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81.
ABSTRACT We use disaggregated data on Chilean plants, and the Chilean input–output table to examine the impact of agglomeration spillovers on total factor productivity (TFP). In common with previous studies, we find evidence for intraindustry spillovers, but none for general cross‐industry spillovers. This picture changes when we take vertical industry relations into account. There are important productivity spillovers from plants in upstream industries. Interestingly, a similar effect cannot be found from plants in downstream industries. The number of plants in these sectors has no effect on plant‐level TFP, just as the number of plants in other industries that are neither important upstream suppliers nor downstream customers also has no effect. 相似文献
82.
The influence of relief, as well as other environmental features such as soils or the hydrological regime, on prehistoric settlement patterns is commonly accepted. Settlement patterns and preferences changed over time in different areas, so it is difficult to formulate general rules of human behaviour throughout history. In lowland areas of the temperate zone, which lack radical relief changes and have widespread access to water resources, specific settlement preferences and significant changes in these preferences are difficult to interpret.New methods developed to address the problem of the settlement transformations as a result of prehistoric settlement and economic processes using multivariate statistics have been adapted for the middle part of the Great Poland Lowland. In this region, data from the Polish Archaeological Record Project database have been used.Models of the dependence between geomorphological features and settlement intensity form the basis for estimating changes in prehistoric settlements. The degree of preference (or avoidance) is a nonparametric function of the number of archaeological sites observed in the area relative to the number of sites expected from a completely random pattern. The most crucial factors for settlement are distance to plateau edges, distance to water bodies, and the wetness index. The results show that the entire investigated area is more or less suitable for settlement, but the most occupied terrains are the areas near plateau edges. 相似文献
83.
Gearóid Ó Tuathail 《Political Geography》2009,28(1):4-15
The aftermaths of terrorist spectacles are intensely consequential moments in the making of geopolitical meaning. This paper develops a critical geopolitical account of the ways in which key actors involved in the terrorist incident at School Number 1 in Beslan North Ossetia constructed its meaning and justified their actions. The event is examined from three perspectives: the terrorist's Beslan, the Kremlin's Beslan and the contested meaning of Beslan among Ossetians and others in the North Caucasus. Multiple sources are utilized in the construction of the account: an English language archive of Russian reporting on the event, accounts of the siege, statements by key protagonists, elite interviews in North Ossetia, and the results of a survey question in North Ossetia and the North Caucasus on Beslan. The paper examines the construction of blame by the various actors and relates it to indiscriminate geographies, sweeping acts of abstraction whose homogenizing effects make (counter)terrorist violence possible. 相似文献
84.
85.
The loess site at Boynychi (the Volyn Upland) is of essential importance for the stratigraphy of Middle and Upper Pleistocene
in Central Europe. The profile was recently dated by Fedorowicz and Prylypko in 2007 (parallel dating), and by Kusiak in 2009.
The Upper Vistulian loesses are much thicker in the exposure from 2009 than in the earlier examined one (2007). The list of
results obtained in the Gdańsk, Kiev and Lublin laboratories, respectively, can be divided in two. The first group contains
the results obtained for the Horohiv and Korshiv pedocomplexes and for the loess from the penultimate glacial, which separates
these pedocomplexes. The results from all laboratories are very similar and rather well describe the real age of dated deposits.
The second group contains the widely differing results of dating of the Vistulian loesses. The TL ages obtained by Fedorowicz
and Prylypko are considerably older than those obtained by Kusiak in the new exposure. The latter ones excellently correspond
to the geologic-stratigraphic interpretation of the profile. Two incompatible series of TL dating results indicate that local
variability of loess accumulation conditions in different stages of their formation may have resulted in incomplete luminescence
zeroing of mineral material before deposition. 相似文献
86.
Dendrochronological methods can be applied to the reconstruction of different types of environmental events such as climate changes, fires, glacier movements, floods, earthquakes, volcano activity. In the field of geomorphology dendrochronology is increasingly frequently used for the absolute dating of different types of mass-movements (rock falls, landslides and debris flows, etc.). Trees growing on slopes transformed by mass-movements are tilted and wounded while their stems and root systems are exposed or buried under sediment. These events are recorded in wood anatomy as eccentric growth, reaction wood, scar overgrowth by callous tissue, changes in cell size or adventitious root production. Dating changes in wood anatomy allows to date and precisely reconstruct the spatial and temporal occurrence of mass-movements with at least one year resolution. The paper provides a review of existing dendrochronological tools used in geomorphology and also an example of the application of eccentric tree-growth to reconstruct landsliding. Using tree-ring eccentricity allows to (1) obtain a dynamic depiction of slopes, (2) study landslide activity, not only contemporary, but also in the last tens of hundreds of years (depending on the stand age). 相似文献
87.
Danuta Michalska Anna Pazdur Justyna Czernik Małgorzata Szczepaniak Marta Żurakowska 《Geochronometria》2012,40(1):33-41
Lime mortars may contain carbon from different origins. If the mortars are made of totally burnt lime, radiocarbon dating yields the true age of building construction. The presence of carbonaceous aggregates gives the so-called dead carbon effect, which may generate older ages. Another source of carbon is charcoal present in mortars. An attempt has been made to apply the radiocarbon method to mortars of archaeologically estimated age from the Dead Sea region. Petrographical analyses of these samples show the carbonaceous character of the binder and large amounts of limestone aggregate. Determination of the mineral composition of the mortars and comparison with the geology of the surrounding, allows the provenance of the raw materials to be identified. They probably represent the Cretaceous rocks of the Judea Group. Separate radiocarbon dates were made on bulk mortar samples, binder, charcoal fragments and separated fractions from mortars. In the case of binder-aggregate mixture the reservoir effect correction has been applied. 相似文献
88.
Tomasz Płonka Krzysztof Kowalski Małgorzata Malkiewicz Jan Kuryszko Paweł Socha Krzysztof Stefaniak 《Journal of archaeological science》2011
An ornamented artefact made of antler, found in the environs of ?widwin (Pomerania, NW Poland), was subject to structural and environmental analysis. Radiocarbon dating (10?700 ± 60 BP or 10?910–10?680 cal. BC) places it in the Final Palaeolithic, at the end of Weichselian (boundary of the Allerød and Younger Dryas). The surface of the artefact bears a complex ornament of zigzag lines and an anthropomorphic drawing, representing most probably a woman with spread legs. Palynological analysis of the deposit in which the object was found indicates forest communities (pine-birch forests) with some open areas, in a cool climate. Ultrastructural examination points to the elk Alces alces (Linnaeus, 1758) as the source species; the antler was at the stage of intense growth which indicates that the elk was killed or died in the spring-summer period. The antler was large, and the object made of it was used for a long time, playing a role in rituals and symbolic culture of a hunting group. The ornamentation shows an affinity to the early Mesolithic art and makes it possible to better trace the relations between the hunters of the late Pleistocene and those of the early Holocene. 相似文献
89.
Maria Łanczont Andrij B. Bogucki Stanisław Fedorowicz Jarosław Kusiak 《Geochronometria》2011,38(4):350-358
The history of the interlaboratory comparison of TL dating results in Poland started in the 1980s. At that time the Lublin,
Warsaw and Silesian laboratories made the first attempts at TL dating of the same loess samples from the Odonów profile. However,
the cooperation ceased for many years due to great differences in the obtained TL age estimates. The next interlaboratory
comparisons were made in the years 2000–2009 for the loess samples from several Polish (Dybawka, Tarnawce, Dankowice, Biały
Kościół) and Ukrainian (Boyanychi, Halych, Velykyj Hlybochok, Yezupil) profiles. Most of the compared dates, obtained for
the loess deposits from the Upper Pleistocene and younger part of the Middle Pleistocene, were consistent. This encouraged
us to undertake the Gdańsk-Lublin interlaboratory cooperation in dating of 200-700 ka old loess deposits. Nine samples were
taken from the Ukrainian profile Mamalyha 2 in 2009 for this purpose. The TL dating results indicate that comparable dates
are obtained in two laboratories for loess deposits younger than 300 ka BP. The TL signal obtained in the Gdańsk laboratory
for the samples older than 300 ka BP was saturated so such samples should not be dated by the multi-aliquot regeneration method.
The results obtained in the Lublin laboratory for these deposits (489–682 ka) confirm that it is possible to date loess deposits
older than 500 ka. It probably results from the use of total-bleach method with preheating at 160°C for the equivalent dose
determination. 相似文献
90.
Absolute dating using luminescence methods is widely applicable in geology, geomorphology, palaeogeography and in archaeology
in establishing ages of sediments and archaeological artefacts. By creating absolute time scales for different events in the
history of Earth scientists are able to reconstruct changes in climate and environment in the past, and the history of colonization
and development of culture. 相似文献