To sonicate or not to sonicate PM filters: Reactive Oxygen Species generation upon ultrasonic irradiation

In aerosol research, a common approach for the collection of particulate matter (PM) is the use of filters in order to obtain sufficient material to undertake analysis. For subsequent chemical and toxicological analyses, in most of cases the PM needs to be extracted from the filters. Sonication is commonly used to most efficiently extract the PM from the filters. Extraction protocols generally involve 10 - 60 min of sonication. The energy of ultrasonic waves causes the formation and collapse of cavitation bubbles in the solution. Inside the collapsing cavities the localised temperatures and pressures can reach extraordinary values. Although fleeting, such conditions can lead to pyrolysis of the molecules present inside the cavitation bubbles (gases dissolved in the liquid and solvent vapours), which results in the production of free radicals and the generation of new compounds formed by reactions with these free radicals. For example, simple sonication of pure water will result in the formation of detectable levels of hydroxyl radicals. As hydroxyl radicals are recognised as playing key roles as oxidants in the atmosphere the extraction of PM from filters using sonication is therefore problematic. Sonication can result in significant chemical and physical changes to PM through thermal degradation and other reactions. In this article, an overview of sonication technique as used in aerosol research is provided, the capacity for radical generation under these conditions is described and an analysis is given of the impact of sonication-derived free radicals on three molecular probes commonly used by researchers in this field to detect Reactive Oxygen Species in PM.

That’s Not For Our Kids: The strange death of philosophy and ethics in a low socioeconomic secondary school

This article reflects on the successes and failures of a new Philosophy and Ethics course in a low socioeconomic context in Perth, Western Australia, with the eventual demise of the subject in the school at the end of 2010. We frame this reflection within Deleuzian notions of geophilosophy to advocate for a Philosophy and Ethics that is informed by nomadic thought, as this offers a critical freedom for students to transform themselves and their society and suggests practical ways both of overcoming the prejudices which led to its demise and of student reluctance to engage in open discussion in class. We consider the demise of the course a ‘missed opportunity’ because it had so much potential to be transformative of student subjectivities in schools.

Not so not-for-profit

To address the sub-theme of the journal: Artistic Practices in a Time of Crisis, the author discusses the context of economic cuts and recent international crises on his PhD interactive and visual design research project undertaken in Australia. Identifying an apparent root-cause of current global crises, the author in reply, has structured a research plan and created a suite of new media, interactive, technology artworks, and installation art. Notions of Zen Buddhism, and stillness through meditation, are applied in the research and context of the artworks to support awareness of wellbeing, in response to the root-cause condition. The discussion will focus on the overarching question: how can one obtain value through the arts during current times of economic reduction conditioning?

Getting mad may not mean getting even: The influence of drivers' ethical ideologies on driving anger and related behaviour

The current study explored the influence of moral values (measured by ethical ideology) on self-reported driving anger and aggressive driving responses. A convenience sample of drivers aged 17-73 years (n = 280) in Queensland, Australia, completed a self-report survey. Measures included sensation seeking, trait aggression, driving anger, endorsement of aggressive driving responses and ethical ideology (Ethical Position Questionnaire, EPQ). Scores on the two underlying dimensions of the EPQ idealism (highI/lowI) and relativism (highR/lowR) were used to categorise drivers into four ideological groups: Situationists (highI/highR); Absolutists (highI/lowR); Subjectivists (lowI/highR); and Exceptionists (lowI/lowR). Mean aggressive driving scores suggested that exceptionists were significantly more likely to endorse aggressive responses. After accounting for demographic variables, sensation seeking and driving anger, ethical ideological category added significantly, though modestly to the prediction of aggressive driving responses. Patterns in results suggest that those drivers in ideological groups characterised by greater concern to avoid affecting others negatively (i.e. highI, Situationists, Absolutists) may be less likely to endorse aggressive driving responses, even when angry. In contrast, Subjectivists (lowI, HighR), reported the lowest levels of driving anger yet were significantly more likely to endorse aggressive responses. This provides further insight into why high levels of driving anger may not always translate into more aggressive driving.

Curious hybrids: Creating 'not-quite' beings to explore possible childhoods

Communications between adults and young children can expose different ideas and opinions. Adults and children have different capacities to speak, these discursive spaces can become filled with assumptions, stereotyping and conventional thinking about power and agency. If communication shifts away from the purely discursive, what might be exposed about the explorations, investigations and fantasies adults and children indulge in? Some time ago my young daughter obsessively drew hybrid beings. Created from mixtures of animal, object, human and creature forms, these beings, which are ‘not-quite’, are becoming, able to transform via myriad mutations. We agreed to collaborate and draw additional hybrid beings to experiment with becoming-other through complex entanglements of forms, to complicate, morph and (trans)form from our human selves to hybrid others. The ‘not- quite-ness’ of our monstrous hybrids subvert the conventions of ‘being’ and prompt contemplations about childhood subjectivities, identities, conventionalities and actively interrogate the assumptive knowledges and subjectifications that are held about young children in early childhood professional and academic systems.

Determination of preventive maintenance lead time using hybrid analysis

The time for conducting Preventive Maintenance (PM) on an asset is often determined using a predefined alarm limit based on trends of a hazard function. In this paper, the authors propose using both hazard and reliability functions to improve the accuracy of the prediction particularly when the failure characteristic of the asset whole life is modelled using different failure distributions for the different stages of the life of the asset. The proposed method is validated using simulations and case studies.