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1.
Nature ; 548(7666): 214-218, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783727

RESUMO

The origins of the Bronze Age Minoan and Mycenaean cultures have puzzled archaeologists for more than a century. We have assembled genome-wide data from 19 ancient individuals, including Minoans from Crete, Mycenaeans from mainland Greece, and their eastern neighbours from southwestern Anatolia. Here we show that Minoans and Mycenaeans were genetically similar, having at least three-quarters of their ancestry from the first Neolithic farmers of western Anatolia and the Aegean, and most of the remainder from ancient populations related to those of the Caucasus and Iran. However, the Mycenaeans differed from Minoans in deriving additional ancestry from an ultimate source related to the hunter-gatherers of eastern Europe and Siberia, introduced via a proximal source related to the inhabitants of either the Eurasian steppe or Armenia. Modern Greeks resemble the Mycenaeans, but with some additional dilution of the Early Neolithic ancestry. Our results support the idea of continuity but not isolation in the history of populations of the Aegean, before and after the time of its earliest civilizations.


Assuntos
Etnicidade/genética , Filogenia , Cromossomos Humanos X/genética , Etnicidade/história , Feminino , Grécia , História Antiga , Migração Humana/história , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal
2.
Sci Total Environ ; 308(1-3): 111-9, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12738205

RESUMO

This paper is an attempt to contribute to the discussion started in the 1980s and continuing until today, on the origin of orange-brown patinas observed on marble surfaces. SEM and XRD were used in the study of the orange-brown patina growing at the east stoa of Propylaea, at the Acropolis of Athens. The patina consists of an extremely compact, homogenous, 500-microm-thick layer, mainly of hydroxyapatite. The outer part (50 microm) of the layer presents an orange colour attributed to iron in clay particles, which were deposited on the surface of the patina and have gradually been diffused in the bulk. The interface between the phosphatic layer and the marble is very uneven and full of cavities colonised by microorganisms. The phosphatic layer penetrates into the grain boundaries and fills the empty space between the grains. The presence of biological attack at the interface causes progressive erosion and detachment of both the patina and the marble. The minimum presence of oxalates, the absence of microorganisms or remnants of them in the phosphatic layer, the homogeneity and compactness of the patina, give evidence against the theory of biogenic origin. It is suggested that the layer originates from an artificial coating deliberately applied onto the marble surface for protective or aesthetic reasons, when the marble had already been weathered. Possible manmade pastes are suggested.

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