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991.
Mineral deposits in the Cupp‐Coutunn/Promeszutochnaya cave system (Turkmenia, central Asia) record a phase of hydrothermal activity within a pre‐existing karstic groundwater conduit system. Hydrothermal fluids entered the caves through fault zones and deposited sulphate, sulphide and carbonate minerals under phreatic conditions. Locally, intense alteration of limestone wall rocks also occurred at this stage. Elsewhere in the region, similar faults contain economic quantities of galena and elemental sulphur mineralization. Comparisons between the Pb and S isotope compositions of minerals found in cave and ore deposits confirm the link between economic mineralization and hydrothermal activity at Cupp‐Coutunn. The predominance of sulphate mineralization in Cupp‐Coutunn implies that the fluids were more oxidized in the higher permeability zone associated with the karst aquifer. A slight increase in the δ34S of sulphate minerals and a corresponding δ34S decrease in sulphides suggest that partial isotopic equilibration occurred during oxidation. Carbonate minerals indicate that the hydrothermal fluid was enriched in 18O (δ18OSMOW ~ + 10‰) relative to meteoric groundwater and seawater. Estimated values for δ13CDIC (δ13CPDB ~ ? 13‰) are consistent with compositions expected for dissolved inorganic carbon (DIC) derived from the products of thermal decomposition of organic matter and dissolution of marine carbonate. Values derived for δ13CDIC and δ18Owater indicate that the hydrothermal fluid was of basinal brine origin, generated by extensive water–rock interaction. Following the hydrothermal phase, speleothemic minerals were precipitated under vadose conditions. Speleothemic sulphates show a bimodal sulphur isotope distribution. One group has compositions similar to the hydrothermal sulphates, whilst the second group is characterized by higher δ34S values. This latter group may either record the effects of microbial sulphate reduction, or reflect the introduction of sulphate‐rich groundwater generated by the dissolution of overlying evaporites. Oxygen isotope compositions show that calcite speleothems were precipitated from nonthermal groundwater of meteoric origin. Carbonate speleothems are relatively enriched in 13C compared to most cave deposits, but can be explained by normal speleothem‐forming processes under thin, arid‐zone soils dominated by C4 vegetation. However, the presence of sulphate speleothems, with isotopic compositions indicative of the oxidation of hydrothermal sulphide, implies that CO2 derived by reaction of limestone with sulphuric acid (‘condensation corrosion’) contributed to the formation of 13C‐enriched speleothem deposits.  相似文献   
992.
This article presents a brief survey and analysis of the most intimate coupling of culture and national projects that occurred in Central Europe following the success of the Italian and German nation‐states established in this manner during the third quarter of the nineteenth century. Language is the very ‘stuff’ of culture as well as the instrument of communicating and reaffirming cultural difference vis‐à‐vis other cultures. As such, language became central to the processes of nation‐ and nation‐state‐building in Central Europe, leading to politicisation of language and also of linguistics and philology, which were expected to fortify the nations and their nation‐states than rather to lend themselves to objective research. It is proposed that this specific Central European interweaving of language and national projects may be better comprehended through the application of Einar Haugen's model of language standardisation and Miroslav Hroch's model of nation‐building. These two models in the Central European case seem to be closely corresponding to each other. The short catalogue of language elements used to produce national differentiation closes this contribution.  相似文献   
993.
The Illawarra Region some 80 kilometres south of Sydney is characterised by a prominent coastal escarpment that rises to 700 m within 12 km of the coast and forms a locus for frequent, high intensity rainfall events. One of the most recent recorded events occurred on 17 August 1998 with rainfall intensities at several pluviometers exceeding 120 mm hr‐1 over a duration of one hour, with up to 249 mm falling in 3.5 hours during the main storm burst. Detailed pluviometer data indicate that the storm was non‐stationary and moved down catchment producing a widespread zone of 120 mm hr‐1 intensity rainfall over a 30 minute duration across mid‐lower catchment areas after similar intensity but longer duration rainfall in catchment headwaters. Slope‐area reconstructions of peak discharge indicate that small catchments on the escarpment within the zone of maximum intensity experienced close to 100% rainfall‐runoff relationships, with peak discharges correlated to short duration (<1 hr) peak rainfall intensities. Widespread erosion occurred particularly where urban development had encroached on natural water courses. Debris/hyperconcentrated flows originating from both anthropogenic and natural sediment sources caused damage to urban areas. This paper provides an overview of the spatial and temporal characteristics of the 17 August 1998 storm, the hydrologic and geomorphic response of the streams, and the nature of damage to urban areas. It reassesses the frequency of recent high‐magnitude rainfall/flood events in the region, discussing the relationships between rainfall intensities, estimates of flood magnitudes and stormwater channel capacities.  相似文献   
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This study evaluates a method for obtaining stature estimates for populations represented by skeletal material, with individuals buried in a supine position. During the excavation of a Danish mediaeval cemetery, in situ skeletal length in the grave was measured from a point above the cranial point farthest from the body to the most distal point of the talus. The measurement was made with a folding rule placed on the sagittal midline of the skeleton, allowed to follow any curvature of the skeleton in situ. In the laboratory, stature was reconstructed anatomically, and this stature was regarded as an accurate estimate of living stature. Stature was also reconstructed from femur length by two linear regression procedures: 1) by sample and sex specific formulae, employing a leave‐one‐out approach, and 2) by sex wise formulae for Euro‐Americans from Trotter & Gleser (1952, American Journal of Physical Anthropology 10 : 463–514). Skeletal length in the grave and the two stature estimates based on linear regression were compared to anatomically reconstructed stature. Skeletal length in the grave estimated anatomically reconstructed stature with practically no bias (95% CI: −1.3–1.5 cm). Sample specific regression formulae estimated anatomically reconstructed stature also with no bias (95% CI: −1.2–1.1 cm). In contrast, statures calculated from Trotter & Gleser's regression formulae estimated anatomically reconstructed stature with a bias of about 4 cm (95% CI: 3.3–5.0 cm). Estimates of stature variance were biased for all three estimation procedures. However, for samples of adults, an adjusted variance estimate can be obtained by subtracting 8.7 cm2 from the variance obtained from skeletal lengths in the grave. It is recommended to measure skeletal length in the grave whenever possible, and use this measurement for estimating statures for prehistoric and early historic populations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
996.
Portable gamma ray spectrometry (PGRS) provides a non destructive means to analyst quantitatively large artefacts, such as building stones, for the radioelements K. U and Th. Nine Raman granitoid columns at the Leptis Magna Ruins in Windsor Great Park, London, were measured in situ by PGRS. Corrections for the environmental background contribution to the gamma ray flux measured, and for the shape and size of the columns, are described Comparison of the PGRS data with a radioelement data base for Roman granite sources indicates that most of the columns originated in the Troad area of Turkey. Two columns could not be unambiguously provenanced using PGRS alone because there is insufficient difference between radioelement concentrations in certain sources. However, non‐destructive measurements of magnetic susceptibility, used in conjunction with PGRS data, suggest that these two columns originated in the Kozak Daǧ, also in Turkey.  相似文献   
997.
Location Determinants of New Foreign-Owned Manufacturing Plants   总被引:5,自引:0,他引:5  
In this paper we examine the county-level pattern of new foreign-owned manufacturing plants in the United States from 1989 through 1994. We construct a model to produce insights into the differences in the location of these plants among Bureau of Economic Analysis regions, as well as between rural and urban counties. Higher levels of economic size, educational attainment, the existing manufacturing base, and transportation infrastructure are found to be associated with larger numbers of new foreign-owned plants. Meanwhile, higher levels of taxes and labor-intensiveness are found to be associated with smaller numbers of new plants. Comparing regions, we find that the main advantages of the Southeast region stem from a relatively high manufacturing base and relatively low taxes. Comparing urban with rural counties, we find that urban counties possess more favorable average values for nearly all the explanatory variables.  相似文献   
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