Analysis of systemic effects of dioxin on human health through template-and-anchor modeling
Fig 5
The variables correspond to the processes in Fig 4. Specifically, Dietary intake: X0; Cholesterol biosynthesis: X1; Cholesterol storage: X2; Peripheral cholesterol utilization: X3; Plasma transport and conversion of cholesterol: X4; Steroid hormone production: X5; Excretion: X6. The hollow arrows represent the hand-over of cholesterol from one process to another. Each activation arrow (green, dashed) represents a positive effect of the source process on the target process. For example, dietary cholesterol intake leads to increased cholesterol storage. An inhibition arrow (red, dashed, blunted) indicates that the source process affects the target process. For example, dietary intake of cholesterol reduces the rate of cholesterol biosynthesis. Once it is clear that the variables represent processes, the mathematical implementation in BST follows the same guidelines as for a traditional model: The change in the rate of a process is driven by increasing and decreasing influences, and each term describing these influences is modeled as a power-law term containing a rate constant and those variables (processes) that directly affect the term in question, raised to an appropriate power.