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111.
Michael Schiffer’s theoretical and methodological contributions to archaeology are substantial. For the last two decades, Schiffer has become increasingly interested in the history of electrical technology, including portable radios, electric automobiles, eighteenth-century electrostatic technology, and, most recently, nineteenth-century electric light and power systems. Schiffer has long held a behavioral view, which focuses analytical attention on interactions between humans and material things, including complex technological systems (CTSs). For Schiffer, two key aspects of the evolution of CTSs are stimulated variation, defined as an increase in invention resulting from changing selective conditions, and cascading, defined as sequential spurts of invention that occur through the recognition of emergent performance problems in a CTS. To attain maximum usefulness, these concepts should be placed in a modern evolutionary framework that correctly identifies, and does not oversell, the role played by cultural selection. Research on individual and social learning provides the critical link between Schiffer’s stimulated variation and cascade models and the diffusion of CTSs.  相似文献   
112.
The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River. The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001. 160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and 7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10th–15th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing standard chronology or to create a long floating average treering curve.  相似文献   
113.
Determination of the source of Spondylus objects is essential for the interpretation of Late Neolithic exchange systems and the social role of shell ornaments. We performed stable isotope analysis combined with cathodoluminescence microscopy study on ornaments (beads, bracelets) made of Spondylus shells excavated at the Aszód-Papi földek archaeological site in Hungary, to define their origin. For comparison Spondylus finds from Neolithic sites of Greece, modern Spondylus shells from the Aegean and the Adriatic, as well as fossil Spondylus and Ostrea shells from the Carpathian Basin were also examined. Oxygen isotope composition of Spondylus finds from Aszód ranges between ?1.9 and 2.1‰ and overlaps with the oxygen isotope range of shell objects from other Neolithic sites. Modern Spondylus shells from the Aegean and the Adriatic show overlapping δ18O values with one another and with the Neolithic objects; while recent shells of the Black Sea clearly are separate isotopically from the Mediterranean ones and most of archaeological artefacts. Spondylus shells from the Aszód site have Mediterranean origin; their source can be the Aegean or the Adriatic. Based on a former strontium isotope study the use of fossil Spondylus shells is excluded as raw material used for ornaments, however, in recent years the use of fossil shells was reintroduced. The shell ornaments from Aszód-Papi földek and the fossil oyster shells collected from the Carpathian Basin exhibit some overlapping oxygen isotope values; however, cathodoluminescence microscopy indicates that the Spondylus objects retained their original aragonite material. Diagenetic calcite, which occurs typically in the fossil shells, was not detected in the ornaments suggesting that the studied objects were made of recent shells. Calcitic parts observed in some Spondylus objects are not related to fossilisation.  相似文献   
114.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
115.
Ji?í (George) Procháska (1749–1820), a Czech anatomist, physiologist, and neuroscientist of the eighteenth century, ranks among the major figures of Czech and European cultural history. The works of Ji?í Procháska, due to historical circumstances, were published mostly in Latin and only some in German. However, given that only one treatise was partially translated into English, the results of his extensive research activities are currently unavailable to the international scientific community. The achievements of Ji?í Procháska undoubtedly belong to the major intellectual heritage of European science and certainly deserve attention as such, although his research reflected the time in which he lived and therefore has been reevaluated by later researchers. Undoubtedly, it is our duty not only to remember the work and legacy of Ji?í Procháska, which significantly influenced the development of our knowledge, but also to try to critically assess his contribution in terms of today. This article surveys the important biographical events of Ji?í Procháska’s life, taking into account the significance of his research.  相似文献   
116.
117.
The Royal Artillery Factory of Seville in Spain originated from pre‐existing private bronze foundries dating from the 16th century. The paper analyses the stratigraphy of wall cladding in the areas traditionally known as the ‘Old Foundry’ and the ‘New Foundry’, through its characterization by optical microscopy, scanning electron microscopy with energy‐dispersive X‐ray spectrometry (SEM‐EDX), micro‐X‐ray fluorescence (μ‐XRF) and micro‐X‐ray diffraction (μ‐XRD), in order to analyse the metal deposits that have accumulated since the 17th century. The data obtained allowed the verification of the available historiographical information and the location of the original bronze smelting furnaces. The analysis of patinas deposited on the overlapping layers of lime also confirmed that neither the raw materials nor the composition of the alloys used presented any substantial changes.  相似文献   
118.
Epistemic communities are an established concept in the study of international relations but can also explain policy change at the domestic level. This article asks why some epistemic communities manage to convince decision makers of their preferred policies while others do not. It suggests that the reason lies in the causal mechanism of epistemic communities' influence on decision makers, mediated by decision makers' demand for expert input. Most epistemic communities scholarship focuses on single case studies where the communities' influence on policy was strong and clear, leading to an overestimation of the groups' influence. To help correct this probable bias, this article compares a successful case of epistemic community influence (health technology assessment in Poland) with an unsuccessful example of the same policy (in the Czech Republic). The juxtaposition allows for unpacking of the necessary parts of the causal mechanism (emergence of an epistemic community, its activity, access to decision makers, and successful suasion) and separating them from the crucial scope condition. Decision makers' uncertainty about the policy issue at hand has traditionally been the key scope condition for epistemic communities but the successful Polish case demonstrates that epistemic communities can be influential even in highly certain areas of routine policymaking, leading to a reconceptualization of uncertainty as policymakers' demand for expert input. Demand can originate from various sources, but any change of it affects individual parts of the causal mechanism, leading to a success or failure of epistemic communities' policy enterprise.  相似文献   
119.
120.
The full release and circulation of excavation results often takes decades, thus slowing down progress in archaeology to a degree not in keeping with other scientific fields. The nonconformity of released data for digital processing also requires vast and costly data input and adaptation. Archaeology should face the cognitive challenges posed by digital environments, changing in scope and rhythm. We advocate the adoption of a synergy between recording techniques, field analytics, and a collaborative approach to create a new epistemological perspective, one in which research questions are constantly redefined through real-time, collaborative analysis of data as they are collected and/or searched for in an excavation. Since new questions are defined in science discourse after previous results have been disseminated and discussed within the scientific community, sharing evidence in remote with colleagues, both in the process of field collection and subsequent study, will be a key innovative feature, allowing a complex and real-time distant interaction with the scholarly community and leading to more rapid improvements in research agendas and queries.  相似文献   
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