Effect of differing facial characteristics on breathing resistance inside a respirator mask.

A group of subjects with a large range of facial characteristics was asked to breathe deeply while wearing a full facepiece respirator. The facial characteristics noted were head length, head depth, bizygomatic breadth, lip length, and Menton-Sellion length. External resistances to inhalation or exhalation were varied in each of the trials.

Telephone communications with several commercial respirators.

Previous work showed that telephone communications while wearing military respirators degraded both word comprehension and recognition speed. In addition, electronic amplification of the speech diaphragm signal had shown no advantage to the extra hardware. This experiment was performed to test effects of different configurations of commercially available respirators on telephone communications accuracy and speed.

Management dilemmas in the individual with cystic fibrosis and diabetes.

As their life expectancy has improved, patients with cystic fibrosis (CF) have experienced an increasing incidence of diabetes. Hyperglycemia may adversely influence weight, pulmonary function, and development of microvascular complications. Strict control of blood glucose has not universally been sought, however.

Optical distortions and birefringence in high power laser windows: model and computer code.

A general optical model is given which predicts optical wave front distortions and birefringence due to stress and temperature variations in laser heated and pressure loaded windows for cubic lattice window materials. A computer code is described that integrates stress and thermal computations with an optical model to predict the wave front distortions. Restrictive approximations, which have been used previously to predict window temperature and stress distributions, are avoided by using stress and thermal codes to predict these distributions within the windows.