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Sawankhalok, located in north central Thailand, was an early stoneware ceramic production site where the first kilns were dug cave-like into the natural ground, a method used in China for thousands of years. After a century or so, kilns at Sawankhalok began to be constructed of brick. It is suggested that if the bricks were pre-fired then an external influence may have been responsible. To the contrary, if raw unfired clay was used in the construction of the kilns the evolution was more likely a consequence of conceptual continuity.With the aid of chemical and mineralogical analyses it is shown that the kiln bricks were unfired at the time of kiln construction thereby suggesting that traditional conservatism, apparent in many aspects of the industry, caused processes to remain unaltered in the absence of a persuasive reason for change. These conclusions reflect on the degree of indigenous technology and artistic development associated with Sawankhalok ceramics as opposed to external influence.  相似文献   
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Metalliferous (Fe–Cu–Pb–Zn) quartz–carbonate–sulphide veins cut greenschist to epidote–amphibolite facies metamorphic rocks of the Dalradian, SW Scottish Highlands, with NE–SW to NW–SE trends, approximately parallel or perpendicular to regional structures. Early quartz was followed by pyrite, chalcopyrite, sphalerite, galena, barite, late dolomite–ankerite and clays. Both quartz–sulphide and carbonate vein mineralisation is associated with brecciation, indicating rapid release of fluid overpressure and hydraulic fracturing. Two distinct mineralising fluids were identified from fluid inclusion and stable isotope studies. High temperature (>350°C) quartz‐precipitating fluids were moderately saline (4.0–12.7 wt.% NaCl equivalent) with low (approximately 0.05). Quartz δ18O (+11.7 to +16.5‰) and sulphide δ34S (?13.6 to ?1.1‰) indicate isotopic equilibrium with host metasediments (rock buffering) and a local metasedimentary source of sulphur. Later, low‐temperature (TH = 120–200°C) fluids, probably associated with secondary carbonate, barite and clay formation, were also moderately saline (3.8–9.1 wt.% NaCl equivalent), but were strongly enriched in 18O relative to host Dalradian lithologies, as indicated by secondary dolomite–ankerite (δ18O = +17.0 to +29.0‰, δ13C = ?1.0 to ?3.0‰). Compositions of carbonate–forming fluids were externally buffered. The veins record the fluid–rock interaction history of metamorphic host rocks during cooling, uplift and later extension. Early vein quartz precipitated under retrograde greenschist facies conditions from fluids probably derived by syn‐metamorphic dehydration of deeper, higher‐grade rocks during uplift and cooling of the Caledonian metamorphic complex. Veins are similar to those of mesothermal veins in younger Phanerozoic metamorphic belts, but are rare in the Scottish Dalradian. Early quartz veins were reactivated by deep penetration of low‐temperature basin fluids that precipitated carbonate and clays in veins and adjacent Dalradian metasediments throughout the SW Highlands, probably in the Permo‐Carboniferous. This event is consistent with paragenetically ambiguous barite with δ34S characteristic of late Palaeozoic basinal brines.  相似文献   
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The link between economic conditions and election outcomes is a pillar of social science. Voters prefer ‘better times’ to worse and reward or punish incumbents accordingly. We investigate the extent to which this truism holds in the Australian context, with particular emphasis on the 1993 result. While Australian election outcomes are generally not well predicted by prevailing economic conditions, we are impressed by the extent to which the 1993 election outcome is at odds with the state of the economy. In particular, we find Labor performed up to five percentage points better than expected in 1993, making this result one of the most exceptional election results ever observed in Australia. The sizeable electoral penalty typically accompanying large increases in unemployment was effectively nullified in 1993. We accurately predict the 1993 result (ex post) only if unemployment is considered electorally irrelevant. We conclude by suggesting a research agenda for better understanding the link between economic context and election outcomes in the Australian setting.  相似文献   
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In the examination of over 1300 burials from medieval Canterbury, one individual displayed a well-defined paracondylar process. Four other adults and two children presented with small tubercles at the same site. The aetiology of the trait is discussed with reference to cranial base variants and the so-called manifestation of an occipital vertebra.  相似文献   
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