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111.
Until a few years ago North-West Africa was ignored in our hypothesis on the neolithization of Western Mediterranean. Moreover, the few excavations focused exclusively on the test of stratigraphies in order to obtain chronological sequences. Recently developed archaeological projects allowed the inclusion of this region in the scientific debate on the origin and evolution of its Neolithic, on the contacts with the Iberian Peninsula through the Strait of Gibraltar, as well as on the documentation of ways of live, habitation structures, and economic strategies. The open area excavation of Zafrín, in the Chafarinas Isles – an archipelago located a short distance from the North African coast – and the full analysis of its lithic industry (technology, typology and use-wear), here presented, represents a novelty on the Neolithic research in North Africa. This in turn will permit us to approach subsistence strategies and the way of life developed by the Neolithic communities of the region.  相似文献   
112.
The use of minimum number of individuals (MNI) in the analysis of mammal archaeofaunal assemblages has received intense criticism for its derived nature and its dependence of biasing variables. Some authors have argued that similar taxonomic variability as documented by MNI can be achieved with other less biased measuring units, such as number of identified specimens (NISP) and derivates thereof. The present study is the first experimentally controlled test that shows the degree of bias of estimates of MNI and NISP by different analysts. It shows that the margins of error of both measuring units are independent and that MNI can be more accurately estimated than NISP, despite its “derived” inferential nature.  相似文献   
113.
This paper examines the level and evolution of polarization in regional per capita income in the European Union between 1977 and 1999. In this analysis, non-parametric estimation techniques are combined with the calculation of various polarization measures. The results obtained suggest a decrease in regional polarization in the European context during the period analysed, as a consequence of various factors, at times working in opposite directions. The findings also reveal the existence of discrepancies between the evolution of polarization and regional inequality. Finally, the analysis carried out highlights the importance of the role played by the national component and the spatial dimension in the formation of homogeneous groups of regions linked by similar development levels in the distribution under study.  相似文献   
114.
This paper examines skeletal and ancient DNA evidence in the study of suspected tuberculosis infection in the late pre-Hispanic and Colonial-era Lambayeque Valley Complex, north coast Peru (A.D. 900–1750). We integrate information on macroscopic lesion characteristics and distribution, radiographic and CT scan imagery, and analysis of Mycobacterium tuberculosis complex rpoB and IS6110 ancient DNA (aDNA) sequences. Destructive lesions were observed in the vertebral bodies of three precontact indigenous adult males, one colonial adolescent female, and in the cranium of a Colonial-period subadult. Assessment of lesion morphology and distribution led us to consider multiple diseases, but tuberculosis represents the most likely diagnostic option in all individuals. DNA was poorly preserved in all samples, but an IS6110 sequence was amplified in one precontact individual consistent with macroscopic diagnosis. These findings expand the geographic and temporal extent of tuberculosis to the late pre-Hispanic and Colonial north coast of Peru to highlight potential synergisms between diet, settlement patterns, and the evolution of Andean tuberculosis before and after European conquest. Moreover, this study helps focus several key questions in Andean tuberculosis research, including possible reassessment of the presence of the IS6110 sequence in the pre-Columbian Americas. Methodological considerations include differential diagnosis – especially with incomplete skeletons – and limitations of aDNA studies underscoring an approach integrating macroscopic, radiographic, and molecular lines of evidence in the paleopathological investigation of one of humankind’s most devastating and destabilizing diseases.  相似文献   
115.
We report a collaborative maritime archaeological project in Uruguay, one of several Latin American countries where the subject is undergoing review in terms of the ways it is practised and managed. Uruguay is typical of many states where there has been a tension between a heritage-based approach in which the results of investigations are viewed as publicly owned, as opposed to the profit motive in which commercial and personal gain is the underlying ethic. This project was conceived both as a way of assisting the Uruguayan Heritage Commission in promoting the former approach as well as advancing a programme of research into the age of global exploration. This paper sets out the rationale of the initial field season and reflects on subsequent developments.  相似文献   
116.
A pollen diagram was prepared from Lake Almalou, a volcanic crater wetland located on the eastern flanks of the Sahand Volcanic Complex in NW Iran. The core provides a 3700-year record of human activity and environmental change in an upland region. We attempt to relate vegetation changes to both climatic change and historical events. Variations of anthropogenic pollen indicators suggest several phases of intensified human activities. Two strongly expressed agricultural phases are dated at about 2450–2220 cal BP (Achaemenid Empire) and 230–30 cal BP (collapse of Safavid Dynasty to the modern period). Historical rather than climatic events appear to be the main controlling factors for upland land-use dynamics. Fruticulture has been practiced in the region at least since the Iron Age, reaching its maximum importance 1500–1250 cal BP during the reign of Sassanid Empire; it declined by the time of Islamic conquest of Iran (651 AD). The Little Ice Age is tangibly recorded by higher lake water levels most probably due to both lower summer temperatures and higher annual precipitations. Low values of cereal-type and cultivated tree pollen during this period may indicate a change in the lifestyle from the cultivation of fields and orchards to a more nomadic life dominated by summer pasture. The modern period (1850 AD onwards) is characterized by expansion of agricultural activities to upland areas and intensified pastoralism.  相似文献   
117.
Cut mark frequencies in archaeological faunal assemblages are so variable that their use has recently created some skepticism. The present study analyses this variability using multivariate statistics on a set of 14 variables that involve differential skeletal element representation, fragmentation processes, carnivore ravaging impact, carcass size and tool type. All these variables affect the resulting cut mark frequencies reported in archaeological sites. A large sample of archaeofaunal assemblages has been used for this study. It was concluded that the best estimator of cut mark frequency in any given assemblage is the percentage of cut-marked long bone specimens (probably due to its better preservation than other anatomical areas), which is determined by fragmentation and carnivore ravaging. Carcass size and tool type also play a major role in differences in cut mark frequencies. Fragmentation is also a key variable determining the abundance of cut-marked specimens. It is argued that general cut mark percentages are of limited value, given the number of variables that determine them, and that a more heuristic approach involves quantifying cut marks in a qualitative manner.  相似文献   
118.
Stone masonry walls of ancient buildings have reasonable resistance to vertical loads but lower resistance to shear forces and reduced tensile strength. However, to achieve such compressive strength the masonry must not disaggregate when subjected to loading. This can be achieved if during the construction of the walls larger stones, usually referred as “through stones”, are used, spanning the thickness of the wall, making it possible to improve the transverse confinement of the masonry. For rehabilitation projects and structural reinforcement of such buildings, the transverse confinement can be achieved by fixing steel elements perpendicular to the wall. This confinement technique is often part of a more comprehensive rehabilitation solution, which includes the application of mortar or concrete reinforced layers applied to the wall surface.

This article presents results of an experimental research on material properties and mechanical characterisation of stone masonry specimens strengthened by two transverse confinement solutions (independent steel reinforcing rods and continuous steel ribbons wrapping the specimen). Specimens were tested under compression and compression and shear loadings.

This experimental work is part of a major research project to study the mechanical behavior of URM and strengthened walls, and the characteristics of the building materials of such specimens.  相似文献   

119.
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   
120.
The recent increase in business services in terms of both value added and employment has had a positive effect on regional economies, helping them to create a comparative advantage and contributing to the general development of regional productive systems. This heterogeneous set of activities is characterized, among others, by its uneven distribution in the territory. In this paper we aim to identify the key factors that influence the location of business services within the NUTS 2 regions of the European Union. Using a multivariate analytical approach (combining a principal components factor analysis and a multiple linear regression by means of ordinary least squares), four key factors have been identified. In terms of their influence on the location of business services, we can pinpoint the following factors: urban dimension, competitiveness, accessibility and economic dynamism. It was found that business services tend to locate in urban, densely populated and dynamic areas with high levels of competitiveness and easy access.  相似文献   
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