Quiescent state

Specifically, a given site becomes active on the next time step if at least one of its neighbors is already active otherwise it becomes quiescent (cr = 0). Once a given site has become active, it becomes refractory a = 2) on the next time step. Refractory sites are both insensitive to the values of neighboring sites and incapable of activating them. Upon becoming refractory, sites attain the quiescent state on the next time step. 

The unique, compact and efficient design of a circular DAF cell is made possible by using the principle of zero velocity. As mentioned earlier, the influent distribution duct moves backward with the same velocity as the forward incoming water. The zero velocity quiescent state in the flotation chamber is thus created ideally for flotation. 

Kramer, et al.(262,327) and Knoll(233), on the basis of G, G response concluded that gels kept in continuous motion during the crosslink formation period have completely different 3-D networks than gels allowed to stand in a quiescent state prior to analysis on the rheometer. This observation confirmed the early comments of Conway(317) and has had important implications for fracturing gel research and modeling since crosslinked fracturing gels as applied in the field ordinarily do not experience a quiescent period, yet nearly all test data accumulated prior to 1986 was collected from samples that had experienced at least a momentary quiescent period. 

The lamellar thickening proceeds through many metastable states, each metastable state corresponding to a particular number of folds per chain, as illustrated in Fig. 8. In the original simulations of [22], Kg was monitored. Rg is actually very close to the lamellar thickness due to the asymmetric shape of the lamella. The number of folds indicated in Fig. 8 were identified by inspection of the coordinates of the united atoms. This quantization of the number of folds has been observed in experiments [50], as already mentioned. The process by which a state with p folds changes into a state with p - 1 folds is highly cooperative. The precursor lives in a quiescent state for a substantial time and suddenly it converts into the next state. By a succession of such processes, crystals thicken. If the simulation is run for a reasonably long time, the lamella settles down to the equilibrium number of folds per chain. 

Galgali and his colleagues [46] have also shown that the typical rheological response in nanocomposites arises from frictional interactions between the silicate layers and not from the immobilization of confined polymer chains between the silicate layers. They have also shown a dramatic decrease in the creep compliance for the PP-based nanocomposite with 9 wt% MMT. They showed a dramatic three orders of magnitude drop in the zero shear viscosity beyond the apparent yield stress, suggesting that the solid-like behavior in the quiescent state is a result of the percolated structure of the layered silicate. 

RPTK activation. The activity of RPTKs is normally suppressed in their quiescent state. This suppression is due to the numerous loose and unstructured conformations of the activation loop (A loop) within the catalytic domain the majority of these conformations interfere with substrate and ATP binding. However, a subset of these conformations is amenable to binding of substrate and ATP, resulting in activation of the RPTKs. Phosphorylation of the tyrosine residue(s) in the A loop shifts the equilibrium towards the active conformation. Because of steric hindrance, PTK catalytic domains appear to be unable to autophosphorylate tyrosine residue(s) in the A loop within the same molecule rather frans-autophosphoryla-tion between two different catalytic domains is necessary for their activation. As a consequence, ligand-induced dimerization is an important step in the activation of RPTKs (Fig. 24-7). 

Sizing of vent areas The empirical equation (23-12) can be used to calculate the required vent area for flammable gas or solvent vapor explosions. The equation is valid for flammable gas-air mixtures which have been ignited in a quiescent state (nonturbulent) with an ignition source of E = 10 J. 

At low concentrations, when uncharged polymers are dissolved in a solvent in which they do not crosslink or entangle, they possess a viscoelastic response through hydrodynamic and entropic effects. We can begin by considering an isolated chain in its quiescent state. The chain will be in constant motion. In the absence of any specific interactions, the chain will evolve to its maximum entropy state. We can represent the chain as N links or submolecules each with a length b. These links are formed from a few monomer units of the chain. The root mean square end-to-end length of the chain is... 

In most cell types, two further phases can be distinguished, Gi and G2 phase. Gi phase includes the period between M phase and S phase G2 phase covers the period between S phase and M phase. From Gi phase, the cell may transfer into a quiescent state known as Go phase. Appropriate signals (e.g., addition of growth factors) can induce the cell to return from Go into Gi phase and proceed with the cell cycle. 

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