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Mouhsin El Mansouri Abderrahmane El Fouikar Bernard Saint-Martin 《Journal of archaeological science》1996,23(6):803-809
The Upper Palaeolithic site of the Abri Pataud (Dordogne, France) has been the subject of numerous14C age determinations which cover the period from 20,400±450 years
(OXA-373) to 34,250±675 years
(Grn-4507). The racemization ratios of aspartic acid have been determined in 26 fossil bones. The bones are present in two different sedimentary surroundings: levels (fine deposits with numerous artefacts and fossil bones) and “éboulis” (coarse deposits derived from the neighbouring limestone cliff). Racemization ratios for total aspartic acid have a poor correlation with14C ages (respectivelyr2=0·59 and 0·82 for the two environments) but apparent racemization rates are clearly dependent on the type of deposits (levels: K=4·4×10−6year−1; éboulis: K=9×10−6year−1).Racemization ratios of aspartic acid in a high molecular weight protein fraction (>10,000 Da) correlate much better with14C ages (r2=0·999) for the samples from the levels (k=2·1×10−5year−1). From this regression line we estimate ages for two Aurignacian levels: level 6≈29,560 years
and level 9≈30,440 years
.It is noteworthy that none of the regression lines intercepts the origin. Racemization of aspartic acid appears to occur only after a delay of many thousands of years. This phenomenon could be the result of a coupling between the degradation of proteins and the racemization of amino acids. 相似文献
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Roland Nespoulet Mohamed Abdeljalil El Hajraoui Fethi Amani Abdelwahed Ben Ncer André Debénath Abdelaziz El Idrissi Jean-Paul Lacombe Patrick Michel Aïcha Oujaa Emmanuelle Stoetzel 《African Archaeological Review》2008,25(1-2):21-39
In the 1970s, the discoveries of Palaeolithic human remains in the caves of Dar es Soltane 2, El Harhoura 1 and Les Contrebandiers reinforced interest in the sites of the Témara region. These sites, often cited, have been the object of numerous investigations which have produced a major contribution to the prehistory of Morocco. Over the past 15 years, research at two key sites, El Mnasra and El Harhoura 2, have considerably enhanced the available data for this region. Preliminary results obtained from excavations since 2001, allow us to present the palaeoenvironmental framework and describe the technological behaviour of prehistoric groups within a re-evaluated stratigraphic context. The microfaunal and macrofaunal assemblages are analysed according to systematics, taphonomy and palaeoecology. The lithic and bone industries document patterns of raw material acquisition and transformation. Within the context of the history of more than 60 years of research in the region of Témara, this contribution allows us to approach the question of Palaeolithic population on the basis of recent, and for the most part new, data and evidence. 相似文献
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Fethi Mansouri 《Australian journal of political science》2007,42(1):129-142
Historically, Australia's interests in the Middle East related primarily to its role in the Commonwealth imperial defence system which resulted in the deployment of Australian forces in the Middle East during both the First and Second World Wars. Similarly, the current involvement of Australian troops in Iraq and Afghanistan is driven by the country's strategic alliance with the United States. However, Australia's current involvement reflects a multifaceted relationship that spans economic, political and strategic spheres. Yet it is at the level of cultural and civilisational contacts that this relationship appears at its most vulnerable. This paper argues that a deeper understanding of this cultural dimension combined with a broader emphasis on good governance and human rights would be conducive to more robust ties in the longer term. 相似文献
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