Grothendieck quasitoposes

A full reflective subcategory E of a presheaf category [C*,Set] is the category of sheaves for a topology j on C if and only if the reflection preserves finite limits. Such an E is called a Grothendieck topos. More generally, one can consider two topologies, j contained in k, and the category of sheaves for j which are separated for k. The categories E of this form, for some C, j, and k, are the Grothendieck quasitoposes of the title, previously studied by Borceux and Pedicchio, and include many examples of categories of spaces. They also include the category of concrete sheaves for a concrete site. We show that a full reflective subcategory E of [C*,Set] arises in this way for some j and k if and only if the reflection preserves monomorphisms as well as pullbacks over elements of E.Comment: v2: 24 pages, several revisions based on suggestions of referee, especially the new theorem 5.2; to appear in the Journal of Algebr

Regulating Occupational Health and Safety in a Changing Labour Market

Introduction ....From the late 1970s in Australia, and particularly during the 1980s, Australian OHS legislation was significantly reformed . For the purposes of this paper, the most significant changes in the reformed OHS statutes were the introduction of general duty provisions (the content of which was based largely on the common law negligence standard of care), including duties on employers and self-employed persons to ensure the OHS of persons other than employees, and provisions enabling ‘employees’ to have health and safety representatives, and to participate in health and safety committees. While this model is largely based on the twentieth century assumption that labour law is the regulator of employment relationships, in the provisions imposing general duties on employers and self-employed persons in relation to persons other than employees – introduced ostensibly to protect ‘the public’ from workplace hazards – there was the potential to interpret the duty as applying to workers other than employees

Turning on the alarm: the neural mechanisms of the transition from innocuous to painful sensation

The experience of pain occurs when the level of a stimulus is sufficient to elicit a marked affective response, putatively to warn the organism of potential danger and motivate appropriate behavioral responses. Understanding the biological mechanisms of the transition from innocuous to painful levels of sensation is essential to understanding pain perception as well as clinical conditions characterized by abnormal relationships between stimulation and pain response. Thus, the primary objective of this study was to characterize the neural response associated with this transition and the correspondence between that response and subjective reports of pain. Towards this goal, this study examined BOLD response profiles across a range of temperatures spanning the pain threshold. 14 healthy adults underwent functional magnetic resonance imaging (fMRI) while a range of thermal stimuli (44-49oC) were applied. BOLD responses showed a sigmoidal profile along the range of temperatures in a network of brain regions including insula and mid- cingulate, as well as a number of regions associated with motor responses including ventral lateral nuclei of the thalamus, globus pallidus and premotor cortex. A sigmoid function fit to the BOLD responses in these regions explained up to 85% of the variance in individual pain ratings, and yielded an estimate of the temperature of steepest transition from non-painful to painful heat that was nearly identical to that generated by subjective ratings. These results demonstrate a precise characterization of the relationship between objective levels of stimulation, resulting neural activation, and subjective experience of pain and provide direct evidence for a neural mechanism supporting the nonlinear transition from innocuous to painful levels along the sensory continuum

The OHS regulatory challenges posed by agency workers: evidence From Australia

Labour leasing or agency labour (also known as labour hire in Australia and New Zealand) is a rapidly growing work arrangement in most if not all industrialized countries. Unlike the two-party employer/employee relationship, labour leasing establishes a three-party or triangular relationship between the worker, the agency that supplies them and the host employer. There is emerging evidence that this triangular relationship, in combination with the temporary nature of most placements, poses particular problems for laws regulating employment conditions (industrial relations, occupational health and safety (OHS), and workers’ compensation/social security) and the agencies administering them. This paper examines recent Australian experience with regard to protecting the health and safety of agency workers, drawing on detailed interviews and workplace visits with inspectors, as well as analysis of statutory provisions, documentary records (such as reports and guidance material), and enforcement activity (notably prosecutions) by OHS agencies

Gaelic Learners in the Primary School (GLPS) in Argyll & Bute, East Ayrshire, North Lanarkshire, Perth & Kinross and Stirling : Evaluation Report

For many years individual primary school teachers have no doubt sought to provide their pupils with a brief initial introduction to Gaelic language and culture. However, as a planned, systematic policy development across schools, backed by local authority and national support, GLPS (Gaelic learners in the primary school) has only come into being in the past three years. Thus far it has been taken up in a small number of local authorities, including the five which have commissioned the present evaluation (Argyll & Bute, East Ayrshire, North Lanarkshire, Perth & Kinross, Stirling), but it is attracting interest in a number of others

Take me to your employer: the organisational reach of occupational health and safety regulation

[Conclusion] We have explored two dimensions of the Australian OHS statutes which enable statutory OHS duties to reach more than one employer or self-employed person within a corporate group or network. First, most of the OHS statutes contain provisions extending the reach of employer’s duty beyond the employer’s employees. One legislative technique is to deem contractors and their employees to be employees of the principal contractor. Another imposes duties on employers and self-employed persons to persons who are not employees, so that employers and self-employed persons can be responsible for the OHS of firms, and those they engage, lower in the contractual chain. These duties are non-delegable, meaning that the principal contractor cannot seek to delegate OHS duties to firms lower in the contractual chain. Second, new Victorian ‘shadow officer’ provisions can be applied to remove difficulties and doubt as to the liability of partners in a partnership, officers of unincorporated associations, joint venturers, and holding and subsidiary companies within corporate groups. While the provisions can be argued simply to confirm that a partner who fails to take reasonable care in relation to OHS will be guilty of an offence, we demonstrate that there are very real benefits to having ‘shadow officer’ provisions which remove uncertainties about the liability of unincorporated associations, joint ventures and corporate groups. Perhaps most significantly, the Victorian corporate officer provisions have the potential to extend liability to individuals and other entities within organisational structures, where those individuals and entities make or participate in making decisions that affect the whole or a substantial part of the organisation’s business, and are responsible for an OHS offence having been committed, due to their failure to take reasonable care. We suggest that similar provisions should be included in all OHS statutes, to overcome at least some of the barriers limiting group responsibility for OHS statutory duties

Partners in Excellence : Evaluation Report

This is the final report on the 'Partners in Excellence' initiative, which was funded by the Scottish government, and aimed at increasing motivation for language learning in the upper secondary school, using a variety of stimulants including the use of new technologies. The evaluation draws together the findings from four previous interim reviews, focussing on student and teacher perceptions of the Partners in Excellence initiative

An investigation into a denial of service attack on an ethereum network

Apart from its much-publicised use in crypto-currency, blockchain technology is used in a wide range of application areas, from diamonds to wine. The most common application of this technology is in smart contracts in supply chain management, where assurance of delivery and provenance are important. One problem for an Ethereum consortium is the potential for disruption caused by a Denial-of-Service attack across the consortium nodes. Such an attack can be launched from a single source or multiple sources to amplify the effect. This paper investigates the impact of various Denial-of-Service attacks on an Ethereum Consortium deployed on the Azure Cloud platform. Our experiments demonstrated that a Denial-of-Service attack on some nodes can be successful. We found that an Ethereum Transaction Server is vulnerable to both Flood and Bandwidth Depletion attacks, but that Ethereum Mining Server nodes appear to be resilient to a Bandwidth Depletion attack

Reflection on reforms: developing criminal accountability for industrial deaths

Providing Context: The criminal law has numerous aims, often cited in introductory textbooks to include promoting justice, providing norms to reduce unacceptable social behaviour, achieving deterrence or preventing crime, promoting rehabilitation for the law breaker, providing retribution against the law breaker, expressing moral concern at social harms (denunciation) and enabling appropriate levels of accountability. The criminal justice system is seen as a system providing meaning, achieving goals, and having a purpose rooted within the very foundations of all social and legal systems and ways of life. This paper deals with the application of the criminal law to death as a result of industrial activity (industrial deaths are taken here to refer to traumatic and sudden workplace deaths and deaths in public disasters). It discusses organisational accountability for industrial deaths through examining reform processes in three countries: Australia, Canada and England and Wales