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991.
The use of seashells for the decoration of pottery from the sixth millennium cal BC is well known in the western Mediterranean, with the emergence of so-called Cardial Pottery. Actually, the most discussed issue up until now has been the use of bivalves for impressed decoration. However, the experimental approach followed in the present study provides for the first time clear evidence for the utilization of a very specific group of shells as tools for the decoration of some of the early pottery productions in northwest Africa. In particular, we propose the use of cowry, a gastropod family with a well-known ideological and symbolic role in many human cultures around the world. Also, it is suggested that cowry was used for making impressed wares on the opposite European shore. The implications for reconstruction of Neolithic diffusion along both the European and African coasts of the Mediterranean are of great significance.  相似文献   
992.
State and institutional actors have been shaping settler‐farmer subjectivities in order to transform the landscape and thus the history and geography of the Canadian Prairies. This paper expands the application of environmentality from its origins in colonial forestry to interrogate agriculture on prairie landscapes. The Canadian state used the technologies of environmentality to influence “common sense” attitudes and behaviours, which acted to deterritorialize Indigenous communities and then manipulated their subjectivities to guarantee settler‐farmer access to land. Later, institutions and states moulded settler‐farmer subjectivities of correct farming behaviour in an effort to convert soil, water, and seeds into economic resources. These environmental objects, in turn, acted upon settler‐farmer subjects by setting biophysical and genetic limits such as soil fertility, water quality and quantity, and plant hardiness and disease resistance. Resisting environmentality requires understanding processes of subjugation while also creating counter‐narratives of “good” farming behaviour and Indigenous‐settler relations.  相似文献   
993.
994.
Preliminary functional results obtained from the quartzite assemblage of the Early Middle Palaeolithic site of Payre (South-eastern France) are presented. In an area rich in flint, hominins at Payre also collected quartzite in their local environment, specifically along the Rhône River banks. Although the Payre lithic assemblage is largely composed of flint, quartzite was introduced in the site mainly as large cutting tools knapped outside. This fact pointed out an apparently highly differential treatment of the raw material types available in the region. A major concern is to understand the reason why. Is there any functional reason for the introduction of those artefacts, perhaps to perform specific activities related to the toughness of quartzite? Or is there any functional differentiation among the various raw materials? Use-wear analysis is a useful tool for better understanding human technological choices and strategies of lithic raw material management. Before attempting to extensively apply use-wear analysis on the quartzite assemblage, we analysed a limited sample to evaluate the general surface preservation. A specific experimental programme with the same local quartzite was carried out in order to provide a reliable comparative reference for interpreting use-wear evidence on archaeological implements. Methodological difficulties related to use-wear analysis applied to quartzite artefacts are also discussed. Both Optical light microscopy (OLM) and Scanning Electron Microscopy (SEM) were employed in this study; however, interpretations were elaborated considering principally SEM micro-graphs.The analysis of the archaeological material showed a good state of preservation of the surfaces with a low incidence of post-depositional alterations. The documented use-wear allowed us to identify the active edges, the kinematics and, more rarely, the worked material. Chopping activities were documented on two large artefacts suggesting a specific utility of those tools.  相似文献   
995.
The composition and manufacture of Late Bronze Age metallic artefacts from funerary and domestic contexts of southern inland Portugal was studied. The prevailing trend comprises binary bronzes (10.3 ± 2.1 wt% Sn) showing deformed equiaxial grains, annealing twins and slip bands. The alloy composition is somewhat independent of artefact type, while the manufacture seems to rely on artefact function and the skilfulness of the metallurgist. The technological characteristics were linked with archaeological and chronological features, disclosing some artefacts of uncommon composition, such as low‐tin bronze bracelets (4.3–7.1 wt% Sn) associated with ornaments of exotic materials (glass and Egyptian faience beads, and also ostrich egg shell beads). The assemblage testifies to an archaic trade with the Mediterranean region before the establishment of the first Phoenician colonies on the southern Iberian coast.  相似文献   
996.
There is growing support amongst scientists worldwide about the need for a shift in river management approaches to include hydrogeomorphic processes. However, the degree to which these concepts are transferred to governmental agencies and practitioners varies widely. In Quebec, for example, many stream restoration projects are based on the (incorrect) assumption that river mobility and its inevitable consequences (bank erosion of meanders, presence of woody debris in the channel) are problematic for salmonids. This paper presents examples drawn from current guidelines on stream restoration for fish habitat in Quebec to demonstrate the need to improve the knowledge exchange among scientists and decision makers about the positive impact of river mobility and large wood dynamics on biodiversity. Our observations reveal that existing guidelines for stream restoration in Quebec need to be revised to better integrate hydrogeomorphic concepts and to no longer assume that maintaining rivers in a static state is beneficial for fish. Adopting the “freedom space for rivers” approach would likely result in improved habitat as it combines natural processes related to mobility, flooding, and riparian wetland connectivity to determine the minimal space around rivers where development should not be allowed, thus allowing river processes to be restored.  相似文献   
997.
The p‐regions is a mixed integer programming (MIP) model for the exhaustive clustering of a set of n geographic areas into p spatially contiguous regions while minimizing measures of intraregional heterogeneity. This is an NP‐hard problem that requires a constant research of strategies to increase the size of instances that can be solved using exact optimization techniques. In this article, we explore the benefits of an iterative process that begins by solving the relaxed version of the p‐regions that removes the constraints that guarantee the spatial contiguity of the regions. Then, additional constraints are incorporated iteratively to solve spatial discontinuities in the regions. In particular we explore the relationship between the level of spatial autocorrelation of the aggregation variable and the benefits obtained from this iterative process. The results show that high levels of spatial autocorrelation reduce computational times because the spatial patterns tend to create spatially contiguous regions. However, we found that the greatest benefits are obtained in two situations: (1) when ; and (2) when the parameter p is close to the number of clusters in the spatial pattern of the aggregation variable.  相似文献   
998.
We analyze whether efficiency wages operate in urban labor markets, within the framework proposed by Ross and Zenou, in which shirking at work and leisure are assumed to be substitutes. We use unique data from the American Time Use Survey (ATUS) that allow us to analyze the relationships between leisure, shirking, commuting, employment, and earnings. We confirm that shirking and leisure are substitutes, and present an estimate of this relationship, representing the only empirical test of the relationship between a worker's time endowment and shirking at work. Our findings point to the existence of efficiency wages in labor markets.  相似文献   
999.
Pigments appearing on ninth–twelfth-century AD-carved stucco, wall painting, and terracotta friezes excavated at Nishapur in north-eastern Iran were investigated by optical reflectance spectroscopy, micro X-ray fluorescence spectrometry (μ-XRF), X-ray diffractometry (XRD), micro-Raman spectroscopy (μ-Raman), and scanning electron microscopy (SEM). Many of the pigments identified including vermilion, red lead, hematite, limonite, carbon black, atacamite, calcite, and gypsum have been identified in previous studies of pigments used in later Islamic periods. However, a series of unusual pigments such as wulfenite, pyromorphite, phoenicochroite, and jarosite were also found in the present study. The association of kaolinite and alunite with limonite and other Fe-bearing yellow pigments points to a local provenance for these pigments. In addition, the presence of orpiment in the vermilion may be indicative that the vermilion was artificially manufactured. These findings suggest that pigment use and manufacturing during the ninth to eleventh centuries in Nishapur was still in a trial-and-error stage and the palette known from the twelfth century onwards had not yet been systematized.  相似文献   
1000.
Traditional taphonomic analyses do not consider the emergent properties resulting from the relationship of variables. Several of these emergent properties are expressed spatially. Here, we present a spatial taphonomic approach to the understanding of post-depositional processes affecting experimental assemblages modified by fluvial currents. Spatial statistical methods are a great tool to understand how different taphonomic variables relate at a spatial scale. The results of the application of this method to bone assemblages affected by low- and high-energy flows show the loss or modification of most of the original spatial taphonomic relationships. It also shows the degree of bone loss according to element, anatomical section and bone structure, and shape types. Anisotropy is identified in both experimental contexts. These results add new criteria to assess the impact of water flows in bone assemblages and contribute to define the properties of lag assemblages.  相似文献   
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