THE INFLUENCE OF TURBULENT FLOW ON THE SENSORY ASSESSMENT OF VISCOSITY IN THE MOUTH.

Low viscosity Newtonian fluids exhibit turbulence in a cone-plate viscometer at high rates of shear which are comparable to those operating in the mouth during sensory assessment of the viscosity of the same fluids. Saliva reduces this effect to some small extent, possibly due to its content of mucin and other proteinaceous substances. The net result is that these fluids appear to have a higher viscosity in the mouth than when they are examined in a viscometer at low rates of shear.

Effects of oral contraceptives on human plasma vitamin-A levels.

Vitamin-A levels have been determined in healthy non-pregnant women and in women taking synthetic steroids to suppress ovulation. A significant increase has been found in those receiving oral contraceptives. Further work is necessary to determine whether this may affect the fetus in patients who become pregnant shortly after discontinuing oral contraception.

FAT CRYSTALS AND THE FLOW RHEOLOGY OF BUTTER AND MARGARINE.

The viscosities of fat crystals extracted by 1 % Aerosol O.T. from butter and margarine have been studied using a Weissenberg Rheogoniometer.