Coherent transient data-rate conversion and data transformation.

Temporal compressions of optical pulses and pulse trains have been performed by the photon-echo process in Tm-doped YAG at 793 nm. Single-pulse temporal compression by almost a factor of 500 from 10 micros to 22 ns and pulse train compression by a factor of 14 from 5micros to 350 ns with a high-speed frequency-tunable external-cavity diode laser are demonstrated. It is suspected that significantly higher compression could be obtained by improved control of the laser frequency and laser frequency chirps.

Long-time-storage mechanism for Tm:YAG in a magnetic field.

We obtained a long-time-storage mechanism for spectral features in thulium ions doped into YAG by applying a magnetic field that splits the electronic ground state. We show experimentally that the storage time can be more than 30 s, which is 3 orders of magnitude longer than that of the metastable state that normally is used for information storage in this material. Level splitting and storage lifetimes for various magnetic field strengths of as much as 5 T were investigated.

Early and late results of controlled ventilation in flail chest.

From 1967 through 1974, a consecutive series of 35 patients with flail chest were treated with intermittent positive-pressure breathing (IPPB). The controlled ventilation contributed to stabilization of the thoracic cage in a favorable position for healing of the fractures. Surgical stabilization of the chest was not attempted in any of the cases.

Respiratory function in esophageal hiatus hernia. I. Spirometry, gas distribution, and arterial blood gases.

As a part of a preoperative investigation, spirometry and blood gas tensions were studied in 64 subjects with X-ray-verified hiatus hernia (34 sliding, 22 mixed, and 8 of paraesophageal variety). According to the transverse diameter of the hernia. They were divided into 3 groups, small (2-5.

Fractures of the scaphoid.

Fracture of the scaphoid is the most common injury of the carpus. Inadequate treatment frequently leads to non-union, which causes pain and serious disability. In the present study 134 scaphoid fractures treated during the period 1961-70 are reviewed.