Angular dependence of the response of the nanoDot OSLD system for measurements at depth in clinical megavoltage beams

Purpose The purpose of this investigation was to assess the angular dependence of a commercial optically stimulated luminescence dosimeter (OSLD) dosimetry system in MV x-ray beams at depths beyondd max and to find ways to mitigate this dependence for measurements in phantoms. Methods Two special holders were designed which allow a dosimeter to be rotated around the center of its sensitive volume. The dosimeter's sensitive volume is a disk, 5 mm in diameter and 0.2 mm thick. The first holder rotates the disk in the traditional way. It positions the disk perpendicular to the beam (gantry pointing to the floor) in the initial position (0°). When the holder is rotated the angle of the disk towards the beam increases until the disk is parallel with the beam (“edge on,” 90°). This is referred to as Setup 1. The second holder offers a new, alternative measurement position. It positions the disk parallel to the beam for all angles while rotating around its center (Setup 2). Measurements with five to ten dosimeters per point were carried out for 6 MV at 3 and 10 cm depth. Monte Carlo simulations using GEANT4 were performed to simulate the response of the active detector material for several angles. Detector and housing were simulated in detail based on microCT data and communications with the manufacturer. Various material compositions and an all-water geometry were considered. Results For the traditional Setup 1 the response of the OSLD dropped on average by 1.4% ± 0.7% (measurement) and 2.1% ± 0.3% (Monte Carlo simulation) for the 90° orientation compared to 0°. Monte Carlo simulations also showed a strong dependence of the effect on the composition of the sensitive layer. Assuming the layer to completely consist of the active material (Al2O3) results in a 7% drop in response for 90° compared to 0°. Assuming the layer to be completely water, results in a flat response within the simulation uncertainty of about 1%. For the new Setup 2, measurements and Monte Carlo simulations found the angular dependence of the dosimeter to be below 1% and within the measurement uncertainty. Conclusions The dosimeter system exhibits a small angular dependence of approximately 2% which needs to be considered for measurements involving other than normal incident beams angles. This applies in particular to clinicalin vivo measurements where the orientation of the dosimeter is dictated by clinical circumstances and cannot be optimized as otherwise suggested here. When measuring in a phantom, the proposed new setup should be considered. It changes the orientation of the dosimeter so that a coplanar beam arrangement always hits the disk shaped detector material from the thin side and thereby reduces the angular dependence of the response to within the measurement uncertainty of about 1%. This improvement makes the dosimeter more attractive for clinical measurements with multiple coplanar beams in phantoms, as the overall measurement uncertainty is reduced. Similarly, phantom based postal audits can transition from the traditional TLD to the more accurate and convenient OSLD.

Community and the Law: A Critical Reassessment of American Liberalism and Japanese Modernity

"This important book translates seven landmark essays by one of Japan’s most respected and influential legal thinkers. While Takao Tanase concedes that law might not matter as much in Japan as it does in the United States, in a provocative challenge to socio-legal researchers and comparative lawyers, he asks: why should it? The issue, he contends, is not whether law matters to society; it is how society matters to law."--Publisher website

Introduction: Japan’s gradual transformation in corporate governance

Japan has recovered from a ‘lost decade’ of economic stagnation over the 1990s. Anyway, it has been a ‘found decade’ for civil and criminal justice law reform, especially in corporate and securities law. Yet, have liberalisation and globalisation in those fields led to major changes in the ‘law in action’? Does this represent ‘Americanisation’ of Japan’s corporate governance system, focusing on shareholders rather than other key stakeholders such as ‘main banks’, core employees, and partners within diffuse corporate groups (keiretsu)? This version of our introductory chapter explains how our forthcoming book argues for a more complex ‘gradual transformation’. Such shifts are also found in many other post-industrial economies, but Japan appears to give greater emphasis given to certain modes of achieving change. The book brings together contributions from academics and practitioners from Japan, Australia, New Zealand, Canada and the United States. An early chapter introduces methodology for effective cross-country comparisons and for evaluating the burgeoning but divergent literature on Japanese corporate governance. The concluding chapter compares continuities and changes in Japan’s largest companies now and two decades ago. Other chapters cover ‘lifelong employment’, main banks, the untold story of closely-held companies, the limited uptake of the Committee-based governance form, and the procedural, substantive and FDI policy dimensions of takeovers law and practice.

The corporate regulation of sexual harassment in Japan

Book Title in Japanese: 雇用・社会保障とジェンダー Chapter Title in Japanese: セクシャル・ハラスメント規制の企業化と男女平等政策への示唆

Japanese women and the ‘new’ administrative state

This chapter questions whether Japanese administrative law reform agenda aimed at promoting greater transparency in decision-making will necessarily lead to better policy outcomes for Japanese women. The chapter evaluates recent legislative reforms and policymaking initiatives in the area of sexual harassment and argues that these developments do not improve the situation for Japanese women. The reason is that the new rules effectively charge corporations with the responsibility to self-regulate, thereby transforming sexual harassment from a public issue of human rights to a domestic issue of corporate governance.

Sexual harassment and the corporation in Australia and Japan: The potential for corporate governance of human rights

The authors explore the legal and social undercurrents in Australia and Japan which are encouraging corporations to embrace broader social responsibilities. They consider a case study of sexual harassment and its regulation within Australian corporations, uncovering the legal and social conditions that have led to the adoption of sexual harassment policies. The authors propose a model for determining when corporate governance of sexual harassment is likely to be effective and test the model by reference to the experience of sexual harassment in Japan. They draw some conclusions about what the experience of corporate implementation of management of sexual harassment might mean for other areas of human rights.

Private governance of public rights in Japan: Revisiting the Japanese governance debate

Dramatic growth in the Japanese economy in the postwar period – and its meltdown in the 1990s – has attracted sustained interest in the power dynamics underlying the management of Japan’s administrative state. For a long time, scholars and commentators have debated about who wields power in Japan. The question has been asked in different ways. In the 1970s and 1980s, the question was usually posed as: who orchestrated Japan’s economic miracle in the 1960s and 1970s? Today, the question is usually reframed to: who is accountable for the policy failures that plunged Japan into financial crisis and recession during the 1990s? Yet the core issue remains the same – who governs Japan? (Johnson 1995)...

Eastern twists on Western concepts: Equality jurisprudence and sexual harassment in Japan

A rich source of Japanese jurisprudence on sexual equality underlies Japan's emerging law against sexual harassment. With no law specifically outlawing sexual harassment, academics and the courts have invoked the principle of sexual equality to support their conclusion that Japanese law carries an implicit prohibition against acts of sexual harassment. In developing a legal case against sexual harassment, Japanese courts and academic commentators have introduced novel constructions of equality. The key innovations include relational equality, inherent equality and quantifiable equality. In presenting some of these Japanese contributions to equality jurisprudence, the hope is that feminist discourse on equality can take place in a broader context-a context that does not ignore the Eastern cultural experience.

Indigenous legal education at UNSW: A work in progress

Since the 1970s Australian law schools have provided alternative entry routes and, since the 1980s, pre-law programs and bridging programs. On-going support, once Indigenous students reach university law schools, has been an issue that has not been formally or appropriately addressed in most university law schools. In this way Indigenous students’ chances of entry are disguised as chances of success. Thus once Indigenous students start their law school studies, they are often expected to perform on a level playing field – their success or failure then depends on ‘gifts, merits or skills’ which are culturally appropriate for law school. This attitude fails to recognise the privilege which allows the development of such gifts, merits or skills...