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In this study, calcite crystals within 42 lapis lazuli reference rocks coming from four distinct mining regions (in present-day Afghanistan, Tajikistan, Siberia and Myanmar) were characterised in terms of their compositional and luminescence properties in order to identify potential provenance markers. A non-destructive approach based on Ion Beam Analysis was employed, in particular using μ-Particle Induced X-rays Emission (μ-PIXE) and μ-Ion Beam Induced Luminescence (μ-IBIL). The results indicate that calcite crystals in Afghan rocks are characterised by the highest quantity of Mg and Mn; whereas, Siberian calcite exhibit the highest Sr content. The application of Principal Component Analysis also enhanced the possibility of discriminating between the Myanmar and Tajik rocks, as well as between the four provenances in general, by exploiting the compositional variability of Mg, Mn, Sr and Y elements. Regarding the luminescence properties, notable differences in the intensity ratio between the 360 nm and the 620 nm luminescence bands were detected among the provenances. In the second part of this study, the new results were employed to infer the origin of the raw material of certain archaeological findings discovered in two different historical sites: four lapis lazuli fragments from Shahr-i Sokhta (Iran, 3rd millennium BCE) and a lapis lazuli tessera from the city of Tanis (Egypt, 1050–700 BCE). The results of the analysis indicate that, among the four provenances considered in the reference rocks database, the best compatibility of the data from both case studies is found with the Afghan dataset. This suggests that the area of Afghanistan is the most probable source for the raw materials of the investigated findings.

This work presents an upgrade to the methodology adopted to investigate the provenance of the raw lapis lazuli material used in antiquity for carving precious artefacts. Samples from archaeological excavation contexts frequently display superficial degradation processes affecting the crystals of the mineral phases useful for provenance attribution (especially pyrite). To address this issue, an innovative workflow has been developed, centred on the application of X-ray micro-computed tomography (μ-CT) and micro-ablation treatments with a pulsed laser source prior to investigation with ion beam analysis (IBA). High-resolution μ-CT is employed to evaluate the alteration state of pyrite crystals within the entire volume of the lapis lazuli rock, and, if required, to identify the most suitable crystals on the surface for subsequent laser treatment. The micro-ablation procedure aims to create a small breach in the superficial altered layer (the irradiated areas are approximately 65 × 65 μm 2 ), thereby exposing the preserved crystal beneath and allowing for the analysis of its trace element contents with IBA. The methodology of the workflow is presented, together with its first application to archaeological lapis lazuli material: three precious beads from the ancient Royal Cemetery of Ur (Mesopotamia, 3rd millennium BCE). The results are complemented by the application of a provenance protocol already validated that proved, for the first time using a micro-invasive analytical approach, a match between the Afghan quarry district and the raw material used to carve these beads.

The restoration of the rose (15th century) of the Sainte-Chapelle in Paris, France, offered a unique opportunity to investigate the color and chemical composition of these emblematic medieval French stained glasses with non-destructive analyses. The obtained results are aimed at complementing the knowledge from art historians and thus together trying to compensate for the total absence of archives on the construction of the rose. Comparison with the glasses of the nave (13th century) reveals an important evolution of the aesthetics based on new types of glasses: new colors and extensive use of flashed glass. The systematic study of the chemical composition of both sides of each glass piece revealed that about half of the studied glasses were flashed. For non-flashed glasses, this comparison allowed evaluating the influence of glass surface weathering, although very moderate, on the composition variability. In light of the variability criteria, the multivariate analysis of the chemical composition allowed inferring that most glasses originate from the same production glasshouse. The new colors result from the original composition of flashed glass, allowing superimposing otherwise incompatible redox states of the coloring transition elements. The comparison with the glasses of the nave reveals the glass technology evolution that occurred over two centuries and allowed the production of new glasses for the medieval glaziers at the eve of the Parisian Renaissance.

The provenance of raw lapis lazuli used since the Neolithic Age for the realization of carved artefacts can be pivoting for the reconstruction of ancient trade routes. The role of main provider of this material in ancient times is generally attributed to the Badakhshan quarries (Afghanistan), although other deposits could have been exploited as well since antiquity. The systematic multi-technique analysis of lapis lazuli rocks coming from four known source areas (located in present-day Afghanistan, Tajikistan, Siberia and Chile) has led in the last years to the compilation of a protocol for provenance determination. The protocol is based on differences in the physical–chemical properties measured with non-invasive techniques (Ion Beam Analysis (IBA)), making it suitable also for precious ancient artefacts. In this work, 10 new reference samples from the Mogok quarry (Myanmar), previously subjected to a complete petrographic and mineralogical characterization, have been analysed employing μ -PIXE (Proton Induced X-ray Emission) and μ -IBIL (Ion Beam Induced Luminescence) techniques. The subdivision of Myanmar samples into three groups, previously suggested, is corroborated by diopside trace elements concentrations. The results also allow to include Myanmar as a new provenance in the analytical protocol, indicating that provenance markers such as presence/absence of wollastonite, altered pyrites and Sr content are still valid to discriminate also the Myanmar lapis lazuli from Chilean or Siberian ones. New weaker markers (Zn content in diopside, Se and Cu contents in pyrite) are proposed for the discrimination of Myanmar from Afghan or Tajik provenances; however, from the analysis it arose the need of investigating new mineral phases with IBA to find strong markers for a definitive discrimination with samples from Southwest Asia.

This paper is aimed at studying different pottery sherds excavated in the site of Valcorrente, located in Sicily, occupied in three main periods, dating respectively to the end of the Neolithic period, to the end of the Chalcolithic period, and to the Early Bronze Age. The chemical composition of the pottery sherds has been analysed with Ion Beam techniques at AGLAE facility at Centre de Recherche et Restauration des Musées de France and the results have been treated with principal component analysis in order to extract indications about the ceramic production technology in the area and the evolution in time.

A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania.

Small samples of native gold from Rosia Montana (Apuseni Mts.) and from Cavnic (Baia-Mare district) were scanned by micro-PIXE method to identify especially minor (between 0.1 and 1%) elements and possible micro-inclusions (micro-areas of different composition from the surrounding material - e.g. rich in tellurium and antimony). The samples were also studied using an AXIO IMAGER - Carl Zeiss polarized light microscope and a Scanning Electron Microscope (SEM) from FEI, model Inspect S with an Energy Dispersive X-Ray Spectroscopy (EDAX) unit. Analyzed samples are from recovery obtained by inhabitants from landfills of former mining plants. For Rosia Montana we detected micrometer areas (5µm X 5µm) rich in Ag and Sb and without Au, Sb/Ag ratio being 1/3.5-4.5, polarized light microscopy and SEM-EDAX analysis confirming the presence of pyrargyrite-proustite. For Cavnic-Roata samples, one micro-area revealed at micro-PIXE an important presence of Te (16657 ppm), a significant presence of Sb (2861 ppm) and an increase of Ag content, indicating the presence of a Ag telluride. Polarized light microscopy and SEM-EDAX analysis confirmed the presence of cervelleite and argentite (acanthite). [PUBLICATION ABSTRACT]

The design of complex, competing effects in magnetic systems—be it via the introduction of nonlinear interactions 1 – 4 , or the patterning of three-dimensional geometries 5 , 6 —is an emerging route to achieve new functionalities. In particular, through the design of three-dimensional geometries and curvature, intrastructure properties such as anisotropy and chirality, both geometry-induced and intrinsic, can be directly controlled, leading to a host of new physics and functionalities, such as three-dimensional chiral spin states 7 , ultrafast chiral domain wall dynamics 8 – 10 and spin textures with new spin topologies 7 , 11 . Here, we advance beyond the control of intrastructure properties in three dimensions and tailor the magnetostatic coupling of neighbouring magnetic structures, an interstructure property that allows us to generate complex textures in the magnetic stray field. For this, we harness direct write nanofabrication techniques, creating intertwined nanomagnetic cobalt double helices, where curvature, torsion, chirality and magnetic coupling are jointly exploited. By reconstructing the three-dimensional vectorial magnetic state of the double helices with soft-X-ray magnetic laminography 12 , 13 , we identify the presence of a regular array of highly coupled locked domain wall pairs in neighbouring helices. Micromagnetic simulations reveal that the magnetization configuration leads to the formation of an array of complex textures in the magnetic induction, consisting of vortices in the magnetization and antivortices in free space, which together form an effective B field cross-tie wall 14 . The design and creation of complex three-dimensional magnetic field nanotextures opens new possibilities for smart materials 15 , unconventional computing 2 , 16 , particle trapping 17 , 18 and magnetic imaging 19 . In magnetic double nanohelices, the balance of geometrical effects and dipolar interaction results in strongly coupled three-dimensional spin states. This leads to topological features in the stray field, offering a new route to pattern the magnetic induction.

The combination of optical lithography with a transfer technique based on a sacrificial substrate enables the creation of a 3D-racetrack memory made from state-of-the-art spintronic materials.

Sustained changes in mood or action require persistent changes in neural activity, but it has been difficult to identify the neural circuit mechanisms that underlie persistent activity and contribute to long-lasting changes in behavior. Here, we show that a subset of Doublesex+ pC1 neurons in the Drosophila female brain, called pC1d/e, can drive minutes-long changes in female behavior in the presence of males. Using automated reconstruction of a volume electron microscopic (EM) image of the female brain, we map all inputs and outputs to both pC1d and pC1e. This reveals strong recurrent connectivity between, in particular, pC1d/e neurons and a specific subset of Fruitless+ neurons called aIPg. We additionally find that pC1d/e activation drives long-lasting persistent neural activity in brain areas and cells overlapping with the pC1d/e neural network, including both Doublesex+ and Fruitless+ neurons. Our work thus links minutes-long persistent changes in behavior with persistent neural activity and recurrent circuit architecture in the female brain. Long-term mental states such as arousal and mood variations rely on persistent changes in the activity of certain neural circuits which have been difficult to identify. For instance, in male fruit flies, the activation of a particular circuit containing ‘P1 neurons’ can escalate aggressive and mating behaviors. However, less is known about the neural networks that underlie arousal in female flies. A group of female-specific, ‘pC1 neurons’ similar to P1 neurons could play this role, but it was unclear whether it could drive lasting changes in female fly behavior. To investigate this question, Deutsch et al. stimulated or shut down pC1 circuits in female flies, and then recorded the insects’ interactions with male flies. Stimulation was accomplished using optogenetics, a technique which allows researchers to precisely control the activity of specially modified light-sensitive neurons. Silencing pC1 neurons in female flies diminished their interest in male partners and their suitor’s courtship songs. Activating these neural circuits made the females more receptive to males; it also triggered long-lasting aggressive behaviors not typically observed in virgin females, such as shoving and chasing. Deutsch et al. then identified the brain cells that pC1 neurons connect to, discovering that these neurons are part of an interconnected circuit also formed of aIPg neurons – a population of fly brain cells that shows sex differences and is linked to female aggression. The brains of females were then imaged as pC1 neurons were switched on, revealing a persistent activity which outlasted the activation in circuits containing both pC1 and aIPg neurons. Thus, these results link neural circuit architecture to long lasting changes in neural activity, and ultimately, in behavior. Future experiments can build on these results to determine how this circuit is activated during natural social interactions.