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This paper aims at a greater comprehension of the distribution of differentiated knowledge bases and their association with innovation performance. Drawing on evolutionary economic geography, we applied a combinatorial and dynamic view on knowledge bases. The main contribution is the examination of changes and transformations of knowledge bases over time in particular group of regions in Europe and links with innovation performance. Our study revealed systematic regularities between regions with different innovation performance and their knowledge bases. With decreasing regional innovation performance the volatility of knowledge bases over time increases. Innovation leaders evinced stability over time and the most balanced composition of knowledge bases (compared with Central and Eastern Europe regions). Western European countries and regions exhibit the most balanced structure of knowledge bases. An important complementarity and synergy has been identified in the close relatedness of the symbolic knowledge base to the analytical knowledge base. The highest intensity of SME cooperation takes place in regions with a strong analytical base and in regions with the most balanced mix among all three bases (particularly in the UK, the Netherlands and Belgium. Underperforming in innovation show a balanced mix of synthetic and symbolic knowledge bases.  相似文献   
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Over six months in 1861, Commander Birilëv of the Russian Navy constructed a base on the island of Tsushima and attempted to negotiate with local domain officials to turn the island into a Russian protectorate. While official Japanese documents, including Tsushima reports to the Tokugawa government in Edo, claim they vigorously resisted these most unwelcome Russian efforts, Birilëv records the Tsushima officials themselves as the ones who first requested Russian patronage. How can we reconcile these two dramatically different versions of the same event? Due to the relatively isolated position of Tsushima, separated from mainland Japan by the sea, the Russians incorrectly believed they were dealing with a borderland that could be detached from the Tokugawa polity, or even with an independent state, tied to Japan merely by flimsy ‘feudal’ bonds. At the same time, Tsushima officials, afraid of antagonizing the volatile Birilëv, resorted to various stratagems that were misinterpreted by him as signals of desire to switch feudal overlords. The resultant negotiations reveal much about international diplomacy across different political cultures in mid-19th century Asia, the influence of Russia on the development of the Japanese polity, and the conduct of gunboat diplomacy at the apogee of European imperialism.  相似文献   
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The leprosy known today primarily from tropical areas was a relatively common disease in European Middle Ages. This article describes two skeletons bearing palaeopathological indications of leprosy from a cemetery at ?atec in North-West Bohemia (Czech Republic). The archaeological context clearly shows that these individuals were buried prior to the second decade of the 12th century, and most probably in the second half of 11th century. This rules out the possibility that these individuals might have contracted the disease in connection with the Crusades, in which a Bohemian contingent under Prince Vladislav II participated from 1141 to 1142. Molecular genetic methods were applied to detect specific DNA fragments of the causative agent of leprosy, Mycobacterium leprae. The nasal concha of one individual yielded DNA that could be directly sequenced after isolation and amplification. The vertebral body of the second individual, on the other hand, did not provide DNA of sufficient quality for direct sequencing and only weak amplification was detectable. The morphological and genetic analyses both indicate that leprosy existed prior to the Crusades in medieval Bohemia, albeit that its prevalence was probably not as great as in northern or western Europe.  相似文献   
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The author argues against the widespread view (stated in several articles in Soviet Geography) that labor-intensive industries should be kept out of Siberia because of the shortage of labor resources in that region. Taking the specific example of labor-intensive machinery industry such as instrument-making, as opposed to steel-intensive industry, he points out that labor-intensive plants, by virtue of their smaller size, usually have smaller labor requirements than large heavy-machinery manufacturing plants. Moreover, he argues, location must not be based on total population or total labor resources of a region, but on the availability of so-called free (nonemployed) labor resources, which consist largely of women and of young people just entering upon a career. This category of labor resources happens to be greater in the eastern regions than in the western regions of the Soviet Union. In fact, one reason for the net out-migration from Siberia, according to the author, is that second and third members of households find it difficult to obtain jobs in a regional economy that is largely oriented toward male employment (in extractive industry, timber felling, etc.). The introduction of labor-intensive industries into existing Siberian industrial complexes would thus help provide employment to other household members and eliminate one reason for out-migration.  相似文献   
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This paper aims at the comprehension of feasible development trajectories conceptualized within the new path-development model in the case of two less developed regions in Central Europe (CE). The main new element of this paper comprises the examination of the perception of key barriers and mechanisms hindering particular evolutionary trajectories by regional stakeholders and their comparison with those conceptualized in the literature. Although conceptual characteristics of prevailing path types in different regional innovation systems do exist, empirical verification from less developed regions such as those in CE is insufficient. On the basis of interviews with regional stakeholders, a typology of barriers for pathways conceptualized to date was elaborated from a CE perspective. Our study showed that the feasibility of a more radical path is hindered by a wide range of barriers operating at different levels. The elaborated typology of barriers for various path-development trajectories outlined the main hindrances constraining key regional actors, linkages and institutions. Given the general weakness of the overall RIS, path-extension and path-modernization trajectories are bound to be the most realistic options for this type of less developed regions. Our study revealed existing regional dynamics as built predominately upon incremental changes within rooted but prospective industrial branches.  相似文献   
6.
We estimate the impact of internal migration on job‐match quality for recent Dutch university and college graduates. We find positive yet modest wage returns. After controlling for the self‐selection of migrants with an IV approach, this effect is no longer significant for university graduates and all graduates from peripheral areas. We also find that, for our alternative job‐match measures, where there is evidence of migrant self‐selection, controlling for self‐selection strongly reduces the effect of internal migration on job‐match quality. In some cases, the returns on internal migration are found to be negative, which may signal forced migration.  相似文献   
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Gi?ka, W., Zakrzewska, M., Baranov, V., Wang, B. &; Stebner, F., May 2016. The first fossil record of Nandeva Wiedenbrug, Reiss &; Fittkau (Diptera: Chironomidae) in early Eocene Fushun amber from China. Alcheringa 40, xxx–xxx. ISSN 0311-5518

The first fossil representative of the extant chironomid genus Nandeva Wiedenbrug, Reiss &; Fittkau, 1998 Wiedenbrug, S., Reiss, F. &; Fittkau, E.J., 1998. Nandeva, gen. nov., a new genus of Chironomini (Insecta, Diptera, Chironomidae). Spixiana 21, 5968. [Google Scholar] is described based on a specimen found in early Eocene (50–53 Ma) Fushun amber from China. The adult male of Nandeva pudens sp. nov. has the long RM vein as a continuation of M and R4+5, the bare squama, the strongly reduced anal area of the wing and hypopygial characters typical of extant species of the genus. Following the systematic concept based on adult male morphology and characters examinable in fossil specimens, we present N. pudens as a possible member of the Tanytarsini, arguing that Nandeva is part of this tribe or a possible sister group to the tribe. This is the first record of Nandeva from the Palaearctic region.

Wojciech Gi?ka [] University of Gdańsk, Department of Invertebrate Zoology and Parasitology, Wita Stwosza 59, 80-308 Gdańsk, Poland; Marta Zakrzewska [] University of Gdańsk, Department of Invertebrate Zoology and Parasitology, Wita Stwosza 59, 80-308 Gdańsk, Poland; Viktor Baranov* [] Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany; Bo Wang? [] Chinese Academy of Sciences, Nanjing Institute of Geology and Palaeontology, State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing 210008, PR China; Frauke Stebner [] University of Bonn, Steinmann-Institute, Section Palaeontology, Nussallee 8, 53115, Bonn, Germany. *Also affiliated with Humboldt University of Berlin, Faculty of Mathematics and Natural Sciences, Geography Department, Rudower Chaussee 16, 12489 Berlin, Germany. ?Also affiliated with Chinese Academy of Sciences, Institute of Zoology, Key Laboratory of Zoological Systematics and Evolution, Beijing 100101, PR China.  相似文献   
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The discovery and excavations in 2006 by joint Russian–German–Mongolian expeditions of the Pazyryk culture burial sites (4th to 3rd centuries BC, Early Iron Age, the Scythian period) in the Altai mountains of northwestern Mongolia near the Russia border provided new material for studying various aspects of these ancient peoples lives, including human, animal and plant remains. Ice accumulation in the graves preserved the human remains, allowing biological analysis of the samples. We conducted a genetic study based on mitochondrial DNA from remains of three Pazyryk culture representatives to investigate the possible genetic relationships of this Siberian Scythian group with populations of adjacent territories. These data support possible genetic contacts between populations of Altai and other Eurasia regions in the Early Iron Age, and are in good agreement with corresponding archaeological and anthropological data. However, a large-scale study of the Pazyryk population gene pool structure must be performed to further confirm these findings.  相似文献   
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