The Origin, Early Evolution and Predictability of Solar Eruptions

Coronal mass ejections (CMEs) were discovered in the early 1970s when space-borne coronagraphs revealed that eruptions of plasma are ejected from the Sun. Today, it is known that the Sun produces eruptive flares, filament eruptions, coronal mass ejections and failed eruptions; all thought to be due to a release of energy stored in the coronal magnetic field during its drastic reconfiguration. This review discusses the observations and physical mechanisms behind this eruptive activity, with a view to making an assessment of the current capability of forecasting these events for space weather risk and impact mitigation. Whilst a wealth of observations exist, and detailed models have been developed, there still exists a need to draw these approaches together. In particular more realistic models are encouraged in order to asses the full range of complexity of the solar atmosphere and the criteria for which an eruption is formed. From the observational side, a more detailed understanding of the role of photospheric flows and reconnection is needed in order to identify the evolutionary path that ultimately means a magnetic structure will erupt

Structural chemistry and electronic properties of Sr₂FeIrO₆

A polycrystalline sample of Sr2FeIrO6 has been synthesized and shown by a combination of X-ray diffraction, neutron diffraction, magnetometry, and Mössbauer spectroscopy to be a triclinic (space group I¯1; a = 5.54996(3) Å, b = 5.57847(3) Å, c = 7.84165(3) Å, α = 89.990(1)°, β = 90.059(1)°, γ = 90.079(1)°) perovskite, with a partially ordered (0.928 : 0.072(4)) distribution of transition metal cations over the six-coordinate sites. The predominant oxidation states are Fe3+ and Ir5+, although the Mössbauer data suggest that ~4% Fe4+ is present. The compound is a Type II antiferromagnet below 120 K, with an ordered magnetic moment on the Fe-dominated sites of 3.67(3) µB per Fe3+ cation. The spins associated with the antisite defects are frustrated and do not take part in the long-range magnetic ordering, consequently giving rise to hysteresis in the magnetic susceptibility below 40 K. The possible location of the Fe4+ cations is discussed briefly.

Occupational safety and health and smaller organisations: research challenges and opportunities

Despite the prevalence of small and medium-sized enterprises (SMEs) and micro organisations, comparatively little is known about how such organisations approach occupational safety and health (OSH). Research has tended to present a negative picture of OSH practices in smaller organisations. This paper discusses some of the challenges to researching OSH in SMEs and micro organisations and how these challenges can be overcome. It draws lessons and experiences from a qualitative study involving 149 structured interviews, nine short-term ethnographies and 21 semi-structured interviews with owners and employees in SMEs and micro organisations from a broad cross-section of industry sectors in the UK, including construction, retail, healthcare, logistics and agriculture. Data from the study suggest that the established boundaries between micro, small and medium-sized enterprises are less meaningful in an OSH context - OSH practices are influenced more by the culture of the organisation, the type of work being undertaken and the sector that an organisation operates in. OSH practices in SMEs and micro organisations tend to reflect more informal characteristics of such organisations, with more emphasis (than many larger organisations) on tacit knowledge, learning by doing and improvisation. Such practices should not necessarily be assumed to be unsafe or incompatible with formalised OSH

Simple does not mean poor: grasslands and forests harbor similar ant species richness and distinct composition in highlands of southern Brazil

Several studies addressed ant communities in the dense Atlantic Forest that runs along the Brazilian coast. However, comparatively little is known about the mixed forests and grasslands that occur in the southern range of the Atlantic Forest domain. In this study we performed the first standardized assessment of ants in the forest- grassland mosaic found in the highlands of the state of Santa Catarina. We aimed to investigate and compare ant richness and composition between mixed forests and grasslands in the main mountain range of south Brazil. Ants were collected in two years with ground pitfalls, tree pitfalls and litter samples. Sixty ant species were recorded, resulting in 22 new records for “Planalto Serrano” region and three for the state of Santa Catarina: Eurhopalothrix depressa , Pheidole radoszkowskii and Wasmannia williamsoni . There was significant dissimilarity in ant species composition between grasslands and forests, but no difference in ant species richness, even considering the higher number of strata in mixed forests. Similar richness and low number of arboreal species suggest that this ant community is structured similarly to temperate ones. Both habitats presented a large proportion of exclusive species. The fact that species composition between grassland and forest areas differed, coupled with the similarity in species richness between habitats and the record of new ant species for the region, calls for strong conservation efforts in grasslands of southern Brazil, which still are little protected by conservation areas