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A British researcher and a barrister argue the need for clarification of the role of genetic parents in the determination of the use made of fertilized embryos in research and medical practice.
Nuclear-pumped X-ray laser weapons are constrained to have an output beam divergence that is at least as great as a certain minimum value. Because this value is large, such weapons used for ballistic missile defence will require disturbingly high megatonnages in space: for example, a total of ≥ 73 megatons within range of 1,000 attacking missiles, with individual warheads up to 3.7 megatons or higher.
In immunology, abstract concepts are being made tangible by molecular structures. One new development shows that protein structure can evolve without changing common architecture.
