Many organisms display rhythms of physiology and behavior that are entrained to the 24-h cycle of light and darkness prevailing on Earth. Under constant conditions of illumination and temperature, these internal biological rhythms persist with a period close to 1 day ("circadian"), but it is usually not exactly 24h. Recent discoveries have uncovered… (More)
Some of the events of the cell cycle appear to be triggered by a bistable mechanism. A bistable biochemical system can respond to a small, slow signal and is carried by positive feedback from one stable steady state directly to another, in an all-or-none manner. Slow or subthreshold stimuli do not cause accommodation or loss of excitability. Switching is… (More)
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In mammalian cells, the heterodimeric kinase cyclin E/CDK2 (EK2) mediates cell cycle progress from G1 phase into S phase. The protein p27Kip1 (p27) binds to and inhibits EK2; but EK2 can phosphorylate p27, and that leads to the deactivation of p27, presumably liberating more EK2 and forming a positive-feedback loop. It has been proposed that this… (More)
We introduce the Padé–Z 2 (PZ) stochastic estimator for calculating determinants and determinant ratios. The estimator is applied to the calculation of fermion determinants from the two ends of the Hybrid Monte Carlo trajectories with pseudofermions. Our results on the 8 3 × 12 lattice with Wilson action show that the statistical errors from the stochastic… (More)
especially those papers emphasizing adaptive and integrative mechanisms. It is published 12 times a year (monthly) by publishes original papers that deal with diverse area of research in applied physiology,
The problem of placement of mesh router nodes in Wireless Mesh Networks is known to be a NP hard problem. In this paper, the problem is addressed under a constraint of network model tied to rural regions where we usually observe low density and sparse population. We consider the area to cover as decomposed into a set of elementary areas which can be… (More)
Wireless mesh networks appear as an appealing solution to reduce the digital divide between rural and urban regions. However the placement of router nodes is still a critical issue when planning this type of network, especially in rural regions where we usually observe low density and sparse population. In this paper, we firstly provide a network model tied… (More)