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141.
142.
Van Driel-Gesztelyi  L.  Wiik  J.E.  Schmieder  B.  Tarbell  T.  Kitai  R.  Funakoshi  Y.  Anwar  B. 《Solar physics》1997,174(1-2):151-162
Observations of the post-flare loops after the X3.9 flare which occurred on 25 June, 1992 at 20:11 UT by the Yohkoh/SXT in X-rays, as well as in H obtained at 5 different observatories, have provided a unique, longest ever, set of data for a study of the relationship between the hot and cool post-flare loops as they evolve. At any given time, the altitude difference between the hot X-ray loops of 6–7× 106 K and the cool H loops of 1.5× 104 K is related to the expansion rate of the loop systems and their cooling time. Therefore, measurements of the expansion rate and relative height of hot and cool loops can provide direct observational values for their cooling times. We measured the altitude of hot and cool loops for 15 and 19 hours, respectively, and found that the cooling time increased as the density of the loops decreased. We found a reasonably good agreement between the observed cooling times and those obtained from model calculations, although the observed values were always somewhat longer than the theoretical ones. Taking into account evolutionary effects, we also found similar shapes and configurations of hot and cool loops during the entire observing period and confirmed that, at any time, hot loops are at higher altitude than cool loops, suggesting that cool loops indeed evolve from hot loops. These results were used to check the validity of the reconnection model.  相似文献   
143.
The Aeta Magbukún of Bataan in Luzon, the Philippines remain one of the least known and documented Indigenous tribes. They retain primarily subsistence hunter‐gathering strategies to supply their basic needs. They also strive for recognition of their ancestral connection with, and rights to inhabit their ancestral forest domains, which is threatened by the expansion of agriculture and urban development by non‐Aetas, primarily the majority Tagalog population. The Aeta continue to endure dispossession, poverty and political discrimination through decades of protracted land rights processes. This review explores the potential use of recent genetic evidence in anthropology and human geography to legitimize the Aeta's status as Indigenous people and contradict the perspective of some governments in the Asia Pacific region who question the existence of Indigenous peoples generally, often from fear of land tenure and associated political repercussions. The acquisition and use of genetic research on Indigenous populations is both socially and politically contested through fear of the potential to jeopardize sovereignty claims and lead to biologically‐based discrimination. However, the full implications of the potential use of genetic research to legitimize Indigenous status, as described within this research, has yet to be thoroughly explored. By exploring both the genetic and anthropological evidence using a case study of the Indigenous Aeta, this paper provides a unique approach to building a case for Indigenous rights, occupation, use of ancestral lands, self‐determination, and ultimately, recognition as Indigenous people.  相似文献   
144.
Natural Hazards - This study reconstructs the coastal subsidence over the past 1300 years in a mangrove region along the coast of the Ganges–Brahmaputra Delta, an area not affected...  相似文献   
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