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The Naples Yellow pigment was apparently used for the first time by the Egyptians, as a glass-colouring agent. Also known in the Mesopotamian and Roman cultures, the recipe was lost in Western Europe between the fourth and the 16th centuries AD. The recipe for the production of lead antimonate recently discovered in the 'Codice Calabranci' (second half of the 15th century) at Montelupo, a small town near Florence (Italy) known for its large-scale ceramic production, possibly represents the very first evidence of the reintroduction of Naples Yellow in Western Europe after a long period of absence. The major-element composition of the lead antimonate pigment in the Montelupo ceramics of the 15th and 16th centuries is in accordance with the 'Codice Calabranci' recipes. Lead isotope analyses indicate that the lead used to produce the yellow pigments and the underlying glaze of the Montelupo majolica did not come from the Tuscan mining districts, but was possibly imported via Venice from more distant lead sources in Turkey.

In this study, the strontium, neodymium and oxygen isotopic composition of Roman (1st-3rd century AD) and late-Roman glass (4th-6th century AD) from Adria and Aquileia, the two most important archaeological sites of North-Eastern Italy, is discussed.The majority of glass analysed, independent from age, shows values of strontium isotope ratios close to that of modern ocean water, indicating that the source of lime in the glass was marine shell, and likely coastal sands were used in its production. The Nd signature of all Late Roman glasses from Aquileia and of the majority of the Roman ones from Adria, independent from their chemical composition, is homogeneous and higher than -6 εNd, supporting the hypothesis of an eastern Mediterranean origin, probably located on Syro-Palestinian coast. However, the composition of Late Roman samples with HIMT signature, with lower 87 Sr/ 86 Sr values correlated to higher contents in Fe2O3, TiO2, MgO and lower contents in CaO , suggest an area of origin for this glass on the Egyptian coast. In addition, the different Nd signatures of two Adria Roman glasses (εNd < -7) suggests their primary production in western Mediterranean. Oxygen isotopes proved to be a further diagnostic method to discriminate natron and soda plant ash glass, and different silica sources, in the case of the soda plant ash glass. The combination of isotopic and chemical data supports the hypothesis of an eastern Mediterranean origin for Late Roman glass, which may be produced in few primary workshops on the Syro-Palestinian and Egyptian coast, although not necessarily in the same ateliers as have been identified so far. the glass was then imported in the northern Adriatic area. In the case

Embryonic tissues undergoing shape change draw mechanical input from extraembryonic substrates. In avian eggs, the early blastoderm disk is under the tension of the vitelline membrane (VM). Here we report that chicken VM characteristically downregulates tension and stiffness to facilitate stage-specific embryo morphogenesis. While early relaxation of the VM impairs blastoderm expansion, maintaining VM tension in later stages resists the convergence of the posterior body causing stalled elongation, open neural tube, and axis rupture. Biochemical and structural analysis shows that VM weakening follows the reduction of its outer-layer glycoprotein fibers, which is caused by an increasing albumen pH due to CO2 release from the egg. Our results identify a previously unrecognized mechanism of body axis defects through mis-regulation of extraembryonic tissue tension.