Time-scales of viral evolution and emergence have been studied widely, but are often poorly understood. Molecular analyses of viral evolutionary time-scales generally rely on estimates of rates of nucleotide substitution, which vary by several orders of magnitude depending on the timeframe of measurement. We analysed data from all major groups of viruses and found a strong negative relationship...

Cardiovascular function is regulated by the rhythmicity of circadian, infradian and ultradian clocks. Specific time scales of different cell types drive their functions: circadian gene regulation at hours scale, activation-inactivation cycles of ion channels at millisecond scales, the heart's beating rate at hundreds of millisecond scales, and low frequency autonomic signaling at cycles of tens...

BACKGROUND Prognostic scales provide a useful tool to predict mortality in community-acquired pneumonia (CAP). However, the inflammatory response of the host, crucial in resolution and outcome, is not included in the prognostic scales. METHODS The aim of this study was to investigate whether information about the initial inflammatory cytokine profile and markers increases the accuracy of prog...

Closed-loop input rate regulation schemes have come to play an important role in the transport of the Available Bit Rate (ABR) traac service category for ATM. In this paper, we present a numerical approach to the performance study of a delayed feedback system with one congested node and multiple connections. This approach consists in modeling the feedback system as a nite Quasi-Birth-Death (QBD...

Recent single-molecule enzymology measurements with improved statistics have demonstrated that a single enzyme molecule exhibits large temporal fluctuations of the turnover rate constant at a broad range of time scales (from 1 ms to 100 s). The rate constant fluctuations, termed as dynamic disorder, are associated with fluctuations of the protein conformations observed on the same time scales. ...

We demonstrate that at long times the rate of passive scalar decay in a turbulent, or simply chaotic, flow is dominated by regions where mixing is less efficient. We examine two situations. The first is of a spatially homogeneous stationary turbulent flow with both viscous and inertial scales present. It is shown that at large times scalar fluctuations decay algebraically in time at all spatial...

This paper discusses some issues and possibilities for more eeective ABR (Available Bit Rate) traac management which arise from a careful consideration of various time scales present in an ATM networking environment. Since the ABR applications will typically use the remaining resources after CBR (Constant Bit Rate) and VBR (Variable Bit Rate) applications have been accommodated, the ABR rate sh...