Online research in philosophy

This paper explores the consequences of the theoretical forward activation enzymatic pathway A 0 A 1 A 2 A 3 where E 1 convents A 0 to A 1, E 2 converts A 1 to A 2 and E 3 converts A 2 to A 3. A 0, which is environmentally determined, also serves to activate (or modulate) the activity of E 3 in such a way as to keep the concentration of A 2 ([A 2]) constant at a particular (...) set-point value. For mathematical simplicity, first order rate kinetics are used where k 1, k 2 and k 3 are the rate constants for E 1, E 2, and E 3 respectively. It is shown that if k 3 is modulated appropriately so as keep [A 2] at the setpoint value with a changing upstream [A 0], then the modulation of k 3 must be anticipatory of the dynamics of the biochemical pathway. In other words, the rate of change of k 3, will be a function of [A 0], k 1, k 2, k 3, and the set-point value of [A 2]. If the modulation of k 3 does not perfectly model (anticipate) the reaction pathway of which it is a part, then the actual [A 2] will deviate from the set-point value. This type of anticipatory feed-forward activation may represent an important aspect of biological organization. (shrink)

Kinetic models using enzyme kinetics are developed for the three ways that Louie proved that Rosen’s minimal (M-R)-System can be closed to efficient cause; i.e., how the “replication” component can itself be entailed from within the system. The kinetic models are developed using the techniques of network thermodynamics . As a demonstration, each model is simulated using a SPICE circuit simulator using arbitrarily chosen rate constants. The models are built from SPICE sub-circuits representing the key terms in the chemical rate (...) equations. The models include the addition of an ad hoc semi-permeable membrane so the system can achieve steady state fluxes and also to illustrate the need for all the efficient cause agents to be continually replaced. Comments are made about exactly what is being simulated. (shrink)