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81.
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   
82.
ABSTRACT

For most interpreters of the philosopher from Rotterdam, his political doctrine is solely a consequence of his religious and moral doctrines, and so an image of Bayle as a political philosopher is not usually presented. To my mind, however, only by analyzing his political doctrine can the extent of his religious proposal be understood. In this article, I intend to show that both the Baylean criticism of popular sovereignty and his rejection of the right of resistance are analyses that are indissociable from the Baylean doctrine of tolerance. The protection of individual freedom of conscience and the defense of a multi-confessional state model, tolerant regarding religious minorities, can only be articulated as historical reality if they rest on the political doctrine of indivisible sovereignty and on the strictest separation between political obedience and religious membership.  相似文献   
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85.
A polyphasic tectonic‐fluid system of a fault that involves crystalline and carbonate rocks (Hospital fault, Barcelona Plain) has been inferred from regional to thin section scale observations combined with geochemical analyses. Cathodoluminescence, microprobe analyses and stable isotopy in fracture‐related cements record the circulation of successive alternations of hydrothermal and low‐temperature meteoric fluids linked with three main regional tectonic events. The first event corresponds to the Mesozoic extension, which had two rifting stages, and it is characterized by the independent tectonic activity of two fault segments, namely southern and northern Hospital fault segments. During the Late Permian‐Middle Jurassic rifting, these segments controlled the thickness and distribution of the Triassic sediments. Also, dolomitization was produced in an early stage by Triassic seawater at shallow conditions. During increasing burial, formation of fractures and their dolomite‐related cements took place. Fault activity during the Middle Jurassic–Late Cretaceous rifting was localized in the southern segment, and it was characterized by hydrothermal brines, with temperatures over 180°C, which ascended through this fault segment precipitating quartz, chlorite, and calcite. The second event corresponds to the Paleogene compression (Chattian), which produced exhumation, folding and erosion, favouring the percolation of low‐temperature meteoric fluids which produced the calcitization of the dolostones and of the dolomite cements. The third event is linked with the Neogene extension, where three stages have been identified. During the syn‐rift stage, the southern segment of the Hospital fault grew by tip propagation. In the relay zone, hydrothermal brines with temperature around 140°C upflowed. During the late postrift, the Hospital fault acted as a unique segment and deformation occurred at shallow conditions and under a low‐temperature meteoric regime. Finally, and possibly during the Messinian compression, NW‐SE strike‐slip faults offset the Hospital fault to its current configuration.  相似文献   
86.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
87.
Jacobean devotion and national awareness are closely related in the Poema de Fernán González (PFG). The great advance of the Reconquest in the thirteenth century and the reevaluation of the past that it caused enabled the broad Hispanic perspective of the PFG. Spain is not only a distant and longed-for reality (“regnum Gothorum”) but a current political concept. This is the frame of the PFG's intense Castilian sentiment. Castile is the bastion of the Visigothic monarchy, which did not yield to the Muslims and was the foundation for the recovery of Spain. The territorial diversity becomes the outstanding feature of this country, in which the “Montaña” takes an important role. Confronting the proposal of the cult of Saint Millán by the Monastery of San Millán de la Cogolla, the author of the PFG, aware of the damages that such a cult was causing to his monastery, clings to the Jacobean devotion that achieved a broad Hispanic scope.  相似文献   
88.
Relying on stochastic frontier analysis we propose a methodology to study the technological characteristics and cost efficiency levels related to the provision of public infrastructure for basic utilities. The methodology assumes a cost minimizing behaviour on the part of public officials when planning the construction of local infrastructure, which is represented by way of a flexible translog cost function. Introducing relevant definitions of scale economies, associated with larger numbers of inhabitants and dwellings, as well as economies of density, brought about by reductions in urban dispersion, we analytically determine the optimal population densities for which average cost is minimized. We illustrate our model with the water cycle sector, including water distribution, sewage collection and cleansing of wastewater, and considering data at the municipality level for the Spanish region of Castilla y León. The obtained results indicate potential cost savings in the form of decreasing average costs, as relevant scale and density economies are present, along with large inefficiency levels. Relevant policy guidelines favouring larger and denser urban sizes are drawn, as the observed cost excess is the result of a general suboptimal urban size in terms of population density, and the negative effects of dispersed settlement patterns.  相似文献   
89.
The paper presents the analysis of organic and mineral sediments filling the depression, which developed over the landslide located at the slope (767–773 m a.s.l.) of Lubań ridge decscending to the Ochotnica river valley in the Polish Flysch Carpathians. The landslide formed in an early stage of the Subatlantic Phase (2490 ± 35 BP). The top of peat is dated at 1360 ± 50 years BP and is covered by 72 cm of clayey silts with some sandy intercalations, which indicate slopewash after deforestation. The pollen of ruderal plants and Cerealia (undiff.) reflect agricultural activity in the surroundings. The fragments of charcoal indicate the age of the forest clearance to the first half of the 17th century. The late forest clearance at the elevated north exposed slopes followed 200–300 years later in relation to the foundation of the village at the valley floor.  相似文献   
90.
Luis L M Aguiar 《对极》2006,38(3):440-461
Janitors in Canada increasingly suffer from what I call here “sweatshop citizenship”, which is a combination of disintegrating workplace rights and eroding social citizenship rights. This condition has been institutionalized by neoliberal state policies which have undermined the welfare state and the assumptions of citizenship which it embodied. Through an exploration of how sweatshop citizenship is being instituted in Ontario and British Columbia, I consider the difficulties which contemporary industrial practices in the cleaning industry and anti‐union legislation are presenting janitors, together with the possibility for their resisting such conditions.  相似文献   
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