In the contex of the six confirmations, what is the meaning of transformation?

What is the meaning of, to transform from the middle or to transform from the root?

"Yang ming & Jue Yin do not transform from the root or manifestation, but from their middle."

Huangdi Neijing Suwen Chapter 74.

Jue Yin middle or Zhong Chi is Shao Yang Fire. This I can understand. That Liver & Pericardium manifest as Gall Bladder & Tripple Heater.

But Yang Ming middle or Zhong Chi is Tai Yin Dampness. 

How is Yang Ming fever or constipation the manifestation of damp?

 Phil Baxter. Byron Bay Australia