Plasma alkaline phosphatase assay: interconversion of results by two methods

Two methods for measuring plasma alkaline phosphatase activity are compared: one makes use of phenyl phosphate, carbonate-bicarbonate buffer, and continuous-flow methodology; the other of p-nitrophenyl phosphate, diethanolamine buffer, and reaction-rate analysis. Results by the methods correlate well (r = 0.98) over a wide range of values (up to 10-fold the upper limit of normal). A factor can therefore be applied to convert results by one method into those that would be obtained by the other. The possibility that the presence of different proportions of isoenzymes in the plasma will affect this factor is considered. We have used the new method, with a conversion factor, as the routine method of alkaline phosphatase measurement in a clinical chemistry laboratory, with no problems.     

Observed and self-reported seat belt wearing as related to prior traffic accidents and convictions

During the summer of 1987, 10,000 color-coded mailback questionnaires that identified belted and unbelted North Carolina drivers were handed out at the 72 sites that constitute the probability sample for determining the statewide belt use rate in North Carolina. By obtaining identifying information to determine the winner of a $500 prize from among the 5,074 respondents, police-reported traffic accident and conviction records from the North Carolina driver history file were linked to the belted and unbelted respondents. Analyses found that drivers who had been observed not wearing seat belts had 35% more accidents and 69% more convictions than did belted drivers in the previous four-year period. Similar findings were obtained from self-reported belt use.     

A solution of the neutron diffusion equation for a hemisphere containing a uniform source

An analytic solution of the diffusion equation for a hemisphere of fissile or non-fissile material is presented which contains a spatially uniform neutron source. Numerical results are given for the flux distribution for one-speed fast neutrons in ²³⁵U and also for a non-fissile element of similar scattering properties. We use these results to check the accuracy of the finite element code EVENT. The procedure is also developed for multigroup calculations. In an Appendix we outline the procedure required when the hemisphere contains a source and is also irradiated by an external current of neutrons.     

Survival in neonatal biventricular repair of left-sided cardiac obstructive lesions associated with hypoplastic left ventricle

Patients with left ventricular hypoplasia and left-sided heart obstructive lesions other than critical aortic stenosis may be inappropriately subjected to single ventricular repair because their assessment is based on faulty qualitative evaluations or on quantitative methods developed for critical aortic stenosis. Patients with left ventricular hypoplasia and left-sided heart obstructions other than critical aortic stenosis successfully underwent biventricular repair despite "failing" to pass established criteria for critical aortic stenosis.     

Polynitrocubanes: Advanced High‐Density,High‐Energy Materials

More powerful and less shock‐sensitive explosives are continually being sought for both military and commercial use. Here the qualities a potential candidate must possess to make a good explosive are detailed, and the synthesis of octanitrocubane—a very promising candidate—is described. The physical properties of the nitrocubanes synthesized are also summarized and a proposal for the future is made.