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To determine radiation doses incurred by inhaled thoron progeny, the Monte Carlo radon progeny lung dosimetry code IDEAL-DOSE was adapted to the inhalation of thoron progenies, comprising the alpha-emitting nuclides 216Po, 212Bi and 212Po. Dose calculations for defined exposure conditions yielded a dose conversion coefficient (DCC) of 4.6 mSv WLM(-1) or 94.2 nSv (Bq h m(-3))(-1) when compared with a DCC of 3.8 mSv WLM(-1) if based on the International Commission on Radiological Protection Human Respiratory Tract Model. Bronchial doses were computed for different thoron progenies exposure conditions measured in a Bavarian half-timbered house and in a thoron experimental house at the Helmholtz Zentrum München. DCCs ranged from 4.9 to 12.9 mSv WLM(-1), depending on particle size, unattached fraction and fractional activity concentrations. For exposure-specific indoor aerosol parameters, the thoron progeny DCC is smaller than the radon progeny DCC by about a factor of 2.

Measurements were made of the concentration of radioactivity in the breast milk of two patients: one following 100 MBq (2.7 mCi) 99Tcm-pertechnetate administration, and the other following administration of 550 MBq (15 mCi) 99Tcm-glucoheptonate. The fractional activity concentrations in the former case were about two orders of magnitude greater than in the latter and the effective half lives of secretion were 3 and 4 h, respectively. An infant breast fed without interruption would have ingested 5.2 and 0.055% of the 99Tcm administered with pertechnetate and with glucoheptonate, respectively. The former fractional ingestion was compatible with the larger value expected following pertechnetate injection without perchlorate pretreatment, and would have produced an effective dose equivalent to the infant of 1.5 mSV. An interruption to feeding of 12 h would reduce this dose to 0.2 mSV. It was concluded that breast feeding need not be interrupted after injection of 99Tcm-glucoheptonate other than for a short period of reassurance.

At the present moment the question whether or not there is a state of “all or nothing” activity in reflex arcs seems to be raised, and it is one of importance to the future of investigation of the functions of the nervous system. Of the two views which may be held regarding the manner of the activity of reflex arcs one is that in which it is supposed that the efferent neurone may react with different degrees of intensity in different reflex activities, and that the afferent neurones may play with different degrees of intensity upon efferent neurones or upon interposed neurones.

The catalytic activity of the γ-alumina surface has been investigated using infra-red spectroscopy and interpreted in terms of strong and weak Bronsted-acid sites and Lewis-acid sites. Doping of the γ-alumina with NaOH was used to eliminate Bronsted-acid sites. The influence of the two types of sites upon catalytic activity and selectivity was shown with studies of the simultaneous dehydration and dehydrogenation of 3-pentanol on pure γ-alumina or on several doped aluminas of varying NaOH content. Although the fractional activity of the weak Bronsted-acid sites is greater than that for the Lewis-acid sites, the differences in catalytic behaviour are considerably larger and are attributed to reduced accessibility of the Lewis-acid sites. The selectivity exhibited towards the two reactions was shifted from dehydration to dehydrogenation by eliminating Bronsted-acid sites.