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51.
Oxygen is a key parameter in the degradation of archaeological material, but little is known of its dynamics in situ. In this study, 10 optical oxygen sensors placed in a 2 m deep test pit in the cultural deposits at Bryggen in Bergen have monitored oxygen concentrations every half hour for more than a year. It is shown that there is a significant spatial and temporal variation in the oxygen concentration, which is correlated to measured soil characteristics, precipitation, soil water content and degradation of organic material. In these deposits oxygen typically occurs when the air content of the soil exceeds 10–15% vol, while oxygen dissolved in infiltrating rainwater is of less importance for the supply of oxygen in the unsaturated zone.  相似文献   
52.
Twenty‐six samples from domestic assemblages of 9th–12th century Córdoba were subjected to electron microprobe analysis. The results reveal two main compositional types. The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high‐impurity sand, and has some contemporary parallels from Syria and Egypt. The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels. These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world.  相似文献   
53.
This paper compares left-wing Latin American populism with Donald Trump. Despite their different social bases and economic policies, they use a similar logic to construct politics as an antagonistic struggle between two camps. Left-wing and right-wing populists aim to rupture existing political institutions to give power to the people, yet they differ in how they construct this category. Whereas Trump used ethnic criteria to differentiate the people from three out groups – Mexicans, Muslims, and African-American militant organisations – left-wing Latin American populists used political and socio-economic criteria. Despite their democratising promises, Latin American populists like Hugo Chávez in Venezuela and Rafael Correa in Ecuador undermined democracy from within. Even though stronger institutions might protect American democracy, Trump has disfigured democracy.  相似文献   
54.
Field courses are essential for subjects like Earth Sciences, Geography and Ecology. In these topics, GIS is used to manage and analyse spatial data, and offers quantitative methods that are beneficial for fieldwork. This paper presents changes made to a first-year Earth Sciences field course in the French Alps, where new GIS methods were introduced. Students use GIS in preparation to explore their research area using an elevation model and satellite images, formulate hypotheses and plan the fieldwork. During the fieldwork, a pilot group managed their field-observations using GIS and made digital maps. Students praise the use of quantitative digital maps in the preparation. Students made use of the available techniques during the fieldwork, although this could be further intensified. Some students were extra motivated due to the technical nature as well as the additional analytical possibilities. The use of GIS was experienced as a steep learning curve by students, and not all staff members are confident in supervising students using GIS, which calls for a sufficient preparation and training of both students and staff. The use of GIS adds abstract analyses and quantitative assessment, which is a complementary learning style to fieldwork that mostly focuses on practical skills.  相似文献   
55.
56.
This paper investigates the interplay between cultural traditions and policy effectiveness. It explores the differential impact of a large development program (Cassa per il Mezzogiorno), implemented for four decades, starting in the 1950s, to stimulate convergence between Italy's south and the more developed north, on municipalities with different histories. Namely, we consider a sample of municipalities located on either side of the historical border of the Kingdom of the Two Sicilies, whose legacy is considered, from Putnam onwards, to be a prime‐facie cause of Southern Italy's underdevelopment. Having been part of the Kingdom of the Two Sicilies is associated with a negative impact of development policies, but only when the allocation of development funds through the Cassa per il Mezzogiorno suffered from low quality of governance and was driven by political considerations rather than by efficiency ones.  相似文献   
57.
This paper measures the impact of wage zones—compulsory wage differentials at the province level—on Italy's local labor markets during the 1950s. Using spatial regression techniques, it finds that for the industrial sectors covered under wage zones there was an increase in employment when one crossed the border from a high‐wage province into a low‐wage one; the effect diminished, however, as the distance from the boundary increased. The paper also illustrates that the impact on the overall (nonfarm) private sector, which includes both covered and uncovered sectors, was negligible.  相似文献   
58.
We present experimental data examining the energetics and identification of axial bipolar reduction in contexts of lithic miniaturization on milky quartz. These experiments answer two specific questions. First, does bipolar reduction provide any benefits over freehand reduction? Second, can axial bipolar reduction be distinguished from freehand reduction? Our data show that bipolar reduction requires significantly less time to reduce a percentage unit of core mass and to produce a millimeter of cutting edge on milky quartz than freehand reduction. Milky quartz bipolar reduction surpasses even the cutting edge production efficiency of obsidian pressure blades. We outline a series of quantitative criteria for identifying bipolar cores and flakes. Our results show that bipolar cores and flakes can be distinguished from those produced using freehand reduction by quantifying platform crushing, distal flake rebound scars, bulb shearing, as well as axial, bipolar, and splintered flake terminations. Our results challenge the widely held perceptions about the wastefulness of bipolar reduction and provide clear guidelines for identifying this reduction strategy in archaeological milky quartz assemblages.  相似文献   
59.
This article analyses a collection of 26 watercolour drawings which portray ethnographic types from the Americas, Asia, and Africa. These drawings, presently kept at the British Library, were made for John Locke by his servant Sylvester Brounower during Locke’s exile in the Netherlands in the 1680s.  相似文献   
60.
This paper reports on the construction of a full‐scale Bronze Age‐type sewn‐plank boat based on the Ferriby boats. The boat, which was named Morgawr, was constructed in the National Maritime Museum Cornwall in Falmouth, England, during 2012 and the first months of 2013, as part of a larger exhibition in the museum. This paper provides the background and context of the project, describes the process of building the craft, and reflects in particular on differences between Morgawr and the ‘hypothetical reconstruction of a complete sewn‐plank boat’ published in 1990 by Ted Wright and John Coates which formed the basis for this project.  相似文献   
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