Suppose that a finite group G admits a Frobenius group of automorphisms FH of coprime order with cyclic kernel F and complement H such that the fixed point subgroup CG(H) of the complement is nilpotent of class c. It is proved that G has a nilpotent characteristic subgroup of index bounded in terms of c, |CG(F )|, and |F | whose nilpotency class is bounded in terms of c and |H| only. This gener...

The ability of antibodies in bloodmeals of mice and hamsters immunized with Leishmania major subcellular fractions and sandfly (Phlebotomus duboscqi) gut antigens to inhibit development of L. major in its vector P. duboscqi was examined. Antibodies from animals immunized with either L. major subcellular fractions alone or sandfly gut antigen alone were not very effective in inhibiting developme...

A 2-cell embedding of a graph in an orientable closed surface is called regular if its automorphism group acts regularly on arcs of the embedded graph. The aim of this and of the associated consecutive paper is to give a classification of regular embeddings of complete bipartite graphs Kn,n, where n = 2. The method involves groups G which factorise as a product XY of two cyclic groups of order ...

Glossina morsitans were infected with two cloned stocks of T. congolense. The proboscides, foreguts and midguts of infected flies were then used as sources of trypanosomes in vitro at 28 degrees C in the presence of bovine dermal collagen explants. Cultures were established in which trypanosomes differentiated into adhering colonies of epimastigote forms which could then be maintained and subcu...