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1.
This paper demonstrates the positive effect of immigrant entrepreneurs on manufacturing exports over and above that of diasporas. Using small-scale regional administrative data, our instrumental variable estimates of export gravity models imply that ceteris paribus, that is, holding constant the total number of immigrants, the expected protrade effect of a migrant becoming an entrepreneur amounts to an average increase of US$5,946 in the export flows toward her country of origin. Besides these dyadic effects, immigrant entrepreneurs unlike nonentrepreneurial immigrants raise a region's overall competitiveness and export flows toward other destinations as well.  相似文献   
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This article presents and discusses the chronological layout of the final Mousterian and Uluzzian levels of Fumane Cave in northern Italy using 14C, ESR and TL methods. Given its complex sedimentary and cultural succession, Fumane is a key site to assess the Middle–Upper Palaeolithic transition in Southern Europe and to explore Neanderthal behaviour and to compare it with the first Aurignacians. Large ranges defined by the ESR and TL dates cover the radiocarbon ages for units from A11 to A4, respectively, from 42.8 to 32.5 ka BP become progressively younger in agreement with the stratigraphy, despite high dispersions within the same unit. Our estimates using chronometric data seem to support the hypothesis that the sequence may cover almost 10,000 radiocarbon yr and that from comparison with the sedimentological and palaeoecological data, the late Middle Palaeolithic and the early Upper Palaeolithic at Fumane occur in sediments formed under moderately cool to mild climatic conditions correlated to the Hengelo-Interstadial, shifting towards cooler and drier conditions. Finally, comparisons between the Fumane data set and other sites in the North-Adriatic region are discussed.  相似文献   
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The construction of the Baptistry of Saint John has a debated and uncertain history; the hypothesis on its main construction phases may span from the Roman period to the 13th century, according to different authors. This uncertainty is mainly due to the lack of primary sources and certain dating issues. By combining dendrochronological analysis and radiocarbon dating, some light was shed on the building’s history. Open at least from 897, in 1059 Pope Nicholas II re-consecrated the baptistry after several renovations. Around that period, the octagonal dome was probably built by using chestnut beams to tie the structure together. The dendrochronological analysis dated the silver fir element to 1268. This element possibly represents a replacement coincident with the period, between 1270 and 1300, when a substantial part of the mosaics of the dome was positioned.  相似文献   
4.
The characterization of organic residues found in ceramics objects coming from the Carmine Convent in Siena (Central Italy), probably built in the second half of the 13th century, is described. The nine objects analyzed in this study are pots, casseroles, and lids and they were used as filling material of the vault of one room of the convent.  相似文献   
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The article focuses on the feature of the Lega Nord's (LN) electoral advance into new Italian regions, by stressing the similarities and differences with its historical bases of support. In order to verify whether the expansion has followed a common pattern in historical and well-defined territories of the leghista settlement, results of flow-of-votes analysis in eight different sub-areas of two Northern regions (Emilia-Romagna and Veneto), are reported. Data makes empirically credible the hitherto suggestion of a LN breakthrough among new sectors of the electorate. Estimations of vote shifts show both signals of electoral continuity, and change. While in Veneto no radical change in LN's voters profile occurred, indications from flow-of-votes in Emilia-Romagna has detected a statistically significant (even if minor) flow from the center-left parties.  相似文献   
6.
The identification of the organic residues preserved in archaeological materials yields good insights into understanding food production, trade and consumption. Wine is one of the most important beverages produced, traded and consumed in the Mediterranean area. Consequently, it is important to identify its presence in ancient materials. Nevertheless, the identification of wine markers is still an object of discussion. We present here the results obtained from analysing different materials using gas chromatography/mass spectrometry (GC/MS), which allowed for the identification of tartaric acid and other markers of wine. The method was first tested on experimental and traditional materials that have been used until recently to store and/or produce wine and was then used for investigating archaeological materials. The experiments also involved the degradation of wine through cooking, drastic heating and burial for seven years. The results from the analysis of ceramic and plaster materials are discussed.  相似文献   
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The recent literature on “complex contagions” challenges Granovetter’s classic hypothesis on the strength of weak ties and argues that, when the actors’ choice requires reinforcement from several sources, it is the structure of strong ties that really matters to sustain rapid and wide diffusion. The paper contributes to this debate by reporting on a small-N study that relies on a unique combination of ethnographic data, social network analysis, and computational models. In particular, we investigate two rural populations of Indian and Kenyan potters who have to decide whether to adopt new, objectively more efficient and economically more attractive, technical/stylistic options. Qualitative field data show that religious sub-communities within the Indian and Kenyan populations exhibit markedly different diffusion rates and speed over the last thirty years. To account for these differences, we first analyze empirically observed kinship networks and advice networks, and, then, we recreate the actual aggregate diffusion curves through a series of empirically calibrated agent-based simulations. Combining the two methods, we show that, while single exposure through heterophilious weak ties were sufficient to initiate the diffusion process, large bridges made of strong ties can in fact lead to faster or slower diffusion depending on the type of signals circulating in the network. We conclude that, even in presence of “complex contagions,” dense local ties cannot be regarded as a sufficient condition for faster diffusion.  相似文献   
10.
Kaitag textiles, named after the Kaitag district of Southwest Daghestan, Russia, where it is being manufactured, are a unique embroidered textile art form. They were used by families on special occasions such as the birth, marriage or death of one of their members and were thus passed down from generation to generation as family heirlooms. Today, only a few hundred of these precious antique specimens can still be found, and surviving examples are mostly from the seventeenth and eighteenth centuries. In this article, an extensive work for the scientific analysis of Kaitag textiles is presented as the logical continuance and updating of the investigations performed by thin layer chromatography almost two decades ago. A multi-technique approach involving the combined use of micro-invasive and nondestructive techniques suitable for in situ analyses was used, aiming to identify the colourants of Kaitag textiles and the inks employed for the underlying drawing. Analyses were performed by high-performance liquid chromatography, surface-enhanced Raman spectroscopy, scanning electron microscopy combined with energy dispersive X-ray analysis, as well as visible reflectance spectroscopy and X-ray fluorescence. In addition, infrared reflectography and ultraviolet fluorescence were employed to visualise underlying drawings and possible restorations. Corrosion phenomena observed in brown- and black-dyed areas were also investigated.  相似文献   
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