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Research on the Cape Saint Paul Wilt Disease (CSPWD) vector in Ghana began from 1990 (1990-1997; 2002-2004) and did not give convincing results. From July 2005, new test standards were applied: shading, daily collections and releasing of insects at the less hot hours and use of various sizes of cages and test plants. More than 70,000 Myndus. adiopodoumeensis were introduced in cage for 28 months (520 adults/seedling/month). Controls in polymerase chain reaction (PCR) on the five coconut of this Myndus cage and on 935 adults were always negative. The tests of transmission with M. adiopodoumeensis apparently not a vector of the disease were thus stopped. The phytoplasma of the CSPWD was identified by PCR in a coconut having received 4,380 Diostrombus (four species of Derbidae) 4 months after the beginning of the test. This coconut never presented symptom of the disease 28 months later and all the successive PCR were negative. Auchenorrhyncha collected by sweeping on the adventitious plants in and around the plot during the day were also tested without success. The hypothesis of a ground transmission was also taken into account because of the presence of scale insects and nematodes.

Metal polychromy has been widely used for decorating metallic artworks from ancient antiquity. In Hellenistic and Roman periods, the famous Corinthian bronzes (Corinthium aes) are a typical example of the skill of metallurgical craftsmen striving to obtain various coloured surfaces on copper based alloys; but the existing investigations are devoted mainly to the 'black bronzes' obtained by oxidation in a wet medium of copper-gold alloys. The present study is part of a general programme devoted to research into different kinds of special surface oxidation treatments on copper alloys and their environmental behaviour. For archaeological objects, such treatments are difficult to observe, as a consequence of corrosion degradation. The examination and analysis of objects kept in the Department of Greek, Etruscan and Roman Antiquities of the Louvre Museum have evidenced the occurrence on one of them, a strigil dated from the first century AD, of a new type of decoration. The strigil is made of copper-zinc alloy, and its decoration exhibits orange-red coloured motifs visibly obtained by chemical oxidation. The present paper describes analyses performed using different techniques: microscopy, particle induced X-ray emission, X-ray diffraction, Rutherford backscattering spectrometry, micro-Raman spectroscopy, spectrophotocolorimetry and optical profilometry. The steps of the decoration process are detailed: the motifs were coloured together with the neighbouring surface. This neighbouring surface was further cleaned by a mechanical process to make the motif coloration appear. The present paper attempts to describe how the Roman craftsman obtained the decorated appearance.

This paper describes microstructural analyses by X-ray portable diffraction and microdiffraction on intentional patina of the bronze museum objects from antique Egypt and the Roman Empire. They bring evidence of the presence in the true black bronze patinas of metallic gold and/or silver presumably as nanoparticles. Three other Egyptian patinas not belonging to black bronze are characterised. Apparent black patination on a Roman scalpel handle is discussed. The discovery of a new patination procedure on Roman artefacts from the Louvre museum is also related, based on intentional high temperature oxidation to obtain a dark patina on a lead bronze object. A presence of lead carbonate cerussite is an important observation.