A class of linear positive, trace preserving maps in Mn is given in terms of affine maps in R n 2 −1 which map the closed unit ball into itself.

The relationship between blood viscosity, hematocrit (Hct), and mean arterial blood pressure (MAP) was studied in a healthy population of 91 men and 66 women with an average age of 30.6 ± 8.0 years, from the city of Victoria de Durango (1800 m elevation). In women and men, Hct values were 42.4% ± 2.9% and 47.2% ± 2.3%, blood viscosities were 4.5 ± 0.7 and 6.1 ± 1.0 cP, and MAP was 83.0 ± 6.8 an...