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31.
Human transport of bones with high food values, and destruction of bones with low density values are the traditionally invoked explanations of the frequencies of bones in archeological contexts. The manner in which these two explanations have been used suggests archaeologists assume the explanations to be independent of one another. The transport explanation is operationalized as the modified general utility index (MGUI) of Binford, and the destruction explanation is operationalized with measures of bone density. Statistical correlation of the MGUI with bone density, while weak, indicates that many high utility bones have low density values while many low utility bones have high density values. Because low density bones tend to be destroyed more readily than high density bones, inferences of human utility strategies derived from bone frequencies and based on the MGUI may be inaccurate. The utility strategies suggested by three archaeofaunas are compared to bone density, and two of these faunas are shown to potentially be the result of differential destruction and not human transport as measured by the MGUI.  相似文献   
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Teaching of critical spatial thinking in higher education empowers graduates to effectively engage with spatial data. Geographic information systems (GIS) and science are taught to undergraduates across many disciplines; we evaluate how this contributes to critical spatial thinking. The discipline of GIS covers the whole process of spatial decision-making, but GIS modules often ignore the context setting of spatial problems, and just cover the technical aspects of how to use GIS software. We outline how some existing GIS practicals could be improved to focus on the development of critical spatial thinking skills, competences and abilities that are valuable to graduates.  相似文献   
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Recognition and respect for sexual minorities in Hong Kong is still a contested area. Public sexual identity politics in Hong Kong has been framed by traditional Chinese gender ideology and imported Christian beliefs which are profoundly negative. Focusing on the interpersonal relationships in three spheres of life, the research adopted the sociological perspective of personal life and the feminist geographers’ idea of spatialization of identity management to analyze how the sexual self of sexual minorities has been marginalized and excluded in intimate social spaces of family, church communities and schools in Hong Kong with specific spatial practices and different forms of power/knowledge. By examining overlooked intimate injustice in personal life, this study illustrates that identity conflicts between Christianity and non-heterosexuality in everyday life is constructed through misrepresentation, misrecognition, harassment and exclusion in intimate relationships. Different types of knowledge are being used to reiterate pre-existing norms and institutionalized patterns of cultural value that constitute the sexual minorities as comparatively unworthy of respect. These micro-political processes involve both conformity and resistance to gender and sexual stereotypes. Participants managed to develop spatial coping strategies such as concealment, compartmentalization, confrontation and alternative sources of support to manage their lives with dignity and self-esteem.  相似文献   
34.
    
F. Wendler  A. Okamoto  P. Blum 《Geofluids》2016,16(2):211-230
Mineral precipitation in an open fracture plays a crucial role in the evolution of fracture permeability in rocks, and the microstructural development and precipitation rates are closely linked to fluid composition, the kind of host rock as well as temperature and pressure. In this study, we develop a continuum thermodynamic model to understand polycrystalline growth of quartz aggregates from the rock surface. The adapted multiphase‐field model takes into consideration both the absolute growth rate as a function of the driving force of the reaction (free energy differences between solid and liquid phases), and the equilibrium crystal shape (Wulff shape). In addition, we realize the anisotropic shape of the quartz crystal by introducing relative growth rates of the facets. The missing parameters of the model, including surface energy and relative growth rates, are determined by detailed analysis of the crystal shapes and crystallographic orientation of polycrystalline quartz aggregates in veins synthesized in previous hydrothermal experiments. The growth simulations were carried out for a single crystal and for grain aggregates from a rock surface. The single crystal simulation reveals the importance of crystal facetting on the growth rate; for example, growth velocity in the c‐axis direction drops by a factor of ~9 when the faceting is complete. The textures produced by the polycrystal simulations are similar to those observed in the hydrothermal experiments, including the number of surviving grains and crystallographic preferred orientations as a function of the distance from the rock wall. Our model and the methods to define its parameters provide a basis for further investigation of fracture sealing under varying conditions.  相似文献   
35.
    
We used hydrologic models to explore the potential linkages between oil‐field brine reinjection and increases in earthquake frequency (up to Md 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>Md 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios including assigning an effective or bulk permeability value to the crystalline basement, including a conductive fault zone surrounded by tighter crystalline basement rocks, and allowing permeability to decay with depth. We initially adopted a 7 m (0.07 MPa) head increase as the threshold for triggered seismicity. Only two scenarios produced excess heads of 7m five years after peak injection. In the first, a hydraulic diffusivity of 0.1 m2 s?1 was assigned to the crystalline basement. In the second, a hydraulic diffusivity of 0.3 m2 s?1 was assigned to a conductive fault zone. If we had considered a wider range of threshold excess heads to be between 1 and 60 m, then the range of acceptable hydraulic diffusivities would have increased (between 0.1–0.01 m2 s?1 and 1–0.1 m2 s?1 for the bulk and fault zone scenarios, respectively). A permeability–depth decay model would have also satisfied the 5‐year time lag criterion. We also tested several injection management scenarios including redistributing injection volumes between various wells and lowering the total volume of injected fluids. Scenarios that reduced computed excess heads by over 50% within the crystalline basement resulted from reducing the total volume of reinjected fluids by a factor of 2 or more.  相似文献   
36.
    
This study deployed statistical and spatial (GIS) analyses to test the effects of geographic, demographic and occupational factors in predicting health centre visits among the elderly (≥60 years) with chronic ailments in Kanchanaburi Province, western Thailand. Datasets from the Kanchanaburi Demographic Surveillance System (2004 baseline survey and a 2006 project follow-up) comprised five land-use landscape and occupational strata: urban/semi-urban (industrial), rice field, plantation crop, upland and mixed economy. Travel distance to the nearest health centre was calculated following transportation routes and the GPS coordinates of individual home locations, and the number of healthcare visits under the national free universal coverage (UC) scheme reported for the previous year was used as a dependent variable in regressions. Broadly, the study found that distance was not a significant predictor of the rate of elderly health centres visits for those with co-residing spouses and/or adult children (77% of sample), and for the elderly still working (48% of the sample) who were the least likely to access healthcare. Owning motorised vehicles did not encourage visits, which also varied by land-use and occupational strata.  相似文献   
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38.
    
This paper investigates spatial trends of multigenerational adult families in metropolitan Sydney. Australia's immigrant gateway city, Sydney has high housing costs and infrastructure pressures, and planning policies support higher residential densities. In this context, the accommodation of persons living in multigenerational families is examined, by major region of origin, their geographies in Sydney, and by housing costs and constraints. Results highlight that cultural origins were influential in multigenerational household formations, and such formation is higher in areas of first and second ethnic community formation areas. Multigenerational living is also more common in middle ring and outer areas of cheaper housing. Implications are drawn for more nuanced housing policies in Sydney and comparable cities, given that detached and semi‐detached houses were favoured by these households, whereas two‐fifths of new housing constructed in Sydney in 2011 consists of two or less bedroom apartments.  相似文献   
39.
    
al-Tikha is a mid to large Umm an-Nar (c. 2700–2000 BC) settlement situated near Rustaq at the back of the Southern Batinah coastal plain in the Sultanate of Oman that was discovered (or rediscovered) in 2014. The site is unique because its layout and spatial organisation are very largely (possibly completely) visible on the surface. This includes two separate areas of stone-built housing, a large pottery scatter of varying density, three or four typical Umm an-Nar round towers and a small cemetery consisting of at least four tombs, along with a few other features. The layout of the site is described and discussed in detail, in particular, in relation to what it might tell us about the nature of Umm an-Nar settlement and social organisation more generally. The location of the site within a pattern of repeating Umm an-Nar settlement along Wadi Far (Wādī al-Farʿī) is also described and discussed.  相似文献   
40.
The punctuated equilibrium theory (PET) shows that government policy is mostly stable with occasional drastic change, which scholars attribute to institutional friction and limited information processing capacity. Although the existing PET literature predominantly focuses on democracies, scholars have started to apply the theory to authoritarian countries. Autocracies are a fertile testing ground for the theory's underlying mechanisms because they appear to experience less institutional friction but more informational restrictions than democracies. However, PET studies on autocracies are still rare. To deepen our understanding of the PET and the policy process beyond democracies, we conduct a systematic review of 88 Chinese language PET journal articles. We show that Chinese language PET research is increasing. Contrary to the English language PET literature, most Chinese studies are qualitative, while a key similarity is the weak operationalization of PET core concepts. The reviewed studies confirm a punctuated equilibrium pattern of policymaking in China but provide only limited evidence for more intense punctuations compared with democracies. Future PET research on China ought to use long-term data sets and examine institutional friction and information processing by policymakers. We also argue for more international exchange and comparative research to advance our understanding of the policy process in China and other autocracies.  相似文献   
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