1.2 Three cardinal numbers to safeguard bees against pesticide exposure: LD50 , NOEC (revised) and the Haber exponent.

Regulators often employ cardinal indicators to justify measures to protect the health of farmland bees from pesticides used in crop protection. Previously, in evaluating the likely hazard of a compound, they have made extensive use of its LD50 (‘lethal dose to 50% of exposed subjects’), and NOEC (‘no observable effect concentration’). Here, I argue that regulators should also use a third indicator, namely the Haber exponent. The Haber exponent qualifies the meaning of the LD50 by revealing the relative hazard of environmentally relevant exposures longer than that used to determine the LD50 originally. Additionally, I show how the experimental protocol used to determine the Haber exponent will also produce a well-founded, parametric value of the NOEC. Taken together, these three numbers establish a strong foundation on which to evaluate the potential impact of an agrochemical on bees.Regulators often employ cardinal indicators to justify measures to protect the health of farmland bees from pesticides used in crop protection. Previously, in evaluating the likely hazard of a compound, they have made extensive use of its LD50 (‘lethal dose to 50% of exposed subjects’), and NOEC (‘no observable effect concentration’). Here, I argue that regulators should also use a third indicator, namely the Haber exponent. The Haber exponent qualifies the meaning of the LD50 by revealing the relative hazard of environmentally relevant exposures longer than that used to determine the LD50 originally. Additionally, I show how the experimental protocol used to determine the Haber exponent will also produce a well-founded, parametric value of the NOEC. Taken together, these three numbers establish a strong foundation on which to evaluate the potential impact of an agrochemical on bees

Predicted thresholds for natural vegetation cover to safeguard pollinator services in agricultural landscapes

This is the author accepted manuscriptThe conversion of natural vegetation into cultivated land can cause pollinator declines and thereby degrade pollination services to crops and wildflowers. The effect of landscape composition on pollinator abundance is well established, but its impact on pollination intensity and crop yield is not fully resolved. We therefore studied pollination of two crops in India, brinjal (Solanum melongena) and mustard (Brassica nigra), along a landscape-scale gradient in habitat transformation from forest-dominated natural vegetation to intensive cultivation. We quantified the pollination requirements (pollen receipt-seed set relationships) of the crops and the levels of pollen delivery by their principal pollinators, bees. Combining these with field surveys of pollinator abundance, we modelled the levels of pollination service to fields along the landscape gradient. Projected pollination services declined as the area occupied by natural vegetation decreased. We identified thresholds at which bee pollination no longer supported maximum seed set, which were landscapes with approximately one quarter (27 %) of nearby natural vegetation for brinjal fields and one fifth (18 %) for mustard. Our findings indicate that preserving or restoring the cover of natural habitats above these minimum thresholds could be a valuable strategy for maintaining pollinator abundance and safeguarding yield in these bee-pollinated crops.Darwin Initiativ

Breeding system and spatial isolation from congeners strongly constrain seed set in an insect-pollinated apomictic tree: Sorbus subcuneata (Rosaceae)

The article associated with this dataset is in ORE at: http://hdl.handle.net/10871/26965The datasets are the results of 1) pollen grain accumulation on stigmas. 2) Flowering phenology of individual trees as % of opened buds, with 50 percentile values of the cumulative flowering curve. 3) Location data for all trees of both species of flowering size (see article text) plus connectivity measures of maternal seed trees to all S. admonitor trees. X and y coordinates are GB OS National Grid. This data is related to the Scientific Reports paper of the same title.Whitley Wildlife Conservation Trust, Paignton Zoo Environmental ParkNER

Psychopolitics: Peter Sedgwick’s legacy for mental health movements

This paper re-considers the relevance of Peter Sedgwick's Psychopolitics (1982) for a politics of mental health. Psychopolitics offered an indictment of ‘anti-psychiatry’ the failure of which, Sedgwick argued, lay in its deconstruction of the category of ‘mental illness’, a gesture that resulted in a politics of nihilism. ‘The radical who is only a radical nihilist’, Sedgwick observed, ‘is for all practical purposes the most adamant of conservatives’. Sedgwick argued, rather, that the concept of ‘mental illness’ could be a truly critical concept if it was deployed ‘to make demands upon the health service facilities of the society in which we live’. The paper contextualizes Psychopolitics within the ‘crisis tendencies’ of its time, surveying the shifting welfare landscape of the subsequent 25 years alongside Sedgwick's continuing relevance. It considers the dilemma that the discourse of ‘mental illness’ – Sedgwick's critical concept – has fallen out of favour with radical mental health movements yet remains paradigmatic within psychiatry itself. Finally, the paper endorses a contemporary perspective that, while necessarily updating Psychopolitics, remains nonetheless ‘Sedgwickian’

Structured oligo(aniline) nanofilms via ionic self-assembly

Conducting polymers have shown great potential for application in electronic devices. A major challenge in such applications is to control the supramolecular structures these materials form to optimise the functionality. In this work we probe the structure of oligo(aniline) thin films (of sub-μm thickness) drop cast on a silicon substrate using synchrotron surface diffraction. Self-assembly was induced through doping with an acid surfactant, bis(ethyl hexyl) phosphate (BEHP), resulting in the formation of well-ordered lamellae with the d-spacing ranging from 2.15 nm to 2.35 nm. The exact structural characteristics depended both on the oligomer chain length and film thickness, as well as the doping ratio. Complementary UV/Vis spectroscopy measurements confirm that such thin films retain their bulk electronic properties. Our results point to a simple and effective ionic self-assembly approach to prepare thin films with well-defined structures by tailoring parameters such as the oligomer molecular architecture, the nanofilm composition and the interfacial roughness

Effects of the neonicotinoid pesticide thiamethoxam at field-realistic levels on microcolonies of Bombus terrestris worker bumble bees

Copyright © 2013 Elsevier. Notice: this is the author’s version of a work that was accepted for publication in Ecotoxicology and Environmental Safety. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Ecotoxicology and Environmental Safety, 2014, Vol. 100, pp. 153-158 at: http://dx.doi.org/10.1016/j.ecoenv.2013.10.027Neonicotinoid pesticides are currently implicated in the decline of wild bee populations. Bumble bees, Bombus spp., are important wild pollinators that are detrimentally affected by ingestion of neonicotinoid residues. To date, imidacloprid has been the major focus of study into the effects of neonicotinoids on bumble bee health, but wild populations are increasingly exposed to alternative neonicotinoids such as thiamethoxam. To investigate whether environmentally realistic levels of thiamethoxam affect bumble bee performance over a realistic exposure period, we exposed queenless microcolonies of Bombus terrestris L. workers to a wide range of dosages up to 98 μg kg−1 in dietary syrup for 17 days. Results showed that bumble bee workers survived fewer days when presented with syrup dosed at 98 μg thiamethoxam kg−1, while production of brood (eggs and larvae) and consumption of syrup and pollen in microcolonies were significantly reduced by thiamethoxam only at the two highest concentrations (39, 98 μg kg−1). In contrast, we found no detectable effect of thiamethoxam at levels typically found in the nectars of treated crops (between 1 and 11 μg kg−1). By comparison with published data, we demonstrate that during an exposure to field-realistic concentrations lasting approximately two weeks, brood production in worker bumble bees is more sensitive to imidacloprid than thiamethoxam. We speculate that differential sensitivity arises because imidacloprid produces a stronger repression of feeding in bumble bees than thiamethoxam, which imposes a greater nutrient limitation on production of brood.Natural Environment Research Council (NERC

Modelling the capture, by pine cones, of wind-dispersed pollen

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.In this study, computational fluid dynamics (CFD) was used to simulate the dominant influences of conelet aerodynamics. To this end, airflow and particle trajectories around a virtual conelet have been visualized at a very high resolution to reveal the mechanisms of the conelet-pollen interaction. Furthermore, surfaces of the conelet have been selected to 'absorb' particles so that pollen capture could be exactly quantified. Therefore three-dimensional imaging has been introduced to obtain accurate representations of conelet morphology for aerodynamic analysis of wind pollination using CFD. The results of spore captures will be compared to results obtained for a facsimile (/figure 1/) in wind tunnel experiments. Possible influence factors for pollen capture are scale camber or orientation. Series of conelets are planned to be produced, each series varying experimentally in a single feature (or more if interactions are evident). A feature is demonstrated to be a major influence if its variation is systematically associated with the aerodynamic performance of conelets.vk201