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Developmental enamel defects (DDE) are often used as indicators of general health in past archaeological populations. DDE include three common types of lesions: hypoplasia, diffuse, and demarcated opacities. Molar incisor hypomineralisation (MIH) was defined in 2001 as a qualitative enamel defect affecting first permanent molars and often permanent incisors. The European Academy of Paediatric Dentistry established criteria to diagnose MIH in current populations as demarcated white or yellow‐brown opacities of enamel with or without posteruptive breakdown. MIH is prevalent in current populations (average 14.2%) and may cause important damage to first permanent molars. Aetiological factors are uncertain. The discovery of MIH in archaeological skeletal collections based on macroscopic examination has been reported previously, in particular by Ogden and colleagues (2008). If MIH exists in past populations, there are profound implications regarding current aetiological hypotheses. Aims of the present study were to (a) reassess the London postmedieval archaeological collection from which the first cases of MIH were reported and evaluate the reliability of MIH diagnosis criteria in past populations and (b) differentially diagnose developmental defects of enamel and post mortem discoloration in the teeth. Contrary to the reported prevalence in the original study (93.2%), among 47 subadult (>18 years) individuals, a low MIH prevalence was determined (27%). Reliability of MIH diagnosis was tested with three MIH experts who were also physical anthropologists. Our study highlighted that the reliability of a macroscopic diagnosis of MIH in past populations is fair (Cohen's kappa = 0.35 ± 0.11; Fleiss's kappa = 0.3). It could explain the large differential in prevalence values in studies performed in archaeological collections. Pathological and taphonomic agents can produce enamel modifications indistinguishable from one another, even to an “experienced eye.” Here, we examined the literature to highlight potential differential diagnoses of MIH (taphonomic discoloration, amelogenesis imperfecta, fluorosis, rachitic teeth, etc.). Employing nondestructive analyses to characterise and diagnose tooth discoloration in past populations is highly recommended.  相似文献   
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While the links between contaminated sites and adverse effects on human health and well‐being are being increasingly recognised, some argue that the magnitude of the health problem is inadequately addressed because it is largely invisible. Health geographies literature has sought to highlight this invisibility by focusing on the link between contaminated sites and health. This study adds to health geographies by presenting unique insights into the geography of residents' worry about the disruptive effect of environmental contamination on health and well‐being. It analyses a sample of residents (n = 485) living near 13 contaminated sites across Australia. Ordinal logistic regression analysis of closed‐format survey questions was combined with coding of open‐ended survey questions to reveal the geography of residents' worry about contamination from nearby sites. First, the study explores some of the main relationships between residents, their environs, and contaminants from nearby source sites, which determines their levels of worry: residents' demographics, residents' proximity to sites, contaminant boundaries and borders, and type of contaminant. Second, the study investigates how worry affects residents' health and well‐being, ranging from effects on their personal functioning through to their sense of ontological security, which depends in part upon their perceptions of contaminants' impacts. Despite having identified a range of diverse and negative effects of worry about contamination on residents, we found that worry for contamination can also prompt coping strategies and problem‐solving, reinforcing the need for more research on this subject.  相似文献   
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From 1940 to 1960 across 20 large U.S. cities, rental housing's price fell, renters’ incomes rose, rent's share in household budgets fell, and, as expected, renters’ real housing consumption increased. From 1970 to 2010, rental housing's price increased, renters’ incomes decreased, but, unexpectedly, renters’ real housing consumption increased. We find neither demographics nor housing supply factors account for the anomalous post‐1970 increase in renters’ housing consumption. We conclude that after 1970 there was a nationwide increase in renters’ preferences for housing consumption. With incomes falling, renters increased housing consumption by decreasing consumption of other necessities including food, clothing, and transportation.  相似文献   
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Henry David Thoreau’s Yankee in Canada is easily overlooked. Because it is so selective in its depiction of life in the St. Lawrence River valley, historians of mid-nineteenth-century Canada have shown little interest in Thoreau’s first-hand account. To American readers, it offers little of the characteristic Thoreau found in Walden and Resistance to Civil Government. Yet, it is highly significant as an expression of national self-definition. Thoreau borrowed themes at least as old as the American Revolution when noting the pernicious rule of Catholic and British power in Canada. He set out to expose the promise of republican values by emphasizing the contrast between these and the poor and morally stunted life under Old World institutions. His work must therefore be interpreted as a call to his audience to commit more deeply than ever to the ideals that animated the Great Republic’s founding moment. It must also stand as a civic interpretation of American nationality at a time when this perspective was waning. Before long, Old World peoples would be racialized and the ideological embrace of the republican values advanced by Thoreau would no longer suffice in making American citizens.  相似文献   
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Edmond Halley made two scientific voyages in the Atlantic Ocean as captain of the HMS Paramore between 1698 and 1700. Following these voyages he published the first map showing lines of equal magnetic declination in 1701. Halley did not reveal how he constructed the map, however, and it remains unknown. In this study, a construction procedure is hypothesized that uses mathematical tools that were available in his day, namely arithmetical averages and Isaac Newton’s method of divided difference for fitting a polynomial curve to data. To enable his map construction, a method is suggested whereby Halley could have created new data to augment the situations where insufficient data were collected.  相似文献   
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Architectural reconstructions of plankhouses are central to the study of household and community organization on the Northwest Coast of North America. However, the sample of substantially excavated houses is constrained by their size, stratigraphic complexity, and typically limited surface expression. We present the results of a magnetic gradiometry survey of the Dionisio Point site (DgRv-003) village, occupied ca. a.d. 500–700 on the coast of British Columbia, Canada. Survey of four house platforms reveals patterning of magnetic anomalies consistent with the structure of shed-roof houses, a design recorded ethnographically and identified archaeologically at the site. These results suggest a consistent pattern of spatial and, potentially, social organization of the households. The similarity of patterns suggests that magnetometry may be useful for guiding plankhouse excavations elsewhere on the Northwest Coast, providing a means for expanding our knowledge of houses without relying solely on traditional excavation methods.  相似文献   
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