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This thesis is studying nitric oxide (NO) as a fundamental basis for health and disease and investigating as well as modifying its properties for therapeutic purposes. In the UK, nearly 3.5 million people have angina symptoms or have had a myocardial infarction (MI), or both. The mainstay treatment for reducing the symptoms of angina and long-term risk of MI in patients with heart disease is stent implantation in the diseased coronary artery. While this procedure has revolutionised treatment, the incidence of secondary events remains a concern. These repeat events are thought to be due, in part, to an increased inflammatory state that predisposes to continued enhanced platelet reactivity, endothelial dysfunction, and ultimately restenosis of the stented artery. In addition, CVD in general including atherosclerotic disease occurs at a lower incidence in premenopausal females compared with age-matched males. There has been considerable interest in why this might be the case but whether sex differences in inflammation underlie these differences is uncertain. Greater understanding of the role of inflammation and strategies that might selectively reduce inflammation within the CVD setting may offer novel approaches to therapeutics. Thus, I prospectively investigated whether inflammation and components of the inflammatory response are altered in females compared with males using two healthy volunteer studies. In the first study, I assessed systemic inflammatory markers and vascular function using brachial artery flow-mediated dilation (FMD). Typhoid vaccine induced mild systemic inflammation at 8 hours, reflected by increased white cell count in both sexes. Systemic inflammation in turn caused a decrease in FMD in males, but an increase in females, at 8 hours. To investigate the differences in inflammatory responses between the sexes further in a separate study, I measured inflammatory exudate mediators and cellular recruitment in cantharidin-induced skin blisters. At 24 hours, cantharidin formed blisters of similar volume in both sexes; however, at 72 hours, blisters had only resolved in females. The activation state of all major leukocytes was lower in blisters of females, which was associated with enhanced levels of the resolving lipids. Together these findings suggest that in females, resolution of inflammation is accelerated compared with males, and that within the cardiovascular system this is likely to result in improved vascular function. The second part of my thesis studies was focussed on using the techniques established in the healthy volunteer studies to investigate whether a once a day inorganic nitrate (NO3-) administration might, through modification of inflammatory pathways, favourably modulate platelet reactivity and endothelial function leading to a decrease in restenosis. This was conducted in the form of the NITRATE-OCT study, which is a phase II trial enrolling 246 patients with stable angina due to have elective stent implantation. Patients have been randomised to receive 6 months of a once a day dose of either NO3--rich beetroot juice or NO3--deplete beetroot juice (placebo) before their procedure. The primary outcome is reduction of in-stent late loss assessed by quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 6 months. Thus far, we have baseline demographic data for 200 patients in total and the study is still ongoing to ensure the investigators remain blinded. At baseline there were no significant differences in demographic or procedural characteristics between the two groups.

Foreign direct investment in the mining and oil industries is invariably fostered through the signing of concession agreements between the host State and the investor. Such concessions may contain fiscal incentives, to encourage the flow of FDI. However, such concessions are also susceptible to alteration by the host State, once the investment has been sunk. This may include increasing taxes or outright nationalization. To avert this, investors will often insist on the insertion of stabilization clauses. These clauses constitute an undertaking on the part of the host State, that they will not take any administrative or legislative action that would adversely affect the rights of the investor. Such clauses are well recognized by arbitral tribunals and the unilateral abrogation of these clauses, will have pecuniary consequences. Not only will the host State have to pay damnum emergens but also lucrum cessans as part of the compensation package to the investor. Such a position promotes efficiency as per the efficient breach theory, by discouraging the State from terminating concession agreements unless they will make some money, even after compensating the investor for lost future profits. However, this ultimately renders stabilization clauses inflexible because they preclude the host State from pursuing legitimate public functions. Such a position, necessitates some form of contractual flexibility. However, the legitimate expectations of the investor also ought to the protected. The means of achieving this balance is by the inserting renegotiation clauses in the concession agreements.

Conflicts bring deaths and disabilities, population displacements, destruction of properties and changes to societies. Conflicts also devastate the economy, health, education and institutions. Within this context post conflict reconstruction contributes to overcome the legacies of conflict through reconstructing the enabling conditions for a functioning peacetime society. Post conflict reconstruction involves a wide range of interventions needed to reactivate the development process that has been disrupted by the conflict. With regard to the post conflict interventions, post conflict housing reconstruction plays a vital role in establishing the development and peace in conflict affected countries. Despite its importance, the success of post conflict housing reconstruction is hindered by a number of problems such as lack of community participation, lack of strategies to address the challenges faced by vulnerable people, lack of consideration of local and cultural conditions, lack of consideration of socio-economic conditions of affected people, poor technical oversight and a lack of security of land tenure. Consequently these problems have caused dissatisfaction resulting in some people to remodel or abandon the houses. Furthermore, it has been revealed that the lack of consideration of housing needs in post conflict housing reconstruction has directly or indirectly given rise to most of these issues. Therefore addressing these needs would contribute to minimising the issues of post conflict housing reconstruction and adequate housing measures provide guidelines in such situations in addressing housing needs in post conflict housing reconstruction. However, the countries emerging from conflicts have different characteristics that add a different dimension to post conflict housing reconstruction. Accordingly, addressing housing needs cannot be considered in isolation without considering the challenges pose by the characteristics of the post conflict setting. In this context, there is a need to understand how these particular housing needs can be effectively addressed. Accordingly, this study addresses this eminent need by exploring how can the housing needs be effectively managed in post conflict housing reconstruction. As Sri Lanka’s long lasting conflict came to an end in 2009 leaving a legacy of immense damage to housing, post conflict housing reconstruction remains prominent within post conflict interventions in the country. Accordingly, Sri Lanka provides a sound basis for this study and hence the study is centred on it. Ontological and epistemological positions of this study led to subjectivism and interpretivism respectively. Grounded theory approach was used as the research strategy. While unstructured interviews were used as the primary data collection technique, interviews were supplemented by creative visual images. Interviews were also verified through a documents review. Grounded theory data analysis procedure was used to analyse the unstructured interviews. The study reveals the challenges, contributing factors and strategies in addressing housing needs in post conflict housing reconstruction. It also identifies the gaps in managing housing needs and recommendations to minimise such gaps in managing housing needs in post conflict housing reconstruction. Furthermore, the study develops a theoretical framework that presents the associated challenges, contributing factors, strategies, gaps and recommendations to minimise such gaps in managing accessibility, habitability, affordability, location, facilities, cultural consideration and security of land tenure in post conflict housing reconstruction. Key words: Conflict, Post conflict, Post conflict reconstruction, Post conflict housing reconstruction, Housing needs and Managing housing needs.

Bangladesh, where only 20% of the total population are connected to grid electricity, has a promising scope to utilise biomass for decentralised electricity generation. In this study, sustainable biomass electricity generation model was developed for the country, by combining tech no-econometric and optimisation modelling techniques. The developed model addresses the biomass generation and availability, feasible technologies, cost and efficiency correlations, economic plant size, plant economics and sensitivity, and environmental and social impacts. In 2003, the national total annual available biomass energy potential in Bangladesh varies from 183.848 to 223.776 TWh. The feasible technologies are: gasification based ICE-generator, anaerobic digestion based ICE-generator and direct combustion based steam turbine or Stirling engine-generator. Correlations of capital investment costs and overall conversion efficiencies with the plant electricity generating capacity have been developed. Direct combustion technology shows the highest electricity generation potential of 20.21 TWh/year; followed by gasification, of 14.30 TWh/year. Economic radius of biomass collection and size of the plants has been determined for maximum profitability. The biomass electricity plants economics have been estimated and compared with the diesel and dual-fuelled plants. Analysis shows that, anaerobic digestion and gasification-based electricity generation plants are economically feasible. Biomass electricity plant is highly sensitive to changes in biomass price, selling price of electricity, investment cost, plant lifetime, conversion efficiency and operating hours. The employment of the biomass electricity instead of diesel generator saves significant amount of the greenhouse gas emissions. It creates more employment than conventional and presents other socio-economic benefits as well. Due to the combination of electricity generation potential, promising economics and low greenhouse gas emissions; gasification-based biomass electricity plant is recommended for the country. Biomass availability and plant economics vary between districts to districts. Computer programmes have been developed for district wise biomass electricity plant analysis.

This dissertation discusses several different approaches towards a better understanding of enzyme mechanisms. After a brief introduction to enzyme catalysis there is a general review of acetal hydrolysis and previous investigations into the mechanism of glycoside hydrolysis catalysed by lysozyme. The third chapter describes studies towards the synthesis of a serine protease model. The remaining three chapters discuss investigations into the mechanism of lysozyme, through the use of substrate models, proton transfer models and a bifunctional catalysis model. After an introduction to the catalysis of peptide hydrolysis by the serine proteases, the design and studies towards the synthesis of an oxyanion hole model are described in Chapter 3. A collaborative project investigating different steric and electronic effects on acetal hydrolysis in lysozyme substrate models is presented in Chapter 4. After a brief overview of the conception and aims of the project, details of the synthesis of some of the models are given, and the results of kinetic analyses of all the model compounds are discussed. The study of ethers of salicyclic acids is described in Chapter 5. Although the aromatic system is not a good enzyme model these compounds were designed in order to investigate the efficiency of the intramolecular proton transfer catalysis and to determine whether the hydrolysis of relatively unreactive substrates could be catalysed. Two catalytic groups are involved in the mechanism of lysozyme. The final chapter details the design and synthesis of a model containing two functional groups positioned to attack an acetal carbon. Kinetic studies of the hydrolysis of the model and a discussion of the results obtained are presented.

The World Bank produces sample bidding documents for use by its member countries to prepare tender forms and contract conditions for Bankfinanced civil engineering construction contracts. The contract conditions provide for arbitration of disputes and parties to a contract may choose to submit to the International Centre for Settlement of Investment Disputes (ICSID) which was established by members of the World Bank for the settlement of investment disputes between states and nationals of other states. The objectives of the Thesis are to (i) examine the legality of generally submitting disputes in international civil engineering contracts to ICSID arbitration, (ii) provide an analysis of ICSID as an international arbitral institution and (iii) discuss the legal aspects of submission of disputes to ICSID arbitration in breach of the Convention that established ICSID. Chapters One, Two and Three are devoted to describing the importance of civil engineering works to economic growth and arbitration as a method of resolution of disputes. An analysis is made of the fundamentals and complexity of the arbitral process and the interfacing between legal systems, national laws and international law in international arbitrations. Chapter Four traces the genesis of ICSID and Chapter Five examines critically the salient features of ICSID arbitration, which according to the Thesis are not all exclusive to ICSID arbitration. Chapters Six and Seven analyse in depth ICSID jurisdiction ratione personae and ratione materiae. Chapter Eight argues that disputes in freestanding international civil engineering contracts are not investment disputes and that submission to ICSID is in breach of the Convention. Chapters Nine and Ten discuss the legitimate role of ICSID in developing rules of international economic law and conclude by recommending that ICSID should not detract from that role by becoming just another arbitral institution in. the business of arbitration.

The purpose of this research is twofold - the first objective being to develop Markovian models that can be used to analyze the performance of the various medium access control protocols of slotted ring type local area networks.

The active magnetic bearing (AMB) is a relatively new technology in which the suspension forces are generated magnetically without any contact. Although there are many advantages of AMB technology over conventional bearing design, its major selling point is the claim of reduced maintenance and longer run times between mandatory shutdowns to replace worn or defective components. This claim is, however, somewhat diluted by the fact that the majority of industrial applications have relied upon anti-friction backup bearings. These backup bearings are, in the event of control system failure or limited operation during momentary overload conditions, essential for the protection of AMB rotor, stator and other stationery seals along the shaft. The increase in the number of critical path machinery using AMB technology has focused awareness and necessity for proper design of these auxiliary bearings to avoid additional unwanted down-time. In this research, the equations of equilibrium governing the dynamic response of a rotor-bearing system were formulated and then solved using an appropriate numerical algorithm capable of analyzing this non-linear system. An efficient transient response analysis program was developed for evaluation of shock loading, blade loss and rotor drop of active magnetic bearing machinery. This program can analytically predict the path of the rotor and the instantaneous loads acting on the backup bearings during rotor drop which would help in the design of more reliable backup bearings without evaluating them experimentally. Parameter variation study was conducted analytically to observe the influence of some important factors on the dynamics of rotor drop phenomenon. The results from this program have also been compared to the experimental data obtained from the Virginia Tech Rotor Dynamics Laboratory AMB Rotor Drop Test Rig.

Modern rice (Oryza sativa L.) varieties produce very high yields under high input and favorable environments. Limited work has been done to develop plant types suitable for less than optimal environments at moderate N management levels. The objectives of this study were: 1) to examine the relationship between the uptake of N and different leaf characteristics, sink size, and grain yield of three morphologically distinct rice varieties; 2) to examine the CO2 exchange rates (CER) of rice varieties in relation to light, N management, water use efficiencies (WUE), and N use efficiency (NUE): and 3) to determine characteristics of rice varieties that are associated with productive potentials under low N management levels. A greenhouse experiment was conducted in 1989 at Virginia Polytechnic Institute and State University, Blacksburg, VA and a field experiment was conducted in Sri Lanka at two locations in 1990. In the greenhouse experiment three varieties (a traditional, an intermediate, and a modem variety) were grown under four N management (rate and time) treatments: viz 1) a 0 N control, 2) 200 mg N kg⁻¹ of soil split into two applications, 3) 200 mg N kg⁻¹ of soil split into three applications, and 4) 400 mg N kg⁻¹> of soil split into three applications. Competitive use of fertilizer N for the development of either large leaf area or high leaf N content per unit leaf area (LNLA) varied with the rate and timing of N fertilizer application and rice variety. When N supply was limited and early N applications were restricted, the intermediate variety increased LNLA in the flag leaf with little increase in total leaf area of the plant. Specific leaf weight did not differ with N management except for the low value of the N control treatment. Increased N applications reduced stomatal density. Total stomatal number leaf⁻¹ varied little within cultivars indicating that N fertilization enables the leaf to increase leaf area and thereby disperses the fixed number of stomates. Carbon dioxide exchange rates were higher in the flag leaf than lower leaves and were directly correlated to LNLA.