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β thalassaemia is defined as a group of heterogeneous anaemias in which the β globin peptide synthesis is either absent or reduced by 30% or more. It is the world's most widespread autosomal recessive single gene disorder and represents a major health problem. More than 200 million individuals world-wide carry the β thalassaemia gene with an estimated 75,000 thousands of affected individuals born annually. Because of this β thalassaemia has attracted a great deal of research interest both at the molecular and clinical levels, which has led to the understanding of the complex molecular pathogenesis. Recent clinical management has improved and increased the life expectancy of affected individuals, however, the treatment required is very expensive and unsatisfactory. Therefore, the aim is to control the incidence of the disorder through the provision of carrier detection and prenatal diagnosis. Although prenatal diagnosis has reduced the number of β thalassaemia births, potential risks to the fetus have been associated with the available procedures. Furthermore, pregnancy termination is still unacceptable for many families, and couples at risk are looking for a safer, less emotionally traumatic way to have normal offspring. An alternative is offered by preimplantation genetic diagnosis carried out on the third day after in vitro fertilisation. With the application of nested PCR, amplification of the minute amount of DNA in a single cell has become possible and DNA analysis of single gene disorders for preimplantation diagnosis can be achieved. To enable preimplantation diagnosis of β thalassaemia by direct detection of mutant β globin genes at the single cell level nested PCR and silver stained single stranded conformation polymorphism (SSCP) analysis were employed. However, two main problems with single cell PCR, contamination and allele specific amplification failure in addition to mosaicism can lead to misdiagnosis and the transfer of affected embryos. In this study, the reduction of allele specific amplification failure by the use of SDS/proteinsae K as a lysis buffer, and the application of fluorescence based PCR to reduce the incidence of contamination which becomes apparent when reamplification is done, are reported. Furthermore, this study has also focused on optimising DNA amplification procedures using standard or quantitative multiplex fluorescent PCR in single cells for the detection of mosaicism and age related trisomy 21 along with specific diagnosis of single gene disorder diagnosis and developing mutation analysis techniques such as fluorescent SSCP and automated fluorescent DGGE for either early prenatal diagnosis using transcervical cells or preimplantation diagnosis. Finally, the first step of applying any prevention program for haemoglobinopathies is the identification of mutations within the β globin gene. The molecular characterisation of β thalassaemia has been studied in samples from Jordan and Egypt to facilitate screening and prenatal programmes based on DNA methodology.

The operation of multiple reservoir systems for sometimes conflicting purposes can be a complex process because of the involvement of a large number of decision variables and constraints. Dynamic programming (DP) has long been recognised as a powerful approach in the analysis of water resource systems. The usefulness of DP for multi-reservoir systems is, however, limited by the huge demand that it can induce on computational resources. Many forms of DP have been developed to alleviate the problem of dimensionality with varying degrees of success but no general algorithm exists. This thesis describes the development and application of Genetic Algorithms (GA) for the optimisation of multi-reservoir systems. The GA approach is validated through applications to a number of problems with known solutions. Several alternative formulations of a GA for reservoir systems are evaluated using the four-reservoir problem. This has been done with a view to presenting fundamental guidelines for implementation of the approach to practical problems. Alternative representation, selection, crossover, and mutation schemes are considered. The most promising GA approach comprises real-value coding, tournament selection, uniform crossover, and modified uniform mutation. A non-linear four-reservoir problem was also solved, along with a problem with extended time horizons. A more complex ten-reservoir problem was also successfully solved. The practicality of the developed GA approach in the determination of optimal reservoir operating rules is considered through application to a reservoir system in Indonesia. Optimal operating rules have been derived for the existing development situation in the basin, and also for two future water resource development scenarios using the critical period hydrology. A comparison of the GA results with those produced by Discrete Differential DP is also presented. The application of GA approach to real time operations with stochastically generated inflows is also demonstrated for a Lake system in Uganda. A methodology for forecasting reliable power that can be produced over different durations of time has also been developed using a GA. For the problems considered in this study, the GA solutions are very close to the optimum. The results demonstrate that the approach is robust and is easily applied to complex systems. It has potential as an alternative to stochastic DP approaches.

Fins stabilisers are devices which are fitted to the hull of a ship and utilised to ameliorate its rolling motions. They apply a regulated moment about the ship's axis of roll in order to oppose the sea induced disturbances. Recognising their unsurpassed performance, the Royal Navy, since the 1950's, equips all its vessels with fin stabilisers. It can be shown that the rudders, in vessels of appropriate size, also have the potential to be harnessed as roll stabilisers Rudder Roll Stabilisation (RRS) without degrading the ship's course-keeping. Thus creating a more stable platform for the human operators and equipment. The reported success of RRS imparted an impetus to the Royal Navy to initiate this study. The objectives are to ascertain whether RRS is possible without rudder modifications and to establish whether enhanced levels of stabilisation would accrue if the fins and RRS were operated in congress. The advantages in this novel approach being: avoidance of redesign and refit of rudders, three modes of operation (fins alone, RRS alone and combined RRS and fins), reduced fin activity and by implication self-generated noise, and amenability to be retrofitted by simple alteration of any existing ship's autopilot software. The study initially examined the mathematical models of the ship dynamics, defining deficiencies and evaluating sources of uncertainty. It was postulated that the dual purpose of the rudder can be separated into non-interacting frequency channels for controller design purposes. An integrated design methodology is adopted to the roll stabilisation problem. Investigating the capabilities of the rudder servomechanism, a new scheme, the Anti-Saturation Algorithm (ASA) was proposed which can eliminate slew rate saturation. Application of the ASA is generic to any servomechanism. The effects of lateral accelerations of the ship on human operators was examined. This resulted in an unique contribution to the Lateral Force Estimator problem in terms of generating time domain models and defining the limitations of the applicability of a control design strategy. Linear Quadratic Guassian and two types of classical controllers were constructed for the RRS and fins. A novel application of linear robust control theory to the ship roll stabilisation problem resulted in H . controllers whose performance was superior to the other design methods. This required the development of weight functions and the identification and quantification of possible sources of uncertainty. The structured singular value utilised this information to give comparable measures of robustness. The sea trials conducted represent the first experience of the integrated ship roll stabilisation approach. Experimental results are detailed. These afforded an invaluable opportunity to validate the software employed to predict ship motion. The data generated from the sea trials concurs with the simulations data in predicting that enhanced levels of roll stabilisation are possible without any modification to the rudder system. They also confirm that when the RRS is acting in congress with the fin stabilisers the activity of both actuators diminishes.

Several historical and recent reports have implicated mycobacteria or autoantigens cross-reactive with mycobacteria in the aetiology of rheumatoid arthritis (RA). Thus adjuvant arthritis can be transferred to naive rats with a T cell clone responsive to the mycobacterial 65 kDa heat shock protein (hsp65). Moreover agalactosyl IgG [Gal(O)], of which the oligosaccharides lack terminal galactose and terminate in N-acetylglucosamine (GlcNAc), occurs with increased frequency in RA and some mycobacterial infections. The cell walls of bacteria including mycobacteria are rich in terminal GlcNAc and the hsp65 is one of the immunodominant antigens of mycobacteria. The present study was undertaken to establish whether GlcNAc and/or hsp65-directed autoimmunity could occur in RA. Using a monoclonal antibody (mAb) which binds to terminal GlcNAc of Gal(O) the presence of large quantities of immunoreactive GlcNAc has been demonstrated in the joints of RA patients. It was also discovered that a subset of monocytes from both RA and normal donors transiently expresses membrane GlcNAc in culture. Affinity-purified anti-GlcNAc from both pooled normal and RA sera binds to IgG heavy chains on western blots. A murine mAb raised against mycobacterial antigen and a rabbit polyclonal antibody to hamster hsp65 were used to document the presence of a major band of around 65 kDa in synovial fluid (SF) from inflamed joints and immune complexes from RA patients. This protein was thought to be the human homologue of the mycobacterial hsp65. However, this molecule is about 7 kDa larger than the affinity-purified hsp65 from human placenta and it appeared unlikely that this molecule is of bacterial origin. This observation therefore casts doubt on several earlier reports where anti-mycobacterial antibodies were used to show increased expression of hsp65 in rheumatoid joints. The latter antibodies bind to several different components of human tissue and were not selected for specificity to human tissue. Therefore, mAbs were made to the human hsp and it has been shown that the major band at 65 kDa in SF is not the human homologue of the bacterial hsp65. Human hsp is present in the joint but at very low concentration and in SDS PAGE runs at about 58 kDa. Moreover, the previous reports showing increased expression of the hsp in joint tissues are inaccurate. First, it is clear that the presence of the hsp in rheumatoid tissues is not RA specific and secondly the distribution is also rather different from that described using the anti-mycobacterial antibodies. The levels of IgA and IgG antibodies to mycobacterial hsp65 are raised in RA sera and at least some of these IgG antibodies appeared to be autoantibodies. Moreover in RA SF a significant rise in the levels of IgA and IgG antibodies to the human hsp58 was found. There appears to be a correlation between raised levels of Gal(O) and antibody to hsp65 in mice, however no such correlation was found in RA sera or synovial fluid. Moreover, anti-GlcNAc antibody was not associated with raised Gal(O), and neither anti-GlcNAc nor antibody to hsp65 appear to lack galactose.