Generally speaking, the vertical axis of a tropical cyclone, usually defined by the location of minimum wind or minimum pressure. The cyclone center position can vary with altitude. In advisory products, refers to the center position at the surface.
Facts on vitamin A and psoriasis. 1  Vitamin A can be very effective in treating psoriasis. 2  Creams and tablets can be prescribed. 3  High doses of Vitamin A should only be given under specialist supervision.  A combination of Vitamin A and phototherapy (light treatment) can give excellent results of most patients.
Vitamin D deficiencies are common in people with psoriatic arthritis, a 2011 study found, but it wasn't clear why. (Because sun exposure ups the body's vitamin D, spending time indoors can lead to a deficiency.) The same study found that vitamin D levels didn't seem to affect disease activity.