[Experimental study of hypoxic pulmonary hypertension]

The dynamic changes in pulmonary vascular tone and reactivity of rats exposed to chronic hypobaric hypoxia were studied with cardiac catheterization and on perfusing isolated lung-preparations. It was found that their greatest rising appeared earlier than that of the pulmonary arterial pressure, and improving heart function might delay the development of hypoxic pulmonary hypertension. Whenever hypoxia was slight in extent, a compensatory increase in cardiac function was seen on the right side with no change in left heart. When hypoxia became more severe, an impairment of heart function occurred predominantly on the left side with or without decrease in the function of the right heart.

Uniform illumination of large targets using a lens array

Inserting an array of nearly 100 similar lenses into a common focal system, the uniformity of the illumination of a target can evidently be improved without being affected by the near-field distribution of laser beams. We report here geometrical- and physical-optics analyses of the lens array and compare them with the experimental results.