The survival of PCR-amplifiable DNA in cow leather

We have investigated the survival of PCR-amplifiable mitochondrial and nuclear DNA in a small number of modern and medieval bovine leather samples. The results of this preliminary investigation demonstrate that, while no nuclear DNA can be PCR-amplified from any of the specimens, mitochondrial DNA can be amplified from all samples. To investigate this contrasting pattern of DNA survival further, we have vegetable-tanned cow skin in our own laboratory, and directly assayed the survival of PCR-amplifiable mitochondrial and nuclear DNA at each step of the process. The results indicate that nuclear DNA is reduced to sub-amplifiable levels as a result of the tanning baths, whereas amplifiable mitochondrial DNA survives the complete process. Our results suggest that old and archaeological bovine leather may represent a useful source of genetic information, although this information will most likely be limited to that which can be gained from mitochondrial DNA.     

Das Klima von Bayreuth

Zusammenfassung Das Klima von Oberfranken liegt in einem übergangsbereich zwischen ozeanisch und kontinental gepr?gten Klimaten. Der Beitrag stellt langj?hrig ermittelte Klimadaten und Klimatrends für die Stadt Bayreuth vor. Er geht auf die Herausforderungen ein, die sich daraus für die Stadtplanung ergeben, auch und besonders im Zusammenhang mit dem Klimawandel.     

New light on early caprine herding strategies from isotope analysis: a case study from Neolithic Anatolia

The measurement of stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes of caprine bone collagen from the Neolithic sites of Çatalhöyük and Aşıklı Höyük in south-central Anatolia have allowed examination of exploitation and herding practices of sheep and goats. The isotope values from protodomestic caprines at Aşıklı Höyük suggests that these animals were consuming very similar foods to each other and were all confined to the same or similar environments with no access to C₄ plants. At Çatalhöyük, the results show how the caprine management strategy develops from the strategy seen at Aşıklı Höyük into a more varied practice at an early stage as the site grows with an increasing dietary contribution obtained from C₄ plants. No change in diet is isotopically discernible at Aşıklı Höyük. Interestingly, no distinction could be made between the diets of sheep and goats at either site. Therefore, such studies are a useful method of examining the development of early herding or management strategies of caprines in the Near East.     

Radiocarbon dating of prehistoric hearths in alpine northern Sweden: problems and possibilities

The chronology of prehistoric Sami settlement sites has previously been established by conventional radiocarbon dating of bulk charcoal samples associated with hearths from sunken hut floors (stállo-foundations). Here we present results of a comprehensive dating exercise of stállo-foundations in the alpine area of northern Scandinavia using Accelerator Mass Spectrometry (AMS) radiocarbon dating of charcoal. Over a 3 km² study area, AMS calibrated ages of hearth charcoal from 22 stállo-foundations across 12 sites securely date these features to between cal. AD 640 and AD 1180. Only small variations in age were found between charcoal samples from different areas of a given hearth. Statistical analysis of all the charcoal AMS radiocarbon dates obtained reveals that 12 stállo-foundations across nine sites are contemporaneous and date to the Viking Period (AD 800–AD 1050). The tightly constrained AMS-based chronology of stállo-foundations contrasts with the existing chronology based on conventional radiocarbon analysis, which places these features within a significantly greater time-frame of between AD 600 and AD 1900, with most dates ranging between AD 800 and AD 1350.This discrepancy is likely to result from the necessity of collecting composite hearth charcoal particles, which may originate from different phases of occupation, in order to achieve the required final carbon content for conventional radiocarbon analysis. We argue that the new AMS-based radiocarbon chronology of stállo-foundations presented here supersedes the existing chronology based on conventional (Gas Proportional counting) radiocarbon analysis and we advocate the use of AMS radiocarbon dating in future hearth investigations.     

An Insider's Look into Policy Transfer in Transnational Expert Networks

Much of the recent academic literature on spatial planning in Europe focuses on either cross-national comparison of planning frameworks and planning practices or on transnational and transregional initiatives and their impact on planning in European countries. From those publications, it can be gleaned how similar themes are translated differentially in different national contexts. Although it is also a great source of European integration and harmonization, the phenomenon of the knowledge exchange within transnational expert networks of European planners at the level of cities has received less attention. In this paper, the knowledge exchange among planners in such a network is studied, highlighting the role of “transfer agents” (academic and/or policy experts operating in communities in different policy arenas) in the exchange process. It builds on the insights from existing literature on policy transfer and policy learning, and tries to add a new perspective on this body of literature from an insiders' perspective, i.e. participatory observation. The idea is that policy transfer can be fruitfully approached as a process of knowledge and information transfer between producers, senders, facilitators and recipients. Often this exchange is to a very large extent a process of absorbing appealing labels for policy solutions from the international or national policy levels, and then adopting an interpretation of it suitable to one's own context. The authors try to give meaning to this exchange process by using two mechanisms, i.e. social interaction and conceptual replication. By combining these two mechanisms the authors try to uncover which policy lessons are being transferred among seven European cities that joined the expert network on European sustainable urban development (Pegasus).