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1.
One of the main factors involved in entheseal changes (EC) aetiology may be related to the physiological limits of biomechanical loading fixed during bone development, such that higher load during childhood and the adolescent growth spurt leads to a lower frequency of EC during adulthood. In this sense, it is possible that ECs may be related to overloading beyond an individual's normal physiological limits as established during childhood and adolescence. This meta‐analysis tested this aetiological possibility by studying the influence of terrain on the entheses of the lower extremities. The hypothesis is that individuals who inhabited rugged terrain have lower EC than those living in flat terrain. This is because biomechanical loads associated with rugged terrain will lead to a higher normal capacity (defined during skeletal development) mitigating the probability of overloading compared to those living in flat terrain who will therefore have a higher frequency of ECs. To test this, papers reporting EC frequencies in the lower limbs were analysed alongside the local terrain. Terrain was defined into two categories: flat or rugged based on altimetry profile, i.e. the average elevation gains and losses along four specific paths (North‐South, East‐West, Northwest‐Southeast, Southwest‐Northeast). Odds ratios were calculated to compare rugged and flat terrain. The overall results are consistent with the hypothesis that overloading is a factor in EC aetiology. However, when the analysis is conducted by sex and side, this general trend does not always occur. Limitations such as the lack of standardized age ranges could be affecting the outcome, i.e. older individuals have a higher frequency of ECs. The findings of this analysis suggest that the theoretical assumptions associated with the cause of ECs require further testing and evaluation. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
2.
马明 《江汉考古》2020,(1):55-64
本文通过对《藤花落》报告的层位学、类型学分析,将藤花落城址相关的遗存分为四期,并在此基础上对藤花落城址进行了研究,认为该城址的城墙上和壕沟内的柱洞属于栅栏遗留,栅栏是与城墙、城壕等一体的防御设施;藤花落龙山文化遗存属尧王城类型,晚期文化面貌发生改变与王油坊类型龙山文化的东传有关。  相似文献   
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A polyphasic tectonic‐fluid system of a fault that involves crystalline and carbonate rocks (Hospital fault, Barcelona Plain) has been inferred from regional to thin section scale observations combined with geochemical analyses. Cathodoluminescence, microprobe analyses and stable isotopy in fracture‐related cements record the circulation of successive alternations of hydrothermal and low‐temperature meteoric fluids linked with three main regional tectonic events. The first event corresponds to the Mesozoic extension, which had two rifting stages, and it is characterized by the independent tectonic activity of two fault segments, namely southern and northern Hospital fault segments. During the Late Permian‐Middle Jurassic rifting, these segments controlled the thickness and distribution of the Triassic sediments. Also, dolomitization was produced in an early stage by Triassic seawater at shallow conditions. During increasing burial, formation of fractures and their dolomite‐related cements took place. Fault activity during the Middle Jurassic–Late Cretaceous rifting was localized in the southern segment, and it was characterized by hydrothermal brines, with temperatures over 180°C, which ascended through this fault segment precipitating quartz, chlorite, and calcite. The second event corresponds to the Paleogene compression (Chattian), which produced exhumation, folding and erosion, favouring the percolation of low‐temperature meteoric fluids which produced the calcitization of the dolostones and of the dolomite cements. The third event is linked with the Neogene extension, where three stages have been identified. During the syn‐rift stage, the southern segment of the Hospital fault grew by tip propagation. In the relay zone, hydrothermal brines with temperature around 140°C upflowed. During the late postrift, the Hospital fault acted as a unique segment and deformation occurred at shallow conditions and under a low‐temperature meteoric regime. Finally, and possibly during the Messinian compression, NW‐SE strike‐slip faults offset the Hospital fault to its current configuration.  相似文献   
5.
High tourism growth in single-asset tourism cities is often associated with a standardization of supply of products and services by tourism entrepreneurs. However, and in contrast to this common-sense view, tourism growth in specific urban tourism milieus in the ‘sun-sea-sand’ tourism city of Antalya has stimulated tourism entrepreneurs to differentiate their products. Contrary to most economic-geography literature on spatial clusters, evolutionary economic geographers argue that inter-industry relations of (un)related variety are crucial in inter-firm differentiation. The aim of the paper is to define the factors that influence tourism-firm differentiation in the single-asset tourism city of Antalya. The empirical research is theoretically informed by evolutionary economic-geography literature, and pays much attention to the role different urban sub-milieus play in tourism-firm differentiation. It is the first research on the relation between (un)related variety and tourism-firm differentiation in tourism studies. The empirical research is based on primary data collected by a firm-level survey (hotels, restaurants, jewellery- and retail-trade firms) in the city of Antalya. The factors that influence tourism-firm differentiation are explored by using quantitative methods of analysis (an econometric logit-regression model and a correspondence analysis). The main result of the empirical research is that investments in firms in related sectors, in our case jewellery companies and hotels, are positively and significantly related to tourism-firm differentiation. In addition, the location tourism firms in areas visited by a mix of consumers (tourists and locals) also is positively and significantly related to inter-firm differentiation whereas urban milieus visited by locals only have a negative effect.  相似文献   
6.
李庚 《人文地理》2012,26(1):102-106
以西安市长安区、渭南市澄城县、宝鸡市岐山县为考察点,采用问卷调查法和SPSS软件对三县土地流转现状进行实证分析,以查明不同区域土地流转差异情况和造成土地流转差异的影响因素。结果表明,由于经济发展水平不同,三县区土地流转达成比例相差较大,流转规模、流转方式有很大不同,流转价格更是有较大差别,经济发达地区有较强的土地"非粮化"现象,土地流转更接近市场行为。非农收入水平、农户的受教育程度、各类土地流转中介和管理机构的完善程度、农户的社会保障程度等对土地流转有显著影响,且影响方式均为正向,并且对流出率的影响超过对流入率的影响。  相似文献   
7.
This study assesses the overall spatial variations and neighbourhood‐level “hot spots” of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra‐class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2–3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual‐level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community‐oriented health interventions may be required to reduce observed local health impacts.  相似文献   
8.
The role of the past in prehistoric societies is a frequently occurring topic in recent archaeological literature. It is proposed that prehistoric societies were concerned with the construction of an ancient past, and that relics were actively used as mnemonic devices in recalling the past. This paper comments on the significance of historicity in cultural reproduction on the basis of indigenous Sami conceptions of time and ancestry. It is a personal reflection from an archaeologist's point of view. The indigenous Sami concept of time, life and death implies that distances in the past were not ascribed any significant value and that there was no chronological or genealogical scale against which events in the past were measured. It is argued that relics were not ascribed a discursive value, and that they were not used as mnemonic devices in recalling an ancient past. By the example of Sami conceptions of time and ancestry, the author advocates great caution in promoting relics as carriers of collective memories in ancient societies.  相似文献   
9.
Tirana, the Balkan capital examined in this study, displays patterns of gendered job search behavior and access, which are unique within contemporary Europe and even within post-socialist Central and Eastern Europe. Here, it is a rather spatially constricted job search range rather than transport poverty that prevents women living in first-ring suburbs from attaining satisfactory employment. Female commutes are extraordinarily short and most often on foot. While the city now has nearly one million inhabitants and a high car ownership rate, and is located in Europe, the employment and mobility choices and behaviors of its female residents resemble those in developing rather than developed countries, and in small rather than large cities. The reasons underpinning this situation have more to do with socio-cultural gender barriers and less with transport poverty or labor market weaknesses. This finding might apply to other Balkan capitals or cities outside Europe, which have recently experienced large waves of internal migration and where both existing residents and newcomers have not yet adjusted to ‘big city’ life.  相似文献   
10.
80年代以来,我国学术界对原子弹轰炸及其相关问题的研究呈现出十分活跃的局面,并取得了可喜的成果。研究主要集中在美国使用原子弹的原因和动机、原子弹轰炸的历史作用、原子弹轰炸的后果和影响、原子弹轰炸的正当性问题以及关于日本败降的决定因素等问题上。  相似文献   
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