RESUMEN
Enhancements to the JET poloidally scanning spectrometers are presented, which will aid the exploitation of the recently installed ITER-like wall in JET. They include the installation of visible filter∕photomultiplier tube assemblies and spectrometers and the replacement of large rotating mirrors in the JET vacuum with small oscillating mirrors outside. The upgrade has resulted in a more robust and reliable diagnostic than before, which is described. Drifts in the mirror angle reconstructed from quadrature encoder signals are found, a reference signal being required. The use of the small scanning mirrors necessitated the inclusion of focusing mirrors to maintain throughput into the vacuum ultraviolet spectrometers. The mirror design has taken account of the extreme sensitivity of the focusing to the grazing angle of incidence, an aspect of importance in the design of grazing incidence focusing components on future machines, such as ITER. The visible system has been absolutely calibrated using an in-vessel light source.
RESUMEN
Twenty cases of varicella occurred in patients or siblings of patients in a 41-day period in a children's hospital. Most cases were among oncology patients, with transmission occurring in both the inpatient and outpatient areas. One patient died after visceral dissemination of varicella. Neither pooled immunoglobulin nor zoster immune plasma was effective in preventing clinical varicella, although zoster immune plasma appeared to ameliorate the illness. Recommended control measures included strict isolation or discharge of infected patients, and respiratory isolation or discharge of exposed susceptibles. Although apparently too late to be effective in this outbreak, similar measures are warranted should nosocomial outbreaks of varicella occur elsewhere.