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Two engraved rocks are situated 140 m from each other at an altitude of about 2250 m. One of them is called “female dancer”, and the other, “the Pleiads”, and both show a group of seven small pitted areas, of which one is smaller than the others and ‘ identified as the “Pleiads stellar cluster”, often depicted or mentioned during Antiquity and also throughout various historical periods.On each of these rocks, a large halberd, whose handle is oriented east-west, was traced along a natural fissure in the rock and engraved in the center of the composition. The “Pleiads stellar cluster” is represented on each of the two rocks beside the halberd : although situated to the west above the halberd blade on the “female dancer” rock, it is placed to the south and to the left of the halberd handle on “the Pleiads” rock. This difference may mark two distinct calendar data.The position of the different figures in the compositions illustrated on these two rocks, in particular inversions in the representation of some of them may indicate two distinct periods of the agricultural yearly cycle: on the rock called “female dancer”, the “heliacal raise” at summer's end, marking the beginning of the harvest and, on the rock called “the Pleiads”, the “heliacal setting”, just before winter, after the end of the harvest, when the rains soaks the ground and it is time to plow.  相似文献   
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Background  

High content screening (HCS)-based image analysis is becoming an important and widely used research tool. Capitalizing this technology, ample cellular information can be extracted from the high content cellular images. In this study, an automated, reliable and quantitative cellular image analysis system developed in house has been employed to quantify the toxic responses of human H4 neuroglioma cells exposed to metal oxide nanoparticles. This system has been proved to be an essential tool in our study.  相似文献   
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Propofol (2,6,di-isopropylphenol) was given by continuous intravenous infusion to provide sedation after cardiac surgery in 30 patients and its effects compared with those of midazolam given to a further 30 patients. Propofol infusion allowed rapid and accurate control of the level of sedation, which was satisfactory for longer than with midazolam. Patients given propofol recovered significantly more rapidly from their sedation once they had fulfilled the criteria for weaning from artificial ventilation and as a result spent a significantly shorter time attached to a ventilator. There were no serious complications in either group. Both medical and nursing staff considered the propofol infusion to be superior to midazolam in these patients. These findings suggest that propofol is a suitable replacement for etomidate and alphaxalone-alphadolone for sedating patients receiving intensive care.  相似文献   
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Several human occupations have been identified within the deposits of the Caune de l’Arago Cave site, dated from 700 000 years to 100 000 years old. The exceptional wealth of these archeological levels provides an opportunity for the study of different types of habitat and behavioral patterns of Paleolithic hunters between 600 000 and 400 000 years ago. Results from preliminary studies, carried out over the last 30 years on these archeological levels, allow for the proposition of a typology for cave habitats during the Middle Pleistocene in the south of France. In fact, four types of habitat were identified and defined. They have been described according to different characteristics such as, the thickness of the archeological accumulation, the animal species represented, the season during which the animals were hunted, the state of conservation of the fossils discovered, the morpho-technological and typological characteristics of the lithics, the categories of raw materials used and the territory exploited by the hominids inhabiting the cave, as defined by the raw materials represented. The four habitation types defined are: the long duration habitat, where the cave was used as a home base; the temporary seasonal habitat, in which case the cave served as a secondary campsite; the hunting stopover and the bivouac, during which the cave was used as a refuge for short term stays. Behavioral patterns appear to be directly related to the type of habitat and oriented towards a principal activity: hunting. The activities performed by the inhabitants of the cave seem to be more diversified during prolonged or seasonal occupations, whereas they appear to be reduced or very specialised during brief stays. Generally, The characteristics studied show that the Caune de l’Arago Cave site had multiple uses over time for Anteneandertalian family groups and hunters who left traces of their activities, allowing us to better understand their lifestyle.  相似文献   
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