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Methane, a potential biosignature, has recently been detected in the martian atmosphere. This Note focuses on field investigations/operational simulations and laboratory studies which resulted in successful detection of methane within arid terrestrial soils, as distinct from the usual methanogen environment, but in at least partial analogy to martian conditions. 相似文献
3.
目的:基于数据挖掘技术探析全国名中医张奇文治疗癫痫的用药规律。方法:收集1998年9月1日至2019年9月30日张奇文治疗癫痫的医案,对医案中的数据进行规范化处理,构建数据库,应用古今医案云平台V2.3.5对中药使用频次、四气五味、功效归经、关联、聚类等进行分析,并总结临床经验。结果:共筛选出40首处方,中药120味。排前10位的中药分别为全蝎、蜈蚣、僵蚕、炙甘草、麦芽、山楂、钩藤、羚羊角、珍珠、牛黄,药性以平、温为主,药味主要为甘、辛、苦,主要归肝、肺、脾经,功效以通络止痛、攻毒散结、息风镇痉等为主。关联组合支持度高的组合为全蝎-蜈蚣、全蝎-僵蚕、僵蚕-蜈蚣、钩藤-全蝎、钩藤-蜈蚣。结论:张奇文治疗癫痫标本兼顾,治标重视息风,治本重视健脾。 相似文献
4.
Accurate numerical continuation of families of plane symmetric direct periodic orbits around the large primary in the Sun-Jupiter case of the restricted problem of three bodies allows the determination of the vertical branching points where families of three-dimensional symmetric periodic orbits bifurcate from the planar ones. Three families of plane periodic orbits, and the initial segments of ten bifurcating families of three-dimensional ones are determined. The stability of these families is examined and examples of their orbits are illustrated. 相似文献
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There are several different approaches currently taken by the 15 EU countries in compiling their IPCC inventories for the FCCC. Six countries (France, Ireland, Italy, Luxembourg, Portugal, Spain) use the CORINAIR system and then aggregate and reformat the data into the required IPCC format. Of the remaining countries, two strictly follow the IPCC methodology (Finland and Greece), five (Denmark, Germany, Netherlands, Sweden, United Kingdom) estimate emissions using a combination of national and IPCC methodologies, while the final two (Austria and Belgium) use a combination of national and CORINAIR methodologies (transformed to IPCC). Comparison of the national inventories in both the IPCC and CORINAIR formats shos some revealing discrepancies between the two systems at both sector and gas level that by chance cancel out when aggregated at the EU level. 相似文献
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Dominique Moran 《GeoJournal》2001,55(2-4):541-547
This paper explores the relationship between the forestry enterprises (leskhozi) and the inhabitants of forestry villages
in the northern rayony of Perm oblast, Russian Federation in the context of the `new regional geography'. These relationships
are compared with those identified between peasant farmers and collective and state farms post-1991, and a theory of the cultivation
of these relationships as a coping mechanism for both households and enterprises facing difficult economic circumstances is
advanced. The situation in the northern rayony is contextualised through discussion of the settlement and development history
of the region, which was a recipient of forced and voluntary labour migration during the Soviet period. The paper concludes
that in accordance with recent theories of post-communist regional development, the experience of transition in the northern
rayony of Perm oblast is determined at least in part by its social and economic context.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
We propose a chronology of late Wisconsinan glacial fluctuations in middle North America, from Alberta to Wisconsin, based on radiocarbon dates derived solely from wood. Previous chronologies of the southwestern margin of the North American Continental Ice Sheet have depended to a considerable degree on radiocarbon dates from fine-grained organic sediment. This material is commonly contaminated with older carbon, resulting in chronologic confusion. By using only dates from wood, much of the confusion disappears. However, because of the scarcity of wood dates, only four of the sixteen identified fluctuations are accurately dated: an advance into Iowa about 14,000 to 13,500 BP, an advance into South Dakota and Iowa about 12,300 BP, an advance into the Lake Michigan basin about 11,700 BP, and an advance into the Lake Superior basin about 9900 BP. In addition, the beginning of late Wisconsinan glaciation, before 20,000 BP, is fairly well documented. None of the fluctuations in the western part of the region are accurately dated. 相似文献
10.
A. R. Breen P. J. Moran C. A. Varley W. P. Wilkinson P. J. S. Williams W. A. Coles A. Lecinski J. Markkanen 《Annales Geophysicae》1998,16(10):1265-1282
Co-rotating interaction regions (CIRs) between fast and slow streams of plasma are a prominent feature of the solar wind. Measurements of interplanetary scintillation (IPS) using the three widely separated antennas of the EISCAT facility have been used to detect the compression regions at the leading edges of interaction regions and to determine the location and velocity of the structure. Observations show that interaction regions have developed as close to the Sun as 25–30 solar radii, a result supported by theoretical modelling which shows that the conditions needed for CIRs to develop exist inside 30 solar radii. 相似文献