The tin content of lead inclusions in ancient tin-bronze artifacts: a time-dependent process?

In antiquity, Pb was a common element added in the production of large bronze artifacts, especially large statues, to impart fluidity to the casting process. As Pb does not form a solid solution with pure Cu or with the Sn-Cu alloy phases, it is normally observed in the metal matrix as globular droplets embedded within or in interstitial positions among the crystals of Sn-bronze (normally the α phase) as the last crystallizing phase during the cooling process of the Cu-Sn-Pb ternary melt. The disequilibrium Sn content of the Pb droplets has recently been suggested as a viable parameter to detect modern materials [Shilstein, Berner, Feldman, Shalev & Rosenberg (2019). STAR Sci. Tech. Archaeol. Res. 5, 29-35]. The application assumes a time-dependent process, with a timescale of hundreds of years, estimated on the basis of the diffusion coefficient of Sn in Pb over a length of a few micrometres [Oberschmidt, Kim & Gupta (1982). J. Appl. Phys. 53, 5672-5677]. Therefore, Pb inclusions in recent Sn-bronze artifacts are actually a metastable solid solution of Pb-Sn containing ∼3% atomic Sn. In contrast, in ancient artifacts, unmixing processes and diffusion of Sn from the micro- and nano-inclusions of Pb to the matrix occur, resulting in the Pb inclusions containing a substantially lower or negligible amount of Sn. The Sn content in the Pb inclusions relies on accurate measurement of the lattice parameter of the phase in the Pb-Sn solid solution, since for low Sn values it closely follows Vegard's law. Here, several new measurements on modern and ancient samples are presented and discussed in order to verify the applicability of the method to the detection of modern artwork pretending to be ancient.

A Study of the Radiation Tolerance and Timing Properties of 3D Diamond Detectors.

We present a study on the radiation tolerance and timing properties of 3D diamond detectors fabricated by laser engineering on synthetic Chemical Vapor Deposited (CVD) plates. We evaluated the radiation hardness of the sensors using Charge Collection Efficiency (CCE) measurements after neutron fluences up to 1016 n/cm2 (1 MeV equivalent.) The radiation tolerance is significantly higher when moving from standard planar architecture to 3D architecture and increases with the increasing density of the columnar electrodes. Also, the maximum applicable bias voltage before electric breakdown increases significantly after high fluence irradiation, possibly due to the passivation of defects. The experimental analysis allowed us to predict the performance of the devices at higher fluence levels, well in the range of 1016 n/cm2. We summarize the recent results on the time resolution measurements of our test sensors after optimization of the laser fabrication process and outline future activity in developing pixel tracking systems for high luminosity particle physics experiments.

Microchemical, structural and mineralogical study of ancient Moroccan pyrometallurgical remains and data sharing through the support of a QGIS software.

The mining areas of the Middle Atlas, already inhabited in the Neolithic period, have been under the influences of different cultures, firstly Phoenician, then Punic or Ibero-Punic, Berber, Roman and finally Islamic. The impact of external cultures on the evolution and development of ancient metallurgy in the north-central Atlas region and the Southern Rift occurred since prehistoric times to Arab domination in the Middle Ages. This study proposes the development of an up-to-date protocol for archaeometallurgical investigation, based on the correlation between the chemical-physical analysis of the pyrometallurgical materials and the contextual systematic geoarchaeological excavations. The microchemical analysis has been carried out on opportunely selected pyrometallurgical materials, coming from different mining areas of the Middle Atlas regions in Morocco (Tabarouch for Cu and Aouam for Pb/Ag) in order to understand the evolution of the technological knowledge in archaeometallurgical work of local people. After that, the analytical results have been included in a Geographic Information System (GIS) software with the aim of creating an easily usable database that will support multidisciplinary research on the ancient metallurgical activities also with its future development and implementation. The GIS application could indeed correlate all the data coming from different extraction/work sites, present in the exploited mining veins. Furthermore, the GIS application is a starting point for an integrated study of the different mining archaeological sites in the Mediterranean basin proposing an innovative method of data exchange of archaeological, physical and geological chemical results.

Infant health and neurodevelopmental outcomes following prenatal exposure to duloxetine.

Maternal psychiatric disorders can have negative consequences on the fetus and newborn. Thus, the risks of untreated mental disorders in pregnancy should be balanced against the potential risks of a psychopharmacological treatment. The aim of the present report is to provide information on the infant safety of duloxetine exposure, an antidepressant drug belonging to the serotonin-norepinephrine reuptake inhibitors, during pregnancy. Despite duloxetine being routinely prescribed as a treatment for major depression and anxiety disorders, there is a paucity of literature evaluating both the short- and long-term effects of duloxetine exposure in utero. This paper provides data on infant health and neurodevelopmental outcomes, up to 9 months of age, in a newborn exposed to duloxetine throughout pregnancy. Although the present report suggests that duloxetine was not associated with major malformations or neurobehavioural problems, the drug should be used with caution until further information is available on its safety profile in pregnancy.