1 Numerical Methods of Analysis in Engineering. Edited by L. E. Grinter, Macmillan Company, New York, 1949, chapter 4. s L. Fox, "Some improvements in the use of relaxation methods for the solution of ordinary and partial differential equations," Royal Soc, London, Proc, v. 190A, 1947, p. 31-59. ' L. Fox & J. C. P. Miller, "Table-making for large arguments. The exponential integral," MTAC, v. 4...

It has been known for some time that the root excretion of several species of Solanum stimulates the hatching of larvae from the cysts of the potato eelworm, Heterodera ro8tochien8i8 (Franklin, 1940). The isolation ofthe active principle in root excretion and the investigation of its chemical nature was first attempted, using the leachings from potato plants (Hurst, 1935, 1937), but the method ...

PG has been identified as a psychiatric disorder in its own right since 1980, and is included within the current DSM (DSM-IV TR; APA, 2000) as an Impulse Control Disorder. The recommendation to re-classify this disorder has been made as a result of the increasing body of literature which reveals a high degree of similarity between SUDS and PG in relation to diagnostic criteria, co-morbidities, ...

Chairman: J. R. Durig (USA; 1983-89); C. J. H. Schutte (RSA; 1989-93); J. E. Bertie (Canada; 1993-97); Secretary: H. A. Willis (UK, 1983-87); J. G. Grasselli (USA; 1987-89); J. F. Sullivan (USA; 1989-95); Titular Members: A. M. Bradshaw (FRG; 1983-91); R. D. Brown (Australia; 1987-93); B. G. Derendjaev (Russia; 1983-91); R. K. Harris (UK; 1989-93); A. M. Heyns (RSA; 1993-97); E. Hirota (Japan; ...

Acknowledgements The work presented in this thesis would not have been possible without the help and support of far more people than I can recognize in this space. First and foremost I would like to thank my family, especially my parents Lynn and Gene Edens, for all their guidance and continued support over the years. They have provided the foundation on which the person I am has been built. I ...

The 12-dimensional Coxeter-Todd lattice can be obtained by lifting the ternary Golay code to a code over the integers mod 9 and applying Construction A. Several recent papers have pointed out connections between codes over & and lattices [l], [3]. It is the a m of this correspondence to show that the Coxeter-Todd lattice K12 ([4], [5, ch. 4, sec. 91) can be obtained in a similar way from a code...

and analogous bounds are established here for odd lattices satisfying certain technical conditions (which are trivial for N=1 and 2). For N>1 in (V), lattices meeting the new bound are constructed that are analogous to the ``shorter'' and ``odd'' Leech lattices. These include an odd associate of the 16-dimensional Barnes Wall lattice and shorter and odd associates of the Coxeter Todd lattice. A...

Coset enumeration, based on the methods described by Todd and Coxeter, is one of the basic tools for investigating nitely presented groups. The process is not well understood, and various pathological presentations of, for example, the trivial group have been suggested as challenge problems. Here we consider one such family of presentations proposed by B.H. Neumann. We show that the problems ar...

We study algebraic K3 surfaces (defined over the complex number field) with a symplectic automorphism of prime order. In particular we consider the action of the automorphism on the second cohomology with integer coefficients (by a result of Nikulin this action is independent on the choice of the K3 surface). With the help of elliptic fibrations we determine the invariant sublattice and its per...

Coxeter groups have presentations 〈S : (st)st∀s, t ∈ S〉 where for all s, t ∈ S, mst ∈ {1, 2, . . . ,∞}, mst = mts and mst = 1 if and only if s = t. A fundamental question in the theory of Coxeter groups is: Given two such “Coxeter” presentations, do they present the same group? There are two known ways to change a Coxeter presentation, generally referred to as twisting and simplex exchange. We ...