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Microscopic analysis of backed lithic pieces from the Uluzzian technocomplex (45-40kya) at the Grotta del Cavallo (southern Italy) reveals their use as mechanically delivered projectile weapons, attributed to Anatomically Modern Humans. Use-wear and residue analysis indicates the lithics were hunting armatures hafted with complex adhesives, while experimental and ethnographic comparison supports their use as projectiles. The use of projectiles conferred a hunting strategy with a higher impact energy and a potential subsistence advantage over other populations and species. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

A micro-sample detached from a historical bowed string instrument represents a valuable record that allows researchers to collect a wealth of information concerning the materials used by the great Masters of violin-making art and to disclose-at least partiallytheir procedures for finishing and varnishing. In the present work, a set of four cross-sectioned micro-samplescollected from well-preserved bowed string instruments made by Antonio Stradivari and Lorenzo Storioni-are investigated by Synchrotron Radiation (SR) FTIR micro-spectroscopy in reflection mode. SR-FTIR spectra are considered both as point analysis and as univariate and multivariate chemical maps. Moreover, data obtained by a non-invasive approach with a portable reflection FTIR spectrometer and SEM-EDX data on the same cross-sections are also considered. FTIR investigation of the cross-sections is a challenging task for such brittle and complex layered micro-samples. Nevertheless, the high intensity of the analytical SR beam used in reflection geometry allowed us to obtain informative FTIR spectra and to fully preserve the integrity of the samples. Both the non-invasive and the micro-invasive reflection FTIR approaches can reveal the materials spread on the wood surface to finish the musical instruments. The fingerprint of Lorenzo Storioni in his production around 1790 is highlighted in the cross sectioned samples, definitely different from the technique of Stradivari.

The two main ageing-inducing events in the collagenous tissues are the water loss and the formation of intermolecular crosslinks based on the reaction of collagen with matrix carbohydrates, following a mechanism known as non-enzymatic-glycation. With the aim to mimic the two deleterious processes for the protein structure, rat-tail collagen was submitted to hydration changes and allowed to interact with two sugars characterized by different reducing properties, D-glucose and D-ribose. Fourier transform infrared (FTIR) spectroscopy was employed to investigate the conformational changes induced in the protein by the two treatments by analyzing the subsequent spectra modifications. FTIR spectra monitored: i) the amplitude and position changes of the two characteristic absorption bands OH stretching and Amide I, in dependence on the humidity level: a significant hysteresis effect in the ν(OH) band (ν~3400 cm–1) amplitude of the protein dehydrated and then rehydrated to the initial relative humidity (aw=0.92- 0.06) may be related to the enhancement of the β-sheet fraction in the protein structure as revealed by the parallel modification in the Amide I band (ν~1650 cm–1); ii) the area of the carbohydrate double band peaking at 1080 cm–1 and 1031 cm–1, associated to the accumulation of the glycation products, depending on the sugar concentration and incubation time. The association of both sugars to collagen only minimally affects the protein secondary structure as revealed by Amide I band Gaussian analysis. The whole set of results suggests hints to hypothesize a self-assembly model for collagen molecules induced by ageing.

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