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Charles Anyinam 《The Canadian geographer》1990,34(1):69-76
The range of health and health care topics amenable to geographical analyses in Western industralized countries has increased tremendously in the past two decades. These studies of health care systems have focused on the health organization, delivery, and utilization of biomed-ical services, however, to the virtual exclusion of analyses of a wide variety of alternative approaches to health and healing in these countries. This lacuna is regrettable in view of the fact that people's health care behaviour suggests that medical pluralism is a persisting reality in the industrialized countries. There is indeed a coexistence of biomedicine with several alternative therapies and, in recent years, there has been resurgence in the popularity and use of alternative medicine. 相似文献
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Despite uniform geochemistry 40Ar/39Ar ages of 0.6, 1.25, and 1.3 Ma on obsidians from a source flow (Worja) and from archeological artifacts at the sites of Kulkuletti (near Gademotta, Ethiopia) have been interpreted to suggest that they derive from different source flows of different ages. A further suggestion is that the magmatic source of the obsidian flows was chemically homogeneous between 1.3 Ma and 0.6 Ma. Chemical analysis of these obsidians indeed suggests that they derive from a single flow. Reexamination of the argon isotopic data reveals that argon isotopes may have been fractionated within the flow, so that the assumption of an atmospheric 40Ar/36Ar ratio of 295.5 is inappropriate to use for computing ages. Three groups of data are apparent, and internally all yield ages near 1.3 Ma if the intercept value for 40Ar/36Ar from an isotope correlation plot is used for computation instead of using the atmospheric ratio. The Soret thermal diffusion effect provides a possible mechanism of fractionation of argon within the obsidian flow that is of approximately the right magnitude to explain the observations by in-diffusion of already fractionated atmospheric argon. 相似文献