1,076 research outputs found

    A Novel Thermal Gradient Design for Small-bodied Ectotherms

    Get PDF
    For ectothermic organisms, environmental temperatures can influence a variety of life history traits. Experimental thermal gradients created in the laboratory are useful tools to examine the thermoregulatory behaviors of these organisms. Here, we provide details on the construction of a novel, cost-effective thermal gradient to study thermoregulatory behaviors in small-bodied nocturnal ectotherms

    Topological properties and fractal analysis of recurrence network constructed from fractional Brownian motions

    Full text link
    Many studies have shown that we can gain additional information on time series by investigating their accompanying complex networks. In this work, we investigate the fundamental topological and fractal properties of recurrence networks constructed from fractional Brownian motions (FBMs). First, our results indicate that the constructed recurrence networks have exponential degree distributions; the relationship between HH and canberepresentedbyacubicpolynomialfunction.Wenextfocusonthemotifrankdistributionofrecurrencenetworks,sothatwecanbetterunderstandnetworksatthelocalstructurelevel.Wefindtheinterestingsuperfamilyphenomenon,i.e.therecurrencenetworkswiththesamemotifrankpatternbeinggroupedintotwosuperfamilies.Last,wenumericallyanalyzethefractalandmultifractalpropertiesofrecurrencenetworks.Wefindthattheaveragefractaldimension can be represented by a cubic polynomial function. We next focus on the motif rank distribution of recurrence networks, so that we can better understand networks at the local structure level. We find the interesting superfamily phenomenon, i.e. the recurrence networks with the same motif rank pattern being grouped into two superfamilies. Last, we numerically analyze the fractal and multifractal properties of recurrence networks. We find that the average fractal dimension of recurrence networks decreases with the Hurst index HH of the associated FBMs, and their dependence approximately satisfies the linear formula 2H \approx 2 - H. Moreover, our numerical results of multifractal analysis show that the multifractality exists in these recurrence networks, and the multifractality of these networks becomes stronger at first and then weaker when the Hurst index of the associated time series becomes larger from 0.4 to 0.95. In particular, the recurrence network with the Hurst index H=0.5H=0.5 possess the strongest multifractality. In addition, the dependence relationships of the average information dimension andtheaveragecorrelationdimension and the average correlation dimension on the Hurst index HH can also be fitted well with linear functions. Our results strongly suggest that the recurrence network inherits the basic characteristic and the fractal nature of the associated FBM series.Comment: 25 pages, 1 table, 15 figures. accepted by Phys. Rev.

    Phenomenology of production and decay of spinning extra-dimensional black holes at hadron colliders

    Get PDF
    We present results of CHARYBDIS2, a new Monte Carlo simulation of black hole production and decay at hadron colliders in theories with large extra dimensions and TeV-scale gravity. The main new feature of CHARYBDIS2 is a full treatment of the spin-down phase of the decay process using the angular and energy distributions of the associated Hawking radiation. Also included are improved modelling of the loss of angular momentum and energy in the production process as well as a wider range of options for the Planck-scale termination of the decay. The new features allow us to study the effects of black hole spin and the feasibility of its observation in such theories

    Fatal and non-fatal drowning in rivers

    Get PDF

    Correlation entropy of synaptic input-output dynamics

    Full text link
    The responses of synapses in the neocortex show highly stochastic and nonlinear behavior. The microscopic dynamics underlying this behavior, and its computational consequences during natural patterns of synaptic input, are not explained by conventional macroscopic models of deterministic ensemble mean dynamics. Here, we introduce the correlation entropy of the synaptic input-output map as a measure of synaptic reliability which explicitly includes the microscopic dynamics. Applying this to experimental data, we find that cortical synapses show a low-dimensional chaos driven by the natural input pattern.Comment: 7 pages, 6 Figures (7 figure files

    Granger Causality and Cross Recurrence Plots in Rheochaos

    Get PDF
    Our stress relaxation measurements on wormlike micelles using a Rheo-SALS (rheology + small angle light scattering) apparatus allow simultaneous measurements of the stress and the scattered depolarised intensity. The latter is sensitive to orientational ordering of the micelles. To determine the presence of causal influences between the stress and the depolarised intensity time series, we have used the technique of linear and nonlinear Granger causality. We find there exists a feedback mechanism between the two time series and that the orientational order has a stronger causal effect on the stress than vice versa. We have also studied the phase space dynamics of the stress and the depolarised intensity time series using the recently developed technique of cross recurrence plots (CRPs). The presence of diagonal line structures in the CRPs unambiguously proves that the two time series share similar phase space dynamics.Comment: 10 pages, 7 figure

    Recurrence Analysis of Converging and Diverging Trajectories in the Mandelbrot Set

    Get PDF
    Iterated dynamics of the Mandelbrot set (M-set) were studied at paired points close to, but on either side of seven specific borders regions. Cross recurrence analysis of the real versus imaginary variables of the converging and diverging trajectories were found to be similar until the final divergence was manifested after hundreds of iterations. This study show that recurrence strategies can be used to study the sensitive dependence of M-set dynamics on initial conditions of the Mandelbrot chaotic attractor

    Recurrence Quantification Analysis of Human Gate Intervals

    Get PDF
    Human gate intervals of old and young subjects were studied using recurrence quantification analysis. Linear mean gate intervals were not significantly different between old and young subjects. However, nonlinear recurrence variables of Laminarity, Vmax and Traptime could distinguish between younger versus older subjects. Our findings support the conclusion that gate intervals in the younger people were more chaotic than the older individuals
    corecore