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This paper is the last in a series presenting geochemical analyses of fragments of bituminous mixtures excavated from archaeological sites in Kuwait. The first was devoted to bituminous boat remains from the Ubaid‐related Neolithic site of H3, As‐Sabiyah, while the second dealt with bituminous amalgams from the Partho‐Sasanian site of cAkkaz, a former island now joined to the south side of Kuwait Bay. This, the third, refers to bitumen‐bearing samples from two other islands, Failaka and Umm an‐Namel, and covers a time span including the Early Dilmun period, the Kassite period and the Hellenistic to Early Islamic periods. The composition of the bituminous amalgams was studied in detail. The proportions of soluble and insoluble organic matter as well as vegetal organic matter were evaluated. Mineralogical composition by X‐Ray diffraction and thin‐section analysis was used to estimate the mineral input in the bituminous mixtures. It can be confirmed that the recipes used in the preparation of these bituminous amalgams comply with those traditionally used in antiquity, as seen at many sites in Mesopotamia and the Gulf. Analysis of the soluble organic matter, and especially its ‘‘saturates’’ fraction, provided sterane and terpane distributions and the measurement of diagnostic molecular ratios. These data, complemented by the isotopic composition of asphaltenes, allowed the identification of the sources of the bitumen, by calibration with numerous references from Iran and northern Iraq (oil seeps, bitumen from archaeological sites). It was established that the bitumen from Failaka and Umm an‐Namel was mainly imported from central Iraq (Hit‐Abu Jir) and northern Iraq (around Mosul). One sample of oil‐stained sand, dating to the Early Dilmun period, originated from Burgan and thus documents small‐scale imports from inland Kuwait. These results, and those of previous analyses, agree with the geopolitical context of the Early Dilmun, Kassite and Hellenistic periods, and the maritime trade routes that linked Mesopotamia to the settlements of the Gulf and beyond. The paper concludes with an overview of recent bitumen provenance analyses, and discerns chronological patterns in the distribution of Iraqi and Iranian bitumen in the Gulf and Indian Ocean, from the Neolithic to the Islamic periods.  相似文献   
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We study how the level of trade costs and the intensity of competition interact to explain the nature and intensity of trade within a given industry and the location of firms across countries. As trade costs decrease from very high to very low values, the global economy moves from autarky to two‐way trade, through one‐way trade from the larger to the smaller region. By exploring the intensive and extensive margins of exports, we investigate how the intensity of trade reacts to the degree of competitiveness. Furthermore, when firms are free to change location, they flow from the small to the large country, and the larger country is always a net exported on the manufactured good. Firms located in the big country have a bigger size than those located in the small one. Under one‐way trade, the relocation of firms changes their attitude toward export.  相似文献   
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ABSTRACT

Growing scientific literature evaluates the impact of traffic-calming devices in terms of mobility behavior and safety, but little is known about their perceived impact from the point of view of children. Our study asks children about their perceptions of different traffic-calming measures around their schools. It draws on data gathered through eight focus groups, followed by walking tours with Grade 6 children (11–12 years old) (n?=?65, 27 boys, 38 girls) from elementary schools in different urban contexts in Quebec, Canada. Qualitative analysis of the discussions shows that (a) vehicle speed is the main perceived threat for participant children; (b) children are confident about the effectiveness of self-enforcing traffic-calming devices that reshape the street geometry; and (c) they are skeptical about the effectiveness of ‘informative’ measures such as signs and lines (marked pavement). Our findings inform public policy for a more effective promotion of walking and cycling among children.  相似文献   
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Local topography is an important parameter determining the erection of a certain type of site on a certain location in the landscape. Despite the importance of topography in archaeological landscape research, the role of local topography has remained rather unexplored compared to other specific topographic parameters such as slope, aspect, curvature or visibility. Therefore, three methods to assess the relative topographic position of sites are applied and discussed here. The Bronze Age barrow dataset of northwest Belgium acts as the subject for this methodological case study. First, elevation percentile calculates the area that is lower than the central point within a predetermined neighborhood. Secondly, difference from mean elevation measures the relative topographic position of the central point as the difference between the elevation of this central point and the mean elevation within a predetermined neighborhood. And finally, deviation from mean elevation calculates the relative topographic position of the central point as the difference from mean elevation divided by the standard deviation of elevation, within a predetermined neighborhood. These three methods, each with their advantages and disadvantages, prove to be an added value for archaeological landscape research.  相似文献   
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ABSTRACT

This paper presents a comparison of the philosophical systems of Francesco Patrizi and Henry More. The point, however, is not to demonstrate Patrizi’s influence on More but rather to see how, with respect to some particular subjects, they both tried to offer a modern interpretation of Neoplatonism. The main axis of the analysis follows the topics of space, light, and soul. While to More, light is of merely marginal interest, it is demonstrated that space and soul are of crucial importance and play a similar role in both authors’ systems. They function as intermediary entities that link the higher and the lower reality and form a sort of canvas upon which the material world unfolds. Yet, in comparison with Patrizi, More’s system is both constrained by a much stricter, dualistic classification and at the same time veers dangerously close to immanentism and pantheism (which More tries to avoid).  相似文献   
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