Single crystal Er : YAG fibers with tailored refractive index profiles.

Erbium-doped yttrium aluminum garnet (Er:YAG) rods were inserted inside undoped tubes and grown into single-crystal fibers of a diameter of 300 μm using the laser-heated pedestal growth technique. Growth at various rates resulted in radially graded distributions of Er dopant ions, as observed using laser-induced fluorescence imaging. Profiles of the refractive index were measured using cross-sectional reflectometry in a microscope.

Oronasal distribution of ventilation at different ages.

The route of breathing, oral or nasal, is a determinant of the doses of inhaled pollutants delivered to target sites in the upper and lower respiratory tracts. We measured partitioning of ventilation, using a divided oronasal mask during a submaximal exercise test, in 37 male and female subjects who ranged in age from 7 to 72 y. The following four patterns of breathing were evident during exercise: (1) nasal only (13.

Cross-training between cycling and running in untrained females.

Objective: The purpose of the study was to evaluate the cross-training response between running and cycling in untrained females.

Experimental Design: The following study involved a pretest, post-test, 3 x 3 factorial design.

Setting: Training (4 days-week-1, 10 weeks, 70-80% heart rate reserve) occurred at the Center for Exercise and Applied Human Physiology.

Pre-exercise glycerol hydration improves cycling endurance time.

The effects of glycerol ingestion (GEH) on hydration and subsequent cycle ergometer submaximal load exercise were examined in well conditioned subjects. We hypothesized that GEH would reduce physiologic strain and increase endurance. The purpose of Study I (n = 11) was to determine if pre-exercise GEH (1.

Hemodynamic effects of nasal and face mask continuous positive airway pressure.

Studies of the hemodynamic effects of nasal continuous positive airway pressure (n-CPAP) in normal subjects have had conflicting results. The largest study (n = 19) found no effect of up to 15 cm H2O on heart rate (HR), cardiac stroke volume (SV), or cardiac index. We hypothesized that n-CPAP, by increasing intrathoracic pressure, should decrease SV and cardiac output (CO) in a dose-dependent fashion in normal subjects.