Quantitative measurement of metal ions concentration of proteins separated by electrophoresis

peer reviewedThis communication is devoted to nature determination and quantification by PIXE of metals contained in proteins after their separation by PolyAcrylamide Gel Electrophoresis (PAGE). After the electrophoresis, the gel is dried and each track is scanned with a 2.5 MeV proton beam which triggers metal X-ray fluorescence and then, allows to determine the type of metals contained in an electrophoretic band. For quantitative determination of the amount of the metal contained inside the band, the characteristic X-ray peak area is compared with those obtained with polyacrylamide gels doped with the same metal. The normalization has been achieved by using RBS measurements on the gel itself. The procedure presented seems to be a very useful multielementary method for the metal content analysis and for the determination of the metal amounts inside proteins after their separation by electrophoresis. Furthermore it allows to check if metals remain bound to proteins

Hyperplasie congénitale des surrénales Forme classique

peer reviewedL'hyperplasie congénitale des surrénales (HCS) définit un groupe de maladies autosomiques récessives dont le déficit en 21-hydroxylase est de loin la forme la plus fréquente. Cette maladie présente une bonne corrélation entre phénotype et génotype. Afin d'assurer une prise en charge précoce, un dépistage néonatal existe. Deux formes sont décrites, la forme classique, virilisante avec ou sans perte de sel et la forme non classique à révélation plus tardive. La forme classique représente la première cause d'ambiguïté sexuelle chez la fille. Un traitement anténatal peut être proposé si le foetus est à risque d'HCS dans sa forme classique. Dans les deux sexes, le traitement est constitué de glucocorticïdes associés, si nécessaire, à des minéralocorticoïdes dont l'adaptation doit permettre une croissance staturale, une puberté et une fertilité satisfaisantes

Use of a variable incidence angle PIXE arrangement for studying pigment multilayers

Particle induced X-ray emission (PIXE) method is used in the field of archeometry and specially to investigate pigment colored multilayers. The tilting of the sample with respect to the incident proton beam direction allows to modify the relative contribution of each layer to the fluorescence signal. The experimental results coupled to computer simulations lead to semi-quantitative information about the thickness, the position and the composition of the successive layers. (C) 1998 Elsevier Science B.V

Study of medieval glass fragments originating from Savona (Italy) and their relation with the glass produced in Altare

peer reviewedaudience: researcher, professional, studentAltare was in the medieval and post-medieval period an important glassmaking center in the Liguria region in Northern Italy. The first historical evidence of glassmaking in Altare is dated to the twelfth century. In spite of that, due to the continuity of glassmaking up to the present time and the contemporaneous intensive urbanization of the territory, no medieval glass from Altare or its immediate vicinity has been analyzed up to now. In this work, glass from archaeological excavations in the center of Savona, city with close ties with the glassmaking center, was studied. Glass fragments, dated from the tenth to the sixteenth century were selected from the collections of the Archaeological Museum in Savona and non-destructively analyzed with quantitative PIXE-PIGE. The resulting compositions, compared with known glass productions of the same time and evaluated on the basis of historical documents, offer an interesting panorama on the variety of glass circulation in Liguria

The colours of the pilasters, clipei and masks of the Chiragan villa. a work in progress

peer reviewedThe aim of the presentation is to discuss the ongoing study of the polychromy on marble sculptures from the villa of Chiragan (Martres-Tolosane, France), exposed at the Saint-Raymond Museum in Toulouse. This exceptional collection, dating from the long period of occupation of the villa (1st - 4th century), is composed by sixty portraits, mainly in oriental marble, as well as by a group of mythological sculptures and architectural decorations in local marble (Saint-Béat), including ornamental elements and masks. Pilasters, clipei and masks – some bacchic, others from theatrical repertoire – will be, here, examined. Following an analytical protocol, coupling visual observation through white light, UVL and IR, optical videomicroscopy and MA-XRF analysis, we confirm the presence of the pictorial finishing and the compositional nature of the preserved colours. In order to better understand and interpret the results of the physico-chemical analyses, and to sketch some elements of restitution, the analysed objects are systematically compared to the same objects represented in other coloured supports (wall paintings, mosaics or even the real materials in which the represented elements were made). The results of this work in progress may provide a better understanding of the initial appearance of certain works and, from a museographic point of view, a renewed reflection on the presentation of these works in the Musée Saint-Raymond in Toulouse and their visual impact

Development of a Reference Database for Particle-Induced Gamma-ray Emission spectroscopy

Particle-Induced Gamma-ray Emission (PIGE) is a powerful analytical technique that exploits the interactions of rapid charged particles with nuclei located near a sample surface to determine the composition and structure of the surface regions of solids by measurement of characteristic prompt γ rays. The potential for depth profiling of this technique has long been recognized, however, the implementation has been limited owing to insufficient knowledge of the physical data and lack of suitable user-friendly computer codes for the applications. Although a considerable body of published data exists in the nuclear physics literature for nuclear reaction cross sections with γ rays in the exit channel, there is no up-to-date, comprehensive compilation specifically dedicated to IBA applications. A number of PIGE cross-section data had already been uploaded to the Ion Beam Analysis Nuclear Data Library (IBANDL) (http://www-nds.iaea.org/ibandl) by members of the IBA community by 2011, however a preliminary survey of this body of unevaluated experimental data has revealed numerous discrepancies beyond the uncertainty limits reported by the authors. Using the resources and coordination provided by the IAEA, a concerted effort to improve the situation was made within the Coordinated Research Project on the Development of a Reference Database for PIGE spectroscopy, from 2011 to 2015. The aim of the CRP was to create a data library for Ion Beam Analysis that contains reliable and usable data on charged particle γ-ray emission cross sections that would be made freely available to the user community. As the CRP has reached its completion, we shall present its main achievements, including the results of nuclear cross-section evaluations and the development of a computer code that will become available to the public allowing for the implementation of a standardless PIGE technique. © 2015 Elsevier B.V. All rights reserved