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1.
Article in English | MEDLINE | ID: mdl-19111503

ABSTRACT

Green colored samples on wall paintings and green powder from a pigment pot found in Pompeii area are investigated by micro-Raman, FT-IR and, for one sample, SEM-EDX. To obtain the green color, green earths and malachite were used, together with mixture of Egyptian blue and yellow ochre. The mineralogical identification of the green earths has been attempted through the comparison of the vibrational features, discriminating between celadonite and glauconite spectra. Traces of a modern synthetic pigment containing copper phthalocyanine were found in a fresco fragment.


Subject(s)
Coloring Agents/analysis , Minerals/analysis , Paintings/history , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , History, Ancient , Microscopy, Electron, Scanning , Organometallic Compounds/analysis , Powders/analysis
2.
Science ; 317(5834): 111-4, 2007 Jul 06.
Article in English | MEDLINE | ID: mdl-17615355

ABSTRACT

It is difficult to obtain fossil data from the 10% of Earth's terrestrial surface that is covered by thick glaciers and ice sheets, and hence, knowledge of the paleoenvironments of these regions has remained limited. We show that DNA and amino acids from buried organisms can be recovered from the basal sections of deep ice cores, enabling reconstructions of past flora and fauna. We show that high-altitude southern Greenland, currently lying below more than 2 kilometers of ice, was inhabited by a diverse array of conifer trees and insects within the past million years. The results provide direct evidence in support of a forested southern Greenland and suggest that many deep ice cores may contain genetic records of paleoenvironments in their basal sections.


Subject(s)
Amino Acids/analysis , DNA/analysis , Ecosystem , Ice Cover/chemistry , Invertebrates , Plants , Trees , Amino Acids/history , Amino Acids/isolation & purification , Animals , Bayes Theorem , Climate , DNA/history , DNA/isolation & purification , Fossils , Geography , Greenland , History, Ancient , Invertebrates/classification , Invertebrates/genetics , Plants/classification , Plants/genetics , Polymerase Chain Reaction , Time
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