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Magnetic memory and logic technologies promise greater energy efficiency and speed than conventional, semiconductor-based electronics. To date, electrical current has been used to operate such devices, although voltage-control may be a more efficient way to control magnetisation. One route to achieving voltage control of magnetisation is to use a hybrid piezoelectric/ferromagnetic device in which a voltage applied to the piezoelectric induces a strain in the ferromagnetic layer, which in turn induces a magnetic anisotropy. In this thesis such hybrid devices are used to investigate the control of magnetisation by inducing uniaxial anisotropy in the ferromagnetic layer. One material that shows promise for use as the ferromagnetic layer is Fe81Ga19. This material is attractive since it contains no rare earth elements, and in bulk crystals has been shown to be highly magnetically responsive to strain. This thesis investigates the magnetic properties of epitaxial Fe81Ga19 thin films grown by molecular beam epitaxy and it is demonstrated that these thin films retain the attractive magnetostrictive properties previously observed in bulk crystals. The presence of strong cubic magnetocrystalline anisotropy in the layers is exploited to demonstrate the non-volatile switching of magnetisation using strain-induced anisotropy in the absence of an applied magnetic field. This thesis shows also the manipulation of magnetic anisotropies and control of the configuration of magnetic domains and domain walls in Fe81Ga19 at a range of different lateral dimensions, from50 μm to 1 μm. It is shown that as the lateral dimensions of the device structures studied are reduced the domain configuration appears more regular, and that strain-induced anisotropy is more able to control these domains. In wires around 1 μm in width it is shown that growth strain relaxation by lithographic patterning induces sufficient anisotropy to cause a change in the domain configuration of the wire studied. Finally, this thesis begins to investigate how inverse magnetostriction can be used to tune the behaviour of domain walls in wires 1 μm wide and narrower. Experimental control of the field required to depin a vortex domain wall from a notch in a 1 μm wide Co wire is demonstrated. Using micromagnetic simulations it is shown that a large degree of control over the depinning of domain walls from notches in wires 1 μm wide and narrower is possible. The influence of in plane uniaxial magnetic anisotropy on the domain wall velocity in wires supporting in plane transverse domain walls driven by an external magnetic field is also investigated. Work previously done on the effect of uniaxial anisotropy on domain wall velocities close to Walker breakdown is extended in this thesis and in investigating the velocity and structure at driving magnetic fields far above walker Breakdown a second peak in domain wall velocity is observed, a phenomenon previously observed in wide wires, and wires under the influence of a transverse magnetic field.

Paper 1: Examining the views of restorative practitioners about the effects of their professional practices. Abstract The Youth Justice Board and the Department for Education share the common goal of reducing offending and harmful behaviour in children and young people (Ministry of Justice, 2010; DfE, 2011). In both sectors, evidence for the effectiveness of practices based upon the principles of restorative justice (RJ) is mounting, yet there is a distinct lack of theoretical clarity regarding the psychological mechanisms through which such practices work. Moreover, the voice of RJ practitioners is not found in current theoretical propositions. In this paper, eight RJ practitioners, from a mixture of school and youth justice backgrounds, are interviewed about their professional practices. Interview transcripts are thematically analysed in an inductive manner, according to the guidelines set out by Braun & Clarke (2006). Analysis is interpreted in terms of responsive regulation (Braithwaite, 2002; Morrison, 2003), the social learning perspective of Macready (2009) and in terms of cognitive dissonance theory (Festinger, 1957). It is suggested that RJ-based practices, according to the views of professionals, are effective because a) they respond to harm flexibly and after the incident, b) they engage young people in a process of learning social responsibility and c) they provide young people with ways of reducing cognitive dissonance based upon acknowledging and repairing harm, rather than through blaming and denying responsibility. Paper 2: Examining the views of young people about their experiences of restorative justice-based practices. Abstract The Youth Justice Board and the Department for Education share the common goal of reducing offending and harmful behaviour in children and young people (Ministry of Justice, 2010; DfE, 2011). In both sectors, evidence for the effectiveness of practices based upon the principles of restorative justice (RJ) is mounting, yet there is a distinct lack of theoretical clarity regarding the psychological mechanisms through which such practices work. Whilst the voice of young people can be heard in the literature, these have come primarily through surveys and other closed-question response formats. Thus, there is a lack of an in-depth characterisation of young people’s experiences of RJ. In this paper, six young people are interviewed about their experiences of RJ-based practices. Interview transcripts are thematically analysed in an inductive manner, according to the guidelines set out by Braun & Clarke (2006). Analysis is interpreted in terms of Barton’s (2000) Empowerment Model of Restorative Justice (EMRJ) and in terms of responsive regulation (Braithwaite, 2002; Morrison, 2003). It is suggested that RJ-based practices, according to the views of young people, are effective because a) they empower young people in the process of responding to harm and b) they involve responding to harm flexibly and after the incident, providing emotional support and enabling all stakeholders to be open and honest. The implications of both these findings and those from paper 1 are discussed in the context of Aug 2011 riots.

When we make moral judgements and act morally we recognise and respond to reasons that are there whether we recognise them or not. This is the claim defended in this thesis. It has two aspects. The first is that acts of moral judgement aspire, sometimes successfully, to moral knowledge. This is moral cognitivism. The second is that moral truths report reasons for action. In responding appropriately to these reasons we are motivated to action. This is the practicality of morality. Hence, it is claimed, there is a moral reality that we respond to in both cognition and action. Adopting a practical reason approach, I argue that the objectivity and practicality of morality are not in conflict, but are linked by the idea of a practical reason. The moral truths that we can have knowledge of are the truths about the reasons for action that morality provides. I argue for this claim by showing why we should reject Humean ways of thinking about motivation and practical reason and embrace a broadly Kantian account. I argue that this account is compatible with seeing moral reasons as contributory rather than decisive or overriding. I also show how this account enables moral cognitivists to respond convincingly to arguments advanced by non-cognitivists.

This thesis begins in Chapter One with a discussion of the role of electrophilic cyclisation in the synthesis of tetrahydrofurans. Chapter Two begins with a discussion of the synthesis of iodo-olactones, by the iodolactonisation of β-silyloxy-δ-alkenoic acids (Scheme A). It will show how the potential of this chemistry has been expanded by proving the absolute stereochemistry at the iodine centre. Chapter Two goes on to consider the stereospecific synthesis of 2,3,5-trisubstituted iodo-tetrahydrofurans by the related iodo-etherification of homoallylic alcohols (Scheme B). This is facilitated by the use of anhydrous conditions. The synthesis of 2,3,5-trisubstituted iodo-tetrahydrofuranacetic acid esters and 2,3,5-trisubstituted hydroxy-tetrahydrofuranacetic acid esters by the iodocyclisation of geometrically pure (E)- and (Z)-β-hydroxy-δ-alkenoates was then developed and the stereochemical outcome of the reactions was proven (Scheme C). Targets were chosen which illustrated the utility of the key cyclisations of β-hydroxy-δ-alkenoates. Chapter Three discusses the synthesis of muscarine 93. It was chosen to synthesise muscarine from the cyclisation of the (Z)-β-hydroxy-δ-alkenoate 146. This synthesis is particularly versatile as it not only allows the preparation of muscarine itself, but also of various potentially highly biologically active analogues 146a. The second target selected was Goniofufurone 170. Approaches to this molecule will be discussed in Chapter Four. Model work in the synthesis of goniofufurone began with the cyclisation of the (E)-β-hydroxy-δ-alkenoate 53b, which indeed, led to the facile synthesis of the iodolactone 204. However, early attempts to incorporate the natural side chain met with limited success. Chapter Five discusses an approach to the 2-oxabicyclo-2.2.11-heptane ring system, which has been synthesised by the radical cyclisation of various β,y-unsaturated tetrahydrofurans of the general form shown in Scheme D.