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111.
The Framework Convention on Climate Change addressing the problem of global warming at the international level, was signed in 1992. A protocol to the convention, including emission limitation or reduction commitments, was recently adopted. Joint implementation (JI), in any of its various forms, constitutes one of the mechanisms for reducing overall greenhouse gas emissions. The basic rationale for JI is to achieve the greatest global environmental benefits for the least cost. JI can in principle be a useful instrument in implementing environmental agreements. In this article, the authors argue that JI raises several issues of concern in relation to the realization of different aspects of sustainable development. More specifically, in the forestry sector, JI often seems to conflict with local and global environmental priorities. Moreover, the basic premiss on which JI forestry projects are predicated, namely the carbon sequestration potential, is not borne out by available scientific date. In the long term, such projects have a very limited capacity for carbon sequestration considering that woody biomass eventually decays or burns.  相似文献   
112.
In early Roman times, iron was likely supplied to the city of Sagalassos through the smelting of close-by hematite ores. In the early Byzantine period, magnetite–titanite placer sands in some instances could have been exploited for its iron. For the intermediate late Roman period, however, the source of the locally used iron was unknown. Pb and Sr isotopic analyses of iron ores from the area of Camoluk, just south of the territory of Sagalassos, and of late Roman iron artefacts from the antique city itself, reveal a very close resemblance. This makes the use of the Camoluk ores to supply Sagalassos with raw iron in the late Roman period likely. It is also shown that combined Pb and Sr isotopic analyses provides a powerful tool to distinguish chronological groups of iron provenance and a technique that can determine the nature and source of iron raw materials used.  相似文献   
113.
Ancient mosaic tesserae are a range of materials of very varied and complex nature, including pottery, stone and glass. Raman spectroscopy is a powerful tool for the analysis of all these kinds of materials. In the particular case of glasses, this technique can be used both for a study of surface weathering and for the characterization of bulk structure, but it has not yet been extensively used for the characterization of mosaic glass tesserae. We carried out Raman analyses on a set of Roman and Late Antiquity period mosaic glass samples, which allowed a good characterization of both the glass matrix and the crystalline inclusions. All the samples show the typical Raman signatures of soda-lime-silicate glasses. Several crystalline phases were also identified, being relics of raw materials used during the glass manufacturing process, such as quartz and feldspars, or linked to the glass color/opacification, such as bindheimite and cuprite. The analyses also led to the identification in some blue, turquoise and green tesserae of calcium antimonate, whose Raman signature has only recently been recognized in the scientific literature on mosaic glasses. Some emphasis is given to the analysis of red lead-containing tesserae, colored with Cu+ ions or even Cu0 (or Au0) metal nanoparticles. Samples with peculiar compositions, as well as “modern” (and restoration) samples, could quite easily be distinguished from the ancient ones by their Raman spectra.  相似文献   
114.
A new methodology based on major and trace element analyses of slag inclusions is proposed to determine (or exclude) the provenance of iron artefacts. It is applied to verify if the Pays de Bray, a French area between Rouen and Beauvais, could have been an important supplier for the ferrous reinforcements used in the Middle Ages for the building of churches and cathedrals in these two towns. To this purpose, the behaviour of trace elements during both direct and indirect operating chains is studied combining experimental smelting and different analytical methods, such as SEM–EDS, ICP–MS, LA–ICP–MS and INAA, performed on archaeological samples. The chemical signature of the Pays de Bray iron ore and slag is determined considering MnO and P2O5 contents as a first rough filter and seven couples of trace elements. Then, the major and trace elements are analysed using the same methods in the slag inclusions of 32 artefacts from the Beauvais and Rouen churches, made by the bloomery process. The trace element signature of the inclusions from each artefact is compared with the ore from the Pays de Bray area. The iron used in the Rouen and Beauvais churches seems not to come mainly from the Pays de Bray.  相似文献   
115.
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   
116.
This paper aims to propose a data treatment method in order to efficiently exploit the major element compositional analyses made on slag inclusions (SI) of ferrous archaeological artefacts. This method is employed to study the reinforcements used in medieval monuments. The first part of the paper shows: (i) that SI composition can be very variable in an artefact and that it is necessary to analyse a sufficiently redundant number of inclusions; and (ii) that on the one hand a local concentration effect and, on the other hand additives during forging can cause this variability. Nevertheless, after filtering this data, it is showed that specific compounds (called here Non-Reduced Compounds – NRC) have in most of cases a constant ratio in the SI. This allows to evidence the signature of the system (ore, charcoal and pollutant) that produced the ferrous alloys. Moreover, a weighted average compound can be extracted from the results. It is demonstrated that, considering some specific elements with a different behaviour in the direct and indirect processes, it is possible to differentiate the two processes. A methodology is then proposed and applied to several samples gathered on different French medieval buildings to follow the diffusion of the indirect process in France.  相似文献   
117.
How do individuals assess the credibility of experts in various policy domains? Under what conditions does the public interpret particular scientific knowledge claims as being trustworthy and credible? Using data collected from an online survey experiment, administered to 1,507 adult residents of Quebec, this paper seeks answers to these questions. Specifically, we examine variation in the way members of the public perceive the credibility of scientific experts in the areas of climate change, shale gas extraction, cell phones, and wind farms. Our results contribute to the existing literatures on public perceptions of policy experts, framing, and cultural theory. We find that individuals evaluate expert credibility based on the way in which experts frame issues, and on the congruity/dissonance between these expert communication frames and one's underlying worldview. However, we also identify limits to these framing effects. Our findings shed light on the interaction of framing and political worldviews in shaping public perceptions of expert credibility in various policymaking contexts.  相似文献   
118.
A 15–18 months old child mummy, presently housed in Turin's Museum of Anthropology, was discovered in Gebelein (Upper Egypt) during excavations carried out by the Missione Archeologica Italiana, most likely in 1914.  相似文献   
119.
The question of access to drugs in developing countries is at present largely influenced by the TRIPS Agreement. TRIPS compliance in the field of health requires substantial changes to existing patent laws in some countries. These changes must be analysed in the context of the spread of epidemics like HIV/AIDS and in relation to other international obligations that states have, for instance, with regard to the human right to health.
Intellectual property rights treaties today have significant impacts on the realization of some human rights like the right to health. This article examines the extent to which TRIPS encompasses flexibility for developing countries to be able to foster better access to medicines. It also examines these issues from the point of view of human rights and considers, in particular, the ways in which the relationship between human rights and intellectual property can be improved in international law.  相似文献   
120.
Coprolite pollen analysis is increasingly used by palynologists to reconstruct the palaeovegetation especially in the arid to semi-arid regions where lakes and peat bogs are scarce. This study is the first palynological analysis of coprolites in Iran to examine their potential in palaeoenvironmental reconstructions. Four pollen-rich coprolite samples were studied from the Wezmeh Cave in western Iran with a recently discovered late Quaternary (70 ka to sub-recent) faunal assemblage dominated by carnivore remains. Pollen analysis of coprolites shows that a mountain steppe dominated the glacial landscapes of the area. Only one sub-recent sample indicates the presence of dispersed tree stands. One sample was rich in Tulipa pollen suggesting that tulips were relatively abundant during the glacial periods. Cousinia (Asteraceae) pollen was found in all samples with considerable values in one sample indicating its importance in the glacial landscapes of the Zagros Mountains. This study revealed that coprolite pollen analysis can provide an invaluable source of information to understand the floristic composition of palaeolandscapes of the Irano-Turanian region.  相似文献   
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