4,814 research outputs found

    The role of the North Atlantic Oscillation in controlling U.K. butterfly population size and phenology

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    Copyright @ 2012 The Authors. This article can be accessed from the links below.This article has been made available through the Brunel Open Access Publishing Fund.1. The North Atlantic Oscillation (NAO) exerts considerable control on U.K. weather. This study investigates the impact of the NAO on butterfly abundance and phenology using 34 years of data from the U.K. Butterfly Monitoring Scheme (UKBMS). 2. The study uses a multi-species indicator to show that the NAO does not affect overall U.K. butterfly population size. However, the abundance of bivoltine butterfly species, which have longer flight seasons, were found to be more likely to respond positively to the NAO compared with univoltine species, which show little or a negative response. 3. A positive winter NAO index is associated with warmer weather and earlier flight dates for Anthocharis cardamines (Lepidoptera: Pieridae), Melanargia galathea (Lepidoptera: Nymphalidae), Aphantopus hyperantus (Lepidoptera: Nymphalidae), Pyronia tithonus (Lepidoptera: Nymphalidae), Lasiommata megera (Lepidoptera: Nymphalidae) and Polyommatus icarus (Lepidoptera: Lycaenidae). In bivoltine species, the NAO affects the phenology of the first generation, the timing of which indirectly controls the timing of the second generation. 4. The NAO influences the timing of U.K. butterfly flight seasons more strongly than it influences population size.This study was supported by a multi-agency consortium led by the U.K. Department for Environment, Food and Rural Affairs (Defra), including the Countryside Council for Wales, the Joint Nature Conservation Committee, the Forestry Commission, Natural England, the Natural Environment Research Council, the Northern Ireland Environment Agency and Scottish Natural Heritage. This article is made available through the Brunel Open Access Publishing Fund

    A geochemical drainage survey of the Fleet granitic complex and its environs

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    A regional geochemical drainage reconnaissance programme was undertaken over 900 km2 of south-west Scotland centred on the Fleet granitic complex. Rocks of Ordovician and Silurian age outcrop over the area, into which have been intruded the Fleet and Loch Doon plutons. Multi-element analysis of stream sediments and heavy mineral concentrates shows a number of patterns of trace element distribution related to different lithologies and to mineralisation. Broad scale patterns exhibited by some elements denote compositional variations within the Lower Palaeozoic sediments and within the Fleet and Loch Doon plutons. On thebasis of the drainage data the sedimentary rocks have been divided into eight distinct geochemical units each characterised by different element distribution patterns. The Fleet and Loch Doon plutons have been sub-divided on the same basis. Follow-up investigations of drainage anomalies led to the discovery of both structure-controlled and disseminated base metal mineralisation in the Penkiln drainage basin within the salthernaureole of the Loch Doon granite. The distribution of Cu, F’b and Zn to the south and south-west of the Fleet granite suggests a zonation of vein minerahsation, with Cu prominent adjacent to the granite contact and F’b and Zn having a wider dispersion away from the granite. Other anomalies delineate a mineralised lineament that follows the regional strike of the Lower Palaeozoic sediments, southeast of the Fleet granite

    A reconnaissance geochemical drainage survey of the Criffel-Dalbeattie granodiorite complex and its environs

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    Regional geochemical reconnaissance by stream sediments and panned concentrates was undertaken over an area of 850 km 2 of south-west Scotland. Rocks of Ordovician to Permian age are exposed within the area but the major part is occupied by the Criffel-Dalbeattie granodiorite complex. Multi-element analysis of the samples collected demonstrates patterns of trace element distribution related to the geology and Broad-scale patterns in the distribution of some elements reflect compositional anumber of mineralisation. variations in both the Lower Palaeozoic turbidite sequence and the Criffel- Dalbeattie granodiorite complex, both of which may be sub-divided into specific units on the basis of the geochemical data. The follow-up of copper anomalies in drainage samples from the Black Stockarton Moor area led to the discovery of porphyry-style copper mineralisation within an arcuate belt at least 5 km by 1 km within the Black Stockarton Moor subvolcanic complex and of related disseminated copper mineralisation at Screel Burn. The area to the west of the Criffel-Dalbeattie plutonic complex is also characterised by relatively high boron levels in stream sediments reflecting the widespread occurrence of tourmaline both in association with and peripheral to the copper mineralisation. Vein mineralisation, usually containing baryte in addition to base.metals, is also identifiable from the drainage survey at the eastern margin of the Criffel-Dalbeattie granodiorite; in association with the Lower Carboniferous rocks along the Solway coast; and within the Lower Palaeozoic turbidites in the west of the area

    MEASUREMENT OF AVERAGE NEUTRON ENERGIES FOR (alphaalpha,n) NEUTRON SOURCES

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    A method is presented for measuring the average energy of the neutrons from a source. The attenuation of the neutrons by polyethylene is measured by the use of a long counter in good geometry. The attenuation length is a sensitive function of the neutron energy. The average neutron energies from several ( alpha ,n) sources were measwed and agree well with values obtained by other techniques. (auth

    Pro Con debates in clinical medicine Infection prevention and control in cystic fibrosis: one size fits all? The argument against

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    As awareness of the risks of cross infection has increased, infection prevention and control measures have become more draconian. Infection control measures can have a profound effect of the organisation and delivery of CF services and on the lives of people with CF outside the hospital. However, the consequences of inadequate infection control measures may be the permanent acquisition of a chronic infection which is virtually untreatable. Recommendations for infection prevention and control therefore must protect patients but should also be evidence-based and proportionate. This article will review the literature, juxtaposing evidence and popular practice

    ‘Conflict versus Congruence’: A qualitative study exploring the experience of gender dysphoria for adults with autism spectrum disorder

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    An emergent evidence base indicates a higher prevalence of autism exists amongst people attending gender identity clinics. This qualitative study explored adults’ with autism experiences of coming to understand and address their gender dysphoria (GD). Data were collected and analysed using Grounded Theory. Ten adults with autism and GD undertook semi-structured interviews. A tentative theoretical framework of common processes involved in understanding and addressing GD for individuals with autism was developed. The experience is captured in the core category—Conflict versus Congruence. A key finding was the impact of autism as a barrier but sometimes a protective factor in participants’ understanding and addressing GD. Participants appeared to achieve greater personal congruence and wellbeing upon transition. Nevertheless, conflicts remained as they navigated the social world with a continuing fear of hostility and sense of difference due to having two stigmatised identities

    Current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization

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    The balances of particles and charges in the volume of parallel-plane ionization chamber are considered. Differential equations describing the distribution of current densities in the chamber volume are obtained. As a result of the differential equations solution an analytical form of the current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization in the volume is got.Comment: 8 pages, 4 figure

    Tree species identity influences the vertical distribution of labile and recalcitrant carbon in a temperate deciduous forest soil

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    In terrestrial environments, soil organic matter (SOM) is the largest organic carbon (C) pool. The quantity and quality of organic carbon in soils can be affected by vegetation through influencing the inputs and outputs of SOM. We examined how storage and quality of C in SOM were affected by vegetation under grass cover or single and a polyculture plot of Betula pendula, Alnus glutinosa and Fagus sylvatica. An acid hydrolysis approach was used to quantify three SOM fractions differing in biodegradability. Tree species identity and stand composition had no significant effect on the total amount of C stored in different SOM fractions to a depth of one meter. However, when examining individual SOM fractions in the upper layers of the soil profile, significantly more C was stored in the putatively more labile fractions 1 and 2 under F. sylvatica and A. glutinosa, respectively. In deeper soil layers, the highest storage of recalcitrant organic C was found under the tree polyculture. The vertical distribution of these three soil organic C pools was compared to C inputs via decomposed leaf litter. Our data indicated that in the tree species polyculture, combining litter inputs of multiple species can have a positive impact on the accumulation of acid resistant recalcitrant C in deep soil layers in 4 years. This C fraction has the greatest potential for long-term sequestratio
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