5,398 research outputs found
A geochemical drainage survey of the Fleet granitic complex and its environs
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
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
A spatial analysis of physiological changes associated with infection of cotyledons of marrow plants with cucumber mosaic virus
Changes in host primary metabolism associated with the compatible interaction between cucumber mosaic virus and cotyledons of the marrow plant (Cucurbita pepo L.) have been localized, first by measuring activities of key enzymes in infected and uninfected regions of the cotyledon, and second by histochemical techniques applied to tissue prints of the infected region. A series of progressive metabolic changes occurs within the expanding infected lesion. Virus replication and the synthesis of viral protein at the periphery creates a strong sink demand associated with increased activities of anaplerotic enzymes, increased photosynthesis, and starch accumulation. Inside the lesion, when the synthesis of virus has declined, photosynthesis is reduced, starch is mobilized, and the emphasis of metabolism is shifted toward glycolysis and mitochondrial respiration. These changes are associated spatially with the onset of chlorosis. A decrease in total protein synthesis in this inner zone could be instrumental in some or all of these changes, leading to symptoms of viral infection
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Reflectance spectra of Mesosiderites: Implications for asteroid 4 Vesta
Oxygen isotopic data argues that HEDs and mesosiderites may be from the same parent body. A spectral survey of mesosiderites was done to determine their spectral properties in the visible and near-infrared and compare to HEDs
Testing Assumptions in Deliberative Democratic Design: A Preliminary Assessment of the Efficacy of the Participedia Data Archive as an Analytic Tool
At smaller social scales, deliberative democratic theory can be restated as an input-process-output model. We advance such a model to formulate hypotheses about how the context and design of a civic engagement process shape the deliberation that takes place therein, as well as the impact of the deliberation on participants and subsequent policymaking. To test those claims, we extract and code case studies from Participedia.net, a research platform that has adopted a self-directed crowd-sourcing strategy to collect data on participatory institutions and deliberative interventions around the world. We explain and confront the challenges faced in coding and analyzing the Participedia cases, which involves managing reliability issues and missing data. In spite of those difficulties, regression analysis of the coded cases shows compelling results, which provide considerable support for our general theoretical model. We conclude with reflections on the implications of our findings for deliberative theory, the design of democratic innovations, and the utility of Participedia as a data archive
Gradient refractive index of the crystalline lens of the Black Oreo Dory (Allocyttus Niger): comparison of magnetic resonance imaging (MRI) and laser ray-trace methods
AbstractThe gradient refractive index of the crystalline lens in the Black Oreo Dory (Allocyttus Niger) was determined using two methods; an optimisation program based on finite ray-tracing and the path of laser beams through the lens, and magnetic resonance imaging (MRI) and the linear relationship between refractive index and nuclear transverse relaxation rates. The methods showed good agreement in the cortical zone of the lens, but the lack of free water in the core of the lens made MRI measurement impossible in this region. The laser-optimisation method gave mean values of 1.368 and 1.543 for the surface and core refractive indices respectively, with a radial distribution for the gradient refractive index given by n(r)=1.543−0.121r2−0.033r4−0.021r6
Prediction of low-frequency vibration transmission through an automotive door mount system using the finite element method
Published ArticleThe phenomenon of automotive door panel vibration is complex, because it comprises the simultaneous interaction of many competing factors. Numerical simulation of such behaviour is not simplistic and is challenging at both the scientific and technical levels. Anecdotal evidence suggests that, until now, the characterisation of door panel vibration in terms of its door mount system has not yet been contemplated. This paper describes a numerical model and its application to a case study to investigate the vibrational behaviour of a door panel in terms of its door mount system. Results of the numerical model are compared with those obtained from physical measurements and are found to be satisfactory
Intravenous immunoglobulin in acute Sydenham's chorea: A systematic review.
Abstract
Sydenham's chorea (SC) is a major manifestation seen in 25% of patients with acute rheumatic fever. SC is the prototypic autoimmune neurological disorder, which has a less appreciated associated risk of psychiatric morbidity. We undertook a systematic review to examine whether the use of intravenous immunoglobulin affects clinical recovery and morbidity
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