41.   Although the viscous sub-layer is very thin, a substantial fraction of the total mean velocity change across the boundary layer occurs within it.

42.   Although the number of steps is infinite, the whole sequence occurs within a finite range of the input variable, in our case the voltage.

43.   He pursued not only economies of scale but also reductions in the time occupied by movements which occurred within establishments so that labour could be used efficiently.

44.   The training is of recording which sub-patterns occur or which patterns occur within the tuple.

45.   Since much of the pathogenic effect occurs within the prepatent period, the faecal egg count may be very low.

46.   Since the acute disease occurs within the prepatent period, eggs of Oesophagostomum spp. are not usually present in the faeces.

47.   This breakpoint probably occurs within a large block of simple sequence satellite III DNA located close to the centromere.

48.   Three separate incidents apparently occurred within a fortnight of the start of this month including one in which a vial of radio-active substance was spilt.

49.   Although the fusion of ordinary hydrogen nuclei into helium atoms occurs within the Sun, pure hydrogen fusion would be very difficult to achieve on Earth.

50.   Analysts believe that decision should occur within a week.