14,767 research outputs found

    The impacts for stone curlews of increased traffic on the A11. Model and predictions

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    Stone curlew nest density in the Breckland region of Eastern England was shown to be negatively related to ‘nearby’ housing density and ‘nearby’ trunk road traffic (based on new traffic data for the period 1988-2006). However, no statistically significant additional relationship with non-trunk A-road traffic could be detected. We recommend using the statistical modelling predictions in the report Table 5 as the best currently available estimates of the potential effect of a 70% increase in A11 average daily (March-August)two-way traffic above the average All traffic levels in 2002-06. The predicted effect of a 70% increase in A11 traffic is for a reduction from current observed nest numbers on suitable arable land of 3.7% with no changes in housing density or 4.9% when combined with the predicted effect of housing options. A reduction of 7.3% is predicted for semi-natural grassland and SSSI habitats. Taking both semi-natural grassland/SSSI and arable habitats together, the observed total average nest numbers for the period 2002-2006 was 221.4, and the prediction following a 70% increase in traffic on the A11 is 210.8, a reduction of 10.6 nests (4.8%)

    Study of storm time fluxes of heavy ions

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    Ion composition data sets from Lockheed instruments on a variety of spacecraft were used in combination with each other and with data from other instruments to address a variety of problems regarding plasma sources, energization and transport within the magnetosphere. The availability of data from several differing orbits has given a highly flexible approach to attacking the continually evolving questions of magnetospheric physics. This approach is very successful and should be continued in the future

    Development of a polysilicon process based on chemical vapor deposition, phase 1

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    The development of a dichlorosilane-based reductive chemical vapor deposition process for the production of polycrystalline silicon is discussed. Experimental data indicate that the ease of ignition and explosion severity of dichlorosilane (DCS)/air mixtures is substantially attenuated if the DCS is diluted with hydrogen. Redesign of the process development unit to accommodate safety related information is described. Several different sources of trichlorosilane were used to generate a mixture of redistributed chlorosilanes via Dowex ion exchange resin. The unseparated mixtures were then fed to an experimental reactor in which silicon was deposited and the deposited silicon analyzed for electrically active impurities. At least one trichlorosilane source provided material of requisite purity. Silicon grown in the experimental reactor was converted to single crystal material and solar cells fabricated and tested

    Metamorphic Conditions of an Archean Core Complex in the Northern Wind River Range, Wyoming

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    The Archean granulite-facies rocks of the northern Wind River Range consist of extensive granitic orthogneisses and migmatites hosting banded iron formations, amphibolites, metapelites, metabasites, ultramafites and quartzites. Quantitative pressure and temperature estimates from inclusions within garnet porphyroblasts are 815±5O%C and 8±1 kb using equilibria buffered by the assemblages spinel-quartz-garnet-sillimanite and garnet-rutile-ilmenite-sillimanite-quartz. Pressure-temperature estimates from the groundmass core assemblages of the banded iron formations and hornblende granulites are 750 ±50 %C and 5·5 ± 1 kb using garnet-clinopyroxene, garnet-orthopyroxene, and two-pyroxene thermometry, and geobarometers based on the assemblages garnet-quartz-plagioclase-orthopyroxene and orthopyroxene-olivine-quartz. Rim compositions of the matrix minerals indicate nearly isobaric cooling from the conditions of 750 %C and 5-5 kb to < 600%C at 5 kb. Taken together, the P-T estimates from both the garnet inclusions and matrix assemblages are consistent with a clockwise P-T-t path for this terrane. Temperature estimates based on oxygen isotope thermometry in the banded iron formations vary systematically with the degree of visible late-stage deformation. There is no correlation between the isotopic temperature estimates and those from cation-based thermometers. The highest pressures and temperatures for the Wind River terrane are preserved by the inclusions in garnet porphyroblasts. The ability of these inclusions to preserve chemistries corresponding to higher pressures and temperatures is attributed to the combined effects of inclusion isolation and fixed inclusion volume within the garnet porphyroblasts. Cation-based thermometers in the groundmass preserve lower temperatures as a result of diffusional partial resetting. Isotopic thermometry will yield the lowest temperatures if there is even minor retrograde deformation. Geothermobarometry for the northern Wind River Archean terrane is consistent with a tectonic regime of doubly thickened crust. Peak metamorphic conditions preserved in the cores of the garnets are compatible with deep burial during the early stages of tectonism. Rapid to intermediate uplift due to erosion of the upper plate could explain the nearly isothermal decompression from 8·0 to 5-5 kb. The later, nearly isobaric, cooling path indicated by the rim compositions of the matrix minerals is consistent with relaxation of the elevated geother

    Unsung heroes: who supports social work students on placement?

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    Since the introduction of the three year degree programme in 2003, social work education has undergone a number of significant changes. The time students spend on placement has been increased to two hundred days, and the range of placement opportunities and the way in which these placements have been configured has significantly diversified. A consistent feature over the years, however, has been the presence of a Practice Educator (PE) who has guided, assessed and taught the student whilst on placement. Unsurprisingly, the role of the PE and the pivotal relationship they have with the student has been explored in the past and features in social work literature. This paper, however, concentrates on a range of other relationships which are of significance in providing support to students on placement. In particular it draws on research to discuss the role of the university contact tutor, the place of the wider team in which the student is sited, and the support offered by family, friends and others. Placements and the work undertaken by PE’s will continue to be integral to the delivery of social work education. It is, however, essential to recognise and value the often over looked role of others in providing support to students on placement
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