism is relatively penalized in the economies of the late 2000s. This evidence, however, is limited to males and to primary and secondary education, and holds for eight CEE economies but not for the East Germans who have studied in the former German Democratic Republic. We also find that post-secondary education acquired under communism yields higher, not lower, payoffs than similar education in Western Europe.

    Lost in Transition? The Returns to Education Acquired under Communism 15 Years after the Fall of the Berlin Wall

    Get PDF
    Using data for 22 economies in Eastern and Western Europe, we find evidence that having studied under communism is relatively penalized in the economies of the late 2000s. This evidence, however, is limited to males and to primary and secondary education, and holds for eight CEE economies but not for the East Germans who have studied in the former German Democratic Republic. We also find that post-secondary education acquired under communism yields higher, not lower, payoffs than similar education in Western Europe.returns to education, Eastern Europe

    Organization and evolution of synthetic idiotypic networks

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    We introduce a class of weighted graphs whose properties are meant to mimic the topological features of idiotypic networks, namely the interaction networks involving the B-core of the immune system. Each node is endowed with a bit-string representing the idiotypic specificity of the corresponding B cell and a proper distance between any couple of bit-strings provides the coupling strength between the two nodes. We show that a biased distribution of the entries in bit-strings can yield fringes in the (weighted) degree distribution, small-worlds features, and scaling laws, in agreement with experimental findings. We also investigate the role of ageing, thought of as a progressive increase in the degree of bias in bit-strings, and we show that it can possibly induce mild percolation phenomena, which are investigated too.Comment: 13 page

    Cosmic ray production in modified gravity

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    This paper is a reply to the criticism of our work on particle production in modified gravity by D. Gorbunov and A. Tokareva. We show that their arguments against efficient particle production are invalid. F(R)F(R) theories can lead to an efficient generation of high energy cosmic rays in contracting systems.Comment: In response to criticism by referees several clarifying comments are added. The results of the paper remain largely unchanged. Version to appear on EPJ

    Update on the GRB universal scaling EX,iso_{\rm{X,iso}}-Eγ,iso_{\rm{\gamma,iso}}-Epk_{\rm{pk}} with ten years of SwiftSwift data

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    From a comprehensive statistical analysis of SwiftSwift X-ray light-curves of gamma-ray bursts (GRBs) collected from December 2004 to the end of 2010, we found a three-parameter correlation between the isotropic energy emitted in the rest frame 1-104^4 keV energy band during the prompt emission (Eγ,iso_{\rm{\gamma,iso}}), the rest frame peak of the prompt emission energy spectrum (Epk_{\rm{pk}}), and the X-ray energy emitted in the rest frame 0.3-30 keV observed energy band (EX,iso_{\rm{X,iso}}), computed excluding the contribution of the flares. In this paper, we update this correlation with the data collected until June 2014, expanding the sample size with \sim35% more objects, where the number of short GRBs doubled. With this larger sample we confirm the existence of a universal correlation that connects the prompt and afterglow properties of long and short GRBs. We show that this correlation does not depend on the X-ray light-curve morphology and that further analysis is necessary to firmly exclude possible biases derived by redshift measurements. In addition we discuss about the behavior of the peculiar objects as ultra-long GRBs and we propose the existence of an intermediate group between long and short GRBs. Interestingly, two GRBs with uncertain classification fall into this category. Finally, we discuss the physics underlying this correlation, in the contest of the efficiency of conversion of the prompt γ\gamma-ray emission energy into the kinetic energy of the afterglow, the photosferic model, and the cannonball model.Comment: 11 pages, 5 figures, accepted for publication in MNRA

    Complete integrability of information processing by biochemical reactions

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    Statistical mechanics provides an effective framework to investigate information processing in biochemical reactions. Within such framework far-reaching analogies are established among (anti-) cooperative collective behaviors in chemical kinetics, (anti-)ferromagnetic spin models in statistical mechanics and operational amplifiers/flip-flops in cybernetics. The underlying modeling -- based on spin systems -- has been proved to be accurate for a wide class of systems matching classical (e.g. Michaelis--Menten, Hill, Adair) scenarios in the infinite-size approximation. However, the current research in biochemical information processing has been focusing on systems involving a relatively small number of units, where this approximation is no longer valid. Here we show that the whole statistical mechanical description of reaction kinetics can be re-formulated via a mechanical analogy -- based on completely integrable hydrodynamic-type systems of PDEs -- which provides explicit finite-size solutions, matching recently investigated phenomena (e.g. noise-induced cooperativity, stochastic bi-stability, quorum sensing). The resulting picture, successfully tested against a broad spectrum of data, constitutes a neat rationale for a numerically effective and theoretically consistent description of collective behaviors in biochemical reactions.Comment: 24 pages, 10 figures; accepted for publication in Scientific Report

    Chronic diseases and labor market outcomes in Egypt

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    By causing a sizeable reduction in employment 6 percent and labor supply 19 percent, chronic diseases are responsible for a major efficiency loss in the Egyptian economy. Furthermore the impact of chronic diseases on the labor market is not uniformly distributed. The older and the less educated suffer a larger drop in the probability of being employed and in their supply of working hours. The authors estimate the reduced form equations of individual employment status, labor supply and the usual wage equation. They control for unobserved ability and individual preferences by means of a within-siblings estimator. Measurement errors in our self-reported health variable have been accounted for.Health Monitoring&Evaluation,Labor Markets,Disease Control&Prevention,Labor Policies,Population Policies
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