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This thesis investigates how teachers and other local actors in France and England have enacted national-level responses to the context of terrorism. These include the Great Mobilisation of the School for the Values of the Republic and the duty to promote fundamental British values, which aim to promote core national values among young people to promote social cohesion and build resilience to radicalisation. France's Policy for Preventing Violent Radicalisation in Schools and England's Prevent duty outline procedures for identifying and reporting suspected cases of radicalisation. The common emphasis on shared values reflects the transnational trend towards civic integration, wherein Western democracies have placed a greater emphasis on liberal-democratic values as a tool for the integration of migrants and minorities. Despite these convergent trends, there is a tendency in the comparative literature to contrast the British 'multicultural' approach to immigrant integration with the French 'republican' or 'assimilationist' approach. Drawing on eight school-based case studies and further interview and observational data, this thesis provides an empirically grounded account of how these particularistic policy traditions and convergent trends are reflected in the enactment of the policies at the local level, as well as in teachers' ideas. It finds that in both countries, policymakers and practitioners have drawn on institutionalised ideas and practices in their responses to recent terrorist attacks or their enactment of national policies, leading to some path dependencies. However, policymakers have also looked beyond prevailing paradigms in the face of emerging challenges. Some of the convergence observed at the national level is evident at the school level. The comparative research design also provides new insights into the governance of the two education systems and reveals that local actors in France have greater decision-making capacity than earlier comparative work would suggest.

Both mechanical and chemical finishing process are regularly used to reduce frictional losses and improve the wear resistance of components within mechanical systems like internal combustion engine cylinders and fluid pumps. Coatings often require highly specialised equipment and are usually expensive in comparison to mechanical processes. In many applications, both mechanical finishing and chemical coatings are applied to component surfaces in order to achieve a surface with all the desired properties. This thesis applies tribofilm forming research when using particular nano-additives to mechanical finishing processes in order to mechanochemically generate a tribologically superior surface through a simple, single stage operation. Cast iron plates were honed against grit paper with dry Cu₂S microparticles causing a reduction reaction in the particles for sulphur to then react with the iron in the plates. Energy Dispersive Spectroscopy (EDS) revealed a huge increase in the quantity of copper in the cast iron caused by the mechanochemical honing. X-ray Photoelectron Spectroscopy (XPS) did suggest a small quantity of iron sulphides had formed. While the honing process did successfully reduce the copper sulphide, a lot of the sulphur was lost in the process while the copper sintered into the surface. Lubricated friction tests at a variety loads showed a small reduction in friction with the copper honed samples. In order to better understand mechanisms for tribofilm formation and discover any synergistic behaviours between nano-MoS₂ and ceramic nanospheres, SiO₂ was tested with MoS₂ as lubricant additives in a variety of High Frequency Reciprocating Rig (HFRR) tests. At high load and 50 °C the two nanoparticles on their own could not improve friction or wear but when used together, the SiO₂ improved the conditions for MoS₂ to chemically react with the steel contacts forming a protective tribofilm. This was characterised through a combination of EDS and Hard X-Ray Photoelectron Spectroscopy (HAXPES). Attempts to recreate these results in the TE 77 High Frequency Friction Machine (TE 77) low load adapter were unsuccessful. Keeping lubricant additives successfully dispersed is a well documented issue. To get round this, Cu₂S and Al₂O₃ microparticles were mixed with a base grease whose viscosity was great enough that once dispersed the particles could not settle. The formulated greases were put under very high load (920N) in line contact in the TE 77 to generate a tribofilm style layer that was then tested with point contact wear in a base lubricant. The formulated greases were tested against a commercial grease containing MoS₂. At low loads, only the MoS₂ treated surface produced lower friction than the untreated plate. In 50 °C tests at a higher load, all the treated surfaces slightly reduced friction compared to the untreated plate and the hybrid Cu₂S, Al₂O₃ surface had the lowest friction. MoS₂ produced the shallowest scar with a tribofilm similar to that generated with the hybrid lubricant in the previous chapter. This thesis introduces a proof of concept for two mechanochemical finishing processes as well as developing understanding for the synergistic behaviour of Transition Metal Dichalcogenides (TMDC) and ceramics as nano-additives in lubricants. The potential scope for this research is huge as the finishing processes could be beneficial to any mechanical system where there are sliding metal contacts. A large amount of work is still needed to bring this work from its concept stage to full realisation in a commercial setting.

This thesis investigates the occurrence, characteristics and effects of Very Fast Transients (VFTs) associated with disconnector switching operations in Gas Insulated Substations. VFTs are analysed and efforts are made to elucidate their behaviour through advanced simulation techniques. The initial motivation for this work was the occurrence of a surface flashover at a spacer, leading to a prolonged outage of the circuit in question and a significant repair effort. While post failure investigations were carried out by the manufacturer and yielded no significant observations, through modelling and measurements efforts while working towards this thesis, a phenomenon that could have led or contributed to the failure. VFTs at a live, operational 400kV Substation (un-named for confidentiality but termed throughout as Substation 'A') are quantified through both modelling and measurements. Significant progress in the modelling of VFTs and TEVs is demonstrated. Numerical Electromagnetic Analysis is shown to be most effective method in studying the behaviour of the GIS and earthing systems. Multiple NEA techniques are utilised, all solving a full-Maxwell's equations through a Wave equation. The behaviour of the system (both internally and externally) is captured with great accuracy and lucidity, without the need to use analytic approximations or assumed parameters, which has traditionally been the case. Detailed models were built using equipment drawings from Substation 'A' for the GIB, spacer-flange assembly, double-elbow assembly, disconnector, gas to air bushing. Frequency and time domain behaviour is analysed and a potential contributor to the failure at Substation 'A' is identified. Furthermore, elements of the earthing system were evaluated for effectiveness in mitigating TEVs. The methods highlight some of flaws and inaccuracies that are present with existing 'standard practice' modelling efforts. The need for circuit-based modelling for VFT studies is apparent, as NEA techniques at very high frequencies are limited in their interaction with the wider system. Efforts are therefore made to enhance circuit-based models; utilising NEA methods and Vector Fitting to produce accurate, large bandwidth equivalent circuits, which demonstrate the computed frequency responses of the various GIS equipment types studied. Vector Fit models at lower orders of approximation are prone to unstable time domain responses, leading to numerical oscillations or even a complete divergence from a solution. A method was developed to identify model orders that demonstrate stability in the time domain, allowing the lowest model order of approximation to be selected, thereby reducing the additional computational requirements of very high orders of approximation, while retaining accuracy and stability in the time and frequency domains. The conversion process is augmented with a new method for identifying model orders that will be stable in the time domain. Several measurement techniques and sensors were developed to capture the entire cycle of transients associated with disconnector operations. Device prototypes were designed and optimised through NEA/circuit-based modelling, prior to undergoing laboratory-based measurements. Laboratory based testing was conducted using a custom built, half scale GIB, with impedance matching cones at each end to allow measurement and signal generating equipment to be connected with minimal interference. While, essential, laboratory-based measurements will never replicate the transient and high EMI environmental conditions seen at a live GIS, therefore, the bulk of the measurement efforts were focused on live measurements at Substation 'A'. Throughout the course of this project several opportunities to undertake measurements were presented and a significant amount of data was recorded. Each measurement also identified areas for improvement of the measurement systems.

Collaborative learning is commonly advocated in places of advanced musical training, yet classical and jazz students tend to remain in separate 'tribes' from a curricular perspective. When they do collaborate across styles in a creative exercise, the learning is not always reciprocal, with the jazz musician typically more adept at improvisatory tasks. This research addresses how 'collaborative musical creativity' may be understood before proposing a 'reinvention method' for paired improvisation across styles, with the aim of encouraging a more profound and equal sharing of knowledge and skills. 'Collaborative musical creativity' is a very fluid concept that resists empirical assessment, particularly when observing how it is expressed by advanced musicians in an open-ended task. The methodology and case study design bring definition through framing the concept from four perspectives: creative cognition, socio-cultural learning theory, musicological analysis and theories around collaborative creativity. Comparative case studies were conducted over eighteen months with six advanced instrumentalists (average age 17, post grade 8) with either classical or jazz as their primary study. Drawing on models for creative cognition proposed by Finke (1996, 1992) and Webster (2002, 1990), as well as tactics typically used by an orchestral workshop leader, a series of cross-stylistic 'reinvention exercises' were devised that incorporate a cycle of convergent and divergent creative thinking, carried out individually and in pairs. In the main phase, paired participants are asked to deconstruct three pieces (two specially composed by the author, one by Stravinsky) that each carry a different style bias, and then 'reinvent' them together through improvising in their own musical language. Data was collected through semi-structured interviews, self-assessment questionnaires and both video and audio recordings, thematically coded to highlight cognitive, collaborative and pedagogical processes. Post-Vygotskian socio-cultural theories around paired learning (mainly relating to Participation theory, Rogoff 2008) are examined in practice. The research validates the reinvention method as a means of facilitating cross-stylistic improvisation and reciprocal learning in pairs, and advocates for its wider application in a variety of music educational contexts.

This thesis establishes a generalised setting with which to unify the study of finite local complexity (FLC) patterns. The abstract notion of a pattern is introduced, which may be seen as an analogue of the space group of isometries preserving a tiling but where, instead, one considers partial isometries preserving portions of it. These inverse semigroups of partial transformations are the suitable analogue of the space group for patterns with FLC but few global symmetries. In a similar vein we introduce the notion of a collage, a system of equivalence relations on the ambient space of a pattern, which we show is capable of generalising many constructions applicable to the study of FLC tilings and Delone sets, such as the expression of the tiling space as an inverse limit of approximants. An invariant is constructed for our abstract patterns, the so called patternequivariant (PE) homology. These homology groups are defined using infinite singular chains on the ambient space of the pattern, although we show that one may define cellular versions which are isomorphic under suitable conditions. For FLC tilings these cellular PE chains are analogous to the PE cellular cochains [47]. The PE homology and cohomology groups are shown to be related through Poincare duality. An efficient and highly geometric method for the computation of the PE homology groups for hierarchical tilings is presented. The rotationally invariant PE homology groups are shown not to be a topological invariant for the associated tiling space and seem to retain extra information about global symmetries of tilings in the tiling space. We show how the PE homology groups may be incorporated into a spectral sequence converging to the Cech cohomology of the rigid hull of a tiling. These methods allow for a simple computation of the Cech cohomology of the rigid hull of the Penrose tilings.

Chapter 1 examines peer effects in the take up of welfare within a school setting- free school meals. Data from the Pupil Level Annual School Census, which collects information on every child attending a school in the UK, is used, defining the peer group using the child's ethnicity and language. Hypotheses about the nature of the peer effect are tested. I exploit the introduction of cashless catering systems which removes stigma. Secondly, by comparing the peer effect for those who have claimed in previous years with those who have not, information is tested. Finally, I test a role model hypothesis. All three have an impact and information is most important for the most deprived. Chapter 2 examines the casual effect of education on teen births and child health. The increase in school leaving age to 15 and 16 increased the years of completed schooling; however, there was no effect of the introduction of new examinations. The compulsory schooling law change to 16 did increase the probability of holding a qualification and reduced the probability of a teen birth. Furthermore, the impact of the increase to 16 also - lead to improvements in birth outcomes, this was primarily driven by the mother having a more educated partner and a reduction in poverty. Other measures of child health are mixed and mostly did not improve. Chapter 3 (with Michele Belot, published in Journal of Health Economics (2011)) pro- vides field evidence on the effect of diet on educational outcomes, exploiting a campaign lead by celebrity chef J amie Oliver in 2004, which introduced drastic changes in the meals offered in the schools of one Borough - Greenwich - shifting from low-budget processed meals towards healthier options. We evaluate the effect of the campaign on educational outcomes using a difference in differences approach; using the neighbouring Local Edu- cation Authorities as a control group. We find evidence that educational outcomes did improve and that authorised absences - which are most likely linked to illness and health - fell by 14%.

This thesis extends a recent vein of literature which investigates the implications of wage decisions for the optimal design of the monetary regime when the goods market is monopolistically competitive. Chapter II abstracts from the existence of stochastic shocks and examines in detail the resulting macroeconomic wage-setting externality. It points out that when the monetary instrument is set after wage determination, there exists a monetary rule which can induce non-atomistic unions to set the market-clearing nominal wage, and which therefore is fully credible. This result is shown to be implicit in (and to have been overlooked by) previous contributions, and its sensitivity to the precise formulation of the union objective function is discussed. Chapter III allows for stochastic shocks, and in particular builds upon Herrendorf and Lockwood (1997) by assuming that each union receives a (common) noisy signal of a productivity shock prior to setting its individual wage. The adverse macroeconomic externality which arises in this scenario is analysed, and the circumstances under which improvements in signal quality are detrimental to union welfare are identified. It is shown that when unions are nonatomistic, the externality's strength, and hence also both employment variability and the stochastic inflation bias, are sensitive to the specification of the authorities' monetary reaction function. This implies a candidate explanation for why greater central-bank conservatism has generally not been found to be associated with greater output variability. The optimal central-bank delegation arrangements are identified, as well as the optimal amount of transparency regarding supply shocks. Chapters V and VI then analyse the externalities appertaining to indexation decisions taken in the absence of informative signals, both for the standard scenario in which the wage is indexed only to the price level, and for multiparameter indexation scenarios in which the wage is also contingent on a second aggregate variable.

Recombinant DNA technology has allowed the cloning and expression of heterologous proteins in a host cell. Further manipulation of these foreign proteins by genetic engineering allows them to be expressed into the periplasmic space of Escherichia coli. This compartmentalisation of the cell contents exploits a number of key bioprocess advantages. There is a reduction in the process volume, the level of protein and protease contamination is lower, the oxidative environment allows the correct folding of the protein and it is protected from denaturing conditions, such as air-liquid interfaces, during production. However, release from the periplasm at large scale is not straight forward and the balance of advantages and disadvantages can only be assessed by examination of complete processes. This thesis examines some of the process options available for the recovery of selectively released recombinant proteins using a model system comprising E. coli expressing a thermostable α-amylase derived from Streptomyces thermoviolaceus CUB 74. Selective release using lysozyme has been examined with results indicating that the amounts of lysozyme used can be reduced five-fold, from those used in previous studies, to 2.8 mg lysozyme g-1 cells at cell concentrations between 30 to 70 g 1-1. Adjustment of the composition of the periplasmic lysis mixture shows that release was still achieved where no lysozyme use was possible. The possibility of recycling lysozyme for repeated use in periplasmic release was also addressed. The project examines the issues in processing periplasmically secreted recombinant proteins particularly from process liquors that incorporate periplasmic lysis mixtures. Comparison of selective release with homogenisation and secretion, from Streptomyces lividans, was carried out as process alternatives for the recovery of recombinant protein.

The results of an experimental study of phenomena which occur in the flow of a viscous fluid in closed domains with discrete symmetries are presented. The purpose is to investigate the role which ideas from low-dimensional dynamical systems have to play in describing qualitative changes that take place with variation of the governing parameters. Such a descriptive framework already exists for the case of the Taylor-Couette system, where the domain possesses a continuous azimuthal symmetry group. The present investigation is aimed at establishing the typicality of previously reported behaviour under progressive reductions of azimuthal symmetry. In the first investigations, the fixed outer circular cylinder of the standard system is replaced with one of square cross-section. Thus there is now discrete Ζ4 symmetry in the azimuthal direction. Knowledge of the two-dimensional flow field is used to establish the nature of the steady three-dimensional motion equivalent to Taylor vortex flow. It is shown that similar bifurcation sequences exist in both standard and square systems for the case of very small aspect ratio where a single Taylor cell is formed. This flow develops as the result of a bifurcation which breaks the Ζ2 symmetry that is imposed on the annulus by two solid stationary ends. The study is then extended to consider time-dependent effects in the square system. Two different oscillatory single-cell flows are identified, and it is shown that each is the result of a Hopf bifurcation. Selection of a particular dynamic mode is found to depend on the aspect ratio of the system. A low-dimensional bifurcation structure is uncovered which connects the two modes in parameter space, and involves a novel type of steady single-cell flow. Finally, observations are reported of a nontrivial type of dynamical behaviour which bears strong resemblance to motion found in a circularly symmetric Taylor-Couette system that is related to the Šilnikov mechanism for finite-dimensional chaos. A second variant on the Taylor-Couette system is considered where the outer cylinder is shaped like a stadium. The effect is to reduce further the overall symmetry of the domain to a Ζ2 × Ζ2 group. The two-dimensional flow field is investigated using both numerical and experimental techniques. Time-dependent phenomena are then investigated in the three-dimensional flow over a relatively wide range of aspect ratio. It is found that a sequence of a Hopf bifurcation followed by period-doubling bifurcations exists up to a certain aspect ratio, beyond which there is an apparently sudden and reversible transition between regular and irregular dynamical behaviour. Although this transition is not of a low-dimensional nature, the experimental results suggest that it exists as the result of a coalescence of the bifurcations which are found at lower values of aspect ratio.

Greater transparency in policymaking has been a distinct trend among the world's major central banks in the past 30 years. This trend reflects an established view in the central-banking community that managing expectations in the economy through communication is an important element of monetary policy. This view implies that there is an inherent connection between central bank transparency, private sector knowledge, and effectiveness of policy. The aim of this thesis is to add to the theoretical body of work by considering optimal policy design in the context of a narrow set of game-theoretic models with strategic complementarities and heterogeneity in private sector information. Each model variation is defined in terms of assumptions about information quality, its acquisition and dissemination. We evaluate policy performance in terms of social welfare outcomes as well as its ability to eliminate informational inefficiencies. In Chapter 2 we extend the seminal Morris and Shin (2002) model to include information stickiness in the private sector, central bank transparency, and direct policy intervention. We find that in our model (i) commitment performs at least as well as discretionary policy, and (ii) optimally designed policy fails to achieve an efficient outcome. In Chapter 3 we extend the Morris and Shin (2002) model to include costly private information acquisition, central bank transparency, and direct policy intervention. In an economy with a fixed information cost, the combination of full opacity and an optimally designed policy rule achieves efficiency; whereas, in an economy with a linear-cost structure, optimal policy either eliminates or at least mitigates informational inefficiencies. In Chapter 4 we extend the Morris and Shin (2018) market signal model to include costly information acquisition. We consider private and public information acquisition. We look at how information value of private sector actions enters the central banks' optimal commitment strategies.