The analysis of almost a century-long evolution ideas about the criteria for activity Rheumatoid Arthritis showed that developed complex indices determination there are far from perfect, in particular Disease Activity.

The circular chromatic number of a graph is a well-studied refinement of the chromatic number. Circular-perfect graphs form a superclass of perfect graphs defined by means of this more general coloring concept. This paper studies claw-free circular-perfect graphs. First we prove that ifG is a connected claw-free circular-perfect graph with χ(G) > ω(G), then min{α(G), ω(G)} = 2. We use this resu...