Laser-driven proton scaling laws and new paths towards energy increase

The past few years have seen remarkable progress in the development of laser-based particle accelerators. The ability to produce ultrabright beams of multi-megaelectronvolt protons routinely has many potential uses from engineering to medicine, but for this potential to be realized substantial improvements in the performances of these devices must be made. Here we show that in the laser-driven accelerator that has been demonstrated experimentally to produce the highest energy protons, scaling laws derived from fluid models and supported by numerical simulations can be used to accurately describe the acceleration of proton beams for a large range of laser and target parameters. This enables us to evaluate the laser parameters needed to produce high-energy and high-quality proton beams of interest for radiography of dense objects or proton therapy of deep-seated tumours.

Area laws and entanglement distillability of thermal states

We study the entanglement distillability properties of thermal states of many-body systems Following the ideas presented in [6, A Ferraro et al., Phys. Rev Lett 100, 080502 (2008)], we first discuss the appearance of bound entanglement in those systems satisfying an entanglement area law Then, we extend these results to other topologies, not necessarily satisfying an entanglement area law We also study whether bound entanglement survives in the macroscopic limit of an infinite number of particles.

Massive MIMO with Non-Ideal Arbitrary Arrays: Hardware Scaling Laws and Circuit-Aware Design

Massive multiple-input multiple-output (MIMO) systems are cellular networks where the base stations (BSs) are equipped with unconventionally many antennas, deployed on colocated or distributed arrays. Huge spatial degrees-of-freedom are achieved by coherent processing over these massive arrays, which provide strong signal gains, resilience to imperfect channel knowledge, and low interference. This comes at the price of more infrastructure; the hardware cost and circuit power consumption scale linearly/affinely with the number of BS antennas N. Hence, the key to cost-efficient deployment of large arrays is low-cost antenna branches with low circuit power, in contrast to today’s conventional expensive and power-hungry BS antenna branches. Such low-cost transceivers are prone to hardware imperfections, but it has been conjectured that the huge degrees-of-freedom would bring robustness to such imperfections. We prove this claim for a generalized uplink system with multiplicative phasedrifts, additive distortion noise, and noise amplification. Specifically, we derive closed-form expressions for the user rates and a scaling law that shows how fast the hardware imperfections can increase with N while maintaining high rates. The connection between this scaling law and the power consumption of different transceiver circuits is rigorously exemplified. This reveals that one can make the circuit power increase as p N, instead of linearly, by careful circuit-aware system design.

Terrorism Laws and Legal Accountability

This chapter explores the extent to which courts can contribute to the countering of terrorism. It suggests that the contribution will depend on the type of actor the courts are attempting to hold to account as well as on the powers that are conferred on courts by national and international legal regimes. It concludes that courts are most legitimate and effective in relation to terrorist suspects and law enforcers, but less so in relation to counter-terrorism operatives and law-makers.

Approved Social Work Training in Northern Ireland: Using Research to Examine Competence-Based Learning and Influence Policy Change

This article reports on how research activity helped describe and analyse ASW (Approved Social Worker) learning experience as well as acting as a catalyst for change and development in policy and practice in Northern Ireland. The paper contextualizes the study by outlining the legislation, the main features of the ASW role and the approach to ASW training in Northern Ireland, and by reviewing the literature on the efficacy and value of competence-based learning. While the findings do not provide conclusive evidence that a competence-based approach is inherently more effective than previous courses, they do indicate that candidates who were trained in this way were moderately more satisfied than those who had participated in non-competence based programmes. The research also highlights the importance of the interrelationship between training, practice experience and support in developing and sustaining competence. The paper concludes with a review of the recommendations arising from the study and an analysis of the developments in training and regulations relating to practice experience and re-approval of ASWs since publication of the research. The study is of contemporary interest given the proposed changes to the role of ASWs/Mental Health Officers in the context of the reviews of UK mental health law.

Any Nearer to Victory in the Fifty Years War?:Assessing the European Commission’s Leadership, Weapons and Strategies towards combating Cartels

Some 50 years after its creation EU competition policy remains firmly entrenched as one of the most developed examples of supranational governance within the European Union. Although there has been a marked increase in interest among political scientists in competition policy in recent years there are still gaps in terms of overall coverage. One area that has been largely overlooked centres on cartels. Cartel policy has emerged as a highly salient issue and main priority of the Commission's competition policy since the late 1990s. Certainly, the recent restructuring of the EU cartel enforcement regime, the imposition of ever higher fines and a determined EU Competition Commissioner have fuelled growing media attention while new notices and regulations increasingly occupy the interests and minds of practitioners. The European Commission has constantly extended its activities on the competition policy front and its increasingly aggressive strategies to combat cartels provides political scientists with a fascinating case study of governance in action and illustrates the ways – such as leniency programmes, higher fines, enhanced and better equipped resources as well as internal reorganisation in which the European regulator is pursuing such conspiracies. This article traces the evolution and development of EU cartel policy since its inception and assesses the Commission's strategies and considers just to what extent the European Commission is winning its war against business cartelisation.

Agitating for a design and regeneration agenda in a postconflict city: the case of Belfast

Introduction

Belfast has been a focus of academic attention for the last forty years with most interest centred on various aspects of ‘the Troubles’. Where there has been interest in the built environment, it has largely been about how the ‘security situation’ impacted directly on architecture and on the design and layout of social housing. This paper seeks to go beyond this to explore how the political- administrative culture of ‘the Troubles’ interacted with ‘normal’ market forces to shape the central area of the city, and to consider the responses of a recently formed activist group, known as the Forum for Alternative Belfast (hereafter referred to as the Forum). The paper is written by three of the directors of the Forum.1 Moreover, the empirical research presented here was undertaken by the Forum as part of a campaign to address issues relating to the design, layout and quality of Belfast’s built environment. In the longstanding tradition of participant observation working within an action-research paradigm, the participants have attempted to offer an account that is evidentially and purposefully selfcritical and reflective. It is of course recognised that while this approach offers many positive attributes, such as phenomenological access through immersion in the project, it also has the potential to bring compromise on research detachment and objectivity.2 To address the latter, the authors have attempted
to avoid polemical argument, and to support claims with primary or secondary research evidence. The authors also acknowledge that action-research has a chequered history; however, they would argue
that their approach is faithful to a concept that sees ‘research’ defined as understanding and ‘action’ defined as seeking change. The Forum’s very purpose is to seek change, but to do this requires evidence, collaboration and demonstration. And in this sense, it is a learning process for all participants, including the research activists, government officials, community organisations and students. The authors also recognise the complexity of factors that affect urban management and change, particularly in a city such as Belfast, which has had to cope with political violence for over thirty years. And they appreciate that in the context of conflict, governance is skewed to cope with political realities. Hamdi reminds us, however, that in practice there is an ‘important dialectic between top-down planning, with its formal and designed laws and structures, and bottom-up selforganizing collectivism—those “quantum and emergent systems” which Jane Jacobs argued long ago give cities their life and order.’3

Modulated wave packets and envelope solitary structures in complex plasmas

A theoretical study is presented of the nonlinear amplitude modulation of waves propagating in unmagnetized plasmas contaminated by charged dust particles. Distinct well-known dusty plasma modes are explicitly considered, namely, the dust-acoustic wave, the dust-ion acoustic wave, and transverse dust-lattice waves. Using a multiple-scale technique, a nonlinear Schrodinger-type equation is derived, describing the evolution of the wave amplitude. A stability analysis reveals the possibility for modulational instability to occur, possibly leading to the formation of different types of envelope-localized excitations (solitary waves), under conditions which depend on the wave dispersion laws and intrinsic dusty plasma parameters.

Reconceptualising Penality: A comparative perspective on punitiveness in Ireland, Scotland and New Zealand

Drastic increases in the use of imprisonment; the introduction of ‘three strikes’ laws and mandatory sentences; restrictions on parole - all of these developments appear to signify a new, harsher era or ‘punitive turn’. Yet these features of criminal justice are not universally present in all Western countries. Drawing on empirical data, Hamilton examines the prevalence of harsher penal policies in Ireland, Scotland and New Zealand, thereby demonstrating the utility of viewing criminal justice from the perspective of smaller jurisdictions.

This highly innovative book is thoroughly critical of the way in which punitiveness is currently measured by leading criminologists. It is essential reading for students and scholars of criminology, penology, criminal justice and socio-legal studies, as well as criminal lawyers and practitioners.

Climate Change, national politics and grassroots action: an introduction

Climate change continues to dominate academic work within green/environmental politics. Indeed, there appears to be almost an inverse relationship between the lack of political leadership on tackling climate change and the growth in ever more sophisticated academic analyses of this complex and multifaceted problem. There is an increasing disjunction between the growth in our knowledge and understanding of the ethical, political, economic, sociological, cultural, and psychological aspects of climate change and the lack of political achievement in putting in place clear and binding targets, an agreed decarbonisation roadmap, and associated regulatory and policy instruments with enforcement. This gap might be taken as evidence that we do not need more reports on climate change. To quote that most unlikely of green politicians, Arnold Schwarzenegger, former Governor of California: ‘The debate is over. We know the science. We see the threat. And we know that the time for action is now’ (California Energy Commission 2007, p. 1). This special issue focuses on a variety of ways in which climate change is conceptualised in normative political and ethical theory, and addressed in policy and regulations.

Queer Spaces, Sexual Violence and the Desire for Safety

Queer politics and spaces have historically been associated with ideals of sexual liberation. They are conceptualised as spaces where sex, and its intersections with intimacy, friendship and love can be explored outside of normative frameworks which value monogamous reproductive heterosexuality at the expense of other non-normative sexual expressions. In recent years, however, autonomous queer spaces such as the global Queeruption gatherings and other queer community spaces in Australia have become increasingly concerned with the presence and danger of sexual violence in queer communities. Almost without exception, this danger has been responded to through the creation of ‘safe(r) spaces’ policies, generally consisting of a set of guidelines and proscribed behaviours which individuals must agree to in order to participate in or attend the event or space. The guidelines themselves tend to privilege of sexual politics of affirmative verbal consent, insisting that such consent should be sought prior to any physical or sexual contact, inferring that a failure to do so is ethically unacceptable within. This chapter reflects on the attempts to construct queer communities as ‘safer spaces,’ arguing that the concepts of consent and safety are inadequate to develop a queer response to sexual violence. Such a response, it argues, must be based on the openness to possibilities and refusal of sexual restrictions and regulations that have always been central elements of queer theory and politics.