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The successful development of nuclear power reactors that are economically competitive with other sources of energy has led us to believe that more economical reactors will be developed. But, in developing the next generation of reactors, a new set of problems must be overcome. One of the most important of these is that of the embrittlement of the structural materials at high temperatures as a result of the intense neutron fields in these advanced systems. The radiation-induced embrittlement at high temperatures is probably associated with helium produced in the materials due to (n,α) reactions with the metal, and in some alloys radiation-induced precipitation of compounds within the alloy may also play a role. We believe that the most serious longterm problem is the generation of helium. Our current understanding of the mechanism by which this radiation damage is produced has allowed us to effect some improvement in the behavior of conventionally produced structural alloys, through minor modifications of the normal working and annealing processes used in their manufacture. However, we may find that new alloys will have to be developed to withstand the service conditions in future nuclear power reactors.

Lipoprotein lipase activity has been measured in both pre- and post-heparin plasma samples from 6 patients with Primary Type IV hyperlipoproteinaemia and from 6 normal subjects. Post-heparin lipoprotein lipase activity was of the same order in plasma from both groups. Appreciable activity was, however, noted in plasma collected from the Type IV patients prior to administration of heparin. Lipase activity was minimal in such samples from normal individuals.

A long-range view of world needs — considering such factors as population expansion, food and energy requirements, natural resources, and the rise in standard of living — indicates that the technical manpower shortage is here to stay.