Violin varnishes: microstructure and nanomechanical analysis

The aim of the current work is twofold: to demonstrate the application of in situ non-invasive imaging by portable atomic force microscopy (AFM) on the surfaces of a violin and to integrate compositional and mechanical analysis at the nano scale level on model samples of varnished wood. These samples were prepared according to traditional recipes by an Italian lutemaker family well practised in the art. Samples of oil and spirit-based varnishes on maple wood, naturally and accelerated light aged, were studied. AFM was used to measure the nanomechanical properties of the model samples and established that the spirit-based varnish was stiffer than the oil-based. Synchrotron radiation micro- Fourier Transform Infra-red analysis of the layer structure revealed that stiffer spirit-based varnish showed less penetration into the wood than the oil-based. Further PeakForce Quantitative Nanomechanical Mapping (QNM) demonstrated a difference in adhesion values between the oil- and spirit-based sample

A First Search for coincident Gravitational Waves and High Energy Neutrinos using LIGO, Virgo and ANTARES data from 2007

We present the results of the first search for gravitational wave bursts associated with high energy neutrinos. Together, these messengers could reveal new, hidden sources that are not observed by conventional photon astronomy, particularly at high energy. Our search uses neutrinos detected by the underwater neutrino telescope ANTARES in its 5 line configuration during the period January - September 2007, which coincided with the fifth and first science runs of LIGO and Virgo, respectively. The LIGO-Virgo data were analysed for candidate gravitational-wave signals coincident in time and direction with the neutrino events. No significant coincident events were observed. We place limits on the density of joint high energy neutrino - gravitational wave emission events in the local universe, and compare them with densities of merger and core-collapse events.Comment: 19 pages, 8 figures, science summary page at http://www.ligo.org/science/Publication-S5LV_ANTARES/index.php. Public access area to figures, tables at https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=p120000

Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

Chromatographic analysis of organic micropollutants in the marine environment.

non disponibil

MULTI-ANALYTICAL TECHNIQUES FOR THE STUDY OF PRE-COLUMBIAN MUMMIES AND RELATED FUNERARY MATERIALS

Due to a paucity of original written information, we base our knowledge of the pre-Columbian civilizations of Latin America on archaeological and archaeometric analysis. Particularly, the analytical study of funerary materials collected by conquerors in historical times and archaeologists nowadays during their travels and expeditions contributes to a better understanding of religious practices and social organisation. In the present study, a multi-analytical approach is presented which was used for the characterisation of red and blue organic dyes, inorganic pigments and embalming materials in various archaeological finds from the necropolis of Anco`n (Peru). These included the funerary clothes belonging to a set of three mummies, dated between the 11th and the 13th century AD. Chromatographic and spectrometric techniques were used: high performance liquid chromatography with UV-Visible detector (HPLC-UV-Vis) for identifying organic dyes, scanning electron microscopy with energy dispersive X-ray spectrometer (SEM-EDX) for recognising pigments, and gas chromatography with mass spectrometric detection (GC/MS) for analysing organic embalming materials. This multi-analytical approach enabled us to characterise a range of materials. The presence of red anthraquinoid dyes and blue indigoid ones was assessed, although it was not always possible to identify the original source with certainty. Cinnabar was identified as the colouring material applied to one mummy’s hair. The molecular markers of conifer resin were detected in the bandages. The analytical results highlighted the use of a number of hitherto unknown dyes and embalming materials in Peruvian funerary rituals

Characterization of proteinaceous binders in old paintings

non disponibil

Determinazione di policlorobifenili (PCB) in campioni di acqua del Sistema Lagunare Veneziano

non disponibil

Characterisation of oriental lacquers from Rhus Succedanea and Melanorrhoea Usitata using in situ pyrolysis/silylation-gas chromatography-mass spectrometry

Two oriental lacquers from Rhus Succedanea and Melanorrhoea Usitata were characterised by Py-GC-MS with in situ silylation using HMDS. Pyrolytic markers, which were helpful in differentiating between the lacquers, were identified in their silylated forms, and the mass spectra are presented and discussed. Aliphatic and aromatic hydrocarbons were formed as well as TMS derivatives of alkylcatechols and alkylphenols, and relative characteristic pyrolytic profiles were compared for the two lacquers. The method, here applied for the first time to the characterisation of the Vietnamese and Burmese lacquers, proved successful not only in distinguishing between the two lacquers, but also in highlighting the polymerisation processes undergone by the saps in the formation of the lacquer layers.The results obtained demonstrated that in situ Py/silylation-GC-MS with using HMDS is a suitable tool for the analysis of all oriental lacquers with possible application to diagnose their presence in samples of unknown composition. © 2015 Elsevier B.V