Radio Bursts Associated with Flare and Ejecta in the 13 July 2004 Event

We investigate coronal transients associated with a GOES M6.7 class flare and a coronal mass ejection (CME) on 13 July 2004. During the rising phase of the flare, a filament eruption, loop expansion, a Moreton wave, and an ejecta were observed. An EIT wave was detected later on. The main features in the radio dynamic spectrum were a frequency-drifting continuum and two type II bursts. Our analysis shows that if the first type II burst was formed in the low corona, the burst heights and speed are close to the projected distances and speed of the Moreton wave (a chromospheric shock wave signature). The frequency-drifting radio continuum, starting above 1 GHz, was formed almost two minutes prior to any shock features becoming visible, and a fast-expanding piston (visible as the continuum) could have launched another shock wave. A possible scenario is that a flare blast overtook the earlier transient, and ignited the first type II burst. The second type II burst may have been formed by the same shock, but only if the shock was propagating at a constant speed. This interpretation also requires that the shock-producing regions were located at different parts of the propagating structure, or that the shock was passing through regions with highly different atmospheric densities. This complex event, with a multitude of radio features and transients at other wavelengths, presents evidence for both blast-wave-related and CME-related radio emissions.Comment: 14 pages, 6 figures; Solar Physics Topical Issue, in pres

The bioaccumulation testing strategy for manufactured nanomaterials: physico-chemical triggers and read across from earthworms in a meta-analysis

Little is known about the bioaccumulation potential of manufactured nanomaterials (MNs). For traditional chemicals, the Organisation for Economic Co-operation and Development (OECD) Test Guideline (TG) 305, bioaccumulation in fish is often used. However, for MNs, there are no approved processes to trigger or waive this test, or consider alternatives to vertebrate animals. The aim of the present study was to conduct a meta-analysis of existing data sets on particle properties and bioaccumulation in earthworms to understand what particle metrics could be used as a trigger for bioaccumulation testing. An apparent steady state tissue concentration of metal from MNs exposure in the earthworm (Eisenia fetida) was evident following exposures to Ag nanoparticles (NPs), CuO NPs and CdTe quantum dots (QDs). This allowed the derivation of nano bioaccumulation factors (nBAFs), calculated using soil and earthworm tissue metal concentrations. A prediction equation using all the particle metrics correlated with BAFs was possible. Similarly, nano biomagnification factors (nBMFs) were calculated in the rainbow trout (Oncorhynchus mykiss) tissue, relative to the concentration of total metals in the fish diet. Pearson's correlations were found to be significant, with p < 0.05 for nBMFs for the liver, mid intestine, hind intestine and kidney relative to the earthworm tissue nBAFs. Together these data indicate that bioaccumulation measurements in earthworms for metallic MNs could be predictive of those values in fish, and that there is scope to predict the bioaccumulation potential of MNs with confidence from a few simple particle metrics

The governance of co-operatives and mutual associations: a paradox perspective

This paper presents a new theoretical framework for understanding the governance of co-operative and mutual organisations. The theoretical literature on the governance of co-operatives is relatively undeveloped in comparison with that on corporate governance. The paper briefly reviews some of the main theoretical perspectives on corporate governance and discusses how they can be usefully extended to throw light on the governance of co-operatives and mutuals. However, taken individually these different theories are rather one dimensional, only illuminating a particular aspect of the board's role. This has lead to calls for a new conceptual framework that can help integrate the insights of these different theories. The paper argues that a paradox perspective offers a promising way forward. Contrasting the different theoretical perspectives highlights some of the important paradoxes, ambiguities and tensions that boards face

Osmoregulation and Ion Transport: Integrating Physiological Molecular and Environmental Aspects

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Strategic approaches for the management of environmental risk uncertainties posed by nanomaterials

Central to the responsible development of nanotechnologies is an understanding of the risks they pose to the environment. As with any novel material or emerging technology, a scarcity of data introduces potentially high uncertainty in to the characterisation of risk. Early priorities are the identification of key areas of risk uncertainty and the strategic approach for managing and reducing these. This is important as the information subsequently gathered supports decision making and policy development. We identify one important source of uncertainty for the quantification of both hazard and exposure for nanomaterials, the complexity of their behaviour in natural systems. We then outline two approaches for managing this uncertainty, based on experiences with chemicals: one that primarily focuses on hazard and one that initially focuses on exposure. While each approach places emphasis on different information requirements a common feature is the considerable time lag between information gathering and subsequent decision making based on the evidence gathered. Complementary environmental surveillance approaches can act as a safety net, although it is not as yet clear how fit for purpose current monitoring programmes are in this regard

Micronutrient and contaminant limits in aquafeeds

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Conceptions of Work and Learning at Work: Impressions from Older Workers

There is substantial literature on new work practices and the associated skills required of workers in the 'new capitalism' but very few consider workers’ perspectives on the advocacies. The study reported here involved 39 participants aged 40 plus who were interviewed to obtain data in relation to their conceptions of work and learning at work. This was conducted with consideration given to the changing work practices occurring around them. The participants were from a medical service and an engineering organization. The data were analyzed qualitatively and results indicated four and five hierarchical conceptions of work, and learning at work, respectively. It became apparent that a significantly large number of older workers conceived of work and learning at work in quantitative terms and as separate entities. The data were further analysed to ascertain how the conceptions mapped with the participants’ AQF levels. This analysis indicated some dissonance between AQF levels and conceptions. The findings of this study provide baseline data to understand older workers’ behaviours in light of the current changes in work practices