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941.
The approaches of comparative studies and profile measurements, often used in order to detect post‐depositional alterations of ceramics, have been applied simultaneously to two sets of Roman pottery, both of which include altered individuals. As analytical techniques, Neutron Activation Analysis and X‐Ray Diffraction have been used. Both approaches lead to substantially different results. This shows that they detect different levels of alteration and should complement each other rather than being used exclusively. For the special process of a glassy phase decomposition followed by a crystallization of the Na‐zeolite analcime, the results suggest that it changes high‐fired calcareous pottery rapidly, and so fundamentally that the results of various archaeometric techniques can be severely disturbed.  相似文献   
942.
The ability to make rapid measurements on small samples using laser fluorination enhances the potential of oxygen isotopes in the investigation of early inorganic materials and technologies. δ18O and 87Sr/86Sr values are presented for glass from two primary production sites, four secondary production sites and a consumer site in the Near East, dating from Late Antiquity to the medieval period. δ18O is in general slightly less effective than 87Sr/86Sr in discriminating between sources, as the spread of measured values from a single source is somewhat broader relative to the available range. However, while 87Sr/86Sr is derived predominantly from either the lime‐bearing fraction of the glass‐making sand or the plant ash used as a source of alkali, δ18O derives mainly from the silica. Thus the two measurements can provide complementary information. A comparison of δ18O for late Roman – Islamic glasses made on the coast of Syria–Palestine with those of previously analysed glasses from Roman Europe suggests that the European glasses are relatively enriched in 18O. This appears to contradict the view that most Roman glass was made using Levantine sand and possible interpretations are discussed.  相似文献   
943.
Ulúa marble vases from the Ulúa Valley of northwestern Honduras are a hallmark luxury good from Late Classic (ad 600–900) Mesoamerica. Archaeological and stylistic data point to centralized production at one site, Travesía. This paper analyses stable isotope and petrographic data from the vases and three potential procurement areas. The results indicate that the vases were produced from one primary source with one, potentially two, secondary sources. Procurement patterns most probably corresponded to contemporary communication routes. The results clearly indicate that a multi‐method approach is necessary for sourcing marble from Honduras.  相似文献   
944.
The Late Bronze Age (1550–1200 bc ) in the Near East was a period of cultural development, international trade and technological innovation, notably in metallurgy and silicate technology. As a spin‐off of the new glass technology, new colorants were also applied to faience glazes presumably to increase their aesthetic value. Here, we report on the presence of chromite minerals in the glaze of a faience vessel from Deir ‘Alla, Jordan, 1200 years earlier than reported so far. Importantly, chromite was not only used as a greyish pigment, but also as a nucleating agent for spherulitic crystallization of augite in the amorphous glaze. These synthetic augite formations give a unique, sparkly appearance to the faience vessel, apparently imitating a metallic look. The making of such an intricate glaze and its contemporary significance reflect not only the high level but also the appreciation of innovation in that region at that time.  相似文献   
945.
Achieving the Millennium Development Goal of halving poverty will require simultaneous action on two separate fronts: helping poor people escape from poverty, and stemming the flow of people into poverty. This article examines forty Peruvian communities, and finds that descents into poverty have occurred alongside escapes in every one of them. Escape and descent are asymmetric in terms of reasons: while one set of reasons is responsible for escapes from poverty, another and different set of reasons is associated with descent. Making progress in poverty reduction will require measures to accelerate escapes whilst at the same time slowing down descents. The article looks at the different policies which will be required to serve these two separate purposes.  相似文献   
946.
One of the defining objectives in location science is to maximize dispersion. Facilities can be dispersed for a wide variety of purposes, including attempts to optimize competitive market advantage, disperse negative impacts, and optimize security. With one exception, all of the extant dispersion models consider only one type of facility, and ignore problems where multiple types of facilities must be located. We provide examples where multiple-type dispersion is appropriate and based on this develop a general class of facility location problems that optimize multiple-type dispersion. This family of models expands on the previously formulated definitions of dispersion for single types of facilities, by allowing the interactions among different types of facilities to determine the extent to which they will be spatially dispersed. We provide a set of integer-linear programming formulations for the principal models of this class and suggest a methodology for intelligent constraint elimination. We also present results of solving a range of multiple-type dispersion problems optimally and demonstrate that only the smallest versions of such problems can be solved in a reasonable amount of computer time using general-purpose optimization software. We conclude that the family of multiple-type dispersion models provides a more comprehensive, flexible, and realistic framework for locating facilities where weighted distances should be maximized, when compared with the special case of locating only a single type of facility.  相似文献   
947.
948.
This article investigates attempts to portray Jesus as a “manly Man” for “manly men” in the wake of World War One. The Jesus that emerged as a result of this enterprise was a heroic personality formed through interplay between ideals about soldiers and Christ. Whilst only some military virtues were valued — and only in particular forms — even these proved problematic in certain respects. In particular, attempts to integrate soldierly and moral manliness, especially through resurgent use of notions like chivalry and crusade, failed to connect with soldiers’ actual experiences. Nonetheless, the manly Jesus represented an important religious response to World War One. It illuminated much about New Zealand religion and religious interaction with visions of ideal manhood. In particular, visions of a manly Jesus highlighted that ideals of moral and domestic manhood and more assertive ones coexisted in a state of tension.  相似文献   
949.
ABSTRACT We investigate how cross‐country differences in firms' fixed set‐up costs affect the trade‐off between global efficiency and spatial equity. Our analysis reveals that the standard assumption of symmetry in set‐up costs masks the existence of an interesting effect: the range of available varieties depends on the spatial distribution of firms. In such a setting, where the market outcome leads to excessive agglomeration in the symmetric case, a planner may opt for asymmetric set‐up costs and even more agglomeration. We show that the planner will always favor lower set‐up costs in the large country with more agglomeration when the consumer's marginal preference for variety is high, or with less agglomeration when the consumer's marginal preference for variety is low.  相似文献   
950.
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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