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The jack jumper ant (Myrmecia pilosula), a member of the primitive Myrmecia genus of ants, is well known for its aggressive behaviour and painful, sometimes dangerous sting. However, although the ant is well known to Tasmanians, there are few published studies of its biology or ecology. This project is an attempt to address this lack of research and seeks to explore the interaction between humans and jack jumpers by understanding better the preferred habitat of the ant. Two studies were undertaken within the boundaries of the study area: Hobart City Council, Tasmania, Australia. In the first study, jack jumper nests were searched for ten times in transects, in each of the natural vegetation types. Data were collected on the presence or absence of jack jumper nests, vegetation type, vegetation structure, moss cover, bare ground cover, coarse woody debris cover, rock cover, litter cover, litter depth, and distance to nearest tree as well as observations made about each nest that was found. In the second study, residents of Hobart were surveyed using a questionnaire regarding the features of their property and whether they had ever seen a jack jumper nest or ant on their property. They were also asked to outline the circumstances in which they were stung. To analyse the data, thematic analyses, correlation analyses, analysis of variance, Wilcoxon tests, chi-square testing, logistic regression and ordination were used. The results of the study showed that, within the Hobart City Council boundary, jack jumpers are co-extensive with dry eucalypt open woodlands. These warm, dry and relatively open environments provide the ant with a combination of insolation for warmth and vegetation for food resources such as nectar and invertebrate prey. They also utilise the radiative warmth of rocks and dry soil and often enhance their nest’s thermal capacity with decorations of seeds, soil, charcoal, stones, sticks and sometimes small vertebrate bones. In a suburban context the ants are associated with native vegetation whilst utilising cracks in concrete, walls, rockeries, dry dirt and dry grassy areas to construct nests. The suburbs with a significant matrix of native vegetation such as Mt. Nelson, Fern Tree and West Hobart all contain the ants, whereas the heavily built up areas of Battery point and North Hobart do not. Humans are most likely to be stung by a jack jumper ant in their property when carrying out outdoor duties such as gardening or collecting firewood. They may also be stung whilst walking bare foot. A common sense approach should be employed in order to avoid a sting from a jack jumper. For those wishing to live in areas that do not contain the ant, the built up suburbs of Hobart are recommended.

Carrion is a dynamic and nutrient-rich resource that attracts numerous insect species that undergo succession due to the rapid change in the carrion resource. Despite this process being well-understood, few studies have examined resource change as a driver of carrion insect succession, and instead have focused on the effects of time per se, or on coarse, qualitative measures such as decay stage. Here we report on three field succession experiments using pig carcasses and human cadavers encompassing two winters and one summer. We quantified the effects of resource change (measured as total body score, TBS), carrion type, initial carrion mass, ambient temperature, and season on insect species richness and community composition. We found that all variables had an effect on different taxonomic or trophic components of the insect community composition, with the exception of initial carrion mass which had no effect. We found significant positive effects of TBS on beetle species richness and composition, while fly species richness was not significantly affected by TBS, but was by ambient temperature. TBS had a significant positive effect on all trophic groups, while ambient temperature also had a significant positive effect on the necrophages and predator/parasitoids. Our study indicates that resource change, as indicated by TBS, is an important driver of carrion insect species turnover and succession on carrion, and that TBS can provide information about insect ecological patterns on carrion that other temporal measures of change cannot.

© 2020 The Royal Entomological Society 1. The succession of carrion-associated (necrophilous) insects on decomposing carrion is well documented. To exploit the changing nutritious and dynamic resources available throughout the carrion decomposition process, different species colonise and consume carrion in a predictable temporal sequence. The traits of these necrophilous insects should reflect their ecological strategies. Morphological traits of these insects, such as body size and wing size, however, have not previously been examined during active and advanced decomposition. 2. We used fourth-corner multivariate generalised linear models to identify insect community morphological trait patterns and to quantify their change through time on decomposing rabbit carcasses in grassland and woodland environments. 3. We found that larger-bodied species of flies and carrion-specialist beetles were associated with the early stages of decomposition. The morphological traits of ants, in contrast, showed no changes at carcasses through time and instead showed body size differences between grassland and woodland environments. 4. Our findings indicate that specialist flies and beetles that arrive early in the decomposition process possess traits that enable rapid discovery of carrion at a large scale. Generalist beetles and ants do not share this same trait and are instead adapted to locate and consume a wider variety of resources in their preferred habitat type at their local scale. 5. Our results provide insights into the morphological adaptations linked to the ecological strategies of distinct components of carrion insect communities. Further, our results offer insights into the community assembly dynamics that structure the communities of necrophilous insect species.

BACKGROUND: Sudden infant death syndrome (SIDS) is a leading cause of postneonatal mortality. Genetic heart diseases (GHDs) underlie some cases of SIDS. OBJECTIVES: This study aimed to determine the spectrum and prevalence of GHD-associated mutations as a potential monogenic basis for SIDS. METHODS: A cohort of 419 unrelated SIDS cases (257 male; average age 2.7 ± 1.9 months) underwent whole exome sequencing and a targeted analysis of 90 GHD-susceptibility genes. The yield of "potentially informative," ultra-rare variants (minor allele frequency

The chemistry of the halogen species bromine and iodine has a range of impacts on tropospheric composition, and can affect oxidising capacity in a number of ways. However, recent studies disagree on the overall sign of the impacts of halogens on the oxidising capacity of the troposphere. We present simulations of OH and HO₂ radicals for comparison with observations made in the remote tropical ocean boundary layer during the Seasonal Oxidant Study at the Cape Verde Atmospheric Observatory in 2009. We use both a constrained box model, using detailed chemistry derived from the Master Chemical Mechanism (v3.2), and the three-dimensional global chemistry transport model GEOS-Chem. Both model approaches reproduce the diurnal trends in OH and HO₂. Absolute observed concentrations are well reproduced by the box model but are overpredicted by the global model, potentially owing to incomplete consideration of oceanic sourced radical sinks. The two models, however, differ in the impacts of halogen chemistry. In the box model, halogen chemistry acts to increase OH concentrations (by 9.8 % at midday at the Cape Verde Atmospheric Observatory), while the global model exhibits a small increase in OH at the Cape Verde Atmospheric Observatory (by 0.6 % at midday) but overall shows a decrease in the global annual mass-weighted mean OH of 4.5 %. These differences reflect the variety of timescales through which the halogens impact the chemical system. On short timescales, photolysis of HOBr and HOI, produced by reactions of HO₂ with BrO and IO, respectively, increases the OH concentration. On longer timescales, halogen-catalysed ozone destruction cycles lead to lower primary production of OH radicals through ozone photolysis, and thus to lower OH concentrations. The global model includes more of the longer timescale responses than the constrained box model, and overall the global impact of the longer timescale response (reduced primary production due to lower O₃ concentrations) overwhelms the shorter timescale response (enhanced cycling from HO₂ to OH), and thus the global OH concentration decreases. The Earth system contains many such responses on a large range of timescales. This work highlights the care that needs to be taken to understand the full impact of any one process on the system as a whole.

Research into the language socialisation of migrant-background children in new educational contexts has pointed to a complex relationship between language, identity, and social integration. This article helps us to further define this relationship in two main ways. Firstly, through focusing on the specific (and largely neglected) context of the experiences of newly-arrived migrant school children from disadvantaged backgrounds and with little initial command of English, in the East of England, which has in recent years seen a steep rise in the population of children from Eastern Europe in particular. Secondly, through inductive analysis of the pupils’ accounts of their experience in the new environment, the article identifies four key themes which shed light on the overlap between language, identity, and social integration in this context: perceptions of exclusion in the new language environment, the social boundaries of language use, L1 exchange as communicative capital, and languages and identity simulation.

The reaction CH3C(O)O2 +HO2 → CH3C(O)OOH+O2 (Reaction R5a), CH3C(O)OH + O3 (Reaction R5b), CH3 + CO2 + OH + O2 (Reaction R5c) was studied in a series of experiments conducted at 1000 mbar and (293±2) K in the HIRAC simulation chamber. 5 For the first time, products, (CH3C(O)OOH, CH3C(O)OH, O3 and OH) from all three branching pathways of the reaction have been detected directly and simultaneously. Measurements of radical precursors (CH3OH, CH3CHO), HO2 and some secondary products HCHO and HCOOH further constrained the system. Fitting a comprehensive model to the experimental data, obtained over a range of conditions, determined the 10 branching ratios α(R5a) = 0.37±0.10, α(R5b) = 0.12±0.04 and α(R5c) = 0.51±0.12 (errors at 2σ level). Improved measurement/model agreement was achieved using k(R5) = (2.4±0.4)×10−11 cm3 molecule−1 s −1 , which is within the large uncertainty of the current IUPAC and JPL recommended rate coefficients for the title reaction. The rate coefficient and branching ratios are in good agreement with a recent study performed by Groß 15 et al. (2014b); taken together, these two studies show that the rate of OH regeneration through Reaction (R5) is more rapid than previously thought. GEOS-Chem has been used to assess the implications of the revised rate coefficients and branching ratios; the modelling shows an enhancement of up to 5 % in OH concentrations in tropical rainforest areas and increases of up to 10 % at altitudes of 6–8 km above the equator, 20 compared to calculations based on the IUPAC recommended rate coefficient and yield. The enhanced rate of acetylperoxy consumption significantly reduces PAN in remote regions (up to 30 %) with commensurate reductions in background NOx .

Measurements of the radical species OH and HO2 were made using the fluorescence assay by gas expansion (FAGE) technique during a series of night-time and daytime flights over the UK in summer 2010 and winter 2011. OH was not detected above the instrument's 1σ limit of detection during any of the night-time flights or during the winter daytime flights, placing upper limits on [OH] of 1.8 × 106 molecule cm−3 and 6.4 × 105 molecule cm−3 for the summer and winter flights, respectively. HO2 reached a maximum concentration of 3.2 × 108 molecule cm−3 (13.6 pptv) during a night-time flight on 20 July 2010, when the highest concentrations of NO3 and O3 were also recorded. An analysis of the rates of reaction of OH, O3, and the NO3 radical with measured alkenes indicates that the summer night-time troposphere can be as important for the processing of volatile organic compounds (VOCs) as the winter daytime troposphere. An analysis of the instantaneous rate of production of HO2 from the reactions of O3 and NO3 with alkenes has shown that, on average, reactions of NO3 dominated the night-time production of HO2 during summer and reactions of O3 dominated the night-time HO2 production during winter.

The potential for chemistry occurring in cloud droplets to impact atmospheric composition has been known for some time. However, the lack of direct observations and uncertainty in the magnitude of these reactions led to this area being overlooked in most chemistry transport models. Here we present observations from Mt Schmücke, Germany, of the HO2 radical made alongside a suite of cloud measurements. HO2 concentrations were depleted in-cloud by up to 90% with the rate of heterogeneous loss of HO2 to clouds necessary to bring model and measurements into agreement, demonstrating a dependence on droplet surface area and pH. This provides the first observationally derived assessment for the uptake coefficient of HO2 to cloud droplets and was found to be in good agreement with theoretically derived parameterisations. Global model simulations, including this cloud uptake, showed impacts on the oxidising capacity of the troposphere that depended critically on whether the HO2 uptake leads to production of H2O2 or H2O.