Reasons for tooth loss is a crude index o f the dental health of a community, and was determined in a sample o f 600 Blacks on the Witwatersrand. Dental caries with or with­ out concurrent pathology was responsible for 67 per cent of tooth loss, periodontal disease for 19 per cent, trauma for 5 per cent, impacted teeth for 3 per cent and prosthetic reasons for 2 per cent. Dental caries was the ...

The dual theory describing the 4D Coulomb gas of point-like magnetically charged objects, which confines closed electric strings, is considered. The respective generalization of the theory of confining strings to confining membranes is further constructed. The same is done for the analogous SU(3)-inspired model. We then consider a combined model which confines both electric charges and closed s...

1. The sera of 80 per cent of the rabbits intravenously inoculated with fixed amounts of heat-killed pneumococci contained agglutinins and all showed protective antibodies. 2. The sera of 60 per cent of the intraperitoneally inoculated rabbits contained agglutinins and all showed protective antibodies. 3. The sera of 33 per cent of the intramuscularly inoculated rabbits contained agglutinins an...