A Microcosm of Colour and Shine. The Polychromy of Chryselephantine Couches from Ancient Macedonia

The present work examines the polychromy applied to a number of fragmentary ivory small-scale sculptures that served as components of the luxurious decoration of chryselephantine couches from ancient Macedonia. The ivory fragments come from funerary contexts (the tomb of Philip II at Aigai, the Macedonian tomb II of Korinos at Pydna and the Macedonian tomb III of Aghios Athanassios near Thessaloniki), all of which are dated to the last quarter of the fourth century BC. The use of bright pigments on the laboriously executed faces of the figures and their garments, together with the gold leaf applied onto the hair and the background, conveys a powerful effect of polychromy that would have immediately caught the spectator’s eye, enhancing the overall aesthetic and material value of such lavishly decorated furniture. The identification of the pigments and the techniques of their application have been studied with the use of analytical methods (XRF, micro-XRF, XRD and SEM-EDS) and multi spectral imaging (Visible Induced Luminescence).Le présent article est consacré aux traces de polychromie retrouvées sur un certain nombre de sculptures fragmentaires en ivoire de petit format composant la somptueuse décoration des lits de banquets chryséléphantins de la Macédoine antique. Ces fragments en ivoire ont été découverts dans des sépultures (la tombe de Philippe II à Aigai, la tombe macédonienne II de Korinos à Pydna et la tombe III d’Aghios Athanassios près de Thessalonique, toutes datées du dernier quart du ive siècle avant Jésus-Christ.L’utilisation de pigments éclatants sur les visages soigneusement travaillés des figurines ainsi que sur leurs vêtements, tout comme la feuille d’or, appliquée sur la chevelure et sur le fond, leur confèrent une puissance de chatoiement qui devait immédiatement frapper le spectateur, renforçant l’impression esthétique comme la valeur matérielle de ce mobilier si fastueusement décoré.L’identification des pigments et les techniques de mise en œuvre employées ont été étudiées à l’aide d’analyses en XRF, micro-XRF, DRX, MEB-EDS et de l’imagerie multi-spectrale (photoluminescence

In vitro bioaccessibility of macro and trace elements in biofortified and conventional farmed gilthead seabream (Sparus aurata) and common carp (Cyprinus carpio)

Biofortification is a promising strategy to improve the nutrient profile of farmed fish but requires consideration of the nutrient bioaccessible fraction. In this study, the in vitro bioaccessibility of macro and trace elements was investigated in biofortified and conventional farmed gilthead seabream and common carp, also taking into account the effect of cooking (by steaming). Biofortification enhanced iodine and selenium levels in seabream and carp fillets. Steaming increased iodine and selenium contents in biofortified seabream, and increased selenium and decreased copper levels in biofortified carp. Higher iodine bioaccessibilty (> 80%) was observed in biofortified seabream compared to biofortified carp (45%). In both species, selenium, iron, and zinc bioaccessibility was ≥ 70%. Upon steaming iodine and iron bioaccessibility decreased in seabream, while selenium bioaccessibility decreased in carp. The consumption of steamed biofortified seabream and carp contributes to significantly higher daily intakes of iodine (up to 12% and 10%, respectively) and selenium (up to 54% and above 100%, respectively) compared to conventional counterparts. The present study demonstrates the potential of developing innovative biofortified farmed fish using natural sustainable feed ingredients to improve the intake of important nutrients for human health.Highlights: - Iodine bioaccessibility is 80% in seabream and lower than 50% in carp. - Selenium, iron and zinc bioaccessibility were always above 70%. - Overall, bioaccessibility decreased after steaming (e.g., K: lower than 50%). - The availability of I and Se for absorption following the digestive process was higher in biofortified fillets.This work was supported by the European Union’s Horizon 2020 research and innovation programme under Grant Agreement no. 773400 (SEAFOODTOMORROW).info:eu-repo/semantics/publishedVersio

New Instruments for Nuclear Astrophysics

A major task in experimental nuclear astrophysics is the measurement of cross sections of capture reactions. In the last years, the astrophysics group of NCSR "Demokritos" developed and used a method for conducting this kind of research using a 4π NaI γ-detector. Of great importance in this method is the determination of the efficiency of the detector, which depends on the average multiplicity of the γ-cascade de-exciting the entry state of the produced nucleus. Two new experimental setups have been studied and are in course of installation at the Tandem Laboratory of the Institute of Nuclear and Particle Physics of NCSR "Demokritos", that will provide the possibility for conducting this kind of experiments inhouse. The first one is a new 14x14 inches NaI detector and the second is the BGO Ball of the GASP setup. These detector setups as well as their potential experimental use will be described in detail

Solid-state polymer membranes for simple, sensitive, and low-cost monitoring of mercury in water

Summarization: Solid-state Hg(II) selective membranes were produced and assessed by means of X-ray absorption near edge structure in the total reflection X-ray fluorescence (TXRF-XANES) setup and by the energy dispersive X-ray fluorescence (EDXRF) technique. Membranes were functionalized using four promising ligands for mercury complexation, i.e.: i) 4-(2-Pyridylazo) resorcinol (PAR), ii) thiourea, iii) calconcarboxylic acid (CCS), and iv) dithizone. A simple analytical procedure was followed, using miniscule reagent quantities, thus suggesting the process is also cost-effective. TXRF-XANES revealed that mercury complexes with the ligands, and is not simply adsorbed onto the PVC matrix, while the complexation was found to not be affected by the matrix existence. Mercury exhibited an increased oxidation grade and was covalently bound to the ligand functional groups, via a strong chemical bond. EDXRF revealed that the solid-state membranes can be used for mercury speciation and trace analysis from environmentally relevant matrices, such as tap water. The membranes could be a promising alternative to polymer inclusion membranes (PIMs), due to their simple configuration and high Hg (II) selectivity in aqueous media, but more research is needed. PAR appears to be the most promising ligand, followed by dithizone and thiourea. CCS had a minuscule preconcentration efficiency since it was preferably bound with Cu in tap water, indicating limited usefulness for mercury preconcentration. However, results suggest that, depending on the ligand, the solid-state membranes could be also possibly used for multi-elemental heavy metals analysis in water.Παρουσιάστηκε στο: Science of the Total Environmen

Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M&gt;70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0&lt;e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

New evidence for the use of cinnabar as a colouring pigment in the Vinca culture

This paper presents the results obtained for red pigments used on ceramics from the Neolithic period, excavated at three Vinca culture archaeological sites on the territory of present day Serbia. Emphasis was put on cinnabar, a characteristic red pigment, in order to define its possible origin and usage. Several spectroscopic techniques (EDXRF, PIXE, X-ray powder diffraction) were applied to identify the pigments. According to the results presented in this paper, the known record regarding the first cinnabar use in the Balkans can be extended to the end of the sixth millennium BC. (C) 2011 Elsevier Ltd. All rights reserved

The “lost art” of Archaic Greek painting: revealing new evidence on the Pitsa pinakes through MA-XRF and imaging techniques

In the present work, four wooden panels dated to the second half of the 6th century B.C., discovered in 1934 inside a cave located in Corinthia near the ancient city of Sicyon, are examined. The “Pitsa pinakes” are the oldest known examples of panel painting in ancient Greece. The application of non-invasive and non-contact imaging and analytical techniques (imaging techniques, including infrared-reflected and visible-induced luminescence, microscopy and mapping XRF) has brought to light significant evidence on the materials and the technology of the paintings. Multiple figurative elements that had remained previously “unseen”, due to the losses and degradation of the original paint layers, were recovered, allowing for a better understanding of the original iconography. Furthermore, imaging techniques have largely contributed to an enhanced reading and understanding of the inscriptions preserved on the panels, including the personal name “Kalypso” on the panel depicting a ritual dance (inv. 16467); this name had hitherto been known only through literary sources.La présente étude concerne quatre tablettes en bois de la seconde moitié du vie siècle avant J.-C., découvertes en 1934 dans une grotte située en Corinthie, près de l’antique cité de Sicyone. Les « pinakes de Pitsa » sont les plus anciens exemples connus de peinture sur bois dans la Grèce antique. Les techniques d’imagerie et d’analyse non-invasives hors contact (notamment par réflectographie infrarouge, luminescence induite visible, microscopie et macro-spectrométrie de fluorescence X) ont livré des données importantes sur les matériaux et techniques picturales. En faisant réapparaître de nombreux éléments figuratifs restés inaperçus jusque-là, en raison des lacunes et dégradations des couches picturales antiques, elles ont permis de mieux comprendre l’iconographie originale. En outre, les procédés d’imagerie employés ont contribué à un meilleur déchiffrage des inscriptions préservées sur les tablettes, notamment (sur la tablette 16467) le nom propre Calypso, connu jusque-là uniquement par les sources littéraires

Argon ions deeply implanted in silicon studied by Rutherford/Elastic Backscattering and Grazing Incidence X-ray Fluorescence spectroscopy

Synchrotron-radiation based techniques have recently emerged as serious competitors to traditional nuclear analytical ones, not only in the characterization of various materials, but also when the depth profiling of ultra-thin surface layers is concerned. The main goal of the present work was to investigate the applicability of Grazing Incidence X-Ray Fluorescence (GIXRF) and Rutherford/Elastic Backscattering Spectrometry (RBS/EBS) techniques with respect to the accurate quantitative determination of the retained doses of Ar ions deep implanted in random direction of Si [1 1 1] polished crystalline wafers. RBS/EBS measurements with protons and deuterons were taken along with GIXRF ones, the results were compared and an attempt was made to explain the occurring similarities and differences, along with the advantages and weaknesses of each applied analytical technique. © 2018 Elsevier B.V.23rd International Conference on Ion Beam Analysis (IBA) (2017; Shanghai