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31.
The OSL, post-IR OSL and pulsed post-IR OSL applied to polymineral grains and calculated by fitting to the data the contributions from fast, medium and slow components revealed that the polymineral samples under study are dominated by the medium component. An increase in D e ’s with increasing integration intervals was observed, which is considered as an indication of increasing medium and decayed fast component; and the equivalent doses obtained using different components or minerals reflect also the shape of the dose distributions. The identified fast component in polymineral sample has photoionization cross section of 1.2±0.02 × 10?17 cm2. The present study shows the usefulness of the application of different luminescence techniques combined with fitting procedures as a check which should be adopted in dating protocols. Based on luminescence ages obtained on poly-mineral grains from prehistoric pottery samples from the Boroo settlement, Mongolia, which are in agreement with independent age control by 14C on charcoal material, it is argued that the manufacturing of Xiongnu — pottery at this site lasted until ca. 130±75 AD.  相似文献   
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Albania is a possible stepping-stone for the dispersal of Homo sapiens into Europe, since Palaeolithic traces (namely from the so-called Uluzzian culture) have been discovered in neighboring Greece and Italy. After two years of searching for evidence of modern humans in Albania we here report on excavated test trenches representing two time slices: an Aurignacian open-air site from southern Albania and two Epigravettian cave sites in central and northern Albania—areas heretofore archaeologically unknown. The new Albanian data fill a gap in the eastern Adriatic archaeological record for Marine Isotope Stages 3 and 2. Adding current knowledge of Late Pleistocene landscape evolution, a “contextual area model” can be constructed describing the habitats of these human populations.  相似文献   
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This contribution analyses the role of corporate regional responsibility (CRR) in cluster development, using the case of Volkswagen and its headquarter city Wolfsburg for illustration. The conceptual discussion of CRR and cluster development shows obvious synergies, as both the firm and the region benefit from the firm-led upgrading of the business environment. Recognising that their fate is mutually linked, Volkswagen started making strategic investment in its headquarter location in the late 1990s, based on a cluster concept. Despite apparent achievements in attracting suppliers and increasing the attractiveness and dynamism of the location, the company town’s dependence on its dominant firm remains obvious. Wolfsburg thus provides a showcase for the congruence of interests between firm and city as a precondition for successful CRR, but its transferability appears confined to company towns dominated by a single employer.  相似文献   
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The Ruhr area has advanced to the largest university region in Germany – often unnoticed within and outside. At the same time scientific institutions have become a major economic factor. Because of the higher and extra-university research institutions about 2.5 billion euros are effective as a demand potential in the region. 1.7 billion euros of this amount are directly associated with investments and operating expenditures of the scientific institutions as well as consumptions of employees and students. Additional 770 million euros result in revenues of many branches such as trade, housing, gastronomy sector, handcraft industry etc. It should not be underestimated that higher and extra-university research institutions generate with their research activities particular funding from the European Union or the rest of Germany for benefit of the region. Each euro spent by the state government for basic funding creates 39 cents third-party funding. These regional-economic effects result in noticeable employment impacts within the region. Around 25,000 people are directly employed in higher and extra-university research institutes or student unions (Studierendenwerke), about 22,000 jobs in other economic sectors are ensured or created by the induced demand. Science has thus become an important economic factor and represents an essential counterbalance to employment decline in shrinking industries of the region. The specific inclusion of science in a regional development strategy and targeted relining with appropriate measures to strengthen the science creates therefore an effective starting point for the design of structural change.  相似文献   
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This paper explores the impact of industrial clusters on regional growth at the German labour market region level using a regional convergence model. Based on the results of an exploratory study of the geography of German industrial clusters, we are able to differentiate the impact of industrial clustering from a horizontal and a vertical perspective while taking regional convergence into consideration. The results indicate that in addition to an all-German process of convergence, a specific East German one can be identified. The different types of industrial clusters show mixed effects within this framework. While vertically isolated industrial clusters have a negative impact on regional growth in this period, positive growth effects can be identified when industrial clusters show an intra-regional vertical interconnectedness.  相似文献   
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The newly developed lexsyg system by Freiberg Instruments is a versatile luminescence reader, suited for research on the luminescence of materials, fundamental research in luminescence dating, but also for routine mass measurements in retrospective dosimetry as well as in dating application. The 80 sample storage wheel is disconnected from the measurement chamber and therefore crosstalk of optical stimulation is absent and cross-irradiation is negligible from the α- and β-sources, which are providing very uniform irradiations, with the latter especially designed for radiofluores-cence (RF) measurement. Optical excitation sources and filter wheels to vary detection wavelengths can be programmed to change at almost any time within measurement sequences, including the auto-mated change of an optional wheel holding up to four different detectors. Thermoluminescence meas-urements and preheating are possible with a versatile heater, which can be programmed for linear or non-linear heating or cooling, as well as holding a temperature constant. Rates as well as durations can be varied, together with individual ramping, staging and cooling for an almost unlimited number of steps. Violet- and IR-lasers, green and blue LED-arrays can be operated in continuous (CW) or modulated mode (linear/non-linear), and optionally for pulsed as well as time resolved luminescence detection. Six arrays of power LEDs allow the simulation of different bleaching regimes (‘solar simu-lator’), while luminescence detection can be achieved by a variety of photomultiplier tubes and by CCD cameras for spatially resolved measurements and luminescence spectra.  相似文献   
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The story of the Navajo Nation and uranium mining is, at itsheart, a tale of environmental justice. From the late 1940suntil the 1960s, uranium mining by private corporations whosesole purchaser was the federal government, employed Navajosto work the mines in the Four Corners area. When the uraniumboom ended, the miners and their families were left with hugepiles of uranium tailings, compromised health, and a scarredlandscape. The Navajo People and Uranium Mining fills a crucialchapter of this story in a short, yet powerful work that illuminatesthe ongoing social, psychological, and environmental problemsrelated  相似文献   
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The Loch of Clickimin, Shetland, is well known for its broch and associated monuments supposedly of the Bronze and Iron Ages, although the former date is disputed. Pollen, diatom and sedimentological investigations permit fresh insights into the landscape and economic impacts of those who constructed the monuments, reveal that the environs of the site experienced environmental change from Neolithic times onward and provide the first Holocene radiocarbon dates from the immediate locality. The broch-building period witnessed a continuation of pre-existing pastoral husbandry for which heather burning may have exacerbated the natural spread of blanket peat. Initially, no evidence was adduced for local arable activity in the present investigation, and this was thought to be consistent possibly with the low numbers of excavated querns and the absence of cereal macrofossil finds when compared with other Shetland broch sites. The application of ‘rapid scanning’ techniques, however, led to the discovery of a consistent cereal-type pollen representation from Bronze Age times onwards. The discrepancies between the palaeoenvironmental evidence and the environmental and palaeoeconomic inferences made by the excavator of the site are explored. Evidence is presented that both supports and contradicts previous assumptions surrounding an important archaeological site.  相似文献   
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