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There is considerable evidence of widespread damage in the 7th millennium habitation sites across Jordan. The origins of this damage are unknown, but the most widely accepted hypothesis associates the resulting rubble and gravel deposits with the Holocene Rapid Climate Change. One way of testing the various hypotheses is to provide a more reliable chronology for the event(s) in question. In this study, we used quartz OSL and feldspar IRSL signals to date accumulative rubble layers at two archaeological sites in Southern Jordan; Ba'ja and Basta. By comparison with the OSL ages, the IRSL ages demonstrate that most of the quartz samples were sufficiently well bleached at deposition to provide accurate ages. Quartz ages show that deposition of the rubble layers took place in different episodes starting around 8.5 ka and 6.0 ka. Ages from Ba'ja site agree with the archaeological expectations of time of deposition. However, the results from Basta are younger than the archaeological expectations, which are based mainly on architectural style and stratigraphy. 相似文献
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采用细胞计数法,研究了重要经济微藻——雨生红球藻对10种基因工程常用选择试剂的敏感性。结果表明,雨生红球藻对除草剂草丁膦和抗生素Zeocin比较敏感,50μg/ml的草丁膦和25μg/ml的Zeocin可明显地抑制雨生红球藻生长,尤其是50μg/ml的草丁膦能导致细胞两周内全部死亡;高浓度的卡那霉素和硫酸链霉素也可抑制雨生红球藻的生长;雨生红球藻对包括氯霉素和G418在内的其他6种试剂不敏感,即使处理浓度高达1000μg/ml。本文结果提示草丁膦可能是雨生红球藻基因工程适宜的选择试剂,其相应的抗性基因bar可能成为雨生红球藻遗传转化的选择标记基因。 相似文献
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Philipp Garbe Amr Abd El-Raouf Ashraf Es-Senussi Eva Lange-Athinodorou Julia Meister 《Geoarchaeology》2024,39(1):17-34
In ancient Egypt, lakes, canals, and other water bodies were an essential part of the sacred landscape in which temples were embedded. In recent years, geoarchaeological research at the site of the Temple of Bastet at Bubastis in the southeastern Nile Delta has proven the existence of two water canals surrounding the temple. It has now been investigated whether these canals were connected to the Temple of Pepi I (2300–2250 B.C.E.), located approximately 100 m to the west of the Temple of Bastet. To explore the Holocene landscape genesis of the Temple of Pepi I, 15 drillings and six geoelectrical profile lines were performed in the surroundings of the temple in spring 2022. The results show loamy to clayey sediments in deeper sections of all drillings with a maximum thickness of 1.70 m, indicating a marshy or swampy depositional environment. Based on the recovered sediment sequences and archaeological remains in the vicinity of the Temple of Pepi I, the marshy or swampy area existed before the Fourth Dynasty. During the Old Kingdom (ca. 2850–2180 B.C.E.), the former marshland either dried up through natural processes or was intentionally drained and filled with sediments for subsequent use for occupation. Regarding the original research question, there is as yet no evidence for a direct connection to the canals of the Temple of Bastet. 相似文献
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