Proposal for a Trigonometric Method to Evaluate the Abduction Angle of the Lower Limbs in Neonates

It is difficult to precisely measure articular arc movement in newborns using a goniometer. This article proposes an objective method based on trigonometry for the evaluation of lower limb abduction. With the newborn aligned in the dorsal decubitus position, 2 points are marked at the level of the medial malleolus, one on the sagittal line and the other at the end of the abduction. Using the right-sided line between these 2 points and a line from the medial malleolus to the reference point at the anterior superior iliac spine or umbilical scar, an isosceles triangle is drawn, and half of the inferential abduction angle is obtained by calculating the sine. Twenty healthy full-term newborns comprise the study cohort. Intersubject and intrasubject variability among the abduction angle values (mean [SD], 37 degrees [4]degrees) is low. This method is advantageous because the measurement is precise and because the sine can be used without approximation.

FURTHER INSIGHTS TOWARD VITAMIN C DETERMINATION AND STABILITY. PROPOSAL OF A NEW QUANTIFICATION METHOD

This work aimed at an evaluation of the classical iodine method for quantification of vitamin C (L-ascorbic acid) in fruit juices, as well as at a search into the stability of this so popular vitamin under different conditions of pH, temperature and light exposition, in addition to a proposal of a new quantification method. Our results point to the persistent reversibility of the blue color of the starch-triiodide complex at the end point when using the classical iodine titration, and the overestimation of the true vitamin concentration in fruit juices. A new quantification method is proposed in order to overcome this problem. Surprising conclusions were obtained regarding the controversial stability of L-ascorbic acid toward atmospheric oxygen, at low pH, even in fruit juice and at room temperature, showing that the major problem concerned with aging of fruit juices is proliferation of microorganisms rather than expontaneous oxidation of L-ascorbic acid.