Coal forms from the accumulation of plant debris, usually in a swamp environment. When plant debris dies and falls into the swamp the standing water of the swamp protects it from decay. Swamp waters are usually deficient in oxygen, which would react with the plant debris and cause it to decay.
Porokeratosis is generally considered to be a benign condition though malignant transformation has been seen in all but the punctate variety, necessitating regular followup of patients with porokeratosis (Maubec et al., 2005; Sasson & Krain, 1996).
Poria Cocos. Poria cocos may be called Poria, Tuckahoe, Indian bread or Fu-Ling in Chinese. Poria cocos is a mushroom which is used in traditional Chinese medicine and has been widely accepted in modern medicine as a treatment for inflammation and as a central nervous system depressant. Poria cocos looks like a potato that may be seen growing in pine tree roots and dead barks.