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The thesis investigates to what extent the international right to health can generate standards for Health Technology Assessment (HTA) implementation and policies. HTA has been used as a multidisciplinary process to determine the broad impact and cost-effectiveness of new healthcare technologies and interventions in health systems under multiple levels of resource constraints. By exploring the relation of this process with State measures to promote access to health, this thesis proposes a human rights-based approach (HRBA) to HTA focused on controlling economic relations and ensuring favourable conditions for access to healthcare. The central point of analysis is how the premise of scarcity, which inspired procedural approaches in bioethics and right to health litigation studies, is not rigid and can be mitigated by State continuous efforts during HTA. The normative focus is on Article 2.1 of the International Covenant on Economic, Social and Cultural Rights, concerning fundamental principles of progressive realisation and maximum available resources. In this doctrinal analysis, the notion of resources is expanded so as to include State regulatory power at large to contain scarcity through laws alongside HTA decisions. Resources, in this interpretation, involve enabling affordable healthcare, obligations of international cooperation and State support to evidence-making and knowledge production that enhance HTA criteria. A case study in Brazil indicates how the procedural justice model is insufficient to guide State responses to scarcity. A documentary analysis suggests that policies and law can be in practice applied as prescribed by the international economic and social rights principles concerning resource mobilisation, which cannot be divorced from resource allocation in political deliberations. Therefore, an HRBA to HTA should not be read as merely procedural justice but should also impose obligations to address the causes of scarcity where possible before overdependence on rationing deliberations.

The manufacturing process of photovoltaic devices, such as solar cells, relies on the production of Transparent and Conductive Oxide (TCO) films. One of the techniques for creating these films is based on Aerosol-Assisted Chemical Vapour Deposition (AACVD). The AACVD process comprises the atomisation of a precursor solution into aerosol droplets, which are transported to a heated chamber for the synthesis of films such as the TCOs, as well as coatings, powders, composites and nanotubes. At present, AACVD has not been used as an industrial deposition technique. However, it has the potential to be scaled-up due to its versatility and the ease through which effective functional coatings can be deposited at a laboratory-scale. Computational simulations are pivotal to study the feasibility of such a scale-up. This thesis presents, therefore, an integrated model to support the AACVD process scale-up. The model is comprised of four stages: aerosol generation, transport, delivery and chemical deposition. The generation of aerosol is described by a distribution of droplet sizes, which is the input to a transport model that incorporates the impact of aerosol losses. The output distribution provides sufficient information to predict the amount and sizing of aerosol reaching the deposition site. Experimental validation has shown the model to be effective at predicting transport losses and droplet sizes. The delivery stage includes the solvent evaporation, accounting for uncertainties in the temperature profile of the deposition site. This is a key factor for the solvent evaporation, setting the precursors free to react and form the desired products. For the chemical deposition stage, reactions in the solid and gas phases were studied. The model presented is suitable for application on the scale of industrial processes and is also suitable for processes that rely on atomisation and transport of particles, for example, spray drying or cooling and fuel combustion. Lessons learned in modelling uncertainties and their impact on process scale-up motivated the research into formulation, modelling and solution methods for such applications. Therefore, as an additional contribution, this thesis introduces Uncertainty.jl, a modelling framework focused on the treatment of uncertainty.

This practice-based research, which consists of this dissertation, a portfolio of compositions, and a programming library for Python, explores the role played by metaphors and mental models in providing a framework for algorithmic composers to operate within. When working with algorithms, the composer approaches the act of music creation through an algorithmic lens which, in turn, can often suggest specific compositional ideas. To put it simply, in order to compose with algorithms, the composer must think algorithmically, which, in turn, affects how they conceive their musical ideas in the first place. We are shaped by our tools. This research argues that this algorithmic musical thinking is often realised with the aid of metaphors and mental models. These cognitive mechanisms are crucially important not only for algorithmic conceptualisation but also for their potential to suggest specific ways of organising and manipulating algorithmic ideas, directly influencing the final artwork. As such, this work presents a novel way of approaching algorithmic composition, one in which the composer is consciously designing specific (and possibly idiosyncratic) mental models. From this perspective, composition becomes an investigation of the potentials of these mental models, aligning itself with the notion that algorithmic music can serve as a form of exploration to reach musical results not entirely planned a priori. This approach is utilised throughout the accompanying portfolio of compositions, which is also analysed in this dissertation. The mental models employed in these compositions-particularly those involving musical repetition-are connected to a specific set of aesthetic concepts that underpins this research. The accompanying programming library, Auxjad, provides classes and functions written in Python that directly implement these specific mental models. This library is publicly available online under a permissive free software license, allowing other composers to adapt and incorporate its code into their own practices.

The resolution of imaging devices is ultimately limited by the diffraction of light. This limit can be circumvented by exploiting near-field phenomena, non-linearities of the sample or specific illumination schemes, which led to the recent explosion of optical super-resolution techniques. However, it would be desirable to reach the nanoscale in the most general way possible, with far-field linear imaging of uniformly illuminated samples. In the last few years, the answer to that came with the field of quantum-inspired super-resolution (QISR), where quantum metrological techniques were used to find novel measurement schemes that, beyond the conventional direct imaging of light, would achieve higher precisions. Interestingly, these ideas would always in some way or another involve transverse spatial modes of light. This thesis presents our work on the subject, with novel theoretical and experimental results. Firstly, we develop the traditional theory of QISR, with has mostly focused on either the estimation of separation of two point sources or on geometric moments of samples. Then, we introduce our own results on optical imaging of general distributions of point sources, in a step to take QISR from toy examples to real imaging scenarios. Secondly, we apply all the concepts studied on a experimental, proof-of-principle implementation of a QISR scheme dubbed Hermite-Gaussian Microscopy (HGM), which uses heterodyne detection with several Hermite-Gaussian modes as local oscillator in order to reconstruct the object sample and achieve super-resolution. We report the techniques necessary for the manipulation of spatial modes of light, as well as our results, where we demonstrated 2D imaging with twofold resolution enhancement beyond the diffraction limit.

Humankind is facing one of the most challenging periods in its short history on Planet Earth. These challenges have largely arisen as a result of climate change and the loss of tropical forests. Indeed, these challenges present two of the greatest environmental challenges of all time. Nevertheless, Brazil has recently adopted policies that have greatly reduced forest loss over the past decade or more. A strong combination of different policies and actors have made this achievement possible, and environmental law enforcement is thought to have played a key role. Therefore, the central questions for this thesis is to determine the influence of environmental law enforcement, mostly ground operations in the Brazilian Amazon region, on reducing deforestation, reshaping land use change, through livestock, agriculture and natural restoration, and the persistence of natural regeneration. First, I assess the influence of law enforcement on forest loss reduction through a spatial analysis at the municipality level. The results confirmed that law enforcement, along with other factors, is an important influence on reducing forest loss. However, law enforcement also has to tackle some administrative limitations, as a shift and modernization of the environmental police strategy is imperative to face the new challenges, and the appropriate implementation of the rural environmental registry policy will be crucial. Second, I explore the possible influence of law enforcement on reshaping land use change, focusing on annual crops, livestock and natural regeneration, using a difference-in-differences with an entropy balance approach at the municipality, private property and settlement levels. I have evaluated the priority municipality policy implemented in 2008 that led to an intensification of law enforcement on target municipalities. The results show an increased persistence of agriculture and clean pastures, as a substantial increase in natural regeneration occurs through abandonment, a reduction of dirty pastures, and suggests an influence of law enforcement on this land use dynamic. Annual crops, mostly soy, turned to be an agglomerated economy in the central area of Mato Grosso, while extensive pastures are more widespread with low levels of occupation and also as part of land speculation. Both activities are showing signs of intensification and land sparing, at least for natural regeneration. So, conservation policies based on law enforcement have contributed to the reshaping of land use systems in the Brazilian Amazon. Although certainly not alone, but in combination with other policies and initiatives. This study shows that law enforcement became a stronger component of farmers’ land use investments and decision-making processes. Thus, while pockets of illegality still prevail, environmental and land tenure law enforcement will be mandatory. Only with this will it be possible to ensure the effectiveness of a sustainable intensification, reduction in forest loss, and fulfil the role of spare lands for conservation, agriculture and ultimately achieve a balanced land use system. Third, I present results of the possible influence of law enforcement on the persistence of over 41,000 km2 of natural regeneration during the past 10 years of this study. This question has received much less attention than the others, and it is not clear what is driving this persistence of regeneration. Therefore, this thesis sought to investigate if this persistence could be a co-benefit of the environmental police actions against deforestation. The results suggest a positive effect of command and control on the persistence of natural regeneration. This observation has important implications for the Brazilian climate change policies and restoration commitments under the Paris Agreement. Furthermore, it could represent a substantial contribution to the global restoration targets established at CBD, Bonn Challenge and New York Declaration on Forests. I conclude where I started, with the conviction that is possible to balance conservation and production. The results of this thesis are encouraging and suggest the strong influence of law enforcement, as catalyst, on reshaping land use system dynamics towards intensification, forest loss reduction and increased natural regeneration persistence in the Brazilian Amazon region. However, it is also clear that this can be an unstable balance and any political and/or policy perturbations may cause big losses and quickly reverse the consistent advances seen during study period. So, the challenge ahead is to make this balance consistent and stable, and less vulnerable to perturbations.

For many, including the majority of the Supreme Court in the ADI 4650 case, war chest and dependence corruption apparently occurred in Brazil. This thesis investigates, through case studies, whether the appearance of those types of political finance corruption impacted the confidence we should have in the democratic integrity of antitrust legislation and its enforcement; and concludes that this confidence has been impaired, at least partially. Considering that, when it comes to political finance corruption, mere appearance is enough to justify regulatory reforms, the question that then arises is how the law of democracy should be framed to promote the appearance of electoral integrity. The thesis advances a proposal to foster the appearance that elections reflect a 'free formation of public opinion', and, in that sense, it argues that political finance and media regulation should adopt that as a paradigm. By arguing that legislation aimed to promote media access and impartiality of broadcast corporations during elections is not (and perhaps will never be) enough to satisfactorily diminish the influence of media economic power over elections in Brazil, the thesis proposes media regulation based on both democratic distribution and the power to impact public opinion. When it comes to the competition between political parties and their candidates, the thesis argues that vouchers could help to solve the controversy regarding the distribution of parties' public resources but that, in any event, caps should be introduced to prevent predominant influence on public opinion. The paradigm also provides an answer to the dilemma faced by judges whenever they must determine what level of illegal spending is sufficient to distort an election: under a Rawlsian account of democracy, if the illegal practice allowed the candidate to have more than 30% of total electoral spending, there is a presumption that it distorted the election - under a Schumpeterian perspective of democracy, that threshold could be adjusted to 50%.

Anaerobic digestion is a widespread technology that is used to treat sewage sludge from wastewater. Mixing has been proven to be a key element for a well-performed digester but it is a power-intensive operation whose quantitative contributions to the system's energy-efficient balance in different designs is not well understood. In order to cut costs, operators try to keep mixing to minimum levels where biogas production is not adversely affected. However, sewage sludge inherently contains inert dense particles, such as grit, that cannot be biodegraded and tend to accumulate at the bottom of the digester. For the first time, the impact of inert particle suspensions on biogas production was evaluated at a range of mixing speeds and particle loadings in mechanically-mixed, laboratory-scale digesters. Five digesters were operated for a total period of five months at different speeds and particle loadings whilst digestion stability, biogas production and treatment quality were monitored. Digesters were fed with real sewage sludge samples six days a week. Computational fluid dynamics models were used to assess the liquid-solid flow characteristics. It has been shown that inert particles in suspension at highly-intensive mixing detrimentally affects anaerobic digestion performance and biogas yields. Low-speed mixing does not suspend inert particles but the digesters are not affected by their presence. Short-term, highly-intensive intermittent mixing, along with continuous low intensive mixing, resulted in particle suspension, stable digestion and biogas production; this being the best energy-efficient mixing regime. Computational fluid dynamics has successfully simulated sedimentation behaviour as well as particle solid distribution and cloud height within the liquid column. The liquid flow patterns change with increased particle loadings.

The field of ecological epigenetics aims to understand the implications of epigenetic modifications in adaptation, inheritance and ultimately, evolution. Many questions remain open within ecological epigenetics, in particular, how epigenetic variation is influenced by genetic background, the extent of environmentally-induced epigenetic variants, as well as its degree of heritability. This thesis used the unique diversity of mating systems present in the killifish genus Kryptolebias to investigate how genetic and environmental variation shape epigenetic variation in animals. Genetic and epigenetic structure was investigated in natural populations of K. hermaphroditus in northeast Brazil, with the species being confirmed as the second example of mixed-mating system in vertebrates. Cytosine methylation was largely influenced by genetic background. However, within-populations, when individuals were more genetically similar, DNA methylation was mostly affected by parasites. Kryptolebias ocellatus, here confirmed as an outcrossing-only androdioecious species, showed deep genetic structure in southeast Brazil. Hybridisation between K. ocellatus and the predominantly selfing K. hermaphroditus was uncovered, representing the first example of hybridisation between species with different mating systems in vertebrates. Hybrids had intermediate patterns of cytosine methylation relatively to the parental species, with important biological processes being potentially misregulated. Environmental enrichment was shown to affect brain cytosine methylation patterns in two inbred strains of K. marmoratus, however genetic background had a stronger effect than environmental variation. Commonly-affected epialleles between genotypes predominantly showed a genotype-by-environment reaction norm, suggesting that exclusively environmentally-induced epialleles may be rare. Intergenerationally, parental activity affected offspring activity, and a limited number of putative intergenerational epialleles were identified. This is the first example of behavioural parental effects induced by environmental enrichment in fish. These findings show that genetic background has a prominent effect and must be take into account when evaluating the evolutionary potential of cytosine methylation variation. In addition, inheritance of environmentally-induced cytosine methylation epialleles may be limited, with other epigenetic mechanisms, such as microRNAs, being more likely to escape epigenetic reprogramming and transmit epigenetically-induced parental effects.

The main goal of this thesis is to analyse how the relationship between the earthly world and the supernatural world (heaven and hell) are represented in Oxford Bodleian Library Junius 11 in text and image, and on this basis to trace how the Anglo-Saxons understood and located the place of the human in the Universe. Junius 11 is one of the major Anglo-Saxon poetic manuscripts, and has remained relatively complete until today, containing the four biblical poems: Genesis, Exodus, Daniel, Christ and Satan. It is also the only illuminated manuscript of Anglo-Saxon poetry to survive, with drawings completed through part of the poem Genesis. In chapter 01 I will explain in detail the aims of this thesis, the manuscript features and story (possible year of production, and provenance), and the general methodology about the approach towards text and pictures in manuscripts and medieval art in general. In chapter 02 I will analyse the function of the architectural elements especially in the images of heaven and their function as representation of power, both political and religious, not simply as ornamentation in the manuscript. In chapter 3 I will focus on the images and text of hell in Junius11 and how it is pictured as a chthonic psychological space, the place of the uncanny, through three main features: anti-hall, tomb and hellmouth, and womb (the feminine body). In chapter 4 the main focus will be the space of the earth, earthly paradise and the idea of earth as an island, I also added a section about the funerary practices in late Anglo-Saxon England. In conclusion, this thesis will demonstrate how the different spheres, heaven, hell and earth were depicted in Junius 11, how their relationship works and possible connections with the daily live, political power, attitudes about gender, funerary practices and conceptions about their place in the earthly world and in the supernatural world, that is life after death.

This thesis develops a teleological theory of mental representation to naturalise intentionality. Teleosemantics explains mental representation in terms of biological functions. The thesis addresses a number of foundational problems that threats the viability of teleosemantics. The first chapter, “The metaphysics of mental representation”, develops a basic conception of mental representation that is designed to satisfy certain intuitive requirements (misrepresentation and original intentionality) and methodological requirements (explanatory power and ontological parsimony). The second chapter, “Naturalising intentionality”, defends the thesis that mental representation is naturalistically reducible and in particular that it should be explained teleosemantically. After that, it addresses some of Tyler Burge’s objections to reductionist naturalism in general and teleosemantics in particular. The third chapter, “The minimal conditions for intentionality: the problem of demarcation”, considers the problem of demarcating the limits of intentionality and the objection that teleosemantics and other naturalist theories are too liberal. It adopts the method of reflective equilibrium to develop minimal conditions for intentionality based on mutual adjustments between intuitive and explanatory constraints. Finally, it rejects alternative proposals for demarcating intentionality in terms of causal independence or constancy mechanisms. The fourth chapter, “The minimal conditions for intentionality: the dual proposal”, develops a specific solution to the problem of demarcation – the dual proposal for the minimal conditions for intentionality. The fifth chapter, “The content problem: in defence of producer-based teleosemantics”, defends a producer-based version of teleosemantics and proposes solutions for functional indeterminacy problems facing teleosemantics.

Contemporary software systems often have millions of lines of code that interact over complex infrastructures. The development of such systems is very challenging due to the increasing complexity of services and the high level of dynamism of current operating environments. In order to support the development and management of such systems, autonomic computing concepts have gained significant importance. The majority of autonomic computing approaches show significant levels of expert dependency in designing adaptive solutions. These approaches usually rely on human-made models and policies to support and guide software adaptation at runtime. These approaches mainly suffer from: i) a significant upfront effort demanded to create such solutions, which adds to the complexity of creating autonomous systems, and ii) unreliability given the high levels of uncertainty in current operating environments, leading the system to degraded performance and error states when subjected to unpredicted operating conditions and unexpected software interactions. Motivated by the problems and limitations of state-of-the-art autonomic computing solutions, this thesis introduces the concept of Emergent Software Systems. These systems are autonomously composed at runtime from discovered components, and are autonomously optimised based on the operating conditions, being able to build their own understanding of their environment and constituent parts. This thesis defines Emergent Software Systems, presenting the challenges of implementing such approach, and presents a fully functioning emergent systems framework that demonstrates this concept in real-world, fully functioning datacentre-based software.

The ability to synthesize recordings from surface data as if they had come from subsurface sources has allowed geophysicists to estimate subsurface properties. Either in the form of classical seismic migration which creates structural maps of the subsurface, to the more recent seismic interferometry which turns seismic sources into receivers and vice-versa, this ability has provided a rich trove of methods with which to probe the Earth's interior. While powerful, both of these techniques suffer from well-known issues. Standard migration requires data without multiply-scattered waves (multiples). Seismic interferometry, on the other hand, can be applied to full recorded data (containing multiples and other wave types), but requires sources (receivers) to be physically placed at the location from (to) one wishes to estimate responses. The Marchenko method, developed recently for the seismic setting, circumvents both of these restrictions: it creates responses from virtual subsurface sources as if measured at the surface. It requires only single-sided surface data, and a smooth estimate of the subsurface velocities. Initially developed for acoustic media, this thesis contributes the first elastic formulation of the Marchenko method, providing a more suitable setting for applications for the solid Earth. In another development, this thesis shows how the obtained virtual recordings may be used for migration. With these two contributions, this thesis shows that for elastic surface seismic data, the main drawbacks of migration and interferometry can be overcome using the Marchenko method: multiples do not harm migrated images, and sources (receivers) need not be physically placed in the medium for their responses to be accessible. In addition to the above methods, generating images devoid of multiple-related artifacts can be achieved in several other different ways. Two approaches to this are the use of a post-imaging filter, and attenuation of internal multiples in the data itself. This thesis contributes one new method using each of these approaches. First, a form of Marchenko imaging is known to create spurious reflectors, as also occurs in standard reverse-time migration (RTM). However, these artifacts usually appear at different locations in RTM and this form of Marchenko imaging. Using this insight, this thesis presents a way to combine pairs of seismic images in such a way that their differences (e.g. artifacts) are attenuated, while similarities (e.g. true reflectors) are preserved. Applying this to RTM and Marchenko-derived images markedly improves image quality. Second, this thesis presents a method to estimate multiples in the data. Multiples can either be migrated on their own to aid in interpretation, or be adaptatively removed from the data to improve image quality. However, because of the nature of adaptive subtraction, this second method may harm primary energy. To avoid this problem, this thesis develops a final method to directly image using only primary energy in the recorded data using only a small number of virtual points. This method bypasses the need for multiple removal and the estimation of subsurface responses at every depth location. In addition, primaries from particular reflectors may be particularly selected such that they can be imaged individually. Overall this thesis provides several new ways to use surface seismic data in such a way that multiples do not hamper the end product of seismic data processing: the seismic image. It demonstrates this use on synthetic and real data, proving their effectiveness.

In Europe and beyond, pilgrimage centres attract millions of visitors each year. This popularity has provoked a burgeoning academic interest in pilgrimage, and this thesis builds on this expanding literature. It emerges out of a dialogue between old and new forms of movement – a conversation that demands further research on the relationship between religious traditions and late–modern consumer culture, a dialogue made explicit through the study of pilgrimage. Although this thesis pays attention to one case study in particular, namely the Camino de Santiago de Compostela in northern Spain, it draws on multi–disciplinary research in order to set a broader context. It reveals four motivational themes, derived from interviews with pilgrims on the road to Compostela. These I explore in depth through qualitative analysis, while at the same time taking note of parallel quantitative work concerned with the Camino de Santiago as well as other pilgrimage sites in Europe. Ranging from the search for spirituality to recreation, motivations are found to be the result of a conflation of meanings; they are ambiguous narratives, which very often include spiritual as well as secular aspirations. My findings suggest a de–differentiation of poles of meaning such as sacred and profane, movement and place, religion and secularity, community and individual. In short, this is a methodologically diverse study which argues that, contrary to perception, traditional forms of religious rituals are not necessarily incompatible with late–modern consumer culture. Through consumer culture religious traditions are being revitalized. The renewed popularity of pilgrimage today demonstrates how some religious landscapes and spaces have remained important through political and religious movements, while others have been regenerated by literature, new media, specialist tourist markets, advertising and private enterprise. Finally, this study reveals a noticeable democratization of traditional rites, and the landscapes in which they take place. A very wide variety of groups and individuals visit them.

The development of multi-agent software systems is considered a complex task due to (a) the large number and heterogeneity of documents generated during the development of these systems, (b) the lack of support for the whole development life-cycle by existing agent-oriented methodologies requiring the use of different methodologies, and (c) the possible incompleteness of the documents and models generated during the development of the systems. In order to alleviate the above problems, in this thesis, a traceability framework is described to support the development of multi-agent systems. The framework supports automatic generation of traceability relations and identification of missing elements (i.e., completeness checking) in the models created during the development life-cycle of multi-agent systems using the Belief-Desire-Intention (BDI) architecture. Traceability has been recognized as an important activity in the software development process. Traceability relations can guarantee and improve software quality and can help with several tasks such as the evolution of software systems, reuse of parts of the system, validation that a system meets its requirements, understanding of the rationale for certain design decisions, identification of common aspects of the system, and analysis of implications of changes in the system. The traceability framework presented in this thesis concentrates on multi-agent software systems developed using i* framework, Prometheus methodology, and JACK language. Here, a traceability reference model is presented for software artefacts generated when using i* framework, Prometheus methodology, and JACK language. Different types of relations between the artefacts are identified. The framework is based on a rule-based approach to support automatic identification of traceability relations and missing elements between the generated artefacts. Software models represented in XML were used to support the heterogeneity of models and tools used during the software development life-cycle. In the framework, the rules are specified in an extension of XQuery to support (i) representation of the consequence part of the rules, i.e. the actions to be taken when the conditions are satisfied, and (ii) extra functions to cover some of the traceability relations being proposed and completeness checking of the models. A prototype tool has been developed to illustrate and evaluate the work. The work has been evaluated in terms of recall and precision measurements in three different case studies. One small case study of an Automatic Teller Machine application, one medium case study of an Air Traffic Control Environment application, and one large case study of an Electronic Bookstore application.

Management in ubiquitous systems cannot rely on human intervention or centralised decision-making functions because systems are complex and devices are inherently mobile and cannot refer to centralised management applications for reconfiguration and adaptation directives. Management must be devolved, based on local decision-making and feedback control-loops embedded in autonomous components. Previous work has introduced a Self-Managed Cell (SMC) as an infrastructure for building ubiquitous applications. An SMC consists of a set of hardware and software components that implement a policy-driven feedback control-loop. This allows SMCs to adapt continually to changes in their environment or in their usage requirements. Typical applications include body-area networks for healthcare monitoring, and communities of unmanned autonomous vehicles (UAVs) for surveillance and reconnaissance operations. Ubiquitous applications are typically formed from multiple interacting autonomous components, which establish peer-to-peer collaborations, federate and compose into larger structures. Components must interact to distribute management tasks and to enforce communication strategies. This thesis presents an integrated framework which supports the design and the rapid establishment of policy-based SMC interactions by systematically composing simpler abstractions as building elements of a more complex collaboration. Policy-based interactions are realised – subject to an extensible set of security functions – through the exchanges of interfaces, policies and events, and our framework was designed to support the specification, instantiation and reuse of patterns of interaction that prescribe the manner in which these exchanges are achieved. We have defined a library of patterns that provide reusable abstractions for the structure, task-allocation and communication aspects of an interaction, which can be individually combined for building larger policy-based systems in a methodical manner. We have specified a formal model to ensure the rigorous verification of SMC interactions before policies are deployed in physical devices. A prototype has been implemented that demonstrates the practical feasibility of our framework in constrained resources.

Estuaries are the interface between freshwater systems and the sea, with clearly recognizable changes in the distribution of organisms along various environmental gradients from riverine to fully marine conditions. This thesis studied ecological processes affecting the distribution of marine species along estuarine gradients using both field and laboratory experiments with barnacles as a tractable model system. Elminius modestus Darwin, Semibalanus balanoides Linneaus, Chthamalus montagui Southward are the most common barnacle species found in the intertidal of British estuaries. Surveys performed in the Plym and the Yealm Estuaries revealed that E. modestus occurred furthest up estuaries and was dominant along most of their length, with the exception of sites closest to the sea; C. montagui had the most restricted degree of penetration up-estuary; and S. balanoides occurred at low abundances, with limits of penetration located between those of C. montagui and E. modestus. Transplants of adult specimens to sites along the marine-to-freshwater gradient revealed that E. modestus was better adapted to environmental conditions found in inner areas of the estuaries than C. montagui and S. balanoides. Survival of the latter two species was negatively correlated with deposition of silt and decreasing salinity. Laboratory experiments showed that, in contrast to the other two species, E. modestus was highly tolerant to burial by silt. A comparison of observed distributions along the gradients with survivability showed that C. montagui was able to survive in areas where adults were absent, indicating that early life cycle stages were a potential limiting factor to the distribution of this species. Examination of patterns of cyprid settlement and recruitment to the benthic phase reinforced the suggestion that pre-settlement processes contribute to restrictions in the distribution of both C. montagui and S. balanoides. The abundance of these species, post-settlement, was also affected by physico-chemical conditions in the upper estuary. Pre-settlement processes did not limit the distribution of E. modestus and post-settlement processes appeared to be more important in limiting its abundance at sites closest to the sea.

Bridge Management Systems have been an emergent area of research in this decade. This has been fostered by the recognition of the need for computer support in the decision making process involved in defining maintenance and improvement strategies to networks of bridges. While existing systems have already prove their worthiness, there are still far from satisfying entirely the complex and evolving user needs. Changing society perceptions are introducing new requirements and demanding the consideration of issues like environmental quality and congestion minimisation. At the same time, IT developments are opening various new alternatives to the problem of creating flexible, user-friendly and easily maintainable systems. Given this panorama, this study investigates the possibility of developing more advanced Bridge Management Systems that could lead to a more open, integrated and socially aware approach to Bridge Management. It proposes the adoption of a new appraisal model based on a wider consideration of maintenance and deterioration consequences and an innovative view of bridge utility as a measure of benefits. An innovative system architecture is used to support the model based on three main elements: object orientation, geo-referencing and soft reasoning. The results obtained indicate that the use of this new approach can significantly alter the allocation of the budget. The conclusion of the work is that it is possible to develop more advanced systems and that the adoption of the framework proposed can have a significant impact on Bridge Management decision-making. Further researches will be necessary to refine the model and investigate how to develop other components of an ABMS. The flexibility of the system architecture proposed is an important advantage in this sense because it allows a progressive and steady advance, with the results of new researches being gradually and seamlessly incorporated.

This thesis investigates the impact of trade unionism and consumer behaviour on economic performance in Britain. The economic performance measures used in this research are profitability and the level of R&D expenditures. Firm and plant level data are used in the investigation and the main findings are as follows: Unionization, on average, impacts negatively on the profitability of UK firms, even after controlling for firm specific effects. However, the union effect on profitability has decreased dramatically over the 1980s and this may bear a relationship with the anti-union legislation that took place during that period in Britain. It also seems that the union effect depends a great deal on the prevailing bargaining structure, so that the industrial relations regime has an important say in the union capacity to extract rents. In terms of the relationship between unionization and R&D expenditures, whenever human capital and technological opportunities are controlled for, the negative association present in the raw data completely disappears. This result is obtained using two completely independent data sets, one at the firm and the other at the plant level. Furthermore, some evidence was found, both in the firm and in the plant level data, of a non-linear (concave) relationship between unions and R&D investment. The combination of supply and demand information, to analyze the interaction between consumers and firms in several markets, produced very interesting results. Demand elasticities, estimated using household level data, have a sizable and significant impact on firms' markups, computed from company accounts data. Time-varying household characteristics provide a unique instrument set that can be used to identify the supply equation. Interactions of the demand elasticities with market structure variables tend to show that the effects of industry concentration and import penetration on profitability are stronger in industries where demand is elastic, which can be seen as evidence against the "collusion" explanation of the link between market structure and profitability.

The behaviour mediated by chemical communication of laboratory-reared Euschistus heros Fabricius was studied in cultures initiated with egg masses supplied from EMBRAPA in the Southern region in Brazil. The courtship behaviour of E. heros is described and this behaviour can be divided into two phases: long-range mate location and short-range courtship. The first comprises a sequence of movements, such as intense antennation and movement of wings, which leads the female to the vicinity of males. The second includes the interaction of both sexes once they are in close proximity. The first mating is observed in male insects between 12 to 15 days old and in female e. heros from between 10 to 14 days old. Both the quantitative and qualitative analysis of the data strongly suggest that male insects produce a sex pheromone that elicits attraction and mating behaviour in this species. For E. heros, the chances of attraction and mating are greater for males and females during the photophase and are greater if the females are attracted towards males. When the odour of live males was replaced by chemical extracts obtained by aeration collection from female insects, females were much more attracted to the test chamber of a dual-choice olfactomter. This finding also suggested that males release the pheromone blend that elicits sexual behaviour in females E. heros. Pentatomids are known to produce and release a defensive secretion when distributed. It is believed that the defensive secretions in adult insects are produced in metathoracic glands, which occupy a ventral position in the hind part of the metathorax, and are stored in the reservoir. Secretions are ejected when the insects are disturbed by, for example, a predator, eliciting an alarm behaviour. Both male and female E. heros release such a defensive secretion, however, the female defensive secretion is more concentrated than that of the male.

This thesis introduces techniques to build novel ES systems. The main contributions are the microwave phase neuron and the fuzzy classifiers. Unlike most of the work available in literature, which present future ES by the sight of traditional methods, this thesis discusses two novel proposals. The first chapters formalise some theoretical points, while the last chapters describe and analyse the proposed novel designs. Chapter 1 introduces Electronic Warfare (EW). It also analyses the electromagnetic environment faced by a naval platform and the traditional ES systems. Chapter 2 makes use of fuzzy theory to provide a formal theoretical study of signal classification in EW. Chapter 3 analyses the heuristics applying fuzzy logics, fuzzy numbers and fuzzy aggregation connectives. Chapter 4 presents the microwave phase neurons. It describes the basic mathematical formulation and the evolution of this concept from its early stages. It also presents the results obtained from simulation of several phase-neuron topologies. The phase neuron is a completely new artificial neural network paradigm. Chapter 5 models fuzzy inference engines. It indicates how these systems work in several different situations and analyse the results of several simulations. It investigates data-fusion techniques and the demands of automatic target recognitors (ATR). This chapter introduces the fuzzy classifiers and the fuzzy identification filters (FIF). Each FIF combines the outputs of the several classifiers to calculate the degree of belief of each possible outcome. This new architecture is another main contribution of this work. Chapter 6 presents the work being presently conducted with microwave classifiers. The results from the simulation of some possible system architectures are commented. Chapter 7 presents the final conclusions and provides suggestions for further research.

Three Brazilian yeast strains, Saccharomyces cerevisiae 42 - F, Saccharomyces cereviaiae PLA 851 and Saccharomyces boulardli IZ 1904, all currently employed in the sugar fermentation industry, were evaluated with respect to their thermal tolerance and alcohol production kinetics. Best performance was found in Saccharomyces cerevisiae PLA 851 at temperatures up to 40 degrees (a common fermentation temperature in the Brazilian industry). This strain was further evaluated in chemostatic growth under sucrose limitation with biomass feedback on a 1 Litre scale in a specially constructed apparatus. At 30 degrees and 35 degrees under a dilution (growth) rate of 0.1 /h ethanol productivity increased by a factor of 2 with feedback and at 40 degrees by a factor of 3. The feedback factor (Beta) was 0.9. PLA 851 cells, heat - shocked at 45 degrees, resulted in a greater biomass productivity subsequently at 40 degrees coupled with a change in cell morphology. Highest ethanol productivity was found with 10% initial sucrose concentration at a dilution rate of 0.25 /h with feedback. Saccharomyces cerevisiae PLA 851 appears to be well adapted to the harsh physiological conditions in alcohol fermentations as currently practiced in Brazil.

This thesis investigates an object-oriented programming environment for building parallel applications based on genetic algorithms (GAs). It describes the design of the Genetic Algorithms Manipulation Environment (GAME), which focuses on three major software development requirements: flexibility, expandability and portability. Flexibility is provided by GAME through a set of libraries containing pre-defined and parameterised components such as genetic operators and algorithms. Expandability is offered by GAME'S object-oriented design. It allows applications, algorithms and genetic operators to be easily modified and adapted to satisfy diverse problem's requirements. Lastly, portability is achieved through the use of the standard C++ language, and by isolating machine and operating system dependencies into low-level modules, which are hidden from the application developer by GAME'S application programming interfaces. The development of GAME is central to the Programming Environment for Applications of PArallel GENetic Algorithms project (PAPAGENA). This is the principal European Community (ESPRIT III) funded parallel genetic algorithms project. It has two main goals: to provide a general-purpose tool kit, supporting the development and analysis of large-scale parallel genetic algorithms (PGAs) applications, and to demonstrate the potential of applying evolutionary computing in diverse problem domains. The research reported in this thesis is divided in two parts: i) the analysis of GA models and the study of existing GA programming environments from an application developer perspective; ii) the description of a general-purpose programming environment designed to help with the development of GA and PGA-based computer programs. The studies carried out in the first part provide the necessary understanding of GAs' structure and operation to outline the requirements for the development of complex computer programs. The second part presents GAME as the result of combining development requirements, relevant features of existing environments and innovative ideas, into a powerful programming environment. The system is described in terms of its abstract data structures and sub-systems that allow the representation of problems independently of any particular GA model. GAME's programming model is also presented as general-purpose object-oriented framework for programming coarse-grained parallel applications. GAME has a modular architecture comprising five modules: the Virtual Machine, the Parallel Execution Module, the Genetic Libraries, the Monitoring Control Module, and the Graphic User Interface. GAME's genetic-oriented abstract data structures, and the Virtual Machine, isolates genetic operators and algorithms from low-level operations such as memory management, exception handling, etc. The Parallel Execution Module supports GAME's object- oriented parallel programming model. It defines an application programming interface and a runtime library that allow the same parallel application, created within the environment, to run on different hardware and operating system platforms. The Genetic Libraries outline a hierarchy of components implemented as parameterised versions of standard and custom genetic operators, algorithms and applications. The Monitoring Control Module supports dynamic control and monitoring of simulations, whereas the Graphic User Interface defines a basic framework and graphic 'widgets' for displaying and entering data. This thesis describes the design philosophy and rationale behind these modules, covering in more detail the Virtual Machine, the Parallel Execution Module and the Genetic Libraries. The assessment discusses the system's ability to satisfy the main requirements of GA and PGA software development, as well as the features that distinguish GAME from other programming environments.

The design, fabrication and characterisation of monolithic passive colliding pulse mode-locked (CPM) quantum well lasers are described. Firstly, a standard configuration of CPM laser is realised and mode-locking is obtained at repetition rates in the range of 73 to 129 GHz. These are the first published results on monolithic CPM quantum well laser at short wavelength, i.e. GaAs/AlGaAs based material. This device presented a previously unseen output laser polarisation dependence with the applied reverse bias to the absorber section of this laser. The generation of TE and TM polarised light from the CPM laser is analysed and discussed. A novel configuration of CPM laser, the multiple colliding-pulse mode-locked (MCPM) laser is realised. This multi-section device can have 1, 2, or 3 monolithically integrated saturable absorber sections in the cavity, inducing the laser to operate at the first up to the fourth harmonic of the repetition rate. This is the first observation of geometry dependent switcheable change of harmonics in mode-locked lasers. The different regimes of operation of the MCPM laser are investigated, comprising single mode, multimode, Q-switched and first to fourth harmonic mode-locking, generating pulses of around 1 to 3 ps width at up to 375 GHz repetition rate. Studies of the range of mode-locking at 240 GHz show that mode-locking occurs at two distinct regions of current and reverse bias. This previously unseen feature may represent an indication of the contribution of excitonic nonlinearities to the ultra-fast operation of the device. A monolithic CPM ring laser with two saturable absorbers in the cavity is described. Frequency domain measurements indicate mode-locking operation at 28 GHz repetition rate. The use of two saturable absorbers in colliding pulse configuration in the ring cavity showed improvements on the device operation. The design and fabrication of a CPM laser based device which is intended to perform clock recovery at high repetition rates, above 100 GHz, is described. This device consists of a standard CPM laser which has an extra waveguide in side-injection configuration. This extra waveguide amplifies and guides the optical signal from which the clock is to be recovered to the absorber section of the laser. To achieve clock recovery this signal should contribute to the saturation of the absorber section of the CPM laser, synchronising its saturation with the injected data signal. Preliminary characterisation and tests showed that the CPM laser part of the device works as a standard CPM laser, as expected.

This thesis is a contribution to recent debates on the labour theory of value (LTV). It builds upon two distinctive features of the LTV; first, the categories used in the inquiry are historically determined modes of existence of capitalist social relations; second, it rejects equilibrium as the organizing principle of the investigation. Six issues are analysed in the light of these elements and the previous literature. First, the relationship between dialectical logic and the LTV is addressed through an evaluation of the 'new dialectics'. This approach to Marx's method understands the LTV as a systematic dialectical theory, whose aim is the reconstruction in thought of the main characteristics of capitalism. Second, the relationship between labour and value is assessed through the real processes that determine value and price, the normalization, synchronization and homogenization (NSH) of labour. Three well-known views of the LTV are assessed in this light; the traditional, the Sraffian, and the 'abstract labour' view. Third, the monetary reform devised by the 'Ricardian socialist' economists in the 19th Century, which was centred around the institution of a 'labour-money'. This plan, and Marx's critique of it, are investigated from the viewpoint of the NSH of labour. Fourth, the distinction between the technical, organic and value compositions of capital (TCC, OCC and VCC). The evolution of Marx's use of these terms is reconstructed, and their place in his analysis is brought to light. Fifth, the transformation of values into prices of production is reinterpreted in the light of the distinction between OCC and VCC. This view of the transformation is contrasted with the concerns of the critics of Marx's approach. Sixth, the contribution of the 'new approach' to the transformation problem to the LTV is evaluated in detail.

This thesis is concerned with applications in probability and statistics of approximation theorems for weakly dependent random vectors. The basic approach is to approximate partial sums of weakly dependent random vectors by corresponding partial sums of independent ones. In chapter 2 we apply such a general idea so as to obtain an almost sure invariance principle for partial sums of Rd-valued absolutely regular processes. In chapter 3 we apply the results of chapter 2 to obtain functional limit theorems for non-stationary fractionally differenced processes. Chapter 4 deals with applications of approximation theorems to nonparamatric estimation of density and regression functions under weakly dependent samples. We consider L1-consistency of kernel and histogram density estimates. Universal consistency of the partition estimates of the regression function is also studied. Finally in chapter 5 we consider necessary conditions for L1-consistency of kernel density estimates under weakly dependent samples as an application of a Poisson approximation theorem for sums of uniform mixing Bernoulli random variables.

We study various aspects of the dynamics of skew-products (Rand Z-extensions) over a subshift of finite type (ssft). In Chapter I we give the basic definitions and terminology. Conditions are given in Chapter II to ensure ergodicity of the skew-product defined by a function of summable variation with respect to an invariant measure u x ⋋ where u is an ergodic shift-invariant Borel probability measure which is quasi-invariant under finite coordinate changes in the shift space (or under finite block exchanges), and ⋋ denotes Lebesgue measure on R or Z (depending on whether the function is real or integer valued). In Chapter III we define a topological entropy concept for the skew-product (defined by a Holder continuous function f), which is given by the growth rate of periodic orbits of bounded f-weights, and we show that this is the minimum value of the pressure function of f. The asymptotics in the central limit theorem is studied in Chapter IV, for the class of Holder continuous functions defined on a subshift of finite type endowed with a stationary equilibrium state of another HOlder continuous function.