455 research outputs found

    A portable X-ray fluorescence device for in situ analyses of mural paintings

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    Within the context of a research program for studying with nondestructive methods the preparation and realisation techniques of mural paintings used in the Roman age, a portable ED-XRF device for elemental analysis has been set up. Preliminary tests have been carried out on two Roman mural paintings belonging to the Baia Archaeological Complex (Naples). Datable to different periods, the two paintings show different manufacturing and conservation states, thus representing a good test for verifying the ED-XRF device capability. In situ and laboratory measurements, performed on materials of different origin and nature, have permitted the determination of the pigments and the recognition of pollution traces

    A portable X-ray fluorescence device for in situ analyses of mural paintings

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    Within the context of a research program for studying with nondestructive methods the preparation and realisation techniques of mural paintings used in the Roman age, a portable ED-XRF device for elemental analysis has been set up. Preliminary tests have been carried out on two Roman mural paintings belonging to the Baia Archaeological Complex (Naples). Datable to different periods, the two paintings show different manufacturing and conservation states, thus representing a good test for verifying the ED-XRF device capability. In situ and laboratory measurements, performed on materials of different origin and nature, have permitted the determination of the pigments and the recognition of pollution traces

    Pirfenidone and Nintedanib in idiopathic pulmonary fibrosis: Real-life experience in an Italian referral centre

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    Background: Idiopathic pulmonary fibrosis has a median survival time after diagnosis of 2–5 years. The main goal of treating IPF is to stabilize or reduce the rate of disease progression. Nintedanib and Pirfenidone have been a breakthrough in the management of IPF. Here we evaluated the effectiveness of Pirfenidone and Nintedanib in a population of IPF patients diagnosed in the last 12 months at Florence ILD Referral Centre. Methods: In the last 12 months, 82 IPF patients (66 male, mean age 78.3 ± 23.8 years) were diagnosed and started antifibrotic therapy with Pirfenidone or Nintedanib. Their clinical and functional details were analyzed retrospectively at time 0 and after 6 and 12 months of therapy. Results: The median age of the patients treated with Nintedanib was higher than that of the Pirfenidone group (p 0.05). After 1 year, lung function test parameters of patients treated with Pirfenidone had remained stable from baseline. Discussion: This study emphasizes that both antifibrotic drugs appeared to be a good therapeutic choice in terms of functional stabilization, also in older patients

    Polar and non-polar organic binder characterization in Pompeian wall paintings: comparison to a simulated painting mimicking an a secco technique.

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    The use of Fourier transform infrared spectromicroscopy and mass spectrometry (MS) allowed us to characterize the composition of polar and non-polar binders present in sporadic wall paint fragments taken from Pompeii's archaeological excavation. The analyses of the polar and non-polar binder components extracted from paint powder layer showed the presence of amino acids, sugars, and fatty acids but the absence of proteinaceous material. These results are consistent with a water tempera painting mixture composed of pigments, flours, gums, and oils and are in agreement with those obtained from a simulated wall paint sample made for mimicking an ancient "a secco" technique. Notably, for the first time, we report the capability to discriminate by tandem MS the presence of free amino acids in the paint layer

    Tracing the footprints of SARS-CoV-2 in oceanic waters

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    The detection of SARS-CoV-2 in water environments has predominantly focused on wastewater, neglecting its presence in oceanic waters. This study aimed to fill this knowledge gap by investigating the occurrence of SARS-CoV-2 in remote sea and oceanic waters, at large distances from the coastline. Forty-three 500-liter samples were collected between May 2022 and January 2023 from the Atlantic Ocean, the Mediterranean Sea, the Arctic region, the Persian Gulf and the Red Sea. Using molecular detection methods including real-time RT-qPCR and nested PCR followed by sequencing, we successfully detected SARS-CoV-2 RNA in 7 of the 43 marine water samples (16.3 %), and specifically in samples taken from the Atlantic Ocean and the Mediterranean Sea. The estimated concentrations of SARS-CoV-2 genome copies in the positive samples ranged from 6 to 470 per 100 l. The presence of mutations characteristic of the Omicron variant was identified in these samples by amplicon sequencing. These findings provide evidence of the unforeseen presence of SARS-CoV-2 in marine waters even at distances of miles from the coastline and in open ocean waters. It is important to consider that these findings only display the occurrence of SARS-CoV-2 RNA, and further investigations are required to assess if infectious virus can be present in the marine environment

    Characterization of pigments and ligands in a wall painting fragment from Liternum archaeological park (Italy).

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    Spectroscopic and MS techniques were used to characterize the pigments and the composition of polar and nonpolar binders of a stray wall painting fragment from Liternum (Italy) archaeological excavation. X-ray fluorescence and diffraction analysis of the decorations indicated mainly the presence of calcite, quartz, hematite, cinnabar, and cuprorivaite. Infrared spectroscopy, GC coupled to flame-ionization detector, and MS analysis of the polar and nonpolar components extracted from paint layers from three different color regions revealed the presence of free amino acids, sugars, and fatty acids. Interestingly, LC-MS shotgun analysis of the red painting region showed the presence of αS1-casein of buffalo origin. Compared to our previous results from Pompeii's wall paintings, even though the Liternum painting mixture contained also binders of animal origin, the data strongly suggest that in both cases a tempera painting technique was utilized

    Investigation of conduction band structure, electron scattering mechanisms and phase transitions in indium selenide by means of transport measurements under pressure

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    In this work we report on Hall effect, resistivity and thermopower measurements in n-type indium selenide at room temperature under either hydrostatic and quasi-hydrostatic pressure. Up to 40 kbar (= 4 GPa), the decrease of carrier concentration as the pressure increases is explained through the existence of a subsidiary minimum in the conduction band. This minimum shifts towards lower energies under pressure, with a pressure coefficient of about -105 meV/GPa, and its related impurity level traps electrons as it reaches the band gap and approaches the Fermi level. The pressure value at which the electron trapping starts is shown to depend on the electron concentration at ambient pressure and the dimensionality of the electron gas. At low pressures the electron mobility increases under pressure for both 3D and 2D electrons, the increase rate being higher for 2D electrons, which is shown to be coherent with previous scattering mechanisms models. The phase transition from the semiconductor layered phase to the metallic sodium cloride phase is observed as a drop in resistivity around 105 kbar, but above 40 kbar a sharp nonreversible increase of the carrier concentration is observed, which is attributed to the formation of donor defects as precursors of the phase transition.Comment: 18 pages, Latex, 10 postscript figure

    Assessing the Impact of Household Participation on Satisfaction and Safe Design in Humanitarian Shelter Projects

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    Participation has long been considered important for post‐disaster recovery. Establishing what constitutes participation in post‐disaster shelter projects, however, has remained elusive, and the links between different types of participation and shelter programme outcomes are not well understood. Furthermore, recent case studies suggest that misguided participation strategies may be to blame for failures. This study analysed 19 shelter projects implemented in the Philippines following Typhoon Haiyan in November 2013 to identify the forms of participation employed. Using fuzzy‐set qualitative comparative analysis, it assessed how household participation in the planning, design, and construction phases of shelter reconstruction led to outcomes of household satisfaction and safe shelter design. Participation was operationalised via eight central project tasks, revealing that the involvement of households in the early planning stages of projects and in construction activities were important for satisfaction and design outcomes, whereas engagement during the design phase of projects had little impact on the selected outcomes.National Science Foundation, United States Agency for International Development Office of U.S. Foreign Disaster Assistance, Nicolas R. and Nancy D. Petry Fellowship in Construction Engineering and Managemen

    Biomolecular NMR at 1.2 GHz

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    The development of new superconducting ceramic materials, which maintain the superconductivity at very intense magnetic fields, has prompted the development of a new generation of highly homogeneous high field magnets that has trespassed the magnetic field attainable with the previous generation of instruments. But how can biomolecular NMR benefit from this? In this work, we review a few of the notable applications that, we expect, will be blooming thanks to this newly available technology.Comment: 17 pages, 13 figure

    Spectroscopic and Mechanistic Studies of Heterodimetallic Forms of Metallo-β-lactamase NDM-1

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    In an effort to characterize the roles of each metal ion in metallo-β-lactamase NDM-1, heterodimetallic analogues (CoCo-, ZnCo-, and CoCd-) of the enzyme were generated and characterized. UV–vis, 1H NMR, EPR, and EXAFS spectroscopies were used to confirm the fidelity of the metal substitutions, including the presence of a homogeneous, heterodimetallic cluster, with a single-atom bridge. This marks the first preparation of a metallo-β-lactamase selectively substituted with a paramagnetic metal ion, Co(II), either in the Zn1 (CoCd-NDM-1) or in the Zn2 site (ZnCo-NDM-1), as well as both (CoCo-NDM-1). We then used these metal-substituted forms of the enzyme to probe the reaction mechanism, using steady-state and stopped-flow kinetics, stopped-flow fluorescence, and rapid-freeze-quench EPR. Both metal sites show significant effects on the kinetic constants, and both paramagnetic variants (CoCd- and ZnCo-NDM-1) showed significant structural changes on reaction with substrate. These changes are discussed in terms of a minimal kinetic mechanism that incorporates all of the data
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