Atomic transition probabilities for allowed and forbidden lines of Ba I and Ba II are tabulated, based on a critical evaluation of recent literature sources. The data are presented in multiplet format and are ordered by increasing excitation energies.

An evaluation of the reproducibility and accuracy of the NMR human blood test for cancer described by Fossel, E. T., Carr, J. M. and McDonagh, J., (New England Journal of Medicine 315, 1369-1376) in 1986 has been conducted jointly at the National Cancer Institute-Frederick Cancer Research Facility, Frederick, MD (NCI-FCRF) and the National Research Council, Ottawa, Canada (NRC). The influences on the test of the following were studied: (a) subject fasting; (b) sample collection, storage and handling; (c) use of plasma or serum; (d) variations of test results from the same individual with time; (e) NMR observation parameters including field strength and temperature; and (f) variations in obtaining the Fossel Index (FI) (a number defined by Fossel and co-workers as the average of the widths at half height of the regions in the NMR spectrum of human plasma at 1.3 and 0.88 ppm) by different people from the same plotted spectrum. This test was found to be reproducible but not accurate for screening a general asymptomatic population. The accuracy is defined in terms of the sensitivity, specificity, and predictive values of the test. The accuracy of the test results from our laboratories is compared with the accuracies from other laboratories including Fossel's. The correlation of the Fossel Index with total triglyceride content in the serum has been confirmed by analysing blood components using the following technologies: KBr density gradient centrifugation, high resolution agarose gel electrophoresis, high performance gel permeation chromatography, and chemical analysis.

The radiometric calibration program carried out by the vacuum ultraviolet radiometry group in the Atomic and Plasma Radiation Division of the National Bureau of Standards is presented in brief. Descriptions are given of the primary standards, which are the hydrogen arc and the blackbody line arc, and the secondary standards, which are the argon mini- and maxi-arcs and the deuterium arc lamp. The calibration methods involving both spectral radiance and irradiance are then discussed along with their uncertainties. Finally, the calibration services are delineated in an appendix .

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A source which produces a rather uniform distribution of spectral lines over the wavelength range from 115 to ~350 nm is being investigated as a secondary radiometric standard for use in space. This source is a sealed lamp with a hollow cathode of platinum and a fill gas of neon. A version of this lamp has already been flown in space but only as a wavelength standard. The following properties were studied: warmup time, stability, emission as a function of current, repeatability, spatial characteristics, impurities, angular dependence, long term behavior, and radiance.