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Like other field theories of physical interest, the moduli-space integrals of the non-linear two-dimensional 0(3) sigma model diverge. We show that in the one-instanton sector the imposition of a cut-off in the moduli-space leads to an unacceptable dependence of the Green’s function on the way that the field is split into the quantum piece and the classical background. This dependence may be isolated in a term which may be interpreted as an anomaly to the Ward Identity of the theory. The moduli-space divergence is associated with degeneration of the field configurations to those of another topological sector. Hence it is possible that by modifying the Green’s function in, say, the zero-instanton sector will be able to cancel the divergence in the one- instanton sector. We show that the Ward Identity anomaly in the one-instanton sector may be written in the zero-instanton sector at next to leading order in powers of h, and hence we explicitly calculate the Green's function modification. We have called the process of applying this modification "Topological Renormalisation". A central piece of the modification term is the instanton contribution to the Green's function of the model. This is obtained by using two new methods of calculating the determinant of the fluctuation operator. The application of Topological Renormalisation to other theories is also investigated.

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This study aimed to investigate the feasibility of using several genetic techniques for identification of sulphate-reducing bacteria. A group of eight type strains (seven of which were <I>Desolfovibrio</I>) were used as test group for every method except RSGP, for which an established set of oil field isolates was used. Ribotyping involves restriction fragment length polymorphism (RFLP) analysis of ribosomal RNA (rRNA) operons. Hybridisation of <I>Eco </I>RI-digested genomic DNA to a PCR-amplified (500 bp) rRNA gene product resulted in generation of discriminatory RFLP patterns for all but two of the eight test strains. Restriction digestion of PCR-amplified (1400 bp) rRNA gene products (PCR-robotyping) allowed differentiation between all eight strains for two of the seven enzymes tested. Random amplified polymorphic DNA (RAPD) analysis allows PCR-generation of distinct sets ("fingerprints") of amplification products from genomic DNA templates. Nine oligonucleotide decamers were tested as primers, two of which were found to generate discriminatory profiles for each of the eight type strains. Hybridisation of 32P-labelled RAPD products against genomic DNA from eleven sulphate-reducing strains was found to result in specific hybridisation of probes to their complementary genomic DNA. Reversal of the hybridisation procedure, using 32P-labelled genomic DNA against immobilised RAPD probes, was found to allow analysis of mixed genomic DNA samples in a single step. This reverse method is very similar in principle to RSGP, which allows analysis of mixed genomic DNA preparations by hybridisation against a master filter of genomic DNAs from a series of environmental bacterial standards. This study developed a method to allow quantitation of RSGP hybridisation signals, and went on to analyse biofilm samples from various locations in Western Canadian oil fields, resulting in identification of 21% (average) of each mixed DNA sample.

The purpose of this investigation was to study the thermoelectric effects in a single crystal of antimony at liquid-helium temperatures.

The purpose of this paper was to prove the equivalence of the following completeness axioms. This purpose was carried out by first defining an ordered field and developing some basic theorems relative to it, then proving that lim [(u+u)*]^n = z (where u is the multiplicative identity, z is the additive identity, and * indicates the multiplicative inverse of an element), and finally proving the equivalence of the five axioms.