Determining a reliable method to detect life on another planet is an essential first step in the pursuit of discovering extraterrestrial life. Polyhydroxyalkanoates (PHAs), bioplastic polymers created by microorganisms, are strong candidates for defining the presence of extraterrestrial life due to their water insolubility, strong ultraviolet resistance, high melting points and high crystallinity, amongst other qualities. PHAs are abundant on Earth, and their chemical properties can easily be distinguished from non-biological matter. Their widespread distribution and conferred resistance to astrobiologically relevant extreme environments render PHAs highly favourable candidates for astrobiological detection. Integrating detection of PHA biosignatures into current and future life-detection instruments would be useful for the planetary search for life. PHAs are analysed and characterized in laboratories by gas chromatography-mass spectrometry, infrared spectroscopy, Raman spectroscopy and immunoassay analysis in addition to other methods. We outline a path forward to integrate PHA detection in astrobiology missions to aid the search for extraterrestrial life.

This study relies on a linear programming model to estimate welfare ratios in Spain between 1600 and 1800. This method is used to find the food basket that guaranteed the intake of basic nutrients at the lowest cost. The estimates show that working families in Toledo had higher welfare ratios than in those in Barcelona. In addition, the welfare ratios of Spain were always below those of London and Amsterdam. The divergence between Northern Europe and Spain started before the Industrial Revolution and increased over time.

Deer hunting was heavily ritualized in medieval Europe, as indicated by historical and archaeological evidence; it also emphasized social differentiation. The butchery of a deer carcass (‘unmaking’) was integral to the ritual and led to different body parts being destined for individuals of differing status. Archaeologically, the practice is particularly visible in high-status sites in Britain, but documentary and archaeological sources are consistent in pinpointing its earliest occurrence in twelfth-century France. In Italy, late medieval evidence for such ‘unmaking’ is present but is not supported by any known historical sources. Red and fallow deer were butchered in a formalized manner, whereas the data for roe deer are unclear. Although the Normans contributed to the diffusion of the ‘unmaking’ practice, in France it is also found outside the core area of Norman influence. The extensive spread of the practice demonstrates the connectedness of the medieval hunting culture in Europe.

States require money to function and therefore every government has to continuously raise new funds. On the financial markets, governments cannot be sure that auctions of their debt will be sufficiently attractive to financial investors, which is why they usually enter into cooperative agreements with selected banks. The best known and most widespread form of cooperation is the primary dealer system. A primary dealer is a bank that commits to purchasing a certain percentage of government debt at each auction and to intervene as a formalized market maker in the debt market if necessary. Most of the primary dealer systems involve the banks being financially neither remunerated nor compensated for their activities, and if there is some kind of financial compensation, it is on a low level. The article analyses European primary dealer systems and asks why banks are willing to participate in these systems. I will show that both domestic and foreign banks use their status as primary dealers to build long-term relationships with one or more European governments and to gain an advantage on the global stage. In Bourdieu’s terms, primary dealer banks use their financial capital to accumulate social and symbolic capital.

Tall, spiky snow structures (penitentes) occur high in subtropical mountains, in the form of blades oriented east-west and tilted toward the noontime sun. By trapping sunlight, they cause a reduction of albedo by ~0.3 relative to flat snow. The formation of penitentes, explained by Lliboutry in 1954, requires weather conditions allowing the troughs to deepen rapidly by melting while the peaks remain dry and cold by sublimation, losing little mass, because of the 8.5-fold difference in latent heats. Lliboutry's explanation has been misrepresented in some recent publications. A concern has been raised that in the low latitudes of Jupiter's moon Europa, the ice surface may have developed penitentes, which would pose a hazard to a lander. They would require a different mechanism of formation, because Europa is too cold for melting to occur. If penitentes are present on Europa, they cannot be resolved by the coarse-resolution satellite images available now, but the high albedo of Europa (~0.7 at visible wavelengths) argues against the existence of such extreme roughness.

The authors of this article consider the relationship in European prehistory between the procurement of high-quality stones (for axeheads, daggers, and other tools) on the one hand, and the early mining, crafting, and deposition of copper on the other. The data consist of radiocarbon dates for the exploitation of stone quarries, flint mines, and copper mines, and of information regarding the frequency through time of jade axeheads and copper artefacts. By adopting a broad perspective, spanning much of central-western Europe from 5500 to 2000 bc, they identify a general pattern in which the circulation of the first copper artefacts was associated with a decline in specialized stone quarrying. The latter re-emerged in certain regions when copper use decreased, before declining more permanently in the Bell Beaker phase, once copper became more generally available. Regional variations reflect the degrees of connectivity among overlapping copper exchange networks. The patterns revealed are in keeping with previous understandings, refine them through quantification and demonstrate their cyclical nature, with additional reference to likely local demographic trajectories.

Materiality has been largely left out of the study of Muslim life in Europe, and limited to an etic rather than emic approach. In this paper, I analyse a conservative London mosque community (the East London Mosque) that depends on the material––what I term “ethical substance”––to reinforce its ascetic rejection of the world. Drawing from five months of ethnographic research in this mosque, I examine three aspects of materiality––clothing, the mosque building, and technology––in order to explore how the community negotiates its position in the city at hand, as well as more broadly vis-à-vis modernity. The mosque emerges as a site of discursive-material tension where ethics and locale intersect, and where intention (niyya) matters more than the constitution of objects. It elucidates European modernity as broader than liberal democratic ideals (i.e. in a community stressing a returns towards, rather than away from, tradition).

This monographic issue of the RHE-JILAEH presents new case studies in order to compare regions of Asia, Europe and the Americas through analysis of global demand for western goods in China (goods of European and American origin) as well as demand eastern goods (of Chinese and Indian origin) in Europe and the Americas. The global circulation of goods included accumulation of American silver in the hands of Chinese merchants and private institutions. Thus, this issue re-evaluates origins of the first globalisation during the 16th century, as opposed to the 1820s. Global trade networks and long-distance alliances in Asia, the Americas and Europe date back to the 16th century when Manila galleon routes were established.

Bog bodies are among the best-known archaeological finds worldwide. Much of the work on these often extremely well-preserved human remains has focused on forensics, whereas the environmental setting of the finds has been largely overlooked. This applies to both the ‘physical’ and ‘cultural’ landscape and constitutes a significant problem since the vast spatial and temporal scales over which the practice appeared demonstrate that contextual assessments are of the utmost importance for our explanatory frameworks. In this article we develop best practice guidelines for the contextual analysis of bog bodies, after assessing the current state of research and presenting the results of three recent case studies including the well-known finds of Lindow Man in the United Kingdom, Bjældskovdal (Tollund Man and Elling Woman) in Denmark, and Yde Girl in the Netherlands. Three spatial and chronological scales are distinguished and linked to specific research questions and methods. This provides a basis for further discussion and a starting point for developing approaches to bog body finds and future discoveries, while facilitating and optimizing the re-analysis of previous studies, making it possible to compare deposition sites across time and space.

In this article I address the relationship between European archaeologists and the European Union and argue that the dominant attitude of non-involvement that archaeologists have embraced over the past decades cannot be justified given recent political developments. The European project finds itself in a state of deep crisis, under siege from populist and far-right leaders within and around Europe. We cannot afford to watch from the sidelines when the future of hundreds of millions of people is at stake. As archaeologists we can make a positive contribution by harnessing the political dimension of our work, which we need to stop seeing in a negative light. We should deploy the past to help tackle the challenges of our society. European archaeologists should particularly focus on developing grand narratives of a shared past in Europe, to act as a foundation for a European identity.

This study examines the role of the strength of the Intellectual Property (IP) institutions of 23 European countries in attracting Chinese Outward Foreign Direct Investment (OFDI) during the time period 2003–2015. Following a dynamic panel data analysis methodology, we find that the strength of IP institutions has a positive effect in attracting higher levels of OFDI from China. This is an important finding for the OFDI literature from emerging markets, since previous studies have researched this relationship from the OFDI perspective of developed countries. However, we also find a weak indication of a potential U-shaped relationship between the strength of IP institutions and Chinese OFDI. To better understand this relationship, we interact a European country's membership in the Former Eastern Bloc (FEB) with the strength of IP institutions and find a negative moderating effect. We therefore find that when investing in FEB countries, Chinese firms are attracted to weaker levels of IP institutional strength. The results of this study have important implications for future studies on the determinants of OFDI from emerging markets, as well as for European and Chinese businesses and policy-makers concerning the importance of IP institutional strength.

The development of algorithms for agile science and autonomous exploration has been pursued in contexts ranging from spacecraft to planetary rovers to unmanned aerial vehicles to autonomous underwater vehicles. In situations where time, mission resources and communications are limited and the future state of the operating environment is unknown, the capability of a vehicle to dynamically respond to changing circumstances without human guidance can substantially improve science return. Such capabilities are difficult to achieve in practice, however, because they require intelligent reasoning to utilize limited resources in an inherently uncertain environment. Here we discuss the development, characterization and field performance of two algorithms for autonomously collecting water samples on VALKYRIE (Very deep Autonomous Laser-powered Kilowatt-class Yo-yoing Robotic Ice Explorer), a glacier-penetrating cryobot deployed to the Matanuska Glacier, Alaska (Mission Control location: 61°42′09.3″N 147°37′23.2″W). We show performance on par with human performance across a wide range of mission morphologies using simulated mission data, and demonstrate the effectiveness of the algorithms at autonomously collecting samples with high relative cell concentration during field operation. The development of such algorithms will help enable autonomous science operations in environments where constant real-time human supervision is impractical, such as penetration of ice sheets on Earth and high-priority planetary science targets like Europa.

The primary aim of this review is to highlight that sea-ice microbes would be capable of occupying ice-associated biological niches on Europa and Enceladus. These moons are compelling targets for astrobiological exploration because of the inferred presence of subsurface oceans that have persisted over geological timescales. Although potentially hostile to life in general, Europa and Enceladus may still harbour biologically permissive domains associated with the ice, ocean and seafloor environments. However, validating sources of free energy is challenging, as is qualifying possible metabolic processes or ecosystem dynamics. Here, the capacity for biological adaptation exhibited by microorganisms that inhabit sea ice is reviewed. These ecosystems are among the most relevant Earth-based analogues for considering life on ocean worlds because microorganisms must adapt to multiple physicochemical extremes. In future, these organisms will likely play a significant role in defining the constraints on habitability beyond Earth and developing a mechanistic framework that contrasts the limits of Earth's biosphere with extra-terrestrial environments of interest.

‘European archaeology’ is an ambiguous and contested rubric. Rooted in the political histories of European archaeology, it potentially unites an academic field and provides a basis for international collaboration and inclusion, but also creates essentialized identities and exclusionary discourses. This discussion article presents a range of views on what European archaeology is, where it comes from, and what it could be.