502,305 research outputs found

    Epidemic Model with Isolation in Multilayer Networks

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    The Susceptible-Infected-Recovered (SIR) model has successfully mimicked the propagation of such airborne diseases as influenza A (H1N1). Although the SIR model has recently been studied in a multilayer networks configuration, in almost all the research the isolation of infected individuals is disregarded. Hence we focus our study in an epidemic model in a two-layer network, and we use an isolation parameter to measure the effect of isolating infected individuals from both layers during an isolation period. We call this process the Susceptible-Infected-Isolated-Recovered (SIIRSI_IR) model. The isolation reduces the transmission of the disease because the time in which infection can spread is reduced. In this scenario we find that the epidemic threshold increases with the isolation period and the isolation parameter. When the isolation period is maximum there is a threshold for the isolation parameter above which the disease never becomes an epidemic. We also find that epidemic models, like SIRSIR overestimate the theoretical risk of infection. Finally, our model may provide a foundation for future research to study the temporal evolution of the disease calibrating our model with real data.Comment: 18 pages, 5 figures.Accepted in Scientific Report

    Radiation Effects on CMOS Image Sensors With Sub-2 µm Pinned Photodiodes

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    CMOS image sensor hardness under irradiation is a key parameter for application fields such as space or medical. In this paper, four commercial sensors featuring different technological characteristics (pitch, isolation or buried oxide) have been irradiated with 60Co source. Based on dark current and temporal noise analysis, we develop and propose a phenomenological model to explain pixel performance degradation

    Epidemic model with isolation in multilayer networks

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    The Susceptible-Infected-Recovered (SIR) model has successfully mimicked the propagation of such airborne diseases as influenza A (H1N1). Although the SIR model has recently been studied in a multilayer networks configuration, in almost all the research the isolation of infected individuals is disregarded. Hence we focus our study in an epidemic model in a two-layer network and we use an isolation parameter w to measure the effect of quarantining infected individuals from both layers during an isolation period tw. We call this process the Susceptible-Infected-Isolated-Recovered (SIIR) model. Using the framework of link percolation we find that isolation increases the critical epidemic threshold of the disease because the time in which infection can spread is reduced. In this scenario we find that this threshold increases with w and tw. When the isolation period is maximum there is a critical threshold for w above which the disease never becomes an epidemic. We simulate the process and find an excellent agreement with the theoretical results.We thank the NSF (grants CMMI 1125290 and CHE-1213217) and the Keck Foundation for financial support. LGAZ and LAB wish to thank to UNMdP and FONCyT (Pict 0429/2013) for financial support. (CMMI 1125290 - NSF; CHE-1213217 - NSF; Keck Foundation; UNMdP; Pict 0429/2013 - FONCyT)Published versio

    Clinical parameters as predictors of bacterial isolation in the uterine content of dogs suspected of pyometra

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    In this study, female canines referred with clinical signs consistent with pyometra were prospectively evaluated. Signalment, clinical signs, laboratory findings and surgical findings were compared between dogs with and without bacterial isolation based on aerobic techniques. Patients with positive bacterial isolation were placed in the pyometra group, whereas patients with negative bacterial isolation were grouped as mucometra. A total of 140 dogs (118 with pyometra and 22 with mucometra) met the inclusion criteria. Prereferral antibiotic administration was associated with a prolonged duration of clinical signs in the patients of the pyometra group (12 +/- 2 days versus 7 +/- 1 days; P=0.006). In the pyometra patients, clinical signs, like pyrexia, anorexia and discomfort on abdominal palpation, were observed more commonly than in the mucometra group. The total leukocyte count was the only parameter that differed significantly between the two groups (P=0.01). Although no difference in color and consistency of the uterine fluid was noted, the uteri of the pyometra group were heavier (851.80 +/- 800.30 g compared to 263.50 +/- 297.10 g). E. coil was the most commonly isolated bacterium (92/123)

    Switching Control for Parameter Identifiability of Uncertain Systems

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    This paper considers the problem of identifying the parameters of an uncertain linear system by means of feedback control. The problem is approached by considering time-varying controllers. It is shown that even when the uncertainty set is not finite, parameter identifiability can be generically ensured by switching among a finite number of linear time-invariant controllers. The results are shown to have several implications, ranging from fault detection and isolation to adaptive and supervisory control. Practical aspects of the problem are also discussed in details

    Predicting and controlling the dynamics of infectious diseases

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    This paper introduces a new optimal control model to describe and control the dynamics of infectious diseases. In the present model, the average time of isolation (i.e. hospitalization) of infectious population is the main time-dependent parameter that defines the spread of infection. All the preventive measures aim to decrease the average time of isolation under given constraints

    Isolated Prompt Photon Production in Hadronic Final States of e+ee^+e^- Annihilation

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    We provide complete analytic expressions for the isolated prompt photon production cross section in e+ee^+e^- annihilation reactions through one-loop order in quantum chromodynamics (QCD) perturbation theory. Functional dependences on the isolation cone size δ\delta and isolation energy parameter ϵ\epsilon are derived. The energy dependence as well as the full angular dependence of the cross section on θγ\theta_\gamma are displayed, where θγ\theta_\gamma specifies the direction of the photon with respect to the e+ee^+e^- collision axis. We point out that conventional perturbative QCD factorization breaks down for isolated photon production in e+ee^+e^- annihilation reactions in a specific region of phase space. We discuss the implications of this breakdown for the extraction of fragmentation functions from e+ee^+e^- annihilation data and for computations of prompt photon production in hadron-hadron reactions.Comment: 54 pages RevTeX plus 19 postscript figures submitted together in one compressed fil
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