Threshold photodetachment in a repulsive potential.

We report on the first experimental observation of a new threshold behavior observed in the 5(2)G partial channel in photodetachment of K(-). It arises from the repulsive polarization interaction between the detached electron and the residual K(5(2)G) atom, which has a large negative dipole polarizability. In order to account for the observation in the K(5(2)G) channel, we have developed a semiclassical model that predicts an exponential energy dependence for the cross section.

Electron rescattering in above-threshold photodetachment of negative ions.

We present experimental and theoretical results on photodetachment of Br(-) and F(-) in a strong infrared laser field. The observed photoelectron spectra of Br(-) exhibit a high-energy plateau along the laser polarization direction, which is identified as being due to the rescattering effect. The shape and the extension of the plateau is found to be influenced by the depletion of negative ions during the interaction with the laser pulse.

Lung pathology in high-altitude pulmonary edema.

Autopsy findings in 10 cases of high-altitude pulmonary edema have been collected from published articles and personal observations. All cases were males with a mean age of 37 years (22-62). The altitude of occurrence was from 8400 to 17 500 feet.

Osteitis deformans (Paget's disease) and calcific disease of the heart valves.

The prevalence of calcific aortic valve stenosis in Paget's disease (osteitis deformans) was investigated by reviewing autopsy data of severe cases (> or = 75% involvement of > or = 3 major bones, the femur, tibia, skull, and pelvis) and moderate cases (> or = 75% involvement of only 1 or 2 major bones) of Paget's disease. Comparisons were made with normal age-matched controls. Aortic stenosis (AS) was present in 24% of 27 autopsies of severe Paget's disease compared with 3.