A practical and theoretical definition of 'small field'

Introduction The consistency of measuring small field output factors is greatly increased by reporting the measured dosimetric field size of each factor, as opposed to simply stating the nominal field size [1] and therefore requires the measurement of cross-axis profiles in a water tank. However, this makes output factor measurements time consuming. This project establishes at which field size the accuracy of output factors are not affected by the use of potentially inaccurate nominal field sizes, which we believe establishes a practical working definition of a ‘small’ field. The physical components of the radiation beam that contribute to the rapid change in output factor at small field sizes are examined in detail. The physical interaction that dominates the cause of the rapid dose reduction is quantified, and leads to the establishment of a theoretical definition of a ‘small’ field. Methods Current recommendations suggest that radiation collimation systems and isocentre defining lasers should both be calibrated to permit a maximum positioning uncertainty of 1 mm [2]. The proposed practical definition for small field sizes is as follows: if the output factor changes by ±1.0 % given a change in either field size or detector position of up to ±1 mm then the field should be considered small. Monte Carlo modelling was used to simulate output factors of a 6 MV photon beam for square fields with side lengths from 4.0 to 20.0 mm in 1.0 mm increments. The dose was scored to a 0.5 mm wide and 2.0 mm deep cylindrical volume of water within a cubic water phantom, at a depth of 5 cm and SSD of 95 cm. The maximum difference due to a collimator error of ±1 mm was found by comparing the output factors of adjacent field sizes. The output factor simulations were repeated 1 mm off-axis to quantify the effect of detector misalignment. Further simulations separated the total output factor into collimator scatter factor and phantom scatter factor. The collimator scatter factor was further separated into primary source occlusion effects and ‘traditional’ effects (a combination of flattening filter and jaw scatter etc.). The phantom scatter was separated in photon scatter and electronic disequilibrium. Each of these factors was plotted as a function of field size in order to quantify how each affected the change in small field size. Results The use of our practical definition resulted in field sizes of 15 mm or less being characterised as ‘small’. The change in field size had a greater effect than that of detector misalignment. For field sizes of 12 mm or less, electronic disequilibrium was found to cause the largest change in dose to the central axis (d = 5 cm). Source occlusion also caused a large change in output factor for field sizes less than 8 mm. Discussion and conclusions The measurement of cross-axis profiles are only required for output factor measurements for field sizes of 15 mm or less (for a 6 MV beam on Varian iX linear accelerator). This is expected to be dependent on linear accelerator spot size and photon energy. While some electronic disequilibrium was shown to occur at field sizes as large as 30 mm (the ‘traditional’ definition of small field [3]), it has been shown that it does not cause a greater change than photon scatter until a field size of 12 mm, at which point it becomes by far the most dominant effect.

The value of respect in human research ethics: A conceptual analysis and a practical guide

In order to continue to maintain public trust and confidence in human research, participants must be treated with respect. Researchers and Human Research Ethics Committee members need to be aware that modern considerations of this value include: the need for a valid consenting process, the protection of participants who have their capacity for consent compromised; the promotion of dignity for participants; and the effects that human research may have on cultures and communities. This paper explains the prominence of respect as a value when considering the ethics of human research and provides practical advice for both researchers and Human Research Ethics Committee members in developing respectful research practices.

Practical Advice for Entrepreneurs

I am interested in the psychology of entrepreneurship—how entrepreneurs think, decide to act, and feel. I recently realized that while my publications in academic journals have implications for entrepreneurs, those implications have remained relatively hidden in the text of the articles and hidden in articles published in journals largely inaccessible to those involved in the entrepreneurial process. This book is designed to bring the practical implications of my research to the forefront. I decided to take a different approach with this book and not write it for a publisher. I did this because I wanted the ideas to be freely available: (1) I wanted those interested in practical advice for entrepreneurs to be able to freely download, distribute, and use this information (I only ask that the content be properly cited), (2) I wanted to release the chapters independently and make chapters available as they are finished, and; (3) I wanted this work to be a dialogue rather than a one-way conversation—I hope readers email me feedback (positive and negative) so that I can use this information to revise the book. In producing the journal articles underpinning this book, I have had the pleasure of working with many talented and wonderful colleagues—they are cited at the end of each chapter. I hope you find some of the advice in this book useful.

National and state-level politics on social media : Twitter, Australian political discussions, and the online commentariat

This paper examines the use of Twitter for long-term discussions around Australian politics, at national and state levels, tracking two hashtags during 2012: #auspol, denoting national political topics, and #wapol, which provides a case study of state politics (representing Western Australia). The long-term data collection provides the opportunity to analyse how the Twitter audience responds to Australian politics: which themes attract the most attention and which accounts act as focal points for these discussions. The paper highlights differences in the coverage of state and national politics. For #auspol, a small number of accounts are responsible for the majority of tweets, with politicians invoked but not directly contributing to the discussion. In contrast, #wapol stimulates a much lower level of tweeting. This example also demonstrates that, in addition to citizen accounts, traditional participants within political debate, such as politicians and journalists, are among the active contributors to state-oriented discussions on Twitter.

Reconnecting theory and practice in a pluralistic organizing context : issues and Aristotelian considerations

The overall purpose of this paper is to contribute to the theory - practice gap debate in organization studies, especially in pluralistic contexts such as project organizing. We briefly outline some of the current debates, i.e. modernist and postmodernist proposals, and the prevalent dichotomous thinking stance assumptions to better move beyond it, anchoring our contribution in the Aristotelian ethical and practical philosophy. We introduce the current state of the debate, part of the broad question of “science that matters”, and the various discourses between practice and academia within social sciences and more specifically organizational studies. We briefly critically summarize some main features of the two main philosophical stances (modernism, postmodernism), before presenting some key aspects, for the purpose of this paper, of the Aristotelian pre-modern practical and ethical philosophy. Then, we build on the foundations above established, discussing propositions to reconnect theory and practice according the Aristotelian ethical and practical philosophy, and some key implications for research notably in the following areas: roles played by practitioners and scholars, emancipatory praxeological style of reasoning, for closing the “phronetic gap” and reconnecting means and ends, facts and values, relation between collective praxis, development of “good practice” (standards), ethics and politics. We conclude highlighting the role of the suggested shift to an Aristotelian emancipatory style of reasoning for reconciling theory and practice.

The 3rd Knowledge Cities World Summit Proceedings

FROM KCWS 2010 Ch airs and Summit Proceeding Ed ito rs ‘Knowledge’ is a resource, which relies on the past for a better future. In the 21st century, more than ever before, cities around the world depend on the knowledge of their citizens, their institutions and their firms and enterprises. The knowledge image, the human competence and the reputation of their public and private institutions and corporations profiles a city. It attracts investment, qualified labour and professionals, as well as students and researchers. And it creates local life spaces and professional milieus, which offer the quality of life to the citizens that are seeking to cope with the challenges of modern life in a competitive world. Integrating knowledge-based development in urban strategies and policies, beyond the provision of schools and locations for higher education, has become a new ambitious arena of city politics. Coming from theory to practice, and bringing together the manifold knowledge stakeholders in a city and preparing joint visions for the knowledge city is a new challenge for city managers, urban planners and leaders of the civic society . It requires visionary power, creativity, holistic thinking, the willingness to cooperate with all groups of the local civil society, and the capability to moderate communication processes to overcome conflicts and to develop joint action for a sustainable future. This timely Melbourne 2010 – The Third Knowledge City World Summit makes an important reminder that ‘knowledge’ is the key notion in the 21st Century development. Considering this notion, the summit aims to shed light on the multi-faceted dimensions and various scales of building the ‘knowledge city’ and on ‘knowledge-based development’ paradigms. At this summit, the theoretical and practical maturing of knowledge-based development paradigms will be advanced through the interplay between the world’s leading academic’s theories and the practical models and strategies of practitioners’ and policy makers’ drawn from around the world. As chairs of The Melbourne 2010 Summit, we have compiled this summit proceeding in order to disseminate the knowledge generated and shared in Melbourne with the wider research, governance, and practice communities. The papers in the proceedings reflect the broad range of contributions to the summit. They report on recent developments in planning and managing knowledge cities and ICT infrastructure, they assess the role of knowledge institutions in regional innovation systems and of the intellectual capital of cities and regions; they describe the evolution of knowledge-based approaches to urban development in differing cultural environments; they finally bridge the discourse on the knowledge city to other urban development paradigms such as the creative city, the ubiquitous city or the compact city. The diversity of papers presented shows how different scholars from planning cultures around the world interpret the knowledge dimension in urban and regional development. All papers of this proceeding have gone through a double-blind peer review process and been reviewed by our summit editorial review and advisory board members. We cordially thank the members of the Summit Proceeding Editorial Review and Advisory Board for their diligent work in the review of the papers. We hope the papers in this proceeding will inspire and make a significant contribution to the research, governance, and practice circles.

The IHR (2005), disease surveillance, and the individual in global health politics

Since the revisions to the International Health Regulations (IHR) in 2005, much attention has turned to two concerns relating to infectious disease control. The first is how to assist states to strengthen their capacity to identify and verify public health emergencies of international concern (PHEIC). The second is the question of how the World Health Organization (WHO) will operate its expanded mandate under the revised IHR. Very little attention has been paid to the potential individual power that has been afforded under the IHR revisions – primarily through the first inclusion of human rights principles into the instrument and the allowance for the WHO to receive non-state surveillance intelligence and informal reports of health emergencies. These inclusions mark the individual as a powerful actor, but also recognise the vulnerability of the individual to the whim of the state in outbreak response and containment. In this paper we examine why these changes to the IHR occurred and explore the consequence of expanding the sovereignty-as-responsibility concept to disease outbreak response. To this end our paper considers both the strengths and weaknesses of incorporating reports from non-official sources and including human rights principles in the IHR framework.

Redundant or essential? How politics shaped the outcome of the 1967 Protocol

The 1967 Protocol Relating to the Status of Refugees has been described as an unnecessary addendum to the 1951 Convention Relating to the Status of Refugees. However, if the 1967 Protocol was superfluous, why did the United Nations High Commissioner for Refugees in the early 1960s insist on its development? This article seeks to establish that the 1967 Protocol was originally intended to encompass the broader concerns of African and Asian states concerning refugee populations in their region. However, the political influence upon the development of international refugee law radically altered the UNHCR's endeavour to make the 1951 Convention universally accessible.

The international politics of disease reporting : towards post-Westphalianism?

Since the outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003, there has been much discussion about whether the international community has moved into a new post-Westphalian era, where states increasingly recognize certain shared norms that guide what they ought to do in responding to infectious disease outbreaks. In this article I identify this new obligation as the ‘duty to report’, and examine competing accounts on the degree to which states appreciate this new obligation are considered by examining state behaviour during the H5N1 human infectious outbreaks in East Asia (since 2004). The article examines reporting behaviour for H5N1 human infectious cases in Cambodia, China, Indonesia, Thailand and Vietnam from 2004 to 2010. The findings lend strong support to the claim that East Asian states have come to accept and comply with the duty to report infectious disease outbreaks and that the assertions of sovereignty in response to global health governance frameworks have not systematically inhibited reporting compliance.

Global Politics of Health

International responses to the outbreak of SARS, the spread of HIV/AIDS, and the promotion of health as a human right all demonstrate how global politics have a profound effect on the way we think about and respond to major health challenges. Despite a growing interest in the relationship between health and international relations there has yet to be a systematic study of the links between them. Global Health Issues aims to fill this gap – ultimately showing how world politics can be good, or bad, for your health. This book calls for a more nuanced understanding of the nature of the current global health crisis and the political dilemmas faced by those responsible for the development and implementation of responses to it. By charting these debates and showing how they shape the way actors think about key issues relating to health, such as people movement; infectious disease; the business of health; and the consequences of war; this volume provides an innovative and comprehensive introduction to health and international relations for students of global politics, health studies and related disciplines.

Plasma nanoscience : from controlled complexity to practical simplicity

Plasma Nanoscience is a multidisciplinary research field which aims to elucidate the specific roles, purposes, and benefits of the ionized gas environment in assembling and processing nanoscale objects in natural, laboratory and technological situations. Compared to neutral gas-based routes, in low-temperature weakly-ionized plasmas there is another level of complexity related to the necessity of creating and sustaining a suitable degree of ionization and a much larger number of species generated in the gas phase. The thinner the nanotubes, the stronger is the quantum confinement of electrons and more unique size-dependent quantum effects can emerge. Furthermore, due to a very high mobility of electrons, the surfaces are at a negative potential compared to the plasma bulk. Therefore, there are non-uniform electric fields within the plasma sheath. The electric field lines start in the plasma bulk and converge to the sharp tips of the developing one-dimensional nanostructures.

Part 3. MOO methods for multidisciplinary design using parallel evolutionary algorithms, game theory and hierarchical topology. (Part 3.) Practical application to the design and optimisation of UAV systems

These lecture notes highlight some of the recent applications of multi-objective and multidisciplinary design optimisation in aeronautical design using the framework and methodology described in References 8, 23, 24 and in Part 1 and 2 of the notes. A summary of the methodology is described and the treatment of uncertainties in flight conditions parameters by the HAPEAs software and game strategies is introduced. Several test cases dealing with detailed design and computed with the software are presented and results discussed in section 4 of these notes.

Before and after the creative city : the politics of urban cultural policy in Austin, Texas

This article examines the politics and practice of urban cultural policy in Austin, Texas. I demonstrate how aspects of the local context frame how local government and cultural sector interests strive to initiate the direction of policy. While larger trends—such as Richard Florida's creative city thesis—influence cultural policy and planning, specific contextual factors including prior economic development and growth management policy, departmental organization, the forum for interaction between municipal actors and non-governmental coalitions, and the character of the city's cultural economy mediate such trends to produce policy outcomes. As this case shows, contemporary urban cultural policy is not simply due to the rise of the creative city discourse, but is an evolving product of past policy structures and shaped by local institutions and actors.

Ethics in project management : some Aristotelian insights

Purpose My aim is to introduce, in the project management field, an Aristotelian ethics lens moving beyond the classical deontological and consequentialism approaches underlying the current ethical practices and codes of ethics and professional conducts. In doing so, I wish to pose the premises of a debate on the implications of a conscious ethical perspective for the structure and agency relationship within the project management field Design/methodology/approach Project management is a knowledge field on its own right. However the current perspectives applied to make sense and develop the field (modernism vs. postmodernism) leads to dichotomous thinking rather than recognizing the merits and contextual validity of both sides. I call for Aristotelian Ethics as a way of moving beyond this dichotomous thinking. I introduce briefly Aristotelian Ethics and its consequences in term of relation theory – practice, means and ends, facts and values, and finally politics (i.e. being part of a community of practitioners). Then I illustrate some consequences for the field taking PMI Code of Ethics and Professional Conduct and APM Code of Professional Conduct as supports for discussion Findings I suggest a need for revisiting and/or redesigning the codes of ethics and professional conducts for project management according to an Aristotelian perspective, in order to move beyond the normative limitations of classical deontological (conflict between competing duties, exemplified by PMI Code) or consequentialism (focusing on the "right" outcome to the detriment of duties, exemplified by APM Code) approaches (both, in fact, leading to a disconnection means and ends, and facts and values). This implicates shifting our view from the question "what is my duty?" to the questions "why should I undertake my duty?" and "how ought I act in this situation?" Practical implications Raising Professional Bodies, Industry and Education institutions awareness and consciousness and leading them to rethink about codes of ethics and the implications for the way they conceive practice and research, bodies of knowledge, credentialing, education... Originality/value To the best of my knowledge, this kind of discussion has not yet been conducted within the project management field, and considering the implication of project management in our life and for the well being of the society, an ethical debate may present some value(s)

The Politics of Urban Cultural Policy : Global Perspectives

The Politics of Urban Cultural Policy brings together a range of international experts to critically analyze the ways that governmental actors and non-governmental entities attempt to influence the production and implementation of urban policies directed at the arts, culture, and creative activity. Presenting a global set of case studies that span five continents and 22 cities, the essays in this book advance our understanding of how the dynamic interplay between economic and political context, institutional arrangements, and social networks affect urban cultural policy-making and the ways that these policies impact urban development and influence urban governance. The volume comparatively studies urban cultural policy-making in a diverse set of contexts, analyzes the positive and negative outcomes of policy for different constituencies, and identifies the most effective policy directions, emerging political challenges, and most promising opportunities for building effective cultural policy coalitions. The volume provides a comprehensive and in-depth engagement with the political process of urban cultural policy and urban development studies around the world. It will be of interest to students and researchers interested in urban planning, urban studies and cultural studies.