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Your search keyword '"Valentini, S."' showing total 14 results
Start Over Author "Valentini, S." Publisher elsevier ltd
14 results on '"Valentini, S."'

6. Classifying aerosol particles through the combination of optical and physical-chemical properties: Results from a wintertime campaign in Rome (Italy)

Author

Valentini, S, Barnaba, F, Bernardoni, V, Calzolai, G, Costabile, F, Di Liberto, L, Forello, A, Gobbi, G, Gualtieri, M, Lucarelli, F, Nava, S, Petralia, E, Valli, G, Wiedensohler, A, Vecchi, R, Valentini S., Barnaba F., Bernardoni V., Calzolai G., Costabile F., Di Liberto L., Forello A. C., Gobbi G. P., Gualtieri M., Lucarelli F., Nava S., Petralia E., Valli G., Wiedensohler A., Vecchi R., Valentini, S, Barnaba, F, Bernardoni, V, Calzolai, G, Costabile, F, Di Liberto, L, Forello, A, Gobbi, G, Gualtieri, M, Lucarelli, F, Nava, S, Petralia, E, Valli, G, Wiedensohler, A, Vecchi, R, Valentini S., Barnaba F., Bernardoni V., Calzolai G., Costabile F., Di Liberto L., Forello A. C., Gobbi G. P., Gualtieri M., Lucarelli F., Nava S., Petralia E., Valli G., Wiedensohler A., and Vecchi R.

Abstract

The “Carbonaceous Aerosol in Rome and Environs” (CARE) experiment took place at a Mediterranean urban background site in Rome (Italy) deploying a variety of instrumentation to assess aerosol physical-chemical and optical properties with high-time resolution (from 1 min to 2 h). In this study, aerosol optical properties, chemical composition, and size distribution data were examined with a focus on the analysis of several intensive optical properties obtained from multi-wavelength measurements of aerosol scattering and absorption coefficients. The spectral behaviour of several quantities related to both aerosol composition and size was explored, analysing their high-time resolved temporal patterns and combining them in order to extract the maximum information from all the available data. A methodology to separate aerosol types using optical data only is here proposed and applied to an urban area characterised by a complex mixture of particles. A key is given to correctly disentangle cases that could not be distinguished observing only one or few parameters, but that can be clearly separated using a suitable ensemble of optical properties. The SSCAAE, i.e. the wavelength dependence of the Single Scattering co-albedo 1-SSA (where SSA is the Single Scattering Albedo) - that efficiently responds to both aerosol size and chemical composition – resulted to be the best optical intensive parameter to look at for the discrimination between episodes characterised by specific aerosol types (e.g. sea salt, Saharan dust) and more mixed conditions dominated by local emissions. However, this study also highlighted that it is necessary to combine temporal patterns of different optical parameters to robustly associate SSCAAE features to specific aerosol types. In addition, the complete chemical speciation and the high-time resolved size distribution were used to confirm the aerosol types identified via a combination of aerosol optical properties. Look-up tables with most suitable ran

Published
2020

13. Classifying aerosol particles through the combination of optical and physical-chemical properties: Results from a wintertime campaign in Rome (Italy)

Author

A.C. Forello, S. Valentini, Giulia Calzolai, G. Valli, Gian Paolo Gobbi, Maurizio Gualtieri, Silvia Nava, Roberta Vecchi, L. Di Liberto, A. Wiedensohler, V. Bernardoni, Francesca Barnaba, Franco Lucarelli, Ettore Petralia, Francesca Costabile, Valentini, S, Barnaba, F, Bernardoni, V, Calzolai, G, Costabile, F, Di Liberto, L, Forello, A, Gobbi, G, Gualtieri, M, Lucarelli, F, Nava, S, Petralia, E, Valli, G, Wiedensohler, A, Vecchi, R, Valentini, S., Barnaba, F., Bernardoni, V., Calzolai, G., Costabile, F., Di Liberto, L., Forello, A. C., Gobbi, G. P., Gualtieri, M., Lucarelli, F., Nava, S., Petralia, E., Valli, G., Wiedensohler, A., and Vecchi, R.

Subjects
Atmospheric Science, 3D optical data storage, Aerosol classification schemes, High time resolution, Intensive optical properties, food.ingredient, 010504 meteorology & atmospheric sciences, Single-scattering albedo, Scattering, Sea salt, 010501 environmental sciences, Mineral dust, 01 natural sciences, Aerosol, Intensive optical propertie, Wavelength, food, Environmental science, Absorption (electromagnetic radiation), 0105 earth and related environmental sciences, Remote sensing, Aerosol classification scheme
Abstract

The “Carbonaceous Aerosol in Rome and Environs” (CARE) experiment took place at a Mediterranean urban background site in Rome (Italy) deploying a variety of instrumentation to assess aerosol physical-chemical and optical properties with high-time resolution (from 1 min to 2 h). In this study, aerosol optical properties, chemical composition, and size distribution data were examined with a focus on the analysis of several intensive optical properties obtained from multi-wavelength measurements of aerosol scattering and absorption coefficients. The spectral behaviour of several quantities related to both aerosol composition and size was explored, analysing their high-time resolved temporal patterns and combining them in order to extract the maximum information from all the available data. A methodology to separate aerosol types using optical data only is here proposed and applied to an urban area characterised by a complex mixture of particles. A key is given to correctly disentangle cases that could not be distinguished observing only one or few parameters, but that can be clearly separated using a suitable ensemble of optical properties. The SSCAAE, i.e. the wavelength dependence of the Single Scattering co-albedo 1-SSA (where SSA is the Single Scattering Albedo) - that efficiently responds to both aerosol size and chemical composition – resulted to be the best optical intensive parameter to look at for the discrimination between episodes characterised by specific aerosol types (e.g. sea salt, Saharan dust) and more mixed conditions dominated by local emissions. However, this study also highlighted that it is necessary to combine temporal patterns of different optical parameters to robustly associate SSCAAE features to specific aerosol types. In addition, the complete chemical speciation and the high-time resolved size distribution were used to confirm the aerosol types identified via a combination of aerosol optical properties. Look-up tables with most suitable ranges of values for optical variables were produced; therefore, these pieces of information can be used at the same site or at locations with similar features to quickly identify the occurrence of aerosol episodes. Graphical frameworks (both from the literature and newly designed) are also proposed; for each scheme features, advantages, and limitations are discussed.

Published
2020
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14. Pre- and post-surgical evaluation of plasma lactate concentration in 45 dogs with gastric dilatation-volvulus: A preliminary study.

Author

Grassato L, Spinella G, Musella V, Giunti M, Vilar JM, and Valentini S

Abstract

This preliminary study was designed to contribute to the evaluation of reliability of plasma lactate concentration (PLC) and its clearance as predictive and prognostic factors of gastric necrosis and clinical outcome of dogs affected by gastric dilatation-volvulus (GDV). Main aims of the study were: 1) to evaluate the prognostic reliability of PLC at presentation (T0) in dogs with GDV, 2) to compare the obtained data and considerations with the veterinary literature, and 3) to introduce the possible validity of PLC values at 24 (T24) and 48 (T48) hours after surgery as a predictive factor. Dogs with GDV were retrospectively evaluated. PLC at T0, T24 and T48 were recorded and correlated to the presence or absence of macroscopic necrosis of the stomach and to outcome. Forty-five dogs met the inclusion criteria. Significant differences were not detected in the mean values between the initial PLC in dogs with and without necrosis of the gastric wall, as well as between surviving and non-surviving dogs; these values were not associated with higher risk of gastric necrosis or death. At T24 and T48 no significant differences were recorded between necrosis and non-necrosis, and surviving and non-surviving categories. A median plasma lactate concentration clearance from arrival to T24 ≥ 50% was identified in both groups (with and without necrosis), and this parameter failed in identifying dogs that survived to discharge. In conclusion, the results presented here failed to detect PLC at T0 and its clearance at T24 as prognostic factors in this population of dogs with GDV., (© 2020 Published by Elsevier Ltd.)

Published
2020
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