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51.
Finlayson C Pacheco FG Rodríguez-Vidal J Fa DA Gutierrez López JM Santiago Pérez A Finlayson G Allue E Baena Preysler J Cáceres I Carrión JS Fernández Jalvo Y Gleed-Owen CP Jimenez Espejo FJ López P López Sáez JA Riquelme Cantal JA Sánchez Marco A Guzman FG Brown K Fuentes N Valarino CA Villalpando A Stringer CB Martinez Ruiz F Sakamoto T 《Nature》2006,443(7113):850-853
The late survival of archaic hominin populations and their long contemporaneity with modern humans is now clear for southeast Asia. In Europe the extinction of the Neanderthals, firmly associated with Mousterian technology, has received much attention, and evidence of their survival after 35 kyr bp has recently been put in doubt. Here we present data, based on a high-resolution record of human occupation from Gorham's Cave, Gibraltar, that establish the survival of a population of Neanderthals to 28 kyr bp. These Neanderthals survived in the southernmost point of Europe, within a particular physiographic context, and are the last currently recorded anywhere. Our results show that the Neanderthals survived in isolated refuges well after the arrival of modern humans in Europe. 相似文献
52.
Mantle wedge control on back-arc crustal accretion 总被引:1,自引:0,他引:1
At mid-ocean ridges, plate separation leads to upward advection and pressure-release partial melting of fertile mantle material; the melt is then extracted to the spreading centre and the residual depleted mantle flows horizontally away. In back-arc basins, the subducting slab is an important control on the pattern of mantle advection and melt extraction, as well as on compositional and fluid gradients. Modelling studies predict significant mantle wedge effects on back-arc spreading processes. Here we show that various spreading centres in the Lau back-arc basin exhibit enhanced, diminished or normal magma supply, which correlates with distance from the arc volcanic front but not with spreading rate. To explain this correlation we propose that depleted upper-mantle material, generated by melt extraction in the mantle wedge, is overturned and re-introduced beneath the back-arc basin by subduction-induced corner flow. The spreading centres experience enhanced melt delivery near the volcanic front, diminished melting within the overturned depleted mantle farther from the corner and normal melting conditions in undepleted mantle farther away. Our model explains fundamental differences in crustal accretion variables between back-arc and mid-ocean settings. 相似文献
53.
54.
目的:初步了解龙街乡小兽类哺乳动物分布及蠕虫寄生情况。方法:鼠笼、鼠夹或投药捕获小兽分类鉴定,解剖检查蠕虫寄生情况。结果:共捕获小兽475只,小兽以黄胸鼠为优势种(44.84%),蠕虫总感染率为53.89%。结论:该乡小兽蠕虫感染普遍。 相似文献
55.
56.
Numerical analysis and centrifugal modeling of LNAPLs transport in subsurface system 总被引:3,自引:0,他引:3
The transport of non-aqueous phase liquids (NAPLs) in unsaturated soils and groundwater is an important research topic in geo-environmental engineering. In this paper, the mechanism of light NAPLs (LNAPLs) transport in subsurface system is briefly introduced, and the mass transport equations, fluid flow equations, and the constitutive model of relative permeability - saturation - capillary pressure are discussed. Then the numerical method is introduced to simulate the multiphase flow problems in porous media, and the tempo-spatial distribution of LNAPLs is obtained. Moreover, different boundary conditions are employed in numerical simulation to investigate its effect on transport behavior. To verify the numerical data, centrifugal tests are conducted to model the LNAPLs migration in unsaturated soils and groundwater. The calculation results are agreeable with the experimental findings of centrifugal modeling, which indicates that LNAPLs from leaking point move downwards due to gravity force, and form a high concentration zone above the capillary fringe, and then spread out laterally along the groundwater table. Some LNAPL enters groundwater system to further migrate. The combination of numerical simulation and centrifuge modeling can be a useful means to study the transport behavior of LNAPLs in subsurface system. 相似文献
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58.
A functional variant of SUMO4, a new I kappa B alpha modifier, is associated with type 1 diabetes 总被引:23,自引:0,他引:23
59.
Nurieva R Yang XO Martinez G Zhang Y Panopoulos AD Ma L Schluns K Tian Q Watowich SS Jetten AM Dong C 《Nature》2007,448(7152):480-483
60.
Equivalent spaces of 42K were measured in fragments of the submandibular gland of 1-, 7-, 14- and 21-day-old and adult rats in the absence and presence of carbachol and the transport inhibitors ouabain and furosemide. The results indicate that the 42K space was increased by carbachol in an ouabain-sensitive manner at all ages studied and that part of the secretagogue-stimulated K uptake occurred by way of a furosemide-sensitive transport system in the latter part of the postnatal period and in the adult. 相似文献