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1.
Microsc Microanal ; 19(2): 420-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23442447

RESUMO

Ferruginous bodies observed in lungs of patients affected by mesothelioma, asbestosis, and pulmonary carcinoma are important to relate the illness to exposure, environmental or occupational, to asbestos. Identification of the inorganic phase constituting the core of the ferruginous bodies, formed around asbestos but also around phases different from asbestos, is essential for legal purposes. Environmental scanning electron microscopy/energy dispersive spectroscopy was used to identify the fibrous mineral phase in the core of ferruginous bodies observed directly in thin sections of tissue, without digestion of the biological matrix. Spectra were taken with sequential analyses along a line crossing the core of the ferruginous bodies. By comparing the spectra taken near to and far from the core, the chemical elements that make up the core could be identified.


Assuntos
Amianto/análise , Neoplasias Pulmonares/patologia , Pulmão/ultraestrutura , Mesotelioma/patologia , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Amianto/toxicidade , Humanos , Pulmão/química , Pulmão/patologia
2.
Mar Pollut Bull ; 196: 115659, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37866055

RESUMO

This work focuses on the arenaceous reefs by the polychaete Sabellaria spinulosa and addresses microplastics pollution. The main aim is to assess microplastics amount in a bioconstruction located in the Adriatic coast of Italy (Mediterranean Sea) through a comparative approach: sea-floor sediment and bioconstruction samples were analysed to quantify microplastics absolute abundance in both substrates. A total of 431 MPs were found in the investigated substrates: respectively 85 % fibers and 15 % fragments. Multivariate analysis indicates that MPs within bioconstruction occur in higher abundances and with different morphologies than in sediment samples. The analysis of bioconstruction polished sections allowed for observation of MPs agglutinated in their original position: higher concentration is reported in inter-tube areas. Results suggest that physical characteristics of MPs could play a key-role in bioconstruction inclusion processes and raise questions on effective role of sabellariid bioconstructions as a trap for this pollutant in the littoral environment.


Assuntos
Poliquetos , Poluentes Químicos da Água , Animais , Microplásticos/análise , Plásticos , Monitoramento Ambiental , Mar Mediterrâneo , Poluentes Químicos da Água/análise
3.
Appl Radiat Isot ; 193: 110653, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36638625

RESUMO

Non-destructive characterisation of meteorites is here performed on a stony meteorite. The identification of the sample is performed by low-background γ-ray spectrometry in order to determine the presence of certain cosmogenic radionuclides, whereas a mineralogical phase quantitative analysis is carried out by Time-of-Flight Neutron Diffraction (ToF-ND) on the sample as-it-is. The protocol is then validated by applying micro-Raman Spectroscopy (µRS) and Energy Dispersive X-ray Spectroscopy (EDS). This paper is focused on γ-ray spectrometry, proving the meteoric origin of the sample, and it also presents some preliminary results of ToF-ND.

4.
Environ Monit Assess ; 184(7): 4461-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21830066

RESUMO

A new index named Air Quality Balance Index (AQBI), which is able to characterise the amount of pollution level in a selected area, is proposed. This index is a function of the ratios between pollutant concentration values and their standards; it aims at identifying all situations in which there is a possible environmental risk even when several pollutants are below their limit values but air quality is reduced. AQBI is evaluated by using a high-resolution three-dimensional dispersion model: the air concentration for each substance is computed starting from detailed emissions sources: point, line and area emissions hourly modulated. This model is driven with accurate meteorological data from ground stations and remote sensing systems providing vertical profiles of temperature and wind; these data are integrated with wind and temperature profiles at higher altitudes obtained by a Local Area Model. The outputs of the dispersion model are compared with pollutant concentrations provided by measuring stations, in order to recalibrate emission data. A three-dimensional high resolution grid of AQBI data is evaluated for an industrial area close to Alessandria (Northern Italy), assessing air quality and environmental conditions. Performance of AQBI is compared with the Air Quality Index (AQI) developed by the U.S. Environmental Protection Agency. AQBI, computed taking into account all pollutants, is able to point out situations not evidenced by AQI, based on a preset limited number of substances; therefore, AQBI is a good tool for evaluating the air quality either in urban and in industrial areas. The AQBI values at ground level, in selected points, are in agreement with in situ observations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Poluentes Atmosféricos/normas , Automóveis/estatística & dados numéricos , Humanos , Indústrias/estatística & dados numéricos , Itália , Modelos Químicos , Emissões de Veículos/análise
5.
Appl Spectrosc ; 75(7): 839-845, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33393352

RESUMO

Attenuated Total Reflection (ATR) spectroscopy coupled with a microscope allows for the analysis of specimens without any preparation, spatially correlated with the morphology of the specimen. These characteristics make micro-ATR systems very useful for studying gemstones and in particular amber samples. Indeed, in this report, the micro-ATR technique was used to characterize three Burmite samples, as case studies. Particularly, focusing the ATR crystal spot on the amber surface where a difference in the Ultraviolet (UV) reaction was previously detected, thereby relative differences in the IR spectrum could be analyzed. Here we present a methodology combining the UV imaging technique with the micro-Attenuated total reflection Fourier transform infrared spectroscopy (micro-ATR/FT-IR) analyses, in order to correlate the fluorescence information with the molecular vibrational modes of amber and their relative spatial distribution. Finally, this work is intended as an initial methodology study and part of the amber characterization project, focused on characterizing the Burmese amber collection of the Peretti Museum Foundation from several disciplines (i.e., palaeoentomology, vibrational spectroscopy, neutron tomography, etc.).


Assuntos
Âmbar , Microscopia , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Materials (Basel) ; 14(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34947185

RESUMO

Meteorite characterisation represents a privileged and unique opportunity to increase our knowledge about the materials composing the Universe and, particularly, the Proto Solar System. Moreover, meteorites studies evolve contextually with the development of analytical technologies. In the present paper, the results from an unclassified stony meteorite (chondrite) characterisation have been reported on the basis of the innovative analytical protocol presented here. Advanced Mapping by micro-Raman Spectroscopy and Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy have been combined to disclose molecular and elemental features on the same regions sample at a micrometric resolution. Thanks to their non-destructive properties, the mapping tools of both instruments have been applied to single chondrules analysis and the best match between the mineralogical information and the chemical composition has been obtained. This combined approach proved to be highly suitable in disclosing the crystallinity features of the phases, with in-depth spatial and morphological details too.

7.
Appl Spectrosc ; 64(6): 571-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20537223

RESUMO

In a previous work it has been demonstrated that micro-Raman spectroscopy is a technique able to recognize crystalline phases on untreated samples. In that case, inorganic particles and uncoated fibers from bronchoalveolar lavage (BAL) of a patient affected by pneumoconiosis were identified and characterized. In this work the technique is applied to asbestos bodies, that is, to coated fibers, and on crystallizations and fibrous phases observed in the plural plaque from patients affected by mesothelioma. From the Raman analysis the abundant fibrous material observed in the pleural area is talc, whereas rounded grains in the pleural tissue show the Raman spectrum of apatite, a calcium phosphate mineral particular to bones. In the pulmonary tissue many asbestos bodies, consisting of the incorporated fibers coated by iron-rich proteins, were observed. Under the 632.8 nm laser beam of the spectrometer, photo-crystallization of hematite in the iron-rich material forming the asbestos bodies can be proposed by the changes in the Raman spectra acquired during subsequent acquisitions. Nevertheless, the identification of the mineral phase constituting the incorporated fiber was possible by analyzing the Raman spectra; the results were confirmed by variable pressure scanning electron microscopy with annexed energy dispersive spectroscopy (VP-SEM-EDS) analyses.


Assuntos
Amianto/análise , Neoplasias Pulmonares/patologia , Pulmão/patologia , Mesotelioma/patologia , Microscopia Eletrônica de Varredura/métodos , Análise Espectral Raman/métodos , Humanos , Doenças Pleurais/patologia
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