Autocatalytic trigger

We will leave it to the reader (as a simple but useful exercise) to enumerate all the cycles in all the graphs depicted in Figs. 1 and 2 and also for the Prigogine autocatalytic trigger [6] ... 

How can negative fluctuations in entropy production occur or be triggered As Manfred Eigen shows in his evolution theory, fluctuations in entropy production can be caused by the coming into being of a self-replicating molecular species which is capable of selection. Autocatalytically active mutants can also have the same effect. Looked at this way, the phenomenon of evolution consists of a continuous series of instabilities, i.e., collapses of stationary states. 

While the exact mechanism of ceramide-mediated regulation of most of the above proteins is still unknown, ASM-released ceramide binds directly to PLAa and cathepsin D (Huwiler et al, 2001 Heinrich et al., 1999). Binding of ceramide to cathepsin D in endosomes triggers autocatalytic cleavage of cathepsin to its active form (Heinrich et al, 1999). However, the physiological role of ceramide binding to cathepsin D and PLA2 for apoptosis stiU remains to be determined. 

In the SOS system, multiple unlinked genes repressed by a single repressor are induced simultaneously when DNA damage triggers RecA protein-facilitated autocatalytic proteolysis of the repressor. 

Since this thermogram shows a steep peak, the autocatalytic nature of the decomposition is likely. Thus, two isothermal DSC experiments were performed at 240 and 250 °C, in order to confirm this hypothesis and to evaluate the probability of triggering the decomposition (Figure 12.13). The results can be summarized as follows at 240°C the initial heat release rate is 8.5 Wkg-1 and the maximum heat release rate 260 Wkg-1. At 250°C, the measured heat release rates are 15 and 360Wkg 1, respectively. 

A catalytic amount of TBAF is effective in the allylation of aromatic imines with 10 in refluxing THF." Similar to the TBAF-catalyzed carbonyl allylation, the imine allylation is promoted by a fluoride-triggered autocatalytic cycle. 

TBAF is an effective catalyst for the allylation of aromatic imines wifh allylsilanes (Scheme 10.149) [421]. In the presence of 4-A MS and 1 mol% TBAF, allyl-trimefhylsilane smoothly reacts with aromatic imines in THF under reflux to give the corresponding homoallylamines. The mechanism of allylation of imines can be reasonably interpreted in terms of a fluoride-triggered autocatalytic cycle. 

Jorne (1980) confirmed the findings of earlier researchers that the trigger wave propagation in the ferroin catalyzed B-Z reaction is caused by the coupling between autocatalytic mechanism and diffusion. 

Stereoselective aldol reactions, allylations, and aziridinations of imines, including activated imines, have been reported." The Sakurai-Hosomi reaction of aUylsilane with imine in the presence of tetrabutylammonium fluoride is found not to be strictly catalysed by fluoride rather, a fluoride-triggered autocatalytic route is suggested. 

A fluoride-triggered autocatalytic process (Scheme 16) has been proposed to account for the formation of homoallylamines (115) on reaction of allyltrimethylsilane (113) with aldimines (114) in the presence of TBAF this represents the first non-Lewis acid-mediated allylation of aldimines by allylsilane. ... 

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